Past Symposia Presentations – University of Mary Washington Sciences

2023 Fall Research Sympoisum

The following courses were offered in Fall 2023 and have students presenting their work in this symposium.

BIOL 322 Animal Ecology, Dr. Brad Lamphere
Animal Ecology studies how animals interact with their world and one another. Our lab exercises collect data on five topics ranging from ant foraging strategy to fish population estimation to invertebrate community diversity. For the lab final, students use one dataset to analyze and answer an original scientific question.

The following are the projects presented in this symposium:

Poster 1: How Gear Selection Influences Fallfish and Bluegill Catch in Alum Spring Park
Taylor Nicholson

Accurately assessing the true population of a species within an environment, particularly in expansive and mobile ecosystems, poses a considerable challenge. To estimate population size and its characteristics, a representative portion of the population must be sampled. Various methods, such as seining or electrofishing, are employed to capture individuals from aquatic populations and examine population dynamics. In Alum Spring Park, Fredericksburg, Virginia, both Lepomis macrochirus (bluegill) and Semotilus corporalis (fallfish) inhabit the same stream but occupy distinct habitats. My investigation aims to explore the potential influence of gear selection on the length of individuals captured, specifically focusing on fallfish and bluegill. The survey involved using seining nets to sample an approximately 85 meter stretch of the stream, followed by a survey using a backpack electrofisher along the same course. I anticipate that electrofishing will yield a larger average fish length for both species compared to seining. This assumption is based on the idea that electrofishing has the capacity to stun larger fish, while larger, more robust fish may evade seining due to their strength and adaptive behavior. Additionally, fallfish are inclined to favor pools, whereas bluegill tends to seek shelter in rocky or vegetated areas, resulting in distinct preferences that affect each species’ catchability which could be influenced by length. This investigation is critical in ensuring a comprehensive representation of the population, particularly considering the varying body types and habitat preferences among these fish species.
Poster 9: The Influence of Food Availability on Dietary Preferences in Little Black Ants and Carpenter Ants
Anias Saunders

Carpenter ants and Little black ants are two ants species that are native to Fredericksburg. Ant species’ trophic niches are mostly determined by their dietary preferences, which also have an impact on how these animals interact with one another and the general organization of ant communities. Ecologists can learn more about the competitive relationships, resource distribution, and ecological roles of various ant species within an ecosystem by analyzing food preferences. In this experiment, I investigate what are the nutritional preferences between little black ants and carpenter ants. They were given the choice of a cookie, jam, and tuna over a period of 45 minutes. Each ant was recorded in 5 minute intervals at each food station. Carpenter ants were found more with the cookie and tuna while the little black ants were found at the cookie and jam. These results suggest carpenter ants being carnivores prefer a source of food with some protein whereas the little black ants prefer sugar in their food.
Poster 13: Rural vs. Urban Species Abundance and Richness in Eastern Virginia
Rachael Harrington and Meghan Ponton

With the spread of urbanization, understanding how species navigate and utilize resources is necessary to identify the impacts of urbanization on these locations. This study looks into the influence of urbanization on species abundance and richness in urban and rural areas in Eastern Virginia. We hypothesize that the rural study location will have increased diversity and abundance, likely because of the continuous habitat availability. We predict urban environments to have lower values because of limited habitat availability and size. We analyzed camera trap data and identified species and behaviors that were placed in camera traps at Crow’s Nest Natural Area Preserve and the Virginia Outdoor Center during the fall of 2023 in Eastern, VA. Preliminary observations show that species abundance is higher in rural settings compared to the urban study location at the Virginia Outdoor Center. This research contributes valuable understandings of species interaction and presence in an urban and rural ecosystem to develop effective management plans for biodiversity conservation. As urbanization spreads into rural areas, understanding species abundance and richness dynamics is essential for developing strategies to protect and preserve vital habitats and ecosystems.
Poster 16: Effect of Food Source Nutritional Content on Little Black Ant Foraging Behavior
Kylie Steffenhagen

Interactions between species and their role in food webs are integral to ecosystem dynamics, and yet are areas of ongoing research in which our understanding is limited. The foraging behavior of ants provides an opportunity for insight into the function of food webs at the smallest scale. How does the nutritional content of different available food sources influence the foraging behavior of the Little Black Ant (Monomorium minimum)? This study was conducted in both forest and open field sites of the University of Mary Washington campus, near the Jepson Science Center. Three food samples of varying nutritional content – including tuna (protein), jelly (sugar), and cookies (protein & sugar) – were set out and observed. Data recorded from the Fall 2023 study, as well previous years (2019-2022), was compiled and analyzed for ant abundance patterns. It is expected that that the Little Black Ant, which is known to be an omnivorous scavenger, will display a preference for food samples containing both protein and sugar. By achieving a greater understanding of the foraging habits of species like the Little Black Ant, we can identify the role of each species in its larger food web, and we develop the tools required to undertake effective ecosystem conservation and restoration efforts.
Poster 20: Does the amount of rain effect the number of fish caught each year in alum spring?
Rebecca Baker

Rainwater that falls onto the ground collects particles and nutrients (nitrogen and phosphorus (Gilbert et al., 2005)) as it flows across the ground and into either aquafer underground or storm drains to streams. These nutrients then make their way into waterways where the nutrients can accumulate and produce algae blooms. Algae is good at a moderate amount because they are food for fish; either directly in the case of central stonerollers (Sublette et al., 1990) or indirectly being food for insect/insect larvae which are food for fish (in.gov.; Pinder, 2023). Using annual rainfall data compared to the number of fish that were caught at alum spring creek every year, it is hypothesized that the more rainfall that there has been in a season, the more fish that will be caught. I expect that for years with a higher amount of rainfall for there to be more central stonerollers, bluegill, and fallfish caught in Alum Spring. Uncontrolled increase in nutrients in waterways can lead to an overproduction of algae. This overproduction of algae will cause eutrophication, which leads to fish die-offs from lack of dissolved oxygen and can have catastrophic effects on the marine ecosystem.
Poster 24: Temporal changes in day-night distribution of animal taxa
Paul James Solis

Many mammals are either diurnal or nocturnal, although these are not restrictive conditions. Species who may have an innate preference for certain hours may shift over time due to competition and/or predation. The ratio of species found in daylight to total species in both day and night was then calculated to estimate this preference. Individual trail cams were placed separately within Virginia Outdoor Center during Fall 2023. Footage of nearby peanuts and surrounding open area was taken at time intervals. Species data (either day or night) from 2017, 2019, 2021 was used for Crow’s Nest; data from 2019, 2020, 2022, 2023 was used for Virginia Outdoor Center. The null hypothesis was that there were no changes in day-to-total ratio of all animal taxa, even after some species were introduced in later years. The results showed that for all animal taxa at VOC, the slopes of the regression lines were significantly close to 0. As for Crow’s Nest, squirrels and coyotes had significant p-values (0.035 and 0.004, respectively), while the other taxa had insignificant findings. Linear regression analysis was able to determine significance via p ≤ 0.05. Determining potential differences between individual species under a taxa may be needed, but most taxa as a whole did not change in day-to-total ratios.
Poster 27: Predicting Fish Populations: Do Longer Fish one year Predict More Fish the Next year?
Samuel Gibbins Brown, Samuel Preston Trevey

Modeling populations and predicting population changes year to year are important questions that biological scientists and ecologists attempt to answer across a variety of plant and animal populations of concern. Researchers will analyze available data from multiple yearly surveys of Hazel Run creek in Fredericksburg, Virginia and attempt to correlate mean fish length of a given species with the number of fish of the same species surveyed in the next year. Previous research from Barneche et al indicate that larger fish spend disproportionately more energy on reproduction than do smaller fish. Hazel Run survey data do not include weight, so researchers propose using length, a metric that was collected in the survey data, in an attempt to test this assertion. Evidence supporting the hypothesis will be positive correlations in data comparing mean fish length one year to number of fish of the same species surveyed the next year. Researchers predict that longer fish will on average weigh more, and if Barneche et al are correct, these fish will produce more offspring on a year to year basis.
Poster 32: Effect of Different Fishing Methods on Various Species of Fish over Time
Dewey Snyder

Over the previous seven years, both seining and electrofishing have been used to fish in Hazel Run, both with varying success rates on the species that inhabit Hazel Run. Time is not a considered factor in the equation, and so the calculations run tests whether or not the percent of certain fish species caught via seining vs. electrofishing has significant variance over the course of seven years. To test this, five species of fish present across all seven years were chosen and the catch numbers were converted to percentages for each type of fishing. The effectiveness percentages were then compared on the scale of time from 2016 to 2023. Of the five species examined, the bluegill had percentages that remained relatively steady across seven years; the fallfish and the largemouth bass had percentages that fluctuated across seven years with no discernable pattern; and the bluehead chub and the redbreast sunfish had potentially significant rises and falls in the percentages across seven years.
Poster 35: Mammal’s Recorded on Trail Cameras in Relation to Distance from Human Habitats
Hunter Garnett

The encroachment of human development onto forested areas will increase the interactions between humans and animals. Previously published research by (Soergel) states that human disturbance can alter the behavior of mammals to become bolder in the face of human development as in the case of raccoons, or they can avoid dense human development as in the case of bobcats. I aim to determine if distance from human development has an effect on the mammalian species captured on trail cameras. To test my hypothesis that cautious mammals prefer to distance themselves from human development, trail cameras were set up on the Virginia Outdoor Center’s wooded trail. Each trail camera was placed several meters off of the trail and into the woods positioned one to two feet off of the ground. In order to increase the success of capturing mammals on the trail cameras whole peanuts were used as bait. The trail cameras were then left out for exactly one week to collect images. I expect that the data collected from the trail cameras will support my hypothesis that there would be a difference in mammalian species captured based upon the distance from human development.
Poster 45: The correlation between fish length and pass number
Aleksandra Witkowski

Fish can vary in size and withstand different amounts of electricity depending on length. Larger fish are known to withstand more voltages of electricity when compared to smaller species. This topic addresses the benefits of using electrofishing as a sampling method and helps to identify if the average length of species caught is affected while using this method. This study asks the question of if there is a correlation between the length of fish caught and the pass number in which they were captured. Data was collected using an electro fisher, nets, buckets, as well as a solution that temporarily calmed the fish in order to be measured. A sample area was measured out in the Hazel Run Creek, and a pass was done through the water in the sample area in order to collect data. The data shows that there is no noticeable trend in which the pass number relates to the average length of species caught. The hypothesis was not supported, and as pass numbers increase, there is no correlation to the average length of species caught. Based on the data, when using the electrofishing technique there is no disadvantage as a sampling method when collecting average lengths.

BIOL 432 Virology, Dr. Lynn Lewis
In this Research Intensive course, students are introduced to the major groups of viruses and their replication cycles, lab techniques for studying viruses and some of the new, emerging viruses. Students practice lab techniques for handling, growing and studying viruses during the first half of the semester, while designing an experimental research project based on their reading of primary literature. Students then carry about their research projects, in groups of 2 or 3, during the second half of the semester and present their collected data analysis.

The following are abstracts for the projects presented in this symposium:

Poster 3: Antiviral Effects of Chlorpromazine Against NDV in BHK-21 Cells
Aisling Berrios, Jenny Vuong, Cyrus Ramsey

In today’s world, with the COVID-19 pandemic and extremely high antiviral prices, there has been a push for new, novel antiviral treatments. Newcastle Disease Virus, or NDV, is a detrimental virus to poultry and can cause extreme economic loss for the poultry industry. Our research project aimed to investigate the properties of the antipsychotic drug, chlorpromazine, as an antiviral against NDV in BHK-21 hamster cells. The goals of our research were two-fold, to contribute to the current knowledge of NDV treatments, and to potentially relate this to other viral respiratory diseases such as COVID-19. We hypothesized that chlorpromazine will exhibit antiviral effects against NDV, resulting in an decrease of cell death due to NDV infection. To do this, we performed a TCID50 assay to determine the cytotoxicity of the drug using chlorpromazine concentrations of 5, 7, and 9µM. Due to difficulties with the incubator, we were delayed in our experimental procedures. Thus, we will be performing an MTT assay at a later time to investigate the potential benefits of using chlorpromazine as a treatment. Statistical analysis of this test will be done through a one-way ANOVA. Our cytotoxicity assay found that none of concentrations were cytotoxic to the cells, with chlorpromazine at a 5µM concentration proving to be the most viable. Analysis is ongoing.
Poster 6: Antiviral Effects of Echinacea purpurea on NDV in BHK-21 Cells
Jessie Mills and Kinsey Brotman

Newcastle disease virus (NDV) is a deadly paramyxovirus that can affect the respiratory system in chickens. E. purpurea is an herbal supplement that has been proven through numerous studies to have antiviral properties. Expanding research on the antiviral effects of E. purpurea is
important because it is easily accessible and may help decrease viral spread. The question being tested is if E. purpurea can act as an antiviral against NDV in BHK-21 cells. An initial cytotoxicity assay was performed using different dilutions of E. purpurea extract to ensure that the extract chosen would not have cytopathic results on BHK-21 cells. The results of the assay showed that the extract is safe for the cells as it did not have any cytopathic results. An MTT assay will then be completed in order to determine if a 10-3 dilution of E. purpurea extract has an effect on BHK-21 cell viability when treated with various NDV dilutions. If cells treated with the extract have less cell death post viral infection compared to the cells with no extract treatment, our prediction that E. purpurea has antiviral effects on NDV can be supported. The treatment of NDV with E. purpurea can help show how the natural extract works as an antiviral.
Poster 18: The Antiviral Effects of Elderberry Extract on Newcastle Disease Virus (NDV)
Caeley Terapane, Tyler Michael, and Melissa Garcia

