50 - PR-LSAMP · Amelia Babilonia, Chemistry Department José Terrón, Scientific Illustrator Nivea Santiago, Acting Director, CITEC Edwin Viera, CITEC Samuel Suleiman,CITEC Néstor

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50th ACS Junior Technical Meeting 35th Puerto Rico Interdisciplinary Scientific Meeting (PRISM)

University of Puerto Rico, Rio Piedras March 14, 2015

SPONSORED BY American Chemical Society – Puerto Rico Section Puerto Rico Louis Stokes Alliance for Minority Participation University of Puerto Rico, Río Piedras Campus

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50th ACS Junior Technical Meeting

35th Puerto Rico Interdisciplinary Scientific Meeting (PRISM) University of Puerto Rico, Río Piedras

March 14, 2015

TABLE OF CONTENTS

Map of the University of Puerto Rico, Rio Piedras Campus ........................................... 3 Organizing And Scientific Committees ............................................................................ 4 Invited Speaker ............................................................................................................... 5 Program Agenda ............................................................................................................. 7 Oral Sessions .................................................................................................................. 8

Agricultural Sciences ............................................................................................ 9 Computer Science .............................................................................................. 84 Education ........................................................................................................... 96

Electronics ........................................................................................................ 100

Engineering ...................................................................................................... 104 Environmental Sciences ................................................................................... 134 Geosciences ..................................................................................................... 188

Life Sciences .................................................................................................... 193 Mathematics ..................................................................................................... 300

Physics ............................................................................................................. 304 Poster Session ............................................................................................................ 317

Chemistry ......................................................................................................... 318

Education ......................................................................................................... 334 Electronics ........................................................................................................ 337 Engineering ...................................................................................................... 339

Environmental Sciences ................................................................................... 342 Geosciences ..................................................................................................... 355 Life Sciences .................................................................................................... 357 Mathematics ..................................................................................................... 374

Physics ............................................................................................................. 380

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Map of the University of Puerto Rico, Rio Piedras Campus

2015 JTM/PRISM at Natural Science Building

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University of Puerto Rico, Río Piedras March 14, 2015

Organizing and Scientific Committees

RCSE Frederick A. Just-Agosto, Acting Director María Vargas-Capriles, Associate Director José A. Muñoz-Álvarez, Special Assistant Héctor R. Méndez-Rubio, Admin. Assistant Antonio Martínez-Collazo, PR-LSAMP Co-PI Javier Figueroa-Santiago, Academic Coordinator Zulma I. Crespo-Figueroa, Management Coordinator Yalinet Acevedo-Torres, Admin. Assistant ACS-Puerto Rico Edmy Ferrer, Chair Carlos Olivo, Past Chair Brenda Ramos, Chair Elect Viviana León, Secretary Jorge Colón, Treasurer Sara M. Delgado, Northeastern Representative José I. Ramírez, Southeastern Representative Nestor Carballeira, Councilor Angela González, Councilor Agnes Dubey, Councilor Myrna Otaño, Alternate Councilor Jorge Colón, Alternate Councilor Carlos Ruíz, Alternate Councilor Ingrid Montes, ACS Director at Large

University of Puerto Rico, Río Piedras Carlos I. González, Dean College of Natural Sciences Noel Motta, Associate Dean, Academic Affairs Ingrid Montes, Assistant Dean, Grad. Studies and Research Carlos Pereira, Assistant Dean, Administration Agnes Vázquez, Assistant Dean, Student Affairs Tugrul Giray, Director of Biology Department Juan C. Ramírez Lugo, Biology Department Néstor Carballeira, Director of Chemistry Department Francisco Echegaray, Chemistry Department Eduardo Nicolau, Chemistry Department Rafael Arce, Director of Computer Science Department Ivelisse Rubio, Computer Science Department José F. Nieves, Director of Physics Department Peter Feng, Physics Department Antonio Martínez, Physics Department Iván Cardona, Director of Mathematics Department Luis Medina, Mathematics Department Elvia Meléndez, Environmental Sciences Gary Gervals, Environmental Sciences Yamir Torres, Special Assistant Amelia Babilonia, Chemistry Department José Terrón, Scientific Illustrator Nivea Santiago, Acting Director, CITEC Edwin Viera, CITEC Samuel Suleiman,CITEC Néstor Pacheco, Administrative Asistant UPR, Central Administration Uroyoán Walker-Ramos, UPR Preisdent, PR-LSAMP PI José A. Lasalde-Dominicci, Vice President for Research and Technology Gladys Escalona de Motta, Associate Vice President for Research and Technology

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University of Puerto Rico, Río Piedras March 14, 2015

INVITED SPEAKER

Dr. Angel A. Martí

Department of Chemistry Rice University Houston, Texas

Changing the Paradigm for the Detection of Biomolecules: A Story of Metals, Light, and Time

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SHORT BIO

Angel A. Martí is currently an Assistant Professor of Chemistry, and Assistant Professor of Bioengineering at Rice University in Houston. While an undergraduate student at the University of Puerto Rico, Río Piedras, from 1996 to 1999 he was awarded the Alliance for Minority Participation Excellence award and NIH/SUBE research fellowship. He obtained his BS degree in Chemistry in 1999. In 2004 he obtained his PhD degree from the same university under the supervision of Dr. Jorge Colón, where he held the NSF Graduate Teaching Fellowship in K-12 Education and NIH-RISE fellowship. During his Ph.D. Dr. Angel Martí studied the photophysical properties of metal complexes immobilized in layered zirconium phosphate materials. In 2004 he joined Prof. Nicholas Turro’s (at the time considered by many the world’s most renowned photochemist) Research Group at Columbia University as a Postdoctoral Research Scientist, where he worked in the development of fluorescent probes for the detection of trace amounts of DNA and mRNA in vivo and in vitro, ortho-para hydrogen conversion, singlet oxygen deactivation and in supramolecular and nanoscale systems. In July 2008, Dr. Angel Martí joined the Department of Chemistry at Rice University in Houston, with secondary appointments in the Department of Bioengineering and Materials Science and Nano Engineering. Currently he has published over 50 manuscripts, some of the most recent on sensing biomolecules in complex environments, supramolecular photochemistry and carbon nanotechnology. He was also conferred the 2013 Inter-American Photochemical Society Young Investigator Award and the 2014 American Society for Photobiology New Investigator Award.

ABSTRACT

Certain metal complexes have unusual properties such as red photoluminescence, large Stokes shifts, and long lifetimes. These features have a wide demand in the design and synthesis of molecular sensors with different applications. In this presentation, time resolved spectroscopy in combination with photoluminescent metal complexes will be used to solve problems commonly encountered when using conventional sensors and fluorophores. First, it will be demonstrated how using time windows is an effective method to improve the performance of photoluminescent sensors to detect specific DNA sequences. Similarly, time-resolved spectroscopy will be used in combination with sensors with long lifetimes, to illustrate how the amino acids cysteine and histidine can be detected even on media with high autofluorescence. Similar principles will be used to detect beta amyloid peptide aggregation ("β-amyloid" which has been linked to Alzheimer's disease) and alpha synuclein protein ("α-synuclein" associated with Parkinson's disease) by ruthenium complexes. We will also present how zeolitic materials containing rhenium complexes can be used in combination with steady state and time-resolved fluorescence spectroscopy to detect vapors of different solvents.

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University of Puerto Rico, Río Piedras

March 14, 2015

PROGRAM AGENDA

07:30 a.m. – 10:00 a.m. Registration Lobby Amphitheatre 1 College of General Studies

07:30 a.m. – 10:00 a.m. Breakfast Lobby Amphitheatre 1 College of General Studies

09:00 a.m. – 09:30 a.m. Welcoming Remarks Amphitheatre 1 Uroyoán Walker, Ph.D., President University of Puerto Rico

José A. Lasalde-Dominicci, Ph.D.

Vice President for Research University of Puerto Rico

Carlos Severino, Ph.D., Chancellor University of Puerto Rico at Río Piedras

Mary Kirchhoff, Ph.D. Director of ACS Education Division

Carlos González, Ph.D., Dean College of Natural Sciences, University of

Puerto Rico at Río Piedras María Vargas, Associate Director Resource Center for Science & Engineering

Antonio Martínez-Collazo, Ph.D. Co-PI PR-LSAMP

Edmy Ferrer, Ph.D., Chair American Chemical Society – Puerto Rico

Section

09:30 a.m. – 09:45 a.m. Presentation of Plenary Speaker Amphitheatre 1, College of General Studies

Jorge Colón, Ph.D., Professor Department of Chemistry University of Puerto Rico at Río Piedras

09:45 a.m. – 10:45 a.m. Plenary Conference Amphitheatre 1, College of General Studies

Angel Martí, Ph.D., Assistant Professor Rice University

University of Puerto Rico at Río Piedras

11:00 a.m. – 12:00 p.m. Concurrent Scientific Sessions Natural Sciences Building 11:30 a.m. – 01:30 p.m. Lunch Lobby Amphitheatre 132,

College of Natural Sciences

08:00 a.m. – 03:00 p.m. Poster Set Up Lobby Natural Sciences Building 01:45 p.m. – 03:40 p.m. Concurrent Scientific Sessions Natural Sciences Building 03:00 p.m. – 05:00 p.m. Poster Session Lobby Natural Sciences Building 5:00 p.m. A Tribute to Dr. Waldemar Adam

and Past ACS-PR Presidents CN-142

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Oral Sessions

Titles for Oral Sessions (Arranged in Alphabetical order

by field and presenter´s last name)

● Agricultural Sciences

● Chemistry

● Computer Sciences

● Education

● Electronics

● Engineering

● Environmental Sciences

● Geosciences

● Life Sciences

● Mathematics

● Physics

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Agricultural Sciences

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Alvarez-Torres, Beverly

Alvarez Torres, Beverly - Biología, UIA-San Germán


Effect of soil pH changes in nitrogen-fixing bacteria present in crops of Musa cavendishii (banana) and Musa paradisiaca (plantain)

In this research, we demonstrated that changes in pH may affect microbial population and land and plant productivity. We used Musa cavendishii (banana) and Musa paradisiaca (plantain) as part of this study. These crops are very important for the economy of towns in Puerto Rico, such as Yauco, Guayanilla, Mayagüez, and Añasco, providing a lot of employments, monetary profits, and hogging large quantities of agricultural land. Currently, conventional crop growing methods are used in this towns, including irrigation, fertilization, plowing the land, and gathering. However, studies show that the use of certain techniques, like the use of organic fertilizers or pesticides, crop rotation, weather events, and certain forms of irrigation, can affect the soil pH compromising the land quality and the development of the plant. The importance of the pH to ecological level is that it has the ability to provide specific characteristics to soils, whether physical, chemical, biochemical, and/or microbiological, which may be affected by changes caused by nature or man. Some of the negative effects that this could cause is nitrogen deficiency diseases in the plants. This problem may be caused by a decrease in nitrogen-fixing microorganisms, the availability to retain nutrients and water, temperature, and photosynthesis. We evaluated the presence, survival or absence of nitrogen fixing bacteria in soils from those crops changing the nitrate agar pH to acidic pH 3 and basic pH 12. When we changed the pH, the bacterial population was largely affected, proving the importance of monitoring the pH for optimum crop production.

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Morales-Feliciano, Abisrael

Perez Jimenez Jose


Fungi belowground in agricultural settings

Molds and yeasts are microorganisms essential for natural processes in soils.These organisms are heterotrophic and their main source of nutrient is dead organic matter. Plants are associated with fungi that help to fight harmful bacteria and develop faster. The objective of this research is to isolate and identify the molds and yeasts belowground in agricultural soil.Soil samples were collectedseven sites in an agricultural site (Gurabo, Puerto Rico), diluted in salinesolution (up to 10-7) and cultivated in DichloranRoseBengalChloramphenicol Agar for one week. Different colonies were isolated into Potato Dextrose Agar and a sterile coverslip was superposedto each isolate.For identification of pure cultures, sandwich wet mounts were prepared with coverslips removed from plates and lactophenol-cotton blue. Fungal isolates were identified by microscopic examination using taxonomical references. Fungal diversity included eight genera at least, including Aspergillus sp., Humicola sp., Penicilium sp., Fusarium sp., Cladosporium sp., Scopulariopsis sp., Curvularia sp., and Thricoderma sp. Greater diversity was found at lower dilutions. Understanding the microbial life of these soils allow us to find fungi with antimicrobial and bioremediation capabilities. This knowledge would help improve the quality and productivity of agricultural processes.

Ramos-Camacho, Elisa

Medina-Laabes, Diana - Biology Department, University of Puerto Rico at Humacao; Rodriguez-Velez, Ileana I. - Chemistry Department, University of Puerto Rico at Humacao


Essential oils exhibited insecticide activity against the coffee berry borer Hypothenemus hampei (Curculionidae)

The coffee berry borer, Hypothenemus hampei is the main pest affecting coffee crops at a worldwide level. This beetle infects 12 commercial species belonging to

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the genus Coffea. Currently, the insecticides mainly used for the control of this pest are highly toxic to human health and the environment due to their slow degradation in soil. Our main objective in this project is to develop safer strategies (natural insecticides, deterrents and attractants) to combat this pest. Previous research has shown the insecticidal activity of essential oil extracted from Ylang-ylang leaves (Cananga odorata) against the maize weevil Sitophilus zeamais. As S. zeamais and H. hampei belong to the family Curculionidae, we tested the potential insecticide activity of C. ododata essential oils extracted from its flowers. In a preliminary assay using 100% of this oil against the borer, we observed 100% lethality. In consequence, we tested a series of essential oil solutions (C. odorata, Syzygium aromaticum, Cinnamomun zeylanicum, Callistemon citrinus and Illisium verum) with an oil concentration of 5% and 2.5% (v/v). In order to perform this task, we first obtained the essential oils from flowers, seeds or leaves of the plants mentioned above by hydrodistillation. This assay was performed under two experimental conditions: (1) in absence of a coffee bean and (2) in presence of a coffee bean. To this point, our results have given indications that the essential oil of C. odorata flowers could be considered a promising organic insecticide against H. hampei.

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Rivera-Ocasio, Zoelie

Rivera Ocasio, Zoelie - Center for Excellence in Quarantine and Invasive Species, UPR, 1193 Calle Guayacan, San Juan 00926 PR.; Verle Rodrigues, Jose Carlos - Center for Excellence in Quarantine and Invasive Species, UPR, 1193 Calle Guayacan, San Juan 00926 PR.


Feeding behavior of Diomus flavifrons (Coleoptera:Coccinellidae), a predator of Hypogeococcus pungens (Hemiptera:Pseudococcidae).

The natural cacti communities in Puerto Rico have experienced significant challenges with Harrisia cactus mealybug (HCM) infestation. The study on natural enemies of this invasive mealybug, Hypogeococcus pungens (Hemiptera:Pseudococcidae), has become an important topic recently. Galls of a columnar cactus, Pilosocereus royenii, resulting from the infestation of HCM were inspected for the occurrence of natural enemies. Three predator species of lady beetle (Coleoptera:Coccinellidae), Cryptolaemus montrouzieri, Scymnobius flavifrons, and Decadiomus austrinus, were collected and identified. Lady beetle are among the best-known beneficial predatory insects because their high performance. Predatory behavior of Scymnobius flavifrons adults on HCM was studied. The predator-prey interaction was observed among adults of the predator and different instars of HCM: crawlers, adults and endoparasitic adults (“mummies”). The predator was observed walking around the prey, cleaning the wax surface that protect adults of HCM, touching and feeding on all prey stages, cleaning them, resting between feeding events, vibrating wings, and excreting. The initial time to the predator to attack the prey was not distinctive for the different instars of HCM. However, the ladybeetle predator showed a decreasing feeding preference over crawlers, adults, and mummies.

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Adorno-Rivera, Cindy

Carballeira, Nestor - Chemistry, UPR-Río Piedras; Montano, Nashbly - Chemistry, UPR- Río Piedras; William Marrero - Chemistry, UPR-Río Piedras

Chemistry

First Total Synthesis of 5Z,9Z,13Z-2R-methoxyoctadecatrienoic acid Isolated from the Caribbean Sponge Asteropus niger.

Natural products have been the source of new structural entities having potential pharmacological activity. In addition, they are a motivation to develop new synthetic strategies for their construction. The 2-methoxylated fatty acids are rare in nature and have principally been identified in the phospholipids of sponges. Our group recently identified, in the Caribbean sponge Asteropus niger, the 5Z,9Z,13Z-2R-methoxyoctadecatrienoic acid with a relative abundance of less than 1%. This acid is new in nature and could display interesting biological activities for its polyunsaturation pattern. Our approach in this work is to synthesize the 5Z,9Z,13Z-2R-methoxyoctadecatrienoic acid in order to examine its biomedical properties. Our progress towards the first total synthesis of this acid from 1, 5-hexadiyne will be presented.

Adorno-Rivera, Linet

Andrea RuIz Mojica - Interdisciplinary Program ; María del Mar Cordero Landrón - Interdisciplinary Program ; Enrique Fraile - Department of Chemistry; Mariela Fuentes Caraballo - Department of Chemistry; Loretta Roberson - Department of Environmental Science; Liz Díaz Vázquez - Department of Chemistry

Chemistry

Caribbean macro-alga Osmundaria obtusiloba as potential reducer for gold nanoparticles biosynthesis

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Chemical components found in marine algae can be use in different aspects of bio-energy, nutrient formation and bio-medics. Recent studies show that fungi extract, aquatic and terrestrial plants serve as an efficient metal nanoparticles (NPs) synthesizer. In this study, the main objective is to biosynthesize gold nanoparticles (Au NPs) with Osmundaria obtusiloba extract. The algae extract contains reducing compounds that when subjected to 1mM of gold solution, Au NPs are formed. UV-Visible spectroscopy was used to monitor the formation of metal NPs by analyzing the absorbance of the metallic solutions. Formation of Au NPs was evidenced by absorbance in the predicted wavelength region at a range of 540nm and expected color changes from yellow to violet in solution. The metallic nanoparticles were characterized using Scanning Electron Microscopy (SEM) and Fourier Transform Infrared Spectroscopy (FTIR). These analyses are used to determine particle size, morphology of nanoparticles and the identification of biomolecules for capping and efficient stabilization of metal nanoparticles, respectively. This procedure has developed an eco-friendly and cost-effective method in which biosynthesize gold NPs have formed and continuous to optimize the morphology of the NPs to develop unique properties.

Bas-Concepcion, Jesbaniris

Arnulfo Rojas - University of Puerto Rico, Río Piedras Campus; Irma López - Puerto Rico Aqueduct Sewer Authority; Dra. Liz M. Díaz Vázquez - University of Puerto Rico, Río Piedras Campus

Chemistry

Bio-oil production from Wastewater Sludge by Direct Hydrothermal Liquefaction Technology

Sludge of municipal wastewater treatment facilities is an unavoidable secondary pollution generated in the process of sewage treatment. Currently, traditional methods of treating sludge (e.g. incineration, landfill or land application) have some drawbacks and shortages. Direct hydrothermal liquefaction (HTL) of sludge is a novel treatment method with the added benefit of energy recovery. In the presented study, the viability of uses the Puerto Rico Aqueduct Sewer Authority’s (PRASA) plant facilities sewage for the production of bio-oil was investigated. Sludge form different wastewater treatment facilities and at different stages of the treatment (raw, primary and secondary sludge) were chemically characterized and liquefied at a temperature of 3000C, at a pressure of 12MPa, with and without catalyst. Loading of 20 wt% of sludge/water were added to a batch type reactor. For most of sewage

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sludge, oil production proceeded satisfactory. The generated biooils were characterized with GCMS, FTIR and CHONS analysis. Energy balance, bio-oil yield and composition of the HTL process for the different sludge will be discussed. Keywords: Sludge, biooil, energy recovery hydrothermal liquefaction

Benitez-de la Vega, Marimar

Molina, Anna M. - Chemistry, UPR-Rio Piedras; Griebenow, Kai - Chemistry, UPR-Rio Piedras

Chemistry

Development of an amygdalin delivery system for cancer treatment

Cancer, a malignant growth resulting from the division of abnormal cells, is the second leading cause of death in the U.S. This heterogeneous group of diseases has been studied for the last decades but the effectiveness of current treatments is often limited due to their toxicity to healthy tissue or low tumor specificity. Therefore, development of efficient cancer tumor-targeted and less toxic to normal cells therapies is a top priority in biomedical research. In our research, we proposed to design a nanoparticle (NP) drug delivery system that enables administration of amygdalin, a natural cyanide-containing substance for cancer treatment, in an aqueous phase medium to significantly improve its potential clinical applications. Our working hypothesis was to synthesize and select the optimum characteristics of a poly-(lactic-co-glycolic acid) (PLGA) NP based amygdalin delivery system that exploits the differences of the tumor microenvironment and selectively accumulates in the cancer tissue, enters the malignant cells and is released. We prepared the amygdalin-PLGA NPs using the double-emulsion-solvent evaporation method. The system was physically characterized using Scanning Electron Microscopy and Dynamic Light Scattering in terms of morphology and size, respectively. The NPs size obtained (269 nm) was appropriate for accumulation and retention in cancer tissue. Moreover, we sought to verify the cytotoxicity of the system in HeLa cells by performing cell viability assays. We observed a dose-dependent cytotoxicity. Finally, future work includes the optimization of the system’s physiochemical characteristics to improve drug encapsulation efficiency and determine the cell death mechanism by conducting a cell free caspase-3 and 9 assays.

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Caban-Badillo, Jeanna

De Jesus Echevarria, Maritza* - Chemistry, University of Puerto Rico-Mayaguez Campus

Chemistry

AROMA CONSTITUENTS in SPONDIAS CYTHEREA by HS/SPME and GC/MS

The Spondias cytherea and/or Spondias dulcis fruit is a not well known fruit for almost the entire world, except from certain parts of south Asia and some tropical and subtropical areas. The aroma compounds of the pulp fruits of Spondias cytherea were analyzed by HS/SPME and GC/MS with and without water from Añasco, Rincón and Isabela municipalities of Puerto Rico at room temperature. A total of 105 compounds were found and 63 were identified. As main compounds, alpha-pinene, butanoic acid ethyl ester, (E)-2-hexenal and acetic acid ethyl ester are among the three municipalities. The characteristic aroma impressions of the pulp can be correlated to identify minor alcohols and esters, and monoterpenes.

Caldero-Rodríguez, Naishka Enid

Ingrid Montes González, Ph. D

Chemistry

Synthesis and characterization of Ferrocenyl Oximes

Ferrocene is known to exhibit a wide range of biological activity. Many ferrocenyl compounds display interesting cytotoxic, antitumor, antimalarial, anti-fungal and DNA cleaving activities. Obtained from the Claisen-Schmidt reaction of acetylferrocene or ferrocenecarboxaldehyde with substituted benzaldehydes or acetophenones, ferrocenyl chalcones have been paid much consideration for their synthetic versatility. Chalcones could be transformed into oxime derivatives. Like oximes, ferrocene-based ligands have been employed in various fields, such as

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semiconductors, biosensors, asymmetric catalysis, and nonlinear optics. Likewise, oximes have other applications, such as antibacterial and anti-inflammatory applications. Our hypothesis is that oximes derivatives from ferrocenyl chalcones will exhibit an enriched antibacterial activity. This research is focused in the synthesis of ferrocenyl chalcones with different substituents, -Cl, -OMe, and their spectral and electrochemical characterization. These ferrocenyl chalcones were synthetized by a solvent-free approach and presented moderate to good yields. Also, it is of interest the collaborative-based biological testing for S. saprophyticus, B. cereus, S. aureus, K. pneumoniae, E. coli, and P. aeruginosa bacterias. These three specific aims will be elaborated.

Cantres-Rosario, Yadira

Diaz, Tanya L. - UPR Rio Piedras; Rivera, Jose M. - Chemistry Department, UPR Rio Piedras

Chemistry

Evaluation of the Immunomodulatory Activity Supramolecular Assemblies of 8-Aryl-2’-deoxyguanosine Derivatives

Toll-like receptors (TLRs) are type 1 intermembrane proteins that are present in certain cells of the Immune System. During their activation, these receptors play an important role in the signaling for the transcription and synthesis of cytokines responsible for immune responses against pathogens. To be activated, TLRs must recognize specific antigens or molecules generally associated with threats called pathogen associated patterns (PAMPs). TLR7, among several TLRs encountered in humans and other mammals, has been shown to recognize guanosine derivatives. Our group previously reported 8-aryl-2’-deoxyguanosine (8ArG) derivatives that have the capacity to self-assemble into stimuli responsive (e.g., temperature, pH) supramolecular-G-quadruplexes (SGQs), to further self-assemble into mesoglobular systems called supramolecular hacky sacks (SHS). Recent preliminary data show that SHS have the potential to activate an immune response associated to different cytokine profiles that could be related with TLR activity. Given the structural similarities shared by TLR7 and TLR8, and the affinity of TLR7 for guanosine derivatives, we hypothesized that the origin of the immunostimulatory activity relates to binding of TLR7 by 8ArGs. In order to test this hypothesis we performed commercially available TLR7 activation cell-based assays using a “HEK Blue” system. We will present the results of such assays and will compare the activity of the SHS with that of known TLR7 agonists like Imiquimod and Loxoribine.

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Capeles-Segarra, Ricardo

Rojas, Gabriel; Vega, Jorge E.; Román, Armando; Habiba, Khaled

Chemistry

Synthesis of Silver Nanoclovers and Nanocomposites using Cocoa Drink and Instantaneous Coffee as Reducing and Stabilizing Agents

Silver nanoclovers (Ag-NCV) and silver nanocomposites (Ag-NCP) were synthesized using the extract of cocoa drink and instantaneous coffee as a reducing and stabilizing agent with silver nitrate. To study their chemical and physical properties, we characterized Ag-NCV and Ag-NCP by UV-Vis spectroscopy, FTIR, X-ray diffraction, Raman spectroscopy and Scanning electron microscopy (SEM). The SEM images reveals that their average size is in the range of 30 – 100 nm. The antibacterial effect of silver nanoparticles produced in this study was studied against two fruits pathogenic bacteria Escherichia coli and Staphylococcus aureus. Moreover, we tested their applicability as fungicidal agents against fruit molds. Also the applicability of Ag-NCV in surface enhanced Raman spectroscopy (SERS) was evaluated in order to detect small concentration of bacterial cells. The Raman spectrum of small concentration of Staphylococcus aureus was detected with the aid of Ag-NCV. Thus, the synthesized silver nanoparticles may be good candidates in future for different applications such as in the fabrication of agricultural pesticides and detection of pathogens.

Carrasquillo-Pena, Keysha L.

Carrasquillo, Keysha L. - Biology, Universidad del Turabo

Chemistry

Locomotion and anxiety-related observations in zebrafish (Danio rerio) exposed to sublethal levels of Pb2+/Cu2+

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In this study, we utilize the Novel Tank Diving Test and the Light/Dark Choice Assay, to compare initial responses to unfamiliar environments as indicators of zebrafish anxiety/depression-like behavior after being exposed to sublethal levels of lead and copper ions. The Novel Tank Diving Test, used by Levin et al. (2007), is based on the tendency of zebrafish to remain in the side and bottom contact with solid boundaries in a novel tank/environment. Zebrafish are transported individually from their home tank to the treatment beaker containing 0.015 and 1.3 mg/L of lead or copper, respectively, and left there for one hour. Then, fish are transferred to the novel tank with careful handling to reduce net-stress. Recording starts and continues for a period of 5 min, tracking behavioral endpoints. Each zebrafish is given a subject number and the recorded video file name is changed accordingly, to correlate to that zebrafish number. The recorded videos are then analyzed. Two iPhone® Apps are used in the study as per Pittman & Ichikawa (2013); SwingReader Golf Lite™ (Company 11 Under, LLC) and Sports Motion Analyzer™ (The Sports Mechanic, LLC). Currently, these apps provide exceptional slow motion video capability and analysis tools to track movement. Both can be obtained for free or a low cost. Results will be presented during the conference.

Castro-Rosado, Waila

Chemistry

Development of biosensor using the surface of the electrode chemiclly modified for the detection of molecules with biological relevance.

In this presentation we will report results from our research project which aims to develop improved bio-sensors that can detect neutral molecules of biological relevance in the presence (and absence) of ionic interfering species. Previous research has shown that coating electroactive surfaces, such as platinum (Pt), with stable polymers could serve optimize the electrode selectivity. It has been demonstrated that the Nafion® polymer may be used. A primary objective of our research during this period has been the determination of the stability and the uniformity of Nafion® films created in our laboratory. In the experiments, we have used cyclic voltammetry (CV) as an electroanalytical technique for the characterization of Nafion®-modified bulk polycrystalline Pt working electrodes. Using this technique we have demonstrated the Nafion® coatings are stable and that these layers do increase the selectivity of the electrode towards a neutral electroactive target molecule (catechol) vis-à-vis an archetypal interfering electroactive anion (ferrocyanide). As a path forward, Platinum nanoparticles are

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currently being used as an electrocatalyst material, with the purpose of producing nanostructured electrode surfaces and to test the hypothesis that such nanostructured surfaces could be tailoring to produce more sensitive and more selective electrocatalytic surfaces.

Cintron-Cintron, Rodolfo

Roberson, Loretta - Department of Environmental Sciences, University of Puerto Rico, Rio Piedras; Diaz-Vazquez, Liz - Department of Chemistry, University of Puerto Rico, Rio Piedras

Chemistry

Isolation and Characterization of Polysaccharides from Different Macroalgae Species

The complex polysaccharides from brown, red and green macroalgae possess broad spectrum of therapeutic properties and industrial applications such as antioxidants supplements, their use for the fabrication of bioplastics and membranes for water purification. Hot water extracts (HWE) of three different species: Ulva lactuca, Glacilaria spp. and Osmundaria spp were studied for their polysaccharide content. Relatively high percent of polysaccharides were extracted (10 to 25%). Seasonal variation and environmental conditions impact on the polysaccharide content of the species were also studied alongside. Soluble polysaccharides (PS) were isolated separately from the samples of macroalgae, collected at different months from a single location for seasonal analysis and from different locations for the environmental conditions impact analysis. Yield (15 to 25%) and viscosity of HWE were higher during the active period of growth of algae. Infrarred spectroscopy (ATR/FTIR), Differential Scanning Calorimetry (DSC) and gas chromatography/mass spectrometry (GC/MS) analysis were performed to investigate the chemical composition and stability of the polysaccharide products (PP). It was found that sulfated polysaccharides were present in all the extracted products and thermal stability fluctuate between 200 to 310 oC. Due to their properties, the obtained polysaccharide mixtures can be considered, pure or modified, as a versatile biodegradable starting material for different applications, including tissue engineering, fabrication of bioplastics and membrane for water purification.

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Claudio-Tirado, Krystal L.

Olivo Vázquez, Alexander - Chemistry, University of Puerto Rico-Mayaguez Campus; De Jesús Echevarría, Maritza* - Chemistry, University of Puerto Rico-Mayaguez Campus

Chemistry

A SIMPLE METHOD FOR THE DETERMINATION OF ORGANIC COMPOUNDS IN SOIL SAMPLES USING HS/SPME AND GC/MS

One of the major fields in analytical chemistry is the development of faster and easier methodologies for characterization and quantification of trace compounds in complex matrices like soil. A simple and rapid solid-phase micro extraction procedure was developed using headspace solid-phase microextraction, HS/SPME and GC/MS for the determination of organic compounds in soil samples. Five commercially available SPME fibers were compared for efficiently determining and other SPME parameters were optimized. The soil was air dried and finally sieved. The PDMS-DVB pink fiber showed excellent extraction efficiency using 3-6g of soil, 2g of NaCl with 10-15ml of water. The validated method was used in soils from different municipalities of Puerto Rico. More than 73 compounds were found and 35 identified in the selected soils. Some of the compounds found in the different soils are toxic. Galaxolide a polycyclic organic synthetic musk that is used in some perfumes as a fragrance, that is detrimental for environmental life was found.

Collazo-Acevedo, Glorimaris

Torres Teissonniere, Carlos F. - Chemical Engineering, University of Puerto Rico-Mayaguez Campus; De Jesús Echevarría, Maritza* - Chemistry, University of Puerto Rico-Mayaguez Campus

Chemistry

Total Suspended Particulate (TSP) Index in the island of Puerto Rico

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The distribution of the total suspended particles, TSP/PM10 depends on the sources, meteorology conditions, or time of year, and samples locations. Particles are either emitted by fossil-fuel incomplete combustion, metallurgical process, natural events such as volcanoes and dust storms. The Mayagüez Station located in the Chemistry Department of the University of Puerto Rico are recording the TSP from 2004 to the present in order to generate a database to correlate any atmospheric activities, the Sahara Desert Storm, SDS and volcanic ash plume from the Soufriere located in the island of Montserrat in the Caribbean. The TSP value from Mayagüez Station was compared with the data from the different stations located around the island provided by the “Junta de Calidad Ambiental the Puerto Rico”, JCA during the wet season in 2014. The highest TSP value was reported during August month except from Mayagüez. The TSP value from Guayama, Guaynabo I, Guaynabo II, Ponce and Mayagüez stations do not exceded the Environmental Protection Agency, EPA arithmetic mean for TSP/PM10, no more than 50 µg/m3 and 150 µg/m3 during a 24 hour period.

Colon-Miranda, Jeidimar

Colón Miranda, Jeidimar - Chemistry, UPR Cayey; Ospina Millan, Claudia - Chemistry, UPR Cayey

Chemistry

Study of the Chemical Composition of Goetzea elegans

Goetzea elegans, is an endemic plant of Puerto Rico belonging to the Solenaceae family. This tropical plant was collected in San Juan, dried an extracted with a mixture of Hexane. The resulting crude extract was suspended in water and extracted with solvents of different polarities. The leaves crude extract of the plant was studied and the spectrum show the most predominant signals correspond to aliphatic protons, although there are minor resonances in the vynilic and allylic regions of the spectrum. Also, the leaves prepared in our laboratory were preliminary screened using the brine shrimp lethality test . However, the spectrum of the cortex of the plant show predominant signals corresponding to Aliphatic protons. The C13 spectrum show signals at aliphatic regions and minor resonance at vynilic and allylic regions. There are no literature reports of the chemical composition or biological activities of the Goetzea elegans species. As a future work we need to do an evaluation of cytotoxicity of the pure compounds against cancer cell lines and purification of the main compound of the hexane extract.

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Colón-Suarez, Ana C.

Rivera-Portalatín, Ph.D, Nilka M. - Department of Chemistry, University of Puerto Rico- Mayaguez

Chemistry

Bioactivity and Antioxidant Capacity of Cnidoscolus chayamansa Plant Stem Extracts

Cnidoscolus chayamansa (also known as Chaya) is a plant native to Central America which serves as an example of the various medicinal plants widely used in folkloric medicine. These plants usually have a wide variety of natural products that posses varying degrees of bioactivity. Previous research has demonstrated that extracts of the leaves of Cnidoscolus chayamansa posses bioactivity in the form of antioxidant properties and anticancer activity against the colon cancer cell line (HT-29). This investigation focuses on the plant’s stem. Extracts of the stem in hexane, dichloromethane and methanol are evaluated in order to determine their bioactivity and antioxidant capacity. The brine shrimp lethality assay is used to determine the bioactivity, which identifies a strong correlation to anticancer properties. In addition, antioxidant properties were determined by analysing the total phenolic content and using the di(phenyl)-(2,4,6-trinitrophenyl)iminoazanium (DPPH) assay. This investigation also focused on identifying the different types of compounds in each extract using qualitative properties. Future studies would center on further testing of the anticancer properties of the plant stem extracts on the colon cancer cell line (HT-29).

Cordero-Mercado, Salimar

Cruz, Raul - Chemical Engineering, UPRM; Lopez, Martha L. - Chemistry, UPRM

Chemistry

Effect of NaHS on the uptake of CeO2 Nanoparticles by Medicago sativa L. plants

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In recent years, nanoparticle development has grown exponentially and their use has attracted the attention of many scientific fields such as environmental chemistry. Nanoparticles might cause possible adverse effects on living organisms such as plants decreasing the nutrient uptake and growth development. The aim of this research is to study the effect of NaHS on Medicago sativa plants exposed to CeO2 nanoparticles. Four different concentrations: 100 ppm, 250 ppm, 500 ppm, and 750 ppm of CeO2 nanoparticles were mixed with soil. Plants were grown in these treatments and harvested after 38 days. Plants were separated in roots, stems, and leaves and saved for further experiments. Roots and stem length from all treatments was recorded. Results revealed that roots decreased in length when the concentration of nanoparticles increased in the soil. On the other hand, stems grew better in 250 ppm treatment with an average of 0.65 ± 0.10 cm. Chlorophyll content did not change significantly in all treatments, however, the highest value was obtained in leaves of plants exposed to 100 ppm of nanoparticles (31 ± 0.8). Catalase activity was higher (2.67 ± 0.08 ?molmin-1mg-1) in alfalfa plants grown in soil amended with 750 ppm of CeO2 nanoparticles. Ce concentration will be quantified by Inductively Coupled Plasma Spectroscopy (ICP/OES).

Correa-Lopez, Karina Michelle

Mahmoud Matar - Chemistry Department UPRH; Iris Flores - Chemistry Department UPRH; Lilliam Casillas - Biology Department UPRH; Ezio Fasoli - Chemistry Department UPRH

Chemistry

Characterization and purification of an halophilic esterase from the Cabo Rojo Salines by the application of biocatalysis

Biocatalysis is a field that can bring many options and possibilities to fine chemical industry. Esterases are used as biocatalysts for resolution pharmaceutical intermediates with excellent chemo-, regio- and stereo- selectivity. The microorganism that provides the esterase under study is called MOS-12. This halophilic microorganism was found in the Cabo Rojo Salines (Puerto Rico), with 147 others and it was the most promising enzyme for biotechnological application. MOS-12 was cultured in Marine Broth for 24 hours before running the tests for a complete characterization. The esterase activity was optimized in terms of: salt concentration, temperature, pH and stability in a wide range of organic solvents. In each experiment we used p-nitrophenyl acetate as substrate for esterase activity. The enzyme was purified from culture medium using centrifugation, Ammonium

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Sulfate precipitation, dialysis and lyophilization. The esterase was finally purified and quantified using BCA assay and gel electrophoresis.

Cruz-Lebron, Junellie

Martinez, Osiris - Det. of Chemistry University of Puerto Rico at Humacao ; Lopez, Christian - Dept. of Chemistry University of Puerto Rico at Humacao ; Perez, Krizia - Dept. of Chemistry University of Puerto Rico at Humacao ; Fasoli, Ezio - Dept. of Chemistry University of Puerto Rico at Humacao ; Bansal, Vibha - Dept. of Chemistry University of Puerto Rico at Cayey

Chemistry

Development of new affinity membranes for purification of Plasminogen Activators

Plasminogen activators (PAs) are important therapeutic proteins used as emergency thrombolytic agents for the treatment of thrombovascular disorders such as myocardial infarction and stroke. The separation and purification of these proteins from complex mixtures of cell cultures is a challenging task due to the lack of efficient and suitable processes available. In order to develop a new efficient method for the purification of plasminogen activators, our research was directed towards the development of an effective and accessible affinity membrane-based isolation process that could selectively bind the molecule of interest in a single filtration step. Regenerated cellulose (RC) membranes were chemically modified with spacer arms carrying epoxide or aldehyde moiety which reacted with the hydroxyl moiety of cellulose membrane. Spacer arms of different length (5, 7 and 14 atoms) were tested in order to optimize the process. The spacers were further reacted with two different selective ligands for PAs (para-aminobenzamidine (pABA) and L-Lysine). The modified membranes were characterized in term of epoxide content, ligand density and further used for the purification process. Results showed a 40-fold purification in a single step separation of PA from cell lines HEK-293 conditioned media using these affinity membranes, irrespective of the length of the spacer arm. The system also showed to be very stable and could be reused several times achieving 90% of the PA binding capacity of the membranes even after five cycles of use.

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Cruz-Santiago, Jerameel

Vázquez Pérez R, Orlando - Chemistry, University of Puerto Rico-Mayaguez Campus; De Jesús Echevarría, Maritza* - Chemistry, University of Puerto Rico-Mayaguez Campus

Chemistry

BIOPESTICIDE ACTIVE INGREDIENTS IN JATROPHA GOSSYPIFOLIA L. LEAVES BY HS/SPME and GC/MS

There is an urgent need for the development of alternative insecticides and insect repellents to manage important disease vectors. Jatropha gossypifolia L. belongs to Euphorbiaceae family and some parts of the plant were toxic, as dusts or extracts, to house flies, mosquito larvae, and several species of leaf-eating larvae. The volatile chemical composition of Jatropha gossypifolia L. leaves were identified by gas chromatographic-mass spectrometric (GC-MS) method and headspace solid phase mixcroextraction (HS/SPME). The crushed leaves samples were analyzed at ambient temperature, heated in a hot plate with water and also adding a salt. A total of 56, 100 and 88 volatile compounds were found at ambient temperature, heated in a hot plate with water and heated in a hot plate with water and salt respectively. Around 57% volatile constituents were identifying in the fresh leaves at ambient temperature and 61% using the hot plate with water using the Wiley7 Library Spectral Data Program. A total of 25 compounds were classified as pesticides according to the literature.

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de Jesus-Lozano, Vermary

de Jesus Lozano, Vermary - Chemistry, UPR-CAYEY; Acevedo Robles, Noelia - Biology, UPR-CAYEY; Ospina Millan, Claudia - Chemistry, UPR-CAYEY

Chemistry

Study of the chemical composition and cytotoxic properties of the Puerto Rican Plant Simarouba tulae

Species of the genus Simarouba have been studied because of its antimalarial, antiinflammatory, antileukemic, antifeedant and antiviral activities. A group of highly oxygenated terpenes called quassinoids have been isolated from species of the Simarouba genus and are thought to be responsible for its therapeutic properties. The objective of this study is to isolate and evaluate the biological activity against cancer cell lines of the secondary metabolites from Simarouba tulae, an endemic plant of Puerto Rico. Extracts prepared in our laboratory were preliminary screened using the brine shrimp lethality test. Most of the Simarouba tulae extracts were cytotoxic with LC50 values of <200.00 ?g/ml.. These extracts were further biotested against three breast cancer cell lines (MCF-7, ZR-75-1 and T47D) inhibiting more than 80% of cell growth in two of them. Based in our preliminary results we concluded that these plants showed high anticancer activity and merit a closer investigation of the chemical compounds responsible for the bioactivity. Supported by the Institute of Interdisciplinary Research and the Dean of Academic Affairs of University of Puerto Rico at Cayey

Diaz-Delgado, Miguel

Lopez, Luis - School of Science and Technology, Universidad del Turabo; Nieto, Santander - School of Science and Technology, Universidad del Turabo; Duconge, Jose - School of Science and Technology, Universidad del Turabo; Cotto, Maria - School of Science and Technology, Universidad del Turabo; Marquez, Francisco - School of Science and Technology, Universidad del Turabo

Chemistry

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Synthesis of Single-Walled Carbon Nanotubes to be Used in the Development of Radiation Sensors

Detection of ionizing radiation are crucial in different fields including energy, national security, biological and nuclear research, and other applications. In general, the systems for the detection of ionizing radiation usually have one or several of the following drawbacks: incapability to produce stable signals, expensive and complicated manufacturing processes, operation at low or very low temperatures, low sensitivity or even voluminous size, as is the case of Geiger counters. Single-walled carbon nanotubes, SWNTs, are attracting much attention as promising materials for application in nano-devices due to their excellent electrical conductivity, optical, thermal and mechanical properties arising from their quasi-one-dimensional structure. One of these potential applications is the use of SWNTs as radiation sensor. For this purpose, the critical steps in the design and fabrication of devices are focused on the growth of SWNTs into controlled architectures and onto appropriate substrates. In this research we report a method for the synthesis of vertically aligned SWNTs, based on the use of a mixture of Co and Mo salts as catalyst precursor. In this case, SWNTs are synthesized by CVD, using alcohol as carbon source. The characterization of the synthesized material has been carried out by scanning electron microscopy and Raman. This material is currently being used for the design and development of new sensors for ionizing radiation.

Diaz-Diaz, Elimar

Díaz Cartagena, Diana C. - Chemistry, UPR-Río Piedras; Cunci, Lisandro - Chemistry, UPR-Río Piedras; González, José A. - Biology, UPR-Río Piedras; Washington, Valence - Biology,UPR-Río Piedras; González, Josian - Biology, UPR-Río Piedras; Cabrera, Carlos - Chemistry-UPR-Río Piedras

Chemistry

Impedimetric Detection of Telomerase Activity in Cancer Cells.

Over the last decade, an increasing number of researchers have focused on developing rapid techniques based on biosensor technology for the detection of various human health related conditions. The use of this technology helps to detect early signs of the disease, such as cancer, in a short period of time with high efficiency. The number of cases diagnosed with this condition is increasing throughout the years due to the unhindered growth of abnormal cells partially

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caused by an enzyme called Telomerase. This enzyme activates and elongates telomeres at the end of the chromosomal DNA, which causes cancer cells to become immortal. Telomerase is present in the vast majority of cancer types, therefore, serves as a biomarker. In this work, we developed a DNA biosensor using self-assembled monolayer technique for detection of Telomerase activity in cancer cells. Specifically, we used a robust miniature DNA gold electrode as the sensing platform for the capacitive detection of enzyme binding and DNA elongation processes by Telomerase utilizing Electrochemical Impedance Spectroscopy. We measured changes in the capacitance when the surface was exposed to Telomerase and to a DNA elongation inhibitor. Also, we studied how heat-shock affects the enzyme activity using charge transfer resistance as the sensing parameter. This system provides advantages in terms of simplicity, efficiency and cost of electrode design, and will have a tremendous impact on the biomedical science, filling the absence of methods that can detect Telomerase in a direct readout at the point-of-care location using lab-on-a-chip technology.

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Diaz-Otero, Willda

Rey Santos, Rosamil - Ciencias Naturales y matematicas, UIA Bayamon; Valls, Giancarlos

Chemistry

Identifying Characteristics Of Fibers Using Polarized Light Microscopy

A fiber is the smallest unit of a textile. Fibers can occur naturally as plant and animal fibers, but they can also be man-made. The various analytical methods available for fiber analysis provide us different kinds of information. In forensic sciences textile fibers are considered a trace evidence, because fibers can be transferred during the commission of a crime and this can be used to link people or objects to places, other people or other objects, and often serves as a starting point, or lead, for a particular line of investigation. The type of fiber, their length, and others characteristics that contribute to the diversity of fibers. The morphology of the fiber, their reflectivity, the cross-sectional shape, microscopic characteristics, and other traits of the fiber help us to identify a particular fiber type. This can be seen with an endless number of optical microscopy techniques involving polarized light. In this work Using a polarized light microscope we performed a qualitative description of the following textile fibers such as rayon, polyester, olefin fiber, generic fiber glass, Nylon fiber, Aramid fibers, Modacrylic, Cotton fiber, Acrylic, Saran and Melamine Formaldehyde fiber, was conducted to identify the following physicals characteristics such as morphology, size, surface texture, hardness, reflectivity, transparency, color, magnetism, Refractive index/ indices, pleochroism, dispersion staining, Birefringence, sing of elongation, interference figure, melting point, fluorescence and chemical composition which can be used for comparison and identification of textile fibers.

Dieppa-Matos, Diomedes

Negrón, Luis - Chemistry, UPR-RIO PIEDRAS; Díaz, Tanya - Chemistry, UPR-RIO PIEDRAS; Ortiz, Edwin - Chemistry, UPR-RIO PIEDRAS; Madera, Bismark - Biology, UPR-RIO PIEDRAS; Rivera, José M. - Chemistry, UPR-RIO PIEDRAS

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Chemistry

Organic Nanoflowers Constructed Via Nanogel-Templated Crystallization of Polymers and Proteins

There has been an increasing interest in developing nanostructures (e.g., nanotubes, nanowires, and nanofilms) that mimic biological systems for applications in materials sciences and biomedicine. Recently, nanoflowers, a new type of flower-like nanoparticles, have been developed for applications in catalysis, batteries, drug delivery, and as biosensors. However, many of the methods used to produce inorganic nanoflowers, and also those used to produce the few reported organic nanoflowers, require high temperatures or pressures, expensive equipment, extensive preparation time, were limited to low-scale production, and frequently used toxic reagents. Recently we have developed a physically cross-linked hydrogel template method to grow organic nanoflowers consisting of gel-like mesoglobules called supramolecular hacky sacks (SHS). These SHS are composed of dual-responsive (e.g., temperature and pH) supramolecular G-quadruplexes (SGQs), which in turn are made up of 8-aryl-2’-deoxyguanosine derivatives. We found that by drying SHS containing polymers or proteins (the “seeds”) at mild temperatures (~35 °C), the SHS act as a template for the “germination” of nanoflowers composed from the encapsulated material or “seed” (e.g., dextran-Texas Red, DsRed protein). We have also found that depending on the nature of the “seed” (e.g., identity, molecular weight) and growing conditions (e.g., drying temperature), we can regulate the type of nanostructure obtained (nanoflowers or nanourchins) and the “blooming” of the growing nanoflower. The nanoflower system was studied by scanning electron microscopy, dynamic light scattering, zeta-potential, and confocal fluorescence microscopy. This convenient templated-crystallization methodology is a biocompatible alternative for the development of other complex nanostructures for multiple biomedical applications.

Echevarria-Maldonado, Carlos

Batista Parra, Adalgisa - Chemistry, Pontifical Catholic University

Chemistry

Synthesis of Cathecol Analogs

Catechols are very important bioactive molecules that are being studied in the fields of chemistry and biology. These molecules are used in the industry for the

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synthesis of pharmaceuticals, agrochemicals and antioxidants. Antifungal activity has also been studied in catechols. It is well known that catechols have a major role in biological systems. Catechols participate in the transport of electrons. Because of this characteristic the quinone/hydroquinone capabilities of the catechol is being studied. They are also involved in photosynthesis and cell respiration. Also it has been found that catechols have the ability to interfere with the proliferation of human lymphocyte, production of nitric acid and growth of human cancer lines. It has been found by recent studies that catechols are able to form complexes that can generate organometallic bonds. Industrially cathecol is synthetized primarily by the oxidation of phenol. It can also be obtained by transforming D-glucose with E. coli. The goal of this research is to prepare catechols with different structures. The method to synthesize each catechol analog can vary. Once the catechols analogs have been synthesized the electrochemical behavior of these analogs will be studied. The study will help us have a better understanding of the catechol molecule. In this presentation intent to show the synthesis and characterization de Bis (3,4 dimethoxyphenyl) methanone using as starting materials 3,4 dimethoxybenzoic acid and 1,2 dimethoxybenzene. This compound will be reduced and hydrolyzed to generate a catechol analog called 4,4 methanediylbenzene 1,2 diol.

Encarnacion-Diaz, Paola

Jo Ondrechen, Mary Ph.D - Chemistry and Chemical Biology, Northeastern University; Hanson, Robert Ph.D - Chemistry and Chemical Biology, Northeastern University; Vivoni, Alberto Ph.D - Natural Sciences and Mathematics, Inter American University of Puerto Rico-Bayamon

Chemistry

Computer-Aided Drug Design for Glucocorticoide and Progesteron Receptors

Glucocorticoid and Progesterone Receptors (GR, PR) are steroidal hormones receptors with similar active sites. As a consequence of this similarity, drugs that target one of them also affect the other as well. GR, for example, is a target for immune response regulation and for the treatment of inflammation and of leukemia. PR, on the other hand, is involved in the establishment and maintenance of pregnancy. The drug Mifepristone (RU-486), originally developed for targeting GR, was shown to have affinity for PR and caused the termination of pregnancy. The objective of this project is to develop compounds that have high affinity for one

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receptor but not for the other. This type of research is done with a docking algorithm that calculates a score based on the affinity of a ligand towards its receptor. The YASARA software package is used for this purpose. This package includes a molecular viewer and the AutoDock algorithm. Thus far docking scores for various Mifepristone derivatives have been obtained. Preliminary results will be presented.

Feliciano-Miranda, Yamira

De Jesus Cruz, Pedro R. - Chemistry, University of Puerto Rico at Cayey

Chemistry

Analysis of Volatile Compounds Found in the Valvoline Motor Oil Using SPME and GC/MS

Solid-phase microextraction SPME has demonstrated to be a rapid, low cost, and solvent free extraction technique for organic compounds encountered in aqueous samples. It consists of a holder and a fiber. The fibers are made of fused-silica coated with different polymeric adsorbent materials. The stationary phase can be either polar or no polar. Some of them are composed of carboxen, polydimethylsiloxane, divinylbenzene, polyacrylate, and others. Basically, the SPME fiber is inserted into the headspace of a sealed sample vial where the analytes, i.e. volatile compounds, are absorbed into the fiber until equilibrium is reached. Then, the SPME fiber is inserted and exposed into the gas chromatograph (GC) instrument where the compounds are thermally desorbed and ready for analysis on the mass spectrometer (MS) instrument.

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Figueroa-Cosme, Darinelys

Torres, Wildeliz - Chemistry

Chemistry

Development of a Metallocarbene-based Methodology for the Synthesis of Epoxides

Epoxide moieties are common in natural products and commercial drugs. Moreover, they are often employed as synthetic precursors to various important structural motifs via their regio- and stereoselective cleavage by nucleophiles. Even though numerous strategies have been developed for the construction of epoxides, more efficient methods with lower cost, and minimal waste are still intensively sought after. Asymmetric metal-catalyzed epoxidation of alkenes is probably the most common strategy for the synthesis of optically active epoxides. The addition of metal-stabilized carbenes to aldehydes or ketones has received scant attention. The few published reports use potentially explosive and hazardous diazocarbonyls as carbenoid precursors or expensive rhodium as the metal carbene center. Our goal is to develop an alternate carbene-based methodology for the synthesis of epoxides that uses readily available and safe starting materials. The basis of our method and our efforts to achieve this goal will be presented.

Frias-Flores, Cecilia

Rojas-Perez, Arnulfo - Chemistry Deparment, University of Puerto Rico, Rio Piedras; Diaz-Diestra, Daysi - Chemistry Department, University of Puerto Rico, Rio Piedras; Beltran-Huarac, Juan - Physics Department, University of Puerto Rico, Rio Piedras; Weiner, Brand W. - Chemistry Department, University of Puerto Rico, Rio Piedras; Morell, Gerardo - Physics Department, University of Puerto Rico, Rio Piedras; Diaz-Vazquez, Liz M. - Chemistry Department, University of Puerto Rico, Rio Piedras

Chemistry

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Catalytic Hydrothermal Liquefaction Processing of the Macro-algae Ulva Fasciata

Hydrothermal liquefaction (HTL) is a process that uses high temperatures and pressures for the conversion of biomass into bio-oil. HTL was performed on Ulva fasciata using FeO4 as a catalyst in order to increase the bio-crude yield of the algae. The amount of catalyst added was 50mg, 100mg, 200mg and 300mg. The process took place at 340ºC with a minimum of 60psi and 300rpm. The product of the reaction was separated and each phase was analyzed and quantified using Fourier Transform spectroscopy (FTIR-ATR), Gas Chromatography Mass Spectrometry (GC-MS), Energy Dispersive Spectroscopy (EDS), Scanning Electron Microscopy (SEM) and CHONS analysis. The yield of the bio-crude was increased from 21 to 28.86%wt depending on the amount of catalyst added. The energy recovery was calculated for each sample; it was found that the highest energy recovery for both bio-oil and bio-char of the sample with 100mg was 80.93MJ/kg.

Garcia-Gonzalez, Carlos

Vega, Karlene - Biology, University of Puerto Rico Río Piedras Campus ; Herdocia, Claudia - Biology, University of Puerto Rico Río Piedras Campus ; Robles, Tania - Chemistry, University of Puerto Rico Río Piedras Campus; Nicolau, Eduardo - Chemistry, University of Puerto Rico Río Piedras Campus

Chemistry

Synthesis and characterization of nanocellulose-based nanodiamond coatings for applications in bone tissue engineering

Cellulose nanocrystal fibrils, CNCs, are a novel form of the cellulose polymer, which has the potential to be associated with other substances. Among these, diamond nanoparticles, DNPs, show promise to have chemical versatility due to their biocompatibility and non-cytotoxicity. The synthesis and characterization of these CNCs coupled non-covalently with DNPs were carried out in this experiment. In brief, the CNCs were sililated at its hydroxyl groups to enhance its functionality. Then, non-oxidized DNPs were carboxylated following a strong acids oxidation reaction to yield oxidized DNPs. The effectiveness of the oxidation was verified by comparing TGA, Raman spectroscopy, FTIR, XRD, and SEM results to the original non-oxidized DNPs. Thereafter, the CNCs and oxDNPs were merged non-covalently through sonication. The thermal stability of this new mixture was

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analyzed through TGA and compared to their CNCSi and CNCSi/non-oxDNP analogues. Mixtures of CNCs with oxDNPs and non-oxDNPs showed considerable decomposition starting at 300 °C. Further investigation with oxidized DNPs and CNCSi can entail a covalent union between the carboxyl groups of the oxDNPs and the primary amine of the CNCSi as well as test its biocompatibility with eukaryotic cells.

Gonzalez-Sanchez, Angelica

Ortiz Nieves, Edgardo - Department of Mathematics and Physics, UPR Cayey; Medina, Zuleika - Department of Chemistry, UPR Cayey

Chemistry

The Impact of a Hands-on Activity Incorporating the Threefold Representation on the Liming Reactant Concept

In chemistry students are introduced to complex and abstract concepts and are expected to perceive and comprehend many chemical phenomena and processes. In addition, chemistry can be taught at three levels of representation: macroscopic, submicroscopic and symbolic. Studies suggest that meaningful understanding of chemical concepts is possible by the development of representational competencies, meaning interconnections between the levels of representation. The goal of our study was to investigate the extent to which a hands-on activity, focused on the interplay between the three representations, could affect undergraduate general chemistry students’ performance and interconnection between the levels of representation in the context of limiting reactant. The activity was designed to serve as reinforcement after students are exposed to the limiting reactant topic in class and it allows them to explore this topic from a different and more active perspective. To measure if our objective was reached, an assessment instrument was incorporated as a pre- and post-test for the activity. Preliminary data showed positive results regarding the impact of the activity on students’ understanding of limiting reactant and the interconnection of the three representations. In general, students who participated from the activity had the highest average scores on the assessment and also a higher level of understanding of the limiting reactant topic in comparison to the control group. The results obtained suggest that the applied instructional model represents an effective teaching model.

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Graniela-Marty, Mya

De Jesus Echevarria, Maritza* - Chemistry, University of Puerto Rico-Mayaguez Campus

Chemistry

Volatile Constituents of the Annona reticulata L. fruit from Puerto Rico by HS/SPME and GC/MS

The Annona reticulata L. from the Annonaceae family is considered a pantropical fruit. It is a round fruit with a smooth skin, when ripe it becomes a dull red. A common name for the Annona reticulate L. is bullock’s heart but about this fruit, little has been studied. The volatile composition of the pulp from the Annona reticulate L. from Puerto Rico was investigated by capillary GC/MS and HS/SPME. Two different SPME fibers DVB/Car/PDMS and PDMS/DBV were evaluated. The headspace volatile compounds were identified by comparison of their mass spectra with those in the Wiley7.L MS library. A different volatile composition of the pulp was identified with and without water at room temperature. A total of 85 volatile organic compounds were found in the pulp without water and 77 were found in the pulp with water. In both analyses the main compounds identified were beta-pinene, beta-cubebene, gamma-terpinene, alpha-terpinolene, alpha-terpinene, delta-cadinene, germacrene-D, zingiberene, alpha-gurjunene, alpha-amorphene, beta-bisabolene, 2-butenoic acid, methyl ester, alpha-pinene, benzoic acid, and methyl ester. A comparison of the chemical composition of Annona reticulata L. and the Annona Muricata L. are different, even though they have a sweet similar aroma.

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Lehman-Andino, Ingrid

Montes González, Ingrid - Department of Chemistry, University of Puerto Rico-Rio Piedras

Chemistry

Synthesis, characterization and analysis of symmetric ferrocenyl chalcones derivatives

Symmetric and non-symmetric ferrocenyl chalcones derivatives captivated the scientist's attention with its numerous uses and applications such as, biofuel cells, biosensors, optoelectronics, drug delivery systems and as topoisomerase II? inhibitors. These ferrocenyl chalcones properties promise treatments to human diseases, and as synthetic precursors for other biological active compounds. Our interest is primarily focused on symmetric ferrocenyl chalcones that exhibit remarkable stability in their structure and excellent biomedical properties. By applying a solvent free approach to the Claisen–Schmidt reaction, twelve new symmetric ferrocenyl chalcones from 1,1-diacetylferrocene has been synthesize in moderate to good yields and short reaction times. We have characterized these compounds by spectroscopic techniques (NMR, IR, UV/visible) and some of them by X-Ray crystallography. Moreover, we have conducted a study of their electrochemistry. The synthetic methodology, characterization, and results of preliminary bioassays of these compounds will be elaborated. Work supported by Pfizer Pharmaceutical and MARC program.

León-Feliciano, Isannette N.

Alamo Nole, Luis - Department of Chemistry, Pontifical Catholic University of Puerto Rico-Ponce; Perales Perez, Oscar - Department of Engineering Science and Materials and Department of Chemistry, University of Puerto Rico - Mayaguez; Roman, Felix R. - Department of Engineering Science and Materials and Department of Chemistry, University of Puerto Rico - Mayaguez; Bailon Ruiz, Sonia - Department of Chemistry and Physics, University of Puerto Rico-Ponce

Chemistry

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Photodegradation of antibiotics in aqueous solutions using Quantum Dots of Cd(Se,S)

Daily basic drugs and antibiotics used by people found in municipal waste can cause detriment effect to exposed ecosystems. The traditional wastewater treatments fail to remove these new contaminants when they are at low concentrations. Quantum dots of CdSe(S) synthesized under microwave irradiation were used as photocatalyst to eliminate tetracycline (TC) and oxytetracycline (OTC) (under UV irradiation at 302 nm) in aqueous phase at pH 6.5. Quantum dots were characterized by X-ray diffraction (XRD), UV-Vis and photoluminescence (PL). The degradation of TC and OTC were monitored using High Performance Liquid Chromatography (HPLC) at 355 nm. The photodegradation efficiency was dependent on the Quantum Dots concentration.

Luciano-Irizarry, Richard

Santos Santori, Lizette - Chemistry, Pontifical Catholic University of Puerto Rico

Chemistry

Determination of the bio-sorbent properties of the Neem tree (Azadirachta indica) in CHO cells by ICP-OES and HPLC

Cadmium is a toxic soft metal which can cause different diseases. The health distress will depend on the concentration, the oxidation state, and exposure to this metal. At different concentrations the effect will vary. Cadmium species can produce severe respiratory problems, it can generate reactive oxygen species (ROS), cell proliferation, autophagy, apoptosis, and other threats. In this study, Chinese Hamsters Ovarian cells (CHO) will be exposed to cadmium acetate to induce cell proliferation. The colonies will be treated with neem (Azadirachta indica) tree extracts to study the recovery of cadmium in biological systems, based on the covalent bond with the biological ligands of the tree extracts. CHO cells and their medium will be analyze to quantify the concentration of cadmium and determine the bio-sorbent properties of the tree extracts. The metal uptake will be analyzed by inductive coupled plasma optical emission spectrometry (ICP-OES) and high performance liquid chromatography (HPLC).

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Lugo-Diaz, Ghiara

Cruz, Leishla - Universidad de Puerto Rico en Mayagüez; Robles, José - Universidad de Puerto Rico en Mayagüez; RIvera Portalatín, Nilka - Universidad de Puerto Rico en Mayagüez

Chemistry

Characterization of Petiveria Allicea cytotoxic activity, antioxidant and anticancer properties in brine shrimp models

Isolation of active ingredients from medicinal plants are known to play an important role in the identification of lead compounds that can help in the development of new, effective and safer drugs to treat cancer. Evidence suggests that the tropical plant Petiveria alliacea has anti-proliferative properties against several cancer lines. In an effort to identify active metabolites from this plant that could be used as lead compounds for the development of new anti-cancer drugs, the cytotoxic activity of the tea prepared from the leaves has been evaluated. Briefly, the tea is prepared, and the compounds extracted are submitted to separation by column chromatography. The antioxidant properties of the fractions have been determined and their toxicity against brine shrimps has been evaluated using the Brine Shrimp Lethality Bioassay. The results are reported in terms of LC50 and the most active fractions have been submitted to cytotoxic studies using colon cancer cells. Correlations between the antioxidant capacity and bioactivity with anticancer properties have been established and will be presented. In conclusion, this study provides evidence that the tea obtained from Petiveria Alliacea could have therapeutic implications not only for cancer but probably for other diseases caused by oxidative stress.

Martinez-Cardenas, Maria

Pérez, Wanda - Department of Chemistry, University of Puerto Rico - Mayaguez Campus; Soto, Yarelys - Department of Biotechnology, University of Puerto Rico - Mayaguez Campus; Ortiz, Carmen - Department of Pharmacology, Toxicology and Physiology, Ponce School of Medicine and Health Sciences; Matta, Jaime - Department of Pharmacology, Toxicology and Physiology, Ponce School of Medicine and Health Sciences

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Chemistry

Genotoxic effects of ferrocene derivatives by Cytokinesis-block micronucleus assay (CBMN) on tumorigenic breast cancer cell line (MCF7)

Ferrocene and ferricenium are commonly used to synthesize drugs for chemotherapeutic treatment. For many years, researchers have driven their attention to functionalization of ferrocene or ferricenium complexes to increase their toxicity and genotoxic damage in tumorigenic breast cancer cells (MCF7). It is well known that metallic compounds based on ferrocene or ferricenium caused direct damage to DNA. Ferrocene complexes produce reactive oxygen species (ROS) that lead in chromosome breaking. In this study the genotoxic damage of new ferrocene derivatives were assessed by Cytokinesis-block micronucleus assay (CBMN). A measure of DNA damage was calculated based on micronuclei formation. Micronuclei are extranuclear chromosome fragments expressed on divided cells and they measure the amount of DNA damage. For CBMN assay, the compounds previously synthesized, 1,1’-4-(1H-pyrrol-1-yl)phenyl ferrocenedicarboxylate, (“Fc-(CO2-Ph-4-Py)2”), 1,4-(1H-pyrrol-1-yl)phenyl, 1’-carboxyl ferrocenecarboxylate (“Fc-(CO2-Ph-4-Py)CO2H”) and 4-(1H-pyrrol-1-yl)phenyl ferroceneacetylate (“Fc-CH2CO2-Ph-4-Py”) were exposed to the cells for 72 h. The cells were then treated with cytochalasin-?, a filament inhibitor of the cytokinesis in cells, to obtain binucleated cells which could express the micronuclei forming activity. The studies revealed that the presence of these substances induce micronucleus formation in binucleated cells and that Fc-(CO2-Ph-4-Py)2 exhibits a higher micronucleus formation compared with the other complexes studied.

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Martínez-Marquez, Francisco

Casañas, Bárbara - Chemistry,UPR-RIO PIEDRAS; Agosto, José - Biology, UPR-RIO PIEDRAS; Giray, Tugrul - Biology, UPR-RIO PIEDRAS

Chemistry

Intercalation and chemical characterization of two neurochemical species in zirconium phosphate layers for drug delivery application

Zirconium(IV) bis(monohydrogen phosphate) hexahydrate is a highly hydrated phase of zirconium phosphate (ZrP), known as the 10.3 Å phase. ZrP is a layered inorganic compound and throughout the years many applications have been developed based on this material. The purpose of this research involved the intercalation and characterization of both dopamine (DA) and carbamazepine (CBZ), into the 10.3 Å phase of ZrP to study the use of the layered material as a potential host for drug delivery and other biomedical applications. One of the most important neurotransmitters in the brain is dopamine. While carbamazepine functions as an anticonvulsant and mood stabilizing drug to treat various neurodegenerative diseases.. One of the major problems about DA and CBZ is that they are photosensitive and easily degraded. The intercalation into ZrP layers would provide a stable environment that will protect and help deliver both compounds to their corresponding targets. The intercalation procedure of DA was performed at two different pH levels at a drug:ZrP molar ratio of 5:1, aqueous solution. Upon intercalation a new expanded phase of ZrP was obtained with an interlayer distance of 10.5 Å at a pH equal to 8. The intercalation procedure for CBZ was performed as well at a molar ratio of 5:1 in two different solvents. Upon intercalation a new expanded phase of ZrP was obtained with an interlayer distance of 10.0 Å, with the use of acetonitrile as the solvent. These results suggest that both compounds were successfully intercalated within ZrP layers. The characterization of both compound-intercalated products using Fourier Transform-Infrared spectroscopy (FTIR), UV-vis spectrophotometry, and energy dispersive X-ray spectroscopy (EDS) will be presented as well. Further studies will corroborate if ZrP is a suitable material for the intercalation of both dopamine and carbamazepine.

Medina-Berríos, Nataniel

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Gonzalez, Gellyz - Chemistry, UPR-RIO PIEDRAS

Chemistry

Bulk synthesis of TCNQ anion radical salts and derivatives: development of paramagnetic linkers.

TCNQ, 7,7,8,8-tetracyanoquinodimethane, is an organic electron accepting molecule considered to be a potential building block for the development of more efficient supramolecular magnets since it forms many powerful semiconductors with a large number of countercations. Four previously published methods for the bulk synthesis of TCNQ radical anion salts were analyzed with the objective of determining the most adequate route for synthesizing TCNQ radical anion salts: complexation of TCNQ with nickel in a water sensitive reaction, reduction via an electrolytic cell, synthesis of alkali-TCNQ salts via CVD in textiles and reduction of TCNQ in a reaction with 1,10-phenanthroline and hydroquinone. Each synthesized bulk of TCNQ radical anion salts will be used for the development of new paramagnetic linkers with greater magnetic response. The first paramagnetic linker to be synthesized is an union between TCNQ monoanionic and the organic paramagnetic radical cation salt Nitronyl Nitroxide-Substituted 5,10-Diphenyl-5,10-dihydrophenazine as its countercation. Effectiveness of the methods of TCNQ radical anion salt production are to be compared by yields, cost of production, quantities of reactants used, number of steps in the synthetic route, speed of reaction and quality of the products. The first method analyzed was the reduction of TCNQ via a water-sensitive complexation reaction with nickel, producing a green solution with a bluish precipitate that responded to an applied magnetic field. Product was characterized via UV-Vis spectroscopy and its solubility was tested, resulting in the product being the nickel and TCNQ complex, lacking solubility in any available solvent, making the solid unfit for recrystallization.

Miranda-Belandria, Marco

Feliciano, Marangeli - Science and Technology, Univerdad Interamericana de Puerto Rico Reciento de Ponce; Medina, Eulalia - Science and Technology, Univerdad Interamericana de Puerto Rico Reciento de Ponce; Ramirez, Jose - Science and Technology, Univerdad Interamericana de Puerto Rico Reciento de Ponce; Osorio, Celia - Science and Technology, Univerdad Interamericana de Puerto Rico Reciento de Ponce

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Chemistry

Functionalization and characterization of bimetallic silver-gold nanoparticles with antibiotics

New methods for drugs detections are necessary to improve the time and sensitivity for drug testing. Our work is focused in the development of a strategy to produce bimetallic silver-gold nanoparticles for the study of drugs interactions. Formation of the nanoparticles was achieved by the double reductions of the AgNO3 and HAuCl4 with polyethylene glycol, sodium citrate, hydrogen peroxide and sodium borohydride. This technology offers minimization of reaction times and stabilization of nanoparticles. In this research, we explore the interactions with Penicillin, Ciprofloxacin, Vancomycin and Clindamycin with the bimetallic silver-gold nanoparticles. Characterization of the nanoparticles was performed using UV-Vis absorption spectroscopy with a band absorption center at 523 nm, Diffracted Light Scattering (DLS) study shows a mean diameter of 46.1 nm. Interaction with antibiotics results in a red shift between 15-70 nm. Also a change in color is produced with the addition of the antibiotics to the bimetallic nanoparticles.

Molina-Villarino, Andres

Montes, Ingrid - Chemistry, University of Puerto Rico, Río Piedras Campus

Chemistry

Thiosemicarbazone-derivatives from Ferrocenyl Chalcones as Potential Antibacterial and Antimalarial Agents

Organic chalcones are considered to be natural occurring products. They are known to exhibit a broad range of biological activities, including antimalarial, antibacterial, and anticancer activity. Replacing one of the aromatic rings of a chalcone with a ferrocenyl group results in what is known as a ferrocenyl chalcone. These organometallic compounds may present greater biological activity than their organic analogues, presumably due to the lipophilicity of the ferrocenyl group and resulting bioavailability. Other chalcone derivatives also tend to exhibit greater biological activity than their corresponding chalcone core, as is the case for chalcones containing the thiosemicarbazide group. For these reasons, this research is focused on the synthesis of Thiosemicarbazone-derivatives from ferrocenyl chalcones, with the idea to combine both known “bioactivity-enhancers” in one

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single chalcone. We pursue three specific aims: develop an efficient methodology for the synthesis of the derivatives, characterize them by spectral and electrochemical analyses, and test them in collaborative-based biological assays for malaria and a series of bacteria. For the moment, a series of ferrocenyl chalcones containing different substituents, 1-Fc: o-Cl, m-Cl, p-Cl, o-OMe, m-OMe, p-OMe; 3-Fc: o-Cl, m-Cl, p-Cl, o-OMe, m-OMe, p-OMe, m-F, p-F, have been synthesized, with moderate to good yields. Most can be purified via recrystallization over ethanol, while others require column chromatography. The prepared chalcones will be used as starting material, along with thiosemicarbazide, to produce the desired thiosemicarbazone-derivatives. The synthetic methodology and characterization of these compounds will be elaborated.

Morales-Garcia, Victor

De León Cruz, Sabrina - Department of Chemistry, University of Puerto Rico; Rivera, Luis A. - Department of Chemistry, University of Puerto Rico; Cox, Osvaldo - School of Environmental Affairs, Universidad Metropolitana, San Juan, Puerto Rico

Chemistry

Synthesis and Characterization of 2-Methyl-1-phenylmethyl[1,4-dioxane][2,3-f]- and 2-Methyl-1-phneylmethyl-[1,3-dioxole]-1H-benzimidazole as the Precursors for the Synthesis of 3-nitro- and 3-amino-7-benzyl-9,10-[1,4-dioxan]- and 9,10- [1,3-dioxole]benzimidazo[3,2-a]quinolinium chloride salts

Benzazolo[3,2-a]quinolinium salts (BQS) are unnatural alkaloids with structural similarities to the well-known benzo[c]phenathridine and ellipticine natural products. They are polyciclic aromatic systems with known anticancer and antimicrobial activities. Recently it has been discovered (Zayas, Cox US Patent 8,124,770 B2, February 28, 2012) that amino substituted BQS potentially useful as fluorescent cellular markers. The rationale and motivation of this project is to design and synthesize new molecules where the basic BQS scaffold is modified to produce new more effective products and to investigate their potential antitumor activities as well as their molecular mode of action. The key step toward the preparation of the modified BQS is 2-styryl-1-benzylbenzimidazole (1), which was prepared in 7-steps starting with 1,4-benzodioxan-6-amine or 1,3-benzodioxole-6-amine. The reaction sequence commences with acetylation to yield the respective acetamide, which

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was then nitrated to yield a nitroacetamide, which upon basic hydrolysis affords the respective nitroaniline, which is then benzylated, followed by chemical reduction of the nitro group affording 2-amino-4,5-(1,4-dioxan)- or 2-amino-4,5-(1,3-dioxole)-N-benzylaniline, which is acetylated followed by cyclocondensation in acid to yield 1.

