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PSYC2021NGUYEN32570 PSYC

Effects of Neural Manipulation of the Nucleus Accumbens on Reward Loss

Type: Undergraduate
Author(s): Quynh Nguyen Psychology Sara Guarino Psychology Christopher Hagen Psychology Mauricio Papini Psychology
Advisor(s): Mauricio Papini Psychology
Location: Zoom Room 5, 02:23 PM

The current study aimed to investigate the neurobehavioral mechanisms underlying devaluation of expected rewards. In rats, frustration effects of reward loss are produced using the reward downshift (RD) situation. RD postshift phase involves two stages. After an initial suppression of sucrose consumption (Stage 1), behavior recovers to baseline levels (Stage 2). During Stage 1, nucleus accumbens (NAc) neurons release lower levels of dopamine, but it is not known whether they participate in the recovery process (Stage 2). We hypothesized that NAc activity would be important for the recovery process following a 32-2% sucrose downshift. The study explored the role of the NAc by selectively targeting both RD postshift stages using chemogenetics. Inhibitory or excitatory Designer Receptors Exclusively Activated by Designer Drugs (DREADDs) were delivered into the NAc of rats via intracranial infusion and activated prior to downshift sessions via intraperitoneal injection of Clozapine N-Oxide (CNO), the activator drug for DREADDs. Rats were assigned to one of three neural manipulation condition, inhibition (INH), excitation (EXC), or control (CON), and received either CNO or Vehicle (veh) on postshift sessions. Thus, there were two groups in each neural manipulation condition: INH/CNO, INH/Veh, EXC/CNO, EXC/Veh, Control/CNO, and Control/Veh. Preliminary results revealed that NAc inhibition does not disrupt sucrose consumption during RD postshift. However, NAc excitation increases consummatory suppression and slows the recovery process. This pattern of results suggests that the chemogenetic manipulation may be affecting GABAergic projection neurons within the NAc, increasing the suppression of dopamine release, and resulting in suppressed behavioral response.

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PSYC2021NORTHERN37898 PSYC

Lecture Fluency Impacts Instructors' Ratings of Other Instructors' Teaching

Type: Graduate
Author(s): Paige Northern Psychology Addison Babineau Psychology
Advisor(s): Uma Tauber Psychology
Location: Zoom Room 3, 03:35 PM

There are many factors that can impact students’ evaluations of instructors’ teaching. Lecture fluency (i.e., the ease with which a lecture is delivered) is one factor that can impact students’ evaluations. Recently, researchers have examined how fluent lectures (very polished lectures during which the instructor makes appropriate eye contact and exudes confidence) compared to disfluent lectures (lectures during which the instructor does not make eye contact and does not display signs of confidence) impact students’ evaluations of instructors. Students who watch fluent lectures typically evaluate the instructor more favorably relative to those who watch disfluent lectures, even when the content in both lectures is identical (Carpenter, Mickes, Rahman, & Fernandez, 2016; Carpenter, Northern, Tauber, & Toftness, 2020; Carpenter, Wilford, Kornell, & Mullaney, 2013; Northern, Tauber, St. Hilaire, & Carpenter, in prep; Toftness, Carpenter, Geller, Lauber, Johnson, & Armstrong, 2017). All of the research on lecture fluency has focused on students’ evaluations of instructors, but the delivery of a lecture may also impact instructors’ evaluations of other instructors’ teaching. On the other hand, instructors have much experience both watching and delivering lectures, and it is possible that they may rely more on their experience when evaluating instructors rather than the fluency of a lecture. In this study, students and instructors watched a video of a lecture. The lecture was delivered either fluently or disfluently, and the content was the same in both lectures. After watching the lecture video, students and instructors rated the instructor on several evaluation items. Novel to the current study, instructors who watched a fluent lecture gave significantly higher instructor ratings compared to those who watched the disfluent lecture. Replicating prior work, students who watched a fluent lecture gave significantly higher instructor ratings relative to students who watched the disfluent lecture. Thus, the delivery of a lecture rather than the content of a lecture can have a strong impact on instructors’ evaluations of other instructors’ teaching.