This study will focus on determining the antiviral activity of elderberries on the Newcastle disease virus. BHK-21 cells will be infected with Newcastle disease virus (NDV) and treated with different concentrations of elderberry extract in order to determine the antiviral effects of elderberries on NDV-infected cells. If elderberry extract can be used to treat influenza and the common cold, other viral infections such as NDV should have the same effect when introduced to elderberry. Elderberry contains compounds, such as flavonoids and anthocyanins, which are believed to have antiviral proteins. Some studies also suggest that elderberry may stimulate the immune system, which could help the body defend itself against viral infections. An MTT cytotoxicity assay will be performed with the main goals of determining what effects elderberry extract has directly on the proliferation and viability of BHK-21 cells, and determining what concentration of extract will be safe to use on these cells. Another preliminary TCID50 cytotoxicity assay will be performed to determine the concentration of NDV virus suspension required to infect half of the BHK-21 cells in the cell culture. Once the initial MTT assay and TCID50 assay have been performed, a plaque reduction assay will be conducted with the main goal of determining the antiviral effects of elderberry extract on the late-stage infection of Newcastle Disease Virus (NDV) in BHK-21 cells. We expect the results from these tests to indicate that elderberry extract when introduced to NDV-infected BHK-21 cells, will have direct antiviral properties against the spread of infection and promote the proliferation of the cells themselves.
Poster 21: The effect of Matricia chamomilla on Newcastle Disease Virus on BHK-21 cells
Jaylyn Long, Tyler Lowe, Rose McMullen

Newcastle Disease Virus (NDV) is a virus that attacks poultry’s digestive, nervous, and respiratory systems. There has been substantial research investigating vaccination and antibiotics of this virus; however, these techniques have been proven to be less useful over time. Our research project seeks to test if chamomile extract has an effect on NDV proliferation in BHK-21 cell cultures. We hypothesize that by introducing the chamomile extract, German chamomile (Matricaria chamomilla) to BHK-21 cells infected with NDV, the number of cells killed by the virus will decrease. To test the cytotoxicity of the chamomile extract on BHK-21 cells, an MTT assay will be performed. Six different dilutions of the chamomile extract, ranging from 10^-2 to 10^-8, will be tested and compared to the control: BHK-21 cells without chamomile. A second MTT assay will be performed to analyze the effectiveness of the chamomile treatment on virus proliferation. Tolerable concentrations of chamomile will be tested and compared to the control, BHK-21 and NDV, and BHK-21 cells without the virus or treatment. The viability of the treated and untreated cells will then be evaluated and compared. The cytotoxicity test revealed that all dilutions of chamomile extract are tolerated by the BHK-21 cells. We plan on performing an MTT assay using the 10^-2 dilution of chamomile and different concentrations of NDV. Using a one-way ANOVA test, we expect that the treated cells will have a higher absorbance than the untreated cells, indicating that chamomile-treated cells have a higher metabolic rate than untreated cells when infected with NDV.
Poster 25: Using Different Concentrations of Ginger Root Extract derivative to Test the Effect on Encephalomyocarditis Virus in BHK-21 cells as a Pre-treatment, Co-treatment, and Post-treatment
Lordina Agyekum, Arianna Chase, Marion Robinson

Encephalomyocarditis virus is a known livestock virus that particularly affects pig farms as well as other mammals through contaminated food and water. It is a known zoonotic disease that can infect humans and cause physiological symptoms if infected. Ginger Root has gone under recent investigation in antiviral therapy with showing abilities to attenuate viral replication pathways. Its derivative, Gingerenone A, is highly prevalent in the root and will be used in this experiment as we plan to observe it as a form of treatment for Encephalomyocarditis virus (EMCV) in baby hamster kidney (BHK-21) cells. We will test if Gingerenone A has any effect on EMCV infectivity when used during pretreatment, co-treatment, and post-treatment of the virus. We hypothesize that if given a range of different concentrations of ginger extract, the highest concentration (20 micromolar) of the Gingerenone A will decrease infectivity of EMCV in the three treatment groups. Through the measure of cell viability by MTT assay and virus infectivity of TCID50 assay, we will be able to analyze and determine the constraints that decrease cell death and increase cell viability compared to the control group of EMCV infected BHK-21 cells.
Poster 29: The Effect of the Bloodroot Alkaloid, Sanguinarine, on Newcastle Disease Virus
Ciara Donnangelo and Delaney Baratka

Sanguinarine, a natural alkaloid of bloodroot, has been shown to have antiviral potential in past studies. For this experiment, we want to test these properties using the Newcastle disease virus (NDV) to infect sanguinarine-treated BHK-21 cells. Both sanguinarine and NDV have an effect on the molecular target NF-kB signaling pathway, which controls cell viability. This leads us to believe that sanguinarine may be a probable treatment for NDV. To test this, we plan to perform an MTT assay to determine cell metabolic activity and cytotoxicity. We also plan on a cell viability assay to measure cell survival. The main purpose of this study is to gain a better understanding of the antiviral and cytotoxic properties of sanguinarine.

BIOL 445 Research Practices in Aquatic Ecology, Dr. Abbie Tomba
Students conduct original research projects focusing the ecology of local stream organisms such as aquatic invertebrates and algae. Student projects can be lab or field based and often answer questions addressing how different factors affect individuals, populations, or the biodiversity of these different groups.

The following are the projects presented in this symposium:

Poster 2: Flow rate effect on Parasitism in the Rappahannock River
Taylor Nicholson, Jenny Vuong, Kaitlin Butler, Joshua Rowe

Aquatic freshwater snails are grazers that are intermediate hosts for many parasite species like trematodes, which utilize the host’s body to their advantage, changing the host’s distribution patterns to increase parasitic transmission. This relationship is important for ecosystem dynamics and understanding where this relationship occurs most frequently. We hypothesized that low-flow areas of the Rappahannock River in Fredericksburg, Virginia have a higher prevalence of parasitism due to previous findings that there’s a higher overall snail density in pools. We chose a total of 16 1x1m areas in pool and riffle habitats of the river to collect the snails and test abiotic factors, including shade, water temperature, pH, %DO, and flow rate. We then dissected the snails, identified as Elima and Leptoxis, to determine parasite status and species. So far, we have found that neither shade (T-test, t = 1.051, df = 14, p = 0.844) nor water temperature (Two-sample Wilcoxam = 16, p = 0.052) differed significantly between the two habitat types. Of the 240 snails collected, there was an average of 0.00 ± 0.00 (n = 90) parasites found in the snails of the riffles whereas the pool snails had an average of 3.50 ± 1.09 (n = 150) parasites. Further analysis using T-tests to determine differences between pools and riffles regarding other abiotic factors and parasite and snail species will be conducted. We will also complete a linear regression to indicate the relationship between infected snail abundance and flow rate. At this time, analysis is ongoing.
Poster 10: Trematode parasite prevalence in Elimia virginica snails based on water depth
Eliana Ramirez, Rosie Stewart, Noah Smith, Anias Saunders

Freshwater snails live in shallow or deep areas of water where they can be infected by trematode parasites. Trematodes are able to live anywhere and are known for transmitting parasites to snails to be their temporary host. Parasites have the ability to manipulate a snail’s behavior and movement by moving snails closer to the water’s surface risking predation and infection. We decided to conduct an observational study to investigate the effects of trematode parasites on Elimia virginica snails in the Rappahannock River, specifically comparing the prevalence of parasites in shallow vs. deep water. We sampled 10 shallow and 10 deep pools where 10-100 snails were collected for each area. Pools were one by one meters in size and a depth of below or above 0.3 meters. Other factors were also measured for consistency such as pH, DO, temperature, and shade. Once snails were collected, they were placed into an ethanol bag and refrigerated in a lab room. During lab processing, snails were measured and recorded in width and then dissected to look for parasites. Results demonstrated that there were six infected snails in shallow pools and only three in deep, supporting our hypothesis of snails residing in shallow pools. Parasitized snails in shallow were 7.15% compared to 7.49% in deep pools. Snails that were larger in width had more parasites than smaller ones. This study could be useful for future references in behavioral patterns of E. virginica snails in freshwater habitats when infected by trematodes.
Poster 15: The Relationship Between Runoff Nitrogen and Periphyton Biodiversity in the Rappahannock River.
Alan Fletcher, Caitlin Moore, Ellie Shanahan

Researchers across the globe have sought to study the effects of large-scale agriculture on aquatic environments. This study sought to observe the relationship between varying levels of fertilizer-based nitrogen and the biodiversity of periphyton in the Rappahannock river. Periphyton refers to the cultures of microscopic producers found on a variety of aquatic surfaces. As primary producers, periphyton form a foundation on which a freshwater ecosystem rests. The researchers hypothesized that as nitrogen levels increased, so would the biodiversity of observed periphyton. This hypothesis was supported by the rationale that nitrogen, as a crucial element for autotrophic development, would have a measurable impact on periphyton proliferation if altered. To answer the question posed by the researchers, a singular monoculture of periphyton was collected from the Rappahannock river and divided into 25 samples. These sample cultures were separated into 5 groups. These groups would be exposed to one of five treatment levels. The treatment levels were 0x, 0.5x, 1.0x, 1.5x, and 2.0x the baseline nitrogen level of the Rappahannock river. After 2 weeks of exposure, the 25 periphyton samples were observed under a microscope and their taxa and number of individuals within them recorded. The researchers found that the periphyton cultures exposed to the baseline nitrogen levels displayed the greatest variety of taxa and number of individuals when compared to the other treatments. This did not support the initial hypothesis made prior to the experiment.

BIOL 472K Research in RNA Technology, Dr. Ginny Morriss
This course exposes students to the world of gene expression through the lens of RNA. We cover the biosynthesis, processing, and function of different RNA types and explore how RNA biology can be leveraged for use in research applications. Students learn basic techniques that are used in RNA laboratories throughout the world and design projects that utilize RNA technologies to study a question of interest.

The following are abstracts for the projects presented in this symposium:

Poster 5: The Relationship Between CRISPR-Cas9 Dop2R Gene Knockout and Climbing Velocity in Drosophila melanogaster
Jessie Mills, Analisa Ayala, Yamila Merida

Dopamine receptors play a role in human learning abilities, hormonal control, and locomotor function. Knockout of the human DRD2 gene is associated with diseases such as Parkinson’s, which causes mobility issues. The ortholog Dop2R plays a similar role in Drosophila melanogaster, working as a dopamine inhibitor to regulate the mobility of the fly. In our experiment, we are examining the effect of Dop2R knockout on Drosophila climbing ability. By targeting the Dop2R gene, dopamine suppression is no longer possible, and excitable neurons will continuously fire, stimulating action potentials and causing the impairment of fly climbing ability through tremors, stiffness, or in extreme cases paralysis. We completed crosses between virgin female UAS-Cas9.P2/CyO; tub-Gal5/TM6B1Tb1 and male Dop2R sgKO/Dop2R sgKO. From the F1 generation, we were able to collect UAS-Cas9.P2/+; tub-Gal4/Dop2R sgKO experimental flies and control flies. We measured climbing velocity (mm/sec) in the Dop2R KO flies compared with control groups separated by sex. ImageJ will be used to analyze climbing velocity data using a two-way ANOVA. To confirm knockout efficiency, RNA will be isolated, followed by RT-PCR and gel electrophoresis. We expect to see lower average climbing velocity for the Dop2R KO groups compared to the controls. If the Dop2R KOs have lower average climbing velocities, we can support our prediction that the knockout of Dop2R impacts climbing abilities. The knockout of the Dop2R gene can help show how motor function is affected in mobility disorders such as Parkinson’s disease.
Poster 11: Analyzing the Relationship Between Oxidative Stress Levels and SOD1 Using Drosophila Melanogaster Relating to ALS
Evelyn Buehren, Charlotte Russell

The primary objective of this research study is to analyze the relationship between oxidative stress levels and SOD1 in relation to ALS. Amyotrophic Lateral Sclerosis (ALS) is a rare neurological disease that causes motor neuron death, resulting in muscle atrophy. There is no known cure for ALS and only two therapies have been approved by the FDA. Mutations in the SOD1 gene, a regulator of oxidative stress, have been linked to ALS. We generated neuron-specific, temperature sensitive SOD1 RNAi knockdown and CRISPR/Cas9 overexpression flies to study muscle function and oxidative stress compared to wild type flies. To avoid embryonic lethality, flies were incubated through the embryonic and larval period at 25 degrees C and switched to 30 degrees C during the pupal stages for one week to activate the knockdown and overexpression. We measured climbing velocity (mm/sec) as a proxy for motor function. We will measure oxidative stress levels using a marker, the mpk2 gene. RT-qPCR will be conducted to analyze the expression of SOD1 and mpk2 in the knockdown, overexpression, and control groups. The experimental groups will be compared to a control group of wild-type Oregon R. We expect to find decreased motor function in both overexpression and knockdown groups compared to the control group because altering expression of the SOD1 gene is toxic to motor neurons. We expect the RT-qPCR to show increased oxidative stress in the experimental groups, compared to the control, indicating that SOD1 mutations are linked to ALS due to oxidative stress mechanisms.
Poster 17: MBNL1 Downregulation Affects Celf1 mRNA Decay by Alternative Splicing and Polyadenylation
Samantha Schwarting, Arshpreet Brar, Orianne Mbuyi Mujinga Kazadi,

