Life Sciences Commons^™

The Influence Of Wind Energy Development On Occupancy Of Medium And Large-Sized Mammals In South Texas, Elwynn Sherman

Theses and Dissertations

Conservation paradigms have shifted from single to multi-species approaches for assessing and conserving mammalian populations and the habitats that they occupy. The effect of wind turbine development is an important anthropogenic change to study due to the increasing demand for wind energy in Texas. In this study, I gathered remote camera trap data on medium and large-sized mammal populations in south Texas Tamaulipan thornscrub habitat. The objectives were to determine species presence, the effect of habitat characteristics and anthropogenic disturbances on species occupancy, and the effect of temperature on species detection. The results showed that distance from wind turbines did …

How Many Tiny Snails? Circumscription Of Three Species Of Pyrgulopsis (Mollusca: Gastropoda: Hydrobiidae)In Nevada Mountain Springs, Trenton Meadows

Theses and Dissertations

The springsnail genus Pyrgulopsis is one of the most diverse groups of freshwater gastropods in North America (Hershler, 2014), with many species displaying high levels of endemism (Hurt, 2003). This study attempts to circumscribe three putative species of springsnails: Pyrgulopsis serrata, Pyrgulopsis marcida, and a newly identified clade, referred to as Lineage C, from the Ruby Lake National Wildlife Refuge, Nevada, USA and nearby springs. Using an integrative taxonomic approach, we combined morphological, anatomical, and molecular data to examine species boundaries and evolutionary relationships.

Many lines of evidence were considered to determine species boundaries. Phylogenetic analysis of the mitochondrial …

The Effects Of Livestock On Mosquito Diversity And Abundance In Hidalgo County, Taylor Nicole Moya

Theses and Dissertations

Mosquitoes are detrimental to animals and threaten humans. More information is needed on how farm animal presence may impact mosquito abundance and diversity at farms. My goal in this study is to determine if there is any correlation between animal abundance or diversity on a farm and the abundance and diversity of mosquitoes collected. Hidalgo County, Texas, has a subtropical desert climate, ideal for mosquitoes. I hypothesized that the mosquito abundance and diversity indices would increase as the livestock abundance or diversity increases. Adult mosquitoes were collected using two CO2-baited light traps per farm from Spring 2022 to Fall 2022. …

Understanding The Influence Of Traffic And Noise On The Wildlife Community Surrounding Fm106 And Sh100 In South Texas, Anna Rose Mehner

Theses and Dissertations

In South Texas, highways create landscape fragmentation, habitat degradation, and result in wildlife vehicle collisions. Vehicle collisions are the highest known cause of mortality of the endangered ocelot (Leopardus pardalis), which led Texas Department of Transportation to install nine wildlife crossing structures (WCS) on Farm-to-Market 106 and five on State Highway 100. These highways are along Laguna Atascosa National Wildlife Refuge, which is the location of the southernmost breeding population of ocelots in the United States. Many other wildlife species including bobcat (Lynx rufus) and coyote (Canis latrans), are present along these highways and …

Structure Modifications And Alternative Monitoring Designs Of Wildlife Road Mitigation Structures, Madison T. Nadler

Theses and Dissertations

Wildlife mitigation structures are designed to keep animals off roadways while providing them safe passage to the other side and not impeding traffic flow. Camera traps are commonly used to assess the success of these mitigation structures, but there are downfalls to both the methods and structures. Alternative mitigation structure designs are needed to better prevent wildlife from accessing roadways in areas where they should be deterred. Additionally, traditional camera trapping methods do not accurately capture the full wildlife communities that may be utilizing these structures and other survey methods are needed, specifically aimed at small mammals, amphibians, and reptiles. …

Effects Of Metoprolol And Propranolol Beta-Blockers Mixture On Morphological And Physiological Responses In The American Oyster, Andrew Salinas

Theses and Dissertations

Beta-blockers are extensively used to treat human cardiovascular conditions yet pose significant risks to non-target aquatic organisms. This study aimed to investigate the effects of short-term exposure (one week) to a beta-blocker’s mixture (low-dose: 50 ng/L propranolol and 250 ng/L metoprolol, and high-dose: 250 ng/L propranolol and 650 ng/L metoprolol) in the American oysters. Histopathological assessments revealed structural damage to gills, connective tissues, and digestive glands in both low- and high-dose treatment groups. Additionally, glucose concentration and pH of the extrapallial fluid significantly declined in the high-dose treatment group. Hemocyte density within connective tissues increased proportionally with dosage. The beta-blocker …