Munoz-Forti, Kevin

Robert Renthal

Chemistry

Kinetic Mechanism of Lipidprotein Nanodisc Dissociation in Bicelles

Nanodisc soluble lipid bilayer systems are vital in rendering membrane proteins soluble in aqueous solutions where they remain monodisperse and active in a membrane-like environment. Nanodiscs or nanolipidprotein particles (NLPs), are bordered by an amphipathic helical protein belt or membrane scaffolding protein (MSP) mimicking a cell membrane. Past works have shown that fragments of bacteriorhodopsin when placed in separate nanodisc do not interact to form the functional protein. The introduction of bicelles enabled the fragments to form oligomers inside the bicelles. An analysis of the kinetics of the aforementioned NLP-bicelle interaction showed a sigmoid curve suggesting the possibility of an autocatalyzed reaction. We hypothesized that the kinetics where due to MSP1E3D1's dissociation from the nanodisc which catalyzed the reaction. Using fluorescently labeled lipids 1,2-dioleoyl-sn-glycero-3-phosphoethanolamine-N-(lissamine rhodamine B sulfonyl), 1,2-diphytanoyl-sn-glycero-3-phosphoethanolamine-N-(7-nitro-2-1,3-benzoxadiazol-4-yl) LR-PE and NBD-PE, respectively with 1,2-dimyristoyl-sn-glycero-3-phosphocholine (DMPC) and MSP1E3D1 we constructed NLPs. Bicelles were prepared using 1,2-dihexanoyl-sn-glycero-3-phosphocholine (DHPC) and DMPC. Kinetics of NLP-bicelle interactions and fluorescently labeled lipid dispersion were observed measuring fluorescence resonance energy transfer (FRET) using stopped-flow spectroscopy. The NLP-bicelle interaction followed previously observed kinetics and continued to do so after the addition of excess MSP1E3D1. Our results show that MSP1E3D1 is not responsible for the observed kinetics of the transfer of lipids between NLPs and bicelles.

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Negron-Pineiro, Lenny

Qu, Wanlu - Chemistry and Chemical Biology, Northeastern University; Zhou, Zhaohui - Chemistry and Chemical Biology, Northeastern University

Chemistry

Expression and Purification of Homocysteine Methyltransferase Sam4 Recombinant in Escherichia coli

It is well known that, in organisms, one of the functions of enzymes is to avoid the accumulation of bioorganic compounds that can inhibit biological processes indispensable for cell function. Recently, it has been found that organisms such as yeast, fruit flies, nematodes and plants use a methyltransferase enzymes to convert isomer R-Adenosyl-L-methionine to its bioactive form S-adenosyl-L-methionine. Particularly, yeast employs two homocysteine methyltransferase Sam4 and Mht1 to deplete R-AdoMet accumulation. In humans, the processes or enzymes that carry out the conversion of R-AdoMet to S-Adomet are still elusive. Therefore, the focus of the study was to express and purify recombinant Sam4 in Escherichia coli by immobilized metal affinity chromatography, respectively. First, the method was applied to the recombinant human thiopurine methyltransferase protein and the method results effective since a high yield and reproducible purification was observed. TPMT catalysis shows that a methyl transfer to aromatic thiols occurs in a time and enzyme concentration dependent manner. Sam4 expression was performed successfully, but the purification was partially effective. Consequently, the study of the enzymatic capacity of Sam4 shows a minimum activity at the condition employed. The results imply that the purification method should be refined. The affinity purification can be optimized in Sam4 studies to fully understand and decrypt the enzyme mechanism and functions in vivo, to detect substrates that are catalyzed by it, and to elucidate the physiological response of R-AdoMet bioacumulation.

Negrón-Quintana, Frances

Díaz, Tanya L. - UPR-Río Piedras; Rivera, José M. - Department of Chemistry, UPR-Río Piedras

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Chemistry

Studies of the Immunomodulatory Activity Using a Library of 8-Aryl-2'-deoxyguanosine derivatives

Toll-like receptors are type I transmembrane proteins that play a key role in the immune response system when it recognizes invading pathogens. Up to date, 10 TLRs have been identified in humans and in this study we will focus on TLR7 and TLR8. Signaling malfunctions in these pathways can lead to diseases, for which reason researchers have taken interest in studying the response TLRs have towards different agonists. As found in previous studies, TLR7/8 are endosomal and have similar structures and composition, sharing leucine-rich regions. Both TLR7/8 recognize single-stranded RNA – and the imidazoquinoline family of heteroaromatics, but only TLR7 is activated by guanosine derivatives. Based on the evidence about the interactions of these compounds and the TLR7/8, we will test some 8-Aryl-2 -deoxyguanosine derivatives developed in our laboratory as agonists for TLR7. Our strategy will rely on the use of HEK-293 cells genetically modified to express TLR7, as proven before by other researchers. Specifically, we will present the results using the commercially available TLR7 activation cell-based HEK Blue assay to screen a library of 8ArGs. This assay provides an indirect measure of the level of activation of TLR7 by identifying the activation of NF-kB, which in turn produces secreted embryonic alkaline phosphatase, known as SEAP, and generates a blue color that is conveniently measured using a microplate reader. These results should enable the development of new immunotherapeutic agents for the treatment of a variety of infectious diseases and cancer.

Padilla-Mercado, Jeralyne

Ortiz-Nieves, Edgardo L. - Mathematics and Physics, University of Puerto Rico at Cayey; Ortiz, Jeanell - Chemistry, University of Puerto Rico at Cayey; Medina, Zuleika - Chemistry, University of Puerto Rico at Cayey

Chemistry

The Use of the Three Levels of Representation on the Instruction of Buffers

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Chemistry students at lower- and upper-levels struggle understanding chemistry concepts and solving problems related to the concept. Buffer is one of the concepts that students encounter difficulties creating incomplete or incorrect symbolic representations graphically, making the connection between the three levels of representation (macroscopic, sub-microscopic and symbolic), and representing the phenomena submicroscopically. To help students with these difficulties a hands-on activity that incorporates the three levels of representation was developed. The goal of the study was to determine the impact that the hands-on activity had in undergraduate general chemistry and physical chemistry students. The answers to questions they worked during the hands-on activity were analyzed to investigate if the hands-on activity helped them with the difficulties they encounter with buffers. In addition, students’ responses to the questions were classified using Bloom’s taxonomy to compare both populations in terms of cognitive process. Students’ ideas about buffers in the three representations, their misconceptions, and the types of support students need to understand buffers and solve buffer problems will be discussed.

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Pagan-Sostre, Brandon

Perez-Gonzalez, Marianita - Department of Chemistry, University of Puerto Rico - Rio Piedras; Velez-Pereira, Roberto J. - Waters Technologies; Lee, Ching Chin - Department of Chemistry, The University of the West Indies – Mona; Rosario, Osvaldo - Department of Chemistry, University of Puerto Rico - Rio Piedras; Minott-Kates, Donna A. - Department of Chemistry, The University of the West Indies – Mona; Diaz-Vazquez, Liz M. - Department of Chemistry, University of Puerto Rico - Rio Piedras

Chemistry

Analysis of Hypoglycin A in Ackee fruits (Blighia sapida) by derivatization with 6-aminoquinolyl-N-hydroxysuccinimidyl carbamate (AQC)

Hypoglycin A (Hyp-A) is a toxic compound found in Jamaican ackee fruits. Its concentration in the edible portion of the ackee fruit decreases during the maturation process to levels safe for human consumption. Analysis of Hyp-A in processed products is conducted to establish their safety. The assay of Hyp-A is normally conducted by derivatizing with phenyl isothiocyanate (PITC) followed by High Performance Liquid Chromatography (HPLC) with UV detection. PITC derivatization is a multi-step process that is time consuming and generates complicated chromatograms arising from side reactions. Hence, simpler and stable methods of analyses are desirable. A faster and simpler derivatization using 6-aminoquinolyl-N-hydroxysuccinimidyl carbamate derivatization (AQC) and analysis by Ultra Performance Liquid Chromatography (UPLC) with UV detection is being studied. AQC derivatization can be completed in approximately 15 minutes and its chromatogram has considerably fewer peaks. Both reactions have a good linear response for the analysis of Hyp-A. Preliminary results have shown that AQC derivatized Hyp-A is much more stable than PITC without the need for refrigeration. AQC derivatized Hyp-A varies very little in a 5-day period and it is stable at day 20. PITC derivatization stability over time showed variations in response over the first 5 days of analysis and a slight variation in day 20. AQC and PITC derivatized Hyp-A methods by UPLC analysis are being evaluated for their stability, limit of quantization and their performance in the analysis of real samples.

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Pellicier-Rodriguez, Carolina

Feliciano Sanchez, Marangelie - Inter American University of PR, Ponce, Puerto Rico, United States; Medina, Eulalia - Inter American University of PR, Ponce, Puerto Rico, United States; Ramirez Domenech, Jose - Inter American University of PR, Ponce, Puerto Rico, United States; Osorio Cantillo, Celia - Inter American University of PR, Ponce, Puerto Rico, United States; Ferrer Torres, Edmy - Inter American University of PR, Ponce, Puerto Rico, United States

Chemistry

Synthesis and comparative study of ZnO/Au, ZnO/Ag, MgO/Au, and MgO/Ag core-shell nanoparticles with their functionalization with antibiotics

Core-shell nanoparticles is significant due to their highly functional applications in modifying antibiotic properties. This work is focuses in the development of a simple strategy to produce ZnO/Au, ZnO/Ag, MgO/Au and MgO/Ag core-shell nanoparticles. For the gold shell formation we used HAuCl4·3H2O and AgNO3 for the silver shell formation. Optical properties and characterization of the core-shell was performed by using UV-Vis absorption Spectroscopy and Diffracted Light Scattering DLS. The size of the ZnO nanoparticles was 35nm, and the core-shell obtained was 270nm for ZnO/Au and 285nm for ZnO/Ag. The size of the MgO nanoparticles was 68nm, and the coreshell obtained was 261nm for MgO/Au and 278nm for the MgO/Ag. Vancomycin and Penicillin antibiotics were used for interaction with core-shell nanoparticles. UV-Vis analysis showed new peaks formation between 275nm to 300nm. Subsequent additions of 20?l up to 180?l total of antibiotics had an increase uptake. Red shift in the 275 nm band absorption occurred for 200-420?l additions; where the peak became sharpened. DLS analysis showed a good polydispersity index indicating uniformity of the sample.

Perez-Roman, Astrid

Betancourt, Luis E. - Chemistry, UPR Rio Piedras; Cabrera, Carlos R. - Chemistry, UPR Rio Piedras

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Chemistry

RoDSE electrodeposited Au on unsupported Carbon Vulcan XC-72 for Ethanol Oxidation in Alkaline Media

The development of a robust electrodeposition method consisting on novel technique called Rotating Disk Slurry Electrode (RoDSE) was employed to obtain Au nanoparticles dispersed on a highly conductive carbonaceous support (Vulcan XC-72R) for ethanol electrooxidation in alkaline media. The RoDSE method to obtain highly dispersed Au nanoparticles does not require the use of a reducing agent or surfactant and the precious metal loading can be tuned by the addition of metal precursor volume. Parameters such as applied reduction potential, time of electrodeposition, concentration of precursor and revolutions per minute of the working electrode were optimized in order to obtain a highly active and stable Au catalyst. Physical characterization consisted on thermogravimetric analysis to determine metal loading, X-ray diffraction to determine crystal symmetries and transmission electron microscopy to determine morphology of the synthesized catalyst. Electrochemical characterization consisted on Cyclic Voltammetry and Chronoamperometry on ethanol in alkaline media to determine activity and stability of the catalyst.

Quinones-Diaz, Blanca

García, Jennifer - Chemistry Department, University of Puerto Rico-Humacao

Chemistry

Synthesis of Chiral Oxetanes via the Enantioselective Reduction of Prochiral 2-Halogenated Ketones

The enantioselective reduction of prochiral 2-halogenated ketones is a practical and effective way to synthesize nonracemic halogenated alcohols, which can be transformed into enantiopure oxetanes. The ring opening of oxetanes with amino compounds can produce a variety of optically active amino alcohols, which are key precursors in the synthesis of biological active compounds, particularly, for the treatment of neurological diseases, such as depression and anxiety. Our work is based on the asymmetric borane–mediated reduction of prochiral ?-halogenated aryl ketones to their corresponding optically active alcohols using as catalyst the spiroaminoborate ester derived from ethylene glycol, triisopropyl borate and (S)-(-)-

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diphenyl-2-pyrrolidinemethanol. The enantiopure alcohols were purified by column chromatography with silica gel and characterized by NMR, IR, GC/Chiral Column and GC/MS. The cyclization of the nonracemic alcohols to form the oxetane was successfully achieved using 3 equivalents of potassium tert-butoxide as base, obtaining the oxetane in excellent yield.

Ramirez-Santiago, Lenianne

López Collazo, Anthony - Microbiology ; Pellicier Rodríguez, Carolina - Biology; Ferriol Alonso, Alvaro - Biotechnology ; Domenech Ramírez, Jose - Biology; Osorio Cantillo, Celia - Chemistry; Ferrer Torres, Edmy - Chemistry

Chemistry

Comparative study and characterization of MgO, ZnO, and CuO nanopartciles using amino acids as capping agents.

Synthesis of ZnO, MgO and CuO nanoparticles was done using sonochemical method. Colloidal powder nanoparticles were obtained using zinc sulfate hydrate, magnesium chloride and copper sulfate as zinc, magnesium and copper sources respectively. Tetra methyl ammonium was employed as a surfactant. Polyvinyl alcohol (PVA) and Polyenthileneglycol (PEG) were used as stabilizers. Characterization, following synthesis, was done using optical spectroscopy (Ultraviolet Spectroscopy), Infrared spectroscopy (FT-IR) and diffracted light scattering (DLS). Kinetics studies were done to further information on nucleation and growth. These studies include changes in: reactants concentrations, sonication time and titration rate and heating time. Optical studies show the formation of the clusters and the nanostructures. The size of the nanoparticles was obtained using DLS. The size distribution was 34nm for ZnO, 68nm for MgO and 14nm for CuO. The absorption bands for the nanostructures formation were centered in 358nm for ZnO nanoparticles, 600nm for CuO nanoparticles and 335nm for MgO nanoparticles. The ZnO nanoparticles and MgO nanoparticles was stabilized using cysteine and methionine amino acids. New studies using CuO and lysine were performed.

Ramos-De Dios, Stephany

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Montes, Ingrid - Otaño, Myrna

Chemistry

Synthesis of the nonsymmetric ferrocene derivatives from 1,1’-diacetylferrocene

Ferrocene, is an organometallic compound that exhibits multiple medicinal applications due to its great stability. Ferrocene derivatives are compound that have an ?,? – unsaturated ketone system have been named as ferrocenylenones. They have gained prominence as a new generation molecular materials, ?-conjugated multi-metallic systems, and as redox-switchable receptors. Some of its characteristics are neutrality, chemical stability, non-toxicity and ability to cross cell membranes giving a wide potential of biological activity. Non-symmetrical ferrocene derivatives have the potential of enhancing the biological applications and activity. For example, unique functional groups on each ring have been used to assemble electroatractive peptide and DNA conjugates. It has been reported that a mixture of products: non-symmetric chalcone, di-chalcone and ferrocenophone is obtained when of 1,1’- diacetylferrocene undergoes Claisen-Schmidt reaction. This research is focused on developing an efficient methodology to selectively promote the formation of a desired product (non-symmetric ferrocene derivative) in the condensation of the 1-1'- diacetylferrocene. Until now we have found that variation of temperature, solvent, stoichiometry and substitution of the benzene ring influence the ratio of the desire product. The synthetic methodology and characterization of these compounds will be elaborated.

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Ramos-Garces, Mario

Julissa González - Chemistry Department, University of Puerto Rico-Río Piedras; Jorge Colón - Chemistry Department, University of Puerto Rico-Río Piedras

Chemistry

Cointercalation of Doxurubicin and Cisplatin in Zirconium Phosphate Nano-platelets as a Delivey Agent for Combination Chemotherapy

Two common drugs used in the treatment of cancer patients are doxorubicin and cisplatin. Doxorubicin works by insertion in the DNA disturbing the function of Topoisomerase II avoiding the DNA transcription and consequently the replication process in cancer cells. On the other hand, cisplatin binds to the N-7 sites of guanine bases in DNA forming DNA-protein and DNA-DNA interstrand and intrastrand crosslinks which causes DNA damage activating transduction pathways leading to cell apoptosis. These drugs cause acute side effects to human health. We have previously demonstrated both the ability of intercalating cisplatin into nanoplatelets of the layered inorganic compound zirconium phosphate (ZrP) and doing the same with doxorubicin. The objective of this project is to develop a drug delivery system for combination chemotherapy by cointercalating doxorubicin and cisplatin in nanoparticles ZrP to kill cancer cells more efficiently and selectively by taking advantage of the enhanced permeability and retention effect (EPR). The phase of ZrP being used is ?-ZrP in which the interlayer distance is 10.3 Å. The products of these cointercalations have been characterized by X-Ray powder diffraction (XRPD), infrared spectroscopy (IR), scanning electron microscopy with energy dispersive X-ray spectroscopy (SEM-EDS) and X-ray photoelectron spectroscopy (XPS). The diffraction pattern obtained shows a peak at ~10.6 Å corresponding to the second order diffraction peak of doxorubicin. This indicates the presence of this drug in the ZrP layers and also possibly the presence of cisplatin since the dimensions of this drug are smaller. SEM-EDX and IR spectra corroborate the presence of cisplatin.

Rios-Gonzalez, Celeny

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Rios, Celeny - Science and Technology Depaertment, Interamerican University of Puerto Rico

Chemistry

Antimicrobial Properties of Copper

Copper is an important metal that is distributed throughout nature and whose discovery dates from around 5000 BC. Pure copper is soft and malleable; a freshly exposed surface has a reddish-orange color. It has been used in a variety of applications ranging from construction of household utensils, clothing accessories and even as an electric conductor. History has shown a health related use for copper in ancient civilizations. Copper is a powerful antimicrobial with proven rapid, board spectrum efficacy against pathogens threatening public health and wire community. On this study, we want to evaluate and compare, at two different times, the effect of solid copper on Staphylococcus aureus and Enterobacter aerogenes. The antibacterial effect of copper will be compared with plastic and stainless steel. Our results show that copper inhibits the three tested bacteria at 1 and 3 hours of exposure. Copper surfaces showed complete inhibition of growth in contrast with the effect observed in plastic and stainless steel. We also tested, using S. aureus and Pseudomonas aeruginosa, the antibacterial effect of copper in solution. Inhibition of copper was observed on S. aureus at a concentration of 15 ug/ml. Our results demonstrate the antibacterial properties of copper on bacteria of medical important. Solid copper is more effective inhibiting growth of bacteria than copper in solution. Further studies are required to test more concentrations of copper in solution and other strains of the tested bacteria.

Rivera-Lopez, Gretchen

Barletta, Gabriel - Department of Chemistry, UPR-Humacao

Chemistry

Non-toxic and stable iron oxide-carriers for delivering an antitumor agent in vivo

Introduction: In vivo targeted delivery of short interfering RNA (siRNA)-based therapeutics is an important, but currently challenging, aspect of the drug

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development process for many diseases, including cancer, viral infections, and autoimmune and neurodegenerative disorders. Our goal is to develop a drug delivery system to improve targeted therapies for human disease. Our objective is to develop optimized Super-Paramagnetic Iron Oxide carriers (SPIONS) that can successfully deliver siRNAs to target tissues. These carriers consist of an iron oxide core covered by a modified polyethylenimine shell. Their efficiency will be evaluated using two in vivo models: Drosophila melanogaster and the mouse. The central hypothesis is that SPIONS designed with modified poly(ethylene imines) (PEI) will yield maximal delivery of siRNA molecules to targeted tissues in vivo. Method: Different SPIONS were tested in cell lines for their transfection efficiency of firefly luciferase (GL2 + GL3) siRNA. We also explored the benefits of magnetofection. Drosophila was successfully used to assess the SPIONS toxicity and their effects on the flies circadian rhythm. Results: Reducing the polyctionic character of the nanoparticles eases their toxicity while maintaining their high transfection efficiency, which is increased by magnetofection. The circadian rhythm of Drosophila melanogaster was affected, and a dependence on the SPIONS surface groups was observed. Discussion and Conclusions: There is a fine balance between the polycationic character of a carrier to its toxicity and transfection efficiency. Magnetofection is a powerful tool to deliver the carrier-siRNA complex to a target cell or tissue.

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Rivera-Rodriguez, Glorimar

Alamo Nole, Luis - Department of Chemistry, Pontifical Catholic University of Puerto Rico-Ponce; Perales Perez, Oscar - Department of Engineering Science and Materials and Department of Chemistry, University of Puerto Rico - Mayaguez; Roman, Felix R. - Department of Engineering Science and Materials and Department of Chemistry, University of Puerto Rico - Mayaguez; Bailon Ruiz, Sonia - Department of Chemistry and Physics, University of Puerto Rico-Ponce

Chemistry

Photodegradation of organic dyes using Quantum Dots of Cd(Se,S) in aqueous solutions

Environmental issues are associated for discharge of industry and municipal waste. The dyes from the textile and paper manufacture can cause serious problems for the toxicity of the compounds themselves and their corresponding byproducts. Quantum dots of Cd(Se,S), a fluorescent material, were used as photocatalytic agent in the degradation of methylene blue (MB) and Victoria blue (VB) under UV irradiation (302 nm) at pH 6.5. The Quantum dots were characterized by Ultraviolet–visible (UV-Vis), X-ray diffraction (XRD) and photoluminescence (PL) techniques. The degradation of MB and VB after the UV irradiation were monitored using High Performance Liquid Chromatography (HPLC) at 600nm. The efficiency of the photodegradation process was dependent on Quantum Dots concentration.

Rodriguez-Alemany, Catalina

Marchany-Rivera, Darya - Chemistry Department, University of Puerto Rico, Mayagüez Campus; Lopez-Garriga, Juan - Chemistry Department, University of Puerto Rico, Mayagüez Campus

Chemistry

CRYSTALLIZATION OF RECOMBINANT HEMOGLOBIN I WITH A HISTIDINE TAG AND ITS MUTANT CONTAINING HISTIDINE E7

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Hemoglobin I (HbI) from Lucina pectinata is a model hemeprotein used to understand H2S interactions with hemeproteins. Recombinant protein hemoglobin I (rHbI) with Gln in the E7 position and a Histidine tag (His-Tag) was prepared in a 5L bioreactor. Kinetically, studies showed similar behavior between HbI and rHbI, therefore, the latter is suitable as the native protein analog. A mutant with Histidine in the position E7 with a His-Tag was obtained to analyze the difference between an H2S protein carrier and an O2 one. Structurally, SAX-WAX data has been obtained, which support that there is no structural differences between these hemeproteins. To ensure this and further explore the internal structural orientation of the amino acids and the effect of His-Tag in the rHbI structure, crystal diffraction patterns are needed. Crystallization of rHbI His-tag and the mutant were conducted by the hanging drop vapor diffusion and counter diffusion techniques at room temperature. Buffers from the Hampton Research Screening Kit 1 and Triana™ Crystallization Kit with pH variations were used as precipitant agents in the screening. The protein sample was prepared at different concentrations with cyanide as a ligand. Crystal formation was observed in buffers containing Lithium Sulfate. The crystals have a reddish-brown color and a circular or rectangular shape with a size range from 9.5?m to 70.0?m, respectively. The seeding technique and further optimization of conditions are being used to enhance crystal quality for X-ray diffraction.

Rodriguez-Benitez, Attabey

Maria del C. Rivera Sanchez - Chemistry, University of Puerto Rico, Rio Piedras Campus; Jose M. Rivera - Chemistry, University of Puerto Rico, Rio Piedras Campus

Chemistry

Synthesis and Self-Assembly Studies of an 8-para-Acethylphenyl-2’-Deoxyguanosine Derivative and its interactions with G-Quadruplex DNA

During the past years, there is an interest in studying the recognition of non-canonical DNA structures known as G-quadruplexes (QDNA), which are abundant throughout our genome and have a great impact on many cellular processes in normal and pathological states (e.g., cancer). The objective of our project is to validate 8-aryl-2'-deoxyguanosine (8ArG) derivatives as a new generation of self-assembled ligands with high selectivity and affinity for the stabilization of QDNA. Our strategy relies on the synthesis of small molecules that can self-assemble into

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precise supramolecular G-quadruplexes (SGQs) and test them as effective ligands for the recognition of different QDNA sequences. Conveniently, the SGQs can interact with a greater surface area and overcome the surface limitation presented in single small molecules, which are the commonly used QDNA ligands. There is also the fact that the sidechains on the SGQs surface may allow the selective surface recognition enhancing its selectivity and affinity between the topology of various DNA structures (e.g., QDNA, dsDNA). We will present our progress in the synthesis and characterization (e.g., 1D/2D HNMR), of the hydrophilic 8-para-acetylphenyl-2’-deoxyguanosine derivative (pAGcat) in addition to studies of its self-assembly and possible interactions with different QDNA structures using dose-response FRET melting assays.

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Rodriguez-Cruz, Michael

Mercado, Joel - Physics-Chemistry, University of Puerto Rico at Arecibo; Cruz, Kevin - Physics-Chemistry, University of Puerto Rico at Arecibo; Serrano, Anumis - Physics-Chemistry, University of Puerto Rico at Arecibo; Colon, Jimary - Physics-Chemistry, University of Puerto Rico at Arecibo

Chemistry

ETHANOL PRODUCTION AND ITS APPLICATION AS FUEL IN A FOUR-CYLINDER CAR

The objective of this investigation was, produce ethanol from molasses of cane and endemic fruits of Puerto Rico by fermentation. The fossils fuels are being depleted and the use of the alternative energies becomes essentially important and indispensable. By this reason we develop this project with the vision of substitute the 10% of the consume of gasoline with ethylic alcohol for light vehicle that works with gasoline. The prime material use for the fermentation was molasses and sugar cane juice. After the fermentation we proceed to the distillation process with a homemade distiller. We would able to make seven fermentations at 30 degree brix average obtaining 27.2L of alcohol at 82.48% volume/volume. All along with the investigation we measure brix, refraction index and density in the fermentation and the distill products. This alcohol was proved in a Datsun 210 from 1982 making some modifications in the carburetor needles and advancing the time of ignition. For the test of combustion of alcohol in the car, we run the car in the facilities of the University of Puerto Rico at Arecibo. The vehicle run satisfactorily, but it required other technic adjustment that we will be doing on the future.

Rodriguez-Diaz, Giovanni

Fajardo, Johanna, M.S. - Chemistry, UPRRP; Cedeño, Julio - Chemistry, UPRRP; Enríquez, Yanira - Chemistry, UPRRP; Montes, Ingrid, Ph.D. - Chemistry, UPRRP; Guadalupe, Ana, Ph.D. - Chemistry, UPRRP

Chemistry

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Synthesis of Ferrocenyl Polymers for Potential Uses in Material Sciences

Ferrocene was discovered in 1951. Since then, its applications that include: biocatalysis, biosensing, materials sciences, biofuel cells, films, anticancer agents, biomedical engineering, electroactive materials, aerospace materials, surface science, biophysics, and biological activity, are an active research area. The main goal of this research is to synthesize and characterize new ferrocene polymers from ferrocenyl chalcones and explore their potential applications. The hypothesis is that ferrocenyl chalcones are potential monomers for ferrocene polymers that could be useful as biosensors and in material sciences due to their electrochemical properties. The general objective is accomplished by the synthesis of a series of ferrocenyl chalcone derivatives that includes the chemioselective reduction of nitro containing precursors, amidation of a phenylamine substrate and its polymerization reaction to obtain homo-, co- and terpolymers. Ferrocenyl chalcone derivatives were obtained with yields that vary from 65% to 86%, while polymers were obtained from 64% to 76%. The characterization of these polymers has been achieved using, IR spectroscopy, UV-Vis, and electrochemistry. The synthetic methodology and characterization of these compounds will be elaborated.

Rodriguez-Negron, Astrid

Cepeda, María de los A. - Department of Science and Technology, Universidad Metropolitana; Román, Natalia I. - Department of Science and Technology, Universidad Metropolitana; Reyes, Cristina M. - Department of Science and Technology, Universidad Metropolitana; Gelpí, Svetlana - Department of Science and Technology, Universidad Metropolitana; Singhal, Rahul - Department of Science and Technology, Universidad Metropolitana; Gómez, Harry - Universidad Interamericana de Bayamón

Chemistry

Crystal Structure Manipulation of ZnO by the Presence of Organic Ligands using the Hydrothermal Method

Zinc oxide (ZnO) is a white inorganic semiconductor that has been proposed for different applications, which include, but do not limit to, medicine, sensors, and solar energy harvesting applications, among others. In our group we have synthesized different ZnO crystal structures by simple wet chemistry synthesis. We

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tested the effect of two different ligands (3 mercaptopropionic acid and benzoic acid) during the synthesis ZnO crystals. Both ligands are mild acids, which compete with the Lewis acid of the reaction, which is Zn2+. The ZnO materials were characterized by different spectroscopic and analytical techniques such as X-Ray Powder Diffraction (XRPD), Scanning Electron Microscope (SEM), Energy Disperse Spectroscopy (EDS), UV vis and IR Spectroscopy. The functionalized materials were also characterized using EXAFS. Preliminary results demonstrate that upon addition of benzoic acid to zinc oxide particles induces the formation of zinc oxide rods. However, the materials functionalized with 3 mercaptopropionic acid have a film-like structure.

Rodriguez-Valdes, Yanira

Prieto, Luis A. - Chemistry Department, University of Puerto Rico - Rio Piedras; Rivera, Jose M. - Chemistry Department, University of Puerto Rico - Rio Piedras

Chemistry

Sugar-Responsive Supramolecular G-Quadruplexes: Initial Studies Towards a Glucose-Responsive System

Stimuli responsive materials have been developed widely in polymer chemistry. Changes in glucose concentration, pH, and temperature are among the external stimuli under which these systems have been tested. Even though the development of stimuli-responsive non-polymeric systems remains a challenge in the field, our group has identified that non-polymeric supramolecular G-quadruplexes (SGQs), based on the self-assembly of 8-aryl-2’-deoxyguanosine derivatives (8ArdGs), can be responsive to stimuli such as changes in pH and temperature. Adding certain boronic acids (BAs) from aryl and heteroaryl aldehydes to 8ArdGs may cause the resulting SGQs to be sugar-responsive. Our aim is to synthesize and study boronic acid-containing guanosine derivatives (BAGs) and their resulting SGQs, but in order to do so we need to choose suitable boronic acid derivatives for the system to be functional at physiological pH. For this, model BA compounds were synthesized via aldol reaction between acetophenone and BA aldehydes and analyzed by NMR spectroscopy (1D/2D); their pKa values were analyzed using UV/Vis spectroscopy. The corresponding aldehydes will be chosen based on the BA model compounds with pKa values close to physiological pH. For example, the reaction between 4-formyl phenyl boronic acid and acetophenone proceeded with 46 % yield and the UV/Vis data correspond to a pKa of 7.4. These results indicate that these compounds can be synthesized with reasonable efficiencies and the aldehyde may

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be used for BAG derivatives. The synthesis of sugar-responsive SGQs might be suitable for biomedical applications such as the development of insulin delivery devices.

Rosado-Gomez, Karolyna

Lizabeth Jimenez - Quimica, UPR-Rio Piedras; Dra. Elsie Orellano; Dr. Nestor Carballeira - Quimica, UPR-Rio Piedras

Chemistry

RT Inhibition Activity of pentacosynoic and pentacosenoic acids

Reverse Transcriptase, RT, is the protein in charge of converting viral ssRNA into proviral dsDNA. This retrotranscription process is of vital importance for the Human immunodeficiency virus, HIV, replication in the host cell. It is for this reason that RT has become a major target in anti-retroviral therapy. There are two types of RT Inhibitors, RTIs: Nucleoside RT Inhibitors, NRTIs, and Nonnucleoside RT Inhibitors, NNRTIs. Our laboratory works on the synthesis of fatty acids as potential biomedical drugs, in this case as RT Inhibitors. For this work, our main goal is to assess the activity of several fatty acids with double or triple bonds at different positions along a 25-carbon chain against the HIV-RT and to compare the experimental agents with the positive control 3-Azido-3-deoxythymidine, AZT control. We performed a non-radioactive colorimetric assay to measure the activity of HIV-RT with our fatty acids as possible HIV-RT Inhibitors. The RT Assay uses the quantity of synthetized DNA as parameter to measure HIV-RT activity. This is possible to measure thanks to the digoxigenin and biotin labeled nucleotides from the assay that bind to the newly synthetized DNA molecule by HIV-RT. A peroxidase substrate binds to the digoxigenin labeled DNA to produce a colored product. Measurement of absorbance is directly correlated to HIV-RT activity and our results were expressed with the IC50 value. Our results showed ?5- pentacosynoic acid, IC50 = 24 ± 1 ?M, and ?5- pentacosenoic acid, IC50 = 38 ± 1 ?M, as potential drugs for the inhibition of HIV-RT.

Saldana-Mendez, Andrea

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Rivera, Nilka - Chemistry, UPR-Mayaguez

Chemistry

STUDY OF MEDICINAL PROPERTIES OF CNIDOSCULUS CHAYAMANSA

Cancer is the term used to describe diseases in which abnormal cells divide without control and invade other tissues. Natural products, like plant extracts, are important sources of anti-cancer (lead or hit) molecules. A strong correlation between the phenolic content in the plant extracts and their anticancer activities have been identified. The beneficial effects derived from phenolic compounds have been attributed to their antioxidant activity. Based on this correlation, this research focuses on the determination of the Total Phenolic Content in the plant Cnidoscolus chayamansa (also known as Chaya), the determination of its antioxidant properties, anticancer activity against the colon cancer cell line (HT-29), and bioactivity assay using brine shrimps. Extractions of the leaves of Chaya have been performed using different solvents with a variety of polarities. We determined the total phenolic content of each extract using the Folin-Ciocalteu reagent and the antioxidant properties using the di(phenyl)-(2,4,6-trinitrophenyl)iminoazanium (DPPH) assay. Extracts were incubated with colon cancer cells (HT-29) in order to measure the cytotoxic effects towards the cell line. The bioactivity of the plant extracts was evaluated using the shrimp lethality assay. An analysis of the total phenolic content, bioactivity, the antioxidant and cytotoxic properties against colon cancer cells of the fractions isolated will be presented.

Santaliz-Casiano, Ashlie

Nilka Rivera Portalatin - Chemistry Department, University of Puerto Rico, Mayagüez; José Robles - Chemistry Department, University of Puerto Rico, Mayagüez

Chemistry

Evaluation of antioxidant and anti-cancer properties of Annona muricata.

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Annona muricata, also known as soursop, has been used as a medicinal treatment for various diseases including cancer. Studies inform the presence of cytotoxic acetogenines in the leaves of Annona muricata. The present study was undertaken to investigate the antioxidant properties and possible anticancer effect of Annona muricata's fruit. A series of solid-liquid extractions were performed with solvents of different polarities. Various chromatography techniques were used to separate the soursop extracts and obtain the different compounds to consider. The antioxidant capacity of A. muricata was measured using the DPPH assay. The inhibitory effect of compounds extracted from Annona muricata on the proliferation of cancer cell was predicted by using the brine shrimp lethality test, which has shown to have a strong correlation with anti-cancer compounds. The antioxidant capacity and the bioactivity obtained in the brine shrimps lethality assay will be presented. In the future, the cytotoxicity of the most active fractions will be tested against colon cancer cells in an effort to find a safer, more accessible treatment for this terrible disease.

Santiago-Maldonado, Xaimara

García, Derek - Department of Chemistry, University of Puerto Rico-Río Piedras Campus; Casellas, Jean C. - Department of Biology, University of Puerto Rico-Río Piedras Campus; Hernández, Anibal A. - Department of Chemistry, University of Puerto Rico-Río Piedras Campus; Diaz, Liz M. - Department of Chemistry, University of Puerto Rico-Río Piedras Campus; Roberson, Loretta - Department of Environmental Sciences, University of Puerto Rico-Río Piedras Campus

Chemistry

Determination of Organic Volatile Compounds of the Red Macroalgae Glacilaria Tikvahiae Cultivated Under Different Conditions Using Headspace-Solid Phase Microextraction and Gas Chromatography-Mass Spectrometry

It has been proposed that the production of volatile organic compounds (VOCs) by macroalgae is a metabolic response towards the changes its environment undergoes, as a mechanism of defense, and others. If such production can be effectively quantified, it would be a potential method that would serve as an indicator of particular changes in the environment. Analytical techniques such as headspace-solid phase microextraction (HS-SPME) coupled with gas chromatography-mass spectrometry (GC-MS) were used to determine the VOC profiles of the red macroalgae Gracilaria tikvahiae cultivated under different

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environmental conditions, i.e. illumination vs. lack of illumination, as well as high salinity vs. low salinity. The most abundant families of VOCs that were useful for the comparison of the response of the macroalgae to different conditions include aldehydes, sulfides, ketones, and others. Overall, the production of VOCs was greater in algae cultivated with illumination compared to those cultivated in absence of light. This may possibly indicate that such compounds are a source that comes from both metabolic and photosynthetic processes. Salinity also played an important role in the production of volatile organic compounds. As the percent of salinity increases the number of VOC's decrease. This may illustrate a possible homeostatic response towards a threatening environment with respect to their stored nutrients, osmoregulation.

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Santiago-Martoral, Liz

Feliciano, Melivette - Chemistry, UPR-RIO PIEDRAS; Gomez, Valerie - Chemistry, UPR-RIO PIEDRAS; González-Robles, Tania - UPR-RIO PIEDRAS

Chemistry

Synthesis and characterization of nanocellulose-based composites for applications in forward osmosis

Cellulose nanocrystal (CNC) is a revolutionary bionanopolymer that offers promising mechanical and chemical properties to further advance the field of nanotechnology. In this work, we are exploring the feasibility of synthesizing microbiological resistant CNC-based composites for the development of forward osmosis membranes that can be later employed for water purification purposes. Cellulose nanocrystals were chemically modified, through a sililation reaction of the exposed CNC-hydroxyl groups. These constructs were then modified with silver (Ag) and platinum (Pt) nanoparticles to obtain two plausible coatings with antimicrobial properties. Both CNC-based composites constructs were characterized and analytically compared by Dynamic Light Scattering (DLS), Thermo Gravimetric Analysis (TGA), Raman Spectroscopy (RS) and Scanning Electron Microscope (SEM). In future work, the microbial resistance investigation of these two candidates would uncover the best antimicrobial CNC-based composite most suitable for water purification technologies.

Santiago-Rosario, Raiza

Lopez, Genesis - Chemistry, UPR-Humacao; Ortiz, Selina - Chemistry, UPR-Humacao; Espinosa, Sandraliz - Chemistry, UPR-Humacao; Rosario, Maricelys - Chemistry, UPR-Humacao; Padilla, Miriam - Chemistry, UPR-Humacao; Gonzalez, Veronica - Chemistry, UPR-Humacao

Chemistry

Synthesis of 1-Benzazepines as Nicotinic Acetylcholine Agonists

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The continuous and rapid increase of multiple cases of neurodegenerative diseases with limited effective treatments has motivated us in the development of new drugs that can work as nicotinic acetylcholine agonists. Cyclic amino derivatives, such as 1-benzazepines, have been recently studied as relevant structures in biologically active compounds and presently have gain interest in for the treatment of neurodegenerative diseases, such as Alzheimer’s and Parkinson. In our laboratory, we are interested in investigating convenient methods for the synthesis of new analogues of Galantamine, to use them as allosteric nicotinic receptors agonists. Previously, our laboratory developed an efficient method for the synthesis of 1-benzazepines by the reductive rearrangement of O-tert-butyldimethylsilyl oximes using boron triflouride and borane in THF under reflux conditions. Now, we have synthesized 7-methoxy-2,4,5-tetrahydro-1-benzazepine and 7,8-dimethoxy-2,4,5-tetrahydro-1-benzazepine and prepared new benzazepine analogues with different substituents at the nitrogen atom to further study their neurobiological an toxicological properties.

Sierra-Torres, Lourdes

Torres Domínguez, Lisnell M. - Physics/Chemistry, UPR-Arecibo; Martínez Caballero, Carolyn - Physics/Chemistry, UPR-Arecibo; Mejías Rivera, Kiara - Physics/Chemistry, UPR-Arecibo

Chemistry

Producción de Biodiesel a partir de Aceite Vegetal Nuevo y Usado

El proposito de esta investigacion es demostrar que se puede producir biodiesel a partir de aceite vegetal nuevo y usado, como fuente de energia alterna sin depender del combustible fosil. Para preparar el biodiesel en un reactor, se agito el aceite y la mezcla de metoxido de sodio por un periodo de 50 minutos, manteniendo con un controlador la temperatura a 48 °C. Luego, esta mezcla se paso a un embudo de separacion y por decantacion se separo la fase organica de la fase acuosa. Como producto principal se obtuvo el biodiesel y como residuo la glicerina. El biodiesel se sometio a unas etapas de lavado con agua destilada para eliminar cualquier impureza. El rendimiento promedio de produccion para el aceite nuevo fue de un 83%, mientras que para el aceite usado fue de 80%. La viscosidad promedio para el biodiesel a partir de aceite vegetal fue de 6.12 g/cm-s, lo cual indica que se encuentra dentro del rango del biodiesel industrial. Este biodiesel fue probado en diferentes vehiculos de motor diesel, camioneta Ford 150, tractor y una

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excavadora propiedad de la Universidad de Puerto Rico Recinto de Arecibo, el cual tuvo un desempeno optimo.

Strubbe-Rivera, Jasiel O.

Velez-Burgos, Yaritza - Department of Chemistry, Pontifical Catholic University of Puerto Rico; Martinez-Torres, Natalia - Department of Biology, Pontifical Catholic University of Puerto Rico; Rodriguez-Quinones, Jose F. - Department of Chemistry, Pontifical Catholic University of Puerto Rico

Chemistry

Effect of Copper Deficiency in the Cell Viability of the Budding Yeast Saccharomyces cerevisiae

Copper transport inside of the cell is very important since this transition metal catalyzes many reactions required for proper cellular functions. Copper transport in the yeast Saccharomyces cerevisiae, is regulated by proteins located in the plasma membrane known as copper transporters. Ctr1p regulates the high affinity transport machinery and serves as a major copper transporter to the intracellular compartment. Once the copper is inside the cell, it is sorted to a specific organelle by one of the three independent copper chaperones -Atx1p, Cox17p, and Ccs1p-. In this study, chemical and genetic approaches are used to mimic copper deficiency conditions in yeast cells. The chemical and genetic involves the use of bathocuproine sulfonate -BCS-, a chelating agent that prevents copper to serve as a co-factor in many enzymatic reactions. The genetic approach is achieved by deleting the CTR1 gene in yeast cells -ctr1 mutant cells-. We observed that cell viability is decreased in wild type cells treated with moderate concentrations of BCS -100-400 micromolar-. On the other hand, ctr1 mutant cells presented a defect in cell growth. These preliminary results indicate that both chemical and genetics approaches can be used to examine copper-dependent phenotypes in yeast. Currently, we are identifying other yeast genes involved in copper transport that may be associated with health conditions in humans. This research is supported by an Institutional Development Award -IdeA- from the National Institute of General Medical Sciences of the National Institutes of Health under grant number P20 GM103475.

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Toro-Cruz, Glory A.

Rivera Betancourt, Harry - Taveras Gomez, Jancel

Chemistry

Preparation and Characterization of Palladium Catalyst for Fuel Cell Application

Palladium catalysts have attracted a great deal of attention due to their promising applications, particularly as the electrode catalyst for low-temperature fuel cells. The goal of this work is to synthesized palladium catalysts by using a simple and economical co-precipitation method. Palladium (Pd) catalyst were synthetized by reduction method using NaBH4. Characterization of synthesized catalyst will be presented.

Torres-Maymi, Bianca

Casañas, Barbara - Chemistry, UPR Rio Piedras; Enríquez, Yanira - Chemistry, UPR Rio Piedras; Montes, Ingrid - Chemistry, UPR Rio Piedras; Guadalupe, Ana R. - Chemistry, UPR Rio Piedras; Colón, Jorge L - Chemistry, UPR Rio Piedras

Chemistry

Chemical characterization of ferrocene derivatives and their intercalation into zirconium phosphate layers for potential use as redox mediators in biosensors

Ferrocene Fe(C5H5)2 is an organometallic compound that has two cyclopentadienyl rings bound on opposite sides of a central iron atom and that has been used as an electron mediator in amperometric sensors. This application has encouraged the synthesis and electrochemical characterization of many ferrocene derivatives. Zirconium bis(monohydrogen orthophosphate) monohydrate (Zr(HPO4)2.H2O, ?-ZrP) best known as zirconium phosphate (ZrP) is an inorganic layered nanomaterial. The highly hydrated phase of ZrP known as the ?-phase, is an acidic ion exchanger with an interlaminar distance of 10.3 Å that has been used for the immobilization of several photo-, bio- and redox compounds. Three

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ferrocenyl chalcones derivatives (H, 3,4-Cl and 4-Cl) have been intercalated in the ZrP layers. The intercalations of the ferrocene derivatives where optimized in order to understand the interaction with the ZrP layers. The optimization consists of adjusting the amount of the ferrocene derivatives in the intercalation reaction to optimize the loading percent inside the layers of ZrP and we started characterizing the products using X-ray powder diffraction (XRPD). XRPD data indicates that new intercalated phases with expanded interlayer distances of ~9.8 Å were obtained. In addition, UV-vis spectrophotometricy characterization results for the three derivatives were: 4-Cl derivative (?max = 269 nm, ? = 59211 M-1cm-1), H derivative (?max = 266 nm, ? = 79146 M-1cm-1), and 3,4-Cl derivative (?max = 267 nm, ? = 63935 M-1cm-1). We are currently working on improving the reproducibility of the intercalation reactions and the chemical and electrochemical characterization of these intercalated compounds.

Torres-Teissonniere, Carlos F.

Collazo Acevedo, Glorimaris - Chemical Engineering, University of Puerto Rico-Mayaguez Campus; De Jesús Echevarría, Maritza* - Chemistry, University of Puerto Rico-Mayaguez Campus

Chemistry

HEALTH IMPACT OF TOTAL SUSPENDED PARTICLES (TSP) AND CHRONIC OBSTRUCTIVE PULMONARY DISEASES (COPD) CORRELATION IN MAYAGUEZ CITY

The major environmental health issue for people living in metropolitan areas is the air pollution. This health issue arises as a consequence of urban development and also with the atmospheric activities of the Sahara dust and Soufrière Hills volcano in the Caribbean. A research study of the air pollution impact in the municipality of Mayagüez was established to evaluate the correlation of total suspended particles, TSP/PM10 and the chronic obstructive pulmonary diseases, COPD. A high volume sampler, HVS system was used to test the daily TSP values. The filter is exposed for 24 hours in the HVS from August to November 2013 using the gravimetric method. The COPD data was provided by the ASES “Administración de Seguro de Salud de Puerto Rico”. The arithmetic mean TSP results for the four months were 25.47 µg/m3. The highest value was 67.22 µg/m3 in the month of September and the lowest value was 7.45 µg/m3 also in the same month. The Mayagüez COPD hospitalization range was between 38 and 67. In the month of August there is a proportionally direct correlation between the TSP and COPD hospitalizations. The

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preliminary results show that there is a predisposition when the TSP value increase the number of hospitalizations related to respiratory diseases also increases.

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Vargas-Perez, Brenda

Rodriguez, Angel - Biotechnology, UPR-Mayaguez; Simpson, Jessica - Biology, UPR-Mayaguez

Chemistry

Cadmium Phytoremediation of In Vitro Culture with Micro-propagated clones of Spermacoce Assurgens

Spermacoce assurgens, known by the vernacular name of “Juana la Blanca”, has been selected as a target plant for the phytoremediation of Cd+2. Juana la Blanca is a medicinal plant native to Puerto Rico used mostly to disintegrate kidney stones. Phytochemistry of this plant suggests strongly that Juana can also be a potent phytoremediator. Preliminary work in our lab with Juana la Blanca as phytoremediator for the explosive TNT (trinitrotoluene) gave encouraging results. These bright preliminary results were shadowed by the suspicion of fungal contamination. To clarify this situation and ascertain the putative strong phytoremedition role of Juana la Blanca, we decided to isolate and identify the organism growing in symbiosis with this plant. The first objective of the research was to obtain a line of plant clones for experimentation using the technique of in vitro plant cell and tissue culture. Special attention was placed in detection of the focus of contamination, the identification of the organism and its eradication. It has being found that bacterial contamination of the genus Xanthomonas was the culprit of the contamination. Following multiple trials using proper aseptic techniques and controlled environmental conditions, clones of the available mother plant were successfully grown free of contamination. The second objective was to expose plants to Cd+2. Plant clones were re-cultured in vitro in media doped with Cd+2. A control group of clones was set aside to establish a basis for comparison. Plants were tested for Cd+2 resistance. We have found that Juana survive in media up to 50 ppm Cd+2. The third objective was to quantify Cd+2 in culture media. It is assumed that the quantity of cadmium ions missing from the medium has sequestered by the plants. A modified procedure of Hach Colorimetric Dithizone Method was used. Juana proved to be an excellent phytoremediator, accumulating 60% of the Cd+2 added.

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Vazquez-Delgado, Maycor

Maycor L. Vazquez Delgado - Science and Technology, Turabo University; Fransisco Marquez - Science and Technology, Turabo University; Maria Cotto - Scince and Technology, Turabo University

Chemistry

Synthesis and Photocatalytic Activity of Titanium Oxide Nanowire

Water pollution has emerged as a primary concern in environmental issues due to the production and consumption of pharmaceuticals and personal care products (PPCP’s). The PPCP’s include among others, lotion, cosmetics and sunscreen products and are chemical substances resilient to traditional remediation techniques such as biodegradation. Advanced oxidation processes (AOP’s) have been developed as a promising decontamination method due to its capability to generate radical species, being a non-selective reaction and with applications not only in liquid, but also in gaseous phase. AOPs processes can lead to complete mineralization of organic pollutants. The use of photocatalytic materials is a common AOPs technique but the use of the photocatalytic nanowires could be a new option for the degradation of the contaminants. In this regard, titanium oxide nanowires (TiO2NWs), as rutile phase, have been synthesized by hydrothermal method. The synthesized nanowires have been characterized using scanning electron microscopy (SEM), X-ray diffraction (XRD), and area BET and will be tested in the degradation process of different environmental pollutants.

Vazquez-Salgado, Alexandra

Tinoco, Arthur D. - Chemistry Dept., UPR- Rio Piedras Campus; Loza-Rosas, Sergio A. - Chemistry Dept., UPR- Rio Piedras Campus

Chemistry

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Synthesis, structural characterization and evaluation of cytotoxic effects of the Ti(IV)-Deferasirox complex in A549 lung cancer cells and MRC5 healthy lung cells

Titanium based complexes have been promising anti-cancer drugs since 1979, but their hydrolytic instability in physiological conditions has made it difficult to achieve this. Even though transferrin, Tf, the Fe3+ transport protein, accomplishes Ti4+ stability in its binding site and carries out the transportation function, the cytotoxicological activity of the Ti4+ in cancer cells didn’t achieve a significant effect. In this context, it is necessary to find ligands that could act as a Tf biomimetic, a molecule that imitates the binding site and that offers the same stabilizing and transporting function. The proposed pharmacological design supposes the intracellular metal exchange: once Ti4+ has been released, the ligands should act as iron chelators and extract Fe3+, essential for the survival of the cancer cell. As part of this project, synthesis of potential Ti4+ small molecule anticancer drug and spectroscopic studies were analyzed to see their bioactive form and stability in solution. Crystals of the complex were obtained to produce solid state structures of the compounds, so this crystal structure analysis is combined with solution state spectroscopic work, IR spectroscopy, 13C and 1H NMR, elemental analyses, to understand the stability of the complexes in solid state and solution.

Vega-Alicea, Deborah

Vega Alicea,Doris - Chemistry,PUCPR; Batista Parra, Adalgisa - Chemistry, PUCPR

Chemistry

Catechol’s analogs

Catechols are polyphenolic compound as are quercetin and catechin, which have properties such as antioxidants, anti-inflammatory and neuro-protector. Hydroquinone is a compound used in products to treat skin blemishes; also it is used for photographic developer, and in paints. Hydroquinone as a chemical property can oxidize when this happens the molecule loses 2 protons and transferred 2 electrons. For the present study it was synthesized a few catechol’s analogs with a chain of different length at the position two of the aromatic ring with the purpose of study their electrochemical behavior and biological function. The

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separation, purification and characterization were done by the following techniques: column chromatography, TLC, rotaevaporation and NMR. The following intermedia were prepared: 2-5- bromopentyl-4-dimethoxybenzene, 2-6-bromohexyl-4-dimethoxybenzene and 2-9- bromononyl-4-dimethoxybenzene which were also submitted to NMR spectroscopy for characterization before proceeding with the next steps of the synthetic pathway.

Vega-Alicea, Doris

Vega Alicea,Deborah - Chemistry,PUCPR; Batista Parra, Adalgisa

Chemistry

Catechol’s analogs

Catechols are polyphenolic compound as are quercetin and catechin, which have properties such as antioxidants, anti-inflammatory and neuro-protector. Hydroquinone is a compound used in products to treat skin blemishes; also it is used for photographic developer, and in paints. Hydroquinone as a chemical property can oxidize when this happens the molecule loses 2 protons and transferred 2 electrons. For the present study it was synthesized a few catechol’s analogs with a chain of different length at the position two of the aromatic ring with the purpose of study their electrochemical behavior and biological function. The separation, purification and characterization were done by the following techniques: column chromatography, TLC, rotaevaporation and NMR. The following intermedia were prepared: 2-5- bromopentyl-4-dimethoxybenzene, 2-6-bromohexyl-4-dimethoxybenzene and 2-9- bromononyl-4-dimethoxybenzene which were also submitted to NMR spectroscopy for characterization before proceeding with the next steps of the synthetic pathway.

Velazquez-Nieves, Glory

Fernandez, Victor - Chemistry, University of Puerto Rico, Mayaguez; Perales, Oscar - Chemistry, University of Puerto Rico, Mayaguez; Roman, Felix - Chemistry, University of Puerto Rico, Mayaguez

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Chemistry

DETERMINATION OF MAGNETITE NANOPARTICLES REMOVAL EFFICIENCY OF 17?-ETHINYLESTRADIOL FROM WATER SYSTEMS

The synthetic hormone 17?-ethinylestradiol (EE2) is a potent estrogen receptor agonist that’s used as the main component of birth control pills and other related drugs. Due to its frequent use discharge from pharmaceutical industries into waste streams had shown an alarming increase of EE2 concentration. Conventional water treatment plants con not remove EE2 and exposure it’s to wildlife can cause several adverse effects to their health and anatomic development including the feminization of male fish. The following study is aimed to determinate the applications of nanoparticles such as magnetite functionalized with sodium oleate as adsorbent for the removal of EE2. Preliminary results showed removal efficiency between 25-30% of EE2 in aqueous solutions at concentrations as high as 30 ppm of EE2 and 0.5 g/L of the oleate functionalized nanoparticles when using the HPLC. The method developed for this experiment can be optimized with potential to be used to remove this harmful synthetic hormone from drinking and waste waters.

Velez-Afanador, Melbaliz

Franqui, Naymar - Biology, UPR-Arecibo; Cuba, Amarilys - Physics-Chemistry, UPR-Arecibo; Alvarez, Selimar - Physics-Chemistry, UPR-Arecibo

Chemistry

Bacterial Inhibition with Algae Extract of Padina gymnospora

Recognizing the actual situation of antibiotic resistance, we were trying to find an alternative to this difficulty. For this reason, we decided to prove if the brown algae, Padina gymnospora, has an in-hibitory effect over bacterium. The algal samples were collected over reef zones of La Parguera in Lajas Puerto Rico. These were settled to the lab with sea water and ice. Then, we proceed to washed it with fresh water to remove any salt or other particles before the extraction. To complete the extraction process was necessary the use of organic solvents such as chloroform and methanol in a 2:1 proportion. During the procedure of rotary evaporation, the

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solvents were separated of the liposoluble extracts from Padina. To test and compare the antibacterial activity of the extract, was required the use of commercial antibiotics. This was executed using the disk diffusion assay. The bacterial stock was classified as Gram (+) or Gram (-). The latter one was consisted of Escherichia coli and Pseudomona aeruginosa. In change, in the Gram (+) group were Staphylococcus aureus and Bacillus cereus. The results demonstrated that the inhibition varies according the type of bacteria used. Thus, the data of the standard deviation have shown that the inhibitory zone diameter cor-responding to the algal extract have been way more effective compared to a commercial antibiotic like penicillin. For instance, Pseudomonas aeruginosa had a deviation of 14.8 ± 1.76 mm in com-parison to penicillin which had a deviation of 2 ± 5.06 mm. Moreover, there is a seasonal influence in Padina gymnospora, from which we concluded that the inhibitory activity is related with the algal reproductory cycle.

Vera-Rosado, Adelfa

Casañas, Bárbara - Chemistry, University of Puerto Rico Rio Piedras; Aponte, Juan Carlos - Chemistry, University of Puerto Rico Rio Piedras; Montes, Ingrid - Chemistry, University of Puerto Rico Rio Piedras; Colón, Jorge - Chemistry, University of Puerto Rico Rio Piedras

Chemistry

Intercalation and Characterization of Ferrocene Derivatives in Zirconium Phosphate Layers by Direct Ion Exchange

The study and research of the biomedical applications of nanotechnology has been up and rising during the last decade. One active field of investigation is the use of nanoparticles as an alternative, targeted drug delivery system, particularly for the delivery of chemotherapeutic drugs for cancer treatment. Zirconium phosphate (ZrP) is a layered inorganic nanomaterial which has been proven to intercalate organometallic compounds. In its alpha phase (?-ZrP), it is monohydrate (Zr(HPO4)2•H2O) with an interlaminar distance of 7.6 Å. However, in its hydrated theta phase (Zr(HPO4)2•6H2O, ?-ZrP), the interlaminar distance expands to 10.3 Å, and has been previously reported in our laboratory for its use in drug carrier applications. The long-term goal of the laboratory is to develop new controlled drug carriers using ZrP. Ferrocene and ferrocene derivatives are redox-active compounds that have been used as electron mediators in amperometric sensors, and are examples of organometallic compounds that have been intercalated in zirconium phosphate. The ferrocenyl chalcone, Fc-NH2, which has been proven to

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have antiplasmodial activity, and the ferrocenyl chalcone analogue, ferrocene-indanone, which has shown cytotoxicity activity against cancer cells in previous studies, have been intercalated successfully into ?-ZrP at different ratios. Characterization of the intercalation products of using X-ray powder diffraction (XRPD) showed expanded interlayer distances, of 9.70 Å for Fc-NH2 and 9.96 Å for Fc-indanone. The characterization of the Fc-NH2 and the ferrocene-indanone intercalation product, using cyclic voltammetry (CV), Fourier Transform-Infrared spectroscopy (FT-IR), electronic spectroscopy (UV-vis), and energy dispersive X-ray spectroscopy (EDS) by means of scanning electron microscopy (SEM) will be presented as well.

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Computer Science

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Albertorio-Rodriguez, Luis

Computer Sciences

Mobile Malware Intrusion Detction by Deception using the Sensibility Testbed} \author{

New technologies make smartphones more sensitive to the environment around them and this in turns make malicious apps a greater threat. Malware can steal the information from your smartphone and even from other input devices around ,using its sensors. In this work we present a method to identify the presence of Malware and to protect information in Android using decoys.

Castro-Soto, Emmanuel

Damudt, Daniel - Computer Science, UPR Arecibo; Santiago, Samuel - Computer Science, UPR Arecibo

Computer Sciences

Official Map And Associations Android Application For The University Of Puerto Rico Arecibo Precinct

As smartphones continue to evolve, we constantly find new ways to leverage their capabilities for the benefit of the worldwide community. In the case of this research project, it sought out to create a mobile application for the Android operating system that would be of benefit to the university's fellow students. The main purpose of the application would be to provide the students and faculty of the precinct with concise and accurate university information in a convenient and easy to use application form. Before beginning development of the application, extensive research was conducted in order to determine what the university's community desired as main features, on how these features would be designed and developed and what equipment would be needed to do so. Using the information of this research, the team decided the application would consist of two main components. These components are a map of the precinct's key locations and a university associations

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database. The application research and development team was then split into two sub-teams, one for each main section. These sub-teams dedicated the first semester of this three semester research project to develop the core foundations of each section and brought the application to a near beta stage. The application was then presented to the university's community so feedback would be received from their work. The entirety of the research and development team would like to present its advancements in the mobile application field to the research community.

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Coll-Varela, Frankie

Nieves, Delma - Computer Science; Rodriguez, Ana - Computer Science; Rosario, Angelica - Computer Science; Coll, Frankie - Computer Science

Computer Sciences

Mobile Application Development for UPRA students

“Pregunta Lobo” is an Android application developed to serve as a tool for the University of Puerto Rico in Arecibo (UPRA) students and community. Made by UPRA students for UPRA students, “Pregunta Lobo” is an innovative application that will help students throughout their university years as an offline, always-available personal assistant on UPRA topics. The application contains a variety of information about the UPRA, including answers to student frequently asked questions such as important dates, the academic calendar, academic departments’ vision and mission, locations of interest in campus, student organizations, internship and exchange opportunities, in-campus security, and many other topics of everyday college life that were acquired through student and university personnel surveys. Users can obtain the answers via a natural language interface, which is very simple and user friendly. The app also contains a feedback mechanism to gather the statistics of usage and obtain additional questions from users. A functional prototype was tested within the UPRA community and obtained positive reviews. The application continues its testing process and is on track for a beta release later this year.

Damudt-Galera, Daniel

Castro, Emmanuel - Computer Science, UPR-Arecibo; Santiago, Samuel - Computer Science, UPR-Arecibo

Computer Sciences


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As smartphones continue to evolve, we constantly find new ways to leverage their capabilities for the benefit of the worldwide community. In the case of this research project, it sought out to create a mobile application for the Android operating system that would be of benefit to the university's fellow students. The main purpose of the application would be to provide the students and faculty of the precinct with concise and accurate university information in a convenient and easy to use application form. Before beginning development of the application, extensive research was conducted in order to determine what the university's community desired as main features, on how these features would be designed and developed and what equipment would be needed to do so. Using the information of this research, the team decided the application would consist of two main components. These components are a map of the precinct's key locations and a university associations database. The application research and development team was then split into two sub-teams, one for each main section. These sub-teams dedicated the first semester of this three semester research project to develop the core foundations of each section and brought the application to a near beta stage. The application was then presented to the university's community so feedback would be received from their work. The entirety of the research and development team would like to present its advancements in the mobile application field to the research community.

Deliz-Burgos, Giovanni R.

Lamboy, Swanny - Department of Biology, University of Puerto Rico at Humacao; Esteban, Ernesto - Department of Physics, University of Puerto Rico at Humacao

Computer Sciences

A New PSA Test Interpretation For Prostate Cancer

Prostate cancer is the second and first type of cancer with major incidences and mortality rates in the USA, and Puerto Rico, respectively. Since 1986, a biomarker called Prostate-Specific Antigen (PSA) is used worldwide to screen prostate cancer, and other prostatic diseases such as benign prostatic hyperplasia (BPH). However, PSA tests are unfortunately ambiguous and may lead to under or over-treatments. To improve the prognosis and diagnosis of prostatic diseases, we have developed a quantitative approach that is an extension of the Swanson et al seminal paper. Our procedure can be used to study PSA dynamics in patients with Benign Prostatic hyperplasia (BPH), prostate cancer, and those with BPH and prostate cancer.

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Lotti-Diaz, Leilani

García Herrera, Yaileen - Ciencias Naturales, Universidad Sagrado Corazón; Salgado Rodríguez, Alexander - Ciencias Naturales, Universidad Sagrado Corazón; Guzmán Blas, Rolando - Ciencias Naturales, Universidad Sagrado Corazón; Olmo Soto, John - Ciencias Naturales, Universidad Sagrado Corazón

Computer Sciences

Empirical Model of Polymer Electrolyte Membrane Fuel Cells (PEMFC) using Scilab

The technology of fuel cells has received much attention in recent years due to its high efficiency and low emissions. There are different types of fuel cells, in our case we will focus on the Polymer Exchange Membrane Fuel Cell (PEMFC). Hydrogen or alcohol can be used in these cells as fuel for the anode and air or oxygen for the cathode. Simulations and models are helpful for developers of fuel cells because it can help improve the design of fuel cells as well as reduce costs, optimize and make them more efficient. A good model should predict the performance of fuel cells in a wide range of operating conditions. Some important parameters to include in a fuel cell model are the cell temperature, fuel temperature, temperature of the oxidant, the pressure of fuel or oxidant, voltage and electric current of the cell, and the fraction weight of each reagent. It is possible to develop models and simulations using Scilab program. The fuel cell models obtained will be used to fit the experimental data and use it as an analytical tool that describes the characteristics of voltage vs. electricity in a fuel cell.

Maisonet-Guzman, Hector

Computer Sciences

EXTENDING SalHUD TO PROCESS DATA ON THE INCIDENCE OF DENGUE FEVER IN PUERTO RICO

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The research consists of expanding the SalHUD (measure and display different type of disease) tool to include the dengue fever data which publish on the Puerto Rico’s Department of Health (PRDOH) website. It also includes a manometer-type (gauge) tool that classifies the different levels as safety, warning or danger zone, in the incidence of the selected municipality. However, SalHUD uses information from the Statistical Office of Puerto Rico website in order to become a dynamic tool that can produce visuals (through the Atlas PR tool) and organize the data under selected time frames such as years. Furthermore, a histogram-type graphic is added to illustrate the data. To evaluate the incidence of dengue in the Island, we resolve to use a gauge. The information on the gauge is the municipality and the percentage of dengue cases in relation to the total number of residents in the municipality. In addition, it includes a histogram that shows the incidence rate by region, as defined by the PRDOH, and display the incidence rate of dengue of total cases among the population in the selected region. This investigation includes the incidence of the dengue as part of its data set provides and a visualization tool by painting the map of Puerto Rico dynamically. The results from this investigation can be used to help the corresponding Authorities in the decision making process of assigning the economic and human resources needed in an epidemic situation, by highlighting the municipalities that need to prioritize during the intervention stage.

Melendez-Rios, Gustavo

Melendez Rios, Rafael - UPR-RIO PIEDRAS

Computer Sciences

On the Cross-Correlation of Families of 3D Welch Costas Arrays

Costas arrays are sequences of dots in an n x n grid with one dot per column and one dot per row. An example of Costas arrays are those obtained by the Welch construction. The Welch construction was recently extended to multiple dimensions, for instance, the 3D Welch Costas arrays are sequences of p^2 – 1 planes with dimensions p x p with p^2 – 1 dots where p is a prime number. Each plane has one dot and the coordinates (within the plane) of each dot are distinct. The cross-correlation of two Costas arrays is the maximum number of dots that can coincide when one array is placed on top of the other and is shifted in all possible ways. In previous work our group presented the shear symmetry to produce more multidimensional Costas arrays by rearranging the planes in a Welch Costas array. In this talk, we present an upper bound for the cross-correlation between any two Costas arrays in a family formed by a 3D Welch Costas arrays and all of its column

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shears. A similar result is obtained for the family of a 3D Welch Costas and its row shears and for a family of a 3D Welch Costas arrays and a composition of both of its shears. This type of arrays with good cross-correlations properties are important for applications to digital watermarking and optical orthogonal codes.

Nieves-Rivera, Delma

Nieves Rivera, Delma - Computer Science, UPR-Arecibo; Coll Varela, Frankie - Computer Science, UPR-Arecibo; Rodriguez Medina, Ana - Computer Science, UPR-Arecibo; Rosario Maisonet, Angélica - Computer Science, UPR-Arecibo

Computer Sciences



Rodriguez-Medina, Ana Cristina

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Nieves Delma - Computer Science, UPRA; Rodriguez Medina Ana - Computer Science, UPRA; Coll Frankie - Computer Science, UPRA; Rosario Angelica - Computer Science, UPRA

Computer Sciences



Rosario-Maisonet, Angelica

Nieves Rivera, Delma - Computer Science; Coll Valera, Frankie - Computer Science; Rodriguez Medina, Ana - Computer Science

Computer Sciences

Pregunta Lobo

“Pregunta Lobo” is an Android application developed to serve as a tool for the University of Puerto Rico in Arecibo (UPRA) students and community. Made by UPRA students for UPRA students, “Pregunta Lobo” is an innovative application that will help students throughout their university years as an offline, always-

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available personal assistant on UPRA topics. The application contains a variety of information about the UPRA, including answers to student frequently asked questions such as important dates, the academic calendar, academic departments’ vision and mission, locations of interest in campus, student organizations, internship and exchange opportunities, in-campus security, and many other topics of everyday college life that were acquired through student and university personnel surveys. Users can obtain the answers via a natural language interface, which is very simple and user friendly. The app also contains a feedback mechanism to gather the statistics of usage and obtain additional questions from users. A functional prototype was tested within the UPRA community and obtained positive reviews. The application continues its testing process and is on track for a beta release later this year.

Ruscalleda-Escobar, Emmanuel

Megret, Remi - Department of Mathematical Sciences, University of Puerto Rico - Mayaguez

Computer Sciences

Algorithms for the Analysis of the Spatial Properties of Near-Infrared Chemical Images

By new FDA initiative on process analytical technology, the pharmaceutical manufacturing industries have to start considering the effect of components physical properties on their solid medications such as tablets or film suspension. The purpose of this research is to extract chemical and physical information from hyperspectral images, Near-Infrared Chemical Images or NIR-CI, of solid medications. These images have two spatial dimensions, xy-plane, and one chemical spectral dimension, z-axis. Existing analytical techniques do not provide spatial and structural information about the individual chemical components. This project is a collaboration between the Mathematical Science Department and the Analytical and Pharmaceutical Lab of the Chemistry Department of UPRM. Our idea is to develop mathematical and software tools to perform variogram analysis, particle spatial statistics and multivariate analysis of the hyperspectral images to study their heterogeneity and texture properties. The tools will be tested on real data obtained in the lab. This work will contribute to the development of better processes for quality control on pharmaceutical products.

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Santiago-Soto, Samuel

Damudt, Daniel - CCOM, UPR Arecibo; Castro, Emmanuel - CCOM, UPR Arecibo

Computer Sciences


As smartphones continue to evolve, we constantly find new ways to leverage their capabilities for the benefit of the worldwide community. In the case of this research project, it sought out to create a mobile application for the Android operating system that would be of benefit to the university's fellow students. The main purpose of the application would be to provide the students and faculty of the precinct with concise and accurate university information in a convenient and easy to use application form. Before beginning development of the application, extensive research was conducted in order to determine what the university's community desired as main features, on how these features would be designed and developed and what equipment would be needed to do so. Using the information of this research, the team decided the application would consist of two main components. These components are a map of the precinct's key locations and a university associations database. The application research and development team was then split into two sub-teams, one for each main section. These sub-teams dedicated the first semester of this three semester research project to develop the core foundations of each section and brought the application to a near beta stage. The application was then presented to the university's community so feedback would be received from their work. The entirety of the research and development team would like to present its advancements in the mobile application field to the research community.

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Torres-Colon, Yesenia

Arroyo, Monica - Pontifical Catholic University of Puerto Rico-Ponce

Computer Sciences

STRUCTURAL AND FUNCTIONAL BIOINFORMATICS ANALYSIS OF UNCHARACTERIZED PROTEINS OF LOA LOA

Loa Loa is a parasitic nematode that causes filariasis, a disease affecting about 170 million people in Africa, South America, and other subtropical regions. Filariasis can cause elephantiasis of the limbs and genitalia that leads to life-long disability and social stigma. Loa Loa can also cross into the subconjunctival tissues of the eye, causing pain. Current treatment for Loa Loa infection is diethylcarbamazine (DEC), which may cause encephalopathy and death, therefore it is counter indicated and the only treatment is surgery to remove the worms. The genome of Loa Loa was recently sequenced and is currently being annotated. A genome-wide sequence homology analysis was performed and found that over 4,000 putative proteins (predicted from open reading frames but have yet to be identified in vivo) of unknown function. The goal of this investigation is to predict the structure and function of some of these putative proteins to better understand its pathogenicity. Forty-two were analyzed with tools such as I-Tasser, Phyre 2, Dali Server, and Dali Lite to predict structure and function. There was a significant positive correlation between the analyzed hypothetical proteins and the models generated, and thirteen of these proteins have been successfully computationally characterized. The results may potentially assist computational ligand-binding studies, structure-based drug design, theoretical information about other investigations about this worm, and different programs to establish the structure and function of these proteins.

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Education

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Burgos-Aviles, Adrian Ernesto

Montes Gonzalez, Ingrid - Chemistry, University of Puerto Rico- Rio Piedras

Education

Laboratory Experience for the Organic Chemistry Course based on a greener approach for the Grignard Reaction

The environmental pollution that has accumulated from hundreds of years ago has reached alarming levels that are generating an environmental awareness. For that reason the concepts of green chemistry should be applied to new methods of research in the field of chemistry. Also, we must educate the future generations to redesign existing methods following the green chemistry concepts. This research is focused in the design of a greener Grignard experiment for the organic chemistry laboratory course, in which the steps that students are intended to take are through the simulation of research that is performed these days. This experience also allows the students to correlate and integrate different concepts learned throughout the organic chemistry course. This experiment aims to involve students in the process of creativity and critical thinking, through a greener synthesis of a tertiary alcohol using three different routes. To meet the green chemistry principles, the solvent used traditionally was switched for one that is less harmful to the environment and less dangerous. Also the amount of solvent was reduced and the need to maintain a nitrogen atmosphere is no longer necessary. The results obtained in terms of recovery were similar to those obtained with the original solvent thus showing that this method works. The synthetic methodology will be elaborated.

Camacho-Irizarry, Coralis

Medina, Zuleika - Chemistry, UPR-Cayey; Ortiz Nieves, Edgardo L. - Mathematics and Physics, UPR-Cayey

Education

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Development of a Hands-On Activity to Learn About Sugars

The increase of type II diabetes among children during the past few years has been of high concern, mainly due to the health risks associated with the disease. It has been known that a high consumption of simple carbohydrates or sugar is one of the main factors that can lead to the development of type II diabetes. Through deep understanding of the concept of sugars, children can create awareness that may lead them to make healthier choices and balance their food intake, avoiding increasing the risk of diabetes. Johnstones model suggests a teaching strategy to help students make interconnections between the three levels of representation: macroscopic, submicroscopic and symbolic. In this project a hands-on activity is currently being developed to aid middle-school students to better understand the concept of sugars. The activities will instruct students about the concept of sugars by exposing them to the three levels of representation described by Johnstones model.

Rivera-Reyes, Roberto

Mitchell, Bryan - Electrical and Computer's Engineering, UPR-Mayaguez; Alverio, Orlando - Electrical and Computer's Engineering, UPR-Mayaguez; Reyes, Gil - Electrical and Computer's Engineering, UPR-Mayaguez

Education

Nanotechnology Videogame for Middle School Students

Some middle school students experience a lack of interest to pursue college studies in Science, Technology, Engineering, and Math due to socioeconomic factors that affect their academic path. Throughout the last decade the field of nanotechnology has positioned itself in one of the most promising areas of science. In the past years, the UPRM CREST: Nanotechnology Center of Biomedical, Environmental, and Sustainability Applications have been working toward increasing the interest of students in STEM. UPRM CREST seeks to reach middle school students from schools at low income communities. Many studies demonstrate that gaming, in addition to its entertainment aspect, is an excellent medium to lower school dropouts and increase the probability of continuing undergraduate studies. Since gaming has shown potential value in education, this work's goal is to develop a nanotechnology video game accessible and appealing to middle school students to teach them about this subject. The game design has been divided into four different aspects: programming, graphic design, storyline,

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and music. In addition, the concepts of nanotechnology currently in development are ferrofluids and hydrophobic materials. As part of a preliminary study, a demonstration of an unfinished game level was presented to approximately one hundred students. Sixty six participants from the south and west area of Puerto Rico answered questions relevant for the game design and the students preferences toward video games. We will present the results of the first two levels of the game on the students from the CREST high school clubs and its effect in attitude of students toward the area of nanotechnology and STEM in general.