Myotonic dystrophy type 1 (DM1) is a disease characterized by skeletal muscle weakness and myotonia. DM1 is caused by the expansion of CTG repeats in the 3’ untranslated region (UTR) of Dystrophia myotonica protein kinase (DMPK) gene. In DM1 patients, Muscleblind like 1 (MBNL1), an RNA binding protein, is sequestered at the CTG repeats while CUGBP Elav- Like Family Member 1 (CELF1), another RNA binding protein, is upregulated. MBNL1 affects alternative splicing and alternative polyadenylation in the 3’ UTR of CELF1. Given the role of MBNL1 in mRNA decay and upregulation of CELF1 proteins DM1, it is expected that MBNL1 facilitates the decay of Celf1 mRNA by promoting the formation of less stable Celf1 mRNA isoforms. We used siRNAs to knockdown Mbnl1 and we will look at Celf1 decay over time in C2C12 cells. We harvested cells at 0, 2, 4, and 6 hours after actinomycin D treatment, a drug that inhibits mRNA synthesis. After harvesting the cells, we isolated RNA, performed RT-PCR, and we will perform polyacrylamide gel electrophoresis to look at the amount of different Celf1 mRNA isoforms and the total Celf1 mRNA present at each time point. We will use ImageJ to analyze gel electrophoresis results and confirm MBNL1 knockdown using RT- qPCR. Upon the successful knockdown of MBNL1, the experimental group will show a slower decay rate of Celf1 mRNA compared to the controls. The results will help us determine if MBNL1 regulates CELF1 proteins through mRNA decay.
Poster 33: The Effect of Apc/Apc2 KO on Drosophila melanogaster Colorectal Tumor Growth
Willa Clore, Alexis Miller

The adenomatous polyposis coli (APC) gene is a tumor suppressor gene composed of the Apc-like and Apc2 genes that regulates cell growth and prevents proliferation of metastatic colorectal cancer cells. Drosophila Melanogaster is a model organism for analyzing the effects of functional changes of tumor suppressor genes because of the shared genomic and morphological similarities with the mammalian signaling pathway. To study the effects of decreased APC function, the experimental flies will undergo CRISPR/Cas9 knockout (KO), and those with the APC gene intact will be used as the control. Flies with ubiquitous Apc/Apc2 knockout, driven by alpha-tubulin 84B regulatory sequences resulted in lethality of all experimental flies. These results indicate that the Apc/Apc2 CRISPR/Cas9 KO worked effectively, as hypothesized. To address this lack of an experimental group, Apc/Apc2 sgRNA KO flies will be driven using skeletal muscle-specific myosin heavy chain regulatory sequences, and the offspring will be used as the experimental group. Both the experimental and the control groups will contain subgroups that will either consume 2mM acrylamide or 7.5% EtOH for ~3 days, or not have any carcinogen exposure. After exposure, tumor growth will be quantified using microscopy, followed by RNA isolation. The RNA will then be analyzed to study the effect the APC gene has on tumorigenesis (i.e. initation or progression) of the Drosophila m. colorectal tract. With this data, a 2-way ANOVA will be performed to determine the role of the APC gene on colorectal tumor growth in control groups compared to carcinogen-exposed groups.
Poster 36: The Effect of GlyS Over-Expression on Drosphila melanogaster Exercise Tolerance
Owen Reilly, Nathan Terrell, Peyton Garst

Generalizing alterations in skeletal musculature solely due to hemodynamic deficiencies and undermining enzymatic activity, including glycogen synthase, has led to inefficient treatment of exercise intolerance. Glycogen synthase is crucial in the anabolic pathway of glycogen deposition and is required for the maintenance of muscle’s metabolic fuel. We developed an inducible, muscle-specific Drosophila melanogaster (fruit fly) model over-expressing glycogen synthase (Glys), resembling its human ortholog, GYS1. We hypothesized when subjected to overexpression, Drosophila melanogaster will present observable increased exercise tolerance. Virgin female overexpressed Glys flies were crossed with male UAS-Cas9.VPR,tub-Gal80/Mef2R-Gal4/Tm6Bb,Tb flies. Experimental flies were isolated and are currently being incubated for one week at 30 degrees Celsius. Next, a negative geotaxis assay will be performed, testing the fly’s ability to perform adequate locomotion up seven cm during a five-second duration. Successively repeating the assay will allow for the analysis of flies’ exercise tolerance by comparing the number of flies that reach the designated mark each trial. If a steady increase in pass rate is documented then it may be inferred that overexpression of Glys is effective in increasing exercise tolerance. To confirm the data collected is a direct result of Glys overexpression RNA isolation and RT-qPCR will be conducted; thus, ensuring anticipated genomes were properly manipulated. Upon completion of this study, a more developed understanding of exercise intolerance due to alteration glycogen synthesis may be established; potentially aiding current endeavors to formulate effective treatments.

The following abstracts are projects presented at the 2023 Fall Jepson Science Center Symposium, separated by departmental affiliations:

Biological Sciences

Poster 12: The Effect of Myoglianin Knockdown on DM1 Symptoms in Drosophila Melanogaster
Charlotte Russell, Advisor: Dr. Ginny Morriss

The primary objective of this research study is to determine the relationship between myostatin and Myotonic Dystrophy type 1 (DM1). DM1 is an inherited disorder caused by the expansion of CTG repeats in the 3’ untranslated region of the DMPK gene. There is currently no known cure for DM1 and current treatments include physical and occupational therapy to manage symptoms. While DM1 causes muscle wasting, myostatin-related muscle hypertrophy is a condition that causes an increase in muscle mass. The primary function of myostatin is to prevent excessive muscle growth, therefore reduced production of myostatin can cause overgrowth of muscle tissue. Myoglianin is the myostatin ortholog in the fruit fly, Drosophila melanogaster, and was knocked down using RNA interference in this research study. We hypothesize that since myostatin-induced hypertrophy and DM1 exert opposite effects on the muscle, myoglianin depletion could potentially be used to treat myotonic dystrophy. In this study, four groups of fruit flies were compared using functional analysis to examine whether impairments in climbing and flight ability shown in DM1 flies could be rescued. First a climb assay was conducted, then a flight assay to determine if myoglianin knockdown could rescue impairments in climb and flight muscles. RT-qPCR will be used to evaluate the success of the RNAi knockdown. Because atrophy and hypertrophy typically balance each other in normal muscle, by activating a hypertrophic response in the muscle, we expect to re-balance the atrophy in the DM1 model.
Poster 14: Examining the therapeutic efficacy of chemotherapy in combination with methionine restriction in breast cancer cells.
Abigail Glenn, Advisor: Dr. Laura Sipe

Triple negative breast cancer (TNBC) is an aggressive form of breast cancer with a poor prognosis for patients. There are limited treatment options for patients with TNBC outside of chemotherapy. As such, increasing the efficacy of standard chemotherapies in the treatment of TNBC could improve patient prognosis. One such possible route is methionine restriction; cancer cells require more methionine than healthy cells due to their state of extreme growth. Previous studies suggest potential for methionine restriction synergism with Paclitaxel, a taxol chemotherapy targeting microtubules during mitosis. TNBC cells grown in methionine restricted media (3%, 12%) had markedly reduced cell viability compared to control cells. Interestingly, methionine restriction alone was more effective than Paclitaxel (5ng/mL, 10ng/mL) to reduce TNBC cell viability. However, when combined, TNBC cell viability was not reduced beyond methione restriciton alone. Additionally, TNBC cells grown in either methionine restriciton (3%) or Paclitaxel (5ng/mL) did not demonstrate an increase in apoptosis, nor did the combination treatment. Overall, the effects of methionine restriction drove an observed decrease in proliferation and cell viability without leading to apoptosis. Similarly, Paclitaxel decreased TNBC viability and proliferation, but apoptosis was not observed after 72 hours. Yet in combination, TNBC viability did not further decrease or induce apoptosis. As such, methionine restriction did not enhance the efficacy of Paclitaxel chemotherapy. Future works will aim to examine methionine restriction synergism with additional classes of chemotherapy beyond taxols, such as Cisplatin, an alkylating agent, and 5-Fluorouracil, an antimetabolite.
Poster 22: Knockdown of Pvr and its Relation to DM1 Muscle Wasting in Drosophila
Madeline Brunt, Bonnie Butler, Rose McMullen, Advisor: Dr. Ginny Morriss

Myotonic dystrophy type 1 (DM1) is an inherited multisystem disorder that causes severe muscle wasting. DM1 is the result of unstable CTG-repeat expansions in the untranslated region of the dystrophia myotonica protein kinase (DMPK) gene. Previous research using a mouse model of DM1 with severe muscle wasting showed deregulated PDGFRβ signaling. PDGFRβ is a receptor tyrosine kinase that regulates cell growth and survival. Our lab hopes to expand on this research with use of the Drosophila melanogaster model. This is because the role of the fruit fly homolog, Pvr, has not been extensively studied within muscle wasting. Using the Gal4/UAS system in Drosophila melanogaster, we can express expanded CUG-repeat RNA in transgenic lines to determine how Pvr plays a part in DM1. The goal of this project is to modulate expression of Pvr by knocking it down and its downstream components to determine whether Pvr signaling is required for proper skeletal muscle development and function in DM1.
Poster 26: Cytotoxicity of Phage Jabberwock and Phage Atlee Proteins
Tyler Downs, Eleni Kepler, Raesa Zia, Advisor: Dr. Swati Agrawal

This project focuses on the characterization of previously isolated Bacillus phages Atlee and Jabberwock to determine their therapeutic potential against antibiotic resistant bacteria from the Bacillus genus. While bioinformatics prediction tools provide some insight into genes encoded by the genome, the majority of functions are unknown. These phages were isolated at the University of Mary Washington as a part of SEA PHAGES course using the non-pathogenic B. thuringiensis species; however, these phages showed a broad host range infecting other species in the Bacillus genus, including the pathogenic bacteria B. anthracis, which causes anthrax, and B. cereus, a gastrointestinal pathogen. A better understanding of proteins encoded in the genomes of Bacillus phages will aid in the process of combatting such bacteria. For each phage’s genes, a subset of protein will be selected for experimental verification of the gene model and analysis of cytotoxicity function. The main steps in the characterization process include amplification, cloning of genes, and expression of the protein in an appropriate expression vector. In addition, an assay analyzing toxicity of the phages to determine their effectiveness against bacteria will be completed. So far, 9 genes have been successfully amplified and cloned into a TOPO vector backbone. Following sequence verification, they will subsequently be cloned into protein expression vectors for verification of gene model and bacillus expression vectors for analysis of cytotoxicity and immune suppressor function.
Poster 28: The role of the Pvr signaling pathway in Drosophila muscle phenotypes
Delaney Baratka, Advisor: Dr. Ginny Morriss

Myotonic Dystrophy Type One, DM1, is a progressive, multisystemic, and autosomal dominant disorder caused by expansion of CTG-repeats in the 3′-UTR of the DMPK gene. While we understand the causal mutation that leads to DM1, the underlying mechanisms of disease progression remain unclear. Prior research in a mouse model of DM1 identified deregulated PDGFR- β signaling. PDGFR-β plays a role in cell survival and differentiation. Another study implicated the ligand for Pvr, the Drosophila ortholog of PDGFR-β, as a modifier of DM1 phenotypes. This study will evaluate the role of the Pvr signaling pathway in Drosophila muscle phenotypes, helping us better understand its role. We plan to modulate the expression of pvr by RNAi knockdown (pvr-RNAi) in flies lacking the DM1 CUG repeats and by overexpression of Pvr (Pvr-OE) flies with and without the CUG-repeat expression (CUGexp). The Drosophila DM1 model uses the Gal4/UAS system to express the expanded CUG repeats. The use of the fruit fly model allows us to study the signaling pathway in a more simplified view to understand its role in normal muscle functions. Our main goal is to determine the role of Pvr signaling for proper skeletal muscle structure and function. A secondary goal is to determine whether overexpression of Pvr in flies affected by DM1 can rescue the DM1 muscle phenotype.
Poster 31: In planta gene expression by the fungal endophyte Beauveria bassiana in Glycine max
Harrison Miles, Advisor: Dr. Dianne Baker

Endophytic fungi grow within plants without causing the plant harm. Beauveria bassiana, an endophytic fungus, is also an entomopathogen, causing disease in insects; this property makes it useful as an organic pesticide. Beauveria kills insects by producing toxic compounds, two of which are called bassianolide and beauvericin. Previous studies have quantified how much of these compounds are produced during the insect infection, but less is known about how much they are produced within the host plant. Understanding this fungal gene expression could inform the timing and efficacy of its use as a biological control. This experiment attempted to inoculate soybean (Glycine max) with Beauveria bassiana to measure the endophyte’s production of the toxic compounds beauvericin and bassianolide. However, neither culturing inoculated plant tissue nor analysis of gene transcripts showed evidence of inoculation success. These results are not uncommon as retrieval of experimentally-established endophytes varies in the literature and may be low. Cultivar-specificity may play a role in inoculation success. Further optimization of experimental methods is needed.
Poster 38: An Inquiry into the Validity of the Tube Test as a Measure of Dominance in Mice
Tim Philbeck, Advisor: Dr. Parrish Waters

The social interactions of mice can provide valuable information on their behavioral and physiological state. The Tube Test is a practical and inexpensive method that is commonly used to estimate the social rank of mice living in social cages, but this test is not universally accepted as a reliable and objective measure of social dominance. Therefore, we designed a study to assess the validity of this test, which will enhance our ability to determine social relationships among mice in our lab. We kept two strains of mice (outbred CD-1 and inbred C-57) in strain specific dyads and performed multiple iterations of the Tube Test over 29 days. We compared
these results to home cage aggression, hormone levels, and anatomical features that are associated with social dominance in mice (albeit using more expensive and labor-intensive methods than the Tube Test). Performance in the Tube Test did not predict plasma hormone
levels or preputial gland size. We observed a relationship between Tube Test performance and home cage aggression, in which mice that consistently lost the Tube Test exhibited higher levels of aggressive attacks toward their cagemates (p ≤ 0.05). Our results suggest that care should be
taken when assigning social ranks to mice based on results from the Tube Test.
Poster 41: A Pilot Study on the Impact of Riparian Restoration Along the Rappahannock River in Belle Isle State Park on Wildlife Biodiversity.
Caroline Pitches, Kylie Jackson, Mary Coy Woodrum, Advisor: Dr. Andrew Dolby

