Trinity University · Giovanni Giammanco Experiments and Simulations of . Escherichia coli. Chemotaxis . Healy & Nguyen Roland Green & Stefan Schluter Fast-SLAM implementation with

Trinity University Summer Undergraduate

Research Conference

July 23-4, 2014

30th Annual

Department of Chemistry Research Symposium

9th Annual Summer Undergraduate

Research Conference

Conference Schedule At-a-Glance

Wednesday, July 23, 2014 3:30 – 5:30 p.m. Poster Session 1 Location: Center for Sciences & Innovation Atrium

Thursday, July 24, 2014 8:00 – 9:50 Chemistry Symposium Session A Northrup Hall 040

8:00 – 9:45 General Session A CSI 437

10:00 – 11:45 Chemistry Symposium Session B Northrup Hall 040

10:00 – 11:45 General Session B CSI 437

11:45 – 1:15 Poster Session 2 Chapman Lobby

11:45 – 1:15 Lunch for presenters & mentors Great Hall, Chapman

1:15 – 3:00 Biochemistry & Molecular Biology Showcase Chapman Auditorium

1:15 – 2:45 General Session C CSI 437

1:15 – 3:10 Chemistry Symposium Session C Northrup Hall 040

3:00 – 5:00 General Session D CSI 437

3:25 – 5:00 Chemistry Symposium Session D Northrup Hall 040

Poster Presentations

Poster Session 1 ● Wednesday 3:30-5:30 PM ● Center for Sciences & Innovation Atrium

Presenter(s) Title Mentor(s) Franchesca

Escapita Measuring the Impact of the San Antonio Education

Partnership's Services on Student Access and Success Perez

Alyssa Fink Do Corridors Maintain Genetic Diversity? A Study of Urban Texas Spiny Lizard Populations

Ribble & Johnson

Elizabeth Gilbert

Two families are better than one: Understanding kinship in LGBT Mardi Gras associations Stone

Giovanni Giammanco Experiments and Simulations of Escherichia coli Chemotaxis Healy &

Nguyen Roland Green

& Stefan Schluter

Fast-SLAM implementation with Low Cost Consumer Robots Nickels

Nicola Hill Analysis of finite fold geometry and variations in strain based

on structural position: a case study from the Stillwell anticline, west Texas

Surpless

Eric Kang & Niti Nararidh CSI Building Official Robot Guide Nickels

Sean Kinahan Analysis and High-throughput Sequencing of the Naked Mole Rat Transcriptome Hibbs

Grace Mabry & Lindsey Yazbek

Sedimentology and Depositional Environments of Cyclic Microbial Bearing Strata of the Cambrian Point Peak Member

of the Wilberns Fm., exposed along the Llano River, Mason County, TX

Lehrmann

Matthew Mitts Female Testosterone and Aggression: Weapon of Choice for the Female American Goldfinch (Spinus tristis) Murphy

Mark Mlella Implications of fracture characteristics for fluid flow within

fold systems: a case study from the Stillwell anticline, west Texas

Surpless

Ismerai Monreal

The Unusual Suspects: The Reasons behind Human Rights Violations in Developed Countries Aloisi

Tae Sakong ApoE in Astrocytes: From Gene Expression, to Production, and Secretion Roberts

Rebecca Schauer

2D and 3D Computer Modeling of the Stillwell Anticline Fold System: Testing Models of Fold Formation Surpless

Christian Tovar-Vargas

Narcissists are Less Prone to Come Up Short (Literally) Under Pressure Wallace

Elizabeth Van Horn &

Austin Philippe

Assessment of Cedar (Juniperus ashei) Removal on Native Grassland Re-establishment in the Texas Hill Country Lyons

Sophie Wardle The Effect of Perceived Social Competition on Corticosterone Levels in the American Goldfinch Murphy

Jonathan Zeitzer

The Effects of UV Radiation on Kale Growth in a Hydroponic System Shinkle

Poster Session 2 ● Thursday 11:45 AM -1:15 PM ● Chapman Center Lobby

Presenter(s) Title Mentor(s) Jogen Atone Investigating the Mechanism for ApoE Secretion by Astrocytes Roberts

Hanna Batory & Amanda Nguyen

The Effect of Modulating Neuronal Membrane Toxicity of Beta Amyloid

Roberts, Aminian &

Elaydi Greg Bustamante Hydrodynamics of Sessile Choanoflagellates Nguyen Imon Ferguson & Hamilton Rogers

Measuring the Effects of Biomixing with Forced Rayleigh Scattering

Healy & Spiegel

Clayton Ford Sedimentology and Depositional Environments of the Transition

Interval Between the Non-Microbial Bearing Strata and Large Microbial Reefs in the Cambrian Wilberns Fm., Mason County, TX

Lehrmann

Sara Guarino Developmental Changes in Activity Levels for a Killer Whale Calf and Her Mother Across Three Years of Life Hill

Jessica Heppard Do Female Siamese Fighting Fish (Betta splendens) Modulate Their Investment in Aggression Depending on Resource Value? Murphy

Tyler Howard, Angeline Bottera,

& Meagan Oglesby

Children’s Visual Attention to Dynamic Events and Their Early Verb Learning Childers

Nathan King Group Size, Sociality, and Social Connectivity, and its Relationship

to Foraging Success in the Black-crested Titmouse (Baeolophus atricristatus)

Murphy

Caroline Kuhn Ideology or Placating? Cognitive Load and Latinos’ Attributions for “the Gap” Sperling

Julianna Kurpis Using Photoreceptor Mutants to Determine how Ultraviolet Radiation is Sensed by Plants Shinkle

Gabriella Montemayor Reducing Overpopulation by Offering Low-Cost Health Services Davis

Mary Moscosa Disciplines as a Cultural Factor and Its Contribution to CEO Success or Failure Yang

Jamal Murray The Effects of Sexual Selection on the Copulatory Morphologies of Tropical Lizards Johnson

Sarah Pickett The Effects of Shortwave UV-B on Native Texas Grasses in a Natural Environment Shinkle

Yanjiao Qin The Triassic Marine Reptile Keichousaurus hui of Western Guizhou Province, China: Sexual Dimorphism and Environmental Conditions

Leading to Exquisite Fossil Preservation Lehrmann

Kelly Seeber Development and Validation of a Social Desperation Inventory McIntyre

Jake Stercula Body Temperature and Brain Lipid Composition in Puerto Rican Anole Lizards Johnson

Ashley Tessnow &

Tess Macapinlac

Utilizing Regional Growth Rates to Model Mammalian Species Distribution

Ribble, Hasfura, &

Elaydi Alejandra Trigoso

Medieval Enameling Techniques: Research, Re-Creation & Studio Application Goeckler

Oral Presentations

Session A ● Thursday, 8:00-9:45 AM

Moderator: Dr. Hibbs Center for Sciences & Innovation 437 (Treehouse)

Time Presenter(s) Title Mentor(s)

8:00 AM Douglas

Steinman & Josh Humphreys

On the probability of the development of Bateson-Dobzhansky-Muller incompatibilities that incorporates protein interaction networks

Olofsson

8:15 AM Dallas Akins Superluminal Speeds in Helical Quasar Jets Hough

8:30 AM Duncan Frasch Measuring Diffusion of Methyl Red in Polar Solvents using Forced Rayleigh Scattering. D. Spiegel

8:45 AM Benjamin Gomez & Andrea Lee Modern Snail: Starting a Student Start-Up Martinez

9:00 AM Michelle Oberndorf

How Do Lizards Communicate? Static and Dynamic Visual Displays in Crested Anoles Johnson

9:15 AM Jacob Luber Utilizing Machine Learning in Computational Biology and Classics Hibbs

9:30 AM Samuel Simoneau & Robert Hure

Surface Plasmon Enhance Fluorescence Using Gold Nanogratings Steele

Session B ● Thursday, 10:00 – 11:45 AM Moderator: Dr. Soto

Center for Sciences & Innovation 437 (Treehouse)

Time Presenter(s) Title Mentor(s) 10:00 AM Isaiah Ellis Hunting Buffalo in Oklahoma: Capitalism and

Cultural Representation in Indian Casinos Tarango

10:15 AM Giovanna Espinoza

Empowerment of the U.S. Latina: The Role of Higher Education in the Films Real Women

Have Curves (2002) and Mosquita y Mari (2012)

Urquijo-Ruiz & Blanco-Cano

10:30 AM Sonny Luna How Students With Learning Differences Respond to Art Education Delgado

10:45 AM Arnulfo Tunon Assessment of Peripheral Immune Parameters as Non-Invasive Measure of VNS Efficacy: A

Pilot Study O’Connor

11:00 AM Rosa Olivares Fiesta Fundraising: Filling the Gaps of AIDS Service Organizations in San Antonio Stone

11:15 AM Jaferaly Hooda The Culture Industry Online Norman

11:30 AM Melissa Smallwood

Synaptic Troubleshooting: Making the Connection between Autism and Labor &

Delivery Drugs Williams

Session C ● Thursday, 1:15 – 2:45 PM Moderator: Dr. Yang



1:15 PM Nicholas Toffoletto

Reducing Charged Based Noise in Gravitational Wave Observatories Ugolini

1:30 PM Gregory Walls Experiments and Simulations of Escherichia coli Chemotaxis

Healy & Nguyen

1:45 PM Elizabeth Hartson

Aspens, Monarchs, and Terraforming: Interdisciplinary Study of

the Local and Global Perspectives in International Climate Change Novels and Ecology.

Sullivan

2:00 PM Ngoc-Tam Personal cultures and their impact on Sino-US female CEOs’ success and/or failure to become

global managers Yang

2:15 PM Mariah Wahl The Bible in the Final Novels of Philip K. Dick Dupertuis

2:30 PM Nicole Vreeland Environmental Activism Through Art Ward

Session D ● Thursday, 3:00 – 5:00 PM Moderator: Dr. Phillips



3:00 PM Kelly Hewes Exploring the effects of exercise on cognitive dysfunction in the marmoset EAE model Phillips

3:15 PM Liam Fox Quantum Few-Body Problems on a GPU Mehta 3:30 PM Connor Morehead Quantum four-particle problem on a line Mehta 3:45 PM Evan LeGros Subsumption Data Strictures Fogarty

4:00 PM Kristen Schultz & Ann Adams

Modeling the Competitive Dynamics Between Native and Invasive Grasses Under Varying Light

Conditions

Lyons & Kwessi

4:15 PM Cassandra Watson &

Katherine Walls

Modeling Epithelial cell Migration and the role of ZO-1 in Migration

King, Balreira, & Hasfura-Buenaga

4:30 PM Austen Hall,

Bryan Shrock, & William Garvie

What is Computation? Brown & Fogarty

30th Annual Department of Chemistry Research Symposium

Session A ● Thursday, 8:00-9:50 AM Moderator: Dr. Urbach

Northrup Hall 040


8:00 AM Molly Hogsett Synthesizing and Optimizing Chemical Modifiers for the Rieske Protein

Hunsicker-Wang &

Mills

8:15 AM Chris Hertz Probing the Role of the Amino Acids Adjacent to the

Ligating Histidines of the [2Fe-2S] cluster of the Rieske Protein

Hunsicker-Wang

8:30 AM Meagan Coffer & Josh Perkins

Synthesis of the Precursors of Benzannulated Bis-cycloheptatrienide Dianions Mills

8:45 AM Kelsey Kirkman & Rachel Tchen

Characterization of Antiaromaticity of Phenyl Substituted Bis-Benzocycloheptatrienide Dianions Mills

9:00 AM Elisabeth Purdy Hydrogenation of Phenylacetylene over Supported Gold Catalysts Chandler

9:15 AM Ryan Lord Förster Resonance Energy Transfer on Gold Self-Assembled Monolayers Chandler

9:30 AM Adwaith Mani & Todd Whittaker

Effects of Water on CO Oxidation and Adsorption on Supported Au Nanoparticle Catalysts

Chandler & Pursell

Session B ● Thursday, 10:00 – 11:45 AM Moderator: Dr. Bachrach

Northrup Hall 040

Time Presenter(s) Title Mentor(s) 10:00 AM Hamilton Lee Co-Host Mediated Divalent Recognition of Peptides Urbach

10:15 AM David Leach Sequence-Specific, Nanomolar Peptide Binding via Folding and Inclusion of Neighboring Residues in

Cucurbit[8]uril Urbach

10:30 AM Zach Nickle Exploring Flatter ExBox Host Analogs Bachrach 10:45 AM Caileen Tallant Exploring Wider ExBox Host Analogs Bachrach

11:00 AM Natalie Seitzman XRF Analysis of Spanish Colonial Alamo Frescos Bushey

11:15 AM Joel Adablah High resolution imaging of fused-silica capillaries

containing a porous polymer laurel acrylate monolith using scanning electron microscopy

Bushey

11:30 AM Nico Dwarica & Zach Tuten

Investigating Diffusive and Convective Vapor Transport Mechanisms for the Evaporation of

Hydrocarbons Kelly-Zion & Pursell

Session C ● Thursday, 1:15 – 3:10 PM Moderator: Dr. Chandler

Northrup Hall 040


1:15 PM Leslie Cook,

Shelby Luikart, & Lindsey Ulin

Characterization Studies of Gold Nanoparticle Catalysts Using the Selective Oxidation of Benzyl

Alcohol Chandler

1:45 PM Allison Levy NMR Classification of Fossilized Plant Exudates Lambert

2:00 PM Jasmine Rodriguez

Determination of Piperidine Structure by NMR Spectroscopy Lambert

2:15 PM Brady Iba & Yizhou Zhao

Thermodynamic Studies of Retention on a Lauryl Acrylate Porous Polymer Monolith Bushey

2:30 PM Pooja

Bollampally & Rohit Sampat

Characterization of Lauryl Acrylate Porous Polymer Monolith Stationary Phase In Capillary

Electrochromatography Through Diffusion Study Bushey

2:45 PM

Rachel Felger, Jemma

Ferguson, Janie Thompson, &

Miguel Webber

The Effect of Phenyl Substitution on Delocalization in Antiaromatic Bis-indenylidene Dications Mills

Session D ● Thursday, 3:25 – 5:00 PM Moderator: Dr. Mills

Northrup Hall 040


3:25 PM Sam Lee Exploring the Mechanism of the Nucleophilic Substitution Reaction of Peroxides Bachrach

3:40 PM Alex Huther &

Caroline Kelleher

Alkyne hydrogenation over supported Au and Au-M catalysts Chandler

4:00 PM Cameron McKay &

Lucas Poliak

Exploration of Delocalization Patterns in Antiaromatic Bis-indenylidene Dications Mills

4:15 PM

William Mobley & Vanessa Romano

Synthesis of Precursors to Antiaromatic Thiophene Cations Mills

4:30 PM Nathan Webber Investigation of the Effects of Overall Charge State

on Ferredoxin Cluster Reduction Potential in the Thermus Thermophilus Rieske Protein

Hunsicker-Wang

4:45 PM Matt Ponthier Probing the Factors that Affect Reduction Potential in the Thermus Thermophilus Rieske Protein

Hunsicker-Wang

Biochemistry & Molecular Biology Showcase

Thursday, 1:15-3:00 PM Moderator: Dr. Hunsicker-Wang

Chapman Center 126 (Chapman Auditorium)


1:15 PM Carolyn Young Insulin-Specific Inhibition of Insulin-Degrading Enzyme Using a Synthetic

Receptor Urbach

1:30 PM Ron Davenport-Dendy

Computer Simulations of Beta-Amyloid Dimer Interactions with Lipid Rafts Cheng

1:45 PM Hudson Smith Attempted Synthesis of Fluorescent and Benzophenone Labeled Metformin Analogs Martinez

2:00 PM Liezelle Lopez Isolation and Characterization of a Mixed

Disulfide Intermediate Between Thermus Thermophilus Sco and CuA

Hunsicker-Wang

2:15 PM Ambrose Paige Probing the 3 Cysteine, 1 Histidine Ligation Environment of a [2Fe-2S] Cluster Hunsicker-Wang

2:30 PM Sara Vivatson Characterization of a Cucurbit[7]uril-Rhodamine Conjugate as a Chemical Sensor Urbach

2:45 PM Amy Grice Development of a Cellular Probe Based on a Synthetic Receptor Urbach

Poster Session 1 Presentation 1 Franchesca Escapita Advisor: Ms Perez

Measuring the Impact of the San Antonio Education Partnership on Student Access and Success

According to the 2012 census, only 34.6 percent of working age adults in Texas holds a two-or-four year college degree. In San Antonio, the American Community Survey (2011) reveals that 32 percent of all adults in San Antonio have an associate’s degree or higher. With the nation’s demographics projected to look like San Antonio’s in the near future, low postsecondary degree attainment is an issue many leaders in San Antonio are trying to ameliorate. Many researchers agree that degree attainment rates can be increased by focusing on developing programs to help students get into college, increasing financial aid for students, and having various leaders from the community come together to focus on student success in college. For my research I am evaluating the San Antonio Education Partnership, the largest local access and success direct service provider, to develop effective ways to document and communicate their impact on increasing college student attainment rates in San Antonio.

Funding Source: Trinity University McNair Scholars Program

Poster Session 1 Presentation 2 Alyssa Fink Advisors:

Dr. Ribble & Dr. Johnson

Do corridors maintain genetic diversity? A study of urban Texas Spiny Lizard populations

San Antonio, Texas has recently set aside natural areas and corridors (i.e., green-belts) connecting them for conservation purposes (http://www.sanantonioriver.org/). These corridors provide an excellent local opportunity to assess the effectiveness of corridors for population management. Here, we study the population genetics of the Texas Spiny Lizard (Sceloporus olivaceus) to determine if lizards from populations in isolated urban park areas are genetically less variable than those in areas connected by corridors and those in natural rural areas, and therefore assess whether corridors improve the long-term sustainability of lizard populations in these urban environments. We collected 106 lizard tissue samples from 5 populations. Preliminary population genetic analyses indicate significant differences between populations that are relevant to isolation and connections, and are important for conservation efforts.

Funding Source: Arnold and Mabel Beckman Foundation

Poster Session 1 Presentation 3 Elizabeth Gilbert Advisor: Dr. Stone

Two families are better than one: Understanding kinship in LGBT Mardi Gras associations

This study focused on the relationships formed within lesbian, gay, bisexual, and transgender (LGBT) social groups, or “krewes”, organized around the Mardi Gras season. These krewes are clubs which put on a formal ball during Mardi Gras, along with other events throughout the year. This study focused on krewes formed by members of the LGBT community, specifically on one krewe in Baton Rouge, Louisiana and three krewes in Mobile, Alabama. This data was collected through over 30 formal and informal interviews with LGBT krewe members and ethnographic field notes taken at krewe gatherings during a two-week fieldwork trip.

