Digital Commons Network^™

Engineering A Novel Solvent Regenerator That Leverages Electrochemically Induced Ph Swings For Direct Air Capture And Hydrogen Generation, Emmanuel Aluhunmile Ohiomoba

Theses and Dissertations--Mechanical and Aerospace Engineering

Direct Air Capture (DAC) is considered to be a key component for achieving global net-negative emissions. However, to capture CO₂ at the low concentrations in the atmosphere requires materials with high affinity for CO₂. This makes the solvent-based chemical approach for DAC more applicable compared to physical approaches. Nonetheless, regenerating the capture solvent presents a significant challenge due to high heat requirements for thermal decomposition of carbonates. Leveraging electrochemical principles provides an opportunity to simplify the regeneration process, thus, this work focuses on engineering an electrochemical solvent regenerator for recovering alkaline solvents for DAC, with co-production of …

Machining-Induced Residual Stress Modeling Using Physics-Informed Neural Networks, Md Mehedi Hasan

Theses and Dissertations--Mechanical and Aerospace Engineering

Process-induced residual stress (RS) plays a critical role in determining the structural integrity, fatigue life, corrosion resistance, and dimensional stability of manufactured components. Tensile residual stress can be harmful to the machined workpiece by lowering fatigue strength, while compressive residual stress helps to prevent such issues. Therefore, accurate prediction and control of machining-induced residual stresses are essential for optimizing manufacturing processes and enhancing component performance. However, existing modeling approaches—empirical, analytical, and numerical—often have limited predictive accuracy, demand extensive calibration, or involve high computational costs. Traditional finite element analysis (FEA) provides modeling insights but is constrained by its high computational cost …

Development Of An Immersed Boundary Method-Wall Modeled Large Eddy Simulation Approach For Incompressible Flows And Aeroacoustic Predictions, John C. Higgins

Theses and Dissertations--Mechanical and Aerospace Engineering

The performance capabilities of rotorcraft have improved significantly in the past decade as both manned and unmanned rotorcraft become a larger part of future transportation systems. Private companies as well as various government offices have worked to develop capabilities ranging from transportation/package delivery to intelligence/surveillance to livestock monitoring. Their practicality in both rural and urban areas, however, is questionable due to the significant tonal and broadband noise which is produced by the rotors. Public acceptance of rotorcraft, namely small Unmanned Aerial Vehicles (sUAVs), in transportation systems is an issue largely associated with the noise generation and it's effect on nearby …

High-Altitude Balloon-Launched Uncrewed Aircraft System Measurements Of Atmospheric Turbulence And Qualitative Comparison With Infrasound Microphone Response, Anisa Haghighi

Theses and Dissertations--Mechanical and Aerospace Engineering

This study explores the use of a balloon-launched uncrewed aircraft system (UAS) to measure atmospheric turbulence in the troposphere and lower stratosphere using both wind velocity measurements and infrasonic acoustic energy. The UAS, a glider configured for autonomous descent along a predefined trajectory, had on board, in situ sensors to capture thermodynamic and kinematic atmospheric parameters. Additionally, it carried an infrasonic microphone to evaluate its potential for remotely detecting clear-air turbulence by capturing infrasonic waves. The system’s performance was assessed over the course of three test flights conducted in New Mexico, USA, in 2021. The descent enabled high-resolution profiling, with …

Kentucky Re-Entry Universal Payload System (Krups): Second Atmospheric Re-Entry Flight, Kirsten F. Ford

Theses and Dissertations--Mechanical and Aerospace Engineering

Kentucky Re-entry Universal Payload System (KRUPS) is a small-scale re-entry capsule developed at the University of Kentucky. The KRUPS project began in 2013 with the aspiration of providing an affordable and repeatable method of collecting data on the re-entry environment. Numerically-based methods used to model re-entry require experimental data to validate their predictions. However, re-entry data is not easily obtained. Flight tests of re-entry vehicles require extensive time and resources, including a substantial financial burden. Alternatively, ground testing is not able to accurately and completely replicate the complex re-entry environment. Thus, there is a need for an inexpensive and accessible …

Cultivating Hegemony: Cultural Engineering And The Art Of Power Maintenance In Military Movies, Samuel Lockridge

Theses and Dissertations--Arts Administration

This research explores how the United States military’s assistance to film productions can be better classified and understood as a form of cultural policy. There is a significant gap in the existing cultural policy research concerning interventions into the arts and culture by the military aimed at influencing the thoughts, beliefs, and attitudes of the population. The degree to which the U.S. Department of Defense’s (DoD) long partnership with the film industry should even be considered “cultural policy” remains an open, and largely unexamined question. This dissertation presents an exploratory multiple case study of two films which received DoD production …

