Digital Commons Network^™

Cyberbullying And Mental Health Issues Among University Students, Brandi N. Cruz

Theses and Dissertations

According to the CDC (2024), bullying can lead to social and emotional distress, self-harm, and death. Bullying can also increase the risk for depression, anxiety, and poor academic achievement. The increased use of social media and the rise in cyberbullying (CB) and related mental health concerns among emerging adults is highly disconcerting, especially given their propensity for mental health problems. The purpose of this study is to increase the understanding of young university students’ perceptions about CB victimization and whether CB affects their mental health. A cross-sectional research design was used to conduct the study. In this study the number …

A Study Of Preferred Modality Of Education And Perceptions Of Academic Success Of Post 9/11 Student Veterans, Jason R. Wakefield

Theses and Dissertations

Veterans are pursuing higher education at increasing rates due to the benefits available upon separation or retirement from military service. Many choose online programs for flexibility, while others prefer traditional, in-person instruction. Regardless of modality, student veterans often face significant challenges completing their degrees. “When student veterans first enter college, they must transition to the overwhelming, independent, and fast-paced lifestyle of a college student” (Semer & Harmening, 2015). While online learning may contribute to these difficulties, other factors also hinder success.

Colleges and universities continue to explore why student veterans struggle to complete their programs, yet underlying issues may distort …

The Influence Mechanism Of Chief Sustainability Officers On Firm Sustainability Performance, Taiwo Abraham

Theses and Dissertations

This dissertation examines how Chief Sustainability Officer (CSO) human capital configurations influence organizational sustainability performance through a configurational approach. Drawing on Upper Echelons and Human Capital theories, the study conceptualizes CSO human capital as encompassing both general (GHC) and sustainability-specific (SHC) dimensions that interact with job functions and governance mechanisms to shape outcomes. The theoretical framework proposes that SHC primarily influences non-financial sustainability performance (nfSP), while GHC drives financial sustainability performance (fSP). Champion functions moderate the SHC-nfSP relationship, while Ambassador functions moderate the GHC-fSP relationship. Firm sustainability governance further enhances these relationships and creates pathways for SHC to influence financial …

Characterizing The Germination Process And Establishing Best Practices For Seed Propagation Of Tamaulipan Thornscrub Species For Habitat Restoration, Saroj Dhakal

Theses and Dissertations

Tamaulipan thornscrub is an imperiled plant community of southern Texas and northeastern Mexico. Given its importance for biodiversity conservation, stakeholders have been involved in restoration programs using seedlings grown from wild seeds. However, stakeholders often report that insufficient seedling supply is a challenge. To address knowledge gaps in seed germination behavior limiting seedling production, this study was conducted on 18 Tamaulipan thornscrub species, identified by growers as difficult to germinate. Seeds of all studied species are orthodox except Amyris texana, which have recalcitrant properties. Nine species have physical dormancy that was successfully addressed with mechanical and/or chemical scarification. Other species …

Navigating Cultural And Professional Identities: A Study Of Hispanic Women's Experiences In Aerospace Internship Programs, Jennifer Becerra

Theses and Dissertations

This phenomenological study investigated how Hispanic women navigated cultural identity and professional development during National Aeronautics and Space Administration (NASA) internship programs, examining the role of culturally responsive mentoring in supporting retention. The research question was, How do Hispanic women in aerospace-internship programs navigate the intersection of cultural identity and professional development as they transition from academic science, technology, engineering, and mathematics (STEM) programs to aerospace careers, and what role does culturally responsive mentoring play in supporting their retention?

Using Anzaldúa’s nepantla concept, Duncan-Andrade’s critical-hope theory, and Ladson-Billings’ culturally relevant pedagogy as theoretical frameworks, in this study, I employed semistructured …

Arthropod Communities Associated With Endangered Physaria Thamnophila (Zapata Bladderpod) And Its Nurse Plants, Cesar Adrian Hinojosa

Theses and Dissertations

Physaria thamnophila is a federally endangered plant whose associated arthropods are understudied and poorly understood. This study surveyed environmental conditions and the arthropod community within the Arroyo Ramirez Tract of the Lower Rio Grande Valley National Wildlife Refuge, assessed which environmental factors influenced the arthropod community, and sought arthropod taxa statistically associated with Physaria thamnophila. Sticky cards and pitfall traps were deployed for a 7 day period, and vacuum samplings occurred quarterly over the span of a year to collect arthropods that were identified to order and family level for Coleoptera, Hymenoptera, and Lepidoptera. Biotic and abiotic surveys were performed …