Riparian zones are areas along the edge of a river or stream. They provide many ecosystem services including maintaining water quality, soil health, and plant and animal diversity. Riparian zones are extremely vulnerable to change. The surrounding land and biodiversity can face severe decline if it is damaged. Restoration projects and follow-up studies on these ecosystems are rare. One riparian restoration project was conducted along a rapidly eroding shoreline along the Rappahannock River in Belle Isle State Park in 2017. Our study aimed to analyze the success of this project by evaluating the biodiversity that now utilizes the restored wetlands and beaches. We hypothesized that the restored shorelines in Belle Isle State Park made a significant impact on wildlife species richness and abundance in comparison to unrestored shorelines, and we predicted that both species richness and abundance would be greater in restored regions than in unrestored regions. We installed six wildlife cameras, three along restored and three along unrestored shorelines, to observe wildlife over the course of seven weeks. We found insignificant results for species richness being 8 species for both site types and an insignificant p-value of 0.249 for species abundance between site types. Although our study did not produce significant data, it did provide useful insight on how this study could be improved and be extended further in future studies on how biodiversity is impacted by riparian restoration in Belle Isle State Park.
Poster 42: Long Range PCR for Generation of Fluorescent in situ Hybridization (FISH) Probes
Delaney Humphrey, Advisor: Dr. Ginny Morriss

Myotonic Dystrophy Type 1 (DM1) is characterized by an expansion of CTG repeats in the DMPK gene and can cause muscle weakening and wasting. The transgenic flies in this study have either 60, 250, or 480 human CTG repeats which cause DM1. This project aimed to generate fluorescent in situ hybridization (FISH) probes to confirm previous research that genetically localized the (CTG)60, (CTG)250, and i(CTG)480 transgenes in the Drosophila genome. FISH can be used to determine the location of specific DNA sequences within the genome, allowing researchers to more rationally design crosses which can be used for genetic modulation of DM1. FISH uses fluorescently labeled probes that hybridize to the CTG transgene, as well as four unique chromosomes in the fly. To generate the probes, long-range PCR was used to amplify fragments of isolated DNA. The products of the long-range PCR are visualized on agarose gels. To troubleshoot the PCR, as some targets have not yet yielded bands and some are giving nonspecific bands, primer tiling will occur. Primer tiling will enhance the reliability, accuracy, and coverage of amplification in the DNA sequence. PCR fragments will eventually be purified from the gel and fluorescently labeled using nick-translation. The fluorescent probes will be used to label chromosomes prepared from Drosophila larvae using fluorescent in situ hybridization.
Poster 43: The Effect of Social Isolation on Orexin Production and Hedonic Drive in Female Mice
Hudson McNerney, Advisor: Dr. Parrish Waters

Social stress is a primary instigator of psychological disorders in humans. While social stress results from social dominance relationship (i.e., being subordinate), social isolation is an intense psychosocial stressor for social organisms (including mice and humans) that can have profound effects on physiological and neurobiological systems. One of these negative effects is a loss of feelings of reward, or anhedonia. Rewarding feeling in response to positive stimuli, or ‘hedonic drive’, is controlled in largely orexins. Two neuropeptides, orexin A and orexin B, are produced in the lateral hypothalamus, and can be disturbed by intense or chronic stress. While the effects of these ligands on reward seeking are understood, how isolation stress can affect orexins, and how this may influence a depressed state has not been thoroughly explored. This project will examine the effects of isolation stress on central orexin systems and anhedonia, as a model depression in female mice. We will keep mice in social or isolated cages. Each cage will contain a raised platform with a sucrose pellet dispenser to test motivation (i.e. hedonic drive), as well as running wheels. We will track which animal is running using RFID tags to track each individual’s activity. After 4 weeks in this environment, we will test all mice in discrete behavioral tests that assess hedonic drive and anxiety. We will collect brain and blood tissue to assess orexin and corticosterone, respectively. Our findings will contribute to a better understanding of the role that orexins play in regulating stress responsive physiological systems.
Poster 44: Assessing progression of muscle phenotypes in an adult-onset model of myotonic dystrophy in Drosophila melanogaster
Ashlyn Rauch, Kayla Rodriguez, Sarah White, Advisor: Dr. Ginny Morriss

Myotonic Dystrophy Type One (DM1) is a multisystemic disorder caused by expansion of CTG repeats in the dystrophia myotonica protein kinase (DMPK) gene. Individuals diagnosed with DM1 may display a wide spectrum of CTG expansions, ranging from 50 to 4000 repeats. Unaffected individuals typically have between 5 to 37 CTG repeats. In individuals with shorter repeat expansions, development of symptoms typically occurs in the later adult years, whereas individuals with very long expansions can have a juvenile or congenital onset. Since DM1 results in progressive worsening of symptoms over generations, it is important to understand the progression of the disease. The Drosophila DM1 model uses the GAL4/UAS system to drive expression of expanded CUG repeat-containing RNA (CUGexp). This study uses the 1151-Gal4 driver, an adult-onset, skeletal muscle-specific driver to study the progression of skeletal muscle weakening and wasting. We crossed the 1151-Gal4 lines with transgenic lines containing 60 (UAS-CTG60) and 250 (UAS-CTG250) CUG repeats to represent the unaffected and DM1 mutant phenotypes. We are in the process of testing 1151-Gal4>UAS-CUGexp flies for physiological defects at 3, 4, and 5 weeks of CUGexp expression. We use tests that measure climbing velocity and flight ability in the flies to assess defects in physiological function in the flies as well as histological analysis to assess muscle atrophy. This study determines the time of onset of the DM1 muscle phenotypes for Drosophila DM1 model.

Earth and Environmental Sciences

Poster 4: Examination of the Potential Health and Ecological Impacts of the Total and Bioavailable Concentrations of Harmful Metals in Some Kingston, Jamaica, Surface Soils
Anna Velardi, Faith Jones, Audrey Turner, Advisor: Dr. Melanie Szulczewski

This study investigated background levels of concerning metals in a variety of soils in and near Kingston, the capital of Jamaica. Minimal soil sample collection and analysis had occurred since a 1988 island-wide geochemical survey revealed very high concentrations of total Cd in many regions, along with elevated concentrations of As, Cu, Zn, and Cr in some types of soil, with background lead levels elevated only at specific polluted sites. An updated examination was deemed important due to a growing city population, increased fuel combustion, and intensive urban gardening. This study analyzed soils collected in 2022 for total metal concentrations, as well as bioavailable concentrations, previously only reported for lead. The typically basic soils in this urban center of a tropical country provided interesting preliminary results regarding metal content in the region’s soils. Arsenic and cadmium were detected in every soil, usually far exceeding US EPA cleanup levels. By contrast, Pb levels were lower than expected. Further analysis looked for correlations in the soil samples between metal concentrations and pH, organic matter content, soil texture, and biologic activity, with concerning results.
Poster 23: Evaluating Sedimentary Trace Metal Contamination, Bioaccumulation, and Fish Species Diversity Near A Virginia Coal Ash Repository
Summer Orledge, Advisors: Dr. Ben Kisila and Dr. Tyler Frankel

This research assesses the spatio-temporal distribution and biological impacts of trace metal pollutants near Bremo Power Station. This decommissioned coal-fired power plant, located by the James River in Virginia, stores 6.2 million cubic yards of coal combustion residuals (CCRs) in its adjacent North Ash Pond. It is one of hundreds of CCR repositories in the U.S. Industrial coal combustion and subsequent waste disposal release toxic, persistent, and non-biodegradable trace metals into the environment. CCRs can infiltrate waterways via accidental spills, authorized discharge, or leaching from insufficiently lined impoundments. The latter remains under-examined, as existing research primarily focuses on large spills. Surficial sediments, sediment cores, and native adult panhandle pebblesnails (Somatogyrus virginicus) were sampled from the James River upstream, downstream, and adjacent to the station. Samples were analyzed for 13 CCR-associated trace elements (Al, As, B, Cd, Ca, Cr, Cu, Fe, Pb, Mg, Mn, Se, and Zn) using ICP-OES (inductively coupled plasma optical emission spectrometry.) In addition, eDNA (environmental DNA) samples were collected and fish species diversity analyzed using MiFish primers. Preliminary results indicate significantly enriched Al, Cu, and Pb in surficial sediments downstream from the station. We anticipate increased concentrations of trace metals in snails sampled downstream, accompanied by diminished fish diversity. Expected findings also include a temporal correlation between the plant’s operational period and trace metal enrichment. Further results will provide crucial insight into the transport, deposition, and lasting ramifications of CCR-associated trace metals, informing environmental remediation efforts and illuminating risks to ecosystem and human health.
Poster 34: Evaluating the Geochemistry from Coral Species Hydnophora Microconos as a Reliable Proxy for Tropical Pacific Climate
Jessica Oberlies, Ainsley Lord, Sophia Austin, Advisor: Dr. Pamela Grothe

The tropical Pacific is a critical region for studying the impacts of climate change because of its central role in modulating global climate variability. This is most evident during extreme El Niño Southern Oscillation events, which cause large swings in global precipitation patterns. However, the lack of recorded instrumental data prior to the mid-20th century presents a challenge to quantify the extent of anthropogenic influence on tropical climate, preventing robust simulations of future climate impacts. Geochemical records from modern and fossil coral Porites are a reliable method to extend the instrumental sea surface temperature records through the preindustrial period. However, relying on one coral genus prohibits a robust reconstruction due to limited temporal sample availability spanning centuries to millennia. Here, we test a new species of coral, Hydnophora microconos, as a reliable archive to reconstruct sea surface temperature in the central tropical Pacific. As corals secrete their aragonite skeletal material (CaCO3), they preserve the environmental conditions through incorporation of both oxygen isotopes (𝛿18O) and changes in their strontium (Sr) and calcium (Ca) ratios. Coral Sr/Ca ratios record sea surface temperature (SST), while coral 𝛿18O are influenced by both SST and sea surface salinity. Initial results from a modern paired record of 𝛿18O and Sr/Ca from a Hydnophora microconos coral from Kiritimati Island show that these corals reproduce the instrumental SST and track warming from recent El Niño events, suggesting these corals may be reliable proxies for paleoclimate reconstruction. Future work includes comparing young fossil Hydnophora microconos geochemical records with the well-established Porites geochemical records from Kiritimati Island to ensure the fossils reproduce the established Porites-based SST record for this island. If successful, Hydnophora microconos will be paired with Porites to create a record of the climate in the tropical Pacific for the past 200 years to quantify the timing and magnitude of warming and freshening in the tropical Pacific.

Chemistry and Physics

Poster 7: Observation and Interpretation of Exoplanetary Light Curves
Carter Bussey, Advisor: Dr. Matthew Fleenor

Space exploration and the possibility of alien life have captured the human imagination for decades. Current technology has led to thousands of extrasolar worlds being discovered, catalogued, and insight into their atmospheres. Trial observations of two Jupiter-sized planets were sent to a browser-based telescope system to better understand transit timing and observational frequency. Light curves were constructed using two Python programs and data from NASA’s Transiting Exoplanet Survey Satellite (TESS). Light curves generated from the observations showed that the reference and planet-hosting stars changed in tandem, demonstrating that the effects of atmospheric blurring are greater than the change in light due to a transit. Future work includes using the same techniques to observe eclipsing binaries with Skynet and confirming planetary candidates with TESS data.
Poster 8: Rotational dynamics of nitromethane using the random phase quantum state model
Katherine Lauderbaugh, Advisor: Dr. Varun Makhija

Nitromethane is the smallest nitro-organic compound and a homemade explosive. In order to understand and control the explosion, we need to understand how the molecule reacts when it is ionized, since shock-ionization is the first step of the explosion reaction. Specifically, if we can understand how the ionization of nitro-organic compounds depends on their orientation, then we can potentially control the likelihood of ionization by controlling the orientation using laser pulses. To compute the rotational motion of nitromethane, we started by processing numerically solved the Time Dependent Schrodinger equation (TDSE), which is the central equation needed for quantum mechanics, in a C++ code, treating nitromethane as a simple quantum top interacting with a femtosecond (10-15 sec) laser pulse, which initiates rotation. We computed the rotational motion at low temperatures around 1 Kelvin up to a higher temperature of 30 Kelvin. We modeled the temperature by considering a thermal distribution of initial quantum states, each of which were propagated through the TDSE code. There were 5,180 times that the code needed to run at 30 Kelvin, which took two weeks. We estimated that at 300 Kelvin (room temperature), the code would need to run 131,209 times to calculate the entirety of the rotational motion, which would take around a year, if we ran the code in its current form. So, I am now trying to utilize the “random phase wave function” method, which has been used previously for computing the rotational motion of small molecules like sulfur dioxide at room temperature.
Poster 30: Fluid Dynamic and Water Flume Design
Boone Fleenor, Advisors: Dr. Joe Nicholas, Dr. Matthew Fleenor

Dimensionless numbers are used in fluid mechanics as a means of scaling for the purposes of design and testing. We explored the use of dimensionless numbers as they relate to the construction of a water flume that exhibits both tranquil and turbulent flow. The Reynolds (Re) and Froude numbers are both dependent upon the entry velocity and flume geometry, which we manipulated to exhibit different flow types and their associated values. Preliminary testing was completed to ensure construction specifications that provide laminar flow. Entry velocities need to be constrained to < 1.0 cm/s to maintain an Re < 1000 for the specifications. A variety of sluice gate designs were introduced to manipulate fluid depth, which has an inverse relationship with Re. For the current dynamic and geometric constraints, an average operating fluid depth must be > 4.0 cm to produce an acceptable Re.
Poster 39: Acceleration of gravity on a flat Earth
Daniel Paluh, Advisor: Dr. Desmond Villalba

In science, we learn that the Earth is a sphere and the average acceleration of gravity for Earth is g=9.81 m/s/s, but where does this acceleration of gravity value come from and how does the value change as Earth changes shape? For example, if the Earth were a flat-like shape, we expect the acceleration of gravity to vary wildly from its average value of 9.81 m/s/s. We have calculated numerically the acceleration of gravity if the Earth were a 1-dimensional line and a 2-dimensional sheet, and in both cases the value of g changed drastically at the edges compared to at the center. In our ongoing research we anticipate that in the case of other flat Earth-like shapes a drastic change in g will manifest in the 3-dimensional shapes we are studying.
Poster 40: Molecular Dynamics in Jahn Teller Distortion
Mason Clark, Advisor: Dr. Varun Makhija

Jahn Teller Distortion can cause symmetric molecules to change their structure. Under specific electronic configurations, the structure is unstable, resulting in a symmetry-breaking distortion. Our colleagues, Dr. Max Waters and Dr. Hans Wörner at ETH Zürich, might have observed this phenomenon in carbon tetrachloride experimentally, but we don’t know for sure. Using a quantum model of this system, I am working to determine how the wave-like nature (coherences) of electrons affects this geometric distortion. Successful replication of experimental results could verify both its observation and whether coherences result in Jahn Teller Distortion. Additional work will be needed to input relevant information from the original experiment and potentially replicate the results.

