Digital Commons Network^™

Insights Into Androgen Receptor Allosteric Modulation By P,P'-Dichlorodiphenyldichloroethylene Binding At The Binding Function-3 Site And Site-Specific Binding Function-3 Mutations, Emanuel Aggeo Flores

Theses and Dissertations

One of DDT’s metabolites, p,p’-dichlorodiphenyldichloroethylene (DDE), has been classified as an endocrine disrupting chemical (EDC) due to its ability to interfere with hormone signaling by binding to nuclear receptors (NR) such as the androgen receptor (AR).

Structurally, the AR contains a ligand-binding domain (LBD) where endogenous steroids bind. Furthermore, the LBD contains a surface binding site known as binding function-3 (BF-3), which studies suggest exerts an allosteric effect on bound DHT when small, hydrophobic molecules bind.

Here, we present a study that examines how specific BF-3 site mutations and DDE binding affect steroid stability within the LBP utilizing computational methods. …

I Am Still Learning, Too!: Pre-Service Teachers' Experiences Of Mathematics Anxiety In An Inquiry-Based Mathematics Education Course At Utrgv, Jeremiah James Adriano Dela Rosa

Theses and Dissertations

Mathematics anxiety is a prevalent issue in mathematics education that negatively impacts students’ learning, performance, and engagement in mathematics. Prior research suggests that mathematics anxiety is often shaped by students’ experiences and emotional responses within the classroom environment.

The purpose of this study is to explore how Pre-Service Teachers experience mathematics anxiety in an Inquiry-Based Mathematics Education (IBME) classroom. This study employed a qualitative research design supported by descriptive survey data collected through the Abbreviated Mathematics Anxiety Scale (AMAS), selected components of the Fennema-Sherman Mathematics Anxiety Scale (FSMAS), and semi-structured interviews. The survey instruments were used to provide descriptive background …

A New Approach To Generate Combinatorial Patterns In Logical Analysis Of Data And Its Application To Predict College Retention, Salihah Ahmed E. Jaafari

Theses and Dissertations

Student retention and degree completion remain central challenges for higher-education institutions, with significant implications for student success, institutional effectiveness, and public accountability. While advances in predictive analytics have enabled earlier identification of students at risk of withdrawal, many commonly used machine learning approaches suffer from limited interpretability, constraining their practical usefulness for advising, intervention, and policy decision making. This dissertation addresses the problem of predicting student persistence by developing and evaluating optimization based, interpretable classification models within the Logical Analysis of Data (LAD) framework. Building on existing LAD formulations, this research introduces two novel pattern generation models, the Best Term …

Hdra-Fusion: Hybrid Detection With Routed Architecture For Manipulation-Aware Ai Face Forgery Detection, Omar Ebeid

Theses and Dissertations

With the rapid advancements in artificial intelligence-based image generation and manipulation tools, it is extremely difficult to detect if an image is genuine or artificially crafted. Despite extensive research in this area, existing image detection systems suffer from three major problems: suboptimal cross-dataset generalization due to shortcut learning of dataset-specific patterns, unreliable probability estimates due to domain shift, particularly in cross-manipulation evaluation settings, and an inability to detect images manipulated by multiple types of manipulations within a single detection framework. To address these limitations, we propose HDRA-Fusion (Hybrid Detection with Routed Architecture), a framework built on the conclusion that different …

Design And Simulation Of Anti-Resonant Hollow-Core Fiber For Sensing Applications, Pravallika Kante

Theses and Dissertations

This thesis presents the design and simulation of an 8-tube single-ring anti-resonant hollow-core fiber for sensing applications, with particular emphasis on methane gas detection at the fundamental absorption wavelength of 3.3 µm. Conventional solid-core silica optical fibers exhibit strong multi-phonon material absorption beyond 2.5 µm, rendering them fundamentally unsuitable for efficient light guidance and direct gas sensing at mid-infrared wavelengths. Anti-resonant hollow-core fibers overcome this limitation by guiding light predominantly through an air-filled hollow core via the anti-resonant reflecting optical waveguide mechanism, in which the thin silica glass walls of the cladding tubes act as Fabry-Pérot etalons that confine the …

Hybrid Machine Learning For Zero-Day Malware Detection: An Adaptive Static-Dynamic Analysis Approach, Garrett Farmer

Theses and Dissertations

In an era of swiftly evolving cyber threats, zero-day malware continues to be one of the most challenging classes of attacks to detect and mitigate. Traditional signature-based methods often fail to detect novel malicious code, leaving institutions vulnerable to unknown exploits. This thesis proposes a machine learning (ML)-based framework that is designed to detect unknown malware variants. By combining both static and dynamic techniques, such as file structure exam ination and sandbox-based runtime analysis, this approach aims to successfully capture malicious characteristics. The proposed custom pipeline addresses the computational overhead that is associ ated with deep inspections, outlining a staged …

