Digital Commons Network^™

Initial Evaluation Of Hydrogen/Deuterium Exchange-Mass Spectrometry For Filtering Isobaric Candidate Structures Of Metabolites, Olufemi Farotimi

Theses and Dissertations

Mass spectrometry-based metabolomics is a common analytical tool used to identify metabolites. Identifying specific metabolite structures associated with liquid chromatography tandem mass spectrometry (LC-MS/MS) features remain analytically challenging. Complete hydrogen-deuterium exchange (HDX) is hypothesized to be complementary to retention time and fragmentation patterns for narrowing down the number of potential candidate structures for a given precursor m/z. In this work, the hypothetical number of exchangeable protons was assigned to an array of subsets of the Human Metabolome Database (HMDB), based on known exchange behavior obtained from literature. Six model compounds (for which experimental data were also collected, four additional model …

The Role Of The Triassic-Early Jurassic Eagle Mills Formation In The Development Of Smackover Lithium-Rich Brines, Timothy J. Palmer

Theses and Dissertations

Lithium‑rich brines of the Upper Jurassic Smackover Formation represent a major domestic critical‑mineral resource, with USGS estimates of 5.1–19.0 million tonnes of Li in Arkansas. Although Li enrichment occurs only in high‑TDS brines, elevated salinity alone cannot generate the observed Li concentrations; Li must be supplied through water–rock interaction with phyllosilicates. This dissertation evaluates the Triassic–Early Jurassic Eagle Mills Formation as the primary basin‑scale Li source using whole‑rock geochemistry, XRPD mineralogy, petrography, laser‑ablation ICP‑MS, and Li‑isotope analyses of produced brines. The Eagle Mills Formation is thick, made of proximal, mid, and distal fan deposits that include fluvial channel sands, floodplain …

Scale Dependent Microbial Assembly In A Dendritic River Network, Tyler M. Redman

Theses and Dissertations

River networks organize ecological communities across spatial scales, but whether bacterial communities follow these patterns remains poorly understood. This thesis examined microbial community assembly across three nested spatial scales in a dendritic watershed in east-central Mississippi (USA), asking whether dispersal or environmental selection governs community composition at each scale. At the watershed scale, bacterial diversity increased from headwaters to the river mainstem, consistent with longitudinal diversity accumulation predicted by the River Continuum Concept. At the confluence scale, the composition of post-confluence communities can be predicted as simple mixtures of their tributary inputs, supporting that conservative mixing dominates when unique communities …

Microcystin-Lr And Anatoxin-A Effect On Channel Catfish (Ictalurus Punctatus) Immune Cell Function And Susceptibility To Microbial Pathogens (Aeromonas Hydrophila And Edwardsiella Piscicida), Treva Billyard

Theses and Dissertations

Harmful algal blooms are increasing in frequency worldwide, resulting in greater exposure of aquatic organisms to cyanobacterial toxins that threaten fish health and freshwater ecosystems. Although microcystin-LR (MC-LR) and anatoxin-a are well known for their hepatotoxic and neurotoxic effects, respectively, their broader impacts on immune function, cellular metabolism, and host-pathogen interactions remain poorly understood. The objective of this dissertation was to investigate the immunotoxic, metabolic, and molecular effects of MC-LR and anatoxin-a in channel catfish (Ictalurus punctatus) while evaluating the influence of MC-LR on the growth of important bacterial fish pathogens. Channel catfish were exposed to MC-LR or anatoxin-a, and …

A Comprehensive Approach To Cognitive Offloading, Oscar Daniel Ramirez Perez

Theses and Dissertations

Learners use a variety of strategies to engage with real-world learning material. One such strategy is cognitive offloading: the reliance on external stores to alleviate internal cognitive demand. Past research has found that learners remember less when they study with the expectation of access to an external store during a subsequent test relative to when they study without that expectation. One proposed theory is the study effort hypothesis: when learners expect access to an external store, they reduce their encoding effort based on the belief that their internal memory of the information will be less important when they have access …

Staffing Reductions, Visitor Sentiment, And Recreation Demand In U.S. National Parks, Rebekkah Adicoff

