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Two Network Flow Problems: Volume Inequalities For Flow Polytopes Of Full Directed Acyclic Graphs; Optimal Additions To The Low-Stress Bike Network In Lexington, Kentucky, James F. Mcelroy

Theses and Dissertations--Mathematics

This dissertation addresses two distinct problems related by their foundation in network flows. The first problem concerns volumes of flow polytopes of directed acyclic graphs with out-degree sequence (3,2,...,2,0). It is proved that there is an interchange operation on the edge set of these graphs that induces a partial order on the graphs isomorphic to a Boolean algebra, and that moving up through this partial order decreases (weakly) the volumes of the corresponding flow polytopes. This result is reinterpreted in the context of linear extensions for posets that are bipartite non-crossing trees.

The second problem develops a discrete optimization model …

Applied Essays In Industrial Organization: Pricing In Short-Term Rental Markets And Policy Implications In Tobacco Consumption, Richard J. Applin

Theses and Dissertations--Economics

Economics 101 teaches that the interaction between supply and demand determines the prices and quantities consumers face. In econometric research, it is critical to remain aware of this canonical fact, as failure to do so can introduce bias in the estimation of economic parameters. This dissertation empirically demonstrates the importance of factoring in economic structure in three applied essays.

In the first essay, I estimate the impact of rating visibility on Airbnb pricing using a two-way fixed effects model. To do so, I primarily rely on an instrumental variables approach that I argue should identify a supply-side relationship. I provide …

Three Essays On The Impacts Of Pollution, Isaiah Chapman Bryant Sheth

Theses and Dissertations--Economics

My dissertation is broadly focused on using data to quantify the consequences of pol- lution and is organized into three chapters. Chapter one estimates the effect on infant health of drinking water contamination attributable to tropical cyclones. Chapter two examines the heterogeneous effects of a policy aimed at reducing air pollution based on pre-existing air quality conditions. Lastly, chapter three investigates how regula- tions aimed at shaping housing development to minimize climate risk impacted the housing market in Houston Texas. Each of these chapters considers different con- sequences of pollution, from direct health costs of pollution exposure to secondary effects …

Cellular And Behavioral Consequences Of Psychedelic Drug Action In The Claustrum, Tanner L. Anderson

Theses and Dissertations--Neuroscience

Psychedelics are rapidly garnering research attention for their ability to successfully treat a variety of psychiatric diseases after one or a handful of treatments in recent clinical research. Among the conditions treated is substance use disorder (SUD), which afflicted 48.5 million (16.7%) Americans aged 12 and older in 2023 (NSDUH). As clinical trial results continue to show lasting positive effects of psychedelic psychotherapy, there remains an enormous gap in knowledge regarding how these drugs cause lasting changes in the brain to achieve these therapeutic effects. It has been suggested that psychedelics must induce rapid and long-lasting neuronal plasticity in order …

Leveraging Clinical Standards To Improve The Translational Relevance Of Therapies For Experimental Spinal Cord Injury, Aaron L. Silverstein

Theses and Dissertations--Neuroscience

Efforts to improve treatment of spinal cord injury (SCI) often use animals to develop effective therapeutics, intending to improve the survival and the quality of life of persons with SCI. Over half of all SCIs in the United States occur at the cervical level and often cause locomotor deficits and life-threatening breathing dysfunction. Thus, my dissertation is focused on this important patient population.

After beginning with a description of translational research and surveying SCI from a clinical standpoint, I turned to describe experimental models of cervical SCI and more detailed neuroimmunological findings relevant to my work. Then, I conducted a …

Changes In Cancer Diagnosis And Survival In The United States During The Covid-19 Pandemic, Justin T. Burus

Theses and Dissertations--Epidemiology and Biostatistics

The COVID-19 Pandemic led to global societal disruptions as political leaders and public health authorities attempted to control the spread of the newly discovered SARS- CoV-2 virus. While these measures were designed to lessen morbidity and mortality from a novel pathogen, their impact was also felt in many other, often unintended ways. The purpose of this dissertation is to use cancer surveillance research methods to examine the association between COVID-19 Pandemic-related disruptions and changes in the normal diagnosis and care of cancer in the United States.