Guiding Wildlife: Evaluating Wildlife Exit Designs And Sensor Lights For Safer Highways In South Texas, Rupesh Maharjan

Theses and Dissertations

Roadside exclusionary fencing is more prevalent on highways to prevent wildlife-vehicle collisions. Although it can mitigate wildlife road mortality by limiting their access to the road, it can also create a barrier for wildlife stranded within the right-of-way. In State Highway 100 of Texas, the Texas Department of Transportation installed ten wildlife exits to allow wildlife to escape the fenced roadway, and a pair of sensor lights on 13 wildlife guards (WGs) to scare off target species (bobcats and coyotes) from crossing the guards and accessing the roadway. In this study, the effectiveness of three wildlife exit (WE) designs were …

Effect Of An Anti-Hiv Polymer Based Nanoformulation On Immune Mediating Cells Within The Gut Associated Lymphoid Tissue And Its Behavioural Impacts, Blessed Ofori

Theses and Dissertations

This thesis investigates the therapeutic potential of nanoformulated antiretroviral therapy (NF cART) and its implications for HIV-associated chronic inflammation and neurobehavioral outcomes. In the first study, NF cART demonstrated enhanced efficacy in modulating inflammasome activation and reducing viral reservoirs in gut-associated lymphoid tissue (GALT) and the small intestine of HIV-infected humanized mice. Key markers of inflammation (NLRP3, Caspase-1, and IL-1β) and viral replication (LTR and p24 levels) were significantly suppressed with NF cART compared to conventional therapy, though residual LTR expression persisted in the small intestine. In the second study, nanoformulated Emtricitabine uniquely enhanced locomotor activity and reduced anxiety-like behaviors …

Implementing Organic Fertilization Practices To Improve Aloe Vera Growth And Soil Health In The Lower Rio Grande Valley, Isaiah Edward Jaramillo

Theses and Dissertations

Aloe vera (L.) (Aloe) Burm. f., is valued for its applications across the cosmetic, medicinal, and food industries due to its leaf gel. In the aloe industry, the extraction of gel from leaves generates significant quantities of organic waste, which presents an opportunity to repurpose this material as an amendment in aloe cultivation. While Aloe is renowned for its resilience, understanding the feasibility of using these organic shavings as a soil fertility amendment in aloe production is critical. This research aims to identify sustainable fertilization methods for Aloe that can maintain and/or improve crop yield while enhancing soil health. This …

A Nursery Study Of The Interplay Between Soil Texture, Rooting Space, And Nurse Plants On Seedling Growth And Root Development In Woody Species Of Tamaulipan Thornscrub, Lance I. Santos

Theses and Dissertations

Reforestation attempts in semi-arid regions are plagued with seedling mortality. Blanket greenhouse practices may not be optimal, in addition, commensalism interactions between nurse plants are considered. To better understand the effects of soil texture and nurse plant interactions on growth and drought tolerance, two experiments were developed. For soil texture, Border palo verde seedlings were grown in different-sized plant bands with three soil types. To observe the effects of nurse plants, an experiment using guayacan, was developed using Texas Ebony, as a leguminous nurse plant. Plants were also exposed to a drought experiment. The results suggest that some soil textures …

Examining Hispanic Beginning Farmers And Ranchers In The Rio Grande Valley Through A Community Capitals Framework, Perla Kimberly Schrock

Theses and Dissertations

While existing literature addresses the experiences of beginning farmers and ranchers (BFR), there is a notable gap in research focused on Hispanic beginning farmers and ranchers (HBFR). This study aimed at exploring the unique experiences of HBFR in a predominantly Hispanic region, the Rio Grande Valley (RGV), employed the Community Capitals Framework (Flora et al., 2016). I conducted 16 semi-structured interviews with HBFR and local nonprofit organizations and federal employees, complemented by participant observations. Through thematic and content analysis of the interview transcripts, findings revealed valuable insights into the livelihoods of HBFR. Despite HBFR facing significant challenges, this study demonstrated …

Assessing Cover Crop Adoption Factors In The Rio Grande Valley Through A Social-Ecological Perspective, Mackenzie Feldman

Theses and Dissertations

Reducing agriculture’s negative environmental impacts is crucial for mitigating climate change (White, 2021). Cover crops– non-cash crops grown to benefit subsequent cash crops– can slow erosion, improve soil health, enhance water availability, control pests, and increase biodiversity. Despite these benefits, adoption rates remain low, prompting the USDA and other organizations to fund research on increasing their use. Most studies focus on the Midwest and Northeast, and emphasize individual factors over the relationship between structural factors and individual factors that impact farmers’ decisions to adopt cover crops. This USDA-funded study begins to fill this gap by exploring social-ecological factors and how …

