Digital Commons Network^™

Sweet Potato In The Lower Rio Grande Valley: Evaluating Performance Across Several Cultivars, Jon Dale

Theses and Dissertations

In Texas’ subtropical, semiarid Lower Rio Grande Valley (LRGV), citrus and sugarcane cultures have dominated specialty crop production for more than a half-century. However, the future of these high-dollar crops is becoming uncertain with increases in exotic pathogens, intensifying urbanization and the overarching complexities of both climate change and binational governance of Rio Grande Basin waters. For these reasons, the region’s specialty crop sector needs to be ready for alternatives that could benefit both market outlets and reduced input dependencies. Sweet potato (Ipomoea batatas), commercially grown in various similar climates worldwide with limited water resources, could be one …

Self-Supervised Representation Learning For Motion Time Series: A Case Study In Activity Recognition, Luis Carlos Garza Perez

Theses and Dissertations

In this thesis we will learn about what contrastive learning and time series are and understand the differences between supervised and self-supervised frameworks in machine learning. In addition, we will describe how the newest and most efficient self-supervised learning framework for visual representations to this date works, called SimCLR, which was originally developed to obtain useful vector representations from static images. We will also explain what TS2Vec is, and how a combination of both approaches can be applied to the concept of a time series, and still be able to extract a vector representation of the subject described by the …

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 …

Irreverent Womanhood: The Healing Of Intergenerational And Cultural Trauma In The Chicanx And Latinx Sonic Poetry Of Amalia Ortiz And Melissa Lozada-Oliva, Yasmine A. Gomez

Theses and Dissertations

The connections between nontraditional forms of literature and spiritual activism lie within the resistive practices of Chicanx Feminism. This thesis argues that cultural healing and social change is dependent upon the recognition of trauma as a step towards enacting social justice. Additionally, this thesis focuses on the figure of Coyolxauhqui and indigenous motherhood to reveal procedures for change. Through the theory of trauma, this thesis examines the nontraditional Chicanx/Latinx poetry of Amalia Ortiz’s sonic rock opera, Cancíon, Cannibal, Cabaret, & Other Songs and Melissa Lozada-Oliva’s novel in verse, Dreaming of You.

My investigation into the breaking of gendered …

Graphene-Conductive Ink Coated Laser Engraved Kapton Electrochemical Biosensor For The Detection Of Dopamine And Immune Sensing, Dipannita Ghosh

Theses and Dissertations

Novel and flexible disposable laser-engraved Kapton (LEK) electrodes modified with graphene conductive inks have been developed for dopamine and Interleukin-6 (IL-6) detection. The LEK sensors exhibit high reproducibility (RSD=0.76%, N=5) and stability (RSD=4.39%, N=15)after multiple bendings, and thus make the sensors ideal for wearable and stretchable bioelectronics applications. We have developed graphene conductive ink- PEDOT:PSS (G-PEDOT:PSS) and polyaniline (G-PANI) based electrode coatings for working electrode modification to improve the sensitivity (41.41 times higher for screen printed electrode with G-PEDPT:PSS ink modification),and limit of detection (LOD) . We have further compared the performance of the fabricated electrodes with commercially available screen-printed …

Quality Of Life Among Caregivers Of Individuals With 22q11.2 Deletion Syndrome And Intellectual Disability, Sandra Garza Ochoa

Theses and Dissertations

Caregiving for a person with 22q11.2 chromosome deletion syndrome (22q) often entails dealing with medically life-threatening complications and is significantly compounded when the care recipient has comorbid 22q and intellectual disability (ID). The purpose of this study was to examine the effect of support, spirituality, and resiliency on the quality of life (QOL) of caregivers of individuals with comorbid 22q/ID to ascertain if these protective factors would reduce their caregiving burden. Study participants consisted of 469 caregivers of persons with 22q/ID who were recruited through 22q social advocacy groups. Correlational analyses, analyses of variance, and multiple regression analysis were used …

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 …

An Examination Of Factors Impacting Student Decisions To Engage In Physical Activity At A Hispanic-Serving Institution, Glenn R. Gray

