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Enlarged Perivascular Spaces Are A Clinically Relevant Neuroimaging Biomarker Of Cerebral Small Vessel Disease, Timothy Justin Libecap

Theses and Dissertations--Neuroscience

Vascular contributions to cognitive impairment and dementia (VCID) represents the intersection between cerebrovascular disease and cognitive decline. Cerebral small vessel disease (cSVD) is an important risk factor that may precede the onset of VCID by years. cSVD is characterized by in-vivo neuroimaging biomarkers including enlarged perivascular spaces (ePVS). PVS are the site of interchange between interstitial fluid (ISF) and cerebrospinal fluid (CSF) which is believed to play a role in the removal of brain waste. Reduced clearance may lead to enlargement of the PVS and subsequent accumulation of toxic solutes characteristic of neurodegeneration. Given the presence of ePVS in brain …

Fathers’ Perspectives On The Role Of Spirituality In Substance Misuse Disorder Treatment And Engaging With Their Children, Kendra Michelle Eubank

Theses and Dissertations--Social Work

The father's role and the extent of involvement with his children have shifted over the past several decades. As a result, researchers have made considerable advances in understanding paternal influences on child development and families. However, one under-researched topic is how fathers' substance misuse, and the recovery process may influence father involvement and effective co-parenting, and specifically, how spirituality plays a role in that. In this qualitative study, fourteen participants participated in semi-structured interviews. The data revealed two main themes: 1) pillars of a spiritual awakening and 2) applying spirituality to healthy fatherhood engagement.

These findings led to four interpretations: …

The Performance Of Marginal Modeling Methods For Rare Events With Application To Opioid Overdose Mortality And Morbidity, Shawn Nigam

Theses and Dissertations--Epidemiology and Biostatistics

Opioid misuse is a nationwide epidemic, with Kentucky having one of the highest opioid overdose-related fatality rates across all US states. These rates have increased significantly over the past decade, with particularly large increases during the COVID-19 pandemic. This dissertation aims to study the behavior of these increases and the methods for the marginal modeling of count outcomes related to opioid overdose.

Opioid overdose-related fatality rates in Kentucky increased significantly during the COVID-19 pandemic. In this chapter, we characterize the changes in opioid overdose fatality rates in Kentucky and identify associations between potential factors and fatality rates. County-level opioid overdose …

Relationality In Rousseau's Philosophy Of Education, Thayne Cameron

Theses and Dissertations--Philosophy

Jean-Jacques Rousseau’s assertion of Emile that “Our true study is that of the human condition” serves as the foundation for this dissertation, which examines the significance of certain kinds of basic experiential relationships in Rousseau’s philosophy of education. By analyzing the relationships between the self and objects, the self and others, and the educator and the learner, this work elucidates how these interactions underpin Rousseau’s pedagogical views and their implications for fostering personal and social virtue.

The dissertation explores the self-object relationship through affectivity, embodiment, and purposeful activity, demonstrating how direct engagement with objects shapes perceptions and behaviors. It then …

Recovery Capital In A Justice-Involved Population: An Asset-Based Approach To Recovery And Community Reentry, Evan Joseph Batty

Theses and Dissertations--Sociology

The burden of the opioid epidemic demands further efforts to facilitate recovery, particularly for disadvantaged populations and those recently released from prison. After community reentry, individuals face a period of vulnerability as they adjust to new roles and responsibilities to meet their basic needs. Prison-based substance use disorder treatment (SUD Tx) programs provide support to help prepare individuals with SUD for their release and facilitate successful recovery goals after community reentry. This dissertation has three aims: (1) further the understanding of potential barriers and facilitators of recovery after community reentry, (2) assess how prison-levels of recovery capital influence recovery outcomes …

Variable Selection For High-Dimensional Data With Interaction Effects: Methods, Applications, And Inferences, Leiyue Li

Theses and Dissertations--Statistics

For high-dimensional data where the number of variables greatly exceeds the number of observations, selecting important variables while maintaining the required heredity conditions can be challenging. This dissertation is structured into three interconnected parts. In the first part, we propose a variable selection method by implementing a well-known optimization technique, the Genetic Algorithm. An R package was developed to simplify the implementation and usage of the proposed method. We then propose another variable selection method by extending the study from the Genetic Algorithm to a different but related optimization technique, Simulated Annealing. We consider three different hierarchical structures in both …

High-Dimensional Tests And Projection Methods: Subvector Analysis And Matrix Variate Data, Shouryya Mitra

Theses and Dissertations--Statistics

In this dissertation, we study projection-based methods to testing problems for high-dimensional data. We also investigate inferential methods for matrix variate data with block compound symmetry (BCS) covariance structure. The research reported in dissertation consists of three projects.

