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Arthropod Diets In Chihuahuan Desert Snakes, Victor Manuel Parga

Open Access Theses & Dissertations

Over the past century, studies in herpetology regarding snake diets have been commonly focused on those species that feed or specialize in vertebrate prey items. For those that feed primarily on invertebrates however, little work has been done in determining diet specializations and comparing diets within a community of species. This Thesis focuses on small species of snakes that feed primarily on arthropods in a Chihuahuan Desert community, and will investigate if these are diet generalists or specialists. To this end, stomach contents were examined from preserved specimens of the following species: Rena humilis and Rena dissecta (Leptotyphlopidae), Gyalopion canum …

The Protective Effects Of Ferrostatin-1 (Fer-1) In Response To Excitotoxicity In Mouse Hippocampal Slices, Mireya Nael Ramirez

Open Access Theses & Dissertations

The development of different neurological disorders has been associated with the accumulation of reactive oxygen species (ROS). Elevated ROS levels can disrupt the neuronal electrical activity. This phenomenon has been seen during epilepsy and neurodegenerative diseases like Parkinson's disease. Furthermore, the excess of ROS and development of such disorders have been linked to neuronal cell death partly due to excessive, non-physiological glutamate release. Ferroptosis is a recently defined iron-dependent cell death mechanism. Inducible by a small molecule called erastin, ferroptosis was first described in cancer cells. Erastin-induced ferroptosis differs from apoptosis, necrosis and autophagy, since it leads to different biochemical …

A Test Of Criteria For Determining "Optimal" Ppor Model Reference Groups: Measuring Excess Infant Deaths In The Border Region, Alexis Nicole Ramos

Open Access Theses & Dissertations

Background: Infant mortality is one of the strongest indicators of social and economic development in all countries. Understanding infant mortality is critical for understanding the health of nations. Strategies for lowering infant death rates are needed. The Perinatal Periods of Risk Model (PPOR) is an approach that allows communities to determine when infant death and excess death is occurring by categorizing death into four perinatal categories. Excess infant deaths are determined by defining a reference group with the lowest mortality rate, and then comparing the reference group rate to other subgroups. The typical reference group has been defined as white, …

Tribological Characterization Of Ti-Based Alloys For Biomedical Applications In Simulated Body Fluid, Edgar Reyes

Open Access Theses & Dissertations

Tribology is a terminology introduced in the 1960's and it is a study that relates to the investigation of the damage of materials. Titanium, as a material used for a wide range of application, it has been brought to the attention of researchers some characteristics such as its much lower density if compared to steel, its capability as an alloying agent with an amount of metals to enhance physical and mechanical properties, to name just a few characteristics. This paper will discuss the performance on tribology behavior in two different Titanium alloys. These Titanium alloys are Ti-6Al-4V (Ti64), and Ti-24Nb-4Zr-8Sn …

Integrated Immunoassays On Paper/Polymer Hybrid Microfluidic Devices For Low-Cost Detection Of Disease Biomarkers, Sanjay Sharma Timilsina

Open Access Theses & Dissertations

Infectious diseases and cancers have been the major cause of global death and disability causing a significant impact on global health and economies. Enzyme-linked immunosorbent assay (ELISA) is one of the most widely used laboratory diagnostic methods for infectious diseases and cancer. ELISA detects proteins based on their binding to immobilized antibodies or antigen. Even though most ELISAs performed today in 96-well plates are well suited for high throughput assays, performing ELISA in low-resource settings is limited by several factors, such as long incubation time, large volumes of precious reagents, and well-equipped laboratories. Herein, we have developed multiple simple, miniaturized …

Novel Therapeutic Approaches For Trypanosoma Cruzi Infection, Caresse Lynn Torres

Open Access Theses & Dissertations

Trypanosoma cruzi (T. cruzi) is the causative agent of Chagas disease (ChD), an emerging illness prevalent in South and Central America. Presently, benznidazole and nifurtimox are the only two clinically available drugs against T. cruzi, which have high toxicity and limited efficacy in the chronic phase of the disease. This ailment affects 8-10 million people and has become an emerging concern in the U.S leading to an urgent need for the discovery of new treatments. Despite all efforts, there is no human vaccine available. Therapeutic vaccines are a possible option for chronic ChD in which the vaccine is used after …

