School of Sciences, Mathematics, and Engineering

2022 Celebration of Summer Research

1.
Origin of Pancreatitis Associated Fibroblasts

Julia Piermattei¹, Lu Han¹, Wenyu Gou², Hongjun Wang² and Michael Ostrowski^1
1Department of Biochemistry and Molecular Biology, Medical University of South Carolina
²Department of Surgery, Medical University of South Carolina

Fibroblasts expand in both pancreatic cancer and pancreatitis, and they play important roles in both diseases.  Our previous studies show that the splanchnic mesenchyme is the origin of normal and cancer associated fibroblasts in the pancreas.  However, the origin of pancreatitis associated fibroblasts is unknown.  Our hypothesis is to determine if the splanchnic mesenchyme is also the origin of pancreatitis associated fibroblasts.  lsl1cre and tomato reporter genetic alleles are used to permanently label descendants from the splanchnic mesenchyme with tomato expression.  Chronic pancreatitis is induced in mice with TNBS injection to the pancreatic duct.  The pancreata were then dissected and imaged using an epifluorescence microscope.  This analysis showed an increase in tomato signal in the pancreatitis group compared to the control group.  The puncta pattern of the tomato signal in the pancreatitis group suggests that the tomato expression was in fibroblasts.  This preliminary data suggests that the splanchnic mesenchyme is the potential origin of pancreatitis associated fibroblasts.

2.
Effect of Complexation on Zinc Removal by Magnetic Nanoparticles

Casey O'Brien and Katherine Mullaugh
Department of Chemistry and Biochemistry, College of Charleston

Access to clean water is expected to decrease, particularly in low resource areas. To address this challenge, new water treatment methods will be needed. Removal of chemical contamination by magnetic nanoparticles (NPs) is one strategy that could be used to remove pollutants from water. Our studies show the model heavy metal zinc (Zn²⁺) can be readily removed from pristine solutions by adsorption to the surface of citrate-capped magnetite nanoparticles. However, real water matrices are far more complicated. Complexation of metals by ligands may interfere with the adsorption of metal cations onto NP surfaces. Experiments were performed with concentrations of inorganic (chloride, sulfate) and organic (ethylenediamine, citrate, NTA, EDTA) ligands. A decrease in adsorption was demonstrated when Zn²⁺ was strongly complexed. Experiments were conducted to examine the efficacy of NPs in more authentic water matrices. With the exception of seawater, the particles performed as well as when in a noncomplexing buffer.

3.
Using Hemolymph Chemistry to Predict and Assess Molting in Green Crabs, Carcinus maenas

Emily Dombrowski, Jason Goldstein and Laura Crane
Department of Biology, College of Charleston
National Oceanic and Atmospheric Administration
Wells National Estuarine Research Reserve

Invasive green crabs, Carcinus maenas, have resided in New England coastal waters for over 200 years and adversely impact shellfish populations. Harvesters and researchers are exploring population mitigation strategies, including implementing a soft shell green crab fishery. A primary challenge is effectively identifying pre-molt crabs. This project aims to evaluate the use of visual and biochemical cues in green crab hemolymph to predict molting. Green crabs were captured in Wells, ME and New Castle, NH, tagged, measured, and held in individual compartments in a “crab condo” in situ. Hemolymph samples were collected from each crab (n = 126) twice a week and evaluated for protein concentration, color, and calcium level. Preliminary data suggests a relationship between hemolymph protein and crab molting, as well as a correlation between hemolymph color and calcium content. These results are important in understanding the biological underpinnings of molting and in creating an accessible molting assay.

4.
Development of a Prototype and Calibration System to Characterize Natural Rain  

Lili F. Boss and Michael L. Larsen
Department of Physics and Astronomy, College of Charleston

One of the most important physical characteristics of an individual raindrop is its size. The size of a drop affects its microphysical properties such as its shape and fall speed. Instruments that measure the properties of individual drops are commercially available, but generally do not capture the drops for post-measurement analysis. While the literature has discussed multiple prototypes for capturing individual rain drops during rain events, the methods previously used were limited by the size of drops the acquisition system could collect. With acquisition systems that primarily were responsible for collecting and characterizing larger sized raindrops, smaller sized droplets are misrepresented in drop size distributions. The purpose of this project was to develop a system that can efficiently collect raindrops of all sizes that can be measured and stored for later biogeochemical analysis. A primary acquisition prototype was developed using 3D printed PLA plastic filters with heightened walls to allow for multiple drops to be simultaneously captured without allowing for drop-drop interactions or post-acquisition sample deterioration.

5.
Changes to Heterogeneous Ice Nucleation Rate Due to Changing Concentrations of Dilute Salt Solutions on an Insoluble Surface

Griffin Hall, Lili Boss, Michael L Larsen and Will Cantrell
Department of Physics and Astronomy, College of Charleston
Department of Physics, Michigan Technological University

Ice nucleation is a vital process in cloud physics. The community is engaging with a variety of open questions regarding the mechanisms that optimally facilitate the nucleation process. Recent work has investigated how changing the composition and/or concentration of water solutions may alter the nucleation rate on insoluble surfaces.

Here, we add to the discussion by presenting results from a series of experiments that investigated the change in ice nucleation capabilities as a function of molarity for dilute salt solutions (NaCl and (NH₄)₂SO₄) on insoluble surfaces. We used a freezing stage to slowly cool small (<10 microliter) salt solution drops in contact with an insoluble substrate. By measuring the freezing temperatures and surface contact areas of each drop, estimates of the heterogeneous ice nucleation rate coefficient were computed.

6.
Profiling the Response of Individual Gut Microbes to Common Nutritional Supplements Used in the Neonatal Intensive Care Unit (NICU)

Megan E. Waller¹, Caroline J. Eichhorn¹, Taylor D. Ticer², Janiece S. Glover¹, John E. Baatz^3,4, Carol L. Wagner^3,4, Melinda A. Engevik^1,2 and Katherine E. Chetta^3,4
1Department of Regenerative Medicine & Cell Biology, Medical University of South Carolina
²Department of Microbiology & Immunology, Medical University of South Carolina
³Department of Pediatrics, C.P. Darby Children’s Research Institute, Medical University of South Carolina
⁴Department of Pediatrics, Division of Neonatal-Perinatal Medicine, Medical University of South Carolina

Infant diet is a significant driver of the gut microbiota, which is intimately linked to the development of disease. This study examined the impact of preterm-infant NICU nutritional supplements on 16 commensal and 16 pathobiont microbes commonly found in the premature infant gut; these included preterm formula, thawed donor milk, fresh breast milk, with and without fortification, and others. To do so, we cultured bacteria in fully defined media, monitoring for growth after 20 hours of incubation. Findings indicate that pathobionts have significant growth with preterm formula, donor milk, and supplemented iron; pathobionts do not have a growth advantage with fresh milk, but the addition of fortifiers promotes their growth. We also found that commensals grow well with each dietary element, but growth was less enhanced with the addition of fortifiers. This data indicates that fortifiers and additional supplements may promote the growth of undesirable microbes in the infant gut.

