Digital Commons Network^™

An Exploratory Analysis Of Neurocognitive Performance And Posttraumatic Stress Disorder (Ptsd) Among Latinx Asylum Seekers, Elsie A. Arias

Doctoral Dissertations

Asylum seekers are exposed to violence and traumatic events in their home countries at high rates, leading to mental health challenges such as posttraumatic stress disorder (PTSD). PTSD symptoms and comorbidities such as depression and alcohol misuse are associated with impacts to multiple domains of cognitive functioning among populations such as Veterans. However, the neurocognitive performance of Latinx asylum seekers who experience PTSD symptoms are under-documented in the current literature despite its meaningful impact on clinical care engagement and navigation of the legal process. This study utilized an exploratory, quantitative, cross-sectional design to examine whether higher levels of self-reported PTSD, …

Identity Development For Queer East Asian Americans During The Coming Out Process To Family, Mei E. Tam

Doctoral Dissertations

There has been a growing number of Asian Americans who openly identify as queer, with over half a million residing in the United States (UCLA, 2021). Despite this, psychological research has paid limited attention to how queer and Asian American identities intersect and are integrated, often framing them as conflicting while overlooking culturally embedded meaning-making processes. The present study explored identity formation among cisgender queer East Asian Americans during the critical period of coming out to family, focusing on how their understanding of and relationship to their queer and ethnic identities shifted following disclosure.

Using a qualitative approach, semi-structured interviews …

Mathematical Analysis Of Within-Host Models: Viral–Immune Dynamics, Bifurcations, And Disease Severity, Nazia Afrin

Doctoral Dissertations

My research develops and analyzes ODE-based within-host models at multiple scales. Using dynamical systems theory and numerical methods, I study host–pathogen interactions and immune responses, providing insights into disease dynamics and control. The first model describes the complex dynamics of Hepatitis B virus (HBV) infection and addresses the question: what mechanisms determine whether the infection is cleared during the acute phase or progresses to a chronic state? A key feature of this model is the assumption that all classes of liver cells (uninfected, infected, and protected from reinfection) proliferate at different rates. The findings provide insight into two important aspects …

The Impact Of Evolution And Strong Allee Effects On The Dynamics Of A Discrete-Time Predator-Prey System, Neerob Basak

Doctoral Dissertations

This dissertation investigates the dynamics of discrete-time predator-prey systems, focusing on both evolutionary responses and ecological interactions. The first part of this dissertation, in Chapters 2 and 3, explores how evolutionary processes, particularly the development of resistance to toxicants in predators, influence the persistence and stability of predator-prey populations. In this part, we extend the predator-prey model developed in Ackleh et al., 2019 to incorporate the evolution of a predator's resistance to toxicant effects. We consider three cases: (1) lethal effects, where the toxicant directly influences the predator's survival; (2) sublethal effects, where the toxicant impacts the predator's fecundity, and …

An Exploration Of Variables Related To Gender Role Differences And Social Relationships Among Nontraditional Bachelor's Degree Recipients, Cynthia Bourgeois Bergeron

Doctoral Dissertations

The goal of this study was to examine variables that speak to gender role differences among nontraditional bachelor’s degree recipients aged 30 to 49. These issues are particularly relevant given enrollment trends showing that the diversification of bachelor’s degree seekers has outpaced the policies and norms of traditional undergraduate education. A nonexperimental, correlational research design was employed using chi-square tests and Cramer’s V as post-hoc measures on categorical data from the 2012, 2014, and 2016 General Social Survey. Shaped by Gilligan’s moral development theory, several social variables were included in the analysis. Two statistically significant associations emerged: women earning bachelor’s …

A Cross-Sectional Study Of First-Generation College Students' Sense Of Belonging Across Diverse Institutional Contexts, Nirmal Chandra Gope

Doctoral Dissertations

First-generation college students comprise a significant growth demographic in U.S. higher education. Even with lower enrollment rates, more than one-third of U.S. postsecondary school students are first-generation students (Cataldi et al., 2018; Redford & Mulvaney Hoyer, 2017; Ward et al., 2012; Whitley et al., 2018). However, their retention and graduation rates are significantly lower than those of their continuing peers (Choy, 2001; Engle, 2007, 2008; Ishitani, 2006; Longwell-Grice & Longwell-Grice, 2021). Various factors play a significant role in creating this disparity (Longwell-Grice & Longwell-Grice, 2021; Tinto, 1993). Research identifies belonging as a crucial factor influencing student persistence, academic achievement, mental …