Walls And Wilderness: Analyzing The Impacts Of Border Barriers On U.S. Government Lands Of The United States - Mexico Border, Bryce Garrett Fugate

Open Access Theses & Dissertations

This paper seeks to describe the impacts of physical structures (fences, walls, barricades, etc.) on five selected areas of federally-protected U.S. lands along the U.S.-Mexico border that fall under the jurisdiction of the U.S. Department of the Interior. The five selected areas are: Santa Ana National Wildlife Refuge, Big Bend National Park, Organ Mountains - Desert Peaks National Monument, the Tohono O'odham Nation Reservation, and Organ Pipe Cactus National Monument. The research looks into the historical development of structures put in place on the U.S. - Mexico border, how they have become ever more ubiquitous in the region, and what …

Impact Of Patient Demographics And Health Insurance On Hospital Discharge, Ana Acosta

Open Access Theses & Dissertations

Based on discharge data collected with 241 patients who received medical care from a fall injury between 2014 and 2015 at the emergency room in a general hospital in El Paso, Texas, I will examine whether individuals over age 55 have health insurance and the type of care that is recommended to patients after being discharged. In particular, I will examine demographics, including ethnicity, age, and language on whether the patient paid with insurance and the disposition of discharge from the emergency department after a fall. Additionally, I will examine which demographic factors are associated with disposition of discharge- facility, …

Computational Modeling Of Ring Dna-Carbon Nanotube Sensors, Aliasghar Alizadehmojarad

Open Access Theses & Dissertations

Non-covalent interactions between single-stranded DNA (ssDNA) oligonucleotides and carbon nanotubes have provided a unique class of tunable chemistries for applications in nanotube chirality purification, gene delivery, electrochemistry, and nanosensor development. However, mechanistic insight into both the photophysical and intermolecular phenomena underlying their utility in such applications is lacking, resulting in non-systematic approaches to producing DNAnanotube based technologies. In this work, we explore the molecular interactions between ssDNA polymers, in particular (GT)6, and single-walled carbon nanotubes (SWNT) in an ultrasensitive nanosensor for a modulatory neurotransmitters dopamine. Classical molecular dynamics simulations show that (GT)6 oligonucleotides adopt ordered, ring-like conformations around SWNT in …

Effects Of Increasing Deciduous Shrub Litter On Ecosystem Functioning In Alpine Tundra, Alejandro Emmanuel Benhumea

Open Access Theses & Dissertations

Rising temperatures due to global warming have resulted in rapid environmental changes in northern environments, resulting in an increase in deciduous shrub growth which has the potential to alter soil ecosystem properties and processes. In order to address some potential mechanisms by which shrubs alter ecosystem properties and processes, we designed an experiment which separated the effects of physical shrub presence and the effects of litter quantity in a fully factorial experiment on a north facing alpine plateau in the southwest Yukon, Canada. Specifically, we asked the following questions: What are effects of shrub litter, independent of shrub presence, on …

Improving Instructional Leadership: A Multi-Case Study Of Principal Perspectives On Formal Evaluations, Brenda Chacon-Robles

Open Access Theses & Dissertations

In a time when public schools continue to be scrutinized, school leadership never mattered more in order to exercise school reform. This qualitative study examined how five principals working in an urban school district perceived their evaluation and how it contributed to their practice. I applied a descriptive case study approach. Evaluations can be intended to find "the best way" to do things overall, to discover a better way to do things in a particular situation, or to develop practitioners' abilities to respond and adapt in different ways (Shaw, 2006). The instructional leadership piece provides insight to what it takes …

Trace Metal And Metalloid Behavior In The Submicron Scale Components Of Coal Fly Ashes: Insights From Combined Microscopic And Microbiological Studies, Matthew Costa

Open Access Theses & Dissertations

For over a century, coal has been used worldwide to meet ever-growing energy demands. Coal combustion accounts for over 30% of electricity generation in the United States. In the U.S., coal combustion produces annually over 100 million tons of coal combustion products (CCPs) of which only 30% are used in beneficial and economic ways. One of the primary CCPs from coal-burning power plants is fly ash, typically fine-sized and enriched in many trace elements (e.g., arsenic, chromium, lead, and vanadium). When disposed in the environment, fly ash may release significant concentrations of trace elements into surrounding ecosystems and induce toxicity …

