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Urban-Rural Differences In Lifespan Variation In The United States, Benjamin H. Walker

Theses and Dissertations

Since the mid-1980s, mortality rate improvements in urban areas have outpaced those in rural areas, leading to substantial urban-rural disparities in mortality. Research on urban-rural mortality disparities has focused exclusively on differences in mortality between urban and rural areas and has not examined differences in the amount of inequality in the length of life within these areas. Lifespan variation is an important dimension of health inequality that complements traditional metrics of mortality (i.e., mortality rates and life expectancy) by indicating the amount of inequality of lifespans within a population. This dissertation provides several contributions to our understanding of urban-rural differences …

Using A Systemic Skills Model To Build An Effective 21st Century Workforce: Factors That Impact The Ability To Navigate Complex Systems, Morteza Nagahi

Theses and Dissertations

The growth of technology and the proliferation of information made modern complex systems more fragile and vulnerable. As a result, competitive advantage is no longer achieved exclusively through strategic planning but by developing an influential cadre of technical people who can efficiently manage and navigate modern complex systems. The dissertation aims to provide educators, practitioners, and organizations with a model that helps to measure individuals’ systems thinking skills, complex problem solving, personality traits, and the impacting demographic factors such as managerial and work experience, current occupation type, organizational ownership structure, and education level. The intent is to study how these …

Description Of The Conjunctival Microbiome Of Normal Non-Brachycephalic Dogs And The Effects Of Antiseptic Preparation, Lindsay Seyer

Theses and Dissertations

Surgical preparation reduces commensal bacterial load. Currently, no standardized preoperative ocular preparation method in the dog has been reported. Previous studies use culture-based methods to determine commensal bacterial populations. Recent reports suggest that high-throughput sequencing may be superior to culture techniques to determine bacterial communities in the eye and other tissues. The goal of this study was to describe the conjunctival commensal ocular microbiome and bacterial community using DNA sequencing and aerobic cultures of six normal, healthy dogs and investigate the short and long-term effects of an antiseptic protocol on the ocular microbiome. Samples were obtained prior to, immediately following, …

Implementation Of Teach-Back For Discharge Teaching In A Critical Access Hospital: A Quality Improvement Project, Katie Beth Notch

Theses and Dissertations

A lack of comprehension of discharge instructions may cause high readmission and emergency room revisit rates for organizations. At the project site, there was no current evidence-based practice to ensure patient comprehension of discharge instructions. The purpose of this quantitative, quasi-experimental quality improvement project was to determine if the implementation of the Institute for Healthcare Improvement (IHI) Always Use Teach-Back Toolkit would impact emergency room revisit rates among adult medical-surgical patients in a critical access hospital in rural Minnesota over four weeks. Afaf Meleis’ transitions theory and the Iowa model for evidence-based practice were the scientific underpinnings of the project. …

Cyanobacteria And Phytoplankton Responses To Nutrients In Deep-Water Montane Reservoirs, Madeleine Paige Malmfeldt

Theses and Dissertations

Mountains play an important role in providing water resources from snow and ice to downstream urban population centers. In Utah, USA, nearly 86% of the state's population resides in the rapidly growing urban corridor along the Wasatch Front. Water along the Wasatch Front is stored in several deep reservoirs in the Provo River Watershed. Additions of nutrients, into these reservoirs, may stimulate the growth of primary producers (e.g., total phytoplankton and cyanobacteria) potentially attenuating water quality. To determine the influence of nutrients on primary producers in the Provo River's reservoirs, identify whether cyanobacteria are transported downstream, and quantify nutrient thresholds …

Understanding Factors Influencing Seed Germination Of Seven Wildflowers In Sub-Alpine Ecosystems, Alyssa Joy Brown

Theses and Dissertations

This thesis explores the seed germination of seven wildflowers native to sub-alpine ecosystems. Wildflowers are an essential functional group in native plant ecosystems. Also known as forbs, these plants offer a myriad of benefits in addition to being aesthetically pleasing. They provide habitats for anthropods and small mammals, support native pollinator populations, and grow well with other plant functional groups (especially perennial grasses and shrubs). Healthy plant communities make use of the limited resources in our native ecosystems, competing with invasive species that can otherwise dominate the landscape. Germination involves the transition from seed to an actively growing plant. Following …