Assessing The Influence Of Native And Invasive Grasses On The Behavior Of Aedes Aegypti In South Texas, Emily Medelez

Theses and Dissertations

Invasive grasses in South Texas can have widespread negative effects, displacing native species, reducing biodiversity, and posing risks to public health. These grasses may flourish in moist, shaded environments, which not only support their growth but also creates habitats favorable for mosquito activity. This can increase the population and alter the behavior of mosquitoes, potentially raising the risk of disease transmission. In this thesis, I look at the behavior of mosquito species Aedes aegypti, primary vector of the yellow fever virus. I analyzed the influence of oviposition, flight and resting behaviors. I tested the relative attraction of Aedes mosquitoes …

Ecological And Pathological Applications Of The Heat Shock Response, Taylor Rae Stanley

Theses and Dissertations

The heat shock response (HSR) is a cytoprotective stress response pathway that regulates cellular proteostasis. The HSR is an evolutionarily conserved pathway that is essential for normal cellular functioning. Here, we explore the broad ecological and pathological impacts of the HSR. In an ecological context, we perform gene level analysis of the transcriptomes of two closely related sunfish. We found that the more invasive bluegill sunfish has gene expansions in two HSR gene families, the HSP70 family and the HSP90 family compared to the redear sunfish. These gene expansions were also observed in several other teleost fish species and were …

Tc-Ptp-Mediated Regulation Of P38 Mapk Pathway Promotes Uvb-Induced Apoptosis In Skin, Lindsey Susie Shim

Theses and Dissertations

T-cell protein tyrosine phosphatase (TC-PTP) is a non-receptor PTP that has been shown to have various roles in signaling pathways. Our previous studies have demonstrated that the TC-PTP deficiency in the epidermis can exacerbate hyperplastic response by inducing epidermal cell proliferation in response to tumor promoter TPA or UVB exposure. This implies that TC-PTP plays a tumor-suppressive role in the epidermis and provides protection against UVB radiation, which is well known to contribute to skin cancer development. The p38 mitogen-activated protein kinase (MAPK) is one of serine/threonine kinases that are activated through environmental stress including UVB. It has been demonstrated …

Investigation Of Reproductive Inhibition During Chronic Heat Stress In C. Elegans, Macy Makenna Nielander

Theses and Dissertations

Nearly all organisms experience heterogeneity in environmental conditions that can negatively impact fitness. A common adaptive strategy to reduce the impact of this stress is called facultative diapause, where development and reproduction are temporarily arrested to promote survival. Facultative diapause is characterized by three major criteria, the arrest must be (i) induced by an unfavorable environmental condition, (ii) reversible, and (iii) driven by genetically regulated mechanisms. The aim of this thesis was to determine whether chronic heat-induced inhibition of egg laying in Caenorhabditis elegans represents a novel form of facultative diapause. It was found that the inhibition of egg-laying is …

Soil Biogeography And Community Assembly In Polar Regions, Jesse Jorna

Theses and Dissertations

The polar regions provide community ecologists with natural microcosms, that include reduced species diversity, steep environmental gradients and limited human perturbance. Soil biodiversity in the polar regions is poorly understood, and the driving forces behind community compositions can range in scale from glacial forces 20,000 years ago to the impact of a researcher's footstep. Here, we present the results of an investigation of the driving factors behind biodiversity in Arctic and Antarctic soils, with specific attention to the role of community assembly processes. We suggest a framework for investigating the effects of inter-bacterial community processes like facilitation and argue for …

Human-Bear Conflict In North America (1880-2020): A Comprehensive Analysis Of Patterns, Outcomes And Interactions, Cody Robert Miller

Theses and Dissertations

Human-bear (Ursus spp.) conflict (HBC) is an important issue facing wildlife managers across North America. It is essential that we understand the factors associated with HBCs in North America so that wildlife managers can make appropriate, science-based recommendations about how to avoid, and if necessary, survive such incidents. To that end, we present this comprehensive analysis of > 2,100 HBCs in the United States and Canada, ranging from 1880 to the present. This analysis includes the three native North American bear species: black bears (Ursus americanus), grizzly bears (U. arctos), and polar bears (U. maritimus) and assesses the role that twelve …

Rare Sugars And Dairy Ingredients: A Synergistic Pairing For The Reduction Of Food Waste And Sugar Consumption, Melinda Michelle Moss

