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Investigating The Response Of The Eastern Oyster (Crassostrea Virginica) To Low Dissolved Oxygen Conditions, Abiola Obafemi

Master's Theses

The Eastern oyster (Crassostrea virginica) requires dissolved oxygen (DO) of about 4 mg/L to support proper physiological function. Hypoxia and/or microxia occur when DO decreases to ≤ 2 mg/L. Salinity and temperature changes resulting from large-scale freshwater influx have been identified as key factors influencing the oyster populations in the Mississippi Sound. It is important to investigate the impacts of DO conditions on oyster mortality, biomass, size, and condition during these freshening events. Under controlled laboratory experiments, this thesis investigated 1) the response of oysters to microxic, hypoxic, and normoxic conditions 2) the response of oysters to combined hypoxia and …

Effects Of Increasing Cycling Cadence On Post-Cycling Gait Velocity: An Experimental Study, Nitu Lama

Master's Theses

Previous research has shown that increasing cycling cadence, rather than the workrate, can result in improved post-cycling gait velocity. However, the specific threshold of cycling cadence required to bring about clinically meaningful changes in gait velocity remains unknown. To address this knowledge gap, our study aimed to determine the minimum incremental increase in cycling cadence that would lead to a significant improvement in post-cycling gait velocity. A total of 42 young adults participated in our study and were randomly assigned to one of three groups: TEN, TWENTY, and THIRTY. Each group was assigned to cycle at a cadence at the …

Biometric Assessment Of Spotted Seatrout (Cynoscion Nebulosus) From Recreational And Commercial Fisheries In Mississippi, Usa, Nimah Folake Osho-Abdulgafar

Master's Theses

Quantitative stock assessments for Mississippi’s Spotted Seatrout use length-, age-, and sex-composition data from fishery-independent sources as proxies to estimate biostatistical characteristics of fisheries harvests due to lack of sector-specific data. In Chapter 2, I examined the age, length, and sex composition of Spotted Seatrout from three fishery-dependent sectors. Between April and December 2023, I collected 210 fish (n = 19, 124, and 67 from private, charter, and commercial sectors, respectively). The length ranged between 373-535mm, 285-523mm, and 345-568mm TL, with mean ± SD lengths of 453 ± 51mm, 393 ± 57mm, and 442 ± 53mm TL, respectively. Age ranged …

Investigation Of The Microbiome Of A Recirculating Aquaculture System (Ras) For Crassostrea Virginica Larvae, Isabelle Townsend

Master's Theses

Recirculating Aquaculture Systems (RAS) offer control over physicochemical and biological factors impacting aquaculture success. One understudied facet of RASs is the water microbiome. Oyster larval microbiomes are shaped by their aquatic microbiomes. Understanding the dynamics of and the factors shaping RAS microbiome may provide insights to how the microbiome can be a tool for optimizing larval production. This study’s goals were to investigate the microbiome stability of a RAS rearing oyster larvae across time and space, determine impacts of larval presence on the microbiome, and examine connections between larvae production outcomes and microbiome stability. Water samples were collected weekly from …

Impact Of Thermal-Hydric Stress Of Physiological Performance And Mating Behavior Of Fiddler Crabs, Talene G. Yeghissian

Dissertations

Fiddler crabs live on the edge of their thermal tolerance limits, balancing the need to thermoregulate with the need to mate. Previous research suggests that increased temperature reduces fiddler crab surface activity time, thus decreasing mating opportunities, throughout the range species with greatest impacts to low latitude populations. The less studied missed mating opportunities associated with behavioral compensation for thermal stress are crucial to understanding species vulnerability to climate change. In this dissertation, I describe a combination of experimental and observational approaches in the field and in the laboratory to investigate the physiological and behavioral responses of fiddler crabs to …

Salinity Tolerance Of Flowering Rush, Butomus Umbellatus, Andrew Coomes

Master's Theses

Flowering rush is an invasive aquatic plant in North America that causes deleterious effects to native ecosystems. There are two cytotypes, a triploid and diploid, and multiple genotypes contained within the diploid cytotype currently established in the U.S. Despite its presence in river drainages connected to estuarine areas, documentation on the salinity tolerance of flowering rush is scarce. Currently, information is limited to anecdotal reports suggesting intolerance to saline conditions. A better understanding of the osmotic tolerance of this species is essential to providing insight into its’ invasive range and better inform management efforts. These studies investigated vegetative propagule germination …

