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THE EFFECTS OF WINTER SHELTER CHARACTERISTICS ON OVERWINTERING DURATION, BODY MASS LOSS, AND OPHIDIOMYCES OPHIDIICOLA INFECTION LOAD IN A SOUTHEASTERN POPULATION OF TIMBER RATTLESNAKES (CROTALUS HORRIDUS)**
No full textNon-avain reptiles in temperate regions often undergo an extensive period of general inactivity during the winter season, known as brumation. At southern temperate latitudes, milder winter seasons make overwintering shelters less of a limiting resource. The numerous challenges associated with monitoring a large number of solitary individuals along with the assumption that winter is a weaker selective force in southern temperate regions as lead to a lack of information on the overwintering ecology of snake species and populations from therse areas. This data deficiency carries conservation implications, as winter in more southern latitudes still represents a vulnerable period for snakes. More than a decade of research on snake populations across eastern North America has now recognized the widespread prevalence of Ophidiomycosis ( Snake Fungal Disease ), caused by the fungal pathogen Ophidiomyces ophidiicola (Oo). Recent work has shown that Oo infection signs are greatest during the spring, shortly after the emergence from overwintering shelters. The overarching goal of this research is to explore the effects of overwintering site selection on body condition and Oo infection load in a Georgia Piedmont population of Timber Rattlesnakes (Crotalus horridus). Specifically, we will leverage the presence of communal and solitary overwintering sites occupied by rattlesnakes included in ongoing radio telemetry monitoring to quantify relationships between overwinter shelter site characters (i.e., rock pile, stream bank, stump hole) and individual vs. communal shelters on Oo infection load, body mass loss, and brumation duration. These results will inform on the proximate and ultimate factors influencing overwintering site selection, and can improve understanding of factors that might predict Oo infection liklihood and severity in C. horridus and other snakes
EFFECT OF STREAM SIZE ON DENSITY OF A HEADWATER SPECIES OF AQUATIC SNAIL (ELIMIA PROXIMA)
No full textAs an abundant scraper, the aquatic snail Elimia proxima has a significant influence on the ecology of headwater streams in the Appalachian Mountains. Because density of organisms strongly influences their roles in their environment, we tested the hypothesis that the density of E. proxima depends on stream size. We chose 13 streams of varying sizes within the Middle Fork of the Broad River System in Banks, Habersham, and Stephens counties, Georgia. We used two methods to determine snail density in each stream. In the first, we took the mean of snails counted in 6 quadrats, each measuring 1 m2, chosen as representative of different stream microhabitats. Secondly, we measured the amount of time required to count 25 snails, referred to herein as snail time). Because this second method is more time efficient, we tested for a potential correlation between the two density measures. We also took mean streambed widths of 6 representative sites along the same stream section where we counted snails in each stream. To test our hypothesis, we regressed snail time against mean streambed width, using log-transformed data. Because we ran two statistical tests on the same data, we tested for significance at a Bonferonni-adjusted alpha level of 0.025. We found a high level of correlation between density measures (r = -0.919, P \u3c 0.0001), indicating that the time-constrained count is an effective, time-efficient method of measuring density. Moreover, we found a significant dependence of snail density (snail time) on stream size (r2 = 0.549, P = 0.0091). Our data support the idea that E. proxima is a headwater species, indicating that this species exerts its greatest ecological influence in the smallest streams
PRELIMINARY ANALYSIS OF SUPPLEMENTAL FEEDING ON CAMERA TRAP CAPTURES OF SMALL MAMMALS IN CENTRAL GEORGIA
No full textAlthough it brings joy to many people, bird feeding has been shown to have potentially negative effects on local bird populations and small mammalian species. To study the differences in local occurrence of native small mammalian species around bird feeders and in more distant settings, six camera traps were placed in a rural residential area in Putnam County, Georgia. Species presence was recorded three days a week from 12:00 am Monday to 12:00 am Thursday between 11 November 2019 and 29 January 2020. We recorded 5,073 images of mammals during the 36 days: gray squirrels (4,264), eastern chipmunks (458), raccoons (113), Virginia opossums (65), domestic cats (54), white-tailed deer (36), gray foxes (35), field mice (22), armadillos (11), eastern cottontail rabbits (11), and domestic dogs (4). Pair-wise t-tests indicate a greater frequency of image-captures of gray squirrels, chipmunks, raccoons, opossums and cats near the feeders compared to the area away from the feeders. Foxes and deer were imaged more frequently in the area away from the feeders. Not only do bird feeders contribute to a higher visitation frequency in certain species such as gray squirrels and raccoons, species known to depredate bird nests, the elevated densities of birds and mammals in the area also attract more predators such as domestic/feral cats