Music

Poster 19: Guitar Effects Synthesizer
Samuel Slate, Advisor: Prof. Rebecca Callaway

The main purpose of this study was to construct a guitar synthesizer effects pedal. The guitar synthesizer pedal is a digital signal processor that can modify analog audio in various ways by using different electronic components. Over the course of the semester, I wanted to learn how to build an effects pedal and how the components interact with each other to achieve certain sounds. At its essence, an effects pedal of this caliber is a circuit that inputs an audio signal and alters its properties to achieve different sounds. Through-hole electronic components were soldered into a pre-designed printed circuit board. The locations of the components on the PCB were meticulously located and verified, and each region on the board was researched to understand its purpose and individual effect on the audio signal. This multi-functional synth pedal works in tandem with electric guitars and amplifiers with the potential of incorporating other electronic instruments.
Poster 37: Electric Guitar Design
Gabriel Morris, Advisor: Prof. Rebecca Callaway

The main purpose of this project was to construct an electric guitar. Electric
guitars are a type of guitar that uses electricity to amplify the sound and produce different tones. The process of putting this electric guitar together involved sanding the guitar until it reaches a desired smoothness, followed by applying a waterbased sanding sealant to seal the wood. The guitar was then painted, followed by the application of a high-gloss finish. The pieces of the guitar, including the electrical circuit, neck, body, tuning pegs, the bridge, and the strings were then all assembled. This project provided a better understanding of how electric instruments are made and how they function. It also provided a unique experience into the design and eventual
construction of guitars and how the mechanical vibrations of strings can interact with the electromagnetic pick-ups to produce a electrical signal that can be processed back into sound.

2022 Fall Research Symposium

Course-directed Research

The following are descriptions of courses and research projects that were presented at the 2022 Jepson Science Center Research Symposium.

The following are the projects presented in this symposium:

Poster 1: Does a fishes’ physiological temperature preference predict its population change in response to warm and cold years?
Tiffany Skrabenek
Poster 3: Impact of sampling method on the size ranges of fishes captured
Natalie Brennan, MC Woodrum
Poster 5: Habitat type influences diet specificity in an ant
Georgia Bowling, Mackenzie Dickson
Poster 7: When the humans are away, the fish will play? Evaluating the impact of COVID restrictions on stream fish populations
Caitlin Moore
Poster 9: Variation in stream depth promotes diversity of stream fishes
Anna Czernia
Poster 11: Does the presence of a predator reduce the diversity of prey taxa among soil invertebrates?
Hunter Jones, Natalie Loeffler
Poster 13: Impact of human land use on Opossum activity levels
Tamara Garrett
Poster 15: Testing the impact of microhabitat complexity on the diversity of ant species
Ella Peck
Poster 17: Role of body size in determining the food preferences among ant species
Aziza Alikhail, Tessa Lanzafame
Poster 19: Seasonal variation in the diurnal cycle of Gray Squirrels
Mina Murad
Poster 21: The availability of open-water habitat predicts the diet composition of American Alligators
Ellie Shanahan
Poster 22: How does the abundance of a native minnow correlate (or not) with that of a recently introduced species?
Erik Dale, Priya Patel
Poster 23: A comparison of the flight altitude and velocity of Black Vultures and Turkey Vultures
Eren Edwards, Faith Fraley

The following are abstracts for the projects presented in this symposium:

Poster 2: The effects of epigallocatechin-3-gallate (EGCG) in preventing infection of BHK-21 cells with Newcastle disease virus
Carly Gorham, Amberleigh Morris, Jordan Grinkewitz

Epigallocatechin-3-gallate (EGCG) is a green tea catechin that displays evidence for inhibiting viral attachment. EGCG has shown antiviral activities against both RNA and DNA viruses such as HCV, IAV, HIV, HSV, and HBV (Calland et al., 2012). The purpose of this research was to determine the extent to which EGCG could prevent Newcastle Disease Virus (NDV) attachment to baby hampster kidney cells (BHK-21) under varying time points including when introduced 1 hour prior to infection, at the same time of infection, and 1 hour post infection. If EGCG has antiviral capabilities, it will prevent NDV attachment to BHK-21 cells. To determine EGCG cytoxicity on BHK-21 cells, an MTT assay was performed. A plaque assay was performed in order to determine the antiviral effects of EGCG. When counting plaques, there were minimal absolute plaques able to be determined for all 3 trials and treatment groups. Due to the lack of staining present in most wells after performing the plaque assays, it is likely the viability of the BHK-21 cells was low which resulted in a poor rate of NDV infection. The agarose did not detach from the wells with ease, having likely disturbed the cells, which could have contributed to the low infection rate as well. Further testing is required to determine the capability of EGCG to prevent NDV infection of BHK-21 cells.
Poster 6: The Anti-Cancer Effects of Newcastle Disease Virus on HeLa Cells
Cidney Collins and Courtney Smith

We plan to investigate the area of cancer treatment and the use of viruses to suppress such cancer cells. If cancerous cells (HeLa) are infected with Newcastle disease virus (NDV), then NDV will selectively lyse HeLa cells and can induce apoptosis. NDV is recognized in clinical settings as an oncolytic virus because it selectively replicates in cancer cells and kills them. Death receptors and mitochondrial apoptotic pathways are triggered by NDV, so we believe the virus will have the same effect in HeLa cells. If NDV can selectively kill apoptosis-resistant (cancer) cells, NDV might be a promising cancer treatment. We plan to test our research question using similar strategies of previous studies by using an MTT assay to measure cellular metabolic activity as an indicator of cell viability, proliferation, and cytotoxicity.
Poster 10: Effects of Hydroxychloroquine on Autophagy Inhibition in Encephalomyocarditis Virus Infected Cells
Eliza Van Essendelft, Ryan Meek, Emily Sizemore

The focus of this project is to evaluate the effects of hydroxychloroquine (HCQ) on Encephalomyocarditis virus (EMCV) virulence. EMCV is a virus that infects a broad range of mammalian hosts and poses a potential threat to not only public health, but also the food industry, as domestic pigs are very vulnerable to this virus. EMCV has been found to induce autophagy in infected cells, and it was also discovered that autophagy was necessary for EMCV replication. Autophagy is a necessary cellular process that functions to recycle old proteins and organelles inside a cell by segregating them and allowing them to be broken down by lysosomes. This process is what we will be trying to inhibit with HCQ as a potential treatment of EMCV infection. HCQ, a drug currently utilized to treat malarial infections, is a lysosomal acidification inhibitor that has been shown to inhibit autophagy in cancer cells, but its application to viral infections is limited. Treatment of viral infection with HCQ will be quantified by plaque assay and inhibition of autophagy will be analyzed using transmission electron microscope (TEM). TEM will show presence of autophagosomes in HCQ treated and untreated cells and allow for visualization of inhibition.
Poster 14: Antiviral Effects of RGE on EMCV
Jessica Mimms, Mary Williams

Red ginseng extract (RGE) has been explored for anti-inflammatory, antiviral, and antioxidant properties against an array of viruses. In a study done where RGE was tested against respiratory syncytial virus (RSV), researchers found that RGE treatment inhibited RSV-induced cytopathogenic formation and replication in vitro (5). Based on these findings, we explored the effectiveness of RGE on the infectivity of encephalomyocarditis virus (EMCV) with the use of in vitro cell cultures of BHK-21 cells. We hypothesized that the cells pretreated with higher concentrations of RGE will possess antiviral effects and higher cell viability. We began testing this by growing and splitting BHK-21 cells in a 1:10 split. The dilutions used for RGE were 10-1,10-2, 10-3, and 10-4. The RGE dilutions and BHK-21 cells were then added to a 12-well plate and examined once confluent to ensure that RGE allowed for cell growth. The best dilutions that allowed for cell growth were 10-2, 10-3, and 10-4, which were then used in a MTT assay. The cells were pretreated with RGE dilutions and placed in a 96-well plate. Once cell viability was confirmed, diluted EMCV was added to the control wells and the remaining columns. The dilutions of EMCV used in each of the rows were 10-3 to 10-9. The plate was then interpreted by a spectrometer. The results indicated that the control wells, without RGE, had the highest metabolic activity. This indicates that there could be possible harmful effects of RGE towards the cells. We conclude that further research of the antiviral effects of RGE is required.
Poster 18: The Effect of Garlic, Onion, and Mushroom Extract on NDV in BHK-21 Cells Cytopathic
Asifa Mossavi, Kristine Dadufalza, Christina Phillips

Newcastle disease virus (NDV) is one of the most prominently damaging diseases for the poultry industry. There is a risk of contracting this disease for all birds. Vaccines are being used to prevent Newcastle disease. However, the effectiveness of the vaccine has been limited. In addition, the vaccine is only used for the prevention of the disease, not for treatment. Hence, this research focuses on the antiviral effects of garlic, onion, and mushroom extracts because they possess the qualities of preventing viral infection. The three chosen natural sources (onion, garlic, and shiitake mushroom) contain a wide range of bioactive compounds. These bioactive compounds allow for their antibiotic, anticancer, antioxidant, anti-inflammatory, and antiviral activities. In this procedure, a monolayer of BHK-21 cells was set up with 96-well plates and incubated. After a few days, garlic, onion, and shiitake mushroom extracts as well as NDV were added to the 96-well plates and its antiviral effect was determined by performing an MTT assay to detect its absorptive effect. The results from the absorptive assay showed that the onion and garlic extracts were the most effective since they led to a high cell viability. More testing will be done to support or reject these results.
Poster 20: Effects of Bleach Derivative ClO2 on EMCV-infected BHK-21 Cells
Erin Kenealy, Caroline Joyce, Zabdi Cayetano

Encephalomyocarditis virus (EMCV) is a positive sense, single-stranded non-enveloped RNA virus with a natural reservoir in rodent populations. This zoonotic virus is spread to domestic swine populations which causes widespread damage to industry. EMCV along with many viruses are known to spread through contaminated water sources. The treatment of potable water and wastewater often uses chemicals such as chlorine and chlorine dioxide (ClO2). which inactivate viruses in a variety of manners. In 2020, during the ongoing COVID-19 pandemic, ClO2 gained legal protection as elective treatment for viral infections of SARS-CoV-2. In this study, we sought to add evidence to the current medical understanding that the consumption or intravenous administration of bleach derivatives is harmful to cellular health and not beneficial to patients with viral infections. For this study we used Clidox-S, a chlorine dioxide based sterilant, on BHK-21 cells infected with EMCV to study the cytopathic effects of EMCV and our bleach derivative. MTT assays were run on multiple 96-well plates to assess appropriate concentrations of EMCV and ClO2 before ClO2 was added in combination with EMCV. Our results, gathered by MTT and TCID50, revealed that cells infected with EMCV and treated with ClO2 displayed more cytopathic effects than cells infected with EMCV alone. These results may indicate that the consumption or administration of bleach or bleach derivatives is actively harmful to virally infected cells and should not be a candidate for treatment, preventative, or therapy in a medical setting.

BIOL 472F Plant and Animal Interactions, Dr. Josephine Antwi
The course is designed to explore the fundamental concepts of the interactions between plants and animals, with specific focus on insects and plants. Students design various studies involving insect pollinators and the effect that urbanization hason pollinators. The primary objective of the course is to teach students the basics of experimental design and executing a research project through problem solving, critical thinking, and analyzing primary literature.