Uncovering Novel Small Regulatory Rna In Protostome, Sweta Khanal

Dissertations

Small RNAs play pivotal roles in post-transcriptional gene regulation across diverse phylum of protostomes. In this study, we investigate the functional significance of atypical miRNAs, mirtron miR-1017 in Drosophila. Through ectopic expression in neuronal cells, we demonstrate that miR-1017 extends lifespan by targeting its host transcript, acetylcholine receptor Dα2, and influencing its splicing. This novel trans-regulatory function suggests a mechanism for mirtron evolution, highlighting the interplay between splicing and post-transcriptional regulation. Additionally, we profile small RNA populations in the polychaete developmental model Capitella teleta, shedding light on the small RNA landscape in annelid worms. Our analysis reveals a rich …

The Assessment Of Autonomic Function In Young Adults With An Elevated Risk Of Metabolic Syndrome, Ta'quoris Newsome

Master's Theses

Metabolic syndrome (MetS) is a complex medical condition defined by the co-occurrence of multiple cardiometabolic risk factors. Despite the well-defined profile of autonomic function in individuals with MetS, autonomic function in those with an elevated risk of developing MetS remains unclear. Our study aimed to shed light on the progression of cardiometabolic disease and its impact on autonomic function. To investigate, twenty participants, ten of whom were classified as having an elevated risk of developing MetS based on identification of risk factors using NCEP ATP III criteria, completed a two-visit study protocol. In the second visit, spontaneous cardiovagal baroreflex sensitivity …

Molecular Characterization Of Stress Response In Western Honey Bee (Apis Mellifera), Faizan Tahir

Master's Theses

Honey bees are incredibly important for the reproduction of flowering plants and the sustainability of agricultural ecosystems. However, they face various stressors such as pesticides, pathogens, habitat loss, and climate change. Extensive research has been conducted to understand how bees respond to these stressors. Scientists have discovered that honey bees exhibit complex physiological and behavioral responses to stress at individual and colony levels. Stress can have a significant impact on their immune function, foraging behavior, and reproductive success (Decourtye et al., 2010). Understanding bee responses to stress is crucial for several reasons. Firstly, honey bees are vital for the pollination …

Ncaa Di Student-Athletes’ Understanding Of And Attitudes Toward Mental Performance Services, Allison Rudisill

Honors Theses

Mental performance services are designed to assist student-athletes with psychological challenges affiliated with performance (McHenry et al., 2022). Currently, only 65 NCAA DI athletic institutions employ a psychological provider, with only 23.2% of those being mental performance consultants (MPCs; Jones et al., 2022). As student athletes are aware of the mental demand of sport (Bemiller & Wrisberg, 2011) and the NCAA begins to bring awareness to the importance of the mental well-being of the athlete (NCAA Transformational Committee, 2023), it is important to understand student athletes’ attitudes toward these services. Therefore, the purpose of this study was to learn about …

The Impact Of Differing Instability Devices On Postural Sway Parameters, Kacey Wallace

Honors Theses

Single-limb balance training is an integral part of preventing and rehabilitating lower extremity injuries. Practitioners use instability devices to provide a progressive overload to an individual during single-limb balance training sessions. Previous investigations have shown that when using instability devices, differences may or may not exist in postural sway parameters during use depending on the specific devices being assessed. Thus, this investigation sought to examine differences between a commonly used foam pad and a novel instability device (block) in measures of postural sway.

This experiment consisted of 22 healthy individuals with no history of lower extremity injury and neurological disorders. …

Genetic Analysis Of Global Sawfish Populations, Kylie Faulkner

Honors Theses

Family Pristidae contains five of the most critically endangered elasmobranch species: Anoxypristis cuspidata, Pristis pristis, Pristis pectinata, Pristis zijsron, and Pristis clavata. The species of this family have suffered drastic population declines and range reductions due to historic patterns of overexploitation, accidental entanglement, and habitat disruption. The conservation of this taxa has been historically complicated by taxonomic uncertainty, as similar morphologies across species make them exceedingly difficult to identify. A morphological and genetic comparison of sawfish specimens collected globally was conducted in 2013, which supported a reduction in the number of described species from seven to …