Kath Weston famously argued that often, in the LGBT community, “Families We Choose” are established to replace relationships with estranged biological family. In anthropology, the relationships between people that are related are often just as important as relationships structured around other, more complicated, non-biological relationships. It is the goal of this paper to challenge Weston’s view and illustrate that complex relationships within LGBT Mardi Gras organizations can be understood as a pseudo-family that complements rather than replaces biological family.

Funding Source: Andrew W. Mellon Foundation

Poster Session 1/ General Session C

Presentation 4

Giovanni Giammanco & Gregory Walls

Advisors: Drs. Healy &Nguyen

Experiments and Simulations of Escherichia coli Chemotaxis For certain bacteria such as Escherichia coli, bidirectional propeller-like rotary

motion of flagellar filaments results in the net movement of the cell through gradients of chemoattractant molecules toward areas of higher attractant concentrations. Directional switching of the flagellar motor is governed by a phosphorelay circuit that transfers phosphoryl groups from donor to acceptor proteins; and protein phosphorylation state is controlled by binding of chemoattractants to specific receptors. The two-dimensional hydrodynamics of cell motility is modeled by coupling the chemotaxis equations of a simplified phosphorylation cascade with the method of regularized Stokeslets of the fluid motion. For a slow enough diffusion rate of the attractant gradient, simulations have consistently resulted in a biased random walk of the majority of cells towards the highest concentration of attractant, representative of chemotactic behavior. Using GFP expressing E. coli and confocal microscopy, the motion and chemotaxis behavior can be tracked and analyzed to validate a model. The results from the model and experiment demonstrate how the phosphorylation affects the run and tumble mechanism of swimming bacteria.

Funding Source: NSF UBM-IRBM

Poster Session 1 Presentation 5 Roland Green & Stefan Schluter

Advisor: Dr. Nickels

Fast-SLAM Implementation

with Low Cost Consumer Robots

A robot is defined as a machine that is able to complete complex series of actions automatically. Autonomous robots are ones designed often times to be able to move without being given prior knowledge of the environment they are placed in such as maps. A key issue in the area of autonomous robot navigation is what is known as the “chicken or egg” problem, where in order for a robot to move effectively, it must be able to create a map of the environment (mapping) which requires an accurate estimate of pose (localization), and in order for the robot to find its position and orientation within the environment, the robot must have an accurate map. When done at the same time, this is known as Simultaneous localization and mapping, or SLAM. To overcome this obstacle, the implementation of a Fast-SLAM algorithm was chosen for its computational speed as compared with other SLAM approaches. Fast-SLAM uses a combination of data received from sensors on the robot, odometry from the robot, and a mathematical construct known as a particle filter to account for errors that naturally occur with odometry, and noise with sensor readings. The particle filter itself represents guesses of potential robot locations, and rates each location based on how well it matches predicted sensor readings. Each particle also has a set of Extended Kalman Filters to estimate the location and bearing of landmarks. Fast-SLAM was used to map an environment in simulation using the Player/Stage software package, and on a tabletop obstacle course using the affordable consumer E-Puck robot from GCtronic, with hopes of building a foundation for more SLAM related research at Trinity University.

Funding Source: FASTER Grant from NSF

Poster Session 1 Presentation 6 Nicola Hill Advisor: Dr. Surpless

Analysis of finite fold geometry and variations in strain based on structural position: a case study from the Stillwell anticline,

west Texas The analysis of folds and fractures on the surface is critical for our understanding of

subsurface fault geometry and evolution. A well-exposed fold in west Texas, the asymmetric Stillwell anticline, is NW-trending, 8 km long, and exhibits a left-stepping en echelon pattern with three prominent segments. The highest fold amplitudes are near the center of each segment, with amplitudes that decrease approaching segment boundaries. The deformation of the well-bedded Cretaceous carbonate rocks that define anticline geometries is especially prominent where the anticline has been dissected by erosion. Previous studies suggest that the anticline is cored by a basement-involved fault system that is best modeled using trishear kinematics.

We used field data, field photography, and photogrammetry to compare fold geometries and strain accommodation at different locations along the anticline system. With photomosaics of the forelimb and hinge zone, we documented a range of deformation mechanisms and zones of maximum strain. A high-resolution 3D model of a particularly well-exposed cross-sectional view of the anticline was created using Agisoft Photoscan photogrammetric software. This software enabled us to analyze areas of the outcrop that were inaccessible to better constrain variations in fold and fault geometry and fracture intensity.

We documented significant variation in fold geometries along trend of the anticline system. The northern and southern fold segments exhibited moderately-dipping (20 – 30 degrees) backlimbs, long shallowly-foreland-dipping midlimbs, and steep (>60 degrees) forelimbs. Locations near the central zone of the fold had more gently-dipping (<20 degrees) backlimbs, short midlimbs, and steeply-dipping forelimbs. At all locations, the hinge zone and the forelimb exhibited the greatest strain, consistent with previous 2D modeling results. These structural positions exhibited significant ramp-flat fault geometries, intra-bed faulting, intense fracturing, and zones of brecciation. This study better constrains the distribution mechanisms of strain within a fault-propagation fold system, demonstrates the power of photogrammetry in structural studies, and provides a well-documented model for the interaction of fold segments in complex fault-cored systems.

Funding Source: NSF Award #1220235

Poster Session 1 Presentation 7 Eric Kang & Niti Nararidh Advisor: Dr. Nickels

CSI-Building Official Robot Guide The purpose of the CSI-BORG (CSI-Building Official Robot Guide) is to lay a

foundation for a 2014-15 Senior Engineering Design project that will implement a robotic system to lead tours of the Center for Sciences and Innovation (CSI). The project will start with a robot known as the Turtlebot, which runs the Robot Operating System (ROS), an operating system designed to reduce the complexity of programming a robot. An objective of this research is to implement a system that navigates between different rooms on a single floor of CSI using a known map. A collision avoidance system should also be developed for this robot to avoid unmapped obstacles such as people and furniture. The planning system should also plan routes that avoid regions not detectable with sensors, such as glass walls or manually specified no-go zones.

This summer, we have made significant progress towards this goal: we have a system that will navigate, while avoiding unmapped obstacles, from one location to another. Throughout the following school year this project will be developed further into a fully functioning automated tour-guide for CSI.

Funding Source: Trinity University

Poster Session 1 Presentation 8 Sean Kinahan Advisor: Dr. Hibbs

Analysis and High-throughput Sequencing of the Naked Mole Rat Transcriptome

Recent advances in high-throughput genome sequencing have drastically increased the amount and availability of biological data for research. These new collections of genomics data can be used to predict specific gene and protein involvement in a variety of biological functions, allowing researchers to investigate a range of topics in biology and medicine. However, one drawback of high-throughput sequencing is the sheer volume of data produced, and the inevitable increase in computational power necessary to handle these massive data sets. In this study, advanced algorithms were used to determine gene and protein similarity of various mammals against data collected from the naked mole rat (H. glaber, NMR). Little is currently known about the biological functions of the majority of genes in the NMR genome. By applying various analysis techniques to the NMR genome and transcriptome, and by subsequently compiling analogous datasets, we were able to make thousands of predictions for likely NMR gene analogs in the mouse (M. musculus) and human genomes. The diversity of computational methods and quantity of gene sequence data used has allowed us to broaden the scope of our predictions. Ultimately, our study provides new information that will be important for the continued study of NMR as a model organism, especially in the context of continued investigation into its protein pathways and methods of cancer resistance.


Poster Session 1 Presentation 9 Grace Mabry & Lindsey Yazbek

Advisor: Dr. Lehrmann

Sedimentology and Depositional Environments of Cyclic Microbial Bearing Strata of the Cambrian Point Peak

Member of the Wilberns Fm., exposed along the Llano River, Mason County, TX

With the discovery of oil fields in pre-salt strata of offshore Brazil, interest in lacustrine microbialites has greatly increased. Marine microbial carbonates contain similar features that allow them to serve as powerful analogues for pre-salt microbial hydrocarbon reservoirs. Private ranches of Mason County have made accessible Upper Cambrian microbial reefs along the Llano River allowing for the detailed study. The section is comprised of alternating siliciclastic- and carbonate-rich facies. Silty limestone is interpreted to represent a low-energy intertidal environment based on the presence of interference ripples and lenticular bedding. The heterolithic facies is interpreted to represent a low-energy intertidal environment based on the presence of lamination, ripples with reversing current indicators, interference ripples, and mud cracks. Tidal bundles indicate fluctuation between tidal currents and calm waters during slack tide. The glauconitic siltstone is interpreted to represent oxygenated waters with low current energy in a shallow-subtidal environment based on the occurrence of bioturbation. The microbial facies is interpreted to have formed in a shallow intertidal to subtidal environment with alternating tidal current energies and stenohaline conditions based on alternating grainy and muddy channel fill and stenohaline fauna. The skeletal grainstone-packstone facies is illustrative of a lower energy, open-marine subtidal environment that experienced periods of high energy due to the findings of bioturbation, stenohaline fauna, cross-bedding, and asymmetrical mega-ripples. Many skeletal grains are filled with carbonate mud indicating initial low-energy deposition followed by reworking. The oolite grainstone formed in a high energy, shallow-subtidal, open-marine environment based on cross-bedding and asymmetrical mega-ripples. Azimuths of ripples indicate northeast-southwest directed tidal currents across a shoreline bordering the Llano Uplift.

Alternating siliciclasic- and carbonate-rich beds and high-frequency oscillations in gamma ray levels depict cyclical fluctuations in sea level. An overall upward trend towards greater siliciclastic content reflects long-term sea level fall. The microbial facies dominates the lower carbonate rich and middle mixed carbonate-siliciclastic part of the section. This demonstrates that it is possible for microbial reefs to thrive in the presence of significant siliciclastic flux, only being hindered after a certain threshold is breached.

Funding Source: Shell, Chevron, ConocoPhillips, Statoil

Poster Session 1 Presentation 10 Matthew Mitts Advisor: Dr. Murphy

Female Testosterone and Aggression: Weapon of Choice for the Female American Goldfinch (Spinus tristis)

Testosterone (T) has long been established as a major hormone activator in male aggression. Females also produce testosterone and so selection may act directly on female testosterone levels to mediate aggression, and in females, this aggression may be most important during competition over food or territories. The bill of female American Goldfinches is particularly interesting because female bill color has been shown to signal aggressive status during competitive interactions over food resources, and female bill color correlates with circulating T. Using aviary based dominance experiments, we are testing whether T leads to greater female aggression, and whether there is a causal relationship between circulating plasma testosterone and bill color. To manipulate T, we implanted into focal females crystalline testosterone packed silastic implants (either high dose: 6mm, mid dose: 4mm, control dose: 5mm empty tube). The focal females’ behavior was then assessed using a two-compartment aviary paradigm, wherein one large cage held the focal bird, and a smaller cage within held a stimulus bird. The two females shared access to a small food trough, although 80% of the trough was inside the stimulus bird’s cage, and thus was more ‘monopolized’ by the stimulus bird. We predicted that focal females with greater T would be more apt to approach the shared feeding trough and would spend more time feeding near the stimulus bird. We also predicted that the focal females with greater T would have more colorful bills. Data are currently being analyzed. By testing these relationships, we will test the affect of T on female boldness behavior, as well as test whether bill color reflects up-to-date physiological preparedness of a female to enter into an aggressive encounter.

Funding Source: Texas Ecolab

Poster Session 1 Presentation 11 Mark Mlella Advisor: Dr. Surpless

Implications of fracture characteristics for fluid flow within fold systems: a case study from the Stillwell anticline, west Texas

We performed detailed analysis of fracture orientations and characteristics across the Stillwell anticline, west Texas, a NW-trending contractional fold system that formed during the Laramide orogeny. By documenting fracture characteristics including morphology, calcite fill texture, number of generations of precipitation, fill composition, isotopic signature, and host rock alteration, we are able to place constraints on the evolution of the fluid flow network.

Previous research established that there are four fracture sets in the fold system. These sets trend N (set F1), NE (set F2), ENE (set F3), and NW (set F4). Analysis of these orientations in the context of fold formation revealed that: set F1, present in both folded and unfolded strata, is unrelated to fold formation; the orientations of sets F2 and F3 are consistent with conjugate shear formation during folding; and set F4 is subparallel to the fold axis and appears to be related to bed flexure during folding.

We used field data and rectified field photos to create fracture maps, and we collected core samples of fractures and host rock from the 4 fracture sets using a portable drill. We analyzed high resolution (600 dpi) optical scans and documented features observed in petrographic thin sections. We also utilized a portable XRF spectrometer to determine the compositions of host rocks, alteration halos, and fracture fills, and we interpreted both C- and O-isotope values collected from a large aperture fracture with more than 15 fill events.

Our analysis of fracture characteristics revealed stronger correlation by sample location than by fracture set. Our data imply that: 1) fractures at every location were open for some time prior to calcite precipitation; 2) all fractures at a given location were simultaneously filled by locally-sourced fluids with little isotopic variation; and 3) there is no evidence for significant fluid flow during or immediately after formation of any of the fracture sets. Thus, we hypothesize that fluid flow connectivity would have been maximized, with relatively isotropic flow, during and immediately after fold formation, and that flow-inhibiting precipitation was likely unpredictable, rapid, and localized, making prediction of subsurface flow rates and pathways difficult.


Poster Session 1 Presentation 12 Ismerai Monreal Advisor: Dr. Aloisi

The Unusual Suspects: The Reasons behind Human Rights Violations in

Developed Countries The process by which states fall under the scrutiny of the United Nations (UN)

human rights monitoring mechanisms has been the object of extensive investigation. However most studies have devoted their attention to the “usual suspects”; rogue governments notorious for implementing policies of persecution and aggression of their own citizens. Notwithstanding the gravity of human rights violations committed by “rogue states”, human rights violations are commonly perpetrated by nations that do not fall under the stereotype of governments that would normally violate human rights of their own citizens. In this study we map the type of human rights violations committed by “developed nations” which fall under the scrutiny of the UN treaty based bodies and the interaction between governmental representatives and human rights committees. We posit that most of the developed states that fall under the scrutiny of human rights committees do so because of lacking domestic legislation. We define and rank the aspects and indicators which determine a “developed nation” in order to consider the difference in implementation of legislation as well using the UN Human Development Index ranking. We contend that, although ratification of human rights treaties is an important component of compliance with human rights, vague international human rights standards and a weak international enforcement system, create meaningless commitments, only enforceable by national legislation, by previously changing domestic legislation and aligning it with the international human rights standards.


Poster Session 1 Presentation 13 Tae-Hyun Sakong Advisor: Dr. Roberts

ApoE in Astrocytes: From Gene Expression, to Production, and Secretion

Apolipoprotein E (apoE) is a lipid transport protein that mediates cholesterol transport and clearance within the central nervous system (CNS). The dynamic exchange of apoE between neuronal and non-neuronal cells indicates the fundamental importance of apoE mediated cholesterol transport. Although the e4 allele of apoE is a major genetic risk factor for Alzhemier’s Disease (AD), the mechanism of apoE mediated cholesterol synthesis, transport, or secretion remains to be elucidated. Previous studies in our lab found that in astrocytes, apoE expression changes as a function of age. ApoE expression is low at younger and older ages, but the highest at the middle ages. Interestingly, the inductive effects of estrogen treatment on apoE expression were the greatest at older ages. Thus, this study aims to couple the analysis of apoE expression in astrocytes with cytoplasmic apoE production in addition to secretion. The systematic analysis from gene expression, production, to secretion, will answer at what level of apoE biosynthesis changes with age.


Poster Session 1 Presentation 14 Rebecca Schauer Advisor: Dr. Surpless

2D and 3D computer modeling of the Stillwell anticline fold system, west Texas: testing models of fold formation

The Stillwell anticline is a 500 m wide, 8 km long, well-exposed basement cored fold system in the Big Bend region containing three NW-trending, NE-vergent, left-stepping en echelon segments with flat-ramp fold geometries. The area is characterized by bedded Cretaceous carbonate rocks, with the present-day surface approximately 600 m above the Paleozoic basement. Like most basement-involved, fault-related anticlines of the Laramide orogeny, the Stillwell anticline is characterized by narrow, steeply-dipping forelimbs expanding into gently-dipping backlimbs. We used existing geologic maps, cross-sections of the fold system, and remotely-sensed data to help build models of the fold system with 3D Move (Midland Valley software). These models included 2D and 3D kinematic and mechanical models of the fault-cored fold system to best constrain the formation of the anticline.

3D Move uses geometric algorithms to provide efficient and viable proxies for deformation that follow traditional modeling approaches. This software permits us to test and improve our structural models. With these 2D and 3D models, we can construct valid subsurface interpretations of initial fault geometries that led to the structural geometries that we observe on the surface today. We began our study by building a 3D model of the system through the integration of existing 2D geologic cross sections, construction of additional cross sections from field data, and incorporation of our interpreted subsurface fault geometries. We then used 3D Move’s Unfolding and Move On Fault modules to restore the area to pre-deformation geometries while simultaneously testing our interpretations of the anticline system.

After adjusting our initial fault interpretations based on model results, we successfully constructed a valid, testable 3D model of fault-cored fold formation. These results improve our understanding of the origin and evolution of Laramide age deformational structures in the Big Bend area and will permit us to evaluate lithologic responses caused by the formation and propagation of fault-cored folds in compressional settings.


Poster Session 1 Presentation 15 Christian Tovar-Vargas Advisor: Dr. Wallace

Narcissists are Less Prone to Come Up Short (Literally) Under Pressure

The current research examined how narcissism affects target-shooting performance tendencies under the presence and absence of performance pressure. We focused specifically on undershooting/overshooting, which has received limited research attention. After completing a narcissistic personality measure, participants slid poker chips across a tabletop towards twelve differently labeled target zones in two different rounds. Participants received more points for landing a poker chip in a more distant target zone without going past the last target zone’s edge. The self-enhancement value of success and cost of failure was increased by framing the second round as a test of ability to perform under pressure.

While narcissism was not associated with overshooting, it was found to predict more target accuracy across both experimental conditions and it protected against the tendency to miss short in the performance pressure round. These results provide evidence that narcissism can be beneficial for motor performance. These results are also consistent with evidence that has found that narcissism is associated with approach motivation, which in turn may bring upon less undershooting.