Comparison Of The Effects Of Participation In Early Childhood Education On Readiness Outcomes, Pre- And Post-Covid-19 In A South Texas District, Maria J. Valadez Gonzales

Theses and Dissertations

This study will investigate and gather quantitative data noting if a learning gap exists when evaluating reading data of students participating in a high-quality learning program in 2020 due to the pandemic. RQ1: What gaps are evidenced by progress monitoring TPRI/TJL data from 2019 Beginning of Year (BOY) Kinder pre-pandemic when compared to 2020 post-pandemic BOY data in First grade for educationally disadvantaged students in a South Texas school district? RQ2: Do students who attend these ECE high quality prekinder programs show differing levels of academic achievement utilizing progress monitoring assessments in reading for Kinder – First grades (Wyse et …

Combinatorial Statistics Witnessing An Infinite Family Of Congruences For A Sum Of Partition Functions, Jena M. Gregory

Theses and Dissertations

In 2007, Kronholm established The Interval Theorem, infinite families of congruences in arithmetic progression, modulo any prime ��, for ��(��, ��), the function enumerating the partitions of �� into parts whose sizes come from the set {1, 2, … , ��}. In 2022, Eichhorn, Kronholm, and Larsen proved there are combinatorial statistics described in terms of the multiplicities of the part sizes that witness Kronholm’s Interval Theorem. Here, “witness" means given a congruence of the form ��(��, ��) ≡ 0 (mod ��), we can use these statistics to classify the set of partitions of �� into �� equally sized subsets …

Overreliance On Standardized Testing And Its Impact On The Classroom Experience, Cassia Guajardo

Theses and Dissertations

High-stakes standardized testing has become a dominant force in U.S. education system, shaping curriculum, pedagogy, and accountability systems in ways that can narrow instructional breadth and constrain teacher autonomy. This study examined how these dynamics are experienced by educators working in a predominantly Latinx, border-region district in South Texas. The purpose was to explore K–12 teachers lived experiences with standardized testing and their perceptions of its effects on curriculum, teaching methods, and classroom assessment practices within McAllen Independent School District (ISD).

Using a basic qualitative design, data was collected through an anonymous, open-ended questionnaire. Twenty-five practicing teachers from elementary, middle, …

Faculty Perspectives On Co-Teaching Mathematics: A Focus On Corequisite Education, Aleksandra Shchelkunova

Theses and Dissertations

This study aimed to contribute to the literature by expanding the knowledge on coteaching practices to the area of higher education. Traditionally, co-teaching was considered uncommon in college courses. However, with the increasing popularity of corequisite courses - often structured as linked classes taught by two different instructors - co-teaching has become a new popular trend in higher education. In this research, I compared co-teaching models utilized in K-12 settings with those applied at the college level mathematics courses and analyzed the reflections of faculty members who have experience with team teaching.

This qualitative single-case study was conducted using convenience …

General Chemistry Students' Perceptions Of How Various Course Resources Affect Their Learning And Exam Preparation, Jennifer Scoggin Cortez

Theses and Dissertations

The tertiary-level first-semester general chemistry course has a large range of material with different complexities that can be difficult for students to master within one semester. In the general chemistry I course under study here, students were provided with a variety of resources to help with their learning and understanding, with various components of the course, including the lecture, online textbook, Peer-Led-Team-Learning (PLTL) study sessions, and exams, having associated resources. This study aims to analyze students’ experiences with these various resources. Students were given semi-structured interviews where they talked about their experiences with the resources and provided insight into more …

Bounding The Average Kissing Number, Including New Bounds For Three-Dimensional Binary Sphere Packings, Mark William Bockhaus

Theses and Dissertations

The average kissing number is defined as the supremum over all sphere packings of the value: two times the number of tangencies divided by the number balls in the packing. In this paper, we present a survey of the literature about bounding the average kissing number, beginning with the first non-trivial results, through the most up-to-date bounds. We then turn our focus to binary sphere packings: those which contain spheres of two different radii. We improve upon known bounds for the average kissing number for binary sphere packings in three-dimensions and find exact bounds for many packings.