Investigating The Influence Of Available Drinking Water On Wildlife In Utah's West Desert, Danielle K. Finlayson

Theses and Dissertations

The availability of water is a limiting resource for many wildlife species in arid and semi- arid environments. Free water is essential for critical life stages for numerous species, including migration, reproduction, survival, and habitat selection. Riparian areas in the desert occur relatively infrequently, but support a disproportionally large percentage of plant and wildlife species found in arid environments. Our study covered two aspects of water use in the west desert of Utah. The first was assessing the impacts of nonnative ungulates (specifically feral horses and cattle) on natural springs, and how they influenced water quality, vegetation, and wildlife diversity …

Identifying Sinorhizobium Meliloti Genes That Determine Fitness Outcomes, Alexander B. Benedict

Theses and Dissertations

The remarkable metabolic capacity of the soil-dwelling bacterium Sinorhizobium meliloti is encoded on its three circular replicons: the chromosome and two large megaplasmids, pSymA and pSymB. Despite making up 45% of the genome, the pSymA and pSymB megaplasmids can be cured from S. meliloti. This unique attribute provides an opportunity to study the essentiality of chromosomal genes in the presence or absence of nearly half the genome. By interrogating chromosomal genes via massively parallel transposon insertion sequencing (Tn-seq) in the presence and absence of pSymA and pSymB, we identified 307 genes as being essential for viability regardless of the genomic …

Increasing Total Lipid Content In Pennycress ( Thlaspi Arvense L. ) Utilizing Crispr-Cas9 And Transgenic Approaches, Damiano Marchiafava

Theses and Dissertations

Thlaspi arvense (pennycress) is a member of the Brassicaceae family currently under development as an oilseed winter cash cover crop for the U.S. Midwest. Planted in the fall at the time of corn or soybean harvest, pennycress establishes vegetative leaves before going dormant for the winter. Pennycress plants then flower in early spring and mature in mid May to early June in time for seed harvest followed by planting soybeans or corn. Hence, pennycress along with corn and soybeans can constitute e.g. a corn-pennycress-soybean rotation resulting in the production of three crops in two years. The winter annual life cycle …

Saprotrophy Among Endophytic Fungi, Emily Marissa Weatherhead

Theses and Dissertations

Endophytic fungi have been found in every terrestrial plant investigated thus far. They can receive nutritional benefits from their host tissues. Two major modes of nutrition for endophytic fungi include biotrophy and saprotrophy. In chapter 1, I set out to determine whether endophytic fungi isolated from Quercus gambelii in Utah, USA were capable of saprotrophy and, if some were, how much variation in saprotrophic ability exists among them. Because saprotrophy requires moisture and, in Utah, moisture is largely unavailable outside winter and early spring, in chapter 2 I set out to determine if any of our isolated endophytic fungi were …

Small Mammal Community Ecology And Ectoparasite Dynamics In A Tamaulipan Thornscrub Habitat, Brandi Giles

Theses and Dissertations

Small mammals play many roles in ecosystems and are known as great indicators of overall ecosystem function and health, but they are also highly competent hosts for ticks and tick-borne disease. In this study, I gathered data on small mammal community ecology and species diversity, abundance, and overall ectoparasite (i.e., ticks) dynamics in a south Texas Tamaulipan thornscrub habitat. I also assessed differences in these parameters in edge versus interior habitats across a gradient of habitat fragmentation and species assemblage. Lastly, I assessed which host and environmental factors can be utilized for predicting parasitization of small mammals in this habitat. …

Fabrication Of Advanced Materials For Chromatography, Sample Preparation, And Separations, And Accompanying Material Characterization, Dhananjay I. Patel

Theses and Dissertations

My dissertation primarily focuses on the fabrication of materials for solid phase microextraction (SPME) and separation devices. In my first project, I used direct current magnetron sputtering (DCMS) to prepare sputtered silicon coatings on fused silica fibers. These fibers were then subjected to the chemical vapor deposition of 6-phenyhexylsilane (6-PH) as a stationary phase. Six different types of fibers were made using two different throw distances (4 cm and 20 cm) and three different silicon thicknesses (0.5, 1.8, and 2.8 µm). These coatings were characterized by time-of-flight secondary ion mass spectrometry (ToF-SIMS), X-ray photoelectron spectroscopy (XPS), scanning electron microscopy (SEM), …