Poster Session 1 Presentation 16 Austin Phillippe & Elizabeth Van Horn

Advisor: Dr. Lyons

Assessment of Cedar (Juniperus ashei) Removal on Native Grassland Re-establishment in the Texas Hill Country

Fire suppression coupled with increased grazing pressure has resulted in an increased abundance of Ashe’s Juniper (Juniperus ashei, a.k.a. “cedar”) in the Texas Hill Country. While native to Texas, J. ashei encroaches on natural savannas, creating dense monospecific stands called “cedar breaks.” In the understory of J. ashei only a handful of species can persist and in limited biomass. With the aim of increasing native grassland diversity, J. ashei has become the focus of an intense removal campaign throughout this region; however, with its removal the cleared areas are susceptible to establishment and spread of the non-indigenous, invasive C4 grass Bothriochloa ischaemum (King Ranch (or KR) bluestem. Thus, where management of J. ashei is anticipated to increase productivity of valued native forage grasses, its removal often results in establishment and spread of B. ischaemum.

This study is designed to provide guidance to land managers on the most effective approach to native grass restoration following J. ashei removal. Throughout the U.S. Great Plains direct seed sowing is the most widespread method for grassland restoration. Nonetheless, restoration ecologists in south Texas report mixed results with direct sowing, presumably due to high variability in rainfall that characterizes the region. Based on results from previous studies, we hypothesize that 1. grassland restoration will be more successful in areas where J. ashei is removed, 2. early successional species will have higher rates of establishment, and 3. establishment by plug will be more effective than direct seed sowing.

Summer 2014 research has focused on preparation for the manipulative field study that will be conducted fall 2014. Three indigenous species of rangeland and conservation concern will be seeded or plug planted in a fully factorial experimental design. The species include: Sorghastrum nutans (yellow Indiangrass), Schizachyrium scoparium (little bluestem), and Bouteloua curtipendula (sideoats grama). Summer research has focused on identifying suitable sites, developing an experimental design, and conducting a study on cold stratification of seeds to improve germination rates.

For the field study, seeds and plugs of three focal native species will be established in a 3 x 2 fully factorial experiment in using species (3) and establishment method (seed or plug) as factors. We hypothesize that plug planting will yield higher rates of establishment than direct seeding, but will vary among species and sites. We also anticipate that post-removal clearing method, land use history, and soil composition will be determinants of species establishment. Through careful site selection, efforts will be made to minimize these factors. For the cold stratification study, seeds of seven native grass species were subjected to sub-freezing temperatures for 0, 1, 2, or 3 weeks. Seeds were then germinated in either sterile petri dishes or potting soil using a randomized complete block design. Results of the stratification study will be reported. Funding Source: Texas Ecolab

Poster Session 1 Presentation 17 Sophie Wardle Advisor: Dr. Murphy

The Effect of Perceived Social Competition on Corticosterone Levels in the American Goldfinch

Many studies have shown that corticosterone levels rise as a result of various stressors such as heat, handling, and withholding food and water; however, few studies have drawn ties between corticosterone levels and social stressors. For my project, I will test the question of whether lack of access to food that directly arises as a result of competitive interaction increases stress in the American Goldfinch (Carduelis tristis). We hypothesize that birds mobilize corticosterone when social competition is perceived. In order to test this, male goldfinches will be exposed to 3 different conditions for 2 hours each, with blood being drawn first as a baseline as well as after each condition. For the different conditions, two variables will be manipulated: the presence of another male (competitor) and the presence of resources (food) in a cage that is visible but not accessible to the focal male. We predict that birds will have the highest level of plasma corticosterone after being exposed to a stimulus bird that has access to food, while the focal bird does not, simulating the loss of resources to a competitor. Data collection is underway, and the corticosterone levels experienced by each individual in the three conditions will be compared within birds in a paired-test fashion. We expect that birds will have higher stress response when they perceive that their lack of access to resources is due to a lost competitive interaction.


Poster Session 1 Presentation 18 Jonathan Zeitzer Advisor: Dr. Shinkle

The Effects of UV Radiation on Kale Growth in a Hydroponic System

Through a collaboration with Local Sprout, a Trinity-alumnus-owned hydroponic farm, we are investigating the effect of adding UVB radiation to the light environment for kale plants grown under blue and red light emitting diodes producing no UV radiation. We used a single Q-Panel UVB 313 48 inch bulb wrapped with 2 layers of cellulose acetate as the UVB source. The lamp provided approximately 200 mW m-2 of UV radiation at 10 cm with a center wavelength off 313 nm. Radiation was measured with a UVP UX-97651-10 meter. Plants were irradiated for 1 h per day. Both control and experimental plants were grown under a 12/12 light dark cycle and the UV treated plants received supplemental radiation in the middle of the light period. To obtain dose-response information, plants were placed at several distances from the light source. Leaf chlorophyll and a general measure of flavonoids (UV absorbing pigments) were measured at 1-2 day intervals with a ForceA fluorescence spectrometer. At weekly intervals leaf tissue was harvested. Samples of 10 -20 mg were extracted in methanol 1% HCl for 48 h at -20o C and absorption spectra taken to characterize UV absorbing pigments present. Samples of 100 mg were extracted by freezing in liquid N2, and homogenizing in aqueous buffer. These extracts were then reacted with N,N-Dimethyl-p-phenylenediamine dihydrochloride as a measure of antioxidant content. The compound (±)-6-Hydroxy-2,5,7,8-tetramethylchromane-2-carboxylic acid (Trolox) was used as a standard. Preliminary data indicates a UVB dose- and time-dependent increase in general flavonoids, UV pigments with specific absorption maxima and Trolox equivalence units. Both biochemical and commercial implications will be discussed.

Funding Source: Trinity BSURF and Trinity Entrepreneurship program

Poster Session 1 Presentation 19 Jogen Atone Advisor: Dr. Roberts

Investigating the Mechanism for ApoE Secretion by Astrocytes

Astrocytes are supporter cells in our brain that aid neurons by synthesizing and secreting various neurotropic factors as well as integral cellular components like cholesterol and lipids wrapped in apolipoproteins. Apolipoprotein E in particular is commonly used in astrocytes as the primary intracellular transporter protein, and has been shown to play a pivotal role in the development of Alzheimer’s disease, though the mechanism that regulates astrocytic Apo E synthesis and exocytosis is still unclear. Some studies suggest the role of 24(s)-hydroxylase, a sterol biosynthetic enzyme, in the synthesis and transportation of ApoE by astrocytes as 24(s)-hydroxylase signifies the hydroxylation and the consequent emission of solubilized cholesterol into CSF. Our lab in particular has focused on the amplifying effect of estradiol on the Apo E production by astrocytes, and has also shown that as astrocytes age, Apo E production decreases; however, the mechanism that accompanies the rise (or fall) in Apo E is has not been shown.

MAPK (mitogen-activated protein kinase) pathway is a common pathway for various cellular functions that governs cell proliferation, differentiation, and apoptosis among other functions. Estradiol has been shown to activate multitude of signaling pathways in mammalian cells including MAPK pathway, and as such estradiol may be influencing the Apo E increase as a necessary byproduct of astrocytic proliferation rather than as a direct signaling molecule for Apo E production. In this experiment, 17M astrocytes were treated with 2-MeSADP, a known substrate that binds to purinergic receptors associated with MAPK and cell proliferation to see if Apo E is increased as with estradiol treatment. Furthermore, neurons grown in combinatorial conditions including with astrocytes, estradiol treatment, and oxidative stress (H2O2) were stained for Apo E and were imaged using Nikon confocal microscopy. Though the results are not yet conclusive, 2-MeSADP has so far resulted in a slight increase in Apo E.

Funding Source: Kline Fellowship

Poster Session 2 Presentation 20 Hanna Batory & Amanda Nguyen

Advisor: Dr. Roberts

The Effect of Modulating Neuronal Membrane Toxicity of Beta Amyloid

Alzheimer’s disease (AD) is the slow and progressive development of memory impairment and cognitive deficiencies caused by an increase in beta amyloid (Aß) plaques. Distribution of cholesterol throughout the cell membrane affects the site and the attachment of beta amyloid, leading to its aggregation on the cell membrane and cell apoptosis. For this experiment, HT22 cells, which are mouse hippocampal neurons, were used to represent a close model to Alzheimer’s development. These cell cultures were be tested with Methyl ß Cyclodextrin (MßCD), which was used to extract cholesterol from the plasma membrane of the cell, and ß-Amyloid(1-40) to determine how varying levels of cholesterol affect the vulnerability of the cells and their response to Aß. It was expected that results will indicate as the cholesterol content decreases, the aggregation of ß-Amyloid plaques will increase and the cell will eventually undergo apoptosis, which would further the understanding of Alzheimer’s developmental onset. Keywords: Alzheimer’s disease, beta amyloid, cholesterol, neuron


Poster Session 2 Presentation 21 Greg Bustamante Advisor: Dr. Nguyen

Simulation of Particle and Fluid Flow Around Choanoflagellates Using the Method of Regularized Stokeslets

Choanoflagellates are unicellular organisms whose intriguing morphology includes a set of collars/microvilli emanating from the cell body, surrounding the beating flagellum. Certain species of choanoflagellates are also known to attach themselves to a substrate via a pedicel which extends from the cell body. We investigate the role of the microvilli and pedicel in the feeding behavior of the organism using the method of regularized Stokeslets and the method of images for regularized Stokeslets. These models allow us to depict the effective capture of nutritional particles and bacteria in the fluid as well as analyze the flow field around the choanoflagellates.

Funding Source: Trinity University Murchison SURF Award

Poster Session 2 Presentation 22 Imon Ferguson & Hamilton Rogers

Advisors: Dr. Spiegel & Dr. Healy

Measuring the Effect of Biomixing with Forced Rayleigh Scattering

In many systems, particularly on a microscopic scale, motion cannot be predicted by linear kinematics. In such cases, diffusive motion provides a more accurate depiction of mass transport. This holds true when introducing living and swimming organisms into a particular medium containing already diffusive particles, as such organisms leave behind a wake that provides a “biomixing” effect. Using an apparatus that employs the method of Forced Rayleigh Scattering, the molecular decay diffusion coefficient of isomerized photoexcited cis-state methyl-orange molecules are measured in samples of basic water and in samples of basic water and a medium containing motile bacteria. By varying the “pump” angle, we show a linear increase in the diffusion coefficient of the samples of just methyl orange and water, while an unrecognizable increase in the diffusion coefficient of the sample containing the motile bacteria is observed. In addition, varying the concentration of bacteria in a sample upward generally results in higher diffusion coefficients at a single pump angle. We show that as expected, the presence of increased concentrations of bacteria, both motile and non-motile, in our samples results in increased diffusion coefficients for the methyl-orange tracers.


Poster Session 2 Presentation 23 Clay Ford Advisor: Dr. Lehrmann

Sedimentology and depositional environments of the transition interval between the non-microbial bearing

strata and large microbial reefs in the Cambrian Wilberns Fm., Mason County, TX

With the discovery of oil fields in pre-salt strata of offshore Brazil, interest in lacustrine microbialites has greatly increased. Marine microbial carbonates contain similar grain types, textures and microbial structures that allow them to serve as powerful analogues for the heterogeneity of pre-salt microbial hydrocarbon reservoirs. Private ranches of have made accessible Upper Cambrian microbial mound and reef complexes along the Llano River allowing for the detailed study of microbialites at various outcrops.

The aim of the study is to better understand factors that led to the origin and growth of large microbial reef mounds and the processes that deformed the underlying and adjacent strata. Sections were measured, photographed, sampled and spectral gamma ray measurements were taken of the strata immediately beneath and adjacent to microbial reefs at two localities. Observations of texture, graintypes, and sedimentary structures were made in outcrop, polished rock slabs, and thin sections to interpret environments immediately preceding and during microbial mound growth.

Facies types include skeletal lime grainstone, heterolithic (sandy/silty limestone), intraclastic “flat pebble” conglomerate, and oolite beneath the microbial mounds and microbial intraclastic breccias adjacent to the mounds.

Skeletal lime grainstone is interpreted to represent shallow subtidal open marine environments on the basis of grainy texture and stenohaline fauna of echinoderms, trilobites, and brachiopods. Oolite grainstone is also interpreted to represent high energy, open marine shallow, subtidal environments on the basis of asymmetric megaripples, and included stenohaline fauna. Ooids form as abiotic precipitates in current agitated, tropical carbonate saturated waters. Flat pebble conglomerates are interpreted to represent storm events on the basis of channel geometries, scoured bases and rounded clasts. Heterolithic facie is interpreted to represent low-energy tidal flat deposition on the basis of fine grain size, reversing current indicators, tidal bundling, and mud cracks indicating desiccation.

Spectral gamma ray logs reveal strong cyclicity and an upward decrease in siliciclastic content approaching the microbial mounds. Facies patterns and gamma ray signature show an excellent correlation between sections.

Funding Source: Shell, Chevron, ConocoPhillips, Statoil

Poster Session 2 Presentation 24 Sara Guarino Advisor: Dr. Hill

Developmental Changes in Activity Levels for a Killer Whale Calf and Her Mother Across Three Years of Life

Currently, little is known about how killer whale calves regulate their resting opportunities as they become more independent from their mothers. The current study explored the resting behaviors of a killer whale mother-calf pair in human care during the first 3 years of life. Archived videos (5- 15 minutes) were collected during daytime from birth to 36 months at 6 month intervals. Changes in duration and speed of mother-calf swims, independent swims, and swims with others were assessed across the 3-year period. The results indicated that the calf displayed few resting behaviors across the observed months. During the first year and a half, the calf swam with her mother most often in a faster-paced swim, but was less likely to engage in this swim by the 2nd year. Additionally, during the 3-year period, the calf did not exhibit very active swims when with her mother. The findings suggested that, across the observed period, the calf rested while circuit swimming with her mother at a slow pace. Furthermore, by the 3rd year, the calf preferred to engage in more alert activities, not including her mother. Additional research is necessary to better understand the mechanisms of rest for developing calves.

Funding Source: St. Mary’s University Summer Undergraduate Research Fellowship

Poster Session 2 Presentation 25 Jessica Heppard Advisor: Dr. Murphy

Do Female Siamese Fighting Fish (Betta splendens) Modulate Their Investment in Aggression Depending on Resource Value?

The value an individual places on a resource may reveal the strength of either sexual or social selection acting upon a population. Social selection acts upon an individual’s ability to gain access to resources that are not directly mate based, and so acts on both males and females, while sexual selection focuses on competition for access to mates, and so is generally acting on males alone. Female Siamese fighting fish, otherwise known as betta fish (Betta splendens,) can be aggressive towards other females, particularly when first establishing a hierarchy that allows predictable access to resources. Female betta fish were presented with a novel female and different resources to compete for, either non mate-based (small food stimulus, large food stimulus), or mate-based (small male stimulus, large male stimulus). We monitored whether fighting was more frequent and more intense when a resource value was high. To do this, we measured the relative aggressive behavior of the females towards each other when faced with either a high-value or low-value resource. As another test, we compared the level of female aggression for a food resource against aggression over a mate resource, as this provides a proxy of relative strength of social (competition for food resource) versus sexual (competition for mate resource) selection acting upon female aggression. Data are currently being analyzed and we predict that females will incur greater risks of fighting when resources are high compared to when the resource value is low. Furthermore, we predict that females will show more aggression when competing for food compared to competing for a male.

Funding Source: BSURF

Poster Session 2 Presentation 26 Tyler Howard, Angel Bottera, & Audrey Hazelwood

Advisor: Dr. Childers

Children’s Visual Attention to Dynamic Events and Their Early Verb Learning

Children learning verbs must analyze dynamic scenes, and link verbs to specific elements and subevents within them. In this study, a Tobii x120 eye tracker recorded visual attention to specific aspects of events while children heard new verbs. This study examines how children process variation in tools and affected objects across events. Children aged 2;4 to 4;10 were presented with complex actions; actions were varied by changing the tools used to execute the actions, by changing the object affected by the action, or children saw a single event (control). At test, two actions were presented in a split-screen format; one side displayed the novel verb performed with a new tool and affected object, while the other side displayed a distract action. Children were asked to distinguish which event depicted the new verb through pointing to the side of the screen showing the candidate referent of the learned novel verb.

Results show that variation shifted children’s visual attention towards elements that changed across trials and away from those that stayed the same across trials. This is important because it provides indirect evidence that children are comparing one event to another. At test, importantly, children in the tool and affected object change conditions succeeded above what could be expected by chance, while children in the control group were less successful. As a whole these results show that children attend to variation and that it may be useful for verb learning.

Funding Sources: National Institutes of Health, Trinity University Murchison SURF Award, Trinity University

Poster Session 2 Presentation 27 Nathan King Advisor: Dr. Murphy

Group Size, Sociality, and Social Connectivity, and its Relationship to Foraging Success in the Black-crested

Titmouse (Baeolophus atricristatus) Foraging interactions are of great interest to behavioral ecologists, however little is known

about the relationship between individual variation and social structure as it relates to resource acquisition. We hypothesize that competition affects access to food resources and that both dominant birds and group-foragers benefit from early discovery of novel food. We predict that dominant birds (that are successful at monopolizing feeders), as well as larger family-groups (parents with their fledged young), or more social birds (greater network connectivity) will more quickly gain access to novel food sources, and will also have greater access to food. We studied the effect of changing the quantity and location of feeding resources on the foraging behavior of individuals and feeding groups of Black-crested Titmouse, Baeolophus atricristatus. To do this, we employed radio frequency identification technology (RFID) hooked up to 11 feeding stations placed in an array in the hill-country of Texas. Radio tags were attached to approximately 30 birds, and readers that were attached to seed-feeders recorded each time a tagged bird foraged from a feeder. Our experimental manipulation involved collecting 10 days of baseline data to establish the birds’ normal distribution and foraging rates. As a second step in the study, we removed all 11 feeders and placed a single feeder in the middle of the feeding array. Analyses are underway and we expect that dominant birds, birds in larger family groups, and birds with greater social ties will be better able to find this novel feeder, and will be more successful at maintaining access to this novel resource. Our study emphasizes the need to consider many aspects of individuals’ social interactions in models of social networks.


