Digital Commons Network^™

Evaluation Of The Proclivity For Recovering Rare Earth Elements Via Heap Leaching Of Coal And Coal Byproducts, Dylan Connell

Theses and Dissertations--Mining Engineering

Rare earth elements (REEs) - 17 elements classified as light (LREE) or heavy (HREE) - underpin modern technology. This thesis presents the development, design, and testing of a heap leach pad (HLP) to extract REEs from Western KY No.13 seam coal refuse. Testing included resource estimation, column and heap leaching, and an economic feasibility study. Drillhole analyses identified average REE concentrations in two refuse piles of 286 ppm and 290 ppm. The resource base totaled approximately 7,085 metric tons of REOs. The HLP, constructed with 2,000 metric tons of coal refuse material, was tested continuously over 308 days. Fresh lixiviant …

Field-Assisted Post-Processing Of Cold-Sprayed Pure Copper, Alan Hensley

Theses and Dissertations--Mechanical and Aerospace Engineering

The properties of materials processed through cold spray, and many other AM processes, are non-uniform and unpredictable. In most cases, post-processing is required to achieve desired properties and better uniformity. In cold spray, the typical method is an annealing heat treatment (AHT), which can improve bond strength, reduce porosity, and restore ductility, among other effects. AHT alone, however, is unable to completely remedy any of the unfavorable properties. In addition, long treatments at high temperatures are often needed for satisfactory results. This increases energy consumption and extends production times for products made by the process. For these reasons, numerous investigations …

Multiphysics Transport In Porous Thermal Protection Systems: Experimental Characterization Of Gas Permeability And Radiative Properties, Yejajul Hakim

Theses and Dissertations--Mechanical and Aerospace Engineering

Porous thermal protection systems (TPS) used in hypersonic vehicles exhibit coupled gas and radiative transport across multiple regimes and length scales. Accurate performance prediction requires reliable characterization of permeability, slip-flow behavior, and radiative transport properties, particularly for low-permeability and charred materials where existing data are limited. This dissertation presents experimental methods for characterizing multiphysics transport in porous TPS materials. A modular flow system was developed to measure permeability and slip behavior in both virgin and charred materials under relevant environments. A transient pressure decay method enables accurate permeability estimation in low-permeability regimes and provides insight into effective pore structure. Results …

Reciprocity-Based Transfer Function Techniques For Acoustic Source Reconstruction, Spring Isolator Characterization And Structural Damping Assessment, David Pum Thian Lal Paite Neihguk

Theses and Dissertations--Mechanical and Aerospace Engineering

Reciprocity implies that a system responds identically when the source and receiver positions are interchanged. This dissertation applies this principle to address three practical challenges in noise and vibration characterization, where conventional approaches are limited by inaccessible interfaces, constrained excitation conditions, or metrics that do not fully capture vibroacoustic behavior.

The first study develops and validates an inverse method to characterize ducted acoustic sources using acoustic free velocity. Acoustic reciprocity is applied to simplify transfer function measurements. The method is extended to large cross-section ducts, where the source is reconstructed as a collection of point sources along a plane. Validation …

Process-Guided Learning Via Data-Driven Modeling And Controller Synthesis, Benton Clark

Theses and Dissertations--Mechanical and Aerospace Engineering

This work introduces process-guided learning, a framework in which process characteristics and learning algorithms are combined in the modeling process of engineering applications with the aim of uniting traditional and data-driven modeling and control techniques. Traditional engineering methods using simplified analytic models fail to capture the increasing complexities of engineering problems with sufficient accuracy to achieve modern requirements. More advanced modeling and control techniques using high-fidelity models often produce a computational burden that is infeasible for real-time solutions. Data-driven modeling offers a simple and flexible algorithm for producing real-time capable, high-fidelity models, but naive implementations lack the physical constraints of …

Human Resource Policy And Practice In The American Regional Theatre: The Intersection Of The Actors’ Equity Association And The League Of Resident Theatres, Kathleen Holland

