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Health Beliefs, Facilitators And Barriers To Engaging In Blood Glucose Screening Of Adults In Saudi Arabia, Fatema Alsada

Theses and Dissertations--Nursing

Diabetes has reached an epidemic level in Saudi Arabia with a prevalence of 19%. Saudi Arabia currently spends more than $7 billion on diabetes-related health care per year. Type 2 diabetes is preceded by a prediabetes state during which preventative measures can prevent or delay diabetes onset. Blood glucose screening is a method of identifying people with prediabetes. Encouraging people to engage in blood glucose screening will identify those who will benefit from diabetes prevention strategies. The purpose of this dissertation was to explore the knowledge, health beliefs, and perceived barriers and facilitators regarding engaging in blood glucose screenings among …

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 …

Inhibiting Pi3k/Akt To Enhance Brain Uptake Of Anticancer Agents In Glioblastoma, Louis Rodgers

Theses and Dissertations--Pharmacy

Glioblastoma (GBM) is the deadliest and most common malignant CNS tumor. Despite advances in understanding its biology and the development of targeted therapies, effective treatment options remain limited. As a result, patient survival rates are dismal, with a 5-year survival rate of only 6.8% and an overall survival of less than two years. This poor outcome is partly due to our inability to treat GBM cells that infiltrate the whole brain. Focal treatments like surgery and radiotherapy alone are insufficient due to these invasive tumor cells. Therefore, chemotherapy following resection and irradiation of the primary tumor is essential to eliminate …

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 …

The Methodology For Integrating Robotic Systems In Undeground Mining Machines, Peter Kolapo

Theses and Dissertations--Mining Engineering

Roof bolting is a critical operation in ensuring the safety and stability of underground mines by securing the roof strata with bolts. The process involves moving and manipulating heavy tools while being vigilant about the safety of the area. During the installation of roof bolts, operators are exposed to hazardous conditions due to challenging working conditions in underground mines, extensive working hours, and demanding shift schedules leading to personnel fatigue and influencing operators to take shortcuts that may increase the risk of injuries and fatal accidents. The successful completion of roof bolting tasks depends heavily on operator judgment and experience …

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 …

Copper Ammoniacal Recycling Process Development For Leaching Electrolyte, Solvent Extraction, And Electrowinning, Zulqarnain Ahmad Ali

Theses and Dissertations--Mining Engineering

Electronic waste (e-waste) encompasses waste originating from electronic and electrical equipment. In 2022, 59.4 million metric tons of e-waste were generated, projected to increase to 74.7 million metric tons by 2030. Among the most valuable components within E-Waste are the printed circuit boards (PCBs), primarily composed of metals including copper (Cu), gold (Au), silver (Ag), cobalt (Co), nickel (Ni), bismuth (Bi), and various other base and precious metals. Notably, copper is the predominant element in PCBs, with concentrations exceeding those in their respective ores. The high demand for copper driven by the ongoing push towards greener technologies and its abundant …

Characterization And Concentration Of Critical Minerals And Rare Earth Elements From Primary And Secondary Silicate Deposits, Muhammed Melih Elseyh

Theses and Dissertations--Mining Engineering

Critical materials (CMs) are crucial for sustainable energy. This investigation explored the extraction of rare earth elements (REEs) from the Halleck Creek deposit in Wyoming, and CMs from a construction sand deposit in Missouri. The Halleck Creek deposit is REE enriched (0.32%) as the mineral allanite within silicious host rock. Density fractionation tests revealed that 70% of the gangue can be rejected while recovering 90% of the REEs with an upgrading ratio of 4.5:1. By exploiting allanite’s paramagnetic properties, magnetic separations achieved a TREE upgrade ratio of 3:1 with 87% TREE recovery. Based on the density fractionation results, a rougher-scavenger-cleaner …

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 …

Measurement And Simulation Of Aeroacoustic Sources Generated By Elementary Muffler Components, Seth Donkin

Theses and Dissertations--Mechanical and Aerospace Engineering

Mufflers and silencers are commonly used to control noise from sources such as internal combustion engines and heating, ventilating, and air conditioning (HVAC) systems. In these applications, flow interacts with muffler components generating aeroacoustic noise sources. In order to measure these sources in a lab setting, specialized flow rigs are designed to isolate aeroacoustic noise sources. Flow sometimes compromises muffler performance. However, muffler performance is sometimes improved because flow can increase the attenuation of some muffler elements such as perforates. To better understand the complicated impact of flow, the University of Kentucky developed a muffler test rig to measure insertion …

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 …

Microstructure-Based Modeling And Simulation Via A Nonlocal Multiphysics Discrete Approach, Donglai Liu

Theses and Dissertations--Mechanical and Aerospace Engineering

Many structures in engineering are subject to multiphysics loadings or environment. Computational modeling plays a significant role to predict or evaluate the performance of these structures, especially in the scenarios where the experimental investigation is cumbersome or prohibitively expensive. Microstructure-based modeling incorporates the information of microstructures of materials in numerical models, which can provide insights about the relationship between microstructures and mate- rial properties. This research developed a microstructure-based modeling framework for coupling diffusion-deformation simulation of solids. The model is based on a recent developed meshfree method referred to as lattice particle method in the literature. In the developed model, …

Mechanochemical Synthesis Of Halide Perovskite Microcrystals, Xuan Huang

Theses and Dissertations--Mechanical and Aerospace Engineering

Halide perovskites have emerged as a promising class of materials for various optoelectronic applications, including light-emitting diodes (LEDs), solar cells, photodetectors, and lasers, owing to their exceptional photophysical properties and ease of synthesis. Lead-based halide perovskites, despite their success, raise concerns regarding environmental toxicity, necessitating the exploration of lead-free alternatives. This thesis explores the synthesis and characterization of lead-free halide perovskites, focusing on tin-based variants, using a mechanochemical approach, which eliminates the use of toxic solvents and offers a sustainable synthesis route.