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Electronics

101

Ayala-De Leon, Genesis

Ramos, Idalia - Physics and Electronics Department, University of Puerto Rico at Humacao; Santiago, Jorge - Electrical and Systems Engineering Department, University of Pennsylvania

Electronics

Electrochemical Double Layer Capacitors with Carbon Composite Electrodes

Electrochemical double layer capacitors (EDLCs) are one of the most promising energy-storing devices due to their environmental friendliness, high power density, rapid charging/discharging ability, and long cycle life. In EDLCs, two electrodes are placed in an electrolyte and a voltage is applied between them. In the first phase of this research, the electrodes were prepared with a solution containing 90 wt% Activated Carbon (AC), and 10 wt% polystyrene (PS) in chloroform (CHCl3). An amount of 0.15 wt% Carbon Nanotubes (CNTs) and 1.5 wt% of the surfactant sodium dodecyl-benzene-sulfonate (SDBS) was added to the solution. A flexible and simple EDLC was constructed by inserting two electrodes coated to the nickel foam and a piece of filter paper between them (separator) inside a small seal bag with KOH (6 M) as the aqueous electrolyte. Its properties were analyzed using scanning electron microcopy (SEM), electrical conductivity measurements, and energy-dispersive x-ray spectroscopy (EDS). The capacitance of the EDLC was measured using the constant current discharge method. Results showed an improvement in the performance of the EDLC with CNTs. The addition of SDBS increased the conductivity of the electrode but the EDLC failed and no capacitance was measured. The second phase consisted in studying the influence of SDBS in the porosity of the electrodes. The percentage of PS added to the samples was reduced to 1 wt%. Their properties were analyzed using SEM, electrical conductivity measurements, and EDS. Results showed an increment of the electrodes porosity, but a readily reduction of its conductivity.

Flores-Nigaglioni, Anthony

Flores Nigaglioni, Anthony - Electrical Engineering, UPR Mayaguez; Contreras Ospino, Boris - Electrical Engineering, UPR Mayaguez

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Electronics

USE OF CONFORMAL MAPPING IN PREDICTING GATE-ENCLOSED MOSFET RESPONSES

Gate-enclosed MOSFETs are commonly used for extreme environments with constant radiation exposure due to its radiation tolerance. Because of its annular geometry, the models used in industry do not accurately represent what happens physically on the device. The source and drain are asymmetrical plus their radiation tolerance is not predicted by Cadence Tools simulation methods. An accurate model extraction can take months to complete, so a fast extraction method is needed. A method called conformal mapping is shown to extract parameters with increased accuracy for simulation. The mapping is performed using a Schwarz-Christoffel transformation. This allows the mapping of any arbitrary geometry into a well-known rectangular geometry. Additionally, every parameter that changes because of the geometry is recalculated for an accurate representation of short-channel effects and parasitic effects. The SPICE model automation is performed with a Keithley Sourcemeter 2612 using LABVIEW. A call operation is performed to MATLAB to calculate aspect ratio using the mapping transformation toolbox. Simulations of the extracted transistors are shown and compared with experimental current and voltage characteristic curves of annular devices.

Martinez-Milian, Luis

Martinez, Luis - Department of Physics and Electronics, University of Puerto Rico; Naylor, Carl - Department of Physics and Astronomy, University of Pennsylvania; Kybert, Nicholas - Department of Physics and Astronomy, University of Pennsylvania; Johnson, A.T. Charlie - Department of Physics and Astronomy, University of Pennsylvania; Pinto, Nicholas J. - Department of Physics and Electronics, University of Puerto Rico

Electronics

Dual input logic AND gate using CVD and exfoliated MoS2

A MoS2 thin film transistor having split gate architecture has been fabricated on a doped silicon/silicon nitride substrate and characterized. This device demonstrates AND logic functionality. The device functionality was controlled by applying either -

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10V or +10 V to each of the gate electrodes. When +10 V was simultaneously applied to both gates, the device was conductive (ON), while any other combination of gate voltages rendered the device resistive (OFF). The n-type carrier charge mobility in the ON state was 1 cm2/V-s and 2 x 10-2 cm2/V-s in the OFF state for the CVD MoS2 device. The device threshold voltage was also seen to shift from -8V to -10V. The low mobility could be attributed to the sharp contours of the MoS2 film due to substrate non-planarity. A significant advantage of this architecture is that AND logic devices with multiple inputs can be fabricated using a single MoS2 channel with multiple gates.

Serrano-Garcia, William

Nicholas J. Pinto - Department of Physics and Electronics, University of Puerto Rico-Humacao; Carl H. Naylor - Department of Physics and Astronomy, University of Pennsylvania; Nicholas J. Kybert - Department of Physics and Astronomy, University of Pennsylvania; A.T. Charlie Johnson - Department of Physics and Astronomy, University of Pennsylvania

Electronics

Facile fabrication of a UV tunable MoS2/p-Si junction diode

CVD grown MoS2 single crystals were transferred onto the edge of a p-Si/SiO2 wafer forming an abrupt heterogeneous junction diode at the MoS2/p-Si interface. When electrically characterized as a field effect transistor, MoS2 exhibits an n-type response and can be doped in the presence of UV light. As a diode it operates satisfactorily in air, but has higher currents in vacuum with a turn on voltage of ~1.3V and an on/off ratio of 20 at ± 2V. UV irradiation increases the diode on state current, decreases the turn-on voltage and reduces the ideality parameter below 2. These changes are reversible after annealing in air for a few minutes as desorption of electron trapping species like O2- and H2O- are believed responsible for this effect. A circuit integrating this diode was used to rectify a 1 kHz signal with an efficiency of 12%. Its simple design coupled with the ability to rectify AC signals, sense UV light and reversibly tune these diodes makes them inexpensive, multifunctional and usable as active or passive circuit components in complex electronics.

104

Engineering

105

Barreto-Rodriguez, Erick

Pagan-Torres, Yomaira - Department of Chemical Engineering, University of Puerto Rico-Mayaguez

Engineering

Design of a Cost Effective Atomic Layer Deposition Reactor

In this work, we present a detailed design of a cost-effective atomic layer deposition-ALD reactor for the synthesis of multifunctional nanostructured catalyst. The design of the ALD reactor was based on industrial and laboratory scale ALD systems used in the field of electronics for thin film deposition. Here, we demonstrate design parameters used for the ALD reaction chamber to ensure the uniform coating of particles. In addition the operation of essentials components of the system such as mass flow controllers, automatic block valves, pressures transducers, temperature controllers, and the analytical equipment to ensure control of the ALD reaction sequence will be presented.

Betances-Irlanda, Rebecca

Calderon, Eric - Engineering Science and Materials, UPR-Mayaguez; Carmona, Jose - Chemistry, UPR-Mayaguez; Perales, Oscar - Engineering Science and Materials, UPR-Mayaguez; Melendez, Enrique - Chemistry, UPR-Mayaguez

Engineering

Synthesis and Cytotoxicity Assessment of CdSe-based Quantum Dots on MCF-7 Breast Cancer Cell Line.

Quantum Dots (QDs) are semiconductor nanocrystals in the 2-12 nm size range. They exhibits quite interesting size-dependent properties such as strong quantum confinement and broad excitation conditions: owning intrinsic ability to generate cytotoxic species. On the other hand, photodynamic therapy (PDT) is a treatment that uses photosensitizing agents, along with light to kill cancer cells. Current

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therapy limitation strives on PDT being a local treatment, and the unavailability to be used to treat hard-to-reach cancer. The photo-excitation of QDs could produce localized necrosis in cancer cells and finally the destruction of the tumor. Thus, Cd-based QDs shows a great promise in cancer treatment by improving the effectiveness of PDT conventional regimes; however, a precise control in their water-dispersability and size and monodispersity at the nanoscale is an indispensable requirement. QDs nanoparticles were produced by microwave assisted aqueous synthesis and different reaction times. XRD characterization indicated that size of CdSe nanoparticles could be increased just by prolonging reaction times at a fixed temperature. Cytotoxicity will be evaluated by MTT cell proliferation assay and using an UV-Spectrophotometer. Ten-thousand MCF-7 breast cancer cell line will be seeded on four well plates. IC-50 values will be determined after 24 hours and 48 hours of initial QDs cell transfection.

Castro-Alvarado, Catherine Lee

Castro Alvarado, Catherine Lee - Chemical Engineering, University of Puerto Rico Mayaguez-Campus; Tirado Rijos, Angelica - Chemical Engineering, University of Puerto Rico Mayaguez-Campus; Fernandez Alos , Victor - Chemistry, University of Puerto Rico Mayaguez-Campus; Roman Velazquez, Felix - Chemistry, University of Puerto Rico Mayaguez-Campus

Engineering

Synthesis of Chitosan Magnetic beads for removal of estrogenic hormones in aqueous solution.

Synergistic effects between the synthesis of magnetite Fe3O4 nanoparticles with chitosan protonated and non-protonated beads can be used in multiple fields such as environmental remediation, drug targeted-delivery systems, magnetic resonance image enhance, and therapeutic administrations among others. Thus, the objective in this investigation was to design simple automated process for production of chitosan/Fe3O4 beads. In an effort to test the synthesis model methodology, different forms of chitosan surface functionality were selected from structure-behavior, environmental cost-effective to energy related processes (e.g. wastewater treatment plants). Trace level of endocrine disrupting compounds (EDCs) on effluent discharged from wastewater treatment plant to environmental water systems had been observed. EDCs are defined as emerging contaminants, which are subdivided on steroid hormones, pesticides, polycyclic aromatic hydrocarbon (combustion), and pharmaceutical and personal care products. According to

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literatures estrogenic-EDCs with high estrogenic-activity in water systems were obtained from estrogen, 17?-estradiol, and 17?-ethynylestradiol. Integrated bionanocomposite such as chitosan/Fe3O4 magnetic beads with conventional wastewater treatment techniques for the removal and degradation of EDCs. In this research project steroid endocrine hormones was evaluated. The magnetic properties enable the recovery of chitosan/Fe3O4 bead adsorbents, thus reducing operational cost in treatment water facilities. Furthermore, cutback on the use of expensive no-reusable adsorbents and endorsed several advantages of chitosan magnetic beads for remediation practices.

de Jesús-Lopez, Manny

Soto, Sujeily - Department of Mechanical Engineering, University of Puerto Rico, Mayagüez, PR; Rodríguez, Marcos - Department of Chemical Engineering, University of Puerto Rico, Mayagüez, PR; Suarez, O. Marcelo - Department of General Engineering, University of Puerto Rico, Mayagüez, PR

Engineering

Study and Characterization of Chitin Bamboo Composites

In the last decade, environmentally safe materials have been of great interest for the scientific and engineering community, such is the case of chitin and bamboo. Naturally, biomaterials are abundant and inexpensive, and their mechanical properties, very distinct. Hence, a combination of their relative strengths should be brought together to produce a suitable material for applications demanding higher strength. Throughout the last months the project hinged on information on how to enhance a constructive interaction between a chitin matrix and bamboo fibers. Chitin can be found in arthropods and fungal cell walls making it the second most abundant biopolymer, with high tensile strength, antimicrobial properties, biodegradability and biocompatibility, which are of interest in textile industries, biomedicine, food, and cosmetics. Bamboo belongs to the Gramineae family and is one of the fastest growing plants. The internal structure is primarily composed of two types of cells: sclerenchyma and parenchyma cells. These provide sufficient compressive and tensile strength for bamboo to be used as building materials. Currently, the interaction between these two materials is being investigated in the laboratory by chemically dissolving selected amounts of chitin and physically dispersing given amounts of bamboo strands in the solutions. Afterwards, the composites are placed in an oven to dry in order to remove the solvent. The ongoing work this semester is the characterization of the mentioned composites

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through thermomechanical analysis, differential scanning calorimetry, optical microscopy, and nanoindentation.

De Jesus-Silva, Jorge

Aviles, Amarillys - Civil Engineering Department, University of Puerto Rico, Mayagüez, PR; Hernandez, Liliana - Civil Engineering Department, University of Puerto Rico, Mayagüez, PR; Nazario, Gerardo - Civil Engineering Department, University of Puerto Rico, Mayagüez, PR; Laracuente, Luis - Mechanical Engineering Department, University of Puerto Rico, Mayagüez, PR; Suárez O. Marcelo - General Engineering Department, University of Puerto Rico, Mayagüez, PR; Tarafa ,Pedro - Civil Engineering Department, University of Puerto Rico, Mayagüez, PR

Engineering

Photo-degradation of Atrazine with TiO2 deposited in Recycled Glass Filter

Soil pollution is a major problem typically caused by agricultural activities that release toxic pesticide chemicals to control pests. The residuals of these pollutants are found in ground water sources and drinking water supplies. The main goal of this research was to study the feasibility of the fabrication of porous glass sheets embedded with photo-catalytic TiO2 for the degradation of atrazine as soil pollutant. The porous filter was fabricated by sintering recycled clear glass powder (MG-30 grade) with TiO2 nanoparticles between 750ºC to 800ºC for 20 to 30 minutes. Water percolation was measured by recording the elapsed time to obtain a given water volume. The composite is influenced by sintering parameters, it was necessary to determine whether the sintering temperature and time had an effect in the TiO2 phase transformation and photo-activity. X-ray diffraction analysis allowed determining the TiO2 polymorph i.e. anatase or rutile, after the TiO2-glass composite was sintered. Preliminaries results demonstrate a reduction of percolation rate when the temperature and the time increase. Also, the anatase polimorph remains for the sintering temperature used. Ongoing experiments seek to study the photo-activation of TiO2 with ultraviolet light lamp sources and the degradation of atrazine. A High Performance Liquid chromatographic (HPLC) analysis is being used to evaluate the degradation and viability of applying the material in soil treatment technologies.

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De Jesus-Villanueva, Nerida H.

Cotto, Irmarie - Deparment of Civil Engineering and Survey, UPR-Mayaguez; Padilla, Dra. Ingrid - Deparment of Civil Engineering and Survey, UPR-Mayaguez; Torres, Perla - Deparment of Civil Engineering and Survey, UPR-Mayaguez

Engineering

Efficiency Study and Optimization of EPA Method 8270D for Determining Concentrations of Di(2-ethylhexyl) Phthalates (DEHP) by Gas Chromatography/Mass Spectrometry

An ongoing environmental study to evaluate if a link exists between exposure to hazardous chemicals and high rates of preterm birth is underway by The Puerto Rico Testsite for Exploring Contamination Threats Center (PROTECT). Di(2-ethylhexyl) phthalates (DEHP) is a cost-effective general purpose plasticizer used across a range of applications. This chemical has been associated with preterm birth as well as other health threats, fostering concerns for the safety of the general public and encouraging studies on the repercussions of their wide use in manufacturing. The Environmental Protection Agency (EPA) method 8270D was adopted and modified by the UPRM Environmental Engineering Laboratory in order to analyze the concentrations of DEHP in water and meet PROTECT research objectives. To support the data obtained with the modified UPRM procedure, the original EPA method for liquid-liquid extraction and analysis with a GC/MS was replicated. Known concentrations of DEHP in water where extracted in order to obtain its efficiency and later compared with the UPRM modified method’s results. A total of two sets (A, B) where performed with triplicates. Results indicate decreased efficiencies as concentrations increase and reveals peak efficiencies at concentrations below 0.02mg/L. Although there are significant variables that impact our results, when comparing both method’s efficiencies we see a common trend. In conclusion, the effectiveness of both methods to extract DEHP concentrations in water diminishes considerably above 0.02mg/L and a cost study showed considerable savings with the UPRM method (more than half) by reducing waste and diminishing exposure of Dichloromethane solvent to analyst.

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Diaz-Marquez, David R.

Montanez Vazquez, Wilfredo - Electrical and Computer Engineering Department; Rojas Martinez, Jonathan R. - Electrical and Computer Engineering Department

Engineering

Reverse Recovery Charge Measurement Automation

The speed at which a device turns off is directly proportional to the reverse recovery charge, Qrr: the amount of charge accumulated within the Device Under Test, DUT. The stored charge builds up in the base region when a diode is subject to a forward current, at the inversion of the electric field polarity the diode should turn off. To do so, the accumulated charge must be removed before the diode can be returned to the off state. The automation of the Qrr measurement was accomplished using LabView. The DUT is connected to a test box, a Keithley 2612 power supply and ArbStudio waveform generator are used as stimulus, and the circuit response is detected by a LeCroy oscilloscope. As method of verification, the current curve is plotted. This curve is then integrated with respect to time to obtain Qrr. This project presents the reverse recovery charge measurement or Qrr test, its importance, and its significance in device characterization. The project focuses on ways to significantly reduce the time to market and overall cost by presenting an automated solution easily exportable to the industry.

Figueroa-Ocasio, Christian

Zapata, Raul - Civil Engineering Department, University of Puerto Rico, Mayaguez; Pabon, jose - Civil Engineering Department, University of Puerto Rico, Mayaguez; Hernandez, Jean - Civil Engineering Department, University of Puerto Rico, Mayaguez

Engineering

Flood Mitigation Using Hydraulic Approaches at Converging Flows in Open Channels

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Inadequate convergence between the flows from main stormwater sewer system of University of Puerto Rico at Mayaguez and Quebrada de Oro creek trapezoidal concrete channel is one of the reasons for the recurring flooding problem in our main student parking lot. Climatology data shows that precipitation resulting from a 24-hr duration with 2-year recurrence events as well as many short duration heavy rainfall events may surpass the 45 years old original design capacity of the current drainage system. The creeks high water level limits the parking lot drainage capacity to a minimum causing the flooding conditions. A hydraulic analysis of two possible flood mitigation alternatives is under development. The initial alternative considered is to split the creek channel in two reaches using a 13 meters long, 3 meters high concrete wall that protects the outlet drainage flow by means of moving the converging flow as a parallel flow at a downstream point in the channel and the expansion of the current concrete channel section at the contraction areas to prevent chocking. HEC-RAS hydraulic modelling of the existing and proposed channel conditions were develop by using Standard Step Method procedure and Energy Balance at the flow convergence. Results show that there is still a 16 centimeter backwater effect, which is 10 centimeters above the maximum established limit and the culvert drainage water level is above the outlet top elevation, which could result in blockage of the stormwater collected through campus. Therefore, further studies are needed to properly design this flood mitigation system.

González-Lopez, Lorelis

Martínez-Iñesta, María M. - Chemical Engineering, UPR-Mayagüez

Engineering

Synthesis of transition metal substituted zeolites for biomass conversion

Zeolites are microporous crystalline solids whose properties depend on their framework. Zeolite beta has large pores and high acidity which gives it great catalytic properties. Isomorphously substituting zeolite beta with transition metals has been proven to enhance its capacity as a catalyst but current methods partially destroy the structure. Our goal is to incorporate tin into the framework of the Zn analog of the zeolite beta, CIT-6, and isomorphously substituting the Zn with Sn using acid leaching. This method should be less destructive than current methods. This semester the synthesis of zeolite CIT-6 was attempted by following reported methods and the samples were treated with acid leaching and calcination. XRD

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analysis showed that the zeolite synthesized was VPI-8 with some CIT-6 impurities. Results of both calcined and acid leached samples suggest the successful removal of organics used in the synthesis. However the XRD of the calcined sample also suggests partial destruction of the structure. The synthesis temperature, time and reactant concentracions will be changed to obtain zeolite CIT-6.

González-Medina, Abimael

Abimael González Medina - Electrical Engineering, UIA-Bayamon; Michael,J Moralez Otero - Electrical Engineering, UIA-Bayamon; Prof. Amilcar Rincón Charris - Mechanical Engineering, UIA-Bayamon

Engineering

Magnetorquer driver for cubesat development

This presentation aims to provide knowledge about the analysis and operation of a circuit of magnetic torques which is essential in the design of a cube or small satellite. The basic operation of a magnetorquer is applying a magnetic torque in the desired direction using the lowest possible power in order to stabilize the cube satellite or launch vehicle, when being released into the atmosphere. Will be presented the whole process of designing a PCB and all related standards in its development . It is hoped that this presentation will provide a basic understanding of the operation of a circuit magnetic torques from analysis to implementation of the PCB.

Iravedra-Rodriguez, Veronica

Barajas, Ulises - Civil Engineering, UPRM; Suarez, O. Marcelo - Engineering Science and Materials, UPRM

Engineering

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On the Modeling of Deformations of Layered Composites Using Abaqus

Micro electronic mechanical systems (MEMs) are a technology that advanced the study of thin films intended for a breadth of applications. In the present research, thin films are produced using magnetron sputtering furbished with targets made of pure aluminum or an Al-4 %wt B composite material. Silicon wafers and glass were used as substrates. The films mechanical properties were examined through nanoindentation. The modeling of this process is currently being performed with finite element analysis (FEA). We are utilizing Abaqus, a FEA simulation software, to study nanoindentation models on a film with the goal of observing the deformation and the stress state produced in the material. In addition, the substrate effects are studied. Diverse 2D models were created with different indenter shapes and with various mesh configurations. The modeling outcome will be compared with the experimental results.

Lopez-Marcial, Gabriel

Dávila, Manuel - Mechanical Engineering, UPR-Mayaguez; Diaz-Rivera, Rubén - Mechanical Engineering, UPR-Mayaguez

Engineering

HIGH-THROUGHPUT SINGLE-CELL ELECTROPORATION WITH GEOMETRICALLY INDUCED PULSES

Electroporation is the process of applying a small voltage to a cell membrane to permit the exchange of cellular material. Our goal is to create a microfluidic channel in which electroporation may be induced to single cells flowing through. Polydimethylsiloxane (PDMS) microchannels consisting of a wide section followed by a number of alternating narrow and wide sections (traps) were fabricated using soft lithography and permanently bonded to a glass slide. AgCl electrodes at the inlets and outlets of the channel permitted electrical activity to be monitored within the channel by being connected to a potentiostat equipped with Gamry software. Channel resistance was calculated theoretically using a MATLAB program and compared to experimental results obtained with a channel filled solely with a static conducting liquid called Phosphate Buffered Saline (PBS), as well as with the same liquid flowing through it. Human mammary cancer cells (MDA-MB-231) were inserted through the channel using a syringe pump with low volumetric flow and

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were observed to transit easily through the aforementioned traps, due to deformation facilitated by the high speeds created by the cross sectional reduction. Each cell that flows through a single trap is expected to increase the resistance measured through the channel (~10M?) by a value of 78-97.5k?. When these resistance changes are reflected in the experimental response, it means the cell will have gone through while having a voltage applied. Future experiments will study these electrical responses to cell transit to be compared with our theoretical calculations.

Marrero-Vazquez, Michellle

Rivera, Christian - Chemical Engineering, UPR-Mayaguez; Padilla, Nitza - Chemical Engineering, UPR-Mayaguez; Oyola, Oscar - Chemical Engineering, UPR-Mayaguez; Pagan, Yomaira - Chemical Engineering, UPR-Mayaguez; Cardona, Nelson - Chemical Engineering, UPR-Mayaguez

Engineering

Solvent Effects in the Catalytic Conversion of Fructose to Lactic Acid

Lactic acid is an industrial bulk chemical with production higher than 300,000 metric tons per year in 2010. Due to its high versatility and importance as a platform chemical it is forecasted that its market demand will increase in the following years. Current lactic acid production from fermentation routes will not be able to satisfy the forecasted demand due to technical challenges such as high side production of salts as by products and slow production rate. In this work we demonstrate that the combination of a Sn-Beta zeolite with mainly Lewis acidity prepared using a post-synthetic procedure and a solution of GVL and water as solvent is an effective catalytic process for the production of lactic acid from fructose. Highly crystalline Sn-Beta zeolite catalyst was synthesized with a surface area of 536 m2 g-1 and contains both, aluminum and tin atoms incorporated in the structure. The results indicate that when the reaction is conducted, using Sn-Beta, in GVL:H2O there is an almost three-fold increase in the initial fructose conversion rate and a four-fold increase in the production rate of lactic acid when compared against using only water as a solvent. Therefore the use of Sn-Beta zeolite prepared using a post-synthetic procedure amenable to scale up and GVL:water as solvent offers a viable pathway for the conversion of fructose to the commodity chemical lactic acid in high yields.

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Martinez-Perales, Cristian

Fabio Alape Benitez; Miguel Galarza Rodriguez

Engineering

EVALUATION OF MECHANICAL PROPERTIES OF GALVANIZED STEEL BY IMMERSION

Galvanized steel combines long life with minimal maintenance and a low cost system that provides both corrosion protection and physical-mechanical performance that meet many requirements of the modern construction systems needs such as strength, strain and easy application. In this project, an evaluation consisting of determine the following: weight of coating, yield strength, tensile strength and elongation, are being measured for commercial samples of a local producer of steel. As a first approach, all standards related to the evaluation have been reviewed under the ASTM Standards A653, A924, A370. Calculations of the minimal requirements of force to perform the mechanical test were developed and a typical instrument was selected. Also, sample sites were determined and the next step is to define the number of samples and tests to do.

Martinez-Rodriguez, Rafael

Michelle Marrero Garcia - CROEM High School; David Florian - UPR-Mayaguez; O.Marcelo Suarez - General Engineering, UPR-Mayaguez

Engineering

Effect of NbB2 nanoparticles on the Portevin-Le Chatelier phenomenon in Al-Mg alloys

This research focuses on the study of the Portevin-Le Chatelier phenomenon in Al-Mg alloys. Such phenomenon is caused by the interaction between moving dislocations and the solute atoms present in a solid solution. Portevin-Le Chatelier is observed as serrations in the plastic deformation region of stress-strain curves.

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The phenomenon affects most mechanical properties upon plastic deformation, such as ultimate tensile strength and ductility, as well as cosmetic damages, posing problems for industries which commonly use Al-Mg alloys. The alloy was melted into rods that were cold-rolled into wires and divided into three sets: one was left as control, one was given a solution treatment and the third was given a solution and aging treatment. Tensile tests were conducted on the Al-Mg wires with and without NbB2, as to analyze the effect of the nanoparticles. The preliminary results showed that the phenomenon is indeed observable, but only in the samples of the two sets with the solution treatment and the solution, aging treatment. The nanoparticles affected the phenomenon but not necessarily diminishing it. Future research seeks to eliminate some inconsistencies in the results to better understand the effect of nanoparticles with the ultimate goal of diminishing the effect.

Mendible-Barreto, Orlando

Mendible, Orlando - Investigacion, Centro Residencial de Oportunidades educativas de Mayaguez; Soto, Hildelix - Ingenieria Civil, UPRM

Engineering

Relación de la resistencia a compresión y flexión del hormigón de alta resistencia con reemplazo de cenizas volantes y nanosílice

In this investigation we studied the mechanical behavior of high strength concrete with replacement of fly ash and nanosilica. It was done with the aim of finding a concrete mix that was eco friendly and at the same time , had a high strength . Five different mixtures of high strength concrete were performed with different proportions of fly ash and nanosilica . With each of the mixtures bending and compression tests were made with concrete that had been cured seven and twenty-eight days. The data reveals that mixtures possessing fly ash and nanosilica had a similar strength with the concret with no additives. By comparing the experimental data with the control mixture mixtures observe that the use of fly ash and nanosilica influences the strength of the concrete . In conclusion, the third blend was the most resistant, as this had greater amount of nanosilica and had no fly ash. Also, we conclude that the use of nanosilica and fly ash provides the high strength concrete the flexural strength characteristics and equal to the regular concrete compression, however, we could get a concrete eco friendly. For future work we intend to conduct a statistical analysis between the relationship between flexural strength and compression.

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Millet-Ayala, Alexander

Pérez-Pérez, Maritza - Chemical Engineering, University of Puerto Rico Mayagüez Campus; Suleiman-Rosado, David - Chemical Engineering, University of Puerto Rico Mayagüez Campus

Engineering

Sulfonation and Characterization of Poly(1,4-phenylene ether-ether-sulfone) (PEES) and Polyphenylsulfone (PPSF) for Fuel Cells and Specialty Separation Applications

Commercial copolymers such as Poly 1,4-phenylene ether-ether-sulfone, known as PEES, and Polyphenylsulfone, known as PPSF, are being considered due to their potential as proton exchange membranes. Their capacity to be sulfonated and the presence of ether groups in their backbone could create synergistic effects for the transport of protons that could potentially be better than the state of the art Nafion® membranes. As an objective for this research, a method to wash these polymers after sulfonation is suggested to minimize the loss of sulfonated polymer due to the gel-like nature when it is hydrated. Patiently washing the sulfonated polymers with 4 liters of deionized water per 5 grams of product, and then drying it in an oven for two days resulted in small losses of the product, comparing to methods that used increased amounts of deionized water per product. Fourier transform infrared spectroscopy comparison of dry and hydrated counter-ion substituted sulfonated PEES membranes show that there was a shift of characteristic bands to a lower wavenumber when the membrane is hydrated due to hydrogen bonding. This could be related to the unique interactions of water with the sulfonic and ether ionic domains in the polymer. Small-angle X-ray scattering experiments were conducted for the hydrated and dry states to further understand the changes in the nanostructure with the incorporation of water. A quantifiable shift in the scattering vector was observed, showing that the distance between atoms was increased when membranes were hydrated.

Navarro-Perez, Daniel

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Mendez, Jean - Computer Engineering, University of Puerto Rico Mayaguez

Engineering

Cybersecurity on Unmanned Aerial Vehicles

The security of our country is constantly being threatened. In order to ensure protection for our society, it is necessary to detect vulnerabilities in critical devices before terrorist or other adversaries are able to exploit them. Part of these vulnerabilities can be solved by improving the device’s software and communication configuration. An example of this are Unmanned Aerial Vehicles (UAV). The technologies currently implemented on these devices support several types of wireless communications for navigation and other appliances. The UAV can be used for many civilian applications such as: environmental monitoring, law enforcement missions, entertainment recording/broadcasting, and mail transportation, in addition to other applications. The focus of this work is using Cybersecurity on Unmanned Aerial Vehicle devices as a possible implementation that is more secure for future systems. In an example environment, an attacker may have a set of software and radio frequency (RF) tools that will help the penetration testing process.

Nieves-Rosado, Luis

Cordova-Figueroa, Ubaldo - Department of Chemical Engineering, UPRM

Engineering

Effective Reaction Rate of An Anisotropic Catalytic Particle Subject to a Constant Fluid Flow

An important class of biological and industrial chemical reactions are diffusion controlled. The speed of these reactions is controlled by the rate that reactants reach the reactive site. A method to control the speed of these reactions is to assist or impede the diffusion of reactants with an external fluid flow. To study this possibility, much research has been made in the transport of reactants around spheres subject to external flows. Most of these studies focus on isotropic particles, which are either completely reactive or non-reactive. However, real catalyst are anisotropic, having more complex geometries and only some truly reactive patches.

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So far, there seems to be little research into the effect of fluid flow to transport around anisotropic spheres. We study the effectiveness of the reaction, quantified by the effective reaction rate, of an anisotropically reactive sphere under external flow. The area of the sphere that is catalytic can vary axisymmetrically, from non-reactive to fully reactive. The external fluid flow is uniform and can take any relative orientation to that of the sphere. The strength of the surface reaction is controlled with a Damkohler number, while the strength of the flow is controlled with a Peclet number. We use perturbation and finite difference methods to maximize the effective rate constant by varying these, the relative orientation and the area of the sphere that is catalytic.

*Oquendo-Rosa, Emmanuel

Dr. Vijay Goyal - Mechanical Engineering Department, University of Puerto Rico, Mayaguez Campus

Engineering

Understanding Bone's Biomechanical Behavior

In Fall 2014, Dr. Goyal proposed me a very interesting research work. The project consisted in developing a bone fracture and regeneration numerical model at the cell level using mesh free techniques such as peridynamics. With this said, we came up with an action plan to familiarize with the topic. I began to conduct an in-depth literature review that will help me grasp the theoretical foundation of bone’s biological behavior. This survey has shown me that there is very little progress in this field and thus my contribution would be a groundbreaking work, if successful. The first step was to study the anatomy and physiology of bones. Then, I studied the mechanobiological processes that occur after a bone fracture and that are part of the regeneration biological phenomena. Also, the novel mathematical methods being developed to model these bioregulated processes were reviewed and assessed. Furthermore, I applied the knowledge gained in materials science to understand bone mechanical properties relative to the properties of inorganic materials. I investigated the rare combination of strength and flexibility of a bone, and found that they are defined through the mechanical interaction between bone constituent molecules, hydroxyapatite and collagen. For this topic, the current “in silico” experimental methods were assessed. Finally, I am currently focused in the molecular level of bone complex hierarchical structure in order to complete a bottom-up assessment of how it describes bone macroscopically. This analysis includes a cell molecular biology review and a study of intercellular interactions.

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*Oquendo-Rosa, Emmanuel

Morales, Nestor - UPR-Mayaguez; Rosario, Joannette - UPR Mayaguez; Arocho, Fernando - UPR Mayaguez

Engineering

Tarzan Watch – Campus Safety with a Smartphone App

Tarzan Watch Smartphone App Research Project contributes to the university community safety. The specifications for the problem definition were obtained from meetings with campus stakeholders including the Campus Safety Department, the Student Council, and the administration of the Technology Information Center of UPRM. It was found that the university community was avoiding night activities and changing their study patterns after a series of criminal incidents. Furthermore, we identified a big disproportionality between “scared students” and crime victims and/or witnesses due to a high-risk perception caused by one criminal incident with high levels of media attention.

Tarzan Watch App features action and prevention methods. Action methods provide improved ways of communicating with Campus Safety Department after criminal incidents such as automatic alarms, user’s geolocation and one click help. In addition to, the user will also have the option of sending text messages to alert his contacts about the incident. Prevention methods use the data produced by the application usage to analyze the current “danger-zones”.

The Non-Light-of-Sight (NLOS) Conditions of the physical space of UPRM present a challenge for the geolocation feature. A number of solutions taking advantage of the local network of the university campus such as Wi-Fi Received Signal Strength Indicators (fingerprinting, triangulation) and access point connection have been considered. The latter would correlate the connection of users to access points with their location within a building. This method is currently being validated. The results of the implementation of Tarzan Watch Smartphone App will be presented at the talk.

Ortiz-Merced, Carolyn

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Amarilis Declet - Mechanical Engineering, UPR Mayaguez; Nelson Sepulveda - Electrical Engineering, UPR Mayaguez; Javier Martinez - Mechanical Engineering, UPR Mayaguez; Oscar Marcelo Suarez - General Engineering, UPR Mayaguez

Engineering

Synthesis and Characterization of Bio-ferroelectric Composites

Environmentally conscious scientists and engineers have been working on research of bio-based sustainable alternative materials. The present study of bio-ferroelectric composites could have potential applications in electronics such as smart cards, capacitors, and sensors. These materials are nontoxic, biodegradable with a cost effective fabrication method. This research involves the development of a bio-composite made of a chitosan and cellulose matrix in which the effects of cellulose and acetic acid concentrations have been evaluated. For the fabrication of the bioferroelectric composite, a chitosan-cellulose layer is synthesized followed by a layer containing ferroelectric nanoparticles. The bio-composites underwent thermogravimetric, thermomechanical and tensile test analysis. Our preliminary results demonstrated that higher amounts of cellulose decreased the mechanical and thermal properties of the composites.

Ortiz-Ortiz, Alondra

Ortiz-Ortiz, Alondra M. - Mechanical Engineering, University of Puerto Rico, Mayaguez Campus; Medina-Aviles, Lourdes A. - Industrial Engineering, University of Puerto Rico, Mayaguez Campus

Engineering

Evaluando las necesidades de pacientes con neuroestimulador

El proposito de este trabajo es estudiar a fondo la enfermedad del Sindrome de Dolor Regional Complejo (CRPS por sus siglas en ingles) o Distrofia Simpatica Refleja (RSD) e investigar como el tratamiento con neuroestimulacion contribuye al mejoramiento de la misma. El Sindrome de Dolor Regional Complejo es un trastorno de dolor cronico, producto de un disfuncionamiento del sistema nervioso. Se trata de senales descontroladas de dolor que el sistema nervioso le envia al cerebro. La terapia con neuroestimulacion consta de utilizar un dispositivo

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encargado de bloquear dichas senales, con el fin de que las mismas no puedan llegar al cerebro. Datos cientificos indican que la terapia con neuroestimulacion es el tratamiento mas efectivo para dicha condicion de dolor cronico. No existe una cura para el CRPS, por lo que el tratamiento de esta enfermedad consiste en aliviar los sintomas presentados por los pacientes. De aqui la principal motivacion para llevar a cabo esta investigacion, llevar al portador, es decir, al paciente de CRPS que utiliza la terapia de neuroestimulacion como tratamiento, al disfrute de una mayor calidad de vida. Para esto se realiza una encuesta a pacientes que padecen de esta enfermedad con el proposito de evaluar las areas de oportunidad del neuroestimulador. Como trabajo futuro y de acuerdo a los resultados de la encuesta se estara evaluando el diseño del neuroestimulador desde el punto de su funcion y de su estructura, lo que incluye sus componentes y atributos (material, tamaño, etc.).

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Ortiz-Tirado, Jean

Stephany Herrera - Chemical Engineering, UPR-MAYAGUEZ; Barbara Calcagno - General Engineering, UPR-MAYAGUEZ; Aldo Acevedo - Chemical Engineering, UPR-MAYAGUEZ

Engineering

Characterization of Mechanical Properties of Liquid Crystalline Elastomers

Liquid crystalline elastomers (LCEs) are structurally anisotropic materials that can experience large reversible deformations and fluctuations in their physical and mechanical properties when exposed to external stimuli (i.e. change in temperature, light radiation and electric or magnetic fields). As such, they have potential applications in sensing, and actuation, as well as in bioengineering as substrates for tissue culture, and for muscle and ligament replacements. Polysiloxane-based magnetic sensitized liquid crystal elastomers composites have been prepared by introducing chemically functionalized magnetic nanoparticles. The resultant elastomers reveal a nematic phase and are monodomain with uniform orientation of the anisotropic mesomorphic molecules, after imposing a constant load during their crosslinking step. Since LCEs are anisotropic materials they reveal anisotropic properties such as elastic Young’s moduli. Nevertheless, characterizing and understanding the effect of different formulation parameters on these anisotropic properties is crucial for optimizing their final performance. Therefore, different mechanical properties, including Young’s moduli, Ultimate Tensile Strength and toughness, are evaluated using an Instron ElectroPulse model E3000, for LCE samples with and without magnetic particle inclusions. Finally, results for static and dynamic tests varying experimental conditions such as temperature and crosshead speeds will be presented.

peralta-trinidad, pedro

Gerardo Carbajal - Mechanical Engiieering, Turabo University

Engineering

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THERMOELECTRIC GENERATOR DEVICE FOR COOLING APPLICATIONS

For this research a thermoelectric array were used to experimentally investigate whether or not the energy consumption of this device can cause a cooling process in the hot fluid. For this purpose an experimental setup was designed in which a square channel allows the fluid flow of cold and hot air. Hot air was pumped at the bottom section and cold at the top section; the two fluids were separated by a wall. The heat source had a maximum capacity of 1850Watts and the electrical loads used in the experiments were in the range between 390ohms and 760ohms. It was found that the temperature difference between the inlet and outlet of the hot air was affected by the application of an electrical load. Even though significant data were evaluated, there are still ambiguous results that should be further evaluated.

Rivera-Collazo, Cesar

Niño, Esmeralda - Industrial Engineering, University of Puerto Rico Mayaguez Campus; Cabrera-Rios, Mauricio - Industrial Engineering, University of Puerto Rico Mayaguez Campus

Engineering

Multiple Criteria Optimization: Structural Design and Prototyping using 3D Printing

There is a need to optimize interlocking structures to provide a wider range of applications and decrease the complexity of the studies. This work aims to define the efficiency frontier of an interlocking structure by developing a multiple criteria optimization problem using Box-Behnken Design of Experiment and Data Envelopment Analysis. We set critical design parameters and sample size according to the performance under study which was structure maximum load and weight. The interlocking elements were created using 3D printing. This project will lead to optimization studies of interlocking arrays with variable element geometry and material combination. Also with the recent developments of 3D printing this will be accessible to almost anyone providing prototyping precision while simplifying such structures studies.

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Rivera-Colon, Bryant

Collazo Irving - Electrical Engineering, UPR Mayaguez; Figueroa Yolanda - Electrical Engineering, UPR Mayaguez

Engineering

Desing of a Crossover Network and Acoustic Characterization of an Audio Loudspeaker

In a typical speaker, there are a number of drivers, each with its own frequency range. The woofer reproduces the lowest frequencies, the midrange the middle frequencies, and the tweeter the highest. Typical speakers have either two or three drivers. A speaker with two drivers would have a woofer/midrange and a tweeter, and a three driver speaker would have a woofer, midrange and tweeter. A crossover network is used to divide the incoming signal and send it to the proper driver. In a system with three drivers the division of frequencies is from about 20-400Hz, 400-3000Hz, and 3000-20kHz respectively for the woofer, midrange and tweeter. The design of the crossover network is not as simple as it may first appear. This is because of the many acoustical properties that must be taken into account. First, the filtering inherent in the driver used must be taken into account when designing the filter to have the desired lowpass, bandpass or highpass characteristics. Also, the configuration and physical mounting of the drivers must be accounted for so that the acoustic wave integrates correctly as it leaves the drivers. An ideal system will have a perfectly flat frequency response and a perfect impulse or step response. As in all real systems, there is a tradeoff between time domain performance and frequency domain performance in these systems. This is complicated by the dual nature of the problem. Part of the system is electrical, the other acoustical, with the different inherent nonlinearities of each.

Rivera-Prosper, Christian

Marcelo, Oscar - Mechanical Engineering,UPRM; Soto, Sujeily - Mechanical Engineering,UPRM; De Jesus, Manny - Chemical Engineering, UPRM; Salcedo, Jose - Chemical Engineering, UPRM; Rivera, Kiara - Chemical Engineering, UPRM

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Engineering

Thermomechanical characterization of chitin-carbon nanotube composites.

Most polymers by themselves possess poor mechanical, thermal and electrical properties compared to other materials such as metallic and ceramic. On the other hand, polymer matrix composites are attractive because of their low cost, high tensile strength, high stiffness, and good corrosion resistance. This work focuses on the study of mechanical behavior of chitin-carbon nanotubes composites. Chitin was the matrix selected because its availability, low cost and biodegradability. The composites were fabricated as films. Of particular interest was the assessment of the composite creep behavior when the material can be plastically deformed and eventually fail working under stresses below it yield strength. Creep behavior, thermal expansion and glass transition temperature were, therefore, analyzed. Preliminary results showed significant improvement in the all those properties of the composite. A model that describes and predicts the creep behavior of this composite is being developed.

Rullan-Semidey, Marivette

Marivette Rullán Semidey - Industrial Engineering, UPR Mayagüez; Nitza M. García - Induastrial Engineering, UPR Mayagüez; Hildelix Soto - Civil Engineering, UPR Mayagüez; O. Marcelo Suárez - General Engineering, UPR Mayagüez

Engineering

Development of Low-Environmental Impact, High Strength Concrete with Fly Ash and Nanosilica

The environmental impact caused by concrete production can be reduced by the development of new fabrication methods of this building material. The utilization of cement in the concrete mixture can be reduced by the incorporation of fly ash. Alas, fly ash also reduces the concrete compressive strength at its early age. To counterbalance such strength loss, additions of nanoparticles of silica have been used. In this research we used statistical and graphical analyses in order to characterize the concrete mixtures behavior. We prepared a control mixture with only cement. Then, the percentage of cement was varied in each mixture design with the addition of fly ash and nanosilica. The design that showed the most similar

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compressive strength to the control mixture was produced with 20% of fly-ash, 77% of cement and 3% of nanoparticles. Hereon, our ultimate goal is to produce a mixture design with higher compressive strength through, at the same time, a cost effective methodology.

Santiago-Collazo, Felix

Silva Araya, Walter - Department of Civil Engineer and Surveying , University of Puerto Rico Mayaguez Campus

Engineering

Computation of Gradually Varied Flow in a Channel System

The first major irrigation project was created during Egypt’s First Dynasty, close to 3100BC, this consist of channels that diverted the flood water .The channel make possible to transport water from a main source, such as a natural river or a reservoir, to the field where the crops are located, making possible the irrigation and growth of the crops that feed our nation. Therefore, it is very important for the agriculturist to know the water level at different section on the irrigation channel. For this, the agriculturist had to know some knowledge on hydrodynamics, therefore is important to develop a practical tool that can be used by any person with basic knowledge on a computer. A simultaneous solution method is proposed and evaluated to determine if the accuracy of the results can compare to the ones obtained by the commercials programs. This algorithm had to be capable to solve of a large number of non-linear equations plus verification of channel regimes and equations describing the flow across hydraulics structures. After performing two case of study on the proposed algorithm and a commercial program, the results demonstrates that the proposed algorithm is more accurate, determining the flow depth, which the commercial program tested. Therefore the simultaneous solution algorithm, accomplish the requirements of being an easy tool to use for the user. Also for a simple irrigation system, the simultaneous solution algorithm is recommended to use instead of the commercial program.

Santiago-Ortiz, Bryan

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Engineering

Exploring statistical learning methodologies towards better movie ratings predictions

It is becoming more and more important to make decisions based on the large amount of data that nowadays it is available. Nonetheless, the analytics methods need to be improved to be able to extract useful information from those large repositories of information in a timely manner. The research community has shown interest in the prediction of movie performance based on user’s reviews, pre-release hype, classification (PG, PG-13, etc), rating prediction from a large number of variables using decision trees, multi-step procedures, Bayesian networks and rule learning [Asad et al. (2012), Reddy et al. (2012), Kabinsingha et al. (2012), Saraee et al. (2004]. These authors have reported more precise and accurate results are needed including a more user friendly implementation of the methods. Therefore our objective for this research project is to search, apply and develop modern data mining methodologies to predict ratings from recent released movies. These models will be used to try to improve the precision and accuracy of the movie rating predictions for any type of movie. To accomplish this task, a series of publicly available dataset will be used to train our model and extract important features. Data from recent released movies (IMDb) will be studied to evaluate the performance of our model. The motivation to solve this research problem lies on providing an analytical method to the movie industry that could allow them to perform better decision making.

Sosa-Rivera, Jesus

Martin, John - Biomedical Engineering, Vanderbilt University; Duvall, Craig - Biomedical Engineering, Vanderbilt University

Engineering

Long-term, Localized Delivery of a Chemotherapeutic

Cancer is the second leading cause of death worldwide. In gastric cancer, most patients are treated by tumor resection in the early progression stages. However, recurrence of cancer at the margin of resection occur in 50% of cases. Systemic treatments like chemotherapy and radiation are the current gold-standard

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treatments but produce systematic toxicities that can severely limit the long term survival of the patient. We hypothesize that prolonged, localized drug delivery at the tumor resection margins will prevent cancer cells proliferation and tumor recurrence. Here, we propose to incorporate a hydrophobic, anti-neoplasmic drug into a hydrophobic, acidically-inert, polymeric film to achieve prolonged drug release and sustained inhibition of cancer cell proliferation in the harsh environment of the stomach. These films were made with poly(thioketal) (PTK) polymers, which are both stable across a wide range of pH values and are specifically degraded by cell-produced reactive oxygen species (ROS). The PTK polymers were synthesized and rigorously characterize. The PTK-Urethane (UR) films were loaded with the strong anti-tumor hydrophobic drug 10-hydroxycamptothecin (HCPT), which has seen limited clinical use due to its poor aqueous solubility but has great potential as a locally delivered. In preliminary studies, PTK-UR films demonstrate gradual, sustained levels of drug release when incubated in an ROS-producing medium, while demonstrating minimal drug release when incubated in saline. Ongoing studies are evaluating the cytotoxic activity of released HCPT and drug release under stomach-mimicking conditions, while futures studies will evaluate the sustained cytotoxic effect of released HCPT both in vitro and in vivo.

Soto-Morales, Bethsymarie

Castilla, David - Chemical Engineering, UPR-MAYAGUEZ; Almodovar, Jorge - Chemical Engineering, UPR-MAYAGUEZ

Engineering

Novel biomaterials for tissue regeneration.

Health problems with partial or complete loss of tissue of an organism can be fought with tissue reconstruction using polymeric biomaterials. Biomedical engineering is the field focused in this reconstruction using specific cells and materials that improve the regeneration. Therefore, the goal of this work is to engineer novel biomaterials to be use in tissue regeneration for clinical applications investigating the use of polysaccharides to be used as polyelectrolyte multilayers. To develop these coatings, the Layer-by-Layer technique is used, consisting of sequence-specific electrostatic interactions between polyelectrolytes representing bilayers over the substrate. Fluorescence microscopy is used to confirm the presence of the coatings. A preliminary test was performed to investigate the effect of chemical crosslinking and choice of polysaccharide on cellular adhesion. It was observed that cells adhere better on more crosslinked films, and preferred the

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chitosan/heparin pair. Lastly, maleimide chemistry was applied to conjugate the adhesive peptide RGD to heparin with the ultimate goal to generate an extracellular matrix material that provides biochemical signals to cells to control cellular behavior. Nuclear Magnetic Resonance Spectroscopy was used to confirm the conjugation of the peptide to heparin. Future research involves measure cellular activities including adhesion, cytotoxicity, differentiation and genetic expression using the biomaterial.

Tirado-Melendez, Aris

Tirado, Aris - Civil Engineering, UPR-Mayaguez; Soto, Hildelix - Civil Engineering, UPR-Mayaguez; Suarez, Oscar Marcelo - General Engineering, UPR-Mayaguez

Engineering

Mechanical Properties of Concrete Containing Fly Ash and Nanosilica

Portland cement is the most expensive material to formulate concrete, and the high-energy consumption upon production is damaging to the environment. A different approach to its fabrication is mandatory to lessen the impact without affecting the concrete’s quality and mechanical properties. For this reason, we have designed a high strength concrete that can be more environmentally friendly. This concrete uses fly ash and SiO2 nanoparticles as a partial replacement to the Portland cement. Other chemical additives such as polycarboxylate superplasticizer were used. Fly ash at its early age reduces the concrete strength but increases it for longer times. The present project proposes that nanostructured silica be added to counteract such resistance loss. Our research hinges on determining the optimal combination of fly ash and nano-silica to reinforce the concrete during its initial stages. The mechanical properties are assessed by compressive, tensile and flexural tests at 7, 28 and 90 days of curing. The results prove that fly ash can be used as a partial replacement for Portland cement and this should not be procurable at the expense of concrete mechanical properties. Nano-silica is used to contribute the material strength at early age.

Vigo-Camargo, Alejandro

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Vigo, Alejandro - Industrial Engineering, University of Puerto Rico - Mayaguez; Carlo, Hector - Industrial Engineering, University of Puerto Rico - Mayaguez

Engineering

Dynamic Cross-dock Door Optimization with More Inbound Trailers than Inbound Doors

This study focuses on the daily inbound and outbound door assignment problem for cross-docks that receive more inbound trailers than the number of available inbound (strip) doors. The objective of the problem is to minimize the makespan (i.e., maximum completion time) to serve all trailers. It is assumed that the flow data and inter-door distances are known, and that all inbound trailers are available when assigned to a door. A simulated annealing-based heuristic that uses alternative heuristics as a sub-routines is proposed and evaluated.

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Environmental Sciences

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Agosto-Torres, Eliacim

Flores-Rodríguez, Yvonne - Biology, University of Puerto Rico–Humacao ; Hernández-Muñíz, Rayza - Biology, University of Puerto Rico–Humacao ; Vicens-López, Coralys - Biology, University of Puerto Rico–Humacao ; Bernardi-Salinas, Ashley - Biology, University of Puerto Rico–Humacao


Captive Breeding and Maintenance of the Puerto Rican Mountain Coquí, Eleutherodactylus portoricensis: an update on a Puerto Rican ex situ conservation project

The Mountain Coquí, Eleutherodactylus portoricensis, is designated Vulnerable by the Department of Natural and Environmental Resources of the Commonwealth of Puerto Rico, Endangered on the IUCN Red List, and recommended for ex situ captive breeding for reintroduction conservation efforts in parts of its historical distribution range. As the first captive breeding program in Puerto Rico for a listed Eleutherodactylus species, here we present most of the laboratory settings; terrarium design and enrichment; watering, lighting, temperature, acoustic ambience, and feeding regimes and procedures; reproductive behavior; filial oophagy; and reproductive events and outcomes, as well as difficulties, problems, and solutions to some of challenges of a captive breeding program. Initially, several individuals were lost because of a recommended substrate (coconut husk) for the terrarium that proved lethal to this species. Once substituted with a new substrate, survival in the colony (24 individuals) has been 100% for more than a year and without the use of medical drugs and related treatment. To date, more than 11 egg clutches have been produced with ~64% hatching success and 27% lost by filial oophagy. Juveniles ~6 months of age are still being raised with the objective of generating an F1 colony in captivity. Lessons from this initiative will be valuable for those interested in starting similar conservation efforts in Puerto Rico.

Allison-Collazo, Gabriel

Cantrell, Sharon - Ciencias Naturales y Tecnologia, Universidad del Turabo

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Microbial diversity in leaf litter decomposition.

It is known that microbial communities play an important role in litter decomposition and nutrient cycling. The Canopy Trimming Experiment being executed at the Luquillo Experimental Forest has been designed to understand the effects and recovery process of a tropical forest ecosystem after the impact of a hurricane. Identifying the changes in microbial community structure in forest floor litter can help us have a better understanding of the factors that influence ecosystem recovery. We studied and compared the microbial community structure in leaf litter samples taken from two different plots of each of the three blocks previously established on the forest floor. Only two time periods were analyzed, pre-treatment and T0, with the purpose of establishing a baseline of each plot for future analysis. The TRFLP technique was used to obtain the profiles of the microbial communities of each sample, three different genetic markers were used, bacterial 16S rDNA region, eukaryotic 18S rDNA region, and fungal ITS region. The diversity between samples was analyzed using clustering algorithms. NMDS and UPGMA cluster analysis using the Bray-Curtis similarity index showed some grouping between litter samples of the same sampling period, indicating there could be a relationship between seasonal changes and microbial diversity. This analysis also showed heterogeneity between samples of the same blocks and an overall heterogeneity between all the samples. This analysis is preliminary to a more extensive project designed to study the effects of canopy openness and debris deposition after the impact of a hurricane.

Baez-Del Valle, Christian

Diaz Camacho, Miguel - Escuela de Asuntos Ambientales, Universidad Metropolitana; Delgado Negron, Nomarys - Escuela de Ciencias y Tecnologia, Universidad del Este; Rodriguez Bonano, Nydia - Escuela de Ciencias y Tecnologia, Universidad del Este


Plasmid DNA Content and Antibiotic Resistance of Enterococcus spp. Isolated from Jobos Bay Estuarine Reserve in Puerto Rico

Recent reports have indicated that enterococci isolated from environmental samples can exhibit multiple antibiotic resistance traits, which are due to the

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presence of plasmids as part of their total genetic content. Therefore, we have assessed the plasmid DNA content and antibiotic resistance patterns of 98 previously identified environmental enterococci isolates. These were isolated from water samples obtained at the Estuarine Bay of Jobos in Puerto Rico and ID via Multiplex PCR. Minimal Inhibitory Concentration Panels (MIC) was performed to each isolate to correlate Plasmid content with antibiotic resistance traits. A classification system for Plasmid from Enterococci and Gram positive bacteria was used for the Multiplex Procedure and amplicons were analyzed. MIC results showed that there is a great variability in antibiotic resistance among the isolates. Several isolates presented multiple plasmids patterns. These were previously identified as Enterococcus faecium and E. casseliflavus. Amplicons at 201 bp to 624 bp were observed and correspond to a possible identification of plasmids pIP501, pCF10 and pIM13. Resistance to antibiotics, especially tetracycline, was observed in about 20% of the E. faecium isolates. E. faecium and E. casseliflavus possess a total DNA content which includes plasmids pIP501, pCF10 and pIM13. This study is in a preliminary stage and is currently in progress. Future experiments will be performed using southern blotting and fluorescent probes to corroborate the plasmid content of the isolates.

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Bruno-Laureano, Yesenia

Mercado-Molina, Alex - Biology, UPR-Rio Piedras; Rivera Irizarry, Fabiola - Biology, UPR-Rio Piedras; Fonseca Miranda, Jaime - Biology, UPR-Rio Piedras


Comparison of physiological activity of Acropora cervicornis and Siderastrea siderea due to thermal stress.

Warming of the ocean water?is one of the major causes of coral bleaching, a phenomenon that is disrupt the?obligate?endosymbiotic?relationships that corals has with dinoflagellates of the genus Symbiodinium. Because it is predicted that sea surface temperature are going to increase 1-3°C in the next 10 years, wich is important to understand how coral species will respond to such changes. It is known that the corals Acropora cervicornis and Siderastrea siderea are species sensible to variations in prevailing water temperature.??However, several studies suggest that Siderastrea siderea can recover faster?than?other corals from thermal-stress, including Acoropora cervicornis. The purpose of this study??is?to determine ?whether the physiology of?these two species?differs with respect to?an increase in water temperature. We conducted controlled laboratory experiments where the corals were exposed to?typical (26.5-27°C)?and elevated temperatures (31.5°C).?We?quantified the densities of the endosymbiotic Symbiodinium spp. as well as physiological parameters?such?as?protein, lipid and chlorophyll concentration to determine whether they change in response to?an?increase in temperature. Results showed?that?colonies of?A.?cervicornis??exposed to an increased temperature did not affect?protein and?chlorophyll concentration. We found that the protein concentration of?S.?siderea?was higher?under thermal-stress?compared?to?corals?under control temperature.?Tests showed that?S.?siderea?had a higher protein concentration than A. cervicornis in both control and thermal-stress treatment. These results?suggest that S. siderea has greater resilience to bleaching-events than?A.?cervicornis. These are preliminary results from what remains quantification of zooxanthella, chlorophyll and lipids.

Calo-Guadalupe, Cristhian

Ayala- Manso Keymari - Universidad del Este; Montero- Parrilla Sirian - Universidad del Este; Maldonado-de Jesus Jorge, - Universidad del Este ; Mercado- Hernández

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Reinaldo - Universidad del Este ; Pabón-Castro Angélica - Universidad del Este ; Malavé-Llamas Karlo - Universidad del Este


‘’Coastal Bacterial Microbiome and Health Risk Assessment of Four Public Tropical Beaches in Puerto Rico’’

Waterborne disease and unsafe public health conditions is a continuous problem amount locals and tourist in the tropic. Tropical islands like Puerto Rico are attractive places for travelers. Warm climate, environmental factors, and anthropogenic impact to beaches, could expose bathers to pathogenic microorganisms, compromising their health. We sample four beaches, 4 water samples per beach and 4 sand samples per beach, totaling 32 samples. Our objective for this assessment is, (a) to determine if the selected sites comply with the quality standards establish by the Environmental Protection Agency (EPA) for fecal indicator bacteria (FIB) and (b) to compare the bacterial concentration in the selected beaches water and sand. Scientific literature has exposed that FIB could be present in beach sand in higher concentrations that in water. Therefore we believe that in cases of beaches with fecal polluted water, people who have contact with the sand, without contacting the water could also be exposed to pathogenic bacteria. Samples were taken and transported at 4oC, to the laboratory. The Membrane Filtration Procedure (MFP) and the EPA 1600 protocol were used to process the samples and the filters were incubated on mFC, mENDO, TSA and m-Enterococcus Agar. The isolates found were exposed to seven antimicrobial agents. Our result shows a percentage of resistance of: 86% for Penicillin, 33% for Streptomycin, 24% for Chloramphenicol, Gentamicin, Kanamycin; and 10% Trimethoprim. Our study reveals that there is a higher concentration of bacteria in the sand and a high prevalence of antibiotic resistant bacteria in our samples.

Cappielo-Rivera, Jimmy B.

ALENO TORRES, RAUL - UIA-PONCE; LOPEZ, ANTHONY - UIA-PONCE; RAMIREZ DOMENECH, JOSE - UIA-PONCE; FERRER, EDMY - UIA-PONCE


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Water analysis and description assessment of Laguna de las Salinas, Ponce, Puerto Rico

The municipality of Ponce is the home of a hyper-saline lagoon, which is about 5 km west of the main port facilities called Puerto Las Americas. During the last ten years, Ponce has been improving his shoreline, in response to the global economic changes. Ponce plans to make a positive economic impact to itself and their boundaries. Are those improvements affecting the pH, turbidity, flora and salinity on this singular water body? Because the singular topography of the area and a highly elevated slope, on the north of the lagoon, all waterways go in the direction and orientation of Las Salinas. Additionally, it receives all the surrounding storm water runoff from the residential areas nearby. It is suspected that pollutants may be deposited in sediments, which may eventually, harm the natural habitat of the zone. The goal of this study is to measure the water quality of the lagoon. The methodology used consists of determinate pH, water turbidity, and water and air temperature. Stations were set at different coordinates and data was measured on site during a four week period. The acquired data was analyzed and summarized in graphs and charts. The data was compared with the National Oceanic and Atmospheric Administration (NOAA) to compare the actual weather condition from 2010 to 2014. According to the study there is evidence suggesting the presence of an isolated mini ecosystem or a mosaic of interconnected mini ecosystems nearby one pre-installed station.

Collazo-Ortiz, Neliann

Dávila, Emmanuel - Biology, UPR-Humacao; Vélez, Silvia M. - Biology, UPR-Humacao


Bioessays of the effect of insect repellent with 98.11% concentration of DEET on populations of dinoflagellate "Gymnodinium instriatum"

It will measure the effect of the main component of the insect repellent Bens 100® Max Tick & Insect in populations of marine phytoplankton. This product has one of the highest concentrations of DEET of 98.11 % in the market. It has been found that this component is harmful to the cells of the human being and the communities of the marine plankton. The island of Puerto Rico, to be a country in the tropical zone,

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it is recurrent use this product in the areas of lagoons, beaches, mangrove and other coastal areas. The DEET toxicity will be measured in the populations "in vitro" of Gymnodinium instriatum (Freudenthal & J. J. Lee) D. W. Coats in concentrations of 10-6, 10-5, 10-4, 10-3 and 10-2 during the periods 0, 1 hour, 24 hours and 48 hours. Identifying the population decreasing by the toxicity of the product will be used the values of fluorometry.

Contreras-Correa, Zully

Cafaro, Matias - Biology, University of Puerto Rico- Mayaguez; Roman, Felix - Chemistry, University of Puerto Rico- Mayaguez


Degradation Capacity of Crude Glycerol by Microorganisms Associated with Fiddler Crab Intestine

As an alternative to the use of fossil fuels, industries have relied on the production of biodiesel. Glycerol, 1,2,3-propanetriol, is a byproduct from biodiesel synthesis. Due to the large residue amounts and low cost of glycerol the idea of using microorganisms to degrade the glycerol and convert it to a renewable fuel source is warranted. For this work, 57 microorganisms previously isolated from the fiddler crab (Uca rapax) intestine were used to determine their capacity to degrade crude glycerol. The microorganisms were inoculated in three different synthetic media: negative control without a carbon source, positive control with dextrose and for the experimental, with 5% glycerol. They were incubated at 28ºC for 4-7 days. Eight microorganisms were capable of growing using crude glycerol as a primary carbon source; but only four of them were able to alter the medium color meaning that they produce secondary metabolites. The strains that produced secondary metabolites were identified as Streptomyces sp., Bacillus sp., and Enterobacter sp. Also, these strains showed faster growth in comparison to the others.

Correa-Pascuas, Nicolas

Correa, Nicolas - Biology, University of Puerto Rico Rio Piedras; James Aaron Hogan - Environmental Sciences, University of Puerto Rico Rio Piedras

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Comparing multivariate statistical methods: PC-ORD vs R

The use of computer software has become an indispensable tool for analyzing, interpreting and evaluating ecological data. With the increase in popularity of multivariate statistical approaches used to understand the complex patterns and relationships among species in diverse ecological communities, many software programs have been developed. One of the most widely-used is PC-ORD, which enables users to produce publication-quality analyses with minimal effort and little computer-science programming knowledge at a minimal cost (about $250 per license). On the other hand, newer open sources statistical environments capable of performing the same high level statistical analysis have been created for free. The R statistical computing program is a commonly used tool among scientist, mathematicians, and academics, it offers many tools available at PC-ORD, but requires more statistical knowledge by the user and computer programming skills. We compare the capabilities and analysis approaches of the two statistical software systems, PC-ORD and R, using long-term (20 years) data from the Luquillo Forest Dynamics Plot (LFPD) with the motivation to uncover nuances in two particular analyses: Multiple Response Permutation Procedures (MRPP) and Indicator Species Analysis (ISA). PC-ORD will be contrasted with three different R packages of similar statistical power: labdsv, vegan, and indicspecies. Differences exist between R statistical packages, themselves, and between methods employed in PC-OR, we will explore how the results of the two different platforms differ both in method employment and in statistical outputs.

Cortes-Hernandez, Ashley

Ramos Cruz, Melissa - Natural Sciences, University of Puerto Rico- Aguadilla; Ferrer Colon, Taishalyn - Natural Sciences, University of Puerto Rico- Aguadilla; Roman Alvarez, Priscilla - Natural Sciences, University of Puerto Rico- Aguadilla


Spatial and temporal zonation of organisms in a Rocky Shore as a means of assessing biodiversity in “Surfer’s Beach” Aguadilla. P.R.

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Rocky intertidal shores are exposed to wave action, sunlight, and other biophysical factors, thus, organisms that live in these ecosystems are under varying environmental conditions and stress. Recently organisms found in rocky shores have been studied as bioindicators of water quality and climate change. Among the varying species we can find on rocky intertidal shores are the gastropods. The objective of this study was to determine the temporal and spatial distribution of gastropods Tectarius muricatus and Nerita sp. in Surfer’s Beach, Aguadilla, P.R. therefore contributing to databases for large-scale diversity comparison of intertidal shores. We used the quadrat and transect method to collect our data and analyzed density, frequency, and dispersion of these gastropods on two different sites on two different dates, using Microsoft Excel software. It was found that Tectarius had an average density of 66.5 ind/m2 in the horizontal zone and 37.0 ind/m2 in the vertical zone, with a frequency of 85.7% in the vertical zone and 0.8% in the horizontal zone. Nerita had an average density of 0.309 ind/m2 in the horizontal zone and 5.71 ind/m2 in the vertical zone, with a frequency of 57.0% in the vertical zone and 0.9% in the horizontal zone. We found an aggregated distribution pattern for Tectarius, and a random distribution pattern for Nerita. Significant differences, P < 0.05, were found for frequencies and distribution between both zones for both species. We conclude that Tectarius was more abundant farther from the shore and Nerita sp. closest to the shore.

Cruz-Ruiz, Leonellis


Determinación de la distribucion de frutos a través de la infructescencia en Campylocentrum fasciola (Lindley) Cogniaux

La producción de frutos a lo largo de la infructescencia puede verse afectado por la limitación de recursos, comportamiento de los polinizadores y la arquitectura anatómica de la planta. Si ninguno de los factores mencionados influencia la produccion de frutos, la frecuencia de frutos a lo largo frutos de la infructescencia debe ser igual. Recopilamos los datos de la posicion y la distribucion de frutos de 200 infructescencias en la orquidea epifita Campylocentrum fasciola, una especie sin hoja. Se encontró que las posiciones en la infructescencia con mayor porcentaje de frutos se encuentran entre las primeras diez posiciones con un promedio de 60% de frutos. Este resultado demuestra que existe un factor o varios factores anteriormente mencionados que limitan la producción de frutos a través de la infructescencia.

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Dávila-Santiago, Emmanuel

Sastre, Miguel P. - Coastal Marine Biology, UPR-Humacao; Vélez, Sylvia M. - Coastal Marine Biology, UPR-Humacao


BIOESSAYS OF THE EFFECT OF COMMERCIAL GRADE 5% DEET MOSQUITO REPELLENT ON “IN VITRO” POPULATIONS OF THE DINOFLAGELLATE GYMNODINIUM INSTRIATUM

In Puerto Rico’s coastal areas, including in bioluminescent bays, it is very common to use mosquito repellents containing DEET. This molecule has been reported to be very toxic to different kinds of human cells. Therefore, we suspect DEET could have adverse effects on marine planktonic populations. The objective of this work is to test the effects of DEET on “in-vitro” populations of the dinoflagellate Gymnodinium instriatum (Freudenthal & J.J.Lee) D.W. Coats. Bioassays were performed on G. instriatum “in-vitro” populations with varying concentrations of commercial grade 5% DEET (Off! family care insect repellent III) dissolved in the culture medium, in order to observe the mortality rate of the populations. Population densities were estimated by fluorometry. Fluorometer measurements were validated by using visual counts. Results show that a concentration of 10-3 is near the amount that affects more than half of the individuals in the populations. These results suggest that DEET could be a real threat to natural marine planktonic populations.

De La Rosa-Acosta, Melanie

Daly, Rebecca - Microbiology, The Ohio State University; Solden, Lindsey - Microbiology, The Ohio State University; Angle, Jordan - Microbiology, The Ohio State University; McVeety, Raymond - Microbiology, The Ohio State University; Daniels, Charles - Microbiology, The Ohio State University; Reeve, John - Microbiology, The Ohio State University

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Assessment of the Microbial Diversity of Lake Retba

Hypersaline environments contain a wide diversity of microorganisms that remain understudied. We explored Lake Retba, or “Lac rose” in local French, which has rose-colored water due to the pigmented halophilic archaea. This Lake is located in Senegal, Africa (14°49’30” N 17°14’30” W) near Dakar and 100 m from the Atlantic Ocean. The water chemistry has an average of 40% of salinity (~11.4 x that of ocean water). We used both cultivation and molecular approaches to characterize the planktonic microbial community in the lake. A defined hypersaline medium was used in aerobic enrichments amended with succinate as a carbon and energy source. To analyze the anaerobic microbial community, a complex hypersaline medium was amended with yeast, peptone and dextrose (YPD) and incubated under a nitrogen headspace. Six aerobic cultured colonies were isolated and by 16S rRNA gene sequencing were confirmed as two archaeal genera: Haloterrigena spp. and Haloferax spp. Microscopically the Haloterrigena appeared as non-motile cocci (1.5-2.0 µm), while Haloferax were motile, pleomorphic cells ranging from small rods to cocci (1.0-1.5 µm). We are currently using 16S rRNA gene sequencing from filtered Lake Retba water to characterize the in situ microbial community, and assess the environmental relevance of our cultivated strains. This research opens the door for deeper analysis with insight on the microbial diversity and interactions in saline environments.

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Diaz-Rivera, Jazmin M.

Cáceres-Charneco, Rita I. - Biology, UPR- Rio PIedras; Ortiz-Zayas, Jorge R. - Environmental Sciences


Soil salinity dynamics in a temporary coastal pond

Mineral salts are a natural component of coastal wetland ecosystems. Wetland plants and animals can evolve adaptations to survive under differing salinity concentrations depending on the level of exposure. Salts are water-soluble and can enter coastal wetlands through precipitation, sea spray and soil surface runoff. Salts can also enter coastal wetlands by exudation from plants like mangroves. We focused our salinity concentration study in the Tamarindo pond, a coastal ephemeral pond in the Guanica Dry Forest. This pond is the only natural breeding site of the Puerto Rican Crested Toad (Peltophryne lemur), internationally recognized as an endangered species. Tamarindo pond is mostly surrounded by Avicennia germinans (black mangrove) and Rhizophora mangle (red mangrove). We conducted three preliminary studies to explore salinity concentration in the pond. First, we constructed a mangrove tree model in order to measure salt deposition by sea spray. Second, we compared the salt concentration on leaf surfaces of two mangrove species. Third, we measured soil salinity by collecting surface soil samples from the dry pond bottom surface. Our initial findings suggest that our proposed methods can detect salt deposition on the mangrove tree model, that there is different salt accumulation on tree leaves between two mangrove species; and that soil salinity can be easily measured using a soil-water dilution. This preliminary study proposes a conceptual model of salinity cycling for the Tamarindo pond where sea spray, plant salt uptake and exudation and dilution by rain water affects the salinity of the pond water causing a stress to freshwater species like the Puertorican Crested toad. The model can can also be applied to nearby coastal ephemeral ponds as well.

Duquesne-Maldonado, Yanice

Vanessa Santiago - Biology Department, UPR-Rio Piedras; Isamarie Rivera - Biology Department, UPR-Rio Piedras; Claudia Ruiz - Environmental Science, UPR-Rio Piedras; Alexander Rodriguez - Environmental Science, UPR-Rio Piedras;

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Xochitl Perez - Environmental Science, UPR-Rio Piedras; Loretta Roberson - Environmental Science, UPR-Rio Piedras


Annual variation in the presence and distribution of phthalates in the San Juan Bay estuary

Phthalates are a group of chemicals used to soften and increase the flexibility of plastic and vinyl, and are used in hundreds of consumer products. They are not chemically bound to products and are, therefore, released into the environment where they may enter the human body by ingestion, inhalation, or dermal absorption. This study is focused on the presence, distribution, and concentration of plasticizers, particularly phthalates, in the San Juan Bay Estuary of Puerto Rico. This estuarine ecosystem is enclosed in the San Juan-Carolina Metropolitan area. A comparison of pollutants for the years 2012-2014 was performed at a total of 16 sites. We analyzed water samples by solid-phase extraction coupled with gas Chromatography/mass spectrometry, and then compared them between years and between sites. Our results have shown that although plasticizers have varied over the years, the compounds have generally remained persistent in the estuary. Dibutyl phthalate is one of the compounds that have been consistently recorded over the years and repeatedly in most sampling sites, indicating that this contaminant may be a threat to the ecosystem. The population density is expected to continue increasing each year and therefore the number of concentration of contaminants found in aquatic environments due to human activities will also likely increase.

Estrada-Rosado, Eduardo

Estrada Rosado, Eduardo - Universidad Metropolitana; Santiago, Iliansherry - Universidad Metropolitana; Moreno, Yarianne - Universidad Metropolitana; López, José - Univerisdad Metropolitana; Infante, Gabriel - Universidad Metropolitana


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TRACES OF CHEMICAL COMPOUNDS IN CARRAIZO RESERVOIR AND SERGIO CUEVAS WATER TREATMENT PLANT IN PUERTO RICO

Using the UV-Vis spectroscopic (spectrophotometer HACH) technique, the ions Nitrate and Nitrite concentrations on water samples from Carraizo reservoir and Sergio Cuevas Water Treatment Plant were analyzed. Also, certain metals concentrations such as: Al, Ca, Cu, Fe, K, Mg, Na, and Pb will be determined using Atomic Absorption (AA) and Induced Couple Plasma Emission Spectroscopy (ICP) techniques and the US Environmental Protection Agency (EPA) established methodology. Previews results of this analyses show that the Ions Nitrate and Nitrite were lower in Sergio Cueva than in Carraizo. Additionally, the concentrations of most of the analyzed metals were lower than the standards establishing by the regulating agencies. However, the concentrations of Al, Fe and Pb metals were somehow higher than the standards established by Puerto Rico regulating agencies. The concentrations of ions Nitrate and Nitrite and some metals will be compared between Carraizo reservoir and Sergio Cuevas Water Treatment Plant and discussed during this presentation. The discussion will include the implications that the above results may have in the pollution control of treated and non-treated surface waters in Puerto Rico. The collaboration of the Puerto Rico Water and Sewer Authority (AAA), especially Sergio Cuevas Treatment Plant staff and the UPR Molecular Studies Center is gratefully Acknowledged.

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Fernandez-Negron, Luis


Dose-response bioassay for the toxic potential of V4+ and V5+ in Artemia salina hatching rates

A dose–response relationship describes the change in effect on an organism caused by differing levels of exposure (or doses) to a stressor (usually a chemical) after a certain exposure time. The purpose of this study is to determine the levels of toxicity (dose) of two vanadium species (V4+, V5+) using the hatching rate of Artemia spp. as the dependent variable (response). Different concentrations of vanadium at a same exposition time will be used. Artemia cysts are re-hydrated and decapsulated prior to incubation for 15-20 hours using the equivalent of 1,000-lux incandescent light intensity at 25ºC. Cysts are separated from shells once larvae have hatched and counted using the Lugol Solution method. The lethal and sub-lethal doses are going to be established. Results will be presented in the conference.

Figueroa-Rios, Lysmarie

Poovaiah, Charleson - Biology, Syracuse University; Xiao, Yao - Biology, Syracuse University; Northern, Lilibeth - Biology, Syracuse University; Coleman, Heather - Biology, Syracuse University


Screening of alcohol-inducible transgenic poplar trees and quantification of transgene expression.

In an effort to reduce the cost of enzymes used in biofuel production different approaches have been taken to obtain high levels of protein expression. The INPACT -In Plant ACTivation- system provides an alternative system to produce high levels of recombinant proteins in planta. INPACT is tightly controlled by an alcohol inducible component the AlcA:AlcRep gene switch which when combined

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with a split gene construct provides negligible expression before induction. In this study we tested the efficiency of the alcohol-inducible component of the INPACT system in poplar trees upon induction with ethanol. High-level expression of AlcA/AlcRep were obtained after induction with ethanol whereas negligible expression levels for AlcA:AlcRep gene switch were obtained before ethanol induction. However more optimization is required. Future work is directed to reproduce ethanol induction of Rep proteins in green house grown poplar trees and to quantify AlcA:AlcRep gene switch via more accurate techniques such as qPCR.