Theses and Dissertations

Staffing changes in U.S. national parks have the potential to influence both visitor experience and recreation demand. This study examines how an abrupt system-wide staffing reduction affected visitor sentiment and visitation across the National Park System, while accounting for differences in park-level risk exposure. Using the February 2025 staffing reduction as a quasi-natural experiment, the analysis combines monthly park-level visitation data with TripAdvisor visitor reviews from January 2024 to August 2025. Sentiment scores derived from reviews measure perceived experience quality, while recreation demand is modeled using fixed-effects count models (Poisson and negative binomial) that control for seasonality and park characteristics. …

Family Religious Socialization Index: Development And Preliminary Validation, Kaelie Rene Crockett

Theses and Dissertations

A key area of interest for religious scholars is how religious beliefs are passed across generations, or religious socialization. To expand this field of study, a theoretically grounded, validated measure of this construct is needed. This article describes the development and validation of the Family Religious Socialization Index (FRSI), a multi-informant, multidimensional assessment of the processes through which parents socialize religion and faith in their children. Based on Social Cognitive Theory and through a rigorous development and validation process, three subscales were developed to represent the primary processes of religious socialization. The FRSI consists of two parallel scales, a parent …

Identifying The Brain Circuits Involved In Religious Obsessive-Compulsive Disorder, Kiana Bunnell

Theses and Dissertations

Obsessive-compulsive disorder (OCD) is an often-debilitating psychiatric disorder involving a pattern of obsessive thoughts and compensatory compulsions. Symptoms tend to be chronic, leading to substantial emotional burden and significant impairment across multiple domains of daily functioning. Previous research has identified some consistency in the brain regions implicated in OCD. In particular, cortico-striato-thalamo-cortical (CSTC) circuitry has been linked to behavioral features commonly observed in OCD. Moreover, some studies suggest that distinct patterns of brain activation and functional connectivity may be associated with different OCD symptom dimensions, though findings have not been consistent. One symptom dimension of OCD (scrupulosity) is characterized by …

Is “No Change” Really No Change?: A Qualitative Analysis Of Clients With “No Change” On Routine Outcome Monitoring Who Report Improving In Therapy, Audrey Louise Stewart Parker

Theses and Dissertations

Routine outcome monitoring (ROM), the practice of tracking client progress in therapy by administering regular questionnaires to assess functioning, has demonstrated a significant positive effect on psychotherapy outcomes, especially for clients are who not improving as expected. However, some researchers argue the symptom-based measures and outcome classification criteria commonly used in ROM may not represent a complete picture of client change. A recent body of mixed-methods research has investigated these ROM-determined outcome categories to gain insight into client experiences and whether the category and client perception of therapy outcome align. In this investigation, researchers have found significant variety within outcome …

Modifying Lta Zeolites For Reversible Hydrogen Sulfide Capture And Elucidating The Structure Of The Incorporated Metal And Sulfur Ions, Adeyemi D. Ojaide

Theses and Dissertations

Hydrogen sulfide (H2S) is a highly toxic and corrosive gas that poses significant environmental and industrial challenges, particularly within the wastewater treatment and oil and gas sectors. H2S leakage is among the deadliest industrial hazards, highlighting the urgent need for the development of highly efficient, non-corrosive adsorbents. This dissertation provides an in-depth examination of the use of metal-zeolites for H2S capture. We carefully investigate the impact of multiple divalent and one monovalent transition metals on LTA zeolites to optimize H2S removal. While Linde Type A (LTA) zeolites offer a robust structural framework for gas separation, a comprehensive understanding of how …

Intensification Of Thermal Energy Storage Systems Based On Sodium Nitrate, Hari Suthan V Mr

Theses and Dissertations

Thermal energy storage (TES) systems employing phase change materials (PCM) bridge the gap between thermal energy demand and supply. The low thermal conductivity of sodium nitrate (NaNO3), an inorganic PCM for high-temperature TES systems restricts charging and discharging kinetics, reducing system-level performance. This thesis investigates the intensification of sodium nitrate-based thermal energy storage systems through the incorporation of different classes of additives. Metal oxides (zinc oxide and aluminium oxide) and carbon-based materials (graphene oxide (GO) and expanded graphite (EG)), were incorporated into NaNO3 to improve its thermophysical properties (thermal conductivity, latent heat, specific heat).

