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Force measuring sensor for prevention of skin ulceration by

Ultraflex UltraSafeStepTM

Ankle-Foot Orthosis

Progress Report Draft

Team10

Christopher Grace

Matthew Gunn

Song Han

Jun Heo

Advisors: Miriam Ludwig, MS, OTR/L MBA MSME

Rami Seliktar, Ph.D

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Executive Summary

This project aims to design a sensor system to be implanted on an Ultraflex USS AFO that can measure ground reaction forces present in areas of known high rates of skin abrasion while the patient is standing

and walking. The design will be used as a research device to measure the forces within the AFO at the

boney prominences to correlate those pressures with the development of skin ulcers. Identifying areas

with the potential to cause damage to the wearer’s skin is important to altering the orthosis to ensure a more comfortable fit while preventing possible skin ulceration. The device consists of a multi-channel

nylon sock with force sensors impeded throughout the bottom of the foot. Each nylon sock liners contain

seven embedded pressure sensors that relay information to the computer in order to determine if the areas with high rates of abrasion are experiencing forces that may cause skin damage or discomfort. The device

is designed to detect the pressure baseline that creates ulcerations, which is 12.3kg/cm2, with an accuracy

of 1-2%. The resolution is design to be 0.10 kg/cm2, and the sensitivity should have a slope between 10

and 10,000 (μV vs. kg/cm2). Moreover, the noise to signal ratio needs to be 1:1000 due to the accuracy

required to effectively determine the limit of baseline pressure. The A-201 FlexiForce sensors used in the

project have been designed and operated within the force ranges of human gait and were chosen based on

width and thickness as well as its outstanding real-time dynamic output signal. The sensors will send an analog signal and be linked to an amplifying circuit which will produce data to be read. The resulted

analog signals will be converted to digital signal by analog-to-digital converter to be interpreted via a

LabVIEW program. Currently, we have successfully built a prototype that is capable of outputting voltage signal in response to the force. Although technical difficulties with the circuit’s assembly have delayed

the calibration and accuracy testing, they are still expected to be completed by March 9th 2010. Our final

goal is to test the design by conducting gait experiments of one human subject while wearing the custom fit AFO containing the sensors. Data will be recorded and evaluated for potential sites of skin irritation

from pressure placed by the AFO.

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Table of Contents

Executive Summary ................................................................................................................................ 2

List of figures and tables.......................................................................................................................... 4

List of abbreviations and definitions ........................................................................................................ 4

Introduction ............................................................................................................................................. 5

Problem Statement............................................................................................................................... 5

Solution ............................................................................................................................................... 7

Specifications ...................................................................................................................................... 7

Description of Prototype to date............................................................................................................... 8

Liner ................................................................................................................................................... 8

Sensors ................................................................................................................................................ 9

Circuit ................................................................................................................................................. 9

Meeting the design specifications ....................................................................................................... 11

Current Prototype .............................................................................................................................. 11

Calibration ........................................................................................................................................ 12

Plan of action for spring term ................................................................................................................ 12

Human testing ................................................................................................................................... 12

Environmental impact............................................................................................................................ 13

Schedule................................................................................................................................................ 13

Completed ......................................................................................................................................... 13

Tasks to be done ................................................................................................................................ 14

Reference .............................................................................................................................................. 15

Appendix .............................................................................................................................................. 16

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List of figures and tables

Figure 1: Diagram of the nylon liner with several pockets housed with sensors.

Figure 2: A-201 FlexiForce sensor

Figure 3: Operational amplifier set of for Tekscan sensor obtained from Tekscan website

Figure 4: Pressure distribution by anatomical region of bottom of the foot. Normalized maximum pressure distribution for the young (white bar) and elderly (black bar) group for each anatomical region (medial

calcalneus mask p = 0.0001, lateral calcaneus mask p = 0.03). Approved to use by Hessert et al. BMC

Geriatrics 2005 5:8 doi:10.1186/1471-2318-5-8

Table 1: Physical properties of the A-201 FlexiForce sensor

Table 2: Typical performance and evaluation conditions of A-201 FlexiForce sensor

List of abbreviations and definitions

ADC: Analog-to-digital converter

AFO: Ankle-foot orthosis

MTS machine: Machine Testing & Simulation machine

Ultraflex USS AFO: Ultraflex UltraSafeStepTM Ankle-Foot Orthosis

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Introduction

Problem Statement

Stroke victims can incur a condition known as hemi-paresis or hemi-plegia. These conditions

cause weakness, partial paralysis, and over activity or both in muscles on one side of the body. A

common manifestation of these conditions is foot drop. Two types of foot drop can be found in stroke

victims. One occurs when damage to the peroneal nerve results in where muscle weakness prevents leg

muscles from being able to raise the foot and it will fall limply at the ankle joint into plantar flexion.

