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Comparative Functional And Computational Analyses Of Primate Seminal Proteins: Insights Into Sexual Selection And Hiv/Siv, Emine Feride Kahveci

Electronic Theses and Dissertations

Male reproductive protein-coding genes are among the most rapidly evolving genes across many animal taxa, commonly attributed to sexual selection; however, pathogen defense mechanisms might also be contributing factors. This study aimed to both computationally and experimentally investigate the selective pressures responsible for the rapid evolution of seminal proteins. In the first part, the research focused on sexual selection in the form of post-copulatory sperm competition as a driving force behind the evolution of kallikrein related peptidase 3 (KLK3), also known as prostate-specific antigen (PSA), a key prostatic seminal protein. KLK3 is responsible for the liquefaction of semen coagulum through …

Patterns And Potential Mechanisms Of Phenotypic Changes In Urban Small Mammals, Leslie Lopez

Master's Theses

Urbanization is an example of human induced rapid environmental change that can have wide-reaching ecological effects, including habitat destruction, fragmentation, and alteration of local climates. Effects of urbanization have been shown to impact wildlife, as disturbances resulting from urbanization can create novel environments and selective pressures that could lead to changes in morphology, physiology, or both. Small mammals such as rodents are an ecologically important set of wildlife species because they are a key prey item for several predators, hold strong influence over plants as a primary consumer, and some species carry and transmit major human and animal diseases. Previous …

Inducible Crispr-Targeted ‘Knockdown’ Of Human Gut Bacteroides In Mice Reveals Glycan Utilization Strategies, Zachary Beller

Arts & Sciences Graduate Student Theses and Dissertations

Learning how members of the human gut microbiota compete and cooperate for dietary nutrients, such as fiber-associated glycans, should help facilitate development of more precise nutritional recommendations for improving health. To model how bacteria prioritize the utilization of different fiber glycans in the mammalian gut, germ-free mice were colonized with a 13-member consortium of cultured, genome-sequenced human bacterial strains, including seven Bacteroides species. Animals were fed a Western diet supplemented with pea fiber. Once the consortium had time to assemble, an inducible CRISPR-based system was used to deplete the absolute abundance of Bacteroides thetaiotaomicron or B. cellulosilyticus by 10- to …

Greening The Edge: Investigating Riparian Buffer Restorations In A Pastoral Setting And Their Effects On Soil Carbon And Microbial Community Composition., Seth Mccullough

Masters Theses, 2020-current

Riparian buffer restoration represents a critical strategy for enhancing ecosystem health and resilience in agricultural landscapes. This study investigates the effects of riparian buffer restoration on soil properties, microbial communities, and carbon dynamics in Rockingham County, VA. Through a comprehensive field study, we assessed the physicochemical properties of soil, microbial biomass, community composition, and soil carbon storage in restored and unrestored riparian buffers. Our findings reveal significant improvements in soil physical properties in restored buffers, including increased soil moisture (p < 0.05) and decreased bulk density (p < 0.01), indicating enhanced soil structure and water retention capacity. While no significant differences were detected in soil pH or cation exchange capacity, restored buffers exhibited higher soil carbon stocks (p < 0.05) and carbon-to-nitrogen ratios, suggesting potential differences in nutrient cycling processes and organic matter decomposition rates. Moreover, restored buffers showed increased microbial biomass (p < 0.01), potentially driven by improved habitat conditions and shifts towards a fungal-dominated microbial community.