7.
Real-time Drowsiness Detection for Driver's Safety at the Edge

James Grooms, Will Myrick and Navid Hashemi
Department of Computer Science, College of Charleston

The National Highway Traffic Safety Administration estimates that in 2017, 91,000 crashes involved drowsy drivers. To combat this, a pre-trained convolutional neural network (CNN), InceptionV3, was initialized and fine-tuned on the chosen drowsy driver image dataset from a publicly available dataset . InceptionV3 achieved a categorical accuracy of 88.91% on static images after extensive testing. The python library OpenCV was then used to access the webcam and implement the CNN on detecting drowsiness in real-time video. The model was then successfully deployed on a Jetson Xaiver edge computing device.

8.
Uniquely Microstructured Copolymers of epsilon-Caprolactone and TOSUO Monomer via Organic Catalysis

Adeline Barnes and Brooke A. Van Horn
Department of Chemistry and Biochemistry, College of Charleston

Polymer microstructure significantly influences material properties such as crystallinity and the rates and modes of hydrolytic degradation. Each of these characteristics are key for materials with biomedical applications. In my undergraduate research at the College of Charleston, I have employed organic catalysis over traditional metal-mediated ring opening polymerization (ROP) strategies for the preparation of novel biodegradable polyester copolymers of e-caprolactone (CL) and 1,4,8-trioxaspiro[4.6]–9-undecanone (TOSUO). TOSUO’s inclusion in the polymer chains allows for future derivatization of the polymers with biomedically-relevant ligands, such as X-ray imaging agents. Preliminary syntheses indicate a difference in the rate of incorporation of TOSUO compared to CL when prepared with the organic catalyst 1,5,7-triazabicyclo[4.4.0]dec-5-ene (TBD). Gradient copolymer products are observed when compared to the rates of incorporation observed for the Sn (II) (2-ethylhexanoate)-mediated polymerizations. This presentation will showcase my nuclear magnetic resonance (NMR) spectroscopy evidence of both crude aliquots of kinetic/set-time polymerizations and precipitated/isolated products.

9.
Epithelial-to-Mesenchymal Transition is a Minor Source of Pancreatic Cancer Associated Fibroblasts

Tom Walter, Lu Han and Micheal Ostrowski
Department of Biochemistry and Molecular Biology, Medical University of South Carolina

Pancreatic ductal adenocarcinoma is characterized by a dense stroma primarily made up of cancer associated fibroblasts (CAFs). Epithelial-to-mesenchymal transition has been previously proposed to be a potential source of these CAFs. The described project aims to test the hypothesis that pancreas epithelial cells are an origin of CAFs in PDAC. The mouse model used for this experiment employs the FlpO-Frt recombinase system: pancreas epithelial cell specific FlpO expression leads to expression of Kras^G12D and deletion of p53, causing tumorigenesis. Meanwhile, a FlpO dependent GFP reporter allele permanently causes epithelial cells and their descendants to express GFP. The pancreata of these mice were harvested, and immunostaining was used to identify the proportion of CAFs that were GFP positive. Using two different fibroblast markers, it was found that less that 1% of CAFs in these mice were GFP positive, suggesting that epithelial-to-mesenchymal transition contributes minimally to the PDAC CAF population.

10.
Outflows Present in Ultra-Luminous X-ray Sources (ULXs)

Callaway Hudson and P. Chris Fragile
Department of Physics and Astronomy, College of Charleston

Ultraluminous X-ray Sources (ULXs) are believed to be binary systems with primarily Stellar Mass Black Holes significantly distanced from any Active Galactic Nuclei with an observed Luminosity above the value predicted by the Eddington Limit. This limit is defined as the maximum luminosity a body can achieve before outgoing radiation pressure overwhelms incoming gravitational forces and excess material is no longer pulled in. For values above Eddington, it is believed that the observed luminosity of ULXs is not truly above this limit, but instead emitted from the polar regions as a highly narrowed beam; called jets, which can cause observations to show a luminosity potentially far exceeding predicted numbers. Another outflow in these ULXs arises from the accretion disk as a form of high-energy winds, which while both influence the outflow of the system the disk winds are primarily what will be discussed in this poster regarding outflows.

11.
MYdata- A Small Data Collection Device

Jo Jackley and Sarah Schoemann
Department of Computer Science, College of Charleston

MYdata is an application combined with a wearable device used to assist in Small Data collection. Small Data is smaller data sets used for personal insights. It focuses on a single concept and seeks to answer a question. An accessible way to collect, store, and process Small Data is needed. 

The device registers when a button is pressed and sends a signal over Bluetooth Low Energy to the mobile application. The device stores data whenever it is not connected to the application and sends it when connected. The device is inexpensive and easy to construct.

The application stores and processes the data, which is displayed in a variety of graphs and can be exported as a png and the raw data as an email. Anyone with coding experience can design new graphs.

12.
Solar Photodegradation of Metoprolol in Simulated Natural Water Samples

Heidi Sabatini and Wendy C. Cory
Department of Chemistry and Biochemistry, College of Charleston

As pharmaceutical contamination in our waterways increases, there is an urgent need to understand the behavior of pharmaceutically active compounds (PhACs) and their solar photodegradation products in the aquatic environment. Determining the rate of solar photodegradation and any potential transformation products in natural water samples is an important step in assessing the risk that pharmaceuticals pose to human and environmental health. In this research, metoprolol (MTP), a common blood pressure medicine, was investigated as a potential pharmaceutical pollutant. In order to study its solar photodegradation, samples were prepared in a dilute aqueous buffer solution (pH=7.0) to mimic realistic environmental conditions. Dissolved organic matter known as humic acid (HA) was added to investigate the possibility of indirect photodegradation. The solutions were photoexposed using a solar simulator to mimic natural sunlight and then analyzed using High Performance Liquid Chromatography (HPLC) to determine the rate of solar photodegradation. Results indicate that increasing concentration of HA caused an increase in the rate of degradation of MTP. Transformation products were observed using a Liquid Chromotography - Mass Spectrometer (LC-MS) and tandem MS was used to propose structures for these products.

13.
Utilizing Geographic Information Systems to Map Pollutants in Floodwaters of Charleston, SC 

Luke Haenel, Kevin Wright, Kalya Squiggins and Vijay Vulava
Department of Geology and Environmental Geosciences, College of Charleston

Floodwaters are a medium between the general populace and pollutants–trace metals and fecal bacteria–posing a health risk. While inorganic pollutants and fecal bacteria are known to be present in Charleston floodwaters, antibiotic-resistant fecal coliform bacteria (ARFC) are not yet quantified. To characterize the nature of floodwaters in the Charleston peninsula, water quality was measured at four select locations. These include sites that are tidally-influenced, stormwater runoff-influenced, and two influenced by tides and rainfall. During sample collection, water quality and meteorological data were recorded on-site using Survey123. After, some samples were analyzed for nutrient and trace metal concentrations while others were cultured with sterilized water, erythromycin, ampicillin, or ciprofloxacin to assess antibiotic resistance of ARFC. Collected data were analyzed for their spatial relationships using geographic information systems (GIS). Organizing representative sites across Charleston by water input, allows the unknown gaps to be concluded, creating a geospatial profile of the city’s floodwaters.