Another type occurs when over activity in these uncontrolled muscles forces the foot down into plantar

flexion and the opposing muscle groups cannot overcome this force due to weakness. In this case the foot

will be stuck down into plantar flexion. Both types of foot drop can seriously impair an individual’s

ability to walk and often results in falls which are extremely dangerous for individuals whom have

already sustain brain lesion.

Foot drop is currently treated with an ankle-foot orthosis (AFO), which stabilizes the foot and

restores the ability for normal gait. AFO are designed to aid in stabilizing the foot, leg, and ankle through

mechanical means attempting to restore ability lost by the leg and foot muscles. AFOs attempt to restore

normal gait to patients suffering from foot drop restraining movement of the leg, ankle, and foot by

mechanically doing work of the lost muscle function (Blaya 2004). The problem affecting AFO wearers

are the development of skin ulcerations due to an ill-fitting device. The most common places for skin

ulceration are found on the boney prominences on the bottom of the foot. These include the protrusions of

the metatarsal bones on each of the five digits and the anterior and posterior protrusions of the calcaneus

(heel) bone (Veves et al. 1992). Skin ulceration is caused by abnormally high pressures in these areas, and

further data on the threshold where abnormal pressure leads to skin damage is determined to be

12.3kg/cm2 according to the experiment performed by Veves et al, who studied the risk of foot ulceration

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in diabetic patients with high foot pressure (1992). Typical forces during walking are found to be upwards

of 4.5% of their total body weight (Hessert et al. 2005). Forces that can cause damage exceed this

approximation, and need to be studied further to identify what constitutes too much force for AFO

wearers.

There is a need for a research device that can be used measure the forces within the AFO at the

boney prominences to correlate those pressures with the development of skin ulcers. The device must also

be able to be adjustable to the differences between patients feet, accurate enough to measure the

difference between expected normal forces and abnormal forces, and accurate while the patient walk

while wearing the AFO. Accuracy of the solution should be within the range of 1-2% of a patient’s

weight to accurately distinguish between normal and abnormal forces.

With this device researchers will be able to make measurements of forces at each of the indicated

locations during a session of gait analysis. Follow up studies will indicate if an ulceration has developed

and the corresponding location on the bottom of the patient’s foot. This data can then be correlated to the

forces measured in that location during the gait analysis. This device will provide a tool for researchers to

gather data about the occurrence of foot ulcers and their relationship to forces experienced while wearing

AFOs.

The objective of this project is the development of a device that can be worn with an AFO that is

capable of measuring the ground reaction forces present on the skin from the AFO at the identified boney

prominences while the patient is standing and walking. The deliverable will present a solution to solve the

need for this research device.

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Solution

In order to solve the problem stated above, we are intended to design and build a device that

consists of a two layer nylon sock with 7 Tekscan force sensors impeded throughout the bottom of the

foot connected to amplifiers with flat wire cable. The sensors will be located on the protrusions of the

metatarsal bones on each of the five digits (5 sensors) and the anterior and posterior protrusions of the

calcaneus bone (2 sensors). This tests the areas that most likely to form ulcerations.

Specifications

The highest pressure distribution on the bottom of the foot is 4.5% BM/cm2 (Appendix Figure 4).

Therefore, maximum force needs to be measured: 4.5% BW/cm2× body weight of patients (lb) ×the

sensing area of the sensor (cm2) (Hessert et al., 2005).

As described in introduction, the pressure baseline to create ulcerations is 12.3kg/cm2 based on

the study on the development of ulcerations of subject with neuropathy, neuropathy and diabetes, and

without any disease (Veves et al. 1992). Having an accuracy of sensors to be 1-2% can provide readings

that are accurate to 0.12kg/cm2. According to researchers, the accuracy is acceptable in research.