The Effects Of Prescribed Fire On Microbial Biomass Abundance In Longleaf Pine Ecosystems, Sarah K. Borne

Honors Theses

One of the most diverse ecosystems, longleaf pine (Pinus palustris) habitats comprise only a small fraction of the habitat they once spanned in the Gulf Coastal Plain Region of the Southeastern United States. To preserve longleaf pine ecosystems, proper prescribed burning techniques and ecosystem management are essential for preventing high intensity wildfires and increasing species diversity. Little is known about the effects of prescribed fires on carbon levels, nitrogen levels, and microbial biomass in longleaf pine forests. These components are crucial for determining how well burned areas are recovering at a microbial level compared to unburned areas. The …

Effects Of Dissolved Oxygen And Ph On Eastern Oyster (Crassostrea Virginica) Growth, Karina D. Ledezma

Honors Theses

Coastal ecosystems, known for their abundant natural resources and role in environmental processes, are facing challenges posed by climate change, pollution and anthropogenic activities. Among these challenges is the expansion of hypoxic zones, characterized by low dissolved oxygen (DO) levels, which poses a significant threat to benthic organisms and oyster fisheries. This research investigates the interaction between hypoxia and pH dynamics, intensified by freshwater input, and the biomineralization of Eastern oysters (Crassostrea virginica). To explore these dynamics, experimental trials were conducted in 24 tanks, simulating normoxic, hypoxic, and fresh hypoxic conditions, to assess the impact of hypoxia on …

Effects Of Cogongrass Invasion On Soil Biota And Nutrient Loads In A Longleaf Pine Savanna, Jordan Werneth

Honors Theses

The longleaf pine (Pinus palustris) ecosystem, characterized by its namesake pine species and diverse community of understory vegetation, is a hotspot of biodiversity in the southeastern United States. The longleaf pine savanna is differentiated from other longleaf systems through the combination its unique assemblage of herbaceous understory vegetation, wide-open canopy, and distinct hydrogeological composition. Longleaf pine ecosystems, including savannas, are facing significant decline from their historic range due to anthropogenic interference including fire suppression, habitat fragmentation, deforestation, and the introduction of invasive species such as cogongrass (Imperita cylindrica).

Cogongrass, a nonnative grass species introduced to the …

The Effects That Dietary Intake And Cardiorespiratory Fitness Has On Insulin Resistance In Adults, Trinady Moore

Honors Theses

Insulin resistance can impair bodily responses to insulin and the uptake of glucose within the human body. This imparity has many consequences and can more commonly cause Type II Diabetes.¹ This study focuses on how different lifestyle modifications can be used to combat the sensitivity to insulin within the body. The sample included forty-one adults whose ages varied from 18 to 35 years old. The participants completed a VO2max test, blood glucose test, and a 31- item food frequency survey. These tests and survey questions revealed the correction between the participants’ age, blood glucose levels, VO2max score, and diet …

Mate Choice Between Two Species Of Topminnows From Dissimilar Hybrid Zones, Chloe Davis

Honors Theses

Understanding the origins of reproductive isolation between closely related species is foundational to evolutionary and ecological research. Recent reviews have documented contemporary hybridization between a large portion of species. A greater knowledge of reproductive isolation and its components are vital to expanding conservation efforts for threats such as those to species persistence and community processes. However, there is a lack of clear understanding of how isolating mechanisms evolve throughout many systems where hybridization is prominent. Individuals within the Fundulus notatus species complex (F. notatus, F. olivaceus, and F. euryzonus) readily hybridize at many contact zones replicated throughout their …

Understanding The Functional Role Of Lone Star Tick (Amblyomma Americanum) Threonyl-Trna Synthetase In Reproductive Fitness, Anza Ali

Honors Theses

Introduction: Transfer RNA synthetases are a family of enzymes that catalyze the addition of amino acids to their corresponding transfer RNAs (tRNAs) and play an essential role in protein synthesis. Ticks are obligate hematophagous ectoparasites that rely on prolonged feeding periods to complete their life cycle on a vertebrate host. Tick tRNA synthetases help the tick in continuous protein synthesis for efficient blood feeding and reproductive fitness, thus presenting a potential target for developing new tick control strategies. Studies have been conducted assessing the functionality of different tRNA synthetases such as Valine-tRNA synthetase, Asparagine-tRNA synthetase, Lysine-tRNA synthetase, and Leucine-tRNA synthetase …