Although no significant differences were found in overall microbial community composition between restored and unrestored sites, specific shifts in bacterial …

Histone Changes As A Response To Lactic Acid Selection In Cells Of Austrofundulus Limnaeus, Lori Tran, Jason Podrabsky, Chelsea Hughes

Student Research Symposium

The killifish Austrofundulus limnaeus is an extremophile native to small temporary ponds of Venezuela. Normal embryonic development of A. limnaeus is segmented into up to three stages of metabolic depression (diapause), and both developing and diapausing embryos can survive long bouts of the complete absence of oxygen (anoxia) by using anaerobic metabolic pathways. While there has been much focus on how mutations in DNA drive evolution, environmental stress can cause heritable changes to histone post-translational modifications (hPTMs) in multiple species. However, this evolutionary role of hPTMs has never been studied in A. limnaeus. Additionally, the possible evolutionary role of extracellular …

Antimicrobial Mechanisms Of Human Lipocalin-2, Lindsey Steinberg

Arts & Sciences Graduate Student Theses and Dissertations

Lipocalin-2 (Lcn2, also known as siderocalin or neutrophil gelatinase-associated lipocalin) is an innate immune protein released by neutrophils and epithelial cells at sites of infection. It is understood to limit bacterial growth by restricting access to iron, an essential nutrient, but it does not avidly bind iron in isolation. At least two iron restricting Lcn2 mechanisms are described in the literature. In the prototypical mechanism, Lcn2 binds and prevents uptake of enterobactin, a high affinity iron chelator secreted by E. coli and closely related Enterobacterales. Sequestration of this bacterial siderophore prevents nutritional iron delivery to these pathogens. However, the narrow …

Identification Of Potent Pan-Ephrin Receptor Kinase Inhibitors Using Dna-Encoded Chemistry Technology, Chandrashekhar Madasu, Zian Liao, Sydney E Parks, Kiran L Sharma, Kurt M Bohren, Qiuji Ye, Feng Li, Murugesan Palaniappan, Zhi Tan, Fei Yuan, Chad J Creighton, Suni Tang, Ramya P Masand, Xiaoming Guan, Damian W Young, Diana Monsivais, Martin M Matzuk

Faculty, Staff and Students Publications

EPH receptors (EPHs) are highly sought-after drug targets owing to their essential roles in maintaining appropriate cellular functions in both physiological and disease conditions. However, limited potency and specificity pose significant obstacles to the development of small-molecule inhibitors for EPHs. Here, using high-throughput DNA-encoded chemical library screenings, we developed potent and selective inhibitors of the EPH receptor kinase family. Our results also emphasize the therapeutic potential of our EPH inhibitors in cancer and endometriosis, a global health concern that causes chronic pain and often leads to infertility in women. This study showcases the robust pipeline of using DNA-encoded chemistry technology …

Measuring The Effects Of Selenium Exposure On Batrachochytrium Dendrobatidis (Bd) Growth In Vivo In Larval American Bullfrogs (Rana Catesbeiana)., Taylor Morrison

Honors Thesis

Most amphibians in today’s world are exposed to a variety of environmental stressors. This project’s main objective was to determine any effects of selenium on Batrachochytrium dendrobatidis (Bd) and infection levels in South Dakota amphibians. I selected American bullfrogs (Rana catesbeiana) as they are susceptible to Bd and are found throughout eastern South Dakota. The secondary objective of this project was to measure any impact of Bd and selenium, combined, on growth measures of the frogs. The third objective was to see if survival rates were reduced when amphibians were exposed to Bd and selenium. Tadpoles were collected (n=225) from …

Beating The Heat: The Use Of Coral-Benefitting Bacteria For Heat-Stressed Anemones And Inspiring Future Biologists, Navah Eshraghi

Undergraduate Honors Theses

The warming of ocean temperatures has caused mass coral-bleaching events characterized by the expulsion of vital algal symbionts from coral tissues. However, the possibility of algal reuptake and existence of bacteria that support coral-algal symbiosis are two avenues of potential restoration efforts. Using the sea anemone Exaiptasia diaphana as a model for corals, I tested whether the coral-benefitting bacterium Endozoicomonas montiporae could enhance algal uptake under ambient (27°C) and heat-stressed (32°C) conditions. I then turned acquired results into an article modeled after National Geographic Kids to introduce the experiment to younger ages. While temperature was a larger determinant of algal-uptake …

