Life Sciences Commons^™

Population Genetics Among Rhipicephalus Sanguineus Ticks In The Lower Rio Grande Valley, Bianca Liana Guerra

Theses and Dissertations

Rhipicephalus sanguineus is a common tick species in the lower Rio Grande Valley of both human and veterinary concern. Two lineages of R. sanguineus have been described across the United States known as the tropical and temperate lineage. Both lineages can be differentiated morphologically, genetically, biologically, and by vector competence. The species name for both lineages has not been well established therefore this thesis will utilize their widely used identification. Both lineages have been identified in Texas. While the distribution of these lineages has been well-defined in some regions across the world, recent studies have observed sympatric populations in certain …

Study Of Population Dynamics Of Sugarcane Aphid (Melanaphis Sacchari) In Rio Grande Valley, Texas, Neetu Khanal

Theses and Dissertations

Chapter 1: This chapter incorporates detailed information about the biotype concept, aphids, their types and their biotypes, importance of studying insect biotypes and their role in mediating host plant defenses.

Chapter 2: This chapter explains in detail about the biology, biotypes, feeding behavior, damage, and economic loss caused due to sugarcane aphid infestation. This chapter further elaborates on the need for studying population level differences and justifies the objectives and significance of this research study.

Chapter 3: This chapter provides information about the comprehensive work done on three different populations of sugarcane aphid collected from three different locations in Rio …

Biological Optimization Of Polymer-Based Antiretroviral Drug Towards The Gut-Associated Lymphoid Tissue (Galt), Arkajyoti Paul

Theses and Dissertations

Background: Combination antiretroviral therapy (cART) has significantly decreased the disease mortality associated with HIV-1 but does not efficiently reach the HIV reservoir organs such as GALT. In this regard, the present study determined the efficacy of the polymer-based nanoformulations using F127 alone and in combination with L61 to encapsulate three clinically available cART drugs such as Emtricitabine (FTC), Tenofovir Disoproxil Fumarate (TDF), and Dolutegravir (DTG) in in vitro and in vivo system. Methods: The selected formulations were studied for their biological and chemical characterization towards human cell line viz. Caco-2 and Human peripheral blood mononuclear cells (PBMC) and in vivo …

Road Mitigation Structure And Road Effect Zone Impacts On Rodent Community Composition, Activity, And Predator-Prey Dynamics In South Texas, Adam F. Sanjar

Theses and Dissertations

The effects of road mortality mitigation structures on rodent activity and rodent community composition are not fully understood, both on the regional scale of south Texas and in the broader field of road ecology. This is primarily due to the low conservation priority of most rodent species and the difficulty of noninvasively surveying for rodents effectively. This thesis focused on characterizing how rodents were impacted by both roads and mitigation structures in south Texas, and if rodents are a significant factor to consider when studying the road ecology of rodent predators in south Texas, particularly ocelots, bobcats (Lynx rufus …

Structural And Functional Insight Of Helicobacter Pylori Translation Initiation Factor If1 (Hpif1) In Protein Biosynthesis And Rational Design Of New Antimicrobial Candidates, Asif Shahriar

Theses and Dissertations

Helicobacter pylori (H. pylori) is a Gram-negative bacterium that colonizes the human gastric mucosa and is associated with peptic ulcer disease and gastric cancer. Bacterial protein synthesis is a fundamental metabolic process occurring in all bacteria and is a validated target of antibiotics; however, the precise structural mechanism of H. pylori protein biosynthesis remains unknown. Protein synthesis contains four stages, and translational initiation is the most important and highly regulated critical step, involving three initiation factors (IF1, IF2, IF3) and other key components. IF1 plays a vital role in regulating this step by binding to the 30S ribosomal subunit cooperatively …

Red Snapper Abundance, Growth, And Movement At Different Structural Configurations In The Rio Grande Valley Artificial Reef, Marybeth J. Weihbrecht