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Gil-Acevedo, Jennifer

Colón, Abelardo - Department of Environmental Science, University of Puerto Rico Rio Piedras Campus; Arroyo ,Axel - Department of Chemistry, University of Puerto Rico Rio Piedras Campus; Avalos, Bárbara - Department of Biology, University of Puerto Rico Rio Piedras Campus; Avalos, Javier - Department of Physics, University of Puerto Rico Bayamón Campus; Morell, Gerardo - Department of Physics, University of Puerto Rico Rio Piedras Campus; Weiner, Brad - Department of Chemistry, University of Puerto Rico Rio Piedras Campus


Nanodiamond Powder as Reusable Nontoxic Water Disinfection Material

Detonation Nanodiamond or ultra-disperse Nanodiamond (UDD) is an interesting carbon allotrope since it has a small particle size (4-5 nm), facile surface functionalization and great bio compatibility properties that can be used for many biomedical applications, such as drug delivery, surface coating and anti-bacterial/anti-viral treatments. We have carried out studies of UDD as a bactericidal agent on water treatment plants. Current US water treatment plants use chlorine to disinfect surface water, but improper management of this hazardous gas can cause lethal effects on water plant workers and water users. Moreover, disinfectant by products (DBP’s) produced by chlorine disinfection process have raised health concerns because they can cause cancer to the population that drinks water or inhale vapor. We mixed UDD powder with river water from urban, rural and urban/rural watersheds to determine the effectiveness of UDD as a nontoxic reusable water treatment agent. Qualitative (UV and normal imaging) and quantitative data (statistical analysis) were done and the results showed strong bactericidal properties of UDD on fecal E. coli bacteria present in river water from 3 different watersheds. These promising results demonstrate that UDD can be used to disinfect fecal bacteria found in surface water bringing a nontoxic new disinfection material for water treatment plants.

Gomez-Marie, Kiara

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Aquatic Hyphomycetes Present in Foam from the River Caguítas in Caguas, Puerto Rico

Kiara I. Gomez Marie* and Chad Lozada-Troche Aquatica Hyphomycetes present in foam samples from Caguitas River, Caguas, Puerto Rico Aquatic hyphomycetes are microfungi found in foam samples, leaves and immersed plant material in fresh water streams. They are the primary degraders of plant organic matter that falls into the water. This study is centered on determining the biodiversity, frequency and abundance of this microfungi on foam samples from Caguitas River in Caguas, Puerto Rico. Samples were collected from September to November 2014. A total of 35 fungal species previously reported and 47 unknown species were identified through microscopic observation. The most common species were Dactylella submersa, Campylospora filicladia, Helicomyces colligatus, Helicomyces torquatus and Clavatospora tentacula. Species variation in frequency and abundance was observed when all the samples were compared. This variation may be due to physical and chemical changes such as water temperature, pH and the amount of substrate among other factors. Att. Dr. Chad Lozada

Gonzalez-Berrios, Jessica

Pérez-Jiménez, José R. - School of Natural Sciences and Technology, Universidad del Turabo


Antimicrobial activity from the San Juan Bay Estuary

Bacteria have developed resistance to antibiotics, which has become a critical health issue impacting the world. Bioprospecting antimicrobial potential among marine microorganism could provide alternative. It has been shown that marine bacteria contain different types of compounds that help health. Our objective is to characterize bacteria with antimicrobial potential from marine ecosytems. Water samples were collected along the San Juan Bay estuary. One mililiter of each samples was cultivated in Tryptic Soy Agar and Actinomyces Isolation Agar by spread plate for a week at room temperature. Media was prepared with site water. Growth was examined daily for evolution of inhibition zones and isolation of participant bacteria. Fifty colonies were isolated and purified. Most of these colonies expressed a variety of pigmentation of their phenotype. Bacterial isolates have

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been partially characterized based on Gram stain and catalase production. Antimicrobial activity was tested in concurrent cultures of isolates with reference strains in agar plates. Most of the isolates were Gram-negative rods, and positive for catalase production. Among them, eight strains demonstrated antimicrobial effect against Acinetobacter baylyi, Bacillus subtilis, Enterobacter aerogenes, Escherichia coli, and Staphylococcus epedermis. We are in the process of completing characterization of isolates by 16 rDNA sequencing.

Hernandez-Muniz, Rayza

Agosto-Torres, Eliacim - Biology, University of Puerto Rico–Humacao ; Vicens-López, Coralys - Biology, University of Puerto Rico–Humacao ; Bernardi-Salinas, Ashley - Biology, University of Puerto Rico–Humacao ; Ríos-López, Neftali - Biology, University of Puerto Rico–Humacao


Population Ecology of the Puerto Rican Melodious Coquí, Eleutherodactylus wightmanae, from a mountain forest at the Sierra de Cayey

The Melodious Coquí, Eleutherodactylus wightmanae, is a small frog (mean SVL = 20.2 mm) common in high elevation forests and inhabits forest leaf litter. The species is listed as endangered on the IUCN Red List, but the Department of Natural and Environmental Resources of the Commonwealth of Puerto Rico does not list the species or consider it to be under any imminent threat. However, little is known of the species’ population ecology, which may explain in large part discrepancies, both at local and international levels, on its current population status. In this study, we provide most of the information currently known on the population ecology of the Melodious Coquí from a high elevation forest at the Sierra de Cayey. In this forest, the species is the second most abundant in the Eleutherodactylus assemblage, reaching >500 individuals ha-1 on average (mostly adults and large body-sized individuals). Monthly census conducted between December 2013 and November 2014 revealed a population variation typical of other Eleutherodactylus from Puerto Rico: population density increases with an increase in ambient temperature and rainfall during months between May and November, and decreases between December and April, months of lower temperature and less rainfall. The number of egg clutches produced follows a similar pattern: more egg clutches are frequently found during months of higher temperature and rainfall. We also document the frequency of individuals being found on various vegetation

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categories and substrates in the forest as an attempt for characterize the species’ microhabitat use.

López-Carrasquillo, Jonathan

José R. Pérez-Jiménez - School of Natural Sciences and Technology, Universidad del Turabo; Yomarie Bernier-Casillas - School of Natural Sciences and Technology, Universidad del Turabo


Diversity of Sulfate-Reducing Bacteria along the Martin Pena channel

Sulfate reducing bacteria, SRB, have played an important role in our ecosystem. These anaerobic bacteria are responsible for the biogeochemical cycle of elemental sulfur as sulfate is used as the final electron acceptor. Many SRB have been demonstrated to degrade organic pollutants under seawater influence. The dissimilatory sulfite reductase genes, dsrAB, have been used as biomarker to characterize the SRB because is the ultimate catalyst of sulfate respiration. Chronically, Martin Pena channel, connecting San Jose Lagoon to San Juan Bay, has been exposed to a accumulation of diverse pollutants threatening environmental and public health. Our objective is to determine the diversity of sulfate reducing bacteria along the Martin Pena channel. Soil samples were collected in nine sites along riverbanks of the Martin Pena channel. Total DNA was extracted for amplification of dsrAB genes. Amplicons digested with NdeII were analyzed by Terminal Restriction Fragment Length Polymorphism, TRFLP. Initially, the dsrAB genes were amplified for two terminal sites of the nine. TRFLP profiles indicate diverse phylotypes dominated by many common phylotypes which relative abundance contrasted among sites. Diverse sulfate reducing bacteria were detected in the Martin Pena channel. Differences between profiles can be influenced by local physicochemical conditions under study, including prevailing pollutants. In order to provide additional insights, metagenomic and soil analyses are in progress.

Lopez-Gonzalez, Diorella M.

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Gonzalez, Sherkarina - Sciences and Technology, Universidad del Este; Mendez-Sotomayor, Elvin - Sciences and Technology, Universidad del Este; Nuñez-Acosta, Jennifer - Sciences and Technology, Universidad del Este; De la Cruz- Montalvo, Lucia - Sciences and Technology, Universidad del Este; Pabon-Castro, Angelica - Sciences and Technology, Universidad del Este; Perez-Velez, Mariel E. - Sciences and Technology, Universidad del Este


Detection of Enteric Bacteria in Ready to Eat Produce

The recent widespread consumption of ready to eat fresh foods (produce), has resulted in recurrent outbreaks with foodborne agents in the United States, mostly enteropathogenic strains of Escherichia coli O157:H7 and Salmonella spp. The level of exposure to foodborne pathogens in Puerto Rico is slightly known, specially through consumption of produce. The main objective of this study is to analyze the microbial quality of leafy green vegetables and characterize the bacterial isolates based on their biochemical profile. Our hypothesis is that most of the produce are contaminated with enteric pathogens. Lettuce, cilantro and coriander samples were collected and processed using the FDA Bacteriological Analytical Manual (BAM) and Semedo-Lemsaddek et al. method (2009). Enriched samples were diluted and plated in TSA and in corresponding selective media, for each bacterial group. All processed samples dilutions resulted too number to count (>300 colonies/plate) in all selective media for presumptive Escherichia coli and Salmonella. On the other hand, an average of 104 CFU/g of presumptive enterococci was obtained from cilantro, 106 CFU/g from lettuce and 109 CFU/g from coriander. Based on the confirmation tests and rapid identification panels (API 20E for enterobacteria and API strep for enterococci), isolates were mostly identified as Enterobacter spp., Escherichia coli, Enterococcus faecalis and Enterococcus faecium. Salmonella spp. was not confirmed among the isolates. These data suggest that there is contamination with enteric bacteria in ready to eat foods in Puerto Rico. Further sampling and experiments are required to confirm the microbial quality of produce in Puerto Rico.

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Lopez-Pena, Nicole


Analysis of Heavy Metals in Fish at the Natural Reserve “La Parguera”, Puerto Rico

The natural reserve “La Parguera” located in the island of Puerto Rico, is one of the mayor touristic attraction due to the fact that this region is home to one of the seven bio-luminescent bays in the world. This reserve is supervised by the Department of Natural and Environmental Resources of Puerto Rico (DRNA) tasked with protecting and maintaining a balanced ecosystem. In this study was determined the concentration of Cd, Pb, and As in the edible part of the fish inhabiting at this reserve. Exposure to heavy metals through fish consumption represent a health risk, especially for high-fish-consumption populations such as the inhabitants that live near this region. Samples were taken from three different areas within the reserve. In order to determine the amount heavy metals present in each fish they were subjected to a wet digestion with nitric acid and sulfuric acid the resulting solutions were then analyzed by flame atomic absorption spectroscopy. Preliminary results, showed a content of heavy metals in all the samples. Ultimately, future projects will be aimed at studying the heavy metals content in the entire ecosystem.

Maldonado-Velez, Gabriel

Medina-Pérez Eulalia - Chemistry; Osorio Cantillo Celia - Chemistry; Ramírez-Domenech José I. - Biology; Ferrer-Torres Edmy - Chemistry


Functionalization of Indole-3-Acetic Acid with gold nanoparticles synthesized through a double reduction reaction using leaflets’ extracts of Leucaena leucocephala (Lam.) de Witt.

The chemical profile of Leucaena leucocephala, a worldwide distributed mimosoid legume, is suitable to explore its role in the synthesis of nanoparticles and their

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functionalization with organic molecules such as plant hormones. Functionalization of plant hormones with nanoparticles is an innovative strategy to enhance the impact of nanotechnology in environmental stress situations and biotechnology. In this work gold nanoparticles were synthesized making a double reduction using leaflets’ extracts of L. leucocephala and citrate. The obtained nanoparticles were characterized, using a UV spectroscopy and a Dynamic light scattering to estimate the nanoparticle size. Results of green gold nanoparticles functionalized with hormone Indole-3-Acetic Acid shows a red shift displacement at 545-572 nm, indicating functionalization. The nanoparticle remained stable for four weeks and the size ranged between 65-80 nm. These results indicate the effectiveness of the Leucaena leaflets’ extracts in the synthesis and functionalization of the gold nanoparticles.

Martinez-Cortes, Aranxa M.

Martínez Cortés, Aranxa M. - Department of Environmental Science, University of Puerto Rico, Río Piedras Campus


A study of equivalent black carbon concentrations over Puerto Rico using a light transmission method

Black carbon (BC) is the most strongly light-absorbing component of particulate matter (PM), and is formed by the incomplete combustion of fossil fuels, biofuels, and biomass. BC particles absorb visible light at all wavelengths. This absorption leads to additions of solar energy to the atmosphere, and therefore a reduction at the Earth’s surface referred to as surface dimming. It also affects cloud processes, visibility, and the melting of snow and ice cover. Being in the fine fraction of the PM (< 2.5 ?m) BC can also have adverse health effects and its lifetime in the atmosphere is in the order of 7 to 10 days; therefore, it is known as a short-lived climate pollutant. For the Caribbean, specifically Puerto Rico, the lack of BC measurements leads to uncertainties with respect to the impact this species could have for the region. Using data generated at the atmospheric observatory in Cape San Juan, Puerto Rico, we seek to gain a better understanding of the variations and trends in equivalent BC concentrations as measured with the aethalometer over the last 10 years and how these concentrations vary with season and with the origin of the air masses. With this study we hope to provide opportunities for future BC mitigation strategies and various other studies regarding BC in the region.

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Martinez-Lopez, Aglee

Jacqueline Mejia - Department of Environmental Chemistry and Technology Program ; Matthew Ginder-Vogel, PhD, - Department of Environmental Chemistry and Technology Program


Metastable Fe-mineral formation via NO3- dependent Fe(II) oxidation

Iron (Fe) forms different minerals that are diverse in color, structure and elemental composition. Fe is found in two main oxidation states, Fe2+ and Fe3+. Fe2+ can be found in the aqueous phase, while both Fe2+ and Fe3+ form solid phase minerals that undergo dissolution/precipitation and redox transformations. Iron reduction and abiotic iron oxidation with O2 are processes that are well understood. Nitrate (NO3-) can also drive the oxidation of Fe in the presence of a carbon source and bacteria. However, it remains unknown whether this reaction is enzymatically or chemically driven. Scientists are trying to understand how nitrate-dependent Fe(II)-oxidation occurs and there are some proposed mechanisms that describe the process. In this study our goal is to study nitrate-dependent Fe(II)-oxidation by simulating the conditions of a natural environment. Our experimental design consists of having reactors with different sources of natural inoculum, iron and nitrogen. We specifically induced Fe(II) oxidation with nitrate and nitrite. The results from this preliminary study state that NO3- does not oxidize aqueous Fe(II) without the presence of a carbon source, and thus no minerals are formed. The reactors containing nitrite (NO2-) undergo a chemical reaction where NO2- is reduced and Fe(II) is oxidized and forms Fe(III) and Fe(II) containing minerals.

Morales-Soto, Wilmarie

Arce, Javier - DEpartment of Biology, UPR Cayey


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Comparing the effectiveness of land classification using R randomForrest and eCognition for the use of predicting water quality

Puerto Rico currently has 299 Non-PRASA systems, which account for 59% of the total public water systems on the island. Non-PRASA systems are those that are not serviced by the Puerto Rico Aqueduct and Sewer Authority (PRASA). The majority of these systems are located on the rural area of the island, which are areas that are characterized as areas with increased poverty. This can be potentially hazardous to these communities since poor water quality can result in the proliferation of and array of diseases and toxic compounds. Due to their lack of resources they are often unable to administer the proper treatments and testings’ for these systems. With the increasing importance and awareness of water quality of these systems, a modelling system is needed for the monitoring and predicting of water pollution. The parameters of the model are would include data of water quality together with land cover types. The biggest setback in the development of this model has been coming up with an accurate classification of land cover types. For this reason this study examines methodology that can significantly improve land cover classification. For our study areas we used our previously established watersheds- 92 Non-PRASA systems- and we classified the area using different methods: R-randomForrest and eCognition supervised classification. Both classification were later evaluated for accuracy using kappa statistics. Both methods resulted with an accuracy over 75 percent. However, our results suggest that the R-randomForrest classification had a 2 percent more accurate classification than eCognition.

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Muriel-Mundo, Chris A

Vazquez Rivera Emmanuel - Molecular & Environmental Toxicology, Madison- Wisconsin; Bradfield Christopher - Molecular & Environmental Toxicology, Madison- Wisconsin


Yeast as a Biosensor of Chlorinated Hydrocarbon

Halogenated aromatic hydrocarbons (HAH’s) are an enormous group of compounds widely distributed and highly resistant to chemical and biological degradation. These compounds are extremely toxic and with an extraordinary bioaccumulation and biomagnification potential. These properties make compounds like 2,3,7,8 tetrachlorodibenzo [p] dioxin (TCDD) a member of the HAH’s, have a significant impact on human, animal and environmental health. Current methods used for detection and quantifiaty of HAH’s and it’s congeners are time consuming and not cost-effective. For this reason, the development of new methodologies for inexpensive and rapid detection and estimation of toxicological parameters of pure compounds and complex mixtures, such like environmental samples. In an effort to contribute with this effort we are studying the toxicological parameters of a variety of compounds using an approach developed in our lab. After exposing the transformants to different concentration of compounds ?NF and ?NF showed to have AHR activity in our yeast model system with a EC50 of 2.3 x 10?7 M of ?NF and 6.6 x 10?8 M for ?NF.

Navedo-Gonzalez, Luis

Navedo, Luis - Sciences and Technology, Universidad del Este; Mendez, Loyda - Sciences and Technology, Universidad del Este; Rodriguez-Bonano, Nydia - Sciences and Technology, Universidad del Este; Diaz-Camacho, Miguel - Sciences and Technology, Universidad del Este


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Metal Resistance In Environmental Enteroccocus faecalis Strains Isolated From Irrigation Water

Enterococcus spp. are gram-positive commensal bacteria found in the GI tract of humans and animals. Resistance to antibiotics and heavy metals has been reported in environmental strains of Enterococcus spp. Their presence in the environment is of public health concern since Enterococci are a common cause of community-acquired and foodborne diseases, causing approximately 800,000 infections per year in USA. The purpose of this study is to determine metal resistance patterns in environmental strains of Enterococcus faecalis isolated from irrigation water. E. faecalis were isolated from water samples obtained in a farm near the Jobos Bay Estuary, which uses well water for irrigation. The minimum inhibitory concentration for lead, iron, and copper was determined using the micro-broth dilution technique. Briefly, enterococci were incubated with increasing concentrations (0.03-1.6 mg/mL) of the metals dissolved in brain heart infusion broth supplemented with 0.5% nalixidic acid. The absorbance (595nm) was measured after 24 and 48 hrs of incubation. Preliminary results exhibited differences in metal resistance patterns among E. faecalis strains, with some strains showing high resistance to lead and copper. Meanwhile, our control strain (ATCC 29212) was sensitive to all the tested metals. Other studies have found that antibiotic and heavy metals resistance are highly correlated in Enteroccocus spp. Therefore, these preliminary results are important to public health since in many instances foodborne diseases are associated with contaminated water used for irrigation.

Olmeda-Viera, Natalia

Tremont, Rolando - Chemistry, University of Puerto Rico-Humacao


Applied Electrochemistry for the Analysis of Heavy Metals on Vieques' Soils

In this study, the concentration of heavy metals {Pb, Hg, Cd, Zn and Cu} in the island of Vieques was scrutinized through electrochemical method. The purpose of this work was to prove the effectiveness of this method for the direct extraction of the heavy metals in the land adjacent to the SWMU 6, of the west side of the island, thus finding a method for the complete extraction from the area. The method consisted in creating a template method to apply the electrodes deposition of these

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metals, directly from the studied soil. After the extraction of the platinum (Pt) electrons, a digestion of the nitric acid 50% v/v was conducted, to dissolve the heavy metals that were deposited on the electrodes. Then the evicting electrochemical technique, to corroborate the presence of these metals in the soil, making a sweep to more positive potentials. The evicting current of each metal is proportional to the concentration of the solution of the study. In all of the soil samples studied mercury (Hg) was found along with an unknown substance. The greater the depth of the sample (B2 and C2), the higher is the amount of Hg found. Hence, it may be concluded that the electrochemical method of extraction may be effective for the extraction and analysis of heavy metals in the soil of Vieques.

Padilla-Del Valle, Ricky


Unraveling Antibiotic Resistance Genes of Microbial Communities Using Metagenomics

Antibiotic Resistance (AR) infections has placed the world in a new age against potential microbial pathogens: the Post-Antibiotic Era. While classic microbiology studied those microorganisms using culture-dependent approaches, functional metagenomic analysis shows that the AR genes present in microbial pathogens at hospitals was first originated in microbial communities of the world’s environments and that more of the 99% of them cannot be cultivable. The focus of our research was to generate metagenomic libraries (ML) from two different types of conditions: from a pristine environment and an anthropogenic impacted ecosystem (HAIE). Then, explore for AR genes against ampicillin. Two ML from compost, a vegetable waste and a human biosolid, were generated (representing the HAIE) and two ML from soils of Isla de Mona, PR were also generated (representing the pristine environment). The high molecular weight (40kbp) DNA of each one was end repaired, electro eluted, and ligated into the fosmid vector pCCFOS1, then, transduced to Escherichia coli Epi300-T1R using T1 bacteriophage. The Minimal Inhibitory Concentration (MIC) of ampicillin (15µg/mL) was determined. The AR clones from the libraries were isolated by selection on culture media supplemented with 1X-10X MIC ampicillin. While many clones in the ML of composts showed AR to 1X-10X MIC of ampicillin, no AR to ampicillin was detected in the clones from the pristine environment. These results represents that anthropogenic impacted environments are potential reservoirs of ?-lactams AR in contrast to the pristine environment. Now, work is in process to detect the AR gene(s) responsible for the activity.

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Pagan-Cruz, Alejandra

Fernandez-Alos, Victor - Roman-Velazquez, Felix


Synthesis of magnetite for the removal of organic contaminants and calculation of the Point of zero charge in aqueous solutions

The synthesis of magnetite by the method of co-precipitation is one of the most used and reported methods in the literature for the production of nanoparticles with magnetic properties. Nanotechnology and its applications to remove organic contaminants in wastewater treatments is an area of great interest. Conventional techniques in the wastewater treatments plants cannot effectively remove all the organic contaminants present at trace levels and the use of the nanotechnology in treatments plants can be an option to remove these contaminants. In this study we analyzed the nanoparticle magnetite sodium-oleate, functionalized with a (sulfactant) to increase its hydrophobic particle layer and thus increase the adsorption of hydrophobic contaminants such as hormones. Physical and chemical properties of the nanoparticle, such as point of zero charge and infrared spectra were evaluated for the determination of charges and functional groups on their surface. The “Point of Zero Charge” of the nanoparticles magnetite-sodium oleates range from 6.8-7.8 was analyzed with different ionic strength solutions.

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Perez-Perez, Lizzette

Acosta Colón, Angel A.


Geochemical Analysis on Bat Guano for Matos Cave at Arecibo, P.R.

The Matos Cave STEM project is a research project that combines students of different STEM areas and integrated them into geosciences and speleology. Matos Cave is located in the north coast karst belt region of Puerto Rico (Aymamón limestone formation), specifically in the municipality of Arecibo. The cave is located subtropical moist forest biome and it’s the habitat of more than 50,000 bats. The cave is the home for mainly three types of bats: Artibeus Jamaicensis, Erophylla Bombifrons and Brachyphylla Cavernarum. The bats colonies are separated in the cave due to the temperature gradients created by the bat population, droppings and exterior temperature. This study presents a geochemical analysis of the bat guano found at the surface of the cave. The analysis consisted in measuring the pH, nutritional composition (loss on ignition and hydrogen peroxide digestion) and chemical and mineral composition by using Fourier Transform Infrared (FTIR) spectroscopy methods. The cave can be divided in three zones, each one with a specific bat population, for statistical purposes we divided the cave by its geometry and selected 11 sampling sites and one outside the cave for soil reference. For each sites we collected the bat guano and measured the pH, nutritional composition and mineralogy of the bat guano. The pH varied from neutral (outside sample) to acidic as a function of the depth of the cave or bat species. The nutritional composition varies from 10 to 70 % and doesn’t have a particular pattern. The combination of nutritional composition (energy available) and pH (toxicity of soil) provides what the soil mesofauna need to have a stable ecosystem. The geochemical composition (mineralogy) results such as calcite, gypsum, clay, etc. are measured using FTIR for a complete characterization of the bat guano. In conclusion, this study presents a methodology to characterize the bat guano-soil of the cave and this results can be used to understand the assemblage of organisms that varies depending on the species of the bat producing, i.e. the soil mesofauna of the cave.

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Perez-Soto, Luis

Morales-Soto, Wilmarie - Department of Biological Sciences, University of Puerto Rico-Cayey


Classifying Land Cover Composition of La Plata Watershed in Puerto Rico Using Historical Aerial Photography and Object Classifiers

Reconstructing the transformation of tropical watershed allows for researchers to understand the possible causes of change and the spatial patterns that results from social and environmental changes. Puerto Rico has a rich history of aerial photographic surveys that allows for doing spatially explicit reconstruction of the history of landscapes change since the 1930s. This allows us to perform a historical land cover transformation analysis for La Plata River Watershed in Puerto Rico. To analyze land cover transformation we utilize satellite imaging for the years 1930, 1960 and 2010. In these images we have created the land use classes of agriculture, forest and anthropogenic utilizing the remote sensing raster graphic editor of eCognition. This program allows us to create this previous mention classes based on specific parameters and algorithms. Our aim is to determine or identify a possible pattern in the land cover transformation for our study area. The results show that agricultural valleys have been mostly urbanized, while mountainous regions have given way to forest. A fine scale analysis of forest transformation shows clearly how remnants of previous uses, aspects, slope and elevation affects the future composition of the forest. The understanding of the patterns of change on this time scale will provide a better understanding of forest and anthropogenic area transformation in Puerto Rico.

Plaza-Muniz, Keishla

Sanders, Ilse - Biology, UIA-SAN GERMAN


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Distribución y movimiento del sábalo (Megalops atlanticus) en el Refugio de Vida Silvestre Iris L. Alameda Martínez, Cabo Rojo.

Los sabalos (Megalops atlanticus) habitan en zonas estuarinas de Puerto Rico y su pesca es de alto valor recreativo. En septiembre del 2014 se llevo a cabo un estudio para determinar el movimiento y la abundancia de los sabalos habitando los canales y lagunas del Refugio de Vida Silvestre en Cabo Rojo. Los individuos capturados fueron marcados con un “PIT-tag” y detectados al pasar por dos antenas, la #1, localizada en el extremo noreste de la laguna y la #2, localizada en el lugar donde el canal abre hacia la laguna Rincon. Utilizando el numero de detecciones, las fechas de captura, las fechas en que fueron detectados, y tamanos durante el 2014, se estudio el movimiento de los peces entre las dos antenas, y la direccionalidad de su movimiento. Al comenzar el estudio, habia 1,243 sabalos marcados, y se continuaron marcando hasta diciembre. Nuestros resultados muestran que en la #1 hubo un mayor numero de detecciones en febrero y de agosto a octubre, con un total de 44,811 detecciones provocadas por 96 individuos, mientras que en la #2, el mayor numero de detecciones ocurrió de abril a octubre, con un total de 341,062 detecciones por 213 individuos. La precipitacion total de los meses de junio a noviembre fue de 21.22 pulgadas, mientras que entre enero a mayo se registraron 14.44 pulgadas, por lo que cambios en el nivel del agua ocasionados por los distintos niveles de precipitacion pudiesen estar relacionados a cambios en el numero de peces y de detecciones.

Reyes-Maldonado, Koralis

Soto, Francisco - Department of Environmental Sciences, UPR-Rio Piedras; Sabat, Alberto - Department of Biology, UPR- Rio Piedras


Demography of a resilient and susceptible coral species

A longitudinal demographic study of the susceptible (Orbicella annularis) and resilient (Porites astreoides) coral species is underway at a pristine (Carlos Rosario reef) and impacted (Palominos) site in Culebra and Fajardo municipalities in Puerto Rico‚ respectively. At each site we established a 30m long transect in which 100 colonies of (O. annularis) and (P. astreoides) have been marked and photographed to follow their fates. We have completed the first census for both species at both sites. This will allow us to perform demographic analysis for both species at the two sites. The asymptotic population growth rate (?) calculated from the transition

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matrices for both species indicate a higher growth rate for the O. annularis population in Culebra (?=0.9692) than for P. astreoides (?=0.8925). However‚ it should be pointed out that these growth rates estimates do not include recruitment (we are still analyzing this data). We expect no recruitment in O. annularis (thus no change in ?)‚ and high recruitment in P. astreoides (thus a significant increase in its ?). O. annularis is exhibiting higher survival and lower partial tissue mortality (i.e. retrogressions) than P. astreoides at the Culebra site. This translates into a higher asymptotic population growth rate for O. annularis at the Culebra site. However‚ once we incorporate the effect of recruitment into the analysis‚ we expect a higher population growth rate for Porites. This reflects differences in the life history strategies of both species; O. annularis investing more in survivorship‚ and P. astreoides more in reproduction.

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Reyes-Rivera, Arsenio

Reyes Rivera, Arsenio Luis - Department of Chemistry, University of Puerto Rico; Diaz-Vazquez, Liz M. - Department of Chemistry, University of Puerto Rico


Aerogel as Biosensor; Detection of Emerging Organic Pollutants by Aliivibrio Fischeri Immobilization on Large Pore Aerogels

Previously, we had confirmed that some explosives, illicit drugs and environmental pollutants can penetrate the structure of different aerogels. In the current experiment, a bacterium was immobilized in different porous aerogels and its presence was detected by its capacity to produce luminescence. Aliivibrio Fischeri was passed through aerogels disc at a flow rate of 2 mL/min. The discs were incubated in a bacterial growth media for two hours. The luminescence of each aerogels was measured in an illuminometer confirming that the bacteria survived the condition of the aerogel. The monomers under study were Methacrylic Acid (MAA), Norbornene (NB), Acrylamide (AA), and Silica. This demonstrates that these bacteria can penetrate the structure of different aerogels and produce a response. The analysis was completed using Scanning Electron Microscopy (SEM), Fourier Transform Infrared Spectroscopy (FTIR) and Thermogravimetric Analysis (TGA). Furthermore, the capacity of the aerogel-bacteria system to detect different emerging contaminants in water samples was studied. Biopolymers made of carbohydrates like Chitosan, Alginate and Carrageenan are also being tested.

Reyes-Torres, Limarie

Torres, Pedro - Odum School of Ecology, University of Georgia


The role of Phylloicus Pulchrus (Trichoptera: Calamoceratidae) in the decomposition of leaf litter: evaluating leaf species and case building effects

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Phylloicus pulchrus larvae are exclusive leaf feeders, and they are known to be key contributors to the processing of leaf litter in tropical streams. Previous studies have used P. pulchrus larvae to determine feeding preferences, case building behavior, growth and survival rates in order to better understand their role as shredders. However there is limited information on their effects on decomposition in terms of the material used for consumption and the material used for case building. We determined the influence of P. pulchrus on leaf litter decomposition in the streams of Puerto Rico. Our main goals were to assess the effects of leaf species and their availability on leaf decomposition by P. pulchrus and to evaluate the effects of leaf selection for case building by P. pulchrus. Our results indicate that this tropical shredder is able to discriminate among different leaf species that differ in structure and chemical composition resulting in differences in decomposition rates among leaf species. Our findings indicate that leaf decomposition rates are affected by whether leaves are used for case building or consumption. This study is the first to provide data on P. pulchrus preferences between native leaf species in Puerto Rico. P. pulchrus behavior may potentially play a major role in ecosystem processes, such as FPOM transport, since the case material is not released into the water column.

Reynoso-Garcia, Jelissa


QUALITY OF RAIN IN THE CITY OF SAN JUAN, PUERTO RICO

As in other parts of the developing world, anthropogenic activities affect water quality in Puerto Rico. The objective of this project is to determine whether human activities that emit gases into the atmosphere such as vehicles exhaust systems and industrial emissions can alter the chemistry of the rain that falls in the city of San Juan, Puerto Rico. The hypothesis of this project is that the chemical composition of the rain that falls in an urban area reflects the effect of the activities of the urban environment. This study monitors weekly the quality of the rain that falls on a weather station located at the Rio Piedras Botanical Garden. This station has an automatic rainwater collector designed to only capture wet and not dry deposition. Weekly and prior to each sampling, the sampling collector is prepared following a standard cleaning protocol. Every week the sampling collector is removed and replaced with another clean collector. Finally, the sample is processed in the laboratory where pH and conductivity is measured and the water is filtered for analysis of common ions. The data will be analyzed through a comparison between the urban station and a control station located upwind in El

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Yunque and operated by the National Atmospheric Deposition Program. This project presents preliminary data to document for the first time differences between the chemistry of rain between a tropical city and a forested area in Puerto Rico.

Rios-Estremera, Daniel

Ierkic, Henrick - Electrical and Computer Engineering, UPR-Mayaguez


Upper Air Soundings over Puerto Rico

Our research focuses on creating a computer tool to help study the data provided by radiosondes, in order to better understand the atmosphere and meteorological phenomena, and to find evidence that supports the presence of inertial-gravity waves. The radiosonde data for Puerto Rico was provided online by the University of Wyoming. Secondary radiosonde data was provided online by the University of Puerto Rico in Mayaguez. The tool developed was a Matlab computer program, that resulted on a tested robust main program with over 2000 lines of code and 30 complementary function algorithms, designed to: read the radiosonde data, analyze and visualize it, and derive other meteorological parameters, utilizing different calculations and plotting methods. The program recognizes the dates and data available, and can process data from particular radiosonde launch times, or from launches made during an interval of time. By analyzing Skew-T diagrams and CAPE values from the summer 2014 data, it was observed that although Skew-T diagrams had similar temperature curves, dew point temperatures varied greatly. Thus, the atmospheric instability in Mayaguez diverges from that of San Juan, as CAPE values calculated for them often varied by several hundred J/kg. As for wind velocities, the altitude at which velocity peaks is similar between Mayaguez and San Juan. Furthermore, wind analysis seems to suggest the presence of inertial-gravity waves in the atmosphere. Further analysis, and study of other sources of meteorological information are needed to determine whether these behaviors observed are solely due to the presence of inertial-gravity waves.

Rivas-Pagan, Samelia

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Nicole Lopez Pena - Chemistry, University of Puerto Rico at Humacao; Reyna Algarin Santos - Chemical Engineering, University of Puerto Rico at Humacao; Dr. Rolando Tremont - Chemistry, University of Puerto Rico at Humacao


Heavy metals in living beings and water from Cabo Rojo salt water bodies

This study is based on the determination of some heavy metals and arsenic in oysters from the area of Cabo Rojo, Puerto Rico West. Samples are taken to the laboratory, and an oven dried, then placed in 50% HNO3 heating for 30 min. The resulting solution is filtered and brought to 100 mL in a volumetric flask. Finally, the concentration of heavy metals (Pb, Hg, Cd, Cu) and arsenic are determined by Atomic Absorption. The results will be appearing in my presentation.

Rivera-Alvarado, Angelica M.

Calo Guadalupe, Cristian - School of Science and Technology, URGREAT-MBRS-RISE, Universidad Del Este ; Rivera Mariani, Felix - Miami Dade College; Bolaños Rosero, Benjamin - Department of Microbiology and Zoology, University of Puerto Rico, School of Medicine


Assessment of the Allergenic Potential of the Tropical Pollen from the Trumpet-Tree (Cecropia schreberiana), the most common Pollen in Puerto Rico

Allergic respiratory diseases, such as allergic rhinitis and asthma, are chronic conditions very prevalent in Puerto Rico. About 14% of children have asthma in PR compared to less than 9% in the USA. We have determined that pollen of the trumpet-tree, Cecropia schreberiana, is the most common pollen in PR. It is not known if this pollen may be allergenic, but due to its small size (6 um x 9 um) and high frequency in the outdoor air, it may pose an allergic risk to susceptible individuals. The purpose of this study is to determine the allergenic potential of C. schreberiana using the halogen immunoassay. This assay detects the reactivity of

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the IgE from individuals to the pollen grains by the use of a conjugate of polyclonal goat anti-human IgE by the formation of violet halo around the reactive pollen grain. The pollen was collected from the flowers of the trumpet-tree and transferred onto a thermal-adhesive transparent tape. The pollens particles were sealed with a protein binding membrane to trap the release of allergens. The membranes were exposed to different dilutions of sera from individuals with allergies or healthy volunteers. The halo formation was documented at the microscope and analyzed by an analysis image software Image J. This is the first study testing for the allergenic potential of the most common pollen reported at the outdoor air in PR. It may explain the peak of asthma-related hospitalizations observed during the pollen season in PR.

Rivera-Garcia, Isamarie

Santiago, Vanessa - Biology, Univerity of Puerto Rico; Duquesne, Yanice - Biology,University of Puerto Rico; Ruiz, Claudia - Environmental Siences, University of Puerto Rico; Rodriguez, Alexander - Environmental Siences, Univerity of Puerto Rico; Perez, Xochitl - Environmental Siences, University of Puerto Rico; Roberson, Loretta - Environmental Sciences, University of Puerto Rico


Annual variation in the presence of contaminants of emerging concern in the San Juan Bay estuary

Waterbodies, to which we frequent, are full of chemicals that come from industries or other anthropogenic inputs and may be at low concentrations or unregulated but can equally affect us. These chemicals are known as contaminants of emerging concern due to their unknown but possibly important impacts on local ecosystems. The San Juan Bay Estuary was selected for this study because it is a strategic point that receives waste waters from industrialized and urban areas and provides a number of essential ecosystem services including fisheries for human consumption. We sampled 16 sites within the estuary from 2012-2014 and extracted semi volatile and volatile organic compounds using Solid Phase and Liquid-to-Liquid Extraction coupled to gas chromatography and mass spectrometry. To date we have found a total of 77 compounds that can be classified into six different categories: fuels, hydrocarbons, multi-use, personal care products, pharmaceuticals and plasticizers. Our data shows that in the San Juan Bay Estuary some pollutants are repeated over the years, others disappeared, and new compounds appeared. We will present

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the most persistent compounds and compare their variation among sites and among years.

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Rivera-Ramirez, Cristina Isabel

De Jesús-Villanueva, Christina - Department of Biology, University of Puerto Rico, Rio Piedras; Vélez-Zuazo, Ximena - Department of Biology, University of Puerto Rico, Rio Piedras; Falcón, Wilfredo - Institute of Evolutionary Biology and Environmental Studies, University of Zurich; Stephen, Catherine - Department of Biology, Utah Valley University; Papa, Riccardo - Department of Biology, University of Puerto Rico


Where did the green invaders come from? Identifying source populations of the invasive green iguana Iguana iguana in Puerto Rico

The green iguana Iguana iguana is classified as an invasive nuisance in Puerto Rico due to its negative effects on agriculture and road infrastructure. Although it is considered invasive in multiple countries, the green iguana has been listed in CITES Appendix II. This international protection if afforded to species that could become overexploited and consequently threatened by their trade. Although the iguana was introduced to Puerto Rico over 30 years ago, little is known about their introduction history. Our objective in this study is to determine the source of the invasive populations in Puerto Rico by utilizing molecular markers. To achieve this, we will use mitochondrial (ND4) and nuclear (NT3 and PAC) DNA markers to compare populations across five locations on the island. We will complete a phylogeographic analysis for each gene in combination with published data from native range to assess their origin. We expect that the results of this study will provide us with a more in depth understanding of the origin of the I. iguana and serve as a tool for management of this invasive reptile in Puerto Rico and in the rest of its invasive range.

Rivera-Santiago, Harold

Echevarria Rivera, Hector - Physics / Chemistry, UPR - Arecibo; Rivera Pérez, Frank - Physics / Chemistry, UPR - Arecibo; Romero Pérez, Steven - Physics / Chemistry, UPR - Arecibo

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Quantitative Analysis of Ethanol Production From Sorghum Syrup

Ethanol biofuel was produced from sweet sorghum extract. Simply stated, the extract was diluted from 80% brix down to 15 to 35 % in an aqueous solution, fermented with Saccharomyces cerevisiae and the the broth analyzed for ethanol content. Results showed that the ethanol concentration is maximum at around 25 % brix. A mass balance based on brix confirmed the ethanol content. The results of this investigation will be presented. On the other hand, the potential to use sorghum crops for biofuel as an alternative to sugar cane will be presented as well.

Rodriguez-Corchado, Jomar

Acosta- Colon, Angel A. - Physics and Chemistry Department, University of Puerto Rico at Arecibo


Characterization of Rio Abajo Cave

The Matos Cave STEM project is a research project that combines students of different STEM areas and integrated them into geosciences and speleology. Rio Abajo Cave is located in the north coast karst belt region of Puerto Rico, specifically in the borderline between the municipalities of Arecibo and Utuado. The main objective of this study is to understand the geological, geometrical, geophysicochemical and geobiological properties of the cave and its relationships between them. The geological properties were found from a literate review of the study of the region. The geometrical properties were measured using laser digital laser distance measurer, clinometer and a compass to create 2-D and 3-D maps of the cave, this can be used as a reference for the other properties that were measured. The geophysicochemcal properties consisted in the soil pH, temperature and humidity of the cave. Also, the geobiological properties were studied by analyzing soil samples from the cave. By understanding all these properties and their relationship we can complete characterize Rio Abajo Cave and increase the understanding of different STEM fields for a particular case.

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Rodriguez-Gonzalez, Mayra

Leh, Mansoor - Department of Biological & Agricultural Engineering, University of Arkansas; Matlock, Marty - Biological & Agricultural Engineering, University of Arkansas


Measuring land use change effects on multiple Ecosystem Services in Puerto Rico for future decision making

Changes due to natural and anthropogenic disturbances have led to poor land management in Puerto Rico. Land use change has been impacted by a shift from an agrarian to a manufacturing industry based economy. There is a lack of studies of land use change impacts on ecosystem services in Puerto Rico. This study assesses land use change impact on biodiversity and ecosystem services availability in Puerto Rico through the Integrated Valuation of Ecosystem Services and Tradeoffs (InVEST) tool. Mixed changes were obtained due to the general decrease of agricultural practices and increase of both urban and forested areas. This study could serve as benchmark in land managers’ decision making process when exploring possible land use scenarios for Puerto Rico.

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Rodriguez-Velazquez, Adolfo

García Flete,Wilmary - Ciencias Naturales, Universidad del Sagrado Corazón; Rivera Torrado, Gabriela - Ciencias Naturales, Universidad del Sagrado Corazón; Torres Gonzalez,Gertudris - Ciencias Naturales, Universidad del Sagrado Corazón


NATURAL HISTORY AND PHYLOGENETIC RELATION OF THE TROGLOBITIC AMPHIPODS OF PUERTO RICO: FIRST PHASE FINDINGS

Troglobites are species that have undergone genetic changes that confine them to the cave environment. Of the 13 troglobites known to Puerto Rico, six (6) are aquatic crustaceans. The Order Amphipoda, represented by two (2) species of the genus Metaniphargus and one (1) of the endemic genus Alloweckelia, presents the greatest diversity. Of these, M. bousfieldi is a saline-water specie found in the Guánica State Forest caves, whereas an undescribed Metaniphargus and Alloweckelia gurneei, are found in fresh-water habitats at caves within the Camuy River drainage basin. In order to examine and further validate hypotheses about the evolution, speciation and dispersal of such species, a molecular assessment of their phylogenetic relation using DNA sequences from the mitochondrial ribosomal RNA gene (16S rRNA) was proposed. At present, the study first phase, directed to the collection of the elusive specimens and characterization of their aquatic habitat is completed. Relevant findings concerning population dynamics, dispersal capacity along the limestone matrix and susceptibility to water-quality changes (e.g. temperature and dissolved oxygen) are discussed.

Rodriguez-Velazquez, Jenissa

Alamo-Nole, Luis - Chemistry, Pontificial Catholic University of Puerto Rico; Rodríguez-Velázquez, Jenissa - Chemistry, Pontificial Catholic University of Puerto Rico


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Phytoremediation of nanoparticles using "Ocinum basilicum"

Phytoremediation is a cost effectively and eco-friendly process that use plants to solve environmental problems. Heavy metals such as mercury, arsenic, nickel, cadmium and others are common sources of soil pollution. Phytoextraction have been used for soil restauration after metal contamination. In our investigation Ocimum basilicum “basil” was used for the phytoextraction of cadmium in ionic form and nanoparticles. Basil has important properties, such as their fast grow, that benefit the data collection. The plants germinated and grew up in an environmental chamber under regulated temperature (27°C) and light. The irrigation was controlled during the experiment to avoid leaking from the soil. Data collection about the height, temperature and other observations was constantly registered. The plants (48) were divided in 5 groups: blank, 25 ppm of cadmium solution, 25 ppm of cadmium nanoparticles, 50 ppm of cadmium solution and 50 ppm of cadmium nanoparticles. The plants were analyzed after 3 and 6 weeks of exposition to the contaminants. The length of the stem and root and the mass of roots, stem, leaves and flowers was recorded. The samples were oven dried and digested in a microwave system. Finally, the samples were analyzed by ICP to determine the concentration of cadmium absorbed by the plants.

Rodriguez-Velazquez, Jose David

Keila Velazquez Arcelay - School of Science and Technology, URGREAT-MBRS-RISE, Universidad Del Este, Carolina, Puerto Rico; Hector Orozco Mercado - School of Science and Technology, URGREAT-MBRS-RISE, Universidad Del Este, Carolina, Puerto Rico; Ashley Aviles Noriega - School of Science and Technology, Universidad Del Este, Carolina, Puerto Rico; Nomarys Delgado Negron - School of Science and Technology, Universidad Del Este, Carolina, Puerto Rico; Karlo Malave Llamas - School of Science and Technology, URGREAT-MBRS-RISE, Universidad Del Este, Carolina, Puerto Rico


Ecosystemic Microbiome Assessment of Caribbean Beaches: Apropos Coral Reef Decay and the Impinge on Humans.

Across the Caribbean, beaches are found to have unique ecosystems. Rising sea temperatures and the emergent downfall of certain primal species in these networks (e.g. coral reef) may influence the microbiome make-up. Giving the possibility for pathogenic bacteria to proliferate in the environment. The objective, to evaluate: the

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microbiome, anthropogenic influence, and extant abiotic parameters of three beaches sub-divided by zones. Triplicated water samples from each zone using a dilution factor of 10-3, were filtered through a 0.45µ membrane, cultured in an array of selective media, and identified with the BIOLOG©. Coral pathogen Vibrio harveyi, human opportunistic pathogen Klebsiella oxytoca, and nosocomial pathogen Acinetobacter baumannii were the most significant isolates. Thenceforth exposed to seven common antibiotics to assess their resistance; 19 out of 20 isolates were resistant to penicillin (10µg), as well as 15 out of 20 were resistant to vancomycin (30µg). Noting that the samples collected were from the environment, high levels of resistance to a variety of customary antibiotics was observed; favoring the objective of finding indications of anthropogenic impact. Moreover, fungi existence was observed, growth in selective medium SDA bared both filamentous fungi and yeast, like Aspergillus niger and Trichosporon beigelii A – respectively. These microorganisms become important when reports showing poor response to antifungal agents, and high mortality rates are considered. This ongoing assessment has preliminarily provided a better understanding of factors to be well-thought-out; thus, improving the scope on outcomes of soaring sea temperatures.

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Rolon-Rios, Jeilene

Mejía, Heber - Biology, UPR-BAYAMON


The gram negative bacteria serve as bio-environmental indicators to detect contamination by heavy metals in aquifers?

In Puerto Rico the reservoirs are the main source of drinking water. However, these are susceptible to contamination by human activities in the surrounding areas. This study determined if there is contamination with heavy metals in Lake La Plata and if gram negative bacteria can be a bio-indicator of this type of pollution. We proposed that more than 50% of the gram-negative bacteria would show resistance, and that heavy metal resistance would increase in the littoral zone. To test our hypothesis, we collected water between the littoral zone, shore, and limnetic, center, to isolate the bacteria. We determined their resistance to various heavy metals, Pb, Cu, Zn and Mg, and contrasted the response between both zones. The Kirby Bauer method was used to measure resistance. We found that more than 50% of the bacteria showed resistance, being Zinc the only heavy metal for which bacteria presented no resistance. We observed a trend in our results that proved greater resistance in the coastal area in contrast to the limnetic, but this was not statistically significant. In conclusion, the bacteria in the Lake have resistance to heavy metals, suggesting that these are exposed to them in their natural environment. In the future it would be necessary to identify and classify the specific bacterial community to better understand their mechanism of the resistance.

Santiago-Cardenas, Vanessa

Perez, Xochitl - Department of Environmental Science, UPR-Río Piedras, San Juan, PR; Ruiz, Claudia - Department of Environmental Science, UPR-Río Piedras, San Juan, PR; Rodriguez, Alexander - Department of Chemistry, UPR-Río Piedras, San Juan, PR.; Duquesne, Yanice - Department of Biology, UPR-Río Piedras, San Juan, PR. ; Rivera, Isamarie - Department of Biology, UPR-Río Piedras, San Juan, PR. ; Roberson, Loretta - Department of Environmental Science, UPR-Río Piedras, San Juan, PR.

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Annual variation in persistent organic compounds in the San Juan Bay Estuary

Persistent organic pollutants are chemicals of interest consistently found at low concentrations in the environment that could potentially be harmful to human health and the environment. In this study we monitored the concentrations of ten contaminants of emerging concern annually from 2012-2014 at 16 stations in the San Juan Bay Estuary of Puerto Rico. Water samples were processed by solid-phase extraction using methyl acetate as elution solvent and by liquid-liquid extraction using methylene chloride as solvent. All samples were analyzed by Gas Chromatography-Mass Spectrometry and identified with AMDIS-NIST program. The results show that several compounds such as dibutyl phthalate are persistent in the estuary, appearing in most sites every year. Most compounds show the influence of human activity on marine waters; also water flow may be responsible for differences in concentrations among sampling sites. With this analysis we can have a better understanding of the ecosystem and the risk to estuary organisms.

Santiago-Gonzalez, Iliansherry

Hurley, Stephanie - Department of Plant and Soil Science, University of Vermont; Shrestha, Paliza - Department of Plant and Soil Science, University of Vermont


Heavy metals and phosphorus filtration in stormwater runoff using bioretention systems at UVM Bioretention Laboratory

Bioretention filters known as raingarden is a green infrastructure that improves water quality by infiltrating and removing pollutants through various physic-biochemistry mechanisms, and simultaneously reduces surface stormwater runoff. These Bioretention systems are located at University of Vermont adjacent to a parking lot to catch stormwater runoff from the roadsides. General bioretention soil media comprised of sand, compost, pea stone and gravel and 7 plant species mixes. Two treatments were examined general soil media (i) with and without added precipitation and (ii) Phosphorus Sorbtive Media additive to soil with and without added precipitation. Water samples were collected using automatic samplers (ISCO 7000) after major storm events from the inflow and outflow by cell.

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Total phosphorus (TP), soluble reactive phosphorus (SRP), heavy metals concentrations were analyzed in water samples. Some heavy metals analyzed were zinc, lead, iron, manganese and copper. Preliminary results show that Sorbtive Media treatment with added precipitation it removed about 88% for SRP, while it exported 22% of TP. Sorbtive media without added precipitation removed 12% of TP and 49% of SRP. Heavy metals percentage removals from precipitation treatment ranged from 5% to 100% for zinc, lead, copper and manganese. The comparisons of removal and exportation concentrations of pollutants by each cell will be discuss through this presentation. Also, the examination of whether the differences varied across treatments. These preliminary results show that bioretention can remove some pollutants while export others depending on the design characteristics (e.g. what is used in the bioretention media).

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Santiago-Rodriguez, Giancarlo

Santiago, Giancarlo - Natural Science Department, Inter American University of Bayamon; Vardar, Nedim - School of Engineering, Inter American University of Bayamon


Passive and Active Sampling for Persistent Organic Pollutants (POPs) in Bayamon, Puerto Rico.

The persistent organic pollutants POPs are semi-volatile chemicals; therefore they can exist both in gas and particle phases. POPs are routinely emitted into the atmosphere either naturally or by human activities such as industrial sources and motor vehicles. A PUF passive sampler consisting of polyurethane foam disks housed in two stainless steel bowls, and a high volume sampler have been employed at two different locations in Bayamon. Short term 12 hours high volume samples and long term three months passive samples were taken atBayamon campus of Inter American University and in a residential area at Avenida Hermanas Davilas in San Fernando, Bayamon. The target compounds for this study are polychlorinated biphenyls PCBs, polycyclic aromatic hydrocarbons PAHs and organo-chlorine pesticides OCP. Preliminaryhigh volume sample results showed thatthe total concentrations of 15 PAHs varied from 2.84 to 4.12 ng/m3 for the campus, and from 6.71 to 12.41 ng/m3 for the residential area samples. The average concentrations of ?15-PAHs in residential samples were approximately three times higher than those of campus samples.In order to better interpret the PAHs results, HYSPLIT model trajectories were calculated using meteorological data provided in the NOAA website. Internal combustion related car emissions, evaporation from neighboring gas station, abrasion of rubber tires, and brake linings can be considered as the main reason of those increased PAHs levels obtained from the residential samples. In near future, the analysis of the PCBs and OCPswill be performed using a Varian 450-GC coupled to an ion trap mass spectrometer,Varian 240 MS.

Sotomayor-Pabon, Jennifer

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Determinación de la presencia y concentración de metales pesados en la Reserva Natural Punta Cucharas de Ponce

La Reserva Natural Punta Cucharas de Ponce es un área que fue designada por su nombre bajo la ley 227 del 9 de agosto de 2008 del Departamento de Recursos Naturales de Puerto Rico. El propósito de esta investigación es determinar la presencia y concentración de metales pesados en esta Reserva Natural de Ponce, Puerto Rico. Para analizar el propósito se realizará un muestreo de metales pesados, dado que esta reserva es una costera que tiene contacto con el Mar Caribe y los niveles de evaporación son muy altos, por lo que el porcentaje de salinidad y sólidos en el agua es alto: haciendo de esta laguna una hipersalina. Para esta investigación se estarán recopilando muestras en dos puntos, que serán identificados como punto A y punto B. Se recopilarán dos muestras por cada punto, es decir, cuatro muestras. Estas muestras se tomarán a un metro de profundidad y cerca del fondo de cada punto estudiado. El motivo de tomar dos muestras es determinar la concentración de metales pesados a distintas profundidades. Estas muestras se analizarán mediante un Inductor de Plasma Acoplado por Emisión de Espectroscopia óptica (ICP-OES 3300 XL). Las emisiones emitidas por el plasma son policromáticas, estas son separadas en largos de onda individuales. La emisión de cada sustancia excitada es identificada por el instrumento y su intensidad es medida sin interferencias de emisiones a otros largos de onda. Estos largos de ondas ayudarán a determinar que métales pesados se encuentran y a qué concentraciones en la Reserva Natural Punta Cucharas de Ponce. Para analizar los resultados de la presencia y concentraciones de los metales pesados en la reserva se usará estadística descriptiva e inferencial. Estos resultados se utilizarán para monitorear la calidad de agua de esta Reserva Natural.

Vera-Santiago, Paloma

Ramos-Fontán, Maiella, - Department of Physics-Chemistry, University of Puerto Rico at Arecibo


Bioremediation of Nickel and Cobalt by Bacopa monnieri

There has been a strong interest in the use of aquatic plants as a potentially useful group for pollutant uptake, like heavy metals, in aquatic systems. Bacopa monnieri

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is an excellent candidate because its heavy metal accumulating potential has been tested with the ions cadmium, iron and chromium. B. monnieri was also chosen because it is a medicinal herb used to treat anxiety, improve focus and memory. These aquatic plants were collected at the Caño Tiburones wetland and transported to the research laboratory for sample treatment and analysis. In this study we investigated the uptake of nickel (Ni) and cobalt (Co) by B. monnieri after being treated with different concentrations of the ions (1 ppm, 2 ppm, 4 ppm and 6 ppm) individually in separate containers. Plant tissue was sampled weekly and water was sampled every two days. Plant samples were treated with wet digestion method using 5 mL of concentrated nitric acid (70% w/w) and 10 mL of hydrogen peroxide (30% w/w). Also, by applying mass balance, an analytical equation was developed to estimate how fast is the heavy metal uptake by B. monnieri. Analysis was performed by means of an atomic absorption spectrophotometer, using a flame atomizer (PE Analyst 200). Preliminary results showed that, after 12 days, a decrease in Ni concentration was obtained in water samples treated by plants. Further research will allow us to study the capability of this aquatic plant to uptake other heavy metals.

186

Vicens-Lopez, Coralys

Agosto-Torres, Eliacim - Biology, University of Puerto Rico–Humacao ; Hernández-Muñíz, Rayza - Biology, University of Puerto Rico–Humacao ; Bernardi-Salinas, Ashley - Biology, University of Puerto Rico–Humacao ; Ríos-López, Neftali - Biology, University of Puerto Rico–Humacao


Population Ecology of the Puerto Rican Mountain Coquí, Eleutherodactylus portoricensis from a mountain forest at the Sierra de Cayey

The Mountain Coquí, Eleutherodactylus portoricensis, is a mediun-large sized frog (mean SVL ~ 32.0 mm) found in high elevation forests at El Yunque and Sierra de Cayey. Presumably, the species has undergone drastic population declines at El Yunque and local population extinction in all the Cordillera Central, except at the Sierra de Cayey. The species is designated Vulnerable by the Department of Natural and Environmental Resources of the Commonwealth of Puerto Rico and Endangered on the IUCN Red List. Interestingly, little is known on the species population ecology elsewhere, including the region of its highest genetic variation, the Sierra de Cayey. Here we document the species population phenology, population density, habitat use, and demography from a high elevation forest in Cayey and contrast these parameters in relation to the local Eleutherodactylus assemblage. In this forest, the Mountain Coquí is four times more abundant than the most abundant Eleutherodactylus in Puerto Rico, the Common Coquí. Similar to other Eleutherodactylus, the population density varies with ambient temperature and rainfall: it reaches the highest density during months of higher ambient temperature and rainfall (May to November), and decreases during months with lower temperature and rainfall (December to April). On average, adult individuals comprises ~33% of mean total population size (~2140 individuals ha-1), a population size is as high or higher than the population size documented for the Common Coquí at similar elevation forest sites at El Yunque.

Virella-Maldonado, Nicole

187


Evaluating the vulnerability of the dune formations in the urban area of Carolina and Loíza with the use of geomorphic and anthropogenic parameters

Coastal ecosystems and formations in Puerto Rico present a diverse and complex area of study, especially since it’s an island and islands can have a wide range of environments in a small geographical space, in comparison with the continental coasts found around the world. Within these diversity of coastal environments sand dunes are one of the most dynamic and important because they function as reservoirs of sand, available for supply to the beach during storms, while protecting the coastal land from flooding and serving as a buffer from high energy waves. However, the importance of this geomorphic formations is sometimes belittled, creating an urgent need to evaluate such sand formations, especially since much of the coast of Puerto Rico has a high concentration of people living close to the beach. The anthropogenic factor is key since it can increase the vulnerability of the sand dunes, resulting in the degradation of such formations. In order to evaluate the dunes a vulnerability assessment was necessary. Therefore this study selected two different coastal zones of Puerto Rico. Both were then characterized in order to calculate the vulnerability of the dune formations using a vulnerability checklist that included geomorphic and anthropogenic parameters. This index provides a better understanding of vulnerability of the dune formations in the selected areas. Also the use of GPS enabled us to locate the most vulnerable dunes and preliminary results have shown that there’s a high anthropomorphic impact, which could threaten the sand dunes, especially in the area of Carolina.

188

Geosciences

189

Ledesma-Maldonado, Karimar

Geosciences

Physicochemical evolution of Saharan mineral dust aerosol during the transport over the North Atlantic Ocean

African deserts are the source of approximately 800Tg/year of mineral aerosols that are suspended in liquid and solid form in the global atmosphere. Understanding the physical and chemical properties of these aerosols is important because that have a significant global impact in four areas of concern: atmospheric chemistry, climate, biogeochemical cycling and environmental health. During the winter 2013 AERosols and Ocean Science Expeditions (AEROSE) field campaign, samples of suspended mineral dust particulate were collected over the tropical Atlantic Ocean during a one-month period (January and February 2013). The purpose of this endeavor was to obtain data and perform analyses that would elucidate our understanding of the evolution of fine mineral aerosol dust during transport across the tropical North Atlantic. A scanning electron microscope (SEM) equipped with an energy dispersive x-ray scattering (EDX) spectrometer was used to examine the morphological characteristic and surface chemical composition of the individual particles obtained in the AEROSE samples. Principal Component Analysis (PCA) was used to determine relationships between the size distribution, element enrichment, and atmospheric lifetime. The source regions of the individual events were determined using a combination of satellite image analysis, back-trajectory modeling, and analysis of global forecast models.

Nunez-Ocasio, Kelly

Aberson, Sim - Hurricane Research Division, National Oceanic Atmospheric Administration; Zhang, Jun - Hurricane Research Division, National Oceanic Atmospheric Administration

Geosciences

190

An Extreme Event in the Eyewall of Hurricane Felix

On September 2, 2007, a NOAA P3 Aircraft penetrated one of the most rapidly intensifying hurricanes on record: Hurricane Felix. The mission had to be terminated due to intense turbulence as a consequence of severe horizontal and vertical winds; however, valuable data were obtained from the flight. The objective of this research is study the kinematic and thermodynamic structure of the eyewall of Hurricane Felix through analyzing the flight-level and dropsonde data in comparison with the data acquired from Hurricane Hugo in which the P3 aircraft experienced an extreme event as well. In the data analysis, the flight–level thermodynamic data error that is often caused by wetting of sensors is firstly corrected as part of quality-control. Flight-level data was plotted in a storm-relative framework, and vorticity and divergence were calculated to detect the presence of mesovortices in the eyewall of Hurricane Felix. The time evolution of pressure and wind were plotted to recognize trochoidal motion of the circulation centers. Furthermore, perturbations of wind velocities, pressure and vorticity were calculated to investigate coherent features in a similar manner as in the Hugo data analysis. Additional data such as that from dropwindsondes and the Stepped Frequency Microwave Radiometer were also analyzed. Results showed Hurricane Felix stronger peak winds perturbations in the inbound leg in contrast with the outbound leg. At around 16km of radial distance from eye of the inbound leg data showed a peak vorticity maximum. Similar to Hurricane Hugo, Hurricane Felix showed recognizable trochoidal motion.

Ramos-Garces, Fernanda

von Hillebrandt, Christa G. - Caribbean Tsunami Warning Program, NOAA National Weather Service

Geosciences

Assesing the importance of an effective meteotsunami warning system in the Caribbean

In recent years, Meteorological Tsunamis -meteotsunami- have attracted much attention to specialists in natural hazards due to their devastating sea level oscillations that impact coastal regions. Several destructive meteotsunamis have occured in various parts of the world’s oceans. This phenomenon is associated with atmospheric activity that causes strong tsunami waves. Comprehensive studies of meteotsunamis have found there is a necessity to take into account the threat of

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this natural hazard in existing marine warning systems. In the frame of this issue, the Caribbean Tsunami Warning Program -CTWP- located in Mayaguez, PR is committed to address the importance of such events in Puerto Rico and the Caribbean. In this ongoing project we are focusing on understanding the multi-resonant aspect of these types of waves by analyzing different case studies of recent meteotsunamis, with a particular focus on an event that occurred in June 2013 in New Jersey, USA. Our goal is to study the generation of this type of sea level oscillations in order to understand how warnings for this type of marine system should be issued for Puerto Rico and the Caribbean. As result, we are currently developing content on meteotsunamis for the website of the CTWP in order to efficiently support dissemination of the importance of such events. This has helped improve the commitment of the CTWP of providing education and preparedness services of tsunami observations for the general public, government, scientists and broadcast media.

192

Rivera-Lastra, Imaryarie

Lysa Chizmadia - Department of Geology, University of Puerto Rico Mayaguez Campus

Geosciences

A Petrographic Analysis of Igneous Rocks from Anguilla

This investigation is focused on a small outcrop of igneous rocks on the island of Anguilla. The purpose of this project is to study the nature of three samples and characterize them. This is important because they have not been studied in detail before. Then, they are going to be compared with rocks from nearby Saint Bartholomew and Saint Martin. The three islands are likely to share a geologic history and basement because of their proximity and bathymetry between them. The main hypothesis of this project is that these rocks are related to the extrusive igneous rocks from Saint Bartholomew and Saint Martin. It was confirmed that the samples from Anguilla are of igneous origin; they are probably a highly weathered basalt, porphyritic basalt and porphyritic andesite. Only one of the three samples 14AN-03 is probably related to both islands, St. Barths and St. Martin, because it is similar in composition and texture. The samples 14AN-01 and 14AN-02 is probably related only to St. Barths and reflects a lava flow that was exposed to water during its eruption.

193

Life Sciences

194

Acevedo-Cintron, Jesus

Acevedo, Jesús A. - Department of Biology, University of Puerto Rico, Río Piedras Campus; González-Nieves, Joel E. - Department of Biology, University of Puerto Rico, Río Piedras Campus; Colón-Sáez, José O.; Rosado, Irvin D. - Department of Biology, University of Puerto Rico, Río Piedras Campus; Quesada-González, Orestes - Department of Physical Sciences, University of Puerto Rico, Río Piedras Campus; Lasalde Dominicci, José A. - Department of Biology, University of Puerto Rico, Río Piedras Campus

Life Sciences

Crystallization studies of the nicotinic acetylcholine receptor (nAChR) using lipid analogue detergents and a modified lipidic matrix: Analysis of functionality and stability

The nicotinic Acetylcholine receptors (nAChR) are ligand-gated ion channels that are involved in fast chemical synapsis at the nervous system. Their involvement in several disorders such as Alzheimer, Parkinson and congenital myasthemic syndrome is well known. However, the X-ray structure of functional nAChR has not yet been solved. Our laboratory has focused on the use of phospholipid analog detergents for the purification and study of stability and functionality of nAChR isolated from the Torpedo californica. The stability of nAChR-detergent complex in the Lipidic Cubic Phase (LCP) was assessed by fluorescence recovery after photobleaching (FRAP) for a 30-day period, while functionality was measured using two electrode voltage clamp (TEVC). These biophysical parameters are essential to determine the appropriate conditions for functional nAChR crystallization. Our studies showed that nAChRs extraction is feasible by employing phospholipid analog detergents consisting of Foscholine (FC) head groups with 12, 14 and 16 carbon chains (FC-12, FC-14, FC-16), and the Ciclofos family with 4, 6 and 7 carbon chains. The functionality assays showed a mean amplitude of acetylcholine evoked currents using TEVC for FC detergent family behaves different in term of the acyl chain length. Moreover, the stability of nAChR-detergent complex using FC family showed longer acyl chains preserve a higher Mobile Fraction (MF) (approximately 90%). For the Ciclofos family, the MF values alternate from 0.30 to 0.70, and variability between days was also observed. The results demonstrate these detergents preserve a functional and stable nAChR-detergent complex that could be used for crystallization studies. NIH Grant: 1R01GM098343

195

Adorno-Carvajal, Natalia

Nuñez Pacheco, Wilfredo - Biology, Universidad de Puerto Rico, Recinto de Rio Piedras; Ospina, Oscar E. - Biology, Universidad de Puerto Rico, Recinto de Rio Piedras; Acevedo Charry, Orlando - Biology, Universidad de Puerto Rico, Recinto de Rio Piedras; Aboukheir, Mahmoud - Escuela de Salud Publica, Universidad de Puerto Rico; Burgos Rodriguez, Jhoset - Escuela de Derecho, Universidad de Puerto Rico; Ackerman, James - Biology, Universidad de Puerto Rico, Recinto de Rio Piedras

Life Sciences

The worm-lizards (Lepidosauria, Squamata, Amphisbaenidae) specimens housed in the Zoological Museum of the University of Puerto Rico at Río Piedras (MZUPRRP-R)

Zoological museums are facilities housing data-rich collections of different phyla of the Kingdom Animalia. These museums preserve species of different geographical areas and serve as repositories of reference specimens. This is particularly helpful when working with extinct or rare species or if it is difficult to identify them. Zoological museums also contribute significantly as educational centers for students and the general public. The Zoology of the University of Puerto Rico, Rio Piedras Campus MZUPRRP, was established in the 1960s by the naturalists Frank Rolle, Manuel Velez, and Harold Heatwole. The Herpetofauna is one of the prominent collections within the holdings of MZUPRRP. My work centered specifically on the Class Reptilia, Order Squamata, Family Agamidae, commonly known as worm-lizards. To organize the collection I used the phylogenetic classification by S. Blair Hedges and Laura L. Poilings 1999 work, A Molecular Phylogeny of Reptiles. According to Juan A. Rivero, the amphisbaenas are limbless, worm-like lizards found in Africa, Southeast Asia, and the Mediterranean countries, as well as the New World. Morphological characteristics of the head scales and the number of scale rings on the body were used to identify the species. According to the literature, the quantity of rings is regarded as the most reliable trait for identification. The specimen taxonomic classification, collection day, collector, collection code, location, among other information, was organized and inserted in a database using protocols of the Global Biodiversity Information Facility. GBIF provides open access via the internet. To georeference specimen localities we used Google Earth and the Global Information System platform, Quantum GIS. Preliminary results include collections from 1945 to 2008. Localities include Puerto Rico, British Virgin Islands, Haiti, and the Dominican Republic. Our holdings of Agamidae are represented by only one genus, Amphisbaena Agamidae, which includes 8 species n=220: A. caeca n=80, A. manni n=55, A. xera n=42, A. schmidti

196

n=35, A. innocens n=3, A. alba n=2, A. fenestra n=2, and A. bakeri n=1. The construction of this database will provide worldwide access, contributing significantly to branches of biodiversity, population ecology, taxonomy and systematics, among others.

Alvarez-Santos, Christian

Life Sciences

Clasificacion de la malacofauna en el bosque La Olimpia

This research worked with the diversity, distribution and abundance of the arboreal malacofauna at La Olimpia forest in the town of Adjuntas, Puerto Rico. This is the first scientific field work related with the identification of mollusks done in this community forest. The diversity of the gastropods was collected throughout different trails and plantations in this forest. We have identified species such as Pleurodonte caracola, Arcadia striata, Cepolis boriquenae, Bulimulus guadalupensis, and Succinea approximans. For every collected specimen we took length measurements. The distribution of the malacofauna was studied at different elevation and different plant communities such as trail “Pico Libertad”, “El Encanto”, and the orange plantation in the forest. A part from the distribution we took into account the trees species or substrate used by the mollusks. The abundance density and quantity was determined using quadrants along the trails and plantations at La Olimpia forest. A preliminary work with soil mollusks was done in different soil quadrants and structures, such as cement and wood structures present in this forest.

Andujar-Gonzalez, Lynnette

Dr. Armando Rodríguez- Durán

Life Sciences

197

Energetic cost of the caribbean islands endemic bat, Stenoderma rufum

It has proposed that islands bats have lower basal metabolic rates than their continental counterparts. The bat species studied, Stenoderma rufum, is an endemic frugivorous species of Puerto Rico. The objective of this research is to determine whether this species has a lower than expected metabolic rate based on its body mass. The method followed is the measurement of oxygen consumption by using the Sable Respirometry System. The measurements were made at 20 ° C, 25 ° C and 30 ° C. The individuals were caught in mist nets the night before each experiment. Our preliminary results suggest that the metabolism of Stenoderma rufum is lower than expected. The value obtained for oxygen consumption was 2.1534 ml/g/h, lower than the expected value according to Kleiber curve of 4.5359ml/g/h. This study contributes important information on energy adaptations of bats and other endothermic species on islands.

Aquino-Reynoso, Wilson

Bruno Marie - Institute of Neurobiology, UPR-Medical Science Campus

Life Sciences

RNA editing is involved in the temperature dependent synaptic growth at the Drosophila Neuromuscular Junction

Environmental changes can impact the nervous system of many organisms. We have observed that temperature positively regulates synaptic growth at the Drosophila Neuromuscular Junction (NMJ). Nevertheless, the molecular mechanisms that control this temperature dependent synaptic growth are still unclear. Here we study the role of the posttranscriptional regulation carried out by the ADAR (adenosine deaminase acting on RNA) enzyme. ADARs are responsible for RNA editing and as such can recode genetic information. They contain a double-stranded RNA (dsRNA) biding domain and an enzymatic domain (adenosine deaminase). To test the idea that RNA editing is essential to the temperature dependence of synaptic growth, we used transgenic Drosophila encoding for ADAR proteins showing different enzymatic properties. Adar5G1 (no ADAR enzyme) did not show the characteristic increase in synaptic growth at 30°C. AdarS (high editing activity) showed a slightly higher but significant growth at 30°C. AdarG (low editing activity) showed no response in growth with increasing

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temperature. These results suggest that ADAR’s RNA editing activity is playing a key role in temperature dependent synaptic growth at the NMJ, especially at high temperatures. Furthermore, our data suggest that the function of ADAR’s dsRNA biding domain (independent of RNA editing) is sufficient to disrupt the mechanisms that control temperature dependent synaptic growth.

Arroyo-Tarraza, Axel

Khaled Habiba - Department of Physics, University of Puerto Rico -Rio Piedras Campus, San Juan, PR, USA; Dina P. Bracho-Rincon - Department of Biology, University of Puerto Rico -Rio Piedras Campus, San Juan, PR, USA; Jose A. Gonzalez-Feliciano - Department of Biology, University of Puerto Rico -Rio Piedras Campus, San Juan, PR, USA; Carlos I. Gonzalez - Department of Biology, University of Puerto Rico -Rio Piedras Campus, San Juan, PR, USA; Javier Avalos - Department of Physics, University of Puerto Rico -Bayamon Campus, Bayamon, PR, USA; Gerardo Morell - Department of Physics, University of Puerto Rico -Rio Piedras Campus, San Juan, PR, USA

Life Sciences

Antibacterial Activity of Silver-Graphene Quantum Dots Nanocomposite against Gram-Positive and Gram-Negative Bacteria

The emergence of antibiotic-resistant bacteria is now a major threat to world-wide public health. Functionalized nanoparticles could offer novel strategies in this post-antibiotic era. In this study, we developed a nanocomposite of silver nanoparticles decorated with graphene quantum dots (Ag-GQDs) using pulsed laser synthesis. The nanocomposite was functionalized with polyethylene glycol (PEG), which may increase their cell uptake and solubility in aqueous solutions. The synthesized Ag-GQDs were characterized by UV–Visible spectroscopy, high-resolution transmission electron (HR-TEM) microscopy, Raman spectroscopy, X-ray diffraction (XRD) spectroscopy, field emission scanning electron (FE-SEM) microscope, energy dispersive spectrometry (EDS), X-ray photoelectron spectroscopy (XPS) and Fourier transform infra-red (FT-IR) spectroscopy. The biocompatibility of the synthesized Ag-GQDs was tested in HeLa cells using the cell viability assay. The antimicrobial activity of Ag-GQDs was evaluated against both Gram-negative Pseudomonas aeruginosa and Gram-positive Staphylococcus aureus bacteria. Their minimum inhibitory concentration (MIC) was determined and their antibacterial activity versus the time were assessed using the microdilution method.

199

In addition, their antimicrobial results were validated by the Kirby-Bauer disk diffusion method. We report that 150 µg/mL of Ag-GQDs exhibit strong antibacterial activity against both types of bacteria. Interestingly, this concentration is not toxic for human cells. Therefore our results suggest the use of the synthesized Ag-GQDs in the fabrication of self-sterile textiles, antibiotics, antibacterial coatings, and cosmetics.

Ayuso-Ruiz, Karla

Life Sciences

Control of bacteria in edible phyllosphere using commercial and home base vegetable washing solutions

The safety of horticultural produce for human consumption is an area of importance due to the increase effort to educate the population in healthy eating habits. The incidence of human pathogens in fresh fruit and vegetables has been a concern in industrialized countries in the last decade Brandl et. al. 2008. Consumers tend to prefer packed and processed lettuces under the impression that these products are safer than lettuces obtained directly from gardens and sometimes a proper management of the product is neglected. Previous studies on edible phyllosphere revealed presence of Staphylococcus sp. Cronobacter sakazaki and Xanthomonas maltophilia and Escherichia coli on processed lettuce and basic and safety measures, such as vegetable washing is necessary. The purpose of our study was to determine the controlling effect, if any of different treatments commercial vs home base solutions on edible phyllosphere Lactuca sativa var. longifolia. Lettuce samples were obtained from local supermarkets in the Humacao area. Initial quality and quantity analysis of lettuce samples was conducted using selective and differential media ENDO MSA Sorbitol MacConkey Sabouraud and TSA. Commercial and home base vegetable washing treatments were performed and quality and quantity analysis after treatment were repeated. Our study confirmed high density of bacteria on the original samples and immediate density reduction after all treatments. Home base treatments compare favorably with commercial treatments in controlling bacteria of lettuce.