By employing a solventless mechanochemical method, lead-free tin-based halide perovskite microcrystals were successfully synthesized. This approach not only …

Provably Safe Control For Input-Constrained Robotic Systems, Pedram Rabiee

Theses and Dissertations--Mechanical and Aerospace Engineering

This dissertation addresses challenges in control design for safety-critical robotic systems with input constraints. It focuses on developing novel control barrier function (CBF) approaches to ensure safety while optimizing performance. The work is motivated by the limitations of traditional methods in handling nonlinear systems with multiple constraints and actuator limits.

Three main contributions are presented. First, a soft-minimum barrier function is introduced, utilizing finite-time horizon predictions to create control forward invariant subsets of the safe set while respecting actuator constraints. This method is extended to multiple backup controls, which can enlarge the safe operating region.

Second, a technique for composing …

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 …

Multiscale Fiber Remodeling In The Heart Using A Finite Element Framework, Mohammad Mehri

Theses and Dissertations--Mechanical and Aerospace Engineering

The organization of myofibers and extra cellular matrix within the myocardium plays a significant role in defining cardiac function. When pathological events occur, such as myocardial infarction (MI) or hypertrophic cardiomyopathy (HCM), this organization can become disrupted, leading to alteration in pumping performance. The current study proposes a multiscale finite element (FE) framework to determine realistic fiber distributions in the left ventricle (LV). This is achieved by implementing a stress-based fiber reorientation law, which seeks to align the fibers with local traction vectors, such that contractile force and load bearing capabilities are maximized. By utilizing the total stress (passive and …

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 …

A Hyphenated Career: Sustainable Pathways For Dancers, Rebecca A. Ferrell

Theses and Dissertations--Arts Administration

Despite the rich cultural and artistic contributions of dancers, there exists a pressing need to comprehensively address the challenges and complexities surrounding the sustainability of careers in dance due to underemployment, underpayment, data undercounting and physical strain. This dissertation research aims to understand occupational trajectories that build a sustainable career for dancers. Through a historical examination of the professionalization of dance and an investigation of current career opportunities, this study investigates the growing support systems for dancers, the influence of occupational identity, and the workplace environments needed to sustain a dance career.

Occupational identity theory, motivation-hygiene theory, and transaction cost …

Three Contemporary Prosecution Case Studies And The Challenges Affecting The Indian Arts And Crafts Act, Tiffini Bowers

Theses and Dissertations--Arts Administration

The Indian Arts and Crafts Act (IACA) is America’s only federal arts policy. This study explores the IACA and the challenges contemporary prosecution cases identify for arts stakeholders, along with the implementation and effectiveness since the 2010 Act, to understand better the social and public policy implications and challenges for arts stakeholders. A qualitative study using multiple legal case studies, document analysis, and semi-structured interviews, along with an elite theory theoretical framework, anchors the research. Findings support existing research by indicating the main challenge is the definition and complexity of Indian identity; additional significant findings that contribute to future policy …

Music For The People: Comparing Public Funding Models For Popular Music In Atlanta, Glasgow, And Toronto, Heather Mcdonald

Theses and Dissertations--Arts Administration

This dissertation explores the complex landscape of public funding policies for popular music across three cities: Atlanta, Glasgow, and Toronto. Through comparative case studies and qualitative research methods, this work explores the varying approaches each city takes towards funding popular music, including the social, economic, and political environments in which these funding policies have developed.

Through document reviews and interviews with key stakeholders, the dissertation highlights the differences in how public funding for popular music is approached in Glasgow, Atlanta, and Toronto and the broader context of how these policies were created. Using Multiple Streams Approach, the Five Streams Confluence …

Orchestra Community Engagement: Factors Of Environmental Impact, Travis Newton

Theses and Dissertations--Arts Administration

The symphony orchestra industry in the United States was founded with the goal of serving the elite, but these orchestras are organized as not-for-profit organizations and are currently mandated to benefit the community more broadly. Professional symphony orchestras in the United States are beginning to address this disconnect between their elite-oriented origins and the more modern federal mandate of community-oriented service in a variety of ways, including through community engagement programming. There are a number of items that remain unknown, including the impact that environmental factors have on orchestras’ community-oriented work, and what “community engagement” means to orchestras.

The purpose …

Repolarizing Tumor-Associated Macrophages In Ovarian Cancer: A Novel Immunotherapeutic Approach, David Schweer

Theses and Dissertations--Clinical and Translational Science

Ovarian cancer, recognized for its high lethality and resistance to conventional immunotherapies, mandates innovative strategies to confront its intricate challenges. The tumor microenvironment (TME), orchestrated by tumor-associated macrophages (TAMs), assumes a pivotal role in disease progression, rendering TAMs an appealing therapeutic target. This study endeavors to explore the prospect of repolarizing TAMs from a protumor M2 phenotype to an antitumor M1 state, employing M1 macrophage-derived vesicles (MEVs) as a groundbreaking immunotherapeutic approach.

The primary objective is to investigate the capacity of M1 MEVs to repolarize M2 macrophages in vitro towards an anti-tumor M1-like phenotype. By inducing human macrophages to adopt …