From The Corner Of One's Soul: The Methods Of Negotiating Tension In Cormac Mccarthy's Blood Meridian Or The Evening Redness In The West, Julian Pena

Theses and Dissertations

This thesis provides a practical and meaningful reading of Cormac McCarthy’s Blood Meridian or the Evening Redness in the West, one that is rooted in the claim that both Judge Holden and the Kid reflect two different methods for negotiating a tension impinged upon them by their external circumstances. Using a theoretical framework that is inspired by the social psychological Theory of Cognitive Dissonance, this thesis provides an extensive analysis of the novel’s fictional universe, Judge Holden, and the Kid. Such an analysis elucidates the violent nature of Blood Meridian’s universe and further reveals the character of Judge Holden …

Blue Lives Matter: Public Perception In Texas, Nohely Karyme Lozano

Theses and Dissertations

In recent years, Blue Lives Matter, a pro-policing movement, was established across the United States. The movement sheds light on the attacks and killings of police officers while on the line of duty. Also, it raises awareness of the dangers and risks law enforcement agents face while on duty and off duty. Throughout the years, the movement has gained many supporters across the nation. However, it has been controversial, and many considered it as a countermovement to Black Lives Matter. To bridge the gap in the literature, the researcher investigated the perception of Texans towards the movement. Moreover, the research …

Characterization Of Biomarkers For Alzheimer’S Disease And Hiv-1 Associated Neurocognitive Disorders, Armando Garces Iii

Theses and Dissertations

Alzheimer’s disease is a neurodegenerative disorder that is characterized by progressive cognitive decline and the accumulation of amyloid beta and neurofibrillary tangles in regions of the brain. These protein deposits are known to generate multiple effects on the brain that lead to neurodegeneration. It has been established that (Human Immunodeficiency Virus) HIV-1 accelerates the aging process of people living with HIV-1. Moreover, there is significant clinical evidence indicating a potential link between the neurodegeneration developed by those with an HIV-1 infection and AD. HIV-1 viral infection causes cognitive impairment known as …

Snook (Centropomus Undecimalis) Behavior And Accelerometer Telemetry In The Bahia Grande Of Texas, Jonathan Truett Cawlfield

Theses and Dissertations

There has been very little study of the Texas population of snook. No studies have have looked at behavior in the Texas snook population. In this study we look at behavioral patterns and activity level in Lower Laguna Madre snook utilizing accelerometer telemetry tags. Twenty-one common snook were surgically implanted with tags and monitored from summer and fall of 2019 until September 2020. The accelerometer tags which sum acceleration over the x, y, and z planes calculated (ODBA) which was used to estimate behavior. This behavior was then compared with environmental data like diel period, tidal period, water temperature, and …

Conceptual Insight Into The Application Of Innovative Educational Methods In Astronomy, Wahltyn A. Rattray

Theses and Dissertations

University students taking introductory astronomy courses were studied with a control group enrolled in a class with standard curriculum and an experimental group enrolled in a class with a curriculum using innovative instructional methods. Using multiple assessments, I analyzed the students’ astronomy knowledge and overall class experience to determine which curriculum was more instructionally effective. The innovative methods were developed with the ADDIE method and were based on the Karplus learning cycle which provided the framework for the astronomy curriculum. The end goal of the innovative curriculum is to produce graduates with better conceptual understanding of astronomy than with the …

Exploring The Role Of Stigmatic Exudate In The Water Lily (Nymphaceae) Pollination Mechanism Using N. Ampla (Salisb. Dc.), Luis Uribe

Theses and Dissertations

Water lilies are the only known plant group that uses hyperactive nectar glands to divest pollinators of their pollen. The nectar in Nymphaea ampla is thought to contain secondary metabolites that increase pollen deposition possibly by modifying pollinator behavior. This was explored utilizing visitation and fecundity data from the field coupled with survival and behavioral experiments in the laboratory. Replacing nectar with water reduced seed set in N. ampla which was attributed to reduced visitation in water-bearing flowers and not to effects on pollinator detention time. Exposure to nectar did not reduce survivability in Apis mellifera. Pollen and nectar foragers …

Bullet-Proof Boll Weevil: The History Of Boll Weevil Eradication, Evan A. Berg

Theses and Dissertations

Farmers and entomologists have all experimented with various methods to find the best way to defeat the United States' boll weevil. The techniques themselves, while expansive, can be examined within the scope of the years that they were used. This provides an exciting insight into how cotton pest management became more complex as the decades moved on and revealed how the science of cotton pest management evolved to deal with the boll weevil and other future cotton threats.