Poster Session 2 Presentation 28 Caroline Kuhn Advisor: Dr. Sperling

Ideology or Placating? Cognitive Load and Latinos’ Attributions for “the Gap”

An expansive body of literature has discussed the rather wide gap separating Latino and White students from kindergarten through graduate school (Thernstrom & Thernstrom, 2004). Although many of the alleged causes for the gap are structural in nature, some intrapsychic explanations, such as stereotype threat (Steele, 2010), have gained traction in the psychological community. The present study advances this theoretical perspective by exploring whether Latino students internalize self-defeating, culture-blaming attributions and suppress structure-blaming attributions for the Latino-White achievement gap. A total of 180 Latino college students drawn from two unique samples completed a questionnaire prompting them to make causal attributions for the differences in academic performance between Latino and White students. Whereas participants in the experimental condition were placed under cognitive load, participants in the control condition merely answered the items without interference. Results indicated that participants in the experimental condition were more likely than participants in the control condition to make structure-blaming attributions. Thus, it appears as though structure-blaming may be a default attribution style that is overridden with sufficient motivation to expend cognitive effort. Implications for promoting Latino college student success are discussed in the context of racial ideology theory and critical race theory.

Funding Source: St. Mary’s University Summer Undergraduate Research Fellowship

Poster Session 2 Presentation 29 Julianna Kurpis Advisor: Dr. Shinkle

Finding the UV Fingerprint Plants function in environments with small but biologically significant ultraviolet (UV)

radiation, yet the sensory systems used by plants that respond to UV radiation are not fully understood. Recently a photoreceptor responding to UV-B radiation, urv8, was discovered, but it appears to work only in mature plants and not seedlings. It may not be responsible for all responses to UV-B radiation even in white light grown plants. Another photoreceptor, phototropin, has also been implicated in responses to UV-B and UV-C in seedlings grown in the dark or in dim red light (DRL). One response present in DRL grown seedlings that occurs when irradiated by UVB and UVC is a change in the peaks and other structures in the absorption spectra for methanol extracted phenolic pigments. We tested the response of photoreceptor mutants to that of the wild type in Arabidopsis plants in different radiation treatments, focusing specifically on the UV-B and UV-C parts of the spectrum. We extracted pigments from normal, uvr-8 deficient and phot-1 deficient plants treated with white light alone, white light plus UVB, and white light plus UVC. We also extracted pigments from normal, uvr-8 deficient and phot-1 deficient seedlings grown in only red light conditions, red light plus UVB, and red light plus UVC. We are collecting data and optimizing experimental conditions to obtain a consistent shift in the spectra from pigment extracts. Once our baseline conditions (the UVB/UVC “fingerprint”) is established, we will evaluate the responses of uvr-8 deficient plants to UV-C light, and searching for a possible correlation between phot-1 deficient plants and UVC light.


Poster Session 2 Presentation 30 Gabriella Montemayor Advisor: Dr. Davis

Reducing Overpopulation by

Offering Low-Cost Health Services

Overpopulation of domestic animals in the United States is an epidemic that cannot be ignored. It can cause many problems in the community including, diseases, higher cost to the city, the danger and threat stray sick animals possess, and the moral strain caused from euthanizing so many adoptable pets. In this research, we looked into the effects of implementing low cost animal health services as a possible resolution to the overpopulation dilemma. Although implementing this particular solution does present drawbacks, mostly in the financial sector, it is very beneficial in helping reduce the amount of strays wandering the streets. By offering low cost health care services you are reducing the amount of animals being surrendered by owners, making the idea of becoming a pet owner more appealing while also allowing sick animals a chance at getting the proper medical attention. By implementing such systems and making the community aware of them, we can obtain this goal.


Poster Session 2 Presentation 31 Mary Moscosa Advisor: Dr. Yang

Disciplines as a Cultural Factor and Its Contribution to CEO Success or Failure

Disciplines can be understood as the practices that help a business grow. However, how they contribute to CEO success is an under-studied field. The aim of this project is to systematically examine such a relationship through literature review and case studies. Within this remit, we intend to address four research questions: (1) Why are disciplines considered a cultural element? (2) Why are disciplines required of CEOs’ success? (3) How have disciplines contributed to the success of the studied global managers? And (4) How have non-disciplinary behaviors failed the studied global managers? By answering these questions, we are able to identify relevant concepts and theories that explain the disciplines-performance relationship. We have also selected some typical cases for indepth comparison, including global managers Jeff Bezos, Mary Barra, Carlos Slim, and Guadalupe Castañeda. Our preliminary results reveal that disciplines as a culture element are different among these managers. In addition to explain how disciplines can be deep-rooted from a particular culture, we will also demonstrate how they can be a factor for both success and failure.


Poster Session 2 Presentation 32 Jamal Murray Advisor: Dr. Johnson

The Effects of Sexual Selection on the Copulatory Morphologies of Tropical Lizards

Sexual selection is a mode of natural selection that occurs when some individuals are more successful at obtaining mates than others. This can happen if males compete with each other for access to females (intrasexual selection), or if females are selective regarding with whom they choose to mate (intersexual selection). If the pressure to obtain mates varies among populations, the strength of sexual selection may also vary by population. Further, if certain traits lead to increased mating success, those traits will evolve differently among populations or species with differing sexual selection pressures. Male body size is a trait generally associated with intrasexual selection, as larger males can more successfully compete against smaller males. Thus, sexual size dimorphism, the difference between male and female body size, is a good measure of the strength of intrasexual selection in a species. In this study, I am investigating six species of Anolis lizards that occur in the same ("trunk-crown") microhabitat and have convergently evolved to be morphologically and ecologically similar, but that differ dramatically in their sexual size dimorphism. I am measuring the effects of sexual selection on copulatory morphologies, including the testes, kidneys, and the hemipenes and the muscles that move them, because each of these structures has an important role in male copulation behavior. I predict that, regardless of the frequency of copulation behavior exhibited by a species, the species that experience stronger selection will have larger copulatory structures.


Poster Session 2 Presentation 33 Sarah Pickett Advisor: Dr. Shinkle

Relevance of short wavelength UVB radiation to regulation of plant growth in natural light environments

It has been shown that in laboratory conditions plants respond specifically to shortwave UV-B (280-300 nm). This study investigated the effects of shortwave UV-B on plants in a natural light environment. Atmospheric ozone levels are known to influence shortwave UV-B, specifically from 290-300 nm. Tropospheric ozone, which is a component of smog, also blocks shortwave UV-B. To explore this variable, we are using both rural and urban test sites to see if there is a difference between the two. Once sites were characterized, we set up test plots where native Texas grasses were treated either with 1) short wavelength UV-B excluded (sunlight filtered by 0.13 mm cellulose acetate) or 2) all UV-B reaching the grass (sunlight filtered by Aclar™). A Spectroradiometer was used to obtain solar spectra at the various test sites. Native Texas grasses, sideoats grama (Bouteloua curtipendula) and silver bluestem (Bothriochloa laguroides), were used for field tests. The field tests take place for ten days before reflectance and absorbance data are taken to determine the effects of the different treatments. Reflectance data is obtained with a reflectance spectrometer. For absorbance data, grass blade segments are placed in methanol 1 % HCl and absorbance spectra of extracts are taken. In addition to field tests, UV supplementation tests in which sideoats grama received supplemental UV treatments were conducted. In the greenhouse tests, there was a control group, a group that received the full UV spectrum, and a group that received all but the shortwave UV-B. The UV treatments were 1.6 kJ per square meter per day for full spectrum UV-B and 3.0 kJ per square meter per day for long wavelength. Reflectance, absorbance, and flavonoid/chlorophyll measurements were taken at various times throughout the trials. So far the results suggest that shortwave UV-B causes changes to reflectance properties of silver bluestem and changes to absorbance properties in silver bluestem.


Poster Session 2 Presentation 34 Yanjiao Qin Advisor: Dr. Lehrmann

The Triassic marine reptile Keichousaurus hui of western Guizhou Province, China: sexual dimorphism and environmental

conditions leading to exquisite fossil preservation Keichousaurus hui was discovered in 1958 by Yang Zhongjian. It was the first

Triassic Marine reptile to be found in Asia. Keichousaurus hui is a small sauropterygian reptile typically no longer than 20 cm long. Previous studies have shown that Keichousaurus hui is viviparous as pregnant female individuals have been fossilized with embryos inside.

This study conducted a morphometric analysis of 49 specimens to determine the differences in 23 morphologic traits developed during ontogeny (development from juvenile to adult) and in sexual dimorphism (male vs. female). The results demonstrate that allometric growth of Keichousaurus hui can be seen in its skull, eyes, neck and other attributes. The ontogeny of Keichousaurus hui can be divided into infancy, adolescence and three adult stages. Sexual dimorphism is represented primarily by differences between appendages relating to reproductive behavior. The female humerus and femur are nearly equal in size, whereas, the male’s humerus is generally longer the femur. The expansion of the distal end of the humerus is more pronounced in male individuals. The proximal end of ulna is obviously expanded in the male also. The length of the forelimbs is consistently greater in the male than in the female. Although the morphology of Keichousaurus hui indicates primarily marine life environments, attributes of the appendages indicate these reptiles had the ability to go ashore.

Keichousaurus hui is found in local deposits of platy bedded, laminated black shale and marl within the Late Triassic, Carnian Zhuganpo Formation of southwest Guizhou. The lack of benthic fauna, lamination and black color of the fossil deposits suggests deposition within a semi enclosed, restricted, anoxic sea developed following drowning of the Yangtze Platform and during the retreat of the last vestiges of the Nanpanjiang seas from western Guizhou. Geochemical analysis reveals elevated levels of elements indicative of reducing conditions and high nutrient concentrations such as U, Mo, V, Ba, P, and Ni, as well as high TOC content in comparison with areas of the Zhuganpo Formation that are barren of fossils. Elevated nutrient flux from a nearshore source, coupled with stagnant water circulation led to anoxic bottom waters resulting in the exquisite fossil preservation.

Funding Source: Shell International Exploration and Production, Saudi Aramco

Poster Session 2 Presentation 35 Kelly Seeber Advisor: Dr. McIntyre

Development and Validation of a Social Desperation Inventory

We developed a brief (8-item) scale to measure social desperation, which describes the urgent need of some individuals to form new social relationships, as well as their overdependence on the few relationships they may already possess. In Study 1, we developed a pool of 37 potential items based on prior theorizing, and then examined the psychometric properties of these items. Based on exploratory factor analysis and reliability results, we retained eight items in our final Social Desperation Inventory (SDI). Studies 2-4 established the construct validity of the SDI. Study 2 found that the SDI correlates positively with measures of belongingness needs and loneliness. Study 3 found that the SDI correlates negatively with measures of self-esteem and happiness. Study 4 found the SDI correlates positively with measures of depression, social anxiety, and avoidance motivation. Overall, the psychometric properties of the SDI support its use in future research.

Funding Source: Trinity University Murchison SURF Award

Poster Session 2 Presentation 36 Jake Stercula Advisor: Dr. Johnson

Body Temperature and Brain Lipid Composition in Puerto Rican Anole Lizards

An important component of communication between neurons in the brain occurs when axons, cellular structures that reach out from the cell body to neighboring neurons, transmit electrical signals. These electrical signals travel faster when the axon is insulated by a myelin sheath, which is composed mostly of lipids. Body temperature influences the type and concentration of lipids within the brain. Therefore, understanding how temperature affects brain lipids may allow better insight into how temperature affects neural communication and behavior across species. Puerto Rican lizards in the genus Anolis comprise a natural experiment in the relationship between temperature and brain lipid composition. These lizards have divided their arboreal microhabitats by climatic factors, with some species living in sunny, open areas, and others living in cool, deep shade of the forest. In this study, I compared three groups of species that have similar ecology, morphology, and behaviors, but live in different microclimates, and thus experience different temperatures. For example, A. gundlachi and A. cristatellus both occupy the "trunk-ground" niche. However, A. gundlachi (average body temperature = 25°C) tend to perch at higher elevations under the forest canopy while A. cristatellus (29°C) prefer sunnier perches at lower altitudes. Similarly, A. evermanni (27°C) and A. stratulus (30°C) occupy the "trunk-crown" niche, and A. krugi (28°C), A. pulchellus (30°C), and A. poncensis (34°C) all occupy the "grass-bush" niche. I measured the body and perch temperatures of 40 males for each species and obtained measures of snout-vent length and mass for each individual. After collecting these data, we collected flash-frozen brain tissues from 20 adult males of each species. I will use these brain tissues to identify and quantify specific lipids in the brain in these species using mass spectrometry or HPLC. I predict that body temperature will be the primary factor driving differences in brain lipid composition among species, regardless of the species' niche or evolutionary relationships.


Poster Session 2 Presentation 37 Ashley Tessnow & Tess Macapinlac

Advisors: Dr. Ribble, Dr. Hasfura, & Dr. Elaydi

Utilizing Regional Growth Rates to Model Mammalian Species Distribution

Species distribution models (SDM’s) serve as tools for predicting the geographic presence of a species based on previous observations and environmental conditions. Popular SDM’s such as GARP rely on a series of correlations in order to predict the presence of a species. In this study, we utilize growth rate approximations calculated with the Ricker model using ~100 years of historical distribution data from four species of field mice (Peromyscus) along with existing environmental parameters (temperature, precipitation, elevation). Our models predict the historical distribution of four species of mice with approximately 80% accuracy. We compare our models to commonly used SDM’s (e.g. GARP) and discuss how our models are useful in understanding the impacts of global climate change on mammalian species distributions.

Funding Source: NSF UBM

Poster Session 2 Presentation 38 Alejandra Trigoso Advisor: Prof. Goeckler

Medieval Enameling Techniques: Research, Re-Creation & Studio Application

For this project we have set out to research and recreate medieval methods of enameling on metalwork. Vitreous enamel can be described as powdered glass fused to metal by means of firing at high heat. Our research includes examination and comparison of medieval and pre-medieval treatises on metalworking and enameling with the goal of recreating the original enamel recipes and techniques in a modern setting. Gaining experience with certain enameling techniques used both in medieval and modern times, such as cloisonné enameling, champlevé and plique-a-jour enameling is also an objective. Aside from traditional research methods, this project has also involved a trip to New York City to take an enameling workshop and to view the enamel collections of the Metropolitan Museum of Art, The Cloisters Museum of Art and the Morgan Library collection. The findings from this course will serve as preparation for The Making and Meaning of Medieval Metalwork, a dual art and art history course taught in Spring 2015 by Professors Holly Goeckler and Douglas Brine.


General Session A Presentation 39 Douglas Steinman & Josh Humphreys

Advisor: Dr. Olofsson

On the probability of the development of Bateson-Dobzhansky-Muller incompatibilities that incorporates protein interaction

networks An important aspect of evolution is the process and mechanism of speciation. The

Bateson-Dobzhansky-Muller incompatibility (BDMI) model describes how fixed mutations in two populations can accumulate gene incompatibilities that result in reproductive isolation, and therefore speciation under the biological speciation concept, without the mutations causing lowered fitness within either population.

Orr’s model provides the probability of speciation based on BDMIs as a function of the number of mutations. This model, however, assumes that all genes interact with all other genes with a uniform probability of mutation. In short, a more integral gene may mutate as successfully as a less integral gene, which is highly improbable. We have been working on a new mathematical model in which the mutational rate of a specific gene is viewed inversely to its connectivity. This summer we have been testing the accuracy of this equation using genome databases of Saccharomyces cerevisae (yeast) due to the completeness of the data set.


General Session A Presentation 40 Dallas Akins Advisor: Dr. Hough

Superluminal Speeds in Helical Quasar Jets

Quasars are the most powerful galaxies in the universe. As matter falls toward the central supermassive black hole in a quasar, gravitational energy is converted into thermal energy in a compact, hot accretion disk. Near the inner part of the disk, some energized matter can be accelerated outward near the speed of light, collimating into relativistic jets spanning millions of light years. The angle between the jet’s trajectory and our line of sight has a large effect on the appearance of the jet in the sky. Using observations from the Very Long Baseline Array at a frequency of 15 GHz, we have analyzed the structures that make up the jet near the inner core region of the quasar 3C207. We observe 3C207 to be 6.3 billion light-years away; due to cosmic expansion our quasar is now located more than 8 billion light-years from Earth! We conclude that the jet’s 3D trajectory is not straight past ~0.3 milli-arcseconds (7 light-years) from its base. Our data suggest that the jet begins to spiral around a conical helix with an opening angle of ~2 degrees. Other observations at lower frequencies show that the jet eventually moves along a straight path farther downstream as the helix unwinds.

The jet is made up of plasma components traveling at a true speed of 0.996c (where c is the speed of light), which corresponds to a Lorentz factor of 11.2; however, we see individual components moving at apparent speeds varying from 7.6c to 10.5c. These apparent faster-than-light, or “superluminal,” speeds are merely an illusion due to relativistic motion at small angles to our line of sight. The observed range of superluminal speeds points to plasma components for 3C207 being ejected at different angles to our line of sight, ranging from ~2 to ~9 degrees. One possible interpretation of the jet kinematics in 3C207 is that the components are constrained to follow an unwinding conical helical magnetic field whose axis is changing direction due to jet precession in a binary black hole system. Funding Source: Trinity University Department of Physics & Astronomy

General Session A Presentation 41 Duncan Frasch Advisor: Dr. Spiegel

Measuring diffusion of methyl red in polar solvents using forced Rayleigh scattering

In this experiment, we measured and compared the diffusion of the dye molecule methyl red in various combinations of polar solvents. To obtain the diffusion rate, we used a method called forced Rayleigh scattering. FRS uses the long-lived excited states of methyl red created from a “pump” laser in order to form a transient diffraction grating for a “probe” laser. The experiment measures the diffracted light which forms a decaying signal whenever the pump is turned off. This decay is due to the excited methyl red diffusing into the solution.

Binary combinations of polar solvents with dissolved methyl red were tested under constant pump incidence. Acetone, acetonitrile, dimethyl sulfoxide, and basic water were used as the solvents. We generated curves that compared decay rate versus the mole fraction of one of the two solvents. These tests showed that for many solvents, the diffusion rate in any balance of two solvents was in between the rates in each of the pure solvents, which is predicted by free-volume theory. However, this is not true for all of the solvents.

Solutions that contained water and any one of the other solvents exhibited different behavior from free-volume theory. A minimum diffusion rate exists at some mole fraction between the pure solvents. Our explanation is that methyl red is fairly hydrophobic, making water the poorer solvent. This leads to a first solvation shell of the other solvent that is hydrophobic inside and hydrophilic outside. A secondary solvation shell of water forming around the other solvent causes the diffusion rate of the methyl red to slow down even more, with a minimum at a certain balance of the two solvents.