Assessing The Effects Of Cold Storage Regimes Of North American Bombus Gynes, Thuy Tien T. Lindsay, Marcia M. Hagen, Joyce N. Knoblett, Joseph P. Rinehart, Karen M. Kapheim, James P. Strange

Biology Faculty Publications

Bumble bees are the primary commercial pollinators for greenhouse-grown crops and managing them requires insight into the Bombus life cycle. However, some aspects of the life cycle are not fully understood. Once mated, adult Bombus gynes can be stored for a short term at a constant low temperature (CLT). However, survival rates for some species are low during CLT, particularly when storage periods exceed a month. To address this, we tested the hypothesis that Bombus gynes stored in a fluctuating thermal regime (FTR) have increased survival compared to gynes stored in CLT. Specifically, the FTR had a baseline temperature of …

The Effect Of Integrated Pest Management On Nutrition Of Bee Collected Pollen, Kaitlyn Bresnahan '25

Biology Student Scholarship

Honey bees are the world’s most commercially valuable pollinators, and they face many threats. The greatest challenge facing honey bees is Varroa mites, parasitic mites that feed on bees’ fat bodies, killing bees and spreading diseases. While chemical treatments are available to stop the spread of mites, these treatments are insecticides, which are not ideal to put in a hive of insects. A popular organic method of mite management is using drone comb. Drone brood is preferentially chosen by mites for ovipositing and development because of its larger size and longer development time, so removing drone brood can drastically reduce …

Mental Health And Traumatic Occupational Exposure In Wildland Fire Dispatchers, Robin M. Verble, Rachel Granberg, Seth Pearson, Charlene Rogers, Roman Watson

Biological Sciences Faculty Research & Creative Works

Wildland Fire Dispatchers Play a Key Role in Wildland Fire Management and Response Organization; However, to Date, Wildland Fire Studies Have Largely Focused on the Physical Hazards And, to a Lesser Extent, Mental Health Hazards of Wildland Firefighting Operational Personnel, and Dispatcher Studies Have Primarily Focused on 911 and Police Dispatchers. Studies of Other Dispatchers Have Provided Some Limited Insight into Potential Strains Impacting This Workforce, Including Work-Related Fatigue, Burnout, and Traumatic Exposure. However, the Specific Job Hazards that Are Faced by Wildland Fire Dispatchers Are Poorly Understood. in 2023, We Conducted a Cross-Sectional Survey of 510 Wildland Fire Dispatchers …

Use Of Space By Urban Loggerhead Shrikes (Lanius Ludovicianus) As A Window Into Habitat Suitability, Katie A. Maddox, Christopher E. Hill

Biology

Wild animals in urban environments face new challenges that may change how they use space and, at the same time, how they use space provides clues to suitability of habitat: bird territories in desirable areas tend to be smaller and populations denser. Loggerhead Shrikes (Lanius ludovicianus), historically associated with shortgrass habitats such as pasture and shrub steppe, occur widely in urban areas of the southeastern United States. For a complete picture of shrike use of space in urban spaces, we present three measures for a population inhabiting urban areas of Horry County, South Carolina: population density, home range size, and …

The Combined Effects Of Nacl And Beet Juice On Germination And Early Seedling Growth Among Raphanus Sativus L., Justin Howell

Theses, Dissertations and Culminating Projects

Salt pollution and soil salinization via secondary pathways is a global problem. One practice which contributes to increased salinity in soils and other natural systems is the application of road deicers in colder regions. Increased salinity in soils negatively affects plant growth and microbial activity. In an effort to decrease the amount of salt applied to roads, salts are applied as brine. Liquid organic additives are incorporated into these brines to foster better adherence of the salt to impermeable surfaces. One common additive is beet juice, a byproduct of sugar extraction. Beet juice contains high levels of phosphorus and organic …

Searching For Regulators Of Catalase Activity Using Enzymatic Screens, Aram Joseph Alaxanian

Legacy Theses & Dissertations (2009 - 2024)