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PSYC2021PARRA64393 PSYC

The effects of trait imageability and extrapolation on metacognitive outcomes

Type: Undergraduate
Author(s): Monica Parra Psychology Kaleigh Decker Psychology Charles Lord Psychology
Advisor(s): Charles Lord Psychology
Location: Zoom Room 6, 01:26 PM

Our research lab has found that individuals tend to adopt more extreme attitudes toward an outgroup (i.e., become self-radicalized) when they extrapolate from known to unknown traits about the outgroup. Recent lab findings have also suggested that trait imageability, or the ability to form a mental image of a trait, can influence the effects of extrapolation on self-radicalization, such that people were more likely to become self-radicalized when they extrapolated to traits that were relatively difficult, compared to relatively easy, to form a mental image of. The current experiment examined whether the effects of trait imageability on extrapolation also influence metacognitive outcomes. We found that participants who extrapolated to traits that were difficult to form a mental image of subsequently reported that they knew more about the outgroup, had greater confidence that they knew how the outgroup members would behave, and were more likely to believe the initial information about the outgroup was accurate, compared to participants who extrapolated to traits that were easy to form a mental image of and compared to control participants. The current findings established an important link between and the effects of trait imageability on extrapolation and subsequent metacognitive measures.

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PSYC2021REYES34455 PSYC

Experiences and Challenges of Trust-Based Relational Intervention® (TBRI®) Practitioners in Implementing TBRI with Spanish-speaking Clients

Type: Undergraduate
Author(s): Alex Reyes Psychology Danica Knight Psychology
Advisor(s): Danica Knight Psychology
Location: Zoom Room 1, 01:34 PM

The growing population of Spanish speakers in the U.S. has created challenges related to translating and adapting interventions to serve this diverse population. This qualitative study examined how Trust-Based Relational Intervention® (TBRI®) practitioners currently handle challenges due to language and cultural issues among their primarily Spanish-speaking clients. Eight TBRI® practitioners in 4 different Latin American countries were recruited to complete an online background survey and a 30 to 45-minute virtual interview. Preliminary results indicate that TBRI® practitioners face challenges in regards to their clients’ education level, literacy rates, access to curriculum-related materials, and cultural views on the TBRI® correction principle. Practitioners handle these challenges by simplifying the language used in the materials, explaining content with culturally-relevant examples, creating items that can be used in lieu of ones used in the materials of curriculum, and having patience with clients as they learn a new way of parenting. The goal of this project is not only to bring awareness of translation language barriers and cultural issues with TBRI® materials but to help the Karyn Purvis Institute of Child Development adapt materials, so there is a more appropriate and easily received response to the material among primarily Spanish-speaking children and families.

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PSYC2021SMITH47946 PSYC

Computer-Assisted Foreign Language Vocabulary Instruction

Type: Undergraduate
Author(s): Carson Smith Psychology
Advisor(s): Anna Petursdottir Psychology
Location: Zoom Room 5, 12:38 PM

A foreign language is a non-native language acquired outside of a natural linguistic community. The benefits of learning a foreign language include that it heightens employability, positively affects cognitive functioning, and increases cross-cultural awareness. The goal of this study was to compare the effects of a pair-test (PT) procedure and a high-density response construction (HDRC) procedure on foreign-language vocabulary acquisition. We used a within-subjects pretest-posttest design combined with a single-subject multielement design. Nine participants received instructions with 10 Arabic words; 5 words were taught via HDRC instruction, and 5 via pair-test. We hypothesized that participants would learn faster in the HDRC condition and perform better on transfer and retention tests. However, preliminary results suggest that there was no difference between conditions.

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PSYC2021TOMLINSON23818 PSYC

Evaluating Class Reorganization in Equivalence-Based Instruction

Type: Undergraduate
Author(s): Gregory Tomlinson Psychology Juliana Sequeira Cesar de Oliveira Psychology
Advisor(s): Anna Petursdottir Psychology
Location: Zoom Room 6, 03:11 PM

Previous research evaluated the extent to which equivalence-based instruction (EBI) is more efficient or produces stimulus classes with different properties than complete instruction (CI) in which all relations between stimuli in a class are taught directly. The purpose of the present study was to evaluate the flexibility of the formed stimulus classes in EBI and CI procedures with a contingency reorganization. Forty-eight undergraduate students received training to establish 3 stimulus classes with 4 members in each class. The students were randomly assigned to two groups: EBI – in which they received training for some of the relations – and CI – that targeted all possible relations between the members of each class. After undergoing training and equivalence test (Phase 1), participants received contingency reorganization training (Phase 2). In the reorganization phase, the relations A1B2, A2B3, A3B1 were stablished as correct. Class flexibility was evaluated in an immediate contingency-reversal post-test. The EBI group required fewer training trials to complete ABCD training, and performed similarly to the CI group in the equivalence test. Additionally, EBI group required less training trials in the reorganization training, and performed better in the reorganization test when compared to CI group.