The following are abstracts for the projects presented in this symposium:

Poster 4: The Effects of Shaded Habitats on Pollinator Species Richness and Diversity
Mackenzie Dickson, Georgia Bowling, Crimson Farina, and Natalie Brennan

This research aimed to observe pollinator diversity in varying light habitats by comparing two sites on the campus of the University of Mary Washington, one shaded and one non shaded. It is important to understand the ideal conditions for pollinator success in urbanized landscapes. Our field study consisted of sweeping 2 sites, during night and day, twice a week, for 8 weeks. One site was non shaded, receiving more sunlight, and contained mostly tall grasses, while the shaded site consisted of more trees and bushes. The specific goal of the study was to compare insect pollinator diversity among the two varying habitats to determine which set of conditions elicited higher species abundance and richness. Over twice as many pollinators were collected from the non shaded site than the shaded site. More pollinators were collected at night than daytime. Species diversity was higher in non shaded than shaded (Shannon-Weiner diversity index of 2.669 and 2.218, respectively) as night time with a diversity index of 2.69 (vs. 2.63 during the day). These differences were statistically not significant. The Jaccard Similarity index indicate that only 33% of species were shared between shaded and non shaded sites. Our study implies that there may be differences in species abundance and richness among habitats receiving varying levels of light. More data is needed from these sites in order to fully understand the effects of shading pollinator richness and diversity.
Poster 8: Butterfly Visitation on Four Autumn Flowering Plants
Danielle Cross, Krystal Lightell, Julenny Marte, Samantha Schwarting

The purpose of this study was to identify Lepidoptera foraging behaviors regarding the attractiveness of specific petal colors. This study aimed to use petal color to determine which common autumn flowering plants can be used to increase pollination by lepidopterans in urban gardens. Lepidoptera visits were recorded on four autumn flowering plants (Conoclinium colestinum, Anemone hupehensis, Symphyotrichum novae-angliae, and Helianthus angustifolius) at Kenmore Gardens located in Fredericksburg, Virginia. Both butterflies and plants were identified in the field using internet sources and field guides. A patch of each species of flowering plant was observed twice a week for one hour over five weeks. A total of 68 lepidopteran visits were recorded and identified down to the family level. 75.0% of lepidopteran visits were recorded on C. colestinum. The only three lepidopteran families observed were Danaidae, Hesperiidae, and Lycaenidae where 91.2% of visits were made by Hesperiidae. The lack of data prevented us from performing statistical tests and therefore, we could not conclude about how petal color affects lepidopteran visitation.
Poster 12: Determining Hymenoptera Diversity in Managed and Unmanaged Urban Landscapes
Aziza Alikhail, Curtis Kasiski, Audrianna Shepherd, Elizabeth Golden

In this study, we looked at the effect of managed landscapes on the diversity and abundance of insects in the order Hymenoptera. Today, humans are spreading out causing the mass destruction of the natural land, also known as urbanization. Urbanization has led to managed landscapes with aesthetic plants, which may not necessarily be beneficial to pollinators. In this, we collected insects from a managed and an unmanaged area at University of Mary Washington, Fredericksburg campus for two weeks. The managed area was a pollinator garden picked based on the number of plants in season and a no-mow zone was picked for the unmanaged land. Insects were identified to species level. We identified 15 Hymenoptera species at both sites with 6 species at the managed site and 8 species at the unmanaged site. This difference was not statistically significant (Chi-Square=10.33, 9 d.f., p=0.324). Species diversity was higher at the unmanaged than the managed area (Shannon-Weiner indices of 1.86 and 1.59, respectively). This slight difference in diversity could be the result of the higher plant diversity at the unmanaged area supporting more insect species. Given only one site per landscape type was sampled in this study, we would need to sample more sites the understand the effect of land management in urbanized areas on pollinators.
Poster 16: Impact of Urbanization on Moth Abundance and Diversity
Tessa Lanzafame, Cole Fincher, Angel Ramirez, Ibert Fancher

Urbanization changes the structure of natural habitats, affecting biodiversity. Moths play critical roles in ecosystems, such as pollinating plants and being prey for other animals. Urbanization often decreases moth numbers due to habitat reduction. However, light pollution is a strong attractant that can draw moths to urban areas, which can then impact their fitness. To aid moth conservation, we examined the impact of urbanization on moth abundance and diversity in urban and semi-urban areas. We collected moths from two urban areas in downtown Fredericksburg (Hurkamp Park and Kenmore Park) and two semi-urban areas on the UMW campus (behind the HCC and near the Eagle’s Nest), setting up a light trap consisting of a mercury vapor bulb pointed at a white sheet to attract moths. We sampled from one urban and one semi-urban site at night each week for six weeks, collecting moths and then identifying them to the family level. We found that the mean abundance of moths collected from the urban sites (1.33 ± 0.82) was lower than that of the semi-urban sites (2 ± 1.83). The urban sites were more diverse, as their combined Shannon-Wiener Diversity Index value was 1.21 compared to the semi-urban sites’ value of 0.76. However, calculating the Jaccard Coefficient of Community Similarity showed that the urban and semi-urban communities were similar in moth family composition (CCJ=0.75). Our results suggest that light pollution may not attract moths as strongly as predicted and that urbanization level does not seem to greatly influence moth diversity

Independent Projects

The following abstracts are projects presented at this symposium, separated by departmental affiliations:

Biological Sciences

Poster 24: The COVID-19 Pandemic: How Has The Pandemic Affected Chronic Disease Care and Follow-Up
Author: Hope Grzebien; Research Advisor: Mr. Michael Stebar

COVID-19 first emerged in Wuhan, China in December of 2019 causing millions of people to become infected and thousands of deaths. Patients infected with the virus experienced a range of symptoms ranging from mild to severe with a large portion of the world population being asymptomatic carriers. Throughout the pandemic scientists observed a decrease in patients seeking medical care in both the emergent and non-emergent settings. There were a lot of journal articles showing this trend but many of them fail to explain why this trend occurred. Due to the lack of literature it was difficult to understand why patients would avoid seeking medical attention during the pandemic. The purpose of this literature review was to gather, examine, and assess the evidence that was available regarding the reasons why patients avoided seeking medical attention during the COVID-19 pandemic and the potential repercussions of said avoidance. It was found that the main reason patients avoided seeking medical care during the pandemic was due to the fear of being exposed to and potentially becoming infected with COVID-19 while seeking medical attention. Some other reasons that were found included misinformation about COVID-19, lack of social support, and large economic burden of seeking medical care. All of these factors led to patients avoiding medical care and delaying the best opportunity for treatment, resulting in negative health outcomes. Unfortunately, since the pandemic is still on-going, we will not be able to fully understand the lasting effects of the pandemic for many more years.
Poster 28: Localization of Transgenes for Drosophila Models of Myotonic Dystrophy Type 1
Authors: Andrea Waltrip, Shyanne Michael, Delaney Baratka, Madeline Brunt, Charlotte Russell; Research Advisor: Dr. Ginny Morriss

Myotonic Dystrophy Type 1, DM1, is a multi-systemic disorder that results from expression of expanded CTG repeats in the DMPK gene in humans. Three transgenic Drosophila melanogaster lines have been created containing 60, 250, or 480 CTG repeats to model DM1. The transgenic repeats are expressed using the GAL4/UAS system. Expression of long-repeat transgenes ((CTG)₂₅₀ and i(CTG)₄₈₀) produces phenotypes consistent with DM1, relative to control lines ((CTG)₆₀). The precise chromosomal location of insertion of the transgenes has not been reported. We are using both classical genetic and molecular approaches to localize CTG-repeat transgene insertion into the genome. To narrow down insertion location to a specific chromosome, we used GAL4 drivers on different chromosomes to drive expression of repeats and assessed phenotypic ratios of eye color, climbing capability, flight ability, and muscle degeneration, which is affected in DM1 flies. Results from the genetic analysis suggest that the (CTG)₂₅₀ and i(CTG)₄₈₀ transgenes are likely localized to chromosome 2 and the (CTG)₆₀ transgene is likely localized to chromosome 3. We will confirm our chromosome localization using fluorescent in situ hybridization (FISH) of polytene chromosome preparations, using transgene-specific probes and comparing the hybridization location to regions that hybridize chromosome-specific probes. FISH will allow us to further narrow down the location of transgene insertion, allowing targeting of smaller regions for sequencing to determine the exact insertion site. Knowing the location of the transgenes can allow for more practical mating schemes to study DM1 disease mechanisms, as well as provides crucial information for understanding transgene expression.
Poster 29: Triggering Apoptosis in Jurkat Cells with Proton Pump Inhibitors (PPIs)
Author: Kaitlin Saal; Research Advisors: Dr. April Wynn, Biology and Dr. Randall Reif, Chemistry

Proton pump inhibitors, also known as PPIs, often trigger apoptosis, or programmed cell death, by disrupting proton pump function and interfering with pH regulation that typically occurs within a cell. In this experiment, the effect of omeprazole, a known gastric reflux drug and PPI, specifically on the viability of Jurkat cells was examined. The cells were grown under standard conditions and stained with calcein AM to differentiate between healthy and dead cells. Three trials of each of the experimental groups (negative control, positive control, and omeprazole) were conducted. The negative control contained no drug, and the positive control included doxorubicin, a known chemotherapy drug. Pictures were captured using an inverted fluorescent microscope at 0, 6, 18, 21, 24, 27, and 30 hours, and Image J was used to calculate the means and standard deviations of cell size to estimate cell viability. While there was significant difference in the percent viability between the negative and positive controls, the paired t-test for sample means at time t=30 hours between the negative control and omeprazole of 0.1635 supports the null hypothesis and assumes statistical insignificance. Nevertheless, other PPIs are still being investigated to determine their effect on cell viability.
Poster 31: HSP90 and Triglyceride Levels in Partially Migratory Canada Geese
Author: Audra Cote; Research Advisor: Dr. Andrew Dolby

The Canada Goose (Branta canadensis) is a partial migrant species. Migratory geese fly to a variety of breeding grounds in North America and residents stay behind. The physiological costs and benefits of being a migratory versus resident Canada Goose has received little attention. In this study, I will examine the physiological differences between resident and migrant Canada Geese using HSP90 and triglyceride levels. HSP90 is an oxidative stress indicator, and it will help us compare stress between populations. Triglyceride tests will examine excess fats and potential obesity in resident populations possibly based on a more sedentary pattern of activity and diet. My prediction is that there will be a difference in HSP90 and triglyceride levels between resident and migrant Canada Geese populations, with high HSP90 associated with migratory and physiological stress and high triglyceride levels associated with a more sedentary activity level. I will collect data on HSP90 and triglyceride levels in both migratory and resident Canada Geese specimens donated by hunters in the Fredericksburg area. Body length measurements will be used to assign geese to migrant and resident categories. Assays on samples have been completed for triglyceride tests and will be available soon and graphs for these will be completed by the symposium as well as the HSP90 ELISA test. As this is an ongoing research project, we will add to current data in the spring with more samples and will continue to run Triglyceride and HSP90 tests on new samples. Data will be available for the symposium.
Poster 34: The Effects of the Estrous Stages on Voluntary Wheel Running and Anxiety in Female CD-1 Mice
Authors: Abigail Algeier, Emily Landry; Research Advisor: Dr. Parrish Waters

Most non-human female mammals, including mice, experience an estrous cycle, a regular hormonal release cycle following patterns similar to the menstrual cycle that maintains reproductive function and behavior. There are three stages or phases to the mouse estrous cycle: diestrus, proestrus, and estrus. Because these phases have a similar hormonal progression to the menstrual cycle, mice are an ideal model to study female reproduction. We asked the question: does the phase of estrous impact the amount of exercise, and does the exercise retain its anxiolytic properties? In this pilot project, we organized 15 CD-1 female mice into three groups of five representative of each estrous phase. We allowed the mouse groups to run on wheels only when in the appropriate phase of estrous. We tracked estrous by performing vaginal lavages and examining collected cells under a light microscope. We then used the wheel running data collected over 5 weeks to compare the distance run by each estrous group. We analyzed the data and decided to modify the experiment to include more animals per estrous group for better results.
Poster 36: Dietary Diversity of Bees in the Genus Bombus along an Urbanization Gradient
Authors: Curtis Kasiski, Eren Edwards, Harrison Miles; Research Advisor: Dr. Josephine Antwi

As land use change continues at a rapid pace, it is increasingly important to understand how such environmental alterations influence beneficial insects, including pollinators. In eastern North America, bumble bees, are an important group of pollinators within managed and non-managed ecosystems. Here, we investigated changes in dietary diversity and niche overlap across common bumble bee species along an urbanization gradient: highly urban, suburban, and rural. We caught 126 bumble bees belonging to B. griseocollis, B. impatiens, and B. bimaculatus. Bombus impatients seems less abundant in urbanized areas than in rural and suburban areas. We were also able to successfully amplify pollen collected from all three Bombus species. In the next phase of this study, we plan to use next generation sequencing to identify dietary diversity.
Poster 38: The effects of nutrient pollution on macroinvertebrate communities in Accokeek Creek and Potomac Creek
Author: Mika Bishton; Research Advisor: Dr. Abbie Tomba

Nutrient pollution is a growing issue in freshwater streams. Agriculture practices such as fertilization contribute to excess nutrients entering and polluting water systems. Tidal streams are used as feeding and spawning grounds for large biodiversity of organisms. These tidal streams are more susceptible to pollution, making them useful water quality indicators for larger watersheds. Macroinvertebrates are good bioindicators of stream health because they are accessible, sensitive to environmental changes, and taxa can be organized based on pollution tolerance. Accokeek Creek is a forested stream located within The Crow’s Nest Nature Preserve. Potomac Creek is a neighboring stream surrounded by agricultural land. In this study, we compare macroinvertebrate assemblages in Accokeek Creek and Potomac Creek to study the impacts of agricultural activity to better understand the relationship between nutrient pollution and macroinvertebrate community structure. To obtain macroinvertebrates, sediment samples were collected along the streams. Organisms were identified to the family level with the exception of Oligochaeta. To measure diversity, the Shannon-Wiener Index will be calculated. Water quality parameters including temperature, pH, electroconductivity, and dissolved oxygen were measured at each site. Nitrate and orthophosphate levels were analyzed at each site to determine nutrient contamination. We predict Potomac Creek will have higher nutrient pollution contamination than Accokeek Creek. If this were true, we can expect lower diversity in Potomac Creek with more pollutant tolerant taxa present compared to Accokeek.
Poster 41: The Effect of Multi-Phage Resistance Mutations in Bacillus thuringiensis subsp. kurstaki on Virulence to Manduca sexta Larvae
Author: Marianne Beaulieu; Research Advisor: Dr. Lynn Lewis

