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Molecular Dynamics Simulations Of Biologically Relevant Interfaces: From Tear Film Lipid Layers To Rna Adsorption On Silica Surfaces., Mahbuba Khanom

Electronic Theses and Dissertations

Molecular dynamics (MD) simulation is an important tool in biochemical sciences for studying complex molecular processes and interfacial interactions at the molecular level. Biological interfaces play key roles in processes such as ocular lubrication and biomolecular adsorption. This dissertation studies interfacial phenomena involving two distinct yet conceptually related systems: the tear film lipid layer (TFLL) at the air–water interface at the surface of the human eye, and RNA adsorption on silica surfaces. These studies provide insight into how interfacial composition, structure, and environmental conditions affect larger-scale behavior. Atomistic MD simulations were used to model the TFLL. The TFLL is essential …

“The Moment You Are Disabled; You Are Cut Off From Society.” Assessing The Experiences Of Disabled Ghanaians And The Rights Enshrined In The United Nations Convention On The Rights Of Persons With Disabilities (Crpd)., Solomon Sackey Amoatey

Electronic Theses and Dissertations

As Ghana continues to pursue inclusion and equality for disabled citizens, considerable tension remains between international human rights frameworks and local social, legal, and cultural practices. Guided by social constructionism and Critical Disability Theory (CDT), this qualitative, chapter-based study examined how disability is constructed through law, policy, and culture in Ghana. It also explored how these constructions influence the interpretation and implementation of disability rights. To achieve this, the study employed semi-structured interviews and document analysis to examine how law, policy, and cultural beliefs intersect to influence the implementation of the CRPD and lived experience of disabled Ghanaians.

Findings show …

Experiences Of Research Administrators With Faculty Researchers In Sponsored Project Compliance., Adrienne M. Lindsay

Electronic Theses and Dissertations

The purpose of this study was to examine how central office research administrators perceive and describe their professional interactions with faculty researchers, and how those relationships may impact compliance with sponsored project requirements in United States higher education institutions. Cohen et al.’s (1972) organized anarchy theory and Schein’s (2010) organizational culture theory provided a foundational context for understanding research systems within higher education institutions and the social environment in which research administrators navigate potentially contentious roles, both facilitating research and stewarding compliance for the institution and the sponsor. Findings emerged around specific challenges faced by research administrators, which included role …

Impacts Of Biology Modeling Pedagogy On Student Cogitive And Non-Cognitive Elements Of Learning., Jessie K. Newhouse

Electronic Theses and Dissertations

This dissertation employed a quasi-experimental design used to investigate the use of a modeling pedagogy in high school biology. Modeling is a key element of the Science and Engineering Practices of the Next Generation Science Standards. While research of Model Based Pedagogy (MBP) in physics and chemistry is well established, the influence on biology instruction remains less understood. This research examined how MBP affected both cognitive and non-cognitive components of student learning compared to traditional biology instruction. Existing data collected by Dr. Kathy Malone in collaboration with Ohio State University (2016) were analyzed to study the effectiveness of the MBP. …

Thermal And Non-Thermal Mass Transport Effects In Plasmon-Assisted Electrochemistry., Md Al Amin

Electronic Theses and Dissertations

Plasmon-assisted electrochemistry has received attention due to its effects of hot charge carriers, photothermal heating, and enhanced electromagnetic field impact on electrochemical transformation. These effects have contributed to lowering the onset potential and increasing the reaction kinetics. Numerous studies have been employed to differentiate the effect of photothermal heating from hot charge carriers on the electrochemical reaction. Most of these studies have been employed to measure and quantify the photothermal heating effects at equilibrium temperature; however, localized heating from the incident light does not result in homogeneous heating across the electrochemical cell. Many studies investigating the photothermal heating effect in …

A Persistent Homology Framework For Scrna-Seq: Assessing Clustering Robustness And Quantifying Preprocessing And Integration Effects On Topological Features., Jonah Daneshmand

Electronic Theses and Dissertations

As single-cell RNA sequencing (scRNA-seq) data expands, robust methods for integrating diverse datasets are critical. This dissertation applies Persistent Homology (PH), a technique from Topological Data Analysis (TDA), to a collection of scRNA-seq datasets spanning eight tissue types to quantify how data integration affects topological features and biological interpretability. We assessed global topological structure using Betti curves, Euler characteristics, and persistence landscapes across raw, normalized, and integrated data representations. Our analysis revealed a performance inversion: while conventional methods excelled on unintegrated data, high-granularity topological methods, particularly those sensitive to global data structure, became superior after integration. This suggests a synergy …

