Digital Commons Network^™

Mindfulness As A Protective Factor In Women’S Sexual Health, Shana Byerley

Electronic Theses and Dissertations

Many women who experience physical health complaints also report sexual dysfunction across a variety of domains including decreased arousal, desire and satisfaction. Although there are well-established connections between disease-specific populations and sexual dysfunction, less research has focused on women who experience somatic symptoms more broadly. Similarly, mindfulness as a treatment intervention has been applied across many facets of sexual functioning, but mindfulness as a trait characteristic has been less explored in its connections with generalized somatic complaints. Further, the within-domain interactions between facets of mindfulness and domains of sexual dysfunction have not been previously explored. Using data from an online …

Electrochemical And Electrocatalytic Properties Of Screen-Printable Carbon Inks Featuring Pyridinic Nitrogen-Containing Polymeric Binder, Albert Sam Junior

Electronic Theses and Dissertations

Screen-printable conductive inks have been widely applied to prepare electrodes for electrochemical sensing. These inks generally consist of conductive metal or carbon particles, solvents, and polymeric binders. Low-cost, carbon-based, screen-printable conductive inks are especially popular. However, screen-printed carbon electrodes (SPCEs) must often be modified after they are printed to impart the necessary characteristics (e.g., sensitivity, selectivity, stability) for the desired application. For example, nitrogen-doping of SPCEs, especially in ways that introduce pyridinic or pyrrolic nitrogen species, can impart electrocatalytic properties towards reduction of O₂, H₂O₂, and CO₂. While our previous work done …

Raptors As Secondary Dispersers Of Mycorrhizal Fungal Spores, Joseph Anderson

Electronic Theses and Dissertations

Animals aid fungal dispersal by consuming fruiting bodies (e.g., truffles) and depositing spores elsewhere. Predators can act as secondary dispersers by preying on small mammals that eat truffles, although it is unclear how this dispersal may vary among species of raptors (hawks and owls) and fungal taxa. We experimentally fed four truffle taxa (with spores varying in size and wall thickness) to six raptor species (with differing gut morphology and acidity) to assess how spore viability and retention time may change between raptor casts and feces. Viability in smaller spores was more negatively affected by acidity compared to larger spores …

Hierarchy In Sensation: Exploring The 40 Hz Auditory Steady State Synchrony In The Primary Auditory And Prefrontal Association Cortices, Deepshila Gautam

Electronic Theses and Dissertations

Auditory processing begins in the cochlea and ascends through brainstem relays to the cortex, where sound features with increasing complexity are encoded. The 40 Hz auditory steady-state response (ASSR) reflects induced gamma synchrony shaped by local cortical circuit dynamics. Disrupted 40 Hz ASSR is a consistent finding in schizophrenia, linked to N-methyl-D-aspartate receptor (NMDAR) hypofunction in inhibitory interneurons, making it a promising translational biomarker. While multiple ASSR generators have been identified, it is not known if these are redundant or represent unique activity. This dissertation investigates regional differences in 40 Hz ASSR across two principal generators: the primary auditory cortex …

An Evaluation Of Key Components Of Natural Resource Camps, Undergraduate Persistence And Success In Natural Resources, Brandy Bishop

Electronic Theses and Dissertations

This study explores the key components that connect natural resource camps, undergraduate persistence, and overall success through gainful employment within the natural resource industry. The aim of this study was to assess early interest and attitudes towards natural resource career pathways and how education interventions shape students’ career outcomes thus leading to overall success. A longitudinal mixed method design was used combining Conservation Careers Camp survey data (n = 39) with institutional records for Forestry majors (n =655) in the Arthur Temple College of Forestry and Agriculture on the Stephen F. Austin State University campus. Quantitative data was analyzed through …