Catalase is found in a plethora of organisms and plays a crucial role in safeguarding cells against oxidative stress-induced damage to proteins, RNA, and DNA. Catalase catalyzed the decomposition of hydrogen peroxide (H2O2) into oxygen and water. Deficiencies in catalase have been linked to pathological conditions such as Diabetes, Alzheimer's, and Cancer, underscoring its significance in cellular health. In bacteria like Escherichia coli, catalase is encoded by two genes, KatG and KatE, both subject to regulation through transcription, translation, and post-translational modification. Our study focused on assessing the catalase activity of mutants lacking stress response genes (e.g., lexA, soxR, soxS, …

Interplay Between Cellular Stress Mechanisms And Immune Responses In Restricting Zika Virus Infection, Pheonah Badu

Legacy Theses & Dissertations (2009 - 2024)

Flavivirus infections pose significant global health risks, often leading to serious neurological and congenital complications such as microcephaly. These viruses induce complex cellular stress responses pathways encompassing the Unfolded Protein Response (UPR), Integrated Stress Response (ISR), autophagy, apoptosis, and the antiviral immune response, which dictate cell fate by either promoting survival to combat virus-induced damage or initiating cell death under prolonged stress. Despite the antagonizing functions, flaviviruses employ various subversion strategies, facilitated by viral proteins, to ensure successful infections even in the presence of activated cellular responses. Recent studies highlight dynamic interactions among stress response pathways during infection, emphasizing the …

Bilateral Asymmetry In The First Metacarpal: The Influence Of Handedness In Humans And Non-Human Primates, Lucyna A. Bowland

Graduate Theses and Dissertations

Muscle attachment sites (entheses) are often used to infer soft tissue anatomy and reconstruct behaviors within skeletal populations, but there remains a significant debate about whether and to what degree muscle use is accurately reflected in bony morphology. One of the most difficult problems in establishing the relationship between variation in muscle use and entheseal development is the inability to exclude a variety of external factors thought to influence enthesis development, including age, sex, body mass, and activity patterns. One way around this is to take advantage of the fact that humans are handed (preferentially using one hand over another, …

Inhibition Of Foxo Induces Oxidative Stress In Osteosarcoma, Kai K. Brown

Theses (2016-Present)

Redox homeostasis is a balance between reactive oxygen species (ROS) generation and neutralization by antioxidants. Oxidative stress (OS) results when the generation of ROS exceeds the neutralizing capacity of endogenous antioxidants. Reactive oxygen species are generated during cellular processes such as mitochondrial activity or metabolism of drugs. Expression of endogenous antioxidants is driven by redox-sensitive transcription factors; therefore, redox-sensitive transcription factors are essential for the maintenance of cellular redox homeostasis. There are several redox-sensitive transcription factors that contribute to the expression of endogenous antioxidants. These redox-sensitive transcription factors include nuclear factor erythroid 2-related factors (Nrf-2), hypoxia-inducible factor (HIF), activator protein-1 …

Biosorption Of Lithium Using Microbes, Adebola Daisy Olade

Theses (2016-Present)

Lithium (Li) is a very valuable metal that is used across several industries including ceramics, glass, batteries, pharmaceuticals, and polymers. However, in recent years, the global demand for Li and its market price have increased considerably, due to its application as a critical component in the production of rechargeable Li-ion batteries and energy storage systems that are used in electric vehicles and a variety of electronic devices. Although Li occurs as a mineral in hard rocks and salt brines, substantial amounts are found in our environment as part of industrial wastes and oil-field wastewaters. Despite its importance, Li is also …

The Optimal Timing Of Abscisic Acid Treatment In Arabidopsis Under Drought And Salt Stress, Khelia Gihozo

Graduate Student Dissertations, Theses, Capstones, and Portfolios

As climate change intensifies, harsh environmental conditions, such as increased drought and salt levels, will pose significant challenges to agricultural productivity globally. It is important to develop strategies for plants to tolerate these adverse conditions. This study aims to investigate how well the timing of abscisic acid (ABA) treatment can promote resistance to salt and drought in Arabidopsis thaliana grown on Murashige and Skoog agar medium. The study evaluates both wild-type and transgenic lines overexpressing the DREB2A gene, a transcriptional activator involved in the stress response of plants. Plants were exposed to drought and salt stress as they matured. Followed …

