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A Comparison Of Logistic, Ridge, And Lasso Regression With Heart Failure Risk Data: Effects Of Sample Size, Predictor Correlation, And Predictor Weight On Outcome Accuracy, Mahmoud M. Aljuhani

Electronic Theses and Dissertations

Logistic Regression (LR), LASSO regression, and RIDGE regression are standard classification techniques for predicting a dichotomous output. Since these methods are applied for similar purposes and have different features, it is crucial to evaluate the performance of these methods under different controlled conditions. With this information, researchers can apply the optimal method for specific conditions.

Following previous research, which reported the effects of conditions such as sample size and multicollinearity on the performance of the classification methods, this research focused on the effects of when sample size, level of predictor collinearity, and predictor variable weight are controlled on the performance …

Neurocognitive And Momentary Assessment Of Fear-Based Mechanisms Underlying The Transition From Partial To Full Remission In Anorexia Nervosa., Caroline Christian

Electronic Theses and Dissertations

Background. Anorexia nervosa (AN) is a serious psychiatric illness, with high mortality, chronicity, and societal costs. Many individuals with AN that are weight restored do not to fully remit from cognitive-affective symptoms (e.g., fear of weight gain) maintaining the disorder, contributing to the poor outcomes. This critical stage of AN is called partial remission. AN is characterized by high levels of fear and avoidance, which may prevent full remission; however, the role of fear-based mechanisms (i.e., fear approach; avoidance) in partially-remitted AN remains untested. Methods. In the current study (N = 55 partially-remitted AN), participants completed two behavioral paradigms …

Examining Effective And Realized Healthcare Access In The West South Central Division., Katherine Cameron

Electronic Theses and Dissertations

This study explores realized and effective access domains outlined by Andersen’s Behavioral Model of Health Services Use. Exploring other domains of access is critical to understanding how the healthcare system functions (Kirby & Yabroff, 2020). This study evaluates rural-urban and racial/ethnic differences in access to care using two underresearched domains of healthcare access. It also allows for exploring access disparities within rural communities amongst minority populations. This dissertation is divided into five chapters. Chapter One provides an overview of health disparities and inequities and a brief overview of the study. Chapter Two details a high-level history of racism and its …

Death Of A Bacterium: Exploring The Inhibition Of Staphylococcus Aureus By Burkholderia Cenocepacia., Tiffany Brandt

Electronic Theses and Dissertations

Antimicrobial resistance is a phenomenon of increasing concern as antimicrobial overuse and misuse eliminate current therapeutic options, ushering society into a post-antimicrobial era. Antibiotic discovery and synthesis efforts are urgently needed to counter the increasing burden of antimicrobial resistance. Staphylococcus aureus is a causative agent of a variety of clinical manifestations including bacteremia, endocarditis, soft tissue infection, osteomyelitis, and device-related infections. S. aureus infection presents additional treatment challenges due to its capacity for biofilm formation, which is a mode of growth that confers protection from antibiotics and physical elimination, and the emergence of antibiotic resistant strains, including methicillin-resistant S. aureus …

Anion Alloying Of Iii-V Semiconductors For Water Splitting., Sonia Calero-Barney

Electronic Theses and Dissertations

The challenge of solar energy conversion and storage translates into the discovery and development of semiconductor materials that can transform sunlight energy into electricity and/or high-energy-density fuels in a cost-effective way. From the solar energy conversion perspective, cation-alloyed III-V solar cells hold record-breaking energy conversion efficiencies, while anion-alloyed III-V’s are particularly interesting for photoelectrochemical hydrogen generation. The major challenge for the adoption of III-V-based technologies lies in the high manufacturing costs of established synthesis techniques and the difficulty to control the composition of ternary alloys. One of the materials investigated in this work is GaSb_zP_1-z. Thermodynamic …

The Effects Of Stigma On Quality Of Life And Psychological Outcomes In Participants With Varying Reports Of Subjective Cognitive Decline., Lauren Flaherty

Electronic Theses and Dissertations

Background: Diagnostic labels such as cognitive impairment, dementia or MCI often carry associated stigmatization. Stigma can lead to social isolation and rejection; increasing the likelihood of loneliness, depression, and anxiety. Depression and anxiety can be predictive of cognitive function; depression and anxiety are linked to stigma. Subjective cognitive decline (SCD) can be indicative of actual cognitive impairment. Subjective impairment and stigma can significantly predict quality of life. The aim of the proposed dissertation study was to explore whether higher SCD scores associate with more internalized stigma, and if this stigma mediates the relationship between SCD and depression, SCD and …

