Symposium Booklet - UTA ACES... · 2017-10-19 · 8:00am Registration opens. 8:00am until 8:30am...

ACESThe 13th Annual Celebration

of Excellence by Students

March 22, 2017

Symposium Booklet

WELCOME

THE ANNUAL CELEBRATION OF EXCELLENCE BY STUDENTS (ACES)

E.E. HEREFORD UNIVERSITY CENTER MARCH 22, 2017

We are delighted to welcome you to UT Arlington's thirteenth Annual Celebration of Excellence by Students (ACES). UT Arlington’s strength is built upon innovative thinking and creative work in the arts, humanities and social sciences, as well as in the sciences and technical and professional disciplines ACES shines a spotlight on intellectual curiosity, rigorous inquiry and the pursuit of excellence students display in their original research and creative projects. You will find the hard work, skill and knowledge displayed by our students both exciting and compelling. We want to express gratitude to the faculty mentors, both on and off campus, who have enriched the educational experiences of our students and have helped prepare the ACES participants for today's symposium. The time and attention you devote to your students in order to involve them in your research programs and creative endeavors are shaping tomorrow’s scholars and professionals. Finally, we take this opportunity to recognize and thank the outstanding contributions of the Office of Graduate Studies staff, our faculty and alumni judges, the Graduate Student Senate and our student volunteers. All of them have worked hard and spent long hours making sure the Thirteenth Annual Celebration of Excellence by Students is a memorable one. For more information about this year’s ACES event or to read about past ACES events and winners, please visit our website at www.uta.edu/aces. Dr. Duane Dimos Vice President for Research and Dean of Graduate Studies and The ACES Steering Committee

http://www.uta.edu/aces

Keynote Speaker

Geeth Chettiar is a Senior Technical Fellow in Engineering and Technical Operations at Lockheed Martin Aeronautics. She has been with Lockheed Martin for 25 years. Geeth is a leader with a broad experience base, as she has worked in the majority of the business areas within Lockheed Martin and at many locations throughout her career. She has contributed in numerous domains including Program Management, Systems Engineering,

Technical Fellow, Software Systems, Business Development, Human Resources and Program Capture. Additionally she is experienced with products in Satellite Space systems, Ground Systems, Intelligence Applications Systems and Aircrafts. Geeth is a graduate of the University of Maryland where she received both her Bachelor of Science and Master of Science Degree in Electrical Engineering. Geeth is a member of AIAA and IEEE and also serves on the advisory board of the College of Engineering at University of Texas at Arlington.

Acknowledgements

ACES was sponsored by the Office of the Provost, and the Office of Research and Graduate Studies. Support was also provided by the College of Architecture, Planning and Public Affairs; College of Business; College of Education; College of Engineering; College of Liberal Arts; College of Science; and the College of Nursing and Health Innovation.

ACES 2017 Steering Committee

Amy Austin, Assistant Professor, Foreign Languages, College of Liberal Arts

Brenda Davis, Coordinator, Office of Graduate Studies

Clifton Evans, Assistant Professor, Music, College of Liberal Arts

Greg Frazier, Professor, Associate Dean, College of Science

James Grover, Professor, Associate Dean, College of Science

Raymond Jackson (Chair) Associate Dean, Office of Graduate Studies

Alisa Johnson, Director of Educational Research

Jennifer Knight, Executive Assistant, Office of Graduate Studies

Mark LaVelle, Assistant Vice President, Office of Development

Daniel Levine, Professor, Psychology, College of Science

Maria Martinez-Cosio, Assistant Vice Provost for Faculty Development, Vice Provost for Faculty Affairs

Patrick Miller, Residence Director, Apartment and Resident Life, Student Affairs

Ignacio Ruiz-Perez, Associate Professor, Modern Languages

Mahera Philobos, Assistant Vice President for Research

Ashley Purgason, Assistant Vice President for Strategic Initiatives

Joan Reinhardt, Director, McNair Scholars Program, University College

Les Riding-In, Assistant Dean, College of Liberal Arts

Laurel Smith Stvan, Associate Professor and Chair, Linguistics, College of Liberal Arts

Gretchen Trkay, Department Head, UTA Libraries

Kelly Visnak, Associate University Librarian, UTA Libraries

Faedra Wills, Digital Project Librarian, UTA Libraries

Volunteers and Other Sources of Invaluable Assistance

Faculty Judges

Doctoral Student Judges

Graduate Student Senate

UT Arlington Staff Volunteers

UT Arlington Student Volunteers

Division of Student Affairs

Tina Gil, Aramark Catering

Stephanie Edgett, Conference Coordinator, E.H. Hereford University Center.

UT Arlington Facilities Management and Central Receiving

ACES Symposium Schedule At-a-Glance

8:00am Registration opens.

8:00am until 8:30am Poster Installation in the Bluebonnet Ballroom. No posters will be installed after 8:30am for the morning session

9:00am until 11:00am Judging of posters from the following colleges: College of Business, College of Education, College of Nursing and Health Innovation, College of Science, and School of Social Work. Student presenters must be present during the entire judging session. Poster Session open for viewing by general public in Bluebonnet Ballroom.

12:00am until 12:30pm

Removal of morning posters.

12:30pm until 1:00pm Poster Installation in the Bluebonnet Ballroom. No posters will be installed after 1:00pm for the afternoon session

1:30pm until 3:30pm Judging of posters from the following colleges: College of Architecture, Planning and Public Affairs; College of Liberal Arts, and College of Engineering. Student presenters must be present during the entire judging session. Poster Session open for viewing by general public in Bluebonnet Ballroom.

4:30pm until 5:00pm Removal of afternoon posters.

4:30pm until 5:00pm Judging rubrics available to all student presenters and Reception, Rio Grande, 2nd Floor University Center

5:00pm Reception and Presentation of Awards, Rio Grande Ballroom, 2nd Floor University Center

Morning Poster Session - Graduate Students (9:00am - 11:00am) Poster Number Name Major

1 Ayda Mirsalehi BIOL 2 Goutam Sarker BIOL 3 Emmanuel Varona - Torres CHEM 4 Allegra Leghissa CHEM 5 Tharun Teja Ponduru CHEM 6 Devaborniny Parasar CHEM 7 A. Paige Wicker CHEM 8 Tiffany Liden CHEM 9 Paola Sotelo CHEM

10 Atreyi Dasmahapatra CHEM 11 Susana Aguirre-Medel CHEM 12 Ilia Ponomarev CHEM 13 Jamie Schenk CHEM 14 Jayanta K Chakrabarty CHEM 15 Zixiang Fang CHEM 16 Pooja Ramanuj CHEM 17 Maheshika Wanigasekara CHEM 18 Yehia Baghdady CHEM 19 Chuong Nguyen CHEM 20 A D A Shahinuzzaman CHEM 21 Lindsay Davis CHEM 22 Denzel Pugh CHEM 23 Min Gao EES 24 Upasana Dhar EES 25 Emmanuel Higa EES 26 Ohood Alsalem EES 27 Daniel Valencia EES 28 Imelda Trejo MATH 29 Domi Jin PHYS 30 Cong Zhao PHYS 31 Michael Greene PHYS 32 Noura Dawas Alkhladi PHYS 33 Ananta Raj Chalise PHYS 34 Sajib Barman PHYS 35 Hori Pada Sarker PHYS 36 Shafaq Amdani Moten PHYS 37 Richard Bonde PHYS 38 Edan Bainglass PHYS

39 Shane Snyder PSYC 40 Zachary Warman PSYC 69 Kristen Ravi SOCW 70 Skylar M.G. Joyner SOCW 72 Maria Cole SOCW 73 Veronica Lopez SOCW 74 Anh Phuong Nguyen SOCW 76 Jin Chung MARK 77 Samia Jannat MANA 78 Christi Butler CURR 79 Valerie Maxine Hernandez CURR 80 Maria Delgado EDLE 82 Chadwick Fuchs KINE 83 Seungyong Lee KINE

Morning Poster Session - Undergraduate Students (9:00am - 11:00am) Poster Number Name Major

41 Jaclyn Bazaldua BIOL 42 Caleb Butler BIOL 43 Leia Klinger BIOL 44 Christina Koo BIOL 45 Eyad Shihabeddin BIOL 46 Jessica Lilley CHEM 47 Melissa Orr CHEM 48 Misty Martin CHEM 49 Nadine Shihabeddin CHEM 50 Michelle Reyes CHEM 51 Denise Reyes CHEM 52 Zaynab Omisade CHEM 53 Shariq Haseen CHEM 54 Edgar Rodriguez CHEM 55 Armin Oloumi CHEM 56 Halie Rion CHEM 57 Aaron West CHEM 58 Stephanie Dinh CHEM 59 Mary Gockenbach MATH 60 Elizabeth Stephenson MATH 61 Eric Amador PHYS 62 Darshan Chalise PHYS 63 Niyousha Davachi PHYS 64 Sydney Cox PSYC 65 Robert Tait PSYC 66 Nasheha Baset PSYC 67 Lou Lindley PSYC 68 Frank Cooley PSYC 75 Shivam Arora FINA 81 Chase Newby KINE

Afternoon Poster Session - Graduate Students (1:30pm - 3:30pm) Poster Number Name Major

9 Loveneesh Rana AE

10 Aneetta Kuriakose BE 11 Tamara Hill BE 12 Loan Bui BE 13 Dona Padanilam BE 14 Meghana Hosahalli Shivananda Murthy BE 15 Gowtham Krishnan Murugesan BE 16 Daniya Umer BE 17 Hien Lam BE 18 Tyrell Pruitt BE 19 Sahil Sunil Nalawade BE 20 Hai Nguyen CE 21 Sirwan Shahooei CE 22 Gomathy Radhakrishna Iyer CE 23 Hoda Rahimi CE 24 Madhuri Debnath CSE 25 Xiaolei Ren CSE 26 Md Sohel Mahmood EE 27 Mustafa Alam EE 28 Nicholas King IMSE 29 Unmesh Vishwas Tamhankar IMSE 30 Anish Kalliguddi IMSE 31 Vinay Sharma MSE 32 Nilay K. Srivastava ME 33 Sandeep Patil ME 34 Ashley Guy ME 35 Abhishek Chatterjee ME 36 Vimalan Adaikalanathan ME 59 Ahoura Zandiatashbar UPPP 60 Zedan Xu COMM 61 Samuel Fatzinger ENGL 62 Angela D. Mack ENGL 63 Robert Caldwell HIST 64 Abdulrahman Dallak LING 65 Juliet Huynh LING 66 Shannon Belden LING 67 Darcey Browning LING 68 Kevin Daily LING

69 Seula Han LING 70 Carly J. Sommerlot LING 71 Ehsan Shafiee Zargar LING 72 DeAnne Hurtado POLS 73 Natalie Thomas POLS 74 Richard Irwin POLS

Afternoon Poster Session - Undergraduate Students

(1:30pm - 3:30pm) Poster Number Name Major

37 Alexandra Kessler AE 38 Gilberto Olvera AE 39 Matthew Muir BE 40 Valinda Jones BE 41 Kelli Greenwood CE 42 Lucas Hoyos CE 43 Dylan Ebert CSE 44 Armaan Zirakchi CSE 45 Divya Chalise ME 46 Nicolas Long ME 47 Bilal Ahmed ME 75 Esther Kentish ENGL 76 Noemi Rodriguez SOCI/ANTH 77 Courtney Cantu HIST

Poster Number: 1

Bluebonnet Ballroom, Morning Session, 9:00 AM to 11:00 AM

Functional Analysis of Dntf-2r and Ran-like Nuclear Transport Retrogenes in Drosophila melanogaster

Presenter: Ayda Mirsalehi, Biology Graduate Student

Mentor: Dr Esther Betrán

Group Members: Diwash Jangam, Susana Domingues and Esther Betrán

Abstract:

In the evolutionary history of all organisms, changes to genetic components have always been present. However, only a fraction of the DNA changes in the genome contributes to changes in the individual's phenotype and adaptation. One kind of genomic change that is likely to have phenotypic consequence is the emergence of a new gene through gene duplication.

Gene duplication is a process that results in the production of an additional copy of a gene. The newly formed gene copies will most often acquire disablements or be deleted from the genome. However, under certain circumstances, the new gene copy might stay functional (e.g., if it provides a beneficial extra dose of the gene product). Dntf-2 and Ran are two examples of genes that have experienced RNA-mediated duplications in Drosophila. This process is called retroduplication. Dntf-2 and Ran are nuclear transport genes that physically interact and are essential in every cell because they play a central role in the transport of proteins from the cytoplasm to the nucleus of the cells.

Interestingly, the retroduplication of Dntf-2 and Ran has been recurrent in Drosophila (i.e., comparative genomics reveals at least three independent events for each of the genes) and the retrogenes are expressed nearly exclusively in male germline and evolving under positive selection. This is surprising since these genes are housekeeping that are needed in every cell. To elucidate the reasons for the selective pressures that lead to recurrent duplication of Dntf-2 and Ran, I am studying the function of these genes in the model organism Drosophila melanogaster.

Several approaches have been implemented to this end. We have data of the proteins' localizations during spermatogenesis from transgenic flies carrying gene fusions under the native regulatory region. Recently, we have generated transgenic flies carrying null mutations (i.e., knockouts) in the Dntf-2r and Ran-like genes (copies of Dntf-2 and Ran that exist in D. melanogaster). These are mutants for Dntf-2r and Ran-like where the genes have been replaced by a red fluorescent protein reporter in the eye by taking advantage of CRISPR/Cas9 technique combined with homologous recombination.

RNA-mediated interference (RNAi) technique has also been used in order to suppress the expression (i.e., knockdown) of these genes. Results from a detailed study of the effects of these knockouts and knockdowns in Dntf-2r and Ran-like retrogenes in male germline will be discussed.

Poster Number: 2


The first complete phylogeny of Southeast Asian toads (Anura: Bufonidae) reveals a new genus endemic to Sumatra

Presenter: Goutam Sarker, Biology Graduate Student

Mentor: Eric N. Smith

Group Members: Amir Hamidy and Nia Kurniawan

Abstract:

We present the first study to examine the phylogenetic relationships between all extant Southeast Asian and East Asian toad genera (Amphibia: Bufonidae). Our molecular and morphological data reveal the presence of a previously unknown genus of toad endemic to the island of Sumatra. Furthermore, the results of our analysis are contrary to previous studies and show that Bufo japonicus forms a distinct clade that is basal to all of the Southeast Asian bufonids except the genus Leptophryne and the new genus from Sumatra. This finding highlights the importance of comprehensive taxonomic sampling in phylogenetic analyses.

Poster Number: 3


Assessing the Environmental Impact of Unconventional Drilling on Soil in South Texas

Presenter: Emmanuel Varona - Torres, Chemistry and Biochemistry Graduate Student

Mentor: Kevin A. Schug

Group Members: Doug D. Carlton Jr, Zacariah L. Hildenbrand,

Abstract:

The wide and increasing use of fossil fuel extraction (i.e. hydraulic fracturing, and other drilling and well-stimulation techniques) in the United States and in other countries have gained national attention due to the public’s concern about the environmental and human health implications such activities may have. With any fossil fuel extraction, there is the potential for the release of pollutants into the air, ground water, and soil. Soil can be easily contaminated by hazardous semivolatile organic compounds, such as benzene, toluene, ethylbenzene, and xylene isomers (BTEX). In this study, soil samples were collected from a large ranch in the Eagle Ford Shale region in South Texas with 8 pad sites that accommodate 28 horizontal oil wells with 10 gas flares. The samples were analyzed using an Environmental Protection Agency standardized method. BTEX compounds were more prevalent than previously predicted in and around unconventional drilling activity. Flaring is likely the primary source of air contamination with accumulation occurring in the surrounding soil.

Poster Number: 4


Qualitative determination of enantiomeric terpenes in hops using gas chromatography â€“ mass spectrometry

Presenter: Allegra Leghissa, Chemistry and Biochemistry Graduate Student


Abstract:

Terpenes are a class of chemical compounds that derive from isoprene subunits, and that can be divided into 8 different subcategories, based on the length of their chain. These compounds represent the primary aromatic principles found in the essential oils of plants, and many of them are chiral. It is extremely important to differentiate between the enantiomers of each terpene not only because the two different forms carry different odors and flavors, but also because they are a testimony of the different growing conditions of the plants. To determine the enantiomeric terpenes using gas chromatography-mass spectrometry, a method featuring a beta-cyclodextrin stationary phase was used to separate the enantiomers. The separation was achieved through a slow temperature ramp (1.25Â°C/min) and a fast linear velocity (44.2 cm/s). The complexity of the plant matrix was overcome by the use of the multiple reaction monitoring mode on a triple quadrupole mass spectrometer, which allows the selection of specific fragment ion transitions, for high specificity detection. This new method for detecting terpenes could be applied to all types of plants, and it could also be used to more fully characterize different strains and cultivars in hops.

Poster Number: 5


Oxidation Chemistry of Aromatic Hydrocarbons using Earth-Friendly Metal Catalysts

Presenter: Tharun Teja Ponduru, Chemistry and Biochemistry Graduate Student

Mentor: Dr. Rasika Dias

Abstract:

The selective activation of carbon-hydrogen (C-H) bonds of aromatic hydrocarbons, namely benzene, and anthracene, is one of the most important, yet challenging processes in chemistry. These aromatic C-H bonds are relatively inert and harder to activate, especially in a selective manner. Among the various methods for C-H bond activation, selective and catalytic oxidation routes provide the simplest way to produce many industrially valuable chemicals such as alcohols and carbonyl compounds from readily available constituents of natural gas and petroleum feedstocks. Indeed, a number of very important industrial processes are currently in operation for this purpose. However, these processes often require harsh conditions (high temperature-high pressure, acid medium) and suffer from low selectivity usually due to over-oxidation. Thus, there is clearly a need for a more efficient, milder, and environmentally friendly technology. In our research, we would like to investigate these processes using earth-friendly metal catalysts and greener oxidants. Here we will mainly utilize metal adducts of fluorinated systems as catalysts because they would most likely last longer and tolerate highly oxidizing conditions. We have done some preliminary work and the results are promising. We can selectively convert benzene to phenol using 4% catalyst loading. Thus far the conversion is low but the selectivity is superb. More importantly, ours is an acid-free process. Preliminary work involving anthracene also gave outstanding results using the same reaction conditions. We are further interested in knowing how this process works in detail. I will be presenting these new findings along with its further research.

Poster Number: 6


Light emitting molecules involving copper

Presenter: Devaborniny Parasar, Chemistry and Biochemistry Graduate Student

Mentor: Dr. Rasika Dias

Abstract:

Photoluminescence is the emission of light by a substance subjected to an external stimuli or photons. There are several everyday materials like glow sticks, paint, and dyes that show this phenomenon. In the past few decades this phenomenon has come a long way from being used ubiquitously in everyday material to safety indicators for emergency wayfinding, finger print detectors, optical brighteners and so on. Owing to their high sensitivity and varied applicability, these materials have attracted much attention of the scientific community in the recent times, and thus have become an inevitable topic of research in the modern scientific fields of chemistry. Considering the importance and current interest of luminescent materials, we have developed some copper based pyrazole-alkyne complexes (PAC) showing this phenomenon. These light emitting molecules were characterized by X-ray and other techniques. By varying the stoichiometric ratio of the combining reagents we can change the structure and geometry of the resulting complexes. We can also tune the luminescence properties of the copper based PAC by changing the stoichiometry of the contributing reagents. In solid state, these PAC exhibits bright orange luminescence. These interesting complexes warrant further investigation on how the luminescence properties observed for these complexes can be utilized to incorporate them for sensing applications. Herein, we will discuss the synthesis, characterization and photoluminescence phenomenon of the above-mentioned complexes.

Poster Number: 7


Online SFE-SFC-MS for Direct Extraction and Analysis of Designer Drugs in Urine Samples

Presenter: A. Paige Wicker, Chemistry and Biochemistry Graduate Student


Group Members: Changling Qiu, Volodymyr Pauk, Karel Lemr, Vladimir Havlicek

Abstract:

Every year new designer drugs flood the recreational drug market as substitutes for controlled substances. These isomeric drugs maintain the bioactivity of traditional drugs, while limiting their analytical determination by currently established methods. Coupling supercritical fluid extraction (SFE) on-line with supercritical fluid chromatography (SFC) is a relatively new technique in the realm of analytical chemistry. It holds with it the promise of minimal sample preparation, minimal sample loss or contamination, and a tremendous decrease in total analysis time. The purpose of this work is to identify and optimize the most important parameters for detecting designer drugs by SFE-SFC/MS to keep up with their fast development. Parameters optimized included chromatography modifier, makeup solvent flow, time of extraction (both static and dynamic), extraction modifier, and back pressure regulator split ratio. Urine was used to evaluate biological matrix effects in SFC-MS. Preliminary data shows low makeup flow increases signal intensity, while high makeup flow shortens retention time and improves peak shape. Extraction is optimized with low addition of modifier during static stage, and addition of no modifier during dynamic stage. SFE-SFC provides a platform for analyte extraction, separation, and identification, all in a single analysis. In combination with mass spectrometry, SFE-SFC is a desirable technique for toxicological and clinical analyses, such as the rapid identification of new designer drugs in biological fluids.

Poster Number: 8


A Comparative Assessment of the Constituents in Produced Water Across the Nation from Unconventional Oil and Gas Operations

Presenter: Tiffany Liden, Chemistry and Biochemistry Graduate Student

Mentor: Dr. Kevin Schug

Group Members: Dr. Doug Carlton Jr.

Abstract:

Unconventional oil and gas practice are essential to meet society's growing energy needs. However, a byproduct of the process is the generation of large volumes of produced water (PW) from the natural formation, which can be 7-8 times greater by volume than the oil produced at a given oil field. (Ã‡akmakce, Kayaalp, & Koyuncu, 2008) The volume of PW has increased from 18 billion barrels (bbl) to 21 billion bbl generated annually from 1985-2007. (Clark & Veil, 2009) Currently, Class II disposal well commonly referred to salt water disposal wells (SWD) are the most popular disposal option because they are frequently the most cost effective and manageable chose. However, as regulations become more stringent and the volume of waste is an ever-growing problem, the cost to dispose of it will climb. In order, to maintain an economically viable situation new options need to be evaluated to handle the wastewater generated. This adage commonly touted in modern culture "Reduce, Reuse, Recycle"� can be a difficult goal to meet with complex waste samples. For PW from the oil and gas industry, a targeted remediation approach would be the best option. However, targeted treatment requires overcoming the hurdle of understanding the variety of composition and characteristics of the produced water as well as the consistence over the life of the well. A comparative study was performed to analyze produced water constituents. Six produced water samples were collected from a salt water disposal (SWD) site in the Permian Basin, 5 prior to any treatment at the SWD site and 1 after treatment. The constituents were compared to a data base of 166,000 samples from across the nation.

Poster Number: 9


Syntheses and structures of CeCu6.09Ga6.78, NdCu5.59 Ga7.29, PrCu4.33Ga6.67 and PrCu0.86Ga3.14: Exploring the NaZn13, BaHg11 and BaAl4 structures types

Presenter: Paola Sotelo, Chemistry and Biochemistry Graduate Student

Mentor: Robin Macaluso

Abstract:

Intermetallic compounds adopting the NaZn13, BaHg11 and BaAl4 structures types are important in permanent magnetic materials, magnetocaloric materials and unconventional heavy-fermion superconductors. In our studies of these type of structures, we have prepared by the flux growth method. single crystals of CeCu6.09Ga6.78 and NdCu5.59Ga7.29 which crystallize in the cubic system NaZn13 structure type, space group Fm-3c with Z = 8, a ~ 11.83 Ã…. Also for the first time, we prepared single crystals of PrCu4.33Ga6.67, which adopts a BaHg11 structure type (space group Pm-3m with Z = 3 and a ~8.30) and the PrCu0.86Ga3.14 phase adopting the BaAl4 structure type. In addition to synthetic and structural characterization by diffraction methods, the poster will highlight LMTO calculations on the tetragonal phase PrCu0.86Ga3.14 which from the best of our knowledge has not been reported.

Poster Number: 10


Modeling amorphous Silicon Nitride: A comparative study using empirical potentials

Presenter: Atreyi Dasmahapatra, Chemistry and Biochemistry Graduate Student

Mentor: Peter Kroll

Abstract:

Silicon Nitride (Si3N4) is a ceramic material that has applications in various fields such as in high temperature coatings and gate dielectric devices. In this work, we model amorphous silicon nitride (a-Si3N4) using empirical potentials. Our goal is a comparative study between various empirical potentials available for modeling a-Si3N4. Potentials considered are - Tersoff potential with 5 different parameter sets, Marian-Gastreich two-body potential (MG2), Marian-Gastreich three-body potential (MG3) and Vashishta (V) Potential.

For each potential set, we generate 10 models with target densities of 2.6, 2.7, 2.8, 2.9, 3.0, 3.1, 3.2, 3.3 and 3.4 gâ€¢cm-3. For 8 different potential sets and 9 different densities, we accumulate 720 models. Each model has 448 atoms, with 192 atoms of Si and 256 atoms of N. Models are first generated using a classical molecular dynamics involving empirical potentials and later optimized with respect to atom positions with accurate quantum mechanical computations.

In a perfect model of a-Si3N4, Si is 4-fold and N is 3-fold coordinated. However, our results indicate that all 5 parameterizations of the Tersoff potential have a tendency to under coordinate atoms, i.e., a considerable percentage of Si is 2 and 3 fold coordinated while N is 2 fold connected. Experimental observations of an under-coordinated atom denotes high reactivity of the bond. Thus, these models are not realistic. Alternatively, the MG3 potential over-coordinates atoms. We see presence of 5 and 6 fold coordinated Si and 4 fold connect N in models with MG3 potential. The V Potential has a preference to produce semi-crystalline or â€œorderedâ€� arrangement of atoms which is rather unexpected in an amorphous model. The MG2 potential produces amorphous structures with least percentage of under/over-coordinated atoms. The study of site-site distance distance pair correlation of atoms in models also echo these structural trends.

Thermodynamic data, in particular, enthalpy of formation (Î”Hf) indicates that all five parameterizations of the Tersoff potentials overestimate Î”Hf while MG2, MG3 and V potential models predict Î”Hf in the expected range of 0.2-0.3 eV/atom.

Thus, with respect to structure and energetics, we propose that the best empirical potential to be considered while modeling a-Si3N4 is the Marian Gastreich two body potential (MG2). The MG2 potential generates realistic models that are comparable to that obtained from accurate quantum mechanical modeling.

Poster Number: 11


Porous Silicon Oxycarbide (SiCO) Materials and Potential Applications

Presenter: Susana Aguirre-Medel, Chemistry and Biochemistry Graduate Student

Mentor: Peter Kroll

Group Members: Jared Enriquez

Abstract:

We report synthesis of porous silicon oxycarbide (SiCO) materials, their microstructural characterization and performance in environmental applications. One of processes consists of reacting siloxane precursors containing Si-H bonds with cross-linkers bearing vinyl groups using a platinum catalyst. The reaction in diluted solutions (80-95 vol%) converts the siloxanes into aerogels after supercritical drying in CO2. The other synthesis method involves hydrolysis and condensation reactions to obtain a cross-linked gel which is slowly dried at 45 Â°C to obtain a porous material.