The resolution will then have to be high enough to easily see a 0.10 kg/cm2 difference, and the

sensitivity should have a slope no less than 10 and no more than 10,000 (μV vs. kg/cm2) as anything

below or above the limit may not give an accurate reading within the circuit and amplifier. The limit of

detection should be 1% body weight or less as that is the least amount of force seen on the foot during

gait.

The noise to signal ratio needs to be 1:1000 due to the accuracy needed to effectively determine

the limit of 12.3 kg/cm2 before ulceration occurs. Both signals are amplified together, it would need to be

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103 less for the noise to measure in a range of 0 to 0.01 and would not alter results enough to interfere

with reading the limit of 12.3 kg/cm2.

Description of Prototype to date

Liner

As shown in Figure 1, a layer of nylon is diagonally sewn onto a nylon sock to create channels

(shown by dashed lines), and each sensor (black dot) is housed within a channel that works as a pocket.

The sensors can move along the channel freely and also be housed in different channel. Therefore,

orthotist can identify boney prominences by palpation and adjust the position of sensors to measure the

force at intended areas for patients with various foot sizes.

Figure 1: Diagram of the nylon liner with several pockets housed with sensors.

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Sensors

Figure 2: A-201 FlexiForce sensor

A-201 FlexiForce sensors are common but very accurate force resistive sensors widely used for

various applications. Maximum force is assumed to be 25 lb. The sensor with force range of 0-25 lb will

be used.

Fg = 4.5% BW/cm2× body weight of patients (lb) ×the sensing area of the sensor (cm

2)

= 4.5% /cm2× 200 lb × 2.85 cm

2

= 25.65 lb

Theoretically, sensor range of 0-100 can be used for patients weigh over 200 lbs.

According to sensor specification provided by Tekscan Inc., the sensor has accuracy of 5% and

can be varied depending on how well variables (repeatability, linearity, temperature difference,

calibration) can be controlled. Actual accuracy in data output of our system will need to be calculated

during calibration process. Sensitivity of the sensor can be freely adjusted using Tekscan’s recommended

circuit presented in the proposal. The sensor’s frequency response is 2 kHz, generating 2,000 data per

second.

Circuit

The circuit is to be comprised of one Tekscan sensor, a potentiometer, 0.25mm flat wire cable,

and an amplifier. The amplifier creates a gain for the signal produced when the sensor converts

mechanical force into an electrical signal in microvolts. The signal will run across the op amp creating the

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gain up to five volts, the recommended amount for the Tekscan sensor. The increased signal will allow

better analyzation. The voltage is then connected to the inverting portion of the operational amplifier

while the non-inverting portion is grounded. The flat cable wires are chosen to be 0.25 mm because they

are thinner than the thickness of the sensor.

Figure 3: Operational amplifier set of for Tekscan sensor obtained from Tekscan website

The equation for the circuit given by Tekscan:

Vout = -Vt*(Rf/Rs)

Vout = Signal output

Vt = input offset voltage

Rf = resistance of the resistor

Rs = impedance of the sensor

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The amplifier will be attached to the outside of the AFO to reduce the amount of noise by

minimizing the wire length. An A to D converter will be used to convert the signal into a digital form, so

that the signal can be inputted into a computer. LabVIEW will be used to record the signal and plot the

signal volts vs. time. This graph will help us determine the amount of force applied to the sensor by

analyzing the volts. The peak and average force values for every sensor will be recorded and graphed in

Matlab.

Meeting the design specifications

The circuit and sensors as a whole will meet the design specification in all areas except for

accuracy as it will slightly be out of the ideal range. The sensors used will be able to detect the amount of

force that is applied in individuals weighing 100-200 lbs while standing or during gait. The ideal accuracy

needed will be 1-2% for a detection of 0.12-0.24 lbs/cm2 and the Tekscan sensors have a +/-5% accuracy

which will display 0.60 lbs/cm2. Although this does not meet the ideal accuracy, the sensors ability to

detect forces at a 5% accuracy will give useable results for the prototype. The Tekscan sensor’s

sensitivity can be adjusted depending on the type of amplifier used and ambient temperature to meet the

ideal sensitivity range of 10 to a 1000 (μV vs. kg/cm2).