The first project addresses power loss and ill-conditioned error covariance estimates commonly faced by multivariate tests in high-dimensional settings. To overcome these challenges, previous approaches avoided correlations in constructing test statistics, but this required strong assumptions about covariance matrices and dependence structures. More recently, some methods have incorporated correlations by employing random projection into a lower-dimensional space. We develop a unified framework …

Estimation And Testing Of Nonparametric Effects Of Incomplete Multivariate And Repeated Measures Data, Swetalina Maity

Theses and Dissertations--Statistics

In this dissertation, we investigate three distinct but interrelated problems in analyzing repeated measure data with missing values.

The first project is on semiparametric methods for analyzing repeated measures designs with missing values. A closed-form estimator for the parameters and their asymptotic covariance are derived using block partitioning based on the missing data pattern. We also derive the asymptotic distribution of the estimators and construct test statistics to test hypothesis formulated as linear contrasts of the mean vector.

In the second project, we focus on purely nonparametric methods. In this setup, nonparametric treatment effects are defined as functionals of the …

From Non-Parametric Methods To Self-Supervised Learning: Applications In Edge Detection And Image Denoising, Jiacheng Xu

Theses and Dissertations--Statistics

This dissertation explores advanced methodologies for edge detection and image denoising through the application of both traditional non-parametric methods and modern self-supervised deep learning techniques. Beginning with non-parametric approaches, we refine surface fitting and jump detection criteria to enhance the detection of discontinuous regression surfaces in grayscale images. These foundational techniques are extended to color images, with analyses across RGB and CIELAB color spaces to improve edge detection accuracy. We then introduce a self-supervised neural network model that integrates Masked Modeling into the Bi-Directional Cascade Network (BDCN) framework. This approach shows the potential of reducing the dependency on annotated data …

Investigating A New Drug Target In Alzheimer’S Disease: Nox2, Tiffany Adams

Theses and Dissertations--Pharmacy

Introduction: Alzheimer’s disease (AD) is a neurodegenerative disease with neuropathological changes in the blood-brain barrier that offers possible therapeutic targets. Oxidative stress is one driving factor for AD. NADPH oxidase 2 (NOX2) in the capillary endothelium produces reactive oxygen species, leading to oxidative stress-mediated blood-brain barrier dysfunction. We hypothesized that using a specific NOX2 inhibitor, PhoxI2, has the potential to reduce reactive oxygen species and repair amyloid-β (Aβ)-driven blood-brain barrier leakage in an AD mouse model.

Methods: For this study, 5xFAD (Familiar Alzheimer Disease) mice were treated with vehicle or PhoxI2, a NOX2 inhibitor. Techniques utilized were Enzyme-Linked Immunosorbent Assay …

Design Of Kappa Opioid Receptor Agonists For Potential Treatment Of Multiple Sclerosis, Lindsay Kornberger

Theses and Dissertations--Pharmacy

Multiple Sclerosis (MS) is a neurodegenerative disease of the central nervous system characterized by demyelination and neuroinflammation. There is currently no cure for MS. There is a critically unmet need for the development of pharmacotherapies that can induce remyelination promoting both repair and recovery. The kappa opioid receptor (KOR) has been identified as a potential target for the development of remyelinating pharmacotherapies. KOR activation has been shown to promote functional recovery and remyelination preclinically. However, typical KOR agonists like U50,488 have limitations such as sedation and dysphoria limiting their use. This necessitates further development of new KOR agonists that maintain …

Sensitizing Keap1 Loss Non-Small Cell Lung Cancer To Artesunate Anti-Cancer Activity, Keng Hee Peh

Theses and Dissertations--Pharmacy

Lung cancer is the global leading cause of cancer related death. Non-small cell lung cancer (NSCLC) accounts for 80% of lung cancer diagnoses conferring a significant disease burden. However, certain mutations in tumor suppressors such as Kelch-like ECH-associated protein 1 (KEAP1) confers resistance to standard of care therapy in NSCLC. KEAP1 is known to regulate multiple cellular processes such as oxidative stress response and anti-apoptotic pathways. Furthermore, KEAP1 loss of function in NSCLC is associated with poorer clinical outcomes and there are no currently approved therapies for KEAP1 loss NSCLC and represents an unmet clinical need. Artesunate (Art) demonstrated anti-cancer …