General Session A Presentation 42 Benjamin Gomez & Andrea Lee

Advisor: Dr. Martinez

Modern Snail: Starting a Student Start-Up Our team recognized that it has become increasingly difficult for our generation to communicate with past generations who are not as technologically savvy. Additionally, in recent generations, personal greetings and birthday messages are often communicated via the internet, rather than through traditional snail mail. Living in our fast-paced and technologically driven society, we often do not feel we have enough time to compose and hand mail cards. After performing market research on the concept, our team has created an online, automated mailing service to assist people in sending personalized greeting cards. The website holds a database for each user in which the customer can create a profile that stores addresses of friends and family, along with birthdays and significant dates in order to send out cards automatically. Different from the competition, we provide our customers with eco-friendly cards designed by artists in our community. We are also able to adapt to the customers desired quantity of cards to send, allowing companies to customize multiple cards at a time. Over the course of the summer, our team had the opportunity to intern at Café Commerce, which is the new entrepreneurial hub located in the downtown library. The program is part of Mayor Castro’s SA2020 plan to support small businesses and stimulate entrepreneurial growth in San Antonio. As interns, we assisted in the formation of Café Commerce and worked directly with community members in various business sectors. We will continue to work as interns throughout the school year. Funding Source: Trinity University Stumberg Seed Prize, Trinity University's F.W. Olin Fund, Accion Texas, Image Freedom, and Trinity's Center for Innovation and Entrepreneurship.

General Session A Presentation 43 Michelle Oberndorf Advisor: Dr. Johnson

How Do Lizards Communicate? Static and Dynamic Visual Displays in Crested Anoles

Many animals use visual displays to signal messages such as the threat of aggression

or the intention to mate. Anole lizards serve as an excellent model for studying visual signaling, as males (and in some species, females) possess a brightly colored dewlap, an extendable flap of skin under the lizard's neck. This is an example of a dynamic signal, in which the lizard makes the display visible in response to the presence of a potential mate, competitor, predator, or prey. However, some species of anoles also possess a tail crest, composed of extended scales attached to the lizard's tail. Because this crest cannot be retracted, it is therefore visible at all times, and is an example of a static display. Males of two Puerto Rican species of anoles, Anolis cristatellus and A. gundlachi, both exhibit tail crests; however, the purpose of these crests is largely unknown. In this study, we tested whether dewlap size and crest size signal information about lizard body condition or bite force (an important component of fighting ability; measured by head shape). For 50 males of each species, we measured mass; body length; head width, height, and depth; dewlap area and length; and crest area, height, and length. We also took these measurements from 50 females of each species with the exclusion of the crest size, as females do not grow tail crests. Our preliminary analyses of male data suggest that in these lizards, tail crest size is correlated with body condition, but not dewlap size or head shape. This suggests that the static (crest) display may provide reliable information about the lizard's overall quality, while the dynamic (dewlap) display may be more strongly associated with an animal's immediate motivational state.


General Session A Presentation 44 Jacob M. Luber Advisor: Dr. Hibbs

Utilizing Machine Learning in Computational Biology and Classics

My research work involves utilizing support vector machines (SVMs) to solve biological and classical studies problems with complex input data by learning a model based on important patterns in trends from labeled examples, and then applying that model to determine the most likely label for new examples.

In one example, my work has focused on the reduction of postprandial blood glucose spikes through the development of an algorithm that predicts likely meal times from data gathered from a continuous glucose monitoring system (CGMS). Postprandial blood glucose spikes are troublesome for all individuals with Type 1 Insulin Dependent Diabetes Mellitus, and ongoing efforts by others are developing “artificial pancreas” technologies to administer insulin and glucagon automatically to mimic natural functions. However, current systems still require users to notify the system of meals and snacks, otherwise potentially dangerous glucose levels could occur. My algorithm addresses this shortcoming by utilizing a support vector machine learning model that will be coupled with elements from game theory to predict meals based on data available from CGMS. The initial result that the learning algorithm generates when run on weeklong blocks of data suggests that using the algorithm is significantly more successful than random in predicting meals because of how the derived feature set is generated. I intend to combine these results with a game theory algorithm to determine if a patient will gain utility by being prompted by their CGMS with a possible reminder to log a meal or snack. Similar learning techniques could also be used to to learn and model more complex information about how a user responds to insulin, and perhaps augment or replace insulin stacking algorithms.

In a second example, I utilized a similar methodology to predict which mouse genes are involved in osteoporosis by coding a learning algorithm that looks at expression levels of genes that are known to cause osteoporosis and attempts to generate features that when learned upon via a support vector machine approach are able to predict which previously unknown genes could potentially cause osteoporosis. From these results, mice will eventually be bred with these predicted genes knocked out in order to experimentally observe the computationally derived hypothesis.

Finally, as a third example, on an undergraduate research fellowship at the Harvard University Center for Hellenic Studies, I began work on a computational linguistics project that involves a new multi-textual translation of Iliad 12 and utilizes a machine learning approach via SVMs that seeks to improve optical character recognition of characters and ligatures in tenth century Byzantine Greek texts, manuscripts, and inscriptions. To generate features for the SVM learning algorithm, image processing techniques are applied to characters referenced in Harvard’s online database to distinguish between the ink which forms the characters and background noise such as hair follicles on the folio. From these processed images, “eigenletters” are found via singular value decomposition that represent important characteristics of a certain character or ligature. The most important of these “eigenletters” are turned into features for the classification algorithm to learn on in order to classify new characters or ligatures. This work has the ability to eventually facilitate the process of recognizing characters in historic manuscripts and inscriptions that are being translated. This could additionally help validate existing models of Homeric scholarship and provide insight into the relationship between the text and scholion hands in the Venetus A manuscript of the Iliad.

Funding Sources: Trinity University (Research Support and Research Stipend), Harvard University Center for Hellenic Studies (Research Support), Trustees of Harvard University (Research Stipend and Travel Expenses)

General Session A Presentation 45 Robert Hure & Samuel Simoneau

Advisor: Dr. Steele

Surface Plasmon Enhanced Fluorescence Using Gold Nanogratings

Surface Plasmon enhanced fluorescence was observed on gold gratings with a period of 500 nm. Gratings were manufactured with soft lithography using silicon master gratings and polydimethylsiloxane (PDMS) molds. Grating geometry was verified with Atomic Force Microscopy, which produces a topography scan of the gratings. Fluorescence from Rhodamine-B in the range of 550 to 700 nm was enhanced by up to a factor of 14 relative to a glass slide coated in Rhodamine-B using the same techniques used to coat the gold gratings. Fluorescent enhancement from the gold gratings corresponded to Surface Plasmons observed by measuring the transmission of white light through the gratings. White light transmission measurements were recorded while the incident angle was varied. Fluorescent measurements were recorded by fixing the angle of a 533 nm laser incident on the grating and varying the detector angle relative to the sample. Enhancing the fluorescence of two different molecules on the same grating with different lasers was attempted.

Funding Source: Trinity University Murchison SURF Award and Research Corporation Cottrell College Science Award

General Session B Presentation 46 Isaiah Ellis Advisor: Dr. Tarango

Hunting Buffalo in Oklahoma: Capitalism and Cultural

Representation in Indian Casinos

Casinos built on tribal lands have brought revenue, notoriety, and sometimes considerable political power to the tribes that own them. While their impacts on tribal and state economies and cultures are important and well-studied, my research project has paid more attention to the casinos’ aesthetic design. I traveled with my professor to twenty-three Indian casinos, big and small, belonging to seventeen different tribes in the state of Oklahoma, where Indian territories and tribal casinos are more numerous and visible than anywhere else in the United States. There, we observed and documented the interior and exterior aesthetics the casinos, paying special attention to features that evoke tribal history and culture as well as generic motifs that the average American might associate with ‘Indians’ – like tipis, eagle feathers, and buffalo. My presentation offers a typology of Indian casino aesthetics that illuminates broader issues of cultural representation and politics on tribal lands. Indian casinos illustrate the widely-used capitalist strategy to mold cultural images into a spectacle for consumers. Paradoxically, they also provide a platform for tribes in Oklahoma and elsewhere to assert their distinctness as a tribal culture and nation.


General Session B Presentation 47 Giovanna Espinoza Advisors: Dr. Urquijo-Ruiz

& Dr. Blanco-Cano

Empowerment of the U.S Latina: the Role of Higher Education in the Films Real Women Have Curves (2002)

and Mosquita y Mari (2012) Previous research has reported that U.S. minorities such as Latinos/as (more specifically

Mexican-Americans) have continuously struggled to demonstrate academic achievement. Due to the traditional gender expectations imposed on U.S. Latinas (girls and adults), academic success is even more difficult to attain for them. Through an interdisciplinary theoretical framework that encompasses film, ethnic, gender and cultural studies, this paper will examine visual representations of the role that education plays in the U.S. Latina community. In particular, this work will analyze how the films Real Women Have Curves (Patricia Cardoso, 2002)), and Mosquita y Mari (Aurora Guerrero, 2012) utilize educational aspirations as means of overcoming structural barriers within their own families, and U.S. mainstream society. In this sense both films provide examples of how a U.S. Latina can become empowered, aspiring to occupy more prominent professional positions, and reaching, at the same time, upward social mobility.


General Session B Presentation 48 Sonny Luna Advisor: Dr. Delgado

How students with learning differences respond to art education ADHD is one of the most commonly diagnosed and widely misunderstood disorders

in America. While “traditional” treatments are effective and widespread, alternative treatments for ADHD are often as effective as they are underused. In its current use, art therapy for ADHD students consists of selective and costly programs run by specialized, certified art therapists and implemented either as emotional therapy or as behavioral skills training. The work of these specialists is invaluable in assisting children with ADHD. However, their practices could be further utilized to serve students who struggle with verbal communication and literacy.

In this session, a review of art therapy programs serving students with ADHD both nationally and internationally will be presented. These programs will then be compared to the art experiences of students at a local private school for students with learning differences. Through observation, co-teaching, and interviews, I explored (1) how students with learning differences, ADHD in particular, perceive art classes and respond to artistic learning environments; (2) how teachers modify art lessons to meet the needs of students with learning differences; and (3) ways in which the class curriculum can be adjusted to model art therapy practices that more effectively engage students with learning differences. Preliminary findings addressing these research questions will be presented.


General Session B Presentation 49 Arnulfo Tunon Advisor: Dr. O’Connor

Assessment of peripheral immune parameters as non-invasive measure of VNS Efficacy: A Pilot Study

Vagal nerve stimulation (VNS) is an FDA approved treatment option for severe treatment refractory epilepsy and depression. However, short of full therapeutic effect, there are currently no biomarkers to measure VNS efficacy or to guide “dosing” decisions in an individual. Interestingly, VNS also has potent immunomodulatory activiaty via the cholinergic anti-inflammatory pathway, which inhibits peripheral immune response through acetylcholine-mediated reduction of proinflammatory cytokine production. Here, we utilized a whole blood immunoassay to determine whether the anti-inflammatory effects of VNS persist ex vivo and represent a novel biomarker for VNS efficacy. Lipopolysaccharide (LPS)-stimulated tumor necrosis factor (TNF)-α secretion was measured in whole blood collected from male Sprague-Dawley rats implanted with either active or sham VNS stimulator packs. In diluted whole blood collected prior to initiation of VNS, LPS-induced a significant and dose dependent increase in TNF-α secretion. Interestingly, LPS-induced TNFα secretion was rapidly decreased by VNS, and the blunted response persisted throughout the three week duration of the experiment. While, the repeated collection of blood was associated with an overall reduction in the total number of white blood cells in whole blood, no effect of VNS was observed. Additionally, VNS did not alter endogenous plasma TNFα levels, and differential WBC counts revealed that the anti-inflammatory phenotype of VNS-treated rats was not likely due to redistribution of lymphocyte/leukocyte populations. Together, these data suggest that the anti-inflammatory effects of VNS persist ex vivo and may provide a viable opportunity for developing a bioassay to rapidly determine VNS efficacy.

Funding Source: Cyberonics Inc. and Trinity University McNair Scholars Program

General Session B Presentation 50 Rosa Olivares Advisor: Dr. Stone

Fiesta Fundraising: Filling the Gaps of AIDS Service Organizations in San Antonio

Stigma has affected the way that HIV/AIDS in the United States has been funded since the beginning of the epidemic. Since the 1980’s AIDS service organizations (ASOs) have had to rely heavily on fundraising in order to provide needed services to those with HIV/AIDS and others at risk. This paper examines how ASOs in San Antonio, Texas are funded with attention to fundraising during Fiesta. This project analyzed government documents, newspaper articles, and archival documents, along with interviewing the directors of San Antonio ASOs and the CEO of the HIV Planning Council. The services that were funded the most and the least were identified. This paper argues that even thirty years after the start of the epidemic ASOs still have to rely on fundraising to provide critical services because stigma over HIV/AIDS persists.


General Session B Presentation 51 Jaferaly Hooda Advisor: Dr. Norman

The Culture Industry Online In his co-authored work Dialectic of Enlightenment, Theodore Adorno discusses a

concept referred to as the “culture industry.” This essay considers the impact of a capitalist base on the cultural aspects of the superstructure. Put more simply, Adorno explains the commodification of culture under capitalism. Walter Benjamin offers a different analysis in his essay “The Work of Art in the Age of Mechanical Reproduction” where he offers potential benefits brought about to art under capitalism, such as the democratization of the arts.

In this paper, I examine the ensuing discourse which took place between Adorno and Benjamin with respect to later thinkers who have updated the critical theory of the Culture Industry, then apply that theory to a contemporary setting. The debate between Adorno and Benjamin is reframed in a context which includes a number of factors the two could not foresee, particularly the internet as a tool for distribution of arts and digital technology providing a wider accessibility to them.


General Session B Presentation 52 Melissa Smallwood Advisor: Dr. Williams

Synaptic Troubleshooting: Making the Connection between Autism and Labor & Delivery Drugs

Autism Spectrum Disorder (ASD) is a pervasive neurodevelopmental disorder characterized by social deficits, difficulties in communication, and repetitive behavior. The recent increase in the rate of autism diagnosis in the United States – 1 in 68 children as of 2014 – has sparked interest within the research community to investigate potential causes and risk factors involved in the development of autism. Genetic and environmental factors – and interactions between them – have been implicated in the development of the autistic phenotype. It is believed that environmental stressors or toxins could modify the expression of important genes and proteins in brain development. Previous research assessing environmental factors related to autism indicates that a relationship may exist between autism and the labor-inducing drug, Pitocin, during childbirth. Therefore, the aim of this study was to determine if epidurals and/or labor-inducing drugs are potential risk factors for autism. Results from our population study show that children exposed to labor and delivery drugs during childbirth are 2.64 times more likely to develop an autistic phenotype (X2 = 3.88, p = 0.048). The data also show a relationship between duration of exposure and the chance of developing an autistic phenotype (X2 = 4.88, p = 0.027, OR = 2.64).

In order to assess the possible molecular effects of labor and delivery drugs, the expression patterns of six autism candidate genes - UBE3A, NLGN3, NLGN4, SHANK, CNTNAP2, and GABRB3, were assessed at various mouse developmental stages (Postnatal day 0, 7, 14, and 21). Indeed, altered gene expression was observed for all six target genes, with the most drastic changes occurring at postnatal day 0 and 7. The data suggest that exposure to labor and delivery drugs during childbirth could potentially interfere with normal expression of critical neurodevelopmental genes, such as those involved in synapse formation. Future behavioral studies are required to evaluate the long-term neurodevelopmental consequences of these drugs that could increase the risk for the development of autism.

Funding Source: Murchison Research Fellowship

General Session C Presentation 53 Nicholas Toffoletto Advisor: Dr. Ugolini

Reducing Charged Based Noise in Gravitational Wave Observatories

The gravitational-wave observatory LIGO uses optics suspended in vacuum. An ESD or electrostatic drive is a pattern of high voltage electrodes that controls the position of the optic. The high voltage redistributes charge on the optical surface mirroring the electrode pattern. Random charge motion in the dense regions of charge varies the electric field, changing the torque on the optic. The charging rate and surface conductivity (which is related to characteristic relaxation time) determine how long we can leave the system running without discharging the optic. Since we cannot change the substrate or remove the ESD, we look to reduce charge noise by investigating different cleaning techniques. For each cleaning technique we put a treated optic in vacuum at 10-4 torr, expose it to an ESD at 600 V, and measure the amplitude of the charge every two hours with Kelvin probe to determine the charging rate. Next we shut off the ESD to let the sample discharge and measure the rate. Both of these quantities are used to find how long it will take for the charge motion to exceed the noise limit for LIGO. We tested a variety of different techniques and cleaning solutions including First Contact, acetone, methanol, IPA and Liquinox. We found a two order-of-magnitude difference between the best and worst methods.

Funding Source: NSF Award #PHY-1068760

General Session C Presentation 55 Lizzie Hartson Advisor: Dr. Sullivan

Aspens, Monarchs, and Terraforming: Interdisciplinary Study of the Local and Global Perspectives in International Climate

Change Novels and Ecology.

This interdisciplinary project spans the genres of scientific nonfiction, science fiction, and climate change novels to explore local and global perspectives on climate change. Despite the current impact of climate change, there is no large-scale global intervention, and such an approach seems drastic and overwhelming. Science fiction, however, has a long history of speculating on global problems and possible solutions. The works we will be exploring are Margaret Atwood and Kim Stanley Robinson with their works Oryx and Crake and 2312, respectively. In terms of local approaches, Barbara Kingsolver narrates how Dellarobbia, an impoverished rural mother, is awakened to the global crisis due to a local anomaly in Flight Behavior. In order to supplement this literary discussion of the local, we also explore the scientific discussions of Sudden Aspen Death (SAD) impacting the High Lonesome Ranch in Colorado. The advantage of this interdisciplinary study is that it explores texts and issues on both the local and the global together, unlike most existing work focusing only on one or the other.


General Session C

Presentation 56

Ngoc-Tam Ngo Advisor: Dr. Yang

Personal cultures and their impact on Sino-US female CEOs’ success and/or failure to become global managers

Female chief executive officers (CEOs) are rare and extraordinary, and their studies are sporadic. This project intends to investigate how personal cultural behaviors impact on their success or failure to become global managers. Within this aim in mind, , we intend to address three research questions: (1) How female CEOs fare in the history and contemporary China and the US? (2) Why are personal cultural factors important to help CEOs become global managers? (3) How have their personal cultural behaviors attributed to their failure? By answering these questions, we are able to identify relevant concepts and theories that explain the personal cultures-performance relationship, establish Sino-US female CEO portfolios, and select typical cases for indepth comparison. Our preliminary findings show that female CEOs fare higher in China (51%) than in the US although this fact is reversed from the historical angle. They are mostly corporate founders of private enterprises, and have expanded their businesses in the US. Beside the entrepreneurial spirit, family businesses have made it easier for female CEOs to hold the executive positions. Moreover, having a female CEO increases the subsequent number of female executives in the company and vice versa. The most influential factor to the failure of female CEOs is that the expectations and norms around women’s responsibilities and roles within their households generate social, psychological pressure and undermines their confidence in achieving big goals.