MEASURING REPRODUCTIVE OUTPUT OF WILD-CAUGHT DWARF SEAHORSES (HIPPOCAMPUS ZOSTERAE)
No full textThe dwarf seahorse, Hippocampus zosterae, is an excellent flagship species for identifying the impacts of disturbances in seagrass ecosystems. While multiple studies have examined different laboratory settings and stressors on seahorse reproduction and juvenile seahorse growth, there has been little data collected on wild-caught reproductive quality. This study focuses on measuring brood size and offspring weights and lengths at birth of wild-caught pregnant male dwarf seahorses. Twenty pregnant males were collected in Tampa Bay and transported to Valdosta State University in June (n=10) and July (n=10). At birth, brood size was calculated, and father and offspring were weighed and photographed for body lengths to be measured using ImageJ. Across the study, dad sizes and brood sizes did not differ between the months, with an overall average of 0.2295 ± 0.0144 g for dad weights and 39.5 ± 3.9 offspring per brood (n=20). Average baby lengths, 11.16 ± 0.025 mm, did not significantly differ between months, while average baby weights were significantly higher in July at 0.0021 ± 0.0001 g than in June at 0.0016 ± 0.0001 g (n=10). Brood sizes were positively correlated to dad size. However, brood size and dad size show no relationship to average baby weights or lengths. These results allow examination of initial relationships between offspring length and weight, as well as offspring size, father size, and brood size. The data can be used to further compare field and laboratory brood qualities. Understanding the differences of seahorse reproductive qualities between these two settings will allow for better interpretation of lab-bred juvenile studies. Reproductive rates of pregnant males collected in the field will better inform predictions of recruitment patterns of wild populations and allow detections of the effects of potential environmental disturbances or habitat loss of seahorses
CLONING OF AN ALGAL AQUAPORIN GENE
No full textAquaporins are proteins that selectively transport water across membranes. The current work is part of a larger research project to explore the use of aquaporins in a biomimetic film for the desalination of water. The bioinformatics program BLAST was used to find an aquaporin gene in the micro algae, Trebouxia. This gene was chosen because of its high sequence similarity to a proposed aquaporin gene in a salt water sea lettuce, Ulva mutabilis. The hypothesis is that aquaporin proteins from salt water organisms may be better choices for the desalination of water than from other species. The Ulva m. proposed aquaporin sequence was not used directly due to its being less characterized than the Trebouxia gene from the NCBI database. The Trebouxia gene was successfully cloned into E. coli and experiments are underway to clone into yeast. As a eukaryote, the yeast may be a better expression vector for the aquaporin. Over expression of aquaporin in E. coli is known to be toxic to the host. The goal is to produce aquaporin in sufficient amounts to use to make the desalination membranes. The gene identification and progress to express the algal aquaporin will be discussed both qualitatively and quantitatively
AN OPTIMIZATION OF TIME IN THE BROMINATION OF VANILLIN REACTION**
No full textThe bromination of aromatic rings is a common and useful reaction in classroom and industry settings. One example of this reaction, that organic chemistry students learn, is the electrophilic aromatic substitution of vanillin to produce bromovanillin. Vanillin contains multiple substituents that have differing directing properties so it is an ideal reagent for regio-chemistry analysis. This particular reaction is also practical because it can be run in a variety of ways and the reagents are fairly inexpensive. In order to avoid the use of elemental bromine, bromine was formed in situ with potassium bromate in the presence of acetic acid. The goal of this project was to optimize the time of this bromination reaction while still maintaining product purity and yield. The reaction was run for 5, 15, 25, 35, and 45 minutes at a time. Each reaction product was then assessed for percent yield and product purity. The results will be presented and discussed
SYNTHESIS AND BIOLOGICAL ACTIVITY OF N-SUBSTITUTED-BENZOTHIAZOLIUM SALTS UPON APPLICATION WITH ALS CELLS AND THE EFFECTS OF THE TDP-43 PROTEIN**