Survey Of The Bolctes From Fish River Nature Preserve, Noah T. Nelson

Honors Theses

Boletes are a special kind of mushroom inside of the Kingdom Fungi that are distinguished from other mushrooms by their uniquely pored hymenium, as opposed to gills. Many boletes are ectomycorrhizal, meaning they are mutualists with vascular plants, and thus beneficial to the overall health of the terrestrial ecosystem. Some are well-known for their edibility and are of economic importance. In the United States 59 genus-level clades comprising 290 operational taxonomic units have been reported. The southeastern US and Gulf Coast regions however are less researched and recorded for their mushroom ecology. In Alabama, only 56 bolete species have been …

Mixed Methods Approach To Assess ‘Placental Opioid-Enhancing Factor’ Activity Within ‘Alternative’ Health Contexts Of Human Maternal Placentophagy, Jacob C. White

UNLV Theses, Dissertations, Professional Papers, and Capstones

Rats with elevated opioid levels experience an even greater increase in pain threshold after placenta or amniotic fluid consumption via placental opioid-enhancing factor (POEF) in the afterbirth. POEF only enhances opioid hypoalgesia; it cannot produce hypoalgesia alone. Although the POEF molecule remains unidentified and its efficacy in humans is unknown, it could be a safe, novel pain treatment. People who consume placenta as an alternative postpartum health practice are ideal for testing POEF bioactivity. Though rat models show that bioactive POEF is highly sensitive, some forms of the practice in humans may conserve POEF.

This project is the first attempt …

Dispersal Movement And Overwintering Ecology Of A Cryptic Migratory Forest Owl, Mitchell Lee Pruitt

Graduate Theses and Dissertations

Understanding species’ distributions and how a species uses its environment is a vital aspect of ecology and important for the development and implementation of conservation planning. In migratory species, with distinct breeding and nonbreeding ranges, understanding distributions is a complex endeavor. Nevertheless, evaluating movement behavior by linking seasonal distributions and identifying source areas is vital for understanding a species’ full annual cycle ecology. Understanding distributions is particularly important for predators, like birds of prey, that can exert top-down effects on community structure and ecosystem function through their influence on prey populations. Among raptors, owls are severely understudied in large part …

Role Of Arabidopsis Ltp12 In Environmental Stress Response, Bikram Giri

Electronic Theses and Dissertations

Lipid transfer proteins (LTPs) constitute a pervasive class of small proteins implicated in many biological and physiological processes, including seed development, germination, cuticle formation, and abiotic stress responses. In this study, we explored the role of Arabidopsis LTP12 protein in mitigating environmental stresses. To address this, we analyzed the T-DNA knockout mutant ltp12, focusing on its responses to salinity and osmotic stress. Utilizing antioxidant enzyme assays, phenotypic analyses (including water loss, chlorophyll content, seed germination rates, root length, and relative water content), and lipid profile analysis via Thin Layer Chromatography (TLC), we found that ltp12 mutants showed reduced catalase and …

Characterization Of The Role Of Tobacco Deacetylase Enzyme Sip-428 In Mediating Environmental Stress, Zahra Barati

Electronic Theses and Dissertations

Abiotic stress poses a significant threat to crop productivity and food security. In this study, we focused on understanding the role of SIP-428, a SABP2-interacting protein, in mediating plant responses to environmental stresses. Transgenic tobacco plants overexpressing SIP-428 were subjected to salinity and drought stress. The overexpression of SIP-428 led to diminished growth under both stress conditions, indicating a negative impact on stress tolerance. Specifically, SIP-428 overexpression resulted in a reduction in catalase activity, while peroxidase activity remained unaffected. These findings suggest that SIP-428 plays a negative regulatory role on the catalase activity during abiotic stress, which may contribute to …