Nutrition Label Accuracy And The Theory Of Triadic Influence: The Impact Of Knowledge On Healthy Food Choices In A Predominantly Hispanic Sample, Mosi Staudt Dane'el

Open Access Theses & Dissertations

Unhealthy food choices and the outcomes of those choices are a significant concern in the United States. Multiple governmental agencies recommend using nutrition labels to promote healthier food choices. This study investigated this claim using the theory of triadic influence to examine the efficacious use of nutrition labels on food choices. The theory of triadic influence presents a model of variables that affect food choice, including knowledge pathways on which this study focuses. Within the model, we expected increased scores on two measures of health knowledge to predict nutrition label understanding, which predict healthy food attitudes. Next, we expected that …

The Hierarchical Structure Of Nanoporous Carbon Electrode Materials Elucidated By Water Sorption: A Comparison Of Multiple Structural Models, Jose Ali Espitia

Open Access Theses & Dissertations

The total amount of energy that an electrical double layer capacitor (EDLC) can store depends on the voltage and the accessible surface area for ion electrosorption. Nanoporous carbon materials with a high specific surface area, such as carbide derived carbon (CDC), make ideal electrodes for EDLC devices. CDC materials have fine-tuned pore sizes in the subnanometer range which are controlled by the initial carbide (TiC) and annealing conditions. Water can enter TiC-CDC pores and give filling fractions in excess of 0.6 g/g (H2O/C). Recent reports of water's diffusional dynamics dependence on CDC pore size indicate confinement effects similar to that …

Hierarchical Multiplicity Control Methods For Linear Models, Dimuthu Dilshan Fernando

Open Access Theses & Dissertations

HypoThesis testing is a commonly used statistical inference technique on which a statement of the population is investigated through the evidence from a representative sample of the population. With simultaneous testing of more than one null hypotheses need for an appropriate multiple comparison method is essential. With motivation from the study of Bogomolov et al. (2017) we have modified a multiple comparison tree structure to build the required comparisons and focus on controlling the FWER (Family Wise Error Rate) using the Bonferroni procedure. The proposed method has advantages such as controlling the global error rates separately at each level, families …

Backward Elimination Algorithm For High Dimensional Variable Screening, Sophia Korkor Foli

Open Access Theses & Dissertations

In recent times, variable selection in high-dimensional data has become a challenging prob- lem. We investigate here a popular but classical variable screening method, the Back- ward Elimination (BE) in a high dimensional setup (small-n-large P). The BE method as a variable screening method reduces the dimension of small-n-large P data into a lower dimensional data and then established shrinkage methods such as: LASSO, SCAD and MCP can be applied directly. To overcome the problems in high dimensional data, Chen and Chen (2008) recently developed a family of Extended Bayesian Information Criterion (EBIC) which is consistent with finite sample properties …

Environmental And Genetic Factors Affecting Antibiotic Resistance Of Extended Spectrum Î?-Lactamase Bacteria From The Rio Grande River In El Paso, Tx And Cd. Juarez, Mexico, Maria D. Fuentes

Open Access Theses & Dissertations

Background: The Rio Grande River provides a major source of potable and agricultural water for the population of the Texas/Mexico border region. Cattle farming and ranching are the most prevalent activities, which may contribute to the microbial burden of pharmaceuticals into our state's water resources. Antibiotics, presumably released into the environment by discharges originating from waste-water treatment plants, septic disposal systems, animal feeding operations and urban runoff have a definite impact on the ecosystem and may contribute to an increase in antibiotic resistance. We hypothesized that waters of the Rio Grande River contained Multi Drug Resistant Organisms (MDRO) and mobile …

A New Approach To Multiplanar, Real-Time Simulation Of Physiological Knee Loads And Synthetic Knee Components Augmented By Local Composition Control In Fused Filament Fabrication, Joshua Taylor Green

Open Access Theses & Dissertations

Despite numerous advances in biomedical engineering, few developments in surgical simulation have been made outside of computational models. Cadavers remain the primary media on which surgical research and simulation is conducted. Most attempts to quantify the effects of orthopedic surgical methods fail to achieve statistical significance due to limited quantities of cadaver specimen, large variations among the cadaver population, and a lack of repeatability among measurement techniques. The general purpose of the research covered in this dissertation is to develop repeatable simulation of physiological loads and develop techniques to fabricate a synthetic-based replacement of cadaver specimens. Future work applying this …

Structural And Optical Investigations Of Rbxcs1-Xh2po4, Alex D. Price

Open Access Theses & Dissertations

Proton conductor solid acid electrolytes RbxCs1-xH2PO4 (0≤x≤1) have been investigated using second harmonic generation and powder x-ray diffraction. Second harmonic generation is an optical technique which can be used to study the structural properties of materials. Microscopes of this nature have the ability to image objects with a variable penetration depth in a non-destructive manner, allowing for great potential to be used for in situ observations of the electrolyte’s structure when in a fuel cell under operating conditions.