14.
Fragmentation Behavior of Linear Tri-depsipeptides in Positive Ion Mode 

Brison A. Shira, Michael W. Giuliano and Jay G. Forsythe
Department of Chemistry and Biochemistry, College of Charleston

Depsipeptides are polymers like the peptides that comprise proteins. However, they vary from proteins in that they incorporate hydroxy acids in addition to the proteinogenic amino acids. This means that at key positions where nitrogen atoms are normally found, there are oxygen atoms. Mass spectrometry (MS) is used to sequence (determine the order of their monomer incorporation) these compounds, which are important in areas such as natural products chemistry and origins-of-life research. Peptides can be easily sequenced with MS, but because depsipeptides have a different chemical composition, the peptide sequencing protocols cannot be used on depsipeptides. This project aims to bridge this gap. Because sequencing depends on fragmenting the molecules with tandem MS (MS/MS), this project aims to compare peptide and depsipeptide fragmentation mechanisms, using modeling and experiments on synthetic standards. Ultimately, this project seeks to enable rapid depsipeptide sequencing and improved experimentation with protein-like prebiotic compounds.

15.
Improving NOAA High Tide Predictions Using Python 

Angela Nganga, Juliana Martel, Norman Levine and Lancie Affonso
Department of Geology and Environmental Geosciences, College of Charleston
Department of Computer Science, College of Charleston

Flooding is a common problem for residents in the Lowcountry. The goal of this project is to provide useful tide predictions for the South Carolina Sea Grant Consortium funded Flood map App project. Currently, Charleston is used as a time reference at which the high tide occurs across SC. By using tide data from the National Oceanic and Atmospheric Administration (NOAA) site and the Hohonu tide monitoring site, an evident time shift was seen across all the tide gauges along the coast. To make tide predictions, regression analysis was performed to determine which factors affect the time shift in the high tides. Using this analysis, a model was made and was very accurate for inland locations. Therefore, this model is limited to locations similar to the ones used for the analysis. In the future, separate models can be made for different zones along the coast to provide accurate predictions.

16.
Incorporating Active Learning into Calculus Deconstruct Journals

Alex Baham, Kamryn Schemine, Kathryn Pedings-Behling and Amy Langville
Department of Mathematics, College of Charleston

Most calculus books are a printed form of a lecture, and most calculus teachers teach the way they have been taught from such books. Students passively learn by following example problems worked step-by-step; however, the students are learning by patterns and memorization, without understanding the reasoning behind the process being taught. In contrast, Deconstruct Calculus journals emphasize what is missing: the active learning of concepts. The journals are workbooks that are interactive, participatory, hands-on, conceptual, and personalized. A whole new definition of learning calculus is ahead of us. This summer, our team explored different active-learning techniques from master educators and worked to apply those concepts to our calculus curriculum. These ideas will be field tested during the fall semester allowing us to gather data to further guide our innovative approach.

17.
Elucidating the Role of Biologically Relevant Proteins in G Protein-Coupled Receptor Kinase 2-Mediated β-Arrestin Recruitment to the D2 Dopamine Receptor

Kirsten Snyder^1,2, Noelia Boldiszar¹, Marta Sanchez-Soto¹ and David Sibley^1
1National Institute of Neurological Disorders and Stroke (NIH)
²Department of Biology, College of Charleston

The D2 dopamine receptor (D2R) is a G protein-coupled receptor (GPCR) implicated in cognition, movement, reward, and emotion, and is a common target for many therapeutics. G protein-coupled receptor kinases (GRKs) phosphorylate GPCRs, promoting recruitment of β-arrestin, an important scaffolding protein. However, we have shown that β-arrestin recruitment occurs independently of D2R phosphorylation. Nonetheless, GRK2-catalytic activity is necessary for β-arrestin recruitment to this receptor. While it is clear that GRK2-mediated phosphorylation modulates recruitment to the D2R, its protein substrate remains unknown. This study seeks to identify novel phosphorylation targets for GRK2 to better understand GRK-modulated β-arrestin recruitment. We transfected the D2R into wild-type HEK293 cells or GRK-knockout cells, made via CRISPR, to identify differentially phosphorylated proteins. We assessed the impact of overexpression and pharmacological inhibition on β-arrestin recruitment to the D2R using BRET-based assays. Proteins found to affect recruitment will be further evaluated to determine if they are GRK substrates.

18.
Activation of Microglia Cells When Exposed to Stress

Devki Bhatt, Constanza Garcia-Keller, Stephen Walterhouse and Michael Meyerink
Department of Neuroscience, Medical University of South Carolina

Post-traumatic stress disorder (PTSD) is a common psychological disorder that affects many people who have experienced triggering events. Substance use disorder (SUD) can be paired with PTSD in that people who suffer from PTSD are more likely to take part in substance abuse, such as alcohol and drugs, specifically cocaine. Previous studies have shown that stress may have similar effects on certain parts of the brain as substance abuse. Rodent models were used to study acute and long-term stress to see how the microglia cells in the Nucleus Accumbens core are impacted and how it affects addiction. The outcome being that activated microglia decreased in acute stress yet increased in long-term stress was unexpected and will continue to be studied for further information.

19.
Ice-Binding Expression Profiles of the Psychrotolerant Halophile Halohasta litchfieldiae

Joelle Reich, Michael Janech and Matthew Rhodes
Department of Biology, College of Charleston

Sub-freezing conditions are considered to be one of the most inhospitable environments to microbial life, as ice crystals can puncture the cell wall of microorganisms and cause irreparable damage. Two evolutionary strategies for life to survive in sub-zero environments are either to inhibit ice from growing using antifreeze or Ice Binding Proteins (IBPs) or to reside in hypersaline environments with depressed freezing temperatures. IBPs have been isolated from both the Bacterial and Eukaryotic domains. Genomic screens have identified a handful of members of the Archaea with the DUF3494 protein domain. To date the DUF3494 domain, has been found to exclusively produce IBPs. One of the organisms containing a DUF3494 protein is the psychrotolerent hyperhalophile Halohasta litchfieldiae. Here we have worked to isolate and characterize the putative IBP from H. litchfieldiae. Using a series of freeze thaw cycles we have successfully bound and isolated a protein from H. litchfieldiae to ice. Further characterization awaits analysis using mass spectroscopy. If H. litchfieldiae is shown to produce an IBP the combined strategies of hypersaline residence with the production of an antifreeze IBP protein may represent a novel and highly effective strategy for cold adaptation.

20.
Synthesis of P(CL-co-TOSUO) Polymers Using Sn Catalysts  

Brooke Van Horn, Jennie Jackson, Addie Barnes and Nick Orlando
Department of Chemistry and Biochemistry, College of Charleston

The preventative approach of engineering antimicrobial materials as opposed to the reactive method of killing microorganisms after they have infiltrated a surface, could prove revolutionary to the field of medicine. Over the course of research this fall, I am looking to build on previous research in our lab synthesizing TOSUO PCL copolymer, a potentially antimicrobial agent, with various ratios of solvents, catalysts, and reactants. My objective is to study the chemical characteristics of the copolymer, which will provide a foundation for its incorporation into larger compounds and eventually pharmosudomedical materials. Because the rate of hydrolytic degradation of polyester material depends in part on the accessibility of the polymer backbone to water, analysis of PCL-co-TOSUO polymer by means of DCS  (differential scanning calorimetry) and MALDI (matrix assisted laser desorption/ionization), will allow our team to further characterize shorter chain length polymers as well as degradation patterns of rendered antimicrobial polymer.