Assessing Water Quality And Nitrogen Dynamics In Bahia Grande, Texas Using Field And Remote Sensing Data, Sk Taufiqul Islam

Theses and Dissertations

An 8,220-acre estuary in South Texas, Bahia Grande has recently been restored from a disconnected hypersaline basin to a tidal estuary. A spatially explicit water quality index (WQI) was developed and in situ physicochemical data coupled with remote sensing data from Sentinel-2 were used to determine ecological integrity. A WQI from 29.45-53.20 yielded a spatial distribution of water quality that displayed a non-linear spatial trend throughout the estuary. Water quality close to the Brownsville Ship Channel inlet yielded values of 'Moderate/Stressed' water quality (> 50). These areas represent local zones of disturbance where ammonium concentrations were more than 11 µmol/L. …

Curriculum, Power And Pedagogical Becoming: An Autoethnographic Inquiry Into Lived Curriculum, Teacher Agency And Institutional Constraints, Norma Ochoa Urban-Palomarez

Theses and Dissertations

My dissertation, Curriculum, Power, and Pedagogical Becoming, examines the complex relationship between institutional curriculum structures, teacher agency, and the lived realities of classroom practice within U.S. public schooling. Situated at the intersection of curriculum theory and critical pedagogy, the study investigates how power operates through scripted curricula, pacing mandates, and fidelity-driven instructional models, and how these mechanisms shape pedagogical decision-making, professional identity, and the educational experiences of Hispanic students of poverty, language, and color. While standardization is frequently framed as a vehicle for equity and accountability, this research explores how institutional constraints may simultaneously regulate teacher practice and delimit possibilities …

Elementary Teachers' Culturally Responsive Strategies For Fostering Critical Thinking In Science Instruction With Emergent Bilinguals, Lydia Stella Ratel

Theses and Dissertations

This phenomenological study explored the lived experiences of bilingual and English as a Second Language (ESOL)-certified elementary teachers as they fostered critical thinking among emergent bilingual (EB) students in grades 3–5 science classrooms. Grounded in culturally responsive pedagogy, translanguaging, funds of knowledge, and critical thinking theory, the study examined how teachers made sense of instructional decision-making and EB students’ scientific reasoning within accountability-driven educational contexts.

Data were collected through in-depth, semi-structured interviews with elementary teachers serving emergent bilingual students in South Texas public schools. Phenomenological analysis was used to identify shared meanings across participants’ descriptions of instructional practices, language use, …

Bayesian Change-Point Detection In Stock And Cryptocurrency Markets Using Shrinkage Priors, Yosalin Sanchez

Theses and Dissertations

Financial markets often undergo abrupt structural changes driven by political, economic, and geopolitical events, leading to substantial volatility. Detecting such change-points is crucial for identifying structural breaks, improving risk management, and enhancing forecasting performance in financial time series. This study proposes a Bayesian change-point detection framework that incorporates both the t-shrinkage prior and the Horseshoe shrinkage prior. These priors enforce strong regularization on successive differences in mean parameters, enabling the identification of piecewise constant structures in time series data. Posterior inference is conducted using Markov Chain Monte Carlo (MCMC) methods, specifically a Gibbs sampling algorithm, which iteratively samples from the …

Vision-Based Vibration Monitoring Of Civil Structural Damage Detection Using A Low-Cost Autonomous Uav, Javier Antonio Becerril

Theses and Dissertations

This thesis presents the development and experimental validation of a low-cost autonomous unmanned aerial vehicle (UAV) for non-contact vibration-based structural damage detection. We extract structural vibration signals directly from video recordings captured by the onboard camera during flight. The extracted vibration signals are analyzed in the frequency domain to identify natural frequency shifts associated with structural degradation and damage.

To evaluate the effectiveness of the proposed approach, a laboratory-scale steel frame structure is tested under both healthy and simulated damage conditions. In contrast to advanced commercial UAV inspection systems, the developed UAV achieves comparable inspection capability at a significantly lower …

Pesticides And Poverty: How Socioeconomic Factors Relate To Pesticide Application In The Continental Us, Reed Smetter

Theses and Dissertations

Pesticides are often used to help reduce the populations of weeds, insects, and pathogens in agricultural and urban settings, reducing the risk of outbreaks and losses of agricultural yield. The communities that surround agricultural areas often bear the brunt of the negative community and environmental health effects of these chemicals, and are frequently rural, poor, and lack critical infrastructure resources. Pesticide application volumes are often linked closely with specific health effects. In this study, I apply social vulnerability theory to compare the potential connections between the application rates of pesticides and socioeconomic variables across the United States using a nationwide …

A Visit-Count-Based Complete Foraging Strategy For Robot Swarms, Arturo Yahir Gonzalez

Theses and Dissertations

Swarm robotics systems often rely on a balance between exploration and exploitation to perform tasks like Central Place Foraging. While exploitation methods such as pheromone trails and site fidelity are well-studied, the efficiency of the underlying random search exploration remains a challenge, frequently leading to redundant coverage and wasted time as multiple agents repeatedly search the same fruitless areas. This thesis introduces a memory-enhanced exploration strategy designed to improve the efficiency of random search in a swarm of simple robots.