Porous SiCO materials are transformed via thermal treatment in controlled atmospheres into SiCO ceramics. In addition, we augment the chemical synthesis by various treatments to tailor microstructural and chemical properties of aerogels. We characterize the porous SiCO materialsâ€™ specific surface area, nanoparticle size, pore size distribution, average pore size and total porosity. We emphasize the microstructural tailoring by heat treatment atmosphere and additional post-synthesis methods. We also study the potential applications of these materials, specifically the effects of different microstructures on their properties.

Poster Number: 12


Computational Studies of Crystalline and Amorphous Silicon Nitrides

Presenter: Ilia Ponomarev, Chemistry and Biochemistry Graduate Student

Mentor: Peter Kroll

Group Members: Rachel Lopes

Abstract:

Silicon nitride is a hard solid with high melting point. Silicon-nitride-based materials, both crystalline and amorphous, find a broad spectrum of high-tech applications such as turbocharges in automobile engines, ball bearings, space rocket engines, medical equipment, and cutting tools.

Better insight in local structure amorphous of silicon nitride can benefit in expanding the range of potential applications and lowering the cost of siicon-nitride-based materials. Nuclear Magnetic Resonance (NMR) is a method that is capable of providing such kind of information, but first we need to figure out how changes of local environment of atoms reflect on NMR parameters. This is where quantum-chemical calculations are necessary.

In this study we investigate NMR of crystalline and amorphous silicon nitride compounds using Density-Functional Theory (DFT) calculations and Gauge Including Projected Augmented Wave (GIPAW) method. We calculate NMR parameters of known crystalline silicon nitrides to establish gauge between computed values and experimentally measured ones. NMR calculations for hypothetical crystalline structures of silicon nitride as well as distorted known ones allow us to relate changes in local structure of Si atom to changes in Si-29 NMR chemical shifts. We compare these relations to the ones known for silicon oxide systems. We also find out what chemical shift 5-coordinated silicon is supposed to have in nitride systems.

We model amorphous silicon nitride using modified Wooten-Winer-Wearie (WWW) network algorithm and compute NMR parameters of these models, and use relations established for crystalline models to interpretation of NMR of amorphous silicon nitride materials.

Poster Number: 13


Resin-Coated Proppant Analysis for Formaldehyde Content by GC-MS Headspace, GC-VUV and HPLC.

Presenter: Jamie Schenk, Chemistry and Biochemistry Graduate Student

Mentor: Kevin Schug

Group Members: Doug Carlton, Jonathan Smuts, Ty Hanna, Danny Durham

Abstract:

Proppants are sand-like material used in hydraulic fracturing to keep fissures in shale rock open. These proppants can be coated with different types of compounds to help increase their productivity and reliance under harsh down-hole conditions but little research has been performed to examine the leaching of compounds, such as formaldehyde, from these resin coatings. In these experiments, two different types of proppants, phenol-formaldehyde and polyurethane, are examined for their leaching capacity. Formaldehyde is a pollutant in the atmosphere and high exposure for an extended amount of time has been linked to some types of cancers. Approximately 1000 mg of each proppant was weighed into headspace vials. Into each vial was distributed 2 mL of derivatizing agent, 1% p-toluenesulfonic acid in ethanol, and left to leach into the solvent for 20 hours. The samples were then analyzed using headspace sampling on GCMS-TQ8030 equipped with a ZB-WAXplus column. Results showed that the two phenyl-formaldehyde coated resins A and B had a leaching capacity of 0.125 and 0.133 milligrams of formaldehyde per milligram of proppant, respectively. The two polyurethane resin coated proppants were also examined but their responses were below the detection limit. These methods will be compared to other analytical techniques for formaldehyde testing to compare the capabilities/limits of formaldehyde leaching from the different proppants. Ultimately, the goal is to understand leaching properties of proppants under conditions relevant to their use in the field.

Poster Number: 14


A dual cleavable cross-linker (DUCCT) with enrichment functionality: a powerful technique for identification of cross-linked peptides with high confidence

Presenter: Jayanta K Chakrabarty, Chemistry and Biochemistry Graduate Student

Mentor: Saiful M Chowdhury

Group Members: Abu Hena M Kamal, Zixiang Fang

Abstract:

Protein-protein interactions are essential to understand protein functions in cellular systems. Mass spectrometry-based chemical cross-linking technique is a potential tool for identifying the protein-protein interactions. Low abundance of cross-linked products and data complexity are two major challenges in the protein cross-linking research field. We developed a new dual cleavable cross-linking technology with biotin affinity group (DUCCT-Biotin). Our cross-linker contains N-hydroxysuccinimide (NHS) esters that can usually react with primary amines. Moreover, biotin affinity tag can bind with avidin bead that helped to pull down the cross-linked products selectively by affinity chromatography. CID (collision induced dissociation) and ETD (electron transfer dissociation) fragmentation cleaved the cross-linker in specified positions and produced two signature mass spectra of the same cross-linked peptide. We also developed a bio-informatics tool to analyze cross-linked peptides.

For proof of concept, the cross-linker (DUCCT-Biotin) was initially tested using some model peptides (neurotensin and bradykinin). The complementary CID-MS/MS and ETD-MS/MS generate signature fragments from same cross-linked products give us high confidence in identification the cross-linked products (both dead-end and inter cross-linked peptides). Currently, we are studying the efficiency of our cross-linker in different proteins (ubiquitin, BSA, hemoglobin) and protein complexes, such as EGFR-EGF protein complex. We believe this approach will identify cross-linked peptides confidently from complex samples.

Poster Number: 15


Strategies for Enriching Farnesyl Peptide from Proteins Complex and Identifying using Mass Spectrometry

Presenter: Zixiang Fang, Chemistry and Biochemistry Graduate Student

Mentor: Saiful M. Chowdhury

Group Members: Kamal, Abu Hena Mostafa; Chakrabarty, Jayanta; Wanigasekara, Maheshika S; Shahinuzzaman, A.D.A; Ramanuj, Pooja Rajeshbhai

Abstract:

Prenylation is an important post-translational modification of proteins due to addition of isoprenoid lipids. It directs certain cellular localization of proteins and downstream signaling cascades. Protein prenylation includes farnsylation and geranyl-geranylation. The attachment of prenyl group happens in the cysteine at the C-terminal of proteins. Traditional identifications of prenylated proteins from complex samples are either time-consuming or ambiguous. To improve their identification in mass spectrometry (MS), a strategic method for enriching prenylated peptide is developed. We perform simple oxidation to produce a labile sulfoxide that can generate a signature fragment in collision induced dissociation (CID). This also introduces epoxy groups in the prenyl chain to increase its hydrophilicity and create enrichment opportunity for better identification. Here, we spiked a farnesyl peptide (REKKFFCAIL) in the digested peptides of bovine serum albumin. The spiked sample was reacted with meta-chloroperoxybenzoic acid, dithiothreitol and biotin-maleimide for introducing a biotin enrichment tag and enriched by avidin-biotin chromatography. Sample analysis was performed by nano-LC-MS/MS. In the MS/MS spectra analysis, two potential biotinylated peptide precursors were identified and their MS/MS spectra show high abundant signature fragment. Furthermore, the signature fragments were confirmed more confidently by MS3rd fragmentation. This fragment pattern shows that prenylated peptides were successfully enriched from complex peptide mixture. This enrichment strategy will help to understand the prenylation modification process in cells as well as identify the prenylation at large-scale using mass spectrometry.

Poster Number: 16


Identification and Characterization of Modified Disulfide Bonds using Tandem Mass Spectrometry

Presenter: Pooja Ramanuj, Chemistry and Biochemistry Graduate Student

Mentor: Dr. Saiful M. Chowdhury

Group Members: Kamal, Abu Hena Mostafa; Chakrabarty, Jayanta; Wanigasekara, Maheshika S; Shahinuzzaman, A.D.A; Fang, Zixiang;

Abstract:

Proteins are made up of different amino acids which can undergo various modification known as post-translational modifications (PTMs). Amino acids side chain is the most common site for the PTMs. There are some common PTMs like phosphorylation, glycosylation, methylation, ubiquitination, and acetylation. Cysteine side chain modification is one unique PTM which involves disulfide bond and sulfhydryl formation. Disulfide bond helps to maintain protein modifications and their structure. That's why, identification of disulfide bond is an inevitable step to get the detailed information about protein functions. Disulfide bonds are some potential targets to cure some life-threatening diseases like cancer. Previously, several methods introduced to identify disulfide bonds which requires either high quality sample or time consuming. Moreover, data software mainly designed for linear peptide which makes it difficult to use for disulfide identification. Over goal is to develop a chemistry based approach using maleimide group and identification by mass spectrometry (MS). We used dibromolaemide first to check activity of thiol reactive reagent in controlled pH environment. Then, biotin-maleimide and biotinylated dibromomalemide reagents were used for enriching the target peptides using affinity chromatography. Myoglobin spiked sample were used for the further confirmation of reactivity towards cysteine. Samples were analyzed by nano LC-MS. MS/MS study shows the high abundant peak of modified cysteine with dibromomalaemide and enriched biotinylated cysteine residue. Moreover, oxidation results show characteristic loss of RS2OH in MS/MS spectrum which gives further confirmation of disulfide bonds. This enrichment strategy will help to identify disulfide modification at large-scale using mass spectrometry.

Poster Number: 17


Functional Arginine Residues Identification Using Bio-Orthogonal Click Chemistry Couple to Mass Spectrometry

Presenter: Maheshika Wanigasekara, Chemistry and Biochemistry Graduate Student

Mentor: Saiful M Chowdhury

Abstract:

Post-translational modification (PTM) is a series of covalent translational process of protein, which are cleave of amino acid sequence and also addition or removal of chemical moieties to amino acid residues. Advances in mass spectrometry (MS) methods confidently revealed several PTMs. Arginine is one of the most common natural amino acid, that play a vital role as a recognition sites for other proteins. However, glycation is a non-enzymatic modification of proteins, which is modified by adding sugar molecules to the protein. This irreversible covalent modification occurred at amino groups by carbonyl compounds, and that are lead to form the advanced glycation end-products (AGEs).

Bradykinin, neurotensin, and substance P were used as the model peptides for this study. The reagent mixture was reacted with peptides under agitating condition at 37Â°C for 2 hr. After the reaction, samples were dried for 1 hr at 30Â°C, and then reconstituted in 0.1% FA. Afterwards, the samples were desalted and diluted with 1: 1 MeOH: H2O: 2% acetic acid solution to obtain the mass spectrum by direct infusion. Besides RNase protein also labeled with the same reactions.

Three model peptides were treated with 1, 2-cyclohexanedione azide analog (CHD azide) in NaOH. Same as those model peptides, standard protein RNase A (13.7 kDa) was reacted with CHD azide. The reactive ariginine residues containing peptides were enriched from the digested peptides of RNase using the click chemistry based enrichment approach. To identify the modification sites by the mass shift, we performed MS/MS fragmentation using nano LC-MS/MS. Modified mass was also helps to identify the complete derivatization of arginine residues by CHD azide. In this study, few modified arginine residues were found by reacting with CHD azide in RNase A protein. We believe this work will allow to map and selective enrichment of the reactive arginine residues in proteins.

Poster Number: 18


A Diagnostic Kit for The Simultaneous Determination of Benzene, Toluene, Ethylbenzene and Xylenes Biomarkers

Presenter: Yehia Baghdady, Chemistry and Biochemistry Graduate Student


Abstract:

Benzene, toluene, ethylbenzene and xylenes (BTEX) are ubiquitous toxic pollutants in our environment. Sources of exposure include both indoor and outdoor sources. Humans can be easily exposed to BTEX compounds through inhalation, skin absorption, and/ or ingestion of contaminated food and water. Due to their carcinogenic and toxic effect, the levels of their urinary metabolites are currently regulated by many organizations worldwide. These urinary metabolites are useful biomarkers as they reflect absorption by all routes (inhalation, dermal, and ingestion) and they have the advantages of long half-life, high specificity, low volatility, and non-invasive sampling of urine. We developed and optimized a liquid chromatography tandem mass spectrometric (LC-MS/MS) method for simultaneous determination of fourteen metabolites of BTEX in urine. This method adopts in situ derivatization followed by analysis on LC-MS/MS system. This will help to obtain a metabolite profile of exposed individuals using a single platform and thus can be used as a diagnostic measure for exposure to BTEX.

Poster Number: 19


Gas chromatography and metal analysis of produced water treatment with Brita filter

Presenter: Chuong Nguyen, Chemistry and Biochemistry Graduate Student

Mentor: Kevin A. Schug, Ph.D.

Group Members: Doug Carlton, Ph.D. and Tiffany Liden

Abstract:

Unconventional drilling operations, also known as hydraulic fracturing has been the main process used in creating natural gas wells in the United States. Many fracking sites are located in large cities, closed to residential areas. Sometimes, fracking well malfunctions, spilling thousands of gallons of produced waste water and pose a threat of contaminating underground or surface water reservoir. Produced water is often contaminated with a complex mixture of salts, volatile and semi-volatile organics, metals, organic acids, and particulates, as well as additives from the drilling process. In this study, we tested ability of the wastewater treatment using a household grade Brita pitcher filter which uses coconut-based activated carbon with ion exchange resin. In normal usage, a Brita filter can be used with up to 40 gallons of tap water to reduce chlorine taste and odor, zinc, and harmful contaminants copper, mercury and cadmium. Some analytical instruments used were GC-FID, GC-MS, TOC, XRF in qualitatively and quantitatively analysis. Brita filter with coconut based activated carbon was found able to reduce a range of organic and inorganic chemicals in produced water but not enough to be below safe drinking standards.

Poster Number: 20


Mass spectrometry based global profiling of N-terminal modifications in LPS-activated macrophage proteome.

Presenter: A D A Shahinuzzaman, Chemistry and Biochemistry Graduate Student

Mentor: Saiful Chowdhury

Abstract:

Macrophages are the first line of defense against pathogens. Their functions include wide range of activities including phagocytosis mediated killing of microorganisms, healing tissue injury, inflammation etc. The macrophages require to be activated for their function to be exerted. In combination of different cellular activator molecules and Lipopolysaccharides (LPS) that is found in outer layer of microorganisms, the macrophages are activated. The molecular mechanisms of activation process are yet to be fully understood. Proteins, the structural and functional units of the cell, may go through several types of modifications. N-terminal modifications are one of them and it occurs in the N-terminal residue of the protein. These modifications can include methylation, acetylation, formylation and so on. Such modifications can further direct the activation or suppression of the respective proteins or their interactive partner proteins or RNA or DNA. Our goal is to profile the N-terminal modifications in macrophage proteome. So, started in peptide level. First, we selectively react the free N-terminal amines of simple peptides (Bovine serum albumin digest) with N-succinimidyl S-acetylthioacetate (SATA) and subsequently to Hydroxylamine to convert it to a sulfahydral N-Terminal. These selectively bind to a resin (thiopyrol sepharose) and then our N-terminal modified peptides (acetylated bradykinin and Neurotensin) are negatively enriched from a pool of free N-terminal peptides. Next, we hope to apply this approach to identify the native and modified N-terminals in the N-terminal residue of macrophage proteome, before and upon activation. So, having a better understanding on macrophage activation will help design better drug targets.

Poster Number: 21


Probing the active site of F420-dependent Glucose-6-Phosphate Dehydrogenase using steady-state and pre steady-state kinetic analysis

Presenter: Lindsay Davis, Chemistry and Biochemistry Graduate Student

Mentor: Dr. Kayunta Johnson-Winters

Group Members: Lindsay Davis, Mercy A. Oyugi, Ghader Bashiri, Edward N. Baker and Kayunta Johnson-Winters

Abstract:

F420-dependent Glucose-6-Phosphate Dehydrogenase (FGD) is an essential enzyme found with Mycobacteria tuberculosis, the causative agent of TB disease. FGD catalyzes the conversion of Glucose-6-Phosphate (G6P) to 6-Phosphogluconolactone, using a unique cofactor known as F420. This reaction is carried out as the first step of the Pentose Phosphate Pathway, which is important for nucleic acid biosynthesis. A previous crystal structure of wild-type FGD led to a proposed mechanism, suggesting that the active site residue His40 serves as the active site base, while Glu109 serves as the acid. Our recent work has suggested that Glu109 is the active site acid. However, His40 does not serve as the base. The goal of this present work is to determine which amino acid (Arg283, Lys259 or His260) could possibly serve as the active site base, using steady state and pre-steady state kinetic experiments as well as binding.

Poster Number: 22


Investigating the role of R186 in the subunit communication of F420H2:NADP+ oxidoreductase using steady-state and pre steady-state kinetics

Presenter: Denzel Pugh, Chemistry and Biochemistry Graduate Student

Mentor: Kayunta Johnson-Winters

Group Members: Dr. Cuong Q. Le and Dr. Kayunta Johnson-Winters

Abstract:

Life has evolved to use NADPH as a biological fuel, which transiently stores the reducing equivalents needed to drive numerous essential redox processes. These include the fixation of CO2 into carbohydrates in photosynthesis, which provides a means to store reducing equivalents for long term use, or into the evolution of methane for organisms needing to dispose of excess reducing equivalents into the environment. Methanogens is a class of the latter and play a critical role in carbon cycling, catalyzing the production of methane through the reduction of carbon dioxide. F420H2:NADP+ oxidoreductase (Fno) is an enzyme prevalent in methane producing and sulfate producing organisms. Fno catalyzes the production of NADPH within the cell, using the F420 cofactor. NADPH production with methanogenic organisms is linked to glycolysis and F420 cofactor production and therefore, highly regulated. Our previous work on Fno has determined that the enzyme is a dynamic homodimer that is regulatory because it participates in negative cooperativity kinetics and half site reactivity. The aim of this research is to understand subunit communication within Fno by studying the functionality of specific amino acid residues that are located at the interface of the two subunits using binding, steady-state and pre-steady state kinetic methods.

Poster Number: 23


Continental hydroclimate during the late Paleocene-early Eocene greenhouse condition in the Greater Green River Basin, SW Wyoming, U.S.A.

Presenter: Min Gao, Earth and Environmental Science Graduate Student

Mentor: Majie Fan

Group Members:

Abstract:

Understanding of continental climate characteristics during warm periods in geologic past can shed lights on future climate and environment when Earthâ€™s atmospheric CO2 concentration (pCO2) increases significantly by fossil fuels burning. Last greenhouse condition on the Earth happened during the late Paleocene to early Eocene (LPEE, ~59-52 million years ago). The warm period was well expressed in high-resolution benthic foraminifera oxygen isotope record, showing a 4-6 Â°C increase in ocean bottom temperature (Zachos et al., 2001). Despite the fact that rich amount of paleoclimate data have been produced recently from continental records, the responses of continental climate and environment to the global warming during the LPEE remain poorly understood, in part, due to the lack of high-resolution, continuous record in continental interiors. In this study, we build a high-resolution, continuous bulk organic carbon isotope record documenting early Paleogene (~65-53 million years ago) continental climate in the Greater Green River Basin, southwestern Wyoming. In addition, we reconstruct the pCO2 during this warm period using carbon isotope compositions in paleosol carbonates. Our preliminary results show that the carbon isotope ratio dropped up to 4 â€° during the LPEE, consistent with previous marine and continental records. Our reconstructed pCO2 during the earliest Eocene (~55-53 million years ago) is 600-1200 ppm, which is 2-3 times higher than today and implies the temperature was warmer than today. Mean annual precipitation will be estimated using the chemical index of alteration without potassium to test whether continental climate was wetter or drier during the warm periods.

Poster Number: 24


Lake pollution stratigraphy through SEM-XRF studies: Case study of Halton, NW England

Presenter: Upasana Dhar, Earth and Environmental Science Graduate Student

Mentor: Dr. Andrew Hunt

Abstract:

Lakes are considered important archives of sedimentological, environmental and neotectonic changes. The sediment record of lakes documents local landscape history of an area changing through time and anthropogenic impact on environment. As useful receptors of products in the environment, they can be used to reconstruct the history of the local environment or to derive pollution patterns extending back in time, extending the reach of technologies of monitoring ambient air quality (see e.g., Power and Worsley.,2009). Such analysis if extrapolated can guide future decisions in making the environment sustainable. Health implications of long-term exposure to pollutants is an increasing concern for areas where large-scale industrial activity occurs (Sainsbury et al.,1996;Staples et al.,2003).

Composition, size and structure of the particle pollutants play an important role in determining the health risk for humans and ecosystems.Concentration of particulates in stratigraphic record, have also gained significant interest to identify the geological marker for a new epoch, the Anthropocene (Oldfield et al.,2014). The study sites (urban ponds) are located near Halton,NW England, well known for its chemical industry since early 1800â€™s. Urban ponds can provide historical atmospheric fallout records of the complex particulate matter (PM emissions) experienced in those areas. Sediment cores from 3 lakes near Halton are studied. The focus is lake sediment analysis-structure and composition, through its chemical composition analysis by SEM- XRF techniques. We present some initial data from two significant depths a) 0-1 cm depth (recent sediments) and b) approx.20 cm depth (earlier sediments) which are divided into different size fractions and analysed through SEM-XRF. Change in concentration of metals and non-anthropogenic particles are grouped based on concentration and size. How concentration varys with depth, hence time is our interest to understand the impact of industrial activity (since the start of the industrial revolution) on air and water quality. Samples are analysed for concentrations of toxic and trace elements like Pb, Cd, Sn, S, industrial minerals like Cu, Zn, Sn, Ti and normal crustal (major) elements like Al, Si, Fe.It is interpreted that industrial and anthropogenic activities led to increased pollution trends and deposition of toxic metals, to a large extent if not all, which pose risk to health by inhalation of particles or by absorption through skin.

Poster Number: 25


The Chemical Distribution of Major and Trace Elements in Microbially Mediated Carbonate Travertine from Honey Creek, an Aquifer Spring-Fed Stream in the Arbuckle Mountains of Southcentral Oklahoma

Presenter: Emmanuel Higa, Earth and Environmental Science Graduate Student

Mentor: Matthew Loocke

Group Members: Elizabeth Griffith

Abstract:

Travertine is a form of calcium carbonate that occurs in stream systems fed by carbonate hosted aquifers. Travertine formation in these systems is often mediated by microbial activity which occurs on near their surfaces and tend to display seasonal laminations of alternating dark micritic and lighter sparry carbonate. Two distinct forms of travertine have been found to occur at Honey Creek, an aquifer spring-fed stream in the Arbuckle Mountains of south-central Oklahoma. Denser, laminated precipitates occur in faster moving portions of the creek, while encrustations that bear a close association with organic material occur in slower moving portions of the stream. The chemical distribution of elements throughout microbially mediated carbonate is thought to be influenced by seasonal controls on the geochemistry of water and environmental conditions found in the system. The rapid travertine precipitation rates (up to mm/ year) and progressive carbon dioxide (CO2) degassing of spring-water as it flows along Honey Creek provide a natural laboratory in which to study the evolution of water in spring systems and explore the partitioning of chemical components between water and travertine. The response of carbonate stable isotope and major/minor elemental ratios in to environmental conditions has been parameterized by laboratory experiments and led to their wide use as paleoenvironmental proxies. Diffusive effects on elemental and isotopic compositions are often observed in marine carbonate sediments, which are influenced by equilibrium controls on precipitation and dissolution rates. The rapid precipitation rates and seasonal nature of laminations in the HC travertines provides a unique opportunity to study the micro-distribution of elements across an entire specimen. Thin sections of solid samples will be prepared and analyzed using wavelength-dispersive x-ray fluorescence (WD-XRF) to determine their bulk chemical composition and the distribution of major and trace elements between seasonal laminations will be mapped using an electron probe microanalyzer (EPMA). The results will be used to determine how elements partition in response to changing environmental conditions and whether they can diffuse between laminations. These analyses will help in determining (i) whether the terrestrial carbonate record can be applied to paleoenvironmental reconstructions and (ii) how much of an impact microorganisms play in the partitioning of elements in bio-mediated carbonate.

Poster Number: 26


Tracing Paleozoic Sediment Dispersal of the Fort Worth Basin in the Southern Margin of Laurentia

Presenter: Ohood Alsalem, Earth and Environmental Science Graduate Student

Mentor: Majie Fan

Group Members: Majie Fan, Juan Zamora, Xiangyang Xie, and William R. Griffin

Abstract:

We date zircon minerals in the sedimentary rocks that deposited during 500-300 million years (myr) ago in the Fort Worth basin in north-central Texas in order to track the sources of these grains, and reconstruct paleodrainage patterns in the southern North America continent. A total of 1002 zircon ages were collected from two sandstone samples of ~500 myr old and six sandstone samples of ~300 myr old. About 90% of the zircons in the two samples of ~500 myr old are of 1.451-1.325 billion years (Ga) old. These zircons were delivered by a local river draining a magmatic province located in the mid-continental area of the North America continent. The six samples of ~300 myr old have ~47% of zircons of 1.300-0.900 Ga old, which were derived from the Appalachian highlands located today in the eastern United States. These six samples also have ~16% of zircons of 650-550 Ma, which were transported from the Gondwana continent when it collided with the North America continent. Our results show a clear change in river drainage pattern during 500-300 myr ago in the southern North America continent.

Poster Number: 27


Geochemical and Geochronological Analysis of the Cenomanian-Turonian Extinction Event in the Eagle Ford Shale of South Texas

Presenter: Daniel Valencia, Earth and Environmental Science Graduate Student

Mentor: Matthew Loocke

Group Members: Asish Basu

Abstract:

The Eagle Ford Shale Play has proven to be a prolific unconventional oil and gas play ever since the first well was drilled in 2008. Unconventional plays differ from conventional plays in that the reservoir is also the source rock where the hydrocarbons are generated. The Eagle Ford source rock has been an economically viable producer of oil and gas largely in part to the relatively recent advances in hydraulic fracturing and horizontal drilling technologies made by American oil companies. These technologies make it possible to target formations tens of thousands of feet below the surface and produce hydrocarbons at competitive prices relative to conventional plays. In order to maintain this competitive edge with the industry and apply these technologies to other unconventional reservoirs, it is vital that we identify what, if any factors control the geochemistry and hydrocarbon generation in restricted basins of similar type. Through high resolution analyses of cores retrieved from the Eagle Ford, we hope to identify geochemical markers that will aid in identification of similar plays throughout the area that was once the Western Interior Seaway(WIS). The Eagle Ford Shale is part of a series of Late Cretaceous sediments deposited in a shallow marine setting during 7Ma time frame. During this time interval, the WIS flooded the interior of North America and effectively split it into two landmasses was able to record a global anoxic extinction level event known as the Cenomanian-Turonian oceanic anoxic event (OAE2). OAE2 occurred approximately 91.5 +-8.6 Ma and restricted the global ocean oxygen supply for nearly half a million years, causing the extinction of ~27% of marine vertebrates. These types of conditions provided to be ideal for the generation, accumulation and thermal maturation of vast amounts of hydrocarbons, of which the Eagle Ford shale hosts and produces almost 100Ma later. High resolution geochemical sample analyses will be conducted and sponsored by the Shimadzu Center, in order to measure the concentrations of major, minor and trace elements as well as total orgainc carbon (TOC). This data aids in inferring paleodepositional conditions, possible causes of the global anoxic event and the high rates of organic carbon burial. Preliminary results suggest a possible influx of volcanic activity during this period, which could possibly be the the catalyst to the largest reservoir of hydrocarbons the Eagle Ford Shale Play has provided us today.