21.
Solvent-free Ion-selective Potassium Ionophore-based Lipid Nanoparticles for Cellular Imaging

Ellie Kraichely, Nasrin Ghanbari Ghalehjoughi and Xuewei Wang
Department of Chemistry, Virginia Commonwealth University

Necrosis is often associated with solid organ tumors and involves necrotic cells releasing their intracellular substances into the microenvironment of a tumor.  The cytoplasm in these cells contain high levels of K⁺ which is then released into the extracellular fluid of a tumor. This 5-10-fold increase in K⁺ concentrations is harmful as it hinders the function of effector T cells surrounding the tumor. This project aims to develop ion-selective sensors to quantify and monitor these K⁺ concentrations in the extracellular environment. Previous fabrication methods of ion-selective sensors involve solvents to dissolve sensing chemicals. A volatile solvent is used so that it may be removed at the end of the fabrication process via evaporation. These methods may leave residual solvent in the nanoparticle which may cause cytotoxicity, and or affect the response of nanooptodes. Therefore, this project presents a new method of fabrication in which solvent is not used.

22.
Effects of the Eastern Mud Snail on the Community Structure of Benthic Microalgae

Timara Vereen, Kristina Hill-Spanik, Josiah Waters and Craig Plante
Department of Biology, College of Charleston

Benthic microalgae (BMA) are major contributors to ecosystem function as primary producers, with diatoms typically dominating. In October 2021, we examined impacts of the abundant mudsnail, Ilyanassa obsoleta, on BMA communities using two treatments (snails included, snails excluded) and controls (n=10 each) on a Charleston mudflat. At t=0 and t=14 days, sediment was sampled for chlorophyll a (biomass) and DNA (diatom diversity and composition). We found significantly more biomass in the no-snail compared to the snail treatment (p=0.017) and in both treatments compared to the control (p=0.001). Treatments appeared to have no effect on diversity, but there was a temporal effect (p=0.036). There were significant differences in community structure at t=14 between the no-snail treatment and control (p=0.002), suggesting a snail effect. Strong quantitative and subtle qualitative results suggest that snail abundance influences the mudflat microbial loop.

23.
Localization of Rings and Categories 

Terence Carey and Oleg Smirnov
Department of Mathematics, College of Charleston

In algebra, a ring is a collection of elements (e.g. integers or matrices) with some way to add, subtract, and multiply those elements. A preadditive category is essentially a ring where addition, subtraction, and multiplication are only partially defined based on where the 'elements' of the category point to and from. Conversely, a ring can be thought of as a preadditive category with fully defined operations. Generally, one cannot divide by the elements in a ring or a category. The localization of a ring or category is a related object in which it is possible to divide by specific elements. Due to the aforementioned connection between rings and preadditive categories, understanding localization for one aids us in understanding localization of the other and helps us develop a unified method of localization that works for rings and preadditive categories, as well as semigroups and categories.

24.
MALDI-TOF MS of Model Primordial Peptides with Nonproteinogenic Isomers of Valine

Alexis V. Torrence¹, Jui Patel¹, Mary Britt McDonald¹, Ronja Peter² and Jay G. Forsythe^1
1Department of Chemistry and Biochemistry, College of Charleston
²Analytical and Bioanalytical Chemistry, Hochschule Aalen

Depsipeptides are copolymers of amino acids (AAs) and hydroxy acids (HAs) and may have been precursors to polypeptides on primordial Earth. Unlike traditional peptides, depsipeptides form easily in simple chemical reactions which likely occurred in the primordial soup. The goal of this study was to investigate depsipeptide incorporation of the AA valine and its nonproteinogenic isomers isovaline and norvaline. It is generally thought that all were all available in primordial environments, yet only valine is genetically encoded. Why did biology select valine over its other isomers? In order to begin investigating this question, we compared the incorporation of valine to its nonprotein isomers in depsipeptides using matrix-assisted laser desorption/ionization – time of flight (MALDI-TOF) mass spectrometry.

25.
The Role of the Perirhinal Cortex to Nucleus Accumbens Neural Circuit on Novelty Recognition in Methamphetamine Self-Administered Rats

Dylan L. Freels, Katharine H. Nelson, Jordan L. Hopkins, Samuel K. Wood, Jordan S. Carter, Adam R. Denton, Stacia I. Lewandowski, Michael D. Scofield and Carmela M. Reichel
Department of Neuroscience, Medical University of South Carolina

The Perirhinal Cortex (Prh) to Nucleus Accumbens (NAc) neural circuit is hypothesized to be a critical component in cognitive deficits caused by long-term methamphetamine (meth) use and in relapse.  The potential for relapse was tested using a novel cue procedure in which a novel lever competes with a meth-associated lever.  To investigate the behavioral significance of the Prh-NAc pathway, the circuit was manipulated with a dual virus strategy in both Long-Access (LgA) and Short-Access (ShA) rats.  Inactivation of the circuit resulted in increased responding on the meth-associated lever relative to the novel lever, whereas vehicle resulted in similar responding on both levers. Activation of the circuit was unexpectedly without effect.  These results suggest that inhibition of the Prh-NAc circuit in the ShA procedure is sufficient to shift behavior away from novel stimuli, however activation of the pathway in the LgA “addicted” phenotype is not sufficient to shift behavior.

26.
Expanding Freshwater Sponge Surveys in South Carolina

Josephine Shostak and Christopher Freeman
Department of Biology, College of Charleston

Sponges are critical filter feeders found in many freshwater environments, but, to our knowledge, no studies have assessed their distribution and diversity in South Carolina. In the last two years, we have visited over 50 locations in South Carolina including rivers and lakes from Charleston to the NC and GA borders. Sponges were found on diverse substrates at 30 of these sites with up to three species at a single site. Sponges were identified via spicules and, when present, gemmules. We have now found at least 12 different species and, of these, we estimate that approximately five are new records for SC and two may be new species. We are also currently conducting DNA barcoding for molecular identification of these samples. This work sheds light on an understudied group and expands our understanding of the biodiversity in freshwater systems of South Carolina and the Southeastern United States.

27.
Green Synthesis of Reduced Graphene Oxide using Combined Reduction Methods

Alem Teklu, Erin Santanello and Noah Kern
Department of Physics and Astronomy, College of Charleston

Thermal and photochemical methods of reducing the oxygen content in graphene oxide (rGO) have proven successful - but with individual limitations that prevent its practical mass production. Certain variations of these methods require hazardous chemicals, vacuum or inert gases, or high temperatures, while other green variations struggle to remove stable oxygen-containing groups (OCGs). This paper presents a combination of green methods, photochemical and low-temperature thermal, using one method to target the groups that prove difficult to reduce with the other. These methods were performed sequentially and simultaneously to analyze their individual effects and limitations. The reduction of oxygen content was confirmed by characterization measurements performed by x-ray diffraction (XRD) and atomic force microscopy (AFM).