Controlling Selectivity In Electrocatalytic Co2 Reduction With An External Magnetic Field., Nawaraj Karki

Electronic Theses and Dissertations

My dissertation describes how to alter the speciation and concentration of molecules at the electrode-electrolyte interface, and how those alterations affect reactivity and selectivity. This dissertation presents two distinct approaches to control the mass transport of neutral molecules such as carbon dioxide (CO₂) at the electrode-electrolyte interface by using an external magnetic field. The first finding demonstrates that magnetic fields indirectly affect the mass transport of target analytes such as CO₂ molecules by selectively interacting with charged species, such as hydroxide ions (OH^-). Such interaction induces magnetohydrodynamic (MHD) effects, which generate localized hydrodynamic flow and …

Integration And Modulation Of Visual Signals In Dorsal Thalamus., James Whitley

Electronic Theses and Dissertations

The visual thalamus is influenced by a diverse array of cortical and subcortical inputs that shape how information is transmitted to cortex. Using a variety of anatomical, optogenetic, and in vitro physiological techniques I investigated the differential impacts of modulation and integration of first and higher-order thalamic nuclei, while relying on influential concepts on the general organization of thalamic nuclei. In the first data chapter, I determined how GABAergic pretectum (PT) projections to the dorsal lateral geniculate nucleus (dLGN) and visual thalamic reticular nucleus (vTRN) can influence retinogeniculate signal transfer. We found that the PT provides over 75% of the …

Risk And Protective Factors For Suicidal Thoughts And Behaviors For Black Adolescent Males With Exposure To Adverse Experiences Post-Covid 19 Pandemic: Findings From The 2023 National Youth Risk Behavior Survey., Amanda Minogue

Electronic Theses and Dissertations

Suicide is the second leading cause of death among adolescents aged 10-24 in the United States. In 2022, 784 Black adolescent males died by suicide. Recent studies have found that traditionally common associations of risk factors of suicidal thoughts and behaviors are not experienced by Black adolescents, challenging how to determine and detect risk. This dissertation reviewed the variables in the national Youth Risk Behavior Survey that closely align with risk and protective factors of suicidal thoughts and behaviors, and the interaction between these and adverse experiences in Black adolescent males. Results of this study found that among the 9 …

The Role Of Fast-Food Consumption, Residential Fast-Food Exposures, And Urinary Essential Trace Heavy Metals In Colorectal Cancer (Crc) Outcomes., Jeevan Adhikari

Electronic Theses and Dissertations

Background: Colorectal cancer (CRC) is a public health concern. Within the United States (US), fast-food consumption and environmental exposure to heavy metals have increased. The impact of fast-food consumption frequency from fast-food restaurants, residential fast-food exposures, and urinary essential trace heavy metals in relation to CRC outcomes have not yet been rigorously evaluated in the US. Methods: Within the LEAPS-CRC study, we used geographic information systems (GIS) and logistic regression to study the association of fast-food consumption, residential proximity to a fast-food outlet, and urinary essential trace metals with CRC incidence. Additionally, within Kentucky Cancer Registry (KCR) CRC cases, the …

Genetic Identification Of A Rapidly-Adapting Low-Threshold Mechanoreceptor Innervating Fungiform Papillae., Thomas Alexander Myers Ii

Electronic Theses and Dissertations

Mechanosensory innervation of the oral cavity enables us to detect the texture and location of the foods we consume. Our goal was to find a genetic identifier for a mechanoreceptive subtype. Toward this goal, we examined neurons expressing the neurotrophin receptor TrkC, parvalbumin (Pvalb), and the glutamate transporter Vglut3. Because different papilla types contribute to food detection in different ways, we examined the innervation patterns of these neuron subtypes. We found that Pvalb+ and Vglut3+ neurons were fungiform papilla specific, where TrkC innervated both papilla types. We examined the anatomy of the three genetic populations, finding that the Pvalb+ neurons …

Preparing Confident Elementary Mathematics Teachers: Addressing Anxiety, Building Fluency, And Strengthening Practice., Amber Diamond Pendleton

Electronic Theses and Dissertations

This dissertation, presented in three articles, examines how elementary preservice teachers (PSTs) experience and develop as mathematics learners and future educators when methods coursework deliberately integrates mathematical reasoning with affective supports. Collectively, the studies investigate how research-informed instructional design may help address mathematics anxiety (MA), mathematics teaching anxiety (MTA), procedural fluency, and instructional practice. The first article, written for practitioners and elementary mathematics teachers, illustrates how well-established instructional routines, such as number talks and student work analysis, can be facilitated to support procedural fluency in multiplication. Using classroom vignettes, this article highlights instructional moves that make structure visible, promote strategy …