Theses and Dissertations

The Rio Grande Valley (RGV) artificial reef was built with the goal of providing habitat for reef fish at various life stages. This study used fish trapping to analyze red snapper and grey triggerfish size and abundance in the RGV reef. Mark-recapture of red snapper was utilized to determine growth, movement, and site fidelity within the reef. Nine configurations of patches consisting of varying combinations and densities of concrete pyramids and low-profile modules were surveyed, as well as additional sites of cinder block palettes and concrete railroad ties. Red snapper and triggerfish abundance per trap hour varied significantly by site …

Identifying Direct Foxo Targets Through Chromatin Immunoprecipitation Assays With Sequencing, Alma Lopez

Theses and Dissertations

Glioblastoma Multiforme (GBM) and basal-like breast cancer (BBC) are aggressive cancers associated with poor prognoses. Basal-like breast cancer (BBC) and glioblastoma multiforme (GBM) are poor prognosis cancers that lack effective targeted therapies. A deregulation of FOXOs has been linked to cancer, as they regulate the expression of genes involved in multiple cellular processes. Canonically, the FOXO family of proteins is generally considered tumor suppressors, but evidence suggests that they may be involved in cancer metabolism as well as angiogenesis. Research in our lab has found that these factors play a role in glycolysis and the developmental WNT pathway. Here we …

Estimating The Functional Consequences Of Intra-Specific Trichome Variation Of Tomato, Solanum Lycopersicum On The Specialist Herbivore, Manduca Sexta, Satinderpal Kaur

Theses and Dissertations

Chapter 1: Plants have a wide array of defenses against herbivores and hence they must confer trade-offs between growth and defense related traits. By using Solanum as a model genus, the major plant defense fitness trade-off hypotheses are reviewed in this chapter along with their assumptions and examples.

Chapter 2: This chapter provides an overview of the enormous intra-specific diversity in trichome morphology in tomato, Solanum lycopersicum. Also, the trichome sub-types are analyzed for the variations in density and dimensions in 10 varieties of tomato by using desktop scanning electron microscope.

Chapter 3: This chapter examines the functional consequences …

Activation Of Opa1 Processing In Differentiated Myoblast Cells, Omar Agustin Carrillo

Theses and Dissertations

Mitochondria are eukaryotic cellular organelles that play a role in energy production, apoptosis, integrated stress response, and aging. Mitochondrial dynamics is the physical fusion (interconnection) and fission (fragmentation) of mitochondria within a cell and tightly regulates mitochondrial functions. Optic atrophy 1 (OPA1) is a dynamin-related GTPase located in the inner mitochondrial membrane, and is responsible for inner mitochondrial membrane fusion. OPA1 exists in five isoforms, the two fusion-active long OPA1 (L-OPA1) and the three fusion-inactive short OPA1 (S-OPA1) isoforms. When the transmembrane potential (∆ψm) is aggravated, the inner membrane metalloprotease OMA1 is activated, causing the complete cleavage of L-OPA1 to …

Dopamine Dysregulation In Antiretroviral Drugs Treated Neuronal Cells, Andrea S. Bustos

Theses and Dissertations

According to the world health organization (WHO), 37.7 million people worldwide in 2020 were living with the human immunodeficiency virus (HIV-1). In the US, combination antiretroviral therapy (cART) drugs have shown effectiveness in combating HIV-1 infection. As a result, cART has prolonged the lifespan of people with HIV aiding these patients to age with the virus. Clinical evidence has established the long-term effects of cART in the aging population causing neuropsychiatric disorders such as depression. However, the underline molecular mechanism that cART induces depression-related neurodegeneration has not been established. This study will pursue a dopamine (DA) dysregulation marker in cART …

Understanding The Developmental Regulation Of Opa1 Processing In C2c12 Myoblasts, Harpreet Kaur