No full textAmyotrophic lateral sclerosis (ALS) is a progressive neurodegenerative disease that affects nerve cells in the brain and spinal cord. Motor neurons run from the brain to the muscles and impact voluntary muscle action where patients can lose the ability to speak, eat, move, and breathe. Riluzole is the only FDA-approved oral drug for ALS that has been shown to have little to no effects on the treatment and is a known benzothiazole compound. Using a series of substituted benzothiazoles that have been synthesized, this study will test these compounds on U2OS, SH-SY5Y, and HEK293T cells with overexpressed TDP-43 protein aggregates and their effects with each other. TDP-43 is a protein that is commonly found within the nervous system of sporadic ALS patients, that causes rapid pathogenic activities. During this process the cells will be analyzed for rate of growth in hopes of creating a cell model that will demonstrate an alternative therapeutic option for treating ALS. In this proposed project, I would like to use my organic chemistry skills to generate and identify new effective organic compounds to treat ALS
EXPERIMENTAL DEMONSTRATION OF DIELECTRIC CONSTANT ENHANCEMENT WITH METAL PATCHES
No full textAccording to previous research it was shown by simulation that dielectric constant of a material could be enhanced by adding metal patterns on it. In this project, experiments were conducted to demonstrate the enhancement of dielectric constant with circular metal patches of various diameter printed on the host material. Experimental results showed that material dielectric constant increased with the increase in metal patch diameter and theoretically any value of dielectric constant could be achieved by adjusting the size of the metal patches
EXPERIMENTAL DESIGN AND COMPARATIVE ANALYSIS OF DESALINATION OF HYPERSALINE BRINES USING TEMPERATURE SWING SOLVENT EXTRACTION
No full textWith the increase in world populations, sourcing purified, potable water continues to become a challenge. Hypersaline brines are readily available and, when desalinated, could provide a source for clean drinking water. Current desalination techniques include evaporative distillation and reverse osmosis, but high energy consumption and an inability to efficiently process high total dissolved solids levels, make them less attractive options. Temperature swing solvent extraction provides a promising alternative method characterized by membrane-less, low-energy, and cost-effective desalination. The technique utilizes temperature swing and a low-polarity solvent with temperature-dependent water solubility. Amines have properties desirable for solvent as they have both of hydrophilic and hydrophobic moieties and the water solubility in the amines varies at high and low temperatures. This study aimed at designing the experiments to evaluate the desalination effectiveness of amines and optimize the solvent-specific extraction conditions. The main parameters included the calculation basis (mole, volume, and mass), solvents with varying degree of substitution (secondary versus tertiary) and different hydrophobicity (chain length), hypersalinity of the feed, and the schemes of temperature swing. The effects of varying substituents and different concentrations of salts on the final volume of the product water were examined. In addition, the quality of the desalination product was evaluated for residual amine and salt concentrations as well as the parameters. Secondary amines extracted the largest quantities of product water from both 1M and 4M brines, compared to tertiary amines. Molar basis comparison accounted for the varying densities of amines and thereby was most relevant when comparing the solvent/feed ratio. The optimal conditions for solvent-feed specific desalination and the cost analysis of corresponding temperature swing processes will provide the stakeholders including academic research groups, local and federal governments, and industries with both the scientific and practical information for feasible and reliable scale-up applications
DESIGN OF A HIGH VACUUM CHAMBER AND MICROWAVE FABRY-PEROT CAVITY RESONATOR USING TORISPHERICAL CAP MIRROR
No full textA Balle-Flygare type cavity Fourier transform microwave (FTMW) sprectrometer is built by a Fabry-Perot cavity resonator in a high vacuum chamber. A torispherical cap will be used as both a mirror of the Fabry-Perot resonator and the tank head to close the vacuum chamber. This design can cut the costs of a vacuum system significantly. The effective dish reflector diameter, volume, and focus length of various torispherical domes are evaluated and discussed, including, but not limited to, DIN 28011, ASME standard, ASME high crowns (80/10, 80/6, and 90/8), and the noncoded tank heads. Gold plating will be performed on the dish surfaces to upgrade the conductivity, enhance the microwave reflectivity, and improve the corrosion resistance