Collective Agency And Community Resilience Among Farmworkers In The Lower Rio Grande Valley, Angel Velazquez

Theses and Dissertations

This research assesses how farmworkers in the Lower Rio Grande Valley of Texas use everyday practices to build resilience and adapt to changes in their lives. I apply two interconnected theories, White’s (2017, 2019) framework of collective agency and community resilience and Castro and Sen’s (2022) framework of everyday adaptation actions, to study these practices. I conducted 19 semi-structured interviews with Latino farmworkers and professionals who work with local farmworker organizations in the Rio Grande Valley (RGV) of Texas. Interview transcripts were analyzed to determine if and how Latino farmworkers in the RGV can work towards community resilience and implement …

Determination Of An Effective Natural Boxelder Bug (Boisea Trivittata) Repellent, Reyna Chavez

Theses and Dissertations

This study investigates the use of ecofriendly repellant alternatives to pest management to control boxelder bugs (Boisea trivittata). This bug gathers by the thousands on warm surfaces of exterior suburban homes during early fall and late spring. I determined bug repellency to turmeric oil (Curcuma longa), catnip (Nepeta cataria), citronella (Cymbopogon nardus), and lavender (Lavandula angustifolia). The treatments consisted of essential oils containing 20% methanol. All treatments demonstrated repellency of Boxelder bugs. Citronella was the most effective and had the highest level of repellency range of 90-99%. Catnip was the least effective with a repellency range of 63-82%.

Burdened By Conviction: The Pressures Within, Dulce M. Perez

Theses and Dissertations

This thesis investigates how religious and political systems, particularly Catholic influences in the Rio Grande Valley, limit and silence women. By employing historical and alternative photographic techniques such as cyanotype, gum bichromate, and photo transfer, I express how these systems control and shape women’s lives. Combined, the materials serve as a metaphor for the oppression and damage which power can inflict. In these works, fabric represents the potential for manipulation of the human mind; the red thread stitched through cloth and paper symbolizes control; and fragmented images are a reference to the collapse of humanity. Throughout this exploration, I reflect …

Decolonizing The Whitexican: Reclaiming Identity Through Nahuatl And Mesoamerican Motifs, Laia Ivanna Vite Cano

Theses and Dissertations

This thesis explores the intersection of art, linguistics, and ideography through the lens of personal and cultural heritage rooted in the Huasteca region of Central Mexico. Drawing inspiration from familial connections to the pueblos of Huazalingo and Huejutla in Hidalgo, Mexico, the research examines the cultural complexities of bicultural and binational experiences. It is grounded in the theoretical framework of Nepantla, a concept introduced by Gloria Anzaldúa to describe the unseen space of the border life as one of existing between worlds, identities, and cultures. Included and essential to this work is the Coyolxauhqui Imperative, which informs the process of …

Clustering 24-Hour Ambulatory Blood Pressure Time Series With Dynamic Time Warping And Time Warp Edit Distance, John Knight

Theses and Dissertations

Ambulatory blood pressure monitoring (ABPM) captures dynamic circadian changes in blood pressure (BP) that are not reflected in static clinic readings. This study applied time-series clustering with two elastic distance measures—Dynamic Time Warping (DTW) and Time Warp Edit Distance (TWED)—to identify distinct phenotypes in 2,155 24-hour ABPM time series from participants in the Maracaibo Aging Study. DTW and TWED both yielded three clusters corresponding to non-dipping, moderate-dipping, and strong-dipping patterns. The non-dipping group showed elevated nighttime BP, associated with greater cardiovascular and cognitive risk, while the strong-dipping group was associated with higher education and younger age in baseline clinic measurements. …

A Picture Tells A Thousand Words—, But Ecg Signals Have More To Say, Ashley N. Gomez

Theses and Dissertations

With the increasing adoption of deep learning classification models in the medical domain, a critical challenge remains: achieving high predictive accuracy while maintaining clinical Inter-pretability. This study examines how model architecture, dataset origin, and the use of full versus subset data affect both classification performance and Interpretability in Electrocardiogram (ECG) signal analysis. ResNet18 is evaluated using an open-source ECG Image Dataset, thus a custom dataset derived from digitized ECG images. Post-hoc explainability methods, such as Integrated Gradients, are applied to determine which time steps have the most significant influence on model decisions. The findings demonstrate that model architecture and dataset …

Cyberbullying Victimization And Suicide Behavior: The Roles Of Social Anxiety And Body-Related Comparison Among Young Latina Adults, Monica Elena Ochoa