Poster Number: 28


Modeling the effects of the immune system on the fracture healing process

Presenter: Imelda Trejo, Mathematics Graduate Student

Mentor: Hristo Kojouharov

Abstract:

Immune system cells play a key role in the fracture healing process. At the early stage of the process, they clean up the injury site, control the inflammation and enhance bone reconstruction. Moreover, immune cells release pro-inflammatory molecules that promote the osteogenic activities. However, the mechanisms and functions of immune cells present at the fracture site are not clearly understood. In this work, we present a mathematical model for the bone healing process incorporating both immune and bone cells. Our model consists of a system of nonlinear ordinary differential equations which represents the interactions among the macrophages, mesenchymal stem cells, chondrocytes and osteoblast cells in the bone healing process. The interaction among those cells is governed by cytokines and growth factors. We use the model to simulate the progression of healing for different types of fractures. A set of numerical simulations is also presented to examine the effect of inflammatory molecules on the outcome of bone repair. Our mathematical model reproduces an accurate bone healing time under a health body conditions, according to the statistical data. This model also captures delayed wound healing.

Poster Number: 29


Prospects for dynamically formed Binary BHs from GCs in the Local Universe

Presenter: Domi Jin, Physics Graduate Student

Mentor: Matthew Benacquista

Abstract:

The dynamical evolution of globular clusters is expected to produce stellar mass binary black holes with higher total mass than found in the field population of binary black holes. Such systems are identified as gravitational wave sources with the recent detection made by LIGO. We use the Monte Carlo code MOCCA to simulate the production of binary black holes from globular clusters. These compact binary systems are found to be ejected quickly from the host globular cluster. Thereafter, they evolve independently in the form of gravitational radiation. We model the population of globular clusters out to 30 Mpc. We discuss here the prospects for detecting dynamically formed binary black holes at extragalactic distances using space-borne gravitational wave detectors.

Poster Number: 30


Multi-View Scatter Correction for Cone-Beam Computed Tomography

Presenter: Cong Zhao, Physics Graduate Student

Mentor: Mingwu Jin

Abstract:

Scatter contamination is one of the main sources of decreasing the image quality in cone-beam computed tomography (CBCT), which is widely used in radiation treatment of cancer. The moving blocker method is economic and effective for scatter correction (SC). The blocker edge detection is foremost important because the signal in the blocked region is assumed as scatter signal and that in the unblocked region is assumed as the sum of scatter and primary signal. However, blocker edge detection is challenging for large-object imaging and the detection error can significantly deteriorate both primary signal and scatter signal estimation and lead to unacceptable reconstruction results.

In this study, we propose to use the adjacent multi-view projection images to jointly estimate scatter signal directly without blocker edge detection. In return, the more accurately estimated scatter signal can be utilized as an adaptive threshold to detect blocker edges more accurately for greatly improved robustness of moving-blocker based SC.

The experimental results using an anthropomorphic pelvis phantom CBCT data show that the new method can effectively eliminate the blocker detection errors and the reconstruction image achieved a 120% improvement on reconstruction accuracy. This development will expand the utility of moving-blocker based SC for large-object imaging and provide the needed robustness for its clinical translation.

Poster Number: 31


Factors that influence performance in physics

Presenter: Michael Greene, Physics Graduate Student

Mentor: Ramon Lopez

Abstract:

Several performance-related data were collected from PHYS 1443, which is a calculus-based physics course taken by predominantly science and engineering students, over the course of three semesters. Sources of data include in-class assessments, self-reported surveys, and information from transcripts. We used linear correlation models using this data and students' final grades to show an agreement with existing research linking mathematical ability with performance in physics. We also identified other factors which correlate to performance in the course.

Poster Number: 32


FINDING STABLE CRYSTAL STRUCTURE AND THEIR ELECTRONIC PROPERTIES OF SI-RICH SILICON CARBIDE BY FIRST PRINCIPLE CALCULATION

Presenter: Noura Dawas Alkhladi, Physics Graduate Student

Mentor: Dr. Muhammad N. Huda

Abstract:

Silicon carbide has become an attractive semiconductor material with its high stability. It has been used in variety of fundamental aspects and applications such as photovoltaic solar cells due to its unique properties, for instances high thermal conductivity and low density. Investigating appropriate silicon rich silicon carbide structures which are thermodynamically stable as well as can be used in applications without requiring a pure grade of Silicon or pure grade of silicon carbide. Density functional theory (DFT) calculations were used to examine the stability of various structures of silicon carbide such as 2H-SiC, 4H-SiC, 6H-SiC, wurtzite structure, and Diamond structure of SiC. We investigated different configurations of silicon and carbon atoms in these silicon carbide structures to obtain more stable results. We have studied the electronic structures of these structures of silicon rich silicon carbide. We have replaced carbon atoms by Silicon atoms because the carbon atoms considered to be one of impurities that silicon has. Total energies of several structures, as well as their formation energies, have been calculated by density functional theory.

Poster Number: 33


Monte Carlo simulation of Carbon Ion Therapy

Presenter: Ananta Raj Chalise, Physics Graduate Student

Mentor: Dr. Mingwu Jin

Abstract:

The high Relative Biological Effect (RBE), narrow Bragg peak, less severe fragmentation tails, low entry RBE and low oxygen enhancement ratio make carbon ion therapy an attractive treatment option for deep seated and hypoxic radiation resistant cancers, as shown by the primary data from a number of heavy ion therapy centers in Japan and Europe. Due to high energy of the treatment beam, online range verification and dose monitoring is vitally important to achieve an effective treatment while maintaining the safety for patients.

In this work, we investigated carbon ion therapy using Monte Carlo simulation techniques. Specifically, we used GEometry ANd Tracking - 4 (GEANT4) Monte Carlo package to study interactions of carbon ions at different energy levels (100 â€“ 430 MeV per unified atomic mass) in a water phantom, mimicking the human soft tissues. Both dose distribution and prompt gamma photon profiles were acquired from simulation in order to deduce their relationship.

Our results show that GEANT4 simulation accurately predicts the depth dose profile (for instance 20.3 cm for 330 MeV/u) of the carbon ion in a uniform medium. The prompt gamma photon profiles are correlated with the dose profiles, which could provide a means for online dose monitoring.

Poster Number: 34


Stability enhancement of solar absorber material Cu2S by alloying with Ag

Presenter: Sajib Barman, Physics Graduate Student

Mentor: Dr. Muhammad Huda

Abstract:

Cu2S is an important solar absorber material and has great prospect in the field of renewable energy. However, this material suffers from instability due to spontaneous Cu vacancy formation and Cu diffusion in the structure. The spontaneous Cu vacancy causes the material to possess high p-type doping, which leads the material to behave as a degenerate semiconductor. This is a vital obstacle for this material to be used as an effective solar absorber material. A relatively new predicted phase of Cu2S which has an acanthite-like structure was found to be more preferable than the well-known low chalcocite Cu2S. However the Cu-vacancy formation tendency in this phase remained similar. We have found that alloying silver with this structure can help to reduce Cu vacancy formation tendency without altering its electronic property. The band gap of silver alloyed structure is higher than pristine acanthite Cu2S. In addition, Cu diffusion in the structure can be reduced with Ag doped in interstitial sites. Here, we present a systematic approach within the density functional theory framework to study Cu vacancy formation tendency and diffusion in silver alloyed acanthite Cu2S, and proposed a possible route to stabilize Cu2S against Cu vacancy formations by alloying it with Ag.

Poster Number: 35


Niobium (Nb) doping on bismuth vanadate (BiVO4) photocatalyst for photocurrent improvisation

Presenter: Hori Pada Sarker, Physics Graduate Student


Abstract:

For any solar conversion process, a suitable absorber material is necessary to make the conversion process efficient. Given the present state of global warming due to the greenhouse effect and a gloomy view of the future availability of fossil fuels, it has been a frantic search in recent decades to find such "suitable" materials. Bismuth vanadate (BiVO4) is a good candidate as a photocatalyst for hydrogen evolution via water splitting to produce hydrogen fuel cell. It has a suitable band gap and moderate band alignment with respect to water redox potential for water splitting. The conduction band minima of BiVO4 is mostly composed of V â€“ 3d bands which are very localized. This localization nature of V â€“ 3d conduction bands makes the charge carriers (electron and hole) transport complex within bismuth vanadate. In this present study, density functional theory (DFT) with generalized gradient approximation (GGA) as exchange correlation functional has been used to study the Nb incorporation on both cationic sites of BiVO4 with and without oxygen vacancy. It shows that Nb incorporation on both cationic site replaces the V â€“ 3d localized band by the less localized Nb â€“ 4d bands. Nb doping in BiVO4 also creates a shallow donor level, which is beneficial for charge carrier transport. Thereby, incorporation of Nb in BiVO4 photocatalyst could help to improve the photocurrent. The solubility of Nb in BiVO4 has also been studied and it shows high solubility of Nb in BiVO4 with both oxygen rich and poor growth condition. Finally, the single phase stability of BiVO4 via the chemical potential landscape analysis will be presented.

Poster Number: 36


Overcoming the challenges of storing plutonium oxides.

Presenter: Shafaq Amdani Moten, Physics Graduate Student

Mentor: Dr. Muhammad Huda

Abstract:

Plutonium, a radioactive material with applications in nuclear fuels, is stored as plutonium oxide power with PuO2 being the most stable form. Stored in steel canisters, these materials have long half-lives and emit alpha particles. In number of cases, it has been observed that the canisters have malfunctioned over a period of time in various storing facilities. This poses a great hazard to the environment. Since the "Pure" stored samples include about 3%-8% of impurities, it is important to understand the interaction of these impurities within the bulk PuO2. Our study explores the interaction of the most likely of metal impurities within PuO2. Using Density Functional Theory (DFT), we calculated a substituted metal impurity in 2x2x2 PuO2 supercell. We also calculated the effect of the impurity around an oxygen vacancy. An impurity can affect the band structure and the subsequent behavior of the system. Our results reveal interesting volume contraction of PuO2 supercell when one plutonium atom is substituted with a metal atom.

Poster Number: 37


Solar Wind Fluctuation Effects on the Viscous Interaction Using LFM

Presenter: Richard Bonde, Physics Graduate Student

Mentor: Ramon Lopez

Abstract:

Observations of the value of the transpolar potential as a function of the interplanetary magnetic field (IMF) show a nonzero intercept. This residual potential in the absence of merging with the IMF is attributed to a mechanical interaction with the solar wind. Global MHD simulations also develop a residual value of the transpolar potential and exhibit magnetospheric convection when the IMF is zero. This residual value is known as the viscous potential, and it is dependent on solar wind speed and density. In this study, we examine the effect of solar wind velocity fluctuations along the Y and Z axes on the viscous potential. Velocity fluctuations in the Z-direction appear to have significant effects on the viscous potential, whereas velocity in the Y-direction appear to have little or no effect. I will discuss the variation in any effect on the viscous potential as a function of the period and amplitude of the solar wind velocity fluctuations.

Poster Number: 38


Weakening of Si-Si Bonding in Si60 Nanoclusters under Exohydrogenation

Presenter: Edan Bainglass, Physics Graduate Student


Group Members: Shafaq A. Moten, Sajib K. Barman, Hori Pada Sarker, Noura D.M. Alkhaldi

Abstract:

Nanoscale materials allow for fine tuning of electronic properties, which is paramount to the predominantly Silicon-based electronic industry. Exohydrogenation, a process in which Hydrogen is used to terminate the surface of nanoscale materials, is generally considered favorable in terms of lowering the electronic energy of the system, thus providing a mechanism for stabilizing nanoclusters. In the current study, we performed density functional theory (DFT) analyses of several Si_60 nanoclusters in attempt to determine the effects of exohydrogenation on the internal Si-Si bonding network. Results show that upon surface passivation, a substantial weakening of the Si-Si bond strength occurs. We present the case of the Si_60 fullerene geometry, in which passivation results in the largest magnitude of Si-Si bond weakening, leading to the structure favoring an unpassivated ground state. We determined that the lack of fully-coordinated Si-Si bonds within the cluster contributes to its inability to balance the weakening effect with the benefit of exohydrogenation. This suggests that the Si_60 fullerene may be stabilized by adding an internal support system. Among those Si_60 nanoclusters favoring passivation, the most stable structures were found to consist of a network of Si_n units, with a geometry of a slightly bent chain of three Si_20 units exhibiting the highest stability under passivation.

Poster Number: 39


Perceptions of Crowding and Gym Equipment Use

Presenter: Shane Snyder, Psychology Graduate Student

Mentor: Dr. Angela Liegey-Dougall

Group Members: Cory Newell

Abstract:

Problem. Crowding has been defined as the psychological condition that derives from oneâ€™s perception of a dense environment or amount of social stimulation in their proximity (Desor, 1972). Few research studies have been conducted on crowding perceptions in fitness centers/gyms. Specifically, if density (the number of people at the gym) moderates the effects of crowding perceptions of specific areas (cardio, free weights, and circuit weights) on equipment use. Because previous research has shown that attributions of perceived crowding can be experimentally manipulated in low and high density gym areas (Jenney, 2015), the purpose of the current study was to further understand underlying processes of crowding in fitness centers and how these processes relate to frequency of use of equipment. Method. The current study used a cross-sectional design and recruited college fitness center users (N = 152) at the beginning of a spring semester. This study measured demographics (gender, BMI, age), social crowding, density (crowded vs. non-crowded times), and equipment use. Multiple regression models were conducted to examine the influence of crowding perceptions on gym equipment (free weights, circuit weights, and cardio equipment). Results. As expected, density moderated perceptions of crowding and use of equipment in the free weights area, b = -1.32, SE = 0.61, t(82) = -2.17 , p = .03. Specifically, for people who came during high density times, greater perceptions of social crowding in the weights area predicted greater use of free weights, b = 0.55, SE = 0.27, t(82) = 2.08, p = .04, but social crowding was not associated with use among people who came during low density times, p = .17. Contrary to expectations, density and social crowding perceptions did not predict circuit weight use. Even though density only marginally moderated social crowding perceptions and greater use of cardio equipment, p =.10, during high density times, more social crowding in the cardio room predicted greater use of cardio gym equipment, b = .57, SE = .16, t(92) = 3.49, p = .001. Conclusions. These findings suggest that perceived social crowding in the gym may positively impact individual exercise use, but only during high density times and in certain areas. Further research needs to be done to understand the mechanisms of these effects and to determine if there are ways in which fitness centers can manipulate perceptions of crowding to increase use.

Poster Number: 40


Validating the Worthy Leadership Model Against Existing Measures of Workplace Culture and Engagement

Presenter: Zachary Warman, Psychology Graduate Student

Mentor: Dr. Kelsey Medeiros

Group Members: Dr. Aaron Friedman and Dr. Chris Coultas

Abstract:

Previous research has indicated that the Worthy Leadership Model (Thompson, Grahek, Phillips, & Wade, 2008) stands as a validated means of assessing leadership ability. While used in a developmental or selection role, no previous attempts have been made to validate the model against measures of organizational culture. The present effort aims to examine where the Worthy Leadership Model's core behaviors converge or diverge from the Langford (2008) Voice Climate Survey and Shaufeli et al. (2011) workplace engagement measure. Other areas of examination include how organizational culture and leader perceptions may relate to perceptions of corporate social responsibility and personality. This study will utilize correlations to examine where Worthy Leadership Model factors (e.g., Commitment to Learning & Personal Growth) converge or diverge with subscales of Langford (2008) and Schaufeli et al. (2011) measures. The results of this study could support the usage of the Worthy Leadership Model in alternative areas than leadership selection and development. Support for the Worthy Leadership Model would also expand potential services which Leadership Worth Following, LLC., a management consulting firm in Irving, Texas, could offer to potential clients.

Poster Number: 41


The Antibacterial Activity of Salicylic Acid and its Polymers

Presenter: Jaclyn Bazaldua, Biology Undergraduate Student

Mentor: Michael Roner

Group Members: Lindsey Miller

Abstract:

The latest significant antibiotic was developed three decades ago. Research fields have begun to combat antibiotic resistance by looking for novel antibiotics from unfamiliar fields. Six compounds were tested to address the lack of antibiotics: one organotin, salicylic acid, and five salicylic organotin polymers. Organotins have been shown to inhibit the growth of bacteria, but the mechanisms are unclear. Using a broth microdilution assay, the compounds were tested against ten different bacteria, eight of which were gram-negative. The assay was tested using four different concentrations per compound, giving more in depth results. The highest inhibition of bacteria bacterial growth using the microdilution assay for all the compounds, occurred at a concentration of 5 Âµg/ml.

Poster Number: 42


Investigating the Effect of Symbiont Variation and Immune Challenge on Host Immunity in the Caribbean Coral, Orbicella faveolata.

Presenter: Caleb Butler, Biology Undergraduate Student

Mentor: Laura Mydlarz

Group Members: Lauren Fuess

Abstract:

Coral reefs are crucial ecosystems for marine biodiversity and coastal storm protection. In recent years, it had become evident that coral reefs are in danger due to increases in sea surface temperature and the frequency of marine disease outbreaks. Host corals have co-evolved a mutualistic relationship with an dinoflagellate algae, Symbiodinium. However, while it is clear that corals are dependent on their symbionts to meet their nutritional requirements, many aspects of this relationship are poorly understood. Interestingly, studies have indicated that symbionts may potentially suppress coral immunity in order to facilitate symbiosis. To better understand this potential trade-off, we examined the relationship between symbiodinium density and the coral immune response. In this experiment, symbiont density of corals of the Orbicella faveolata was manipulated and cores were subsequently treated with an immune challenge with lipopolysaccharides. Additionally, a second treatment was executed blocking the potential pathways (TGF-beta) which symbionts use to suppress host immunity was executed. Immune assays were then used to examine levels of various types of host immunity in the three groups of corals. Through this experiment we learned that blocking the TGF-beta pathway increased coral immune response and decreased antioxidant production. As expected, the Symbiodinium levels had a positive correlation with antioxidants and a negative correlation with antimicrobial activity. This experiment helped expand the understanding of the mutualistic relationships between Symbiodinium and their host corals.

Poster Number: 43


It's getting hot in here : temperature's effect on the lectin profile of Symbiodinium

Presenter: Leia Klinger, Biology Undergraduate Student

Mentor: Laura Mydlarz

Group Members: Contessa Ricci

Abstract:

Symbiodinium and their coral host have a well documented, mutually beneficial relationship. A unicellular algae living within the coral cell, Symbiodinium provide their host with sugars produced through photosynthesis. In return, the coral provides Symbiodinium with waste products. The symbiosis is sensitive to environmental stressors such as elevated ocean temperatures; in severe cases coral may eject symbiodinium causing coral bleaching. Thus, Host-symbiodinium recognition is a crucial component to understanding and tackling this issue. A cell surface proteome, achieved under ambient temperature and experimentally raised temperature conditions, acquired through use of LC-MS/MS. The resulting proteome was bioinformatically data-mined with representative sequence profiles to identify potential lectins present on the Symbiodinium cell surface. Lectins are sugar-binding proteins known to play a role in host-microbe recognition. Differences in the lectin profile of Symbiodinium exposed to ambient temperatures and raised temperatures will be presented.

Poster Number: 44


Effects of the copper tolerance protein on symbiotic nitrogen-fixing bacteria Bradyrhizobium japonicum

Presenter: Christina Koo, Biology Undergraduate Student

Mentor: Woo-Suk Chang

Group Members: Dylan Parks, Hae-In Lee, Sarbjeet Niraula, Ishanka Hemachandra, Amanda Plein, Arunika Oyshi, Mouhamed Gueye

Abstract:

Bradyrhizobium japonicum strain USDA110 is a nitrogen-fixing bacterium which forms a symbiotic relationship with leguminous soybean plants Glycine max, converting atmospheric nitrogen into ammonia. The process of nodulation involves signaling components from the plant and activation of genes which promote nodule formation. Soybean lectin, a carbohydrate-binding protein, may be a crucial component in nodulation. In previous DNA microarray studies, the copper tolerance protein, bll2211 (copB), was differentially expressed when exposed to soybean lectin. Thus, we hypothesize copB plays a role in nodule formation in the presence of heavy metal stress. In this study, the role of environmental copper exposure was investigated to understand its role in growth and nodulation of B. japonicum. The gene bll2211, encoding a copper tolerance protein, was mutagenized via double-homologous recombination. We examined this gene by construction of a growth curve and a pouch experiment at various concentrations of copper for B. japonicum and its mutant âˆ†copB through comparison of the symbiotic phenotype in G. max plants. The results of this study showed there was less growth, nodule formation, and nitrogen-fixation in the mutant strain than the wild type at higher concentrations of copper. This indicated that copB may play a role in nodulation between B. japonicum and soybean plants in heavy metal stress. A better understanding of this symbiotic gene could allow for better optimization of biological nitrogen fixation for more efficient agricultural practices.

Poster Number: 45


Structure-Function analysis of zinc knuckle like CCHC motif of the R2 element

Presenter: Eyad Shihabeddin, Biology Undergraduate Student

Mentor: Dr. Shawn Christensen

Abstract:

Transposable Elements are virus like genomic parasites that replicate within host genome and are important drivers of host genome evolution. Long Interspersed Nuclear Elements (LINEs) are a major class of transposable elements. LINE replication and associated activities are responsible for the bulk of many eukaryotic genomes. LINEs replicate through a partially understood process termed Target-Primed Reverse Transcription (TPRT). Understanding the structure and function of LINE encoded protein(s) provides insight into the insertion mechanism and genomic consequence of element replication.

R2 is a site-specific LINE that codes for single multifunctional protein with DNA binding domains, RNA binding domains, reverse transcriptase, and endonuclease domains. All LINE elements also encode a zinc knuckle like CCHC motif of unknown function. Iâ€™m studying the zinc knuckle like motif of the R2 element.

Site-directed mutagenesis was performed to produce point mutations within the zinc knuckle like motif. The mutant proteins were expressed in bacteria, purified, and tested for protein-nucleic acid complex formation, DNA binding, and DNA cleavage activities using R2 protein bound to target DNA and assayed by polyacrylamide Electrophoretic Mobility Shift Assays (EMSA) and denaturing gel electrophoresis. Experiments show the mutants exhibit decreased endonuclease activity and change in protein-DNA-RNA complex conformation. DNA footprinting, RNA binding, and protein structure experiments will be used in the future to explore the nature of the protein-DNA-RNA complex conformational change. Currently, results are consistent with either a reduced ability to bind to RNA or a reduced ability to engage in protein conformational changes required for the integration complex.

Poster Number: 46


Nanomaterial-Assisted Laser Desorption Ionization for Mass Spectrometry-Based Detection of Street Drugs on Fingertips

Presenter: Jessica Lilley, Chemistry and Biochemistry Undergraduate Student

Mentor: Vladimir Havlicek

Abstract:

As drug possession and manufacturing arrests continue to skyrocket within industrialized countries, law enforcement agencies need access to a simple, efficient, and accurate method of accessing guilt to aid in the backlog many agencies are facing in the judicial system. Mass Spectrometry (MS) is a commonly used technique to measure the characteristics of individual molecules that can lead to a precise identification of the compound of interest. Compared with classical matrix-assisted laser-desorption ionization (MALDI) MS, strategies based on nanomaterial-assisted laser desorption-ionization (NALDI) MS generate a clean background, without noise or interference from an applied matrix, which is beneficial for the analysis of small molecules, such as street drugs. Using the street drugs Flephedrone (4-FMC), 3-Fluoromethcathinone (3-FMC), Pentedrone, and 4-Methylethcathinone (4-MEC), provided by Czech Republicâ€™s custom officials, several spectra were accumulated at varying drug concentrations. Unexpected points of oxidation with high intensity were present in NALDI MS and were confirmed through subsequent experiments of the same sample with MALDI MS and was proven to be applicable mass/charge (m/z) ratio to identify the drug through fingerprint scans at a concentration of 100 ÂµM. The molecular structure of the unknown oxidation points was theorized for 4-MEC through the use of collision induced dissociation (CID) and elemental analysis. The mechanism is theorized to follow an enamine reaction to reach its correct molecular weight and elemental composition. In future works, the mechanism will be confirmed with further analysis for all the street drugs. Thus, the understanding of the typical peaks produced within NALDI MS could be used by law enforcement personnel to confirm drug abusers of having come into contact with the suspected drug by use of fingerprint scans at time of apprehension which can aid in reducing the work of lab officials.

Poster Number: 47


Synthesis of Non-toxic, Inorganic Pigment ARE2S4 (A= Ca, Sr, Ba; RE= Ce, Pr)

Presenter: Melissa Orr, Chemistry and Biochemistry Undergraduate Student

Mentor: Dr. Robin Macaluso

Group Members: Paola Sotelo

Abstract:

Due to federal regulatory legislation, it is important to find new non-toxic pigments to be used in plastics, paints, and ceramics. Rare-earth sulfides have been widely used as pigments, however, their synthesis presents challenges for large scale implementation. This work examines ARE2S4 (A= Ca, Sr, Ba; RE= La, Ce, Pr) as promising pigment materials and presents a safer, more simple synthesis route. Crystal structure and physical properties are determined from powder X-ray diffraction, scanning electron microscopy, and diffuse reflectance spectroscopy experiments.

Poster Number: 48


Matrix-assisted laser desorption/ionization â€“ mass spectrometry for the characterization of groundwater microbiome

Presenter: Misty Martin, Chemistry and Biochemistry Undergraduate Student

Mentor: Kevin Schug

Group Members: Ines Santos, Doug Carlton, Jr., Zacariah L. Hildenbrand

Abstract:

Groundwater serves as the main drinking water source for over 50% of the American population. The introduction of environmental stressors into groundwater, such as unconventional gas drilling (UD) contamination, can contribute to the evolution and adaptation of pathogenic microorganisms present in groundwater. The presence of pathogenic bacteria poses as a health concern as groundwater provides a method of dissemination for antibiotic-resistant microorganisms, which can continue to proliferate even after water treatment. Therefore, it is essential to assess the groundwater microbiome and the presence of pathogenic bacteria, which may stem from the environmental contamination. Typically, molecular techniques are used to characterize microbial ecology, but can be quite expensive and time-consuming. Matrix-assisted laser desorption/ionization (MALDI) time-of-flight mass spectrometry (TOF MS) has proved to be a significant alternative to these techniques as it allows for a more rapid and cost-efficient identification of microorganisms. In this work, the groundwater microbiome was assessed in groundwater contaminated with natural gas using MALDI-TOF MS coupled with the SARAMIS microorganism database. The bacteria were isolated using the membrane filter technique and cultured in different selective media. Identifications were confirmed through 16S rRNA sequencing. Antibiotic susceptibility was also determined. A total of 25 bacteria were identified using MALDI-TOF MS. Of these, over 90% matched the RNA sequencing results. Bacillus spp. were the most prevalent organisms identified. Five species have been previously identified as human pathogens: Aeromonas hydrophila, Bacillus anthracis, Bacillus cereus, Pseudomonas aeruginosa, and Stenotrophomonas maltophilia. For antibiotic susceptibility testing, these 5 were resistant to most of the tested antibiotics.