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PSYC2021WESTERFIELD48465 PSYC

Effects of Verbal Disruption on Derived Stimulus Relations

Type: Undergraduate
Author(s): Cullen Westerfield Psychology
Advisor(s): Anna Petursdottir Psychology
Location: Zoom Room 1, 12:54 PM

I examined the effects of disrupting verbal mediation in a task that models the effects of verbally presented information on conceptual behavior. The experiment was done asynchronously by sending participants a SuperLab 6.0 software experiment, requesting a screen recording using Zoom, and acquiring demographic, consent, and exit interview information using Qualtrics. Sixty-four participants were randomly assigned to four conditions. The tact-intraverbal (TI) groups first learned to match visual stimuli with verbal labels, and then to associate pairs of verbal labels. The intraverbal-tact (IT) groups received the opposite sequence. After training, all groups were tested for new relationships between the visual stimuli. One TI group and one IT group were given an additional verbal task during the test, which was predicted to disrupt the performance more in the IT than the TI condition, due to IT participants being more reliant on solving the task verbally. No significant differences in accuracy or reaction time were noted between groups. However, only 47% of those in the IT-V group and 13% of those in the TI-V group actually performed the additional verbal task. The experiment should be repeated through real-time video calls or in person, so that participant instruction-following can be monitored and intervened on.

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PSYC2021WILLIAMS556 PSYC

COVID-19 and Asian Attitudes

Type: Undergraduate
Author(s): Jordan Williams Psychology Olivia Egloff Psychology
Advisor(s): Cathy Cox Psychology
Location: Zoom Room 2, 03:03 PM

COVID-19, an unprecedented virus that shifted into a global pandemic almost a year ago, has greatly impacted the human way of life. Recent research, however, has shown that in the United States discrimination towards people of Asian descent has risen dramatically. From a terror management perspective, this heightened discrimination might be due to a defense mechanism to buffer death-anxiety through enhancing one’s cultural belief. The current study evaluates whether priming thoughts of COVID-19 leads to heightened death-related thoughts and increased racism towards Asians (i.e., worldview defense). Data was collected from 175 Amazon Mechanical Turk (MTurk) workers. Our findings suggest that COVID did not influence attitudes toward Asians and international communication through increased mortality awareness. The current work will discuss possible limitations and directions for further study.

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PSYC2021YRAGUEN14242 PSYC

The role of multi-scripturalism on novel orthography learning

Type: Undergraduate
Author(s): Malia Yraguen Psychology Vishal Thakkar Psychology
Advisor(s): Tracy Centanni Psychology
Location: Zoom Room 5, 02:47 PM

The United States is an increasingly diverse country with respect to the number of languages spoken (Shin & Ortman, 2011). With this increase, many adults experience benefits in their personal or professional lives from learning to read in a new language. However, learning to read fluently is increasingly difficult in adulthood (Abadzi, 1996; 2012) Previous research has shown a general bilingual advantage for novel word learning, such that individuals who are fluently bilingual more easily acquire additional languages (Kaushanskaya & Marian, 2009). Given that the reading and language networks largely overlap (Monzalvo and Dehaene-Lambertz, 2013; Stevens et al., 2017; Wang et al., 2020), we hypothesized that reading fluently in multiple print systems (multiscripturalism) may provide a similar advantage. Thus, we investigated the effect of multiscripturalism on novel letter-sound learning in young adults. Data were collected from young adults at TCU and the larger DFW community. Participants were screened for eligibility through a background questionnaire and a short assessment session conducted over Zoom. Eligible participants completed a 30-minute training session to learn eight Hebrew consonants and vowels. Immediately after training and seven days later, participants completed multiple reading measures to assess letter-sound learning performance (Thakkar et al., 2020). We will present our findings from the first wave of data collection, including the impact of baseline reading on learning and whether existing print systems impacted learning and retention of novel letters. We will also discuss implications for this work on literacy education policies and impacts on those with poor reading skills.