Current Prototype

A single circuit has been built on a breadboard and consists of an operational amplifier, a

potentiometer, and single sensor. A potentiometer is being used in place of a conventional resistor for the

Rf value. This creates the possibility to adjust the resistance across the amplifier creating differences in the

total gain. At 35 KΩ and 2 KHz, the gain is approximately 9. This was enough to amplify a signal from

100 mVs to nearly 1 V. Problems with the 741 op amp failures and inconsistency led to testing of the

remaining integrated circuits. Three operational amplifiers were built and tested to find differences in the

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gain at the same input frequency (2 KHz), voltage (100 mV) and Rf value (90 KΩ). Two operational

amplifiers were found to have the same gain of 2.7 while the third one had 2.44. Testing of each op amp

will be necessary to calibrate the device to ensure that each sensor-circuit component is accurate.

Technical difficulties with the circuit’s assembly have pushed back the calibration and accuracy testing to

a later date. Once both properties are measured and determined to meet the specifications, six more

amplifiers and sensors circuits will be constructed, tested and connected with flat wire cable. The sensors

will then be placed in the multi-channel liner and tested in customized Ultraflex UltraSafeStepTM

AFO.

The sensor was roughly tested in the circuit to see if it had an impact on the output voltage. The outgoing

signal at baseline is approximately 15 mV and rose to 1.1 V when an unmeasured amount of force was

applied.

Calibration

Sensor’s electrical output needs to be related to an actual engineering unit, pounds, with

calibration method. To calibrate, a known force to the sensor will be applied by Instron, and sensor

resistance output to this force will be equated. After repeating this step with a number of known forces

with Instron, force versus conductance (1/R) can be plotted. A linear interpolation can be done between

zero load and the known calibration loads to determine the actual force range that matches the sensor

output range.

Plan of action for spring term

Human testing

Human testing will be used to test the devices ability to measure normal forces of the foot and

determine if the accuracy and precision necessary for the researcher to collect data. This will be

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conducted by volunteers in the lab. The volunteer will walk in an orthotic that correctly fits him/her and

the forces will be recorded. Only one volunteer will be studied as the orthotic will be built to

accommodate the subject’s anatomy. The volunteer will walk normally in the orthotic with the results of

the gait forces recorded. The volunteer will then again walk in the orthotic but with a modified shoe insert

that will create an increase of material in the area of first metatarsal and proximal phalanx of the hallux

joint. This increase will presumably show a force increase, possibly above 12.3kg/cm2, as the insert

concentrates forces onto the specific area.

Environmental impact

The development of this device will have significant affects on the medical knowledge dealing

with the treatment of pressure sores of AFO wearers. With the data collected with this research device, a

correlation between abnormal forces experienced between AFO assisted gait and pressure sore

development on the bottom of the foot can be create. This data can be used to further enhance research

methods for studying AFO assisted gait as well as the prevention of pressure sores through early

identification methods. In the future the occurrence of pressure sore formation for AFO wearers can be

reduced and thus reduce the medical expense for the treatment of this affliction.

Schedule

Completed

We visited Manufacture Dept. of Ultraflex, Inc on Oct 12th, 2009 to experience the manufacturing

process and collect relevant preliminary data on gait analysis. Then, we have determined a need for a

sensing device to improve interaction between the custom fit AFOs and the patients. During the month of

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October, continuously consulted many professionals in the field, we have found a company, Tekscan,

Inc., producing various force sensors. The signal analysis program, LabVIEW is studied by Matt Gunn

and Christopher Grace. Matt Gunn has taken a laboratory class dealing with sensor system and circuits

and has successfully incorporating learned skills to build the physical circuit system. On January 2009,

the design specifications including location of sensors, circuit diagram, and detailed structure of the

device were finalized. The prototype (amplifier and sensor) was built in Dr. Pouzzeraei’s bio sensor lab

with help of his graduate students. Although we have encountered technical difficulties throughout the

process, the amplifier connected to sensor successfully sent out signals.

