Digital Commons Network^™

Bayesian Approaches In Multi-State Markov Models And High Dimensional Time-To-Event Data., Yuchen Han

Electronic Theses and Dissertations

This dissertation consists of two projects. The first one involves nonparametric methods on Continuous Time Markov Chains (CTMCs). The second one is centered around Bayesian shrinkage models for detecting prognostic and predictive biomarkers in high-dimensional clinical data. Both these projects build on methods from across the frequentist and Bayesian paradigm to offer novel solutions. In the first project, we aim to model the nonlinear effects of continuous variables within multistate framework in a non-parametrically by appealing to the rich mathematical framework of Reproducing Kernel Hilbert Spaces (RKHS). Then we adapted the classical Representer Theorem to penalized (squared norm) log-likelihood which …

Exploring Medicaid Stigma In Kentucky., Malea Hoepf Young

Electronic Theses and Dissertations

Health insurance is only one of many factors involved in becoming and staying healthy, but the importance of having coverage in the U.S. cannot be overstated. Medicaid provides health care coverage for millions of Americans, with enrollment increasing dramatically after the Affordable Care Act allowed states to expand eligibility. While there is a great deal of research on the impacts of Medicaid expansion on newly eligible adults, there is little research on negative attitudes towards people using Medicaid, or on Medicaid stigma. This study used qualitative methods to conceptualize stigma around Medicaid through discussions with individuals using Medicaid and enrollment …

Denoising And Super-Resolution Of In-Vitro 4e Flow Mri In A Stenotic Phantom Model Using Physics-Informed Neural Networks., Shrouk M. Wally

Electronic Theses and Dissertations

In recent years, the use of 4D flow MRI has revolutionized cardiovascular imag- ing by providing comprehensive data on blood flow dynamics over time. However, the limited spatial and temporal resolution of this imaging modality can hinder the accurate assessment of complex hemodynamic phenomena. This thesis explores the application of Physics-Informed Neural Networks (PINNs) to enhance the resolution of 4D flow MRI data, thereby improving its clinical utility. PINNs are a class of neural networks that integrate physical laws into their training process. By embedding these physics equations, PINNs can discover the underlying physics of fluid dynamics to produce more …

Novel Sensors, Algorithms And Metrics For Human-Robot Interaction., Henry Lee Reynolds

Electronic Theses and Dissertations

The increased presence and deployment of robotics in sectors such as the medical field results in the demand for robots to, directly and indirectly, interface with people and their environment, making human-robot interaction (HRI) a vital thrust of robotics research. Assistive robots, for example, aid humans in accomplishing tasks or by providing support in the workforce. As the demand for nurses and the aging population increases, the assistive robots deployed will be deeply rooted in environments that require constant interaction with humans. This work contributed to improving aspects of HRI through 1) Expanding accessibility of the methods used for interfacing …

Analysis Of The Relationship Between Flow Patterns In The Post-Stenotic Region Of Model Arteries And Stenosis Severity., Michael Laroche

Electronic Theses and Dissertations

In this study, contour fields of mean age and turbulence kinetic energy (TKE) in the post-stenotic region of model arteries were analyzed to explore their correlation with FFR. While both high and low FFR cases exhibited similarities with an inner low-age region and an outer high-age region, low FFR cases displayed asymmetry in their low-age regions due to eccentric stenosis. Moreover, gradients of age across the artery diameter were more pronounced for low FFR cases. Additionally, low FFR cases demonstrated significantly higher TKE in the post-stenotic blood jet stream compared to high FFR cases that are reflected in low-age boundary …

The Impact Of Internal Curing Additives On Compressive Strength, Shrinkage, And Internal Relative Humidity Of Mortars., Payton Scott

Electronic Theses and Dissertations

Curing is a critical step in concrete construction. When a concrete specimen is properly cured, its shrinkage and early age curling/warping can be reduced, and the concrete strength can be increased. Curing methods can be divided into two categories: traditional external curing and emerging internal curing methods. Internal curing has similar benefits to external curing, such as reduced early-age cracking and shrinkage risk, and increased durability and strength. The purpose of this research is to investigate internal curing additives and their impact on length change, weight change, compressive strength, autogenous shrinkage, and internal relative humidity. Mortar mixtures with lightweight aggregate …

Patterns Of The Use And Perception Of Cannabis Among College Students In Tennessee, Jayla Ruffus-Milner