The Pie Thief (And Friends): Ethnographic Microanalysis Of Peer Interactions Involving Children With Highly Unintelligible Speech: A Descriptive Study, Katherine Anne Mcquitty Hays

Doctoral Dissertations

This dissertation is an ethnographic microanalysis investigating how children with highly unintelligible speech accomplish a range of social actions when interacting with their peers. Detailed transcription of multimodal communications of peers interacting in the context of a 9-day summer therapy camp yield profiles of two participants of interest, each with approximately 30-40% speech intelligibility. Domain analysis and taxonomy organize data for the purposes of comparative analysis across transcribed durations of peer conversation and peer play. Findings indicate pervasive pragmatic impacts as well as effective uses of multimodal means within interactional frames and schemas. Clinical implications include consideration of AAC optimization …

A Bifurcation Theorem And Its Application To Discrete-Time Models In Ecology And Epidemiology, Jenita Jahangir

Doctoral Dissertations

Matrix models are useful for modeling populations or diseases that involve discrete developmental stages, multiple stages of infection, and interactions among species. To study the coexistence dynamics in matrix models, we extend a bifurcation theorem for resident-invader host-parasitoid type populations by allowing every block of the projection matrix, depending on the bifurcation parameter and the off-diagonal blocks, to be nonzero. As an application, in the first part of the dissertation, we propose a discrete-time host-parasitoid model with stage structure in both species. For this model, we establish conditions for the existence and global stability of the extinction and parasitoid-free equilibria. …

A Qualitative Study: Understanding The Effects Of Acceleration Programs On The Motivation And Burnout Of Students With Gifts And Talents, Destini Duhon Manuel

Doctoral Dissertations

A student that has an advanced gift or talent which encompasses their peers is often raftered to as gifted (National Association of Gifted Children, 2018) and need differentiated instruction and accommodations to reach their full potential (Clevenger, 2022) Research shows high levels of expectations could lead to underachievement (Garn & Jolly 2019; Hornstra et al., 2003), motivation issues (Hornstra et al., 2023), and burnout (May et al., 2020) of students with gifts and talents. Acceleration programs are often used to accommodate students with gifts and talents, but evaluators must proceed with caution and place students in the correct program to …

Fairness-Aware And Efficient Federated Learning Frameworks For Heterogeneous Systems, Simin Javaherian

Doctoral Dissertations

Federated Learning (FL) enables decentralized clients to collaboratively train machine learning models without sharing raw data, making it a promising paradigm for privacy-preserving intelligence across large-scale, heterogeneous systems. However, practical FL environments face significant challenges arising from variations in client resources, participation patterns, client behavior, and data distributions. These challenges often lead to inefficiency, unbalanced contributions, and unfairness, ultimately degrading model performance and discouraging long-term client participation. This dissertation advances the state of FL by developing a unified suite of fairness-aware and efficiency-driven frameworks tailored for heterogeneous environments. We investigate fairness from multiple perspectives, including client selection, contribution weighting, and …

Out There: Notes And Stories A Hybrid Collection With Critical Introduction, Ben Porter

Doctoral Dissertations

This dissertation is composed of two parts: literary criticism and a collection of fiction and lyric essays. Across both sections, it examines the problem of description: how persons make experience, action, and suffering intelligible in language, and what happens when that intelligibility breaks down under historical, social, and familial pressure. The critical essay, “Failed Descriptions and Neoliberal Talk in Don DeLillo’s The Body Artist,” argues that DeLillo represents a crisis of intentional speech under neoliberal modernity, in which public language is narrowed to private affect and meaningful social description becomes increasingly difficult. Reading the novel through philosophers of language and …

Investigations Of Carbon Dioxide Storage In Low-Temperature Reservoirs For Non-Leaking Storage, Md Nahin Mahmood

Doctoral Dissertations

Carbon dioxide (CO₂) injection into subsea or low-temperature water zones has emerged as a promising strategy for long-term, non-leaking CO₂ storage through the formation of solid hydrates. This research investigates CO₂ injection into Berea sandstone cores saturated with water under simulated subsea conditions, focusing on hydrate formation behavior across varying temperatures, pressures, and injection flow rates. Experimental results demonstrate that CO₂ hydrate formation under dynamic (flowing) conditions occurs at significantly higher pressure compared to static conditions reported previously. At temperatures ranging from 0 °C to 5 °C, dynamic hydrate formation pressures were observed to be approximately double. This can be …

Strang-Type Exponential Integrators For Stiff Reaction-Diffusion Systems, Saburi Tolulope Rasheed