28.
Developing Interactive, Distributed, Smartphone-Based, Immersive Experiences for Music and Art

Meghan Gillikin and Bill Manaris
Department of Computer Science, College of Charleston

This project presents a smartphone-based environment for developing interactive, distributed music and art applications, installations, and experiences. This system facilitates audience engagement through participation via personal smartphones, possibly connecting with traditional computing devices via the Internet, without requiring software downloads or special configurations. This approach has been inspired and partially motivated by the COVID-19 pandemic, and builds on earlier research. It provides an efficient design approach for artists to create highly-distributed, participatory, immersive music and art experiences, by utilizing various input sensors and actuators available in today’s smartphones – these include smartphone accelerometers, video cameras, speakers, and screen displays.  We present five case studies to demonstrate our system and approach.  Hopefully, these may inspire new avenues for artistic creativity and expression towards building smartphone-based, immersive installations/performances for music and art in the 21st century.

29.
Investigating the Presence of Antibiotic-Resistant Bacteria, and Nutrients in Urban Floodwaters on the Charleston Peninsula 

Kevin Wright, Luke Haenel, Kayla Squiggins and Vijay Vulava
Department of Geology and Environmental Geosciences, College of Charleston

Urban flooding is a common problem on the Charleston Peninsula. Residents often have to navigate through standing water left by rain events, and or higher than normal tides. Sea-level rise and an increase in storms driven by climate change will exacerbate coastal flooding issues. Harmful contaminants including antibiotic-resistant fecal coliform bacteria (AFRC) may be present making urban floodwaters a public health issue. Water samples were collected during rain events at sites prone to flooding. On-site, water quality parameters including pH, temperature, and dissolved oxygen were recorded. In the lab, samples were analyzed for nutrient concentrations and cultured with antibiotics. Samples from all sites produced AFRC colonies. Sites with a more urban footprint were found to have higher concentrations of antibiotic-resistant colony-forming bacteria as well as higher concentrations of nitrates, and phosphates. This study implies that urban floodwaters pose a health risk to Charleston residents and visitors. 

30.
Hydrodynamic Simulations of Hot Jupiter Outflows Around Active Stars

Aly Nida, Ana Uribe and Joe Carson
Department of Physics and Astronomy, College of Charleston 

The evolution of the atmospheres of hot Jupiter type exoplanets is a topic of great interest and much remains to be discovered. Specifically, the behaviors of hot Jupiter atmospheres when subjected to high levels of stellar activity is subject to ongoing investigation. Here, the atmospheric conditions of three exoplanets around active stars are explored. Numerical hydrodynamic simulations were performed with the PLUTO code to provide upper limits of mass loss rates for the atmospheric outflows of WASP 107b, WASP 69b, and HD 189733b. These targets were chosen for the notable helium absorption lines in their atmospheres, indicative of activity and extreme-ultraviolet emission in their host stars. We also explored the role played by boundary conditions at the surface of the planet. For all three systems, we find the presence of outflows and calculate the radial profiles of their escaping atmospheres.

31.
Geochemical Study of Magma Mixing at Lassen Volcano, California

Bella Fleck, Abby Harper, Ray DePalma and John Chadwick
Department of Geology and Environmental Geosciences, College of Charleston

Lassen Volcano in northern California is the southernmost volcano in the Cascade Range, which extends north to Canada. Cascade volcanism is caused by subduction, where oceanic crust dives under western North America continental crust.  Lassen is unique in that it is also located in an area of Basin and Range extension, where the crust is being pulled apart.  Arc volcanism and Basin and Range extension produce two chemically distinct magmas, and we believe that magma mixing is forming a hybrid magma type found at Lassen.  Twenty lava rock samples were collected from flows near Lassen this summer and were then prepared for chemical and mineralogical analysis. Major and trace elements and radiogenic isotopes, as well as disequilibrium minerals, show evidence for magma mixing. Our preliminary field and lab work, funded by SURF and SSM Summer grants, point to two separate melting processes contributing to Lassen volcanism.

32.
The Effect of Temperature on Arabidopsis thaliana Germination Rates

Christian Hamner, Courtney Murren and Matt Rutter
Department of Biology, College of Charleston

Climate change is predicted to affect germination rates. In order to examine this effect, germination rates of Arabidopsis thaliana were examined across three PCR chambers at 11℃, 22℃, and 26℃ for two weeks to simulate natural environments. PCR machines provided a constant temperature across all chambers, allowing maximum exposure for the experiment’s time duration. Machine errors included gradients not being established within each chamber and the 22℃ chamber lid performing the temperature instead of the wells; these errors could have led to altered germination rates. However, rates were examined to not be altered given literature reviews on the average day of germination per temperature. Single-inserted T-DNA seeds and one natural accession, Col_0, were chosen. The warm chamber was expected to have the highest cumulative germ rate, cold the slowest. Results showed that the warm chamber had the highest cumulative germ rates with no significance found between cold and moderate.

33.
Evaluating the Relationship Between Elevated Arsenic in Groundwater Wells and Geologic Features in the Piedmont of North and South Carolina

Audrey Hayes¹, Erin Beutel¹ and Lauren Eaves^2
1Department of Geology and Environmental Geosciences, College of Charleston
²UNC Chapel Hill

Naturally occurring arsenic (As) well above EPA regulation levels is present in many bedrock wells throughout the Piedmont of North and South Carolina. The highest concentrations exist within the Carolina Slate Belt (CSB). However, even within the CSB, arsenic levels vary drastically between undetectable and above 8 ppm. We combined remote sensing data with existing geologic maps and individual well As levels to determine a probable cause. Two components likely control natural As levels in the groundwater; groundwater flow and the concentration of natural As in bedrock. We identified a bedrock source, the southern Gold Hill Shear Zone and the meta-mudstone tuff member (Zcm) of the Late Proterozoic. A local fracture pattern not seen elsewhere in the CSB may facilitate the localized high As levels through groundwater flow.

34.
Calibration of Projected Rotational Velocities vs. Widths of Stars Using STIS Observations

Laura R. Penny and Rhian Purves
Department of Physics and Astronomy, College of Charleston

There is a correlation between the projected rotational velocity of a star and the width of the peak in its cross-correlation function. We used observations of stars in the Small and Large Magellanic Clouds (SMC & LMC) taken by the Ultraviolet Legacy Library of Young Stars as Essential Standards (ULYSSES) project, specifically those taken using the Space Telescope Imaging Spectrograph (STIS) on the Hubble Space Telescope (HST). We cross-correlated the data with synthetic spectra and fitted the cross-correlation functions with a Gaussian to find the width of the peaks. These widths were plotted against the known rotational velocities for a set of stars and a calibration curve was fitted to allow the rotational velocities of other stars to be found from their widths.

35.
Effects of Elevated Salinity on Predator-Prey Behaviors in Amphibian Tadpoles and Dragonfly Nymphs

Amanda Montgomery and Allison Welch
Department of Biology, College of Charleston

Increased salinity in freshwater habitats is a major ecological concern. Habitat salinization can cause behavioral changes, reduced growth, and even death in various freshwater organisms.  Salinity can have an impact on individual organisms, but less is known about the impact on interspecies interactions.  Salinity tolerance trials with nymphs of the odonates Pachydiplax longipennis and Erythemis simplicicollis indicated moderate tolerance to salinities up to 12ppt. Predation trials were also conducted, in which Erythemis simplicicollis nymphs were allowed to feed on tadpoles of the green treefrog, Hyla cinerea. In the elevated salinity treatment, with tadpoles and nymphs acclimated to 6ppt, odonates had a higher rate of tadpole consumption than in the freshwater control.  These findings suggest that tadpoles, which are less tolerant to elevated salinity than their odonate predators, are more vulnerable to predation in elevated salinity, which could impact amphibian populations and ultimately the health of the community and ecosystem.