Theses and Dissertations

College students at a large south Texas university have proven consistently that they have a higher-than-average Body Mass Index (BMI), spend less time per week engaged in physical activity, and in general feel that they are less healthy than students in a national cross-sectional survey of college students by the American College Health Association (ACHA, 2021). This project investigates the barriers to activity and the motivators to engage in activity. In this cross-sectional study, the Exercise Motivations Inventory-2 and the Barriers to Being Active instruments along with a demographic survey have identified motivators and barriers. The collection of basic demographic …

Attitudes And Compassion Of Student Counselors-In-Training Toward Individuals Who Are Homeless, Kristine R. Gonzalez

Theses and Dissertations

With the increased numbers of homeless individuals over the past several years, it is important to consider factors that contribute to chronic homelessness, including barriers to service delivery that impede one’s ability to exit homelessness. The purpose of this quantitative study was to examine the attitudes and compassion among student counselors-in-training (SCITs) toward individuals experiencing homelessness as these students represent future mental health providers who will be serving the homeless, a highly marginalized population. A total of 162 graduate students from two southwestern Hispanic-serving institutions were recruited for the study. A correlational analysis, independent t-tests, and one-way ANOVAs were conducted …

Developing Executable Digital Models With Model-Based Systems Engineering – An Unmanned Aerial Vehicle Surveillance Scenario Example, Viviana Guadalupe Lopez

Theses and Dissertations

There is an increase in complexity in modern systems that causes inconsistencies in the iterative exchange loops of the system design process and in turn, demands greater quality of system organization and optimization techniques. A recent transition from document-centric systems engineering to Model-Based Systems Engineering (MBSE) is being documented in literature from various industries to address these issues. This study aims to investigate how MBSE can be used as a starting point in developing digital twins (DT). Specifically, the adoption of MBSE for realizing DT has been investigated, resulting in various literature reviews that indicate the most prevalent methodologies and …

Data Science For Hospital Antibiotic Stewardship, Saikou Jawla

Theses and Dissertations

Antibiotics are widely used to treat bacterial infections, but their misuse leads to antibiotic resistance. Antibiotic resistance is one of the biggest threats to global health, food security, and development today. Antibiotic resistance leads to higher medical costs, prolonged hospital stays, and increased mortality. Antimicrobial stewardship is an approach to measure and improve the appropriate use of antibiotics in healthcare settings. Data science has the potential to support these programs by providing insights into antibiotic prescribing patterns, identifying areas for improvement, and predicting patient outcomes. We explored the role of data science in hospital antibiotic stewardship programs, including statistical methods …

Monitoring Of Ac Motors Parameters Using Industrial Internet Of Things, Mohammad Muheisen

Theses and Dissertations

In this thesis, the industrial internet of things has been introduced, as a very newborn research field. The suggested prototype has been assembled at the university laboratory to simulate the system conditions. Two three-phase induction motors have been utilized to perform this study, to monitor and gather data, regarding vibration and temperature. As a very newborn field, the data collected from the two motors can be analyzed to achieve a couple of goals, in energy consumption, to reduce the financial burden of the remedy works. A fast Fourier transformer has been applied to measure the motor's vibrations, and the current …

Flow Monitoring And Tidal Exchange Ratio Estimation For The Bahia Grande After Widening Of The Carl Joe Gayman Pilot Channel: Bahia Grande, Cameron County, Tx, Sabas Lopez Iii

Theses and Dissertations

The Bahia Grande (BG) is an 8,500-acre set of coastal bays and wetlands located between Brownsville and Port Isabel, Tx, near the Gulf of Mexico (GOM) coastline. In 2005, the Carl Joe Gayman Pilot Channel was constructed to address hypersalinity concerns that resulted from natural and anthropogenically-caused tidal isolation since the early 1940’s. In 2022, the Texas General Land Office (GLO) increased the channel’s width and depth in anticipation of increasing tidal exchange ratios by a factor of two to three. Once the channel widening was complete, two SL-1500-3G side-looking acoustic doppler current profilers (ADCPs) were periodically deployed beneath the …

Effects Of Missing Data Imputation Methods On Univariate Time Series Forecasting With Arima And Lstm, Nicholas Niako

Theses and Dissertations

Missing data are common in real-life studies and missing observations within the univariate time series cause analytical problems in the flow of the analysis. Imputation of missing values is an inevitable step in the analysis of every incomplete univariate time series data. The reviewed literature has shown that the focus of existing studies is on comparing the distribution of imputed data. There is a gap of knowledge on how different imputation methods for univariate time series data affect the fit and prediction performance of time series models. In this work, we evaluated the predictive performance of autoregressive integrated moving average …