Electronic Theses and Dissertations

Cannabis has been historically difficult to research due to its federal scheduling. However, as legalization of cannabis medically, recreationally, or both in states across the country has increased, so has the need to address the research gaps that persist. The purpose of this study was to explore the patterns of cannabis use and perceptions of college students in Tennessee, which encompass a demographic of mainly young adults who are typically associated with high usage patterns. The study uses quantitative data collected from an online survey sent to a university in East Tennessee to evaluate associations between students’ age, gender, race/ethnicity, …

Enabling Iov Communication Through Secure Decentralized Clustering Using Federated Deep Reinforcement Learning, Chandler Scott

Electronic Theses and Dissertations

The Internet of Vehicles (IoV) holds immense potential for revolutionizing transporta- tion systems by facilitating seamless vehicle-to-vehicle and vehicle-to-infrastructure communication. However, challenges such as congestion, pollution, and security per- sist, particularly in rural areas with limited infrastructure. Existing centralized solu- tions are impractical in such environments due to latency and privacy concerns. To address these challenges, we propose a decentralized clustering algorithm enhanced with Federated Deep Reinforcement Learning (FDRL). Our approach enables low- latency communication, competitive packet delivery ratios, and cluster stability while preserving data privacy. Additionally, we introduce a trust-based security framework for IoV environments, integrating a central authority …

Consultation Versus Direct Special Education Services And Postschool Outcomes For Individuals With Disabilities As Assessed By Indicator 14 Data, Callie Welch

Electronic Theses and Dissertations

There is abundant research relating to transition supports and services for students with disabilities as they move out of high school into adulthood; however, relatively little is known about the relationship between the type of special education services they received and their postschool outcomes. Guided by the Social Cognitive Career Theory (SCCT) and Tennessee’s Indicator 14 survey, I sought to better understand the relationship between the type of special education services received in high school and student further schooling or employability after graduation. Data were drawn from Indicator 14 surveys from 2021 and 2024 conducted by a rural school district …

Moral Disengagement And The Tendency To Engage In Academic Dishonesty In Prelicensure Nursing Students, Sarah Guimaraes

Electronic Theses and Dissertations

Despite decades of research, academic dishonesty remains a significant concern in nursing education. The connection of academic dishonesty to dishonest clinical practice presents a moral imperative for nurse researchers to find new facets of understanding these phenomena. Literature regarding moral disengagement in health care is minimal and is even less prevalent in the context of nursing education. The purpose of this study was to determine the effects of moral disengagement on prelicensure nursing students’ tendencies to engage in academic dishonesty in their last or next to last semester of a nursing program. A correlational design via survey method was used. …

Exploring The Diagnostic Potential Of Radiomics-Based Pet Image Analysis For T-Stage Tumor Diagnosis, Victor Aderanti

Electronic Theses and Dissertations

Cancer is a leading cause of death globally, and early detection is crucial for better

outcomes. This research aims to improve Region Of Interest (ROI) segmentation

and feature extraction in medical image analysis using Radiomics techniques

with 3D Slicer, Pyradiomics, and Python. Dimension reduction methods, including

PCA, K-means, t-SNE, ISOMAP, and Hierarchical Clustering, were applied to highdimensional features to enhance interpretability and efficiency. The study assessed the ability of the reduced feature set to predict T-staging, an essential component of the TNM system for cancer diagnosis. Multinomial logistic regression models were developed and evaluated using MSE, AIC, BIC, and Deviance …

Stigma Reduction And Resiliency Training For First Responders (Srrt-Fr): A Feasibility And Initial Efficacy Evaluation, Thalia P. Nicholson

Electronic Theses and Dissertations

First responders, especially law enforcement, frequently encounter individuals experiencing substance use concerns. Previous research has documented that a greater understanding of substance use disorders promotes a decrease in stigmatizing perspectives. We present a novel approach to training law enforcement officers to improve their interactions with community members exhibiting substance use disorders, while also promoting their professional well-being. The present study sought to evaluate the feasibility and acceptability of the Stigma Reduction and Resiliency Training for First Responders (SRRT-FR) in a sample of law enforcement officers, as well as its efficacy in decreasing stigmatizing perspectives towards substance use disorders and increasing …

Electrocatalytic Reduction Of Hydrogen Peroxide At Paraffin-Sealed Nitrogen-Doped Carbon Fiber Ultramicroelectrodes, Yakubu Gausu Mohammed