Two Essays On Asset Management, Quan Qi

Theses and Dissertations--Business Administration

My first chapter shows that disruptions in derivative markets can propagate to corporate bond markets via mutual funds that hold both fixed-income securities and derivatives. The transmission arises because when fund managers incur losses in their derivative investments, they are obligated to deliver cash payments to counterparties or provide additional cash collateral to meet margin calls. Using the Covid-19 crisis as an adverse shock on derivative investments bond funds made in 2019 Q4, I find that funds with substantial exposure to derivative market disruptions liquidate fixed-income assets to fulfill corresponding payment obligations. The forced liquidations cause sizable price depressions in …

Autonomous Shuttle Car Docking To A Continuous Miner Using Rgb-Depth Imagery, Sky Rose

Theses and Dissertations--Mining Engineering

A great deal of research is currently being conducted in automating mining equipment to improve worker health and safety and increase mine productivity. Significant progress has been made in some applications, e.g., autonomous haul trucks for surface mining. However, little progress has been made in autonomous face haulage in underground room-and pillar coal mines. Accordingly, this thesis addresses automating the operation of a shuttle car, focusing on positioning the shuttle car under the continuous miner coal-discharge conveyor during cutting and loading operations. The approach uses a stereo depth camera as the sensor, and machine-learning algorithms are used to identify various …

Discrete Element Modeling To Predict Muckpile Profiles From Cast Blasting, Russell Lamont

Theses and Dissertations--Mining Engineering

Movement of overburden or ore from one location to another may be considered the primary physical process of mining. The means by which it is transported is then of primary concern both to economic production and cost control. The geologic characteristics of some mineral deposits, especially coal and phosphates, lend themselves to overburden transport by means of cast blasting, which when efficiently designed has proven itself to be a cheaper method than traditional truck/shovel, dragline, or even dozer push transport. Simultaneously, this movement of a significant portion of overburden using explosives may enable an operation to increase mineral production, as …

Prediction Of Final Subsidence Under Dipping Seam Conditions, Ernesto Maldonado Esguerra

Theses and Dissertations--Mining Engineering

The prediction of ground movements due to underground coal mining and their impacts on the surface are essential considerations that numerous researchers worldwide have studied. Most of these studies have focused on developing different analytical and empirical models for predicting and calculating ground deformation indices for flat or gently dipping seams under variable topography. However, a few studies are available on predicting ground movements under dipping seam conditions. Although most inclined coal seams are in China, India, and a few other countries, dipping seam conditions have been encountered in some cases in the US, where the inclination (dip) may be …

The Determination Of Darcy Permeabilities And Slip Parameters In Porous Thermal Protection Media Via Pressure-Driven Steady Flows At Varying Levels Of Thermal Decomposition, John Ryan O'Nan

Theses and Dissertations--Mechanical and Aerospace Engineering

A flow apparatus for determining the Darcy permeability and Klinkenberg molecular slip adjustment parameter in arbitrary porous media was created. Two leak-proof methods were developed to secure samples of porous media in the flow apparatus independent of surface irregularities, structural integrity, or material porosity. The first of these methods uses thermoset resin casting to permit material samples of a highly irregular profile to be studied. The second method utilizes heat-shrink polyolefin tubing to create a wall seal while preserving the exposed faces of a given cylindrical sample, enabling the study of inhomogeneous surface features. These methods were used to characterize …

Transfer Learning-Enhanced Transformer For Virtual Sensing Applications In Resistance Spot Welding, Ethan York

Theses and Dissertations--Mechanical and Aerospace Engineering

Resistance spot welding is a crucial manufacturing process used across a wide range of industries for permanently joining metal components. Characterized by its applications in the automotive industry, resistance spot welding is valued for its speed, efficiency, and relatively low cost to set up and maintain. The process involves running a pulse of electrical current through two metal sheets to liquify the material and create a permanent bond. The process complexity necessitates precise control over various parameters to ensure acceptable results, emphasizing the importance of quality control. Because there are no low-cost and non-invasive techniques to inspect welds, strategies utilizing …

Propagation Of Vibro-Acoustic Energy In Ducts: Measurement, Simulation, And Attenuation Studies, Caoyang Li

Theses and Dissertations--Mechanical and Aerospace Engineering

Vibro-acoustic energy propagates through heating, ventilating, and air conditioning (HVAC) systems through both airborne and structureborne paths. In this research, measurement and simulation studies are performed to better understand this propagation of energy and how to better attenuate the sound before it impacts building occupants.