Long-Term Spatial And Temporal Assessment Of Criteria Air Pollutants Concentration Trends In The Lower Rio Grande Valley Region Of Texas, Usa, Md Salahuddin Majumder

Theses and Dissertations

Air pollution is a substantial environmental challenge all over the world. This study investigated the long-term air pollution levels in the Lower Rio Grande Valley region, by utilizing data collected from five continuous ambient monitoring stations in two counties over 23 years, from January 2000 to December 2022, to analyze daily, monthly, and seasonal variations of different pollutants, including ground-level ozone, particulate matter, and carbon monoxide. This study also identified distinct daily and seasonal patterns for O3, PM2.5, PM10, and CO at each monitoring site, influenced by factors such as traffic emissions, temperature, solar radiation, indoor heating, and weather conditions. …

Disaster Risk Perception, Climate Change Awareness, And Disaster Preparedness Among University Of Texas Rio Grande Valley Students, Anandita Roy

Theses and Dissertations

University students are usually young and have low-income resources, live in dormitories or low-rent housing near the university, and have little to no disaster experience. Therefore, they are vulnerable to disasters due to a lack of resources for preparation. To better understand the vulnerability of students to disasters, the study aims to assess the perceptions of disaster risk, climate change awareness, and the level of disaster preparedness of students at the University of Texas Rio Grande Valley (UTRGV). In this study, we collected data from 320 students who participated in an online survey. The study’s findings provide an understanding of …

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 …

No Middle Ground: Demagogic Rhetorical Practices At The Truth And Courage Bus Stop In Harlingen, Tx, Kymberly O. Morquecho

Theses and Dissertations

This thesis examines the rhetorical and discursive strategies embraced by conservative politicians and their supporters on the campaign trail. Using Dr. Patricia Roberts-Miller’s definition of demagogic cultures coupled with the five markers, or tendencies, of these cultures, I explore how the speakers at the October 22, 2022 Truth and Courage PAC campaign rally in Harlingen, TX deployed these tactics to galvanize voters to vote for TX-34 Republican candidate Mayra Flores. Through a combination of descriptive and rhetorical analysis, I demonstrate how these presenters engage in demagogic and anti-democratic rhetorical moves to an audience of Hispanics. Lastly, I outline how these …

A Machine Learning Approach To Obese-Inflammatory Phenotyping, Tania Mayleth Vargas

Theses and Dissertations

Obesity is the accumulation of an abnormal, or excessive, amount of fat in the body, which can have negative effects on overall health. This excess accumulation of macronutrients in adipose tissue can cause the release of inflammatory mediators, leading to a proinflammatory state. Inflammation is a known risk factor for various health conditions, including cardiovascular diseases, metabolic syndrome, and diabetes. This study sought to examine the use of data mining methods, particularly clustering algorithms, to identify inflammatory biomarker phenotypes and their association with obesity in a local adolescent population. The algorithms evaluated in this study included: k-means, Ward's hierarchical …

How Can Increased Parental Involvement Facilitate Greater Student Engagement And Academic Success Within One Rgv Middle School, Jaime H. Serna

Theses and Dissertations

The purpose of this study is to explore how can increased parental involvement be encouraged in the K-12 school in the Rio Grande Valley in order to facilitate greater student engagement and academic success. An action research project will be done to explore middle school teachers’ perspectives on parental involvement and the effect it has on student academics. Research will take place in Sunview Middle School were interviews, observations will be conducted to teachers, parental involvement assistant and administrator. Data will assist to improve and promote the parental involvement program to assist all stakeholders and better assist our students.