Nonlinear Observers For Burning Zone Temperatures And Torque Estimation Of The Rotary Cement Kiln., Bhagyashri Aditya Bhagwat

Electronic Theses and Dissertations

Due to consistent expansion in the infrastructure and housing sectors worldwide have given a new way for the rapid growth of global cement market. Increased global demand for the cement production makes the attractive research topic which can lead to the quality and overall efficiency of the product. Measurement of the temperature in the burning zone is vital to maintain product quality and kiln efficiency in the cement industry. Often the BZT is un-measurable due to internal kiln conditions, dusty environment, extreme heat, harshness for example and this leads to kiln not being driven as efficient as possible. Multi-physics tools …

Understanding Neuroanatomy In A Virtual 3d Environment: Creation And Use Of A New Survey Tool To Evaluate The Effectiveness Of 3d Software In Neuroanatomy Education For Understanding Superficial And Deep Brain Structures., Akash Khare

Electronic Theses and Dissertations

Studying cross-sections is a critical approach to learning and testing knowledge in neuroanatomy and the role of 3D technologies have been gradually increasing in medical education, especially after the COVID-19 pandemic. A study was conducted in a quasi-experimental one-group pre-post interventional design in an online setting by creating and evaluating the effectiveness of a virtual lab in neuroanatomy for all neuroscience students enrolled in the Fundamentals of Neuroscience course in our department at the University of Louisville. Study modules were created using the 2D resources used in previous years and 3D web applications of Visible Body and AnatomyLearning.com software. A …

Sro Roles And Teacher Behavioral Intervention Strategies: An Analysis On Behavioral Approaches And Student Suspensions., Ivan Benitez

Electronic Theses and Dissertations

Recently there have been nationwide calls for schools to end their contracts with local police departments in efforts to remove school resource officers (SROs) due to their criminalizing effect on students. Aiming towards racial equity in safety and discipline, advocates have suggested re-envisioning discipline through a restorative lens to minimize student harm. One approach which has been promising in student outcomes are behavioral intervention strategies. The current study contributes to the literature by examining the direct effects of SRO roles and teacher behavioral intervention strategies on student suspensions. Using factor analysis, I found three SRO roles: law enforcement officer, mentor, …

Reaching Syrians In Need: An Analysis Of Humanitarian Aid In The 21st Century., James Clark

Electronic Theses and Dissertations

The objective of this dissertation is two-fold. One is to critically consider humanitarian aid delivery to and through Syria via a lens that combines the humanities and social sciences. The fields of anthropology, political science and postcolonialism are employed to accomplish this. The second is to investigate the process involved in this delivery amid the country’s ongoing conflict. Combining these two facets provides a view of humanitarian aid as it relates to the conflict in Syria while applying a liberal arts-humanities approach. The introduction establishes the basis to discuss the existence of aid providers and those in need of aid …

Bayesian Methods For Graphical Models With Neighborhood Selection., Sagnik Bhadury

Electronic Theses and Dissertations

Graphical models determine associations between variables through the notion of conditional independence. Gaussian graphical models are a widely used class of such models, where the relationships are formalized by non-null entries of the precision matrix. However, in high-dimensional cases, covariance estimates are typically unstable. Moreover, it is natural to expect only a few significant associations to be present in many realistic applications. This necessitates the injection of sparsity techniques into the estimation method. Classical frequentist methods, like GLASSO, use penalization techniques for this purpose. Fully Bayesian methods, on the contrary, are slow because they require iteratively sampling over a quadratic …

Rehabilitation Length Of Stay In Individuals With Spinal Cord Injury Paraplegia., Sahal Alzahrani

Electronic Theses and Dissertations

Background: Spinal Cord Injury (SCI) is associated with functional and physical limitations as well as psychological challenges. Rehabilitation care is crucial to SCI individuals’ overall health. It is recommended that individuals with SCI receive an intensive and early rehabilitation care to improve their health and avoid medical complications. Hospitals and rehabilitation facilities use length of stay (LOS) as a proxy to quantify rehabilitation care and a measure for quality of care. Objectives: This dissertation has three aims: 1) to identify factors associated with rehabilitation LOS in paraplegia populations, 2) to examine trends of inpatients rehabilitation LOS in SCI paraplegia between …