Stand Strucuture Of Planted Stands In Storm-Water Retention Basins, Jason Lanza

Electronic Theses and Dissertations

Trees assist in stormwater retention basin functionality as efficient sources of water removal, and determining stand structure and leaf area of forests can be a measure of their effectiveness. The structure of forest stands on these basins managed for runoff mitigation has received little attention. We investigated the structure and species composition/diversity (tree and herbaceous) of planted, managed stands and naturally regenerated stands on stormwater retention basins managed by Harris County Flood Control District in Harris County, Texas. We determined stand structure variables (trees per hectare, basal area per hectare, quadratic mean diameter, relative density, average tree height, and percent …

A Tale Of Two Toxicants: Investigating The Interaction Between Hexavalent Chromium And Perfluorooctane Sulfonic Acid., Morgan Elizabeth Delnicki

Electronic Theses and Dissertations

Hexavalent chromium [Cr(VI)] and per- and polyfluoroalkyl substances (PFAS) are environmental contaminants of major public health concern. Despite commonly being found together in contaminated drinking water, no studies have considered the concomitant health effects of Cr(VI) and PFAS, specifically perfluorooctane sulfonic acid (PFOS). In vitro studies using CHO cells assessed the cytotoxicity and genotoxicity of Cr(VI) and PFAS both individually and in combination. Intracellular and extracellular Cr levels were measured with Atomic Absorption Spectrometry. PFOS was found to exacerbate Cr(VI) induced cytotoxicity and genotoxicity. Additionally, a novel in vivo model of studying the hepatotoxicity of Cr(VI) was established. Adult Hartley …

Exploring Hexavalent Chromium Exposure And Lipid Accumulation In Liver Disease., Gabrielle Celine Griffin

Electronic Theses and Dissertations

The prevalence of MASLD has doubled over the past 20 years and continues to rise. Hexavalent chromium [Cr(VI)], a top chemical hazard in U.S. drinking water, is emerging as potential risk factor for liver disease. To study the impact of Cr(VI) and high-fat diet on MASLD, we developed an in vivo model using Sprague-Dawley rats exposed to Cr(VI) in drinking water (0, 0.05, or 0.1 mg/L) and fed normal or high-fat diet for 90 days. High-fat diet significantly increased body mass, plasma lipoproteins, cholesterol, liver injury, and hepatic triglycerides, which were exacerbated by Cr(VI) exposure. Cr(VI) alone increased hepatic chromium …

An Exploration Of Lgbtq+ Runner Motivation And Constraints., Michael Clemons

Electronic Theses and Dissertations

Running offers extensive benefits beyond physical fitness, encompassing mental, emotional, and social advantages. However, LGBTQ+ individuals face unique challenges in participating in the running community, which remains predominantly White, cisgender, and heterosexual. With the LGBTQ+ population in the U.S. growing, there is a need to understand their motivations and barriers to participation in running events and training groups. This study explores these motivations using self-determination theory, comparing LGBTQ+ and non-LGBTQ+ runners to identify differences in driving factors such as social connectivity, self-esteem, and competition. Additionally, it examines barriers LGBTQ+ runners face, ranging from structural obstacles to intrapersonal challenges, and how …

Analysis Of An Ethanol Sensitive Bmp-Nkx2.3-Fgf Signaling Pathway In Pouch Morphogenesis., Hieu Dai Le Vo

Electronic Theses and Dissertations

Craniofacial malformations lie at the heart of Fetal Alcohol Spectrum Disorders (FASD). While there is growing evidence for a genetic component to FASD, little is known of the cellular mechanisms underlying these ethanol-sensitive loci in facial development. Bone Morphogenetic Protein (Bmp) signaling pathway dependent pouch formation is a key mechanism in facial development. We have previously shown that multiple Bmp mutants are sensitized to ethanol-induced facial defects. However, ethanol does not directly impact Bmp signaling. This suggests that downstream effectors, like nkx2.3 and Fibroblast Growth Factor (Fgf) signaling, may mediate the impact of ethanol on Bmp mutants. Here, I …

Coastal Transition Zone Development Effects On Salt Marsh Ecology, Amanda Mei Pysher