Electronic Theses and Dissertations

Compared to unmodified carbons and even some metal materials, nitrogen-doped carbons have been found to exhibit better performance for reducing oxygen-oxygen bonds, a key step in electroreduction of both O₂ (an important reaction in energy applications) and H₂O₂ (an important reaction in sensing and biosensing). Previous studies from our lab revealed that thermal decomposition of urea in the presence of carbon fiber (CF) results in N-doped that exhibited good electrocatalytic properties for H₂O₂ reduction. However, previous methods of sealing ultramicroelectrodes (UMEs) made from N-doped CF using laser heating of borosilicate capillaries and epoxy …

Adjunct Faculty Experiences During The Covid-19 Pandemic: A Narrative Analysis, James Bernard

Electronic Theses and Dissertations

The purpose of this research was to explore the impacts of the COVID-19 pandemic on the experiences of adjunct faculty. The COVID-19 pandemic resulted in unparalleled disruption around the globe. Challenges that were faced in higher education included health and safety protocols, social distancing, emergency remote teaching, and closing campuses while trying to maintain quality of the education and perceived value for the student.

Adjunct faculty play a significant role in higher education, teaching and supporting academic programs. Given the reliance on the use of adjunct faculty and recognizing the link between job satisfaction and performance, the experiences of adjunct …

An Application Of An In-Depth Advanced Statistical Analysis In Exploring The Dynamics Of Depression, Sleep Deprivation, And Self-Esteem, Muslihat Gaffari

Electronic Theses and Dissertations

Depression, intertwined with sleep deprivation and self-esteem, presents a significant challenge to mental health worldwide. The research shown in this paper employs advanced statistical methodologies to unravel the complex interactions among these factors. Through log-linear homogeneous association, multinomial logistic regression, and generalized linear models, the study scrutinizes large datasets to uncover nuanced patterns and relationships. By elucidating how depression, sleep disturbances, and self-esteem intersect, the research aims to deepen understanding of mental health phenomena. The study clarifies the relationship between these variables and explores reasons for prioritizing depression research. It evaluates how statistical models, such as log-linear, multinomial logistic regression, …

Evaluating The Impact Of An Experimental Intervention On Reducing Social Anxiety Through Impression Efficacy Changes, Alexandria Dismuke

Electronic Theses and Dissertations

Social anxiety is a prevalent and harmful experience, predicting negative outcomes even for those not reaching clinical levels. While evidence-based treatments are well-documented for Social Anxiety Disorder, simple and accessible interventions for subclinical samples are a valuable endeavor for research. The current study aimed to test an experimental task for reducing social anxiety through increasing participants’ impression self-efficacy. A secondary goal was to explore the impacts of and responses to positive and neutral feedback. The primary hypothesis was that condition would predict changes in social anxiety indirectly through changes in impression self-efficacy. Participants (n=127) completed a structured interaction with a …

The Role Of Cardiac Mitochondria In Arrhythmias And Sudden Unexpected Death In Epilepsy In Models Of Dravet Syndrome, Jessa L. Aldridge

Electronic Theses and Dissertations

Dravet Syndrome (DS) is a pediatric epilepsy disorder. Individuals with DS are at increased risk of Sudden Unexpected Death in Epilepsy (SUDEP). One mechanism implicated in the pathology of SUDEP is cardiac arrhythmias. A central element involved in cardiac regulation is mitochondria. In the heart, mitochondria maintain cardiomyocyte energy (ATP) generation and ion homeostasis but also produce harmful reactive oxygen species (ROS) byproducts. We hypothesized that deficits in cardiac mitochondria could underlie arrhythmias and SUDEP in two independent mouse models of DS. Mitochondria produce ATP through the mitochondrial respiratory chain, also called electron transport chain, comprised of a series of …

A Comparison Of Maxent Models For Aedes Aegypti Species Distribution In South America Utilizing Different Bioclimatic And Environmental Variables, Matthew Beer

Electronic Theses and Dissertations

Aedes aegypti is the principal vector for dengue transmission across large areas of the world. Understanding where this critically important vector lives is paramount to preventing the continued expansion of dengue globally. Using 1981-2010 bioclimatic (bioclim) variables, as well as additional environmental variables and elevation data, multiple MaxEnt models were constructed for Ae. aegypti within the South American continent to identify ecologically important variables and areas of persistent high suitability. All models had acceptable AUC scores (> 0.70), indicating accurate model fitting. Annual mean precipitation and temperature were found to be important model variables; however, when added, humidity became the …