First, a scaled-down experiment was developed to assist in the validation of numerical simulation models. A small source room was attached to a wooden duct with variable cross-sectional area. The sound power for both untreated and treated ductwork was measured using sound intensity scanning, and the insertion loss is the difference between untreated and treated …

Artificial Intelligence Enabled Machinery Fault Detection And Diagnosis Using Vibro-Acoustic Signals, Srinivasa Rao Ippili

Theses and Dissertations--Mechanical and Aerospace Engineering

In various industries, the early detection of faults in rotating machinery is crucial to prevent system failures and ensure customer satisfaction. Typically, vibration measurement and diagnosis are employed for fault detection, but this process faces challenges in automation due to the complexity of installing and maintaining accelerometers, particularly in end-of-line quality control or pre-installed machinery health assessments. Acoustic signals, as a form of mechanical wave, offer an alternative for monitoring machinery while in operation. Unlike accelerometers, acoustic transducers are non-contact and easy to set up, enabling real-time data collection without interrupting equipment operation. However, utilizing acoustic signals in manufacturing poses …

Characterization Of The Spallation Phenomenon In Ablative Thermal Protection System Materials Resulting From Arc-Jet Experiments, Kristen Price

Theses and Dissertations--Mechanical and Aerospace Engineering

Thermal protection systems are critical for protecting spacecraft from the large amounts of heating incurred during atmospheric entry. Ablative thermal protection systems in particular often consist of a carbon fiber matrix impregnated with a polymer resin and use thermal and chemical reactions to decompose the material. Weakening of these carbon fibers by oxidation, along with the impact of shear forces, results in the mechanical failure of these materials in a process known as spallation. Being able to quantify and characterize this process is important for modeling and designing heat shield materials that account for the additional spalled mass loss.

Two …

Droplet Analysis Of Spray Inside A Compact Column Gas Scrubber Through Shadowgraphy, Brandon Heller

Theses and Dissertations--Mechanical and Aerospace Engineering

The shadowgraphy imaging technique was adapted to analyze the droplet field from a spray nozzle inside the gas absorption section of a compact column gas scrubber. This technique in conjunction with a developed image processing technique was able to gain statistical size information at different distances from two types of spray nozzles. The gas scrubber then ran a parametric campaign of eight operating conditions and statistical size information was captured for each case with the goal of understanding how operating conditions affect the droplet field properties. Lastly, several simulations were completed to understand how the addition of recirculation zones would …

High-Fidelity Coupling For Studies Of Ablative Materials At Hypersonic Conditions, Aleksander Zibitsker

Theses and Dissertations--Mechanical and Aerospace Engineering

The development of accurate models and robust numerical tools for simulating ablative thermal protection materials (TPMs) in hypersonic flows is crucial for advancing atmospheric entry and hypersonic technologies. Traditional methods for simulating ablative materials often rely on heavy assumptions, such as equal heat and mass transfer coefficients and chemical equilibrium in the boundary layer, leading to conservative thermal protection system (TPS) designs and insufficient accuracy for certain in-flight ablation phenomena.

This work presents a high-fidelity and versatile coupled framework between hypersonic flow and material response solvers. The flow domain is modeled with an innovative overset CHAMPS NBS-Cart solver, which features …

Characterization Of Heterogeneous Material Architectures Through X-Ray Computed Micro-Tomography, Cameron Brewer

Theses and Dissertations--Mechanical and Aerospace Engineering

Low-density carbon-phenolic composites, such as phenolic impregnated carbon ablator (PICA), possess meso-, micro-, and nano-pores making the structure of the resin difficult to characterize. X-ray Computed Tomography (XRCT) is a widely ac- cepted method for characterizing the carbon fiber preform, yet this technique is often insufficient for visualizing the resin because of its minimal attenuation of the incident x-ray beam. Phase Contrast Retrieval (PCR) reconstruction considers not only the linear attenuation coefficient, but also the refractive indices of the constituent materials. This research leverages phase contrast tomography to characterize the meso- and micro-structure of the porous resin phase with a …

Evaluation Of The Cellular And Physiologic Impact Of Mitomycin C On Colon Cancer, Hannah Mcdonald