Theses and Dissertations

Suicide behavior rates have increased over the years in the United States among Latinas and adolescents/young adults. Previous research has identified relationships between various body-related concerns, (e.g., body dissatisfaction, appearance comparison, and body shame) cyberbullying, social anxiety, and suicidal ideation, yet minimal research has examined the relationship of these factors and how they interrelate to explain suicide risk in Latina young adults. This study investigated whether body dissatisfaction, appearance comparison, and body shame had indirect effects on suicide behaviors through the interaction of cyberbullying victimization in 194 Latina college students. The results of this study found that cyberbullying victimization mediated …

Efficient Self-Supervised Representation Learning For Large-Scale Time Series Classification, Kevin Garcia

Theses and Dissertations

Recently, there has been a significant advancement in designing Self-Supervised Learning (SSL) frameworks for time series data to reduce the dependency on data labels. Among these works, hierarchical contrastive learning-based SSL frameworks, which learn representations by contrasting data embeddings at multiple resolutions, have gained considerable attention. Due to their ability to gather more information, they exhibit better generalization in various downstream tasks. However, when the time series data length is significant long, the computational cost is often significantly higher than that of other SSL frameworks. In this paper, to address this challenge, we propose an efficient way to train hierarchical …

Interpretable Alignment Of Textual Weather Reports With Local Sensor Time Series For Extreme Weather Event Visualization, Juan Luis Garza

Theses and Dissertations

This thesis presents an automated and interpretable pipeline that links natural-language weather narratives with local meteorological sensor time series. Using large language models, NOAA-style event reports are transformed into structured records capturing event type, timing, descriptive context, and uncertainty. Each extracted event is aligned with harmonized temperature, precipitation, and wind measurements from nearby weather stations, enabling systematic comparisons between narrative evidence and observed atmospheric conditions.

Across roughly fifty stations and more than two thousand events, the analyses show that discrepancies between narrative descriptions and sensor behavior arise primarily from spatial separation rather than from temporal offsets, sensor preprocessing artifacts, or …

Fractals, Reachability, And Computation In Models Of Dna Self-Assembly And Chemical Reaction Networks, Ryan Arlie Knobel

Theses and Dissertations

This thesis serves as the bridge between results compiled across varying models of tile self-assembly, molecular computation, and game complexity. As such, this thesis is broken into three chapters. In the first part, we show how to generate any Discrete Self-Similar Fractal (DSSF) with a feasible generator in the seeded Tile Assembly model, a model limited to single tile attachments and pairwise state transitions. In the next part, we study models of molecular computation, where we consider the problem of reachability in Chemical Reaction Networks and similar model extensions. The final part is a game-complexity analysis of Celtic! and k-ago, …

Ai-Driven Electromagnetic Design And Performance Prediction Of Microstrip Antennas, Eduardo Javier Vazquez

Theses and Dissertations

This thesis investigates the application of Deep Learning to automate and accelerate microstrip antenna inverse design. The initial investigation was to predict microstrip antenna performance from its geometry parametric input, and found out that forward prediction with adopted geometric representation results in ill-posed scenario, high ambiguity and unstable mapping. The study later mostly focuses on the inverse prediction by machine learning from S11 parameter input to predict antenna patch geometry parameters instead.

A dataset of 5,000 ANSYS HFSS simulated antennas (later filtered to 4,136 valid samples) was generated using cubic spine -described geometry profiles. Multiple neural architectures were adopted for …

Boundary-Layer Mechanisms In Flow Over Triangular Porous-Textured Flat Plates: A Computational Fluid Dynamics Study, Luis Angel Alvarez

Theses and Dissertations

Growing demand for energy-efficient vehicles drives research into flow control strategies that mitigate aerodynamic drag. Active devices such as morphing flaps or plasma actuators offer real-time authority but require external power. Passive concepts, including riblets, tubercles, porous coatings, and miniature vortex generators, reshape the boundary layer without additional energy input. We propose an integrated passive solution called Triangular Porous Texturing (TPT). TPT combines the two mechanisms: a periodic array of triangular prisms that generate controlled streamwise vortices, and an embedded porous matrix that locally adjusts pressure gradients near the wall. Acting synergistically, these features attenuate near-wall turbulence, redistribute momentum, and …

Design And Evaluation Of Gamified Kahoot Modules For Improving Engagement And Conceptual Understanding Of Introductory Physics Students, Yaritza Villarreal

Theses and Dissertations

This study investigates the effectiveness of gamified learning modules in enhancing the engagement and conceptual understanding of introductory physics students. The first phase of this study focused on the design and development of gamified learning modules for selected topics in introductory physics. The modules were developed by integrating principles of Backward Design, following an escape-room theme with interactive scenarios, and incorporating classic game elements (e.g., points and leaderboards).