Poster Number: 49


Neuroprotective Effect of Fig Fruit on Hippocampal Cell Line Exposed to Ethanol

Presenter: Nadine Shihabeddin, Chemistry and Biochemistry Undergraduate Student

Mentor: Dr. Subhrangsu Mandal

Abstract:

Fig fruit (Ficus carica L.) is a common part of the Mediterranean diet, and it is known to act as an antioxidant after consumption. To understand the potential of the fig fruit's ability to relieve oxidative stress and to assess its neuroprotective effect, hippocampal cell line (HT-22) were exposed to ethanol and to fig extracts simultaneously. The toxicity of the hippocampal cells was reduced significantly with the addition of the fig extract, and significantly higher cell viability was detected as compared to the ethanol treated control cells with no fig extract. These data suggest that fig can act as a neuroprotective agent with potential against oxidative- stress cell induced death, potentially leading to aid in neurological disorders that undergo oxidative stress.

Poster Number: 50


Assessing Environmental Microbiomes in Contaminated Groundwater Near Unconventional Oil and Gas Drilling using MALDI-TOF MS

Presenter: Michelle Reyes, Chemistry and Biochemistry Undergraduate Student

Mentor: Kevin Schug

Group Members: Misty S. Martin; Ines Santos; Doug D. Carlton, Jr.; Paula Stigler-Granados; Melissa Valerio; Christina Whitworth; Zacariah Hildenbrand; Kevin A. Schug

Abstract:

Groundwater hosts an overabundance of diverse microorganisms such as bacteria and fungi. Bacteria can thrive on hydrocarbons as they use it as a source of energy. Therefore, the presence of certain bacteria may be an indication of environmental contamination. Matrix-assisted laser desorption time-of-flight mass spectrometry (MALDI-TOF MS) is a more efficient method of identifying microbes as opposed to other conventional identification methods, which have proven to be more time consuming and costly. A unique mass spectral fingerprint is generated for each microorganism, which allows for an accurate identification when matched with a microorganism database. MALDI-TOF MS was used to identify microorganisms and assess the changes in microbiome diversity present in contaminated groundwater sources near unconventional oil and gas drilling sites over a period of time. Groundwater samples were obtained (n=19) from Frio County, Texas. The degree of impairment was assessed using gas chromatography mass spectrometry. Bacteria was isolated from samples using the membrane filter technique, then pure colonies were identified using MALDI-TOF MS. Several bacterial pathogens were identified, such as B. anthracis, A. hydrophila, S. maltophilia, P. aeruginosa, and C. amalonaticus, some of which are antibiotic resistant. However, two other bacteria which have been identified, P. putida and P. stutzeri, have been used in bioremediation due to their ability to break down toluene and carbon tetrachloride, respectively.

Poster Number: 51


Assessing the Microbiology of Malting and Brewing by MALDI-TOF MS

Presenter: Denise Reyes, Chemistry and Biochemistry Undergraduate Student

Mentor: Dr. Kevin A. Schug

Group Members: Michelle Reyes, Ines Santos

Abstract:

The process of malting and brewing is commanded by the effects of microbial activity, starting with the barley grain. Barley grain carries a microbial population of bacteria, yeasts, and filamentous fungi. Microorganisms' microbial activity drives the chemical reactions which are responsible for the fermentation of carbohydrates to synthesize alcohol. As a result of the interaction, microorganisms determine the technological, nutritional, and organoleptic properties of malt and beer as well as their microbial safety. These metabolic interactions will yield detrimental or beneficial effects, depending on the group and quantity of bacteria present. Of particular concern is the occurrence of mycotoxins that may affect the safety of malt and beer. To address these concerns, it is important to study the microflora during beer production to guarantee quality and safety. Matrix assisted laser desorption-ionization time of flight mass spectrometry (MALDI TOF-MS) can be an alternative to conventional methods for monitoring the malting and brewing processes since it provides a simpler and faster identification of bacteria. The mass spectrometer produces a spectral fingerprint that is unique to the microorganism being analyzed. The organism is then identified by comparing its spectral profile with a reference database. In this work, the microbial population of barley grains and hops was studied using MALDI-TOF MS. Bacteria were isolated using traditional plating methods and identified by comparing their protein profiles with the SARAMIS microorganism database. The bacteria identified with an 80 percent match or greater were Bacillus cerus, Bacillus atrophaeus/subtilis, Pantoea agglomerans, and Citrobacter sp. In the future, the microflora of malting and brewing will also be assessed using MALDI TOF-MS.

Poster Number: 52


Screening of Iotrochota Birotulata extracts with chloroform and Methanol/Toluene for antibacterial activity

Presenter: Zaynab Omisade, Chemistry and Biochemistry Undergraduate Student

Mentor: Dr. Laura Mydlarz

Group Members: Oshione Jimoh, Kim Nolasco, Julia Nguyen

Abstract:

Antibiotic-resistant bacteria are becoming increasingly problematic due to the limited amount of resources for treatments. Research in the pharmaceutical industry with marine organisms as a source of antimicrobial compounds has declined and is more focused on synthetic drugs. Therefore, to find a solution to the problem of antibiotic resistance, we look to marine natural products for its unexplored diversity as a promising source for drug discovery. In this study, we explored the drug potential of the sponge, Iotrochota Birotulata chosen for its abundance in the ocean, chemical defense mechanisms like dark-purple secretion which can be toxic, and its ability to escape the overgrowth of other organisms. The research involved extraction of compounds from the organism with MeOH/Toluene (3:1) and chloroform, And isolation of compounds of interest through solid-phase extraction (SPE). The antimicrobial activity of both crude extract and fractions from SPE was tested against both Gram positive and gram negative bacteria. Gas chromatography/mass spectrometry (GC/MS) and optical density were performed to characterize and assess the antibacterial potential of the compounds extracted from I. Birotulata. Results from bioassay from both optical density and disc diffusion provides evidence of anti-bacteria activity in I. Birotulata. The use of two different solvents for extraction also provides knowledge on what solvent is best for extraction and I. Birotulata seems to favor the more polar solvent MeOH/Toluene (3:1).

Poster Number: 53


DFT Study of Lithium Diffusion in Graphite and Silicon Oxycarbide

Presenter: Shariq Haseen, Chemistry and Biochemistry Undergraduate Student

Mentor: Peter Kroll

Abstract:

We investigate lithium diffusion in graphite and silicon oxycarbide materials by means of ab initio calculations in density functional theory. Graphite is used in the anodes of conventional lithium-ion batteries, and ongoing research is being done with silicon oxycarbide materials to determine their potential as alternative anode materials to graphite. Computational work is done in VASP using the universal low gradient method to correct for van der Waals attractions. The energy for optimized models of graphite, graphene, lithium graphite, and lithium silicon oxycarbide are found via ab initio calculations. Utilizing the approach of an elastic band method, the minimum energy path between two sites of lithium storage in lithium graphite and lithium silicon oxycarbide is determined. With the minimum energy path known, the diffusion coefficient of lithium can then be found in each anode material helping elucidate lithium diffusion in lithium-ion batteries in hopes of improving lithium storage in batteries.

Poster Number: 54


The Discovery And Analysis Of Antibiotic Compounds Within Metabolites Extracted With varying pH from Agelas conifera

Presenter: Edgar Rodriguez, Chemistry and Biochemistry Undergraduate Student

Mentor: Dr. Laura D Mydlarz

Group Members: Susana Pimentel, Stanley George, Nicholas Smith

Abstract:

Sponges (Porifera) have played an important role in drug discovery, as they prolifically produce useful secondary metabolites that have been proven to effectively inhibit the parthenogenesis of debilitating infectious diseases. The compounds in the Caribbean sponge Agelas conifera have been especially useful to drug research and synthesis. In this study, we extracted crude samples of A. conifera using pure Methanol, Methanol that was buffered to have a pH of 4, and Methanol that was buffered to have a pH of 10 in order to observe if pH level affected the kinds of compounds extracted. Optical density and bacterial assays against E. coli and Bacillus subtilis were performed on the crude extracts in order to document bacterial inhibition as well as characterization of the crudes using GC/MS. Results from optical density showed that there was activity against Bacillus subtilis from the crude sample extracted with pH 4 methanol and activity against Escherichia coli from the crude samples extracted with pH 10 methanol and pure methanol. GC/MS proved that there was a compound similar in structure to paromomycin from the pH 10 crude extract and cholesterols, anilines and acids in all of the samples tested.

Poster Number: 55


Characterization and Formation of Perfluoro alcohol/acid Induced Coacervates

Presenter: Armin Oloumi, Chemistry and Biochemistry Undergraduate Student

Mentor: Dr. Morteza Khaledi

Group Members: Stephan Clayton, Ariel O’Brien, Amir Koolivand

Abstract:

Surfactant based coacervates are induced by perfluoro alcohols and acids in various conditions. The formation of a coacervate system depends on the balance between intermolecular interactions such as hydrogen bonding, electrostatic, hydrophobic, and other weak interactions. The combination of an anionic and/or catanionic surfactant (sodium cholate, sodium deoxycholate, cetrimonium bromide, and tetrabutylammonium bromide) with a coacervate inducer such as perfluoro alcohol/acid at different conditions (pH and salt concentrations) was evaluated and the phase diagrams were created. The micro-scale optical digital microscopy images were obtained for coacervate phases. The pH of coacervate phases in different systems was compared by adding a pH sensitive dye, Thymol blue. The cationic surfactants formed two-phase systems only in basic pH, however, anionic surfactants need acidic pH to form a coacervate. The mixture of both cationic and anionic surfactants formed coacervate phases without a need to alter the pH. The micelle-like structure of the coacervate phases was identified in optical microscopic images . Here we provided the forming conditions of different surfactant based coacervate systems with different types of coacervate inducers. These two phase systems can be used to extract or enrich hydrophobic molecules such as proteins, therefore investigating their types and forming conditions is very useful for choosing the right system in further extraction and enrichment studies.

Poster Number: 56


Surfactant Based Coacervation in Protein Extraction

Presenter: Halie Rion, Chemistry and Biochemistry Undergraduate Student

Mentor: Morteza Khaledi

Group Members: Stephan Clayton, Amir Koolivand

Abstract:

Surfactant coacervation refers to a two-phase system in which both a dilute aqueous phase and a surfactant-rich phase exist in equilibrium with one another. Surfactant based coacervate formation can be induced by perfluoro alcohols and acids under various conditions. The combination of a surfactant (Sodium Cholate, Sodium Deoxycholate, Tetra-n-butylammonium bromide, and Cetrimonium bromide) and a perfluoro alcohol/acid under differing conditions (such as pH and NaCl concentration) were evaluated for the extraction of model proteins. In each system, a washing procedure such as, acetone precipitation, methanol/chloroform precipitation, or ethyl acetate back extraction, was performed to remove surfactants from the separated coacervate phases. The optimal systems were utilized to extract and enrich proteins from the lysate of baker yeast cells, a well-known organism in the study of proteomics. The yeast cells were grown for 12 generations and lysed with a mechanical lysing method. The protein concentration was measured by a Bradford protein assay. The coacervate systems in cell lysate were then prepared by adding enough surfactant (25-50 mM) and 10-20 % (v/v) coacervators, such as hexafluoro-2-propanol. The recovered concentrations of proteins in both the aqueous and the coacervate phases were measured for comparison. These results showed that more than 70% of the proteins were enriched in the coacervate phase. Due to the hydrophobic nature of the coacervate phase, the coacervate phase extracted more membrane proteins compared to the aqueous phase. These results indicate potential for the use of surfactant based coacervation in protein extraction and therefore, may be applicable in membrane proteomics where the lower abundance of membrane proteins creates challenges which limit both detection and identification.

Poster Number: 57


Application of Dynamic Light Scattering (DLS) to the Measurement of Diffusion of Biopolymers in Buffered Solutions

Presenter: Aaron West, Chemistry and Biochemistry Undergraduate Student

Mentor: Dr. Peter Kroll

Group Members: Dr. John Lang

Abstract:

Light scattering is a physical phenomenon that can be used to characterize changes in optical properties of the media through which light is passing. Dynamic light scattering (DLS) is a derivative technique that takes advantage of the time-dependent fluctuations of this scattered light generated by the motion of scattering sources, which for chemical applications range from single molecules to microscopic particles. These sources undergo diffusion by Brownian motion that can be analyzed by DLS to provide information about source geometry and interactions. In this work, DLS is being used to study the effects of particle charge and average interparticle distance on the diffusion coefficient of bovine serum albumin (BSA), a highly studied animal-derived blood protein. The investigation is examining the effects of protein volume fraction and solution ionic strength on protein diffusion in buffered solutions at a pH of 5.4. The robustness of this protein allows it to serve as a prototype unencumbered by issues of stability. Investigations show several effects of ionic strength on the dependence of diffusion upon concentration. The effective particle size becomes smaller at higher ionic strength, since the intraparticle charge-charge repulsion is reduced. With reduced interparticle repulsion, the mean free path between effective macromolecular collisions is longer but the diffusion distances traversed per unit time are shorter. Observations indicate the latter effect dominates, with rates of diffusion decreasing at higher ionic strength. At even higher ionic strength and increased charge screening, aggregation can be observed, a consequence of attractive van der Waals interactions. Future work will seek to study protein interactions at temperatures below ambient temperature, with an aim to apply this technique to the study of biopolymers more sensitive to denaturation.

Poster Number: 58


Potential Antibacterial Properties of the Marine Sponge Aplysina fulva through Metabolite Extraction

Presenter: Stephanie Dinh, Chemistry and Biochemistry Undergraduate Student

Mentor: Dr. Kevin Schug

Group Members: Marwa Elsaad, Stefany Gaubatz, Julyanna Tao

Abstract:

According to the Centers for Disease Control (CDC), at least two million people in the United States every year are infected by antibiotic-resistant bacteria, with over 23,000 of these individuals dying. To address this growing need for new antibiotics, research was conducted using marine sponges, which have endogenous compounds shown to exhibit antibacterial properties. Due to its abundance of metabolites, the sponge Aplysina fulva was chosen. Compounds were extracted from Aplysina fulva with ethanol. These compounds were later fractionated based on polarity and then tested for antibacterial activity using disk diffusion. Crude extracted compounds displayed antibacterial activity against all four tested bacteria, with B. subtilis and S. marcescens undergoing the largest growth of inhibition at 1.63 cm and 1.35 cm, respectively. Gas chromatography-mass spectrometry (GC-MS) was conducted to analyze the components of our sample, some of which were cross-referenced to have antibacterial properties. Additionally, optical density was conducted to quantify how effective endogenous compounds were in inhibiting bacterial growth. The extract competed on par to known antibiotics in optical density readings. In conclusion, compounds found in A. fulva are capable of inhibiting bacterial growth and thus have potential to lead to the formation of new antibiotics.

Poster Number: 59


The Effects of Culling and Quarantine on Reducing Antibiotic Resistance in a Cohort of Beef Cattle

Presenter: Mary Gockenbach, Mathematics Undergraduate Student

Mentor: Christopher Kribs

Group Members: McKenna Cortez (University of Nevada - Reno), Ying Huang (Shanghai University), Noah Padgett (University of Wisconsin - Whitewater)

Abstract:

Antibiotic resistance is a global health concern that involves animals as well as humans. In zoonotic diseases, not generally fatal to humans, antibiotic resistance provides a reservoir from which pathogenic bacteria can gain resistance. Reducing antibiotic resistance in bovine infections is a key part of any plan to slow resistance in human diseases. A two-stage mathematical model is constructed in order to find the most ideal combination of isolation, treatment, and culling that reduces the number of beef cattle with antibiotic resistance at the time of maturity. New legislation, starting in 2017, will restrict the use of antibiotics in cattle feed to veterinary prescription. To compare the impact of this legislation with current practices, an additional set of parameter values is used to simulate the dynamics of antibiotic resistance among beef cattle populations. Culling rates are shown to have a negligible effect, but quarantine rates of 0.5-1 per week lead to a decreased ABR rate.

We find that under the new legislation the proportion of cattle with ABR at slaughter decreases by a statistically significant amount. In addition, the number of cattle colonized with antibiotic susceptible bacteria increases.

However, the proportion of sellable cattle at the time of slaughter remains roughly the same.

Poster Number: 60


A Mathematical Model of Skeletal Muscle Regeneration

Presenter: Elizabeth Stephenson, Mathematics Undergraduate Student

Mentor: Hristo Kojouharov

Abstract:

We introduce a system of seven ordinary differential equations modeling the response of healthy mammalian skeletal muscle tissue to sudden and severe damage. The system is analyzed, yielding one stable, biologically meaningful equilibrium. A set of numerical simulations is performed to illustrate the performance of the proposed equations. We conduct a sensitivity analysis to rank the parameters' influence on the system. This model can help doctors and scientists forecast the outcomes of medicinal treatments prior to implementation.

Poster Number: 61


Effects of Eccentricity and Ellipticity on the Magnetic Field for Horn A of the Deep Underground Neutrino Experiment

Presenter: Eric Amador, Physics Undergraduate Student

Mentor: Dr. Jaehoon Yu

Abstract:

The focusing horns for the Deep Underground Neutrino Experiment will be given an ellipticity and eccentricity in order to study the effects of ellipticity and eccentricity on pion distribution and neutrino flux for DUNE using Monte Carlo simulations. The magnetic field will be deformed and studied extensively in order to measure the focusing power of the horn on the low momentum pions created by impacting protons at relativistic speeds against a target inside the horn.

Poster Number: 62


Determination of systematic uncertainty due to PDF variations during search for invisibly decaying Higgs Boson produced through Vector Boson Fusion in proton-proton using the ATLAS detector at the LHC

Presenter: Darshan Chalise, Physics Undergraduate Student

Mentor: Dr. Andrew White

Group Members: University of Pennsylvania: Bill Balunas(GS), Elliot Lipeles (F)

Saclay (France): Marta Perego(GS), Claude Guyot (F), Marco Cirelli (F)

University of Chicago: Jamie Saxon(PD), Rui Zou (GS), Young-Kee Kim (F)

DESY (Germany): Alex Madsen (PD), Krisztian Pet

Abstract:

The ATLAS collaboration is currently conducting an analysis on search for invisibly decaying Higgs Bosons produced through Vector Boson Fusion (VBF) during proton-proton collisions at the energy of 13 TeV at the Large Hadron Collider(LHC). The analysis requires Monte-Carlo data samples for comparisons when estimating the background. Parton distribution function (PDF), which defines the probability density of a particle with certain longitudinal momentum at a certain resolution, determines the outcome of the Monte-Carlo event generation. There is no theoretical model for PDFs and different PDFs have been determined by different experiments. Therefore, choosing a specific PDF set causes a systematic uncertainty in the analysis. This research at UTA provides an estimate of the systematic uncertainty caused by using a specific pdf set. NNPDF3.0 was selected as the PDF set for the analysis as per the recommendation by the collaborators. 20,000 NLO and 50,0000 NNLO events were generated using POWHEG Event Generator and Truth Reconstruction was run on them. Standard cutflow was applied and number of events passing each cuts were calculated. Total variation of 1.7% was calculated for NLO events with variations of 2.4% and 0.93% on events with jet mass range 1-1.5 TeV and 1.5-2 TeV respectively. For NNLO events, total variation of 0.9% was obtained with variations of 1.1% and 0.93% respectively on the jet mass ranges listed above. These variations are significantly less than the 2.8% given by CT10 PDF set used in previous ATLAS analysis. This suggests NNPDF3.0 is preferable than CT10 to reduce systematic uncertainty.

Poster Number: 63


Earth's Cousin, Kepler 452b

Presenter: Niyousha Davachi, Physics Undergraduate Student

Mentor: Dr. Z. Musielak

Group Members: Marialis Rosario Franco, Sergio Garza

Abstract:

Kepler 452b, also nicknamed Earth's cousin, was discovered orbiting the habitable zone (HZ) of a G2 Star (Jenkins et al. 2015). This exoplanet is considered a super Earth, with a mass of 5 Â± 2 MâŠ• and a radius of 1.11 RâŠ•; and is arguably the first rocky, habitable exoplanet to orbit a sun-like star. With a period of 385 days, conditions are prompt to be similar to those of Earth, and while Kepler-452b orbits the HZ of its parent star, its habitability could also be affected by the presence of an exomoon. Motivated by the need to understand conditions of habitability and orbital stability of Kepler-45b, we have performed a series of N-body integrations to examine the possibility of the exoplanet hosting an exomoon(s). Our results give a range of physical parameters leading to stable orbits for exomoons around this habitable super Earth.

Poster Number: 64


The Relationship between Temperament, Externalizing Behaviors and Family Factors in Young Children

Presenter: Sydney Cox, Psychology Undergraduate Student

Mentor: Dr. Jeffrey R. Gagne

Abstract:

The current study was designed to examine young child negative affect and difficult temperament behaviors and maternal negative personality traits and mental health symptoms as predictors for these behavior problems. Mothers completed surveys that assessed child temperament and behavior problems, and the mother's personality traits and mental health symptoms. We hypothesized that children who display high levels of negative affect behaviors (poor impulse control and anger) are more likely to have higher levels of externalizing behavior problems such as aggression. We also predicted that negative caregiver personality traits and mental health symptoms will be associated with the child variables studied. Bivariate correlations and regression analyses were calculated on the data. Results showed that children that had negative affect behaviors such as anger and impulse control (IC) were more likely to have behavior problems like aggression or Oppositional Defiant Disorder (ODD). Maternal personality traits and mental health symptoms were also shown to have a negative influence on their child's behavior. Hierarchical regression analyses were calculated to account for child gender and demonstrated that maternal trait anxiety predicted child ODD behavior problems and maternal neuroticism predicted child aggressive behavior problems. The implications of associations between child negative affect, temperament, and behavior problems, and maternal personality traits and mental health symptoms are discussed.

Keywords: externalizing behaviors, delinquency, negative affect behaviors, maternal negative personality traits, maternal mental health

Poster Number: 65


The impact of attitudes toward on diversity on perceived team performance

Presenter: Robert Tait, Psychology Undergraduate Student

Mentor: Paul B. Paulus

Group Members: Belinda Williams, Nasheha Baset, Jubilee Dickson, Jared Kenworthy

Abstract:

Although some researchers suggests that both personal and functional diversity are beneficial to performance in workgroups (Watson, Kuman & Michaelson, 1993; Jackson, 1996), there is limited research on how an individual's attitude toward working in a diverse group may impact self-reported measures of group performance (Nakui, Paulus, & van der Zee, 2011). In order to examine this, we predicted that an individual's score on both affective and productive measures of the Attitude Toward Diverse Workgroups Scale (ADWS; Nakui, Paulus, & van der Zee, 2011), would predict positive perceptions of team performance. Participants were 421 undergraduate students (60% female) with a mean age of 21; racial breakdown included 29% Caucasian, 24% Hispanic, 22% Asian, 16% African-American, and 7% other. Participants were randomly assigned to work in groups of either 3 or 4. Groups worked asynchronously, using an online discussion board, to generate ideas independently and as a group. Groups then furthered idea generation in a synchronous, face to face, portion of the study. There was a significant, positive relationship between scores on the ADWS and self-reported perceptions of team performance. As scores on the ADWS increased, positive perceptions of team performance increased. As organizations seek to increase personal and functional diversity in workgroups, our findings suggest that understanding and influencing employee's attitudes toward diverse workgroups may result in more positive reactions to participating in these groups.

Poster Number: 66


The Relationship between Personality, Performance, and Group Cohesion

Presenter: Nasheha Baset, Psychology Undergraduate Student

Mentor: Paul B. Paulus

Group Members: Tait, Robert R., Williams, Belinda C., Dickson, Jubilee J., Paulus, Paul B., Kenworthy, Jared B.

Abstract:

Previous researchers have examined the relationship between personality and performance (Fullarton, Fuller-Tyszkiewicz, & von Treuer, 2013) at the individual level. Other researchers have included additional variables for examination including cohesion. A study by van Vianen and De Dreu (2010) found a strong positive relationship between personality and outcome measures of cohesion (task and social) and performance. The investigation of group composition variables continue to be relevant as workgroups and teams are constantly changing. Personality and the relationship it has with cohesion and performance is dynamic in nature and requires continued investigation. In order to expand on the current literature, we predicted that cohesion would mediate the relationship between personality and team performance. Participants were 421 undergraduate students of which 253 were female, with a mean age of 21 and a racial breakdown of 29% Caucasian, 24% Hispanic, 22% Asian, 16% African-American, and 7% reported "other"�. We found that group cohesion significantly mediated the relationship between personality and perceived performance outcomes. This finding adds to the field by helping us understand how individual differences and the underlying processes of group work lead to the perceptions of group productivity.

Poster Number: 67


The Influence of Gender Nonconformity on Levels of Outness

Presenter: Lou Lindley, Psychology Undergraduate Student

Mentor: Dr. Nagoshi

Group Members: Ben Blankenship, psychology doctoral student at University of Michigan; Patrick R. Grzanka, Professor at The University of Tennessee at Knoxville; Gabrielle Filip-Crawford, Assistant Professor at St. Catherine University

Abstract:

Gender nonconforming individuals are assumed to be homosexual due to their gender role inverting behaviors. It was hypothesized that due to these assumptions, lesbians and gay men who are members of queer identity groups that invert gender roles (i.e. "twinks" or "butch lesbians") would have higher levels of outness than gender conforming groups (i.e. "bears" and "femme lesbians"). These queer identities were assessed in terms of gender role associations, using the PAQ masculinity and femininity subscales, and outness measured by the Outness Inventory (Mohr & Fassinger, 2000). Results of the study found that the men (N=233) had a positive linear relation of outness to feminine gender role identity, while women (N=216) had a significant quadratic relationship, such that the highest and lowest scorers on feminine gender role identity identified as the most out. While effeminate gay men do show higher levels of outness than gender conforming gay males, this was not true of lesbians. This could be due to femme lesbians not having well-structured organization like that of "bears", therefore requiring higher levels of outness in order to find a community of others. These results show that outness is more than just a verbal announcement of homosexuality, it can have a behavioral aspect as well.