Theses and Dissertations--Arts Administration

Human resource management plays a critical yet understudied role in the American regional theatre, an industry characterized by project-based labor, mixed union and nonunion workforces, and deeply ingrained cultural norms that prioritize artistic production over worker well-being. This dissertation examines how institutional human resource policies intersect with the Actors’ Equity Association (AEA) collective bargaining agreement and the League of Resident Theatres (LORT), and the implications of these intersections for human resource practice in regional theatre organizations. While entertainment-industry unions predate the formalization of contemporary human resource management, little scholarship has examined how union agreements may shape or substitute for organizational …

Improving Evaluation Practices Of Community Arts Extension Agents: A Mixed-Methods Study Leveraging Theory Of Change And Open Systems Theory, Melissa G. Bond

Theses and Dissertations--Arts Administration

This dissertation examines how a structured evaluation training and subject-based evaluation tool can strengthen evaluation practices among Community Arts Extension professionals in Kentucky. Community Arts programs often support outcomes such as belonging, connection, skill development, and cultural engagement, yet those outcomes can be difficult to document within standardized public reporting systems. Guided by Theory of Change and Open Systems Theory, this mixed-methods study combines an environmental scan of FY2020–FY2025 Community Arts indicator records and agent-authored Success Stories with three survey waves administered before training, immediately after training, and approximately 60 days later.

Findings show that routine reporting captured substantial activity …

Molecular Mechanisms And Metabolic Consequences Of Glucocorticoid Resistance, Genesee J. Martinez

Theses and Dissertations--Pharmacology and Nutritional Sciences

Glucocorticoids are vital steroid hormones that govern metabolism, stress responses, and immune functions through intricate, tissue-specific mechanisms, both genomic and non-genomic. These hormones bind to the glucocorticoid receptor (GR), which then acts as a transcription factor to modulate gene expression. Chronic elevation of glucocorticoid levels may lead to glucocorticoid resistance, resulting in adiposity, inflammation, and insulin resistance, thereby adversely affecting multiple metabolic tissues. Whether produced endogenously or administered exogenously, excessive, chronic glucocorticoid concentrations impair glucocorticoid signaling. Although there are two primary isoforms of the receptor, GR⍺ and GRβ, only GR⍺ interacts with glucocorticoids.Through the research conducted in this dissertation, we …

Expanding The Role Of Muscle Stem Cell Fusion In Muscle Under Hypertrophic Stimulus, Jensen Goh Zhong Sheng

Theses and Dissertations--Physiology

Muscle stem cells (MuSCs) are a unique stem cell population that can activate in response to both injury and growth stimuli. Studies on muscle regeneration have shown MuSC activation follows a uniform progression through proliferation, differentiation, and fusion. Therefore, to determine whether MuSC replication is a prerequisite for differentiation under hypertrophic stimulus, I used a lineage-tracking mouse model (Pax7^rtTA; TRE-H2B-GFP) to label MuSC nuclei and simultaneously tracked DNA synthesis via EdU incorporation. This dual-labeling approach allowed us to not only distinguish MuSC-derived nuclei but also demarcate which MuSC had proliferated prior to fusion. I then employed a mechanical …

Leveraging The Clinical Potential Of Spatially Fractionated Radiotherapy For Enhanced Therapeutic Impact & Rapid Management Of Large And Unresectable Tumors, Joshua Misa

Theses and Dissertations--Radiation Medicine

Annually, about two million people are diagnosed with cancer in the United States alone, with nearly half receiving radiation therapy during their course of treatment. Advances in radiation therapy focuses on widening the therapeutic window by maximizing the tumor local control while minimizing normal tissue toxicities. Since the 1950s, spatially fractionated radiotherapy (SFRT) has been a niche treatment technique for treating large, unresectable tumors while sparing the skin tissue. Unlike conventional radiation therapy, which delivers a uniform dose to the tumor, SFRT utilizes an alternating pattern of high- and low-dose irradiation regions. However, significant challenges and knowledge gaps remain, most …

Investigation Into The A/Ss Of Cervical Cancer And Its Effects On Tumor Control Probability In Radiation Therapy, Cameron Thayer-Freeman

Theses and Dissertations--Radiation Medicine

The standard of care for locally advanced cervical cancer is chemoradiation, consisting of conventional external beam therapy (EBT) followed by a boost of high dose rate (HDR) brachytherapy. These two radiation treatments will illicit different degrees of biological response depending on the tissue in question, and quantifying the overall effect the combined treatments will have require some form of biological modeling. The linear quadratic (LQ) model of cell survival is the most widely used radiobiological model in clinics across the nation.