The second phase examined the effectiveness of the gamified Kahoot modules using a pretest-posttest control-group design. Sixty-eight (68) students were equally randomly assigned to the control and experimental groups. The experimental group …

Seagrass Preference Among Pinfish In The Lower Laguna Madre, Nathaniel Garza

Theses and Dissertations

Pinfish (Lagodon rhomboides) is a common estuarine fish species found from Massachusetts to the Yucatan, Mexico. As juveniles, pinfish spend a significant portion of their life in coastal seagrasses which provide both shelter from predators and food. Along the Texas coast, there are three major species of seagrass- turtle grass (Thalassia testudinum), manatee grass (Syringodium filiforme) and shoal grass (Halodule wrightii) that differ in structural complexity. The goal of this study was to determine if pinfish associate more with one seagrass species than the others. A year-long field study was completed using twelve sample sites in the Lower Laguna Madre, …

Interactive Effects Of Nutrient Loading And Hyposalinityon The Physiological Responses Of The Red Macroalga Gracilaria Tikvahiae, Donavuan Vincent Salazar

Theses and Dissertations

Coastal macroalgae face anthropogenic stressors such as nutrient enrichment from nitrogen fertilizers and reduced salinity linked to flooding. The physiological impacts of these combined stressors remain unclear. This study examined interactive effects of nitrogen loading and hyposalinity on Gracilaria tikvahiae through a 9‑day laboratory experiment. Samples experienced declining salinity (35–0 ppt) with nitrate or ammonia enrichment (120 µmol/L). Measurements included primary production, respiration, biomass, nitrate uptake, and chlorophyll‑a. Hyposalinity significantly reduced physiological performance, with gross primary production declining over 100%, chlorophyll‑a content 25–45% lower, biomass loss, and reduced nitrogen uptake. Nitrogen enrichment failed to mitigate the adverse impacts under hyposaline …

Bacillus Subtilis: A Bacterium That Can Potentially Degrade Low-Density Polyethylene (Ldpe) And Polyethylene Terephthalate (Pet), Migdalia Flores

Theses and Dissertations

The widespread application and disposal of plastics, such as low-density polyethylene (LDPE) and polyethylene terephthalate (PET), have raised significant environmental health concerns. Because of each plastic’s stability and durability, these plastics exhibit limited natural degradation in the environment. Recently, the environmentally friendly biodegradation of plastics by living microorganisms has attracted more attention, as they can assist in the natural degradation process. In this study, the bacterial strain Bacillus subtilis ATCC6051 was used to degrade LDPE and PET for 60 days. To measure the degradation of low-density (LDPE) and polyethylene terephthalate (PET), the dry weight was taken, and physical characteristics were …

Connections On Manifolds: A Modern Approach To Classical Differential Geometry, Jed Allen Wilshire

Theses and Dissertations

The purpose of this thesis is to connect modern differential geometry concepts to the classical differential geometry study of surfaces, specifically spheres. This thesis will cover the topics of Riemannian manifolds, tangent spaces, vectors, vector fields, the connection of Levi-Civita, the Christoffel symbols, and Riemannian curvature. Each concept will be demonstrated on the well known unit sphere manifold.

Probing Prebiotic Rna Oligonucleotide Polymerization On A Mg-Fes Catalyst Using Microfluidics, Gabriella Garza

Theses and Dissertations

Non-enzymatic polymerization under aqueous conditions has long been viewed as unfavorable, due to product (H2O) inhibition in abiotic settings (Damer & Deamer, 2015); despite its efficiency in biology through ATP monomer activation. Geochemically sustained pH gradients may provide free energy for condensation of organic monomers (Martin & Russell, 2003). Here, we investigated a biologically analogous non-enzymatic mechanism for RNA oligomerization, by probing the catalytic properties of a Mg-rich FeS mineral under aqueous conditions. FeS minerals promote a diverse prebiotic reaction (Wächtershäuser, 1988) and would have precipitated at Hadean submarine hydrothermal systems (Sojo et al., 2016). Natural pH and redox gradients …

Development And Testing Of A Prototype Erbium-Doped Lithium Tantalate Based Sensor For Infrastructure Crack Detection And Measurement, Alejandro Barrera