Poster Number: 68


Effects of Therapy Dogs on Mood States of College Students

Presenter: Frank Cooley, Psychology Undergraduate Student

Mentor: Dr. Scott L. Coleman

Group Members: Anna Cooley, Samantha Vorsino, Grayson Watson, Toan Nguyen,Parisa Khaghani, and and Angela Liegey-Dougall

Abstract:

Purpose: Human interaction with dogs and other domesticated animals affords multiple physiological and psychological benefits. Numerous studies show a reduction in anxiety, blood pressure, and heart rate among other well-being indices. These effects have been identified in critical human populations with cognitive, development, social, and cardiovascular health disorders. More recently, research has investigated the impact of human/animal interactions in pedagogical domains. The present study investigated the effect of human-animal interactions on the short-term mood states of college students. Method: Two hundred-forty college students served as participants in this study. Participants were recruited from a large pool of students that attended regularly scheduled therapy dog visitation at the central library on the UTA campus. This study utilized a questionnaire format to assess the mood states of participants immediately before and after interaction with therapy dogs. Mood states were measured using the Profile of Mood States short form (POMS-SF) Shacham (1983). In addition to mood state assessment, participants indicated areas of physical contact (i.e., petted) on the therapy dog using a check list. The duration of the interaction with the therapy dog was also obtained. Thus, the questionnaire provided measurement of length of time and topographical characteristics of the participants' human-animal interaction. Results: As expected, total negative mood disturbance decreased from before (M = 47.60, SE = 1.73) to after (M = 21.61, SE = 1.08) engaging in physical contact with a therapy dog, F(1, 224) = 368.16, p < .001, Î·p2 = .62. Participants with higher negative mood prior to the session had larger decreases during the session, b = -0.65, SE = 0.03, t(221) = -20.21, p < .001. However, this effect was enhanced by both greater time spent with the therapy dogs, b = -0.006, SE = 0.003, t(217) = -2.28, p = .02, as well as the more total contact areas, b = -0.025, SE = 0.007, t(217) = -3.64, p < .001. However, time spent and areas touched were only marginally associated, r(223) = .13, p = .05. Conclusions: College students face challenging day-to-day situations that provoke negative mood states, stress, and anxiety. Our study demonstrated the efficacy of instituting an on-campus therapy dog program to ameliorate negative mood in college students. Given the current findings, we anticipate the existence of a wide range of therapeutic effects.

Poster Number: 69


Exploring Dating Practices among Burmese Refugees: A Qualitative Study

Presenter: Kristen Ravi, Social Work Graduate Student

Mentor: Dr. Beverly Black

Group Members: Dr. Diane Mitschke, Katelyn Pearson

Abstract:

Background: Although we know that teen dating violence is an important health concern among American youth and internationally, we know little about dating violence among resettled refugee adolescents in the US. Over 160,000 individual refugees from Burma, have resettled to the United States since 2006. As a first step in studying teen dating violence among the Karen, the largest ethnic group in Burma, it is imperative to first study dating relationships among Karen youth. Method: We conducted a focus group with Karen refugee youth (n=6) with ages ranging from 15-22. A semi structured focus group guide was used to interview youth about their views of gender roles, relationship norms, healthy and unhealthy relationships in American and Karen cultures. Results: Three themes emerged from the youths' discussion of Karen dating practices and their views of American dating practices. The themes focused on issues related to: (1) gender roles, (2) dating practices, and (3) healthy vs. unhealthy relationships. Participants discussed the influence of acculturation within each theme. Implications: This study provides a starting point in learning about how issues related to teen dating violence (TDV) may be addressed within the Karen community. This information may be helpful in developing culturally competent dating violence prevention programming.

Poster Number: 70


A Bounded Case Study of the World’s Largest Biometric Identity System Improving Health and Welfare Services to the Poor

Presenter: Skylar M.G. Joyner, Social Work Graduate Student

Mentor: Dr. Randall Basham

Group Members: Dr. John Bricout

Abstract:

The imperative of sustainable inclusive development includes a total governance approach committed to the identification and sustainable solutions of the twenty-first century world, where technology has reached the point of affordability and scale to help address and solve key core root causes of social, economic, and political disadvantages of social justice. Aadhaar is one specific identified program that is indeed grounded in social justice and it is fundamental to achieving a socially, economically and environmentally sustainable future for everyone.

The promise of inclusive social protection central to India's Aadhaar social welfare program, which is a national initiative using biometric information to allocate unique identification numbers to Indian residents. Aadhaar has reached over one billion people and promises to expand access to basic identification, improve enrollment in social protection and financial inclusion programs, curb leakages and systemic fraud, reduce corruption and address other gaps in India's social protection architecture that is replicable to other countries once scholarly discourse and dissemination such as this presentation occurs on a grand scale.

In summary, this presentation assesses and analyzes Aadhaar's aims to achieve inclusive social protection through personal, civic, functional and entrepreneurial inclusion in a sustainable manner leveraging biometrics and technology in a qualitative bounded case study format. Aadhar serves as a testament and demonstrates a concrete exemplar of how the underserved and unserved sections of rural society can be strengthened via technology and governance working together in an effort to reduce poverty. This program originally has a specific focus on the sustainable improvements of the conditions of rural people; especially women and children by strengthening their economic, health and education status, enabling to build accessibility and control over issues affecting their lives.

Poster Number: 72


Poverty Alleviation Solutions

Presenter: Maria Cole, Social Work Graduate Student

Mentor: Marta Mercado, Ph.D.

Abstract:

Background

Current poverty alleviation legislation provides some economic relief to select families, but fails to address the psychosocial needs of the marginalized population. The primary non-medical poverty alleviation policies are Temporary Assistance for Needy Families (TANF) and the Supplemental Nutrition Assistance Program (SNAP). These programs have remain largely unchanged since their adoption in 1996 despite persistent and worsening poverty nationwide.

Methods

I conducted a comprehensive literature review which revealed that poverty is a leading factor in mortality, education, crime, and health-related quality-of-life outcomes. Several studies illuminated community engagement activities, agendas, and initiatives that have helped to mitigate poverty. These bodies of evidence presented evidence detailing factors that contribute to poverty conditions, and offered several evidence-based, effective programs to combat poverty.

I constructed a cost-benefits ratio to examine TANF's costs and outcomes. Next, I utilized public policy analysis' normative methods to review policy effectiveness. Finally, I compared the costs-benefits ratios of several validated poverty alleviation programs to the costs of the TANF program.

Results

The TANF and SNAP programs account for about $362 billion annually. There was no conclusive evidence, however, that TANF policies decrease poverty. In contrast, implementation costs of the reviewed programs cost less than current TANF programs and yielded more positive results.

Conclusions

The indicators that predict poverty also render it nearly inescapable. Individuals who experience poverty may be unable to avoid their plight and continue to reproduce under like conditions, thereby, enabling inescapable poverty to persist. Evidence-based supplemental programs are needed to help alleviate poverty.

Poster Number: 73


Understanding Mental Health Literacy in a Primary Care Setting: Examining the Relationship between Depression Stigma, Depression Knowledge and Education Level of Hispanic Patients

Presenter: Veronica Lopez, Social Work Graduate Student

Mentor: Katherine Sanchez

Abstract:

Depression is a leading cause of disability in the U.S. Incorporating mental health literacy tools in a healthcare setting may improve the tools used for early detection of mental illness and can help engage a patient into treatment. The study examines the relationship between stigma and depression knowledge and examines if education level can predict stigma and depression knowledge. Participants were from a Fort Worth community clinic, screened positive for depression. The baseline measures collected and examined were the depression knowledge(DKM), social distance(SD), stigma concerning mental health care(SCMHC) and Latino scale for antidepressant stigma(LSAS) Measures, all collected prior to treatment.

Of the 350 participants, nearly all participants were Spanish speaking (94.9 %) with a mean age of 38.81 (SD=10.60). Almost two-thirds of the sample had less than a high school education (63.7%) and 14.0% had at least some college education. DKM scores were significantly correlated with SCMHC scores (r=-.118, p=.029) and with social distance(SD) scores (r=.157, p=.003), albeit weakly. DKM scores (F[2, 336]=16.181, p<.001), social distance(SD) scores (F[2, 339]=3.665, p=.027), and LSAS scores (F[2, 336]=3.152, p=.044) significantly varied amount education groups. In each case, participants with some or more college education reported significantly greater depression knowledge and less stigma surrounding mental health issues than participants with lower education levels. In conclusion, the study suggests that obtaining a well-rounded picture of the clientâ€™s education level, stigma through the measures, and depression knowledge may allow for a more thoughtful application of an intervention that can help engage a Hispanic client into treatment.

Poster Number: 74


Self-determined goals by offenders of intimate partner violence: Does it work in changing the men who abuse?

Presenter: Anh Phuong Nguyen, Social Work Graduate Student

Mentor: Peter Lehmann

Abstract:

Group work with abuse of intimate partner violence (IPV) has mainly focused on psycho-educational programs that usually overlook the roles of goal setting by the offenders. Several alternative approaches have been proposed over the years. Of these, Solution-focused brief therapy (SFBT) represents the sole practice modality within the batterer intervention field that has drawn on the notion and importance of strengths-based goal settings with this population.

The primary purpose of this preliminary study was to examine the utility of self-determined goals as a venue for change through a solution-focused treatment program of IPV offenders. This preliminary study was a pretest posttest design to investigate the role of self-determined goals among IPV offenders. The sample included case files of 150 male offenders convicted of IPV who participated in an ongoing North Texas criminal court diversion program. The 150 men were chosen from ongoing cases files of men who had completed psychological evaluation in response to their criminal dispositions.

Findings of the study revealed an overarching theme, which was seen as the offenders' "accountability for change" process. This theme was illustrated through narrative and content analysis of four specific self-determined goals: Instrumental (communication) goals, (ii) Emotion regulation goals, (iii) Engaging in Relationship/ Commitment goals, and (iv) Improving skills in resolving family conflict goals. Findings of this preliminary study provided empirical evidence regarding the role of self-determined goals in reducing violence in male IPV offenders.

Conclusion: Social workers working with this men who may be abusive towards their partners must recognize and utilize the potential power strength that each of their offending clients have. One way to do this may be through goal setting with each man. The finding of this study fosters the use of strength-based approach for a population that are usually not strongly supported for this theory. It also supports NASW Code of Ethics, specifically in the value of Social work ethical principle, whereby social workers respect "the inherent Dignity and Worth of the Personâ", and respect and promote "the right of clients to self-determination and assist clients in their efforts to identify a

Poster Number: 75


Identification of Leaders and Followers in US-Listed Indian ADRs and Domestic Listings of Underlying Stocks

Presenter: Shivam Arora, Finance and Real Estate Undergraduate Student

Mentor: David Rakowski

Abstract:

Information transfer between developed stock markets and major emerging markets around the world has expanded recently, with emerging market companies increasingly issuing securities in developed markets in order to finance their new-found needs for capital. This paper analyzes the lead-lag relationships between American Depository Receipts of Indian companies traded on major US stock exchanges and their respective underlying stocks traded in India. By using the univariate ordinary lease squares regression statistical method, the study examines the strength of predictive signals between Indian and US markets. The study finds evidence of bi-directional causality. The strength of this predictive signal is stronger when US stock index returns are used to predict Indian index returns, than when Indian index returns are used to forecast US index returns. However, individual underlying Indian stock returns are stronger predictors of corresponding individual US ADR returns than vice-versa.

Poster Number: 76


Brightness-Hierarchy Congruence Effect: Darker Comes First

Presenter: Jin Chung, Marketing Graduate Student

Mentor: Saini Ritesh

Abstract:

I propose a brightness-hierarchy congruence effect where consumers relate color lightness (darker versus. lighter) with inter-item hierarchy (higher versus. lower). In other words, people associate a higher hierarchy item (e.g., a shampoo) with a darker color (e.g., dark navy packaging color), and associate a lower hierarchy item (e.g., a conditioner) with a lighter color (e.g., sky blue packaging color). Hence, in the domain of complementary products, those bundles where the primary product is darker and the secondary product is lighter in packaging are more preferred than any other bundle configuration.

Two studies (study 1 =97 participants, study 2 = 81 participants) confirmed that people prefer the congruent bundles. Specifically, the dark-colored detergent (shampoo in study 2) paired with light-colored softener (conditioner in study 2) induced more positive product evaluation than any of the other three paired bundles (p=.012 in study 1, p=.005 in study 2).

In study 3, 250 participants of AMTurk were asked to categorize 16 different sets containing of a higher hierarchy and a lower hierarchy item (e.g., a main & a side dish). They were asked to put each of the items into a darker or a lighter colored basket as they saw fit. Results revealed that 76% of the categorizations were congruent, where the higher hierarchy item was tagged with the darker color basket (Binomial Test, p>0.0001).

In study 4, 250 participants of AMTurk answered to 8 scenario-based questions where they have to choose the more suitable products (darker vs. lighter) for two different people or item (higher vs lower hierarchy). 82% of the choices were congruent, where a darker product was chosen for the higher hierarchy person or item (Binomial Test, p>0.0001). We also examined an individual difference which moderates the effect demonstrated in previous studies. According to Neuberg and Newsom (1993), people possess a different degree of tolerance for information ambiguity, a trait referred to as the “personal need for structure” (PNS). Results revealed that PNS is highly correlated with participants’ rate of congruent choices (r=+0.176, p=0.005). People high in PNS chose darker objects far more often for a higher hierarchy item.

Four studies convergingly demonstrate that individuals tend to link a higher (lower) hierarchy item to a darker (lighter) color. We also demonstrated that a consumer’s “need for structure” moderates this preference.

Poster Number: 77


Dependency of used car price on odometer reading and exterior color

Presenter: Samia Jannat, Management Graduate Student

Mentor: Dr. Pradip Som

Abstract:

Used car business makes profit by selling used and preowned cars. This is a very lucrative business if someone knows his/her buyers and sellers very well. This current work shows the correlation between the value of used car and the odometer reading of Toyota, Honda and Ford cars in Texas. For Toyota, the price of sedans is heavily dependent on odometer reading. With the current data, 74.52% of the price variation of sedans is explained by the odometer reading whereas for SUV, van and truck, the numbers are 67.48%, 56.61% and 60.85%. This study also includes exterior color as a controlling variable of car's price. It was observed that for black Toyotas, the correlation between car price and odometer reading is very strong with correlation coefficient of 0.86 while for red Toyotas, it is only 0.03 suggesting that over time, the car price of red Toyotas decline slower than the black ones. For Honda, the scenario is a little different. Odometer reading is responsible for 97.84% of price variation of Honda vans whereas for sedan, SUV and coupes, the correlation is weak. Unlike Toyota, price of red Hondas decline faster than black cars over time. Again, for Ford, 69.26% of the price variation of coupes is explained by the odometer reading while for sedan, it is 67.81%. Red Fords have more consistent price over time than the black Fords. For Toyota and Ford, the overall correlation is strong between the price and odometer reading with correlation coefficient of 0.52 for Toyota and 0.69 for Ford. For Honda, the correlation coefficient of 0.22 suggests a weak dependency of price on odometer reading.

Poster Number: 78


Handwriting Apps in the Kindergarten Classroom Enhance Manual Dexterity but not Handwriting Skills

Presenter: Christi Butler, Curriculum and Instruction Graduate Student

Mentor: Priscila Cacola

Group Members: Dr. Jodi Tommerdahl

Abstract:

The draw of enticing students' gain of knowledge through the use of technology in the classroom is growing in popularity. Educators' concerns regarding authentic learning increases as more responsibility is given to the student and technology is being used. The purpose of the present study was to determine whether the use of handwriting apps was effective in improving Kindergartners' manual dexterity and handwriting skills. Two groups were tested, a control group (n=70) that practiced traditional worksheets, and an experimental group (n=58) that used a combination of traditional (worksheets) and iPad apps (with a stylus) for about 25% of the time. The groups were tested before and after the first semester of Kindergarten with the Manual Dexterity (MD) portion of the Movement Assessment Battery for Children and the Evaluation Tool of Children's Handwriting (ETCH). A 2 (Group) x 2 (Time) general linear model analysis was employed to determine if differences occurred. Results indicated a significant interaction for MD (p < .03), with a significant improvement in the experimental group and no significant differences for the ETCH. While the iPad is helpful for manual dexterity, an important ability underlying the skill of handwriting, it does not seem to translate into word, letter, and numerical legibility, which are important aspects of handwriting. Therefore, the use of the iPad, if only dedicated to handwriting, may have to be monitored and supplemented in order to be an effective authentic learning tool.

Poster Number: 79


Introducing Mathematical Concepts to Children in Early Infancy Through the Medium of Television: A Proposal for a Content Analysis

Presenter: Valerie Maxine Hernandez, Curriculum and Instruction Graduate Student

Mentor: Jiyoon Yoon, Ph.D.

Abstract:

With proper monitoring of age-appropriate educational television, young children increase their cognitive abilities, vocabulary skills, and readiness in math literacy. The study investigated ten selected television programs with the target audience ages 2 through 5-years-old to find out what kinds of and how math concepts are exposed to the young children. Two trained interraters reviewed and coded the TV programs by putting a tally mark on a rubric each time an attribute was mentioned in the television show. The final score per attribute for the TV show was added to a master rubric. The study resulted that more than half of the programs came up with more boys than girls on the shows and most of the programs covered only one math concept, counting, except three programs. Three of the programs introduced the math concepts only in verbal representation, three programs used both verbal and Arabic representations, and four programs provided verbal, Arabic, and magnitude representations. This study would be beneficial for parents and teachers to select the age-appropriate TV program especially for improving math literacy.

Poster Number: 80


Women of Color Leading Community Colleges

Presenter: Maria Delgado, Educational Leadership Graduate Student

Mentor: Dr. Taryn Allen Ozuna

Abstract:

Using De Anda's (1984) framework of Bicultural Socialization theory that indicates that individuals from minority groups have to learn to function in two environments, the environment of their own culture and that of the main society culture. This research study presents findings from a qualitative study that examined how women of color (African American, Asian American, American Indian, and Hispanic) navigated the community college system and were able to achieve success by obtaining higher-level administrative positions. Five women of color who hold higher ranking administrative positions at a community college district in Texas shared their experiences, achievements, adversities, and resiliency approaches. It also examined obstacles these women of color encountered, the individuals and resources that supported their success and the role that culture played in their professional success. The significance of this study expands the literature about women of color in higher-level administration and contributes to the change in the hiring practices that community colleges currently use. Fully understanding the extensiveness of women of color in higher-level administrative positions in community colleges in Texas is important because women of color serve as an asset and resource for students, thus the significance of this study also provides a paradigm to current community college leaders about practices for employee recruitment and retention that benefit women of color. Lastly, this study contributes to the literature about the influence that culture has in the career path of women of color in higher-level administrative positions. Recommendations for practice and future research are also discussed.

Poster Number: 81


Quadricep Inhibition in Regards to Strength of Affected Knee Compared to the Non-Affected Knee after Knee Surgery in Short and Long-Term as Measured by Torque

Presenter: Chase Newby, Kinesiology Undergraduate Student

Mentor: Dr. Cindy Trowbridge

Group Members: Alyssa Bragg, Alexis Stubblefield, Edgar Castro, Chase Newby

Abstract:

INTRODUCTION: Quadricep inhibition, failure of voluntary activation of the quadriceps, is seen in patients after knee surgery (Snyder-Mackler 1994). The cause of quadricep inhibition is not yet known, but it can lead to osteoarthritis (Lepley 2015). Quadricep inhibition should be studied to provide potential information on prevention of inhibition caused by various knee injuries, like the common torn ACL. The Biodex has been used in previous studies (Anderson 2012) to conduct a valid and reliable evaluation of the forces and strength of each leg.

PURPOSE: The purpose of the study was to gather observational data on patients with a history of knee surgery within two years (short-term) or longer than two years (long-term) in relation to strength measured by torque. The null hypothesis was that there is no significant difference in the deficit of quadriceps strength post-surgery in short-term compared to long term.

METHOD: 12 subjects participated in this study (both male and female); age 18-35. Subjects were separated into groups based on time after surgery. Group 1: short-term (2 years or less post-op). Group 2: long-term (>2 years post-op). Criteria was only one knee with surgery along with no injuries to the back, hip, or other leg. Subjects filled out given paperwork, then were positioned on the Biodex and fitted for proper testing based on individual's morphology. Subject performed warm-up leg extensions and flexions. Test was set at 180 d/s for strength quantification. Test was performed on unaffected leg first (control). Subject was then released from Biodex and given results of test.

RESULTS: The average torque for the uninvolved knees was 87.98 Â± 26.18 Nâˆ™m. The average torque for the involved knees was 79.06 Â± 20.96 Nâˆ™m. With a deficit defined as 10 percent; less than or equal to two years post-surgery averaged 19.85 Â± 12.27 % for having deficits. Greater than two years averaged 3.45 Â± 23.79 % (F[1,10] = 2.252, p = 0.164).

CONCLUSION: 4 out of the 6 subjects in group 1 (â‰¤ 2 years) had deficits, while 2 out of the 6 subjects in group 2 (> 2 years) had deficits. The group with the shorter time post-surgery had a greater percentage of individuals with a deficit compared to the longer term group. However, data showed that values were not met for it to be significant. The null hypothesis stating that there is no significant difference in the deficit of quadricep strength post-surgery in short term compared to long term was accepted.

Poster Number: 82


Motor, but not cognitive ability, is associated to movement imagery capacity in children

Presenter: Chadwick Fuchs, Kinesiology Graduate Student

Mentor: Dr. Priscila Cacola

Abstract:

Motor imagery provides a unique window on the integrity of movement representation. While it is somewhat established that motor imagery abilities are formed by age seven, little is known about the contribution of motor and cognitive abilities in this capacity. When looking at kinesthetic and visual modalities, it is known that children rate the kinesthetic modality as the most difficult imagery task to perform, while the external visual imagery is the easiest. Therefore, the aim of the present study was to evaluate whether movement components of imagery capacity could be distinguished by differences in motor and cognitive ability. Using the Movement Imagery Questionnaire for Children (MIQ-c); a questionnaire developed for children, thirty-eight children with ages between 7 and 12 years were tested with the Movement Assessment Battery for Children, 2nd edition (MABC-2), Kaufmann Brief Intelligence Test, 2nd edition (KBIT-2), and the MIQ-C. A one-way ANOVA was conducted for each one of the capacities for three levels of motor and two levels of cognitive ability, determining that lower levels of motor capacity (< 5th percentile) were associated with lower scores on kinesthetic imagery (p = .05). Pearson correlation analysis revealed a moderate relationship between kinesthetic imagery and manual dexterity (r= .45) and with total motor ability (r= .32). Results indicated that individuals with high motor ability are also high in their kinesthetic imagery ability, as compared to their internal and external visual imagery. However, this could be due to the fact that the children performed the simple movement tasks prior to being asked to image the movement. Further exploration of the involvement of cognitive and motor abilities and how they interact to promote movement imagery is warranted. Future studies will be directed towards using kinesthetic imagery as a therapeutic modality for children with developmental motor cognition disorder.

Poster Number: 83


Novel, Bone-like Ossified Particles in the Peripheral Circulation of Male Fischer-344 Rats Across the Lifespan

Presenter: Seungyong Lee, Kinesiology Graduate Student

Mentor: Dr. Rhonda D. Prisby

Group Members: Sophie Guderian

Abstract:

BACKGROUND: We previously reported bone marrow blood vessel [BMBV] ossification (i.e., the conversion of bone marrow blood vessels into bone) across the lifespan in male Fischer-344 rats (Prisby, 2014; Guderian, ASBMR 2015). Augmented BMBV ossification at 24 months coincided with reduced trabecular bone volume and several hematological parameters (i.e., RBC, Hgb, Hct and %LY). Further, examination of ossified BMBV under ultra-high magnification revealed the presence of presumed ossified particles (OSP) at the abluminal and luminal surfaces. PURPOSE: We sought to assess whether OSP were present in the peripheral circulation. METHODS: Ventricular whole blood samples were collected from male Fischer-344 rats (1-mon, n=4; 12-mon, n=4 and 24-mon, n=5) and processed to identify OSP. OSP were quantified and sorted with a BD FACSAria II flow cytometer. Sorted particles were subsequently imaged with confocal and scanning electron microscopy. The composition of OSP were determined via elemental analysis. OSP diameter and size distribution were assessed from 2 rats per group utilizing SEM microphotographs and Image J. RESULTS: Body mass (p<0.05) increased with age between 1- and 12-mon. OSP were observed at all ages (1-mon, 2283Â±511 per 500 ÂµL; 12-mon 7922Â±1905 per 500 ÂµL and 24-mon 3181Â±997 per 500 ÂµL), peaking at 12-mon (p<0.05 vs. 1-mon and 24-mon). The diameters of OSP ranged from 1â€“30Âµm (1-mon), 1-33Âµm (12-mon) and 1-16Âµm (24-mon). The frequency of OSP ranging in diameter from 0-5Âµm (1-mon, 32; 12-mon, 32; and 24-mon, 61), 5-10Âµm (1-mon, 4; 12-mon, 13; and 24-mon, 7) and 10-15 Âµm (1-mon, 2; 12-mon, 5; and 24-mon, 3) were similar among groups. OSP > 15 Âµm were observed at all ages (1-mon, 2; 12-mon, 4; and 24-mon, 1). OSP contained calcium as assessed via elemental analysis and, morphologically, some OSP had rough and jagged edges. Extrapolated values of OSP count in the circulation according to an average blood volume for a rat (i.e., 64ml/kg BW) are ~45,000 (1-mon), ~428,000 (12-mon) and ~162,000 (24-mon). CONCLUSION: This is the first report of bone-like particles in the peripheral circulation of rats. OSP > 15 mm may serve as emboli to small blood vessels, increasing the risk of blockage. At minimum, the rough morphology of OSP may contribute to damage of the endothelial cell lining. Finally, circulating OSP may contribute to ectopic bone formation if they gain access to soft peripheral tissues.

Afternoon Session Posters

1:30-3:30

College of Architecture, Planning and Public Affairs

College of Engineering

College of Liberal Arts

Poster Number: 9

Bluebonnet Ballroom, Afternoon Session, 1:30 PM to 3:30PM

Developing a Discipline-Based Comparative Assessment Model for Measuring Legacy Space Program’s Knowledge Contribution

Presenter: Loveneesh Rana, Aerospace Engineering Graduate Student

Mentor: Bernd Chudoba

Abstract:

Goal: Aerospace history is filled with canceled programs where a huge amount of research effort was invested in developing the state-of-art technology. Unfortunately, a framework is missing that could quantitatively identify, specifically where, and how much effort was invested, and in what particular disciplines. This research introduces a prototype approach to capturing the knowledge gained during legacy space programs by developing a quantitative framework, to assess, identify, and compare the disciplinary contribution and overall importance of selected case-studies. In addition to the discipline-oriented assessment, a design-oriented review is also conducted to measure the significance and overall impact of design synthesis on the program. This step further highlights how design discipline is mostly undocumented in most of these legacy programs, an irony to the fact that the discipline-oriented decisions are made based on design synthesis results.