X-ray powder diffraction was carried out on the series of samples and found for values of 0≤x≤0.5 the structure of the material …

The Structural And Functional Study Of The Human Mitochondrial Hsp60 Chaperonin In Neurodegenerative Diseases, Jinliang Wang

Open Access Theses & Dissertations

Proteins are essential elements that are responsible for a variety of cellular activities within organisms, including catalyzing metabolic reactions, DNA replication, responding to stimuli, providing structure to cells and organisms, and transporting molecules. After protein synthesis in the ribosome, the unfolded protein need to fold into their unique compact structures so that they can perform their full biological functions. The biologically active structure of a protein is referred to the native-state of the protein with biological activity. The process of protein folding is one of the most important and challenging research topics of contemporary biochemistry, especially for its central role …

Technical Project Management: Union Of Systems Engineering Processes With Project Management Processes, Deyaaldeen M. Abusal

Open Access Theses & Dissertations

Today, most projects in technical fields utilize project management to complete projects as planned, and some of the projects utilize system engineering to cover the project in both technically and commercially. This Thesis investigates the relationship between Project Management (PM) and Systems Engineering (SE) to determine if a suitably professional level of management and level of quality can be achieved. When studying PM and SE separately and make a comparison between both, there is much overlap between these two mature fields. The project could be planned and completed solely by either process. This study combines both fields of Project Management …

Insights Into The Interaction Of Copper Oxide Nanopar-Ticles With Sweetpotato (Ipomoea Batatas (L.) Lam.): The Role Of Lignin On Copper Uptake And Translocation, Nestor Javier Bonilla Bird

Open Access Theses & Dissertations

Sweetpotato [Ipomoea batatas (L.) Lam.] is widely cultivated in many countries worldwide. The world production of sweetpotato is around 127 billion tons and it is ranked seventh in the world as a staple food. After harvesting, sweetpotato storage roots are treated with fungicides to prolong shelf life. Lignin plays an important role in the conservation of the storage roots. One of the practices to activate the lignification pathway is called “curing process.” The roots are placed under 80% relative humidity at a temperature of 29 ºC for a period of 7 to 15 days, followed by a cooling period at …

Insulin Modulates The Strong Reinforcing Effects Of Nicotine And Changes In Insulin Biomarkers In A Rodent Model Of Diabetes, Bryan Cruz

Open Access Theses & Dissertations

This study examined whether the strong reinforcing effects of nicotine and changes in insulin biomarkers observed in diabetic rats are modulated via insulin. A model of diabetes was employed involving administration of streptozotocin (STZ), which produces hypoinsulinemia in rats. The present study included vehicle- or STZ-treated rats that received sham surgery or an insulin pellet. Two-weeks later, the rats were given extended access to intravenous self-administration (IVSA) of saline or nicotine. Concomitant changes in food intake, water responses, and body weight were assessed during 12 days of IVSA. After the last session, plasma levels of insulin, leptin, amylin, and glucagon-like …

Comparison Of Stride Length And Stride Frequency Patterns Of Sprint Performance In Overground Vs Motorized Treadmill Sprinting., Fayon Kamieka Gonzales

Open Access Theses & Dissertations

The purpose of this study was to investigate the relationship between different kinematic parameters when maximal effort sprints are performed overground and on a motorized treadmill by recreationally trained and collegiate level sprinters. To accomplish the goals of this study, we measured stride length, stride frequency, contact time, and flight time overground and on a motorized treadmill to determine what differences or similarities can be identified. Anthropometric measurements such as the height, body weight, lower limb length, and lower limb circumference were also recorded. Subjects' performance of a 60 meter sprint (50 meter acceleration, 10 meter maximal velocity) was measured …