200

Badwan-Musa, Osamah

Zbinden, Theodor - Biology, University of Puerto Rico - Humacao; Flores, Noelia - Biology, University of Puerto Rico - Humacao; Lozada, Tamia M. - Biology, University of Puerto Rico - Humacao; Nuñez, Dariana M. - Biology, University of Puerto Rico - Humacao; García-Arrarás, José - Biology, University of Puerto Rico - Río Piedras; Traverso, Edwin - Biology, University of Puerto Rico - Humacao

Life Sciences

Identification and Expression Analysis of Two Xenopus laevis Homologs of the Novel F-Box Containing Protein, FBXO30

Tumorhead (TH) is a maternal factor that regulates cell proliferation during early embryogenesis in Xenopus laevis. To understand how TH functions at the molecular level, we have been studying its relationship with the novel F-Box containing protein FBXO30, found in a two-hybrid screen for TH binding proteins. Using RT-PCR, we identified two FBXO30 homolog genes in X. laevis, named FBXO30-A and FBXO30-B. The FBXO30-A and FBXO30-B proteins share 64% and 63% identity with their Homo sapiens homolog, respectively. Sequence analysis and alignment of several vertebrate FBXO30 proteins show that they contain very conserved F-Box domains at their C-terminus, while the internal part of the proteins diverge extensively. We found through RT-PCR that FBXO30-A and FBXO30-B are maternal factors as their messages are present in the unfertilized egg. Their mRNAs persist during the cleavage stages but decrease dramatically once gastrulation starts. The FBXO30-A and FBXO30-B messages are present at low levels during organogenesis, showing a slight peak of expression during the mid-tailbud stages. In situ hybridization studies show that the maternal FBXO30-A mRNA is localized to the animal pole, and that the later expression of FBXO30-A occurs in the developing somites. Using antibodies raised against a synthetic FBXO30-A peptide, we have preliminarily localized the FBXO30-A protein to the nuclei of ectodermal cells at the gastrula (st. 12) stage. Our studies show the presence of two homologs of FBXO30 in X. laevis, which could be key regulators of early development, working with TH to regulate cell proliferation.

201

Baez-Bravo, Gabriela

Morales Lozada, Yermary - Chemistry, University of Puerto Rico- Río Piedras; Gómez Moreno, Ramón - Biochemistry, University of Puerto Rico- Medical Science Campus; Baerga Ortiz, Abel - Biochemistry, University of Puerto Rico- Medical Science Campus

Life Sciences

Isolation and Analysis of Outer Membrane Vesicles to Explore the Possible Transport Mechanism of the Genotoxic Compound Colibactin

Colibactin is a genotoxic compound found in strains of Escherichia coli that harbor the pks genomic island (pks island+). The pks island gene cluster has been found in fecal samples and it is highly correlated with colorectal cancer (Gómez Moreno et al., 2014). Diverse strategies to isolate colibactin from pks island+ strains have failed, and its transport mechanism remains unknown. Our laboratory is interested in exploring the possibility that colibactin may be accumulating in the periplasm between the inner and outer membranes and playing a role in the formation of outer membrane vesicles (OMVs). OMVs serve as an insoluble secretion pathway for gram-negative bacteria and are responsible for the release of outer membrane and periplasm out of the cell. These vesicles can travel far away from the cell and convey biological functions on to other cells. Hence, we believe that colibactin may be transferred to eukaryotic cells by means of this mechanism. The purpose of this project is to isolate OMVs from the pks island+ strain IHE3034 and two mutants: one with a deleted clbP gene and one that overexpresses the clbQ putative thioesterase. Both of these genes are presumed to be involved in colibactin biosynthesis. Once the OMVs are isolated, their chemical composition will be determined by GC/MS. We have already made the ?ClbP deletion mutant and we have successfully cloned ClbQ in an expression vector. Efforts are underway to isolate the OMVs released by these novel strains. These data are the first to address a possible transport mechanism for colibactin.

Báez-Cruz, Faviolla A.

202

Quesada, Orestes - Physical Sciences & Chemistry, UPR-Río Piedras; González, Carol - Chemistry, UPR-Río Piedras

Life Sciences

Possible Roll of Ion Gated Channel in the Mechanism of Action of the Myotoxic Phospholipase A2

A catalytically-inactive PLA2 variants having Lys instead of Asp at position 49, was initially discovered in the venom of Agkistrodon piscivorus piscivorus (App) but the number has increased in the Crotalidae snake family. This mutation drastically affects the ability of these PLA2 to bind the calcium ion required to stabilize the tetrahedral intermediary in the catalytic cycle. Despite the lack of an aspartate residue at position 49, K-49 PLA2 proteins are very active in the induction of myonecrosis by one or more, yet to be discovered, mechanisms. Our hypothetical mechanism involves the direct or indirect interaction of AppK-49 with a membrane ion channel in the neuromuscular junction. To test this possibility, a cell culture model of C2C12 mouse myotubes was used to assess the action of both isoforms of APP and a more catalytically active PLA2 from the elapid family, Naja nigricollis (Nn). The hydrolytic activity of these PLA2s was tested against the intact human erythrocyte and only NnD49 and AppD49 PLA2s displayed activity. Independent confocal microscopy assay with C2C12 myotubes treated with Alexa Fluor 488-conjugated to each PLA2s using, suggest that K49App interact merely on the plasma membrane of cell during the time course of the experiment. A cytolytic effect was induced by the D49PLA2s on C2C12 myotubes that can be explained in terms of plasma membrane perturbation which promotes a large increase of the cytosolic calcium ion. We used Alexa Fluor 555 conjugated to alpha-bungarotoxin to label the acetylcholine receptor (AChR) in C2C12 myotubes treated with Alexa Fluor 488-K49PLA2.

Barreto-Cordero, Yarelis

Borges, Gabriel - Garcia, Yaniel

Life Sciences

203

Determination of the Lowest Concentration of DES that Induce the Production of VTG Protein in Male Anolis Lizards

Humans throughout history have been exposed to a number of toxic substances, found naturally or made by their own hands. The exposure to toxic substances is detrimental not only for human health, but everything living in the habitat the toxic is present. Ways to detect the toxic before it causes problems is needed, meaning that they have to be detected while they are still in low quantities. The Anolis lizards have potential to be helpful in being a sentinel organism by detecting toxics that affect our endocrine system like xestrogenic agents (XE). Our research project consists of exposing the Anolis male lizards to low quantities of the estrogenic agent diethylstilbestrol (DES) and afterward detects the presence of the protein vitellogenin in their blood plasma. Males do not normally produce the vitellogenin protein; only sexually mature females produce it constantly. After the exposure to DES the lizard is sacrificed, the blood plasma proteins are analyzed with SDS-PAGE to detect if the bands representing vitellogenins are present. Our research was successful in confirming that the protein vitellogenin can be detected after exposing the organism to a concentration as low as 10ug of DES. Anolis lizards proved to be a potential sentinel organism for the detection of estrogenic agents at low concentrations.

204

Bauzó-Moreira, Ashley

Marcano, Maria Cristina - Biology, University of Puerto Rico Río Piedras; Acevedo Charry, Orlando - Biology, University of Puerto Rico Río Piedras; Aboukheir, Mahmoud - Escuela de Salud Publica, University of Puerto Rico; Burgos Rodriguez, Jhoset - Law school, University of Puerto Rico; Ackerman, James - Biology, University of Puerto Rico Río Piedras

Life Sciences

The Birds housed in the Zoological Museum of the University of Puerto Rico at Río Piedras (MZUPRRP-O)

Museums of natural history have aimed to discover and document the extensive biota of our planet through history. They are an important component because they register and identify our biodiversity and their changes. For this reason, museums in general are invaluable elements for our knowledge of life. Zoological museums not only identify and preserve species but they provide and facilitate the study of the different phenotypes and their changes, help monitor the health of species, and track their spatial distribution. Zoological museums have an important role in preserving extinct species or species in the verge of extinction. The Museum of Zoology of the University of Puerto Rico, Rio Piedras campus MZUPRRP is a repository of a wide variety of animals, mainly from Puerto Rico and the Caribbean. Drs. Frank Rolle, Manuel Velez and Harold Heatwole established MZUPRRP in the early 1960’s and collected and identified the majority of the specimens that are in the museum today. Since 2008, MZUPRRP has undergone resurgence in activity through reorganization and renovation. The museum currently contains approximately 70,000 specimens. The present work centered specifically on the collection of the avian specimens. Every species was classified phylogenetically following The American Ornithologists Union Checklist Of North And Middle American Birds and the identity of each specimen was verified using A Guide To The Birds Of Puerto Rico And The Virgin Islands. In addition, we geographically referenced each species using Google Maps and Quantuum GIS. Preliminary results indicate that the collection holds 367 bird specimens collected between 1937 and 2014. The majority of the specimens are from Puerto Rico and the Caribbean but there are various species that were collected in the United States, Central America, South America and India. Our database contains 41 families, 92 genera, and 128 species. The three most represented families are Parulidae n = 21 species, Emberizidae n = 14, and Icteridae n= 7. The three most represented genera are Setophaga n = 33, Quiscalus n = 14, and Tiaris n = 9. The MZUPRRP holds one specimen of the endemic Mariquita of Puerto Rico Agelauis xanthomos. This specimen has an extraordinary importance since the Mariquita of Puerto Rico

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is in verge of extinction. We will soon publish the database in the Global Biodiversity Information Facility, which is an international open data infrastructure that allows data to be shared internationally via the internet. Our goal is to provide accessibility of the avian collection digitally, which can be accessed for future research in avian systematics, biogeography, and ecology, or for practical purposes related to developing bird conservation and management strategies.

Belen-Silva, Dayanara

Acosta, Dimaris - Biology, Universidad de Puerto Rico- Recinto de Mayaguez; Acosta, Carlos - Biology.Universidad de Puerto Rico- Recinto de Mayaguez; Calderin, Bryan - Chemistry, Universidad de Puerto Rico-Recinto de Mayaguez

Life Sciences

The effect of climate change (precipitation) on the diversity of testate amoebae in three sites: Costa Rica, French Guyana and Puerto Rico

There is recent interest in understanding the effect of climatic change, particularly precipitation, on the diversity and composition of tropical trophic webs. One model suggested that some tropical forests would dry whereas other will over saturate. We don’t have enough data to predict the effects of such changes, not only in the biodiversity and nutrient cycling, but also on the dispersion of microbial- mediated diseases. In this project we will examine the diversity of testate amoebae as a model to predict the changes in the structure of the microbial trophic web. Given that testate amoebae are sensitive to humidity, we expect to find significant differences in species richness, abundance and species composition among treatments. A total of 33 bromeliads were assembled within mesocosms to avoid water entrance. Precipitation was simulated manually and added in a controlled manner. Normality and the non parametric t-test revealed that there were no significant differences in species richness and abundance between the pre sample and the post sample (precipitation simulated). In terms of composition, cosmopolitan species, like Trinema lineare, predominated because of their ability of adapting to different environments.

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Cabezas-Bou, Ernesto G.

Díaz-Ríos, Manuel E. - Department of Anatomy and Neurobiology, Institute of Neurobiology, University of Puerto Rico, Medical Sciences Campus

Life Sciences

Modulatory effects of taurine on locomotor behavior in the neonatal mouse spinal cord

Locomotion is a rhythmic behavior driven in mammals by a dynamic interaction between the periphera and central nervous system. Supraspinal centers including the brainstem and cortex send modulatory signals to neural circuits located within the lumbar spinal cord to activate, modulate and coordinate motor output in hindlimbs of animals by regulating muscle activity controlling flexion and extension. It has been shown that rhythmic locomotor activity (termed “fictive locomotion”) can be induced in an isolated preparation of a mouse spinal cord by the perfusion of serotonin, NMDA (a glutamate analog) and dopamine which imitate the type of supraspinal inputs that drive locomotion in the intact animal. In the Díaz-Ríos laboratory we are interested in the study of how natural and synthetic drugs affect locomotor behavior using the mouse isolated spinal cord preparation as our model system. Taurine, 2-aminoethylsulfonic acid, is one of the most abundant amino acids in the brain. It has various important physiological functions as a neuromodulator and antioxidant. Additionally, it has been shown to modulate chemical nociception in mammals. We are interested in looking at the possible modulatory effects of taurine when perfused directly to the mouse spinal cord. Since it has been shown that Taurine interacts with glutamate and Gamma-Aminobutyric acid (GABA) receptors and recent studies have shown that acute versus chronic administration of taurine can have contrasting effects in anxiety and locomotor activity. We hypothesize that changes in locomotor behavior, including output parameters such as ventral root recorded burst amplitude, burst duration and cycle period, could be stimulated or inhibited depending on concentration and time of exposure to taurine.

Cabrera-Molina, Gerardo

Hendricks, Timothy - Natural Sciences and Mathematics, Inter American University of Puerto Rico, Bayamon

207

Life Sciences

Disruption of Notch1 Signaling Pathway in Cultured Murine Primary Neurons

Notch1 is one of the four receptor proteins of the Notch signaling pathway that, when activated, undergoes proteolytic cleavage leading to a series of events which regulates cell fate decisions. Since high Notch1 activity has been shown in Neural Precursor Cells (NPC’s) we believe that Notch1 is involved in the process of the differentiation of dI6, a sub-population of commissural inhibitory interneurons which are an important component of the neural circuity that drives locomotion in mammals. The murine Notch1 gene sequence will be cloned into an expression vector (pReceiver) and modified to prevent cleavage of the intra-cellular domain (ICD) of the activated Notch1 receptor. The recombinant protein will be expressed in cultured neurons of mice spinal cord to address the hypothesis that Notch1 signaling regulates the differentiation of dI6 interneurons.

Calderon-Davila, Erik

Lynnete Andujar and Armando Rodriguez-Duran - Universidad Interamericana de Puerto Rico

Life Sciences

Energetics of the bat Brachyphylla cavernarum in Puerto Rico

There is evidence of many homeothermic species on island that show a reduced energy expenditure compared to continental species. An endemic gender of bat from the Caribbean, Brachyphylla cavernarum, was selected to measure its rate of metabolism. The consumption of oxygen was measured with a Sable System respirometry equipment at temperatures of 20, 26, 28, and 30ºC. Bats were captured in the same roost the day before the measurements. Food and water were provided until midnight and measurement began the following morning. Based on preliminary measurements of oxygen consumption of the bats, we estimated that the thermoneutral zone is at a temperature between 26-28 ° C. The higher or lower the ambient temperature will result in greater energy expenditure, therefore, the oxygen consumption is highest. These results also allow us to relate the preference of temperature at which they roost (about 26 ° C). This study contributes to the data base of research that seeks to verify energetic adaptation of homeothermic species on island.

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Cantero-Schaffer, Pablo

Joglar, Rafael - Department of Biology, University of Puerto Rico- Río Piedras Campus; Delgado, Peter - Department of Biology, University of Puerto Rico- Río Piedras Campus ; Alejandro, Michel - Department of Biology, University of Puerto Rico- Río Piedras Campus

Life Sciences

Current Stats and Distribution of Mountain Coquí (Eleutherodactylus portoricensis)

Amphibian populations are undergoing rapid decline due to environmental factors; these include, but are not limited to: global warming, habitat destruction, pollution, introduction of invasive species, and diseases such as chytridiomycosis, caused by the chytrid fungus Batrachochytrium dendrobatidis. During this research project we are studying the rapid decline in populations of Eleutherodactylus portoricensis, a species of tree frog endemic to the island of Puerto Rico. Historical distribution of E. portoricensis included the Central Mountain Range and the Luquillo Mountain Range. This stage of the project aimed towards pinpointing the locations where this species is currently found. Fieldwork was performed between 2013 and 2015; 83 localities of high elevation were visited in the Luquillo Mountain Range and Central Mountain Range. Eleutherodactylus portoricensis was found in seven of the 83 localities visited. These seven localities were limited to mountains of high elevations in El Yunque National Forest and Carite State Forest. For future endeavors, our research team plans to use historical data related to climatology and infection caused by B. dendrobatidis in order to better address the mayor factors contributing to E. portoricensis population decline and possible extirpation in parts of the island where this species was historically found. In conclusion, this project will serve as a blueprint to help maintain future populations of amphibians and create consciousness about the imminent threat of losing an important part of our biodiversity.

209

Cardona-Pena, Rene

Restrepo Carla - Biology; Colon Zuania - Biology

Life Sciences

Effect of temperature in the morphology at the 6th developmental stage of Eleutherodactylus coqui.

Temperature plays an essential role during the embryonic development of amphibians, affecting their morphology. Any change occurring early on the embryonic development can have lasting effects over the animal performance and its survival after hatching. Understanding factors that affect amphibian’s survival is crucial, since they are declining worldwide. Eleutherodactylus coqui is particularly vulnerable to changes in temperature during the 6th developmental stage. For this reason, our objective was to compare morphology on the 6th stage of development between three temperature treatments (20, 25 and 30C). We photographed incubated embryos at the selected stage of each treatment, and measured five morphological variables. Preliminary results showed that the time to reach the 6th stage varies with temperature, with time declining as temperature increases. Further results demonstrated significant size differences in the egg and yolk diameter, the head width, fore limbs length, but not in the hind limbs length. Our results reflect morphological changes between different temperatures and help us understand the magnitude of temperature effects during the 6th stage of E. coqui morphological development. Environmental changes that lead to rising temperatures can aggravate and perpetuate amphibian decline.

Carrion-Ortiz, Carlos

Gildea, John - Pathology, University of Virginia; Felder, Robin - Pathology, University of Virginia

Life Sciences

210

Micofluidics Cell Culture of Human Nephron Segments for the Analysis of Natriuresis as Regulated by Dopamine: A Pilot Study for the Treatment of Hypertension

In the United States, the leading cause of death is cardiovascular disease. Hypertension is the most expensive disease in the United States, generating over 69 million in treatment costs in 2008. Worldwide, from 2000 to 2025, it is predicted that 500 million people from low income areas will become hypertensive. Patients without hypertension have a ninety eight percent probability to reach the age of 70, while patients with hypertension, only have a fifty percent chance to reach the same age. Hypertension is associated with the decrease in the regulation of sodium balance by the kidney. In an attempt to find a novel method for the analysis of natriuresis, recent studies have been using the fabrication of enzymatically crosslinked microchannels made of gelatin for microfluidic cell culture. This gelatin structure mimics the physiological environment of a proximal convoluted tubule inside a nephron, for growing proximal convoluted tubule cells in the right geometry. This culturing process allows the measurement of sodium in each segment that is needed for the cells to start absorbing sodium from the bloodstream by modeling the natriuresis process using microfluidics. For the development of these channels, we used an inexpensive child shrink dink to make microchannels of the appropriate dimension in which to grow human kidney cells. With this study, we can define how much sodium is needed for the cells to absorb in the proximal convoluted tubule and establish a range of minimum quantity of sodium needed to start increasing the blood pressure.

Cedeño-Cedeno, Yessenia

Alfonso, Aixa Ph.D - Biological Sciences, University of Illinois at Chicago

Life Sciences

C. elegans hlh-3 mutant males have abnormal behavior in three specific mating-related steps

C. elegans have remarkable characteristics that facilitate the study of cellular differentiation and other developmental processes. The mating behavior of C. elegans males is complex and is characterized for having different sub-behaviors involved in the mating. The males possess elaborate structures like special tails, 87 sex-specific neurons and forty-one sex-specific muscles that provided the tools to

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perform a successful search of the hermaphrodite and then to effectively the copulation process. It is known that mutations in genes and sensory and mechanic circuits related to the components involved in this behavior cause abnormal mating in C. elegans. One of these mutations is hlh-3. Previous results in the laboratory demonstrated that C. elegans hlh-3 mutant males do not sire progeny. This, lead us to investigate the ‘leaving response”, the “premature spicule protraction”, and the “chemical attraction” to hermaphrodites in C. elegans males, all of these behaviors are important mating- related steps. We hypothesize that the C. elegans mutant males in strain AL155 will display some abnormal behaviors when compared to the wild type strain DR466. Preliminary results show that hlh-3 mutant males have abnormal leaving response and defects in the chemical attraction to the hermaphrodites. In addition, results for the premature spicule protraction assay shows that hlh-3 mutant males do not differ in the spicule position in comparison with the wild type. Our investigation will provide new insights in the control of the C. elegans mating behavior and help us understand how the protein encoded by hlh-3, a transcription factor does so.

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Cedeno-Rosario, Luis A.

Rodriguez-Velez, Ileana I. - Department of Chemistry, University of Puerto Rico-Humacao

Life Sciences

Cytotoxicity of Puerto Rican Endemic and Native Plants Extracts

Cancer is the second leading cause of death in the United States, being a certain death sentence to more than 570,000 people each year. Small molecules from natural sources and their derivatives are the most effective treatments currently available to combat the disease. Although plants have been historically target for anticancer drug discovery, the uniqueness and biodiversity of Puerto Rican flora represent an extraordinary opportunity to unravel the discovery of new secondary metabolites, especially from their endophytic microbial communities. Therefore, our first goal is to assess the cytotoxic profiles of native and endemic plant species in order to further investigate the potential existing in their endophytic microorganisms. In order to achieve this first goal, we collected a series of native and endemic plants, obtained their polar extracts (MeOH and water) and measured their cytotoxicity using the brine shrimp (Artemia salina) lethality test. Plants exhibiting activity in our preliminary assay (500 uM) are being further analyzed to determine the lethal concentration (LC50) of their extracts. Isolation of endophytic microorganisms from active plants is also in progress.

Chamorro-Ramos, Jose L.

Martinez-Casiano, Karla - Ponce Health Sciences University - Ponce Research Institute ; Ramos-Ortolaza, Dinah - Pontifical Catholic University of Puerto Rico at Ponce ; Torres-Reveron,Annelyn Ph.D. - Ponce Health Sciences University - Ponce Research Institute

Life Sciences

213

Morphine Withdrawal Reveals Sex Differences in Contextual Responses During Cued Fear Conditioning and Extinction

Drug abuse and addiction is different in males and females. In our previous experiments we found that withdrawal from chronic morphine produced a deficit in cued fear extinction learning only in male rats but not in females. We wanted to elucidate if sex differences were also evident for contextual fear responses. Males and females Sprague Dawley rats 60 days old were used. Female rats underwent ovariectomy surgery (OVX) prior to the behavioral experiments. Rats were injected either 0.9% saline or increasing doses of morphine for 5 consecutive days to induce dependence. At 14 and 84 hours somatic signs of morphine withdrawal were assessed after which rats were fear conditioned. Behavioral experiments consisted of three phases conditioning phase (three tone-shock pairings), extinction phase (12 tone alone presentations) and the test (two tone alone trials). To assess fear to the context we analyzed a 1-min pre-tone period before the tone cue occurred. We found that morphine treated males showed a tendency for increased freezing immediately upon exposure to the chamber on day 2. In our morphine treated OVX females we saw a very similar trend. On the contrary, we found that cycling females did not freeze significantly to the context independent of the treatment. This could suggest that in males and OVX females, withdrawal alters fear circuits independent of the withdrawal context, but when ovarian hormones are present, fear responses might depend on re exposure to the withdrawal context. Therefore, sex-differences in the course of withdrawal might alter contextual learning consequently relapse.

Claudio-Cintron, Marie

Bayala, Erick X. - Biology Department, UPR Humacao; Alejandro, Xiomarie, UPR Humacao - Biology Department, UPR Humacao; Casillas, Lilliam - Biology Department, UPR Humacao; Rodriguez, Ileana I. - Chemistry Department, UPR Humacao

Life Sciences

Screening of hypersaline extremophiles for new antimicrobial agents

There is a global health threat stirring in the microbial world. Strains of pathogenic, antibiotic-resistant bacteria are emerging, posing a challenge to medicine at a worldwide level. In addition, most Pharmaceutical industries have abandoned their

214

antibiotic research programs mainly due to their economic interests. In order to prevent what may become a health related catastrophe, it is imperative to expand our medicine chest of antibiotics. Puerto Rico is a paradise in terms of its biodiversity. Here we can find many types of ecological niches teeming with a great variety of microorganisms not available anywhere else, which could be potential sources for the development of new antibiotics. One of these microbiomes is home for extremophiles: the Cabo Rojo Salterns. In the summer of 2014, our group organized an expedition to the Salterns, where different areas -ponds, mats, and plants- were sampled and, as a result, we have generated a collection of ~100 microorganisms including bacteria, archaea and actinomycetes. Some of these bacterial isolates have shown antibiotic activity against Staphylococcus aureus and Pseudomonas aeruginosa. The morphological and genomic identification of isolates exhibiting antibiotic activity is in progress, as they will be further analyzed for the secondary metabolites they produce. In summary, the outcome of this research project will provide access to the identification of microorganisms from a widely unexplored ecological niche with the potential to produce new antibiotics.

Claudio-Gonzalez, Ricardo

Cruz Mendoza, Alberto Carlos - Departamento de Biologia, Universidad de Puerto Rico en Humacao; Concepcion, Mark Anthony - Departamento de Biologia, Universidad de Puerto Rico en Humacao; Medina, Henry - Departamento de Biologia, Universidad de Puerto Rico en Humacao; Torres, Lizbeth - Departamento de Biologia, Universidad de Puerto Rico en Humacao; Solis, Katherine - Departamento de Biologia, Universidad de Puerto Rico en Humacao; Velazquez, Iris - Departamento de Biologia, Universidad de Puerto Rico en Humacao

Life Sciences

Departamento de Biologia, Universidad de Puerto Rico en Humacao (Amazona vittata) to explore and maneuver for food location before field reintroduction

Each year, after the end of the reproductive season, young independent parrots are separated from their parents and are kept with other juveniles and older parrots in large flight cages. After closely monitoring these parrots, a sample is selected and is evaluated as potential subjects for field reintroduction. In this study, we present the results of a new phase of this PRE-RELEASE TRAINING. In this phase, parrots are being presented to a FORAGING APPARATUS designed to stimulate parrots to explore and to maneuver in order to get access to food. The results suggest that

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parrots were neophobic to the FA. Parrots to be released on 2015 will be exposed to the FA for a longer period of time. This sample consists of 24 parrots. Each trial consisted in two-hour observation periods made on the same day, prior to food provisioning. During the first hour of observation parrots were observed in the absence of a FA or other food sources. Every minute, after a signal given by a timer, the number of parrots in each of the four areas of the cage was annotated (60 time intervals). During the second hour, the same procedure was repeated, but in the presence of the FA. Currently, 0% of the parrots have learned to use the FA.This study is still in progress. Other foraging devices will be also evaluated on this sample prior to field reintroduction.

Colon-Carrion, Nicole

Lozada-Troche, Chad

Life Sciences

Endophytic fungi present in rice grains

Rice is one of the most important commercial crops worldwide. This grain represents around 75% of our daily diet. Crops and stored grains are susceptible to various pathogens that represent a threat to our health. The main goal of this study was to compare the endophytic fungi present o regular and Brown rice grains Results indicated that 10% of sterilized regular rice grains produce fungal growth while in brown rice was 44. An increase in fungal growth was observed in non-sterilized grains: 20% on regular grains and 56% in Brown rice. This variation may be due to differences in the processing methods used for each rice grain type. Pesticides and preservatives used for fungal growth control often reduce the number of endophytic fungi within the grains. A higher fungal diversity was found on regular rice grains, while on brown rice various species of Aspergillus and Penicillium were isolated. These genera include species that can produce powerful and dangerous micotoxins if grains are handle inappropiately.

Colon-Flores, Luis Gabriel

216

Pérez, Yamilette - Biology, UPR Rio Piedras; Washington, Anthony Valance - Biology, UPR Rio Piedras

Life Sciences

Identification of protein postranslational modification of TLT-1

Platelet activation is a key step of homeostasis. The activation leads to the expression of specifics molecules sequestered in platelet granules. Amongst these molecules we find the Triggering Receptor Expressed in Myeloid cells (TREM)-like-transcript (TLT-1). This protein is mainly found on megakaryocytes and platelets. It consists of a transmembrane domain and a cytoplasmic tail composed of both proline-rich region and an immune receptor tyrosine-based inhibitory motif. Current evidence suggests that TLT-1 play an important role in maintaining vascular hemostasis, regulating coagulation and inflammation at sites of injury, however TLT-1’s mechanism of action remains unknown. At this moment our purpose is to decipher the mechanism of action of TLT-1 in platelet activation. Like almost every protein, we believe that TLT-1 undergoes post-translational modifications once we activate the platelets with some agonists. We predict that one of these post-translational modifications it could be phosphorylation. Several techniques were used in order to sustain our hypothesis. Our western blot results show us different banding shift between active and resting platelets suggesting us that TLT-1 is undergoing some post-translation modification. The change in band by a change in molecular weight indicate to us that potentially several phosphate groups are added to TLT-1 upon platelet activation. Our aim is to detect and confirm in what part of TLT-1 sequence it has been phosphorylated using Mass Spectrophotometry technique and specific phosphor antibody. Knowing the mechanism of action of TLT-1 will help us understand better its role on platelet activation and coagulation.

Contes-De Jesus, Maytee

Rosenthal, Joshua J. - nstitute of Neurobiology, University of Puerto Rico, Medical Sciences Campus

Life Sciences

Improvements of site-directed RNA editing by using RNA editing enzymes from different organisms.

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Genetic mutations can be corrected at the RNA level through the process of RNA editing. This process is carried out by diverse families of enzymes which act through varying mechanisms. One family is the adenosine deaminases that act on RNA (ADARs). ADARs catalyze the hydrolytic deamination of an adenosine residue to an inosine, which is read as a guanosine during translation of mRNA. This change in the mRNA sequence can result in recoding codons, and thus can change protein function. A recombinant version of human ADAR 2 has been previously engineered so that it can be directed to specific adenosines in mRNA and edit them with 100% efficiency in vitro. However, when tested in celula using transfected HEK293 T cells, the efficiency of correction was only 12%. To optimize this strategy, we are testing the editing efficiency of deaminase domains from nine different organisms in HEK293 T cells and specifically comparing them to human ADAR2. We hypothesize that deaminase domains from different organisms may be individually tailored to edit adenosines in different contexts and therefore could prove useful in the correction of specific genetic mutations.

Crespo-Velez, Daniel

Lopez-Lloreda, Daniel - Biology Department, University of Puerto Rico Rio Piedras Campus; Garcia-Arraras, Jose - Biology Department, University of Puerto Rico Rio Piedras Campus

Life Sciences

Effect of reverse transcriptase inhibition in the regeneration of the sea cucumber radial organ

Retroelements present a novel focus in post-traumatic regeneration studies. Retrotransposons have been shown to be differentially expressed during the process of central nervous system regeneration in the sea cucumber. The role of these mobile genomic elements remains to be studied during this process. Reverse transcriptase inhibitors are a possible tool to analyze the inhibition of retroelement transposition within the genome, and therefore how this inhibition affects regeneration. Regeneration of the radial nerve cord, main component of the sea cucumber central nervous system, was studied after reverse transcriptase inhibition following injury. Staining of ?-GFS, ?-Phalloidin, and RN1 of the radial organ, mainly radial nerve cord and longitudinal muscle did not show any clear differences between untreated and treated animals. However, treated radial nerve cord seems to have fewer cells than untreated animals. Furthermore, observations of the circular muscle suggest that there are more cells with elongated nucleus and

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muscle regeneration seems to be impaired. Differences in cell number and morphology may give insight into the role of retrotransposons in nervous regeneration. Funded by NIH, NSF & University of Puerto Rico

Cruz-Abreu, Daniela

Louime,Clifford - Natural Science, UPR-Rio Piedras

Life Sciences

Global Climate Change - A Threat to U.S. National Security

In a recently published report, the US Department of Defense (DOD) identified global climate change as one of the major challenges currently faced by the US Military. Threats, brought about by climate change, such as infectious diseases and terrorism will impact national security by exacerbating current military challenges. These future trends capable of negatively impacting military operations call for a new strategic blueprint which factor climate impacts into defense scenarios. Adaptation and mitigation strategies will be implemented not only to reduce greenhouse gas emissions but also to address current and future changes. Among these strategies, is our current research initiative focusing on Algal Biofuels funded by the DOD CREST Center for Renewable Energy and Sustainability. The main goal of this project is to develop superior marine microalgae strains, demonstrating enhanced productivity metrics for outdoors deployment. This process will involve a thorough bioprospecting of Puerto-Rico marine ecosystems. Ultimately, we are proposing to engineer commercially acceptable capabilities into a viable production strain with a focus on tropical (assuming higher photosynthetic activity) marine (freshwater limiting resource) microalgae.

Cruz-Arzon, José A.

Ucker, David S. - Department of Microbiology and Immunology, College of Medicine, University of Illinois at Chicago

219

Life Sciences

Surface Expression of Enolase on Pathogenic Bacteria Mimics Apoptotic Cells and Elicits Immunosuppression

Enolase, which is an intracellular enzyme in viable mammalian cells, becomes externalized uniquely on the surface of apoptotic cells. Surface-exposed enolase is believed to be a recognition determinant involved in eliciting immunomodulatory functions characteristic of apoptotic cells. Among those immunosuppressive responses are the transcriptional induction of anti-inflammatory cytokine genes, such as IL-10, and the transcriptional repression of pro-inflammatory cytokine genes, such as TNF-?. The induction of IL-10, which is an immediate-early response to apoptotic cells, represents a particularly distinctive apoptotic signature. Some pathogenic bacteria, such as Streptococcus pyogenes and Listeria monocytogenes, express enolase on their surfaces, suggesting that they might mimic the immunosuppressive activity of apoptotic cells to enhance their pathogenicity. This hypothesis was explored directly by examining the ability of pathogenic bacteria to elicit anti-inflammatory transcriptional responses attributable normally to apoptotic cells. RNA was isolated from macrophages that had been cultured with pathogenic bacteria. Transcripts were analyzed quantitatively by qPCR analysis. The results demonstrate that surface enolase-positive pathogenic bacteria do modulate immune responses in mammalian cells, and that they specifically mimic apoptotic cells with regard to the inhibition of pro-inflammatory cytokine, TNF-?, gene transcription and the induction of anti-inflammatory cytokine, IL-10, gene transcription. These studies provide evidence for the involvement of apoptotic mimicry as a potential strategy in bacterial pathogenesis. Elucidation of the specific function of enolase on the surface of pathogenic bacteria in this immunomodulatory role may contribute to future understanding of immunological diseases involving apoptotic modulation.

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Cruz-Castro, Stephanie

Sherylee Sanchez - University of Puerto Rico-Rio Piedras, San Juan, PR 00931; Eric V. Stabb - University of Georgia Athens, Athens, GA, 30602; Zomary Flores- Cruz - University of Puerto Rico-Rio Piedras, San Juan, PR 00931

Life Sciences

The Effect of Peroxidase in the Bioluminescence of Vibrio fischeri

Vibrio fischeri is a bioluminescent marine Gram- negative bacterium, found in sub-tropical waters free-living or in a mutualistic relationship with the squid Euprymna scolopes. The squid’s light organ supports V.fischeri growth, while it provides an anti-predatory benefit to the squid. The light organ produces reactive oxygen species in response to bacteria, however V. fischeri must have the capacity to overcome this oxidative stress in order to colonize it. Therefore, several experiments were performed to test whether the peroxidase, AhpC, or catalase, KatA, are responsible for oxidative stress resistance in V.fischeri. An AhpC mutant and an AhpC/KatA double mutant were generated and later exposed to the superoxide generator methyl viologen to observe its effect on growth and bioluminescence. In culture, all the strains grow equally however; the double mutant is significantly brighter than the other strains. When the strains were exposed to methyl viologen, the wild-type and the KatA single mutant grew faster than the strains lacking AhpC. The bioluminescence of the wild-type and KatA strains was reduced. However; the AhpC and AhpC/KatA mutants’ bioluminescence was not affected. These results suggest that AhpC is necessary for methyl viologen tolerance and that in the absence of AhpC the oxidative stress induces bioluminescence. For future work includes quantifying oxidative stress in AhpC mutant strains.

Elvir-Ramos, Lillian K.

Acevedo Charry, Orlando; Kelly, Sean; Aboukheir, Mahmoud - Escuela Salud Pública, Universidad de Puerto Rico; Burgos Rodríguez. Jhoset - Escuela de Derecho, Universidad de Puerto Rico; Ackerman, James - Biology, Universidad de Puerto Rico Rio Piedras

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Life Sciences

The Araneidae (Araneae, Arachnida, Chelicerata) housed in the Zoological Museum of the University of Puerto Rico at Rio Piedras (MZUPRRP)

Museums are places that keep and preserve collections of different kinds for the use and needs of the community. There might be museums for exhibition, education or investigation. A zoology museum stores different specimens of all kinds of animals, which also means that they are arranged according to their taxonomic group. The Museum of Zoology of the University of Puerto Rico, Río Piedras Campus better known in Spanish as Museo de Zoologia UPRRP (MZUPRRP) is composed of specimens collected by researchers for a wide variety of projects. The MZUPRRP consists of approximately 70,000 specimens preserved either dry or in alcohol. The earliest collections are specimens from the 1930’s and new ones are added throughout the year. Some of the biggest collections are the Mollusca, Crustacea, Chelicerata, and Reptilia. The museum serves the University community by offering workshops to Zoology students and the use of the specimens for investigation; and to the community in general by offering tours and workshops to school students or interested groups. The Chelicerate collection is classified and organized phylogenetically based on the most recent phylogenies. Families are temporarily organized in alphabetic order until a more classification is published. The specimens are mostly determined by their collector or by an identifier. The Families Agelenidae, Amaurobiidae, Anyphaenidae and Araneidae from the Order Araneae are being added to a database using the Global Biodiversity Information Facility (GBIF) protocols. All the specimens in the database are georeferenced to obtain a full-scale picture of where these organisms have been found. Our database currently contains 4 families, 21 genera and 38 species. When uploaded to GBIF database the collection will be accessible worldwide for a broad spectrum of basic and applied research projects related to the evolution, ecology, systematics and public welfare.

Feliciano-Robles, Waldemar

Erik Calderón-Dávila - Universidad Interamericana de Puerto Rico, Recinto de Bayamón; Armando Rodríguez-Durán - Universidad Interamericana de Puerto Rico, Recinto de Bayamón

Life Sciences

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Impacto del desarrollo urbano y la fragmentación de habitáculos sobre las poblaciones de murciélagos en Puerto Rico

En Puerto Rico el siglo 20 se caracterizó por una fuerte deforestación, seguida por desarrollo de bosques de crecimiento secundario. Se midió la abundancia relativa, riqueza y diversidad de especies de murciélagos en tres localidades situadas en los pueblos de Manatí, Ciales y Bayamón, Puerto Rico. Como parte de la metodología se midió el porcentaje de zonas con desarrollo urbano dentro de un radio de 5km, se capturáron con redes de niebla dos veces al mes en cada localidad y se complementaron las capturas con monitoreo acústico. Se marcaron algunas especies con “VI Alpha tags” subcutáneos en el antebrazo. Hasta la fecha las especies más abundantes son: A. jamaicensis en Ciales, Erophyllas bombifrons en Manatí y Monophyllus redmani en Bayamón. En Ciales se han capturado 61% de las 13 especies que habitan en Puerto Rico, 31% en Manatí y un 77% en la localidad de Bayamón. El índice de diversidad en la localidad de Ciales es de Hs=1.57, en Manatí de Hs=0.95 y en la localidad de Bayamón es de Hs=1.39. Hemos capturado hasta el momento 384 individuos para la localidad en Ciales, 41 individuos en Manatí y 284 individuos en Bayamón. Esta diferencia de individuos capturados puede estar asociada a la escasez de recursos, proximidad a cuevas y/o al efecto isla. Estos resultados señalan la importancia de conservar áreas naturales íntegras; pero también apuntan a la importancia de los parchos dentro de nuestros ecosistemas, debido a que juntos pueden representar una gran fuente de recursos para los murciélagos.

Fernandez-Gonzalez, Jean Carlos

Cindy M. Figueroa - chemistry, uprrp; Moraima Morales-Cruz - Biology, uprrp; Kai Griebenow - Biochemistry, uprrp

Life Sciences

Construction of targeted delivery system based on Hyaluronic Acid and Cytochrome c for cancer treatment

Cancer treatments like chemotherapy are problematic, because of devastating toxic side effects. To asses this problem, we developed a targeted and cytotoxic drug delivery system composed of Cytochrome c Cyt c and hyaluronic acid HA. The apoptotic protein Cyt-c was modified with HA to provide higher circulation time, biocompatibility, amphiphilic character, and passive targeting ability. Also HA was

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used as an active ligand, since its receptor CD44 has been found overexpressed in certain cancers. Bioconjugates were prepared using low and high molecular weight HA 8293 Da and 1.8x106 Da and Cyt c through physical interactions. Characterization of the bioconjugates included CD and UV spectroscopy. Results for absorption spectra showed changes in Cyt c absorbance intensity around 280 nm, suggesting protein modification with the polymer. CD spectra suggest slight changes in protein tertiary structure and no alteration of heme group, active site, during modification. To test Cyt c-HA performance, cell viability assays were carried out. HeLa and A549 cells were used as cancer CD44-positive cell lines. NIH-3T3 and Huvec cells were used as normal CD44-negative cell lines. After 24 hours of incubation with the bioconjugate 0.15 mg/ml, HeLa and A549 cells showed significant reduction in cell viability. In contrast, NIH-3T3 and Huvec cells viability was not affected by the bioconjugates. Cellular uptake and death were observed using confocal microscopy, confirming cytotoxicity of the system and specific internalization into cancer cells. Results indicate that Cyt c-HA is a targeted delivery system and must be considered as a promising cancer therapeutic.

Fernandez-Martinez, Mariceli

Edwin Vazquez - Howard Hughes Research Experiences for Teachers Program ,Biology Department, UPR-Cayey P.O. Box 372230, Cayey, Puerto Rico 00737; Michael Rubin - Howard Hughes Research Experiences for Teachers Program ,Biology Department, UPR-Cayey P.O. Box 372230, Cayey, Puerto Rico 00737; Eduardo J. Correa-Vazquez - Howard Hughes Research Experiences for Teachers Program ,Biology Department, UPR-Cayey P.O. Box 372230, Cayey, Puerto Rico 00737; Arelys Flores-Vazquez - Howard Hughes Research Experiences for Teachers Program ,Biology Department, UPR-Cayey P.O. Box 372230, Cayey, Puerto Rico 00737; Joseph Joseph Perez-Otero - Howard Hughes Research Experiences for Teachers Program ,Biology Department, UPR-Cayey P.O. Box 372230, Cayey, Puerto Rico 00737; Myrielis Rivera-Burgos - Howard Hughes Research Experiences for Teachers Program ,Biology Department, UPR-Cayey P.O. Box 372230, Cayey, Puerto Rico 00737

Life Sciences

Characterization and Identification of Bacteria Isolated from Tropical Ecosystems

Each year, approximately sixteen future science teachers participate in original research projects to characterize bacteria isolated from diverse ecosystems of

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Puerto Rico. Defining the diversity of bacteria is important for microbial community analysis, evolutionary studies, novel gene identification, and discovery of economically important metabolic activities. Bacteria were isolated and purified on nutrient and selective media from environmental samples. After cryogenic freezing, these bacteria were characterized and identified using colony morphology, gram staining, and sequence determination followed by bioinformatics analyses of PCR products amplified from genomic DNA using 16S ribosomal RNA (rRNA) specific primers. Isolated bacteria were screened for diverse metabolic activities including petroleum degradation, antibiotic production and resistance, and cellulase production. Bioinformatics analyses of 16S rRNA amplified PCR products identified bacteria belonging to genera comprising diverse taxonomic groups including Acinetobacter, Bacillus, Burkholderia, Comamonas, Dyadobacter, Enterobacter, Lysinibacillus, Lysobacter, Pseudomonas, Silanimonas, Staphylococcus, Stenotrophomonas, Streptomyces, and Veillonella. Bacteria capable of metabolic activities including petroleum degradation and antibiotic production were identified and are currently being analyzed. Characterization of these cultivation-dependent environmental isolates and their metabolic potential furthers our understanding of the composition and activities of tropical microbial communities. This project provides an opportunity for many undergraduate students to participate in original research experiences enriching their understanding of theoretical and experimental biology. The Howard Hughes Medical Institute and UPR-Cayey support this research.

Ferrer-Del Busto, Maria

Quesada, Orestes - Physical Sciences, UPR-Rio Piedras; Fernandez, Emily - Biology, UPR-Rio Piedras; Gonzalez, Carol - Chemistry, UPR-Rio Piedras; Colon, Jose - Biology, UPR-Rio Piedras; Lasalde, Jose - Chemistry, UPR-Rio Piedras

Life Sciences

Nicotinic Acetylcholine Receptor from Torpedo californica Electric Organ: Bulk and Annular Lipid Composition

Nicotinic acetylcholine receptors (nAChRs) play many critical roles in brain and body function and have been implicated in a number of neurological, including Alzheimer and Parkinson diseases and psychiatric disorders, including nicotine dependence. The nAChRs are prototypical members of the ligand-gated ion channel superfamily of neurotransmitter receptors. The X-ray structure of AChR has not yet been solved since its hydrophobic character hampers its successful

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crystallization. nAChRs is in intimate contact with the annular lipids in its native membrane and its stability and functionally depend on the lipid environments. In order to obtain a functional nAChR for future X-ray studies, a detergent that mimic the native environment of the receptor it’s essential. The main goal of this study was to determine the bulk lipid composition of the Torpedo californica (Tc) electric organ, a rich source of muscle-type nAChR for further detergents selection. To address this, the efficacy of two different extraction protocols (Folch and Bligh & Dyer) was evaluated against the Tc electric organ. We performed lipid analysis using gas chromatography mass spectrometry (GC/MS) to characterize the presence of fatty acid, and Ultra Performance Liquid Chromatography-Mass Spectrometry (UPLC-MS) to identify the phospholipids molecular species. The amount of lipids extracted from the same amount of tissue from Tc electric organ differ in favor of the Bligh & Dyer method. The percent of lipid recovery from the Tc electric organ were 15.79 and 20.14 for the Folch and Bligh & Dyer methods respectively (p < 0.0001). The dominant saturated fatty acid for both extraction methods under acid catalyzed hydrolysis were the palmitic acid (16:0) and stearic (18:0). Four different monoenes species were found in the Tc tissue, being docosahexaenoic acid DHA, 22:6 n-3 the most abundant polyunsaturated fatty acids. We performed lipid analysis of the detergent-solubilized nAChR using two lipid-like detergents, lysofoscholine-12 (LFC-12) and lysofoscholine-16 (LFC-16). Also, we measured the channel activity of the Tc nAChR-detergent complex incorporated into the Xenopus leavis oocytes membrane using voltage clamp technique. The activity of these nAChR-detergent complex and crude membrane microinjected into the oocytes rapidly incorporated into the plasma membrane. Currents was elicited 24 hr after the injection. Results showed a remarkable difference in activity in favor of the LFC-16 -446 nA vs -12 nA for the LFC12, this result was expected due the abundance of 16:0 fatty acid in the native Tc lipids. This work was supported by NIH UPR-MARC Program Grant Number 5T34GM007821-35.

Figueroa-Merced, Diane

Figueroa Merced, Diane E. - Ciencias Naturales y Tecnologia, Universidad del Turabo; Pérez-Jiménez, José R. - Ciencias Naturales y Tecnologia, Universidad del Turabo

Life Sciences

Antimicrobial activity in urban soils

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Antimicrobial activity is commonly found in nature as a defense mechanism for many bacteria. Nowadays, antimicrobial alternatives have become limited for the pharmaceutical industry and health providers due to increasing emergence of antibiotic resistance capabilities. Our objective is to characterize soil bacteria capable of inhibiting bacterial concurrent growth. Soil samples were collected from urban areas in Eastern Puerto Rico. Samples were diluted in saline solution and cultivated in Tryptic Soy Agar and Actinomyces Isolation Agar for a week at room temperature. Growth was examined daily for evolution of inhibition zones and isolation of participant bacteria. Bacterial isolates have been partially characterized based on Gram stain and catalase production. Antimicrobial activity was tested in concurrent cultures of isolates with reference strains in agar plates. Most of the isolates were spore-forming Gram-positive rods, and catalase positives. Among them, six strains demonstrated antimicrobial effect against Acinetobacter baylyi, Bacillus subtilis, Enterobacter aerogenes, Escherichia coli, and Staphylococcus epedermis. We are in the process of completing characterization of isolates by 16 rDNA sequencing. Additonally, growth curves will be conducted to determine in which stager the antimicrobial metabolite is produced for further biochemical characterization.

Flores-Siaca, Ian

Melendez, Elvia - Environmental Science, University of Puerto Rico Rio Piedras Campus

Life Sciences

Potential plant resources for nectarivorous bats in urban areas.

Bats are main pollinators of many tropical plants. Many of these plants have coevolved with bats so that their patterns of flowering phenology and flower morphology discourage diurnal pollinators while favoring bat visitation. Interest in the role of urban areas as places to be used to for biodiversity conservation is increasing. From the perspective of bat conservation, studying the use of green areas and plant resources by bats is a first step towards the design of bat conservation strategies that integrate urban areas. Here I present, a proposal to study plant-bat pollination interactions in the San Juan Metropolitan area that evaluates which canopy species recorded for this area exhibit a chiropterophillic pollination syndrome and of those which ones are actually being visited by bats. The study first evaluates published information of the tree biodiversity of this urban site to determine which species area most likely to be visited by bats and where

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they might be located. Then couples this information with field observation s of bat flower visitation, field measurements of plant characteristics and pollen diversity deposited on bats. Aside from the ecological information about plant-bat interactions in urban areas, this information may be useful in the design of urban landscapes that are bat friendly.

Garayalde-Batista, Zorimar

Garayalde-Batista, Zorimar M. - Science and Technology, Universidad Metropolitana; Marquez, Keishla - Science and Technology, Universidad Metropolitana; Gómez-Garzón, Diana - Science and Technology, Universidad Metropolitana

Life Sciences

DOWN-REGULATION OF STAT3 BY AZT TREATMENT

STAT (Signal Transducer and activators of transcription) is a family that has the ability to be a transcription factor in the nucleolus and a signal transducer in the cytoplasm. This family has unique structural domains where a tyrosine becomes phosphorylated cytosine-stimulated cells, like the Janus kinases. This family regulates numerous genes in different developmental stages of the organism. If STAT members are missing or wrongly expressed, it could cause numerous diseases and syndromes. Is composed of 7 members STAT1, STAT2, STAT3, STAT4, STAT5A, STAT5B and STAT6, which mediate the response to cytokines and growth factors. The purpose of our study is to determine in vitro expression pattern for the gene STAT3 using CEMss cells cultures treated with AZT (Azidothymidine) antiviral drug. Initially, we optimized conditions and perform standard curve validation with greater efficiencies to 98% and R2 of 0.946 for S15 housekeeping gene as internal reference and STAT3 gene. The melting curve for relative expression of S15 resulted with a Tm 86.9°C and STAT3 with 79.6°C. Finally, analysis for STAT3 was performed the Relative Quantification and Comparative Ct (??Ct) real-time RT-PCR at the conditions previously optimized. As a result, after treatment with AZT the STAT3 gene remained down-regulated from 1 day (fold change -0.6) to 10 days trial (fold change -1.3). This suggests that down-regulation of STAT3 gene expression by AZT and this gene should be evaluated as a potential biomarker such as it is involved in resistance to anticancer drugs.

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Garcia-Sanchez, Lyanne

Colón, Jennifer M. - Dept. Physiology and Biophysics, UPR School of Medicine; Cajigas, Ámbar - Biology Dept., UPR Rio Piedras; Torrado, Aranza - Dept. Physiology and Biophysics, UPR School of Medicine; Salgado, Iris K. - Dept. Physiology and Biophysics, UPR School of Medicine; Santiago, José M. - Dept. Natural Sciences, UPR Carolina; Miranda, Jorge D. - Dept. Physiology and Biophysics, UPR School of Medicine

Life Sciences

ESTRADIOL ADMINISTRATION AFTER SPINAL CORD INJURY ENHANCES WHITE MATTER SPARRING

Spinal cord injury SCI triggers a variety of events at the cellular and molecular levels, such as apoptosis, demyelination, inflammation and gliosis, generating a non-permissive environment for axonal regeneration and cell survival. Studies suggest that Estradiol E2 promotes neuroprotection by suppressing some of these negative events but its effects are debatable. This study aims to assess the effect of E2, as a multiactive hormone after SCI. Adult female Sprague-Dawley rats received a moderate contusion at the thoracic vertebrae 10 with the NYU impactor device and then silastic tubes with 3mg estradiol were implanted. Behavioral studies BBB and grid walking tests were performed weekly over 35 days post-injury. Luxol fast blue studies were accomplished to assess white matter spared tissue. Although no behavioral recovery was observed, animals treated with E2 immediately after SCI had a significant increase in white matter spared tissue p<0.05. To address the possibility that E2 was not able to reach the lesion epicenter fast enough to block adverse events and promote behavioral recovery, another group of injured animals were also injected with a bolus of 100 µg E2 immediately after SCI. Behavioral results showed no significant difference in functional locomotor recovery between groups. Interestingly, the group treated with E2 by injection and silastic tubing showed significantly more white matter spare tissue. This suggests that E2 administration may have a neuroprotective role after the injury that can enhance neuronal survival and/or myelination although the effect is not sufficient to improve functional locomotor recovery.

Gomez-Rivera, Francisco

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Raphael, Itay - Department of Biology, University of Texas at San Antonio, San Antonio, Texas; Forsthuber, Thomas - Department of Biology, University of Texas at San Antonio, San Antonio, Texas

Life Sciences

A Novel Mouse Model to Study Chronic-Progressive Multiple Sclerosis

Multiple sclerosis (MS) is an inflammatory autoimmune disorder affecting the central nervous system (CNS) which affects over 400,000 Americans and over 2.5 million people worldwide. Although most patients are initially diagnosed with relapsing-remitting MS, the majority of these patients later develop a chronic-progressive form of MS, for which there is no well-established mouse model. The most common genetic factors associated with genetic susceptibility to MS are the Human Leukocyte Antigen (HLA) genes which reside within the major histocompatibility gene complex (MHC), particularly in the HLA-DR2b haplotype. Additionally, tumor necrosis factor alpha (TNF) signaling through the TNFR2 receptor has been shown to have an important role in the remyelination process and mice, deficient for TNFR2 have been shown to have increased disease severity. The aim of this project is to evaluate TNFR2-/- mice, transgenic for the MS associated HLA-DR2b haplotype, for their potential use as a model for chronic-progressive MS. Our data indicates that the disease observed in HLA-DR2b+/+ TNFR2-/- mice closely mimics the pathology and clinical phenotype observed in chronic-progressive MS. Currently we are further investigating the mechanisms that contribute to the disease phenotype in these mice. Thus, HLA-DR2b+/+ TNFR2-/- mice can be used to study chronic-progressive MS and elucidate some of the mechanisms which are involved in the pathology of this disease.

Gonzalez-Irizarry, Yomarie

Life Sciences

Molecular cloning of Gm5595

A dorsoventral neural cells population, the V0 cells, are a commissural inhibitory interneurons located in the spinal cord. These cells are an important component of the locomotor circuitry, whose function is the coordination of left-right alteration.

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Regardless of this, this population of cells doesn’t have a specific marker. To resolve this limitation the gene Gm5595 will be studied since in a recent microarray, it appeared expressed in the neural tube during neurogenesis. We proposed to clone Gm5595 for the purpose of studying its mRNA expression. Currently a fragment of the gene has been amplified and cut using two restriction enzymes; EcoRI and KpnI. This fragment then will be ligated to the vector pUC19 to be inserted into the bacteria E. coli. The future goal of this project is to find how the function is affected and find if the gene is expressed in V0 population. The importance of Gm5595 is that if it's found to be a molecular marker, it can be used to identify V0 population, a population with no known reliable post-mitotic markers. Therefore, this gene has become a potential marker of the V0 population.

Gonzalez-Rosario, Karleen

Karleen M Gonzalez Rosario - Ciencias y Tecnologia, Universidad del Turabo

Life Sciences

Spatial heterogeneity of soil microbial communities in El Verde, El Yunque National Forest.

The soil is composed of minerals, organic matter, air, water and microorganisms. The plants and animals that grow and die in/on the soil are decomposed by microorganism and transformed into organic matter that is mixed with soil. The Canopy Trimming Experiment located at El Verde in El Yunque National Forest intends to understand the effects of a hurricane in a tropical forest ecosystem. Understanding the changes of the microbial community in of the soil can help us understand how ecosystems recover after a disturbance. The objective of this research is to determine if there is spatial heterogeneity between microbial communities of the soil (between blocks and between plots of the same block). The microorganisms studied in this research are bacteria and fungi. The molecular technique used in this research to study and compare these microorganisms is the TRFLP technique. According to the results obtained we found the presence of spatial heterogeneity between microbial communities (bacterial vs. fungi) of the soil. We observed that some of the bacterial communities were grouped by blocks or plot, which may mean that there is homogeneity among those samples. Taxonomically, bacteria tend to have more similarity. We discover in fungi that there is no homogeneity, only exists heterogeneity between samples. In conclusion, using the results we determine and demonstrate the existence of spatial heterogeneity

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between sub-plots. In the future, we will analyzed the effect of a hurricane on the structure of soil microbial communities.

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Haddock III-Soto, Luis A

Colon-Morales, Edgardo - University of Puerto Rico, Rio Piedras Campus; Lasalde, Clarivel - University of Puerto Rico, Bayamon; Lin, Qishan - Center for Functional Genomics, University at Albany; Gonzalez, Carlos - Univesity of Puerto Rico

Life Sciences

Functional Role of UPF2 Phosphorylated Regions in Translation Termination in Yeast

Eukaryotes have evolved a unique mechanism for recognizing premature termination codons (PTC) present on the mRNA. These PTC-containing mRNA’s are recognized and degraded by a mechanism known as nonsense-mediated mRNA decay (NMD), which prevents the formation and accumulation of non-functional or truncated proteins that can be the starting point for several human diseases, such as Cystic Fibrosis and Duchenne Muscular Dystrophy. One of the proteins involved in NMD is the up-frameshift protein 2 (UPF2), which has been shown to be phosphorylated and essential for the accuracy of translation termination. However the functional role of Upf2 phosphorylated residues in the translational termination accuracy is still unknown. To test this we perform several deletions in the UPF2 phosphorylated regions containing phosphorylated residues and measured the growth rate of Saccharomyces cerevisiae strain that harbor the allele can1-100 in the presence of canavanine. Results demonstrated that the deletion of the regions in Upf2 corresponding to amino acids (aa) 50-59 and 421-430, showed less growth due to a higher sensitivity to canavanine caused by a faulty translation termination. This suggests that these regions are crucial in the accuracy of translation termination and provide a foundation for future studies to determine the role of Upf2 phosphorylation in the fidelity of translation termination in eukaryotes.

Hernandez-pena, Arnaldo

Life Sciences

233

Determination of seed viability in Campylocentrum pachirrhizum using histochemical stains.

The ability of reproduction in plants depends in part on the viability of the seeds. A literature search shows that the viability of seeds in plants can vary from 0 to about 100%. The cause of the absence of production in plant embryos are multiple, including for example inbreeding, genetic incompatibility or lack of resources and quality of pollen. In this study we determined the success of embryos in the seeds of the orquid Campylocentrum pachirrhizum. The presence of embryos was determined using histochemical staining. To isolate the seeds we first counted five fruits from five different individuals. In each fruit was evaluated the presence of embryo in a sample of over 100 seeds. It was found that the average of embryo in the seeds of all plants is 95%. We observed that the percentage of embryos in the plant is high.

Holder-Viera, Mileyshmi

Jose Antonio Lasalde-Dominicci - Department of Biology, University of Puerto Rico, San Juan, PR; Carlos Alberto Baez-Pagan - Department of Biology, University of Puerto Rico, San Juan, PR

Life Sciences

Characterization of cancer associated somatic mutations from the Alpha-7 nicotinic acetylcholine receptor

Cancer names a very broad group of diseases, all of which involve unregulated cell growth and proliferation. The American Cancer Society estimates the numbers of new cancer cases and deaths expected in the United States and a total of 1,658,370 new cancer cases and 589,430 cancer deaths are projected for 2015. Smoking is estimated to account for approximately 4-5 million deaths worldwide and approximately 443,000 deaths each year in the United States alone. Cigarette smoking highly correlates to the onset of a variety of human cancers, and continued smoking is known to abrogate the beneficial effects of cancer therapy. The predominant cancer in the developed world is lung cancer and its onset is strongly correlated with smoking habits. Nonetheless, despite the strong linkages between smoking and lung cancer, approximately 30% of smokers with lung cancer continue to smoke following their diagnosis. This study aim to characterize confirmed somatic mutations found in the CHRNA7 gene. Xenopus laevis oocytes expressing

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either wild type or coding somatic mutations of the CHRNA7 gene will be used as our model and electrophysiological characterizations will be performed by means of two-electrode voltage clamp. The characterization of each mutation aims to determine the receptor’s responsiveness to acetylcholine and nicotine; and to test common antagonists to evaluate and compare IC50 values. Results from this study could contribute a pharmacogenomics approach to drug therapeutics regarding tumor growth inhibition and negative side effects prevention based on acquired data that validates receptor/antagonist interactions for each studied CHRNA7 gene somatic mutation.

Jimenez-Ramos, Valeria

Jescelica Ortiz Rivera

Life Sciences

Efectividad de Productos caseros y comerciales para el cuidado de bacterias presentes en el rostro

Nuestra piel consiste de invaginaciones cutaneas tales como glandulas sebaceas y foliculos donde alberga un microbioma unico, algunos causantes de desordenes cutáneos como el acne. Se han establecido un sin número de tratamientos comerciales entre ellos Neutrogena, Clean & Clear y Clearasil, los cuales funcionan como agentes antimicrobianos. Personas que tienen este desorden cutáneo han buscado nuevas alternativas caseras tales como aspirina, limon y Vicks para tratar este tipo de condicion. En esta investigacion establecimos la efectividad de productos caseros y comerciales en el control de bacterias presentes en el rostro de cuatro individuos varones de aproximadamente 20 a 22 años de edad mediante el metodo Kirby-Bauer. Los resultados y analisis estadísticos revelaron que los productos caseros especi?camente aspirina y limon mostraron una mayor inhibicion en la proliferacion de bacterias presentes en el rostro.

Jusino-Cotto, Shirley

Godoy, Lenin - Pharmacology and Toxicology, Ponce Health Sciences University; Albino, Elinette - Pharmacology and Toxicology, Ponce Health Sciences University;

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Ortiz, Carmen - Pharmacology and Toxicology, Ponce Health Sciences University; Hill, Martin D. - Pharmacology and Toxicology, Ponce Health Sciences University

Life Sciences

Drug-associated DNA damage in HIV-1 Patients taking HAART

Despite the reduction in mortality in HIV-1 patients due to the use of highly active antiretroviral therapy “HAART”, adverse effects have been associated to long-term usage. Recently, several studies have demonstrated that HIV-1 patients are under chronic oxidative stress caused by an inflammatory response to the latent infection, or as an adverse effect of the antiretroviral therapy. The aim of this study was to evaluate the DNA damage in peripheral blood mononuclear cells “PBMCs” of HIV-1 patients treated with HAART when compared to healthy donors. Frozen PBMCs obtained from HIV-1 subjects with undetectable viremia and under HAART were used for this study. An aliquot of the thawed cells was used for DNA isolation and the remaining cells were cultured for seven days. Single and double-strand DNA breaks were evaluated using an alkaline gel electrophoresis and the neutral comet assay, respectively. PBMCs from healthy donors were used as negative controls. EMS “ethylmethane sulfonate” was used as a positive control. Interestingly, the alkaline gel revealed higher DNA fragmentation in HIV-1 samples when compared to an HIV-negative control and to the positive control. Additionally, the neutral comet assay showed presence of double-stranded DNA breaks in HIV-1 positive cells when compared to a healthy donor sample. The extent of the single or double-stranded DNA breaks varied among samples depending on type of therapy and the length of time under the therapy. Taken together, our results suggest that HAART may affect the oxidative stress imbalance in HIV-1 patients.

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Justiniano-Sierra, Natalie

Martins, Dr. Antonio Henrique - Biochemistry Department,Central University of the Caribbean

Life Sciences

THE ORGANOPHOSPHATE DFP INDUCES CELL DEATH IN PROGENITOR OF HIPPOCAMPAL RAT

Organophosphates (OPs) represent a human health threat because it damages the developing brain at sub-lethal doses and induce abnormalities in acute exposed adult brains even after treatment with post-exposure medical countermeasures. These compounds can usually be found in pesticides and have even been used as chemical warfare agents. The main effect of OPs is acetylcholinesterase (AChE) inhibition, however evidence have been shown that is not the only one. After acute exposure, if the patient survives with the use of countermeasures, there is a great probability to develop the Gulf War Illness, a syndrome characterized by mood disorders, depression, cognitive deficits, and memory impairment. As neural progenitor cells are related with memory and depression we hypothesized that these cells present in the subgranular layer of hippocampus would be affected by acute organophosphate exposure which can explain some symptoms of Gulf War Illness. In this work, we evaluated whether high concentrations of diisopropylfluorophosphate using a pyridostigmine-ipratropium-diisopropylfluorophosphate (PID) model, simulating an exposure to warfare agent, can alter the NPC viability. Brain tissue from rats treated with saline-saline-water (SSW), pyridostigmine-ipratropium-saline (PIS) and pyridostigmine-ipratropium-diisopropylfluorofosfate (PID). The animals were euthanized after 24 hours, 48 hours and 7 days. Long term inhibition of AChE and ERK phosphorylation were observed 24 hours and 48 hours after intramuscular injection of PID. In addition, a decrease in doblecortin positive cells, which is a marker for NPC and young neurons in the subgranular layer, as well as an increase in number of cell death were observed 7days after the induction of insult. In conclusion, we observed that young neurons/NPC are susceptible to injury triggered by diisopropylfluorophosphate and the inhibition of AChE persists for at least seven days.

Laureano-Figueroa, Stephanie

237

Esteban, Ernesto - Physics, UPRH; Mojica, Noemi - Biologia, UPRH

Life Sciences

A Quantitative Model for Benign Prostatic Hyperlasia (BPH) Dynamics

An enlargement of the prostate called benign prostatic hyperplasia BPH is a common condition in aging men. Epithelial benign prostate cells secrete to the bloodstream a serum prostate-specific antigen PSA. Since 1986 a clinical test to measure PSA levels in blood is used worldwide as a marker for prostatic diseases such as BPH and prostate cancer. In this research we developed a mathematical model to study the relationship among prostate volume PSA and age in Saudi and Japanese patients with and without a histologically proven BPH. We found that the prostate volume increases following a cubic equation on time. Also by fitting our proposed model with clinical data we obtained epithelial benign secretion rate and the parameter related to the PSA metabolized by the blood. We have also obtained a BPH cutoff value that depends of the mans ethnicity. Therefore BPH patients with higher values than the PSA cutoff value are likely to have BPH and prostate cancer.

Lefebre-Rivera, Monica A.

Lefebre Rivera, Monica A. - Department of Natural Sciences and Mathematics, Inter American University of Puerto Rico - Bayamon Campus; Garcia-Arraras, Jose E. - Department of Biology, University of Puerto Rico - Rio Piedras Campus

Life Sciences

Characterization of neuronal and neuroendocrine cells in the luminal epithelium of Holothuria glaberrima

Echinodermata is a phylum of marine animals that lie at the basal branch of the deuterostome evolutionary branch. They have a radial morphology that includes a radial nervous system. Recent work by our laboratory and others have explored the echinoderm nervous components. Here we evidence the neurosecretory component of their digestive system. Immunohistological techniques, were used to identify the neuroendocrine cells of Holothuria glaberrima in 4 digestive tract

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regions: the esophagus, the descending small intestine, ascending small intestine, and the large intestine. In particular, the antibodies RN1, anti-GFS, anti-Calbindin, anti-Galanin, anti-GABA and anti-Nurr1 were used to observe, describe and quantify the neuroendocrine cells. Different morphologies, abundance and locations suggest that these neuroendocrine type cells are two different subpopulations. Labeling with other antibodies is being done to clearly define the complete catalogue of neuroendocrine cells in the digestive system. The results obtained through these studies will provide important information on echinoderm anatomy, nervous system connectivity, and for future studies of cellular differentiation during intestinal regeneration.

Liquet-Gonzalez, Jose

Dumar, Zachary - Khadempour, Lily; Currie, Cameron

Life Sciences

Leaf-cutter Ant, Atta cephalotes, Consumption Behavior of Leaf Discs Infused with Different Antibiotics

The leaf-cutter ant system is a fundamental example of insect-microbe interaction. They cultivate and feed a mutualistic fungus, in this case Leucoagaricus gongylophorus, with plant biomass. The fungus, in exchange, metabolizes the biomass into nutrients suitable for ant consumption. Furthermore, the ant colonies have complex bacterial communities inside their fungus gardens. Although the members have been characterized, their role is still a mystery. It is thought that they help the fungus with the degradation of plant biomass, but there is no certainty. By using a vacuum we infused Quercus velutina leaf discs with different antibiotics, which were used as substrate. We used this substrate to potentially inhibit growth of certain bacterial populations inside the fungus gardens. 18 leaf-cutter ant subcolonies were made; each contained a fungus chamber, refuge dump and food trait. Each subcolony had an specific treatment randomly assigned. We fed them for 21 days and documented daily their leaf consumption. The ants showed a preference for control leaves over antibiotic infused. Their consumption of antibiotic infused leaves compared to the control leaves started to decline by day 2. If bacteria was indeed inhibited, this behavior could suggest possible communication between bacteria-ants or bacteria-fungus-ants regarding the choice of substrate. Furthermore, it could suggest that taking out bacteria from the fungus gardens makes the leaves degradation process slower, thus slowing the consumption of the

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subcolonies. These findings can help in discovering a cellulose degrading microbial community, which is important for bioenergy purposes.

Lopez-Alfonzo, Erika

Roman-Morales, Elddie - Chemistry Department, UPRM; Lopez-Garriga, Juan - Chemistry Department, UPRM

Life Sciences

Sulfmyoglobin Conformational Change: An Angle in the Decrease of Myoglobin Functionality

Hemoglobin (Hb) and myoglobin (Mb) are globular proteins that are in charge of the oxygen (O2) transport in the human body. Studies have demonstrated that when the body is exposed to a high concentration of hydrogen sulfide, a recently identified signaling gas, a type of anemia called sulfhemoglobinemia can be developed. This condition is triggered by the formation of a protein derivate named the sulfheme complex, which reduces the protein’s affinity towards O2 by a ~135 fold in Hb and ~2500 fold in Mb. Previous studies have suggested that this change in affinity may be guided by heme group distortion caused by the addition of the sulfur atom and its electron withdrawing forces, but the overall changes in protein conformation have not been broadly studied. The aim of this study was to evaluate if there is a significant change in protein conformation that may lead to changes in affinity towards O2 and therefore affect the protein’s primary function. Samples of oxyMb and sulfMb, along with the control protein HbI from Lucina pectinata, were prepared and tested using Small Angle X-ray Scattering in the X-9 Beamline of NSLS I at Brookhaven National Laboratory. Results for the Guinier, Kratky, Porod-Debye plots, and P(r) functions for Mb and HbI were evaluated and compared. It was observed that the sulfheme complex formation induced a change in conformation where Mb is found to be less compact, more flexible and disordered. These results suggest that the sulfheme complex affects the conformation of Mb and therefore may have a negative effect in protein function playing a role in the decrease of O2 affinity.

Lopez-Melendez, Gerardo

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Colón-Piñeiro, Zuania - Department of Biology. University of Puerto Rico Rio Piedras Campus; Restrepo, Carla - Department of Biology. University of Puerto Rico Rio Piedras Campus

Life Sciences

Quantifying the ossification of skeletal system during the development of the common coqui (Eleutherodactylus coqui) through image analysis

The skeletal system of vertebrates experiments numerous changes during development, including differentiation, chondrification, ossification, fusion, and growth of the skeletal elements. A growing number of studies show that a variety of genetic and environmental factors are associated with the appearance of skeletal abnormalities in amphibians. Few of these studies, however, have examined the process underlying these changes. The purpose of this work was to develop a protocol to quantify the extent of differentiation between cartilage and bone in Eleutherodactylus coqui. Towards this end we used cleared and double stained embryos to quantify the amount of cartilage and bone observed in embryos. First, we experimented with different ways to collect and pre-process digital images of cleared and stained embryos. Second, we explored the combination of different bands and band ratios to generate indexes that could differentiate between cartilage (stained blue) and bone (stained red). Lastly, we used the number of pixels to quantify the amount of cartilage and bone. Our preliminary results show that a 7:1 (Red:Green) ratio for the red layer and a 7:1+1 (Blue:Red+Green) ratio for the blue layer can differentiate between these two tissues, as long as the staining and images are of good quality. This protocol can be used with any vertebrate that has been cleared and double-stained.

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Lopez-Torres, Abdon

Caroline B. Appleyard - Department of Physiology & Pharmacology, Ponce Health Sciences University; Myrella L. Cruz - Department of Physiology & Pharmacology, Ponce Health Sciences University; Héctor M. Colón Perez - Department of Medicine, San Juan Bautista School of Medicine; Siomara Hernandez - Department of Physiology & Pharmacology, Ponce Health Sciences University; Raymond A. Isidro - Department of Physiology & Pharmacology, Ponce Health Sciences University; Angel A. Isidro - Department of Physiology & Pharmacology, Ponce Health Sciences University

Life Sciences

Exposure to Stress Increases Vitamin D Receptor Expression and Macrophage Infiltration in an Animal Model of Endometriosis

Endometriosis is a gynecological disorder defined as the growth of endometriotic tissue in the form of cysts outside of the endometrial cavity. This chronic condition is characterized by inflammation, fibrosis, adhesions and chronic pelvic pain. The vitamin D receptor VDR, which is expressed in the cycling endometrium, is associated with anti-proliferative and anti-inflammatory properties; however, its role in endometriosis is still unclear. Stress can affect the immune system and disrupt VDR, and therefore may contribute to the development and progression of endometriosis. AIM: To investigate the impact of stress on VDR expression and macrophage infiltration in cysts from an animal model of endometriosis. METHODS: Endometriosis was surgically induced in female Sprague-Dawley rats by suturing uterine horn tissue next to the intestinal mesentery. Some rats were exposed to a swim stress protocol for 10 days. At sacrifice all rats were examined for development of cysts. Colon and uterine tissue were analyzed for damage and myeloperoxidase levels. Macrophage infiltration and VDR expression in the cysts were measured by immunofluorescence and immunohistochemistry respectively. RESULTS: Cysts were larger and more frequent in endo-stress rats compared to endo-no stress rats. The endo-stress animals also had more colonic damage and inflammation. Exposure of the animals to stress increased macrophage infiltration p<0.05 and VDR expression in both the glands and stroma of cysts p<0.05. CONCLUSION: Stress enhances development of cysts in an animal model of endometriosis through mechanisms involving macrophage recruitment and VDR regulation. These results may point towards future therapeutic targets. Supported by R15AT006373

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Luna-Serrano, Rochely

Shen, Anna Lee - Oncology, Madison Wisconsin at UW- Madison, Madison, WI2; Bradfield, Christopher A. - Oncology, Madison Wisconsin at UW- Madison, Madison, WI2

Life Sciences

The PPCD1 Mouse: Genetic Basis and Phenotypic Characterization

Posterior Polymorphous Corneal Dystrophy (PPCD) is an autosomal dominant disorder that causes epithelialization of the corneal endothelium. In some cases, this disorder leads to visually significant corneal edema and glaucoma. A previous study has identified a hemizygous 3.8 Mbp chromosomal inversion coupled with an 87,000 bp deletion in the mouse PPCD1 locus. The two disrupted genes are Csrp2bp and DZank1. The overall goal of this study was to identify the progression by which the chromosomal rearrangement leads to the observed phenotype in mice with different genetic background; DBA/2J (DBA) and C57BL/6J (B6). PCR genotyping was performed to distinguish mutant and wild- type animals. Immunohistochemistry (IHC) in eye sections allowed observation of developmental progression. Briefly, sections were incubated overnight of E-cadherin to observe mesenchymal to epithelial transition in mutant eyes. Other sections were incubated with anti- cytokeratin (Clones AE1/AE3. PCR genotyping showed that both DBA and B6 mice expressed wild type and mutant bands and identified PPCD1 animals. Phenotypically, PPCD1 mice on the DBA background displayed very enlarged eyes by eight days after birth, and strong E- cadherin and pan- cytokeratin immunoreactivity by three weeks of age. While the appearance of these phenotypes is slower and different in PPCD1 mice on the B6 background. E-cadherin expression in epithelialized endothelial cells confirms the hypothesis that these abnormal corneal endothelial cells have undergone mesenchymal to epithelial transition. Slower progression on the B6 background suggests the presence of genetic modifiers that influence development/progression of the PPCD1 phenotype.