It is quantified by the parameters a and ß, which model how radiation generates lethal damage in a population …

The Association Between Learned Helplessness And Future Outlook And The Mediating Effects Of Parental Support, Engagement, And Closeness, Allison N. Loosle

Theses and Dissertations--Family Sciences

The present study examined the direct and indirect associations between learned helplessness and future outlook among emerging adults, with parental support, engagement, and closeness as potential mediating factors. Using data from 375 participants drawn from G3, Wave 4 of the Youth Development Study, two path analytic models were tested: one including a composite measure of learned helplessness and one examining its components (contingency, cognition, and behavior) individually. Results indicated that higher levels of learned helplessness were associated with a less positive future outlook. When separated, the cognition and behavior components were negatively associated with future outlook, whereas contingency was not …

Optimizing Insect Exclusion Systems For Organic Specialty Crop Production, Elaine Losekamp

Theses and Dissertations--Entomology

Feeding damage from insect pests is a leading challenge for specialty crop growers who follow organic practices. Past research has shown that fine-mesh row covers installed over mesotunnel structures, which form a physical barrier between plants and insects, often reduce insect pest abundance and increase yield compared to open field conditions. However, there are several challenges associated with this practice. Exclusion efficacy varies across a spectrum of insect body sizes and mesh sizes, and effects on yield vary across crops. Additionally, pollination management for pollinator-dependent crops introduces labor requirements and may result in reduced pest exclusion efficacy. Mechanical weed management …

Breaking The Cycle: Financial Abuse And Mental Health Outcomes Among Women Survivors Of Intimate Partner Violence Through The Abc-X Model Of Family Stress, Angel Martinez-Johnson`

Theses and Dissertations--Family Sciences

The present study examined the relationship between financial abuse and mental health outcomes among women survivors of intimate partner violence (IPV) with particular attention to the roles of perceived financial knowledge and resilience. Guided by the ABC-X Model of Family Stress, this study explored whether these perceived resources function as mediators in the association between financial abuse and symptoms of anxiety, depression, and posttraumatic stress disorder (PTSD). Findings indicated that financial abuse was significantly associated with increased psychological distress across all three outcomes. Although perceived financial knowledge and resilience were significantly related to certain mental health outcomes, analyses did not …

The Impact Of Technology On The New Product Development Process For Intimate Apparel, Cassie M. Lambert

Theses and Dissertations--Retailing and Tourism Management

The purpose of this research was to provide a better understanding of how 3D CAD Software impacts the New Product Development Process of Intimate Apparel.  As a category, Intimate Apparel falls behind other categories in adopting new technology.  Interviews were conducted with industry professionals to explore their adoption and use of 3D CAD Software.  Two case studies were also conducted to compare the adoption strategies of a small and a large company.  Data coding of the interviews and case studies revealed similar relationships and common themes across all participants.  Findings show that the strategic implementation of 3D CAD Software reduces …

Equid Major Histocompatibility Complex (Mhc) Evolution & Genome Organization, Lauren C. Johnson

Theses and Dissertations--Veterinary Science

The evolution of modern horses has a well-documented fossil record and has long been of interest to the genetics community. Although non-caballine equids (e.g. zebras, donkeys, and asses) can hybridize with horses, the resulting offspring are typically infertile. Despite these reproductive barriers, genomic analyses reveal regions of high sequence similarity among equid species. This dissertation investigates the role of historical introgression in the evolution of modern Equus species. The first chapter re-evaluates earlier findings derived from a limited horse population and a single reference genome. The variants of the identified regions were pushed through Ensembl’s Variant Effect Predictor to assess …

Investigating The Full Annual Cycle Ecology Of Eastern Whip-Poor-Wills Breeding In Central Appalachian Forests, Nicole Notarianni