Antibiotic resistance has led to the rise of several dangerous and difficult to treat diseases, such as MRSA infections. The number of antibiotics effective against resistant bacteria are dwindling, so the solution may lie in other bactericidal agents. Phage therapy is the practice of treating bacterial infections with bacteriophages, viruses pathogenic to bacteria. This therapy is promising for a number of reasons; phages are naturally occurring in abundance, they are reproduced by the bacteria they infect, and they are capable of mutating to evade bacteria’s defenses. However, bacteria are also capable of mutating to evade phage infection. Bacterial resistance to phage infection does not necessarily carry the same implications as bacterial resistance to antibiotics. Unlike with antibiotic resistance, the mutation battle between bacteriophages and the bacteria they infect is on-going. Furthermore, there is evidence to indicate that some bacteria may pay a heavy price for resistance to phages, to the point where they may no longer be capable of causing disease in a host. This idea forms the basis for this research.
At the University of Mary Washington, the phage hunters program isolates phages pathogenic to Bacillus thuringiensis subsp. kurstaki (Btk). Btk is a common bacteria found in soil and is used as a pesticide for its pathogenicity to lepidopterans. This research will involve isolating multi phage-resistant strains of Btk and testing how the phage resistance affects its pathogenicity by inoculating Manduca sexta larvae, and observing how many, if any, survive.
Poster 42: Characterization of Two Novel Calcium Regulator Proteins in Toxoplasma gondii Growth and Invasion
Authors: Emily Sizemore, Abby Delapenha; Research Advisor: Dr. Swati Agrawal

Toxoplasma gondii is an opportunistic apicomplexan parasite infecting humans and livestock. Infection in immunocompromised individuals can cause neurological damage and infection during pregnancy can lead to fetal death. These parasites engage in a complex life cycle, involving repeated invasion of host cell and egress from the host cell. Calcium signaling is an important regulatory mechanism for many essential processes in the parasite including gliding motility (actomyosin-dependent mode of motion), invasion, and egress. Our work focused on two previously uncharacterized calcium regulator proteins. The proteins of interest were modified using the CRISPR-Cas 9 system to express the Auxin Degron system downstream of each gene. Our work demonstrates the localization of these proteins and the role of these proteins on parasite growth and fitness.
Poster 43: Differential Gene Expression in Myotonic Dystrophy
Author: Anna Harris; Research Advisor: Dr. Ginny Morriss

Myotonic Dystrophy type 1 (DM1) is a multisystemic disorder that decreases muscle function. Expansion of CTG repeats in the 3’ untranslated region of Dystrophia Myotonica-Protein Kinase (DMPK) gene is ultimately responsible for the skeletal muscle wasting phenotype in DM1. Using Gel electrophoresis, PCR, and qPCR the relationship between myokines and their role in DM1 were studied. RNA samples from mice were obtained and used to synthesize cDNA through DNase treatment and PCR. These samples were tested using gel electrophoresis to confirm adequacy. Myokine expression was then tested via qPCR and four genes: ActB, Cx3Cl1, TNFa, and IL6. Through analysis of these techniques, Cx3Cl1 and IL6 had results that were inconclusive. ActB and TNFa showed diverse amplification – ActB having minimal and varied amplification while TNFa displayed higher but more consistent amplification. These results indicate ActB and TNFa have a relationship with myokine expression that could be evaluated in further studies. Future studies will be conducted using the same methods and experiment with alternative methods to explore the role myokines play in DM1 related skeletal wasting.
Poster 44: An Inquiry into the Validity of the Tube-Test as a Measure of Dominance in Mice
Author: Tim Philbeck; Research Advisor: Dr. Parrish Waters

Mice are social animals, and interactions among individuals can provide valuable information related to behavioral and physiological processes. To better understand social relationships in mice, the Tube-Test was developed to easily measure behavioral dominance in cohorts of mice; although this method is not universally accepted as a reliable measure of social dominance, it holds the benefit of being rapid, low stress, and providing an objective measure of dominance. To address the controversial validity of the Tube-Test and to enhance our ability to discriminate dominant mice in social groups, I compared results from the Tube-Test to home-cage behavior, preputial gland size, and steroid hormone levels, all of which are more universally accepted (but more labor intensive) indicators of social dominance in mice. I housed mice in dyads and assigned them social ranks (i.e. dominant or subordinate) based on their proportion of wins during the Tube-Test (n = 6 dyads). Social rank influenced the duration of total aggression (t = -18.42, df = 4, p ≤ 0.05), although subordinate mice exhibited higher levels of aggression. I used Wilcoxon rank sum tests to compare corticosterone concentration and preputial gland size. Social rank did not influence either of these measures (corticosterone: W = 6, p = 0.7; preputial gland: W = 3, p = 0.7). My results from this pilot study suggest that the Tube-Test does not represent an effective method to measure dominance-like behavior or physiological changes in laboratory mice, although I am continuing this work with an additional cohort of mice.
Poster 45: Treatment of MRSA with Phage Cocktail
Author: Skylar Houston; Research Advisor: Dr. Lynn Lewis

A focus on phage therapy has increased in popularity within the western hemisphere over the last few years with the rise of antibiotic-resistant bacteria, such as methicillin-resistant Staphylococcus aureus (MRSA). Bacteriophages are a type of virus that infect a specific bacterium. The bacterial host’s replication machinery is used for viral replication and once the virus has replicated sufficiently the bacterium is normally lysed. The focus of this research is on the preparation and use of phage cocktails to treat Staphylococcus aureus infections. Phage cocktails involve the use of multiple bacteriophages to attack the bacteria, and are often touted as being more effective than use of monophage therapy. The goal of this study is to isolate several phages for use to develop an effective phage cocktail for use against Staphylococcus aureus. Purification and isolation will be done by standard procedures. Following this, high titer of the phages will be made and used to make different formulations of a phage cocktail. To assess effectiveness, both comparative spot plates and time kill assays will be used. This will be compared to an antibiotic commonly used to treat Staphylococcus aureus infections.
Poster 46: Targeting Novel Apoptosis Genes in Leishmania tarentolae Using CRISPR-Cas9 System
Author: Caroline Beasley; Research Advisor: Dr. Swati Agrawal

Leishmania is a unicellular parasite transmitted to humans through the bite of a sandfly. Recently, a protocol for the CRISPR-Cas9 system, a gene editing tool, has been developed for Leishmania, allowing for the tagging or knockout of specific genes. In this study, we targeted two genes: PF16, coding for a known flagellar motility protein, and PGAM5, coding for a protein potentially involved in apoptosis in Leishmania. By observing the effects of the knockout of these genes, we will better understand their function. To start we identified ideal conditions for growth of Leishmania tarentolae with Cas9. We then prepared blasticidin and puromycin repair cassettes and single guide RNA (sgRNA) for PF16 and PGAM5 respectively for transfection and use of CRISPR-Cas9. To culture the parasites, we compared growth in Minimum Essential Media (MEM) and Brain Heart Infusion (BHI). Cas9 expression in our Leishmania was associated with a hygromycin resistance gene, so hygromycin was added to media as a selective pressure for Cas9 cell lines. When the parasites reached a high density, we transfected with PGAM5 and PF16 cassettes and sgRNA. We found that L. tarentolae grew to a higher concentration in MEM than in BHI. The Cas9 gene was conserved in the parasites, indicating that hygromycin selective pressure was effective. The transfected parasites are currently under selection with Blasticidin and Puromycin, and will be screened for correct insertion. The procedures used in this study to culture and Leishmania will allow further investigation of the role of PGAM5 in apoptosis in Leishmania.
Poster 47: The Effect of Social Isolation on Depression-like Symptoms in Male Mice
Author: Dylan Crann; Research Advisor: Dr. Parrish Waters

Humans who experience social isolation are at risk of developing depressive disorders, which are typified by decreased energy expenditure, increased food consumption, and forgetfulness. Two physiological systems that influence depression in humans are the neurotrophin, BDNF, and the glucocorticoid, cortisol. These ligands are disrupted in humans with depression disorder and are implicated in stress-related behavioral changes in mice. This study combines behavioral and physiological approaches to understand the effects of social isolation in a model organism. As social isolation becomes more common in our society, it is more pressing to understand how it may influence our behavior and physiology and can lead to pathological states. I hypothesize that social isolation will increase the expression of depression-like symptoms in mice. To model activity, we measure total running distance, running speed, and circadian running. Energy expenditure can be monitored through changes in total body mass and food consumption. Memory tests such as the Barnes maze and the novel object recognition provide measures of separate modes of memory that are associated with human depression. Finally, in our lab, we have developed protocols to measure levels of BDNF and corticosterone, the cortisol equivalent in mice, using commercially available ELISA assays. I expect socially isolated mice to have higher body mass, lower measures of running activity, and lower scores on memory tests. I also expect socially isolated mice to exhibit higher levels of corticosterone and lower levels of BDNF compared to social mice.
Poster 48: Endothelial Tube Maintenance & Analysis in a Cell Culture Model for Myotonic Dystrophy Type 1
Authors: Jada Gundy, Arshpreet Brar, Samantha Schwarting; Research Advisor: Dr. Ginny Morriss

Myotonic dystrophy type 1 (DM1) is a multi-systemic condition that results in severe muscle weakening and wasting. DM1 is caused by an expanded region of CTG repeats in the 3’ untranslated end of the DMPK gene. A previous study showed angiogenesis as a major process affected in DM1 mice that displayed muscle wasting as angiogenic genes and myokines were affected in response to repeat expression. Human umbilical vein endothelial cells (HUVECs) were used as the model for DM1 vasculature and transfected with DMPK containing 960 CUG repeats or DMPK with 0 repeats. These cells were then imaged every three hours for 24 hours. Endothelial tube length and width were quantified using ImageJ. Endothelial tubes mock transfected showed little to no degradation over the 24 hour monitoring period. Endothelial tubes transfected with DT0 showed some tube degradation upon visual analysis with tube narrowing. Endothelial tubes transfected with DT960 showed severe tube network degradation in tube narrowing and tube shortening.
Poster 49: The Effect of Fluorouracil on Pathogenic and Nonpathogenic Oral Microorganisms and Microbial Interactions with Restorative and Preventative Measures
Author: Valeria Ortiz Jimenez; Research Advisor: Dr. Lynn Lewis

Concerning the oral flora, chemotherapy compromises the patient’s oral health through dysbiosis of oral microbiota and increases the prevalence of dental caries, gingivitis, oral mucositis, and xerostomia. This research aims to evaluate the effect of a common chemotherapeutic agent, Fluorouracil (5-FU), on certain microorganisms that are common within the oral cavity. The 5-FU is typically given intravenously and when it reaches the oral cavity, the dosage is significantly reduced. Therefore, varying concentrations (50 mM, 75 mM and 100 mM) of 5-FU will be used to simulate this. The microorganisms tested will be Lactobacillus rhamnosus, Streptococcus mutans, Enterococcus faecalis, Staphylococcus aureus, Escherichia coli and Pseudomonas aeruginosa. These are some of the most common ones found in the diverse oral microbiota and would, therefore, be beneficial to study. They are also associated with different oral conditions like periodontitis, the progression of caries and lesions, and inflammation. There are topical and oral products that can be applied or consumed in order to prevent the overgrowth of certain bacteria, while also protecting the tooth surface and gums. In evaluating the effect of 5-FU on the microorganisms, different restorative and preventative treatments will be tested in order to reduce and/or improve their effect on a patient’s oral cavity. Thee products include chlorhexidine, fluoride varnish, amoxicillin, penicillin and saltwater.
Poster 50: The effects of social isolation on GRIN2B NMDA-R in PFC of CD-1 mice
Author: Jessica Mimms; Research Advisor: Dr. Parrish Waters

Social stability is critical for the well-being of an individual animal. Unstable environments, where socialization is limited, can serve as a risk factor for the development of psychiatric disorders, including depression and anxiety. In social interactions with rodents, glutamate was found to interact with NMDA receptors to modulate social memory. This compelled us to examine how socialization and the lack thereof, may influence glutamate in the medial prefrontal cortex of mice. The medial prefrontal cortex plays an important role in social responses and behavior. We will also investigate the corticosterone levels of rodents to determine how stress and social behavior are related.