Characterizing Hexavalent Chromium Neurotoxicity Across Laboratory Models., Samuel Thomas Vielee

Electronic Theses and Dissertations

Hexavalent chromium [Cr(VI)] is a ubiquitous environmental pollutant and potent toxicant. Exposure to Cr(VI) in drinking water is primarily associated with cancers, inflammation, and hepatotoxicity; however, recent studies have identified Cr(VI) as a neurotoxicant in rodent and cell culture models. The literature suggest chromium accumulates in the brain, induces widespread neurodegeneration, and alters rodent behaviors. Despite these data, we lack a detailed and consistent assessments of Cr(VI) neurotoxicity across models, and interactions between aging and Cr(VI) neurotoxicity are not reported in the literature. In this dissertation, we characterize Cr(VI) neurotoxicity across 3 laboratory models: Sprague-Dawley rats, Caenorhabditis elegans, and …

Exposure To Pm2.5 And Aging., Daniel Chris Gomes

Electronic Theses and Dissertations

Inhalation of fine airborne particulate matter (PM_2.5) is an environmental risk factor for numerous health disorders, including cardiovascular diseases (CVD). While several studies have shown that PM_2.5 exposure can induce oxidative stress, DNA damage, and inflammation, the underlying mechanisms that translate these effects into systemic pathology remain poorly understood. Some recent studies have shown that PM_2.5 exposure can lead to telomere shortening in leukocytes, but the generality of this outcome and contribution to endothelial dysfunction has not yet been fully explored. We hypothesized that PM_2.5inhalation accelerates cellular aging and senescence in both circulating peripheral …

Residential Segregation And Breast Cancer In Louisville: Impact Of Race And Contextual Factors On Advanced-Stage Diagnosis, Delayed Treatment, And Disease-Specific Mortality., Toheeb Ajani Mustapha

Electronic Theses and Dissertations

Female breast cancer (BC) remains the most commonly diagnosed non-skin cancer and the second leading cause of cancer death among U.S. women. Despite advances in detection and treatment, substantial inequities in BC outcomes persist, driven in part by structural forces such as residential segregation. This dissertation examined the relationship between residential segregation, BC outcomes, and key contextual factors in Louisville, Kentucky. Using data from the Kentucky Cancer Registry, American Community Survey, CDC’s Population-Level Analyses and Community Estimates, and the National Neighborhood Data Archive, the study tested two hypotheses: (1) higher Black/low-income segregation is associated with elevated risks of adverse BC …

Increasing Histidyl Dipeptides In Skeletal Muscle Preserves Muscle Mass And Function In Heart Failure., Mamata Hiraman Chaudhari

Electronic Theses and Dissertations

Introduction: Heart failure is a systemic disease associated with multiple comorbidities, such as skeletal muscle wasting and cardiopulmonary disease. Muscle wasting in heart failure patients is a severe comorbidity associated with decreased exercise capacity and poor quality of life. Previous reports show that oxidative stress is increased in the skeletal muscle of heart failure patients, which can directly lead to muscle wasting. However, antioxidant intervention in these patients was unable to improve cardiac function and consequently had no effect on muscle wasting. Although oxidative stress is the primary driver of skeletal muscle atrophy, no attempt has been made to examine …

A Multilevel Analysis To Evaluate Variability In Sdoh Clusters Within Rurality And Its Effects On Cancer-Specific And All-Cause Mortality In The Us., Stephie Ann Abraham

Electronic Theses and Dissertations

Social determinants of health (SDOH) factors have consistently been shown to impact all-cause and cancer-specific mortality. Area-level SDOH factors that coexist to form “high-risk” clusters are more prevalent in rural than urban areas. However, heterogeneity within rural and urban areas may contribute to variations in SDOH factors that could influence higher mortality rates and is not considered in other studies. The primary objective of this study was to utilize ecological and individual-level data to determine if the composition of SDOH clusters within counties in the rural-urban continuum contributes to differences in all-cause (AC) and cancer-specific mortality rates of lung and …

Perceived Organizational Support Of High-Performance Support Staff Members In Professional Soccer Organizations., Erica B. Thompson

Electronic Theses and Dissertations

The purpose of this study was to explore perceived organizational support among high-performance support staff (HPSS) within professional soccer organizations. Specifically, this study examined how HPSS define organizational support, identified factors that shape their perceptions, explored organizational challenges they experience, and analyzed how those challenges intersect with their perceptions of support. Organizational Support Theory (OST) and its central construct, Perceived Organizational Support (POS), served as the theoretical framework guiding this study. OST assumes employees form global beliefs about the extent to which their organization values their contributions and cares about their well-being. To address the study’s purpose, a basic interpretive …