General Session C Presentation 57 Mariah Wahl Advisor: Dr. Dupertuis

The Bible in the Final Novels of Philip K. Dick

This presentation examines the final three novels of Philip K. Dick, VALIS, The Divine Invasion, and The Transmigration of Timothy Archer, often referred to as the VALIS trilogy. Criticism of his work in general, and his late work especially, focus on religion, especially Gnosticism. But little attention has been given to Dick’s specific relationship to the Bible and scripture in these final texts. A careful definition of scripture reveals it gains most of its religious authority from its relationship to community, paradoxically maintaining a consistent religious tradition while shifting constantly to meet the needs of that community. Dick’s novels utilize this paradox by exploring scripture’s interaction with the communities of his novels, and highlighting the affect scripture has on the individual identities of his characters. Ultimately, in spite of the positive and negative effects scripture has on his characters, Dick makes no definitive evaluation of scripture. Instead, his novels suggest that the audience’s judgment of belief or non-belief is the defining value of any text, including Dick’s own work.


General Session C Presentation 58 Nicole Vreeland Advisor: Prof. Ward

Environmental Activism Through Art Activist artists strive to find a balance between artistic expression, and action for

change of systemic issues. This project pursues examples of artists who have achieved this balance in their art and to explain how they have gone about their successes. The environmental activist art movement began in the 1970’s with artists like Helen Mayer Harrison, Newton Harrison, and Robert Smithson. The contemporary artists chosen: Lillian Ball, Emily Bryant, and Patterson Clark are all working with plants; in particular they work to improve environments where invasive species are a concern. Invasive species are an environmental concern as populations are rapidly increasing worldwide, overtaking native habitats. In particular, the Mississippi River, largest river in North America, has many invasive species that pose a threat to the health of the river and even that of humans. This issue of invasive species of the Mississippi River is also explored in this paper and suggestions on how artists can tackle the problem.

Post research I was inspired and created my own environmental art. I worked with water lilies, which are an aquatic plant invasive in both Texas and the Mississippi River.


General Session D Presentation 59 Kelly Hewes Advisor: Dr. Phillips

Exploring the effects of exercise on cognitive dysfunction in the marmoset EAE model

Multiple sclerosis is a neuroimmunological disorder that affects the myelin sheaths that form around axons. This disease can be modeled in marmosets (Callithrix jacchus) both pathologically and behaviorally by injecting a peptide called myelin oligodendrocyte glycoprotein (MOG) to induce experimental autoimmune encephalomyelitis (EAE). We are particularly interested in how the progression of cognitive dysfunction in this model is affected by regular moderate exercise.

Cognitive dysfunction will be assessed in the form of changes in working memory throughout disease progression and will be tested using a radial arm maze. Additional assessments of structural and functional brain changes will be performed using resting state fMRI and diffusion tensor imaging (DTI).

Funding Source: Texas Biomedical Research Institute; Trinity University Murchison SURF Award

General Session D Presentation 60 Liam Fox Advisor: Dr. Mehta

Quantum few-body problems on a GPU The Schrödinger equation describing an N-particle quantum system is a partial

differential equation (PDE) in 3N dimensions. In general, the computational cost to solve PDEs increases exponentially with the number of dimensions. The usual method for solving the Schrödinger equation is to expand the solution as a sum of known "basis" functions with unknown coefficients, and reduce the PDE to a matrix eigenvalue equation for the vector of coefficients, which can then be solved on a computer. As it so happens, computer graphics also involve some heavy-duty matrix operations, so graphics cards (GPUs) have been designed specifically for this purpose. We used the recently developed CULA linear algebra library to explore the potential speed increases made possible by a GPU. Despite some of the computational overhead associated with parallelizing our code, we found that it offers a significant speed-up. We present some results for simple one-dimensional problems, and preliminary results for multi-particle systems using a gaussian basis set that explicitly incorporates two-particle correlations.


General Session D Presentation 61 Connor Morehead Advisor: Dr. Mehta

Quantum four-particle problem on a line We solve the Schrödinger equation for three-particle and four-particle systems

confined to move in one spatial dimension. We consider an “HHL” system of two heavy atoms and one light atom and an “HHHL” system of three heavy atoms and one light atom. Both systems are treated within the Born-Oppenheimer approximation with zero-range “contact” interactions. We present two “phase-diagrams” indicating the number of trimer and tetramer states and the signs of the atom-dimer and atom-trimer scattering lengths.


General Session D Presentation 62 Evan LeGros Advisor: Dr. Fogarty

Subsumption Data Strictures A data structure is a way to organize information within a computer. Different data

structures will speed up or slow down certain operations, and so are appropriate for different applications. For this project we consider the storage of sets: groups of unique elements. Two of the most basic data structures used in computer science are linked lists and binary search trees. In a linked list, each set is stored with a pointer to the next set in the list, forming a chain of data. Inserting sets into a linked list is easy: simply have the new element point to the front of the current list. However, searching a linked list is slow, and at worst must look at every element. In a tree each set is associated with two pointers: one to sets that are “greater” than it, and one to sets that are “smaller”. While inserting sets into a tree is slower than a linked list, searching a tree is much quicker, as we can often ignore entire chunks of the tree. For example, if we are searching through a thousand sets, rather than looking through all thousand sets in a linked list, in a tree we may only need to consider eight or nine.

In some applications, we define a notion of subsumption between sets: a relation that states one set is strictly more important than the other. For this project, we consider on-the-fly universality checking for finite state automata. With this application, we are only interested in minimal. One set is a subset of another when all the elements in the first occur in the second. A subsumption data structure keeps only the important sets: in this case the minimal subsets. When a new set is inserted into a subsumption data structure, we must also search for subsets or supersets already contained within the data structure.

The state of the art subsumption data structure is the linked list. As noted, searching in a linked list is very slow and, when using subsumption, every insert requires searching. However, the normal algorithms for searching a tree will not always find subsets or supersets. We design and implement a binary tree that supports subsumptive inserts. While a subsumptive insert requires looking at more elements than a normal insert in a tree, we are still able to ignore parts of the tree. To evaluate the efficiency of this data structure, we also implement a universality checker for finite state automata and a linked-list based subsumption data structure. We experimentally compare the list and tree-based data structures on random data of increasing size. We measure how frequently sets are compared, and how many memory locations are accessed. In this case study, trees make significantly fewer comparisons and memory accesses than linked lists. While not conclusive, our research suggests that tree-based subsumption data structures are more efficient than list-based structures. These encouraging results suggest development of data structures for more complex elements, such as ranked sets or graphs.


General Session D Presentation 63 Kristen Schultz & Ann Adams

Advisors: Dr. Lyons & Dr. Kwessi

Modeling the Competitive Dynamics Between Native and Invasive Grasses Under Varying Light Conditions

The C4 grass King Ranch (KR) bluestem (Bothriochloa ischaemum) was originally planted throughout much of Texas to restore degraded rangeland; however, the species has since become a full-fledged invasive pest for ranchers and private landowners. Widespread attempts have been made to reduce the species’ abundance including application of herbicides, mechanical removal and prescribed fire. Invasion theory suggests that species coexistence is enhanced through niche partitioning and that species with overlapping use for limiting resources (such as light availability) will be in competition. Here we use niche theory to assess the mechanism of competition between a native and non-indigenous grass at the seedling stage and the potential for restoration of native plant species as biocontrol to reduce KR bluestem establishment and spread.

We employ a two-way (8 x 2) factorial growth chamber experiment with species composition (8) and light condition (2) as factors. KR bluestem and two native grasses used widely in rangeland restoration, sideoats grama (Bouteloua curtipendula) and little bluestem (Schizachyrium scoparium), were grown from seed in 100:0, 50:50 or 0:100 ratios. Small pots (3.5 x 20 cm) were filled with hand-mixed soil that simulates the local environment and topped with Fafard Super Fine Germinating Mix. Once germinated and established, the seedlings were thinned to assigned species ratios, exposed to one of two light conditions (300 or 1000 μmoles) in Conviron growth chambers, model CMP 6050, and harvested every ten days over the course of six weeks.

When considering the likelihood of coexistence between two competitors, the niche difference (ND) and relative fitness difference (RFD) influence competitive dynamics. In order to quantify these measures, Carroll et al. (2011) use MacArthur’s Consumer-Resource Model to define ND and RFD as a function of sensitivity, or the proportional reduction in growth rate due to interspecific competition. In previous work done by Trinity undergraduate researcher Erin Tansey (Tansey et al. in review), we identified several theoretical and mathematical issues with the Carroll model. We made adjustments to the model to account for these limitations and aim to apply the modified model to our data. Our ultimate goal is to use this model to predict the future competitive dynamics between our focal native and invasive grasses under varying resource availability.

Carroll, I.T., B.J. Cardinale, and R.M. Nisbet. 2011. Niche and fitness differences relate the maintenance of diversity to ecosystem function. Ecology 92: 1157-1165.Tansey, E.,

Schultz, K., Afflerbach, C., Elaydi, S., Kwessi, E., Lyons, K.G. In review. From competition to facilitation: expanding on mechanistic models of species interactions. Ecology.


General Session D Presentation 64 Cassandra Watson & Katherine Walls

Advisors: Dr. Hasfura-Buenaga,

Dr. Balreira, & Dr. King

Modeling Epithelial cell Migration and the role of ZO-1 in Migration

Epithelial cell layers form cohesive monolayers with transepithelial electrical resistance. The tight junction closely seals the paracellular space and permits cell polarization. These distinct properties of epithelial cells are responsible for compartmentalization and vectorial transport of solutes. In the event of a wound, epithelial cell layers have an intrinsic program to grow together to seal the wound and re-establish the barrier. Our aim is to examine epithelial cell responses post-wounding using cells deficient in an important tight junction component, Zonula Occludens (ZO-1). ZO-1 is known to bind to the actin cytoskeleton as well as numerous other tight junction proteins. We are developing a mathematical model to understand the behavior of cell migration post-wounding. The model has two major components beginning with a diffusion term and transitioning into a linear transport function. Since the model accounts for the change in density as cells migrate, density measurements taken during migration are compared to the model. By understanding the differences in migrations with and without ZO-1, our goal is to quantify and explain the role ZO-1 has in epithelial cell migration.


General Session D Presentation 65 Austen Hall, Bryan Schrock, & William Garvie

Advisors: Dr. Brown & Dr. Fogarty

What is a Computation? Despite the prevalence of the term “computation” in both technical and everyday

language, what it actually means for a system to be computational remains a surprisingly vague and ill-defined concept. There is no accepted single definition of computation - many notions of computation exist within the literature, and they exhibit strikingly varied levels of inclusiveness. Donald Knuth’s notion of a computational method, for example, requires that a system satisfy a checklist of very specific features in order to count as a computational system. On the other end of the spectrum, notions known as pancomputationalist theories hold that every causal process in the universe is a computation. We take this variety of disparate notions to be indicative of a significant lack of clarity surrounding the term “computation”. This project addresses this lack of clarity by constructing a clearer understanding of what is required for a system to be computational.

We first formulate a well-defined, but restrictive, conception of computation from the ideas of Church, Turing, Knuth, and other computational theorists. This “canonical conception” holds that a computation must (1) compute a mathematical function, (2) be deterministic, (3) have discrete steps, (4) have digital inputs and outputs that (5) have a semantic interpretation, and (6) exist in order to solve a specific problem. We explore the limits of this conception through examples of systems that are commonly held to be computational but do not adhere to one or more of these requirements. We discuss which deviations from the canonical conception preserve computationality and which deviations (or combinations thereof) render a system non-computational.

Funding Source: Andrew W. Mellon Foundation and Trinity University

Chemistry Session A Presentation 66 Molly Hogsett Advisors: Dr. Mills

& Dr. Hunsicker-Wang

Synthesizing and Optimizing Chemical Modifiers for the Rieske Protein

Within the electron transport chain, the Rieske protein in complex III has a unique [2Fe-2S] cluster. This cluster becomes reduced upon oxidizing quinol, and further studies are being executed to understand how the reduction of the protein is coupled to H+ movement. Previous work has shown that the reaction of the Rieske protein from Thermus thermophilus with diethyl pyrocarbonate (DEPC) can result in modified and reduced protein. It is hypothesized that the DEPC-histidine adduct is electron deficient, resulting in an increase in the reduction potential that drives reduction of the protein. In this study, phenyl chloroformate, PCF, which has a similar structure to DEPC but with an attached phenyl ring, allows the addition of different electron withdrawing substituents. PCF does not change the CD spectra of Rieske as much as DEPC, but also in small enough quantities, it does not unfold the protein. On the phenyl ring, a nitro group has been added (creating nPCF) to change the electron withdrawing properties further. In small amounts both PCF and nPCF do not react appreciably with the protein. Addition of acetonitrile to aid in modifier solubility appears to increase reaction, but also results in unfolded protein. Further studies to optimize the conditions for PCF and nPCF reaction with protein are ongoing.

Funding Source: Robert A. Welch Foundation and NSF Award #1265545 & #1058273

Chemistry Session A Presentation 67 Chris Hertz Advisor:

Dr. Hunsicker-Wang

Probing the Role of the Amino Acids Adjacent to the Ligating Histidines of the [2Fe-2S] cluster of the Rieske Protein

The Rieske protein is an electron transport protein that contains a [2Fe-2S] cluster

which is ligated by two cysteines and two histidines. This ligation environment is affected by changes to other residues surrounding the cluster. The Thermus thermophilus Rieske protein contains a strictly conserved leucine adjacent to H134 and a smaller glycine residue proximal to H154 that is found in all respiratory Rieske proteins. To explore the role these residues play in the structure of the protein, two new mutants of the Rieske protein, G155L and L135G/G155L, have been created and are being characterized using UV-Visible and circular dichroism spectroscopies, chemical modification and X-ray crystallographic structural studies. G155L reacts differently with the chemical modifier diethyl pyrocarbonate, indicating that there may be a role for G155 in regulating histidine reactivity.


Chemistry Session B Presentation 68 Joshua Perkins Advisor: Dr. Mills & Meagan Coffer

Synthesis of the Precursors of benzannulated bis-cycloheptatrienide dianions

Antiaromaticity can be used to probe patterns of delocalization in ions with 4n π electrons. Current efforts are directed towards synthesizing coupled benzannulated cycloheptatrienide anions. Two different homo dimer dianons are currently being explored: bis-[3,4]benzocycloheptatrienide dianion (I) and bis[4,5]benzocycloheptatrienide dianion (II). Progress towards the synthesis of precursors to I and II is reported.

The synthesis of the [3,4] precursor I began with conversion of α-tetralone the ring expanded β-cycloheptanone. Coupling of the ketone to a diol followed by dehydration would give a benzannulated diene that will be halogenated and dehydrohalogenated to the dianion precursor

The synthesis of the precursor to the dianion of II, began with the synthesis of [4,5]benzocycloheptan-1-one which was α-brominated via the enol with N-bromosuccinimide. Subsequent dehalogenation using with 1,8-diazabicycloundec-7-ene resulted in the unsaturated ketone.

Approaches to coupling the ketones to the homodimers will be described.


I II

Chemistry Session B Presentation 69 Kelsey Kirkman & Rachel Tchen

Advisor: Dr. Mills

Characterization of the Antiaromaticity of Phenyl Substituted

Bis-Benzocycloheptatrienide Dianions

Antiaromatic compounds, which have 4nπ electrons according to Huckel's Rule, experience a delocalization of their electrons that leads to instability of the compound. To escape the instability, the unsubstituted compound localizes its electrons in the seven-membered ring system, so as to retain the aromatic benzene ring and separate the aromaticity from the antiaromaticty. A phenyl substitution on the benzene ring might persuade electrons to further delocalize, thereby increasing stability of the compound, which we can probe experimentally through proton shifts. This study seeks to elucidate the effect a phenyl substitution would have on the delocalization of the electrons, and thus the antiaromaticity. By synthesizing these antiaromatic compounds we can hope to better understand, characterize, and define antiaromaticity and thus, aromaticity.

The synthesis of 1-3 began with reduction to the ketone for different isomers of dihydroxynaphthalene followed by a triflate substitution and Suzuki cross-coupling to yield the phenyl substituted tetralone. This compound will then undergo a ring expansion, followed by a homo-coupling, bromination at the benzylic position, and dehydrohalogenation to yield the precursor compounds for 1-3.

Funding Source: NSF Award #1265545 and Robert A. Welch Foundation

Chemistry Session A Presentation 70 Elisabeth Purdy Advisor: Dr. Chandler

Selective Hydrogenation of Phenylacetylene Over Supported Gold Catalysts

Supported gold nanoparticle catalysts, while not highly active for hydrogenation reactions, are highly selective. The underlying support can have an important electronic influence on both the activity and the selectivity. In order to understand the electronic properties of various metal oxide supports and their effect on reaction kinetics, we developed and employed Hammett methodologies using selective hydrogenation of phenylacetylene to styrene. Though the reaction is typically carried out under high pressure of H2, parameters for the reaction at atmospheric pressure were determined to facilitate rapid and convenient collection of kinetic data. A full kinetic study of this reaction was performed in order to evaluate it as a test reaction for studying gold nanoparticle catalysts.

Funding Source: NSF Award #1300619 and American Chemical Society Petroleum Research Fund

Chemistry Session A Presentation 71 Ryan Lord Advisor: Dr. Chandler

Förster Resonance Energy Transfer on

Gold Self-Assembled Monolayers

Förster resonance energy transfer (FRET) is a mechanism that can be used to measure distances at the nanoscale level. FRET near gold surfaces and gratings have a number of applications for biological sensors; however, distance dependent interactions between the fluorophore and Au surfaces can have large effects on fluorescence. To better understand these effects we developed methods for controlling the distance between a fluorophore (NHS-rhodamine) and gold surfaces (films and gratings). A mercaptoundecanoic acid (MUA) self-assembled monolayer (SAM) was first prepared on a gold film. The carboxylic acid of MUA was then activated via anhydride formation, and amine-terminated polyamidoamine (PAMAM) dendrimers were added. The dendrimers form a monolayer to produce significant, variable spacing from the gold surface. The amine-reactive fluorophore, NHS-rhodamine, was used to label the terminal amines of the dendrimer-layered gold surface by amide bond formation. Fluorescence spectroscopy was used to confirm fluorophore attachment and measure fluorescence for the attached NHS-rhodamine. The extent of fluorescence was measured with respect to the concentration of fluorophore loaded onto the gold film.