Process: Lifting Reentry Vehicle (LRV) is selected as the class of vehicle to implement the quantitative assessment model. Sixty case-study LRV programs are assessed through this framework on the basis of contributions made towards major hypersonic disciplines. The Analytical Hierarchy Process (AHP) is used to develop an analytical model, to quantify and measure the strengths and weaknesses of primary disciplines for every case study. These case-studies are evaluated based on discipline-based criteria(aerothermodynamics, structure & materials, propulsion, thermal, and sub-system), and systems-based criteria addressing the life-cycle stage of the program (i.e. paper study, test vehicles, operational vehicles etc). The AHP model is then used to conduct a comparative assessment among the case-studies based on quantitative results, which identify a case study's value and contribution to the growth of the primary disciplines, and the evolution of the overall hypersonic knowledge base. Following the discipline-based analysis, a synthesis-oriented survey is conducted where legacy programs are assessed for the integrated design synthesis effect. Several factors are considered measuring the information available on the multi-disciplinary logic, and integrated disciplinary aspects for each case-study. This is done to understand the level of design synthesis effort made and documented in contrast to discipline-specific contribution. This analysis is conducted to demonstrate the analysis-strong, synthesis-weak trend.

Poster Number: 10


Photoluminiscent-Polylactones Based Nanoscaffolds

Presenter: Aneetta Kuriakose, Bioengineering Graduate Student

Mentor: Kytai T. Nguyen

Group Members: Priyesh Rajnikant, Upasana Mali, Dingying Shan, Liping Tang, Subhash Banerjee, Jian Yang

Abstract:

Percutaneous coronary intervention (PCI) is commonly employed for revascularization. These strategies, however, injure the arterial wall initiating a cascade of inflammatory responses that culminates in restenosis. In our research work, we proposed to use a platelet mimicking fluorescent nano-scaffold system that can cloak an injured artery site from inflammatory cells, capture the endothelial progenitor cells (EPC) using specialized targeting agents, and promote in situ endothelial regeneration. We used photo-luminescent polylactone copolymers such as BPLP-co-poly(L-lactide) (BPLP-PLLA) and BPLP-co-poly(lactic-co-glycolic) acid (BPLP-PLGA50:50 and BPLP-PLGA75:25) to prepare nanoscaffolds; their intrinsic fluorescent properties help us localize and monitor the scaffoldâ€™s degradation in vivo as endothelial regeneration ensues. Our initial studies were focused on optimizing a suitable polymer to be used to make a novel nano-scaffold system.

We fabricated uniformly distributed ~200 nm sized BSA-loaded BPLP-polylactone based nanoparticles (NPs) by standard double emulsion method. BPLP-PLGA based particles released BSA within 14 days, however, BPLP-PLLA showed slow and continued release for 28 days. BPLP-PLGA degraded completely within 4 weeks of study, whereas BPLP-PLLA degraded only 20% during the same time. The cyto-compatibility study showed that the BPLP-PLGA 50:50, especially at high concentrations (> 1000 ï�-g/ml), is significantly toxic to the human umbilical vein endothelial cells (HUVEC); however, no such toxicity was observed for BPLP-PLGA 75:25 and BPLP-PLLA. Hemo-compatibility of the particles demonstrated that they didn't cause any significant lysis of red blood cells, and neither affected blood clotting kinetics compared to that of the control. Furthermore, we observed a minimal number of platelet attachment and activation on BPLP-PLGA films compared to that of the positive control (glass surface). Based on these initial results we selected BPLP-PLGA 75:25 to fabricate nanoscaffolds. Currently, we are optimizing the effective particle size to enhance their margination towards the arterial wall and other factors, including specialized capturing agents to capture EPC, and growth factor cocktail to improve EPC homing and differentiation at the injured site.

Poster Number: 11


Detection of Molecular Markers Which Stimulate EMT and Migration in Cells

Presenter: Tamara Hill, Bioengineering Graduate Student

Mentor: Young-tae Kim

Group Members: Loan Bui, Sayem H. Bhuiyan, Rami Barakat, Sandra Rose Miller, Viviana Isabel Casas Iberico

Abstract:

Detection of Molecular Markers Which Stimulate EMT and Migration in Cells

Tamara Hill, Loan Bui, Sayem H. Bhuiyan, Rami Barakat, Sandra Rose Miller, Viviana Isabel Casas Iberico and Young-tae Kim

Breast cancer comprises one of the largest cancer groups in the United States and its metastasis leads to more deaths than many other diseases. Treatment often includes chemotherapy, radiation, and tumor excision. However, the pitfalls that accompany these treatments include inability to efficiently target and destroy residual and migrating cells. Because these are the cells which are typically the cause of end stage mortality, they have been the target of many studies to determine molecular events which lead to their ability to dissociate from a primary tumor and invade the circulation and other tissues. Many studies have utilized the pitri dish to study migrating cancer cells. However, this method neglects to stimulate molecular, genetic, proteomic, and cell surface changes the cells naturally undergo which enable migration to sites distant from the primary tumor. We have designed a microchannel device which simulates the 3D microenvironment a malignant migrating cell travels, enabling molecular expression which we can detect, analyze, and possibly use in the design of clinical targets. This device facilitates 3D migration of MB-231, an aggressive line of breast cancer cells, and subsequent collection of these cells in substantial quantities. It has also facilitated the spatial differentiation of breast cancer cells grown in the 2D environment vs. those grown in the microchannels. This has allowed for the detection and analysis of changes in the expression levels of proteins which impart to the cell the ability to undergo a transition from an epithelial to a mesenchymal phenotype.

Poster Number: 12


Characterization of Various Changes in Biomolecules of Cells during Their Migration in Physical Confinement

Presenter: Loan Bui, Bioengineering Graduate Student

Mentor: Young-Tae Kim

Group Members: Tamara Hill, Sayem H Bhuiyan, Qionghua Shen, Vanessa Saavedra, Calvin Kong and Young-tae Kim

Abstract:

Cancer metastasis is a leading cause of death due to the trouble of single cells escaping from primary cancer and invading distant sites. Current cancer research has focused on the migrating capabilities of these aberrant cells. In most in vitro studies, the cells were cultured on traditional petri dishes (2D culture). As concerns have been raised regarding the possible lack of invasive characteristics of cells collected from 2D culture, many researchers have shifted to three-dimensional (3D) culture of cancer cells. However, retrieving large amounts of cells during their migration and/or separating them from 3D environments become the major challenges that limit many experimental quantifications including those for DNA, RNA and protein analysis. This drawback might lead to a lack of understanding key features of cancer metastasis. We hereby developed a microchannel device which facilitated the collection of cells during their migration in 3D physical confinements. Subsequently, we would be able to perform further bio-molecular studies. Each device consisted of multiple microchannels providing enough space to house a significant number of migrating cells. Cells were introduced and allowed enough time to migrate through the microchannels. Once cells had occupied the majority of microchannel areas, the device was easily isolated for migrating cell collection. Using G55, an aggressive brain cancer cell line, we were able to quantify the expression of numerous biomarkers from migrating cells such as Î²III Tubulin. Showing the differences in biomarker expression between migrating cells and cells seeded on 2D would elucidate more unknown features of cancer metastasis. The technique was simple but showed novel quantification capabilities in migrating cancer cells, making it a promising tool for cancer study.

Poster Number: 13


Glutathione-Sensitive Nanoparticles as Drug Delivery Vehicles for Lung Cancer Therapy

Presenter: Dona Padanilam, Bioengineering Graduate Student

Mentor: Dr. Kytai T. Nguyen

Group Members: Roshni Iyer, Daria Zhukova, Cancan Xu, Yi Hong

Abstract:

According to the American Cancer Society, an estimated 1 out of 4 cancer deaths attributes to lung cancer. Current lung cancer therapies like chemotherapy or radiotherapy have limitations such as cytotoxicity to healthy cells. Targeted delivery of anticancer drugs to tumor sites via stimuli-responsive nanoparticles (NPs) can increase their therapeutic efficacy and safety. We have successfully formulated Glutathione (GSH)-sensitive NPs, using a novel GSH-cleavable polymer containing disulfide bonds, which degrades in response to elevated GSH levels in cancer cells. These nanoparticles were loaded with Cisplatin, an anticancer drug, characterized and evaluated for in vitro therapeutic improvement.

The GSH sensitive NPs displayed an average size of 245 Â± 19.55 nm, and a surface charge of -12.13 Â± 2.20 mV. NPs exposed to 10 mM GSH showed 76%, 41%, and 16% increase compared to 0, 2 and 5 mM GSH respectively, indicating their stimuli responsive behavior. The cytocompatibility results with bare (drug-free) nanoparticles observed more than 85% cell viability to AT1 cells (healthy cells) upto 500 ug/mL, hemolysis of less than 0.07% and blood clotting patterns similar to that of the saline control. The NP uptake results displayed a concentration dependent increase in NP uptake into lung cancer cells. Additionally, the Cisplatin-loaded NPs caused more cancer cell death than the free Cisplatin of similar doses (91 % vs. 53% cell death, respectively).

Based on these results, GSH-NPs could potentially be used for on-demand drug release for lung cancer therapy.

Poster Number: 14


Demyelination in the Pediatric Spinal Cord Detected with Magnetization Transfer Imaging Ratio

Presenter: Meghana Hosahalli Shivananda Murthy, Bioengineering Graduate Student

Mentor: Georgios Alexandrakis

Abstract:

Transverse myelitis is an inflammatory syndrome of the spinal cord. It causes demyelination of nerve fibers in the nervous system. Approximately 1,400 cases of transverse myelitis per year are reported in the United States and 20% occur in children. The prognosis of transverse myelitis in children is unclear and it may lead to paralysis if untreated. Routine MRI has been the common diagnostic technique however, studies have shown it to have poor correlation with the clinical status of myelitis patients. Therefore, combining MRI with an independent measure that is sensitive to demyelination such as Magnetization Transfer Ratio (MTR) would increase reliability of diagnosis. We hypothesize that children with myelitis will show different MTR values then healthy controls.

One patient with myelitis and one healthy control were recruited for the study. To examine reliability of our technique, each subject was scanned twice using MRI system. A MATLAB code was developed to calculate mean MTR values. Patient with transverse myelitis showed lower MTR values in comparison to healthy controls. From the statistical analysis, significant differences (p<0.0001) were observed between mean MTR of patient and control. Reliability tests showed strong agreement in MTR values between two scans. Our results are in agreement with published data in the spinal cord of children and adults with demyelinating disorders.

Our results provide strong evidence that MTR could be a potential imaging biomarker to characterize the extent of myelin loss. This imaging technique can be used to assess other demyelinating disorders such as encephalomyelitis, multiple sclerosis (MS).

Poster Number: 15


CHANGES IN RESTING STATE MRI NETWORKS FROM A SINGLE SEASON OF FOOTBALL DISTINGUISHES CONTROLS, LOW, AND HIGH HEAD IMPACT EXPOSURE

Presenter: Gowtham Krishnan Murugesan, Bioengineering Graduate Student

Mentor: Dr. Albert Montillo

Abstract:

Sub-concussive asymptomatic head impacts during contact sports may develop potential neurological changes and may have accumulative effect through repetitive occurrences in contact sports like American football. The effects of sub-concussive head impacts on the functional connectivity of the brain are still unclear with no conclusive results yet presented. Although various studies have been performed on the topic, they have yielded mixed results with some concluding that sub concussive head impacts do not have any effect on functional connectivity, while others concluding that there are acute to chronic effects. The purpose of this study is to determine whether there is an effect on the functional connectivity of the brain from repetitive sub concussive head impacts. First, we applied a model free group ICA based intrinsic network selection to consider the relationship between all voxels while avoiding an arbitrary choice of seed selection. Second, unlike most other studies, we have utilized the default mode network along with other extracted intrinsic networks for classification. Third, we systematically tested multiple supervised machine learning classification algorithms to predict whether a player was a non-contact sports youth player, a contact sports player with low levels of cumulative biomechanical force impacts, or one with high levels of exposure. The 10-fold cross validation results show robust classification between the groups with accuracy up to 78% establishing the potential of data driven approaches coupled with machine learning to study connectivity changes in youth football players. This work adds to the growing body of evidence that there are detectable changes in brain signature from playing a single season of contact sports.

Poster Number: 16


Synthesis Parameters Influencing the Size of Biodegradable Hyaluronic Acid Nanoparticles

Presenter: Daniya Umer, Bioengineering Graduate Student

Mentor: Dr. Kytai Nguyen

Group Members: Matthew Muir, Roshni Iyer

Abstract:

Nanoparticles (NPs) made from hyaluronic acid (HA) have demonstrated their tremendous potential as drug carriers for cancer therapy. HA expresses an anti-CD-44 ligand, capable of specifically binding to the CD44 receptor often expressed on various cancer cells. It has been well-known that NP size has dramatic effects on the efficacy of drug carriers due to the capacity to cross biological barriers and to be up-taken by cancer cells. However, little has been done to extensively investigate factors affecting HA NPs. In this study, varied synthesis parameters influencing the HA NP size were studied in efforts to optimize the NP size. A relationship between NP size and synthesis parameters, including HA concentration, oil to water ratio, sonication power, and swelling time was quantified using Design Expert software. The predicted equation for any interested NP size was also generated. It was found that sonication power and HA concentration significantly affected the NP size. Based on the predicted equation, we performed an experiment to validate our formulation model. The model predicted a NP size of 89 nm with a certain formula; the actual size achieved from using that formula was 91Â±38 nm, a less than 2.25% error between the predicted and actual sizes. We successfully minimized the size of HA NPs by altering synthesis parameters and used our predictive model to formulate NPs of less than 100nm. The predictive model developed in this study can be used in further studies to formulate small NPs to carry therapeutic agents to treat cancers.

Poster Number: 17


Enzymatic Responsive Nanoparticles for Targeting Breast Cancer in vitro

Presenter: Hien Lam, Bioengineering Graduate Student

Mentor: Kytai Truong Nguyen

Group Members: Duong Q. Le, Tram N.H. Vo

Abstract:

Many nanoscale anticancer drug delivery systems have faced several limitations, including their low tumor-targeting ability and high toxicity to nearby healthy organs. Herein, we developed a new enzyme-responsive nanoparticles (NPs) from amphiphilic copolymer hyaluronic acid-co-poly (D, L-lactic acid) (HA/PLA). The NPs has core-shell structure with the HA shells specifically target to CD44 receptors overexpressed on MDA-MB-231 human breast cancer cell lines and selectively degraded by hyaluronidase enzyme (HAase) overabundant at solid tumors. PLA/HA copolymer was synthesized via ring opening polymerization, and NPs were formulated by a standard emulsion method. The structure of HA/PLA NPs and their enzyme-triggered degradation were confirmed by Fourier Transform Infrared Spectroscopy and degradation studies with different concentrations of enzymes, respectively. The mean diameter of PLA/HA was about 200nm. PLA/HA NPs were hemo- and cyto-compatible up to a concentration of 0.5 mg/ml using human blood and cell cultures, respectively. An anticancer drug, Doxorubicin (DOX), was loaded on PLA/HA NPs by a double emulsion method with a loading efficiency of 30%. These NPs (Dox-PLA/HA NPs) possessed an enzyme-responsive release profiles in response to different concentrations of HAse. Cell viability studies of DOX-PLA/HA NPs on human dermal fibroblasts showed that these NPs significantly reduced cell toxicity compared to that of free DOX. On the other hand, the therapeutic performance of these NPs on MDA-MB-231 presented a higher cell death under appearance of HAse in comparison to non-enzyme conditions. These enzymatic-responsive NPs exhibited as a promising carrier for treatments of breast cancers.

Poster Number: 18


Improving Hydrogel Drug Release Properties Using Niosomal Nano-Vesicles

Presenter: Tyrell Pruitt, Bioengineering Graduate Student

Mentor: Kytai Nguyen

Group Members: Kubra Cetiner, Amirhossein Hakamivala, Boris Rodionov

Abstract:

Nanostructure drug release systems are designed for the delivery of loaded drugs to promote permeation across biological membranes and can target absorption sites to enhance pharmacological potency. Nano-scale drug delivery systems like hydrogel and niosomes are remarkable candidates for the delivery of these various therapeutic agents. Niosomes are synthesized by non-ionic surfactants, which generate a structure similar to liposomes but without charge interference. Due to this unique characteristic the niosomes can be loaded with both hydrophilic and lipophilic drugs. Hydrogel is also a preferred material for designing nanoparticles and provide controlled release applications thanks to its 100 percent loading efficiency, extended release rates of drugs, its biodegradability, and its biocompatibility. However these individual methods have never been combined into a single drug delivery system. Therefore, this study was conducted to characterize a combined niosome-hydrogel system as thoroughly as possible. First, hydrophilic drug analog Bovine serum albumin (BSA) loaded niosomes were embedded into alginate hydrogel beads. The beads were then characterized for particle size, zeta potential, polydispersity, stability, entrapment efficiency (EE), and morphology. Release behavior and cytotoxicity of these nanoparticles was also evaluated. Results showed the niosome embedded alginate beads exhibited no cytotoxicity towards 3T3 fibroblast cells and BSA loaded niosomal-alginate beads improved drug release duration without negatively effecting any other properties. Future research is needed to find the optimal niosome to hydrogel ratios and targeting methods for various therapeutic applications.

Poster Number: 19


Up-regulation of cerebral cytochrome-c-oxidase and hemodynamics by transcranial infrared laser stimulation: A broadband near-infrared spectroscopy study

Presenter: Sahil Sunil Nalawade, Bioengineering Graduate Student

Mentor: Dr. Hanli Liu

Group Members: Xinlong Wang, Fenghua tian, Divya Reddy

Abstract:

A non-invasive form of photo biomodulation is the technique used for Transcranial infrared laser stimulation (TILS). Cytochrome-c-oxidase (CCO) is the enzyme, which results as the terminal enzyme in the electron transport chain occurring in the mitochondria. Thus, we hypothesize it to be the primary intracellular photo acceptor. We also hypothesize that hemodynamic changes and regulation of Cerebral CCO is caused by TILS. 1064 nm Laser stimulation is used to stimulate on the healthy subjects, also near-infrared broadband spectroscopy was used to receive light reflectance from treated cortical area prior, during and later TILS. Experiments were of two type TILS and Placebo and a comparison between the two was done to have an accurate correlation. The data taken from the spectroscopic readings was analyzed and modified Beer-Lambert law was used to fit the parameters. Thus after comparison we observed that there is a considerable rise in the cerebral concentration of oxidized CCO [CCO], >0.08 mM, P<0.01, oxygenated Hemoglobin [HbO], >0.8, P<0.01 and total hemoglobin [HbT], 0.5 mM, P < 0.01 during and after Transcranial infrared laser stimulation, and also there is a linear relation between [CCO] versus [HbO] and between [CCO] versus [HbT]. Thus, this study shows the first observation that TILS shows up-regulation of oxidized CCO in the brain. Thus it contributes critical insights into the physiological system.

Poster Number: 20


P-Cone: A Novel Cone Penetration Test Device for Deep Foundation Design

Presenter: Hai Nguyen, Civil Engineering Graduate Student

Mentor: Dr. Anand J. Puppala

Abstract:

A major difficulty with current cone penetration test devices (CPTU) is that the limited reaction force prevents the sounding from reaching into the depth at which the piles are usually installed. To eliminate this restriction, a novel cone penetration test device, the P-cone, has been developed to assist in pile design by combining features of CPTU cone sounding and bidirectional loading. The P-cone is used in combination with a hydraulic jack that serves as the movement-and-force-generating essential feature. The penetration depth is improved by employing the pressure in a cell, that uses the cone rods and surface anchors on the ground as a reaction, to push the cone down. Using two independent systems, the P cone measures shear stresses versus movements and penetration stresses versus movements of the in situ soil at desired depths. The in-situ soil test results obtained from the P-cone are particularly useful for evaluating the bearing capacity and the long-term settlement of piled foundations.

Poster Number: 21


Design and Demand Estimation of a Bus Transportation System for City of Arlington

Presenter: Sirwan Shahooei, Civil Engineering Graduate Student

Mentor: Dr. Sia Ardekani

Abstract:

Bus transit system is one of the major modes of transportation in urban areas. With proper planning and operation, bus transit systems can provide fast and convenient service to and from work, shopping centers, and entertainment destinations. Launching a bus transit system will provide multiple benefits to a city including reduction in traffic congestion, decreasing air pollution, and reducing fuel consumption.

City of Arlington is known as the largest city in nation that does not have local transit system. Voters in City of Arlington have rejected transit proposals three times. Opponents of bus transit system mostly argue that Arlington is a low-density city and a public transit system is not economically feasible.

The purpose of this paper is to provide a design for a local bus transit system in Central area of the city of Arlington. This research also aims in estimating the potential annual ridership for the proposed system in order to find out if the designated bus system is justifiable. GIS software is used for analysis and modeling of socio-spatial data in tract scale.

Based on system configuration, the capacity analysis reveals that the system will have 994,115 passengers/year Throughput. Calculations from demand model shows that the designated transit system will have 754,200 passengers /year. The results of the study shows that the Arlington Central area provides enough ridership to support a local bus transit system.

Key words: Transit Planning, Public transportation, Demand Modelling, GIS, City of Arlington

Poster Number: 22


Development of landfill biocovers from yard waste to oxidize methane escaping from landfills

Presenter: Gomathy Radhakrishna Iyer, Civil Engineering Graduate Student

Mentor: Dr. Melanie L.Sattler

Abstract:

When microorganisms degrade organic waste in landfills under anaerobic conditions, they produce landfill gas, which is about 50% methane and 50% carbon dioxide. Although both methane and carbon dioxide are greenhouse gases, methane is 28 times more potent. The contribution of landfills to climate change can be reduced by using innovative landfill cover materials which oxidize methane to the less-potent carbon dioxide. Biocovers, which are biologically active landfill covers, are one such innovative type of cover. Although compost has been tested as a biocover material, fresh yard waste has not. Since yard waste constitutes 13% of the US waste stream, finding beneficial uses for it is important. This study was thus conducted to investigate whether fresh yard waste by itself, or along with biosolids and fly ash, can enhance methane oxidation in landfill covers. Physical and chemical parameters of yard waste, biosolids, and fly ash were determined. Aerobic batch reactors were then set up to quantify the methane oxidation capacity of grass clippings, leaves, biosolids and fly ash individually and in combination to form different carbon/nitrogen (C/N) ratios. The highest biocover performance indexes were exhibited by 1) leaves by themselves (1.39 Î¼g of methane oxidized per g of biocover material per hr), 2) a mixture of grass clippings and biosolids with a C/N ratio of 12 (1.24 Î¼g/g/hr), and 3) glass clippings by themselves (1.13 Î¼g/g/hr). However, fly ash by itself did not contribute to methane oxidation.

Poster Number: 23


Effect of Termite Gut microbe (TAV5) on methane generation from degradation of municipal solid waste.

Presenter: Hoda Rahimi, Civil Engineering Graduate Student

Mentor: Dr Melanie Sattler

Abstract:

Methane from anaerobic processes is being increasingly utilized as an alternative energy source in developed countries, via large projects that extract methane from landfills or wastewater treatment plants. Anaerobic degradation of organic material (biomass) involves decomposition by bacteria under humid conditions without any oxygen. Organic carbon deposited in landfills is converted by microbes to carbon dioxide (CO2) and methane (CH4). If the methane is not captured, it contributes to climate change (25 times more effectively than CO2 on a per-mass basis). If the methane is captured, it can be used as a renewable energy resource. Lignocellulose comprises 40-70% of municipal solid waste (MSW) in developed countries, including paper, wood, yard waste, and textiles such as cotton fibers. The major degradable constituents of lignocellulose - cellulose and hemicellulose - are often shielded by lignin. Lignin is unfortunately resistant to microbial degradation under anaerobic conditions that normally occur in MSW landfills. Termites have long been recognized for their ability to consume lignocellulosic plant material and soil (humus).The objective of the current study was to determine the effect of a specific kind of microbe from termite hindgut, TAV5 (Termite Associated Verrucomicrobia), in a mixed culture on accelerating MSW decomposition rate and methane gas generation. Reactors seeded with consortia that included TAV5 generated 62%, 71%, and 2% more methane from paper, yard, and wood waste, respectively, under conditions of 1-2% oxygen compared to reactors seeded with anaerobic digester microbes only at 38Â°C after 180 days.

Poster Number: 24


Preference Aware Time Sensitive Travel Route Recommendation

Presenter: Madhuri Debnath, Computer Science Engineering Graduate Student

Mentor: Ramez Elmasri

Abstract:

There have been vast advances and rapid growth in Location based social networking (LBSN) services in recent years. A user post his presence or arrival to a physical location, also known as Point of Interests (POIs). The process is known as "Check-in". The availability of such information open up an array of new research problems and various real world applications. Travel Route recommendation system is the example of such real world applications.

Traveling is one of the most important entertainment in the modern society. Traveling in an unfamiliar city requires a good knowledge about the interesting and popular attractions of that city. Also the movement sequence from one location to another location should be planned effectively so that it maximizes user happiness in a specific time budget constraint.

Travel route recommendation provides users a sequence of POIs (Point of Interests) as a route to visit. In this work, we propose to recommend time-aware and preference-aware travel routes consisting of a sequence of POI locations with corresponding timestamps. It helps users not only to explore interesting locations in a new city, but also it will help to plan the trip accordingly with those locations with timestamp information in a specific time constraint. First, we find the interesting POI locations that considers the following factors: User's categorical preferences, temporal activities and popularity of location. Then, we propose an efficient solution to generate travel routes with those locations. This travel routes will tell users where to visit and when to visit. We evaluate the efficiency and effectiveness of our solution on a real life LBSN dataset.

Poster Number: 25


“Make Twitter Great again!”: A text analysis of Donald Trump’s tweets

Presenter: Xiaolei Ren, Computer Science Engineering Graduate Student

Mentor: Chyng-Yang Jang

Group Members: Zedan Xu

Abstract:

Donald Trump's unexpected victory in the United States presidential election of 2016 has put the political analysts and opinion polls to a stiff test. Twitter was considered an impact indicator that had played an important role throughout the 2016 presidential election. With almost 25 million followers on Twitter, Donald Trump would often start his own news cycles with deeply opinionated and often incendiary posts. This study attempts to examine if his tweets contributed to the triumph of the 2016 presidential election by analyzing the frequency and content of his tweets during the 2016 presidential campaigns. In order to understand his Twitter behavior and personality, this study focuses on the structures and dissemination of his tweet rhetoric in terms of vocabulary, grammar, and punctuations. The computational method of Web Crawler is employed to extract and collect Donald Trump's tweets posted on Twitter between June 16, 2015, and Jan 20, 2017, from his personal Twitter account. From the theoretical framework of persuasion and propaganda, this study aims to investigate how Donald Trump used his tweets to gain media attention and shape public opinion and therefore, to understand how Twitter contributed to his political rise.