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BIOL2020CALLAGHAN17688 BIOL

Discovering Novel Genes that Allow Bacillus anthracis to Survive Host Defenses

Type: Undergraduate
Author(s): Lauren Callaghan Biology Taylor Kelly Biology
Advisor(s): Shauna McGillivray Biology

Bacillus anthracis is a bacterium that causes the deadly disease anthrax and has been used in bioterrorism. We are looking to investigate what genes within the chromosomal DNA contribute to the virulence of Bacillus anthracis. In this study, we screened a transposon library of B. anthracis ‘knock-out’ mutants for susceptibility to reactive oxygen species used by the immune system. A broad in vitro hydrogen peroxide screen was performed on 1,953 transposon mutants, and after several rounds of in vitro screening, 40 mutants were identified as consistently attenuated in the presence of hydrogen peroxide. Four of these mutants were then tested in the invertebrate model, Galleria mellonella, to assess virulence in an animal model. Mutants with phenotypes that repeated in both assays were prioritized for characterization. The location of the transposon insertion in one of the mutants was successfully identified. Identifying these novel genes contributing to the bacterium’s virulence will provide a better understanding of B. anthracis pathogenesis and may provide potential targets for combatting anthrax.

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BIOL2020ELLIS7230 BIOL

The role of SigM and GlpF on cell wall active antibiotic susceptibility in Bacillus anthracis Sterne

Type: Undergraduate
Author(s): Graham Ellis Biology
Advisor(s): Shauna McGillivray Biology

The bacterium Bacillus anthracis, the causative agent for the disease anthrax, possesses two plasmids that contribute significantly to virulence. Besides plasmids, certain chromosomal genes also contribute. In previous studies, our lab discovered that the chromosomally encoded ClpX gene is essential for virulence in B. anthracis. ClpX is an ATPase that is part of the ClpXP proteasome found in many bacteria. Loss of ClpX in B. anthracis Sterne results in increased susceptibility to cell wall targeting antibiotics like penicillin and daptomycin. However, the mechanism behind ClpX’s role in antibiotic resistance is not understood as it is likely that multiple pathways are affected by the loss of this global protease. We recently conducted a microarray to find which genes are up or down regulated in ClpX compared to wild-type (WT) B. anthracis. 119 genes had disrupted regulation and several of these had been connected to cell-wall active antibiotics like penicillin. In this study, we focused on three of these genes: MsrA, GlpF, and SigM. We confirmed the microarray results and showed that MsrA, GlpF, and SigM gene expression in our ClpX strains significantly differs from the wild-type B. anthracis Sterne via QPCR. Insertional knockout mutants were made for GlpF and SigM to test whether these genes were necessary for antibiotic resistance. We are currently testing these mutants in penicillin and daptomycin to assess their phenotypes. We found that loss of SigM results in increased susceptibility to penicillin and are currently studying the effect of daptomycin on SigM and GlpF. We will test the virulence of both mutants in our invertebrate animal model G. mellonella. This will hopefully provide better understanding on the mechanism behind ClpX’s antibiotic resistance.

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BIOL2020FINCH42215 BIOL

Investigating sex-based differences in pathogen resistance and immune responses in the fathead minnow (Pimephales promelas)

Type: Undergraduate
Author(s): Miranda Finch Biology Lynsey Malin Biology Leah Thornton Hampton Biology
Advisor(s): Marlo Jeffries Biology

Studies have shown that males and females differ with regard to their ability to survive pathogen infections. The fathead minnow is a newly developed model for immunotoxicity; however, few studies have compared male and female immune responses following pathogen exposure. The purpose of this study was to examine sex-based differences in pathogen resistance and immune responses following exposure to a pathogen in adult fathead minnows (Pimephales promelas). To accomplish this, fish were bacterially infected with Yersinia ruckeri and the immune system’s ability to respond was monitored. Additionally, genes that are known to be expressed during the immune response initiation were measured quantitatively, providing insight into the molecular effect in minnows. At the whole organism level, male fish were less able to survive pathogen infection relative to female fish. At the tissue level, both male and female pathogen-injected fish had decreased hematocrit percentages compared to the fish injected with a saline solution, but did not differ from each other. At the molecular level, increased gene expression of interleukin 1β was seen in pathogen-injected males compared to pathogen-injected females and both sham-injected sexes, indicating that pathogen-injected males mounted a larger inflammatory response at the molecular level. Taken together, this evidence suggests that the increased mortality observed among males earlier in the exposure to the pathogen may be due to the upregulated inflammatory response rather than the effects of the pathogen itself.

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BIOL2020KANG53827 BIOL

Effects of Pollen Limitation on Seed Production in the Pale Pitcher Plant

Type: Graduate
Author(s): Karis Kang Biology John Horner Biology
Advisor(s): John Horner Biology

Pollen transfer among flowers contributes to genetic diversity and the maintenance of plant populations through the production of seeds. Decreased pollen receipt can result in fewer offspring. This is known as pollen limitation. We conducted field and laboratory experiments in a population of Sarracenia alata in Leon County, Texas in 2019 to examine 1) the effect of floral herbivory by the pitcher plant moth, Exyra semicrocea, on pollen availability and 2) the impact of pollen receipt on seed quantity and 3) seed quality. We found that floral herbivory significantly decreased the number and mass of anthers in flowers, and that a high pollen load significantly increased the number of seeds produced compared to low-pollen and control flowers. We found no differences in offspring quality among different pollen treatments based on germination traits. Pollen limitation occurs in S. alata and may pose a conservation risk when paired with other ecological disturbances.