The Dying Swan: How To Predict And Evaluate The Survival Rate And Longevity Of Small Dance Companies In The United States, Evemarie N. Bessenbach

Theses and Dissertations--Arts Administration

Smaller dance organizations are an integral component of the arts and culture sector in the United States, making valuable artistic, economic, and social contributions despite limited resources. They provide employment for professional artists, contribute to a region’s economic vitality, and increase accessibility to quality arts-related programming. However, there are numerous professional dance companies that have permanently closed these past ten years alone, such as Dance Theatre of Tennessee, Ballet Theatre of Indiana, and Missouri Ballet Theatre, to just name a few—all of which can be considered smaller dance organizations.

The purpose of this interdisciplinary, exploratory study is to address the …

Come Hell Or High Water: A Constructed Grounded Theory Of Disaster Preparedness In Nonprofit Arts Management, Leah D. Hamilton

Theses and Dissertations--Arts Administration

This dissertation study constructs a grounded theory of disaster preparedness in nonprofit arts management, a research area that is underrepresented in broader disaster science research, and underrecognized by US government emergency management policy. Using the Constructivist Grounded Theory methodology, this qualitative study involves a systematic document review of more than 20 years of US practices and standards related to arts preparedness in combination with a two-year inquiry using a purposive sample of nonprofit arts managers who have recently been affected, directly or indirectly, by disasters in the state of Kentucky. The findings and the subsequent Theory of Performative Preparedness provide …

Early Adversity, Impulsivity, And Health Behaviors, Amy Lynn Meadows

Theses and Dissertations--Clinical and Translational Science

Childhood trauma and early adversity are associated with a variety of negative health outcomes, some of which may be mediated by changes to impulsivity as described by the cumulative risk model. The purpose of this project is to provide insight into the effects of cumulative adverse childhood experience on impulsivity in various populations. Three studies examine the effects of early adversity on impulsivity in normal volunteers, parents caring for a child with medical needs, and in patients with diabetes or pre-diabetes with data collected through crowdsourcing. The strongest effects for early adversity on impulsivity were seen in the patients with …

Enhancing Public Health Surveillance: Development And Validation Of Machine Learning Models For Suspected Opioid Overdose Detection In Emergency Medical Services Data, Peter J. Rock

Theses and Dissertations--Clinical and Translational Science

The ongoing opioid overdose crisis in the United States requires timely and accurate surveillance systems to inform public health responses. Traditional public health surveillance methods rely on hospital discharge data and death certificates, which suffer from significant reporting delays and miss cases where patients refuse hospital transportation. Emergency Medical Services (EMS) data presents a promising alternative with advantages in timeliness and case ascertainment but lacks validated definitions for suspected opioid overdose (SOO).

This dissertation addresses this critical gap through the development, validation, and fairness assessment of machine learning models with natural language processing (ML-NLP) for identifying SOOs in EMS data. …

Exploring Healthcare Access In Telehealth Through Spanish-Speaking Patients’ Perspectives: A Scoping Review, Abigail J. Verst

Theses and Dissertations--Communication Sciences and Disorders

Background: Telehealth offers a potential solution to addressing access barriers experienced by Spanish-speaking patients. This scoping review aimed to explore whether a comprehensive view of healthcare access is being considered when creating telehealth programs for Spanish-speakers. The Conceptual Framework of Access to Healthcare (Levesque et al., 2013) was used to guide access analysis.

Methods: A literature search was conducted across three databases to identify empirical studies in the United States that reported Spanish-speaking patients’ perspectives of telehealth through quantitative questions. Data was collected from the included articles to characterize the type of healthcare providers and telehealth modalities examined in the …

Holding Space For Two Truths: Thematic Analysis Of Speech Language Pathologists’ And Teachers’ Philosophies And Practices In Reading Comprehension, Ryan Foote

Theses and Dissertations--Communication Sciences and Disorders

Introduction: Reading is a doorway to life participation. Only about one-third of fourth graders have read at grade level for the last three decades. Multiple views on what constitutes skilled reading emphasize decoding and greater variability among comprehension-related skills. Scarborough’s Reading Rope is the most specific in defining discrete skills necessary for adequate reading comprehension. This study aims to understand how elementary-level general education teachers and speech-language pathologists define “reading comprehension” and describe their practices in assessing and developing these skills. Methodology: Elementary school speech-language pathologists and teachers were interviewed about their conceptualizations and applications of the discrete skills in …