Syntaxin-3 Mediates Baseline And Stimulated Mucin Secretion, Brianne Wharton

Dissertations and Theses (Open Access)

There are two rates at which airway epithelial cells secrete mucin. The low baseline rate accounts for ciliary clearance, and the high stimulated rate obstructs airways in protection from helminths or in obstructive pulmonary diseases. The exocytosis of mucins occurs via the four-helix SNARE complex. The SNARE proteins contributing helices are the vesicle-SNARE VAMP, and the target-SNAREs SNAP and Syntaxin. Coiling of the complex fuses the granule and plasma membranes to release mucins into the extracellular space. The VAMP and SNAP isoforms mediating baseline and stimulated secretion are known, but the Syntaxin (Stx) isoform remains unknown.

Three candidate exocytic Stx, …

Exploring Novel Nutrient Acquisition Mechanisms For Maintaining Energy Metabolism In Toxoplasma Gondii, Melanie Key

All Dissertations

Toxoplasma gondii is an infectious intracellular parasite that establishes infection within various mammalian hosts, including humans. Toxoplasma infects approximately one-third of the global population, making it an impactful pathogen of study. T. gondii is the causative agent of toxoplasmosis, an opportunistic infection that causes severe illness or fatality in immunocompromised individuals or pregnant women. The parasite possesses a very effective invasion strategy, allowing it to cross different tissue types to disseminate infection across the placental and blood-brain barrier. Although there are a few treatments for acute toxoplasmosis, these drugs can produce adverse side effects. These options are not effective against …

Spatial Ecology Of Mule Deer Migrations From Grand Teton National Park And The Teton Range, Justin K. Schwabedissen

All Graduate Theses and Dissertations, Fall 2023 to Present

The Greater Yellowstone Ecosystem hosts several of the longest, fully intact ungulate migrations remaining in the continental United States. However, expanding development and an increasing human footprint continue to truncate migratory routes. While the endpoints are often a seasonal range on protected lands, these migration corridors frequently cross other jurisdictional boundaries, including large tracts of private or multiple-use lands, with varying levels of protection. Thus, it is critical resource managers understand the dynamics of migratory movements to define population-level corridors and prioritize appropriate conservation strategies. Mule deer in Wyoming have been documented traveling long distances between summer and winter ranges; …

Chemical-Mediated Mate Attraction In Clover Root Curculio (Sitona Hispidulus F.), A Belowground Pest Of Forage Crops, Kristin Leutgeb

Undergraduate Honors Capstone Projects

Curculionid beetles are well known for their production of semiochemicals, including contact (e.g. cuticular hydrocarbons) and volatile pheromones that mediate conspecific attraction and mating. Clover root curculio (CRC; Sitona hispidulus) in particular is an emergent, soil-borne pest of significant concern to producers of alfalfa and other leguminous crops in the United States. Producers have few control options for CRC and a greater understanding of chemical-mediated attraction in this species can potentially improve the sustainability of its management. To examine which chemical cues are important for affecting the behavior of CRC and whether there are sex-based differences in response, I …

Evaluation Of The Effect Of A Commercial Lippia Origanoides Essential Oil Extract On Salmonella Serovar Enteritidis As A Natural Alternative To Antibiotics In The Poultry Industry, Abdiel Atencio

Graduate Theses and Dissertations

The purpose of the present research was to evaluate the bactericidal activity of a microencapsulated Lippia origanoides essential oils (LOEOs) against Salmonella Enteritidis (SE) in an in vitro crop assay and in a prophylactic broiler chicken model using three low doses of the product: 75 ppm, 150 ppm and 300 ppm. Two trials of each assay were conducted. Day-of-hatch male Cobb-Vantress broiler chickens were randomly allotted to one of four groups: 1) positive control group; 2) 75 ppm LOEOs group; 3) 150 ppm LOEOs group; 4) 300 LOEOs group. Chicks were fed and watered ad libitum in heated brooder batteries …