Ideas In Communities: A Micro-Perspective On Entrepreneurial Ecosystems., Malcolm Muhammad

Electronic Theses and Dissertations

Entrepreneurial ecosystems are seen as a stimulant of regional economic growth. Theory-building efforts on entrepreneurial ecosystems has sufficiently established an understanding of the macro-environment; the environmental infrastructure and conditions that support productive entrepreneurship. However, there has been a disproportionate lack of focus on the micro- and group-level dynamics that impact individual entrepreneurs and ventures within ecosystem. This has limited the availability of evidence to explain how and when ecosystems emerge and function at a high level. Therefore, this dissertation examines three distinct microfoundations that can be found in entrepreneurial ecosystem literature – community, learning, and venture development – to move …

Design, Evaluation, And Control Of Nexus: A Multiscale Additive Manufacturing Platform With Integrated 3d Printing And Robotic Assembly., Danming Wei

Electronic Theses and Dissertations

Additive manufacturing (AM) technology is an emerging approach to creating three-dimensional (3D) objects and has seen numerous applications in medical implants, transportation, aerospace, energy, consumer products, etc. Compared with manufacturing by forming and machining, additive manufacturing techniques provide more rapid, economical, efficient, reliable, and complex manufacturing processes. However, additive manufacturing also has limitations on print strength and dimensional tolerance, while traditional additive manufacturing hardware platforms for 3D printing have limited flexibility. In particular, part geometry and materials are limited to most 3D printing hardware. In addition, for multiscale and complex products, samples must be printed, fabricated, and transferred among different …

The Role Of Mri In Diagnosing Autism: A Machine Learning Perspective., Yaser Elnakieb

Electronic Theses and Dissertations

There is approximately 1 in every 44 children in the United States suffers from autism spectrum disorder (ASD), a disorder characterized by social and behavioral impairments. Communication difficulties, interpersonal difficulties, and behavioral difficulties are the top common symptoms. Even though symptoms can begin as early as infancy, it may take multiple visits to a pediatric specialist before an accurate diagnosis can be made. In addition, the diagnosis can be subjective, and different specialists may give different scores. There is a growing body of research suggesting differences in brain development and/or environmental and/or genetic factors contribute to autism development, but scientists …

Effects Of Top-Down Attention And Individual Differences On Recognition Memory And Recollective Experience., Anna Kelley

Electronic Theses and Dissertations

Memory accuracy and detail hold practical importance, and psychology has studied means to improve memory. One such means is performing visually guided saccades immediately before a memory test. Previous work has found this intervention to improve memory performance, an effect dubbed Saccade-Induced Retrieval Enhancement or SIRE. The top-down attentional control account posits that SIRE occurs because saccades activate attentional control regions in the brain, which contributes to executing top-down attentional control when searching memory. The current experiment tested this account of SIRE by attempting to replicate previous results and investigating whether a different attentional task, the Revised Attention Network Test …

The Impact Of Volatile Organic Compound Exposure On Subclinical Biomarkers Of Cardiovascular Injury., Breandon Taylor

Electronic Theses and Dissertations

Pollution has been identified as the leading environmental cause of non-communicable disease and premature deaths globally. Volatile organic compounds (VOCs) are gaseous chemical constituents of pollution derived from a variety of sources, including industrial solvents and byproducts, automobile exhaust, tobacco smoke, cleaning supplies, and personal care products. VOCs are also abundant at various Superfund and Hazardous Waste Sites. Emerging data suggest that VOC exposure is associated with several adverse health outcomes, including cardiovascular disease (CVD). VOCs and their metabolites can potentially damage the endothelial lining of blood vessels, resulting in perturbed vascular function and vascular inflammation. We hypothesize that VOC …

Investigation Of Human N-Acetyltransferases (Nat1 And Nat2) Genetic Polymorphisms In Susceptibility To Aromatic Amine And Alkylaniline Genotoxicity., Mariam Habil

Electronic Theses and Dissertations

Arylamine N-acetyltransferases, NAT1 and NAT2, catalyze the detoxification and/or activation of carcinogens. Single nucleotide polymorphisms or SNPs result in different human NAT1 and NAT2 genotypes. We hypothesize that different NATs alleles will impact levels of N-acetylation, HPRT mutations, DNA damage and oxidative stress induced by carcinogens. NER-deficient Chinese hamster ovary (CHO) cells transfected with human CYP1A2 and NAT1*4, NAT1*14B, NAT2*4, NAT2*5B or NAT2*7B have been used to investigate N-acetylation of benzidine, β-naphthylamine (BNA), and 4, 4’-methylene bis (2-chloroaniline) (MOCA) as aromatic amines and 3,4-dimethylaniline (3,4-DMA) as one of alkylanilines and their associated toxicity. Our …