In our proposed algorithm, each robot, constrained with limited memory, periodically logs its recent locations while exploring. This spatial data …

Spatiotemporal Evolution Of Flow Decline And Water Consumption In A Highly Regulated Transboundary River: The Lower Rio Grande/Bravo, Ana Yarely Casillas Rodriguez

Theses and Dissertations

Long-term flow variability in transboundary rivers reflects the combined influence of water availability, infrastructure development, and binational water use. Integrating historical discharge with evolving water-use data remains challenging due to fragmented records and nationally bounded assessments. This study reconstructs a 125-year discharge record (1900–2025) from historical Water Bulletins and modern observations at 12 gauging stations, providing a spatiotemporal assessment of flow evolution and water-budget components in the Lower Rio Grande/Bravo (LRG).

Discharge records were grouped into four hydrologic regimes—natural (1900–1913), pre-dam (1935–1950), post-dam (1974–1989), and modern (2010–2025)—and analyzed alongside binational water-use data across major sectors. A basin-scale water budget, using …

Leading For Impact: An Explanatory Sequential Mixed Methods Study On Leadership Actions Driving Academic Gains Beyond Mock Projections, John Martinez

Theses and Dissertations

This study examined how principals lead schools to achieve academic outcomes that exceed projected performance. Using an explanatory sequential mixed methods design, the study first identified campuses that demonstrated statistically significant improvement between projected outcomes based on mock assessments and actual performance on state accountability measures. Quantitative analyses, including paired-samples t-tests, repeated measures ANOVA, and correlation analyses, revealed significant differences between projected and actual outcomes, variation across assessment cycles, and increasing alignment between mock and summative assessments over time. Standardized mean difference scores were used to identify campuses that demonstrated the greatest positive deviation from projected performance.

In Phase 2, …

Probing The Dynamic Behavior Of The Androgen Receptor In The Presence Of Heptyl And Methyl Parabens, Edgardo De Leon

Theses and Dissertations

The androgen receptor (AR) mediates physiological signaling from endogenous androgens, a function that can be disrupted by endocrine disruptors with serious reproductive and developmental consequences. Parabens, widely used preservatives, inhibit AR signaling in cell-based assays, with inhibitory potency correlating with alkyl chain length: heptylparaben exhibits stronger antagonism than methylparaben, which shows no effect. We hypothesize this differential potency arises from allosteric modulation at the AR Binding Function 3 (BF-3) site, altering dihydrotestosterone (DHT) binding dynamics. Docking calculations using antagonist-bound AR crystal structures, followed by molecular dynamics simulations, show that methylparaben fails to remain bound at BF-3, whereas heptylparaben maintains stable …

Morphological Evolution And Sediment Budget Of A Flood-Tidal Delta On The Rio Grande Delta Plain: Bahia Grande, Texas, Usa, Aleen Pertuz Paz

Theses and Dissertations

The Isabel Delta is a recently formed flood-tidal delta within the restored Bahia Grande system on the Rio Grande Delta Plain, Texas, USA, where renewed tidal connectivity has created conditions for rapid sediment buildup and landform evolution. This study quantified morphological changes from 2008 to 2025 using satellite imagery. It assessed sediment retention by comparing the effective sediment discharge required to reproduce observed delta growth with field-based estimates of sediment supply derived from channel hydrodynamics, cross-sectional area, and suspended sediment concentration. The delta expanded steadily throughout the study period, with increases in bar, channel, and total surface area, and an …

On The Structure Of The Homotopy Lie Algebra Of Local Rings, Dawson M. Strong

Theses and Dissertations

This thesis investigates the construction and homological properties of the homotopy Lie algebra π(R) of a commutative local ring (R,m,k). Drawing upon the theoretical framework of differential graded (DG) algebras, we first establish the theory of minimal free resolutions and other standard topics in homological algebra. The core of this work details the iterative construction of the acyclic closure R⟨Y⟩ of k over R, which is achieved by the systematic adjunction of exterior and divided power variables to eliminate cycles in homology. We demonstrate that this acyclic closure serves as a minimal free resolution and provides the means to define …

La Panza: Un Acto De Rebeldia Para Los Atravesados Y Los Que Siguen Despues / The Panza: An Act Of Rebellion For The Inbetweeners And Those Who Follow After, Abigail Guadalupe Cantu