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BIOL2020KELLY29623 BIOL

Discovering Novel Genes Important for Survival Against Reactive Oxygen Species in Bacillus anthracis

Type: Undergraduate
Author(s): Taylor Kelly Biology
Advisor(s): Shauna McGillivray Biology

Bacillus anthracis is a gram-positive, spore-forming bacterium and the causative agent of the deadly disease anthrax. The B. anthracis genome consists of chromosomal genes and the pXO1 and pXO2 plasmids that strongly contribute to the bacteria’s deadly nature. While the virulence factors associated with the plasmids have been extensively studied, we believe there are still undiscovered chromosomal genes that may also have important virulence factors. To identify novel chromosomal genes associated with B. anthracis virulence, we screened a transposon mutant library of B. anthracis Sterne strain for increased sensitivity to reactive oxygen species. Reactive oxygen species, such as hydrogen peroxide, have many functions in mammalian immune defenses and wild type B. anthracis is able to subvert this host defense. Sensitivity to reactive oxygen species was tested through in vitro hydrogen peroxide assays and after several rounds of screening, eight mutants were confirmed as susceptible. We next tested whether any of these mutants were attenuated in vivo using our invertebrate animal model, Galleria mellonella and found several mutants with decreased virulence. We are currently working on determining the location of the transposon insertion to find which chromosomal gene is disrupted. This could lead to the discovery of novel B. anthracis virulence genes and eventually possible treatment targets for future anthrax outbreaks and attacks.

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BIOL2020LAMANTEER44511 BIOL

Comparison of Swim Performance Assays for Evaluating the Cardiovascular Fitness of Larval Fathead Minnows

Type: Undergraduate
Author(s): Gabriella Lamanteer Biology
Advisor(s): Marlo Jeffries Biology

The swim performance assay is a behavioral assessment used to measure cardiovascular function in fish. Previously, the laminar flow assay (LFA) has been the standard method of assessing swim performance in adult fish to measure their cardiac output. The spinning task assay (STA) is a novel, accessible method of assessing swim performance; however, previous studies have not compared the two methods. Additionally, there is little documentation of swim performance in larval fish, a more sensitive study subject for toxicological research. Therefore, the aim of this research is to compare the swim performance of fish in the LFA to those in the STA to determine which method is better for assessing swim performance in larval fathead minnows (Pimephales promelas). In this study, the percent of fish that fail to swim in the LFA is inversely proportional to the age of the fish, but in the STA, there is no correlation between percent failure and fish age. Results show that as fish increase in size, swim performance in the LFA improves, making it a more representative, predictable assay. Results from the STA indicate that swim performance in fish does not improve with size and performance in the STA is not correlated with performance in the LFA. Ucrit values from the LFA have less variation than those from the STA. The results of this study show that the LFA is a more suitable modality for assessing swim performance in larval fathead minnows.

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BIOL2020SCHENK25315 BIOL

Predator-Prey Dynamics in an Urban Forest: Assessment Using Raptor Predation on Prey Mimics

Type: Graduate
Author(s): Amber Schenk Biology Amanda Hale Biology Tom Stevens Biology
Advisor(s): Amanda Hale Biology

Predator-prey dynamics play an integral role in shaping and regulating wildlife communities; however, recent studies have shown a decoupling of these relationships in urbanized areas. Trickle-down effects from the disruption of this trophic interaction have the potential to produce impacts that are far-reaching, altering other critical dynamics within the ecosystem. The purpose of my study was to characterize raptor activity and levels of predation in a large urban forest, the Great Trinity Forest in Dallas, TX. To quantify the extent of urbanization, I used ArcGIS Pro’s (version 2.2.0) image classification wizard with supervised, object-based classification on 50-cm pixel resolution, multi-band remote sensing imagery to estimate the percent of impervious surface. Then, from May to August 2019, I conducted weekly raptor surveys and deployed urethane foam prey mimics (snakes and mice) at 18 survey locations along an urban-to-rural gradient within this forest. In total, I detected 161 raptors representing 8 species throughout the season and found no relationship between raptor activity or diversity and degree of urbanization. Of the 732 prey models deployed, 61 showed signs of being depredated whereas 23 were missing and therefore had an unknown fate. Similar to the raptor results, overall predation on mice and snake models showed no relationship with degree of urbanization. Based on markings on the depredated models and photographs from field cameras, raptors appeared to target the snake mimics with no evidence of predation attempts on mice. And finally, I found no significant relationship between raptor activity and predation on snake models. Collectively, these results suggest either increasing levels of urbanization have no effect on raptor-prey dynamics within the Great Trinity Forest or there is low predatory response from raptors in regard to prey mimics.