A New Direction For Public Understanding Of Science: Toward A Participant-Centered Model Of Science Engagement., Christopher Rickels

Electronic Theses and Dissertations

Engaging the public with science is not an easy task. When presented, scientific findings, public health recommendations, and other scientific information filter through the personal values, beliefs, and biases of members of the public. Science communicators must contend with these differences in order to be effective in cultivating a public understanding of science. Given the importance of scientific understanding for living well in a complex world, increasing science understanding through science engagement is imperative. The field of public engagement with science is dichotomized by a public information deficit approach and a contextualist approach. The deficit approach prizes the factual content …

Metabolic Foundations Of Exercise-Induced Cardiac Growth., Kyle Fulghum

Electronic Theses and Dissertations

Regular aerobic exercise promotes physiological cardiac growth, which is an adaptive response thought to enable the heart to meet higher physical demands. Cardiac growth involves coordination of catabolic and anabolic activities to support ATP generation, macromolecule biosynthesis, and myocyte hypertrophy. Although previous studies suggest that exercise-induced reductions in cardiac glycolysis are critical for physiological myocyte hypertrophy, it remains unclear how exercise influences the many interlinked pathways of metabolism that support adaptive remodeling of the heart. In this thesis project, we tested the general hypothesis that aerobic exercise promotes physiological cardiac growth by coordinating myocardial metabolism to promote glucose-supported anabolic pathway …

The Impact Of Pegylation On Cellular Uptake And In Vivo Biodistribution Of Gold Nanoparticle Mri Contrast Agents., Nagwa El-Baz

Electronic Theses and Dissertations

Gold nanoparticles (GNPs) have become a pivotal platform for the delivery of pharmaceutical and diagnostic agents as well as for general therapeutic purposes. Despite their potential for use in biomedicine, their interaction with serum proteins is crucial as it could change their biological profile due to the formation of a protein corona, which can affect their delivery to target tissues in the body. Grafting the GNPs with polyethylene glycol (PEG) is widely used in research to decrease opsonization of the particles by serum proteins and decrease the uptake by the reticuloendothelial system. Here in this dissertation, we have developed a …

Age-Related Differences In The Relationship Between Activity Familiarity And Well-Being., S. Kelly Shryock

Electronic Theses and Dissertations

Background and Objectives: This study explored age-related differences in the relationship between activity novelty/familiarity and well-being, conceptualized within theories including Selection, Optimization, and Compensation (SOC), Self-Determination Theory (SDT), and Socioemotional Selectivity Theory (SST). For all ages, participation in activities has been shown to enhance well-being. Known mediators of this relationship include psychological, physical, and psychosocial benefits. It is less clear what types of experiences are optimal across the lifespan. Research Design and Methods: A online cross-sectional, correlational study (N= 200) was conducted. Measures included demographic data, ratings of three self-identified recent activities, three activity choices of familiar or …

Wet Chemical Synthesis And Properties Of Argyrodite Sulfide Solid Electrolytes For Solid State Lithium Batteries., William Arnold

Electronic Theses and Dissertations

The commercialization of the lithium-ion battery (LIB) in 1991 was responsible for the explosion in portable electronic technologies that has been seen over the past 30 years. With the advent of electric vehicles and other high-powered technologies, there is tremendous demand for LIBs with higher energy density and high safety. To achieve this, new electrode materials must be explored. The obvious choice of anode material would be pure metal lithium, which has a theoretical specific capacity of 3860 mAh g^-1 . Unfortunately, metal lithium anodes have not been widely commercialized due to their tendency to react violently with the …

Teachers' Perceptions Of Professional Development And Pedagogical Practice: A Study Of A Kentucky Suburban School District., Rachelle Bramlage-Schomburg

Electronic Theses and Dissertations

Professional development supports teacher growth and enhances pedagogical practice. Teachers in Kentucky must complete annual professional development hours and districts must develop a professional development plan tied to research that supports high-quality professional development. This qualitative case study takes place in a rural district, Bullitt County, where I investigated the teachers’ perception of a customized professional development, Thinking Focus Cohort (TFC), and its impact on their pedagogical practice. While a body of research exists on high quality professional development, there is a lack of research on the effectiveness of it, in particular a year-long cohort model with curriculum centered around …