Tasks to be done

By end of term, we expect to run calibration and collect other data to determine accuracy,

sensitivity and signal to noise ratio. Although sensors were intended to be calibrated and tested for

accuracy before March 2nd

, technical difficulties with the circuit’s assembly have pushed back the

calibration and accuracy testing to a later date (expected to be done by March 9th). By the end of March,

problems of the prototype will be determined and improvements will be made. We expect to have

multiple tests to determine the method to maximize the accuracy of the data and minimize the signal to

noise ratio. During winter term, final design will be completed and test within the custom fit AFO

manufactured at Ultraflex, Inc. Finally, in-orthosis analysis will be performed to identify the forces

exerted by dynamic movement of the human subject.

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Reference

Blaya, J.A., Herr, H. (2004). Adaptive control of a variable-impedance ankle-foot orthosis to assist drop.

Neural Systems and Rehabilitation Engineering. March 2004, Volume 12(1), pp- 24-31.

Cowley Matthew S., Boyko, Edward J., Shofer, Jane B., Ahroni, Jessie H.,Ledoux, William R. (2008).

Foot ulcer risk and location in relation to prospective clinicalassessment of foot shape and mobility among persons with diabetes. Diabetes Research and Clinical Practice, Volume 82,

Issue 2, November 2008, pp 226-232

Emmons, Kevin. R. MSN, RN, CWCN., Newland, Elena. PT, MS. (2009). Intent to Prevent: Proactivity is essential to preventing pressure sores. Interdisciplinary Journal of Rehabilitation. 9 March

2009, pp 34-37.

Hessert, Mary. Foot pressure distribution during walking in young and old adults. Division of

Gerontology, Beth Israel Deaconess Medical Center Harvard Medical School, Boston USA.

http://www.biomedcentral.com/1471-2318/5/8. Pub. May 19 2005.

Leung, Joan,. Moseley, Anne. (2003). Impact of ankle-foot orthoses on gait and leg muscle activity in

adults with hemiplegia. Physiotherapy.2003. Volume 89, pp-33-59.

Oh-Park, Mooyeon, MD., Park, Geun, MD, PhD., Hosamane, Sadvi MD., Kim, Dennis D. MD. (2007).

Proximally Placed Alignment Control Strap for Ankle Varus Deformity: A Case Report. Archives

of Physical Medicine and Rehabilitation, Volume 88, Issue 1, January 2007, pp 120-123

Piezo systems. <http://www.piezo.com/orderpricelist.html>. Accessed 31 October 2009.

Tekscan. < http://www.tekscan.com/index.html>. Accessed 29 October 2009.

Ultraflex. <www.ultraflexsystems.com>. Accessed 3 October 2009.

Veves, A., Murray, H.J., Young, M.J., Boulton, A.J. (1992) The risk of foot ulceration in diabetic patients

with high foot pressure:a prospective study. Diabetologia. Volume 35, ages 660-663

Walid, M. S., M. Ajjan, N. Patel & T. Guta. (2007). Cellulitis May Present As Foot Drop In A Diabetic

Patient . The Internet Journal of Neurology. Volume 7 Number 1

Whittle Michael. Gait Analysis an introduction-3rd

Edition. Butterworth-Heinemann. Woburn, MA. c 2002.

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Appendix

Physical Properties of the sensor

Thickness 0.008" (0.208 mm)

Length 7.75" (197 mm),

optional trimmed lengths 6” (152 mm), 4” (102 mm), or 2” (51mm)

Width 0.55" (14 mm)

Sensing Area 0.375" diameter (9.53 mm)

Connector 3-pin Male Square Pin (center pin is inactive)

Substrate Polyester (ex: Mylar)

Standard Force Ranges 0 - 1 lb. (4.4 N)

0 - 25 lb. (110 N)

0 - 100 lb. (440 N)

Table 1: Physical properties of the A-201 FlexiForce sensor

Typical Performance Evaluation Conditions

Linearity (Error) ±3% Line drawn from 0 to 50% load

Repeatability ±2.5% of full scale Conditioned sensor, 80% of full force

applied

Hysteresis < 4.5 % of full scale Conditioned sensor, 80% of full force

applied

Drift < 5% per logarithmic time scale Constant load of 25 lb (111 N)

Response Time < 5 μsec Impact load, output recorded on

oscilloscope

Time required for the sensor to respond

to an input force

Operating Temperature 15°F - 140°F (-9°C -

60°C)

Output Change/Degree F ±0.2%/ºF (0.36%/ºC)

Table 2: Typical performance and evaluation conditions of A-201 FlexiForce sensor

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Figure 4: Pressure distribution by anatomical region of bottom of the foot. Normalized

maximum pressure distribution for the young (white bar) and elderly (black bar) group for each

anatomical region (medial calcalneus mask p = 0.0001, lateral calcaneus mask p = 0.03).