Doctoral Dissertations

Reaction-diffusion systems, as examples of semilinear parabolic partial differential equations, have played significant roles in the mathematical modeling of physical, chemical, and biological processes. Several reaction-diffusion systems typically do not have exact solutions in closed form, and numerically solving them also comes with challenges due to the presence of the nonlinear local interaction/chemical reaction dynamics representing the reaction term, coupling between components, multidimensionality of the diffusion operator, and stiffness of the diffusion and/or reaction terms. Wederive and analyze several second-order accurate exponential integrators of the Strang type for the time discretization of stiff reaction-diffusion systems. We utilize the finite difference …

The Interplay Of Seasonality, Evolution, And Density-Dependence In Discrete-Time Predator-Prey Dynamics, Narendra Pant

Doctoral Dissertations

We extend the discrete-time mathematical models developed in (Ackleh et al., 2019) and (Ackleh et al., 2024) to account for seasonal prey reproduction and build a class of discrete-time predator-prey seasonal models. Each model distinguishes between breeding and non-breeding seasons, representing prey reproduction as a periodic function of period 2. Altogether, three different models are analyzed. In the first part, we extend the predator-prey model from (Ackleh et al., 2019) to incorporate seasonality. We study the resulting dynamics and show that when the inherent reproduction number of the prey and the invasion reproduction number of the predator are larger than …

Building And Restoring Trust In Deep Learning: From Multimodal Sensing To Generative Synthesis And Model Integrity, Liqun Shan

Doctoral Dissertations

Deep learning has become a foundational technology for modern intelligent systems used in sensing, authentication, media generation, and automated decision-making. As these systems are increasingly deployed in security- and privacy-sensitive settings, ensuring their trustworthiness has become a critical challenge. Yet deep learning models remain vulnerable to spoofed sensory inputs, synthetic media, and malicious behaviors hidden within trained networks. These vulnerabilities undermine reliability and raise serious concerns about whether such systems can be trusted under adversarial and deceptive scenarios. This dissertation investigates how to build and restore trust in deep learning across three tightly connected dimensions: multimodal sensing, generative authenticity, and …

A Qualitative Study Examining Teachers' Knowledge And Awareness In Recognizing The Characteristics Of Twice Exceptional Learners: An Underrepresented And Underserved Population, Adrianne Monique Williams

Doctoral Dissertations

Over the past 30 years, research on twice exceptional learners has been gradually increasing, however, knowledge and awareness of the information in the educational community have been slowly evolving (Bailey & Rose, 2011; Baum, 2004). Outwardly, twice exceptional students may present as typical. Still, they face many unique challenges that include academic achievement, social awkwardness, executive functioning deficits, social communication challenges, and teachers who are not aware and trained to meet the atypical needs of these students. Researchers and practitioners are becoming increasingly aware of the underrepresentation that plagues gifted and talented programs, especially concerning twice exceptional students, and students …

Diversity, Systematics, And Phylogenomics Of The Neotropical Glass And Longtail Knifefishes (Gymnotiformes: Sternopygidae), Kevin Thomas Torgersen

Doctoral Dissertations

This dissertation provides a comprehensive systematic and phylogenetic study of the electric knifefish family Sternopygidae, integrating morphological, molecular, osteological, and phylogenomic data to clarify species diversity, evolutionary relationships, and biogeographic patterns in this Neotropical group. Across six studies, the work reveals that Sternopygidae diversity has been significantly underestimated due to morphological conservatism that obscures species boundaries. Chapter 1 revises the genus Sternopygus in the Guiana Shield, identifying nine species (five new) using osteology, morphometrics, and µCT imaging. Distinct anatomical traits and distribution patterns show strong regional structuring, highlighting the Guiana Shield as a diversification center. Chapter 2 describes a new …

Multidomain Modeling And Ramp-Aware Forecasting Of Floating Photovoltaic Systems For Water-Energy Nexus Applications, Md Atiqur Rahaman

Doctoral Dissertations

Floating photovoltaic (FPV) systems have become a transformative renewable energy technology because of their cooling effects on PV performance and ability to prevent water evaporation in land-constrained areas. Although FPV systems have the potential to become a commercially viable technology, their large-scale deployment remains constrained by uncertainties in thermal behavior, sustainability, and grid-operational variability. This dissertation identifies and characterizes these three key issues and presents an integrated, measurement-based evaluation of a 130 kW FPV installation located at the Passaúna reservoir in Brazil. In the first contribution, four temperature models, including physical and empirical models, were developed and comparatively evaluated to …

The Promise And The Punishment: A Critical Analysis Of Pbis At The Intersection Of State Discipline Policies In Louisiana, Ashley D. Willis-Brooks