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BIOL2020TUCKER51048 BIOL

Ectoparasite loads of Texas horned lizards (Phrynosoma cornutum) living in small towns

Type: Graduate
Author(s): Mary Tucker Biology Stephen Mirkin Biology
Advisor(s): Dean Williams Biology

Ectoparasites are a vital but often overlooked part of ecosystem dynamics, which have been shown to be negatively correlated with growth and decreased body condition in various vertebrate species. Texas horned lizards living in natural environments are known to harbor red mites (Acarina sp.), but the impact and density of these mites on lizards living in urban environments is not well known. Using weekly surveys during the summer of 2018, we examined the ectoparasite loads on Texas horned lizards (n = 87) from 11 different sites in Kenedy and Karnes City, Texas. We counted mites and recorded where they were found on the lizard’s body. We also determined the sex, age (juvenile versus adult), and body condition (body weight/SVL) of each captured lizard. We found significant differences in the number of mites between males and females, with males exhibiting heavier parasite loads, and also between different sites within the same town. We found no correlation between body condition and number of mites present. We present the first known research of ectoparasite loads of Texas horned lizards from an urban environment. Although the sample size is small, our data suggest that ectoparasite loads of Texas horned lizards from natural environments have lower mite loads than lizards found in an urban environment. These findings deserve further exploration to see if urban environments play a role in increased parasitism.

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CHEM2020BUDENSIEK51413 CHEM

Fabrication and Characterization of Sub-Micron Plant-Derived Silicon Nanoparticles for Drug Delivery

Type: Undergraduate
Author(s): Hailey Budensiek Chemistry & Biochemistry
Advisor(s): Jeffery Coffer Chemistry & Biochemistry

Porous silicon nanoparticles exhibit great potential as drug delivery vectors due to their high surface-area-to-volume ratio allowing for increased efficacy of surface functionalization and therapeutic loading capabilities. This data set demonstrates the fabrication of a class of plant-derived materials which are sub-micron in size and capable of functionalization with primary amine groups through the addition of APTES.
The production of porous silicon particles (pSi) is achieved through magnesiothermic reduction of silica containing Tabasheer powder isolated from the nodal joints of the Bambuseae plant. Efficacy of this reduction is evaluated using techniques including X-ray diffraction and Energy-dispersive X-ray spectroscopy which show successful reduction of silica starting material to porous silicon.
High energy ball milling followed by reduction is used to produce pSi particles of sub-micrometer size while also allowing for a significantly higher yield (~90%) of material than previous methods. Particle size is confirmed via electron microscopy and dynamic light scattering (DLS).
Following reduction, surface functionalization of silicon nanoparticles with primary amine groups was carried out using a 4% (v/v) solution of APTES in acetone. The evaluation of this functionalization was conducted using techniques including zeta potential and infrared spectroscopy (IR). Zeta potential values are found to be approximately -10 mV. This data demonstrates successful amino silanization.
The results achieved through these methods suggest successful fabrication of pSi nanoparticles and subsequent functionalization for future use as a drug delivery vector.

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CHEM2020GOEHRING48218 CHEM

Creating Biocompatible Polymers Loaded With Porous Silicon Potentially For Drug Delivery

Type: Undergraduate
Author(s): Lexi Goehring Chemistry & Biochemistry
Advisor(s): Jeff Coffer Chemistry & Biochemistry

Drug delivery is the process by which medications are administered to the body. This is complex due to the difficulty of determining compounds that have the proper biocompatibility and permissibility to our human cells. Many medications are taken orally; however, there are advantages to administering medication subcutaneously or by inserting it in the inner corner of the eye. Porous films made out of biocompatible polymers provide a good platform for drug delivery as they have the ability to be loaded with plant derived porous Silicon. Functionalizing the porous silicon using (3-aminopropyl)triethoxysilane and glutaraldehyde can be done in an attempt to covalently attach particles to the film which is important for embedding them into the pores of the film. Porous silicon has biocompatible properties and can be loaded with drugs then modified to alter the release of those drugs in the body. This method has the potential to be a useful drug delivery method due to the biocompatible and biodegradable properties of the material and the ability to manipulate the material in order to maximize drug release.