M1 Macrophage-Engineered Vesicles Have Anti-Cancer Activity In Ovarian Cancer, Connie Du Cao

Theses and Dissertations--Clinical and Translational Science

Ovarian cancer typically presents at an advanced stage, has a poor prognosis, and is a leading cause of cancer-related deaths in women. Extracellular vesicles (EVs) are cell-derived membrane-bound nanoparticles that function in specific cell-to-cell communication and are under development as novel drug delivery vehicles and modulators of the tumor microenvironment. Artificial cell-derived vesicles (ACDVs) derived from M1 macrophages are able to repolarize M2 macrophages to the M1 phenotype and target tumor cells in in vitro studies.

In this study, we generated engineered EVs (EEVs) by membrane disruption of M1 macrophages (MEVs) in the presence and absence of cisplatin to generate …

Zebrafish Models To Uncover Targetable Mechanisms Of Self-Renewal In T-Cell Acute Lymphoblastic Leukemia, Majd Al-Hamaly

Theses and Dissertations--Pharmacology and Nutritional Sciences

Relapsed T-cell Acute Lymphoblastic Leukemia (T-ALL) patients have dismal prognosis, with 5-year overall survival rates of 10% for adults and 36% for children. Relapse is attributed to the inability of chemotherapy agents to eliminate Leukemia Stem Cells (LSCs) that can repopulate the leukemia. Those cells exist with a unique genetic, transcriptomic, and metabolic profile compared to the rest of the leukemia and thus, finding targeted therapies toward this population of cells can result in disease eradication and elimination of relapse. However, investigating LSCs is challenging-particularly in T-ALL- for two reasons: 1) the lack of robust surface markers that define LSCs …

Cell-Type Specific Apoe4 To Apoe2 ‘Switching’ In Astrocytes And Microglia Alters Alzheimer’S Disease Neuropathology, Lesley R. Golden

Theses and Dissertations--Physiology

Apolipoprotein E (APOE) is the strongest genetic risk factor for late-onset Alzheimer’s disease (LOAD). APOE exists in three common protein isoforms throughout the population: ApoE2 (E2), ApoE3 (E3), and ApoE4 (E4). While APOE allele frequencies and the degree of AD-associated risk vary across different ethnic groups, when compared to the ‘neutral’ and most common E3 allele, the E4 allele confers up to a 33-fold increase in Alzheimer’s Disease (AD) risk. Conversely, the neuroprotective E2 allele decreases AD risk by up to 67%. Here, we aimed to determine the therapeutic potential of cell-type specific APOE allele ‘switching’ and explore …

Biochemical Properties Of Cardiac Sarcomeres In Human Heart Failure, Austin Grey Wellette-Hunsucker

Theses and Dissertations--Physiology

Heart failure (HF) exhibits considerable heterogeneity, posing significant challenges for research involving human cohorts. Diastolic dysfunction is a common pathophysiological feature; however, its molecular mechanisms remain incompletely elucidated. Sarcomeric proteins are integral to cardiac contraction and relaxation. Nonetheless, the phosphoproteome and the structural remodeling effects of these proteins on diastolic function within the context of HF have not been comprehensively characterized. This study examined sarcomeric modifications in diastolic dysfunction in human HF, focusing on Dilated and Ischemic HF, with non-failing donor hearts as controls. Analyzing myocardial samples from ~150 patients using electrophoretic and biochemical techniques, it found significant titin remodeling …

Assessing The Effectiveness Of A Modified Cook Together Eat Together Program On Food Resource Management Behaviors In A Rural Setting, Johanna K. Poysti

Theses and Dissertations--Nutrition and Food Systems

This study evaluated the effectiveness of a modified, hybrid Cook Together, Eat Together (CTET) program on food resource management behaviors in a rural setting. A six-week intervention combining virtual and in-person sessions aimed to improve health behaviors, food resource management skills, and self-efficacy. Although most behavioral changes were not statistically significant, participants reported increased confidence in cooking healthy meals on a budget. Positive qualitative feedback from focus group discussions indicated program feasibility and engagement. Strengths and limitations of the study were discussed as well as recommendations for future research were given.

Bed Bugs: Health Risks And Control, Simona Principato

Theses and Dissertations--Entomology

Bed bugs are blood-feeding hemipterans strongly associated with humans. Their detection in indoor environments, such as homes, hotels, trains, and public facilities, has increased gradually over the past 20 years. The exact cause of their resurgence is still unclear, but the increase of international travel and insecticide resistance are thought to have contributed to it.