Detection Of Pharmaceuticals And Personal Care Products In The Rio Grande And Their Effects On A Model Aquatic Invertebrate (Rotifera, Monogononta: Plationus Patulus), Enrique David Garcia

Open Access Theses & Dissertations

Rivers, including the Rio Grande, receive discharges from urban, agricultural, and industrial areas. These discharges have potentially harmful contaminants that may affect life span, fecundity, and/or behaviors of aquatic organisms. In this project, water quality was analyzed near a discharge point source and impacts of pharmaceuticals and personal care products (PPCPs) on a non-target organism (Plationus patulus) were investigated. Long-term and integrative organic samplers (POCIS) were left in situ for about 1 month near a wastewater treatment plant that discharges effluent into the Rio Grande. Over 40 PPCPs, including carbamazepine (ranging from 17.50 to 584.29 ng/L), erythromycin (ranging from 0.51 …

Onshore-Offshore Velocity Models North Of The Mendocino Triple Junction In Northern California, Alan Jacquez

Open Access Theses & Dissertations

The Mendocino Triple Junction (MTJ) marks the boundary where the Gorda plate, North American Plate, and Pacific Plate meet, separating the Cascadia subduction zone to the North from transform tectonics of the San Andreas plate boundary. This actively deforming region experiences high seismic activity and young geological features. Here we examine offshore and onshore seismic wide-angle reflection and refraction data north of the MTJ crossing the Cascadia subduction zone from offshore northern California to the Western edge of the Sierra Nevada. We image subsurface structures in this region by creating P-wave velocity models using datasets collected in 1993 to 1994 …

Age At First Offense As A Predictor Of Recidivism Among High-Risk Juvenile Delinquents Versus All Juvenile Delinquents, Claudia Iliana Lopez

Open Access Theses & Dissertations

Researchers have generally found a moderate negative correlation between juvenile delinquents' age at first offense and their risk of recidivism (Cottle, Lee, & Heilbrun, 2001). However, two studies at the El Paso Juvenile Probation Department (El Paso JPD) by Valenzuela (2011) and Ranadive (2014) found the correlation of age at first referral with recidivism to be non-significant and close to zero. A possible explanation for these findings at El Paso JPD is that age at first referral is predictive of recidivism among high-risk juvenile offenders but not in the general population of all juveniles referred to the justice system. The …

Formative Evaluation Of The Health Belief Model As A Valid Theoretical Framework For "The Diabetes Garage", Renee Alexandria Orrantia

Open Access Theses & Dissertations

Background & Significance. Recent studies estimate the prevalence of diabetes among Hispanics/Latinos (H/L) to be 16.9% and 18.7% among H/L men specifically. To address this disparity, the Diabetes Garage (DG), a culturally tailored Diabetes Self-Management Education and Support (DSME/S) program, was designed to engage H/L men in diabetes self-management. Because seriousness of diabetes best predicts men’s engagement in self-care, the Health Belief Model (HBM) was chosen as the central theoretical framework. The HBM hypothesizes that the cue to action (i.e. DG) increases men’s perceived diabetes risk/severity/threat, self-efficacy in self-care, and health outcomes. Aims & Objectives. This research was aimed to …

Evolving Identity: A Case Study Of Mentor Science Teachers, Melissa N. Ortega

Open Access Theses & Dissertations

This dissertation is a case study of how mentor science teachers understood and presented their experiences, challenges they faced, and learning of being and becoming a mentor teacher while they participated in a year-long district mentoring program. The purpose of this study is to examine what science teachers learn in their experiences as mentors and the role this learning played on their identities as professional educators. According to Bullough (1997), teacher identity is of vital concern to teacher education as it is the “basis of meaning making and decision making” (p. 21). Existing research on science teacher identity indicate that …

Yeezy Taught Me: Race, Gender, Class & Identity Through Rap Music, April Marie Reza

Open Access Theses & Dissertations

This study will explore identity construction by examining the intersectionality of race, gender, and class within rap music, specifically the music of Kanye West. It will expand current research by exploring social themes within rap music and how they impact the construction of one's identity. The primary goal of the study is to analyze rap music and intersectionality within the lyrics, following how they interconnect to shape and influence a listeners identity. Furthermore, this study will analyze lyrics of a popular figure within the rap genre and the messages that are communicated through an artist's music career.

Key Words: rap …