Composites were prepared using low-energy ball …

Behavioral Effects Of Novel Treatments For Pain Management Using Combinatorial Methods, Rohit Rajeev Nambiar

Theses and Dissertations

Pain, despite being an uncomfortable feeling to experience, is a necessary protective mechanism for the body1. Understanding that pain results from several different mechanisms within the body is important to discovering the optimal way to treat and manage a person’s pain. Modern medicine has seen numerous advancements in treating or managing acute and chronic pain, particularly with opioid drugs. However, these treatments come with potential side effects, including opioid use disorder (OUD) and fatal overdose. Finding new treatment methods, or improving existing methods, is crucial for patients with pain. This thesis explores two projects looking to develop safer analgesia using …

Threads Across The Atlantic: A Dialogue Of Feminist Writings Between Portugal And Cape Verde, Elliana Shillig Venancio

Theses and Dissertations

This thesis examines the feminist literary traditions of Portugal and Cape Verde through a comparative analysis of Ana de Castro Osório’s Infelizes and Dina Salústio’s Mornas eram as noites. Separated by nearly nine decades and an ocean, these two works nonetheless converge in their insistence on women’s autonomy, bodily sovereignty, and resistance to patriarchal structures. Drawing on Hélène Cixous’s theory of écriture féminine and Kimberlé Crenshaw’s framework of intersectionality, this thesis argues that despite the significant differences in time, geography, and socio-political context that separate these authors, powerful threads of feminist consciousness bind their writing together. At the same time, …

Automated Classification, Measurement, And Semantic Segmentation Of Open-Web Joists From Point Cloud Data, Justin Raymond Dworacek

Theses and Dissertations

This thesis presents a BIM-oriented methodology for the automated classification, measurement, and segmentation of structural trusses from point cloud data. A real truss point cloud and a complementary synthetic dataset derived from CADBIM Revit families were used to develop and evaluate the workflow. Classification was performed using a rule-based Python algorithm based on principal component analysis, side-view feature extraction, and family-specific geometric decision logic, while a separate family-aware script was used to extract key truss dimensions. Semantic segmentation was evaluated using a PointTransformerV3 model to separate truss and non-truss points in mixed point cloud scenes. The results demonstrated strong performance …

A Graphical Approach To Isospectral Unfoldings, Dallin Seyfried

Theses and Dissertations

Isospectral reductions are mathematical techniques used to shrink a matrix, or a graph, into a smaller, dimensionally reduced form while preserving its spectrum. Simple graphs that share isospectral reductions also share quantum walk properties. As such we further develop the inverse process, isospectral unfoldings, to find graphs that share isospectral reductions. We first prove many conditions relating to isospectral reductions and unfoldings. Afterwards, we define two new unfolding processes: general unfolding which unfolds the graph one vertex at a time, and equitable partition unfolding which excels at larger graph unfolding. In particular, through equitable partition unfolding, we discover many graphs …

Surface-Modified Zinc Oxide Nanostructures For Ammonia Detection, Gowri Shonali N Ms

Theses and Dissertations

The escalating demand for sustainable gas sensors with low-ppm detection has driven research on surface-engineered nanomaterials for portable air-quality and health screening. This thesis focuses on the fabrication of nanostructured ZnO films as chemiresistive sensors for NH3 detection at RT. This study investigates surface modification using GO, rGO, g-C3N4, Ti3C2Tx; (Se, and Te) ink using a drop casting technique over DC-sputtered ZnO films. Surface modification plays a vital role by providing plenty of active sites, enhancing defective oxygen vacancy, facilitating charge transfer, and synergistic interaction between adsorbed oxygen species to enhance the sensing performance at RT. Among them trGO/ZnO hybrid …

Learning, Abstraction, And Creative Search For Interactive Agents, Jonathan Demke

Theses and Dissertations

Artificial intelligence systems are increasingly deployed as autonomous agents that interact directly with complex environments. Ensuring these agents remain reliable, adaptable, and useful presents an ongoing practical challenge. This dissertation studies agent-environment interactions through a progressive lens, examining behavior from foundational training stability and abstraction discovery to adaptation in unpredictable settings and open-ended creative search. The investigation begins by analyzing how hyperparameter settings affect early-stage Deep Q-Network performance, yielding practical guidelines for debugging reinforcement learning implementations. To address the challenge of long-horizon planning, the discovery of temporally extended options is formalized as the Minimum Shortcut Problem, demonstrating how agents can …

A Coupled Reaction-Diffusion Model Of Promoting And Suppressing Interactions Among Cancer Hallmarks In Endometrial Cancer, Jeddy Bennett