Theses and Dissertations

In the future, sustainability in the dairy industry will require creative and scale-able solutions for better utilization of the primary solid component in milk: lactose. One promising avenue of “up-cycling” underutilized lactose is converting it to valuable rare sugars. Rare sugars like D-tagatose and D-allulose are increasing in popularity extremely quickly. D-tagatose and D-allulose are hexose sugars, D-allulose being an epimer of D-fructose and D-tagatose an isomer of D-galactose. They have excellent functional properties in food systems with clean sweetness profiles similar to sucrose. Critically, they also have excellent nutritional characteristics, such as low caloric values and low glycemic indices. …

Investigating Secondary Metabolites Of Streptomyces And Bacillus Bacteria That Inhibit Colony Growth Of Pathogenic Potato Fungi (Colletotrichum Coccodes, Pythium Ultimum), Jacob R. Henrie

Theses and Dissertations

Potato (Solanum tuberosum) is a crucial global food crop, yet its production is threatened by fungal pathogens such as Pythium ultimum and Colletotrichum coccodes, which cause significant yield losses and impact tuber quality. In this study, we investigated the antifungal properties of various Streptomyces and Bacillus isolates against these pathogens. The Streptomyces isolates, known for their prolific secondary metabolite production, were selected for their varying efficacy against these fungi. Despite the anticipated potential, Streptomyces isolates exhibited limited antifungal activity against Pythium ultimum and only moderate activity against Colletotrichum coccodes. In contrast, Bacillus isolates, particularly B1, demonstrated strong inhibition of C. …

Preparation And Efficacy Evaluation Of Chicken Egg Yolk Sourced Igy Against The Venoms Of Cobra, Krait, Russell’S Viper, And Saw-Scaled Viper, Gayathri G

Theses and Dissertations

Envenomation resulting from snakebites is widely recognized as an alarming health risk in tropical and sub-tropical areas. The big four snakes including Naja naja, Bungarus caeruleus, Daboia russelli, Echis carinatus are responsible for most of the envenomation in India. The current therapy for snake envenomation is immunoglobulins, produced from serum or plasma of horses or sheep. To overcome the drawbacks of current antivenom, chicken egg yolk (IgY) antibodies have recently emerged as one of the most promising research avenues.

In this study, the efficacy of chicken egg yolk sourced antisnake venom (ASV) IgY against the big four venoms was evaluated …

Harvesting Health: The Role Of City Policy In Urban Agriculture And The Downstream Effects On Youth, Lesley Leake

Theses and Dissertations

Contextualizing environmental health within the socio-ecological framework, acknowledges the diverse factors at play in the environment-human dynamic. The research design, methods, and study populations of each chapter vary to match the socio-ecological level(s) of focus and reinforce the translational and interdisciplinary nature of this research. Chapter 2 examines the policy-supports for urban agriculture using a mixed-methods case-study of the City of Charleston, SC to understand how municipal policy (societal) impacts urban agriculture implementation (community) and what impact this has on residents (relationship and individual). Chapter 3 centers on the potential impact of urban farms (community) and their programming (community and …

Impacts Of Ing4-Deficiency On Hematopoietic Stem And Progenitor Cells & Characterizing The Concerns Of Novice Stem Graduate Teaching Assistant, Georgina Alice Anderson

Theses and Dissertations

The hematopoietic compartment is tasked with the establishment and maintenance of the entire blood program in steady-state and in response to stress. Key to this process are hematopoietic stem cells (HSCs), which possess the unique ability to self-renew and differentiate to replenish blood cells throughout an organism’s lifetime. Recent work has illustrated the vast mechanisms involved in regulating stress-induced hematopoiesis, including cytokine-mediated lineage bias, gene signature changes in aged HSCs associated with chronic inflammation, the impact of clonal hematopoiesis and stress tolerance. Inhibitor of Growth 4 (Ing4) has been identified as a critical regulator of HSC homeostasis. We show that …

Plankton Dynamics In A Temperate Estuary:Size Structure And Trophic Implications, Nayan Mallick

Theses and Dissertations

Estuarine ecosystems provide goods and services to around 45% of the entire human population. In recent times, these ecosystems have been severely affected by multiple stressors such as pollution, eutrophication, harmful algal blooms, sea level rise, and, most importantly, climate change. Increasing temperature associated with climate change can have pervasive impacts throughout the ecosystem’s functions and processes. Plankton, a conspicuous member of estuarine food web, are among the first to respond to the changes in temperature due to their high sensitivity to changing environmental conditions.