Doctoral Dissertations

Positive Behavioral Interventions and Supports (PBIS) emerged as a preventative instructional alternative to exclusionary and punitive school discipline practices emphasizing tiered systems of support, data-based decision making, and proactive behavioral instruction. Despite its strong theoretical foundation and widespread adoption, PBIS implementation has produced uneven outcomes, particularly in policy contexts where state discipline statutes continue to authorize exclusionary practices. In Louisiana, PBIS is promoted through state guidance as an evidence-based framework; however, governing discipline policies simultaneously permit suspension, expulsion, and zero-tolerance provisions. This coexistence raises critical questions regarding alignment, coherence, and equity within the state’s discipline system. The purpose of this …

Learning And Predicting The Performance Of Gradual Type System, Mohammad Wahiduzzaman Khan

Doctoral Dissertations

Gradual typing reconciles the complementary strengths of static and dynamic typing by allowing programmers to incrementally introduce type annotations while preserving the flexibility of dynamically typed code. This approach improves reliability, documentation, and tooling support without sacrificing rapid prototyping. To ensure soundness, gradual type systems enforce annotations through runtime checks, typically implemented via cast insertion. Although these checks guarantee correctness, they can introduce substantial and highly variable runtime overhead, making performance prediction and optimization a central challenge for practical adoption. Prior work has largely focused on coarse-grained (macro-level) configurations, where entire modules are either fully typed or untyped. While such …

Fashioning The Self: Trauma, Disability, And Autofiction In Contemporary Quebecois Literature, John Ashburn

Doctoral Dissertations

This dissertation brings into dialogue trauma studies, disability studies, queer theory, and scholarship on autofiction and self-portraiture to examine representations of the self in contemporary Quebecois literature. Focusing on La fille d’elle-même (2021) by Gabrielle Boulianne-Tremblay, Tu aimeras ce que tu as tué (2017) by Kev Lambert, Grosse (2018) by Lynda Dion, Désormais, ma demeure (2020) by Nicholas Dawson, Chienne (2019) by Marie-Pier Lafontaine, and Ouvrir son cœur (2018) by Alexie Morin, this study argues that the literary self emerges as fundamentally unstable, shaped by trauma, embodiment, cognitive variation, and shifting configurations of gender and sexuality. Across this corpus, fragmentation …

Challenges In Tracking Methane Seepage Variability: The Δ13c Proxy Through Individual Benthic Foraminifera Analysis, Gracie Babineaux

Doctoral Dissertations

Methane seeps are dynamic biogeochemical systems that influence carbon cycling, seafloor ecology, and gas hydrate stability along continental margins. Yet reconstructing past methane seepage remains challenging because most sedimentary proxies integrate over long timescales and cannot resolve the short-lived or spatially restricted methane pulses that characterize many seep environments. This dissertation evaluates the reliability, sensitivity, and limitations of benthic foraminiferal δ¹³C as a proxy for methane-rich porewater conditions across two contrasting seep systems: long-term seepage at Woolsey Mound in the northern Gulf of Mexico and short-term, spatially variable seepage along the Chilean Margin. Using Individual Foraminifera Analysis (IFA), scanning electron …

Investigating The Distribution And Origin Of Pitted Mounds On Mars Using Machine Learning-Based Mapping And Integrated Geological Analysis: Application To Isidis Planitia, Precious Batubo

Doctoral Dissertations

Pitted mounds are widespread landforms across the northern plains of Mars, yet their origin remains uncertain. These features have been interpreted as possible expressions of subsurface fluid activity, including sedimentary volcanism, magmatic processes, or other fluid-assisted mechanisms. Determining their distribution, morphology, and geology is therefore important for understanding the evolution of subsurface hydrological processes and the planet’s potential for habitability. However, the large spatial extent of mound-bearing terrains makes comprehensive manual mapping impractical. This dissertation presents an automated approach to mound detection using Faster Region-Based Convolutional Neural Network (Faster R-CNN) from high-resolution Context Camera (CTX) images including morphometric and mineralogical …

Enhancing Hiv Prevention: Implementation And Evaluation Of A Standardized Hiv Risk Assessment Screening In A Primary Care Setting, William Duckworth

Doctoral Dissertations

Background: HIV remains a persistent public health concern, with 1.3 million people affected worldwide. Although advances in treatment have improved long-term management, early prevention still relies on identifying individuals at elevated risk. In many primary care settings, routine HIV risk assessment is inconsistent or absent, resulting in missed opportunities to screen, educate and initiate prevention strategies such as pre-exposure prophylaxis (PrEP). This gap underscores the need for structured, evidence-based tools to improve early risk identification and strengthen HIV prevention efforts. Purpose: Implement and evaluate an evidence-based standardized screening process for HIV risk assessment to achieve early identification and enhance appropriate …