Theses and Dissertations

Spatial transcriptomics enables the scoring of Cancer Hallmarks at a high resolution across a tissue biopsy, yet current analyses of these data remain largely descriptive, treating each spot as a static, independent observation. This thesis develops a coupled system of advection-diffusion-reaction partial differential equations to model the hallmark landscape as the steady-state solution of an underlying spatial process, and casts the recovery of its physical parameters as a PDE-constrained inverse problem. The framework is implemented in FEniCSx on tissue-specific finite element meshes derived from two endometrial cancer biopsies provided by the Huntsman Cancer Institute, with subdomains, boundary interfaces, and an …

Sand Distribution On Titan And Implications For Sand Transport And Interconnectedness Of Sand Seas, Delaney Rose

Theses and Dissertations

The vast equatorial sand seas of Saturn's moon Titan are of particular interest for understanding surface processes and the budget of organic materials on Titan's surface. Previous studies have described sand dune morphology, transport, collection, and distribution patterns utilizing Cassini Imaging Science Subsystem (ISS), Visual and Infrared Mapping Spectrometer (VIMS), and Synthetic Aperture Radar (SAR) imagery. Studies have also shown evidence both for and against a global interconnected system of sand transport between Titan's major sand seas. This study worked both to create a higher resolution dataset of sand distribution using trimodal thresholding techniques applied to SAR images, as well …

Media Emotion Regulation And Executive Function In Childhood: Associations With Respiratory Sinus Arrhythmia, Lara M. Almeida

Theses and Dissertations

Media emotion regulation (MER), or the use of media to help children manage emotions, may influence children's development by shaping opportunities for practicing self-regulatory skills. Guided by the Dynamic, Relational, Ecological Approach to Media Effects Research (DREAMER) model, this study examined longitudinal associations between MER and executive functioning (EF) in early childhood and explored whether respiratory sinus arrhythmia (RSA), a physiological index of regulation, predicted developmental changes. Participants included 175 parent-child dyads assessed across two annual waves when children were approximately 4 and 5 years old. Structural equation modeling was used to test bidirectional associations between MER and EF while …

Physical Activity, Trauma, And Posttraumatic Stress: The Indirect Role Of Exercise Addiction, Anastasiia Rozumna

Theses and Dissertations

Exercise is often conceptualized as a protective factor for mental health, including for individuals exposed to trauma. However, less is known about whether exercise may relate to posttraumatic stress symptoms differently when it is accompanied by compulsive or addictive features. The present study examined whether volume and intensity of physical activity were associated with posttraumatic stress symptom severity indirectly through exercise addiction symptoms. This secondary cross-sectional analysis included 557 adults living in the United States who reported regular participation in sport or physical activity. Participants completed self-report measures of physical activity behavior, exercise addiction symptoms, trauma exposure, and posttraumatic stress …

A Systematic Review Of Posttraumatic Stress Disorder Among Hispanic Immigrants In The United States, Rashel Acireale

Theses and Dissertations

This study systematically reviews the literature on posttraumatic stress disorder (PTSD) among Hispanic immigrants in the United States, a population exposed to cumulative trauma across the migration process. Stressors may occur before, during, and after migration and include violence, family separation, dangerous travel conditions, discrimination, and fear of deportation. Despite these risks, findings on PTSD prevalence remain mixed, and Hispanic immigrants are underrepresented in clinical research and culturally informed interventions. This review examines sample representation, types and timing of trauma, PTSD measurement approaches, and the inclusion of cultural and contextual factors such as acculturation and immigration-related stress. It also evaluates …

College Sports Clubs: Engines Of Emotional And Social Development, Robert Robinson

Theses and Dissertations

This thesis examines the relationship between structured campus involvement and the development of campus connectedness among students at Rowan University. While the transition to university life is a critical period marked by social, emotional, and academic adjustments, this study highlights how sport clubs serve as a primary social anchor to facilitate successful integration. Utilizing a qualitative thematic analysis of focus group data across diverse campus organizations, this research clarifies how these spaces foster identity formation and resilience. Findings reveal that participation in sport clubs significantly enhances student wellbeing by providing support networks that mitigate early feelings of isolation. A key …

Depictions Of Girls With Adhd In Contemporary Picturebooks: A Critical Content Analysis, Madison Briann Smith