Geospatial Analysis Based On Hurricane Storm Surge Scenarios On Coastal South Texas And North Mexico, Layda Belia Spor Leal

Theses and Dissertations

The coastal area of the Lower Rio Grande Valley, Texas, and Northern Tamaulipas, Mexico, has historically faced a variety of natural disasters involving flooding hazards, such as hurricanes and tropical storms. These scenarios not only represent imminent danger for the population in the area but can lead to long term effects on the infrastructure located in the impact zone. As such, it is imperative to conduct analysis on not only the specific areas that will be affected, but the severity of flooding that can result after a catastrophic event. Modelling work that simulates the storm surge in case of various …

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 …

An Investigation Of Standardized Assessment Performance For Middle School Students Before And During The Covid-19 Pandemic, Michael Norman Voth

Theses and Dissertations

The purpose of this study is to examine how the COVID-19 pandemic has affected the learning of students in public education through the analysis of standardized assessment performance before and during COVID-19. The study also compares virtual learning and face-to-face students’ change in performance on the standardized assessments. To answer the research questions, the quantitative research uses 5th and 7th grade math and reading STAAR data from 2019 and 2021 for the same cohort of students at a suburban ISD in Texas. The casual-comparative research study suggests that there is a significant drop in students’ performance on standardized assessments in …

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 …

Self-Perceived Stigma Of Caregivers With Children On The Autism Spectrum In Latin America, Leah Michelle Jara

Theses and Dissertations

With the prevalence of Autism Spectrum Disorder (ASD) continuing to spread along with limited knowledge on the disorder’s service accessibility, many caregivers are required to care for lifelong obligations, often at the sake of their own mental, physiological, and emotional health. This study aimed to explore self-perceived stigmas of caregivers in Latin America based on predictors including demographics, severity, and type of healthcare coverage. Participants included 2483 caregivers in Latin America who completed a survey targeting the challenges, priorities, barriers to care, and stigma they face caring for an individual with autism. Findings showed that age had a weak inverse …

From “Cowardice” To “Shellshock”: The Definition And Treatment Of Mental Health In The United States Marine Corps During The Age Of The Great War, Itzel Marquez

Theses and Dissertations

The aim of my master’s thesis is to study how the United States’ Marine Corps recognized, defined, and treated mental health issues during the Great War and how this translated into the treatment of Marines by their peers and commanding officers. Similar to other countries that fought in the Great War, also referred to as World War I, the United States witnessed intense discussions about the psychological effects of war. The question of whether and how modern warfare affected troops’ mental health was addressed by all branches of the United States’ military. Yet, the issue of mental health in the …

Cfis’ Safety Behaviors At Flight Training Schools: Understanding The Effects Of Personality Traits, Self-Efficacy, Risk Perception, And Safety Climate, Vivek Sharma

Theses and Dissertations

The purpose of the current study was to investigate the relationship between personality traits, affective domain variables, safety climate, and safety behaviors of certified flight instructors (CFIs). Personality traits consisted of the five dimensions of the Big Five personality model, including Extraversion, Neuroticism, Agreeableness, Openness, and Conscientiousness. Affective domain variables included self-efficacy and risk perception. The study used an explanatory correlational design to determine the relationship between the targeted factors and safety behaviors. The dependent variable was CFIs’ safety behaviors. The sample consisted of 134 CFIs who completed all of the study’s protocols. Participants were obtained from a professional flight …

High-Level Requirements For Conceptual Design Of Bridge Deflection Measurement System Using Model-Based Systems Engineering, Mariana Villalabeitia Arenas

Theses and Dissertations

Bridges are essential in the infrastructure transportation system. Repairs and maintenance are the key activities to keep them safe for use. Over the years, the evolution of technology has been applied to improve the way bridges are designed, built, monitored, inspected, and repaired. Nevertheless, there is still a gap between the research efforts and the application of this knowledge in the practical field of bridge inspections. Model-based Systems Engineering is a formalized methodology in the system design that is centered around the model throughout all the life cycle stages of a system, supporting the requirements, design, analysis, verification, and validation …

Anti-Doping Crisis In Sports, What's Next? Ion Mobility-Mass Spectrometry For The Study Of Anabolic Androgenic Steroids, Diana Constanza Velosa

Theses and Dissertations

The main objective of this work is to augment both qualitative and quantitative measures of anabolic androgenic steroids (AAS) with ion mobility-mass spectrometry (IM-MS), laying the foundation for implementation into analytical drug testing laboratories. AAS testing requires high sensitivity and specificity. IM-MS is presented as an emerging technology workflow capable of targeted quantification of AAS and structural elucidation for potential unknowns, allowing ions to be separated and characterized based on their rotationally averaged collision cross section (CCS). Chapter 1 provides a background of the basic principles of IMS and the different types of analytical methods used for doping analysis currently …