Although bed bugs are not known to transmit diseases, the EPA, CDC, and USDA have classified them as a pest of significant public health concern, mainly due to the dermatitis that they can cause. Beyond the dermatological burden of the bites, other health implications often …

Family And Social Factors In Emotion Regulation And Adjustment In Adolescents, Julia J. Morgan

Theses and Dissertations--Family Sciences

Adolescents face many challenges during this unique phase of development. Because of this, it is important to identify how to promote resilience and positive adjustment for these individuals. The present dissertation includes three studies which focused on familial and social factors in promoting emotion regulation and ultimately adjustment among middle and late adolescents.

The first study focused on the importance of alexithymia in the relationships between closeness and communication and internalizing problems, namely depression, anxiety, and self-esteem. Results showed that closeness was negatively associated with depression and positively associated with self-esteem. Communication was not associated with any of the studied …

Childhood Chronic Illness: Assessing Emerging Adults’ Engagement In Social Activities And Predicted Money For Comfort In The Future, Mediated By Money Responsibility And Comparison To Others, Austin B. Mathews

Theses and Dissertations--Family Sciences

The purpose of this study is to examine the relationships between emerging adults’ engagement in social activities and their prediction of having money for comfort in the future. Data used was from the Panel Study of Income Dynamics (PSID) with individuals selected having at least one chronic illness that began during childhood. The study tested a series of hypothesis which tested the relationships between engagement in social activities and predicted money for comfort in the future, as well as, money responsibility and comparison to others as mediating variables. Significant associations were found between frequency of engagement in sports and money …

Debt Through The Decade: Exploring Connections Between Debt Type, Psychological Stress, Spending Habits, And Life Satisfaction, Emily Johnson

Theses and Dissertations--Family Sciences

Average households in the United States holds $101,915 in consumer debt, contributing to the greater total of America’s $17.3 trillion of total consumer debt (Experian, 2024). Accruing some amount of debt is considered normal throughout a financial lifespan, however, many Americans find themselves completely overwhelmed by keeping up with personal debts and increasing costs of necessities due to inflation. (George & Hansen, 2018; Kim et al., 2019). Following the financial crisis in 2020, many individuals felt increasing financial hardship, with many Americans heavily impacted by their debt holdings. The purpose of the present study is to examine the impact of …

The Role Of Nutrition In Managing Honey Bee Viral Pathogen, Caroline Wylie Kane

Theses and Dissertations--Entomology

This study evaluated the impact of nutritional supplements on viral infections in honey bee colonies, focusing on Lake Sinai Virus 2 (LSV2), Deformed Wing Virus A (DWVA), and Deformed Wing Virus B (DWVB). I partnered with 32 hobbyist beekeepers across Kentucky, who volunteered 138 colonies for a month-long field study. Half of the colonies received weekly commercial supplements, while the other half served as controls. Viral titers were measured before and after the supplementation period using qPCR. Supplements did not significantly reduce viral titers for any of the three viruses, suggesting that short-term supplementation may not be effective in lowering …

Exportin 1 Is The Central Hub In Antiviral Defensive Mobilization Of Nuclear Factors And The Target Of Counter-Defence By Tombusviruses, Biao Sun Dr.

Theses and Dissertations--Plant Pathology

Positive-strand RNA viruses, such as coronaviruses and flaviviruses, are obligate parasites whose genomic RNAs function as mRNAs. These viruses infect a wide range of hosts-including plants, animals, and humans-resulting in significant economic losses and posing serious threats to public health. Due to the relatively simple structure of the genome of positive-strand RNA viruses, many host factors and physiological processes are co-opted to support virus infection and replication. In our previous studies, we identified numerous host factors and associated physiological processes involved in the replication of tombusviruses, a cytosolic-replicating model that includes tomato bushy stunt virus (TBSV) and carnation Italian ringspot …

Gene Expression In Relation To Bone Fractures In Throughbred Racehorses, Anna M. Rauber-Ramos

Theses and Dissertations--Veterinary Science

Evidence that fractures in Thoroughbred racehorses are outcomes of chronic bone microdamage has led to extensive research into identifying horses at increased risk of fracture. This includes the use of biomarkers and messenger RNA (mRNA) as a measure of bone turnover. Previous research has found expression differences in horses with fractures compared to controls. Utilizing pre-race whole blood samples collected over an 18-month period from Thoroughbred racehorses in Southern California, RNA-sequencing was conducted on horses with bone fractures and race-matched controls to identify differences in gene expression. Focusing on third metacarpal (MC3) and proximal sesamoid bone (PSB) fractures, differentially expressed …