Theses and Dissertations

Mitochondria is an energy-producing organelle in the cell that accept electrons from the Krebs cycle to generate energy in the form of ATP by oxidative phosphorylation. Two mitochondrial aspects, bioenergetics and dynamics are critical for energy balance and cellular stress responses. Mitochondrial dynamics refers to the balance between mitochondrial fusion (mitochondrial biogenesis) and mitochondrial fission (mitochondrial fragmentation). Cellular stress conditions that lead to dissipation of transmembrane potential (Δψm) trigger the activation of an IMM protein, OMA1, a metalloprotease that leads to processing of another IMM protein, optic atrophy-1 (OPA1) that mediates IMM fusion. Persistent stress primes the mitochondria to mitophagy …

Assessing The Role Of Hybridization In The Evolution Of Two Common Lineages Of Lichen-Forming Fungi, Rachel Keuler

Theses and Dissertations

Once thought to be an evolutionary dead-end, hybridization is now being detected in genomes across kingdoms, perhaps even playing an integral role in evolution. In chapter 1, I investigated the potential influences of hybridization on the evolution of a group of vagrant, asexual species in the Rhizoplaca melanophthalma species group. I sequenced the mitochondrial and nuclear genomes of 55 specimens and found well-supported nuclear phylogenies of both datasets. There were, however, multiple instances of discordance between the mitochondrial and nuclear trees, which can be caused by hybridization. PhyloNet and ABBA-BABA also detected widespread hybridization among this group. In chapter 2, …

Superabsorbent Polymer Use In Rangeland Restoration, Shannon V. Nelson

Theses and Dissertations

Soil moisture deficits often hinder rangeland revegetation efforts. Due to sheer numbers and germination timing, invasive annual species can easily outcompete those of desired seeded species for resources, including water. One way to increase seedling establishment may be to increase the amount of water available to seeded species. Superabsorbent polymers (SAPs) can absorb and release hundreds of times their weight in water and slowly release it. Concentrated SAP bands at or near seedling rooting depth may act as a soil water reservoir for germinating seedlings and increase rangeland seedling establishment. The objective of these studies was to evaluate the effect …

Studies On Osh6 And Its Pro-Aging Mechanisms, Nazneen Begum

Theses and Dissertations

The target of rapamycin complex 1 (TORC1) is a master regulator of cell growth as well as a negative regulator of longevity. A recent study in yeast showed that the vacuolar TORC1 stimulates protein synthesis and cell growth while the endosomal TORC1 inhibits autophagy, a pro-longevity process. Since late endosome frequently exchanges membranes with vacuoles, the spatial dissection of TORC1 raises an interesting question as to how to inhibit the endosomal TORC1 and boosts the vacuolar TORC1 to extend the health span. In my thesis, I employed a longevity mutant that mildly up-regulates Osh6 (PERG6-OSH6) to address this question. I …

Migration Of Elk (Cervus Canadensis) And Barriers To Movement, Levi Watkins

Theses and Dissertations

Movement patterns of animals are varied, complex, and can be influenced by environmental and anthropogenic factors. One form of animal movement, migration, is influenced by environmental factors that alter the timing, duration, intensity, and likelihood of migration. Additionally, features of the landscape, both natural and anthropogenic, can alter how animals move through their seasonal and home ranges. Movement patterns can be impeded or prevented by features such as railroads, rivers, and roads. Here we explore characteristics of elk (Cervus canadensis) migration by evaluating the strategies of migration exhibited and the factors that influence migration of elk in central and eastern …

Overcoming Barriers To Native Species Restoration Using Gibberellic Acid And Fungicide Seed Coatings, Amber Jo Johnson

Theses and Dissertations

Many barriers can limit restoration success. In the first chapter of this thesis, the barrier of strong seed dormancy is addressed. While dormancy benefits the species' long-term survival, it can present a challenge within a restoration scenario where rapid establishment is required. Soaking seeds in gibberellic acid (GA3) can overcome dormancy. An easier and potentially more effective method to apply this hormone is to coat seeds with a GA3-impregnated polymer, which provides a slow release of the hormone. Seed dormancy can also be mitigated by creating a favorable microsite with increased soil moisture. We compared the emergence and establishment of …