Earth and Environmental Sciences

Poster 26: Preliminary Survey of Total and Bioavailable Concentrations of Trace Metals in Surface Soils in the Kingston, Jamaica, Region
Authors: Faith Jones, Anna Velardi, Katherine Cook; Research Advisor: Dr. Melanie Szulczewski

This study investigated background levels of concerning metals in a variety of soils in and near Kingston, the capital of Jamaica. Minimal soil sample collection and analysis had occurred since a 1988 island-wide geochemical survey revealed very high concentrations of total Cd in many regions, along with elevated concentrations of As, Cu, Zn, and Cr in some types of soil, with background lead levels elevated only at specific polluted sites. An updated examination was deemed important due to a growing city population, increased fuel combustion, and intensive urban gardening. This study analyzed soils collected in 2022 for total metal concentrations, as well as bioavailable concentrations, previously only reported for lead. The various soils sampled from this urban and suburban region of a tropical country provided interesting results regarding metal content, with the arsenic and cadmium results of most concern.
Poster 30: Assessing the Presence and Concentration of Trace Metals in Surface Waters, Aquatic Plants, and Fish Adjacent to a Virginia Coal Ash Repository
Author: Carolyn Willmore; Research Advisor: Dr. Tyler Frankel

Coal ash (CA) is an industrial waste that has been shown to contain several neurotoxic trace metals including cadmium, arsenic, mercury, and lead. These contaminants are then able to leach into surrounding waterways and cause undesirable ecosystem effects. According to the Virginia Department of Environment, there are currently twenty-eight CA repositories that are situated near waterways which act as tributaries for the Chesapeake Bay, many of which are located adjacent to coal-fired powerplants. While previous studies have examined the presence and concentrations of these trace metals in surface water and sediments surrounding these industrial sites, our understanding of whether these trace metals bioaccumulate in aquatic flora and fauna inhabiting these waters remains relatively poor. As such, this study examined the presence and concentration of twelve different trace metals (Al, As, Cd, Ca, Cr, Cu, Fe, Pb, Mg, Mn, Se, Zn) in plant and fish tissues collected near the Possum Point Powerplant (Dumfries, VA). Male and female Banded killifish (Fundulus diaphanus) were collected from each site and epaxial muscle, gonads, and brain tissue collected via gross dissection. Whole hydrilla spp. were collected from each site. All collected samples were then oven-dried and trace metals extracted using 65% nitric acid, 30% hydrogen peroxide, and heat. Once extracted, concentrations of each metal were assessed using ICP-OES. While this study is still ongoing, we expect to find elevated concentrations of several neurotoxic trace metals in fish and plants collected adjacent to the plant compared to associated water and sediment samples, with increased bioconcentration exhibited by Hydrilla spp. The results of this study will provide a more detailed understanding of the large-scale impacts of this coal ash repository on adjacent waterways via bioaccumulation and serve as support for future studies examining impacts on higher tropic levels.
Poster 32: Calibrating a Multi-Coral Genus Approach for Reconstructing Central Tropical Pacific Climate
Author: Jacob Cantor; Research Advisor: Dr. Pamela Grothe

Centuries-long high-resolution climate records from the equatorial Pacific are vital to understanding the anthropogenic influence on tropical climate and validating future climate predictions in a warming world. Since instrumental records of climate only span through the mid-20th century, scientists use paleoclimate proxies from coral, or natural archives that capture climate conditions in their geochemistry, to reconstruct temperatures beyond the instrumental era. However, typical tropical Pacific paleoclimate studies are limited to one coral species, Porites, making it challenging to complete a centuries-long record of climate due to limited availability of samples. Here, we test the reliability of two new coral species, Favia and Hydnophora microconos, as recorders of climate in order increase the available archive to reconstruct a continuous 200-yr long climate record of the central tropical Pacific. Both living and fossil coral skeletons were collected from Kiritimati Atoll, central tropical Pacific, between 2014 and 2018 and were cut into 1-mm thick slabs, x-rayed, and drilled every millimeter along the main growth axis for geochemical analysis – δ18O and Sr/Ca – the gold standard for sea surface temperature (SST) reconstructions in corals. Initial results suggest that the δ18O timeseries from modern Favia closely resembles in-situ SST and δ18O records from Porites, suggesting it is an excellent recorder of SST. Future work will focus on δ18O and Sr/Ca records from modern Hydnophora microconos. If also proven reliable, then geochemical records from fossil Favia and Hydnophora microconos coral will be essential for completing a continuous 200-yr long record of central tropical Pacific climate.
Poster 35: Spatial analysis of dam sediments and trace metals contamination in the North Nashua River basin
Author: Jack Lanier; Research Advisor: Dr. Ben Odhiambo Kisila

Fitchburg, Massachusetts is a heavily industrialized city with over 20 dams located within the North Nashua River basin. Many of the dams, which were constructed in the mid- to late-1800’s, are abandoned. Metal fluxes and accumulation in fluvial ecosystems reflect natural weathering and associated sediment fluxes from the basin; but in most cases this process is exacerbated by the progressive anthropogenic land-use intensification with human population increases. It is well established that sediments trapped behind dams are a sink for contaminants from various land uses, known point sources, and atmospheric deposition. Therefore, spatial analysis of sediments behind multiple dams at high resolution in a single basin enables characterization of the dynamics between modern urbanization and legacy industry. This study seeks to characterize the spatial variability of metal concentrations in sediments behind multiple dams on the North Nashua River in order to infer the impact of land use and legacy industry on fluvial systems. Data collection consisted of multiple sediment cores and grab samples from seven dams in upstream to downstream locations along the North Nashua River. Samples were prepared using the aqua regia digestion method (USEPA 3050B) and were analyzed using an inductively coupled plasma mass spectrometer (ICP-MS) to determine metal concentrations in the surficial and core sediments of North Nashua River Basin. Preliminary results from trace metals enrichment analysis indicate significant to extreme enrichment of arsenic, cadmium, and lead, and low enrichment of copper and zinc. Specifically, As ranges from 1-15, Cd 1-250, Pb 1.5-15, Cu 0.1-6, and Zn 0.9-11. Initial hotspot analysis shows the greatest concentrations of metals in the south-central region of the study area; located adjacent to the town of Fitchburg and at the confluence of several sub-basins into the North Nashua River. Further Principal Component Analysis and other statistical analyses will elucidate the role of legacy sediments and contemporary land-use intensification in influencing metal distribution and loading in the North Nashua River Basin. This knowledge will provide a base for future research relating to contamination from the region’s industrial legacy and aid in any potential future remediation activities.
Poster 37: Assessing the Impacts of Two Coal Ash- Associated Trace Metals on the Viability, Locomotor Behavior, and Embryonic Development of the Freshwater Snail Planorbella Duryi
Author: Talia Tanner; Research Advisor, Dr. Tyler Frankel

Coal ash (CA) has been shown to contain several neurotoxic trace metals which are able to escape into local aquatic environments via accidental release, leaching from lined or unlined repositories, and permitted discharge. While previous studies have mainly focused on the impacts of these contaminants on freshwater teleosts, little is known about their effects on non-model aquatic invertebrate species. As such, this study assessed the exposure effects of two CA-associated trace metals, cadmium and arsenic, on the viability, locomotor behavior, and embryonic development of the Seminole ramshorn snail (Planorbella duryi). Exposure treatments were prepared at 0, .01, .1, 1, or 10 mg/L for each contaminant using either CdCl2 or Na2HAsO4 7H2O and concentrations confirmed using ICP-OES. Individual adult P. duryi were placed into separate 400mL beakers and exposed for 10 days, during which viability was assessed every 24hrs. Locomotor behaviors were recorded on days 1, 5, and 10 and analyzed using automated behavior software (ToxTrac v2.97) to assess differences in average speed, acceleration, distance travelled, and time spent immobile. Newly laid (<6hrs old) embryonic clutches were obtained from a breeding colony. Individual embryos were then isolated from each clutch, placed into separate glass petri dishes containing a given treatment, and checked daily for embryonic development stage and hatching success. While this study is currently ongoing, we expect to find dose-dependent decreases in locomotor behavior and delays in development for both trace metals, with viability being the least sensitive endpoint of those tested. Our results will provide novel information regarding these contaminants which will enhance our understanding of their impacts on invertebrate populations that inhabit CA-contaminated waterways.
Poster 39: The Presence, Distribution, and Concentration of Trace Metals in Surface Waters and Sediments Collected Near a Virginia Coal Ash Repository
Authors: Elizabeth Tyler, Rachael Harrington; Research Advisor: Dr. Tyler Frankel

The Chesapeake Bay watershed contains several coal-burning power stations located along its waterways. Coal ash, one of the largest forms of industrial waste, is primarily produced by power stations and disposed of in coal ash repositories. Known to be heavily enriched with trace metals, these contaminants are then able to enter surrounding aquatic environments. Few studies have examined trace metal contamination within the Potomac-Shenandoah watershed stemming from these repositories. Thus, the goal of this study was to assess the spatial and temporal distribution of trace metals in sediments adjacent to the Possum Point power station (Quantico, VA). Sediment samples (grab and core) were collected from several sites upstream, midstream, and downstream from the station. Trace metals from each sample were extracted and analyzed using ICP-OES (inductively coupled plasma optical emission spectroscopy) for the presence and concentration of Al, As, Cd, Ca, Cr, Cu, Fe, Pb, Mg, Mn, Se, and Zn. Cores were sectioned at 2cm intervals and sediment chronology established using 210Pb. While this study is still ongoing, we expect to find elevated concentrations of these metals midstream and downstream from the power station. Based on chronological data, we also expect to observe enriched trace metal deposits that occur after the coal ash repositories were created. This study will provide vital information regarding the prospective impacts of coal-burning repositories on the release and mobilization of trace metal contaminants within aquatic ecosystems in the Chesapeake Bay region.

Chemistry and Physics

Poster 25: Apoptosis Induction in Jurkat T Lymphocytes by Proton Pump Inhibitors (PPIs)
Author: Shreya Murali; Research Advisor: Dr. Randall Reif, Chemistry

Apoptosis, commonly known as programmed cell death, constantly occurs in humans. In healthy cells, proton pump proteins allow for H+ ions to permeate cellular membranes, regulating pH levels. However, proton pump inhibitors (PPIs), such as omeprazole, prevent proton movement, resulting in pH regulation limitations. As the cell increases in acidity, apoptosis is induced. In previous studies, omeprazole induced cell death in Jurkat T-Lymphocytes; however, there was no confirmation of whether the cells died through apoptosis, or through necrosis, where the cell bursts. In order to measure the extent of cell death, cytosolic esterase activity was measured by staining cells with Calcein-acetoxymethyl (AM) dye. Jurkat cells were exposed to PPIs omeprazole, dexlansoprazole, and esomeprazole for six-hours, and monitored for 30 hours to measure viability. Doxorubicin, a known chemotherapeutic, was also used as a positive control when testing viability. When imaged using fluorescence microscopy, if cells fluoresced, they were deemed viable, while nonfluorescent cells were deemed necrotic. At the 30-hour mark, dexlansoprazole had least viability (39.95 +/- 3.52%), followed by doxorubicin (62.86 +/- 1.80%), esomeprazole (66.24 +/- 1.59%), and omeprazole (69.29 +/- 2.01%), in comparison to the negative control (71.54 +/- 1.11%). The low viability of dexlansoprazole indicates the need for a toxicity study using the same PPIs and exposure methods, to determine the optimal drug concentration. Future studies include the use of Annexin V-FITC and propidium iodide (PI) dye to determine the ability of the PPIs to induce apoptosis.
Poster 27: A Quantum Rattleback Effect in Rotationally Asymmetric Molecules
Author: Madeline Killian; Research Advisor: Dr. Varun Makhija, Physics

The rattleback is a boat shaped toy with a non-uniform mass distribution. As a result, its principal axes of rotation do not coincide with geometrical symmetry axes. A rattleback exhibits unidirectional rotation when spun about a symmetry axis. Here we computationally investigate the rotational dynamics of C2H3Cl after interaction with a non-resonant, femtosecond laser pulse. C2H3Cl lacks an axis of rotational symmetry, as a result of which the principal axes of its moment of inertia and polarizability tensors do not coincide. The interaction with the laser pulse torques the molecule about the principal axes of the polarizability tensor, initiating rotation that is not about any one of the principal axes. We compute the time evolving probability distribution of molecular axes during and after this interaction by solving the Time Dependent Schrodinger Equation in the rigid rotor approximation. This probability distribution evidently exhibits a unidirectional rotational motion about the most polarizable molecular axis, similar to that of the classical rattleback. The effect can be traced back to Raman transitions occurring during interaction with the laser pulse that change the parity of K the projection of the rotational angular momentum on the most polarizable axis.
Poster 33: Solar powered phone charging stations for the homeless population
Author: Kevin Leong, Research Advisor: Dr. Desmond Villalba, Physics

We are building phone chargers powered by an array of solar panels for the homeless population. Smartphones have become implemented and almost essential for life in our society, everyone has one including those who are homeless. Unfortunately, some homeless people are unable to charge their phones, therefore, we are creating a way for them to do that in a cost efficient way for everyone. Creating this prototype had four big focuses: 3D printing, creating circuits, programming the circuits, and angling our solar array towards the sun. We have been able to create a circuit that can generate enough power to charge a phone, and we are programming our circuit to use that power for charging purposes. We then have been able to 3D print a container for our solar array and wiring and angle it where it would be the most efficient at producing energy. Results from our project show that we have been able to power an Arduino board with solar power, and the optimal angle at which the solar panels will collect the most energy at our location in the Summer is approximately 10 degrees and South facing.
Poster 40: Quadratic programming for generating minimized weight matrices for pre-optimized neural networks
Author: Clark Saben; Research Advisor: Dr. Varun Makhija, Physics and Dr. Tirthabir Biswas

We are finding alternative expressions that produce the same result as a neural network and comparing how each performs on new data. A neural network (NN) is a mathematical expression that can be composed of linear and nonlinear transformations (often referred to as a computation graph). A NN must also be differentiable in order for gradients to be calculated for each transformation inside of the computation graph. By process of stochastic gradient descent (SGD) w.r.t a variable in the computation graph known as a weight(s) to minimize a loss function (in a process known as training), a NN can be grafted to act as a predictive algorithm for some input signal. Weight variables after gradient descent generate reproducible outputs on input signals used during training. We introduce quadratic programming with constraint conditions to generate new weight variables that produce the same output from the input signals used in training. We compare the performance of the NN using each set of weight variables on new data.