Theses and Dissertations

Ensuring the safety and longevity of infrastructure is crucial to safeguarding communities and preserving economic stability. In this study, the development of a novel sensor for detecting and characterizing cracks in infrastructure, particularly suited for deployment on Unmanned Aerial Vehicles (UAVs), is presented. The device utilizes a laser (operating at 980 nm) for excitation of erbium-doped lithium tantalate nanoparticles that emit 1550 nm wavelength, which stimulates a photodiode for data collection. The data was utilized to collect, process, and reconstruct topological information. The synthesized lithium tantalate nanoparticle samples vary in erbium doping percentages of 0.5%, 3%, and 10%. Experimental evaluation …

Population Structure Of Red Drum (Sciaenops Ocellatus (Linnaeus, 1766)) In Two Systems In The Northwestern Gulf Of Mexico, Sandra Antonia Leal

Theses and Dissertations

Red drum (Sciaenops ocellatus) are an economically significant species of fish inhabiting the Gulf of Mexico. There are limited studies assessing S. ocellatus population structure focused on the southern coast of Texas. A total of 1,008 fish were collected over one year on a quarterly basis at South Bay (SB) and Holly Beach (HB) in the Lower Laguna Madre (LLM) of Texas to assess population structure. Juvenile S. ocellatus utilize the water systems of the LLM as a nursery ground and were more abundant at SB (n = 718) than HB (n = 290). The most abundant age classes were …

A Computational Approach To Ramanujan-Type Congruences For Products Of Level 13, Aiden Michael Lalonde

Theses and Dissertations

In this thesis, we find products that are modular forms of level 13 whose Fourier coefficients satisfy certain congruences. These products are constructed in terms of integer powers of Klein forms and the Dedekind eta function. The products that are modular forms for Γ1 (13) have vectors of exponents that are elements of a bounded polytope. A parameterization for this polytope allows us to find a complete set of products that are modular forms for Γ1 (13). The corresponding graded ring of modular forms containing these products is constructed from a finite set of generators. These generators satisfy a finite …

Applicability Of Cementochronology To Estimate Season-Of-Death In Humans: Insights From Modern Documented Collections, Olga Ibarra-Sanchez

Theses and Dissertations

Dental cementum is characterized by lifelong deposition of alternating opaque annuli in fall/winter and translucent bands in spring/summer. This study aims to test the applicability of cementochronology to estimate season-of-death, by observing the properties of the last layer, with direct implications for forensic anthropology and bioarchaeology. The sample includes canine teeth from 146 adults (84 males, 62 females), age-at-death ranging from 20-97 years (mean=61.7 years, SD=18.6 years), from two contemporary skeletal collections. Of these individuals, 78 (53.4%) died in spring/summer and 68 (46.6%) died in fall/winter. Overall accuracy was low at 64.4% (94/146). Accuracy was higher for spring/summer deaths 100.0% …

Feature Extraction From Railroad Bearing Onboard Vibration Sensors Using Machine Learning Models, Diego Cantu

Theses and Dissertations

The University Transportation Center for Railway Safety (UTCRS) has developed an algorithm capable of identifying defective railroad bearings, determining damaged component(s) within, and quantifying severity of the defects. The defect-detection algorithm requires the operating speed as an input, which is not readily available in field operation of onboard sensors. Therefore, onboard sensors deployed in rail revenue service must rely on Global Positioning Systems (GPS) to obtain speed, which can be power-intensive and susceptible to signal interference. This study covers the development of a vibration-based model that extracts operating speed from wireless sensor data to enable fully autonomous onboard diagnostics. Signal …

Érase Una Vez En Tiempos Modernos… Colección De Relatos Reimaginados, Jose Rolando Rivera Jr.

Theses and Dissertations

Esta tesis examina la reimaginación narrativa de cuentos de hadas en diálogo con leyendas urbanas, situados en países hispanohablantes y en contextos históricos específicos, como una metodología crítica capaz de transformar paradigmas culturales, visibilizar voces marginales y cuestionar estructuras hegemónicas. Desde un enfoque interdisciplinario que integra estudios culturales, psicología narrativa y teoría decolonial, se propone entender las historias como sistemas vivos que modelan identidades y configuran memorias colectivas.

La reimaginación se plantea como una forma de intervenir estratégicamente en los relatos heredados mediante operaciones como la deconstrucción, la excavación psicológica y la reubicación cultural. El estudio aborda, además, subgéneros del …