Plasma-Enhanced Carbon Nanomaterial Synthesis: A Pathway To Reducing Greenhouse Gasses And Carbon-Based Waste., Zane Ronau

Electronic Theses and Dissertations

This research leveraged incorporation of capacitively coupled radio frequency plasma into chemical vapor deposition (CVD) for a reduction in the temperature requirements [a reduction of energy barrier] needed for the conversion of methane (CH₄), carbon dioxide (CO₂), and various carbon-based-waste to produce value-added carbon nanomaterials. An array of catalysts and catalyst supports were employed to optimize the synthesis of graphitic carbon under various gas environments, temperatures and pressures. The nanomaterials synthesized after fine tuning the growth parameters included graphene, carbon nanotubes (CNT), carbon microtubes and carbon nanocages with a variety of properties. Raman Spectroscopy was used …

Identifying Correlates Of Protection Of A Pneumonic Plague Vaccine., Caleb Samuel Whitley

Electronic Theses and Dissertations

Pneumonic plague is caused by inhalation of the bacterial pathogen Yersinia pestis. The immune response during Pneumonic plague occurs in two phases; an initial asymptomatic phase followed by a highly inflammatory and destructive phase resulting in 100% mortality if left untreated. The rapid onset of severe disease following the asymptomatic phase makes it difficult to administer antibiotics in time to prevent lethal outcomes. Therefore, the development of an effective vaccine is likely needed to combat pneumonic plague in areas of the world where Y. pestis remains endemic. One candidate subunit vaccine is protective in mice, a natural host for …

Orientation Or Disorientation? A Critical Content Analysis Of Refugee Cultural Orientation Curriculum., Amanda Jean Lacey

Electronic Theses and Dissertations

Cultural Orientation (CO) is a free, legally mandated, multi-session program intended to provide refugee newcomers ages 18-65 with the knowledge, skills, and attitudes needed to integrate and achieve self-sufficiency in the United States. Despite occurring at a critical time in the resettlement process, there has been almost zero scholarship analyzing the content or efficacy of domestic CO curriculum. This dissertation addresses that gap by performing a Critical Content Analysis (CCA) on The Road Ahead (TRA), the de facto official CO curriculum promoted through the Cultural Orientation Resource Exchange (CORE). Framed by a postcolonial perspective and informed by the …

Direct And Satellite-Based Quantification Of Greenhouse Gas Fluxes In Small Ponds., Mark Christopher Tierney

Electronic Theses and Dissertations

As evidenced by their historic losses due to anthropogenic activities, wetlands are undervalued ecosystems that provide numerous ecosystem services, from recreational opportunities to carbon (C) storage. However, these wetlands are also the largest natural source of atmospheric methane (CH₄). Additionally, small water bodies (< 10,000 m²) are disproportionately large emitters relative to larger lakes and reservoirs. As construction and restoration efforts proceed, it is crucial to identify wetlands that need restoration and to understand the factors driving both greenhouse gas (GHG) fluxes and the C balance of these systems. This dissertation investigates the drivers of greenhouse gas fluxes …

A Ralgef Inhibitor Suppresses Lung Cancer Stem Cell Development And Tumorigenesis., Raphael Ngozichi Suarez Jigo

Electronic Theses and Dissertations

The RALGEF family of proteins are direct downstream effectors of the RAS oncoprotein. RALGEFs act as guanine nucleotide exchange factors (GEFs) for downstream RAL proteins, thus tying RAS to the regulation of RAL. Genetic studies have demonstrated RAL proteins to be key drivers of RAS-driven transformation and metastasis. Furthermore, this pathway has been implicated in chemoresistance, exocyst-mediated transport, and the modulation of cancer stem cells. Previous work in our lab reported the activity of a novel pan-RALGEF inhibitor (C4-180) against RAS-driven pancreatic cancer models. Here we show the agent to be active against in vitro and in vivo models of …

A Comparision Of Teachers' Ratings Of Published Versus Ai-Generated Descriptions Of Evidence Based Practices In Education., Lora T. Hall

Electronic Theses and Dissertations

The persistent gap between educational research and classroom practice continues to limit teachers’ use of evidence-based practices (EBPs), despite strong empirical support and federal mandates encouraging their implementation. A key barrier to closing this research-to-practice gap is the limited accessibility, usability, and perceived relevance of traditional research dissemination formats. With the rapid rise of artificial intelligence (AI) tools capable of summarizing and restructuring complex information, this study examined whether AI-generated practitioner-oriented descriptions of an EBP would be rated differently from a published practitioner article on the same practice. Using an experimental cross-sectional survey design, 70 in-service teachers were randomly assigned …