In this dissertation, I investigated the plankton dynamics in an estuarine ecosystem through a combination …

Deciphering Evolutionary Co-Option By Studying The Origin Of Self-Fertility In Caenorhabditis Nematodes, Jonathan P. Harbin

Theses and Dissertations

In my research, I examined the characteristics of male and female sex-determination mutants in C. nigoni and investigated the regulatory pathway they define. This work tested whether flexibility in the sex-determination pathway was a preexisting condition that favored the origin of self-fertility in Caenorhabditis. Furthermore, I developed an approach for using interspecies hybrid mutants to assess the robustness of the C. nigoni pathway. My findings showed that the C. nigoni pathway is highly robust and canalized, suggesting that changes leading to self-fertility must have involved the impairment of this canalization in the germ line, to allow eventual alteration of germ …

Discovery Of Small Molecules To Alleviate Heart Disease-Induced Proteinopathy And Proteotoxicity Characteristic Of Alzheimer’S Disease, Nirjal Mainali

Theses and Dissertations

Cardiovascular disease (CVD) is the leading cause of death in the world and in the United States. Reduced cardiac output due to CVD has been previously associated with decreases in systemic and cerebral perfusion. Cerebral hypoperfusion increases the risk of Alzheimer’s disease (AD), accompanied by accumulation of aggregates that feature Aβ amyloid and hyperphosphorylated tau. Protein aggregation is a shared hallmark of aging and neurodegenerative diseases. We previously reported elevated aggregation in hearts of hypertensive and aged mice and now find that aggregation is induced in hearts and brains of male C57BL/6 mice after transient ligation of the left coronary …

Dissecting The Interplay Of Protein Synthesis And Degradation Pathways In Cellular Adaptation To Stress, Brittany Friedson

Theses and Dissertations

Adaptation to stress requires cells to reprogram transcription, translation, and proteolytic pathways. Although much is known about the response of each program, it remains unclear how they coordinate following stress. My studies in S. cerevisiae identified the Cdk8 kinase module (CKM) of the Mediator complex as a new player in coordinating these processes. It is well established that the CKM consists of four highly conserved proteins (cyclin C, its cognate kinase Cdk8, and two structural proteins Med12 and Med13) and predominantly represses a subset of stress responsive genes in yeast. We demonstrated for the first time that the CKM also …

Developing Coexpression Systems To Introduce Hydroxyproline Into Protein Engineered Collagen Peptides Utilizing Hydroxylase From Acanthamoeba Polyphaga Mimivirus, Jennifer Soldatich

Theses and Dissertations

A major challenge of developing collagen mimetic peptides (CMPs) by bacterial expression is to include hydroxyproline for biomedical applications. Coexpression of Prolyl-4-hydroxylase from A.mimivirus with CMPs was investigated. Additionally, four expression designs were created for potential applications in mammalian cells to utilize their natural ability of proline-hydroxylation by post-translational modification.

Horizontal Gene Transfer In Intergenomic Conflicts Between Bacteria And Their Genetic Parasites, Pavithra A.S

Theses and Dissertations

Bacteria are constantly infected by obligate acellular genetic parasites, such as plasmids and phages. The genetic conflicts between bacteria and their parasites, aggravated by horizontal gene transfer, exert significant ecological and evolutionary pressure on their respective genomes. The eco-evolutionary significance of parasite-derived elements on bacterial genomes is not well understood.

This study explored the genomics of plasmid-derived genetic elements such as antimicrobial resistance genes (ARGs), type II endonuclease toxin-antitoxin systems (TAs) and endonuclease colicin-like bacteriocin (CLB) operons, and phage-derived prophages of Escherichia coli using bioinformatics and developing novel hybrid agent-based models. We sequenced eight E. coli isolated from local wastewater …

Pm2.5 In The Respirable Air A Threat To Heart Health Investigating The Influence On Cardiovascular Performance And Unmasking The Potential Strategies For Cardio Protection, Bhavana Sivakumar

Theses and Dissertations

Air pollution, characterized by the presence of harmful substances in the atmosphere, represents a significant environmental and public health challenge impacting millions worldwide. The World Health Organization (WHO) reports that approximately 90% of the global population resides in regions where air pollution surpasses the recommended thresholds for healthy air quality. Within the realm of air pollution, the composition of particulate matter emerges as a pivotal consideration, particularly regarding PM2.5, comprising minute particles originating from diverse sources such as combustion processes, industrial operations, and natural phenomena like wildfires and dust storms. PM2.5 exhibit a range of chemical and physical attributes contingent …