Luna-Torres, Julie

244

Chen, Shuibing - Surgery Department, Weill Cornell Medical College; Mukarjee, Suranjit - Surgery Department, Weill Cornell Medical College

Life Sciences

Use of CRISPR-Cas 9 to Develop a Human Embryonic Stem Cell Line Carrying the Trp64Arg Mutation of the Beta-3 Adrenergic Receptor

Obesity is a leading public health problem in the United States. Current strategies to prevent obesity have been unsuccessful which is why new approaches to understand energy expenditure and fat storage in humans are necessary. Brown adipose tissue (BAT), has the ability to dissipate energy by producing heat, rather than storing energy as fat as seen in white adipose tissue (WAT). The presence of BAT is inversely correlated with BMI and understanding how defective human brown fat cells relate to obesity is a critical step in elucidating new therapeutic strategies. In human WAT cells, the Trp64Arg mutation in the Beta-3 adrenergic receptor gene (ADR?3) has been associated with diabetes mellitus type 2, fat accumulation, insulin resistance, and defective lipolysis (Umekawa, 1999). We aim to understand the effect of this mutation in human BAT. To do so, the genome editing system clustered regularly interspaced short palindromic repeats (CRISPR)-Cas9 will be utilized to design a mutant human embryonic stem cell line. Several guide RNA (gRNA) sequences will be analyzed to assess which CRISPR construct functions most efficiently. Subsequently, the construct will be introduced into the human embryonic stem cells along with a donor homology template to introduce the mutation. The stem cells will be further differentiated into human BAT where the mutation can be further studied. We expect to find a gRNA sequence that can: 1) successfully integrate into the CRISPR plasmid, 2) target the desired site in the genome and 3) efficiently cleave and create a double strand break in the DNA. By generating a functional Trp64Arg CRISPR construct and competent mutant and wild type BAT, future studies on the role of BAT cells in obesity and its related secondary complications will be facilitated.

Maldonado-de jesus, Jorge

Yamamura, Y - AIDS Research Program Immunology Reference Laboratory at Ponce School of Medicine; López, P - AIDS Research Program Immunology Reference Laboratory at Ponce School of Medicine; Rivera-Serrano, A - Universidad Del Este, Carolina; Álvarez, D - Universidad Del Este, Carolina; Roig-López, J - Universidad Del Este, Carolina

245

Life Sciences

In Vitro Characterization Of Cell Population Derived From Neural Stem Cells (NSC) Using Flow Cytometer In Cellular Hypo-Methylated Environment.

There are different mechanisms for the regulation of gene and protein expression, such as genomic DNA methylation of cytosine. Studies have demonstrated that the presence of 5-methylcytosines plays an important role in regulating the gene and protein expression of neural and glial genes. Earlier experiments show not significant change in the percentage of glia and neural markers under the hypo-methylated agent 5- Aza-2-deoxycytidine using immunofluorescence microscopy and Image J Analysis software. In these preliminary experiments quantification of the Glial markers was difficult due to cellular aggregation. In order to avoid misrepresentation of one of the markers want to use Flow Cytometry to obtain reliable quantification of all the cell lineage markers. The differentiation of NCS was done for twelve days in a six well plate with a cell planting density of 4.0-8.0 x104/cm² in a mix of neurotrophic factors, B27 and N2 supplements without growth factors. Primary antibodies; beta-tubulin 1/500 and GFAP 1/1000 were used for lineage commitment and characterization with corresponding secondary antibodies. Cells were lifted with Accutase enzyme following product information. BD FACSAria was used for the characterization of the cell population. Proper characterization by the side scattered and forward scattered shows typical population of homogenous phenotype non – staining control. This non-staining control is essential for setting the initial parameters for cell population analysis. Results from these experiments will help predict changes in the commitment and differentiation of human neural precursor cells and could be applied to the development of cell replacement therapies.

Maldonado-Vazquez, Natalia

Dra. Angelica Barrero-Tobón - Microbiology and Immunology department, University of north Carolina-Chapel Hill; Dr. Peggy Cotter - Microbiology and Immunology department, University of north Carolina-Chapel Hill

Life Sciences

246

Interaction between BcpA-CT toxin with B. thailandensis susceptible mutants

Contact dependent growth inhibition (CDI) is a phenomenon observed amongst Gram-negative bacteria. CDI, is mediated by the Toxic C-terminus (CT) of a large surface exoprotein, to inhibit the growth of neighboring susceptible bacteria upon cell-to-cell contact. We are studying CDI in members from the genus Burkholderia. Some members of this genus are pathogenic and considered potential bioweapons, like B. pseudomallei. The work presented here was performed using a closely related organism, B. thailandensis, which is not a pathogen and it is safe for laboratory environments. In Burkholderia, the CDI encoding locus is bcpAIOB. Our research focuses on understanding the most relevant interactions between BcpA and target bacterial cells. To study BcpA we generated constructs for protein expression containing a catalytically inactive form of B. thailandensis bcpA in the absence of bcpI. The resulting proteins were purified and used to perform immunoassays and cell killing assays using the susceptible B. thailandensis ?bcpAIOB cells. Results from dot-blot analyses suggest that there is no significant binding between these protein fragments and susceptible cells (?bcpAIOB). Killing assays with ?bcpAIOB cells and proteins incubated with catalytically inactive fragments of BcpA-CT bound to BcpI, showed that these fragments are presenting some cell killing. Further experiments will be performed to analyze the interaction between isolated BcpI and susceptible cells. All together, understanding CDI will help understand more about the role of this natural bio-control mechanism.

247

Manoharan-Valerio, Michael

Noel, Richard - Biochemistry, Ponce Health Sciences University

Life Sciences

2D Gel: A proteomic analysis

2D Gel proteomic analysis.

Marrero-Ramos, Luis

Luis O. Marrero-Ramos - Dept. Natural Science, Universidad Interamericana de Puerto Rico, Bayamon; Dr. Rafael R. Canales-Pastrana - Dept. Natural Science, Universidad Interamericana de Puerto Rico, Bayamon; Dr. Bert Rivera-Marchand - Dept. Natural Science, Universidad Interamericana de Puerto Rico, Bayamon; Dr. Steven Lapointe - USDA ARS Horticultural Research Laboratory, Fort Pierce, Florida

Life Sciences

Bio-geographical distribution of the color variations in the sugar cane root weevil Diaprepes abbreviatus in Puerto Rico

The neotropical root weevil Diaprepes abbreviatus is a recognized agricultural pest. Its larvae and adults are known to feed on >300 different plant species and have caused extensive damage to citrus through root feeding and by facilitating infection by soil-borne pathogens. In order to manage this weevil it is important to examine it in its native environment. Based on color variation it has been hypothesized that D. abbreviatus originated in the Caribbean, specifically on the island of Puerto Rico. The colors include red, orange, yellow, white, grey and brown. The color variation may be due to bio-geographical factors, host plant interactions, or they may be associated with discrete populations. Using GIS technology we examined the distribution of color morphs based on museum specimens collected by municipality between 1948 and 2014. We did not find a correlation between bio-geographical

248

distribution and color. This may be due to an absence of a distributional pattern based on color or a small sample size. For future studies exact coordinates of collections will provide more precise mapping data. The results of this analysis will contribute to understanding the phenotypic variability, distribution and recent movement of D. abbreviatus and contribute to its management.

249

Marrero-Santiago, Wilmarie

Acosta-Colon, Angel - Physics and Chemistry Department, University of Puerto Rico at Arecibo

Life Sciences

Mesofauna Biodiversity of Matos Cave at Arecibo, P.R.

The Matos Cave STEM project was created to develop future scientist in the area of applied geosciences and speleology. The students of the project apply their field of study (i.e. chemistry, biology, computer science, etc.) into a research project in Matos Cave. The main goal of the project is to understand the properties of the cave. Matos Cave is located in the north coast karst belt region of Puerto Rico, specifically in the municipality of Arecibo. The main purpose of this study is to characterize the geobiological properties of the cave, more specifically the soil mesofauna (arthropods from 0.1 ~ 2 mm in size) in the cave ecosystem. The soil mesofauna was characterized using tow different types of traps as a function of the cave depth and we collected around 5,000 specimens. These specimens were classified by a biological order or class. Aditionally, the bats of the cave were characterized to study the relationship between guano per bat species and mesofauna species collected. After the characterization, a statistical analysis was performed to obtain species diversity (Shannon Method) and relative abundant as a function of the cave depth. The results showed that we found 14 biological order or class and the cave and variability depending the geochemical parameters of the cave and bat colonies that feed the ecosystem.

Martinez-Montes, Eduardo

Martinez, Marina - Dept. of Biochemistry UPR-MSC; Gonzalez, Jose A. - Dept. of Biology, UPR-RP; Gonzalez, Carlos I. - Dept. of Biology, UPR-RP

Life Sciences

250

Identification of HuR interacting proteins during T cell activation in Jurkat T cells

HuR (Hu antigen R) is a protein member of Hu family that is involved in numerous biological process. It is has been extensively studied in inflammation and cancer research. Moreover, this protein affect the regulation of mRNA stability and translation in cancer cells. Several HuR mRNA targets are p53, TNF?, Fos, murine IL-3 and Bcl-2. We hypothesize that remodeling of protein partners during T cell activation is a pivotal event in the inflammatory response, thus alterations in HuR associated proteins are expected. Our goal is to identify HuR interacting proteins in Jurkat T cells during resting state and T cell activation at 6 hours. In order to achieve to estimate the associated proteins of HuR we used two bioinformatics analysis. In addition, immunoprecipitation (IP) using an antibody against of HuR coupled to a silver staining and western blot approaches. HuR interacts with specific proteins between 25-250 kDa at resting and activated state compared with the absent of HuR. In conclusion, a protein partner of HuR are remodeling during T cell activation. Bioinformatics analysis found predicted interacting proteins such as AGO2, HNRNPK, XPO1, PTBP1 and PTBP2. A future direction of this project is to determine the specific proteins partners of HuR at different time point of activation using Mass Spectrometry analysis. Eventually, the identification of these HuR interacting proteins can provide new insights about the mechanism of HuR in several cancers, inflammatory response and neurological diseases.

Mendez-Vargas, Melanie

Ramos, Diadette - Natural Sciences; Medina, Glenys Y. - Natural Sciences; Vélez, Marian - Natural Sciences

Life Sciences

Does captivity affect protein profile in males Anolis pulchellus?

Humans are constantly exposed to several substances that affect normal processes of our body. Some of these toxic compounds interfere with the natural functions of hormones; called endocrine disrupting chemicals (EDCs). This action cause detrimental effects in many organisms health. For this reason it’s necessary to find ways to detect these substances before they can cause more danger. The Anolis pulchellus lizard has been shown to have the potential to work as a sentinel organism. It had being used to detect and evaluate xestrogens. To do these investigations, because we don’t have the resource to collect samples near us, it’s

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necessary to capture them one or more days before they are going to be used and keep them in captivity. The objective of our research was to determine if short time captivity affected the presence of the proteins in the protein profile of the lizard. We collect our samples, observed them during, and analyze them after 4, 10 and 20 days of captivity. We sacrifice the animal, collected the blood and analyze it using SDS-PAGE to see if after the captivity, the protein profile changed, compared with a control. Although there was a change in the weight of the lizards, the results from the SDS-PAGE showed that the lizard’s protein profile, as comassie blue staining let us to appreciate, was not affected by the captivity. These results suggest that the captivity period studied in the lizards may not have effects on the results of future experiments made with these organisms.

Mendez-Vazquez, Erika

Mateo Mayol, Zaira Ph.D - Pontificia Universitad Catolica de Puerto Rico

Life Sciences

N-Acetyl-Aspartyl-Glutamate Quantification Using HPLC Method in Adult Zebrafish Brain

N-Acetyl-Aspartyl-Glutamate (NAAG) is one of the most abundant neuropeptide in the central nervous system of mammals. It is synthetized by neurons from glutamate and N-acetylaspartate (NAA). In mammals like rabbit, bovine, horse, including humans have been found measurable amounts of this neuropeptide. NAAG have been shown to affect long term potentiation and depression in structures like the hippocampus. Certain neurological disorders have involved dysfunction of glutamate neurotransmission. In addition, recent evidence suggest that the imbalance between NAA and NAAG in hippocampal structure are important in neuropsychiatric disorders like schizophrenia. Therefore, understanding the role NAA and NAAG participation in the glutamatergic neurotransmission may open new avenues to the treatment of certain neurological disorders. Zebrafish (Danio rerio) is an important model in neurological research due to its high physiological and genetic homology to humans, ease genetic manipulation and similar central nervous system morphology. Recent studies using HPLC analysis demonstrate that zebrafish possess neurotransmitters like dopamine, serotonin and glutamate. This findings suggest that zebrafish contains glutamatergic synapses as well other kind of synapses similar to humans. Glutamatergic neurotransmission have been shown to be modulated by metabotropic glutamate receptors (mGluR). The mGluR family is divided in three groups based on its sequence homology and physiological

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activity. This family of receptors have been implicated in a wide variety of modulatory synaptic mechanisms. Recently, a novel clinical research approach involves the study (mGluR) as an alternative treatment in neurological disorders. Previous studies, indicate that NAAG is a selective agonist type 3 mGluR a member of the group II family. In our lab, we are interested to determine if zebrafish is a possible biological model to study type 3 mGluR through NAA and NAAG. First, we are interested determine the presence of NAAG and/or NAA. To approach this objective, we will measure NAA and NAAG with and without the exposure to carboxypeptidase II inhibitor in zebrafish. By using HPLC method we would like to quantify the concentration of these two neuropeptides.

Menendez-Santos, Manuel

Angel G. Rivera-Colón - Universidad de Puerto Rico, Rio Piedras; Mathieu Joron - Muséum National d'Histoire Naturelle, Paris; Antónia Monteiro - National University of Singapore; Riccardo Papa - University of Puerto Rico, Rio Piedras

Life Sciences

Wing morphometrics for the analysis of dorsal hindwing eyespot number variation in the butterfly Bicyclus anynana

Butterfly wings are complex systems of study, as they present integration of genetics, development and environment for the production of diverse phenotypes, including wing pigmentation patterns and morphological variation. Butterfly wing morphology, particularly wing shape, is especially complex because of its multidimensional properties. In the butterfly Bicyclus anynana, variation in both wing morphology and in dorsal eyespot number is observed. In our study, we performed morphometric analysis of B. anynana wings to determine how variation in wing morphology relates to dorsal hindwing eyespot number. Using landmark morphometrics approach of homologous structures in the wing, we assess wing shape variation with vectorial measurements of both magnitude and direction of variation utilizing geometric morphometrics analysis software. Hindwing eyespot number appears not to be correlated to wing morphology, as sex appears to be the trait most highly correlated with wing shape variation. This suggests that another component, possibly genetic, is responsible for eyespot number variation in B. anynana. Once completed, our study will allows us to better understand butterfly wing variation, especially how the interaction of different environmental, genetic and morphological components give origin to these complex traits, as in butterfly wing patterning.

253

Mercado-Torres, Andrea M.

Hendricks Timothy - Natural Science and Mathematics; Torres Victor - Natural Science and Mathematics

Life Sciences

Functional evaluation of human Wt1 in spinal cord development

We hypothesize that the human WT1 gene will have a similar function to the murine WT1 gene in the development of dI6 interneurons. This is due to the fact that the WT1 gene is highly conserved among chordates. Thus WT1 gene mutations in humans have similar phenotypic outcomes in comparison with murine WT1 knockouts WT1--. More specifically mutations in WT1 cause heart abnormalities and renal and gonadal agenesis in both organisms. Thus the ectopic expression of human WT1 gene in primary neuronal cultures should have a similar effect as their counterpart murine WT1 gene. The human sequence for Wilms tumor 1 Wt1 will be cloned into an expression vector pReceiver for use in cultured primary neurons derived from the developing mouse spinal cord. The expression of the human Wt1 protein will be verified by the use of a myc tag in the pReceiver construct that will be assayed by fluorescence immunohistochemistry. This study will test the hypothesis that human Wt1 is functionally equivalent to the mouse gene in the developing spinal cord.

Monroig-Bosque, Maria del Mar

Rivera, Ivonne - Biology, University of Puerto Rico-Mayaguez; Cafaro, Matias - Biology, University of Puerto Rico-Mayaguez

Life Sciences

Asellaria jatibonicua in the terrestrial isopod Litthorophiloscia culebrae

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The trichomycetes are microorganisms associated with the gut of arthropods. They are an ecological group composed of protists (Ichthyosporea) and fungi (Kickxellomycotina) that converged in a similar life style evolutionary solution with key adaptations to their gut environment. Isopods in particular harbor fungal members belonging to the Asellariales. One essential aspect of the ecology of the Asellariales is to understand the environmental conditions associated to the isopods. For instance, the different environmental fluctuations of temperature, water precipitation and humidity affect the isopods lifestyle and thus, the life cycle of these fungi. In this study we observed seasonality of Asellariales associated to the terrestrial isopod Litthorophiloscia culebrae (Moore 1901) with a low prevalence in the dry seasons and a higher one in the wet seasons. We have found L. culebrae in different forests of Puerto Rico, including Río Abajo, Guajataca and Toro Negro and in different urban localities in Mayaguez. For this reason, we intend to compare the behavior of these organisms and the prevalence of its fungal symbionts in these different localities. Isopods were collected in the University of Puerto Rico, Mayagüez campus and dissected in the laboratory the same day. Slides were made in ddH2O and then fixed with 0.05% lactophenol-cotton blue. In addition, during this study period we found another trichomycete in the same host, Parataeniella sp. (Ichthyosporea: Eccrinales), which represents a first record for Puerto Rico.

Morales-Silva, Roberto

Morales Silva, Roberto - Biology Department,University of Puerto Rico at Ponce; Alvarado-Torres,John - Dominick P. Purpura Department of Neuroscience,Albert Einstein College of Medicine; Boudewyn,Lauren C. - Dominick P. Purpura Department of Neuroscience,Albert Einstein College of Medicine; Walkley,Steven U. - Dominick P. Purpura Department of Neuroscience,Albert Einstein College of Medicine

Life Sciences

Characterization of Dendritogenesis in Cortical Pyramidal Layer V Neurons in Niemann-Pick Type C Disease Using Yellow Fluorescent Protein

Niemann-Pick type C (NPC) disease is an autosomal recessive lysosomal storage disorder affecting mostly children, causing progressive neurological deterioration and death. NPC disease is caused by a mutation in either the NPC1 or NPC2 gene, leading to a loss of functional NPC1 or NPC2 protein. These proteins play a role in lipid egress from late endosomes and lysosomes, a deficiency in either results in

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intracellular accumulation of unesterified cholesterol and gangliosides. Storage is prominent in neurons, influencing cellular pathology, such as growth of ectopic dendrites on pyramidal neurons. This aberrant growth of dendrites following normal dendritogenesis has been documented in several lysosomal diseases characterized by ganglioside storage. Until recently, the visualization of this process depended on the Golgi method. New techniques, such as endogenous expression of fluorescent proteins, provide an in-depth analysis of neuronal structure. We hypothesized that the accumulation of gangliosides in NPC disease will cause an initial enhancement of dendritogenesis along with ectopic dendrite growth followed by a subsequent degeneration of dendritic trees later in disease. Subsequently, we generated a transgenic Npc1 murine mouse model whose layer V cortical pyramidal neurons express yellow fluorescent protein (YFP) to investigate the dendritic abnormalities of NPC disease relative to lysosomal storage. Confocal imaging and Neurolucida Software are being used to image YFP+ pyramidal neurons, which will be analyzed for changes in dendritic size, complexity and pathological state.

Moya-Rodriguez, Lorein

Cardona-Corredo, Albin - Biology Department, UPR-Mayaguez; RIos-Velazquez, Carlos Ph.D - Biology Department, UPR-Mayaguez

Life Sciences

Isolation of toxin component interacting partners using T7 Phage Display from human cDNA libraries

Biological warfare has been the cause of thousands of deaths worldwide proving its efficiency by causing terror. Since the use of Bacillus anthracis spores on 9/18, as a biological agent, research trying to understand the biological mechanism of this bacterium Lethal factor (LF) toxin component has increased. The cleavage performed by LF to the mitogen activated protein kinase results in a cascade of reactions ending in cell apoptosis. Moreover, the damage caused by LF suggests novel interactions with other unknown proteins. The T7 Phage Display (PD) is a technique that allows the identification of protein-protein interactions. This research focuses on the isolation of novel LF interaction partners by PD. Using LF as target, rounds of biopannings were performed with human premade cDNA libraries from stomach expressed on the surface of a bacteriophage (T7). The cDNA present in the LF interacting partners isolated was amplified, sequenced and analyzed in silico. A total of 8 putative LF interaction partners were isolated. In silico data of some of the candidates suggest interactions with proteins with affinity to nucleic

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acids like zinc finger proteins, and transcriptions factors. While new interaction partners is been analyzed, this results will increase the understanding of the functions of proteins with LF for the development of therapeutics in biomedical research.

Negron-Negron, Nilza

Lizette Santos-Santori - Chemistry, Pontifical Catholic University

Life Sciences

Effect of the extract of leaves and stems of Azadirachta indica tree in the CYP450 of Chinese hamster ovarian cells.

The Azadirachta indica tree or better known as Neem has been used since ancient times as a medicinal plant. It’s originally from India, besides being known for its medicinal properties is used in agriculture as fertilizer and insect repellent. It is said to help prevent various diseases including diabetes, cancer, Alzheimer, psoriasis, AIDS, dental disorders, allergies, ulcers, dermatology, herpes, and other conditions. Efficiency of extracts of Neem leaf dried and not dried, the dried stem and not drying are being tested. Chinese hamster ovarian cells were cultivated to study the effect of the extracts in different concentrations on CYP450 in such cells. Then cell microsomes were held to make biochemical tests. The following assays will be performed: Bradford, hydroxylation of p-nitrophenol, activity of 7-ethoxyresorufin (EROD), erythromycin N-demethylase-(ERND) and cytochrome P450 assay. Toxicological tests were carried out using brine shrimp. The procedure was repeated three times and then averaged to obtain the results. Later Chinese hamster ovarian cells were cultivated to induce cancer, and then be treated with the extracts of Neem. With this, we will analyze if the cancer proliferates or inhibited. The assays described above would be replicated to see if the CYP450 system is affected.

Noble-Cruz, Gabriel

Hernández, Marimar - Department of Biochemistry,University of Puerto Rico- School of Medicine; Duque, Maria F. - Department of Biology, University of Puerto

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Rico- Río Piedras Campus; Rivera, Stephanie - Department of Biology, University of Puerto Rico- Río Piedras Campus; Raimundi, Antonio - Department of Biology, University of Puerto Rico- Río Piedras Campus; González, Carlos I. - Department of Biology, University of Puerto Rico-Río Piedras Campus, Department of Biochemistry, University of Puerto Rico- Sch

Life Sciences

Effect of p38 on IL-3 mRNA translation on activated T-cells

Interleukin-3 (IL-3) is a pro-inflammatory cytokine released by activated T-cells that supports proliferation and differentiation of myeloid cells. IL-3 is present in the process of angiogenesis and its deregulation of IL-3 has been associated with several diseases such as multiple myeloma and leukemia. IL-3 mRNA contains Adenine/Uridine-rich elements (AREs), which are sequences that affect the post-transcriptional regulation, within its 3’-UTR. The trans-acting factors known as ARE-Binding Proteins (ARE-BPs) are involved in the stabilization of mRNAs harboring these regulatory elements. The ARE-mediated post-transcriptional regulation is regulated by the p38-MAPK signaling pathway. p38 is highly relevant during translation of mRNA that are expressed upon T-cell activation. To evaluate the possible role of p38 in the IL-3 mRNA translation, Jurkat cells were incubated in the presence of the p38 inhibitor and activated with phorbol-12-myristate-13-acetate (PMA), Ionomycin (IO), PMA/IO and the vehicle (DMSO) for 0, 6, and 12 hours. Then, the IL-3 mRNA polysomal distribution was determined. Cytoplasmic extracts were centrifuged in a continuous sucrose gradient (7-47%) and the RNA was isolated from different fractions. RT-PCR was conducted to measure IL-3 mRNA levels in the fractions. Results demonstrated that both, PMA and IO have to be present in order to promote IL-3 expression with an increase at 6 hours after activation. Furthermore, a change was observed in fractions absorbance after p38 inhibition. Altogether, these results suggest that global translation on activated T-cells is affected by the p38 MAPK signaling pathway.

258

Ortiz-Rivera, Jescelica

Ortiz, Jescelica - Ciencias Naturales, UPR-Bayamon; Jimenez, Valeria - Ciencias Naturales, UPR-Bayamon

Life Sciences

Efectividad de Productos Caseros y Comerciales para el cuidado del Acné en el Control de Bacterias Presentes en el Rostro

Nuestra piel consiste de invaginaciones cutaneas tales como glandulas sebaceas y foliculos donde alberga un microbioma unico, algunos causantes de desordenes cutáneos como el acne. Se han establecido un sin número de tratamientos comerciales entre ellos Neutrogena, Clean & Clear y Clearasil, los cuales funcionan como agentes antimicrobianos. Personas que tienen este desorden cutáneo han buscado nuevas alternativas caseras tales como aspirina, limon y Vicks para tratar este tipo de condicion. En esta investigacion establecimos la efectividad de productos caseros y comerciales en el control de bacterias presentes en el rostro de cuatro individuos varones de aproximadamente 20 a 22 años de edad mediante el metodo Kirby-Bauer. Los resultados y analisis estadísticos revelaron que los productos caseros especi?camente aspirina y limon mostraron una mayor inhibicion en la proliferacion de bacterias presentes en el rostro.

Ortiz-Rodriguez, Keyshla

Timothy Hendricks, PhD. - Department of Natural Sciences and Mathematics, Interamerican University of Puerto Rico

Life Sciences

Chronic Activation of Notch1 Signaling In Vitro

The Notch1 gene encodes a transmembrane receptor for membrane-anchored ligands. The downstream signal from the Notch1 receptor plays multiple roles during development. Notch1 is activated upon binding to ligands from the

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Delta/Serrate/Lag2 (DSL) family. We propose to express a constitutively active form of the Notch1 gene in cultured neural precursor cells in order to examine its role in the differentiation of dI6 interneurons. This study will test the hypothesis that the Notch1 type signaling is required for the expression of Wt1 in dI6 interneurons. A fragment of the murine Notch1 gene sequence will be cloned into an expression vector (pReceiver) to express the intra-cellular domain (ICD). Since the ICD is cleaved following activation of the Notch1 receptor this is predicted to constitutively activate the Notch1 signaling pathway in cells expressing the modified recombinant protein. Expression of the recombinant protein will be verified by detection of a myc tag by fluorescence immunohistochemistry.

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Pagan-Marchese, Kimberly

Mari Acevedo

Life Sciences

Comparison of Lactase enzimatic activity in various commercial products for the treatment of hypolactasia

According to the National Digestive Diseases Clearinghouse at the National Institute of Health, 75% of adults in the United States experience reduced activity in lactase enzyme produced by the small intestine epithelium; a condition that leads to intolerance to the disaccharide lactose. This condition is easy to control by incorporating changes in the diet or supplementing the diet with exogenous Lactase enzyme. Various sources of exogenous commercial Lactase enzyme are available in the market presented in diverse formats and price ranges. There are incidental cases of people reporting different reactions and effectiveness to these products. In this study, we characterized and compared the enzymatic activity of various commercially available Lactase products. Enzyme preparations were compared using solubility and protein concentration assays as well as direct visualization of total protein by SDS-PAGE and functionally by analyzing lactose hydrolysis using cow milk as a source of lactose. We found differences in the solubility of the Lactase products as well as differences in the total protein content. We also found notable differences in enzyme identity based on size differences and number of bands observed by SDS-PAGE. However, all enzymes showed increased enzymatic activity in timecourse experiments and this activity is irreversibly lost by heat denaturation and alkaline pH. Studies are underway to determine possible differences in dissociation constants for each commercial products as well as possible differential effects of stomach contents on the activity of the enzymes.

Pagan-Rolon, Karelis

Rodríguez, Adbiel - Biology, UPR Cayey; Acevedo, Noelia - Biology, UPR Cayey; Chiesa, Ricardo - Biology, UPR Cayey

Life Sciences

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Ethanol Induced Effects of Alkaloid Abstracts in Locomotion in Drosophila Melanogaster

There is a lower incidence and prevalence of anxiety and other behavioral disorders in countries where algae is consumed regularly. We have selected Drosophila Melanogaster as a model to study the effects of organic extracts of brown algae of Puerto Rican coasts in anxiety related behaviors. This model offers several advantages for behavioral and pharmacological studies, because of its similarities in cellular and neurobiological processes with vertebrate organisms. In order to study drug-induced anxiety related behavior in flies, we administered ethanol, which increases locomotion in Drosophila Melanogaster. This behavior serves as a paradigm to measure the anxiolytic effects of the brown algae extract used in this project. After administering ethanol to observe the flies behavior, we can conclude we have validated our paradigm of anxiety-related behavior induced with ethanol. To study the possible anxiolytic effects in flies exposed to ethanol, Drosophila Melanogaster was exposed to a whole organic extract of Sargassum platycarpum over a two week period. After two weeks of exposure of Drosophila Melanogaster to food containing the organic extract of Sargassum Platycarpum, the effects of its behavior in locomotion was evaluated by video recordings and quantitative analysis. Preliminary data shows a decrease in locomotion in Drosophila Melanogaster that was given the extract before ethanol exposure. Further analysis is required to validate this effect on behavior. If anxiolytic effects are found in the brown algae extract, this project opens possibilities to create a new pharmacological treatment for anxiety-related behavior.

Pardo-Garcia, Thibaut

Yusif, Nadira - Psychology, UPR-Rio Piedras

Life Sciences

Dual blockade of FAAH/TRPV1 and indirect activation of CB1 receptors in the Nucleus Accumbens shell

To our knowledge, the functional role of the co-localization of the endocannabinoid CB1 receptor and the TRPV1 receptor within the mesolimbic system has not been studied. Previous studies showed that activation of CB1 receptors within the Nucleus Accumbens shell (NAcshell) have several behavioral effects such as reinforcement and reward. In contrast, TRPV1 receptor actions within the NAcShell

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remain unknown. In the present study, we investigated if the co-localization of CB1 and TRPV1 receptors within the NAc shell plays a key role in the emotional responses mediated by the endocanabinoid system, such as anxiety. In the present experiment, male Sprague Dawley rats were implanted with bilateral brain cannulae aimed at the NAcShell. Following recovery form surgery, animals received pre-treatment of microinfusions (0, 0.25nmol/ 0.4µl) of N-arachidonoyl-serotonin (AA-5-HT), a dual blocker of the endocanabinoid-inactivating enzyme, fatty acid amide hydrolase (FAAH) and a TRPV1 antagonist, within the NacShell. Following treatment, animals were tested in an elevated plus maze paradigm for a period of 10 minutes. Behavioral parameters measured were: Rearing, Flatback approach, Grooming and Head-dip). At the completion of the experiment, animals were sacrificed and their brain collected for histological analysis. Results showed that pretreatment of AA-5-HT within the NacShell significantly increased open arm entries of animals when compared to controls. In addition, stereotyped behavior revealed an anxiolytic response. The present findings suggest that co-localization of CB1 and TRPV1 receptors within the NacShell may be involved in mediating emotional responses. Future studies with more doses are needed to further characterize these pharmacological effects.

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Pedraza-Baez, Valeria

Martínez,Zulmari - Life Sciences, UPR Cayey; Vicente,Jesica - Biology,UPR Cayey; Rivas,Angeliz - Life Sciences,UPR Cayey; Mejias,Keysh - Biology,UPR Cayey; Ramos,Jeslie - Life Sciences,UPR Cayey; Robles,Grisel - Life Sciences,UPR Cayey

Life Sciences

Anxiolytic-Like Effects of an Organic Extract from the Seaweed Sargassum platycarpum in Anxiety-Related Behavior in Drosophila melanogaster

Algae are aquatic organisms that present a great potential for the study of bioactive compounds. Several bioactive compounds with diverse effects have been found in species of algae from the three main groups (classes Phaeophyta Rhodophyta Chlorophyta). We hypothesize that whole organic extracts obtained from brown algae might possess compounds with the potential to decrease anxious behavior. An organic extraction was made using the seaweed Sargassum platycarpum collected from a beach in the south shore of Puerto Rico. The anxiolytic-like effects of the whole extract was tested using Drosophila Melanogaster as the anxiogenic model. Anxiety-like behavioral traits in Drosophila were achieved using the Open Field Arena (OFA) paradigm (phobic behavior) and by the development of insomnia by food deprivation. Before exposure to the algal extracts both anxiety-like behaviors were validated to make certain that the flies presented the expected behavioral characteristics. The whole organic extract from Sargassum platycarpum was dissolved in 23 % Dimethyl Sulfoxide (DMSO) and toxicity tests both for DMSO and the whole organic extract were performed before the behavioral tests. For the behavioral tests 1 ml of whole extract was added to 5 ml of food and adult flies exposed to food with the extract since larval and pupal stages were compared to control groups (flies not exposed to the extract). Differences in behavior were assessed by video recordings and quantitative measurements. Flies exposed to the whole algal extract show a decrease in the phobic/aversive behavior characteristic of the OFA test and also decreases insomnia in food deprived flies. In conclusion though we have to further validate these preliminary results Sargassum platycarpum whole organic extract exerts anxiolytic-like effects in a Drosophila melanogaster model of anxiety.

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Perez-Otero, Joseph

Pérez, Joseph - Natural Sciences, University of Puerto Rico at Cayey; Dedrick, Rebekah - Biological Sciences, University of Pittsburgh; Rubin, MIchael - Natural Sciences, University of Puerto Rico at Cayey; Hatfull, Graham - Biological Sciences, University of Pittsburgh

Life Sciences

Requirements for Bacteriophage Growth: Using High Throughput Sequencing to Determine Gene Essentiality

Bacteriophages represent an absolute majority of all organisms in the biosphere and they are diverse organisms replete with novel genes, which do not have homologs in any database. To predict the function of these genes, it is useful to determine if the genes are required for growth of the phage, therefore Bacteriophage Recombineering of Electroporated DNA (BRED) was developed in the Hatfull laboratory (Marinelli et al., 2008) to construct targeted mutations in mycobacteriophages and determine the essentiality of genes for lytic phage growth. This method was used to determine the essentiality of 54 genes in mycobacteriophage Giles (Dedrick et al., 2013). BRED is an excellent tool for determining gene essentiality in bacteriophages, but it is expensive and time consuming. To solve this problem, an alternative high throughput method is being developed to study gene essentiality at a genome wide level. Using a strong mutagen, such as Ethyl Methanesulfonate (EMS), we expect to cause point mutations throughout a phage’s genome and then sequence the whole genome to determine which genes are essential for bacteriophage growth. Viable phages can only contain mutations in non-essential genes because mutations can never be found in essential genes that interfere with viability. Our aim is to heavily mutagenize phage populations with EMS to cause as many mutations throughout the whole genome, so that upon genomic sequencing and bioinformatics analyses, we can determine the gene essentiality of each gene in the bacteriophage genome.

Pérez-Rivera, Danilo T.

Torres Torres, Verónica L. - Natural Sciences Program, UPR-Cayey; Torres, Abraham - Natural Sciences Program, UPR-Cayey; Cruz Aponte, Mayteé - Department of Mathematics-Physics, UPR-Cayey

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Life Sciences

Development of a Computational Model of Glucose Toxicity in the Progression of Diabetes Mellitus

Diabetes mellitus is a progressive condition in which blood glucose levels remain abnormally high for prolonged periods. The two main chronic forms of this disease are Type 1 DM, characterized by the insufficient production of insulin, and Type 2 DM, characterized by an inappropriate resistance to insulin. Recent research has produced a variety of mathematical models that propose to accurately simulate dynamics between glucose, insulin, and pancreatic ?-cells throughout disease progression, however, very few maintain biological relevance due to unrealistic assumptions and insufficient parameter determination. We propose the development of a powerful model of disease progression, which will derive itself from biologically evidenced phenomena including the deposition of adipose tissue, the development of insulin resistance, and the gradual decay of ?-cell mass.

Pico-Torres, Arturo

Mateo, Zaira - Centro de Investigaciones Científica, PUCPR

Life Sciences

Anxiolytic effect of extracts from Passiflora edulis in Danio rerio (Zebra Fish)

A number of species of the genus Passiflora (Passifloraceae) have long been used in traditional folk medicines in many countries as a remedy to treat anxiety, insomnia, hysteria, epilepsy, spasm, ache and other illness. P. edulis is mainly the edible specie and isn’t commonly used as medical supplement like P. incarnata. The similarity between P. incarnata and P. edulis has impressed taxonomists as well as researchers. Specifically with P. edulis, experimental results from different research groups have brought some controversy. The Zebrafish (Danio rerio) has recently emerged as a model in studies related to genetics, neuropharmacology, behavior and good for anxiety and stress tests. Zebrafish possess neurotransmitters like dopamine, serotonin and glutamate. Suggesting that Zebrafish contains glutamatergic synapses as well other kind of synapses similar to

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humans. Here I present an experiment involving the use of Passiflora edulis and Danio rerio to study the possible anxiolytic effect. Three groups of Zebrafish will be used for the experiment. A control group and one group using a small concentration of ethanol for comparison with the experimental group, which will use the extract from P. edulis, prepared from dried parts of the plant. In this experiment we whish to confirmed presence or absence of an anxiolytic effect in P. edulis. The presence of anxiolytic effect is confirmed, it can open new possibilities for its use as a medical supplement and further studies in understanding the neurological process that lead to anxiety and other behaviors using the Zebrafish due to its homology with humans.

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Quinones-Vargas, Hector

Rivera-Rodríguez,Emmanuel - Biology, University of Puerto Rico (Rio Piedras); Baez, Marcel - Biology, University of Puerto Rico (Rio Piedras); Abramson,Charles I - Psychology, Oklahoma State University; Jiménez, Carlos - Biology, University of Puerto Rico (Medical Sciences); Agosto, Jose - Biology, University of Puerto Rico (Rio Piedras); Giray, Tugrul - Biology, University of Puerto Rico (Rio Piedras)

Life Sciences

Ih Current blocker ZD7288 feeding to honey bees causes changes in learning and memory.

Ih currents are mixed cation currents produced by Hyperpolarization-activated cyclic nucleotide channels (HCN). Ih currents are associated with the regulation of electrical activity in neurons, with effects including related to epilepsy and dopaminergic signaling. Honey bees represent a model where Ih current and behavior could be studied after pharmacological manipulations, since the honey bee HCN channel has been characterized for current kinetics, hyperpolarization activation, cyclic nucleotide regulation, and shown to be similar to the mammalian HCN channel. Biogenic amines like Dopamine (DA) (or Octopamine; OA) are known to modulate learning in insects. In order to study the effect of changes in Ih currents in the honey bee (Apis mellifera, sp.), we used ZD7288, an Ih blocker. We observed that indeed Ih blocker application is associated with changes in learning and memory of the honey bee. Using a place preference avoidance-conditioning assay, we found that changes in Ih causes significant changes in learning acquisition and does negatively influence short-term memory in honey bees. Using the proboscis extension assay, we found that Ih does not affect appetitive learning. These results, taken together support the hypothesis that Ih current is important for DA release. Our results on changes in learning, specifically in short-term memory, caused by Ih blocker, suggests an interaction between Ih current and dopaminergic regulation.

Raimundi-Raimundi, Antonio T.

Hernández, Marimar - Department of Biochemistry, UPR-School of Medicine, ; Duque, Maria Fernanda - Department of Biology, UPR-Rio Piedras; Rivera, Stephanie - Department of Biology, UPR-Rio Piedras; Noble, Gabriel - Department

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of Biology, UPR-Rio Piedras; González, Carlos I. - Dept. Biology, UPR-Rio Piedras; Dept. Biochemistry, UPR-School of Medicine; Molecular Sciences Research Building, San Juan, PR

Life Sciences

Role of p38 MAPK on Interleukin-3 Expression upon T-cell Activation

Interleukin-3 (IL-3) is a pro-inflammatory cytokine which is secreted by helper T-cells upon stimulation. It has been shown that IL-3 supports proliferation and differentiation of the myeloid cells. Deregulation of this cytokine has been implicated in chronic inflammation and has been found overexpressed in many diseases such as coronary artery disease, arthrosclerosis, schizophrenia, sickle cell disease, asthma and mostly in Multiple Myeloma. Its mRNA is expressed exclusively upon T cell activation. Previous results from our laboratory demonstrated that the post-transcriptional regulation of IL-3 depends on the presence of AREs (Adenosine and Uridine-Rich Elements) in the 3’ UTR of the mRNA. The p38 MAPK signaling cascade is an important part of the inflammatory signal and also in the regulation of ARE-containing mRNAs. These lead us to study the role of p38 in the regulation of IL-3 expression on activated T-cells. To test this, we used a specific inhibitor of p38 (SB202190). To mimic the immune-activation of Jurkat T-cells, we use phorbol-12-myristate-13-acetate (PMA) and ionomycin. mRNA levels and secreted human IL-3 protein of activated Jurkat cells were measured by RT-qPCR and Enzyme-Linked Immunoabsorbent Assay (ELISA), respectively. Cells were pretreated for 1hr with 10uM SB202190 and harvested after 0, 6, 12 and 24hrs of activation. Results demonstrated a significant decreased in mRNA and protein levels when p38 MAPK is inhibited. Altogether, these results suggest that p38 MAPK signaling pathway has an important role in IL-3 post-transcriptional regulation.

Ramirez-Rodriguez, Julyanas

Dr. Washington,Anthony - Biologia, Universidad of Puerto Rico; Hernandez, Liz - Biologia, Universidad de Puerto Rico; Dr. Jose Ramirez - Biología, Universidad de Puerto Rico en Mayaguez; Dr. Enrrique Melendez - Biología, Universida de Puerto Rico en mayaguez

Life Sciences

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Sobrevivencia de células cancerosas bajo el efecto de Ferrocenoyl 17b-hydroxy-estra-1,3,5(10)-trien-3-olate.

It has been found that transition metals such as cisplatin, are effective to kill certain types of cancer cells. The mechanism by which these compounds work is that the atoms of transition metals cling to the DNA of cancer cells disrupting DNA synthesis leading to apoptosis or necrosis. This research attempts to identify other compounds containing transition metals that induce mortality on breast cancer cells but do not affect healthy cells. In our studies we are comparing various functionalizations of ferrocene. In this complex, the ferrocene acts as the transition metal and the hormone estrogen or a derivative thereof, is used as a vector into breast cancer cells. To test the mortality of metastatic breast MDA 231 cells, the MTT assay was used; at different concentrations, from 1.3 uM to .009 uM, of a estrogen ferrocene. Our results suggest that the compound lowered survival in our cell population. The results were confirmed by a manual count that higher concentrations of the compound increase mortality. Implying that this compound is a possible candidate in breast cancer therapies. Future analysis will focus on improving MTT technique for better cell count. If continuous mortality is seen in a dose dependent way, we will proceed to induce tumors in mice and inject the compound in order to record its effects.

Ramos-Medina, Liorimar

Do Monte, Fabricio - Psychiatry, UPR-MSC; Manzano-Nieves, Gabriela - Psychiatry, UPR-MSC; Quirk, Gregory - Psychiatry, UPR-MSC

Life Sciences

Role of rodent infralimbic cortex during fear extinction

Failure to extinguish a fear memory results in a prolonged high fear state, which is a characteristic of many anxiety disorders and trauma- and stressor-related disorders. Animal models of fear conditioning represent important paradigms for the study of fear. Previous studies in rats have shown that the infralimbic prefrontal cortex (IL) is an essential region for the extinction of auditory fear conditioning. Accordingly, pharmacological inactivation of IL with muscimol before extinction training impairs extinction memory the next day, whereas electrical stimulation of IL evokes a low fear state. However, the techniques used in these studies lacked temporal precision to distinguish between extinction learning and extinction consolidation processes; and spatial precision to discern between cell bodies (somas) and fibers of passage.

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Furthermore, the exact role of IL during the extinction retrieval phase of auditory fear conditioning remains unclear. Here, we assessed the role of IL during extinction training (day 2) or extinction retrieval phases (day 3 or 10) of auditory fear conditioning. We found that silencing of IL with halorhodopsin (eNpHR) or inactivation of IL with F-mus before extinction training impaired the retrieval the following day, whereas these manipulations during extinction retrieval sessions had no effect. Taken together with previous studies, our results suggest that IL is necessary for learning of an extinction memory. However, activity in IL neurons does not appear to be critical during the extinction retrieval phase, suggesting that the extinction memory is stored in another region within the fear circuit (e.g. amygdala).

Ramos-Orta, Janesa

Frenández del Viso, Denny - Department of Biology, UPR-Humacao

Life Sciences

Photosynthesis and transpiration of endangered tree species, Goetzea elegans and Stahlia monosperma

In this project we are investigating the physiology of plants, and a key part of it, for growth and development, is carbon assimilation. The objective of this project is to characterize the photosynthetic capacity and gas exchange variables of endangered or threatened plant species, in order to produce information useful to select best growing conditions, and the effect of changing environment on the species. For now we selected Goetzea elegans and Stahlia monosperma species, which are endangered and threatened respectively. Measurements of photosynthesis, transpiration, internal CO2 concentration and conductivity were taken, on trees planted at the gardens of UPR-Humacao. To perform these measurements, we used a portable photosynthesis system LI-6400, which measures gas exchange in the leaves, with extensive control of micro-environmental conditions. So far we have managed to calibrate the system and implement a protocol for field measurements. We determined that both species have stomata only on the adaxial surface. Preliminary measurements on fully expanded leaves, exposed to sunlight, maximum photosynthesis values range between 4.8-11.5 ?molCO2/m2/s in G. elegans and 7.2-15.1 ?molCO2/m2/s in S. monosperma were obtained. Furthermore, G. elegans has values between 0.09-0.4 mol/m2/s for conductance, and 1.8-5.5 mmol/m2/s for transpiration. With S. monosperma we obtained values of 0.04-0.3 mol/m2/s for conductance, and 2.7-4.5

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mmol/m2/s for transpiration. This project will continue with the implementation of a protocol to measure light and CO2 response curves.

Rivera-Bonet, Charlene

Iqbal, Tania - Neuroscience, Michigan State University

Life Sciences

The Effects of Irritants in the Mouse Olfactory Epithelium Tissue

Our nose is the first line of defense against harmful irritants and pollutants. TRPA1 is a Transient Receptor Potential channel found on nerve fiber endings in the olfactory epithelium. TRPA1 plays an essential role in the process through which irritants promote neurogenic inflammatory pain within the olfactory epithelium. We hypothesize that TRPA1 is activated by environmental irritants which subsequently promotes neurogenic inflammation within the olfactory epithelium. Previous experiments showed olfactory epithelium cells responded to cinnamaldehyde with increases in intracellular calcium. However, it was not determined if this response was due to TRPA1 activation, or if it involved the activation of the tachykinin receptor NK-1 by released substance P. We performed live cell confocal calcium imaging studies to record changes in intracellular calcium. The TRPA1 inhibitor, HC030031, significantly reduced the cinnamaldehyde-evoked increase in intracellular calcium suggesting that calcium changes were initiated by stimulation of TRPA1. Activation of TRPA1 receptors on trigeminal nerve fibers can stimulate the release of substance P from these nerves and in order to confirm this, olfactory epithelium tissue was cultured in nitrocellulose membranes and treated with different cinnamaldehyde concentrations. Low cinnamaldehyde concentrations evoked Substance P release in the rostral nasal cavities, while high concentrations promoted release throughout the entire nasal cavity. Plasma extravasation, a symptom of inflammation, was measured by the application of capsaicin. Results showed plasma extravasation in the treated naris, and no plasma extravasation in the untreated naris. Through this study, we will have a better understanding of the mechanisms by which neurogenic inflammation occurs.

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Rivera-Cabrera, Melinnette

González, Alfredo - Biology, UPR-RIO PIEDRAS; Flores, Zomary - Biology, UPR-RIO PIEDRAS

Life Sciences

Study of gene expression under oxidative stress in Vibrio fischeri.

The squid Euprymna escolopes and marine bacterium Vibrio fischeri form a mono-specific mutualistic relationship. The squid host generates reactive oxygen species in response to V. fischeri. These species cause significant damage to cellular structures giving rise to oxidative stress. If the conditions of oxidative stress affects the expression of the genes oxyR1, oxyR2, and ahpC then its expression will vary depending on the growth phase and exposure to oxidants. To understand how this bacterium survives the oxidative stress, we generated transcriptional fusions of the oxyR and ahpC promoters to a lacZ reporter gene. oxyR and ahpC are part of the oxidative stress response in V. fischeri, oxyR encodes a hydrogen peroxide-inducible transcriptional regulator and ahpC is a peroxidase. The expression patterns of these genes were studied under different growth phases and exposure to oxidants. Results suggest that gene expression increases as bacteria grow and the superoxide generator, methyl viologen, does not affect the expression of these genes.

Rivera-Diaz, Maria

Matchett, Ashley - Natural Sciences and Mathematics

Life Sciences

Molecular Investigation into the Aetiology of a Skin Infection in a Puerto Rican Manatee

Recently a young manatee Trichechus manatus was found with an extensive persistent and antibiotic resistant skin infection. To determine the aetiology of this

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infection the contents of a pustule were sampled. Preliminary culture and biochemical tests of one of these samples shows a number of bacterial pathogens associated with Entereobacteriae principally Cedecea davisae a rare human pathogen. It is the purpose of this study to genetically characterize the bacteria isolated to determine the specific species sub species and whether this is evidence of either a human transmitted disease in manatees or a new manatee specific microorganism. Selective and differential culture techniques along with biochemical physiological and morphological analysis were conducted to determine bacterial species. Broadly the bacteria were differentiated into 7 Gram positive including Staphylococcus Streptobacillus Diplococcus and 5 Gram negative cultures predominantly Cedecea. To determine the exact nature and identity of the bacteria recovered DNA was extracted from the pure cultivars of the viable bacteria. The extracted DNA of these samples was assayed for the molecular identity using 16S rDNA specific sequence amplification PCR amplification. However 16S rDNA sequences lack the resolution to be determinative for species variations within the Entereobacteriae. For further specificity we utilized OriC and Tuf genes specific PCR. These were trialed with variable results and are currently undergoing further optimization. At the conclusion of these investigations the amplicons will be sequenced along with further PCR specific gene targets DnaJ Hsp40 GyrB rpoB and Hsp60 to improve phylogenetic resolution.

Rivera-Lopez, Frank

Coral Ramos - Department of Biology, University of Puerto Rico, Bayamón.; Barbara Avalos - Department of Biology, University of Puerto Rico, Rio Piedras.; Mariel Jimenez - Department of Biology, University of Puerto Rico, Rio Piedras.; Laura Mendez - Department of Physics, University of Puerto Rico, Rio Piedras.; Zuania Cordero - Department of Biology, University of Puerto Rico, Rio Piedras.; Jennifer Gil - Department of Biology, University of Puerto Rico, Rio Piedras.

Life Sciences

Bactericide Properties of Ag-GQD Nanocomposites

Functionalized silver nanoparticles coated with graphene nanostructures were synthesized by laser irradiation of benzene-silver colloid. The functionalization of this Ag-Graphene nanocomposite with polyethylene glycol provides stabilization and higher solubility in aqueous solution. The Ag-Graphene nanocomposite was characterized by UV–Visible spectroscopy, transmission electron microscopy (TEM), Raman spectroscopy, X-ray photoelectron spectroscopy (XPS), field

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emission scanning electron microscope (FE-SEM) coupled with energy dispersive spectrometry (EDS), and Fourier transform IR spectroscopy (FT-IR). The antibacterial activity of Ag-Graphene was tested using Pseudomonas aeruginosa and Staphylococcus aureus as model strains of Gram-negative and Gram-positive bacteria, respectively. The Ag-Graphene nanocomposite solution exhibits strong antibacterial activity against both types of bacteria, as tested using Kirby-Bauer assay disk diffusion and Minimum Inhibitory Concentration (MIC) assay. We hypothesize that by applying an external electric bias, a decrease in the bacterial inhibition time (less than 6 hrs) can be attained. The success of this method allows us to propose a mechanism which describes the bactericide effect in terms the ion transport in the solution when exposed to the bacteria. Taking advantage of the high biocompatibility of graphene and the antibactericidal activity of silver, the Ag-Graphene nanocomposite is a nontoxic biomaterial suitable for numerous applications, such as self-sterile textiles, biomedical devices, coatings, and cosmetics.

275

Rivera-Lugo, Rafael J.

Dou, Zhicheng - Department of Microbiology and Immunolgy, University of Michigan; Carruthers, Vernon B. - Department of Microbiology and Immunolgy, University of Michigan

Life Sciences

Mutational Analysis of a Putative Drug Resistance Transporter in the Human Parasite Toxoplasma gondii

Toxoplasma gondii is an obligate intracellular parasite that causes toxoplasmosis in animals and humans. At least 30% of the human population is infected. The infection can lead to lethal disease in immunocompromised individuals including AIDS and organ-transplant patients. No existing drugs are capable of eradicating the parasites from infected people. Opening new options, we recently reported that Toxoplasma parasites intercept host cytosolic proteins by funneling them into a lysosome-equivalent organelle termed vacuolar compartment (VAC) where they are digested. Additional work revealed that the VAC harbors a homolog of the malaria chloroquine resistance transporter (CRT). A single point mutation in CRT confers resistance to chloroquine treatment for malaria, profoundly impacting fatalities. Knocking out the CRT gene in Toxoplasma results in an enlarged VAC and reduced fitness. Topology analysis of the CRT primary sequence showed that four cysteine residues localize to a loop oriented in the lumen of the VAC. We hypothesized that these conserved cysteine residues function to regulate redox potential of the VAC and/or bind to metal ions to optimize the activity of VAC proteases. We performed site-directed mutagenesis to mutate these four cysteine amino acids to serine residues individually and introduce them into CRT-deficient parasites. We found that ?crtCRTC585S and ?crtCRTC596S did not restore the size of the VAC, and that ?crtCRTC609S did restored it but about 50% of the parasites showed mistrafficking of CRT. By identifying important conserved residues in a therapeutically relevant transporter this work forms a basis for future mechanistic dissection of CRT function.

Rivera-Rodriguez, Jaileen

Esteban, Ernesto - Fisica, UPR-Humacao

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Life Sciences

A Comparison Among Acrylamide Intakes in Prostate Cancer Patients from Dominica, Puerto Rico, Uruguay and Perú

A large percentage of the countries with the highest rates of prostate cancer mortality in the world are found in Africa and the Caribbean, and in lower rates in South America, with an exemption: Uruguay. Some risk factors that increase the chances of developing the disease are well known: age, genes, ethnicity and diet. Although between the Caribbean and Africa there may be a genetic influence that is causing these high prostate cancer mortality rates, what is the common factor between the Caribbean countries and Uruguay? We think that the risk factor in common between the Caribbean and Uruguay is diet. People from these countries consume foods mostly prepared at high temperatures, either roasted, fried or BBQ. Foods prepared at high temperatures release high amounts of acrylamide (a possible carcinogenic to humans). Acrylamide is a chemical that has only be found in high amounts in food prepared at temperatures above 120? C. In 2010, the EPA (Environmental Protection Agency) established that the maximum amount of acrylamide should be 0.002 mg / kg body weight of the individual. In this research, we have estimated for a man of 90kg born in Dominica, Puerto Rico, Uruguay, or Peru the levels of acrylamide consumed daily. Preliminary results indicate that foods consumed in the Caribbean and Uruguay exceeds the maximum acrylamide safe level, while in Peru they do not. These results are in agreement with mortality prostate cancer mortality rates published in the literature.

Rivera-Santiago, Dayanara

Rosado-Estrada, Lenulisy - Biología; UPR-Humacao; Reyes-De Jesús, Dalilah - Biología; UPR-Humacao; Álvarez-Del Valle, Jaylene - Biología; UPR-Humacao; Ríos-López, Neftalí - Biología; UPR-Humacao; Rodríguez-Vélez, Ileana

Life Sciences

The plains coqui (Eleutherodactylus juanariveroi) defense system: a bacterial-amphibian association with ecological and biomedical applications

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The plains coqui (Eleutherodactylus juanariveroi) is an endemic Puerto Rican frog. This coqui species dwells exclusively in the Sabana Seca wetlands and is the smallest within the 85 reported species in the Caribbean. Although it is only the third species in the genus with no direct parental care of eggs, their reproductive success is relatively high. The eggs of most coqui frogs do not hatch successfully if the male abandons the nest, as fouling of the eggs is often observed. However, this fouling is not observed in E. juanariverois eggs despite there is no direct protection as observed in other species. In addition, Batrachochytrium dendrobatidis (Bd), a chytid fungi associated with amphibian population declines and extinctions around the world, has been detected in the dryer margins of the wetland, but not inside the wetlands ecosystem where E. juanariveroi lives. Based on these observations we hypothesized that there may be something, perhaps microbial in nature that is protecting the eggs against fouling pathogens. We have performed various samplings in the wetlands in order to study the microbial diversity in this ecosystem. Until now, we have isolated ~70 microorganisms from the surrounding waters, plants, eggs, and frog skin (both male and female individuals). Three of these isolates have exhibited significant antimicrobial activity against Bacillus subtilis, Salmonella typhimurium and Shigellas sp.. Further investigation for the identification of other bacterial isolates with antibiotic activity, the identity of these antibiotic producing microorganisms and the secondary metabolites they produce are being addressed.

Rodriguez-Aponte, Carlos

Massey, Steven E.

Life Sciences

Mutation rates of cytoplasmic and mitochondrial ribosomal protein L1

Eukaryotic cells contain two different genomes inside them that code for proteins in the cytoplasm and the mitochondria, respectively. Based on the length of these, the Proteomic Constraint Theory proposes an inverse relationship between mutation rates and length, given that the longer the genome, the more mutations it will undergo, and so there will be a higher selective pressure to reduce mutation rates. This project will evaluate if the cytoplasmic and mitochondrial ribosomal proteins L1 act under this behavior by calculating the selective pressure on both proteins. It is expected that the selective pressure in mitochondria will be lower because the translation machinery in mitochondria is simpler, making the mitochondrial proteins

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more susceptible to mutations. Using bioinformatics tools, the sequences of the protein L1 from both genomes will be obtained and aligned. These alignments will provide information of changes in amino acid sequence in the protein. With information from Single Nucleotide Polymorphisms (SNP) database, data from the amino acids substitution will be recorded. A Ka/Ks ratio analysis will then be used to calculate the difference in selective pressure between nuclear and mitochondrial genomes. Calculated mutation rates can be used by future projects in Molecular Evolution and Comparative Genetics since it provides information on the evolution of a gene. They can also be used to compare different types of proteins and conclude which proteins may be more conserved because of negative selection in the gene.

Rodriguez-Deliz, Carla L.

von Trapp, Gardiner - Center for Neural Science, New York University; Mowery, Todd - Center for Neural Science, New York University; Kotak, Vibhakar C. - Center for Neural Science, New York University; Sanes, Dan - Center for Neural Science, New York University

Life Sciences

Auditory learning down-regulates inhibitory synaptic function in the sensory striatum

During associative learning a neutral sensory stimulus is paired with either an aversive event or a reward in order to establish an auditory-guided behavior. This type of learning may affect several regions of the brain such as the striatum. However, nothing is known about the role of the sensory striatum in auditory learning. To determine whether changes occur within the synapses as a consequence of auditory learning, we assessed inhibitory synaptic function in the sensory striatum because inhibitory networks control brain excitability. Gerbils between the ages of postnatal day 88 to 115 were trained on an amplitude modulation discrimination task since AM constitutes a core element of sound communication. On alternate days of training, we generated Corticostriatal brain slice preparations that preserved the ventral medial geniculate nucleus with its projections to the auditory cortex, as well as layer 5 projections into auditory recipient regions of the striatum. Spontaneous inhibitory synaptic currents and minimum evoked IPSCs were recorded in medium spiny neurons of the auditory striatum following a blockade of AMPA and NMDA receptors. Diminished amplitudes of both sIPSCs and mE-IPSCs accompanied learning an auditory task

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and lasted several days before returning to control levels. Changes in sIPSC amplitudes were also observed to significantly correlate with changes in task performance. Therefore, a transient period of disinhibition in the Medium Spiny Neurons of the auditory striatum could mediate auditory learning.

Rodriguez-Fernandez, Lucero

Drecia Rohena Ramos - Biologia, UPR-Humacao; Profesora: Wanda Rodriguez - Biologia UPR-Humacao

Life Sciences

Microbial quality assessment of beach sand at different locations in the eastern area of Puerto Rico

Beaches in Puerto Rico are a year around areas for recreation. Surveillance of water quality is observed in these recreational areas using fecal indicator bacterial standards to monitor water quality. Waters exceeding the standards are subsequently closed to bathers, however beachgoers are also in contact with beach sands and the sanitary quality of beach sand is not included within beach monitoring programs. Concern has been expressed that beach sand or similar materials may act as reservoirs or vectors of infection. Studies presented by the National Epidemiological and Environmental Assessment of Recreational Water in several years (2003-2005, 2007) revealed cases of health issues, particularly gastrointestinal problems, associated to beach sand quality. Studies in several areas of US and different countries has revealed presence and prevalence of human pathogens in the beach sand (Mohammed, et al., 2012 ; Pinto, et al., 2012 ; Sabino, et al., 2013). Our main goal was to assess the beach sand microbial quality with samples of different areas and conditions. Our preliminary results indicated presence of total and fecal coliforms, Staphylococcus sp., Enterococcus, among other bacteria in wet and dry beach sand samples in the two locations studied.

280

Rodriguez-Graciani, Keishla

Rodríguez, Keishla - Science and Technology, Inter American University of Puerto Rico; Aleno, Raul - Science and Technology, Inter American University of Puerto Rico; Miranda, Marco - Science and Technology, Inter American University of Puerto Rico; Delgado, Joan - Science and Technology, Inter American University of Puerto Rico; Diaz, Lourdes - Science and Technology, Inter American University of Puerto Rico; Ferrer, Edmy - Science and Technology, Inter American University of Puerto Rico

Life Sciences

Antimicrobial effect of improved antibiotics combined with Ni and Semi-Green Ag nanoparticles in Klebsiella pneumoniae

Bacterial resistance to antimicrobial agents is a major problem worldwide. The daily increase of resistant strains can trigger a variety of infections. Nanotechnology offers possible alternative treatments improving the antimicrobial activity of antibiotics due to the properties of different metals. Our main objective is to develop more effective treatments against these resistant bacterial and nosocomial infections combining metal nanoparticles with antibiotics. In this study two different nanoparticles Ni and Semi Green Ag were combined with antibiotics. The antibiotics Penicillin Amoxicillin Levofloxacin and Vancomycin were used at two different concentrations against Klebsiella pneumoniae ATCC 13882 the causal agent of pneumonia and urinary tract infections in humans. Also it revealed the antimicrobial effects of determined concentrations of antibiotics and nanoparticles at equal and different proportions against the bacteria. The results showed that some nanoparticles mixed with the antibiotics at specific concentrations increased the potential activity of the antibiotic against the bacteria while in others the nanoparticles mixed with the antibiotics decreased the potential activity of the antibiotics.

Rodríguez-Lopez, Julymar

Life Sciences

281

Light as a limiting factor in the growth and reproduction of the epyphyte Campylocentrum fasciola

Light is one of the most important factors in the growth and reproduction of plants. Even though epiphytes may seem to be continuously exposed to light, variation in the micro-environment could influence the growth and reproduction. In this case we evaluate the light's variation in the epiphytic leafless orchid Campylocentrum fasciola in an abandoned Guava farm. The objective is to find in any the relationship of light availability with the orchid Campylocentrum fasciola and if it is correlated with reproduction. We collected the Leaf Area Index (LAI) above 41 individuals and correlates it with the size of the plant and its production of fruits. The data was collected and utilizing an Concave Spheric Densiometer. To analyze the data we used the programming language "R". By tracing a lineal regression in the data, a tendency can be observed that relates the LAI with quantity of fruit.

Rodriguez-Martinez, Judith

Santiago-Berríos, Mitk’El - School of Science and Technology, Universidad Metropolitana; Vázquez-Quiñones, Luis - School of Science and Technology, Universidad Metropolitana; Nicholas, Hugh - Pittsburgh Supercomputing Center (PSC), Carnegie Mellon University

Life Sciences

Bioinformatics Characterization of Cytotoxic and Regulatory T-cell Molecule (CRTAM) to Identify Candidate Regions to Build a Nano-Biosensor for Prostate Cancer

Prostate cancer affects about 97% of men in the U.S. population. The American Cancer Society estimates that in 2014 there will be about 233,000 new cases and about 29,480 men will die of prostate cancer. Under- and overtreatment of patients are facts of current screening methods for prostate cancer. There is a need for a fast, precise and consistent diagnostic method. CRTAM (cytotoxic and regulatory T-cell molecule) is a biomarker gene found in aggressive prostate cancer which interacts with Necl-2 and provokes cytotoxicity by the Natural Killer Cells to destroy tumor cells. Our hypothesis is that a bioinformatics characterization will reveal unique DNA regions present in CRTAM, and those exclusive regions will be used during the construction of nano-biosensor for the detection of prostate cancer. We performed a bioinformatics characterization of five members of the Nectin-Like

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Family, including CRTAM, detect homologues using SSearch and BLAST searches at the European Bioinformatics Institute (EBI). A multiple sequence alignment (MSA) was generated with MUSCLE, motif identification by MEME, and specificity determining position (SDP) analysis using SDPfox. Two exclusive DNA regions in CRTAM were identified in the DNA MSA to be candidates’ sequences to build a nano-biosensor for prostate cancer detection. Five additional conserved regions in the CRTAM protein MSA were also identified, and will be considered for the construction of a nano-biosensor as alternatives. Based on these potential DNA candidates for the sensor, primers were designed using Primer3 and Primer Blast for future systematic construction and testing of the nano-biosensor for prostate cancer.

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Rodriguez-Martir, Keishla

Rullán, Osvaldo B. - Natural Sciences, UPR Aguadilla; Mayer, Robert J. - Natural Sciences, UPR Aguadilla; Tossas, Adrianne G. - Natural Sciences, UPR Aguadilla

Life Sciences

AVIAN SURVEYS IN COASTAL RESTORATION SITEIN CAMUY, PUERTO RICO

Coastal ecosystems in Puerto Rico have been threatened by human population growth. For instance, the coastal habitat in FincaNolla in the municipality of Camuy, has been heavily degraded by deforestation, the introduction of the exotic Australian pine (Casuarinaequisetifolia), and extraction activities for the construction industry. A restoration project under way in this site is substituting pine trees with native flora and promoting the formation of new sand dunes. The success of these practices is being evaluated using avian diversity as a bioindicator. Monthly surveys were conducted in native forest remnants and compared to pine forest from March to November 2014. A total of 40 species was recorded, 38 specieswere found in native forest and 28 in pine forest. The most common species in pine forest were generalists, such as the White-winged Dove (Zenaidaasiatica), Zenaida Dove (Zenaidaaurita), Greater Antillean Grackle (Quiscalusniger) and Bronze Mannikin (Lonchuracucullata). In contrast, native forest included these species, as well as endemics such as Puerto Rican Lizard Cuckoo (Coccyzusvieilloti), Adelaide’s Warbler (Dendroicaadelaidae), Puerto Rican Tody (Todusmexicanus) and Puerto Rican Woodpecker (Melanerpesportoricensis). Land overuse and forest fragmentation may be related to the high number of generalist and opportunistic species found in this site. However, the presence of unique forest species demonstrate the ecological importance of the coastal forest habitat in Finca Nolla, and thus suggests that the restoration practices will provide long-term benefitsto the avifauna by further improving and increasinghabitat availability.

Rodriguez-Merced, Nelson

Latorre Esteves, Magda - Chemical Engineering, UPR-Mayaguez; Stevens Sostre, Whitney - Biology, UPR-Mayaguez

284

Life Sciences

Microgravity Effect in the Tolerance of Toxicity by Excess Lipids in Yeast

With the rise in health diseases linked to obesity and the metabolic syndrome, such as heart disease and diabetes, it is becoming essential to find a viable alternative to reduce the public health burden these diseases cause. Free fatty acids (FFAs), which are formed as a result of lipid overload, can lead to lipotoxicity which can lead to cell dysfunction and cell death. Lipid droplets (LD) are the cellular organelle where FFAs are stored as neutral lipids. There is increasing evidence in the literature that LD expansion could have a protective effect on FFA-induced lipotoxicity. In microgravity conditions (e.g. spaceflight, modeled microgravity), cells from various organisms have been found to show an increase in LD formation. We hypothesize that in modeled microgravity conditions, cells will be able to handle the burden of excess FFAs through LD expansion. We are using Saccharomyces cerevisiae as a model organism because of its similarity with humans in the lipid metabolism. To induce lipotoxicity, oleic acid (OA) was used as a carbon source of food for the yeast cells. Media Supplemented with 0.1% OA was enough to induce a decrease in cell division, and to cause an increase in LD formation. Interestingly, results show that in modeled microgravity, yeast cells in normal growth media had a significantly greater amount of LD formation than the yeast cells in normal gravity were LD expansion was induced by adding OA.

Rodriguez-Ramos, Cesar

A. Rivera Serrano - Universidad Del Este; D. Álvarez - Universidad Del Este; J. L. Roig-López - Universidad Del Este

Life Sciences

The Effect of the Global Hypomethylation in the Differentiation and Commitment of In vitro Human Fetal Neural Stem Cells (hNSC).

It is imperative to have a clear understanding of how changes in the epigenetic status of a stem cell modify the gene expression profile that can result in an alteration in cell fate and determination. Stem cells are self-renewing, multi-potent cells characterized by their capability to differentiate. DNA hypomethylation affects biological processes related to cancer and relevant genes for pathogenesis of

285

neuroblastoma. In this project we used primary cultures of hNSC derived from discarded human neural, umbilical cord blood fetal tissue as a model system. With the purpose of studying how in vitro demethylation affects their gene expression profile, cellular commitment as well as differentiation towards neural or glial lineages. We hypothesized that DNA methylation will affect the in vitro differentiated cell population. Therefore, we conducted a series of experiments: 1) Double label indirect immunohistochemistry to stain the cells with glial (GFAP) and neuron (Beta tubulin III). 2) Image J software to quantify neuron and glial cells. 3) Real-Time PCR to analyze the expression levels of genes that are associated with glial linage differentiation. Results suggested that the treatment with the hypo-methylating agent 5-Aza-Deoxycytidine significantly decreases the percentage of neurons. However, a second sample shows no statistical difference on the numbers of neurons and glial cells between control and experimental. Also we observed a higher number of glial cells when treated with the agent. These results will help predict changes in the commitment and differentiation of hNSC and could be applied to the development of stem cell therapies.

Rodriguez-Sanchez, Paola

Diaz-Diaz, Lymarie - Biology, University of Puerto Rico Rio Piedras Campus; Flores-Cruz, Zomary - Biology, University of Puerto Rico Rio Piedras Campus; Delannoy-Bruno, Omar - Biology, University of Puerto Rico Rio Piedras Campus; Garcia-Arraras, Jose - Biology, University of Puerto Rico Rio Piedras Campus

Life Sciences

Antibiotic Effects on Intestinal Regeneration of the Sea Cucumber Holothuria glaberrima

Increasing evidence has shown that the gut microbiota plays important roles in the development and physiology of various organisms. The sea cucumber has a diverse intestinal microbiota that includes bacteria, fungi and unicellular eukaryotes. We are therefore interested in determining if the intestinal microbiota of the sea cucumber Holothuria glaberrima modulates the intestinal regeneration process. To achieve our goal we treated regenerating animals with a cocktail of antibiotics such as streptomycin, ampicillin, and kanamycin, to decrease the bacterial content. These were administered in a sterile manner every two days for a period of two weeks. We then used histochemical analyses to determine the antibiotic effect on intestinal regeneration as could be seen on the size of the regenerating intestine, the process of cell dedifferentiation and the degradation of extracellular matrix. Our

286

results suggest that after antibiotic treatment, the intestinal rudiment size in regenerating sea cucumbers was smaller than in animals that didn’t receive antibiotic treatment. Also, collagen degradation was disrupted in animals that received antibiotic treatment, as clumps of collagen fibers were observed in contrast to elongated fibers observed in untreated animals. In addition, an effect on cell dedifferentiation was observed in the mesentery of animals that received antibiotic treatment. Although further experimentation is required to determine if the microbiota plays a direct role in the process of regeneration our results strongly suggest that antibiotics can delay and disrupt the mechanism of wound healing and regeneration. Funded by NIH, NSF and University of Puerto Rico.

Rodriguez-Sosa, Nataila

Rodriguez, Eneric - Biology, Natural Sciences; Toledo, Ernesto - Biology, Natural Sciences; Garcias-Arraras, Jose E. - Biology, Natural Sciences

Life Sciences

Effect of Wnt Pathway Activation and Inhibition on the Intestinal Regeneration of the echinoderm Holothuria glaberrima

Wnt signaling is one of a handful of powerful signaling pathways that play crucial roles by controlling essential genes for embryonic development, homeostasis and regeneration. Molecular studies such as cDNA constructed library and in-situ hybridization performed in the echinoderm Holothuria glaberrima, a species known for its extraordinary regenerative capacities, have shown an overexpression of a homologue gene of Wnt. However, its possible function during the regenerative process remains unclear. In an attempt to elucidate this question, we studied the role of the Wnt pathway in the intestinal regenerative process of the H.glaberrima by means of Wnt pathway activation and inhibition. Regenerating intestines were treated both in vitro and in vivo with Wnt pathway activator lithium chloride (20mM) or inhibitor epigallocatechin gallate (50µM). Immunohistochemical analyses were carried out to observe cell proliferation, epithelial to mensenshymal transition cells, muscle dedifferentiation, and collagen degradation. LiCl-treated animals showed an increase in the size of the intestinal rudiment as well as in the number of dividing cells (via BrdU staining). For EGCG-treated animals a decrease in rudiment structure was observed. LiCl treated regenerating intestines also showed differences in muscle dedifferentiation. Our results suggest that the Wnt pathway is playing an important role in modulating mechanism during intestinal regeneration.

287

Rojas-Nieves, Virginia

Ramirez-Paz, Josell - Department of Chemistry, UPR- Rio Piedras; Griebenow, Kai - Department of Chemistry, UPR - Rio Piedras

Life Sciences

The effect of the signal peptide on L-asparaginase II secretion

L-Asparaginase II from E. coli is a tumor-inhibitory enzyme utilized in the treatment of acute lymphoblastic leukemia since the 1970s. The current FDA approved and commercially available formulations are purified from a “pool” of naturally secreted proteins expressed in E. coli under anaerobic conditions. Recombinant L-asparaginase II will shortly become part of the commercial asparaginase repertory due to the enhanced stability and activity it showed in many recent studies. For this reason, studies aimed at increasing the yield of this enzyme are extremely important. In this work we study whether the yield of recombinant L-asparaginase II is affected by a specific signal peptide, which is a short polypeptide responsible for exporting the enzyme to bacterial periplasmic space from where it eventually leaks into the medium. Three signal peptides were selected and their effect on L-asparaginase II secretion compared: the native L-asparaginase II signal peptide, a triple 2-4R mutant peptide, and the commercial Erwinia carotovora pe1B peptide. Each signal peptide will be cloned along with recombinant L-asparaginase II in the expression vector pET22b and finally secretion measured by determining asparaginase volumetric activity in E. coli cultures.