Approved to use by Hessert et al. BMC Geriatrics 2005 5:8 doi:10.1186/1471-2318-5-8

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Christopher Grace 269 Cheswold Road Drexel Hill, PA 19026

610-733-7825 christopher.michael.grace@drexel.edu

Education Drexel University Philadelphia, PA Bachelor of Science in Biomedical Engineering Anticipated Graduation - June, 2010 GPA: 3.56 Relevant Coursework

Living Systems I,II Living System Transport Human Physiology I,II Molecular Biology Cell Biology Thermodynamics Chemistry and Biology I,II,III

Electrical Circuits Biomechanics Lab Ultrasound Lab Biomaterials Tissue Engineering Organic Chemistry I,II,III/Lab I,II

Psychology

Work Experience

Protez Pharmaceuticals Malvern PA Microbiologist April 2009 – September 2009 • Screened of compounds and antibiotics against bacterial strains • Raised bacterial cultures • Maintained human cell lines for drug toxicity testing • Executed of organism identification assay • Analyzed bacterial growth for drug concentration effectiveness • Organized and maintained sterile lab environment Moss Rehabilitation Hospital Elkins Park, PA Rehab Technician April to September, 2008 • Worked closely with physician and therapists during clinical practice and evaluations • Procured patient vital signs, relevent medical histories, prepared medical reports • Operated EMG recording equipment and software during clinical exams • Photographed and videotaped patient movements for use in diagnosis • Prepared medications and provided assistance for patient injections • Observed physician rounds and medical procedures on traumatic brain injury floors Exponent Inc. Philadelphia, PA Engineering Assistant April to September, 2007 • Assisted a team of engineers in the medical devices department • Conducted material and chemical analysis of implant retrievals • Generated computer renderings of three-dimensional wear surfaces • Performed tissue sectioning, staining, and imaging • Prepared presentations of research for corporate and academic audiences

Honors and Awards • AJ Drexel Academic Scholarship • CEO Certificate in Emerging Leadership • College of Engineering Dean's List • School of Biomedical Engineering Dean's List

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Song Han 1318 Morris Street

Philadelphia, PA 19148 215-667-9464

song.han@drexel.edu

Education

Drexel University Philadelphia, PA Bachelor of Science in Biomedical Engineering Anticipated Graduation - June, 2010 GPA: 3.55

Relevant Coursework

lntroduction to Biomedical Engineering The Body Synthetic Engineering Principles of Living Systems l&ll Biomedical Engineering Lab l&ll Human Physiology l&ll Organic Chemistry l&ll Principle of Cell Biology Techniques in Cell Biology lntroduction to Thermodynamics Electric Circuits Engineering Mechanics: Statics Linear Modeling

Laboratory Skills

• Electrophoresis • Western blotting • Centrifugation • Bradford assay • Spectrometer • Polymerase chain reaction • Enzyme-Linked lmmunoSorbent Assay • Pipeting • Electrocardiograph • Electromyography • Electrooculography

Computer Skills

• Operating Systems: Microsoft Windows XP/Vista • Software: AutoCAD, Maple, Matlab, Labview, BSL Pro, Microsoft Word, Excel, PowerPoint

Relevant Experience

Electrophoretic Analysis of Serum Proteins & LDH Drexel University, Philadelphia, PA Researcher June to July, 2008

• Utilized protein eletrophorestic techniques to identify major serum proteins including albumin, transferring, antibodies and lactate dehydrogenase.

• Performed protein fingerprinting to compare the forms of LDH found in the serum of various mammals to investigate evolutionary relationships and then identified LDH isoenzymes found in various tissue types.