Volatile Organic Compound Identification Using Metal Oxide Sensors And Machine Learning, Hunter Tiner

Theses and Dissertations

Volatile Organic Compounds (VOCs) are emitted gases that include many chemicals that can be created by biological processes or the byproduct of industrial processes, and can be present in a variety of pollutants. VOCs can cause a variety of ailments in humans and animals, and are expressed in plants as a way of signaling damage or the presence of pests. In this Thesis, an Internet of Things (IOT) E-nose device is outfitted with a gas array of eight Metal Oxide Semiconductor (MOS) type gas sensors, which are sensitive to a broad range of VOCs, yet lack selectivity and are unable …

Development Of A Valid And Reliable Survey To Assess Personal, Behavioral, And Environmental Factors Surrounding Food Insecurity In A College Population, Jennette Kilgrow

Theses and Dissertations

Objective: The aims of our present study were to develop a valid and reliable survey framed around the social cognitive theory, which would evaluate internal and external factors associated with food insecurity from the student's perspective, and to test the survey with a multi-state population. Design: The College Perspectives around Food Insecurity (CPFI) survey was developed through several revision and improvement steps using a mixed methods approach. In Phase 1 (2018-2019), data were translated into survey items and assigned to a theoretical concept (personal, behavioral, or environmental) in the social cognitive theory. In Phase 2 (2019-2020), content validity testing occurred …

Descriptions, Ecological Associations And Predictive Species Distribution Models Of New Species Of Psilochalcis Kieffer (Hymenoptera; Chalcididae) Occurring In Utah's Eastern Great Basin, Mark J. Petersen

Theses and Dissertations

The genus Psilochalcis, of the Family Chalcididae, was originally described in 1905 by Kieffer. Mainly considered an Old-World taxon, the first North American Psilochalcis were not identified until 1981 by Grissell and Schauff. Little is known about the species distributions, biologies and ecological relationships of these parasitic wasps. This dissertation describes research conducted in central Utah setting arrays of Malaise traps in 4 different habitat types common to the Great Basin at three separate locations. A result of this sampling revealed a high abundance of multiple species of Psilochalcis wasps, particularly from one location and two habitat types. Chapter 1 …

Data Mining The C. Elegans Transcriptome For Regulators Of Longevity And Aging: A Multiple-Analysis Approach, Jay Johnson

Theses and Dissertations

Transcriptional profiling is extensively used to produce a snapshot of gene and pathway activity in a sample at a specific point in time, by utilizing high-throughput sequencing to quantify total gene expression at the transcript level. An isogenic panel of C. elegans longevity mutants, supplemented with a panel of RNAi gene-knockdowns known to convey longevity, both at an assortment of ages, was analyzed in an effort to elucidate transcriptional signatures of both longevity and aging in nematodes. Included in this panel was age-1(mg44) F2, a well-documented mutant characterized by extreme longevity. Genes that were highly differentially expressed between age-1(mg44) F2 …

Prevalence And Predictors Of Intern-Related Burnout In Dietetics Preceptors, Holly Hopkins

Theses and Dissertations

Dietetics preceptors are at risk for abandoning the role of preceptor because of potential burnout. Quantifying the prevalence of burnout and identifying the predictors of burnout can help key stakeholders identify and implement strategies that prevent or mitigate burnout in dietetics preceptors. The purpose of this study was to determine the prevalence of intern-related burnout in dietetics preceptors and to identify the predictors of this burnout. This study used a cross-sectional study design. A survey instrument that included burnout and precepting measures, and items about the respondents’ personal and work characteristics was distributed to a random sample of 10,000 dietetics …