Biophysical Factors Affecting Habitat Suitability For Crassostrea Virginica, Jason D. Tilley

Dissertations

Oyster reefs provide a variety of important ecosystem services. However, the mortality rate of eastern oyster, Crassostrea virginica, the dominant species that produces oyster reefs in the northern Gulf of Mexico, is increasing at an alarming rate due to a variety of abiotic and biological factors. I examined how biophysical factors, including the less-studied fatty acid profiles of the suspended particulate matter on which oysters feed, influenced morphometric condition of C. virginica.

I sampled suspended particulate matter (SPM) and oysters in-situ in the western Mississippi Sound, which historically supported the majority of oyster production in Mississippi waters. Sampling …

How Sewage Pollution Affects Distribution And Life History Traits Of The Southern House Mosquito, Culex Quinquefasciatus, Catherine Dean Bermond

Master's Theses

Eutrophication from wastewater can cause fluxes of nutrients like and carbon and nitrogen in urban waters. One source of nitrogen in freshwater is from untreated sewage discharging from septic tanks. This causes a variety of environmental issues including harmful algal blooms, harming natural predators, and increased production of mosquitoes. Culex quinquefasciatus is the vector of West Nile Virus in St. Tammany Parish, Louisiana. St. Tammany Parish has over 600 miles of septic ditches, which receive effluent directly from aerated treatment units. Culex quinquefasciatus oviposit in polluted waters, and larvae perform well in water with high levels of decomposing organic matter. …

Evaluating Habitat Use By Nekton In Widgeon Grass (Ruppia Maritima), Shoal Grass (Halodule Wrightii), And Unvegetated Bottom Habitats In The Grand Bay National Estuarine Research Reserve, Jessica Woodall

Master's Theses

Seagrass beds support high biodiversity and animal abundance, serve as feeding grounds for a variety of animals, offer shelter from predation, and act as a nursery habitat for juveniles. The species composition of seagrass beds can impact their use as habitat by animals. Two common species of seagrass in the Gulf of Mexico are Ruppia maritima (widgeon grass) and Halodule wrightii (shoal grass). The shallow coastal waters of the Grand Bay National Estuarine Research Reserve (NERR) support both species, but the use of each seagrass as habitat by nekton is poorly understood, which can limit management decision-making. Nekton communities were …

Sensing The Rhizosphere: Microbial Transcriptome Responses To Root Exudates And Redox-Active Metabolites, Ankita Bhattacharyya

Dissertations

The term “rhizosphere” describes the dynamic interface between plant roots and soil influenced by root exudates. It is a hotspot of microbial activity, plant-microbe, and microbe-microbe interactions. Distinct variations in bacterial diversity are thought to be driven by plant root exudates. However, the molecular details of these processes still remain unclear.

I addressed this gap by focusing on two strains, Pseudomonas synxantha 2-79 and Burkholderia lata 383, representing diverse groups of Gammaproteobacteria comprised of species with environmental, agricultural, and medical significance. In the first part of this project, we used a combination of metabolomics and RNA-seq to characterize transcriptome responses …

Characterization And Estimation Of Musculoskeletal Pain Using Machine Learning, Boluwatife Faremi

Master's Theses

Traditional scales utilized for recording pain are known to be highly subjective and biased due to inaccuracies in recollecting actual pain intensities. As a result, machine learning (ML) models that are trained using these scores as ground truth are reported to have low performance for objective pain classification because of the huge disparity between what was felt in moments of pain and the scores recorded afterward.