Electronic Theses and Dissertations

The coastal transition zone (CTZ) is a regional gradient linking terrestrial and marine systems, comprising of the terrestrial upland, the marsh-upland ecotone, and estuarine salt marshes. Along all US coastlines, including the South Carolina (SC) coast from Little River to Georgetown, increases in anthropogenic development of terrestrial uplands have altered the historically established vegetation, and various physical, chemical, biological, and geological gradients. Despite the CTZ's ecological importance, the trickle-down effects of terrestrial upland development on associated high marsh habitats remain understudied. Data were collected from developed (DEV) and undeveloped (UND) shorelines across three SC estuarine inlets. Multilevel modeling (MLM) was …

Migratory Patterns Of Juvenile Shortfin Makos (Isurus Oxyrinchus): Evidence Of A Nursery In The Western North Atlantic, Julia A. Crews

Electronic Theses and Dissertations

Shortfin Makos, Isurus oxyrinchus Rafinesque, 1810, are lamnids that have a global distribution in temperate and tropical oceans. Locations of critical early life history events including birthing and nursery areas are unknown or unconfirmed for most populations. The objective of this study was to identify if a nursery area for Shortfin Makos in the northern waters of the Mid-Atlantic Bight using the criteria articulated by Heupel et al. (2007). Satellite tags were used to track the movement of juveniles (<200 cm TL, n=7) up to 5 months. Tag detections (n=882) confirmed that young makos stay in continental shelf waters of the northern Mid-Atlantic Bight off Long Island through the meteorological summer (June–August) and early meteorological fall (September–October) when sea surface temperatures are 18–23°C. There was clear migratory movement from juveniles once sea surface temperatures fell below 15°C. During late fall, some young sharks moved south towards Cape Hatteras, North Carolina, while one shark moved east up to 1,800 km into the open north Atlantic Ocean into meteorological winter. These movement data of juvenile Shortfin Makos combined with multi-year catches and sightings (2018–2024) provide strong evidence for a nursery area in the northern Mid-Atlantic Bight. By identifying a nursery area for Shortfin Makos, knowledge gaps that currently exist for this vulnerable species and support effective management can be closed.

Comparison Of Nutrient Concentrations And Primary Production Indicators Across Plume Fronts, Taylor Dishon

Electronic Theses and Dissertations

Coastal buoyant plumes carry low-salinity waters containing particulate and dissolved terrestrial materials with an abundance of nutrients into the coastal ocean, including inorganic nitrogen and phosphorous. Plume fronts act as transport barriers created from the convergence of a fresher plume with an older, saltier plume or with ambient waters, leading to potential accumulation of phytoplankton and nutrients. This accumulation creates an optimal environment for primary production. The primary goals of this study were: to investigate the distribution of and potential relationships between nutrient concentrations and chlorophyll a across plume fronts of the Winyah Bay River Plume, and examine potential relationships …

Site Fidelity, Seasonality, Movement, And Fish Associates Of Sand Tigers Carcharias Taurus In North Carolina, Ara L. Mcclanahan

Electronic Theses and Dissertations

Sand tigers Carcharias taurus are mackerel sharks with a disjunct global distribution in tropical and temperate seas. In the northwest Atlantic, sand tigers migrate along the coast of the eastern United States from the Gulf of Maine to Florida and occupy structurally complex benthic habitats. The long-term, underwater camera installation, SharkCam, at Frying Pan Tower, off Cape Fear, North Carolina, USA, sits atop an expanse of hard bottom reef frequented by sand tigers. The citizen-science platform Spot A Shark USA (SAS USA) uses images of sand tigers to identify and track individuals. This study utilized image encounters from SAS USA …

Investigating The Multiple Enzyme Complex In The Carotenoid Biosynthesis Pathway, Mercy Mormor