Avian Response To Legacy Coal Mine Reforestation In The Cumberland Plateau, Kentucky, Madoline J. Varias

Theses and Dissertations--Forestry and Natural Resources

Surface coal mining and reclamation processes alter the ecological characteristics of landscapes, which affects the presence and distribution of native wildlife. The Forestry Reclamation Approach (FRA) is a coal mine reclamation method that aims to establish native forests on surface mines and has been widely implemented across the Central Appalachian region. Avian response the FRA, in particular, is unknown in Kentucky and limited throughout Appalachia. Thus, the goal of this project was to assess the effects of the FRA on avian community occupancy, species richness, and abundance in the Cumberland Plateau of Kentucky. Point count surveys were conducted across three …

Predicting Patterns Of Species Presence In Eastern Kentucky Using Fine- And Broad-Scale Site-Species Relationships, Kyra L. Shrout

Theses and Dissertations--Forestry and Natural Resources

Understanding site-species relationships is integral to effective forest management, as landscape factors influence both the presence of mature trees and the regeneration of future trees. This study examined the influence of topographic, soil, and canopy variables on species presence at both fine (i.e., stand-level) and broad (i.e., forest-wide) scales within Robinson Forest, Kentucky. At the fine-scale, using vegetation data from permanent sampling plots, LiDAR-derived topographic data, and historical soils data, the relationships between the species of interest and the landscape variables within a single watershed were analyzed using conditional inference tree (CTree) models. Elevation and slope aspect were the most …

Mapping The Impact Of Leadership Training: A Ripple Effects Mapping Of The Kentucky Extension Homemaker Association’S First Leadership Academy, Kelly May

Theses and Dissertations--Community & Leadership Development

This research study evaluates the first Kentucky Extension Homemaker Association (KEHA) Leadership Academy using the participatory, qualitative evaluation tool Ripple Effects Mapping (REM). This study explored the impact and outcomes of the training, both intended and unintended.

REM is a participatory evaluation method that begins with appreciative inquiry, then continues with a group discussion where stories are “mapped” or illustrated in real time. Using the Theming and Rippling Method of REM, the research team coded the information on site with inductive theming and those themes were then shared and confirmed with the group. After the event, the mapped data was …

Researching Dementia Indicators Among Rural Populations, Justin S. Yount

Theses and Dissertations--Community & Leadership Development

The study explored potential dementia indicators and risk factors among older adults residing in rural areas who are actively engaged in farming operations. Data was collected in three components a questionnaire, an audiogram test, and a memory impairment screening. 104 people responded to the questionnaire, 133 participants took the audiogram test, and 94 participated in the memory impairment screening. The findings revealed that 80.9% of participants showed no sign of cognitive impairment while 19.1% showed signs of possible impairment. Participants reported moderate levels of physical and social activity, but common risk factors such as elevated BMI, diabetes, hearing loss, and …

Influence Of Agrochemical Mixtures On Nitrogen Transformations In Floating Treatment Wetlands, Matthew Russell

Theses and Dissertations--Biosystems and Agricultural Engineering

Controlling losses of nitrate-N from agricultural fields to ground and surface water environments is one of the most pressing water resources problems today. Increasing levels of nitrate-N pollution in surface and groundwater is a critical threat to human and environmental health across the globe. To mediate nitrate-N losses, natural and constructed wetlands have been increasingly used as nutrient mitigation technologies and strategies. The use of wetlands as a treatment approach for nitrogen in runoff is a common practice in agroecosystems, however, nitrate-N is not the sole constituent present in agricultural runoff, and other biologically active contaminants have the potential to …

Nanopesticide Fate And Transport In Agroecosystems: A Field Study, John C. Stickney

Theses and Dissertations--Biosystems and Agricultural Engineering

Nanopesticides are an emerging class of pesticides associated with engineered nanoparticles that provide agricultural and environmental benefits. However, nanopesticide fate, transport, and persistence remain poorly understood. As do their potential impacts on the health of agroecosystems and influence on nutrient release. Therefore, this project investigated the fate, transport, and persistence of two widely available nanopesticides, an insecticide, nano-imidacloprid, and a fungicide, nano-copper hydroxide. The fate and transport in runoff water and soils of these nanopesticides, as well as their impacts on nutrients retention, were assessed through a field plot study over 2 growing seasons. Runoff from rainfall events and soil …