Additional studies were performed with quantum dots, which are nanoparticle semiconductors. Eventually, the quantum dots can be used in conjunction with NHS-rhodamine to serve as a FRET pair for measuring FRET near gold surfaces. Cadmium telluride quantum dots were synthesized from CdCl2 and NaHTe solutions. Quantum dots have ideal properties for the study, as the fluorescence emission wavelength can be selectively synthesized. In addition, quantum dots are photostable. The nanoparticles optical properties were characterized by UV-Vis and fluorimeter measurements.


Chemistry Session A Presentation 72 Adhwaith Mani & Todd Whittaker

Advisors: Dr. Chandler & Dr. Pursell

Effects of water on CO oxidation and adsorption on supported Au nanoparticle catalysts

Supported Au catalysts are the most active low temperature CO oxidation catalysts known and we are studying the effect water has on their catalytic activity. To characterize the catalytic activity, CO adsorption and CO oxidation studies were conducted.

Understanding CO adsorption onto the gold is potentially important to understanding the overall activity of the catalyst. Fourier Transform Infrared (FTIR) spectroscopy was therefore used to analyze the thermodynamic behavior of CO adsorbing to different supported gold catalysts. The adsorption data was fit using the Temkin adsorption model which produced thermodynamic metrics such as K, ΔG, ΔH and δΔH (the change in ΔH with CO coverage). These values are used to understand the behavior of the catalyst and its relative activity.

Experiments to measure the relative CO oxidation activity were performed at room temperature in a glass reactor vessel. Different concentrations of water were added to the reactant mixture and the concentration of CO, O2 and CO2 were measured over time using an online gas IR analyzer. The relative conversion rate at different partial pressures of O2 were then determined from steady-state measurements. We found that the rate increases with water concentration up to a certain point and then levels off. We were also able to attribute the increase in rate to an increase in the number of active sites on the Au catalyst as opposed to a change in the inherent catalytic activity using data from last summer.

The presence of water has had an effect on the behavior of the catalyst, both in its conversion of CO to CO2 and in the way CO adsorbs to the Au surface. Further investigations will clarify the trends that have been initially observed in the current experiments.


Chemistry Session A Presentation 73 Hamilton Lee Advisor: Dr. Urbach

Co-Host Mediated Divalent Recognition of Peptides The ability to design receptors that selectively recognize peptides and proteins is

highly desirable in biochemical systems where the sensing and separation of target molecules in complex solutions are required. In previous work, the complex comprising the host cucurbit[8]uril and guest methyl viologen (i.e., the Q8•MV complex) can bind to peptides containing tryptophan (Trp) with high affinity and sequence specificity in aqueous solution. This project explores whether a modification to the viologen guest can improve the affinity and specificity of peptide binding. In collaboration with Zachary Ball's group at Rice University, a viologen modified with a dirhodium complex was synthesized with the goal of enhancing peptide binding via interaction of the RhRh moiety with the imidazole sidechain of a histidine (His) residue. Binding studies reveal an enhancement in binding affinity that is specific to peptides containing Trp and His with the modified viologen•Q8 complex.

Funding Source: The Camille & Henry Dreyfus Foundation, Inc., NSF Award #1309978, and Robert A. Welch Foundation

Chemistry Session A Presentation 74 David Leach Advisor: Dr. Urbach

Sequence-Specific, Nanomolar Peptide Binding via Folding and Inclusion of Neighboring Residues in Cucurbit[8]uril

This study demonstrates the sequence-specific, nanomolar binding of tripeptides by the synthetic receptor cucurbit[8]uril (Q8). This uniquely strong and specific recognition is made possible the folding and inclusion of two neighboring side chains within the Q8 cavity. The fluorescent dye tetramethylbenzobis(imidazolium) (MBBI) was used as a sensor component to study the binding of the Q8•MBBI complex to a library of 105 peptides that vary in the N-terminal residue (tyrosine, phenylalanine, and tryptophan) and in the identity of the neighboring residues (varied to 18 amino acids at each position). The fluorescence intensity of Q8•MBBI increased upon treatment with the peptide Tyr-Leu-Ala but decreased upon treatment with its sequence isomer Tyr-Ala-Leu. Further studies by 1H NMR spectroscopy, mass spectrometery, isothermal titration calorimetry, and fluorescence spectroscopy show that Tyr-Leu-Ala binds to Q8 in a 1:1 stoichiometric ratio, with an unprecedented dissociation constant of 7.2 nM, and with >4000-fold specificity versus Tyr-Ala-Leu due to the inclusion of the sidechains of the neighboring Tyr and Leu residues in Tyr-Leu-Ala. This novel binding mode was confirmed using a semiempirical caclulation involving NMR-derived distance restraints.

Funding Source: NSF Award #1309978, Robert A. Welch Foundation, and Camille and Henry Dreyfus Foundation

Chemistry Session B Presentation 75 Zachary Nickle Advisor: Dr. Bachrach

Exploring Flatter ExBox Host Analogs The ExBox4+ molecule is used to understand more about host-guest interactions. The

present goal is to explore potential hosts that might more strongly bind polycyclic aromatic hydrocarbon (PAH) guests. These PAHs include benzene, naphthalene, anthracene, and tetracene. The two ExBox4+ analogs studied have “flatter” top and bottom sections of the host molecule. DFT calculations (ωb97X-D/6-31G(d)) were run with and without the PAH guests, and the calculated energies were compared to the energies of the original ExBox4+.

Funding Source: Robert A. Welch Foundation, Trinity University

Chemistry Session B Presentation 76 Caileen Tallant Advisor: Dr. Bachrach

Exploring Wider ExBox Host Analogs The original ExBox4+ 1 structure, developed by Stoddart as a potential sequestering

agent for polycyclic aromatic hydrocarbons (PAHs), was altered computationally to form two possible hosts with wider tops and bases using benzo(rst)pentaphene 2 and a pyrimidine-quinoxaline-pyrimidine 3, respectively, in order to explore the binding of nonlinear PAHs in comparison with 1. It is predicted that having a nonlinear (wider) top and base will result in stronger binding with nonlinear (wider) guest molecules. Structures 2 and 3 and their host-guest complexes of both linear acenes (benzene, anthracene, and tetracene), and a nonlinear guest (pyrene) were optimized using DFT (ωB97X-D/6-31G(d)) in the gas phase. When comparing the host structures with the host-guest complexes, the minor axes decreased and the major axes increased when the guests were present. With both new hosts, the gas phase binding energy displayed a positive linear relationship with increasing size of each linear acene. Geometric conformations and binding energies are reported and compared to 1.

1

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Funding Source: Robert A. Welch Foundation

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Chemistry Session B Presentation 77 Natalie Seitzman Advisor: Dr. Bushey

XRF Analysis of Spanish Colonial Alamo Frescos Built in the 18th century, the Mission San Antonio de Valero, better known as the

Alamo, has become a cornerstone of Texas state history. Since its construction, the detailed frescos have deteriorated, but in recent cleanings of the interior walls, Alamo conservator Pamela Rosser, uncovered traces of those paintings from the early 1700s as well as other, more modern, pigments from the U.S. Army occupation in the 1860s. Elemental mapping of these traces offers the possibility of a reconstruction of the original designs and an image of the Alamo that hasn’t been seen in over a century. Within the mission’s sacristy, visible traces of a painted figure have been analyzed using portable x-ray fluorescence (PXRF), which uses x-ray energies characteristic of each element to determine elemental composition. Taking advantage of this method’s small size and non-destructive testing, a few red-orange lines and faint shadows on the sacristy walls have been reconstructed into an intricate Spanish colonial design.

Funding Source: Texas General Land Office

Chemistry Session B Presentation 78 Joel Adablah Advisor: Dr. Bushey

High resolution imaging of fused-silica capillaries containing a porous polymer laurel acrylate monolith using

scanning electron microscopy The Bushey lab has worked to further development in the field of monolithic

stationary phases for capillary electrochromatography (CEC). Specifically, our lab focuses on the characterization of fused-silica capillaries containing a laurel acrylate porous polymer monolith for their application to CEC. These columns have been used for in-depth CEC studies using the alkyl benzene series.

The secondary electron imaging mode of operation of the scanning electron microscope (SEM) produces highly detailed topographical images that are included in a myriad of important research papers in various scientific fields.

In this study, secondary electron images of cross sections of fused silica capillaries containing four different preparations of a laurel acrylate porous polymer monolith, i.e. with bi- and tridentate linkers BDDA and TMPTMA, respectively, with and without AMPS, were collected.

Observation of the globular polymeric structures in the high-resolution images collected at various magnifications provides immediately useful detail about the spatial organization of the polymer within the fused silica capillary.

In addition to structural data, Martin plots of all four capillaries types provided information about their quality and reproducibility, in addition to their retention of analytes in the neutral alkyl benzene series.

Funding Source: W. M. Keck Foundation

Chemistry Session B Presentation 79

Nico Dwarica Advisor: Dr. Kelly-Zion & Zach Tuten, & Dr. Pursell

Investigating Diffusive and Convective Vapor Transport Mechanisms for the Evaporation of Hydrocarbons

The evaporation of a drop of hydrocarbons at room temperature and atmospheric pressure is controlled by the rate of transport of vapors from the surface of the liquid. The transport of vapors away from the liquid can occur by means of a coupling of diffusion and convection mechanisms. Diffusion is driven by the concentration gradient, whereas convection is controlled by the density gradient of the vapor-air mixture. The motivation of our research is to analyze the roles of diffusion and natural convection in the evaporation process. Previous experiments with heavier molecules, such as hexane, indicate a dependence on convective transport. Methanol, with a density similar to that of air, should be more dominated by diffusion. To determine the dominant mechanism, we measured the vapor concentration in the cloud above the drop. We began by depositing a sessile drop of methanol on a substrate. A Fourier transform infrared spectrometer was used to measure the integrated absorbance at different positions above the droplet. Computed tomography was then used to determine the concentration as a function of height and radius from the drop using the measured integrated absorbance. This technique was also used previously to determine the vapor distribution of hexane.

Compared to the flattened vapor cloud created by evaporating hexane, shown in Figure 1, the methanol vapor tends to extend much farther upwards before diminishing. Diffusion tends to expand the vapor cloud. The larger methanol cloud implies that the convective forces, so prevalent for hexane vapor transport, are not as significant in methanol evaporation. It is hoped that, with further analysis of the measured results, the relative effects of diffusion and natural convection on the evaporation process can be more thoroughly understood.

Fig. 1: Concentration distribution for diffusion-limited evaporation and measured concentrations of hexane

Funding Source: Trinity University Murchison SURF Award and Robert A. Welch Foundation

Chemistry Session C Presentation 80 Leslie Cook, Lindsey Ulin, & Shelby Luikart

Advisor: Dr. Chandler

Characterization Studies of Gold Nanoparticle Catalysts Using

the Selective Oxidation of Benzyl Alcohol

We are interested in characterizing metal oxide supported gold nanoparticle catalysts such as Au/TiO2 and Au/Al2O3. We utilized the selective oxidation of benzyl alcohol as a probe reaction for determining and better understanding the inherent properties of the catalysts. These characterization studies looked at the adsorption of benzyl alcohol, the effects of the metal oxide support, basic kinetics, and the effects of water. The adsorption of benzyl alcohol is the first step in this reaction and experiments were done to determine where benzyl alcohol was adsorbed on the catalyst. The basic kinetics of the reaction were examined with Arrhenius and reaction order studies. We varied parameters such as the concentration of benzyl alcohol and temperature to determine the kinetic properties associated with the catalysts. Water effects were also examined with Hammett studies. We added differing amounts of water to the catalysts and examined whether their inherent electronic properties, represented by Hammett parameters, changed.

Funding Source: NSF Award #1300619, and Trinity University McNair Scholars Program

Chemistry Session C Presentation 81 Allison Levy Advisor: Dr. Lambert

NMR Classification of Fossilized Plant Exudates A plant exudate is any substance that is secreted from diseased or injured plant tissue.

Amber is an example of a fossilized plant exudate; currently, samples from resin blocks recovered from the 13th- century Java Sea Wreck, which is housed at the Field Museum, is being studied. The ultimate goal of this research is apply this analysis to our understanding of exchange and commerce in East and Southeast Asia and the Indian Ocean World in the early to mid-second millennium AD. The resins were analyzed by qualitative analysis of carbon and proton NMR spectra. The proton NMR sample consists of 55 mg of the fossilized resin and 1 mL of a solvent, usually CDCl3. This process is a quick, cost-effective, and non-destructive method for classifying plant exudates. Additionally a set of resins allegedly from Arkansas were also studied in order to determine provenance. Step Three: Add the name of the source or sources of your research funding in the field below.

Funding Source: Trinity University Murchison SURF Award and Camille & Henry Dreyfus Foundation

Chemistry Session C Presentation 82 Jasmine Rodriguez Advisor: Dr. Lambert

Determination of Piperidine Structure by NMR Spectroscopy Piperidine is a saturated, nitrogen-containing, six-membered ring. When looking

specifically at the hydrogen and lone pair on the nitrogen, it can be noted that piperidine has two conformations. In one form, the hydrogen is equatorial while the neighboring lone pair is axial; in the other form, the hydrogen is axial and the lone pair is equatorial.

The ultimate goal of this study is to use NMR spectroscopy to determine which form predominates and at what equilibrium. Many NMR spectra are obtained of piperidine in a variety of solvents with varying polarities. We will be specifically measuring the coupling between the carbon-13 atom next to the nitrogen and its attached hydrogen. N-methypiperidine is also analyzed as a comparison compound. These coupling constants will provide information about the relative size of the hydrogen atom and the lone pair and the electronic interactions of these two groups in the two conformations. Additionally, the equilibrium between axial and equatorial NH group will be determined.


Chemistry Session C Presentation 83 Brady Iba & Yizhou Zhao

Advisor: Dr. Bushey

Thermodynamic Studies of Retention on a Lauryl Acrylate Porous Polymer Monolith

To characterize a lauryl acrylate porous polymer monolith (PPM), the relationship between retention and temperature for a series of analytes was investigated. An alkyl benzene series (toluene through 1-phenyl octane) was used to probe the thermodynamics of retention over the range of 25 °C to 60 °C in 5 °C increments. This series was selected based on their use in our previous studies as well as appearance in other publications. The van’t Hoff relationship is ln(k) = -ΔH/RT + ΔS/R + ln(Φ), where k is the retention factor, ΔH and ΔS are enthalpy and entropy of partitioning, respectively, and Φ is the phase ratio (volume of stationary phase/volume of mobile phase), which was obtained through a nanoflow HPLC instrument. Finally, R and T are the gas constant and temperature, respectively. The enthalpy and entropy of partitioning are obtained from the slope and the y-intercept, respectively. Therefore, we are able to obtain the thermodynamic parameters of our lauryl acrylate (PPM) through this relationship. Both ΔH and ΔS were found to decrease as retention increases and since ΔG also decreases as increases, we concluded that retention on the lauryl acrylate PPM is enthalpically driven. Compared to more traditional stationary phases, changes in temperature produce a less dramatic enthalpic change. Probing of different mobile phase concentrations and its effect on retention is currently being conducted across the same temperature range to investigate retention with varying concentrations of organic material in the mobile phase.

Funding Source: NSF Award #1055516 and the American Chemical Society Petroleum Research Fund.

Chemistry Session C Presentation 84 Rohit Sampat & Pooja Bollampally

Advisor: Dr. Bushey

Characterization of Lauryl Acrylate Porous Polymer Monolith Stationary Phase In Capillary Electrochromatography Through

Diffusion Study

In chromatography, components of a sample are separated by the different distributions of analytes between a mobile phase and a stationary phase. Stationary phases exhibit different separation characteristics, which are dependent on the stationary phase’s structures and composition. Our research project takes interest in a recently developed stationary phase, a lauryl acrylate porous polymer monolith (PPM). We seek to better characterize its behavior through a diffusion study. The mobile phase in our study consists of various ratios of acetonitrile and an aqueous buffer. In our diffusion study we utilize the peak-parking method, allowing analytes to “sit” in the column for a certain time period. We measure the variance, or broadness of the peaks and we repeat the experiment without interrupting the movement of the analyte through the column. By subtracting the variance of the peak determined in the uninterrupted run from the case where the elution is interrupted, we determine the variance due to the diffusion that occurs during the ‘stopped time’. This allows us to measure the diffusion coefficient of the analyte. The relationship between diffusion and retention is then examined through use of the Knox equation, Deff = (γmDm+ kγsDs)/(1 + k). The PPM columns used in this study follow Knox behavior, unlike traditional columns.

Funding Source: American Chemical Society Petroleum Research Fund and NSF Award #1055516

Chemistry Session C Presentation 85 Rachel Felger, Jemma Ferguson, Janie Thompson, &Miguel Webber

Advisor: Dr. Mills

The Effect of Phenyl Substitution on Delocalization in Antiaromatic Bis-indenylidene Dications

Antiaromatic ions offer an interesting opportunity to examine factors that affect

delocalization. In these species, their charge benefits from enhanced delocalization, but their antiaromaticity works to minimize delocalization to enhance stability. Phenyl substituents, which stabilize charge, can be used to alter patterns of delocalization. The change in delocalization is then demonstrated by changes in antiaromaticity. We are interested in applying this premise to phenyl substituted dications of bis-indenylidenes. In order to synthesize the precursors to these phenyl substituted antiaromatic dications our synthetic scheme begins with the synthesis of 3-, 4-, 5-, and 6-phenyl-1-indanone.