Electronic Theses and Dissertations

In nature, plant carotenoids are 40-carbon isoprenoids with polyene chains that may have double bonds. They are vital components of all photosynthetic organisms, playing several roles in the plant cell, including photosynthesis, pigmentation, phytohormone synthesis, signaling and photoprotection. In this study, we investigated protein-protein interactions among key enzymes involved in the carotenoid biosynthesis pathway using the Bimolecular Fluorescent Complementation (BiFC) assay. Our results revealed several interactions that suggest a coordinated regulation of enzymatic activity within this pathway, highlighting potential regulatory complexes that influence carotenoid production. The study also highlights the pivotal role of Zeta-Carotene Isomerase (Z-ISO) as a key regulatory …

Gut Passage Time In Small Mammals: Influences Of Small Mammal Traits, Digesta Phase, And Particle Morphology, Noah G. Hale

Electronic Theses and Dissertations

Dispersal is crucial in maintaining healthy ecosystems, but little is known about mechanisms influencing fungal spore dispersal by animals. We aimed to develop a more mechanistic understanding of the influence of fungal spore traits and small mammal traits on gut retention time. We fed three species of small mammals (shrew, mouse, vole), which differ in gut morphologies, digestive strategies, and activity a combination of markers including: liquid digesta phase (CrEDTA), small particle (fungal spores with diverse morphologies), and large particles (glitter and beads, representing plant cells and seeds, respectively). We found that hindgut fermenters selectively retained the liquid markers, spores …

Cattle Regenerative Grazing Effects On Bat Activity In Southern Appalachia, Seth Morelock

Electronic Theses and Dissertations

Livestock farming accounts for about 70% of agricultural activity, with continuous grazing as the dominant conventional practice. However, this method often degrades biodiversity and ecosystem health through overgrazing. Regenerative grazing practices offer a potential ecologically sustainable approach to cattle management. Insectivorous bats are known to use agroecosystems for foraging and roosting habitats, offering an opportunity to assess their response to regenerative grazing. Using passive acoustic monitors, we evaluated the response of bats to cattle within regenerative grazed farms in East Tennessee, USA. Overall bat activity declined when cattle entered and exited paddocks, except for the tri-colored bat (Perimyotis subflavus …

"No One Leaves For Free": A Media Analysis Of The Lived Experiences And Cumulative Impacts Of The Flint Water Crisis., Jordan Leigh Gatewood

Electronic Theses and Dissertations

In April 2014, the city of Flint, Michigan changed their municipal water source from Lake Huron to the Flint River. The effects of this change have been felt far and wide as news broke across the nation that this water was contaminated with lead and residents of Flint were getting sick. This research analyzes 170 news articles from three local and three national news outlets over a 10-year span, 2014 to 2024, to determine how community voice is presented in news media to portray the lived experiences and cumulative impacts of the Flint Water Crisis. Applying a Critical Environmental Justice …

Mixture Effects On Metal Accumulation In The Asian Clam, Corbicula Fluminea, Mark A. Huff

Electronic Theses and Dissertations

Field collected Corbicula fluminea were exposed to trace level copper, lead, and zinc with the aim of examining the preferential accumulation between the soft tissue and shell. Metal levels were based on those in a permitted industrial effluent. At 1X effluent and 2X effluent exposure levels, copper was found to preferentially accumulate in the clam soft tissue, lead was found to preferentially accumulate in the clam shell, and zinc was found to excrete back into the diluent after preferentially accumulating in the clam soft tissue. When exposed as a mixture at 1X effluent levels, copper and lead were found to …

Isolation And Characterization Of Siderophore(S) From Pseudomonas Mosselii, Casey J. Stophel

Electronic Theses and Dissertations

Iron is essential for growth of most microorganisms. It functions as an important cofactor in many important biological processes. However, iron found in soil is rendered insoluble and unavailable to microorganisms for use. To overcome this, many bacterial species produce siderophores, a small organic molecule that has high affinity for iron. Siderophores allow for bacterial cells to obtain otherwise insoluble iron. Pseudomonas mosselii, a Gram negative bacterium, was isolated from a local soil sample. P. mosselii was found to produce siderophore(s) under iron restricted environment, however, they have not been characterized. Therefore, it was of interest to isolate, purify and …