Student Achievement In The State Of Tennessee Through Virtual Learning In Asynchronous, Bisynchronous, And Hybrid Approaches, Lindsey Weeden

Electronic Theses and Dissertations

This study was used to investigate the differences in asynchronous, bisynchronous, and hybrid learning environments in student achievement in online schools. Utilizing quantitative data analysis, the research examines student growth data, chronic absenteeism, graduation rates, and ACT scores across these modalities. The research holds significant implications for educators, policymakers, and stakeholders in enhancing the quality of online education. The results may contribute to the ongoing dialogue surrounding effective pedagogical practices in the digital age by providing evidence-based insights into the strengths and weaknesses of each instructional mode. By addressing the challenges of the digital divide, the results may be used …

Enhancing Ethical Competency: A Review Of Ethical Instruction For Law Enforcement, Alexis Turner

Electronic Theses and Dissertations

As public confidence in policing has dropped, demand for ethical behavior from law enforcement officers has grown, and correspondingly, a better understanding of ethics training and ethical acquisition processes has become paramount. Though much literature exists on related topics, understanding of the ethics training for law enforcement officers as it currently exists, has remained murky. This research aimed to gain a better understanding of ethics training for law enforcement in the United States, and as such, to fill the aforementioned gap in the literature. Four research questions were explored in this study including the understanding of current pre-service and in-service …

Food Insecurity And Self-Rated Health Of Older Adults In Appalachia, Sarah Kelley

Electronic Theses and Dissertations

Food insecurity is prevalent in the United States. Although older adults experience food insecurity at lower-than-average rates, this population is vulnerable to the nutrition and health related implications. Food insecurity is tied to both a diminishment of diet quantity and quality, and is associated with incidence of chronic disease, loss of functional status, and quality of life. This survey seeks to fill a gap in research by looking into the prevalence of food insecurity among older adults in Northeast Tennessee, associations between food insecurity and self-rated health, and associations between food insecurity and geographical limitations.

The Effects Of A Period Of Match Congestion On Countermovement Jump Height And Match Performance Variables In Ncaa Division I Female Soccer Players, Fiona Dodge

Electronic Theses and Dissertations

Effects of a congested match period on countermovement jump height (CMJ) and match performance variables were examined over the course of a D-I female soccer season. Twenty-one female collegiate soccer players (20.3 ± 1.8 yrs, body mass (kg): 62.3 ± 7.3, height (cm): 168.9 ± 6.1, body fat (%): 23.0 ± 3.7. performed CMJ testing prior to regular season matches. Global Positioning System (GPS) was used to assess physical match performance, while pre- and post-season lab and field-based testing was also performed. Analysis of variance trend analyses (ANOVA) were conducted using a linear mixed-effects model (LMM) to examine trends in …

The Influence Of Teaching Digital Resources Of Myplate On Nutrition Knowledge, Attitudes, And Practice (Kap) For Healthy Eating Habits Of Children, Afaf Alsofyani

Electronic Theses and Dissertations

This study examines the influence of teaching digital resources of MyPlate on the nutrition knowledge, attitudes, and practices (KAP) related to healthy eating habits among first and second-grade students. A pre-and post-assessment of this quasi-experimental research study measured the baseline KAP levels of 45 participants regarding healthy eating habits. Students were divided into three groups: digital MyPlate (n =16), pencil-and-paper (n =15), and control (n =14). Following the pre-assessment, an intervention was conducted involving teaching MyPlate and the five food groups. A post-assessment was then implemented to measure the change in KAP levels resulting from the intervention. …

Trauma Informed Schools: Investigating K-12 Educator Perceptions From Professional Learning To Implementing Practices, Kelsey Cupp

Electronic Theses and Dissertations

The purpose of this quantitative study was to further the understanding on how access to trauma-informed professional learning changed research-based practices in classroom and school-wide settings in K-12 schools. The guiding question for this quantitative study was: How has trauma-informed professional learning influenced changes in research-based practices in school-wide and classroom settings in K-12 schools? This research assessed the perceptions of elementary, middle, and high school teachers in one school district to investigate access to trauma-informed professional learning and potential changes in research-based practices in school-wide and classroom settings. Participants were teachers, in Northeast Tennessee, employed in urban schools implementing …

Pilz Domain-Containing Proteins Regulate Motility In Acinetobacter Baumannii, Gabriel Smith