36.
The Effect of Elevated Salinity on Oviposition Site Choice and Mate Choice in Squirrel Treefrogs (Hyla squirella)

Regan M. Honeycutt and Allison M. Welch
Department of Biology, College of Charleston

Anthropogenic change challenges organisms with novel conditions in which existing traits may prove maladaptive. Although evolution optimizes fitness, competing demands in rapidly changing environments can undermine previously adaptive behaviors. For many animals, mate choice and oviposition site choice are co-occurring determinants of offspring success. Salinization is a current threat to freshwater systems globally, impacting many habitats in which amphibians breed and develop. We characterized the mating calls of male squirrel treefrog (Hyla squirella) from a local population and investigated how female squirrel treefrogs responded to variation in oviposition site salinity and in male advertisement call frequency. Although male call properties were similar to those previously reported in other populations, contrary to previous studies, female squirrel treefrogs in our study showed no preference for calls with lower frequencies. This discrepancy with previous results suggests that our methodology for assessing female preference may need refinement.

37.
Synthesis of Magnetic Nanoparticles for the Treatment of Water 

Jeff Luecken and Katherine Mullaugh
Department of Chemistry and Biochemistry, College of Charleston

The quality of water resources is threatened due to rapid industrialization, water-intensive agricultural practices, and climate-related changes to precipitation patterns. A suitable method of water treatment is the addition of magnetic nanoparticles that adsorb pollutants. The goal of this research is to develop a low cost, sustainable, and eco-friendly synthesis of magnetite nanoparticles (Fe₃O₄ NPs) that are non-toxic, water compatible, and reusable. The nanoparticles were characterized by dynamic light scattering (DLS), Fourier-transform infrared (FT-IR) spectroscopy and transmission electron microscopy (TEM). The Fe₃O₄ NPs were generally < 100 nm in diameter and present in larger aggregates in solution. The results of adsorption experiments, using zinc (Zn²⁺) as a model heavy metal, showed that lowering the concentration of hydroxide and increasing the concentration of capping agent assists in the adsorption while atmosphere and volume seem to have little to no effect on the efficacy of the nanoparticles.

38.
Investigating the Effect of Episodic Stellar Activity on Planetary Evolution

James Dockery and Joe Carson
Department of Physics and Astronomy, College of Charleston

The effects of episodic stellar activity on planetary evolution are not fully understood, yet such activity could dramatically influence planetary atmospheres and consequently, planets’ habitability. To improve our comprehension of stellar activity, our collaborators observed the M-type target stars AT Microscopii, AU Microscopii, and B-type b Centauri with the One Meter Telescope and FIDEOS spectrograph at La Silla Observatory. M type stars, as the most abundant stars in the universe, potentially have universal implications about the existential probability of extraterrestrial life. The CERES pipeline, developed by Rafael Brahm, was used to reduce the raw spectra for the extraction of stellar parameters and activity indicators, whose variability was determined by observing the target stars over multiple nights. This study’s results will serve as inputs into collaborators’ computer simulations predicting the influence of stellar activity on the atmospheric escape.

39.
Biting and Fighting: Dentitional Puncture Performance and Integumentary Puncture Resistance in Sharks and Moray Eels

Melanie Fischer, Christian Simmons and Andrew Clark
Department of Biology, College of Charleston 

Moray eels and sharks are apex marine predators in coral reef ecosystems. Hostile interactions between sharks and morays usually increase when prey abundance drops. The outcome of these altercations depends on their biting performance and the protective qualities of their integument. To assess if one of these taxa is more or less adapted to fighting, we performed a series of puncture tests to measure 1) the puncture performance of moray teeth and shark teeth and 2) the puncture resistance of moray skins and shark skins. Moray teeth require 33% less force and 67% less travel distance to puncture skin. The skins of morays are more puncture resistant, requiring four times the force and three times the travel distance required for puncturing shark skins. These data suggest that morays are more adapted for combat, however, our lab results are at odds with field data.

40.
Developing Methods for Inducing Fine Root Senescence

Maya C. Allen and Seth G. Pritchard
Department of Biology, College of Charleston

A more complete understanding of fine root death is necessary for climate models to capture the movement of C and N held within fine roots. No methods known to the authors yet exist for causing death to fine roots in a way that emulates natural senescence. We propose a heat-girdling method and discuss preliminary data. A heat-girdling tool was crafted for inducing senescence in roots of peas grown in-lab in rhizoboxes. Root senescence was characterized with dissection microscopy and vital staining over several weeks. Heat-girdling halted normal root growth and caused death to the phloem and cortical tissues while appearing to leave the xylem intact. This groundwork should be built upon with study of root diameter in relation to necessary heat intensity/duration for inducing senescence and of diameter fluctuations following heat-girdling to give further insight into root response, along with confirmation of intact xylem transport function.

41.
Solar Photodegradation of Propranolol in Simulated Nature Water

Kyra Dorsey and Wendy Cory
Department of Chemistry and Biochemistry, College of Charleston

Pharmaceuticals are a part of everyday life. As a result, they enter the waterways after passing through a water treatment plant that was not designed to remove them. Once in the water ways, they pose a threat to the health of the environment. These medications breakdown over time from exposure to sunlight and organic materials. The resulting degradation products are also pollutants that can negatively impact the aquatic environment. In this study, the solar photodegradation of propranolol (PRN) - a common blood pressure medication – was studied in aqueous solution. The data collected from each simulated natural water solution was used to determine the rates of PRN solar photodegradation with respect to humic acid or fulvic acid concentration. LC-MS/MS was used to analyze PRN and PRN degradation products. The results from this study can play a part in the ongoing effort of understanding the impacts of pharmaceuticals to the aquatic environment.

42.
Neural Circuitry Mechanisms Underlying Stroke and Alzheimer's Disease

Ashley Matunis, Emma Stacy, Yonjoo Cho, Zachary Hubbard, Kenta Abe and Takashi Sato
Department of Neuroscience, Medical University of South Carolina

The long-term goal of our research is to unravel the mechanisms underlying stroke recovery and Alzheimer’s disease and identify better treatment options. Toward this goal, our laboratory uses a mouse model system and investigates neural circuit changes using various state-of-art techniques. We perform surgeries on mice to introduce fluorescent calcium indicators in the brain. We then visualize the neural circuits inside the brain using the most advanced microscopic techniques and, at the same time, manipulate the neural circuits using optical stimulation. One of the many findings we’ve made is that the contralateral hemisphere is critical for stroke recovery. Students in this laboratory are taught the latest techniques to further stroke recovery and Alzheimer’s research.