The first two studies of this dissertation analyzed reductions in cancer diagnoses in the …

Towards A Sociological Theory Of Consent And Coercion In Sexual Violence Against Women, Lisa Kistler

Theses and Dissertations--Sociology

Recent data estimate that 26.8% of adult women in the U.S. have experienced rape in their lifetime. In this context, the phrase “consent to sex” is a prominent narrative countering sexual violence. Yet, there is no consensus on the meaning of consent, nor how the practice of consent is affected by coercion, resulting in a puzzle of consent. In response, the present project brings together existing research and theory to conceptualize consent and coercion in new ways. It asks, broadly, how do different forms of coercion complicate sexual consent and contribute to sexual violence against women today and answers this …

A Comprehensive Exploration Of Stress And Depressive Symptoms In Farm Populations, Julie C. Derringer

Theses and Dissertations--Nursing

High rates of depression and suicide continue to be a concern, despite four decades of growing research into the mental health of farmers. Most farmers have an awareness of a need for improved mental health, but a lack of knowledge persists. As agricultural production demands increase and the number of family farms decreases, the stress placed upon farmers to support the food chain is higher than ever. Understanding the association between farm demands and resources among farmers is key for the development and implementation of programs to decrease occupational stress and depressive symptoms to improve mental health outcomes across farming …

Anxiolytic Intervention: Modulation Of Cell Types Due To Nicotine Withdrawal, Taylor Elder

Theses and Dissertations--Pharmacy

Nicotine use disorder (NUD) remains a leading cause of preventable disease, yet the neurobiological mechanisms underlying nicotine withdrawal are incompletely understood. Emerging evidence implicates neuroimmune signaling and astrocytic regulation of glutamate in shaping the withdrawal-associated affective phenotype. This dissertation investigated these processes using multiple nicotine administration paradigms including osmotic minipump implant, cigarette smoke exposure, and nicotine vapor inhalation to model diverse routes of human nicotine intake.

Chapter 2 examines the effects of these three modes of administration on neuroinflammation and validation of nicotine delivery. Nicotine exposure was confirmed through receptor [³H]Epibatidine nAChR binding assay and serum cotinine measurements. …

Investigating The Role Of Dynamic Signaling Of Nrg3-Erbb4 In The Prefrontal Cortex In Mediating Nicotine Withdrawal Phenotypes, Emily Prantzalos

Theses and Dissertations--Pharmacy

While several pharmacotherapies are currently available for nicotine use disorder (NUD), smoking cessation success rates remain below 10% each year. The molecular mechanisms underlying failed quit attempts continue to represent a critical gap in our knowledge. However, recent advances in understanding the genetic contributions to nicotine dependence offer a promising avenue for developing more effective cessation therapies. Prior research has identified genetic variation in Neuregulin 3 (Nrg3) and its cognate receptor ErbB4 as potential contributors to affective nicotine withdrawal (WD) phenotypes and cessation outcomes. Therefore, this dissertation aims to systematically investigate the region-specific, functional role of the Neuregulin Signaling Pathway …

Collision Avoidance Information System Utilizing Machine Learning Image Recognition, Michael W. Long

Theses and Dissertations--Mining Engineering

This thesis addresses significant safety challenges presented by powered haulage fatalities in underground mining by developing and evaluating a machine learning-driven Collision Avoidance Information System (CAIS). The research utilized a ZED 2i camera to capture both RGB and depth data for enhanced spatial awareness in visually limited underground environments. A specialized dataset of underground mining equipment was captured from limestone and zinc mines, annotated, and used to train a segmentation network. The CAIS was field-tested in diverse underground settings, achieving an accuracy of 82% in a limestone mine similar to the training data, but a lower accuracy of 45% in …

An Autonomous Robotic Inspection System For Underground Mines Using Unmanned Aerial Vehicles (Uavs), Kiazoa M. Joao

Theses and Dissertations--Mining Engineering

Underground mining environments pose unique safety challenges for workers due to poor visibility, unstable ground conditions, and the absence of GPS signals. To adhere to safety and health standards, underground mines are required to perform safety inspections regularly. Conventional safety inspections require personnel to enter the hazardous environment, highlighting the need for a safer, remote alternative. The use of UAVs for safety inspection in underground mines is a somewhat novel idea but has shown great promise. While Unmanned Aerial Vehicles (UAVs) cannot eliminate all hazards associated with mining, they provide critical support by accessing hazardous or restricted zones that are …

Analysis Of Dynamic And Final Surface Subsidence Movements Over Subcritical Panels In The Eastern Us, Mauricio Parra Valencia Sr

Theses and Dissertations--Mining Engineering

Subsidence prediction is a critical field in mining engineering, focusing on anticipating ground movements caused by underground coal extraction. Accurately forecasting these movements is essential for protecting surface structures and infrastructure from damage. However, despite extensive research by mining professionals worldwide, reliable prediction remains challenging, especially in complex environments like subcritical mining areas and locations characterized by highly variable topography. These conditions introduce non-linear rock mechanics that often complicate the application of traditional predictive models. This thesis utilizes measured subsidence data related to the extraction of two adjacent longwall panels in a deep coal mine in the eastern US to …