Investigating The Impact Of Psychoactive Plant Alkaloids On Bumblebee Behavior, Skylar Mathieson

Electronic Theses and Dissertations

The relationship between plants and their pollinators is often framed as a food-for-service exchange in which plants provide pollinators with nutrients in exchange for transport of their gametes. However, in addition to essential nutrients, many floral rewards (nectar, pollen) also contain defensive toxins such as alkaloids, with largely unexplored consequences for plant-pollinator interactions. I investigated how three psychoactive and addictive plant alkaloids — caffeine, nicotine, and morphine — affect foraging behavior in generalist bumblebees (Bombus impatiens) using robotic flowers. Each of these chemicals affected pollinator foraging behavior, influencing the number and duration of their visits to flowers in …

Drivers And Consequences Of Changes In Nectar Microbiome Composition Across Spatial And Biological Scales, Daniel A. Barker

Electronic Theses and Dissertations

Microbial communities inhabiting floral nectar, known as the nectar microbiome, are important mediators of plant-pollinator interactions. However, the ecological and environmental factors that shape the composition of these microbial communities remain poorly understood. While previous studies have examined the effects of a few microbial groups, typically independent of one another, on one plant or pollinator species, this dissertation takes a wide-scale approach to explore how abiotic conditions and biotic interaction’s structure microbial communities within floral nectar. Furthermore, I also quantify how variation in microbial richness and identity influences pollinator behavior and plant reproductive success.

This dissertation shows that microbial abundance …

Changing Globally, Acting Locally: Responses Of Coastal Plant Functional Traits To Global Change Are Mediated By Biotic And Abiotic Interactions., Shannon L. Walker

Electronic Theses and Dissertations

We live in a time of rapid global change with substantial consequences for planet-wide functioning. Local ecosystems reflect this change, yet we struggle to predict their responses. Coastal ecosystems, like dune and interdunal wetlands, have declined rapidly and predicting their responses to global change is essential for future management. Functional traits may be particularly informative as they drive species and ecosystem responses and can provide generalizable findings. This dissertation investigates how global change, especially anthropogenic nitrogen (N) enrichment, interacts with abiotic and biotic factors to affect coastal sand dune and interdunal wetland plant functional traits. First, I used a long-term …

Peer Functioning And Risk For Co-Occurring Adhd And Anxiety Symptoms In School-Aged Children: A Cross-Sectional And Longitudinal Analysis., Helena F. Alacha

Electronic Theses and Dissertations

Background. Youth with Attention-deficit/hyperactivity disorder (ADHD) often have higher rates of anxiety in comparison to their peers without ADHD. Children with co-occurring ADHD and anxiety exhibit a unique clinical presentation that poses challenges to both assessment and treatment. Consequently, children with comorbid ADHD and anxiety experience increased impairment, and often have poorer long-term outcomes than children with either ADHD or anxiety alone. Preliminary evidence suggests that different psychosocial phenomena commonly experienced by children with ADHD—such as peer functioning—may increase susceptibility to anxiety. Considering that children with ADHD encounter a range of peer difficulties, the present study proposed and evaluated different …

Effects Of Perfluorooctane Sulfonate In A Mouse Model Of Alcohol-Associated Liver Disease., Paxton Michelle Brizendine/Ames

Electronic Theses and Dissertations

Perfluorooctane sulfonate (PFOS), a pervasive environmental pollutant, has been increasingly associated with the development of metabolic dysfunction-associated steatotic liver disease (MASLD); nonetheless, its connections with alcohol-associated liver disease (ALD) have not been well studied. This study investigates the hypothesis that PFOS exposure alters hepatic metabolism, thereby leading to alterations in ALD severity. Male C57BL/6J mice were fed isocaloric control or 5% ethanol (EtOH) diet for 15 days. From day 6 of feeding, mice were concurrently gavaged with 1 mg/kg PFOS or 2% Tween-80 vehicle for 10 days, followed by a 5 g/kg EtOH binge dose. PFOS and ethanol co-exposure significantly …