Poster Number: 26


Flexible and bendable MEMS accelerometer fabricated using double UV-LIGA process

Presenter: Md Sohel Mahmood, Electrical Engineering Graduate Student

Mentor: Dr. Zeynep Celik-Butler

Abstract:

MEMS accelerometers have various sensing applications including wearable industry, biosensors, electronic display etc. The miniaturization and large scale commercialization of the devices has been possible for the unprecedented development of micro-electro mechanical system (MEMS) technology. Recent development of MEMS devices incorporates the possibility of bending when fabricated on flexible substrate. Design, fabrication process and characterization of conformal accelerometers are presented here. Three different geometries of accelerometers were designed in CoventorwareÂ® software having size of 640ÂµmÃ—640Âµm, 720ÂµmÃ—720Âµm and 960ÂµmÃ—960Âµm. These devices were fabricated on polyimide substrate to facilitate the bending. The maximum bending radius of curvature varies between 1 cm to 2 cm ensuring total compatibility of mounting on human hand. The devices can be mounted on robotic or prosthetic fingertips since the radii of robotic fingertips of the index finger and thumb are 1.0 cm and 3.5 cm respectively. Besides robotics or prosthetics, these bendable devices can be utilized with high proficiency in game controllers, collision recognition, human motion monitoring system etc. The novelty of this work lies in the double UV-LIGA fabrication process where two layers of proof mass system was deployed in accelerometer. To maintain the integrity of the polyimide layers, low temperature fabrication process was followed. Sensitivity as high as 194 fF/g was observed during characterization which demonstrates a six-fold increase in sensitivity compared to the state-of-the-art.

Poster Number: 27


Lung Nodule Detection and Segmentation Using a Patch-Based Multi-Atlas Method

Presenter: Mustafa Alam, Electrical Engineering Graduate Student

Mentor: Venkat Devarajan

Abstract:

CT image based lung nodule detection is the most widely used and accepted method for detecting lung cancer. Most CT image based methods are based on supervised/unsupervised learning, which has a high number of false positives and needs a large amount pre-segmented training samples. This problem can be solved, if a set of optimally small number of training samples can be created, where each sample has lung nodules of similar size and shape as the target image of the actual patient. Based on this hypothesis, we propose a novel patch-based multi-atlas method with three main steps: a) a small set of atlases is selected by comparing the target image with a larger set of atlas images using a size-shape based feature vector, b) lung nodules are selected using a patch-based method, where each pixel of a target image is labelled by comparing the image patch, centered by the pixel with patches from an atlas library and choosing the most probable labels according to a defined closest match criterion and c) a Laplacian of Gaussian blob detection method is used to find the segmented area of the lung nodule. We tested the method with more than 5 test images, where each test image is applied to more than 200 atlas images. For non-attached nodules in the size between 3 mm to 30 mm, the sensitivity of the proposed algorithm is 100%.

Poster Number: 28


Predicting a Quarterback's Fantasy Football Point Output for Daily Fantasy Sports using Statistical Models

Presenter: Nicholas King, Industrial, Manufacturing and Systems Engineering Graduate Student

Mentor: Dr. Aera LeBoulluec

Abstract:

In the new age of daily fantasy sports (DFS), fantasy football has become an enormous revenue generator for DFS sites, such as DraftKings and FanDuel. Both companies are valued over \$1 billion. However, previous analysis done by popular DFS site Rotogrinders, has shown that only the top players are consistently winning, the top 10 players much more frequently than the remaining 20,000 players. Using complex statistical models they're able to identify top athletes and value picks (based on an athlete's draft 'salary') that the average player might not be aware of.

There is a need to evaluate which methods and algorithms are best at predicting fantasy football point output. These methods could then be applied to future DFS contests outside of football to see if they predict other fantasy sports point output well. There is little literature and few resources available on this subject. Several factors contribute to this. Daily Fantasy Sports are still relatively new, and many people are still just starting to get involved in them. Also, very few people have published their work on their custom models or significant variables, since they are generally developing these models for personal use in an attempt to gain an edge in DFS and win money. Thus, there is little to no motivation to make their research or methods publicly available.

This research will attempt to predict the weekly point output of a quarterback based on a variety of attributes and metrics. Finding the important variables and statistical models and learning how to address the volatility in week-to-week performances for a quarterback will allow us to expand this to other player positions in the future. In addition to understanding the best algorithms to apply to weekly point prediction and the best variables to use to predict a quarterback's output, this research also seeks to answer the question that is a currently being debated in courtrooms across the country - should DFS be considered a legal game of skill, or a game of luck, and therefore online gambling?

Poster Number: 29


Productivity improvement and cost optimization of small scale enterprises using simulation

Presenter: Unmesh Vishwas Tamhankar, Industrial, Manufacturing and Systems Engineering Graduate Student

Mentor: Dr. Aera Leboulluec

Abstract:

Productivity increase and cost optimization are critical tasks for small scale industries. In a competitive environment, increasing productivity without installing additional capacity enables small scale industries to avoid heavy investment and maximize their profitability. In this research, the objectives were accomplished in three stages. In the first stage, a detailed time study was conducted to understand the working parameters in the real-world situation. In the second stage, a simulation tool (Simio) was used to simulate the shop floor using the data collected in stage one. Successful execution of stage two signifies that the data collected is truly representative of the real-world conditions. In stage three, using the basics of lean methodology, various improvements were applied to the simulated model. The impact of alternative simulation models on key performance indicators (KPIs) such as throughput levels and percentage worker utilization was studied to find an optimal combination of the proposed improvements which resulted in an increment of roughly 50% in throughput levels. The results helped highlight the fact that through optimum utilization of the resources already available, productivity of an enterprise can be improved significantly.

Poster Number: 30


Data Driven Predictive Modeling of Flight Delay

Presenter: Anish Kalliguddi, Industrial, Manufacturing and Systems Engineering Graduate Student

Mentor: Dr. Aera Leboulluec

Abstract:

Flight delay has been one of the major issues in the airline industry. A study by Frankfurt-based consulting company "Aviation Experts"�, presented that costs of $25 billion were incurred in 2014 due to flight delays worldwide. Domestic flight delays have an indirect negative impact on the US economy, reducing the US gross domestic product (GDP) by $4 billion (TDI, 2010). This project investigates the significant factors responsible for flight delays. The data set extracted from Bureau of transportation statistics (BTS) containing 1,936,758 instances each having 15 attributes is used for the analysis. We describe a predictive modeling engine using machine learning techniques and statistical models to identify delays in advance, hence mitigating its effects. The data set is cleaned, imputed and a response variable is introduced in the data set to account for the overall delay. This response variable is the total time difference between the system elapsed time and the actual elapsed time. Machine learning techniques such as decision trees, random forest and multiple linear regression are used. We attempt to put forth an end-to-end solution to the delay losses incurred by the airline industry by identifying the critical parameters responsible for flight delay.

Poster Number: 31


Tribological Performance of Functionalized Nanoparticles in oils and Mechanism of Tribofilm formation under Boundary Lubrication.

Presenter: Vinay Sharma, Materials Science and Engineering Graduate Student

Mentor: Dr. Pranesh Aswath

Abstract:

Lubricants used in motor engines contain various chemical species to help enhance energy efficiency and provide increased longevity. Zinc dialkyl dithiophosphate (ZDDP) is the main antiwear additive that also doubles as an antioxidant in engine oils for light and heavy duty engines. However, a major limitation in the use of ZDDP is the creation of sludge in the oil and the deposit of volatile phosphate glass on catalytic convertors that reduce their efficiency and increase the amount of emission. There have been many studies tailored around the development of alternatives to ZDDP. In our approach, we propose the use of plasma functionalized nanoparticles, which will be used to deliver chemical species to tribological contacts to provide improved anti-friction and anti-wear benefits in boundary lubrication regime. For this work, Polytetrafluoroethylene (Teflon) nanoparticles were functionalized with Siliceous plasma coating using a rotatory plasma reactor. Oil formulation prepared using these nanoparticles was then evaluated using standard tribological test setup and its performance was compared to that of formulation containing ZDDP. The tribological data revealed significant reduction in friction and wear for oil containing functionalized PTFE. The study also involved results from surface analytical tools such as XPS and XANES, which helped to understand the mechanism of tribofilm formation. Overall, the results suggest that PTFE nanoparticles coated with Siliceous plasma films promote the formation of protective tribofilms at the interface. Therefore, this technology offers a way to develop a new class of lubricant additives which are environment friendly as well as efficient like ZDDP.

Poster Number: 32


Diesel Exhaust Gas After treatment systems: Comparative Study, Development, and Overview

Presenter: Nilay K. Srivastava, Mechanical Engineering Graduate Student

Mentor: Dr. Robert L Woods

Abstract:

Diesel engines play a significant role in the modern thriving global economy, providing a cost effective yet highly efficient means of transport by automobiles or railroad. Diesels owing to their high thermal efficiency and lower fuel consumption are also being vastly used for powering all sorts of industrial equipment including standby power generation. However, owing to the highly toxic pollutants such as unburned hydrocarbons(HC), Nitrogen oxides (NOx), Carbon Monoxide (CO) and Particulate Matter(PM), there has been a consistent urge for development in Exhaust Gas after treatment technology for diesel engines to make them fall in line with the evolving US EPA/European/Bharat Stage/Japanese emission standards. The current study focusses on the overview of various types of technologies available in the market and compares them on the specifics of performance, adaptation and application, maintenance, and cost effectiveness. Substantial progress has been made by mode of development of various systems in diesel passenger vehicles, commercial as well as industrial equipment applications. Systems such as Diesel Oxidation Catalyst, Selective Catalytic Reduction, NOx Storage Catalytic converters etc. are already being developed and used in various combinations by OEMs and integrators. Future trends in the diesel exhaust gas after treatment along with potential emerging markets have also been discussed. The comparative study also highlights the need to move towards synthetic diesel fuel with consistent heat release characteristics and to prevent discrepancies between test results in the laboratory versus the results on field.

Poster Number: 33


Skin Cancer Detection mobile app with the use of thermal imaging

Presenter: Sandeep Patil, Mechanical Engineering Graduate Student

Mentor: Dr. Brian Dennis

Group Members: Dr. Ratan Kumar, Professor of Practice, Mechanical Engineering

Abstract:

More than one million people in the United States get cancer each year. The most common type of cancer on the list is breast cancer,skin Cancer, with more than 234,000 new cases expected in the United States in 2015. On reviewing cancer, it can be noted that certain modification in DNA can cause breast cells or any cells to termed as cancerous. These changes , causes cells not to die at the right time and cancer is more likely to develop and spread. These tumors (skin, breasts) can lead to increase in local blood flow and temperature whereas vascular sclerosis decrease the blood flowing to the skin, resulting in lower skin temperature. Among various types of non-invasive techniques for tumor detection, such as ultrasound or MRI, thermal methods appear to be economic and safe. Non-invasive diagnostics can be performed from skin surface temperature measurements using inverse analysis techniques based on Pennes' bioheat equation Different methods has been tried and tested to detect cancer cells on the basis of thermal images. Earlier research has supported thermal imaging method with number of numerical study, trials and experiments. Author has developed mobil application for the same, where it has facility to capture thermal images, videos with the help of infrared imaging camera. Then this data will be stored on cloud/server and will be analysed with online framework with neural network to detect True or False about cancer. At the end, analysis will display the result as YES or NO for cancer detection. This is very quick and affordable option for one to analyse skin on daily basis.

Poster Number: 34


A Multiscale Thermostat for Fast Temperature-Controlled Molecular Dynamics

Presenter: Ashley Guy, Mechanical Engineering Graduate Student

Mentor: Dr. Alan Bowling

Group Members: Abhishek Chatterjee, Doctoral Student

Abstract:

This work investigates the application of a known multiscale method to an atomistic dynamical simulation. These simulations are notorious for requiring significant computational resources to generate even modest time evolutions. The multiscale method has been shown to greatly reduce the computation time required to simulate sub-micron continuum simulations of motor proteins, estrogen molecules, and micro-beads. The goal of this work is to adapt the known continuum formulation to the atomistic scale to similarly reduce the computation time required.

A molecular dynamics simulation was performed to test the proposed formulation. A eutectic blend of sodium and potassium nitrate ions were selected for the model. Active forces are electrostatic and Lennard-Jones potential forces. A modified Nose-Hoover thermostat is used to maintain a temperature constraint. Stochastic forces are introduced to model random thermal fluctuations.

Results show that the scaled system exhibits reduced computation time and larger usable integration time steps. Relative differences between scaled and unscaled time evolutions can be regulated through a scaling factor.

Poster Number: 35


Multibody contact and impact analysis and transition

Presenter: Abhishek Chatterjee, Mechanical Engineering Graduate Student

Mentor: Alan Bowling

Abstract:

Rigid body contact and impact analysis is one of the fundamental subfields of research in multibody system dynamics. Applications of contact and impact analyses methodology is relevant to a wide range of engineering areas such as legged robotics, earthquake engineering, game physics and virtual reality. Collisions between objects (viz. robot foot contacting ground) typically takes place over a common surface, thereby requiring multi-point contact and impact analysis. Analysis of multipoint contacts and impacts typically pose underdetermined problems, such that there exists more number of unknowns (contact forces) than equations.

This work proposes a method for resolving this underdetermined problem, by deriving additional constraint equations based on the properties of rigidity. Energetic constraints are also used in this work to ensure energy consistency during impacts. Lastly, this work proposes a transition scheme for switching between contact and impact states for rigid body systems.

Poster Number: 36


Numerical Study on Morphology and Solidification Characteristics of Successive Droplet Depositions on a Substrate

Presenter: Vimalan Adaikalanathan, Mechanical Engineering Graduate Student

Mentor: Dr. Albert Tong

Abstract:

Successive droplet impingement finds extensive applications in additive manufacturing technologies. Detailed knowledge about the flow behaviour, phase transformation and free surface deformation is required to have a complete understanding and optimization of the process parameters. Experimental research in this field is limited due to extremely small length and time scales involved. Numerical solution of governing equations involves challenges such as tracking multiple deforming interfaces, highly non-linear flow field, surface tension, contact resistance and modeling successive droplet impacts. The present study employs a non-isothermal phase change approach with an enhanced interface tracking scheme to accurately model impact dynamics, surfaces deformation and phase change. Effects of impact conditions on single as well as successive droplet depositions have been examined. The role of convection in the energy equation has been emphasized and quantitatively analyzed.

Poster Number: 37


Analytical Study of Light Scattering by Small Particles for High-Speed Flow Visualization

Presenter: Alexandra Kessler, Aerospace Engineering Undergraduate Student

Mentor: Frank Lu

Abstract:

The PIV (Particle Image Velocimetry) technique is versatile and has proven to be a popular method for obtaining particle velocities in a liquid flow. A serious challenge lies in the seeding of the flow by nanoparticles. For supersonic flows, the particle of choice has been titanium dioxide in the submicron range. However, titanium dioxide's density is high. Thus, these particles may not properly follow the fluid particles. This causes uncertainty in resolving shock locations due to the longer relaxation time. A proposal was made to examine other nanoparticles that exact a smaller relaxation time.

In order to eliminate unsuitable particles, a criterion for particle selection was developed. Each particle for consideration was researched through texts, catalogued, and compared using properties that included its relaxation time, density, commercially available and purchasable diameters, morphology, index of refraction, flammability, emissivity, softening temperature, and the toxicity of the material to human contact. Finally, diamond nanoparticles were compared to Titanium Dioxide with regards to size and intensity of refraction through computations in MATLAB and MIEPLOT.

Through this research, it was concluded that spherical Nano diamonds are ideal for PIV experiments. However, the cost of these nanoparticles exceeds available funding for now. Therefore, the particle used at the ARC should remain Titanium Dioxide. In the meantime, purchasing Titanium Dioxide with spherical morphology may be worth the effort due to an improvement in tracking and flow purposes. This new information will improve the accuracy of PIV systems in the future in the field of mechanical engineering.

Poster Number: 38


Development of High Frequency Solenoid Valve Operation for Detonation Engine

Presenter: Gilberto Olvera, Aerospace Engineering Undergraduate Student

Mentor: Dr. Abdul Raheem Bello

Abstract:

Pulse detonation engines have the potential to be more efficient than conventional deflagration engines. However, there are many challenges that must first be overcome. One such challenge is the need to inject fuel at a fast enough rate to be used in practical propulsion systems. Although there are various concepts for detonation engines, the pulse concept utilizes solenoid valves to feed fuel and oxidizer to the engine. A limiting factor for this concept is that a solenoid valve experiences mechanical delays due to the inertial forces of its moving parts. The purpose of this experiment was to overcome this obstacle and operate a solenoid valve at frequencies beyond its original limit. Through the creation of various virtual instruments in LabVIEW, and an Agilent high voltage power source, a strategic custom voltage waveform was created. The waveform exploited the electromagnetic coil within the solenoid valve such that it was possible for the valve to cycle between open and closed positions at a higher speed. The voltage profile allowed the solenoid valve used to exceed its original operational frequency range tenfold. The frequencies achieved met the criteria of 50-100 Hz frequency range stated in literature for competitive operation for pulse detonation engines as propulsion systems.

Poster Number: 39


Novel STAT3 Inhibitor Loaded Dipalmitoylphosphatidylcholine-Poly(lactic-co-glycolic acid) (DPPC-PLGA) Nanoparticles For Treatment of Lung Cancer

Presenter: Matthew Muir, Bioengineering Undergraduate Student

Mentor: Dr. Kytai Nguyen

Group Members: Daria Zhukova, Roshni Iyer, Gizem Oter

Abstract:

The American Lung Association found that, in the year 2016, 158,000 deaths were attributable to lung cancer, and accounted for 27 percent of all cancer-related deaths that year. While prognostication of the disease is improving, current treatment modalities, including chemotherapy, target both cancerous and healthy cells, leading to non-specific treatment and severe side effects to other healthy organs. Thus, it has become necessary to develop more precise drug delivery systems to effectively treat this deadly disease. Dipalmitoylphosphatidylcholine (DPPC) is one of the major constituents of the lung surfactant. We have taken advantage of DPPC molecule to develop smart DPPC-PLGA hybrid NPs for chemotherapeutic drug delivery to the lung. The DPPC molecule was hypothesized to enhance the homing of the nanoparticle in the lung and provide a more controlled release of the chemotherapeutic agents. These nanoparticles were then loaded with the cryptotanshinone and nifuroxazide, two currently FDA approved drugs again STAT3 gene, which has been shown to be overexpressed and upregulated in pulmonary adenocarcinoma. The DPPC-PLGA NPs were generated using a single emulsion technique. They were found to have an average diameter of 212 Â± 81 nm. Cytotoxicity studies showed DPPC-PLGA NPs to be cytocompatible up to 1000 ug/mL. Release kinetics of cryptotanshinone and nifuroxazide were bi-phasic with a burst release of 40% within a day and a sustained release over a month. These NPs were demonstrated to be hemo-compatible with hemolysis of less than 3% and the blood clotting trend following that of the saline control. The DPPC-PLGA NPs were evaluated in vitro and shown to be cyto and hemo-compatible. They also displayed a controlled release of the two selected chemotherapeutic drugs. Upcoming studies will include in vitro and in vivo evaluation studies of these NPs to assess their therapeutic efficacies for lung cancer treatments and subsequent downregulation of STAT3 expression in lung cancer cell lines.

Poster Number: 40


Hyaluronate-Dopamine Mussel Inspired Hydrogel

Presenter: Valinda Jones, Bioengineering Undergraduate Student

Mentor: Kytai Nguyen

Abstract:

Bioadhesives are synthetic or natural polymers that are used for adhering biological tissues finding applications in surgery and soft tissue engineering. Currently many clinically applied bioadhesives do not possess strong wet tissue adhesion and are not readily resorbable. Better alternatives to address this limitation involve using chemical inspirations from marine organisms like mussels which can stick to surfaces under water. Here we tried a combination of mussel-inspired hydrogels and nanoparticles to function as wet tissue adhesives properties.

A mussel inspired polymer (MIP) was synthesized by grafting dopamine onto sodium hyaluronate (HA) using aqueous EDC-NHS carbodiimide chemistry. We formulated several nanocomposites by combining MIP with poly (D,L-lactic-co-glycolic acid) (PLGA) nanoparticles (NPs), or N-hydroxysuccinimide (NHS) modified PLGA NPs (PLGA-NHS) using sodium metaperiodate as a cross-linker. We characterized the wet tissue adhesiveness of the nanocomposites on porcine skin-muscle samples using uniaxial lap shear tests using a MTS insight workstation. The effect of nanoparticle concentration (0-50%w/v) on the wet tissue adhesion was also studied.

The HA-Dopa had a dopamine content of 32.7 Â± 1.3%. Mechanical testing data shows that the inclusion of nanoparticles in HA-Dopa hydrogels enhanced the wet tissue adhesion up to a maximum lap shear strength value of 38.21 Â± 2.16 kPa in the MIN-PLGA-NHS group, compared to HA-Dopa alone (20.06 Â± 2.8 kPa). The variation of nanoparticle concentrations revealed a concentration-dependent increase in adhesive strength in all groups of MINs.

The preliminary results of this research indicate that these wet tissue adhering nanocomposite materials can serve as promising replacements of current clinically used bioadhesives.Our future work will focus on characterizing the biocompatibility and therapeutic efficacy of these nanocomposites in vitro and in vivo using cell cultures and animal models.

Poster Number: 41


The Use of Modified Moisture Barrier to Mitigate Edge Cracking in Flexible Pavement in North Texas

Presenter: Kelli Greenwood, Civil Engineering Undergraduate Student

Mentor: Dr. Sahadat Hossain

Group Members: Aya Shishani, Asif Ahmed

Abstract:

In addition to causing shrinkage and swelling in expansive subgrade, variation in moisture alters the material properties of soil, which ultimately affect pavement performance. The appearance of longitudinal cracks near the edge of pavement as a result of seasonal moisture variation is common in North Texas. In order to combat this intrusion of moisture near the edge of pavement, both horizontal and vertical moisture barriers have been used with limited success. The current study utilizes a modified and new moisture barrier (a combination geomembrane and geocomposite) to control moisture intrusion into the subgrade soil. The current study monitors variation of subgrade moisture content, rainfall, and pavement deformation of a section of Farm-to-Market (FM) 987 near Kaufman, Texas. A previous study near the area produced significant moisture variation with evident correlation with rainfall and concluded that pavement deformation varied with rainfall. The current study includes two sections, a section with the modified moisture barrier and a control section without the barrier. The continuous monitoring program includes moisture content and deflection measurements in both sections. The section with the moisture barrier is expected to exhibit lower moisture variation and less pavement deformation than the control section.

Poster Number: 42


Monitoring the In-Situ Hydraulic Conductivity of Landfill Final Cover

Presenter: Lucas Hoyos, Civil Engineering Undergraduate Student

Mentor: MD Sahadat Hossain

Group Members: Md. Jobair Bin Alam

Abstract:

Monitoring the percolation and hydraulic conductivity of the soil on ET cover systems is paramount in the proper maintenance of the landfill cover. However, some of the methods used for the supervision of these properties of the soil are highly destructive, which directly affects the performance of the cover when using an innovative technique as an evapotranspiration cover. As a solution, the permeability of the soil is monitored using the Guelph Permeameter. An instrument that provides accurate and fast results with a very limited impact of the integrity of the cover. Based on the results provided by the instrument an evaluation of soil hydraulic conductivity, soil sorptivity, and matrix flux potential can be made in all types of soils. Further proving the versatility of this technique that is currently being used on both locations being monitored; Irving Landfill, and Denton Landfill. The expected permeability of the soil for an ET cover system in theory should range from 1.00E-07 cm/s to 1.00E-09 cm/s. Both sites have been under monthly monitoring for the past 9 months, and the highest registered value is 8.58E-07 cm/s which is still within the acceptable limits for permeability. The objective of this study, however, is to relate the changes in the permeability of the soil to the seasonal changes of weather to ultimately develop a pattern that can be used as a reference in further studies.

Poster Number: 43


MyoLearn - Using Myo Armband for Vocational Assessment

Presenter: Dylan Ebert, Computer Science Engineering Undergraduate Student

Mentor: Fillia Makedon

Abstract:

This project looks at using the Myo armband and machine learning techniques to detect irregularities when performing a vocational assembly task. A Lego car assembly task is performed while Myo data is collected, which includes accelerometer, gyroscope, magnetometer, and EMG. Principal Component Analysis is then used to reduce dimensionality and discover if long-term deviations from the assembly task can be detected, indicating a potential health and safety risk and need for assessment.

Poster Number: 44


360 OmniAwareness

Presenter: Armaan Zirakchi, Computer Science Engineering Undergraduate Student

Mentor: Hakki Erhan Sevil

Group Members: Cody Lundberg

Abstract:

Computer vision is commonly used to detect and track motion using a conventional camera, but that limits the field of view (FOV). This study is to attempt to overcome this challenge by using a 360 camera. In this research, our approach utilizes the background subtracter from OpenCV Library which creates a continuously updating background model for the motion detection. The model is subtracted from the current frame leaving contours that symbolize the movement observed in the camera's view. These contours are then analyzed and processed so that the system can track the largest contour. The tracked movement is outlined and directed to the user via Virtual Reality (VR) headset. The VR headset only displays a portion of the 60 camera view to the user which provides more realistic situational awareness of the surroundings while the system still searches the rest of the camera view.

Poster Number: 45


An Experimentally Validated Method for Temperature Prediction During Cyclic Operation of a Li-ion Cell

Presenter: Divya Chalise, Mechanical Engineering Undergraduate Student

Mentor: Dr. Ankur Jain

Group Members: Krishna Shah, Lidiya Komsiyska, and Tobias Halama

Abstract:

Heat generation during the operation of a Li-ion cell results in large temperature rise, particularly at high discharge rates. Accurate prediction of temperature rise during operation is a key technical challenge that directly affects both performance and safety. Li-ion cells are often used in cyclic charge/discharge manner, making this a particularly important process to study. This research presents an experimentally-validated analytical method to rapidly and accurately predict the temperature field in a Li-ion cell undergoing cyclic charge and discharge. The method, based on recursive solution of the governing energy equation in each period of the cyclic process, is shown to result in very good agreement with experimental data for over fifty cycles of high-rate cycling of cylindrical 18650 Li-ion cells with the maximum disagreement of only 5.7%. Results indicate that heat loss through the metal foil that provides electrical interconnection is a critical process that governs overall thermal behavior of the cell. A novel technique based on determining the effective heat transfer coefficient of the interconnection is studied and described, and it is shown that accounting for this effect results in very good agreement with experimental data. Results from this research may be helpful for design of Li-ion cell systems, as well as real-time temperature prediction and performance optimization.

