Staminodes are infertile stamens that have evolved numerous times in flowering plants and exhibit a vast array of forms and functions. Variation in staminodes suggests that numerous evolutionary processes underlie their origins, but to understand their how and why they evolved, comparative studies are needed in groups of closely related species. Identifying structures as staminodes is not always straightforward and sometimes requires corroborating phylogenetic and developmental evidence. Staminodial structures in Paronychia (Caryophyllaceae), for example, vary in shape and size and have been referred to as both petals and staminodes, rendering their homology uncertain. The development of staminodes was compared across species of Paronychia. We tested the hypotheses that structures were either petals or staminodes and by evaluating floral development of fourteen species with scanning electron and light microscopy and conducted ancestral state estimations across phylogenies to infer when staminodes evolved. Staminodes developed between the stamen whorl and carpel, indicating a true staminodial origin. Staminodes evolved prior to the origin of Paronychia and were lost at least three times. Staminodes in Paronychia began as vestigial stamens following the loss of anthers and were either highly reduced, remained vestigial, or coopted, which we term the vestigial intermediate hypothesis. Our results illustrate a dynamic history of staminodial evolution in Paronychia and that selection on the function of staminodes can differ across closely related species.

Microplastics are plastic particles smaller than 5 mm. Various pollution routes have led to abundant microplastics in marine environments. To better understand the severity of microplastic contamination, it is important to measure for microplastics in all marine habitats and organisms; yet, data describing algal capture of microplastics are scarce. The purpose of our study was to test algal filament length using mimics to determine whether filament length results in different amounts of microplastics being captured. We hypothesized that more microplastic would be trapped in longer than shorter filaments. This was tested using weathered microplastic polyester fibers and styrofoam in two algal mimic treatments: pipe cleaners with 1.0 cm and 0.5 cm filament lengths. We observed that full length mimics trapped 23.3% more fibers, which was significantly greater than half length mimics. Preliminary results for styrofoam indicate a similar trend as the fibers, supporting our hypothesis that filament length influences microplastic capture. If future field experiments support these results, then this implies that longer, palatable algal filaments may introduce greater amounts of microplastic into the food web. Ultimately, determining how microplastics enter the food web will advance our understanding of microplastic concentrations in animals, including the human diet.

Epigenetics is the study of phenomenon that change gene expression without changing DNA sequence. DNA methylation is the addition of a methyl group to the base cytosine. This is locally inhibitory to binding of regulatory proteins and is used to regulate gene expression. One way we know animals use DNA methylation is in their response to environmental stress. One common environmental stressor is human made dams that are used to alter the flow of rivers. Channel catfish are a common river species that may be affected by this stressor. Rivers in Illinois have been altered by dams. These dams change the habit, which may cause physiological stress to the fish. My research question is, in these stressful environments, do channel catfish alter their DNA methylation? If so, they could be using DNA methylation to fine-tune their gene expression to change their phenotypes in response to the stress. I used epiRADseq to measure DNA in channel catfish from multiple locations, some interrupted by dams. I will test patterns of DNA methylation to see if there are detectible differences associated with the presence of dams. I will test the statistical hypothesis that there are no significant differences in DNA methylation among individuals predicted by the presence of dams.

Eastern equine encephalitis virus (EEEV) is a togavirus transmitted by mosquitoes that infects a variety of vertebrates, but notably is known to cause significant mortality in horses and humans (Calisher 1994, Bingham et al. 2012). It is found in North, Central and South America; in North America it is especially found in Georgia and Florida. Culex erraticus is one of the most prevalent species in many areas where EEEV cases are reported, including the southeastern United States (Cupp et al. 2003, Cohen et al. 2009). EEEV is considered to be one of the deadliest arboviruses transmitted by mosquitoes to humans with a mortality rate of 33% (CDC 2015). Culex erraticus exhibits high potential of acting as a vector of EEEV due to its nonselective feeding patterns and large presence in areas known to support the virus. Snakes could contribute a large part in how the virus passes through the winter as they can still remain infected by the virus during this period (Graham et al. 2012, Bingham et al. 2012). The objective of this study is to conclude whether or not Culex erraticus shows any significant behavioral response in a dual choice olfactometer to the odors produced by the skins of different species of snakes, including but not limited to copperheads (Agkistrodon contortrix) and water moccasins (Agkistrodon piscivorus). Culex erraticus mosquitoes were collected in Bulloch County, Georgia, and bioassays are currently being performed to analyze the response of the mosquitoes to each snakeskin alone and then comparing the response across all snake species analyzed.

Through the behavior of past data, we use Game Theory to model our findings, predict decisions made by businesses, and understand what scenarios will produce a stable stock market. In particular, we will provide a thorough analysis of the stock market behavior between the three leading competitors in technology: Apple, Microsoft, and Google.