43.
The Mechanical Properties of 2D Transition Metal Dichalcogenides

Noah Kern, Alem Teklu, Kuthirummal Narayanan, Joe Tidwell, Max Rabe and Yu Gong
Department of Physics and Astronomy, College of Charleston 

The mechanical properties of four transition metal dichalcogenides (TMDs) were studied using an atomic force microscope (AFM). Nanoindentation was performed using the AFM to generate force curves which were analyzed using the Oliver-Pharr method to find the Young's modulus of the materials. The TMDs tested were Molybdenum Disulfide (MoS₂), Rhenium Diselenide (ReSe₂), Rhenium Disulfide (ReS₂), and Tungsten Diselenide (WSe₂) which had a Young’s modulus of 71.9 GPa, 28.3 GPa, 56.3 GPa, and 40.4 GPa respectively. The results are significantly lower than the expected results which came from density functional theory (DFT) calculations. MoS₂, ReSe₂, ReS₂, and WSe₂ had percent errors of 65.7%, 80.0%, 70.4%, and 65.2% respectively.

44.
Optical 3D Imaging From Inside the Human Body: [1] design, assembly, and lab testing of a novel, miniaturized, 3D imaging scope for medical applications, and [2] combining 3D and polarization imaging techniques for improved cancer screening inside the human body

Brianna Joyner, Jenna Snead, Bailey Williamson, Stanley McAfee, Kevin Gainey, and Joe Carson
Department of Physics and Astronomy, College of Charleston

The CervImage device increases healthcare access for remote populations by providing portable 3D cervical imaging at a low cost. While testing is minimally invasive, the challenge of making the device more compact remains. A major limitation lies in the liquid lens installed in the device, which cannot be made any smaller. Dr. Carson's research group recently purchased a 2.7 mm arthroscope, which may allow the camera and liquid lens to be moved outside of the body for future testing. The goal is to determine if the arthroscope is suitable for 3D medical imaging. Additionally, by filtering out light of a given polarization direction, there is opportunity to remove unwanted glare from a surface and reveal slope. A polarization optics system and custom Python algorithm to process the images was designed to access such capabilities. These two projects worked in conjunction to improve the device's overall optical quality.

45.
Formal Analysis of Data Dependent Models in Phylogeny

Caroline Goodman and Kris Ghosh
Department of Computer Science, College of Charleston

Analyzing the complex evolution of organisms within an environment is vital to reaching a greater understanding of the world around us. This study focuses on these evolutionary relationships between varying species, individuals, and genes. Trees visualize gene sequences as they transform through generations. In this work, a formalism is created involving the construction of these phylogenetic trees under imprecision of data. Imprecise data is addressed through the implementation of stochastics. Continuous-time Markov chains (CTMC) model these phylogenetic analyses. Establishing queries and specifying properties represented by temporal logic helps to evaluate the computational feasibility of the formalism created. PRISM model checking software assesses the property specifications. Ultimately, researchers are able are able to validate models of phylogenetic systems against particular properties specified under temporal logic. 

46.
Microplastics as a Potential Vector for Ingestion of Absorbed Toxins by Invertebrate Larvae

Layne Leggett and Robert Podolsky
Department of Biology, College of Charleston

Consumption of microplastics is of concern because they can leach toxins and interfere with normal feeding. One unexplored concern is that they might also act as a vehicle for ingestion of environmental contaminants that adsorb to their surface. Because aquatic organisms are regularly exposed to both microplastics and toxins, it is essential to understand how they impact organisms independently and synergistically. We tested these possible effects using sea urchin larvae, which ingest microplastics of similar sizes to algae they normally consume. Larvae were exposed to one of several treatments: microplastic beads at low concentration, dissolved phthalates (a demonstrated toxin), beads and phthalates together, and a seawater control. The results matched our prediction: whereas beads had little effect on larval growth, phthalates in the presence of beads reduced growth more than phthalates alone. Our results suggest that microplastics could have an unappreciated indirect negative impact on organisms even at low concentrations.

47.
2021 Seasonal Changes in Nutrient Levels and Phytoplankton Community Composition of Charleston Harbor

Abigail Stephens, Nicole Schanke, Emmy Sheahan and Giacomo DiTullio
Department of Biology, College of Charleston
Grice Marine Lab

Charleston faces many challenges from climate change as a coastal city, like habitual flooding and sea level rise. These will likely cause the Charleston Harbor to be impacted by increased nutrient input from runoff, possibly changing the phytoplankton community structure and affecting the entire ecosystem. Monitoring changes in water conditions can help predict and make plans to mitigate these effects. To record the nutrient levels and phytoplankton community structure of the harbor, we partnered with local non-profit Charleston Waterkeepers to collect weekly samples from twenty sites in and around Charleston Harbor between April and October 2021. We measured nitrate and phosphate concentrations, chlorophyll a as a proxy for total phytoplankton biomass, phycocyanin and phycoerythrin as proxies for cyanobacteria biomass. HPLC methods were used to quantify phytoplankton pigments, and the CHEMTAX program related these to phytoplankton taxa. The result is a spatial and temporal description of changes in the Charleston Harbor.

48.
Simulating Cold Fronts to Determine the Effects on the Morphology of Radio Jets

Christopher Nolting and Christopher Lesoine
Department of Physics and Astronomy, College of Charleston 

Galaxy clusters are very dynamic environments which often are stirred by large scale mergers and accretion which create cold fronts. A cold front is a sharp increase in density, decrease in temperature, with no change in pressure in the background medium. These events often cause the jets emanating from radio galaxies to warp upon impact. This summer we used the wombat code to simulate the impact of different cold fronts with a radio galaxy in the intracluster medium. We were able to reliably simulate these cold front events and determined how different variations of cold fronts affected the jets that protruded from radio galaxies such as bending them, creating turbulence, and otherwise warping their morphology. This is very useful for radio astronomers who will be able to better identify cold fronts by comparing the morphology of radio galaxies with our simulated cold front events.

49.
Prototyping Microplastic Experiments for Arabidopsis thaliana

Nicole Taylor, April Bisner, Courtney Murren, Matthew Rutter and Allan Strand
Department of Biology, College of Charleston

Microplastics are becoming a serious concern with their increased presence in the environment. While many efforts are being made to evaluate the impact of these plastics in aquatic habitats, its relationship with terrestrial systems remains underappreciated. To study its effects on plants, we prototyped methods of exposing Arabidopsis thaliana plant roots to microplastics. The first approach involved polyester microfibers being integrated within agar. Seeds had their root length, lateral root number, and rosette diameter digitally measured through ImageJ. Acrylic fibers were scattered on the surface of agar for the second method. Root lengths were then measured with calipers. It was found that root lengths tended to increase in the presence of synthetic fibers.

50.
Comparing Surface and Bottom Sampling Within a Decades Long Plankton Monitoring Program

Claire K. White and Jeremy Miller
National Ocean Service

National Oceanic and Atmospheric Administration

This project will examine the differences between larval fish assemblage and abundance at two fixed depth locations within the Webhannet River Estuary in Wells, Maine. This project will look to compare the assemblage of larval species that reside deeper in the water column, located 1 meter from the bottom of the estuary. The sampling location is a well-mixed estuary which lies at the mouth of the Webhannet River. Specifically, this project will examine if surface sampling may be missing more benthic species or if concentrations of larvae are higher at deeper depths. To complete this analysis, sampling was conducted using a 500µm plankton net occuring about 4 times per month for one hour during high tide. Water temperatures and salinity are also recorded to further the analysis.

Preliminary data suggests that there is no significant difference in surface and bottom sampling concerning larval fish concentrations as well as species.