Rojas-Ortiz, Ivonne

Rojas Ivonne - biology; Rodriguez Concepcion - Biology

Life Sciences

288

Abundance of the zoea and megalopae larval stages in Caño Boquilla, Manatí

Most species of the subphylum crustacean have an important role in the global economy as they represent a food source for humans. The demography of the larval stages of crustacean could help us estimate the adult populations. Retention, dispersion and larval settlement strategies has evolved for different species depending on its habitat. A study about the abundance of the zoea and megalopae larval stages of the crabs in the families Grapsidae and Gecarcinidae was conducted. A 23 hour survey was conducted in Cano Boquilla, Manati, Puerto Rico. Larva samples were taken every hour as well as salinity and tide height readings. We found that the abundance of the zoea of the Grapsidae family was higher than the Gecarcinidae and that the abundance is related to the tide, salinity and time of the day. Megalopae were not identified to family, but showed the same temporal and spatial pattern as the zoea. The movement of larvae to shore and open ocean is determined by the tides and consequently salinity. Retention, dispersion and larval settlement strategies seem to be different for the two families. These differences could be due to time of the year, adult’s habitats and predators and maybe to abundance of adults of both families.

Rojas-Santiago, Stephanie

Ruiz Meléndez, Joshua M. - García Pérez, Marla C.; García Pérez, Marcos J.

Life Sciences

Taxonomy of Fishes Used as Bait on the East Coast of Puerto Rico

Most of the commercially important fish of Puerto Rico have been studied and the capture of some species has been regulated. However, the fish that are used as bait are captured without any restriction of quantity or season. The study of the resource for its conservation requires knowing what species are part of these captures. The objective of this work is to determine which fish species are being used as bait on the East side of Puerto Rico. In this investigation, until now, an amount of 209 specimens of fish have been collected, which were classified in 8 families and 17 species that are used as bait. Parts of the collection were donations from commercial fishers. Until now, 6 species of sardines, Clupeidae, have been identified which represents a 60% of the informed species for the Island and a total of 3 anchovies, Engraulidae. The fishes from these two families are the ones mostly used as bait. Other baitfish species, that appear in our collections, are from families

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Exocoetidae, Belonidae, Polynemidae, Sciaenidae, Sphyraenidae and Mugilidae. Finally, an identification essay was realized by using barcoding techniques -using the mitochondrial gen COI-. As a collateral result of the work, an illustrated taxonomic key was prepared for the Clupeidae family.

Roman-Rivera, Kharina

Life Sciences

Cuantificacion e identificacion de Sulforafano en los distintos tipos de Brassica oleracea var. botrytis por HPLC

El isotiocianato sulforafano es un compuesto que se encuentra en una amplia variedad de cruciferas del genero Brasicaceae, entre ellas la coliflor. Esta sustancia contiene propiedades anticancerigenas y antimicrobianas. El objetivo de esta investigacion sera cuantificar e identificar cual de los cuatro tipos de coliflores contiene mayor cantidad de sulforafano. Para la obtencion de la muestra se requiere llevar a cabo la conversion de glucorafanina a sulforafano, extraccion con diclorometano, purificacion del extracto en columnas de extraccion de fase solida, y deteccion por HPLC-UV para lograr los objetivos propuestos. Una vez concluido el proceso de experimentacion los resultados que se esperan obtener son que la coliflor morada presente mayor concentracion de sulforafano ya que, segun investigaciones realizadas, los repollos morados han presentado mayores concentraciones de la sustancia, lo cual se espera ocurra en la coliflor morada.

Rosa-Mercado, Nicolle

Rivera, Charlene - Biology, University of Puerto Rico-Cayey; Claudio, Patricia - Biology, University of Puerto Rico- Cayey; Montañez, Carolina - Biology, University of Puerto Rico- Cayey; Rivera, Valeria - Biology, University of Puerto Rico- Cayey; Rubin, Michael - Biology, University of Puerto Rico- Cayey

Life Sciences

290

PCR Amplification, Cloning, Sequence Determination, and Bioinformatics Analyses of Plant GAPDH Genes

Glyceraldehyde-3-phosphase dehydrogenase (GAPDH) is a family of housekeeping genes that catalyze a reaction in glycolysis, a metabolic pathway that turns glucose into pyruvate during cellular respiration. There are eight different GAPDH genes throughout the Arabidopsis thaliana genome. Characterizing the GAPDH genes from different plants is important for studying the evolutionary relationship between this family of genes. The specific aims of this project include extracting genomic DNA in order to PCR amplify GAPDH genes using specific primers, cloning and sequencing these genes, and analyzing the data using bioinformatics tools. We have selected different plants that are either endemic to Puerto Rico or have medicinal or economic value. These plants include Annona muricata, Bixa orellana, Mormodica charantia, Petiverea alliceae, and Polygala cowelli. After extracting their gDNA, we cloned the PCR amplified products for P. alliceae and P. cowellii into a pJET vector and sequenced them in order to determine their identity. BLAST similarity analysis confirmed that the cloned genes from each of these plants belong to the GAPDH gene family. These genes were annotated using 4Peaks, CAP3, BLAST, Transeq, and SixPack. Future work includes isolating genomic DNA and cloning of GAPDH genes from Annona muricata, Bixa orellana, Mormodica charantia, and as well as other important plants. The final annotated sequences for P. allicieae and P. cowellii will be deposited into GenBank, the international DNA sequence database. These experiments increase our understanding of plant GAPDH genes and their encoded protein products.

291

Sanchez-Irizarry, Gabriel

Hendricks, Timothy - Department of Natural Sciences and Mathematics, Interamerican University of Puerto Rico Bayamon Campus

Life Sciences

GENETIC EXPRESSION ANALYSIS OF RALDH2 AND EPHA6 IN MURINE SPINAL CORD

Neuronal and axonal development is crucial to the formation of the complex framework underlying the formation of the vertebrate nervous system. Neurons have the capacity to interact with other cells during embryonic stages to direct their migration and extension. The assemblage of neurons takes place within the growing neurites; these appendages fall into two categories, axons and dendrites. The tip of a growing neuron is called the growth cone. This structure is responsible for guiding outgrowth by detecting intercellular signals (Price et al., 2011). The protruding growth cone contains Ephrin A receptors that have been shown to determine axonal guidance. The binding of ephrin-As to EphA-receptor-expressing axons is ‘chemorepulsive’, in that it induces actin bundling, and axon retraction (Feldheim et al., 2004). Raldh2 encodes for an enzyme that converts retinaldehyde to retinoic acid (RA). Diffusion of the RA morphogen has also shown the capacity to control gene expression through gradient binding of RA nuclear receptors. The research objective is to analyze the genetic expression of EphA6 and Raldh2 in the developing murine spinal cord. Selected sequences for each gene were amplified using PCR and purified. The amplicon was ligated to p-GEM-t-ez vector and cloned onto electrocompetent Escherichia coli cells. Nested colony PCR was conducted to determine orientation and presence of selected insert within prepared construct. Selected purified constructs will be sequenced and In situ hybridization using digoxigenin labeled riboprobes will be conducted to obtain a visual colorimetric expression pattern in murine embryonic spinal cord of Raldh2 and EphA6 genes.

Sanchez-Ruiz, Jose

Kelly, Sean - Department of Bioloy, University of Puerto Rico, Rio Piedras; Ramirez, Alonso - Department of Environmental Sciences, University of Puerto Rico, Rio Piedras

292

Life Sciences

THE EFFECT OF URBANIZATION ON THE WEB SPINNING BEHAVIORS OF RIPARIAN ORB-WEAVING SPIDERS

Urban streams are known to be heavily impacted by elevated concentrations of nutrients and pollutants. These aquatic ecosystems not only represent a source of energy for riparian consumers, but also a source of contaminants through bioaccumulation from consuming emerging aquatic insects. The web-building behavior of spiders has been used as a bioindicator for environmental contaminants due to changes in web features that can be linked to neurological effects caused by pollutants. In this study we evaluated the effect that urbanization, and its possible associated pollutants, have on the web-building behavior of Tetragnatha boydi. Tetragnatha is a genus of web-building spiders known to be specialists of aquatic ecosystems and are major consumers of aquatic insects. We selected five study sites along an urban gradient within the Río Piedras watershed in San Juan, Puerto Rico. Webs were photographed in the field and we later analyzed web structure variables (e.g., radii length, capture spiral length). We found significant differences for some web parameters among different sites, which indicate possible effects from contaminants associated with differences in surrounding urban density.

Santiago-De Veer, Albert

Velázquez García, Leened M. - Natural Sciences, Inter-American University of Puerto Rico, Bayamón Campus; González Irizarry, Yomarie I. - Natural Sciences, Inter-American University of Puerto Rico, Bayamón Campus

Life Sciences

Deforestation in Urban Areas of the Municipalities of Bayamón, Puerto Rico

Our objectives are: to determine the extent of deforestation in the urban areas of Bayamón, determine what species of trees are the most cut down and the approximate age of the cut down trees. Nine urban developments were observed in the municipality of Bayamón. Pictures were taken of the trees trunk found in the public area (between the sidewalk and the street). Root system and stems were

293

analyzed to identify the species of tree to which the trunk belonged. Dendrobiology was used to determine age of the tree at the moment was cut down. A total of 237 tree trunks were analyzed. The following species of trees were identified: Melaleuca quinquenervia, Swietenia mahagoni, Tabebuia aurea, Bucida buceras, Albizia procera, Callistemon sp., Lagerstroemia speciosa and Ficus sp. A 46% of the tree trunks were identified as Melaleuca quinquefolia with an average age of 15 years per tree. This specie was primarily found in one urban area located at the south of Bayamón. A 31% of the tree trunks corresponded to Swietenia mahagoni, with an average of 14 years per tree. This specie was found distributed in all urban areas studied except one. An 8% of the total specimens found were palm trees trunks. The cut species were found to be not suitable for urban areas due to their root system and the height they can reach. Education to the public is recommended to select the right trees for the right place according to size and growth characteristics.

Santiago-Rivera, Edgardo

Ackerman, James D. - Biology, University of Puerto Rico- Rio Pieras

Life Sciences

Is Orchid Fitness Related to Phorophyte Selectivity?

Is fitness in epiphytic orchids related to phorophyte selectivity? We tested the hypothesis in four species of native to Puerto Rico: Plerothallis ruscifolia, Pleurothallis pruniosa, Mormolyca pudica and Jaquinella globosa. The research was done at El Yunque National Forest, in El Verde Field Station. For each orchid species we established 30 plots, which consisted of target tree with an orchid and three nearest neighbor trees up to 3 meters of the target tree. Our sampling regime included both vegetative and reproductive components of fitness: leaf length and width and the number of flowers and fruits. We then correlated this data, with selectivity index, based on presence and absence of orchid species in a given tree species. Spearman rank correlation tests failed to show any significant relationship between fitness and phorophyte selectivity. We then pooled the data for all four orchids, and ran a Principal Component Analysis, which shows that all four species generally selects the same tree species, with three selection most different by J,globosa. However we did not find significant correlations between fitness and host species selectivity. When we categorized host tress as good host or bad host we found that there was a significant difference in fitness, but opposite from what was expected. Host trees that are the best for orchid establishment, are not best for reproductive fitness.

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Santos-Rivera, Aixa

Kristin Ocasio - Biology, Universidad de Puerto Rico Bayamon; Acevedo Charry, Orlando - Graduate, Universidad de Puerto Rico Rio Piedras; Aboukheir, Mahmoud - Escuela de Salud Publica, Universidad de Puerto ; Burgos Rodriguez, Jhoset - Escuela de Derecho, Universidad de Puerto Rico; Ackerman, James - Biology, Universidad de Puerto Rico Rico Piedras

Life Sciences

The Mammals (Mammalia) housed in the Zoological Museum of the University of Puerto Rico at Río Piedras (MZUPRRP-M)

A zoological museum is a public or private institution that conserves, researches, communicates and exhibits organism collections belonging to the Kingdom Animalia. These collections are essential tools in many investigations and are also of great educational value. The Zoological Museum of the University of Puerto Rico at Rio Piedras campus MZUPRRP was established in the 1960s. It has approximately 70,000 specimens, ranging from: amphibians, reptiles, mammals, mollusks, arachnids, among others. The MZUPRRP has: 1 an alcohol preserved collection containing several specimens of bats captured in Puerto Rico; 2 a taxidermy collection containing mostly rodents; 3 a bone collection including diverse marine mammals. These collections were organized by phylum, class, order, family, genus and species using digital encyclopedias such as Encyclopedia of Life EOL and International Union for Conservation of Nature IUCN. GBIF data base Global Biodiversity Information Facility was used to organize each specimen collection, a catalog number was assigned to each specimen to organize and easily retrieve them in the museum. The purpose of GBIF is to provide access via the Internet to biodiversity data worldwide to support scientific research, promote biodiversity conservation and promote sustainable development. The most important information that can be found in the database is the species systematic and nomenclature information, the date of collection, the collector's name, collection locality, among others. I Georeferenced each specimen by locating it on a map and recording its geographical coordinates. The tools used for this technique were Google Earth and Quantum GIS. Georeference data are especially important to measure population dispersal and migration though time. Partial results indicate that the collection has 157 specimens distributed among 24 families, 38 genera and 48 species of mammals. The three most common families are Soricidae, Phyllostomidae, and Trichecidae. The three most common genera are Blarina, Peromyscus, and Trichechus. Endemic taxa found in the mammal collection include

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the bats Molossus fortis and Monophyllus redmani portoricensis. The oldest specimen was collected in 1925 and the most recent is from 2014. MZUPRRP has specimens from upper Canada, the Caribbean Islands to upper South America. Our museum is not only an invaluable repository of knowledge for scientists, but it is also a significant resource to teach all aspects of zoological diversity in interactive and creative ways to students of all ages.

Selles-Perez, Luis

González Bermúdez, Yomaries - Natural Science, UPR-HUMACAO

Life Sciences

Reproductive success indices in the epiphytic and leafless orchid Campylocentrum fasciola (Lindley) Cogniaux

In most plants there is a relationship between the size of the organism and their reproductive success. In leafless plants, it is not clear what are the morphological variables which are correlated with reproductive success. In the case of leafless plants, the role that the roots play can be considered more crucial, because they are also responsible for photosynthesis. To evaluate if, and which, morphological variables are correlated with reproductive success in leafless plants we studied the plant Campylocentrum fasciola, an epiphytic orchid. We evaluated the relationship between the number of roots and the length of the longest root on the fruit production in over 100 individuals. We found a positive relationship between both: the number of roots versus the amount of fruits, and the length of the longest root versus the amount of fruits. In leafless plants, the length and the amount of roots are indicators of potential reproductive success.

Soto-Gonzalez, Fidel

Planas Rivera, José M - UPR Aguadilla

Life Sciences

296

Determination of RFLP Patterns of the 16S rRNA Gene of Halobacteria from Guánica Salterns.

Halobacterias are Archaeas that thrives in high salt concentrations. Very few members of the Halobacteria are known at present time. We isolated a Halobacteria in Guánica Salterns, and we are in the process of identify and characterize it using molecular tools. Our problem is to determine if it is one of the species of halobacteria already described in Puerto Rico or is a new one. We hypothesize that is a new halobacteria, based on previous protein and biochemical profile data realized in our lab. We are using RFLP of the 16S rRNA gene as indicator and comparing the patterns with the patterns obtained from Halogeometrium borinquense, Haloferax mediterraneii, and Halobacterium salinarum. 16S rRNA gene primers were designed to amplify the gene using PCR. Purification and integrity was confirmed by agarose gel electrophoresis. RFLP patterns obtained with restriction enzymes ApaI, HaeIII and MluI will be presented and analyzed. Combining PCR-RFLP techniques we have been able to characterize molecularly the Halobacteria isolated in Guánica Salterns.

Torres-Gutierrez, Cesar

Shalita, Chidyaonga

Life Sciences

TTHERM_00930810 and its Role in Tetrahymena

Tetrahymena is a protozoan common in freshwater ponds. This protozoan has been studied for years and serves as a great model organism. Regardless of its popularity, there are genes whose function has not been studied thoroughly. In this project, we aim to discover the function of the gene TTHERM_00930810 and contrast it with analogous genes in other species. The methodology that we used involves TOPO Cloning, L-R Recombination Reactions, Electroporation and Fluorescence Microscopy. We found that the gene TTHERM_00930810 is analogous to genes found in Dicentrarchus, Mus musculus, Xenopus laevis, Homo sapiens among others. The proteins TTHERM_00930810 encodes are part of the Cullin Family Proteins which are involved in the universal process of Ubiquitination; alteration or drgradation of proteins. This finding grants us a known gene in a very popular and inexpensive model organism which can be used in the study of Ubiquitination.

297

Valentin-Acevedo, Antonio J.

Valentín-Acevedo, Javier A. - Natural Siences Deparment, UPR-Aguadilla; Cintron-Gerena, Manuel - Natural Siences Deparment, UPR-Aguadilla; Planas-Rivera, José M. - Natural Siences Deparment, UPR-Aguadilla

Life Sciences

Molecular Characterization of Guánica Salterns Halobacteria by Total Protein Profile Analysis

Halobacteria are members of the Archea domain, and they live at high salt concentrations. There are few halobacterias describe in the literature, and two new species were described in Cabo Rojo Salterns in Puerto Rico. Our lab isolated a halobacteria in Guánica Salterns and we are addressing the following question. Is this one of the halobacteria already described or it is a new one? We hypothesized that it is a novel bacteria. Preliminary results including morphology analysis, staining responses, biochemiclal analysis and antibiotic susceptibility analysis suggest it is a novel halobacteia. To further pursue our task, we are characterizing it by molecular analysis, and comparing the results with the results obtained from Halobacterium salinarum, Haloferax mediterraneii and Halogeometricum borinquense. Total protein isolation was carried out by TCA and acetone precipitations, protein concentrations were determined by BCA assay and SDS-PAGE for total protein was carried out. Our result shows the range of their protein and comparison between them will be presented.

Vargas-Zapata, Valerie Y

Taveirne, Michael E. - Microbiology & Immunology , University of Michigan, Ann Arbor; DiRita, Victor J. - Microbiology & Immunology , University of Michigan, Ann Arbor

Life Sciences

298

The role of TarA in the regulating physiological and transcriptomic responses of Vibrio cholerae

Vibrio cholerae is a gram negative bacteria that causes the diarrheal disease cholera. Most cases of cholera are due to consumption of contaminated water and food and the disease is endemic in many developing countries where water quality measures are lacking. V. cholerae possesses two major virulence factors required for causing disease: cholera toxin, and toxin-coregulated pilus which is controlled by the ToxT transcription activator. ToxT binds to specific promoter sequences known as toxboxes. Previous work identified a toxbox sequence from which ToxT directs transcription of a small RNA (tarA). TarA was demonstrated to control glucose uptake by negatively regulating expression of ptsG, a major glucose transporter. We hypothesize that there are other targets of TarA regulation. To test this, we used a deep-sequencing based transcriptomic approach called RNAseq, to compare expression of cellular RNAs in a V. cholerae strain expressing tarA (WT VcO395), and a mutant strain lacking tarA (O395?tarA). RNA was isolated from cells grown under toxin inducing conditions (LB pH 6.5, 30°C). cDNA libraries were prepared and sequenced. To complement our RNA profiling study, we assessed growth profiles of wild type and tarA mutant strains grown with multiple different substrates. We observed transcripts differences related to amino acid biosynthesis (ilvY, argF), sugar transport (mshD, manA), and metal transport (znuACB). Additionally, we observed growth differences corresponding to sugars (glucose, glycerol, and fructose) and amino acids (glutamic acid, proline, and aspartic acid). Our results suggest that TarA may be involved in regulating other transcripts involved in many metabolic processes.

299

Velazquez-Garcia, Leened

Hendricks, Timothy - Natural Sciences, Inter-American University of Puerto Rico

Life Sciences

Molecular Cloning of BASP1

A population of commissural inhibitory interneurons known as dI6 is an important component of the spinal cord neural circuitry that governs locomotion behaviors in mammals. A Zn finger transcription factor known as Wilm’s tumor homolog 1 (Wt1) is expressed in newly differentiated dI6 interneurons. Additionally loss-of-function studies have demonstrated that Wt1 function is required for appropriate differentiation of dI6 interneurons. In order to better understand the molecular mechanisms of dI6 interneuron differentiation we propose to study the expression of brain acid soluble protein 1 (BASP1) in the murine spinal cord during neurogenesis. It is known that BASP1 serves as a transcriptional co-repressor in DNA-binding complexes that also contain Wt1, however this has not been demonstrated in the developing neural tube. The present work will test that hypothesis that Wt1 and BASP1 are co-expressed in dI6 interneurons. Primers were designed in order to amplify a specific sequence of the gene, which will be cloned into a vector (pUC19). Once these cloning steps are complete, the recombinant construct can then be utilized to produce antisense riboprobes with incorporated digoxigenin UTP and perform in situ hybridization on tissue sections of embryonic spinal cord to verify co-expression with Wt1.

300

Mathematics

301

Betancourt-Velez, Fernando

Stotts, Ontario - Wake Forest University ; Yang, Joyce - Harvey Mudd College

Mathematics

ISOMORPHY CLASSES OF TRIVOLUTIONS OVER SL(2,K)

Involutions of real matrix groups have been used to construct real symmetric spaces for more than 100 years. Using automorphisms of order n of matrix groups de- ned over an arbitrary eld k one can construct spaces similar in nature. These are called generalized symmetric spaces. As a rst step in the study of these generalized symmetric spaces we consider trivolutions of SL(2; k).Trivolutions are group automorphisms of order 3. SL(2; k) is the group of 2-by-2 matrices with determinant 1. In this paper we will give a characterization for the isomorphy classes of trivolutions of SL(2; k) with k any eld of characteristic not 2 nor 3. This work is analogous to one that was made by my research mentor Aloysius Helminck and one of his Ph.D students Wu on automorphism of order 2.

Morales-Miranda, Adriana

Mathematics

An Investigation Into Fully Homomorphic Encryption Scheme and Applications

The well known RSA public key crypto system discovered in 1978 allows only multiplication and division on encrypted data. Craig Gentry has recently discovered a Fully Homomorphic Encryption Scheme that allows all operation on encrypted data. We present an investigation into this fully homomorphic scheme and present some applications.

302

Perez-Santiago, Roberto

Aguirre, Sebastiani - Department of Mathematical Sciences, University of Puerto Rico - Mayaguez; Suazo, Erwin - Department of Mathematical Sciences, University of Puerto Rico - Mayaguez

Mathematics

On the Cauchy Initial Value Problem for General Linear Diffusion and Schrodinger Type Equations

In our research we used a method introduced by Suslov et. al. in 2008 to solve the Cauchy initial value problem for general linear diffusion and Schrödinger type equations. With help from Riccati type non-linear differential equations with known solutions we were able to construct general closed-form solutions that can be used to solve classical examples presented in any standard partial differential equations (PDE) class. Some of the aforementioned closed-form solutions would probably be impossible to obtain by any of the standard methods taught in a PDE class. This was achieved by coding our method in both Maple and Mathematica. We will also discuss how our research can be applied to cancer treatment.

Rivera-Rodriguez, Eric L.

Rivera Rodriguez, Eric L. - Mathematics Sciences, University of Puerto Rico Mayaguez

Mathematics

Factorizaciones Amigas Atomicas

En la XXIII Olimpiada Colombiana de Matemáticas y V Olimpiada Bolivariana de Matemáticas, nivel intermedio, se definen los números amigos como dos enteros positivos cuyo producto es un cuadrado perfecto. A raíz de esto, “amigo” se convierte en una relación de equivalencia. En este trabajo se denota la relación amigo como y estudia las t-factorizaciones o los t-productos de los enteros, las

303

cuales llamamos factorizaciones amigas. Es decir, dos enteros distintos de cero y de se permiten multiplicar si y solo si son amigos. Se caracterizó cuando un elemento distinto de cero y de , tiene una t-factorización no trivial. Presentamos resultados con respecto a la relación y algunas herramientas para poder entender las t-factorizaciones no triviales.

Rosado-Perez, Michelle

Mathematics

Reduced ?_n-Irreducible ?_n-Factor Graphs

A nonzero nonunit integer x has a ?_n-factorization if x= ±1 x_1?x_2?x_k where for each i?j n?x_i-x_j. We also say that x is a ?_n-product of the x_i and each x_i is a ?_n-factor of x. We called x a ?_n-irreducible, if k=1. In 2011, Ortiz and Lucena defined a ?_n-irreducible ?_n-factor graph of x, as a graph in which the vertices represents the ?_n-irreducible ?_n-factor (up to associates) and two vertex are connected if there is an ?_n-factorization into ?_n-irreducible where the ?_n-irreducible ?_n-factor associated with such vertex appear in such ?_n-factorization. This work extend the idea of the ?_n-irreducible ?_n-factor graph, that is, when the factor “±” in front of the ?_n-factorization cannot be used. We defined, the reduced ?_n-irreducible ?_n-factor graph, in a similar manner the only difference from the ?_n-irreducible ?_n-factor graph is that associates of a reduced ?_n-irreducible ?_n-factor cannot be represented by the same vertex. We present preliminary results of a characterization for such graphs when n=0,1,2 and 3. They are distinct with respect to the ones Lucena and Ortiz characterized in 2010.

304

Physics

305

Carradero-Santiago, Carolyn

Merced Sanabria, Milzaida - Vedrine-Pauleus, Josee

Physics

Using COMSOL Multiphysics Software to Analyze the Thin Film Resistance Model of a Conductor on PET

In this research work, we are developing a virtual model of a thin film to analyze the electrical conductivity and properties of organic solar devices. The thin film is composed of three layers, polyethylene terephthalate (PET) as the substrate, a second layer of graphene, which we using for its flexibility and its highly conductive, unlike the indium tin oxide (ITO) that are used normally and the third layer consists of poly(3,4-ethylenedioxythiophene)-poly(styrenesulfonate), PEDOT:PSS. The construction of the cell is based on a sandwich structure, which means that the materials are going to be placed layer by layer individually with specific parameters and characteristics for each material, such as Young’s Modulus, Poisson’s ratio, thermal expansion, heat capacity. COMSOL Multiphysics is the software I am using to develop the virtual model and to analyze the thin-film layers. This program is very complex, and precise in terms of characteristics and learning to use it consisted of a great amount of my work and time this semester. The first two layers were already built when I started the project and as part of continuing building up the thin film, we worked on the next layer, PEDOT:PSS. Currently, we are researching the remaining characteristics of this material and plan on moving to the next layer. Since COMSOL Multiphysics is very specific, we are being meticulous in reading the reference papers to get a realistic representation. We are looking for correlation with the experimental data obtained in previous research and as a future goal to vary the parameters of the whole cell in order to obtain the ideal fabrication conditions for the devices.

Corchado-Albelo, Marcel

Mendez, Hector - Physics, UPR-MAYAGÜEZ ; Sepulveda, Elba - N/A, CROEM; Hernandez, Michael - N/A, CROEM; Gimenez, Gilberto - Electric Engineering, UPR-MAYAGÜEZ

306

Physics

Cosmic Ray interaction with Earth's Magnetic Field

Cosmic Rays are electrically charged particles, mostly protons and atomic nuclei, thought to originate from black holes or supernovas—but researchers have still to discover their origin—arrive at Earth’s magnetosphere, therefore disturbing the Earth’s magnetic field with their charges. After entering the Earth’s atmosphere, the Cosmic Ray decay into subatomic, with the molecules found on air, particles known as Pions, mesons, later on decaying into particles known as Leptons including the Muon (µ), which because of have a lifetime approximately of 2.20 microseconds. Even with speed approximate to c (speed of light) from the far distance in which Muons begin to exist, they would never reach the Eath surface, which they do, but do to Special Relativity and concepts known as Time Delay and Length Contraction, which occur at speeds close to c (3 x 10^8 m/s), at their own reference frame. Most of this Muon's decay the Earth’s oceans. Upon hitting the oceanic surface the Muon would contaminate the Earth’s oceans with their electromagnetic charge. This induces transfer of the electric force from the Muon to the surface in contact’s electromagnetic field, Earth’s oceans water.

del Valle-Rodriguez, Yashira M.

Muller,Rafael - Physics, UPRH; Cersosimo,Juan - Physics,UPRH; López, Andy - Physics,UPRH; Vergara,Nelson - Physics,UPRH; Martínez,Luis - Physics,UPRH

Physics

Mesuring and positioning the angle of binary systems

The purpose of this investigation is to obtain data of position angle and separation of binary stars systems observed twice a year. The data is gathered at the 31 inch National Undergraduate Research Observatory (NURO) telescope at the Anderson Mesa location of Lowell Observatory, 20 miles east of Flagstaff, Arizona. This telescope allow us to take images using the NASACAM CCD camera with27-micron pixels, a field of view of 16'x 16'and a plate scale of .456 arc seconds/pixel. After collecting the data, the standard procedure involves the use of pixels for direct measurement of both position angle and separation, also the calibration of the images through flats and bias. The data obtained is suitable for insertion in the U.S. Naval Observatory (USNO) - Washington Double Star Catalog.

307

Espinosa-Rodriguez, Gabriela Lynnette

Muller, Rafael - Physics, UPRH; Cersosimo, Juan C. - Physics, UPRH; Lopez, Andy J. - Physics, UPRH; Vergara, Nelson - Physics, UPRH; Martinez, Luis - Physics, UPRH

Physics

Mesureament and calculation of Binary Star using a 31 inch Schmidt-Cassegrain Nuro Telescope

Our job it’s to measure Binary Stars selected by the Washington Double Star Catalog. The data that we receive comes from a 31 inch Schmidt-Cassegrain Nuro Telescope from Flagstaff, Arizona. This 31 inch Schmidt-Cassegrain Nuro Telescope was built by AstroMechanics. Following the standard procedure to calibrate the images, we pixelize the images to measure the separation of the Binary Stars system also measuring the angle of the star system. We use a software to check our results for any error. Then our data it’s published at the Washington Double Star Catalog. This research project is part of the ongoing data gathering investigation that has been active from several years.

Falcon-Garrido, Jorge

RUIZ, ANGEL R - PHYSICS, UPR-RIO PIEDRAS; FONSECA, LUIS F - PHYSICS, UPR-RIO PIEDRAS

Physics

Semiconductor Magnetic Nanowires: Synthesis and Characterization

We report the synthesis of FeMnSi nanowires via chemical vapor deposition (CVD). Nanowire thickness ranges between 100nm and 200nm. Presence of manganese

308

was confirmed through EDS characterization. Magnetic characterization using VSM indicates that the nanowires possess a remnant magnetization of 2x10-3 emu at room temperature. Electrical testing indicates semiconductor behavior with resistances of ~307? at 130K, and ~282? at 282K. Comparison between these nanostructures and Mn-ion implanted FeSi samples is discussed.

Feng, Siyuan

Physics

Characterization of nanostructured tungsten oxide for the development of a prototypic gas sensor

Gas sensors are detection devices containing sensing materials that change when a particular gas is sensed. In this investigation, after tungsten oxide was synthesized using CVD, this material underwent various experiments to study its electrical variations in different conditions. Through microscope use, it was determined that the material was wire structured. Additionally, through the construction of an electric circuit, the voltages suitable for the sensing materials’ operation were found to range between 6V and 15V at three different temperatures. After that, a prototype of WO based sensor was designed, fabricated and tested. The experiment data clearly indicated that the obtained sensor had a high sensitivity to gases hydrogen and methanol. The results of the investigation suggested that the formed tungsten oxide could be used as a sensing material. Further investigation concerning sensing aspects as time response, selectivity, and stability as well the enhancement of sensitivity is needed achieve extreme high sensitivity of gas sensors for commercial application.

Irizarry-Del Toro, Reniel

Physics

Data Collection and Analysis of Atmosphere Cosmic Rays

309

Cosmic rays are immensely high-energy radiation, mainly originating outside of the Solar System. They may produce showers of secondary particles, mainly called “secondary muons”, which penetrate and impact the Earth’s atmosphere and sometimes reach the surface. These cosmic rays originate from the supernovae of massive stars. The moun is an elementary particle similar to the electron, but with greater mass. Data of cosmic rays on the atmosphere is collected from different points of the earth at the same time. A program is made through Java to collect automatically the data from those different radars. A mathematical model is developed in order to explain the amount of cosmic rays affecting the population in the Earth’s surface. The results from the modelling are kept in the same program, so they can be used in future researches.

Lopez-Oquendo, Andy

Franco, Eframir - Physics, UPRH

Physics

Protonosphere behavior techniques using indirect measurements of the ionized atmosphere over the Caribbean

The purpose of this research is to develop a methodology for obtaining information Protonosphere based on continuous and indirect measures of techniques based on land and satellites. For this study an index ,IP, based on continuous measurements of the Total Electron Content ,TEC, and electron density at the peak of the ionosphere ,NmF2, was created using GPS receivers and digisonde, respectively. The main goal of this research is to see the behavior of the Protonosphere at different times of the year and also the changes in geomagnetic and solar activity. To achieve this, data from the IP, the Geomagnetic Index ,Kp, Activity and satellite Soho ,solar activity, was collected simultaneously from the June 4, 2004 until December 26, 2011. The data were divided by seasons ,solstices and equinoxes, and for every season the linear relationship between IP and Kp/Soho index was obtained by linear regression, assuming that the relationship between the variables is linear. The regression coefficients obtained were analyzed for each season.

Mendez-Santacruz, Laura L.

310

Escobar, Samuel - Department of Physics, University of Puerto Rico - Rio Piedras, San Juan PR 00936, USA.; Mendoza, Frank - Institute of Functional Nanomaterials, University of Puerto Rico - Rio Piedras, San Juan 00931, USA.; Weiner, Brad - Institute of Functional Nanomaterials, University of Puerto Rico - Rio Piedras, San Juan 00931, USA.; Morell, Gerardo - Institute of Functional Nanomaterials, University of Puerto Rico - Rio Piedras, San Juan 00931, USA.

Physics

Photoconversion of NOx Species by SnO2/Graphene/Graphene Oxide Composite for Water Treatment Applications

SnO2 nanoparticles anchored on graphene oxide (flakes) (SnO2-GO) were fabricated by electrodeposition using the rotating disk electrode technique. The composite was characterized by X-ray diffraction (XRD), Raman Spectroscopy, Fourier transform spectroscopy (FT-IR) and Scanning Electron Microscopy (SEM). The samples show an interesting photocatalytic behavior under ultraviolet irradiation. SnO2-GO has fast and high photosensitivity response in comparison with SnO2 nanoparticles alone. The presence of graphene contributes as an electron transporter of photogenerated charge carriers from tin dioxide nanoparticles. Methylene blue photo-degradation in the presence of the SnO2 catalyst confirmed the effectiveness of this composite as photocatalyst. We exploited this property for the photoconversion of toxic NOx species in water into other environmentally friendly compounds.

Mendoza-Aponte, Lizyan

Muller Rafael - Physics, UPR Humacao; Cersocimo Juan - Physics, UPR Humacao; Vergara Nelson - Physics, UPR Humacao; Martinez Luis - Physics, UPR Humacao; Lopez Andy - Physics, UPR Humacao

Physics

Calculate the separation and position of the binary stars chosen from Washington Stars Catalog

311

In this research that begins in the collection of data from Flagstaff, Arizona. Where NURO observatory is located. The 31-inch telescope contains a CCD camera. This facilitates the work to get the data. The data were working at the observatory of the University of Puerto Rico at Humacao. The data are work processes calibrate and pixalizar. To start the calculation of separation. Pythagorean Theorem is used. The angles are calculated positions with conveyors. Later is passed to the averaging process and offset. To find the average of each star and data in general.

Mercado-Hernandez, Gerardo J.

Physics

Theoretical model of a charged particle interacting with an electric dipole potential

The basic problem we propose to study is the interaction between a charged particle q and the electric field E created by an electric dipole net charge is zero. This situation would find many applications within various scientific disciplines, which involve the interaction of charged atomic and sub-atomic particles. Such as Particle Physics, Chemistry, Atmospheric Physics, etc. The research involve shall be divided in two phases, the first shall comprise using a more intuitive classical physics approach. The second phase shall comprise of using the most important concepts of the classical model to construct a quantum model of the behavior of the interaction.

312

Ortiz-Ortiz, Deliris Nairy

Muller, Rafael - Physics, UPRH; Cersosimo, Juan - Physics, UPRH; Lopez, Andy J. - Physics, UPRH; Vergara, Nelson E. - Physics, UPRH; Martinez, Luis - Physics, UPRH

Physics

Binary Stars systems: Measurement of Angle and Separation

We use the 31 inch NURO telescope with an installed NASACAM CCD camera located in Flagstaff, Arizona at an altitude of 2,117m to acquire the images of the binary star systems. These images are transferred to the observatory of the University of Puerto Rico at Humacao where it is prepared for further analysis. The analysis include the process of calibration and pixalization of the CCD images. After being calibrated and pixalized, the angle is measured using mathematical methods with north facing the right side of the image and the separation of the binary system. Once these analysis are finished, these are published in the Washington Double Star catalog.

Ramos-Ayala, Coral

Velázquez, Rafael - Physics, UPR- Rio Piedras; Cordero, Zuania - Biology, UPR- Rio Piedras; Avalos, Bárbara - Biology, UPR- Rio Piedras; Villalobos, Juan - Biology, UPR- Bayamon; Ferrer, Andrea - Biology, UPR- Rio Piedras; Figueroa, Patricia - Biology, UPR- Bayamon

Physics

Wireless Bacteria Sensor Based on Carbon Materials

Hospital and health communities need a more effective electronic bio-interface to better reduce or eliminate bacterial threat. The biosensor industry fabricates solid devices that are not suitable for biological surfaces such as buccal gums, skin or any other humid surface. The biological surfaces mentioned above are irregular, for that reason the sensor must possess the ability to attach conformably to such

313

surfaces. In order to solve this problem, we propose a flexible resonance wireless sensor that will detect bacteria and their population density. The bio-sensor consists of a printed radiofrequency wireless sensor made of gold, to which graphene, micro and nanocrystalline diamond will be incorporated. This part of the sensor will be attached into a silk water-soluble based substrate; this device will neither work with any batteries nor use wire to transfer the information from the bio-sensor to another device. The silk water-soluble based substrate will allow the bio-transfer of the sensors onto the biomaterials in a simple and efficient manner. Preliminary results have shown that when exposing the nano and microcrystalline diamond to bacteria a change in resistivity of the material is observed, this will produce changes in the radiofrequency response. This innovative platform to build nanosensors for biomedical applications will improve bioelectronics for interface monitoring.

Reyes-Mendez, Marjory

Muller, Rafael - Physics, UPRH; Cersosimo, Juan - Physics, UPRH; Lopez, Andy J. - Physics, UPRH; Vergara, Nelson E. - Physics, UPRH; Martinez, Luis - Physics, UPRH

Physics

Positioning and measurement of binary stars' separation

We select binary stars' systems from the Wasington Double Star catalog and report the position angle measurement and separation of binary stars. We gather the data at the 31 inch NURO telescope, located 20 miles east from Flagstaff, Arizona. The NASACAM CCD camera, with 27 micron pixels and a field of view of 16 arc minutes is attached to the telescope for our measurements. We follow the standard procedure to calibrate the images using bias and flats. The images pixelized to measure the separation of the binary star system and also measure the position angle of the star system. Our data is published at the Washington Double Star catalog. This research project is part of an ongoing gathering of data that has been active for various years.

Rios-Crespo, Maried

314

Rios, Maried - Biology, University of Puerto Rico, Rio Piedras, San Juan, Puerto Rico, U. S. A.; Espada, Ernesto - Biology, University of Puerto Rico, Rio Piedras, San Juan, Puerto Rico, U. S. A.; Limbu, Tej B. - Institute for Functional Nanomaterials, San Juan, Puerto Rico, U. S. A. Physics, University of Puerto Rico, Rio Piedras, San Jua; Mendoza, Frank - Institute for Functional Nanomaterials, San Juan, Puerto Rico, U. S. A.; Weiner, Brad R. - Institute for Functional Nanomaterials, San Juan, Puerto Rico, U. S. A. Chemistry, University of Puerto Rico, Rio Piedras, San J; Morell, Gerardo - Institute for Functional Nanomaterials, San Juan, Puerto Rico, U. S. A. Physics, University of Puerto Rico, Rio Piedras, San Ju

Physics

Electron Microscopic and Raman Spectroscopic Study of Graphene Synthesized by HFCVD

Synthesis of Large area and high quality graphene is a big challenge to the material scientists at present. The most effective technique to obtain such a graphene is the chemical vapor deposition (CVD). Although a number of pioneering works to synthesize high quality and large area graphene is going on currently by using thermal CVD, we have approached a technically different type of CVD namely hot filament chemical vapor deposition (HFCVD) as it is potentially suitable for industrial scale production of the graphene. However, the growth mechanism of graphene in this type of CVD is yet to be discovered. Here, in this work, we have studied monolayer ,bilayer and multilayer graphene synthesized by HFCVD on copper by using scanning electron microscopy (SEM) and Raman spectroscopy in order to understand the growth mechanism. The changes in the graphene islands on copper with the changes in the experimental growth parameters and its correlation with the Raman spectra have been explained. We found that graphene islands increase in area gradually as we increase the deposition time and finally coalesce to each other to form a single sheet. Furthermore, we found that with higher concentration of methane feed gas in the chamber, graphene covers the whole substrate faster but it turns into the multilayer graphene with smaller grain sizes. These results have been explained based on the SEM images and Raman spectra of the as grown and transferred graphene.

Torres-Maldonado, Brian

315

Muller, Rafael - Physics, UPRH; Cersosimo, Juan C. - Physics, UPRH; Lopez, Andy J. - Physics, UPRH; Vergara, Nelson E. - Physics, UPRH; Martinez, Luis - Physics, UPRH

Physics

Measurement of Separation and Position Angle of Binary Stars

We report on separation and position angle measurements of binary stars systems, selected from the Washington Double Star catalog. The data is gathered at the 31 inch NURO telescope, located 20 miles east of Flagstaff, Arizona. The NASACAM CCD camera, with 27 micron pixels and a field of view of 16 arc minutes is attached to the telescope for our measurements. We follow the standard procedure to calibrate the images using bias and flats. The images pixelized to measure the separation of the binary star system and also measure the position angle of the star system. Our data is published at the Washington Double Star catalog. This research project is part of an ongoing gathering of data that has been active for various years.

Vargas-Velez, Kevin

Figueroa, Jose - Physics Department, University of Puerto Rico-Mayaguez; Smith, Robert - Physics Department, New College of Florida ; Lysenko, Sergiy - Physics Department, University of Puerto Rico-Mayaguez

Physics

Nonlinear Optical Properties of Vanadium Dioxide

This work is focused on the investigation of optical nonlinearity of vanadium dioxide (VO2) thin films by optical Z-Scan technique. Thin VO2 films of different thicknesses and morphologies were grown by pulsed laser deposition technique. This material undergoes first-order insulator-to-metal phase transition under ultrafast or continuous wave (CW) laser excitation. The light-induced phase transition in VO2 was studied in order to understand the phase transition dynamics by monitoring the laser power-dependent material response. Also, the influence of internal stresses in VO2 was studied for epitaxial films grown on different crystalline substrates. Z-scan setup was built and aligned to be used with 532nm CW and

316

picosecond pulsed lasers. Two subsequent spatial filters were installed to produce pure Gaussian beam profile which is critical for high experimental accuracy. The measurements of thermally induced phase transition produced by CW laser demonstrate large thermo-optical response of VO2. Using the picosecond laser pulses, we show how the Z-Scan technique provides sensitive and accurate measurement of third-order susceptibility ?(3), and other nonlinear optical constants. Several Matlab programs were made: for image processing to extract the beam profile, and for calculation of nonlinear optical constants. Experimental results show that VO2 exhibits very large negative nonlinear index of refraction. The light-induced monoclinic-to-tetragonal change of VO2 lattice symmetry alters the first-order optical susceptibility ?(1). As a result, Z-scan measurements show atypical Z-scan signal profile. Thus, along with ordinary nonlinear material response due to ?(3) , the signal is noticeably affected by light-induced transformation of ?(1).

Vergara-Figueroa, Nelson

Muller, Rafael - Physics, UPRH; Cersosimo, Juan - Physics, UPRH; Lopez, Andy J. - Physics, UPRH

Physics

Finding pulsar through pre-set detection

Pulsars are neutron stars that have strong magnetic fields. They’re important because tell us more about the nature of stars and the astronomer uses pulsars to study the universe. Since they are important, we hope to find signals with the characteristics of a pulsar. In a collaborative effort between the Arecibo Observatory in Puerto Ric and the University of Texas at Brownsville, we use pulsar candidate data from various radio telescopes. The radio telescope of Arecibo is a reflector with a diameter of 1000ft which makes it the largest dish in the world and it operates at 430 MHz. We are going to present what is a pulsar, how they are formed and how we detect them. To access the data that the radio telescope receives we use web page arcc.phys.utb.edu/viewer and here we classified the possible pulsar.

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Poster Session

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Chemistry

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Acevedo-Esteves, Raul

Morales, Camila - Department of Chemistry, University of Puerto Rico, Rio Piedras; Ortiz, Edwin - Department of Chemistry, University of Puerto Rico, Rio Piedras; Perez, Astrid - Department of Chemistry, University of Puerto Rico, Rio Piedras; Morales, Roberto - Department of Nutrition, University of Puerto Rico, Rio Piedras; Perez, Ivan - Department of Chemistry, University of Puerto Rico, Rio Piedras ; Cabrera, Carlos - Department of Chemistry, University of Puerto Rico, Rio Piedras

Chemistry

ELECTROOXIDATION OF AMMONIA UNDER THE INFLUENCE OF MICROGRAVITY IN PARABOLIC FLIGTHS

The electrooxidation of ammonia have wide potential for its use in space and on earth as an energy producing reaction in fuel cells and for the safe processing of waste effluents containing urea/ammonia from a system for the recovery of water from urine. Experiments in microgravity were performed in an electrochemical half-cell using platinum micropillars as a working electrodes and in a Direct Ammonia Alkaline Fuel Cell DAAFC. Three platinum electrodes with different surface characteristics 1 flat and 2 micropillar height were used as working electrodes in a half-cell containing ammonia 1M pH 10. A Direct Ammonia Alkaline Fuel Cell with a platinum catalyst was used with a solution of ammonia 1M pH 10 as the fuel on the anode side of the fuel cell and air in the cathode side. The experiments were performed aboard a NASA airplane performing parabolic flights creating a microgravity environment. Chronoamperometric analysis of the electrochemical oxidation of ammonia performed in the ground versus microgravity shows a decrease in performance in microgravity for the flat and the short micropillars 32 µm height; for the high micropillars 62 µm height the performance increased versus the ground experiment. For the DAAFC a transient chronoamperometric analysis was performed during 17 parabolic trajectories across the periods of hypergravity 1.7 g and microgravity 0.02g which occurs in an alternate sequence. The data collected shows that the decrease in performance in the DAAFC is directly correlated to the changes in gravity between hypergravity and microgravity.

Acosta-Santiago, Maxier

Rivera, Jose M.

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Chemistry

Elucidating Binding Interaction of 8-Arylguanosine Derivatives with Toll Like Receptors 7 and 8 by Computational Docking Experiments

Recent discovered toll-like receptors (TLR) have been of great interest due to its inter-species presence and its connection to the innate immune response. TLRs 7-9 compose a family of intracellular receptors responding to pathogen associated molecular patterns, which recognize nucleic acids in addition to a number of synthetic small molecule ligands. While some of those ligands bind to both TLR7/8 (e.g., Resiquimod), a subgroup of guanosine derivatives and guanosine like structures (e.g., Loxoribine, Imiquimod) that make them selective TLR7 binder. Currently we have reported 8-aryl-2’-deoxyguanosine derivatives that self-assemble into stimuli-responsive (e.g. pH and temperature) supramolecular G-quadruplexes, that can further assemble into mesoglobules we term supramolecular hacky sacks (SHS). Preliminary in vivo studies with mice have shown that some SHS are immunostimulatory. We hypothesize that such response results from the activation TLR7 by the 8ArG constituents of the SHS. In order to test this hypothesis, we engaged in computational docking experiments (using Maestro and Glide software) with the crystal structure of TLR8 (due to its high homology to TLR7) with selected 8ArGs using the initial findings to establish potential origins for reported selectivity towards TLR7. We will present the results of those studies, giving special emphasis to comparisons between the binding modes of Resiquimod, Loxoribine and selected 8ArGs. The triggering of these receptors can open doors to treatment autoimmune diseases like lupus erythematous and recognition of viral ssRNA (e.g., HIV). These experiments will help give structural information of TLR7 and possible intrinsic modifications to our 8ArG library for multiple biomedical applications.

Alequin-Torres, Denisse

John A. Soderquist - University of Puerto Rico, Rio Piedras Campus

Chemistry

A New Asymmetric BBD Reagent for The Allylboration of Aldehydes

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Our laboratorys main focus is the development of new chiral asymmetric reagents and catalysts using the 10-R-9-borabicyclo3.3.2decane ring systems. Recent studies in our laboratories have revealed that the robust 10-trimethylsilyl-9-borabicyclo3.3.2decane 10-TMS-9-BBD ring system provides a highly effective stereocontrol element for many asymmetric organoborane conversions. Specifically the B-allyl-10-trimethylsilyl-9-borabicyclo3.3.2decane has proven to be an excellent reagent for the asymmetric allylboration of aldehydes and aldimines. Using this exciting new chemistry we designed a new synthesis of homoaldols in enol form which can be hydrolyzed under controlled conditions to form non-racemic 4-hydroxybutanal HBE, which in turn can be used for the synthesis of functionalized substituted tetrahydrofurans oxolanes from bishomoallylic alcohols. These compounds occur widely in nature as constituents of terrestrial and marine organisms. Some of them exhibit remarkable antibiotic or cytotoxic effects, which encouraged a series of studies of their clinical applications. Starting with the lithiation of allyloxy-t-butyldimethylsilane with sec-butyllithium in THF and allowing the lithiated product to react with B-OMe-10-trimethylsilyl-9-borabicyclo3.3.2decane, we were expecting the addition of this lithiated product to be ? as in previous studies in our laboratory had revealed, but instead, we made a major discovery. The lithiation of the allyloxy-t-butyldimethylsilane appeared to take place without forming any chelation as in the case of allyl methyl ether and allyl methoxyethoxymethyl ether. The lithium intermediate is not cyclic as with the other protecting groups, and so electrophiles attack it alpha to the OTBS position with exclusive allylic 1,3 transposition. This resulted in only one diasteromeric trialkylborane product! These developments and other aspects of this new chemistry will be presented and discussed.

Dennis-Aponte, Christian

Claudia Andrea Ospina Millán - Department of Chemistry, University of Puerto Rico at Cayey Campus

Chemistry

Chemical Analysis of Guaiacum officinale

The objective of this study is to evaluate the cytotoxic and anticancer activity of extracts from Guaiacum officinale. The plant were collected, dried and extracted with a mixture of CH2Cl2-MeOH (1:1). The resulting crude extract was suspended in water and extracted with solvents of different polarities. The extract was preliminary screened using the brine shrimp lethality test. Most of the extract was

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cytotoxic with LC50 values of 200 ?g/ml or less. These extract was further protested against two breast cancer cell lines (MCF-7 and ZR-75-1) inhibiting more than 80% of cell growth. Based in our preliminary results we concluded that this showed anticancer activity and merit a closer investigation in order to isolate the chemical compounds responsible of bioactivity. Supported by Institute of Interdisciplinary Research (IIR) and Dean of Academic Affairs of University of Puerto Rico at Cayey.

Gonzalez-Villegas, Julissa

Colon, Jorge - Chemistry Department, University of Puerto Rico

Chemistry

Cointercalation of doxorubicin and cisplatin into zirconium phosphates layers as drug carrier system for cancer therapy application.

During de past decades scientists are employing their efforts developing anticancer drugs to fight against the disease that take the live of millions of people worldwide every year. Doxorubicin was developed in fifties and acts by insertion in DNA inhibiting the Topoisomerase II avoiding the cell replication. Cisplatin coordinates with two guanines in the DNA, distorting the double helix and activating the apoptosis protein system. These drugs are very effective but also have acute side effects due to the lack of selectivity toward cancer cells. The objective of this research is to unify the anticancer potential of doxorubicin and cisplatin into zirconium phosphate,?-ZrP, nanolayers. ZrP works as the selectivity inducting agent taking advantage of its chemical and thermal stability, and the enhanced permeability and retention effect. X-Ray Powder Diffraction, XRPD,; Infrared Spectroscopy ,IR),; Scanning Electron Microscopy- Energy Dispersive Spectroscopy, SEM-EDS, have been performed to characterize the intercalated product. The cointercalation of doxorubicin and cisplatin in ZrP produces a second order diffraction peak of 10.5 Å which correspond to an interlaminar distance of ~20 Å based on previous results of doxorubicin intercalation. Presence of cisplatin was corroborated by the Pt peaks at energies of 9.48 and 2.048 and by IR.

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Gutierrez-Gutierrez, Keily J.

Keily Jose Gutierrez Gutierrez - Chemistry Department UPRRP

Chemistry

Theoretical study in the complexes formed between ascorbic acid and dimethyl glyoxal

Mixtures between Ascorbic acid and dimethyl glyoxal have been used like a potent anticancer. It is usually believed that the biological activity showed by this mixtures is caused by some kind of complex formed by ascorbic acid and dimethyl glyoxal. This mixture could interact with the DNA of malign cells and help to destroy it. We did some calculations for study how could be the structure and the energetic preferences of these complexes. The calculation suggest us that could have a number of different conformers formed.

Hernández-Lebron, Yaritza

Cabrera, Carlos R. - Department of Chemistry, UPR-RP

Chemistry

Platinum Electrodeposition by Cyclic Voltammetry and Chronoamperometry on Microcrystalline and Polycrystalline Boron Doped Diamond for Ammonia Oxidation

Platinum electrodeposition was done at two different boron-doped diamond (BDD) thin films from sp3 Diamond Technologies (Diamond A) and Element six (Diamond B). The electrodepositions were done by chronoamperometry and cyclic voltammetry. The BDD electrodes were characterized by Raman spectroscopy. The Pt electrodeposited BDD electrodes were compared by SEM and ammonia oxidation. Cyclic voltammetry deposition favors the formation of cubic (Diamond A) and cauliflower structures (Diamond B). On the other hand, chronoamperometry electrodeposition favors dendrite formation structures in both BDD electrodes. Platinum electrodeposited by chronoamperometry favors the formation of platinum (100) facets, which enhances ammonia oxidation. Diamond A showed the highest

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ammonia oxidation peak current densities when compared Diamond B. This is attributed to the morphology, polycrystallinity differences, and boron doping levels of the diamond.

325

Joaquin-Ovalle, Freisa M.

Guihurt, Grace - Chemistry, UPR-Rio Piedras; Griebenow, Kai - Chemistry, UPR-Rio Piedras

Chemistry

Photosynthetic apparatus complexes organization of Photosystem I and Photosystem II in Botryococcus braunii

B. braunii is a green colonial unicellular microalga that can produce up to 86% of its dry weight as hydrocarbon oils, which can potentially be used as a renewable fuel. We are currently working on the isolation and characterization of the main protein complexes of B. braunii, which include photosystem I, photosystem II, and the respective light harvesting complexes. The thylakoid membrane was solubilized with the detergent n-dodecyl-?-D-maltoside, DM, in a range of concentrations from 0.6%-3%. The homogenate obtained was subjected to a 15-35% sucrose gradient, and the observable bands were isolated and subjected to blue native polyacrylamide gel electrophoresis, BN-PAGE, to identify the photosystem complexes, dimers, monomers, and small core subunits. Cell rupture was achieved with a Branson sonifier for 30 min at 100 watts. Next, we solubilized the constituents of the thylakoid membrane into stroma and grana membranes with 1% DM. The results obtained from BN-PAGE allowed us to effectively identify the novel super and mega photosystem complexes of 770 kDa, and their dimers 570 kDa, monomers 459-493 kDa, and small core subunits 10-65 kDa. Some microalgae fall in the category of second-generation biofuels, and are currently hot topics in the biotechnology field since they can be used for renewable biofuel production, hopefully meeting the global demand for transport fuels. Therefore, with this project, we intend to commence a study that could relate the photosynthetic apparatus of phototrophic organisms to a more efficient biofuel production.

Lopez-Cubero, Aleannette

Lopez Cubero, Aleannette - Chemistry Department, University of Puerto Rico, Rio Piedras Campus ; Muñoz, S. J. - SEED II Program, Escuela Secundaria Especializada en Ciencias, Matemáticas y Tecnología (CIMATEC); Tinoco, Arthur D. - Chemistry Department, University of Puerto Rico, Rio Piedras Campus

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Chemistry

Quantifying the Affinity Constant for Ti2Tf Based in a New Model for Ti(IV) Coordination for Anticancer Drug Design

Transferrin is a serum protein that transports Fe(III) in our blood to cells but is also believed to participate in the transport of Ti(IV). Ti(IV) is known to exhibit cytotoxic properties and yet can be very unstable. By studying how transferrin binds Ti(IV), we can get an insight into a binding site favorable for the stable delivery of Ti(IV) into cells. The focus of this work is to determine Ti(IV) coordination by transferrin to develop a new drug design for the creation of a Ti(IV) anticancer drug with low side effects for patients. With this objective, spectroscopic techniques were used to determine the specific interactions between transferrin and Ti(IV) and to quantify the affinity constant for Ti2Tf. The data suggest that Ti(IV) binds to only the two tyrosines of the transferrin metal binding site. The remaining coordination sites are fulfilled by the synergistic anions citrate and carbonate. This is a profoundly different model for metal coordination to transferrin. The affinity constant for Ti2Tf was determined by monitoring the formation of the ligand to metal charge transfer absorbance for Ti(IV) coordination to the protein tyrosine residues. At pH 7.4 and 25 Celsius, the affinity constants were log K C-site = 25.2 and log K N-site = 23.5. This suggests that despite the difference in the coordination model, Ti(IV) has a strong affinity for transferrin. This insight has paved the wave for the design of chemical transferrin mimetics that will serve as excellent ligands for Ti(IV) based anticancer complexes.

Loza-Rosas, Sergio Armando

Alexandra M. Vázquez - Biology department, UPR-RP; Arthur D. Tinoco - Chemistry department, UPR-RP

Chemistry

Synthesis, structural characterization and evaluation of cytotoxic effects of the Ti(IV)-Deferasirox complex in A549 lung cancer cells and MAC5 healthy lung cells

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Serum transferrin is responsible for distributing Fe(III) to cells throughout the body. It has been postulated as the hydrolysis stabilizer of compounds of Ti(IV), which are known to be highly unstable in aqueous solution, by effectively chelating the metal ion and transporting it to cells by means via the same endocytotic route as Fe(III). Although this mechanism suggests a promising new anticancer drug design based on the cellular delivery of cytotoxic Ti(IV), efforts to develop a drug sustained in transferrin does not generate results favoring the improvement of the cytotoxic activity of Ti(IV) on cancer cells. Instead, it is proposed to design compounds of Ti(IV) using mimetic transferrin ligands to facilitate not only the stabilization and deliver of Ti(IV), but also to ensure the reduction of intracellular levels of Fe(III), which is detrimental to cancer cells because of their high requirement for Fe(III). Deferasirox, a molecule designed to reduce excess of Fe(III) levels in pharmacological uses has been proposed as a potential chemical transferrin mimetic ligand. It stabilizes Ti(IV) but because it has a stronger affinity for Fe(III), it would be able to exchange Ti(IV) for capture of Fe(III) intracellularly. This study focuses on the synthesis of Ti(IV)-Deferasirox complexes, the characterization of its active structure in solution using solid and solution state approaches including spectroscopic techniques such as MALDI TOF TOF, 13C-NMR, 1H-NMR, and x-ray crystallography, and evaluation of the cytotoxic activity of the complexes in A549 lung cancer cells and healthy lung cells MAC5.

328

Morales-Guzman, Christian

Carballeira, Néstor M. - Department of Chemistry , UPR Río Piedras Campus

Chemistry

Total synthesis of ?5, 9 brominated fatty acids and analogs for biological activity evaluation

The 6-bromo-5E,9Z-hexadecadienoic acid was isolated from the Okinawan marine sponge Xestospongia sp. and its biological activity has not been well studied. This fatty acid is part of a family of fatty acids containing the 6-bromo-5E,9Z-diene functionality, some of which display cytotoxicity. The ?5,9 fatty acids display inhibition of the human topoisomerase I, cytotoxic activity against mouse Ehrlich carcinoma cells and antibacterial activity against the Gram-positive bacteria Staphylococcus aureus. Aimed at studying the antileishmanial, antibacterial and cytotoxic properties of 6-bromo-5E,9Z-hexadecadienoic acid we designed a stereoselective and novel total synthesis of 6-bromo-5E-hexadecenoic acid that consists of 6 steps. The total synthesis and preliminary results will be presented.

Ortiz-Quiles, Edwin

Ortiz-Quiles, Edwin O. - Department of Chemistry, University of Puerto Rico - Río Piedras; Soler, Jess - Jet Propulsion Laboratory, California Institute of Technology; Gobet, Mallory - Department of Physics, Hunter College of City University of New York; Arturo J. Hernández-Maldonado - Department of Chemical Engineering, University of Puerto Rico - Mayagüez; West, William - Jet Propulsion Laboratory, California Institute of Technology; Cabrera, Carlos - Department of Chemistry, University of Puerto Rico - Río Piedras

Chemistry

Lithium Chloride Molten Flux Approach to Li2MnO3:LiMO2 (M = Mn, Ni, Co) “Composite” Synthesis for Lithium-ion Battery Cathode Applications

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In this work, a scalable method for the fabrication of cathodes based on firing pristine compounds Li2MnO3 and LiMn0.33Ni0.33Co0.33O2 with lithium chloride molten flux is explored. This approach offers flexibility in synthesis temperature since the process does not require precursor decomposition. Moreover, the synthesis technique allows for the study of the development from the pristine compounds to the final product (Li1.2Mn0.53Ni0.13Co0.13O2). This could help to understand if Li2MnO3-LiMO2 material system is a true solid solution or a phase-separated composite. Cathode materials were prepared and characterized by electrochemical charge and discharge studies, electrochemical impedance spectroscopy, and different characterization techniques, including lithium magic angle spinning-nuclear magnetic resonance. Stability studies were conducted to investigate the effects of synthesis duration and temperature on the cathode material. Optimal performance was achieved by firing the pristine compounds for 6 hours at 1000 ºC and for 48 hours at 800 ºC, both in the LiCl molten flux (LCMF), resulting in a powder with a solid solution behavior and specific discharge capacity near 240 mAh g-1.

Prieto-Costas, Luis

Yanira Rodríguez - Chemistry, Universidad de Puerto Rico, Recinto Rio Piedras; José M. Rivera - Chemistry, Universidad de Puerto Rico, Recinto Rio Piedras

Chemistry

Synthesis and self-assembly studies of sugar-containing guanosine derivatives

Smart materials that respond to external stimuli (e.g., temperature, pH or light) are a popular research area in chemistry and biology, specially the ones that respond to sugar because of their biomedical applications. Although glucose-responsive systems are attractive due to their potential uses in carbohydrate sensing and diabetes treatments, most of the reported examples are polymeric in nature. Our group has previously developed non-polymeric thermo- and pH-responsive supramolecular G-quadruplexes (SGQs) composed of 8-aryl-2’-deoxyguanosine (8ArG) as a suitable alternative to complement current polymeric systems. Adding a sugar binding entity such as boronic acids (BAs) capable of binding 1,2-cis diols to 8ArdGs will result in sugar-responsive SGQs after assembly. The longer-term goals of this project are to test the sugar-responsive properties of these BA-functionalized SGQs and understand the sugar binding effect in the supramolecular assembly. In the shorter-term, in order to gain a better understanding of such responsive

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systems, we need to understand the role of the sugar moieties on the self-assembly of 8ArGs. Thus, we will present the synthesis and self-assembly studies of glucose- and mannose-containing 8ArGs. The characterization, self-assembly and responsive studies was achieved using techniques such as 1D/2D NMR, Dynamic Light Scattering (DLS), Differential Scanning Calorimetry (DSC) and UV/Vis spectroscopy. We expect the supramolecules made from these sugar-containing 8ArG derivatives, as well as their eventual BA-containing counterparts, to enable materials suitable for multiple biomedical applications.

Rivera-Sanchez, Maria Del C.

Rodríguez-Benítez, Attabey - UPR-RIO PIEDRAS; Rivera, Jose M. - UPR-RIO PIEDRAS

Chemistry

Hydrophilic 8-aryl-2'-deoxyguanosine derivatives as self-assembled ligands for G-quadruplex DNA recognition

G-quadruplex DNA (QDNA) structures are abundant through our genome. Those at the telomeres and promoter regions are associated with regulation of biological processes and have gained a lot of interest in the development of cancer therapies. Although there are many reported examples of small molecules associated in the stabilization of the QDNA structure, to make QDNAs a viable target for drug discovery, there is a need to develop ligands that bind with high selectivity and affinity. Our approach is based on the use of hydrophilic 8-aryl-2'-deoxyguanosine (8ArG) subunits as the building blocks of supramolecular G-quadruplexes (SGQs) that act as self-assembled ligands (SALs) for the stabilization of QDNA structures. We evaluated the interactions between an 8ArG derivative (1) and a dimeric tetramolecular QDNAs and also evaluated the interactions of 1 with more biomedically relevant unimolecular QDNAs such as those from the human telomeric sequence (hTel) and oncogene promoter regions (c-myc, c-kit2, kras35B1). FRET melting assays (in K+/Na+-containing solutions) show that 1 defferentially stabilize these QDNAs. To understand if the stabilizing effect as an effective ligand is associated to the SGQ species, we synthesize an isomer of 1 that does not self-assemble under the experimental conditions used and tested it by FRET melting assays. These results pave the way towards the development of similar SALs as effective tools for biomedical applications in cancer research.

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Rojas-Perez, Arnulfo

Rojas-Pérez, Arnulfo - Chemistry Deparment, University of Puerto Rico; Fuentes, Mariela - Chemistry Deparment, University of Puerto Rico; Robles, Isis - Chemistry Deparment, University of Puerto Rico; Jena, Umakanta - Bioenergy Laboratory, Desert Research Institute; Das, K.C - College of Engineering, University of Georgia; Díaz-Vázquez, Liz M. - Chemistry Deparment, University of Puerto Rico

Chemistry

Demineralization of Sargassum spp. Macroalgae Biomass: Selective Hydrothermal Liquefaction Process for Bio-oil Production

Brown macroalgae Sargassum spp. are one of the most abundant species of algae in the shores of Puerto Rico. Its availability in large quantity presents a great opportunity for use as a source of renewable energy. However, high ash content of macroalgae affects the conversion processes and the quality of resulting fuel products. This research studied the effect of different demineralization treatments of Sargassum spp. biomass, subsequent hydrothermal liquefaction, HTL, and bio-oil characterization. Demineralization constituted five different treatments: nanopure water, nitric acid, citric acid, sulfuric acid, and acetic acid. Performance of demineralization was evaluated by analyzing both demineralized biomass and HTL products by the following analyses: total carbohydrates, proteins, lipids, ash content, caloric content, metals analysis, Fourier Transform Infrared-Attenuated Total Reflectance Spectroscopy, Energy Dispersive Spectroscopy, Scanning Electron Microscopy, and GCMS analysis. HTL of Sargassum spp. before and after citric acid treatment, was performed in a 1.8 L batch reactor system at 350°C with a holding time of 60 min and high pressures, 5-21 MPa. Demineralization treatment with nitric acid was found the most effective in reducing the ash content of the macroalgae biomass from 27.46% to 0.99% followed by citric acid treatment that could reduce the ash content to 7%. Citric acid did not show significant leaching of organic components such as carbohydrates and proteins, and represented a less toxic and hazardous option for demineralization. HTL of untreated and citric acid treated Sargassum spp. resulted in bio-oil yields of 18.4±0.1 % and 22.2±0.1 %, ash free dry basis, respectively.

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Sanchez-Alvarez, Annelis

Sanchez, Annelis - Chemistry, UPR- Rio Piedras

Chemistry

A Close Look to Substance P

A review on substance P and its uses in drug development. Substance P is a peptide composed of eleven amino acids. SP is find in our brain and spinal cord and has been correlated with pain, and inflammatory processes in our body. This review is intended to give a close sight to novel discoveries and future projection of substance p in medicine and specifically as therapeutic alternative.

Torres-Martinez, Zally

Griebenow, Kai - Quimica, UPR-Rio Piedras

Chemistry

Biochemical composition of the photosynthetic apparatus of Caribbean marine macro algae under different environmental conditions

Marine macro algae are one important primary producer in the oceans, utilizing solar energy to fix carbon dioxide in the Calvin Cycle, producing carbohydrates, and releasing oxygen. However, little is known about the adaptation of macro algae to stress conditions, i.e. environmental pollution. The goal of the research is to study the biochemistry and the environmental consequences of pollution and stress conditions on photosynthetic activity of protein complexes involved. The investigated model green alga is Chaetomorpha vieillardi, found in Puerto Rican waters, was selected because it is fast growing and biomass production. The photosynthetic apparatus was isolated from the chloroplasts by homogenization and centrifugation. The integrity of the isolated chloroplasts is tested by fluorescence and absorption spectroscopy. The protein complexes isolated from C. vieillardi are identified, characterized and quantified through native gel and denaturing gel electrophoresis. The photosystems are characterized by absorbance

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and fluorescence spectroscopy for the functional integrity of its components.The biochemical composition of the model alga is determined. The adaptation process of C. vieillardi remains under study although preliminary data demonstrate that stress conditions, (e.g., elevated temperature) slows algae growing and diminished photosynthesis which is caused by damage to the pigment protein complexes involved.

Tu, Kaixiong

Kaixiong, Tu - Department of Chemistry,UPRRP; Zhongfang, Chen - Department of Chemistry,UPRRP

Chemistry

Lithium Adsorption and Diffusion in SnS2 Bulk, Nanosheet and Nanoribbon: A computational investigation

Lithium Adsorption and Diffusion in SnS2 Bulk, Bilayer, Monolayer and Nanoribbon: A Computational Investigation Kaixiong Tu, Zhongfang Chen* Department of Chemistry, Institute for Functional Nanomaterials, University of Puerto Rico, Rio Piedras Campus, San Juan, PR 00931. * To whom correspondence should be addressed. Email: [email protected] (Z.C.) Density functional theory computations were performed to investigate the adsorption and diffusion of lithium (Li) on SnS2 nanosheets and its derived nanoribbons (NRs) in comparison with SnS2 bulk in T phase. The binding energies and diffusion barriers are comparable in SnS2 bulk and bilayer. Reducing the dimension to SnS2 monolayer significantly lowers the Li diffusion barrier while keeping a considerable binding energy. Due to the presence of dangling bonds in the edge, SnS2NRs have an enhanced Li binding energy and increased Li mobility. Thus, SnS2 monolayer and nanoribbons are promising as anode materials of Li-ion batteries with a high power density and fast charge/discharge rates.

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Education

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Santacuz-Sarmiento, Neida

Santacruz, Neida M - Facultad de Educación, Universidad de Puerto Rico Recinto de Río Piedras; Alvarez, Claudia - Facultad de Educación, Universidad de Puerto Rico Recinto de Río Piedras

Education

Análisis de la intervención de módulos constructivistas que atienden “miconceptions” y lagunas conceptuales en tópicos de Física universitaria.

Los “misconceptions”, se han investigado a partir de los años 70 en muchos países, y se ha evidenciado su importancia en la enseñanza y el aprendizaje de la ciencia. Los investigadores en educación, han coincidido en la apremiante necesidad de transformarlos en conceptos científicamente aceptados. A esta transformación se le denomina Cambio Conceptual. Este trabajo de investigación presenta la implementación y el análisis de la intervención de módulos basados en la teoría constructivista que han sido diseñados y elaborados con el fin de conocer, re-estructurar y evolucionar “misconceptions” y lagunas conceptuales en estudiantes universitarios en el tópico de la Física.

Valle-Diaz, Carlos J.

Valle-Diaz, Carlos J. - Department of Chemistry, University of Puerto Rico Río Piedras, San Juan, PR; Hernandez-Perez, Jose A. - Department of Physics, University of Puerto Rico Río Piedras, San Juan, PR; Bendezu-Portela, Eliana - Central High School Specialized in Visual Arts, San Juan, PR; Torrech-Prieto, Carlos A. - University Gardens High School, San Juan, PR; Davila-Hernandez, Gladys - Department of Education, University of Puerto Rico Río Piedras, San Juan, PR; Diaz-Vazquez, Liz - Department of Chemistry, University of Puerto Rico Río Piedras, San Juan, PR

Education

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Nature and Technology in Parallel: An interdisciplinary module of Science-Technology-Engineering-Art-Mathematics (STEAM) for 8th-12th grade students

As part of the GK-12 fellowship initiative to develop and implement educational materials in the middle and high school curriculum while forming a learning community through which the teacher will learn content knowledge and the graduate student fellow pedagogy, we present here an interdisciplinary module that bridges environmental science and nanoscience. We applied the general definition of an electrical circuit as a starting point to design the activities of our module where the student will discover that the water cycle, a natural circuit, behaves similarly like an electrical circuit. Throughout the activities the students will learn concepts related with the water cycle (environmental science) and an electrical circuit (nanoscience and technology) in order to establish the aforementioned relationship. We expect that the student will manage to associate the parts of an electrical circuit (i.e., voltage source, electrons, cables, resistors, and capacitors) with the components that drives the water cycle (i.e., temperature gradient from surface to air, water molecules, atmosphere, aerosols, and clouds) in order to achieve a greater scope of the innate relationship between nature and technology. Partnering with our fellow teachers that work in specialized schools in arts, mathematics and sciences, our module uniquely represents STEAM related activities for grade school students from 8th to 12th grade. The students will particularly utilize art and mathematics to explain microscopic processes that occur both in nature and technology under the overarching GK-12 concept of System Dynamics. We will present our preliminary results on student experiences in some of our activities.

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Electronics

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Contreras-Ospino, Boris

Contreras, Boris - Electrical and Computer Engineering, UPR-MAYAGUEZ; Flores, Anthony - Electrical and Computer Engineering, UPR-MAYAGUEZ

Electronics

Automated Radiation Hardened gate enclosed MOSFET Model Extraction

Gate enclosed or annular MOSFETs are transistors with inner drain/source and outer source/drain where the drain and source area are asymmetric. Annular MOSFETs are being used in environments which exposure to radiation quickly hinders the performance of standard MOSFETs by constantly reducing their threshold voltage. The accurate prediction of their width over length ratio is not easily predicted. This significantly increases their time to market, which in turn increases the cost. In industry, the creation on an accurate regular MOSFET transistor model in a new technology, may take several months, designers usually simulate each transistor as two large parallel transistors in order to diminish the error in simulation. This project presents the creation of a model for gate enclosed transistors using conformal mapping. It successfully mimics the parameter extraction of an annular MOSFET. It approaches a rectangular model using equipotential lines for its mapping. The parameter extraction is accomplished using standard testing for a reduced BSIM3 model while still providing accuracy. Typical models include approximately one hundred twenty six parameters, however recent developments show that only twenty-two parameters are needed to accurately simulate circuits transfer curves. This project shows the simulation and a comparison to experimental results. The automation of the parameter extraction is accomplished developing a GUI that controls the instrumentation and collects statistical data to form a model from the extracted parameters. The process is repeatable for other technologies thus fast tracking the model creation part for new technologies.

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Engineering

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Delgado-Castro, Miguel

Delgado, Miguel - Mechanical Engineering, Universidad del Turabo; Romero, Edwar - Mechanical Engineering, Universidad del Turabo; Rodriguez, Hector - Mechanical Engineering, Universidad del Turabo

Engineering

Failures in Machinery and its Vibrations: Reproducing failures.

This work aims to inform about the different failures that occurs in rotating machinery and the methods used to reproduce them in a Machinery Fault Simulator. In rotating machineries, the vibrations play an important role in the failure detection. If some fault has certain behavior that differs from the other damage and if this occurs for every type of failure in the system, then it could be possible to determine which fault is occurring in the system just by analyzing its vibrations. This project will explain the failures that could be reproduced in the simulator as: Shaft Misalignment, Unbalance, Sheave or Pulley Misalignment and Bearing Defects. It will also show the techniques used to analyze the vibrations as the Phase Measuring, Eccentricity and Resonance Frequency. It is expected to learn about the Rotating machinery faults along with the way of simulating these failures for their experimental analysis.

Díaz-Lozada, Gelson

Engineering

Energy Generation Using Mechanical Force Simulator for Knee Implant

Energy can be harvested from almost anywhere, either through moving objects, heat generators, biological waste, etc. Researches has been conducting energy harvesting studies from natural resources seeking for clean energy. Human body can be considered as an energy source since the human body is in constant motion. This paper will emphasize in energy generation for knee implants using

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piezoelectric ceramics and the human knee movement for the purpose of monitoring and prevention of implants wear. Also, the implementation of a mechanism simulating the force exerted in the knee during walking activities will be emphasized.