An Exploration Of Factors Associated With Sport Fan's' Choice Of Ticketing Platforms., Jacob Owsley

Electronic Theses and Dissertations

This research study examined key experiential and demographic factors associated with sport consumers’ choice of online ticketing platforms. The research applied the technology acceptance model (TAM) to examine how trust, official sponsorship, user interface design, and price consciousness are associated with consumers’ choice between different online ticketing platforms.. Data were collected from 312 adult sport consumers in the United States through an online survey distributed across six Reddit communities focused on ticketing or research activities. Participants included individuals who bought tickets to professional sports events and attended these events during the last 12 months. The expert review process and two …

Further Characterization Of The Fungal Effector Mvlg-01732 In Planta And Heterologous Expression Of Fungal Effectors In Different Smut Fungi., Joseph Paul Ham

Electronic Theses and Dissertations

Host-pathogen interactions in smut fungi are characterized by effector proteins and their role in infection. The goal of this work is to better understand these interactions by further characterizing an effector from Microbotryum lychnidis-dioicae and heterologously expressing this and other effectors in heterologous species to see if the range of these effectors can play a role in pathogenicity when expressed in distantly and closely related fungal species. These effectors have been attuned over time to their host plant but have homologous interactors in other plant species. In this study, Microbotryum lychnidis-dioicae, Sporisorium reilianum, and Ustilago maydis, were all used …

Synthesis, Characterization, And Chemical Reactivity Of Calcium-Alginate Hydrogel Beads Containing Metal Nanoparticles And Nanoclusters., Rajiv Kumar Singh

Electronic Theses and Dissertations

This dissertation explores the synthesis, stability, and reactivity of various metal nanoparticles (NPs) and nanoclusters (NCs) of varied size and stabilizers contained within millimeter-sized calcium alginate (Ca-Alg) hydrogel polymer beads. Hydrogel beads synthesized by combining sodium alginate with Au or Ag NPs stabilized with trisodium citrate (Cit) and adding dropwise into a 4.0 M Ca²⁺ solution remained stable and contained within the beads. Those synthesized Au, Pd and AuPd NCs stabilized with glutathione (SG) became partially released from the hydrogel within a day. The synthesis of beads containing aggregated Cit Au NPs occurs by inducing aggregation with tetrakis(hydroxymethyl) phosphonium …

Integrating Due Process Into Large Language Models., Joshua Paul Johnson

Electronic Theses and Dissertations

This research investigates the ability of large language models (LLMs) to recognize due process issues. Due process is a legal concept focused on the protection of the individual during interactions with government when life, liberty, or property are being impacted. Due process presents both substantive and procedural aspects that are challenging to incorporate into generative artificial intelligence. Through assessing model performance, creating benchmarking techniques, retrieval-augmented generation (RAG), and fine-tuning, this work seeks to measure due process recognition performance and improve performance in identifying due process issues. The results of evaluating larger parameter LLMs such as from Google, Meta, and OpenAI …

Understanding Social And Cognitive Influences In Medical Students' Learning Processes For Step 1: An Interpretivist Case Study., Ashley Elaine Triplett

Electronic Theses and Dissertations

This qualitative interpretivist case study explores, at a singular institution, medical students’ perspectives on the social and cognitive factors influencing the learning process as students prepare for the Step 1 examination. While prior research regarding medical students Step 1 preparation have focused primarily on wellness, stress, and career outcomes, limited studies have examined medical students' lived experiences to navigate what occurs during the learning process while they prepare for this critical exam. Utilizing a qualitative case study approach, this dissertation draws on fourteen student interviews, seven that passed Step 1 on their first attempt, and seven that failed. Findings reveal …

Sensory And Motor Tectothalamic Circuits: Two Sides Of The Same Coin., Nazratan Naeem

Electronic Theses and Dissertations

Integration of sensorimotor information in the visual system has always been an intriguing topic to scientists, yet the subcortical sensory and motor circuits that are essential components of this process have remained elusive. In these studies, we used a blend of classical and contemporary techniques such as viral tracing, immunohistochemistry, optogenetics in-vitro whole cell electrophysiology, and electron microscopy in mice to characterize sensory and motor circuits of the superior colliculus (SC), a conserved visuomotor structure with connections with a wide variety of brain structures, including the thalamus. We focused on two SC cell types: visually responsive widefield vertical (WFV) cells …