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CHEM2020LE35772 CHEM

POROUS SILICON NANOTUBES AS POTENTIAL VECTORS FOR SMALL INTERFERING RNA DELIVERY

Type: Graduate
Author(s): Nguyen Le Chemistry & Biochemistry
Advisor(s): Jeffery Coffer Chemistry & Biochemistry Giridhar Akkaraju Biology

In cancer therapy, nucleic acid-based therapeutic strategies have been extensively investigated to suppress mutated gene expression, thereby inhibiting cancer cell growth. Among the approaches, small interfering (siRNA)-mediated gene silencing has been envisaged as a promising therapeutic approach to silence specific gene expression by targeting mRNA of the unwanted gene for degradation, thereby readily controlling cellular functions. However, delivery of small interfering RNA (siRNA) has been known to encounter multiple challenging barriers, such as blood circulation and cellular internalization, thus limiting the potential merits of this therapeutic strategy. While non-viral vectors have been preferred owing in part to better immune system compatibilities, porous silicon (pSi) with various geometric shapes (e.g. platelet and discoid) have recently been demonstrated as exceptional delivery carriers of siRNA in various disease models. Here our initial in vitro studies show that silicon in a unique one-dimensional porous nanotube structure (pSiNTs) can serve as a promising vector for delivery of siRNA to limit target gene expression, thereby expanding the library of possible nanostructures of Si in delivery of siRNA.
In this work, we demonstrate that pSiNTs after being functionalized with 3-(aminopropyl)triethoxysilane (APTES) can deliver enhanced green fluorescence protein (EGFP)-targeting-siRNA via electrostatic conjugation and suppress EGFP expression in HeLa cervical cancer cells by up to 50%. Cytocompatibility and biodegradation of the functionalized pSiNT matrix upon siRNA delivery are characterized by ATP quantification assays (CellTiter Glo) and Transmission Electron Microscopy imaging (TEM) respectively. These results encourage further development of pSiNTs in therapeutic applications.

(Presentation is private)

CHEM2020SEGURA63908 CHEM

Synthesizing a vaccine for the treatment of addiction to the fentanyl opioid

Type: Undergraduate
Author(s): Carolina Segura Biology
Advisor(s): Jean-Luc Montchamp Chemistry & Biochemistry

The objective of this project is to make a vaccine that will negate the effects of the powerful opioid fentanyl in the long term. Fentanyl is a strong synthetic opioid that is 50 to 100 times more potent than morphine. According to the CDC, there were over 70,000 deaths due to street drug overdoses, which has increased in the last ten years. 40 % of these deaths are related to fentanyl overdoses, therefore it is imperative that approaches are developed to combat this alarming increase in deaths. The vaccine against fentanyl will be synthesized out of molecules that will take advantage of fentanyl’s amide functional group to be hydrolyzed into safe byproducts. Any patient that is administered with the vaccine, will not feel the effects of the opioid because the immune system will hydrolyze the drug as soon as it enters. This project will exploit the properties of both catalytic antibodies (CAbs) and transition state analogs. The Cabs will trigger an immune response to attract phagocytic cells, such as macrophages to phagocytose pathogens and eliminate them from the system. However, if the molecule resembles the transition-state of fentanyl hydrolysis, then the antibodies can cleave the fentanyl in a fast and efficient manner due to their catalytic properties. Therefore, after immunization, a person who is addicted to fentanyl would no longer feel the effects of the opioid because it will be degraded as an immune response is triggered, creating a long-term possible solution to one factor of the “opioid crisis.”

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COSC2020SMITH56615 COSC

Sir Stan's Well Rounded Adventure

Type: Undergraduate
Author(s): Brooke Smith Computer Science Nick Bonavia Computer Science Sellars Levy Computer Science Shane Mitchell Computer Science David Rasberry Computer Science Westen Riley Computer Science
Advisor(s): Michael Scherger Computer Science

Sir Stanley’s Well Rounded Adventure is a mobile game that is meant to help educate children ages 7-11 about living a healthy lifestyle. Childhood obesity is on the rise, and while we cannot control the lifestyle choices others make, we can help bring education to the younger masses through a medium that they can enjoy: video games. Sir Stanley’s Well Rounded Adventure will help children learn valuable lessons about nutrition and physical activity through a series of unique mini-games, in-game tutorials, and in-game achievements. Our goal is to make this information that has been provided to us by TCU’s nutrition department both accessible and easy to understand for the younger generation.