To begin, we will use the Nasdaq website, a detailed online record of the stock market, to record the daily price of stock and share volume for each company. We will analyze the trend of the data through common statistical models. The findings from this analysis will be used to construct our Game Theory model, which we analyze through Nash equilibriums.

As a result, we should be able to evaluate the stability of the stock market and discuss the relationships between our companies. More specifically, we expect to find the impact changes in the stock market have on each business and predict the behavior, or the “best next move,” they should have.

Poly(carboxylate), a water-soluble polymer, has many applications, one of which is as a superabsorbent material commonly found in products like diapers and feminine hygiene products. These materials are non-biodegradable and alternatives are necessary to mitigate their accumulation in the environment. Poly(aspartic acid) (PAA) is a safe, biodegradable alternative that can be broken down by three different enzymes. This project focuses on PAAH-2, one of the PAA degrading enzymes, and aims to characterize the catalytic active site of the hydrolase. The DNA sequence for the protein was purchased and then expressed using E. coli cells. The protein was purified using an immobilized metal affinity column and the purity was assessed using SDS-PAGE. Initial crystallization leads were identified by the Hauptmann-Woodward Institute (HWI) and PAAH-2 crystallization experiments were optimized using the conditions initially seen by HWI. Here we will present the structure of PAAH-2 predicted from the crystal structure as well as the activity assays used to characterize the protein.

Nanoclays are microscopic clays that are comprised of layered nanoparticle aluminosilicates that are naturally arranged in several morphologies. Halloysite nanotubes (HNT) are hollow, double layered tubes, bentonite (BNT) clays are trapezoidal platelets, and nanosilica or silica dioxide (SiO2) are spherical in shape. These nanoclays were chosen for sustainable purposes as they are naturally derived and for economical purposes because of their cheap commercial availability. In this study the nanoclays are functionalized with an epoxy organosilane group through reflux conditions at 120 °C for 24 hours. The pristine and functionalized nanoclays were extensively characterized with infrared (IR) spectroscopy, scanning electron microscope (SEM), energy dispersive x-ray spectroscopy (EDS), powder x-ray diffraction (PXRD), thermogravimetric analysis (TGA) to verify the loading of organosilane groups. The functionalized form of these morphologically different nanocalys can be utilized in a variety of enhancements for composite materials such as improved thermal resistance, mechanical strength, and increased fracture toughness.

Wyeomyia smithii, commonly called pitcher-plant mosquitoes, are distributed throughout the eastern portion of North America following the distribution of Sarracenia purpurea, or purple pitcher plant. Wyeomyia smithii is an interesting species of mosquito because there are populations that consist of only blood-feeding mosquitoes (Florida), some with only non-blood-feeding mosquitoes (North Carolina), and populations that consist of both (Georgia). This study will focus on finding these genetic differences between Wyeomyia smithii and other species of blood-feeding mosquitoes. The genes from Wyeomyia smithii will be compared to similar genes in other species of mosquitoes to see if there are distinct differences in the proteins the genes code for. This comparison will indicate if the blood-feeding behavior is simply based on the level of gene expression, or if there is a genetic variation that influences the behavioral change.

This research is significant because it is important to see how exactly mosquitoes are evolving as the climate is evolving. If Wyeomyia smithii has shifted more towards biting as the climate has changed, then other species of mosquitoes may also be evolving in this direction. This research can be further applied to see how all mosquito populations are evolving throughout the world. Blood-borne illnesses that use mosquitoes as vectors kill millions of people every year and this research can be applied to populations of mosquitoes that do spread these deadly diseases.

Sound travels at different speeds through different materials; this speed is typically calculated using the material’s stiffness and density. In this project we will be using a field-programmable gate array (FPGA) along with geophones and GPS for timing to determine the speed of sound in steel to compare this to the values found using the material’s properties.

Fertilizer runoff is a major cause of harmful algal blooms. This runoff can be high in nitrogen content which is one of the major metabolites of plants. Nitrogen is usable by plants after it undergoes nitrogen-fixation by microbes. As an effort to reduce the effects of algal blooms, cover crops are a major area of research. Cover crops can be planted with desired crops and along waterways in an attempt to reduce the concentration of the causative agents of these blooms. Two aquatic plants found in coastal Georgia were used for this study. Compared to Vallisneria spiralis, we hypothesized that Eichhornia crassipes would be the most efficient at taking up excess nitrogen from fertilizer due to its extensive root system. Aquatic plants were favored over terrestrial plants for this study in terms of saving media and space. Additionally, it is thought that these aquatic plants may be a more direct method of rapid nitrogen uptake.