Forest Understory Plant Community Response To Prescribed Fire And Mechanical Thinning Treatments, Noelle V. Zenger

Theses and Dissertations

Much of the biodiversity in a forest comes from the understory vegetation. However, centuries of fire suppression in the western United States have made human-implemented disturbance necessary for reinstating natural disturbance cycles. However, the mechanical thinning and prescribed burning treatments used by land managers may differentially affect the response of the understory community. This study aimed to compare how prescribed fire and mechanical thinning treatments, with the size and severity of those treatments, affect understory plant communities in aspen-conifer forests over time. We sampled the understory community in burned, mechanically thinned, and untreated forest stands one, three, or five years …

A Comparison Of Kid Goat Lipase And Microbial Lipase On The Development Of Cheddar Cheese Flavor, Reece H. Larsen

Theses and Dissertations

Background: Manufacturers continue to look for methods to save time in aging cheese. Complex reactions occur during cheese ripening that produce characteristic flavors and aromas. The addition of exogenous lipase enzymes is one accelerated ripening method that has been studied. Our objective was to document and compare the flavor profiles of cheddar cheeses created with either microbial lipase or animal lipase. Materials and Methods: The experiment followed a conventional formulation to create experimental batches of cheddar cheese. Kid goat lipase and three microbial lipase treatments were compared against a control. Other animal lipases were evaluated in preliminary research but were …

Dopamine D2 Receptors As A Peripheral Biomarker For Brain Dopamine Levels, Christina Small

Theses and Dissertations

The ability to objectively index dopamine (DA) levels in the brain has the potential to revolutionize the field of neuropsychopharmacology, as having a peripheral biomarker of brain DA would enable the objective monitoring of the progression of Parkinson's disease (PD) and other DA-dependent psychiatric states. Of particular relevance to commercialization, it would provide an objective measure of treatment efficacy. We used a DA-depletion approach to determine if peripheral D2Rs are a biomarker for brain DA; mainly, the 1-methyl-4-phenyl-1,2,3,6-tetrahydropyridine (MPTP) neurotoxin model and PD subjects, which are well-known models of DA depletion in the midbrain of rodents and humans, respectively. Dopamine …

Habitat Effects On Scorpion Densities And Microhabitat Use By Centruroides Vittatus And Vaejovis Waueri In South Texas, Jonathan Beltran

Theses and Dissertations

Co-existence between Centruroides vittatus and Vaejovis waueri is influenced by environmental factors that shape their habitats. Differences in surface activity frequency between the two species suggest differential microhabitat use. The observed frequency of scorpions using microhabitats in the Martinez Ranch and La Union Ranch were not significantly different from the expected frequencies. Frequency of scorpions observed using microhabitats in La Union South was significantly different from the expected frequency (P<0.001). Microhabitat use of catclaw was lower than expected and higher than expected for other vegetation. Conditional comparisons of microhabitats were significantly different among habitats (P<0.001), size classes were significantly different among microhabitats (P<0.001), and size classes were significantly different among habitats (P<0.01). Microhabitat use by scorpions on the ground was higher among all habitats. Scorpion use of ground and grass were different among size classes. Size class I-II scorpions had a higher frequency than size class III. Scorpion density for C. vittatus was significantly different among habitats (P<0.0001) and scorpion density for V. waueri was significantly different among habitats (P<0.0001). Centruroides vittatus was significantly higher in the Martinez Ranch and in La Union South. Vaejovis waueri was significantly higher in La iv Union South. Associations between plant densities and scorpion size classes were tested. Plant densities had a significant association with C. vittatus size classes I and II in the Martinez Ranch. Association between plants had a significant correlation with C. vittatus size classes I and IV in La Union Ranch. Association between plants had a significant correlation with V. waueri’s total density. These associations may suggest plant densities may have a synergistic effect on scorpion densities. Soil type composition for the different habitats was hypothesized to influence scorpion densities. Maps for each site were created to show soil type compositions. Soil type findings suggest that La Union South had the soil types with the lowest soil strength. Vaejovis waueri was shown to have a higher density in La Union South where soils are sandier. Results indicate that co-existence between C. vittatus and V. waueri is possible because competition is low through minimal overlap in microhabitat use and intraguild predation avoidance.