The indanones are formed through different synthetic schemes. The synthesis of 4-phenyl-indanone and 6-phenyl indanone begins with reaction of Meldrum’s acid with 2-or 4-bromosubstituted bromobenzaldehyde, resulting ultimately in a 3-(bromophenyl)-propionic acid. Friedel-Crafts cyclization results in formation of the 1-indanone. Suzuki reaction with palladium acetate replaces the bromine with a benzene ring to give the 4- or 6-bromo-1-indanone. The synthesis of 3-phenyl-1-indanone begins with the reaction of the anion of dimethylmalonate with benzaldehyde to give an α,β-unsaturated diester. Conjugate addition of the phenyl Grignard results in a diphenyl diester, which is hydrolyzed and decarboxylated to give 3,3-diphenylpropionic acid which is cyclized to 3-phenyl-1-indanone. The 5-phenyl-1-indanone is created by a Suzuki reaction of 5-bromo-1-indanone with palladium acetate. The coupling of these indanones to diols followed by dehydration gives the dienes which are one step from the bis-allylic alcohols which are the precursors to the antiaromatic dications. Funding Source: Robert A. Welch Foundation and NSF Award #1265545

Chemistry Session D Presentation 86 Samuel Lee Advisor: Dr. Bachrach

Exploring the Mechanism of the Nucleophilic Substitution Reaction of Peroxides

The intramolecular reaction of carbanions with dialkyl peroxides, which results in the formation of cyclic ethers and various oxacycles, was recently proposed by Willand-Charnley, Puffer, and Dussault.1 This nontraditional approach to ether synthesis was examined at the B97X-D/6-311+G(d,p) level for the 4-, 5-, 6-, and 7-membered ring systems. Results indicate that at this level the reactions proceed via a pathway similar to the SN2 mechanism, as illustrated in Scheme 1, where acyclic 1 proceeds through transition state 2 to form the 5-membered ring 3. Structural and energetic results of the various conformers associated with each ring system are reported.

SCHEME 1.

1 Willand-Charnley, R.; Puffer, B.W.; Dussault P.H. J. Am. Chem. Soc. 2014, 136 (16), 5821-5823.


1 2 3

Chemistry Session D Presentation 87 Alex Huther & Caroline Kelleher

Advisor: Dr. Chandler

Alkyne hydrogenation over supported Au and Au-M catalysts

Gold nanoparticle catalysts are potentially useful in chemical, environmental and

pharmaceutical research because of their high selectivity, particularly in hydrogenation reactions. However, their activity is often limited by their ability to bind and activate hydrogen in the presence of other substrates. Developing new synthetic methods to prepare bimetallic Au-M nanoparticles may help to increase hydrogenation activity. We worked to synthesize bimetallic nanoparticles in efforts to increase alkyne hydrogenation while maintaining the high alkene selectivity of monometallic gold catalysts. The bimetallic catalysts were produced with the help of PANAM G5NH2 dendrimers in a methanol and lauric acid solution. The nanoparticles were then deposited onto a metal oxide support and the dendrimer thermally removed. A reaction system for evaluating 1-hexyne hydrogenation was built to evaluate sctalytic activity and selectivity.

Funding Source: Robert A. Welch Foundation & Trinity University

Chemistry Session D Presentation 88 Lucas Poliak & Cameron McKay

Dr. Mills

Exploration of Delocalization Patterns in Antiaromatic Bis-indenylidene Dications

The study of aromaticity examines molecules that contain conjugated pi bond systems and have 4nπ+2 electrons that are delocalized in order to stabilize the molecule. However, questions involving changes in delocalization are difficult to evaluate in aromatic species that tend toward complete delocalization. Antiaromatic species, on the other hand, resist delocalization, allowing a more sensitive measure of delocalization. The Mills research group is examining delocalization in bis-indenylidene dications, which are linked through the 6-membered ring. The final dication needed is one with a phenyl substituent on that 6-membered ring. The synthesis pathway for the dication precursor began with the reaction of Meldrum’s acid with 3,5-dibromobenzaldehyde followed by hydrolysis under microwave conditions to give a substituted propionic acid. Friedel-Crafts cyclization of the propionic acid with chlorosulfonic acid gave the desired 5,7-dibromo-1-indanone. Homocoupling of the indanone occurred with a palladium catalyst. The regiochemistry of that coupling will be discussed along with a subsequent Suzuki coupling to give the bis-7-phenylindanone that serves as the key compound for formation of the precursor to the desired dication.

Funding Source: NSF Award #1265545 and Robert A. Welch Foundation

O

Br

Br

OBr

O Br

O

O

Chemistry Session D Presentation 89 Vanessa Romano & William Mobley

Advisor: Dr. Mills

Synthesis of Precursors to Antiaromatic Thiophene Cations Our study of antiaromatic dications began with the synthesis of fulvalenes such as 1

shown below. The gift of 0.5 g of ketone 2 from Dr. Craig Hawker suggested to us the idea of synthesizing a family of antiaromatic thiophene dications, through the scheme shown below for 2.

2 3

According to the nucleus independent chemical shift values, (NICS) sulfur reduces the antiaromaticity of dications, presumably because it stabilizes the positive charge. Therefore, our research aimed to confirm the effect of sulfur atoms on antiaromaticity. We will be presenting our work on the synthesis of the precursors to our target thiophene dications 3-5 shown below.

1 3 4 5


Chemistry Session D Presentation 90 Nathan Webber Advisor:

Dr. Hunsicker-Wang

Investigation of the Effects of Overall Charge State on Ferredoxin Cluster Reduction Potential in the Thermus

Thermophilus Rieske Protein

The Rieske protein is found in the bc1 complex and plays an important role in biological functions as it takes part transporting electrons and protons through the electron transport chain. The Rieske protein contains a [2Fe-2S] cluster ligated by a 2-cystines and 2-histidines. The reduction potential of this cluster has a great range across species. Reduction potential has been postulated to be governed by the type of ligands, the number of hydrogen bonds, the proximity charged residues to and the solvent accessibility of the cluster. Another possible factor that could affect reduction potential is the overall charge state of the protein. To probe this factor, mutants with altered overall charge states have been produced which replace positively charged residues (R, K) with neutral or negatively charged residues (A, E). Characterization of these mutants is performed with DEPC modification studies using both Uv-Visible and Circular Dichroism spectroscopies. K100E has been characterized and exhibits, as expected, a pattern of both reduction and modification very similar to that observed for wild type. pH-dependent Uv-Visible studies will be conducted with each mutant so that pKa values can be calculated. Reduction potentials will also be measured in collaboration and compared to wild type.


Chemistry Session D Presentation 91 Matthew Ponthier Advisor:

Dr. Hunsicker-Wang

Probing the Factors that Affect Reduction Potential in the Thermus Thermophilus Rieske Protein

The Rieske protein is a part of the bc1 complex (complex III) in the electron transport chain. It contains a [2Fe-2S] cluster ligated by two histidines and two cysteines. The cluster’s reduction potential is pH-dependent and varies greatly among species. The factors that have been postulated to tune the reduction potential are the number of hydrogen bonds to, the proximity of charged residues to, and the solvent accessibility of the [2Fe-2S] cluster and its ligating histidines. L135E, L135R, L135A, and Y158F are mutants of Thermus thermophilus Rieske protein produced to test the various factors. L135E and L135R demonstrate the effect of proximal charged residues to the cluster, L135A exhibits increased solvent accessibility, and Y158F removes a hydrogen bond from the cluster. Reduction potential measurements of Y158F and L135R are in line with expectations, but L135A and L135E differ from the expected effects. Crystallographic studies have been performed to determine what changes, if any, have occurred in the structures of the proteins due to the mutations. Crystal structures of each mutant have been produced and are at various stages of completion. L135A has shown an elongated disulfide bond which may be the cause of the unusual reduction potential measurements. In the structure of L135E, there are differences in the cluster binding region that could be the source of the unexpected reduction potential measurements.


BCMB Showcase Presentation 92 Carolyn Young Advisor: Dr. Urbach

Insulin-Specific Inhibition of Insulin-Degrading Enzyme Using a Synthetic Receptor

Insulin is a hormone produced in the pancreas that regulates glucose metabolism. One way that insulin is degraded in the body is by a protein known as insulin-degrading enzyme (IDE). The synthetic receptor, cucurbit[7]uril (Q7), has been shown previously to bind with high affinity to the N-terminal phenylalanine of the B-chain of human insulin, which is also a site of specific interaction between insulin and IDE. In this project, we attempt to use Q7 to block the interaction of insulin with IDE and thereby inhibit the degradation of insulin by IDE. A time-resolved fluorescence assay using an antibody sandwich approach was used to determine the concentration of insulin at nanomolar concentrations before and after treatment with IDE and in the presence of Q7. In addition, the IDE-mediated degradation of insulin was monitored in time using HPLC.

Funding Source: Robert A. Welch Foundation and NSF Award #1309978

BCMB Showcase Presentation 93 Ronald Davenport-Dendy Advisor: Dr. Cheng

Computer Simulations of Beta-Amyloid Dimer Interactions with Lipid Rafts

Beta-amyloid’s (A-beta) interactions with neuronal membranes have been linked to the neurodegenerative Alzheimer’s disease. Using coarse-grained molecular dynamics simulations, we have studied the binding behavior and membrane disruption mechanisms of A-beta dimer on multicomponent lipid rafts consisting of liquid-ordered (Lo) and liquid-disordered (Ld) coexisting phases. Large size 3000 ns-simulations (> 50,000 united atoms) of five dimer/lipid raft systems have successfully been performed using both local and high performance computer clusters at Trinity and UT-Austin. Here the Lo phase consists mainly of saturated dipalmitoylphosphatidylcholine (DPPC) and cholesterol (CHOL), and the Ld phase predominately unsaturated dilinoleoylphosphatidylcholine (DUPC). We observed that A-beta dimers typically bind to lipid rafts at the Lo/Ld interface. When CHOL headgroups are reduced in polarity, the raft’s Lo and Ld domains became scattered; there was little organization within the raft, and no bonding occurred during a 3000 ns simulation. Conversely, when CHOL headgroups were polarized, the Lo/Ld interface became more distinct, and bonding was seen at this interface. We also placed multiple monosialotetrahexosylganglioside (GM1), lipids into the Lo domain of a lipid raft as well in order to mimic the neuronal plasma membrane nano-domain. Bonding was seen at 340 ns into the simulation, but rather than attaching itself to the Lo/Ld interface, the A-beta dimer bound itself to one of the GM1 clusters. Further analysis will be conducted to quantify 1) the minimum distance between A-beta and the lipids during the bonding event, 2) the extent to which dimer-lipid interaction affects the lipids orientation order, and 3) the z-direction density of the lipids within the raft before and after the bonding event. We predict that the apolar-modified CHOL raft will exhibit more symptoms of disorder: great changes in orientation order and z-based density. Simulations involving multiple dimers and detailed analysis of binding and membrane disruptions are still in progress.

Funding Source: Williams Endowment Fund of Trinity University and High Performance Computing Center of UT-Austin

BCMB Showcase Presentation 94 Hudson Smith Advisor: Dr. Martinez

Attempted Synthesis of Fluorescent and Benzophenone Labeled Metformin Analogs

Metformin is a well-known anti-diabetic medication that has a long been a standard treatment for noninsulin-dependent diabetes mellitus (type II diabetes). Recently, metformin has attracted increasing interest from the scientific community due to its application as a biological reagent in cancer and aging studies. The biological mechanisms by which metformin acts may be quite varied, and much is still not known. A fluorescently labeled analog of metformin would be valuable to researchers interested in better understanding metformin’s effects and exploiting potential applications at both the cellular and organismal level. Rhodamine 110, Rhodamine 123, and 4-aminobenzophenone were reacted with dicyandiamide using microwave irradiation. The resulting products were isolated and analyzed by high performance liquid chromatography (HPLC), mass spectrometry (MS), nuclear magnetic resonance spectrometry (NMR), and infrared spectrometry (IR). Initial optimization results will be presented. Funding Source: Trinity University

BCMB Showcase Presentation 95 Liezelle Lopez Advisor:

Dr. Hunsicker-Wang

Isolation and Characterization of a Mixed Disulfide Intermediate Between Thermus Thermophilus Sco and CuA

The Sco family of proteins has been implicated in the assembly of cytochrome c oxidase, the terminal enzyme of the respiratory electron transport chain, but its function is still the subject of much study and debate. For the Thermus thermophilus Sco (TtSco), it has been shown to be able to reduce the disulfide bond present in the CuA site of subunit II of cytochrome c oxidase prior to copper insertion. To provide evidence of Sco’s role as that of a thioredoxin and understand the mechanism of disulfide bond reduction in the assembly of the CuA protein from Thermus thermophilus (TtCuA), single cysteine to serine mutants, TtSco C53S and CuA, TtCuA C149S, were first expressed and purified. The latter was also conjugated to the chromophore, 2-nitro-5-thiobenzoate(TNB). TtSco C53S and TtCuA C149S were mixed and the reaction monitored via UV-Visible spectroscopy at 412 nm to monitor formation of a mixed disulfide intermediate (MDI) between the two proteins. The formation of the MDI was also confirmed through reducing and nonreducing SDS-PAGE gels. The current focus is on optimizing the purification and isolation of the MDI through affinity, size-exclusion, and ion exchange chromatography. Once enough MDI has been isolated, the species can be crystallized and characterized, providing definitive evidence that TtSco reduces the disulfide bond of TtCuA, and giving detailed information about the protein-protein interactions driving the formation of MDI.

Funding Source: Robert A. Welch Foundation, NSF Award #1058273

BCMB Showcase Presentation 96

Ambrose Paige Advisor: Dr. Hunsicker-Wang

Probing the 3 Cysteine, 1 Histidine Ligation Environment of a [2Fe-2S] Cluster

The Rieske protein is a [2Fe- 2S] cluster protein that is ligated by two histidines and two cysteines and is found in the bc1 complex (complex III) of the electron transport chain. It acts as an electron transport protein, removing an electron from ubiquinol and transferring it to cytochrome c. Its reduction potential is pH-dependent and varies across species. The ligation environment of the cluster can also be altered to a three cysteine and one histidine ligation environment by creating the H154C and H134C mutants. There have been two proteins found in nature with the 3 cysteine, 1 histidine ligation environment, IScU and MitoNEET, and they will be compared to the H134C and H154C mutants. The crystal structure of the H134C mutant is being refined. The mutant is also being created in the longer construct for reduction potential measurements. The H154C mutant has also been created to compare to the H134C mutant.


BCMB Showcase Presentation 97 Sara Vivatson Advisor: Dr. Urbach

Characterization of a Cucurbit[7]uril-Rhodamine Conjugate as a Chemical Sensor

Cucurbit[7]uril (Q7) is known for its binding to molecules such as insulin in aqueous solution. Previously, fluorescence assays using Q7 and fluorescent dyes were used to determine the binding affinities of Q7 with various analytes, but the working concentrations of the assays depended heavily on the binding affinity between Q7 and dye. The covalent attachment of Q7 to a fluorescent dye should remove this concentration dependence. The two-step synthesis of a Q7-rhodamine conjugate produced four isomers, which were separated by HPLC and isolated in pure form. Preliminary studies with one of these isomers (P1) demonstrated similar binding affinity as unmodified Q7 to peptides. Binding affinities were determined using the change in fluorescence of the rhodamine moiety upon binding. While replicating these data, several variables have been encountered which impact the fluorescence of the conjugates as a function of time, concentration, and container material. These variables suggest the influence of nonspecific adsorption of the conjugate to the walls of the container and potentially photobleaching of the dye. Ongoing studies are in progress to overcome this obstacle and validate the conjugates as chemical sensors.


BCMB Showcase Presentation 98 Amy Grice Advisor: Dr. Urbach

Development of a Cellular Probe Based on a Synthetic Receptor

The focus of this project was to develop a molecular probe for interfacing with biological systems. The probe was constructed from a synthetic receptor, cucurbit[7]uril (Q7), and a fluorescent dye, tetramethylrhodamine (TMR). The Q7-TMR conjugate was added to cultures of N27 and HT22 neuronal cells and imaging was performed using confocal microscopy. Fixed cell experiments show the internalization of Q7-TMR but it remains to be determined specifically where the conjugate localizes or whether that localization is driven by the binding of Q7 or another process. Experiments in live cells are ongoing.


Summer research students and faculty gather in May 2014

Thirty Years of Undergraduate Research Symposia at Trinity Although summer undergraduate research has been going on at Trinity since the 1950’s, the

first Undergraduate Research Symposium was sponsored by Trinity’s Chemistry department in 1984 and involved 10 participants. The 30th Anniversary of the Chemistry Undergraduate Research Symposium was celebrated on June 6, 2014, with a symposium of alumni presentations. From that beginning, Trinity’s Summer Undergraduate Research Program has grown to involve over 150 students and nearly 70 faculty members in 2014. This year’s conference will include nearly 100 posters and oral presentations.

The National Science Foundation has supported Research Experiences for Undergraduate (REU) Programs at Trinity in chemistry (1989-2000), mathematics (1997-2008) and computer science (2008-2010). In addition to individual faculty research grants, NSF currently supports Trinity programs for training science teachers (Robert Noyce Program) scholarships for STEM majors (FAST and FASTER Programs) and students interested in biomathematics (Interdisciplinary Training for Undergraduates in Biological and Mathematical Sciences program).

The Welch Foundation has supported student and faculty researchers in chemistry since 1997. In addition, grants from the Merck Foundation (2001-2009) and the W. M. Keck Foundation (2003) supported research collaborations between biologists and chemists.

Grants in 2004 and 2008 from the Howard Hughes Medical Institute have provided summer research fellowships for students in addition to transforming Trinity’s curricular offerings in the sciences and enhancing outreach to local schools.

In 2008, Trinity started a Ronald E. McNair Post-Baccalaureate Achievement Program with funding from the U.S. Department of Education.

In 2011, Trinity launched the Murchison Fellowships program, which funds 10 summer projects proposed by faculty-student teams.

In 2013, Trinity received support from the Andrew W. Mellon Foundation to support undergraduate research in the arts and humanities.

Trinity University is grateful to the following organizations and donors for their support.

American Chemical Society Petroleum Research Fund

Arnold & Mabel Beckman Foundation

Biology Summer Undergraduate Research Fund

Dow Corning Corporation

Camille & Henry Dreyfus Foundation, Inc.

Imogene and Harold Herndon Fund for Physical Science Research

Howland, Eggen, and Pitts Computer Science Student Summer Research Fellowship

Tim and Karen Hixon Endowment for Environmental Studies

W.M. Keck Foundation

Dr. Mark Kline

The Steven P. Mach Family

The Andrew W. Mellon Foundation

National Science Foundation

National Institutes of Health

Ronald E. McNair Scholars Program

T. Frank and Norine R. Murchison Faculty Development Fund Research Corporation

F.W. Olin - Entrepreneurship - E-Teams Endowment Fund

The Semmes Distinguished Scholars in Science Endowment Fund

Shell International Exploration and Production

Texas Ecolab

Texas General Land Office

Tinker Family Endowment for Geosciences

U.S. Department of Education

Robert A. Welch Foundation

Documents

Trinity University · Giovanni Giammanco Experiments and Simulations of . Escherichia coli. Chemotaxis . Healy & Nguyen Roland Green & Stefan Schluter Fast-SLAM implementation with