In the present study, two devices were designed for gathering real-time, continuous in-session subjective pain scores and the recording of the autonomic nervous system (ANS) altered endodermal (EDA) activity. 24 participants were recruited to …

Annotation Of Non-Model Species’ Genomes, Taiya Jarva

Master's Theses

The innovations in high throughput sequencing technologies in recent decades has allowed unprecedented examination and characterization of the genetic make-up of both model and non-model species, which has led to a surge in the use of genomics in fields which were previously considered unfeasible. These advances have greatly expanded the realm of possibilities in the fields of ecology and conservation. It is now possible to the identification of large cohorts of genetic markers, including single nucleotide polymorphisms (SNPs) and larger structural variants, as well as signatures of selection and local adaptation. Markers can be used to identify species, define population …

Solving The Cable Equation, A Second-Order Time Dependent Pde For Non-Ideal Cables With Action Potentials In The Mammalian Brain Using Kss Methods, Nirmohi Charbe

Master's Theses

In this thesis we shall perform the comparisons of a Krylov Subspace Spectral method with Forward Euler, Backward Euler and Crank-Nicolson to solve the Cable Equation. The Cable Equation measures action potentials in axons in a mammalian brain treated as an ideal cable in the first part of the study. We shall subject this problem to the further assumption of a non-ideal cable. Assume a non-uniform cross section area along the longitudinal axis. At the present time, the effects of torsion, curvature and material capacitance are ignored. There is particular interest to generalize the application of the PDEs including and …

Genetic Population Structure And Effective Number Of Breeders In Systems Across The Range Of The Gulf Sturgeon, Jacob Zona

Master's Theses

Gulf sturgeon (Acipenser oxyicnhus desotoi) are a large, anadromous fish belonging to an ancient lineage that diverged as early as 400 MYA. Overfishing for meat and caviar during the early 1900’s reduced their range and abundance and continued habitat destruction and mortality have limited their ability to recover, leading to their listing under the Endangered Species Act. This study uses genetic techniques to determine the effective number of breeders for multiple spawning groups of Gulf sturgeon in river systems across their range to set a baseline for tracking reproductive success of the species. Accompanying genetic information relevant to …

Predictive Ability Of A 3d Body Scanning Mobile Application For Metabolic Health Risk, Caleb Brandner

Master's Theses

There is an increasing prevalence of obesity within the US and rising rates of metabolic syndrome among those aged 20-39 concurrent with a decrease in the reception of primary care. Limitations to healthcare including access, cost, and availability, highlighting the need for simple, efficient, and accessible cardiometabolic health risk screening. Given the surge in smartphone ownership over the last decade, this study sought to determine the predictive ability of a mobile 3D-optical (3DO) body composition assessment application in determining metabolic health risk. A total of 62 participants (female: 36) underwent traditional anthropometric measurements, 3DO body scanning using a smartphone application, …

Estimation Of Mortality Rates For The Gulf Menhaden Stock And Reference Point Implementation For The Fishery, Catherine Wilhelm

Master's Theses

The Gulf menhaden stock is the target of a large commercial fishery in the Gulf of Mexico. To address the needs of both the stock and fishery, I performed two studies. I first addressed the natural mortality rates currently used in the Gulf menhaden stock assessment. To update these rates, I used data from a tagging study conducted from 1970 to 1988. Adult and juvenile menhaden were tagged, released, and recovered in fish processing plants. To evaluate the data, I built a Bayesian model using the negative binomial distribution to estimate natural mortality, catchability, and the overdispersion factor parameters. I …

Connecting Social And Ecological Systems In Small-Scale Fisheries In The Philippines, Sara Eisler Marriott

Dissertations

Nearly 50% of all marine fish capture in the Philippines is from artisanal fisheries, most of which is un- or under-reported. As in many emerging nations around the world, the Philippines cannot fully address overfishing by managing only half of the catch that comes from commercial fisheries. Marine reserves are a popular governance strategy for conservation and of growing interest for fisheries management. Many marine reserves in the Philippines, however, are not considered effective. In 2014, Rare, an international NGO, implemented a community-based management program to increase the effectiveness of the marine reserves, and while it found biomass increased, there …

Effects Of Increased Shoe Collar Height And Limb Dominance On Landing Knee Biomechanics In Collegiate Volleyball Players, Lindsey Legg

Master's Theses

Athletic footwear with higher collar heights are worn to restrict ankle motion. Reduced ankle dorsiflexion has been associated with increased frontal plane knee motion. Volleyball players wear mid-cut shoes (MC) that have an increased collar height rising slightly superior to the talocrural joint and malleoli. The purpose of this study was to determine the effect of MC and limb dominance on knee landing mechanics. It was hypothesized that participants would land with greater initial contact (IC) and peak frontal joint plane angles and moments and smaller IC and peak sagittal plane joint angles and moments at the knee in MC …