Purification and Analysis of Serum Albumin Drexel University, Philadelphia, PA Researcher July, 2008

• Employed affinity chromatography and Western blotting .to purify serum albumin. • Used peptide mapping to compare the structural relatedness of serum albumin from different sources.

Cell Fractionation and Analysis of SDH in Liver Drexel University, Philadelphia, PA Researcher July to August, 2008

• Fractionated cellular components isolated by centrifugation to obtain the nuclear, mitochondrial and microsomal fractions from the cell homogenates.

• Determined the protein concentration in the fractions by the Bradford assay and monitored the fractions for specific activity of succinate dehydrogenase (SDH) to study the role of this enzyme in cell respiration.

Evaluation of Expression Levels by ELISA and PCR Drexel University, Philadelphia, PA Researcher August, 2008

• Performed ELISA and Real-Time PCR to test the human peripheral blood mononuclear cell in respond to infection stimulation, lipopolysaccarides (LPS).

Honors

• Drexel University's Dean's Scholarship,2006-Present • Star Organization of the month, January 2008

Activities

• Drexel Table Tennis Club, Position: treasurer • Drexel Badminton Club

21

Jun Hyuk Heo 228 Farleigh Court

Langhorne, PA 19047

267. 986. 9966

jh429@drexel.edu

Education

Drexel University Philadelphia, PA

Bachelor of Science in Biomedical Engineering Anticipated Graduation - June, 2010

Biomaterials and tissue engineering Cumulative GPA 3.16

Laboratory Skills • Centrifugation, micropipetting, protein separation and quantification, and gel electrophoresis

• Western blot, ELISA, PCR analysis, and RNA extractions.

• Techniques of gene cloning: isolation of chDNA, restriction digestion, ligation, transformation, screening of clones, plasmid mini-preps, and

restriction mapping

• Recrystallization, distillation, extraction, and chromatography techniques of organic compounds

• Designing and executing physiological experiments and analysis of physiological data using Matlab simulation

• Data acquisition and analysis of physiological/biological/functional signals using ECG and EMG techniques

• Testing and analyzing mechanical properties of biological tissues using machinery laboratory equipments

• Conducting analysis, report data, and generate final reports

Relevant Experience

Merck & Co., Inc. West Point, PA

Merck Research Laboratory Co-op September 2008 to March 2009 • Worked closely in a team environment with Biologists and Biochemists in the Dept. of Molecular Endocrinology to carry

out biochemical and cell-based biological assays that support the development of novel therapeutics for skeletal diseases

• Attended department meetings and journal clubs to follow-up on current state of neuromuscular and skeletal diseases

• Completed training for radiation safety, laboratory safety, and lab notebook maintenance and successfully incorporated the

skills learned into practice

• Handled various laboratory equipments from simple tools to instruments of state-of-the-art technology

• Conducted quantitative analysis of bone changes using computer tomographic and histomorphometric techniques

• Verified lack of instruction for microCT and created a new comprehensive manual to promote a quick learning process for

incoming interns.

Engineering Design Project • Designed an affordable electronic textbook with wi-fi communication and schedule management system

• Designed a closed-loop automatic system of insulin pump and glucose monitoring device

Honors and Awards • Drexel University Dean's Scholarship, 2006-Present

• Third Degree Black Belt Certification in Tae Kwon Do, 2007

Skills • Software: Microsoft Office Suite, AutoCAD, SolidWorks, Image-PRO, Adobe Photoshop, Adobe Premiere, Maple,

MathWorks, Matlab, Labview, BSL Pro

• Language: Fluent Korean

Additional Experience

Central Communication Service Inc. Elkins Park, PA Translator/News Editor July 2006 to September 2008 • Searched for local news and translated articles into Korean. Articles were posted on Korean Daily Newspaper in NY, NJ,

PA

• Collaborated with senior reporters to cover local political events

• Worked as translator to help non-English speaking Koreans in various cases from billing issues to municipal court matters

22

Bucks County Presbyterian Church Summer School Langhorne, PA

Tae Kwon Do Instructor June 2007 to September 2007 • Instructed Tae Kwon Do and other various physical activities to 30+ children

• Served as a role model to inspire moral values, humility, and other ethical principles of Martial Arts

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