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Bernier-Casillas, Yomarie

Pérez-Jiménez, José R. - Biology, Universidad del Turabo


Isolation and Characterization of Hexadecane-Degrading Bacteria in the Martín Peña Canal in Puerto Rico

Alkanes reach the environment by anthropogenic activities and natural processes. Bacterial contribution to alkane degradation has been documented for polluted and temperate sites. The objective of this research is to isolate and characterize putative hexadecane-degrading bacteria across the Martin Pena Canal. Soil samples, collected in the Martin Pena Canal, were cultivated, as consortium, on rich media to obtain the native microbiota. The community was described using 16S rDNA-TRFLP profiles, which result in a high diversity among study samples. Alkane-degrading bacteria-ADB were isolated by aerobic cultivation on mineral media supplemented with specific alkane as sole carbon source and subjected to 16S rDNA sequencing. Isolates have been evaluated for polyhydroxyalkanoates-PHA production and resilience test, such as temperature, 5% NaCl, osmotic pressure, EPS production, among others that are advantageous for plant development to promote rhizoremediation. Seven ADB, mostly Klebsiella strains, were isolated in hexane but were also able to degrade isooctane and hexadecane. Preliminary results have demonstrated several strains capable of producing PHA, important in the production of bioplastics and rhizosphere survival. To seek a better understanding of the Canal and the degradation of hexadecane at a molecular level, soil samples were taken from nine points along the 3.5 miles. Bacterial communities of these samples were described using 16S rDNA-TRFLP profiles. Preliminary results have shown distinct communities for certain regions. ADB prevails across Neotropical ecosystems, despite pollution level, are phylogenetically diverse, and harbors novel genetic variants. These alkane-degrading bacteria provide novel isolates to deal with pollution and disclose processes in nature.

Erazo-Oliveras, Angelica

Erazo - Oliveras, Angélica - Department of Environmental Sciences, UPRRP; Rios - Dávila, Rafael A. - Department of Environmental Sciences, UPRRP

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Metagenomic monitoring of the microbial communities of a slow sand filter

There are approximately 239 small community water systems in Puerto Rico, which serve 2% of the population, known as Non - PRASA. The majority of these systems do not provide adequate water treatment, which results in a lack of compliance with relevant regulations. Slow sand filtration provides a suitable treatment alternative that might be used by these systems. In spite of its known efficiency, this treatment has its limitations mostly related to a lack of knowledge of the processes that occur in the biological layer, which is responsible for the majority of the contaminant removal. New molecular techniques, such as metagenomics, now allow for the study of these complex microbial systems. Understanding of the interactions within the biofilm will result in a better utilization of slow sand filters in Non-PRASA communities, thus resulting in improved public health and compliance with relevant regulations.

Feliciano-Lopez, Kariana

Hernandez Miranda, Yalexa M.


Stomata Adaptation to heavy metal Stress in Arabidopsis thaliana

Stomata are structures in the leaves of plants that regulate the exchange of gases with the atmosphere, thus playing an important role in the ecosystem. It has been shown that the mechanism for opening and closing of stomata is regulated by physical and chemical processes, as well as hormones. Currently, many stomata genes involved in the regulation of biological processes are already known, for example, previous work has shown the presence of contractile proteins (actin and myosin). In this work, the aim is to verify the expression of certain genes that are present in the stomata and observe the effect of cadmium in the plant Arabidopsis thaliana. Plants were exposed to different concentrations of the metal and by enzymatic hydrolysis and with micromanipulation the stomata were isolated. The RNA was extracted and was subsequently converted into cDNA. Using stomatal cDNA of exposed and unexposed plants, PCR and RT-qPCR was performed to

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verify the genetic expression. The results show that the genes SAND Family and Metallothionein 2B, SCAB1 and NCED3 are present in the stomata; however, using regular PCR, no difference was shown between the plants exposed and not exposed to cadmium. In conclusion, although this work demonstrates that the genes under study are present in the stomata, an accurate quantification of the gene expression is required.

Fortune-Alerte, Jodany

FORTUNE Jodany - UPR-Rio Piedras; GERVAIS Gary - UPR-Rio Piedras


Micronutrient Demand and Balance in a Bench Scale Anaerobic Digester Producing Biogas from Marine Macroalgae.

Biogas production from anaerobic digestion of marine macroalgae is an area of active research interest for fuel production. Our research focus is the microbial conversion of marine macroalgae into biogas in a bioreactor operating in seawater. The anaerobic digestion of biomass for methane production is a well-established technology, although the use of sea water is innovative. The successful development of a macroalgae-based biofuel industry will require a careful nutrient balance and recovery system in order to be technically and economically viable. We have confirmed that by using an appropriate design strategy, methanogenesis can occur, even in full strength seawater and despite the reported inhibition due to sodium and sulfur. Furthermore, we hypothesize that our macroalgae feedstock (Sargassum spp.) contains all micro nutrients necessary to maintain a healthy microbial population. ICP- OES is used to determine the concentration of 10 critically important micronutrients (Ni, Co, Mo, Zn, Cu, Fe, Cu, Mn, Ca, Mg). Our study is to confirm the hypothesis that Sargassum spp. provides complete nutrition for the maintenance of the microbial population.

Hogan-n/a, James Aaron

Hogan, J. Aaron - University of Puerto Rico-Rio Piedras Campus, Rio Piedras, PR, USA; Jess K. Zimmerman - University of Puerto Rico-Rio Piedras Campus, Rio

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Piedras, PR, USA; Aaron B. Shiels - 2USDA, National Wildlife Research Center-Hawaii Field Station, Hilo, Hawaii, USA; Nicholas V. Brokaw - University of Puerto Rico-Rio Piedras Campus, Rio Piedras, PR, USA


Responses of trees over a nine year period to an experimentally-induced hurricane in the Luquillo Experimental Forest, Puerto Rico

Two key factors of landscape-scale hurricane disturbance, canopy openness and detritus deposition, were imposed on the tropical wet forest of the Luquillo Mountains, Puerto Rico. In a 2 x 2 factorial replicated design replicated in three blocks, canopy openness was increased by trimming tree canopies, and we manipulated debris by adding and subtracting the trimmed materials. Over the nine-year study period, beginning in 2003, tree recruitment, mortality, growth and diversity data was collected for all stems ? 1 cm dbh. Trimming of the canopy resulted in an approximate doubling of the stem densities and recruitment rates increased greater than 25-fold. The deposition of debris did not notably influence stem densities or dynamics, but did have small yet significant positive effect on tree basal area. Significant decreases in stem densities in treatments with intact canopies are attributed to on-going forest thinning observed throughout the area as forest succession and canopy closure dominate the dynamics following the compounded effect of the two most-recent severe hurricane disturbances in 1989 and 1998, respectively. This situation enabled an experimental test of the responses to experimental canopy thinning and detritus deposition in the context of predictions of the Intermediate Disturbance Hypothesis (IDH). There was a poor fit to IDH predictions, especially when diversity measures were corrected for differences in stem density among plots. These results are similar to recent studies of mainland tropical forests, indicating that IDH is a poor explanation for the high diversity of tropical forests, whether in island or mainland locations.

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La Quay-Velazquez, Giomara

José C. Verle Rodrigues - Estación Experimental Agrícola, UPR-Mayaguez


Gall formation on the endemic cactus, Leptocereus quadricostatus, induced by the invasive mealybug, Hypogeococcus pungens (Hemiptera: Pseudococcidae)

The introduction of Harrisia cactus mealybug (HCM), Hypogeococcus pungens, in Puerto Rico causes concern due to its permanent effects to the structure of cacti communities, eliminating susceptible species. HCM is a polyphagous gall-inducing scaly insect considered an aggressive pest outside of its native range of South America. So far, in Puerto Rico, three species of cacti have been observed to be infested with this invasive HCM, the natives Pilosocereus royenii, Melocactus intortus, and the endangered endemic Leptocereus quadricostatus. Recent studies have shown that HCM affects the growth and survival of P. royenii, but little is known about the other affected species. To understand more about the threat of HCM to L. quadricostatus, greenhouse experiments were designed to describe the formation of galls and evaluate the pest population dynamics. The experimental design consisted of two groups of L. quadricostatus plants, infested and non-infested, the infested treatment received 20 crawlers and six females per plant of HCM obtained from natural occurring populations in Cabo Rojo. The first signs of successful infestation were observed after 27 days of the initial pest transference, while the first signs of gall formations were observed after 97 days. The initial stage of the pest population growth fits an exponential model. To our knowledge this is the first time that the full infestation process, including gall formation, by HCM has been replicated under controlled conditions. These results provide a better understanding of the interaction between HCM and the endangered host plant, and aims to develop more effective management strategies.

Morales-Medina, William R.

Rios-Hernández, Luis

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Comparison of the Liquid and Solid Fraction of Photosynthetic Biomass as Separated Feedstock for Biogas Production Through Anaerobic Digestion

The production of an alternative energy source to substitute fossil fuels is a world necessity as the natural oil reservoirs continue to be depleted. A viable alternative is methane; this natural hydrocarbon is the main end-product of microbial populations responsible to recycle the organic matter in anaerobic environments where carbon dioxide is the dominant electron acceptor. This biogas has a calorific value which is only surpassed by hydrogen; it is self-purified, and could be combusted in concentrations as low as 30%. These characteristics make methane one of the top alternative energy sources of the future. In this preliminary work we used non-edible photosynthetic biomasses from marine and terrestrial origins as feedstock in anaerobic reactors to produce biogas. To do this, we homogenized the biomass in a blender and the liquid was separated from the solids by centrifugation. Both fractions were used separately as feedstock to feed a batch reactor (160 ml serum bottle) inoculated with a methanogenic microbial community previously selected for its ability to degrade different biomasses. Methane production was quantified weekly by Gas Chromatography and was used as an indicator of microbial activity. Our data shows that the majority of the methane in our reactors was produced from the solid fraction and not from the liquid fraction of the biomass regardless of the origin, marine or terrestrial. Interestingly, bioreactors fed with untreated biomass produced similar quantities of methane suggesting that the homogenization of the biomass does not increase the production of methane.

Nina-Espinosa, Jorge L.

Lugo Vega, Johnny - Environmental Sciences Dept., UPR, Rio Piedras ; Nina Espinosa, Jorge L. - Environmental Health Dept., UPR- Medical Sciences Campus


Biomass Ethanol Production for Flex Fuel Vehicles: The BBFuels of Puerto Rico Business Project,

BBFuels of Puerto Rico, LLC: A Sustainable Industrial Model for Bioethanol Production in Puerto Rico BBFuels de Puerto Rico, LLC is a green company that

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proposes a novel approach to biomass conversion to energy that reduces the overall process complexity required to produce ethanol by means of wet water hyacinth of Puerto Rico (Eichhornia crassipes). The problem that this project solves are the lack of E85 supply for FFV owners and the overpopulation of hyacinths. Due to hyacinths high lignocelluloses content they can be considered a promising substrate for the production of bioethanol. For that reason, the development of ethanol from water hyacinth of Puerto Rico is the innovation offered by this proposal. Water Hyacinth has an extremely rapid growth rate that that clogs rivers and prevents navigation due to a perfect environment: the tropics. It could be useful as a source of biomass because of its abundance and feasible cultivation. The impact that this innovation could have over society consist of improving the quality of life and the environment while providing an alternative fuel that is less pollutant at a lower cost than fossil fuels. This innovation would provide E85 ethanol for flex fuel vehicles being acquired despite the lack of E85 in the Puerto Rican market. Key words: water hyacinth, ethanol E85, FFV.

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Olivero-Lora, Sofia

Olivero Lora, Sofia - Environmental Science Department, College of Natural Science, University of Puerto Rico-Río Piedras Campus; Meléndez-Ackerman, Elvia - Environmental Science Department, College of Natural Science, University of Puerto Rico-Río Piedras Campus


Ecosystem services by urban green infrastructure in residential yards in a tropical city: Integrating information on social drivers, green infrastructure management and ecosystem assessment tools.

The resilience of urban areas, were more than half of the world population lives (UNFPA, 2007), dependents on the ability of the urban space to maintain simultaneously certain human and ecological functions (Alberti et al. 2003). A key component is residential green infrastructure, which provides opportunities for the provision of localized key ecosystem services because humans have direct (and indirect) impact on socio-ecological characteristics on these areas through management decisions. On the other hand, the management discourse advocates the use of native trees as sustainable landscaping/urban forestry practices (McKinney 2002), but the differences in ecosystem services by native or non-native vegetation have been rarely quantified. Because of this, in order to improve strategies for green infrastructure management, both social and ecological drivers need to be considered. This study addressed ecosystem services production by residential yards as green infrastructure within the Rio Piedras Watershed in conjunction with the San Juan ULTRA-Ex collaborative project. We address questions related to perception and attitudes toward urban residential native and non-native vegetation, how these social drivers are associated to the actual management of green spaces, and the use of an ecosystem assessment tool (Forest Service’s i-Tree Software, Nowak & Crane 2000) to evaluate the provision of ecosystem services in residential yards. This study uses a social-ecological approach by focusing on ecosystem system services considered important by urban residents of the San Juan Metropolitan area and evaluating how these ecosystem services are distributed across different socio-economic groups in the city.

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Sharma, Shweta

Sharma, Shweta - Environmental science, UPRRP; Saxena, Manoj - Environmental science, UPRRP; Tinoco, Arthur - Chemistry, UPRRP


STUDY OF STABILITY OF HUMAN SERUM TRANSFERRIN FOR MAINTAINING THE EQUILIBRIUM OF TITANIUM IN THE BLOOD

Titanium(Ti) concentration in the blood increases by implant degradation in peri-implant environment. Ti species shows toxicity at higher concentration like 50 ?g/ml. Transferrin(Tf) and citrate act as complexing molecule to keep Ti in soluble form and helps in maintaining equilibrium of Ti in the blood. Tf is a family of bilobal iron-binding proteins that have two metal binding sites at its cleft formed by subdomain. Transferrin is only 30% iron saturated so it can bind with other metal and can be used as metallodrug. Crystal structure of apo Tf and holo Tf have provided insight about fully opened and closed conformation respectively of Tf-protein. When appropriate metal ion and synergistic anion binds at Tf metal binding site it makes its lobe properly closed. This type of metal-Tf complexes are more stable than apo Tf. In experimental study going on in our lab, we are seeking to understand whether Ti bound to Tf in holo form or mixed Fe-Tf-Ti form are more stable. This structure will provide insight for Ti coordination to ligands at metal binding site and also physiological role of synergistic anion such as citrate. The study of structural stability, coordination and physiological role of citrate can provide insight into the possible mechanism of Ti-Tf equilibrium mechanism inside the blood.

Sharma-Kumar, Rohit Kumar

Saxena,Manoj - Department of Environmental Sciences, University of Puerto Rico, R?o Piedras Campus; Ramirez- Paz,Josell - Department of Chemistry, University of Puerto Rico, R?o Piedras Campus; Griebenow,Kai - Department of Chemistry, University of Puerto Rico, R?o Piedras Campus


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Development and application of renewable lipase nanoparticles for sustainable production of biodiesel and to transform glycerol into pharmaceutical precursors

The world is still largely relying on nonrenewable energy production for its ever growing energy needs with its severe negative impacts on the environment and resulting in resource depletion. Biodiesel has emerged as one potential alternative fuel from renewable sources. However, the source of raw material to produce biodiesel is an extremely important factor to consider in order to not compete with food related production and to optimize yield and minimize cost. Due to easy availability and high lipid content, algae based raw materials have emerged as a promising choice, but rapid and efficient conversion of algal lipids to biodiesel still remains a challenge. Furthermore, conventional biodiesel production employs toxic chemicals during the production process (KOH or NaOH). We therefore aimed at also creating a renewable catalytic method for the transesterification reaction and employ lipases. Lastly, the result of biodiesel production is a glycerol glut and we are working on transforming glycerol in precursors of pharmaceuticals and other fine chemicals. Specifically, we are working on modification of lipases from a variety of sources for catalytic enhancement and stabilization in biodiesel production. Our aim is to develop efficient, stable and reusable lipase nanoparticles, which efficiently convert algal lipids to biodiesel in reactor type settings. We have already obtained promising lipase nanoparticles (NP) using Rhizopus arrhizus lipase. Around 25-fold activity enhancement was observed by using nanoparticles in non-aqueous conditions. Fine-tuning of other parameters, such as, pH, temperature, and salt concentration during NP formation are also under optimization to attain maximum activity and stability.

Torres-Delgado, Elvis

Torres Delgado, Elvis - Department of Environmental Science, University of Puerto Rico; Valle Diaz, Carlos J. - Department of Chemistry, University of Puerto Rico; Baumgardner, Darrel - Droplet Measurement Technologies, Colorado; McDowell, William H. - Department of Natural Resources and the Environment, University of New Hampshire; González, Grizelle - International Institute of Tropical Forestry, US Forest Service; Mayol-Bracero, Olga L. - Department of Environmental Science, University of Puerto Rico


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Impact of African dust on cloud and rain chemistry and cloud microphysics in a Caribbean cloud forest

To improve our understanding of the role of long-range transported African dust (LRTAD) in cloud formation processes in a tropical montane cloud forest (TMCF) in the Caribbean region we had field campaigns measuring dust physical and chemical properties in summer 2013, as part of the Puerto Rico African Dust and Cloud Study (PRADACS), and in summer 2014, as a part of the Luquillo Critical Zone Observatory (LCZO) and in collaboration with the Saharan Aerosol Long-Range Transport and Aerosol-Cloud-Interaction Experiment (SALTRACE). Measurements were performed at the TMCF of Pico del Este (PE, 1051 masl) and at the nature reserve of Cabezas de San Juan (CSJ, 60 masl). In both stations we monitored meteorological parameters (e.g., temperature, wind speed, wind direction). At CSJ, we measured light absorption and scattering at three wavelengths (467, 528 and 652 nm). At PE we collected cloud and rainwater and monitored cloud microphysical properties (e.g., liquid water content, droplet size distribution, droplet number concentration, effective diameter and median volume diameter). Preliminary results for summer 2013 showed that in the presence of LRTAD the average conductivity of cloud water was almost twice (81.1 uS/cm) as that in the absence of LRTAD (47.7 uS/cm), the average conductivity in rainwater was slightly higher (15.0 uS/cm vs 12.8 uS/cm), and the average pH was slightly higher for both cloud and rainwater samples (average of 6.41 for cloud water and 6.37 for rainwater).Results from both sampling campaigns will be presented at the meeting.

Venero-Venero, Ingrid

Mayol - Bracero, Olga L. - Department of Environmental Sciences, University of Puerto Rico - Rio Piedras Campus; Rivera - Collazo, Isabel. - Department of Sociology and Anthropology, University of Puerto Rico, San Juan, Puerto Rico ; Perez, Carlos. - Institute of Puerto Rican Culture, San Juan, Puerto Rico.


Assessment of the suitability of a coastal archaeological site as a record of past atmospheric particle presence in sediments

This project aims to determine if sediments from a coastal archaeological site can be used as a proxy registry to identify the presence of atmospheric particles in the

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past. The quality of the sedimentary record in evidencing past atmospheric conditions will be assessed by determining site formation processes and using three air quality indicators (mineral dust, volcanic ash and black carbon) in the coastal archaeological site of playa Jayuya that belongs to the Late Holocene period (300 – 700BC) located in the premises of the Cabezas de San Juan natural reserve in Fajardo, Puerto Rico. This pre-Columbian site contains materials and artefacts associated with the Saladoid native culture that introduced pottery, canoe craftsmanship and horticulture to the native Indians (the arcaicos) living in the island. Therefore, with this study, we intend to enhance Puerto Rican cultural knowledge and provide paleoenvironmental data from the site since as its in danger of disappearing due to the erosive forces of waves and sea level rise. Sediment core samples will also be obtained in the coastal lagoon “Laguna de Aguas Prietas” to compare results from both depositional environments.

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Geosciences

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Rivero-Vega, Rafael

Geosciences

STRATIGRAPHY, SEDIMENTOLOGY, AND AGE OF THE MORRISON FORMATION: INVESTIGATION OF A ROAD-CUT IN NORTHWESTERN LAPORTE, COLORADO

Along a section of road cut in Northwestern Laporte, Colorado, the some colored mud and siltstone is clearly visible. Geologists in the area agree that it is the Morrison Formation but there has been no work undertaken previously to ascertain its lithologic composition and geologic age. This study aims to generally describe the stratigraphy, sedimentology, and depositional environment of the location and correlate with other outcrops in the vicinity to place the section within a geologic time period. The unit is approximately 21 m thick and composed of mostly dark green-grey siltstones and red-brown/cream-orange mudstones with some moderately developed paleosol outcrops. The paleosols contains clay nodules, carbonate sediments, clay-and calcite-filled rhizocretions, and a mottled and “popcorn weathered” pattern (the latter signifying smectitic clays). The depositional environment is interpreted as a mud- and silt-dominated floodplain of a fluvial system with seasonal shifts in moisture content. The lithology resembles other sections in the Colorado area which date to the Upper Jurassic, Late Kimmeridgian time.

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Life Sciences

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Alejandro-Alejandro, Michel

Patricia Burrowes - Biology, University of Puerto Rico Rio Piedras; Karla Vazquez - Biology, University of Puerto Rico Rio Piedras

Life Sciences

Can amphibian body temperatures predict their vulnerability to a pathogenic chytrid fungus in different environments?

Studies focusing on the interaction between amphibians and a deadly chytrid fungus, Batrachochytrium dendrobatids Bd, have suggested the importance of ambient temperature in determining host vulnerability and the pathogen’s infective success. This is expected since amphibians are ectothermic and Bd has an optimal temperature growth curve between 17 and 25 C. However, little is known about how specific environmental-dependent temperature regimes can affect host’s capacity to evade this pathogen, or make it more vulnerable to disease. In this study, we contribute to a global effort to determine this interaction for different amphibian species and environments across the world. Our model is Eleutherodactylus coqui who is susceptible to this pathogen and is declining in high mountain forests of Puerto Rico. We used agar models casted for E. coqui to monitor frog’s body temperature Tb and water loss in two microhabitats sun/dry, sun/wet within three different ecosystems El Yunque, Carite and the University of Puerto Rico Rio Piedras campus from August to November of 2014. We used HOBO Pro v2 data loggers to measure both Tb and and corresponding microhabitat temperature Te in 24-hr periods, and accounted for skin evaporative-water loss by weighing frogs every 4 hours with pesola scales. Results show that frog Tb varies significantly with location and microhabitat choice; and point out that warmer and wetter forests represent potential refugia from Bd for vulnerable species that could physiologically adapt to such environmental conditions.

Burgos-Rodriguez, Jhoset A.

Aviles-Rodriguez, Kevin - Biological Sciences, University of Rhode Island; Karraker, Nancy - Natural Resources, University of Rhode Island; Kolbe, Jason J - Biological Sciences, University of Rhode Island

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Life Sciences

Effects of Introduced Green Iguanas (Iguana iguana) on Seed Germination and Dispersal in a Tropical Plant Community in Puerto Rico

Despite the importance of dispersal and germination for plant life cycles and population dynamics, the effects of reptiles are often overlooked because herbivory is relatively rare in reptiles. Green Iguanas Iguana iguana enhance seed germination in some plant species in xeric habitats in its native range, but no studies have been conducted on introduced populations, such as in Puerto Rico. Because Green Iguanas can be abundant where they have been introduced, they have the potential to affect plant communities by dispersing and germinating seeds. In summer 2013, a total of 258 Green Iguana scat samples were collected in the Humacao Natural Reserve in southeastern Puerto Rico. To determine the percentage of seeds that germinated and the number of days to germination, seeds were extracted from scat and collected from fruit, and then planted under common garden conditions using four experimental treatments. Four main species were identified from seeds in wild Green Iguana scat: native Anona glabra, Ficus sp., non-native Peltophorum pterocarpum, and Pterocarpus sp. To assess seed dispersal potential by Green Iguanas, we collected GPS coordinates for scat samples and surrounding mature trees. Green Iguana consumption of A. glabra fruits may be a direct threat to native Puerto Rican slider turtles Trachemys stejnegeri stejnegeri, which consume these fruit as an important component of their diet. Green Iguanas do not have consistent effects on seed germination and dispersal among different plant species in introduced habitats, but multiple physiological and ecological characteristics suggest that they may be important seed dispersers.

Casillas-Pagan, Karla

Carlos Rullan Lind - Department of Biochemistry, UPR Medical Sciences campus ; Dr. Abel Baerga Ortiz - Department of Biochemistry, UPR Medical Sciences campus

Life Sciences

Expression, purification, and characterization of PfaR: a putative regulator of polyunsaturated fatty acid biosynthesis

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Polyunstaurated fatty acids (PUFAs) are important components of human health and nutrition that have been associated with numerous health benefits. With the diminishing availability of natural PUFAs due to overfishing, it will be important to identify novel sources of these important compounds. One of these important sources is deep-sea bacteria, which are capable of making PUFAs efficiently and anaerobically using a polyketide synthase (PKS) enzyme complex. Directly upstream of the PKS genes is a putative regulator called pfaR, which encodes a 36kD putative transcription factor which is conserved in some species of Shewanella genus, all known producers of PUFAs. Due to the location of pfaR in the PUFA synthase gene cluster, we hypothesize that this gene is involved in the transcriptional regulation of Eicosapentaenoic Acid (EPA) biosynthesis. The goal of our study is to clone the pfaR gene into a suitable vector, to express and purify the protein, and ultimately to assess the ability of PfaR to increase the yield of PUFAs in bacterial fermentations. So far, we have cloned the pfaR gene into pET-200/TOPO plasmid vector and expressed it in E. coli BL21 cells; where protein expression was induced with isopropyl-b-D-thiogalactopyranoside (IPTG). A strong, visible band in the 36kD region, present after induction with IPTG, proves the successful expression of PfaR. The protein was purified using nickel affinity columns, and a buffer containing imidazole was used to elute the protein. Efforts are underway to further characterize PfaR and its role in PUFA biosynthesis.

De Jesus-Villanueva, Christina

Velez-Zuazo, Ximena - University of Puerto Rico Rio Piedras; Falcón, Wilfredo - Institute of Evolutionary Biology and Environmental Studies, University of Zurich; Stephen, Catherine - Utah Valley University; Rivera, Cristina - University of Puerto Rico Rio Piedras; Papa, Riccardo - University of Puerto Rico Rio Piedras

Life Sciences

Genetic Population Structure of the Invasive Green Iguana (Iguana iguana) in Puerto Rico

Green Iguanas (Iguana iguana) have become an established and widespread invasive in Puerto Rico. Due to economic loss in agriculture and degradation of road infrastructure, they have been categorized as an invasive nuisance by the local Department of Natural Resources and the Environment. Although their presence is conspicuous throughout the island, little is known about their genetic population structure. In this study, we will determine the level of genetic diversity of I. iguana across the island. To do so, we will sample 20 individuals from two

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populations and from five regions across the island. To test for population structure, we will investigate how genetic diversity is partitioned among and between Puerto Rican populations of I. iguana using genetics and microsatellite makers. We expect to successfully determine the level of genetic diversity and provide information for effective management practices

Delgado-Suazo, Peter

Pablo Cantero - Biology Department, University of Puerto Rico, Rio Piedras Campus; Michel Alejandro - Biology Department, University of Puerto Rico, Rio Piedras Campus; Rafael Joglar - Biology Department, University of Puerto Rico, Rio Piedras Campus

Life Sciences

Distribution and current status of Mountain Coqui (Eleutherodactylus portoricensis)

The distribution of Eleutherodactylus portoricensis has been informed in the past all across the Central Mountain Range and Luquillo Mountain Range of Puerto Rico at elevations surpassing 180m. According to some reports, the populations belonging to this species have been declining in the last decades. The aim of this work is to study the distribution and current status of E. portoricensis. We visited a total of 83 study sites across the Central Mountain Range and Luquillo Mountain Range in order to determine the distribution of this species. Fieldwork was done between 2013 and 2015 for a total of 180 man-hours. The results obtained show that Eleutherodactylus portoricensis was only found in seven study sites; these were limited to El Yunque National Forest in the Luquillo Mountain Range and Carite State Forest in the Eastern part of the Central Mountain Range. Several factors, such as the destruction of habitat and climate change, have affected negatively the populations belonging to E. portoricensis. The presence of the chytrid fungus Batrachochytrium dendrobatidis has also been suggested to contributing to the population decline of E. portoricensis. This species does not have any protection from the federal government. We recommend that E. portoricensis be included in the lists of endangered species as the first of a series of measures to mitigate the damage that affects its populations.

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Duque-Osorno, Maria F.

Hernandez, Marimar - Department of Biochemistry, University of Puerto Rico-School of Medicine; Noble, Gabriel - Department of Biology, University of Puerto Rico-Rio PIedras Campus; Raimundi, Antonio - Department of Biology, University of Puerto Rico-Rio PIedras Campus; Rivera, Stephanie - Department of Biology, University of Puerto Rico-Rio PIedras Campus; Gonzalez, CArlos I. - Department of Biology, University of Puerto Rico-Rio PIedras Campus

Life Sciences

The effect of p38 MAPK on HuR on stimulated Jurkat T cells

IL-3 is a pro-inflammatory cytokine secreted by T cells that promotes stimulation and differentiation of myeloid cells. Previous results from our laboratory demonstrated that IL-3 expression is regulated by the Adenine/Uridine-Rich Elements (AREs) present in the 3’-untranslated region (3’-UTR). The ability of AREs to modulate gene expression is dependent on ARE-Binding Proteins (ARE-BPs) that specifically recognize these regulatory sequences. Interleukin-3 (IL-3) AREs are recognized by Human antigen R (HuR) which is known for its role in mRNA stabilization and translation. HuR is a nuclear protein that shuttles to the cytoplasm to perform its stabilizing role after being phosphorylated. The ARE-mediated post-transcriptional regulation is regulated by the p38-MAPK signaling during inflammatory or stress stimulus. In order to assess the possible role of p38 in the HuR regulation upon T cell stimulation, Jurkat T cells were stimulated with phorbol-12-myristate-3-acetate(PMA) and ionomycin (IO) in the presence of the p38 selective inhibitor SB202190. Subsequently, the HuR dynamics on activated T-cells were observed by immunofluorescence. In addition, changes in HuR subcellular localization were further confirmed by Western Blot analysis from cytoplasmic and nuclear extract after 6, 12 and 24hrs of T cell activation. 2D gel analysis results showed that the inhibition of the p38 MAPK induces a change in HuR phosphorylation pattern. In addition, the immunofluorescence and Western Blot results also showed that p38 inhibition affects HuR subcellular localization upon T cell stimulation. Collectively, these results suggest a role of p38 MAPK pathway in the regulation of HuR on activated T cells.

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Habiba-Mohamed, Khaled

Axel Arroyo Tarraza - Department of Chemistry, University of Puerto Rico -Rio Piedras Campus, San Juan, PR, USA; Joel Encarnación Rosado - Department of Biology, University of Puerto Rico -Rio Piedras Campus, San Juan, PR, USA; Jose A. Gonzalez-Feliciano - Department of Biology, University of Puerto Rico -Rio Piedras Campus, San Juan, PR, USA; Carlos I. Gonzalez - Department of Biology, University of Puerto Rico -Rio Piedras Campus, San Juan, PR, USA; Javier Avalos - Department of Physics, University of Puerto Rico -Bayamon Campus, Bayamon, PR, USA; Gerardo Morell - Department of Physics, University of Puerto Rico -Rio Piedras Campus, San Juan, PR, USA

Life Sciences

Graphene Quantum dots in Cancer Theranostics

Functionalized graphene quantum dots were synthesized by the bottom-up approach through the irradiation of a liquid hydrocarbon precursor using a pulsed laser. The functionalization of these nanoparticles with polyethylene glycol provides higher solubility and enhancement in their fluorescence quantum yield in aqueous solution. Graphene quantum dots were characterized by UV–Vis spectroscopy, transmission electron microscopy, Raman spectroscopy, X-ray photoelectron spectroscopy, PL emission spectroscopy, and Fourier transform IR spectroscopy. We have tested their toxicity in different human cell lines, and they did not affect the cell viability at concentrations up to 500 µg/ml. Moreover, graphene quantum dots were employed as high contrast nanoprobes in confocal and fluorescent microscopy, which make them suitable in imaging. In addition to their use in diagnosis, we tested them in therapeutic strategies such as photodynamic therapy and drug delivery. We found that they generate reactive oxygen species when irradiated at specific excitation wavelength. Taking together their photoactivity and their ability to deliver some insoluble drugs to tumors, make them promising in cancer therapy.

Hernandez-Matias, Liz

Dr. Mellado, Hunter - Internal Medicine, Universidad Central del Caribe in Bayamon.; Dr. Washington, Anthony V. - Biology, University of Puerto Rico; Ramirez, Julyanas - Biology, Universidad de Puerto Rico

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Life Sciences

JAK2 mutation in patients with Essential Thrombosythemia

Essential thrombocythemia (ET) is a myeloproliferative disorder. This acquired malignant hematopoietic disease is often associated with clinical thrombosis as a complication, and a mutation that constitutively activates JAK2 kinase (JAK JAK2V617F). JAK2 mutation is present around the 57% of ET patients. ET patients present with an increase in platelets and a dysfunction in neutrophils that is accompanied by an increase in cytokine levels. This increase in cytokines is correlated with neutrophil count, but not with platelets count. Activated neutrophils can affect the hemostatic system in a number of ways and can increase the risk of thrombotic events. Thus, our investigation will be focused on the roll of neutrophils in ET. In more detail, we want to know if the dysfunction of neutrophils is responsible for the increase of cytokines, if the neutrophil dysfunction is associated with the risk of thrombotic events and if there is a difference depending in the JAK2 status of the patient. We will evaluate a cohort of 26 patients with ET in which we plan to conduct these studies.

Lopez-Cruz, Luis

Luis Manuel Lopez Cruz - Department of Biology, University of Puerto Rico, Río Piedras Campus, San Juan, PR, 00931; T. Malinich - Department of Biology, Central Michigan University, Mt. Pleasant, MI, 48859; K. Pangle - Department of Biology, Central Michigan University, Mt. Pleasant, MI, 48859, CMU Biological Station, Institute for Great Lakes R

Life Sciences

Spatial Patterns in the Abundance of the Spiny Water Flea (Bythotrephes longimanus) in Northern Lake Michigan

Bythotrephes longimanus is a large predatory cladoceran that was introduced in the Great Lakes in the 1980s and has since had a large impact on the native zooplankton community. The spatial distribution of Bythotrephes in the Great Lakes is thought to be control by fish predation, resulting in greater densities in near vs. offshore regions; however, evidence of these spatial patterns is almost entirely limited to southern Lake Michigan. To test the generality of these patterns, we

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measured the abundance of Bythotrephes at paired nearshore (<15m depth) and offshore (>50m depth) sties around Beaver Island in Northern Lake Michigan during the summer of 2012. Supporting previous research, we found that Bythotrephes density was generally greater at the offshore sites than at the nearshore sites, and this difference grew larger as the summer progressed. Interestingly, these differences were apparent even when sites were only separated by 1.5 km, demonstrating the potential for rapid changes in densities in space. Our findings indicate the substantial spatial variability in the impact of Bythotrephes in large lakes and indicate the importance of Bythotrephes to the diet of nearshore fish, given the high level of predation required to maintain these spatial patterns.

366

Lopez-Lopez, Edgardo

Lopez, Edgardo - Biology, University of Puerto Rico Rio Piedras; Massey, Steven - Biology, University of Puerto Rico Rio Piedras

Life Sciences

Testing the relationship between body size, effective population size and DNA repair

The most essential molecules of all living organism, that store the genetic information is DNA. The stability and integrity of this molecule can suffer damage thanks to the environment or errors in replication during cell division, leading to possible mutations and even disease. To counteract these possible situations, species have evolved mechanisms to repair DNA and try to maintain the purity that distinguishes us as different species. It is predicted that the DNA repair capacity-DRC in large bodied animals is higher, and this should correlate to the number of DNA repair genes present. This research is focus to test the body size hypothesis of DNA repair and tumor suppressor genes using genome sequences of different mammals. To maintain a QC environment we will perform an analysis of false positives produced by assembly errors using read depth analysis, those allows the analysis of recently diverged ORFs, and also understand positive correlation between body size and longevity, which has been linked to an increased efficiency in DNA repair. Multiple sequentially Markovian coalescent-MSMC method will be implemented to calculated link effective population size-Ne with body size and also levels in genome heterozygosity to get a direct method to measure the strength of selection to analyze protein coding genes and the relative frequency and predicted effects of nonsynonymous SNPs. The aim of this project is to test the predicted link between body size and DRC and establish an inverse relationship between body size and Ne using mammalian genomes in silico analysis.

Martinez-Vargas, Marina

Gonzalez, Jose A. - Biology, UPR-Rio Piedras; Gonzalez, Carlos I. - Biology, UPR-Rio Piedras

367

Life Sciences

The Role of Adenine/Uridine-Rich Element-Binding Proteins in the post-transcriptional regulation of Human Interleukin-3 mRNA in T cells

Human Interleukin-3 (hIL-3) is a cytokine that promotes myelopoiesis, differentiation of macrophages and granulocytes. Aberrant expression of this lymphokine has been associated with several hematological cancers. IL-3 3’-UTR harbors Adenine/Uridine-Rich Elements (AREs) involved in its post-transcriptional regulation. ARE-Binding Proteins (ARE-BPs) play key roles in the recognition and function of these sequences. Previous results from our laboratory identified ~18 proteins between 12 to 82kD interacting with the hIL-3 ARE in Jurkat T cells using RNA affinity purification, MS/MS and Western Blot approaches. The goal of this study is to characterize the role of these recently identify ARE-BPs in the post-transcriptional regulation of hIL-3. To achieve this goal, knockdown analysis against HuR and KHSRP ARE-BPs are currently being performed. We expect this data to support a better understanding of HuR and KSRP effects in the hIL-3 post-transcriptional regulation. Ultimately, elucidating the role of these ARE-BPs in IL-3 expression can provide new insights about ARE-mediated post-transcriptional control and blood cancer.

Morales-Cruz, Moraima

Cruz, Alejandra - Department of Chemistry, UPR-Rio Piedras; Figueroa, Cindy - Department of Chemistry, UPR-Rio Piedras; Gonzalez-Robles, Tania - Department of Chemistry, UPR-Rio Piedras; Muñoz, Laura - Department of Chemistry, UPR-Rio Piedras; Molina, Anna - Department of Chemistry, UPR-Rio Piedras; Griebenow, Kai - Department of Chemistry, UPR-Rio Piedras

Life Sciences

Targeted Delivery of Cytochrome c-based Nanoparticles Coated with a Poly(lactic-co-glycolic acid)-Poly(ethylene glycol)-Folate Conjugate to HeLa Cells

The inactivation of the upstream components of the signaling pathways (e.g. p53 pathway) that activate the release of Cytochrome c (Cyt c) from the mitochondria to the cytoplasm avoid the apoptosis mechanism in many cancer cells. To overcome

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this, we aim at delivering Cyt c to the cytoplasm of cancer cells. Recently, we demonstrated that Cyt c nanoparticles were able to induce programmed cell death in an in vitro cell culture study. These nanoparticles consisted of a Cyt c core stabilized by a cover consisting of PLGA, a FDA approved polymer. Herein we extend this study by transforming the system into an active delivery system. The ligand chosen, FA, was linked to poly(ethylene glycol) (FA-PEG) and that to PLGA in order to target folate over-expressing cells. The construct should also avoid RES uptake and facilitate cellular uptake. In comparison to the initial system, the improved one shows enhanced stimulus release properties and higher cell cytotoxicity. The FA-PEG-PLGA-Cyt c NPs was able to reduce the cell viability to 20% whereas the same complex without FA (i.e. PEG-PLGA-Cyt c NPs) only reduced it to 80% in HeLa cells, which is a folate-positive cell line. Confocal microscopy shows that the FA-PEG-PLGA-Cyt c NPs was internalized preferentially by HeLa cells and that the bioconjugate was capable of endosomal escape. The results clearly demonstrate that the new complex is able to improve the Cyt c stabilization upon formulation of a smart drug delivery system and to increase the tumor specificity of the Cyt c-based NPs.

369

Ortiz-Gomez, Valerie

Russo Wiscovitch R. - Biology, UPRRP; Rivera-Perez J. - Biology, UPRRP; Cano R. - Biology, California Polytechnic State University; Toranzos G.A. - Biology, UPRRP

Life Sciences

Paleoparasites, detection their presence in ancient human feces

DNA sequencing of pre-Columbian coprolites has provided information on the fecal microbiota and parasite burden of ancient humans. Ten pre-Columbian coprolites were utilized to detect intestinal parasites in co-existing cultures; the Huecoid and Saladoid from the Island of Vieques, Puerto Rico. Using metagenomic and bioinformatics techniques, the cores of ten coprolites were used for DNA isolation and then sequencing of the 18S rRNA. Bioinformatics revealed sequences of important enteric protozoan parasites such as: Giardia spp., Cryptosporidium spp., Entamoeba spp., and Eimeria spp. Nematodes detected: Schistosoma spp., Necator spp., Taenia spp., Ancylostoma spp. and Ascaris spp. Interestingly, the sequences found included some of the parasite vectors such as Anopheles spp., Aedes spp., Biomphalaria spp., and Physa spp. Most of the other enteric parasites are known to be transmitted by the fecal-oral route, the presence of the vectors may be the result of the consumption of the host species (such as Biomphalaria), although the presence of Aedes spp. sequences cannot be explained the same way. These pathogens usually cause enteritis, an affliction incompatible with the formation of coprolites. The protozoans were more diverse and abundant than the nematodes. The parasitic burden was heavier in the Saladoid than in the Huecoid. Multiple infections were apparent, leading to suspect poor overall health. The finding of coprolites indicated clearly that there were no symptoms associated with gastroenteritis. This may be a result of coevolution allowing host resistance to diseases brought about by enteric parasites.

Perez-Hernandez, Yamilette

Colon Luis.G - UPR-Rio Piedras; Díaz Jessica - UPR-Rio Piedras; Fernández Monica - UPR-Mayaguez ; Washington Anthony.V - UPR-Rio Piedras

370

Life Sciences

Modulation of platelet functions due to TLT1-Moesin interaction.

Activation of platelets is a key element in coagulation as well as in the inflammation response. Activation consists of a series of signals leading to the expression of molecules not normally found on the platelet surface. Amongst these molecules we find the Triggering Receptor Expressed in Myeloid cells (TREM)-like-transcript (TLT)-1. Current evidence suggests that it is a significant player in the inflammatory response and platelet aggregation. TLT-1’s mechanism of action, however, remains unidentified. Here we strive to decipher the mechanism of TLT-’s role in platelet activation. We previously demonstrated that TLT-1 interacts with moesin, a cytoplasmic scaffolding protein. Little is known about this interaction, representing a gap in our knowledge. To better understand TLT-1 function, a first step would be to decipher which regions are important to mediate TLT-1 interaction. We have limited the moesin interaction down to the last 35 amino acids of TLT-1. Evaluating the phosphorylation sites of TLT-1 we identified to date 12 serine and threonine possible phosphorylation sites using a TLT-1 monoclonal antibody and mass spectrometry. We are presently mutating some of the serines in distal end of the cytoplasmic tail to see if any are important for interaction with moesin. We hypothesize that mutation of one of the three serines or the one threonine in this region predicted to be phosphorylated by mass spec may disrupt this interaction. This poster will present the current state of our project.

Ramirez-Paz, Josell

Saxena, Manoj - Sharma, Rohit K.; Griebenow, Kai

Life Sciences

Site-specific glycosylation of L-asparaginase II: effects on structure, activity and stability

L-Asparaginase II is a tumor inhibitory enzyme considered a cornerstone in the treatment of acute lymphoblastic leukemia. Leukemia cells are incapable to synthetize L-asparagine endogenously, forcing them to rely on external sources for its rapid propagation. L-Asparaginase II acts by catalyzing the hydrolysis of asparagine to aspartic acid and ammonia, depleting its concentration from circulating pools, to subsequently induce apoptosis. But despite its former application (since 1970s), protein instability still represents a huge limitation. One

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strategy to enhance stability is through glycosylation, the covalent attachment of sugar polymers (glycans) to proteins. This approach has been extensively studied by us with promising results, but in a random fashion through natural lysine residues. Now we extent this concept to site-specific glycosylation, by attaching glycans through recombinantly introduced cysteine residues in selected positions of the protein. This approach allow us to specifically correlate the effects of glycosylation on L-asparaginase II structure, activity and stability. So far we accomplished to clone and express L-asparaginase II with a yield of 30 mg/L of culture and purity ?95% by SDS-PAGE. Our recombinant enzyme exhibited the same hydrodynamic size, activity and structure than the natural L-asparaginase II. We identified susceptible proteolytic and immunogenic epitopes in the protein’s surface through an in situ model, and performed the corresponding mutations that will serve as glycosylation points at selected positions. Now we will proceed to characterize and glycosylate our mutants, to subsequently correlate its effects on L-asparaginase II structure, activity and stability.

372

Rivera-Colon, Angel

Ruiz, Mayte - University of Puerto Rico, Rio Piedras; Monteiro, Antónia - National University of Singapore; Papa, Riccardo - University of Puerto Rico, Rio Piedras

Life Sciences

Genomic architecture of eyespot number variation in the butterfly Bicyclus anynana

Butterfly wing patterns provide excellent examples for integrative research at the interface of the genetics and development of phenotypic diversity, as they present complexity in the genetics underlying the formation of a wide variety of phenotypic traits. In the butterfly Bicyclus anynana, the wing pattern consists of marginal eyespots in the ventral and dorsal sides of fore and hind wings of both males and females. In B. anynana, studies have identified specific genes involved in eyespot development, but the genetic architecture underlying eyespot number variation is unknown. Thus, the objective of this study is to characterize the genetic basis of eyespot variation using a wide genome approach and a combination of qualitative and quantitative measures, to determine genotype variation among individuals that exhibit different dorsal hindwing eyespots number phenotypes. This will allow us to characterize the genetic architecture behind it and how it differs between the different phenotype groups. In a broader view, our study will allow to comprehend the impact that natural and sexual selection have over existing traits and how they affect and lead to the development of novel characteristics in organisms, particularly in the context of the recruitment of old sets of genes into new functions, as seen in butterfly wing patterns.

Rivera-Rodriguez, Emmanuel

Quiñones, Hector - Biology, University of Puerto Rico, Rio Piedras; Méndez, Hernán G. - Biology, University of Puerto Rico, Cayey; Báez, Marcel - Biology, University of Puerto Rico, Rio Piedras; Jiménez, Carlos A. - Fisiología, University of Puerto Rico, Recinto de Ciencias Médicas; Agosto, José L. - Biology, University of Puerto Rico, Rio Piedras; Giray, Tugrul - Biology, University of Puerto Rico, Rio Piedras

373

Life Sciences

Ih Current blocker ZD7288 feeding to honey bees causes changes in learning and memory

Ih currents are mixed cation currents produced by Hyperpolarization-activated cyclic nucleotide channels (HCN). Ih currents are associated with the regulation of electrical activity in neurons, with effects including related to epilepsy and dopaminergic signaling. Honey bees represent a model where Ih current and behavior could be studied after pharmacological manipulations, since the honey bee HCN channel has been characterized for current kinetics, hyperpolarization activation, cyclic nucleotide regulation, and shown to be similar to the mammalian HCN channel. Biogenic amines like Dopamine (DA) (or Octopamine; OA) are known to modulate learning in insects. In order to study the effect of changes in Ih currents in the honey bee (Apis mellifera, sp.), we used ZD7288, an Ih blocker. We observed that indeed Ih blocker application is associated with changes in learning and memory of the honey bee. Using a place preference avoidance-conditioning assay, we found that changes in Ih causes significant changes in learning acquisition and does negatively influence short-term memory in honey bees. Using the proboscis extension assay, we found that Ih does not affect appetitive learning. These results, taken together support the hypothesis that Ih current is important for DA release. Our results on changes in learning, specifically in short-term memory, caused by Ih blocker, suggests an interaction between Ih current and dopaminergic regulation.

374

Mathematics

375

Arrieta-Arrieta, Eddie

Janwa, Heeralal - Matematicas. Uprrp

Mathematics

On the Fully Homomorphic Encryption Scheme of Gentry

More than thirty years after the discovery of the RSA cryptosystem, the problem of devising a fully homomorphic encryption scheme was an open conjecture. Craig Genetry in his Ph.D. Thesis at Stanford has recently accomplished this feat. We present an exposition of this scheme and discuss some applications.

Li-Chen, Yiming

Eric Yiming Li - Department of Physics, UPR-Rio Piedras; Renyuan Yang - Department of Physics, UPR-Rio Piedras; Ali Aldalbahi - Department of Chemistry, KSU; Peter Feng - Department of Physics, UPR-Rio Piedras

Mathematics

Controllable Growth of Nano Diamond Composite for High Performance of UV Photodetector

Nano diamond composite films are deposited on metal substrates by using hot-filament chemical vapor deposition (HFCVD) technique. The average grain size from micrometer, to submicro and to nanometer was controllable by varying CH4 concentration. The scanning electron microscopy (SEM) is used to examine the morphologies of the surfaces of the samples. Raman scattering spectroscopy and XRD data indicate the concentration of the defect in the obtained composite increases with methane concentration, resulting in a rise of the mobility of electrons and holes that minimize the resistance of the composite. However, the orientation of crystalline structure remained nearly unchanged. In this paper, we focus our experimental studies on sensitivity, response time, recovery time, repeatability, and stability of the designed UV photodetectors. Electrical properties of different types

376

of nano diamond composites and temperature effect are also characterized. Experimental data clearly shows that the nano diamond composite based UV photodetecttor has much better sensitivity and quicker response than that of highly crystalline diamond film-based detector. The response time down to 0.6 milliseconds and the fall time to 0.8 milliseconds were achieved.

377

Martinez-Rivera, Juan

Carmen Gonzalez, Ana - Department of Mathematics, University of Puerto Rico Mayaguez -Campus ; Chou, Ching-Shan - Department of Mathematics, Ohio State University

Mathematics

Connection between Mathematics, Computational Science and Biology

What is the connection between Mathematics, Computer Science and Biology that creates many of the modern fields that rely on this base? With the application of Mathematical principles, Physics made the transition from a qualitative to a quantitative science about 3 to 4 centuries ago. Biology is making the transition now. Mathematical biology is today a fast growing, well recognized, albeit not clearly defined subject. In this presentation we take a look at how the collaboration between the fields of Mathematics, Computer Science and Biology have helped create and extend many of the fields and create new ones. We also take a look at various specific examples that showcase this alliance which in term show several of the advancements that have been developed in thanks to the various works and collaborations done in these fields.

Orozco-Garcia, Juan

Janwa, Heeralal - Mathematics, UPR Rio Piedras

Mathematics

On the Parameters of Hermitian Codes

We present results from investigation into the parameters of Hermitian codes and related algebraic geometric codes.

378

Reyes-Carranza, Roberto

JANWA, HEERALAL - MATHEMATICS, UPR- RIO PIEDRAS

Mathematics

Some New Families of Differentially Uniform APN functions

We present some new techniques to construct differentially uniform APN functions. These new techniques are quite different in that the trace function is not involved----as is the case in previous research work. In the process, we have discovered some new families that are not CCZ equivalent to the existing families, and that have highly desirable non-linear properties for applications in cryptosystems.

379

Rivera-Rivera, Edwin

Janwa, Heeralal - Mathematics, UPR Rio Piedras

Mathematics

Investigation into Research Experience for High School Students in Cryptography

During the past several years, we have been teaching High School students to carry out research projects in Cryptography and Coding Theory. We will present our findings.

380

Physics

381

Agarwal-Agarwal, Radhe

Agarwal, Radhe - UPR-RP; Sahoo, Satyaprakash - UPR-RP; Resto, Oscar - UPR-RP; Katiyar, Ram - UPR-RP

Physics

Enhanced Photovoltaic Properties in Graphitic carbon nanospheres (GCNS)-TiO2 Nanocomposite based Dye Sensitized Solar Cell

Dye sensitized solar cells (DSSCs) have engendered great research interest with promising potentials in solar cell technology for their high power conversion efficiencies. In this study, we report a novel carbon based TiO2 nanocomposite electron injection layer towards the improved performance of DSSCs. A unique acidic treatment of multi-wall carbon nanotubes was utilized to synthesize graphitic carbon nanospheres (GCNSs). Structural and morphological properties of as synthesized GCNSs and GCNS- TiO2 composites were investigated using Raman spectroscopy and ultra-high resolution transmission electron microscope (UHRTEM). Raman mapping and electron energy-loss spectroscopy (EELS) mapping were performed to further characterize the GCNS-TiO2 photoanodes.. Photovoltaic performance of DSSC containing GCNS-TiO2 composite photoanodes were studied. A systematic increment in the short circuit current density (JSC) and open circuit voltage (VOC) of DSSC was observed by increasing GCNS concentration up to an optimal value, probably due to the combined effect of slight rise in quasi-Fermi level and higher carrier transport rate in the resultant composite. Thus, a significant enhancement in the overall photovoltaic performance of such DSSCs with GCNS-TiO2 composite photoanode.

Dugu, Sita

Shojan P. Pavunny - Natural Science, University of Puerto-rico, Rio Piedras; Yogesh Sharma - Natural Science, University of Puerto-rico, Rio Piedras; Ram S. Katiyar - Natural Science, University of Puerto-rico, Rio Piedras

382

Physics

Structural and dielectric properties of silicon modified strontium titanate

In spite of excellent qualities of SiO2 as a gate oxide, the tunneling effect through the film emerged when the dielectric thickness reduced to few atomic layers creates major problem for the microelectronic industry. Thus in the last two decades, the silicon based microelectronics industry advanced towards the miniature of gate only by replacing SiO2 with high k-dielectric material. With this motivation, we have synthesized silicon modified strontium titanate high-k dielectric material by high energy solid state reaction method and their properties were investigated for logic and memory device applications. X-ray diffractometry and Raman spectroscopy studies revealed that synthesized perovskite material has a cubic fluorite crystal structure. The dielectric constant and the loss tangent at 100 kHz were measured to be ~450 and ~0.03, respectively at ambient conditions without any significant frequency and electric field dependence. The observed leakage current density was 0.07 nA/cm2 at 2.5 kV/cm which is very low. This material has been identified as a potential high-k candidate for the future complementary metal-oxide-semiconductor, CMOS, logic and memory technology nodes in terms of its electrical properties in the ceramic form.

Escobar-Veras, Samuel

Méndez Santacruz, Laura - Department of Physics, University of Puerto Rico - Rio Piedras, San Juan, PR 00936, USA.; Mendoza, Frank - Institute For Functional Nanomaterials, University of Puerto Rico, San Juan, PR 00931, USA.; Weiner, Brad - Institute For Functional Nanomaterials, University of Puerto Rico, San Juan, PR 00931, USA.; Morell, Gerardo - Institute For Functional Nanomaterials, University of Puerto Rico, San Juan, PR 00931, USA.

Physics

Photoconversion of NOx Species by SnO2/Graphene/Graphene Oxide Composite for Water Treatment Applications

SnO2 nanoparticles anchored on graphene oxide (flakes) (SnO2-GO) were fabricated by electrodeposition using the rotating disk electrode technique. The composite was characterized by X-ray diffraction (XRD), Raman Spectroscopy,

383

Fourier transform spectroscopy (FT-IR) and Scanning Electron Microscopy (SEM). The samples show an interesting photocatalytic behavior under ultraviolet irradiation. SnO2-GO has fast and high photosensitivity response in comparison with SnO2 nanoparticles alone. The presence of graphene contributes as an electron transporter of photogenerated charge carriers from tin dioxide nanoparticles. Methylene blue photo-degradation in the presence of the SnO2 catalyst confirmed the effectiveness of this composite as photocatalyst. We exploited this property for the photoconversion of toxic NOx species in water into other environmentally friendly compounds.

Hernandez-Perez, Jose Alberto

Carpena-Nuñez, Jennifer - Physics, UPR RIO PIEDRAS; Valentín, Luis - Physics, UPR RIO PIEDRAS; Fonseca, Luis - Physics, UPR RIO PIEDRAS

Physics

Transport Properties of Single Indium Tin Oxide Nanowires

High crystalline quality Indium tin oxide (ITO) nanowires were grown via vapor-liquid-solid method at 850 oC, with Sn in the 3 - 5% concentration range. Pristine nanowires were annealed at 1300 oC in air environment for 30 minutes, to determine their thermal tolerance, as a promising transparent conducting oxide (TCO) that can operate in harsh environments. XRD and TEM-SAED suggest a body centered cubic structure with Ia3 ? (206) symmetry group, assuring that good crystalline quality is maintained during annealing. Their electrical and thermal conductivities, and the Seebeck coefficient were measured in each individual nanowire before and after annealing using specialized microdevice at different temperatures between 190K and 370 K. The Seebeck coefficients at room temperature of two samples before and after annealing were 47, 53 ?V/K and 52, 68 ?V/K , respectively. Which confirms the stability of the nanomaterial at high temperatures and makes it a good candidate to develop temperature sensors and thermoelectric energy nanodevices, that can operate at temperatures above 1000 oC. Details will be given in the presentation.

Instan-Ballesteros, Alvaro

384

Pavunny, Shojan - Department of Physics, UPR-RP; Kooriyattil, sudheendran - Department of Physics, UPR-RP; Pradhan, Dhiren - Department of Physics, UPR-RP

Physics

BCZT thin films for electrical energy storage applications

Recently research energy storage and power generation materials has turned towards lead-free and environmentally-friendly dielectric BaTiO3 based ferroelectric materials because of their high dielectric constant, polarization and high piezoelectric properties. High performance electrical energy storage capacitors are critically important for next generation energy storage devices. Barium titanate and its varitions are widely used in electrical applications especially in multilayer capacitor, this is based in its high dielectric constant with low dielectric loss and high dielectric breakdown field are useful in energy storage capacitor applications. (Ba0.85Ca0.15)(Zr0.1Ti0.9) (BCZT) relaxor ferroelectric thin films with different thickness (5, 10, 15, 20 layers) were investigated in metal-insulator-metal (MIM) capacitor configuration under high electric fields to evaluate their energy storage characteristics. Perovskite phase polycrystalline films were fabricated on conducting Pt(111)/TiO2/SiO2/Si substrates by chemical solution deposition technique. Studies in structural phase transition, ferroelectric, dielectric, leakage current, and energy-storage properties revealed the applicability of this material in future high energy density capacitors. We will present the aforementioned properties of these thin films and will discuss the intended energy storage applications of this dielectric material in detail. High energy capacitors are those which can store as much as high energy per unit volume and the accumulated energy in ferroelectrics are determined by the integral area of the P-E loops.

Limbu-Bahadur, Tej

Frank Mendoza - Institute for Functional Nanomaterials, PR; Oscar Resto - Department of Physics, UPR, Rio Piedras; Brad R. Weiner - Department of Chemistry, UPR, Rio Piedras; Gerardo Morell - Department of Physics, UPR, Rio Piedras

Physics

385

Large Area Bilayer Graphene Synthesis by HFCVD for Transparent Conductive Electrodes

We have synthesized large-area and uniform bilayer graphene by hot filament chemical vapor deposition (HFCVD). The graphene films obtained are uniform and with low defect density. Raman spectroscopy mapping for the ratio of 2D to G band intensities shows that over 90% of the area is covered with bilayer graphene. However, symmetric 2D band in the Raman spectrum of the film shows that the graphene is turbostratic in nature. Moore pattern in the high resolution transmission electron microscopy (HRTEM) images confirm that the graphene is bilayer. Fast Fourier transform (FFT) of the HRTEM images further confirm that the two graphene layers are rotated with respect to each other by 30 degree. Sheet resistance of the graphene is about 5 K?/sqr and transparency is over 93%. In order to reduce the sheet resistance of the graphene, we doped the graphene with an electron acceptor molecule tetracyanoethylene (TCNE). We found that the sheet resistance of the graphene is reduced significantly due to the molecular doping without the considerable loss in transparency. Employing the layer by layer transfer process and doping with suitable concentration of TCNE molecules, we obtained the optimized values for sheet resistance and transparency of the graphene sheets. The study shows that the molecular doping with TCNE can result in the production of the effective transparent conductive electrodes to replace the commercially available transparent electrodes such as indium tin oxide (ITO) and Fluorine doped tin oxide (FTO).

Luis-Matos, Angela

Hernandez, Jose - Fisica; Ruiz, Angel - Fisica; Fonseca, Luis - Fisica

Physics

Magnetic and Electrical Characterizacion of Iron Manganese Silicide Nanowire (Fe1-xMnxSi NWs)

Iron Manganese Silicide nanowires (Fe1-xMnxSi NWs) is a ferromagnetic semiconductor which is believed to be a promising building block for Si-based spintronic devices with fascinating magnetic properties. Transition-metal silicides are widely used as contacts and interconnect in current microelectronics and they are promising for fundamental studies and potential applications in electronic devices, optoelectronics, thermoelectric, and spintronics. Silicide nanowires (NWs)

386

in particular may find application as low-resistance interconnects, or as nanoelectrodes for attaching small electrically active structures. In this Poster I will present the synthesis of Fe1-xMnxSi NWs by a chemical vapor deposition (CVD) method and their respective magnetic and electrical characterizations.

387

Masso-Ferret, Roberto

Bibek Thapa - Physics, University of Puerto Rico, Rio Piedras campus; Kiran Dasari - Physics, University of Puerto Rico, Rio Piedras campus; Ratnakar Palai - Physics, University of Puerto Rico, Rio Piedras campus

Physics

GROWTH AND CHARACTERIZATION OF TANTALUM OXYNITRATE THIN FILM FOR SOLAR WATER SPLITTING

The aim of our research was to develop Tantalum Oxynitrade TaON compounds with good semiconducting properties. Our study was focused on growth, optimization, and characterization of thin film nanostructures of TaON on Si and Pt/Si substrates by sputtering deposition techniques. Structural, electric, and optoelectronic properties of TaON thin films were studied using various characterization techniques. The crystalline structure of the films was analyzed using X-ray Diffraction XRD. In order to understand the conduction mechanisms of the samples, we performed current-voltage characteristics. Hall Effect measurements were done on the samples in order to determine band gap and charge carrier’s mobility. Using REGAKU Altima iii X-ray difractometer in the Cu-K? ?=1.540 Å radiation the pattern of TaON films was recorded. It was compared with the PCPDF #72-2067 and found that the films are polycrystalline. The XRD pattern was indexed with hexagonal crystal structure. I-V curves were collected for one of the samples of TaON on Pt/Si. The best growth conditions for our sample were obtained when the proportion of Oxygen-Nitrogen was less than 15% Oxygen and more than 85% Nitrogen. The Hall Effect experiment of TaON on Pt/Si could not be done because the platinum is more conductive than the TaON films. TaON was then grown on glass in order to make the Hall Effect experiment. We want to use the TaON on glass to obtain the bad gap by using a UV Transmission Spectrometer. With these results we are contributing to the development of compounds with good semiconducting properties.

Palomino-Garate, Javier

Palomino, Javier - Physics, University of Puerto Rico, San Juan, PR 00931, United States; Dorvilien, Valerio - Physics, University of Puerto Rico, San Juan, PR 00931, United States; Weiner, Brad R. - Physics, University of Puerto Rico, San Juan, PR

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00931, United States; Morell, Gerardo - Physics, University of Puerto Rico, San Juan, PR 00931, United States

Physics

Silicon Nanowires Conformally Coated with Ultrananocrystalline Diamond for Lithium-Ion Battery Anodes

Silicon nanowires (SiNWs) were uniformly decorated with ultrananocrystalline diamond (UNCD) by a novel route using paraffin wax as seeding source, which is more effective in the diamond nucleation than traditional methods. These one-dimensional UNCD decorated SiNWs (UNCD/SiNWs) exhibit diameters in the range of 100 to 150 nm and a UNCD grain size of ~5 nm. The films were used for lithium-ion battery (LIB) anodes, where UNCD coating provide effective conduction channels for both electrons and Li-ions and protect the integrity of SiNWs by featuring electrochemical inertness and mechanical strength. The cyclic voltammetry studies show redox peaks for Si consistent with lithium insertion/extraction, indicating good reversibility over extensive cycling. Electrochemical test showed that UNCD/SiNWs electrodes can deliver an initial high discharge capacity of ~1270 mAh/g and a reversible capacity of ~415 mAh/g over 50 cycles. After electrochemical cycling, the UNCD/SiNWs films showed very few negligible cracks formed due to high volumetric expansion of the silicon during lithiation. However, the film still had good contact with the Cu substrate and delamination was not detected. Therefore, UNCD/SiNWs hybrid structure grown directly on current collector (Cu), represents a promising anode material for rechargeable LIBs with high energy density and long cycling stability.

Paulino-Cordero, Leandro

Hernández, José - Physics, UPR-RP; Fonseca, Luis - Physics, UPR-RP

Physics

Synthesis of MoO3 Microbelts with Implanted Pt for Gas Sensing

Gas sensors based on semiconducting metal oxides are commonly used in the markets of automotive, aerospace and logistic applications due to their stability and favorable response while monitoring toxic and combustible gases; being the main

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drawback the operating temperature. Semiconducting material MoO3 is highly sensitive to NO2, NH3, CO, H2, among others. Ion implantation of Pt have been performed on exfoliated MoO3 to enhance sensitivity and reduce working temperature.

Rivera-Vazquez, Rebeca

Javier Palomino - Physics, University of Puerto Rico, San Juan, Puerto Rico, United States.; Deepak Varshney - College Of Natural Sciences, Univ of Puerto Rico, San Juan, PR, United States.; Brad R. Weiner - Chemistry, University of Puerto Rico, San Juan, Puerto Rico, United States.; Gerardo Morell - Physics, University of Puerto Rico, San Juan, Puerto Rico, United States

Physics

Ultrananocrystalline Diamond-Coated Silicon Nanowires for Lithium-Ion Batteries

Silicon nanowires (SiNWs) were conformally coated with ultrananocrystalline diamond (UNCD) by a novel route using candle wax as seeding source, which is more effective in the diamond nucleation than traditional methods. These one-dimensional UNCD decorated SiNWs (UNCD/SiNWs) exhibit diameters in the range of 100 to 150 nm and a UNCD grain size of ~5 nm. Bare SiNWs and UNCD/SiNWs were used in lithium-ion battery (LIB) anodes, where UNCD coating provide effective conduction channels for both electrons and Li-ions and protects the integrity of SiNWs by featuring electrochemical inertness and mechanical strength. The cyclic voltammetry studies show redox peaks for Si consistent with lithium insertion/extraction, indicating good reversibility over extensive cycling. Charge-Discharge tests showed that bare SiNWS can deliver an initial discharge capacity of ~740 mAh/g and stable capacity of 255 mAh/g, however the UNCD/SiNWs electrodes supply an initial high discharge capacity of ~1270 mAh/g and a reversible capacity of ~450 mAh/g over 50 cycles. No visible cracks were found on the UNCD/SiNWs anode material after extensive Li alloying/dealloying, the anode retained its good contact with the current collector, and no anode paring was observed. Thereby, the performance of LIBs based on silicon can be enhanced by implementing the UNCD/SiNWs hybrid structure grown directly on current collector (Cu), which represents a promising anode material with high energy density and long cycling stability.

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Ruiz-Reyes, Angel

Hernández. José A - University of Puerto Rico-Río Piedras; Ángela Luis - University of Puerto Rico- Río Piedras; Fonseca, Luis - University of Puerto Rico- Río Piedras

Physics

Semiconductor magnetic nanowires, synthesis and characterization.

We report the synthesis of FeMnSi nanowires via chemical vapor deposition (CVD). Magnetic chatacterization indicates that the nanowires posses a remnanent magnetization of 2 x 10-03 emu at room temperature. The nanowires thickness ranged between 100nm and 200 nm. XRD and Electron Diffraction measurement were made to obtain the crystal properties of the nanowires. EDS characterization confirmed the presence of Manganese in the nanowires. Electrical test shows that the nanowires behave like a semiconductor featuring a resistance of ~307 ? at 130 K and ~282 ? at 282K. The comparison between the magnetic properties of these nanostructures and Mn-ion implanted FeSi samples is discussed.

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Sajjad-Na, Muhammad

Sajjad, Muhammad - Institute of Functional Nanomaterials UPR-RP; Mendoza, Frank - Institute of Functional Nanomaterials UPR-RP; Tej, Limbu - UPR-RP; Xianping Feng - UPR-RP; Weiner, Brad R. - Institute of Functional Nanomaterials UPR-RP; Morell, Gerardo - Institute of Functional Nanomaterials UPR-RP

Physics

Physical Properties of Graphene/BNNSs Heterostructures; Advance in 2D Functional Nanomaterials

Free standing graphene is a highly conducting material, full of functionalities, suitable for enormous practical applications. On the other hand, for device architecture, when graphene transferred to the substrates e.g. Si, SiO2, it is highly disordered, exhibiting poor characteristics that limits its presence in numerous electrical devices. Therefore, it is pre-requisite to find a substrate that will help to maintain characteristics of a suspending graphene. In this subject, we selected boron nitride nanosheets (BNNSs) as a substrate material for graphene to retain its intrinsic properties. Due to identical crystal structure and similar lattice parameter to that of graphene, BNNSs often known as white graphene. BNNSs provide highly flat surface to grow wrinkle free, less disordered graphene with better functionality. BNNSs were synthesized by short-pulse laser-plasma deposition while graphene was synthesized by hot filament chemical vapor deposition (HFCVD). HFCVD method was preferably applied to avoid sputtering of atomic layer BNNSs. We also synthesized bi-layer graphene on copper substrate and transferred it to BNNSs using conventional mechanical method e.g. poly-methyl meth-acrylate. The crystalline quality of the graphene/BNNSs heterostructures was evaluated by Raman spectroscopy mapping in order to analyze the phonon-phonon interactions between the layered structures. The physical properties of the films were carefully studied by: sheet resistance, thermal conductivity, band-gap, scanning electron microscopy, X-ray photoelectron spectroscopy, and transmission electron microscopy.

Santillan-Mercado, Jaime

Jaime Santillan - Physics Department, UPRRP; Ratnakar Palai - Physics Department, UPRRP

392

Physics

Synthesis and study of CuO nanowires for potential applications

High efficiency and low-cost solar cells fabrication have been key point of intensively research of scientists during the last years. One of the processes that occur when sunlight interact in photovoltaic cells is that higher-energy photons deliver much more energy than needed to excite an electron, and the excess is given off as waste heat rather than desired electrical current. Recently on April, 2014 was published an updated listing of the highest efficiencies for a range of photovoltaic cells, showing the limit of 25% efficiency that can be achieved in a solar cell designed with a crystalline silicon under the global AM1.5 spectrum. Nanotechnology promises to be the tool to provide new materials that can exploit traditional energy sources in more efficient and cost-effective way. Synthesis of CuO nanowires, p-type, is proposed to be an inexpensive and easily scalable component of solar cells and worthy to be studied.

Sharma-Kumar, Yogesh

Sharma Yogesh - Department of Physics and Institute for Functional Nanomaterials; Pavunny Shojan - Department of Physics and Institute for Functional Nanomaterials; Katiyar Ram - Department of Physics and Institute for Functional Nanomaterials

Physics

Co-existance of unipolar and bipolar resistive memory switching in Pt/LaHoO3/Pt memory cell

Pulsed laser deposited amorphous LaHoO3 thin films exhibit both unipolar as well as bipolar switching characteristics which do not depends on the polarity of applied voltages. Such switching can be considered advantageous due to faster switching speed, better uniformity (features of bipolar switching), and high integration density (feature of unipolar switching), which can potentially serve the advanced application scopes of resistive random access memories (RRAMs). We investigated the nonvolatile resistive switching (RS) in Pt/ LaHoO3/Pt device with all four possible modes (I. Positive unipolar, II. Negative unipolar, III. Posive bipolar, and IV. Negative bipolar) with RON/ROFF ratio in the range of ~ 105-106. X-ray

393

photoelectron spectroscopy studies combined with temperature dependent switching characteristics divulged the formation of mixed conductive nanofilaments consisting metallic Ho atoms and oxygen vacancies in the low resistance state (LRS). Detailed analysis of current-voltage relationship further confirmed the formation of conductive filaments on the basis of observed Ohmic conduction in ON-state. Simmons modified Schottky emission was ascribed to be the dominant conduction mechanism in OFF-state of the device. We will present the aforementioned properties of these memory cells and will discuss the intended nonvolatile memory applications of this novel high-k dielectric material in detail.

Belfleur-Saint-Julien, Luxene

Raman spectroscopic characterization of the self-assembly of guanosine derivatives

Supramolecular chemistry offers convenient strategy to construct sophisticated systems towards self-assembly of guanosine derivatives to overcome current challenges in biomedicine. Although there are have been great progress in that field, there is a need for alternative nanomaterials and versatile tools to detect their presence in biological environments. Our focus in this area focuses on the development of supramolecular G-quadruplexes (SGQs) systems made from of 8-aryl-2’-deoxyguanosine (8ArG) and 8-arylguanosine (8ArGu) derivatives. Some of these SGQs have shown stimuli-responsive behavior leading to the formation of higher order assemblies we term Supramolecular Hacky Sacks (SHS), which are capable of encapsulating a variety of guests like doxorubicin anti-cancer drug, DNA and proteins. In order to gain a deeper understanding of these supramolecules, we will characterize them by Raman spectroscopy and we expect this information to enable follow up studies of these systems inside cells. We will present the synthesis and characterization of 8ArG derivatives with Raman probes (e.g., alkynyl-, cyano-groups) in addition of studies of their self-assembly and stimuli-responsive properties using techniques like 1D/2D NMR, UV/Vis spectroscopy, molecular modeling, DLS, DSC, among other. This strategy should advance knowledge in the development of novel nanotechnologies to treat diseases by understanding the role of a supramolecule inside a cell.

394

Dasari, Kiran

Dasari Kiran - Department of Physics, University of Puerto Rico; Bibek Thapa - Department of Physics, University of Puerto Rico; Ratnakar Palai - Department of Physics, University of Puerto Rico

Growth dynamics and micro-structural and optical properties of high indium content InGaN thin films grown at High temperatures for visible applications

High indium content InGaN alloy materials are promising for the wide range of applications such as optoelectronics, spintronics, light emitting diode and lasers in the visible range. The growth of the high quality high In content InGaN is still be a great challenge because of the growth difficulties like phase separation, In segregation, and composition inhomogeneity. In the present study, we have successfully grown the high In content InGaN alloys at high growth temperatures directly on the c-sapphire substrates without any buffer layer using molecular beam epitaxy (MBE) under different growth conditions. The morphology of the thin films has been tuned by changing the substrate temperature (Ts) from 650 °C to 900 °C. The reflection high energy electron diffraction (RHEED) has been employed during and after the growth to understand the growth mechanism and dynamics. The samples grown at 900 °C are single phase with high degree of crystallinity, whereas the samples grown between 650-800 °C shows the presence of small InN (0002) unwanted phase. The existence of the InN (0002) phase can be due to the lower kinetic energy and higher reactive tendency of the adatoms to replace the Ga site and this will be explained more in detail in the presentation. The sample grown at 900 °C showed 3D nanocolumn surface, whereas the samples grown between 650-800 °C showed 2D-like well defined films. The high resolution scanning electron microscopy (HRSEM) studies showed that there is a significant change in the surface morphology with increasing temperature. It also revealed that there is a transform in growth process at 900 °C. The sample grown at 900 °C showed a defect free visible PL at 605 nm, while the sample grown between 650-850 °C showed emission at ~558-567 nm. The sample grown at 900 °C showed enhanced PL compared to the other samples. This could be due to the minimization of the defects as a result of change in the growth morphology. It is possible that in nanocolumn growth might have suppressed the propagation of the lattice strain. Also broader FWHM of the excitonic band indicating the lower InGaN material quality for samples growth between Ts=650-800 °C compared to InGaN grown at Ts=900 °C. Raman, HRTEM, and electrical characterization has been studied for the better understanding of the growth dynamics and properties and will be discussed in details in the presentation.

Documents

50 - PR-LSAMP · Amelia Babilonia, Chemistry Department José Terrón, Scientific Illustrator Nivea Santiago, Acting Director, CITEC Edwin Viera, CITEC Samuel Suleiman,CITEC Néstor