Electronic Theses and Dissertations

Acinetobacter baumannii is an increasingly multidrug-resistant pathogen contributing to hospital-acquired infections, necessitating a greater understanding of how it interacts with its surroundings. Many bacteria utilize different methods of bacterial motility to move about and interact with these surroundings. A bacterial second messenger, cyclic diguanosine monophosphate (c-di-GMP), can regulate various motility factors that are potentially advantageous for survival in and adaptation to their environment. Concentrations of c-di-GMP are regulated by specific synthesizing and degrading enzymes. Controlled levels of c-di-GMP allow interaction between the c-di-GMP and its binding effectors that induce changes in bacterial phenotypes such as biofilm formation and motility. A …

Strength And Endocrine Adaptations From The Combined Use Of Accentuated Eccentric Loading And Cluster Sets During A Strength Endurance Training Block, Kurt Mcdowell

Electronic Theses and Dissertations

The purpose of this study was to investigate the chronic effects of accentuated eccentric loading (AEL) paired with cluster sets (CS) on dynamic and maximal strength, the endocrine system, and body composition. Seventeen recreationally active subjects (male = 11, females = 6, age = 23.05 ± 4.07, height = 172.09 ± 9.98, body mass = 81.29 ± 22.18, back squat to body mass ratio = 1.55 ± 0.33, bench press to body mass ratio = 1.06 ± 0.28) participated in one familiarization week, 2 weeks of testing, and 4 weeks of training. A strength-endurance block (4 wks) was used for …

An Exploratory Study Of Flora Poaching In Central Appalachia, Mckinley Bowers

Electronic Theses and Dissertations

The purpose of this study was to explore perceptions of flora poaching among conservation officers, park rangers and botanists within Central Appalachia. Though some work has sought to understand poaching in other forms, such as animal poaching, little is known regarding the poaching of plants. This is especially true within the Appalachian Region. Several research questions were explored in this study, including the types of flora being poached, the characteristics of poachers, poaching tactics utilized, and deterrence measures that are currently in place. Data were collected through semi-structured interviews with 20 individuals working in the field. Findings contribute to the …

Informed Consent Document Delivery: Effects On Appalachian Caregivers' Comprehension, Trust In Researchers, And Willingness To Participate, Tess A. Simpson

Electronic Theses and Dissertations

The purpose of the present study was to investigate whether altering an informed consent document (ICD), in ways that either promote or inhibit accessibility, would affect potential participants’ willingness to participate in a child development laboratory-based study. Specifically, I was interested in assessing the willingness to participate of historically underrepresented groups, especially Appalachian caregiver-child dyads. I altered three parameters of a previously approved and employed ICD to explore whether these parameters impacted Appalachian caregivers’ comprehension of the study, willingness to participate, and trust in the researchers. The manipulated parameters included reading level, utilization of illustrative pictures, and inclusion of text-to-speech …

Dengue And Climate Change: Assessing Potential Future Areas Of Concern For Transmission In The United States, Matthew Beer

Electronic Theses and Dissertations

Background: Global climate change severely impacts human life, particularly health, as rising temperatures and extreme weather affect physical and mental well-being. Climate change can also alter the risk factors and epidemiology of infectious diseases, notably vector-borne diseases (VBDs), including those transmitted by mosquitoes. The Aedes mosquito, responsible for dengue, poses a significant threat due to its prevalence vector. Dengue prevention lacks effective methods beyond vector control, and the current vaccine has limitations, emphasizing the need for intensified research and prevention strategies to mitigate the expanding dengue burden worldwide. The goal of these studies was to establish a novel risk index …

Transatlantic Memory And Identity: The Legacy Of Colonel Heg And The 15th Wisconsin In Norway And Norwegian America, Remi Berg

Electronic Theses and Dissertations

While memory studies of the American Civil War flourishes, ethnic and immigrant perspectives remain obscured. This project attempts to uncover how Norwegian-Americans remembered the 6000 Norwegian immigrants who fought in the Union Army. It explores the processes behind commemoration of Colonel Hans Christian Heg and the 15th Wisconsin Infantry Regiment from 1914 to 1928. It reveals that Norwegian-Americans commemorated Colonel Heg on three different and connected levels. Nationally, Norwegian-Americans raised a statue of Heg in Wisconsin after the individual determination of Waldemar Ager to challenge nativism and Americanization. Transnationally, Ager cooperated with the organization Nordmands-Forbundet who facilitated the erection of …