A Mixed Methods Assessment Of Menstrual Hygiene Management And School Attendance Among Schoolgirls In Edo State, Nigeria., Madeline Tomlinson

Electronic Theses and Dissertations

Menstrual hygiene in lower-middle-income countries (LMICs) is limited and has been linked to many health, educational and social effects. However, the prevalence, details, and impact of menstrual hygiene management have not been well characterized in rural and peri-urban settings across Nigeria. The overall purpose of this research was to investigate menstrual hygiene management (MHM) among adolescent schoolgirls in peri-urban areas of Edo State, Nigeria; and to determine the educational consequences associated with poor MHM. MHM was measured using previously validated questions that were adapted after a formative assessment of MHM within the Edo State community. We used a mixed methods …

Investigating The Income Academic Achievement Gap: An Exploration Of The Roles Of Mindfulness And Self-Concept Clarity In Low-Income College Students., Natalie Burke

Electronic Theses and Dissertations

The purpose of the current study was to examine whether linguistic patterns previously associated with trait mindfulness and self-concept clarity in low-income college students’ application essays are associated with academic performance and psychosocial variables. The aims of the study were as follows: 1) Explore relations between linguistic markers that have been previously associated with higher mindfulness/self-concept clarity and GPA and 2) Explore relations between linguistic markers that have been previously associated with higher mindfulness/self-concept clarity and anxiety/depression. Participants were 54 undergraduate students in the Cardinal Covenant program (a scholarship program for students from low-income families) who began college in the …

Self-Regulation In Young School-Aged Children With Williams Syndrome., Holley Arnold

Electronic Theses and Dissertations

My dissertation included two manuscripts which broadly focused on the self-regulation abilities of young school-aged children with Williams syndrome (WS), a rare neurodevelopmental disorder. Children with WS often exhibit mild to moderate intellectual disability (Kozel et al., 2021), impairments in behavioral and emotional regulation (Greiner de Magalhães et al., 2022), low effortful control (Leyfer et al., 2012), and deficits in adaptive skills (Brawn & Porter, 2018). In the first manuscript, the performance of children with WS on a gift-wrap delay of gratification task was characterized. In the second manuscript, the concurrent effects of the ability to regulate emotions, the ability …

Defining The Impact Of Clinically Modeled Hindlimb Stretching, Exercise, & Inactivity On Functional Recovery After Spinal Cord Injury., Greta Cesarz

Electronic Theses and Dissertations

Spinal cord injury (SCI) is a devastating, life altering event that affects approximately 282,000 Americans. The most obvious side effect of SCI is paralysis due to damage to the spinal cord that disrupts ascending and descending pathways as well as central pattern generating circuitry. In addition to paralysis, patients suffer from other debilitating side effects including altered cardiovascular function, autonomic dysreflexia, neuropathic pain, spasticity, and contractures. In contrast to humans, rodents display spontaneous locomotor recovery following incomplete SCI due to in-cage activity/training. Previously, our laboratory has studied the effect of lack of in-cage training by utilizing custom designed rodent wheelchairs. …

Cadence And Range Of Motion Modulate Pedal Force In A Rat Model Of Motorized Cycling After Spinal Cord Injury., Gregory States

Electronic Theses and Dissertations

Motorized cycling (MC) can be utilized post-spinal cord injury (SCI) in patients who lack the strength and/or stability to participate in traditional physical exercise interventions. MC has been applied with the goal of improving locomotor function or cardiovascular health in both human and animal models of SCI. However, a discrepancy exists between the results of human and animal studies of MC, particularly regarding cardiovascular outcomes. Despite the abundance of studies in both humans and animals, the mechanism behind the improvements in cardiovascular function following MC are poorly understood. We posited that increased venous return during MC is likely due to …

Iot In Smart Communities, Technologies And Applications., Muhammad Zaigham Abbas Shah Syed

Electronic Theses and Dissertations

Internet of Things is a system that integrates different devices and technologies, removing the necessity of human intervention. This enables the capacity of having smart (or smarter) cities around the world. By hosting different technologies and allowing interactions between them, the internet of things has spearheaded the development of smart city systems for sustainable living, increased comfort and productivity for citizens. The Internet of Things (IoT) for Smart Cities has many different domains and draws upon various underlying systems for its operation, in this work, we provide a holistic coverage of the Internet of Things in Smart Cities by discussing …