Simplified Molecular Diagnostics Methods For Environmental Testing Of Pathogens And Other Applications, Mohammad Dehghan Banadaki

Theses and Dissertations--Mechanical and Aerospace Engineering

Environmental Surveillance (ES) has emerged as a powerful tool to monitor the emergence and persistence of a pathogen within a facility or community using wastewater/water analysis. Over the past four years, implementation of ES has experienced an explosive acceleration, driven by efforts to monitor the spread of SARS-CoV-2, which has made ES a routinely used public health tool in many locations. We can now use ES to measure the emergence/presence/abundance of different viruses (e.g., SARS-CoV-2, influenza, mpox), bacteria (e.g., E. coli, V. cholerae, antibiotic-resistant strains), fungi (e.g., C. auris), and other biological markers indicative of infectious diseases. However, its broad …

Analysis Of Closed-Loop Dynamical Systems Using Relu Nns, Pouya Samanipour

Theses and Dissertations--Mechanical and Aerospace Engineering

This thesis develops a framework for analyzing the stability and invariance properties of closed-loop dynamical systems whose dynamics are derived from neural networks with rectified linear units (ReLUs). The ReLU neural network defines continuous piecewise affine (PWA) functions, which makes them ideal for analysis using polyhedral geometry and optimization techniques. To begin, we introduce two exact algorithms for enumerating polytopic regions of affine behavior induced by ReLU networks: a half-space-based method that checks the feasibility of activation patterns and a geometric vertex-based method. Using these methods, we are able to perform precise region-wise analysis, and these methods serve as the …

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 …

Simulation-To-Hardware Validation Of Mpc For Binary Thruster 2d Cubesat Control, Aevar Amundinusarson Oefjoerd

Theses and Dissertations--Mechanical and Aerospace Engineering

Small satellites must execute precise, fuel-limited maneuvers under strict actuation and operational constraints. Model Predictive Control (MPC) is a suitable approach because it optimizes future actions while explicitly enforcing these limits. This work evaluates (1) whether MPC can operate in real time using binary (on/off), asymmetric thrusters, and (2) whether a high-fidelity digital twin can be used to tune and validate the controller prior to hardware testing.

An MPC framework was implemented on a planar satellite prototype that floats on air bearings, operates at 16.7 Hz (60 ms period), and uses eight binary thrusters exhibiting up to 13.2% variation in …

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 …

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 …

Practicing Clinicians' Views Of The Life Participation Approach To Aphasia Therapy, Stephanie H. Mays

Theses and Dissertations--Communication Sciences and Disorders

The Life Participation Approach to Aphasia therapy (LPAA) aligns with a person-centered, functional approach to speech therapy. Past research has demonstrated that persons with aphasia (PWA) benefit from this approach and prefer it when compared to the traditional medical model to therapy. However, a disconnect between PWA preferences and SLP treatment approaches in therapy persists. This study aims to identify both barriers and facilitators that SLPs face when implementing LPAA. Five CCC-SLPs practicing in the state of KY with experience working with PWA were recruited as participants. Participants were placed into two focus groups, with each group meeting for 2-3 …

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 …

Biochemical And Biophysical Properties Of Failing Myocardium In Rare Patient Populations, Gregory Nathaniel Milburn

Theses and Dissertations--Physiology

Heart failure has diverse underlying etiologies, complicating research. While some types, like ischemic disease or inherited mutations, are well-studied, research on rarer forms has lagged. Understanding the molecular drivers in these populations may enhance diagnostics and therapies. This work examines two rare groups: patients with ATTR cardiac amyloidosis and those receiving mechanical assist device support. We show that myocardium from patients with amyloidosis has increased fibrosis and reduced force production without changes in cross-bridge kinetics. Additionally, we show that the passive stiffness of amyloidosis myocardium is not different from non-failing myocardium, indicating increased ventricular wall thickness may cause restrictive filling. …

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 …

Therapist Perspective Of Therapeutic Alliance And Treatment Outcome In Systemic Psychotherapy, Benjamin Larkin Mize Patterson

Theses and Dissertations--Family Sciences

One of the most robust findings in psychotherapy outcome research has been the relationship of a strong therapeutic alliance with improvement in treatment. Most research, however, has measured therapeutic alliance from the client’s point of view, disregarding the therapist’s perspective of this phenomenon. In this naturalistic study of adults in systemic individual, couple, or family psychotherapy (N = 627), both client- and therapist-ratings of alliance were assessed for their associations with treatment outcomes. Multilevel modeling was employed to analyze data from the Marriage and Family Therapy Practice Research Network (MFT-PRN). Client-ratings of the therapeutic alliance and general functioning/relationship satisfaction …

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 …