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ENSC2020AGPALO34894 ENSC

Improving habitats for bats: What makes a bat-friendly residential swimming pool?

Type: Graduate
Author(s): Elizabeth Agpalo Environmental Sciences
Advisor(s): Victoria Bennett Environmental Sciences

For urban environments to support bat communities, resources need to be readily available, such as water. For example, bats typically use urban water sources, such as drainage ditches, lakes, and ponds. However, in areas where temperatures are consistently high and rainfall limited, these sources tend to be ephemeral. During these periods, bats utilized residential swimming pools. If pools were more attractive to bats, we may be able to improve urban habitats for bats both in terms of abundance and species diversity. We, therefore, set out to determine whether size, shape (round of square), lighting, and treatment type (chlorine, salt, or mineral) encouraged bats to drink at pools. Thus, we conducted behavioral surveys at 14 pools using thermal cameras and acoustic detectors to record bat foraging and drinking activity. Our results demonstrated that while shape did not influence pool use, treatment type, lighting, and size did. With this information, we can better advise interested residents in urban neighborhoods how better to make their backyards more bat-friendly.

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ENSC2020ISHIMWE15686 ENSC

The potential of cost-effective UAV technology to replace costly technologies in Precision Agriculture

Type: Undergraduate
Author(s): Benite Ishimwe Environmental Sciences
Advisor(s): Esayas Gebremichael Geological Sciences

The potential of cost-effective UAV technology to replace costly technologies in Precision Agriculture

Abstract

The use of satellite and aerial remote sensing for agricultural applications has exponentially expanded since the past decades. One such agricultural application that is highly dependent on the use of advanced hyperspectral and multispectral remote sensing and GPS technology to boost crop harvests and viability, while reducing the number and amount of inputs, like water, fertilizer, land, and others required to grow crops, is Precision Agriculture (PA). Although PA has been credited for the increased crop yield and productivity in the United States and worldwide, its dependence on costly technologies has been a major hurdle for it to be used by small-scale farmers locally and globally. This project aims to reduce the dependence of PA on costly and complex remote sensing technologies through the use of alternate and cheaper options such as low/medium-priced Unmanned Aerial Systems (UAV), popularly known as drones, equipped with only high-resolution cameras capable of, to a certain extent, mimicking the functionalities that are offered by costly technologies. Such low-cost technology is anticipated to enhance the efficiency and profitability of the agriculture sector through the provision of easier technologies to small-scale farmers. The research project is currently being implemented on a wheat farm owned by Davis farms (Grandview, Texas). Multi-temporal (at different growing stages) UAV imageries using DJI Mavic air 3D are being acquired with the purpose of producing 3D maps for qualitative and quantitative analysis. This includes crop-health assessment through the generation of crop-health indicator indices such as the Normalized Difference Vegetation Index (NDVI). A similar analysis from high-resolution multispectral imagery of the area, acquired from commercial satellite operators, will be undertaken and the accuracy, validity, and reliability of the UAV-based PA application will be assessed.

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ENSC2020ISHIMWE6062 ENSC

The effects of increased population growth on Rwanda’s forest ecosystem

Type: Undergraduate
Author(s): Benite Ishimwe Environmental Sciences
Advisor(s): Esayas Gebremichael Geological Sciences

The effects of increased population growth on Rwanda’s forest ecosystem.
Rwanda is a country in Central-East Africa and one of the smallest countries on the African continental, being only 10,169 mi²/ 26340 sq. Km. Rwanda is a landlocked country bordered by Uganda, Tanzania, Burundi, and the Democratic Republic of the Congo. The current population of Rwanda is 12,830,205 as of 2020, based on the latest United Nations data with a population density of 525 per Km2 which equates to about 1,360 people per mi2 with 17.6 % of the population living in urban centers.
Rwanda forests have historically played a very significant role in the economy and livelihoods of its population through tourism, energy, and other industrial purposes. They provide around 86% of the primary energy source mainly as domestic cooking energy. Rwanda experienced 50.9% total forest loss since 1990, in order to address this deforestation and imbalance in wood supply/demand, Rwanda has over the years taken a consistent stance on increasing the forest cover by 30% by 2020. With growing population, this case study is going to analyze how population growth in Rwanda has affected forest cover and biodiversity. The study will integrate available geospatial datasets such as census, infrastructure, and satellite imagery to assess the impact of population growth on deforestation.

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