Cbl Regulation Of C-Met Signaling In Corneal Epithelial Cells., Kate Elise Tarvestad Laise

Electronic Theses and Dissertations

The cornea is the most anterior portion of the eye and permits light passage through to retina, allowing formation of a clear image as long as it remains healthy. If the cornea sustains damage, it creates and entrance for foreign body invasion, infection, and ultimately blindness in the immunocompromised eye. Healing the corneal tissue is critical for vision restoration and pain alleviation, as it is the most densely innervated tissue in the body. Growth factors and their cognate receptors are currently under investigation as tools to restore proper corneal physiology. We hypothesize that manipulating the hepatocyte growth factor (HGF) /c-Met …

Metabolic Regulation Of Cardiac Fibroblast Phenotype And Function., Collin Kleis Wells

Electronic Theses and Dissertations

Cardiac fibroblasts are central effectors of cardiac repair after myocardial infarction (MI). In response to signaling cues, they differentiate to a range of phenotypes with robust capacities to synthesize and secrete extracellular matrix (ECM) and signaling molecules. Although activated fibroblast phenotypes are associated with pronounced changes in metabolism, it remains unclear how the metabolic network upholds the effector functions of fibroblasts in the post-infarcted heart. Here, we identified that critical enzymes in the phosphoenolpyruvate (PEP) cycle, i.e. pyruvate kinase muscle-2 (PKM2) and phosphoenolpyruvate carboxykinase-2 (PCK2), are elevated in the heart after MI and examined their role in regulating post-MI remodeling …

Estimation Methods For Bayesian Exponential Random Graph Models Under The Horseshoe Prior., Pamela Linares

Electronic Theses and Dissertations

Networks are powerful tools for modeling the complexity of social interactions, biological systems, and information spread. A leading statistical frameworks for analyzing network data are Exponential Random Graph Models (ERGMs), which provide a principled approach to capturing structural dependencies. However, ERGMs remain challenging to estimate, especially in sparse or high-dimensional settings where models suffer from degeneracy and unstable parameter inference. This paper proposes a penalized Bayesian approach to ERGMs that utilizes the horseshoe prior, a sparsity-inducing global-local shrinkage prior. This prior offers robust regularization while preserving important signals, improving estimation by shrinking irrelevant parameters and reducing the impact of extreme …

Recent Studies On The Reactions And Synthesis Of Nitrogen And Sulfur - Containing Heterocyclic Pharmacophores., Bernard Louis Adjei

Electronic Theses and Dissertations

Nitrogen and sulfur-containing heterocycles remain significant classes of compounds in the field of medicinal and organic chemistry due to their unique structural features and diverse biological activities which make them of considerable interest for drug discovery and development. Notable examples of the nitrogen containing heterocycles include the phthalimide and glutarimide rings present in thalidomide. Thalidomide, a potent small-molecule therapeutic agent, precipitated a significant global drug crisis due to its teratogenicity, causing congenital malformations in phocomelia infants, which remains unrivaled over half a century ago. Currently, thalidomide derivatives are extensively utilized in the therapeutic management of various hematological malignancies. Recent investigations …

Ecosystem Services Of Urban Green Spaces In Louisville, Ky., Julia Kachanova

Electronic Theses and Dissertations

Accelerating urbanization poses critical challenges to urban green spaces (UGS), vital for ecological balance and human health. Rapid development often results in fragmented habitats, biodiversity loss, and diminished ecosystem service delivery. There is an urgent need to explore and evaluate novel strategies capable of enhancing urban resilience, such as implementing urban orchards, and managing existing parks and gardens in sustainable ways. This dissertation explores how different forms of urban green spaces (UGS) contribute to the provision and maintenance of critical ecosystem services that support human well-being and urban biodiversity. By analyzing UGS impact on ecosystem service provisioning and long-term sustainability, …