Poster Number: 46


Characterization of Early Damage in Airframe Structures using Embedded Magnetostrictive Particles

Presenter: Nicolas Long, Mechanical Engineering Undergraduate Student

Mentor: Joan Reinhardt

Abstract:

Early stage material damage in critical airframe structures is not detectable with existing sensing techniques such the ultrasonic pitch-catch or pulse-echo. These methods are only reliably for detection of macroscopic damage, such as large cracks or delamination and as such by the time macroscopic damage is detected most of the structural life might have been expended resulting in a high risk platform operation and/or unplanned downtime. Here in, an experimental study was conducted to investigate the viability of embedded magnetostrictive particles for detection of early stage structural damage in composite materials. Test specimens were fabricated from thirteen unidirectional plies of pre-preg carbon/epoxy material system with Terfenol-D particles evenly spread in mid layer. The specimen were then subjected to cyclic fatigue loading while monitoring the change in the magnetic flux density using an induction coil. Acoustic emissions were captured simultaneously using two wide-band sensors mounted within the gage length of the specimen. Preliminary test results show that the embedded system exhibits a change in magnetic flux strength starting from the first few fatigue load cycles.

Poster Number: 47


Measuring of Thermal Properties of Lithium Ion Batteries

Presenter: Bilal Ahmed, Mechanical Engineering Undergraduate Student

Mentor: Ankur Jain

Group Members: Salwa Shaik

Abstract:

Lithium ion batteries, besides revolutionizing the portable electronics industry, have turned the dream of electric cars into reality today. Their high energy density is their most significant advantage over other conventional battery technologies. While lithium ion batteries have gained so much popularity over the years, their tendency to catch fire under stressful conditions has raised safety issues and has limited their use. Hence, there is a strong need to address the thermal dissipation issues associated with Li-ion batteries. To better understand the heat dissipation phenomenon of the battery, it is imperative to know its precise thermal properties. Therefore, this research study is based on determining the thermal conductivity and specific heat capacity of the Li-ion batteries. A mathematical model is developed that predicts the temperature change as a function of time of the battery when subject to an inflow of heat flux. Specific heat capacity and thermal conductivity are the two parameters of the model. The model and the experimental setup are first validated by conducting experiments on materials with well-known thermal properties. Once validated, the setup will be used to predict the thermal conductivity and specific heat capacity of the Li-ion battery. A mathematical approach based on D-optimality is employed to determine the sensitivity of the model and experimental setup to each of the two parameters (thermal conductivity and specific heat capacity) involved. This helps in providing confidence in the accuracy of the results of this study. The results of this study will help better understand the thermal behavior of Li-ion batteries.

Poster Number: 59


The Forgotten Dimension: National Investigation of the Relationship between Urban Form and Regional Innovative Capacity

Presenter: Ahoura Zandiatashbar, Urban Planning and Public Policy Graduate Student

Mentor: Shima Hamidi

Group Members: Shima Hamidi

Abstract:

In the era of knowledge economy, knowledge is seen to be the driver of economic growth. Although the role of built environment and knowledge production has been well studied, there is little evidence on how urban form influences regional innovative capacity. To address this gap, this study examines the relation between urban sprawl and regional innovative capacity. Accounting for confounding factors, we found that for every percentage increase in the metropolitan compactness index, the percentage of patent generated per capita increases by 0.38 and the percentage of small business' innovations increases by 0.47, while there is a positive correlation between metroplitan compactness index and number of innovative firms. The lack of opportunities for knowledge spillover and spatial proximity of economic drivers in the sprawling areas could be possible explanations. Moreover, the knowledgeable millennials generally do not prefer to live in sprawling areas.

Keywords: innovative capacity, accessibility, built environment, urban sprawl, compactness

Poster Number: 60


The Outside World Is Scary and Dangerous: A Content Analysis of Xinwen Lianboâ€™s News Coverages on Foreign Affairs

Presenter: Zedan Xu, Communication Graduate Student

Mentor: Dr. Andrew Clark

Abstract:

This study examined how China's most watched daily news program covered foreign affairs through the lenses of Agenda Setting Theory. A daily news program produced by China Central Television (CCTV), Xinwen Lianbo (translated to News Simulcast) has dominated prime time television for tens of millions of Chinese families since first aired in 1978. As the most well- known and influential mouthpiece news program in China, it is simulcast by all the central, provincial and civic television stations at 8 P.M. (UTC Time). Prior research has indicated that Xinwen Lianbo has been serving more as a means for the Chinese government to divulge its political agenda rather than to examine the day's important news events. However, the way of how this daily news program covered and framed foreign affairs remained unanswered. To examine the agenda-setting impact of Xinwen Lianbo, this study conducted a quantitative content analysis of its news coverages on foreign affairs from 2011 to 2016. The research results suggested that Xinwen Lianbo's coverages on foreign affairs were highly crisis-related: Foreign countries were always reportedly associated with terrorist attacks, armed conflicts, natural

disasters, refugee crisis, nuclear crisis etc. Very few news coverages on foreign affairs were reported positively or neutrally. In conclusion, Xinwen Lianbo did not tell people "what to think", but it did tell its audience "what to think about". By negatively framing the news coverages on foreign affairs, the news program successfully set the agenda and presented to the audience that the world outside China is scary and dangerous.

Poster Number: 61


Lacanian Subjects Made Strange: Animal Agency in Uncanny Places and Questionable Proximity

Presenter: Samuel Fatzinger, English Graduate Student

Mentor: Neill Matheson

Abstract:

For animals such as Kafka's Red Peter, subjectivity exists between boundaries that separate humans from non-human animals. These boundaries are erected through theoretical propositions of language use and the transition from the Lacanian Real into the Symbolic order. Red Peter, feral "wolf-children,"� and Poe's Ourang-Outang from "The Murders in the Rue Morgue,"� serve as examples in which beings exist in the liminal space between the human and non-human animal. I argue that language and the Lacanian concept of the Law of the Father, Freud's concepts of the uncanny and the unheimlich, and the cultural practice of naming, all push for a posthuman view of being and subjectivity that calls into question the legitimacy of boundaries that historically have served to separate humans and non-human animals while ignoring beings that cannot be categorized through such limitations. Such an examination brings to light liminal beings and simultaneously challenges Cartesian animal normativity while attempting to provide a sense of subjectivity that is ignored under Cartesian thought.

Poster Number: 62


Assistive Technologies, Tutoring, and the Online Writing Lab (OWL): Access and Equity in Writing Supplementation for Students with Disabilities

Presenter: Angela D. Mack, English Graduate Student

Mentor: Dr. Estee Beck

Abstract:

Assistive technologies provide one of the best adaptive measures for students with disabilities who seek tutoring in college writing centers through the medium of online writing labs (OWLs). The technologies, consisting of specialized computer software/hardware, equipment, or online tools, enable students to have greater control and access to supplemental resources that they may otherwise deem restricted or prohibited. Often, the issue surrounding assistive technologies involves concerns of maintenance and upkeep or staff training needed to facilitate its use. This can seem more apparent when managing the online writing/tutoring space. However, the greater issue is not the mechanism of the technologies themselves because many students with disabilities already use such programs in other areas of their lives. I argue that assistive technologies in OWLs promote best practices towards disability inclusion; foster blended learning in the online environment; and mediates student empowerment through offering tutoring that disabled students can connect with asynchronously and use beyond the physical constraints of a writing center facility. Therefore, more writing centers should mandate their OWLs to become more disability compliant or implement an OWL if one has not already been established with the disabled student in mind. With assistive technologies in OWLs, writing supplementation becomes more widely available, thus promoting and reinforcing tutoring as a critical resource in overall student success.

Poster Number: 63


Mapping Indian Country: Culture Areas, Linguistic Stocks, and the Genealogy of a Map

Presenter: Robert Caldwell, History Graduate Student

Mentor: Dr. Imre J. Demhardt

Abstract:

Throughout the 19th and 20th centuries, anthropologists employed social-scientific thematic maps to help sharpen their understanding of the indigenous cultures of the Americas and to explain the American Indian past to the broad populace. While anthropologists initially depended on insider knowledge of a range of American Indian informants to create continental-wide maps, their works generalized and schematized American Indian cultures. The maps also conveyed the cultural biases of their European or Euro-American creators. Over time, the map depictions are understood as established “facts” rather than “research leads” or pedagogical devices. These maps continue to be utilized by historians, anthropologists, cultural and regional geographers, and in the field of Native American and Indigenous studies. But the maps are often employed in an uncritical manner. My poster presentation traces the evolution of these ethnographic, archaeological, and linguistic maps, noting their many uses throughout time and their continuing usefulness today. It also offers important caveats regarding their limitations for present-day scholarly application.

The maps offer one important window onto the roots and routes of scholarly (scientific and social-scientific) knowledge regarding American Indians. Study of the intellectual trends that led to the creation of the maps is one important aspect of such a study. In doing so, the research provides a useful history of social science while challenging long-held assumptions.

Poster Number: 64


Production and Perception of English Stops by Arabic Speakers

Presenter: Abdulrahman Dallak, Linguistics Graduate Student

Mentor: Cynthia Kilpatrick

Abstract:

This study aims to investigate how Arabic speakers learning English as L2 learn to produce and

perceive acoustic properties of English stops. That is, it generally tests whether prevoicing, as

reported by Flege & Port (1981), is a fundamental acoustic cue for voicing contrast to Arabic

speakers learning English. In addition, if this claim is sound, how does prevoicing affect the

production and perception of English stops produced by Arabic speakers? Two experiments were

conducted (i) production experiment, and (ii) perception experiment. Participants were divided

into three groups based on language proficiency (i) 7 native English speakers, (ii) 7 proficient

Arabic speakers, and (iii) 7 less-proficient Arabic speakers. The first experiment shows that native

English speakers produced all stop sounds with positive VOT values, whereas both Arabic groups

produced all voiced stops with negative VOT values, except that the proficient group produced /g/

sound with positive VOT values, similar to that of native speakers. In addition, production

experiment shows that Arabic speakers produced all voiceless stops with VOT values smaller than

that of native speakers; however, that the less proficient group produced /p/ sound with

significantly shorter VOT values (23 ms). As for perception experiment, it shows that listeners had

difficulty identifying /p/; it often interpreted as [b] because of the smaller VOT values. In addition,

this study confirms that prevoicing is a primary acoustic cue for voicing contrast in Arabic

speakers' tokens.

Poster Number: 65


Independent of L1: Accessing L2 meaning in early and late Vietnamese-English bilinguals

Presenter: Juliet Huynh, Linguistics Graduate Student

Mentor: Naoko Witzel

Abstract:

Various studies have set out to uncover how meaning from the second language (L2) is activated, but have not reached a consensus. The purpose of this study was to investigate whether (i) highly-proficient early and late Vietnamese-English bilinguals who were Vietnamese-Americans from the Dallas-Fort Worth area activate L2 meaning from L2 words, (ii) this access to L2 meaning relies on assistance from L1 mediation, and (iii) this activation in L2 meaning depends on the age of exposure to the L2. Early and late Vietnamese-English bilingual participants studied lists of L2 words that were associated to one another (i.e. bed, rest, dream, and awake) by a topic word, or critical lure, (sleep) in hopes that the two bilingual groups would activate the meaning of the words in the list as well as the critical lure. If they activated meanings of L2 words on these lists, then they will show facilitation in recognizing the words on the list when the words were preceded by a related L2 (in Experiment 1 and 3) or L1 (in Experiment 2) critical lure in the test session. Early bilinguals showed facilitation from both L2 (Experiment 1) and L1 Vietnamese (Experiment 2) primes, while late bilinguals did not. Once the target presentation was delayed, late bilinguals showed facilitation from L2 primes (Experiment 3). We argue that the differences between the early and late bilinguals can be explained through the difference in the richness of associative networks for each bilingual group.

Poster Number: 66


Listener perception of speakers of English

Presenter: Shannon Belden, Linguistics Graduate Student


Group Members: Laurel Whitsett

Abstract:

Received Pronunciation (RP), a manifestation of Southern British English (SBE), is a common model accent indicative of upper-middle and upper classes in Britain. It is commonly used in films and plays and, along with Standard American English, is the most commonly used accent in teaching English as a foreign language (Giegerich 1992: 44). In this project, we considered perceived and produced differences between native speakers of RP and American actors performing with RP dialects, focusing specifically on areas of rhoticism (pronunciation of [r]) and vowel shaping.

Results of a perception-based listening experiment using extracts from films with both native and non-native speakers of RP indicated that listeners are more likely to make perceptual choices about speakers of English based on rhoticity than on vowel pronunciation. We also found that listeners were more likely to rate a speaker as a native RP speaker based on vowel pronunciation that was not traditionally American. These results are useful from a linguistic perspective, where they reveal information about the divergence between RP and Standard American pronunciations; a TESOL perspective, where they can aid in understanding what may be a product of training in another dialect of English and what may be a true error that needs to be addressed; and an acting perspective, where they can help those rehearsing an RP accent to understand some of the differences between RP and Standard American English.

Poster Number: 67


A corpus-based analysis of adjective disparity in the 2016 election

Presenter: Darcey Browning, Linguistics Graduate Student

Mentor: Laurel Stvan

Group Members: Kristen Fleckenstein

Abstract:

Overview: In the professional realm, men and women are not granted the same identities. There is a double standard where men’s ambition is rewarded, but women are viewed negatively for similar traits (Okimoto & Brescoll 2010). Adjectives like shrill, abrasive, and nasty are rarely leveled at men the way they are at women. The 2016 presidential election cycle featured linguistic choices that illustrate how society innately values men and women in different ways.

Corpora Collection: We gathered two corpora: editorials and opinion pieces from 13 major media outlets and over 55,000 tweets with #NastyWoman.

Degree Adverbs: Criticism of Hillary Clinton focused on aspects of her personality and identity that did not follow traditional gender roles, emphasizing her ambition and perceived coldness. These critiques were frequently embedded in "too x" and "not x enough" constructions, shown in (1):

Too controlled and rehearsed as a candidate.

These same structures were less frequently used to describe Donald Trump;reporters focused on aspects of his personality that related to his presidential abilities, as in (2):

(2) He is too lazy, ignorant, [...] to do the job.

Reclaiming Nasty: After Trump described Clinton as a nasty woman, tweeters continued this term via the #NastyWoman hashtag, highlighting the adjective disparity . While #NastyWoman was sometimes used pejoratively, examples of reclaimed #NastyWoman appear in (3) and (4):

(3) This #NastyWoman just voted [...]

(4) This daughter of a #badhombre and a #nastywoman just cast her ballot [...]

With reclamation, supporters “rebel against the speech of hate” (Brontsema 2004:16). These reclaimed versions of nasty serve as a rejection of the cultural values imposed on Clinton, and allow tweeters to claim their own agency in their identifying terminology.

Conclusion: We show that the use of adjectives in the 2016 presidential election reveals an underlying ideology shaping women's identities in male-dominated spheres.

Poster Number: 68


A look into Korean stress: A perception and production study

Presenter: Kevin Daily, Linguistics Graduate Student

Mentor: Dr. Cynthia Kilpatrick

Abstract:

The location and even the very existence of Korean stress is still debated. Most agree that stress is found either on the first or second syllable of a word regardless of syllable length (Ko 2013; Lee 1990; Jun 1998). Ko (2013) argues that most analysis of stress placement comes from the author's intuition. Because of this, the present study sought to do a phonetic analysis of stress on Korean verbs and present acoustic evidence for stress location. We focused on base verbs of two and three syllables that had past tense and polite style suffixes to create three and four syllable words. We sought to find if the stress position from the base word stayed in the same position when more syllables were added.

In this paper, we discuss the location of stress based on the pitch and intensity in the target words. We also show a comparison of these locations to the intuitions of the participants in experiment 1. This will serve to indicate the accuracy of native speaker's intuitions of the placement of stress in a word. This is important for future perception research on stress in Korean as it has been argued that Korean speakers can be good at identifying vowel length but not necessarily stress location.

Poster Number: 69


Acoustic Analysis of /s/ Palatalization in English Loanwords in Korean

Presenter: Seula Han, Linguistics Graduate Student


Abstract:

Loanword phonology has been extensively researched cross-linguistically since the late 1980s, as it relates to phonetics and perception in phonology. When a language adopts words from another language, it tries to adopt them as close to their original forms as possible while trying to bring the words into conformity with its phonology at the same time (Silverman 1992). Research on English loanword phonology in Korean has reported on various types of phonological modification. However, there have been very few studies that closely examined the adaptation of the palatal /Êƒ/ in English words borrowed into Korean. The primary goal of this study is to examine the process of /s/ palatalization in word-initial position in English loanwords adopted into Korean using experimental data.

The research questions investigated are: (1) How does Korean adopt English loanwords with the palatal /Êƒ/ in word-initial position when it is not followed by a high front vowel? (2) After the modification, how similar is the modified /s/ to the English palatal /Êƒ/?

The participants were native speakers of Korean who are proficient in English. In a sound-proof booth, they were asked to produce English loanwords adopted into Korean while their production was being recorded. The stimuli consisted of English-based loanwords with /s/ followed by a high front vowel, English-based loanwords with /s/ followed by a glide, and Korean words with /s/ followed by a high front vowel. The recordings were analyzed acoustically using the software Praat, focusing on spectral center of gravity (CoG) to examine the varying degrees of palatalization.

The results reveal some interesting characteristics of /s/ palatalization in English loanwords adopted into Korean. The presentation will discuss the differences in acoustic features of /s/ in various environments. The impact of the study and possible future directions will also be discussed.

Poster Number: 70


Wondering if subjects can be omitted in English? Evidence from COCA

Presenter: Carly J. Sommerlot, Linguistics Graduate Student

Mentor: Dr. Joseph Sabbagh

Abstract:

Subjects in English can be omitted (i.e. not pronounced) in a variety of contexts, with a variety of different subjects:

(1) Remember Tyke? (He) Lived next door to Mom? [SBCSAE]

(2) (It) Looks like rain. (Quirk et al 1985: 896)

One current syntactic approach to such constructions requires that subjects can only be omitted i) in certain registers, namely written registers, and ii) when they occur at the left edge of a clause (Haegeman 2013). This approach predicts that omission will be impossible if there is any syntactic material to the left of the omitted subject. However, a review of corpus data reveals that this appears to be incorrect, as there are a number of examples where subject omission occurs with a wh-phrase to the left of the omitted subject:

(3) How (can we) explain its worship in New York and nationwide? [COCA 2001: American Spectator]

Data like (3) dismantle Haegeman's approach, which crucially relies on subjects being located at the left edge; this current approach, then, is incapable of accounting for all the data. Furthermore, constructions with omitted subjects occur in a variety of registers beyond the written: spoken, fiction, news, and more. This suggests that this phenomenon is more widespread than previously discussed. Data like (3) will be presented in detail, along with additional evidence from subject-auxiliary inversion and quantifier scope. The evidence presented in this poster suggests the need for a revision to Haegemanâ€™s account of subject omission.

Poster Number: 71


Processing L2 Scripts in Highly-Proficient Bilinguals

Presenter: Ehsan Shafiee Zargar, Linguistics Graduate Student

Mentor: Naoko Witzel

Abstract:

This study investigates the difficulties of processing L2 words at the orthographic processing stage in different-script bilinguals. Different models of bilingual lexicon have attributed the shortcomings of processing L2 words to later stages of lexical processing, such as activation of the mental representations of L2 words (Dijkstra & van Heuven, 2002) or accessing these words' meanings (Kroll & Stewart, 1994; Finkbeiner, Forster, Nicol & Nakamura; 2004). However, the possibility that the difficulties of L2 lexical processing in different-script bilinguals may start earlier, i.e., at the orthographic processing stage, has not been investigated. In the current study, a group of native English speakers and a group of highly proficient Persian-English bilinguals were tested in a masked priming lexical decision experiment with repetition (beard-BEARD), anagram (bread-BEARD) and control primes. While the native speakers' responses were facilitated only by the repetition primes, the Persian-English speakers yielded facilitatory priming effects from both repetition and anagram primes. These results suggest that the Persian-English bilinguals were unable to distinguish between orthographically similar English words at a very early stage of processing. Based on these results, it is concluded that even at higher levels of proficiency, different-script bilinguals' L2 orthographic processing is not as accurate as native speakers. In other words, the difficulties of L2 lexical processing in these bilinguals start earlier than what the current models of bilingual lexicon have suggested.

Dijkstra, T., & Van Heuven, W. J. (2002). The architecture of the bilingual word recognition system: From identification to decision. Bilingualism: Language and Cognition, 5(03), 175-197.

Finkbeiner, M., Forster, K., Nicol, J., & Nakamura, K. (2004). The role of polysemy in masked semantic and translation priming. Journal of Memory and Language, 51(1), 1-22.

Kroll, J. F., & Stewart, E. (1994). Category interference in translation and picture naming: Evidence for asymmetric connections between bilingual memory representations. Journal of memory and language, 33(2), 149-174.

Poster Number: 72


How U.S. Companies Secure Their Interests in the Middle East: Corporate Influence in Foreign Policy

Presenter: DeAnne Hurtado, Political Science Graduate Student

Mentor: Dr. Herschel Thomas

Abstract:

Recent studies of corporate lobbying utilize longitudinal data to understand how U.S. businesses seek to influence government decision-making (Drutman 2015). This paper extends this line of research by focusing on U.S. companies who engage in foreign policy lobbying to protect and maintain their interests in the Middle East. Due to the recent and continuous wave of revolutionary change in the region, U.S. foreign policy can affect who wins and who loses among business interests. Through content analysis of lobbying disclosure reports, this paper examines U.S. corporate lobby ing related to fifteen countries within the Middle East (e.g. Turkey, Iran, Israel, Saudi Arabia, United Arab Emirates) from 2008-2016. I explain how much these organizations lobby as a function of threats of instability in the Middle East, their assets in particular countries, and government attention to foreign policy.

Poster Number: 73


The Effect of the Feminist Movement on Women's Political Involvement in the United States

Presenter: Natalie Thomas, Political Science Graduate Student

Mentor: Dr. Susan Hekman

Abstract:

As of 2016, the United States of America ranks 99th in the world --out of 193-- for women in legislature despite a long history of women's rights movements. I compared the timeline of the feminist movement in the U.S. to the history of women's political gains to determine what effect, if any, the women's rights movement had on political engagement. With the chronology compared, it is easy to see if there were any specific points in the feminist movement that motivated women to become more politically active. Women's political involvement increased after the 19th amendment was ratified, following World War II, and during the Sexual Revolution of the late 1960s and early 1970s. However, only 20% of Congress is female, and a lack of young women entering the political arena now gives little hope that women's political involvement will drastically increase soon.

Poster Number: 74


THE ROLE OF INTEREST GROUPS IN AIRLINE REGULATION (1978 â€“ 1985)

Presenter: Richard Irwin, Political Science Graduate Student

Mentor: Herschel Thomas

Abstract:

Research on interest groups is about understanding the role that organized interests play in the political process. Conventional wisdom is that powerful business interests can spend a large amount of money lobbying to prevent regulation. I argue whether interest representation is biased towards business organizations, the policy process involves many different actors and the participation of interest groups play an important role. I will examine literature on regulation policy making in the airline industry tracing important players in regulation policy over time. Using a policy history approach for a case study on interest groups will enumerate the many ways in which influence translates into power when regulating the airline industry. I will then consider whether organized business interests were disproportionately represented in airline regulation policy from 1978 - 1985.

Poster Number: 75


The Emotional Healing Behind Words: The Emotional, Psychological, and Spiritual Healing in Writing Poetry

Presenter: Esther Kentish, English Undergraduate Student

Mentor: Kenton Rambsy

Abstract:

At age 6, I had to make my homeless mother a peanut butter and jelly sandwich with inexperienced hands. At age 8, I used those same hands to help with her burial. At age 15, I had to protect myself from emotional and domestic abuse. These experiences are the basis for major themes in my writing within my recent publication, "The Emotional Healing Behind Words." Poetry is a living, literary organism designed as a structural catalyst for human beings to be expressive. Poetry allows individuals to reflect on difficult facets of life in order to reveal pertinent information about themselves and the world around them. This research presents a poetic corpus and critical metadata analyses organized to examine emotional, psychological, and spiritual development over time.The specific linguistic feature which contribute to the structure of my poems and others provides the basis for my research. In this project, I use Voyant Tools to perform a cross- textual written and metadata analyses of a collection of self-authored poems that appear in The Emotional Healing of Words poetry anthology. First, I extract numerical data in my poems related to frequently used words and lexical densities to identify notable trends in my writing. Second, I utilized the text analyses to define quantitative and statistical correlations between the thematic and literary content and actual words. The examination of particular poems through the means of text-mining and a close reading conduction to explore both literary and quantitative elements of the corpus at large. Third, I studied literary and quantitative elements that are examined in the book are grammatical nuances, raw frequency, lexical complicity, and word density. As a result, the quantitative binary between the actual words and the numerical findings produce findings that help the human race reach a closer understanding of God, the world around them, and their innate selves.

Poster Number: 76


Distrust of the Biomedical System and the Steps Immigrants take to Reconcile Their Care

Presenter: Noemi Rodriguez, Sociology and Anthropology Undergraduate Student

Mentor: Dr. Isabel Montemayor

Group Members: Cynthia Reyes

Abstract:

The structural violence that Latino immigrants face in the U.S. shapes their experiences. The purpose of this paper is to explore the relationship between structural violence and a patientâ€™s distrust of the biomedical system. A life history was conducted with a 50-year-old Mexican immigrant, Cirila, who had stage 4 chronic kidney disease. The interview was done in the intervieweeâ€™s home after her consent was granted. All of the questions and recorded responses are in Spanish, however, the analysis is in English. Through the life history we found that the structural violence that Cirila faced within the biomedical system created a sense of distrust for the system. This distrust has led her to combine her biomedical treatment with complementary and alternative medicines (CAM) as well as utilizing transnational and informal networks to reconcile their care.

Poster Number: 77


Scripted writing the narrative on women's mental health during the post-deinstitutionalization era

Presenter: Courtney Cantu, History Undergraduate Student

Mentor: Dr. Sarah Rose

Abstract:

"Despite psychiatrists ongoing efforts to make the Diagnostic and Statistical Manual of Mental Disorders as objective as possible, no such classification system can ever be fully value free."� This excerpt from a recent discussion on gender bias criteria in the DSM illustrates, mental health care at its core is a social phenomenon. Drawing on oral histories completed by psychiatric survivors, as well as research group findings and sociological studies, this paper explores gender dynamics in mental health diagnoses and treatment during the post-deinstitutionalization era. While women make up 75% of mental health workers and 62% of mental health service consumers, they are grossly underrepresented at the decision-making levels. Historically, moreover, women have more frequently diagnosed with mental health problems than men. Gender has long proved to be an important predictor in how physicians identify depression, with female patients twice as likely as men to be diagnosed as depressed. Furthermore, sociological studies have shown that when the practitioner and the patient do not share the same gender status, the distance between them will make the practitioner less able to understand the patient’s behaviors. Finally, not only are women more frequently diagnosed, but their treatment plans also more commonly involve prescribed mood-modifying medicines in addition to the therapy. The testaments from psychiatric survivors allows researchers to gain first hand knowledge of life within the walls of the hospitals. The gender dynamics that play out within their stories has been confirmed through many physician research groups, as well as studies on diagnosis and gender.

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