51.
The Conformation and Energy of Cyclic Sila Compounds

Sydney Gordon, Macie Gregory, Melody Pham and Gamil Guirgis
Department of Chemistry and Biochemistry, College of Charleston

There appears to be no published information available in the literature on three-membered ring compounds containing a silicon atom. Thus, in order to probe the possible stability and ring energy of three-membered silicon-containing rings, and also explore and determine the conformational stability of four-membered silicon-containing rings, we initiated a study to investigate these compounds. The project consisted of using different approaches to synthesize three- and four-membered silicon-containing rings. We were successful in producing four-membered rings with different substituents on the silicon atom. In the case of three-membered rings, the chlorosila-derivative was successfully obtained. But upon fluorination of the chlorosila-derivative, the ring was opened and a chain compound was obtained instead as indicated by nuclear magnetic resonance (NMR) spectroscopy.

52.
Impact of Molecular Weight on the Solubility Parameters of Poly(3-hexylthiophene)

Rashawn Spann and David Boucher
Department of Chemistry and Biochemistry, College of Charleston 

The solubilities of three P3HT samples of similar regioregularity (rr » 96%) butvarying molecular weight (Mn = 14 kDa, 32 KDa, and 49 KDa) are measured in 26 organic solvents. The solubility data is used to calculate the partial solubility parameters (d_D, d_P, d_H) using the functional solubility parameter (FSP) method. The results reveal a monotonic decrease in the polar and hydrogen-binding parameters, d_P and d_H, respectively, with increasing molecular weight of the polymer. Complementary computational results indicate that the observed trends are consistent with a reduction in the planarity, aromaticity, and conjugation length of the polythiophene backbone, which can be ascribed to collapse of the polymer chains due to increasingly unfavorable solvent-polymer interactions. 

53.
Privacy-preserving E-voting System Using Blockchain

Eric Pickford and Mohamed Baza
Department of Computer Science, College of Charleston

A privacy-preserving e-voting scheme was developed to support range-based score voting. Non-interactive zero-knowledge proofs of knowledge and non-interactive zero-knowledge proofs of set membership are used with a distributed ElGamal encryption to ensure the system maintains maximum ballot secrecy, self-tallying, fairness, dispute-freeness, and verifiability, all while incorporating the principles of score-voting. A minimally viable score-based e-voting system was constructed, onto which the proposed scheme can easily be added in future work. The minimally viable system was tested using Hyperledger Caliper benchmarks to measure latency, throughput, and error rate to better ascertain the feasibility of adding the security layer. It was found that the system was optimal for small to mid-sized systems, and that transactions only involving read operations performed noticeably better than those containing write operations.

54.
Mechanical Properties Chitosan Doped with Ag Nanoparticles

Logan Carabo, Alem Teklu, and Narayanan Kuthirummal
Department of Physics and Astronomy, College of Charleston

The mechanical properties of chitosan were studied using ultrasonic and AFM Imaging. ultrasound imaging is a versatile testing technique able to measure the speed of sound in an object and thus directly measure the Young's modulus of a sample, and it was found that the Young's modulus by this method was between 2.04 and 2.85 GPa. AFM Nanoindentation has also been known to be able to measure the reduced Young's modulus of samples with great accuracy, and it was found the reduced Young's modulus by AFM nanoindentation was between 9.04 and 12.61 GPa. Using AFM Nanoindentation we then formed an "image" of the Young's modulus as it varies across the surface of the sample to investigate the distribution of the nanoparticles in the sample. Furthermore, by comparing the two methods we determined the saturation point in the material to be near 0.5mg/ml. At that point adding more Ag nanoparticles no longer increases the Young's modulus of the sample.

55.
Building a Climatological Baseline for Tampa Bay, Florida 

Bernhard Lee Lindner and Alexander Garber
Department of Physics and Astronomy, College of Charleston

A climatological baseline was developed for the Tampa Bay, Fl area by using the HURDAT2 database and NOAA official hurricane tracking charts, which run from 1851 to the present. Tampa experienced a strike in 65 of the 170 years studied. The return rates for tropical storm, hurricane, and major hurricane strikes, determined by the closest point, were 1.91, 3.95, and 11.33 years, respectively. While the median TS strike date did not change much in recent years, the median hurricane strike date moved 8 days earlier when excluding data before 1984. Half of all tropical storm and hurricane strikes came from storms that approached from the Gulf of Mexico. This is most likely due to its geographical location. Finally, the average translational velocity of storms passing close to the Tampa area was higher than in other parts of the globe with the same latitude.

56.
Synthesis and Analysis of Poly(caprolactone) Polymer Systems 

Nicholas Orlando, Brooke Van Horn, Jenny Jackson and Addie Barnes
Department of Chemistry and Biochemistry, College of Charleston 

Polycaprolactone (PCL) is a material that is biocompatible, biodegradable, malleable, has a low melting point and is an ideal polymer for medical materials. The aim of this study is to effectively synthesize PCL at different weights and lengths to study it’s degradation. Synthesis of PCL monomer was conducted with the use of a tin catalyst performing a ring-opening polymerization. This was paired with techniques like MALDI to confirm properties such as end group composition, along with verification of successful polymerization through NMR. The synthesis produces polymer with high percent conversion (over 95%) and high yield (over 70%) at low degrees of polymerization, illustrating an effective synthetic route. NMR and MALDI on the smallest length polymer synthesized verified this effective control of mass and length, as well as end group composition. The use of Differential Scanning Calorimetry made it possible to establish a thermogram of the polymer to show bulk properties.

57.
An Oligonucleotide Platform: Studying tRNA Expression in Normal Mouse Tissues

Ansley Elkins and Renaud Geslain
Department of Biology, College of Charleston

Transfer RNAs (tRNAs) are highly abundant molecules responsible for the translation of cellular messenger RNAs into their corresponding proteins. It is often assumed that tRNA expression is homogenous in multicellular organisms. However, recent studies have challenged this assumption, demonstrating that tRNA levels vary among different cell types and organs. These studies suggest that cells modulate the expression of tRNA to optimize the expression of certain proteins. This project hopes to expand upon these findings, by establishing that some, if not all, tissues display unique patterns of tRNA expression. We have designed a specific oligonucleotide microarray platform that will monitor the expression of 46 tRNA species across 13 different Mus musculus tissues. We hope that the microarray profiles generated by this research will show that some if not all, tissues display distinct tRNA expression.

58.
Calibration of Rotational Velocity to CCF Width using HST/COS

Colin Kane and Laura Penny
Department of Physics and Astronomy, College of Charleston 

Projected rotational velocity (V sini) is directly correlated with the width of the cross-correlation peaks of a star's spectra. In this project, a calibration between V sini and cross-correlation function (CCF) width is going to be created to approximate the projected rotational velocity of different targets in the future. Spectra were obtained from the Hubble Space Telescope (HST) using the Cosmic Origins Spectrograph (COS) instrument for 17 different targets in the Small and Large Magellanic Clouds. The targets were O and B type systems with known V sini values. Their spectra were then cross correlated with the TLUSTY synthetic spectra and the widths of the CCFs were measured for use in a calibration. A plot of the projected rotational velocity versus the widths was created and a calibration function was fit to the data. This calibration can be used on other systems to approximate their projected rotational velocities.