Evolutionary Development Study Of Firebrat (Thermobia Domestica), Luis Cantu Jr.

Theses and Dissertations

As most evolutionary development studies regarding wing origin take place using insects taxonomically closer to model organism, Drosophila melanogaster, there is a need of expanding studies to lower clades. While D. melanogaster is higher phylogenetically, basal clades would allow for a historical perspective of what occurs within the gene flow of conservative biomarkers. Further understanding of wings and flight would allow for a clearer understanding of how the migration of insects from sea to land has allowed them to become one of the most speciose taxa. Through the study of Thermobia Domestica, part of the Zygentoma, we expand on comprehension …

Characterization Of Soil Nematode Community As Influenced By Weedy Plants And Edaphic Properties, Orlando Garcia

Theses and Dissertations

Nematodes are one of the most critical species globally as they are part of most nutrient recycling. While nematodes play a vital role in nutrient cycling, little is known about them from an ecological standpoint. The majority of current research has focused on a singular component of the community, being those of herbivore/plant-parasitic nematodes. In this study, the community shifts of the nematode trophic groups were analyzed as influenced by native and invasive grasses species in the Lower Rio Grande Valley (LRGV) with the addition of edaphic soil properties.

In our study, the results indicate changes in the composition of …

A Gis-Based Model To Assess On-Site Sewage Facility (Ossf) Contamination Risk To Local Water Resources, Alvaro Garcia

Theses and Dissertations

In a collaborative effort between Texas Water Resources Institute (TWRI), Cameron County Public Health (CCPH), Texas A&M AgriLife Extension (TAMAE), and the University of Texas Rio Grande Valley (UTRGV), a GIS database that includes relevant OSSF information, such as location, system age, lot size, and other important parameters was created.

This OSSF database, along with publicly available GIS data, was used to create an integrative GIS-based risk assessment model where OSSF risk parameters were assigned a risk factor and combined into a spatial contamination risk for surrounding areas and their receiving waterbodies. Parameters were broken down into two categories: environmental …

Early Embryology In Collembola With An Emphasis On Wing Development, Samantha A. Gonzalez

Theses and Dissertations

The primary objective of this study was to further the understanding of the wing origin in insects. Currently there are several theories which are popular such as the tergum theory, the pleural plate theory, and the dual theory of wing origin. Studies for these theories have been done on crustaceans, the ancestors to modern day insects. By utilizing a pre insect hexapod, it may be possible to better understand the transition to insect wings. Members of the Collembola species Hypogastrurid are one of these pre-insect hexapods which may provide a clue into origins of wing development. During this study, the …

Synthesis And Characterization Of Centrifugally Spun Molybdenum-Based Nanomaterials For Lithium-Ion Batteries, Ramiro Gonzalez Jr.

Theses and Dissertations

The work presented in this thesis focuses on the processing and development of transition metal compound composite fibers as anode materials for rechargeable lithium-ion batteries (LIBs). Among the transition metal compounds, molybdenum compounds have risen as promising candidates of advanced electrode materials, in view of their natural abundance, virtuous mechanical/thermal stability, rich chemistry, high theoretical specific capacity, and multiple oxidation states of Mo. The current work reports synthesize MoO2/C and MoO3/C composite fibers drawn from centrifugal spun ammonium molybdate/PAN precursor fibers, followed by a thermal treatment stabilizing in air and calcination under argon atmosphere. The weight ratios of (MoOx, 2 …

Characteristics Analysis Of Electrochemical Impedance Spectroscopy (Eis) For Different Electrode Patterns, Shanzida Kabir