Theses and Dissertations--Clinical and Translational Science

Cytoreductive surgery (CRS) and heated intraperitoneal chemotherapy (HIPEC) with Mitomycin C (MMC) has more than doubled the overall and disease-free survival in patients with peritoneal metastases (PM) due to colorectal cancer (CRC) over the past two decades. Although MMC is the most used HIPEC drug for PM due to CRC, dosing protocols vary dramatically between and within institutions across the world. Additionally, little is known about the impact of hyperthermia and MMC on intracellular pathways for CRC. The aim of this work is to determine the optimal dosing strategy in the clinical application of MMC and hyperthermia for treatment of …

Advancing Dysphagia Screening: A Comparison Of Patient-Reported Outcome Measures And Bolus-Driven Screenings In Aspiration Prediction, Arica Amie Rusco

Theses and Dissertations--Communication Sciences and Disorders

It is known that dysphagia impacts an individual’s health and quality of life. Due to this, early identification of dysphagia is crucial. There are many different dysphagia screening tools with no consensus. This study aimed to compare the two most frequently used dysphagia screenings, a patient-reported outcome measure (PROM), the EAT-10, and bolus-driven swallow screening, the Yale Swallow Protocol, to determine if one tool is superior in aspiration prediction on a videofluoroscopic swallow study (VFSS). This study also aimed to discover the best cutoff score on the EAT-10 for aspiration prediction. A total of 66 participants were recruited after physician …

The Critical Need For Early Language Access For Deaf And Hard Of Hearing Children, Kinya D. Embry-Wright

Theses and Dissertations--Rehabilitation Sciences

According to the American Speech-Language-Hearing Association (ASHA), speech-language pathologists (SLPs) are referred to as the experts of communication (ASHA, n.d.) utilizing their specialized training, extensive education, and clinical expertise to work with individuals across the lifespan with a variety of different speech and language delays, disorders, and deficits. However, when working with deaf or hard of hearing (DHH) children, there is often precedent given to speech and listening (M. L. Hall et al., 2019). For example, ASHA only recently updated their DHH portal to include American Sign Language (ASL), though they still list it on some webpages as an Augmentative …

Mitigating Risks For Dementia In Apoe4 Mice: Efficacy Of Prebiotic Inulin, Probiotics, And Fecal Microbiota Transplants, Ya-Hsuan Chang

Theses and Dissertations--Pharmacology and Nutritional Sciences

Apolipoprotein E4 allele (APOE4) carriers show early metabolic changes, heightening the genetic risk of late-onset Alzheimer's Disease (AD), characterized by amyloid-β and tau tangle plaques and neurodegeneration. Its development is influenced by age, environment, and genetics, with Mild Cognitive Impairment (MCI) often preceding AD, providing a crucial window for early intervention. Factors in AD progression include sex differences and gut microbiome imbalances, with women disproportionately affected and APOE4 carriers showing early metabolic and cognitive changes. This study explores the potential of prebiotic inulin, probiotic Bifidobacterium animalis, and fecal microbiota transplants (FMT) from healthy donors to mitigate AD …

Practical Challenges In Delivering Dsrna For Woody Plant Protection, Zachary Bragg

Theses and Dissertations--Entomology

Unprecedented weather events associated with climate change, coupled with extensive anthropogenic stresses, have reduced the effectiveness of traditional forest pest management approaches, which can no longer keep pace with invasive species overwhelming naïve landscapes and native pests experiencing eruptive and expansive outbreaks. Double-stranded RNA-(dsRNA) mediated gene silencing, a type of RNA interference (RNAi), has been coopted for use as a biopesticide against a multitude of agricultural and horticultural pests and could serve as a powerful tool for woody plant protection. While effective initiation of gene silencing and subsequent mortality have been demonstrated in multiple tree pests, effective and efficient methods …

Increased Social Support And Maintained Weight Loss Among Post Metabolic And Bariatric Surgery Patients Following A Support And Nutrition-Based Program, Sydney Mae Mcintosh

Theses and Dissertations--Nutrition and Food Systems

Obesity, a prevalent health condition nationwide, has now been recognized as a diagnosable chronic health disease. With that prevalence we have seen a rise in obesity-related comorbidities which can be attributed to excess weight. Therefore, to combat obesity and related comorbidities, metabolic and bariatric surgery is becoming a more accepted and utilized treatment for individuals with obesity. Metabolic and bariatric surgery is the most effective and safest treatment for weight loss in individuals with obesity. However, metabolic, and bariatric surgery is a restrictive and/or malabsorptive procedure that requires significant lifestyle changes before and after the procedure. Patients who undergo metabolic …