Theses and Dissertations

This study examines how girls with ADHD are depicted in contemporary picturebooks through the theoretical framework of critical disability studies (CDS). While research has increasingly explored disability representation in children's literature, depictions of girls with ADHD remain underexamined despite the ways in which ADHD manifests in female populations and the historical underdiagnosis of females with the condition. Using critical content analysis (CCA), six contemporary picturebooks featuring female protagonists with ADHD were analyzed for their visual and textual representations of neurodiversity. Findings were organized into two overarching themes: strength-based and deficit-based depictions. Strength-based portrayals emphasized creativity, identity formation through adult mentors, …

Properties Of Enjoyable Mathematical Contexts From The Student Perspective, Emilie Nadine Hendrickson

Theses and Dissertations

Researchers continue to grapple with how to meaningfully engage students in mathematical content. Many students report disengagement due to perceptions that mathematics is difficult, irrelevant, boring, or anxiety-inducing. This study sought to understand how students interpret and respond to different mathematical problem contexts, with particular attention to the reasons students describe certain problems as enjoyable or unenjoyable. Using semi-structured interviews, this research examined student responses to a variety of mathematical problem types primarily across affective engagement. Students reflected on specific problem contexts and explained which features supported or hindered their enjoyment and engagement. Students described that contexts were enjoyable have …

Comparing Principal Component Analysis And Sequential Fusion Deeponet With Varying Dataset Size For Design Space Exploration Of Hypersonic Flow, J. Dallan Trentman

Theses and Dissertations

Design space exploration and optimization of hypersonic vehicles is costly due to the difficulty of producing high fidelity CFD simulations in the hypersonic domain. Reduced order modeling can allow for design optimization at a fraction of the computational cost. This paper investigates the amount of training data required to produce an accurate Reduced Order Model. A PCA based ROM is developed and compared to a Sequential Fusion DeepONet by comparing model prediction accuracy, training time, and prediction time, across dataset sizes from 25 samples to 1024 samples. These models are applied to 2D hypersonic CFD simulations of the Orion reentry …

Resonant Shock Plate Simulation And Prediction Using Modal Substructuring, Harrison C. Denning

Theses and Dissertations

Aerospace structures such as rockets can experience various shock events during flight, such as stage separation or impacts. These shock events can expose components inside the rocket to large accelerations and stresses which in turn can damage the parts. Shocks are often simulated in the lab using a resonant shock plate test. Resonant shock plate testing is often used to qualify aerospace parts, as it can mimic the shocks experienced during launch and stage separations. However, during the course of development, both the definition of the shock environment and the design of the subcomponent tend to change, so that multiple …

Rfsoc Based Ground Penetrating Radar For Detection And Avoidance Of Underground Utilities, Brady Bowerbank

Theses and Dissertations

Preexisting underground utilities present a considerable danger to underground boring projects. Gas and electrical lines can be damaged, leading to major economic impact and even loss of life. While maps of underground utilities exist, they are not always accurate and gas and electrical lines can shift over time, necessitating tools to accurately detect utilities so that crews can steer the machines away from any possible danger. In this thesis, the design of a new frequency-modulated continuous-wave (FMCW) ground penetrating radar (GPR) is outlined. The design of a lightweight, flexible radar is demonstrated using the CASPER FPGA framework with an operating …

Isoperimetric Soft Robots, Mihai Stanciu

Theses and Dissertations

This thesis presents two advances in isoperimetric soft robotic trusses that improve their performance, modularity, and configurability. The first contribution introduces a large-scale modular robotic truss designed as a lightweight, reconfigurable structure for lunar applications. The system consists of inflatable fabric tubes routed through motorized roller units and interconnected by a newly developed spherical joint that enables multiple robotic triangles to connect at a common vertex. The resulting truss can be assembled into structures beyond a single octahedron while retaining compact stowage when deflated and untethered operation after initial inflation. Experimental validation demonstrates modular assembly, long-term pressure retention, load-bearing capabilities …

Recognition Of Autism Characteristics In Females: An Examination Of Stakeholders, Laurel Lyn Bishop

Theses and Dissertations

Autism is a neurodevelopmental communication disorder, characterized by differences in social communication, attention, interests, and sensory perception. Diagnostic criteria have historically applied to males, but clinical diagnostic criteria beginning in 2022 now include slight differences in traits comprising the female phenotype. Until recently, autistic females may be missed by the professional and education community or diagnosed later than males. Like their autistic male counterparts, they face an increased risk of suicidal ideation, but they also face more difficulties in peer relationships, academic problems, and increased anxiety and depressive symptoms, but may not get supports. School-age girls spend their days with …