Theses and Dissertations

Our ancestors, family members, and ourselves that live in the borderlands have embodied knowledge, and/or an innate intuition that comes from the pit of our soul, particularly from our “panza”; hence, the creation of a panza consciousness as the focus for my thesis. I’m trying to “rediscover” the embodied knowledge that has been taken from us and how we can learn to harness these forms of knowledge into a societal shift ( i.e. how we interact with others, how we see our bodies, how see the creation of knowledge, and how we see the world). Although, Eurocentric ideals sought to …

Accurate Polyp Segmentation With Visual Mamba, Diego Adame

Theses and Dissertations

Medical image segmentation is a fundamental task in computer-aided diagnosis because it enables precise delineation of anatomical structures and pathological regions from clinical images. While convolutional neural networks and Transformer-based models have achieved strong performance on many medical segmentation benchmarks, CNNs struggle to model long-range dependencies and Transformers often incur high computational complexity for high-resolution medical images. Recently, state space models have emerged as an efficient alternative for dense prediction tasks due to their ability to capture long-range dependencies with linear complexity. However, existing Mamba-based segmentation models still rely on pixel-wise raster scanning that disrupts spatial locality and use simple …

A Case Study Of One-To-One Mobile Teaching And Learning Environments Measuring Creativity In A Rural Elementary School In Deep South Texas, David Warren Hernandez

Theses and Dissertations

This qualitative case study examined how creativity is enacted within rural one-to-one mobile teaching and learning environments in Deep South Texas. Grounded in the frameworks of mobile learning affordances (Klopfer et al., 2002), the Technological, Pedagogical, and Content Knowledge (TPACK) framework, and the SAMR model, the study explored how instructional practices, student agency, and contextual conditions influenced creative learning experiences in an elementary school setting. Data were collected from five elementary teachers at a rural South Texas district and included semi-structured interviews, classroom observations, and samples of student-created artifacts. Data analysis followed a systematic process of first-cycle coding, second-cycle axial …

Soil Water Content Beneath Agrivoltaic Installations In A Subtropical Semi-Arid Climate, John Justin Rodriguez

Theses and Dissertations

Agrivoltaics (AV) not only beneficially influences agricultural microclimates in the field, AV systems can generate on-site energy to offset operational costs, diversify income sources, and improve overall resilience, while providing environmental co-benefits such as reduced heat stress on plants and improved resource use efficiency. This thesis evaluated agrivoltaic shading effects on SWC and soil temperature using high-resolution in situ measurements collected over one year in an active vineyard, incorporating row type, soil depth, shading, and time of day. With precipitation as the primary water source, shaded soils exhibited up to 24.53% lower SWC relative to sun-exposed soils, likely due to …

Multivariate Time-Series Forecasting Of 24-Hour Ambulatory Blood Pressure Using Long Short-Term Memory And Temporal Fusion Transformers, Sebastian Alejos Torres

Theses and Dissertations

Time series play a central role in healthcare by enabling continuous patient monitoring and forecasting of physiological and clinical measurements. Traditional models, such as autoregressive integrated moving average (ARIMA), are limited in capturing nonlinear dynamics and irregular sampling. In this study, we develop and evaluate Long Short-Term Memory (LSTM) networks and Temporal Fusion Transformers (TFTs) to forecast 24-hour ambulatory systolic and diastolic blood pressure (SBP and DBP) time series enriched with demographic and clinical features. Mean absolute error (MAE), root mean squared error (RMSE), mean absolute percentage error (MAPE), and R² were used to evaluate predictive accuracy and temporal pattern …

Structure–Property Engineering Of Sn-Based Hybrid Perovskites Via Bulky Organic Cation Incorporation: From 3d To 2d Architectures, Kevin Alejandro

Theses and Dissertations

This thesis investigates tin-based hybrid organic/inorganic perovskites (HOIPs) as a lead-free alternative to silicon solar cells. To manipulate optoelectronic and efficiency of the semiconductors, methylammonium was substituted with bulky propylammonium and tetrabutylammonium cations to induce quasi-2D/3D Ruddlesden-Popper phases. X-Ray Diffraction confirmed 2D layered phases in propylammonium hybrids (5-15%), while tetrabutylammonium hybrids faced steric limits, triggering vacancy ordered perovskite phases at 1% concentration. Optical analysis showed a bandgap narrowing from 1.30 eV to 1.26 eV with increased substitution. Although photovoltaic performance generally declined, the 10% propylammonium hybrid achieved the highest fill factor of ~0.79, indicating superior internal charge transport. This work …