Development Of Artificial Intelligence Based Geophysical Technique For Unconventional Resource Exploration, S M Shamsul Hoque

Doctoral Dissertations

Unconventional shale resources have become an important source of oil and gas in the United States, but their characterization remains challenging because of strong heterogeneity and complex elastic and geomechanical behavior. Important properties, such as total organic carbon (TOC) and brittleness, play a key role in evaluating source quality, reservoir behavior, development potential, and subsurface storage suitability. This dissertation develops artificial intelligence-based geophysical techniques to improve unconventional resource exploration and characterization by integrating seismic attributes, well-log data, deep learning, multicomponent seismic registration, and joint PP-PS inversion. A TOC estimation technique is developed and applied to both the Tuscaloosa Marine Shale …

Optimizing Well-Being In Post-Stroke Aphasia: Improving Access And Participation In Mental Health Care, Ashley H. Kidd

Doctoral Dissertations

This dissertation is focused on improving the well-being of people with aphasia. The overall aim of this research agenda is to move the healthcare system forward in its understanding of managing people with aphasia’s well-being after diagnosis. This focus is addressed through a compilation of three separate academic articles that are published or submitted to journals for the peer review process in speech-language pathology. All three works are focused on aphasia, a language disorder resulting from acquired brain injury, and the well-being of the person with aphasia. The first article focuses on managing the communication breakdowns that occur during group …

Clinician Perspectives On Fistula Mental Health, Victoria K. Leonard

Doctoral Dissertations

Background – Obstetric fistula is a childbirth injury caused by prolonged labor that leads to stillbirth and incontinence, spurring social exclusion and isolation. These layers of trauma put women with fistula at great risk for psychological suffering, which has profound negative socioeconomic impacts on them, their families, and communities. This study captured treatment as usual at Comprehensive Community Based Rehabilitation in Tanzania (CCBRT), the country’s largest provider of fistula care.

Method – Improving holistic fistula treatment requires engaging the clinicians who care for women with fistula. This study aimed to investigate the training, beliefs, and treatment approaches of nurses and …

Cultivating Healing: Understanding Pinay Adolescent Social And Emotional Well-Being, Dylan R. Francisco

Doctoral Dissertations

The Filipina/x/o American community is the third largest Asian American ethnic community in the United States (U.S. Department of Commerce, 2023). Among the population, adolescents in particular have been identified as being in a pivotal period, as adolescence in the Asian American community marks the unfolding of identity development, in addition to increasing familial and societal pressures (Choi et al., 2018).  Existing research has identified Filipina/x/o American adolescents in particular to have higher rates of smoking, alcohol use, teen births, depressive rates, and thoughts about suicide. Despite these growing concerns, limited studies have been conducted on this specific ethnic community …

Exploring The Use Of Nondigital And Digital Games In The Classroom Of Teaching Chinese As A Foreign Language For Adult Learners, Zheng George

Doctoral Dissertations

Game-based learning (GBL) has gained increasing attention as an instructional strategy in foreign language education due to its potential to enhance motivation, engagement, and language acquisition. However, most existing research has focused on young learners or on languages other than Chinese, leaving a gap in understanding of how games are used to teach Chinese as a Foreign Language (CFL) to adult learners. In addition, prior studies have primarily examined learners’ perspectives, with limited attention to teachers’ instructional practices when implementing game-based instruction. The purpose of this mixed-methods study was to explore how CFL teachers integrate nondigital and digital games in …

Identifying Social Disparities Inside The Colombian Jesuit Schools From The Students’ Perceptions, Fr. Edwin Mauricio Martínez Callejas Sj

Doctoral Dissertations

This thesis conducts a comprehensive investigation into social disparities within Colombian Jesuit schools through the voices and perceptions of their students. Employing a Critical Pedagogy framework inspired by Paulo Freire, the research centers on understanding how students from three Jesuit schools in major Colombian cities—Medellín (Colegio San Ignacio), Bucaramanga (Colegio San Pedro Claver), and Barranquilla (Colegio San José)—perceive and navigate issues of social inclusion, ethnic diversity, gender equality, socioeconomic status, political polarization, and religious plurality. The study utilizes qualitative methods, including focus groups and interviews with students, teachers, staff, and parents, to explore school convivencia (coexistence and social harmony) and …