Theses and Dissertations

Electrochemical impedance spectroscopy (EIS) is a rapidly developing technique used in characterizing materials and interfaces. Using equivalent circuits as models can determine the electrical properties of heterogeneous systems like membranes or electrolytes. Different electrochemical processes like the electron transfer rate of a specific reaction or the capacitive behavior of the system, or even the diffusion-limited response can coincide. EIS is applicable to determine different electrochemical processes that can happen simultaneously. The purpose of this research is to find the optimal operating range for other AC electrokinetic mechanisms. Analysis of EIS can be helpful in both fundamental examinations of electrokinetic transport …

Understanding Teacher Perceptions And Experiences About Active Learning Techniques In High School U.S. History Courses At A Lower Rio Grande Valley School District, Juan J. Mendoza

Theses and Dissertations

This qualitative study explored the perceptions and experiences of teachers about the use of active learning techniques in high school United States history courses at a lower Rio Grande Valley school district. The study employed a phenomenology design for rich textural descriptions and a systematic exploration of the phenomenon of active learning techniques. Data were collected from individual semi-structured interviews and a focus group of 8 U.S. history teachers. Teacher lesson plans were examined to further corroborate evidence coded from the semi-structured interviews and focus group.

The research evidence suggested that active learning pedagogies create a progressive learning environment, they …

Prospecting For And Isolation Of Microalgae In South Texas, Mauricio Alejandro Peña

Theses and Dissertations

Microalgae is a very important microorganism that can be used for beneficial purposes for humans. One way to show the importance of algae in this planet is the contribution of Oxygen it provides to the atmosphere, which many organisms rely on (Medeiros et al., 2015). Carbon footprint has been one of the greatest causes for global warming and it is due to the use of fossils to create diesel. One of the ways to avoid contamination is to replace those fuels that are used on daily basis, such as for transportation. The microalgae are able to produce lipids that can …

Electrospun Pcl And Pcl/Gel Microfiber Scaffolds As Prototypes For Anterior Cruciate Ligament (Acl) Regeneration And Repair, Diego Rivera

Theses and Dissertations

Polycaprolactone (PCL) is a polymer that has been a focus of tissue engineering due to its range of applicability for biomedical applications. Synthesis of PCL from a microwave-assisted and stannous octoate-catalyzed ring-opening reaction with ε-caprolactone was accomplished. Aligned-fiber microfiber mats were generated via electrospinning for characterization. PCL microfiber mats were characterized via FTIR and scanning electron microscopy. These PCL microfiber mats were mechanically tested to examine their applicability as tools for knee ligament repair. During tensile testing, non-fiber aligned mats lacked the sufficient elastic modulus. Fiber-aligned PCL samples both and gelatin-coated were tested and showed enhanced elastic modulus and extension …

Duet Phonology And Syntax Of The Red-Crowned Parrots In South Texas, Abigail Pozulp

Theses and Dissertations

Bird behavioral interaction systems show a preference for temporal precision. This preference is exemplified in the way many species avoid masking of vocal signals. Antiphonal duetting in songbirds suggest that overlapping notes are a sign of poor temporal coordination which can signify a weak pairbond, a possible cue for conspecifics seeking to usurp territories or mates. However, parrots (Psittacidae) are accomplished yet understudied duetters in nature. I recorded antiphonal duets produced by a wild population of red-crowned parrots (Amazona viridigenalis) in Brownsville, Texas. Temporal and acoustic variation of signals was assessed within and across a sample of mated …

Development Of A Novel Strategy To Improve Checkpoint Immune Response In Pancreatic Cancer, Poornima Devi Shaji

Theses and Dissertations

Pancreatic Cancer is the 3rd lethal causing cancers in United States with a survival rate less than 5-7%. In advanced unresectable pancreatic cancer, treatment options are restrained to surgery because of its extreme aggressiveness. Immunotherapy, one of the current advanced treatments has shown promising response in other cancers. However, this therapy is limited in pancreatic cancer due to desmoplasia and fibrotic tumor microenvironment (TME).

Our superparamagnetic iron oxide nanoparticles (SPIONS) of curcumin (Curcuma longa, principal curcuminoid of turmeric) have potential ability to inhibit desmoplasia and tumor stroma with an increased bioavailability. This would soften up the tumors for …