Halophilic Genes That Impact Plant Growth In Saline Soils, Mckay A. Meinzer

Theses and Dissertations

Many plants are highly sensitive to salt in the soil, and their growth and yield can be greatly hindered by as little as less than 1% salt concentration in the soil. Additionally, soil salinity is a growing issue globally and affects significant areas in Utah. Halophytes are plants that are adapted to grow in saline soils and have been widely studied for their physiological and molecular characteristics, but little is known about their associated microbiomes. Bacteria were isolated from the rhizosphere and as root endophytes of Salicornia rubra, Sarcocornia utahensis, and Allenrolfea occidentalis, three native Utah halophytes. Several strains of …

Utilizing Isothermal Titration Calorimetry To Measure Β-Galactosidase Activity In Dairy Products, Tyler Ronald Jarrard

Theses and Dissertations

The dairy industry uses enzymes to make cheese, alter product flavor, and eliminate lactose. The activities of these enzymes have been measured in clear buffered solutions, but because of the limitations of spectrophotometric methods, enzyme activities have not been measured in opaque or colored dairy products where they are used. Isothermal titration calorimetry (ITC) can be used to determine reaction kinetics in opaque and colored solutions by measuring the heat rate from enzyme-catalyzed reactions as a function of time. This study used ITC to measure β-galactosidase activity in opaque solutions of milk, sweet whey, sweet whey permeate, acid whey, and …

Development And Validation Of A Spanish Nutrition Screening Tool For Hispanic American 3 To 5-Year-Olds, Denisse Arias Olivas

Theses and Dissertations

Latinos comprise 18.9% of the population in the United States and are the largest and fastest growing minority group. Obesity prevalence was 26.2% among Hispanic children compared to 16.6% among non-Hispanic White children. The obesity epidemic among Latino children has been growing rapidly over the past three decades. Multiple barriers, such as lack of culturally appropriate screening tools, language, and lack of access to nutritional assessment and expert consultation, prevents screening of Latino children and further nutritional guidance. For this reason, prevention efforts such as the use of nutritional screening tools is required for early intervention, more so with populations …

Real-Time Imaging And Measurement Of Compartmentalized Redox Shifts Using Novel Redox-Sensitive Biosensors: Implications In Developmental Toxicology, Brandon Mitchell Davies

Theses and Dissertations

Glutathione (GSH) is a small antioxidant in the body and exists in large quantities compared to other antioxidants. The GSH redox state (Eh) helps developmental processes, however, when the GSH Eh is disrupted, cells may undergo significantly poor developmental pathways, possibly leading to long-lasting damages. Similarly, NADPH and Thioredoxin redox states can have a major impact on cellular function, viability, and response to both endogenous and exogenous toxicants. Subcellular, compartmentalized redox environments during normal or perturbed situations, specifically in the cytosol, mitochondria, and nucleus, are not well understood. Here, using the P19 neurogenesis model of cellular differentiation, the kinetics of …

A Comparison Of The Vascular Response To Acute Sauna Heating In Young And Middle-Aged Adults, Olivia Kathryn Leach

Theses and Dissertations

BACKGROUND: Age-related declines in endothelial function have been well documented with larger declines observed in middle-aged. Passive heat exposure has been shown to be a promising method to improve vascular endothelial health, with sauna specifically being linked to reduced risk of cardiovascular disease. Increases in blood flow and shear rates associated with heat exposure are often considered to have a major influence on the observed improved endothelial function following heat exposure. The magnitude of these changes in response to sauna have not yet been defined. Therefore, the purpose of this study is to quantify and compare the vascular response to …