Pharmaceuticals, including hormones and antibiotics, are considered contaminants due to their widespread use and release into the environment. Synthetic estrogen used in oral contraceptives (17α-ethinylestradiol), is present in freshwater and marine systems, but with relatively unknown effects on the organisms that live there. Ethinylestradiol (EE2) accumulates in waterlogged soil (sediment) with potential to harm sediment-dwelling animals. For example, fiddler crabs (Uca pugilator) are vital members of salt marsh communities. Their burrowing adds oxygen to sediments and cycles nutrients, and they are an important food resource. Male fiddler crabs are territorial, aggressively defending their burrows from intruders. Given that synthetic estrogen reduces aggression in other aquatic organisms, I hypothesized that EE2 affects male fiddler crab aggression. Male crabs exposed to EE2 were expected to retreat from threats instead of attacking more often than control animals. Male aggression was measured as responses to threats (fleeing, attacking, no response) after exposure to sediment without (control) or with added EE2 (0.5 mg L -1 ). There was a trend toward EE2 treated crabs fleeing from a fight more often than control crabs, but none of the other responses differed between treatments. The lack of significant response was likely due to the measured concentration of EE2 in the treated sediment being two orders of magnitude less than the calculated concentration. Therefore, while these findings indicate the possibility that EE2-exposed males may have difficulty protecting themselves, their burrows, or their mate from predators, higher EE2 concentrations with larger sample sizes need to be tested for verification.

Marsh dieback is a periodic and sudden event where large regions of salt marsh grass thin in coverage or die completely. The causes of dieback are currently uncertain although it has been linked to hyper-salinity, sea-level rise, anthropogenic factors, drought, and groundwater hypoxia. The state of Georgia has approximately 619 km2 of coastal marshlands in and around its fourteen barrier islands. Marsh dieback affects the health of these salt marshes, which are one of the most productive ecosystems in the world and provide many benefits to the surrounding environment and community. One of the questions this research aims to answer, is if there is a difference between groundwater in areas of marsh dieback and areas for healthy marsh. This study is measuring radium concentration, radon concentration, water temperature, dissolved oxygen (DO), specific conductivity, salinity, and calculating groundwater flushing time in an attempt to discover if a link between groundwater and marsh vegetation health exists and if their relationship can be used to predict areas of marsh dieback. Since groundwater is the primary supplier of nutrients to marsh vegetation, the behavior of the groundwater has a large effect on plant health. This study will contribute to a longitudinal research at the study site, further knowledge in the field, and can be used in future marsh preservation efforts.

Fragile X syndrome (FXS) is the most common single genetic cause of autism. In FXS, the Fmr1 gene is transcriptionally silenced preventing the formation of fragile X mental retardation protein (FMRP). Individuals with FXS show hypersensitivity to auditory stimuli. Fmr1 knockout mice replicate many symptoms seen in individuals with FXS including heightened auditory responsiveness. Previous studies using Fmr1 knockout mice demonstrate imbalances in inhibitory and excitatory inputs within auditory brain stem nuclei as well as altered astrocyte expression. In particular, the lateral superior olivary nucleus (LSO) shows an imbalance in synaptic inputs and an increased number of astrocytes. Astrocyte dysfunction may be impactful because astrocytes regulate synaptic development and synaptic pruning. Astrocytes also act as an intermediary between neurons and blood vessels in the brain. The current study was conducted to determine if the increase in astrocytes is associated with excessive vascularization within the LSO. Blood vessels in brain sections from wild-type and Fmr1 knockout mice were labeled using isolectin, and fluorescent imaging was performed. ImageJ software will be used to determine the density of blood vessels in wild type vs knockout mice LSO. It is expected that Fmr1 knockout mice will exhibit a higher density of blood vessels.

Zebrafish are gaining popularity as a model organism for the study of neurodegenerative diseases such as Alzheimer’s disease. However, shortcomings exist in current knowledge regarding the function of muscarinic acetylcholine receptors (mAChRs), a class of G-protein-coupled receptor, in zebrafish brain. Five types of mAChRs exist in the brains of mammals and zebrafish that contribute to cognitive processes. Extracellular signal-regulated kinase (ERK) is a protein required for learning and memory, and ERK activity is stimulated by phosphorylation downstream of mAChR activation. ERK dysfunction provides a potential link between mAChRs and disease pathogenesis. Previously, it has been shown that stimulation of mAChRs using the non-specific mAChR agonist oxo-m induces ERK phosphorylation in the zebrafish brain. The objective of the current study is to determine if the M1 subtype of mAChRs underlies the increase in phospho-ERK induced by oxo-m in the telencephalon, a structure required for learning and memory, in zebrafish. Zebrafish brains were extracted before treatment ex-vivo in oxygenated artificial cerebrospinal fluid containing oxo-m and pirenzepine, a M1 selective inhibitor. Following treatment, Western Blots were performed to determine the amount of phospho-ERK present in the telencephalon. The findings from this study will contribute to understanding the M1 receptor function in zebrafish.