Theses and Dissertations--Forestry and Natural Resources

Data on habitat needs of migratory birds across the annual cycle is critical for the development of effective management plans, particularly for declining species. One declining species, the eastern whip-poor-will (Antrostomus vocerifus; EWPW) lacks data on habitat selection patterns through the annual cycle, and this knowledge is particularly scarce for the breeding season. In this thesis, I used archival GPS tags on EWPW to: 1) assess patterns of breeding habitat space-use for 11 EWPW breeding in central Pennsylvania, and 2) describe broad space-use patterns during migration and wintering seasons. Breeding data were paired with three LiDAR-derived habitat metrics: …

Using Camera-Based Unmarked Spatial Capture-Recapture Modeling To Estimate Reintroduced Elk (Cervus Canadensis) Population Parameters And Distribution In Southeastern Kentucky, Claire Marie Muia

Theses and Dissertations--Forestry and Natural Resources

Estimation of population parameters is important for wildlife management decisions. Elk reintroduced to southeastern Kentucky experienced early irruptive population growth and are currently monitored using a statewide harvest-based statistical population reconstruction model (SPR) across the Kentucky Elk Restoration Zone (KERZ). Because the SPR model is spatially coarse and difficult to scale to the smaller management units comprising the KERZ, we conducted a spatially explicit capture-recapture study using a clustered camera-trapping array deployed for 10 weeks from June–August 2024 to estimate elk population parameters within Management Unit 4. Due to a lack of resights of GPS-marked elk, population parameters were estimated …

Between The Rails: Experiential Education And Its Impact On Compliance And Consistency In Racetrack Surface Management, Heather Mackenzie

Theses and Dissertations--Community & Leadership Development

Recent regulatory requirements within the Thoroughbred racing industry have increased expectations for consistent collection and reporting of racetrack surface data. Despite clear standards, implementation in daily operations remains inconsistent, highlighting a gap between regulation, knowledge, and practice. This study examined the impact of an experiential education curriculum on racetrack personnel’s self-efficacy and reporting consistency.

Using a quantitative design, data were collected through pre- and post-surveys measuring self-efficacy and records of the number of days surface data were entered. Descriptive statistics, paired-samples t-tests, and effect size analyses were used. Results showed a statistically significant increase in self-efficacy (p < .001) with large effect sizes, indicating meaningful gains in confidence and comfortability. Reporting consistency did not show a statistically significant change (p = .885).

Overall, experiential education …

From Floodplain To Floodplain: Analyzing Stream And Riparian Restoration Methodologies And Impacts, Noah P. Lane

Theses and Dissertations--Biosystems and Agricultural Engineering

Stream restoration is a relatively new scientific field. Currently, there is not a definitive methodology for performing restorations that all professionals in industry and academia can agree upon. This has allowed for multiple ideologies to be developed and altered that vary by geographic location and the professional using them. In addition to the methodologies used, the publicly available design guidance published by state government organizations also varies by regulatory authority, method of analysis, ecoregion, and restoration objectives. In some cases, design guidance is replicated from a different geographical area and may not satisfy local needs or existing site conditions. Since …

Unseen To Unstoppable: Critically Redefining Care For Rural Women With Alcohol Use Disorders, Nicole Gerace

DSW Capstone Projects

Research reveals that rural women with alcohol use disorders (AUDs) are up to 90% less likely to seek treatment than men or urban women. This Doctor of Social Work capstone project brings together a systematic literature review (SLR), a conceptual paper, and a practice application paper to examine the clinical social work practice problem of rural women with AUDs underutilizing treatment. Collectively, these products investigate factors contributing to these disparities, identify gaps in care, and propose more equitable and responsive approaches to treatment for these women. This project began with an SLR (2020–2025) that investigated clinical treatment interventions that demonstrated …

Sepsis In Sight: Immersive Vr Simulation For Pediatric Training, Kelsey Wagler

DNP Projects

Abstract

Objectives: This project aimed to decrease the time required to administer antibiotics and fluid boluses to pediatric patients with sepsis by implementing a virtual reality (VR) simulation program. The initiative sought to enhance bedside nurses’ and pediatric residents’ knowledge, clinical reasoning, and confidence in sepsis assessment, early recognition, and evidence-based management. A secondary objective was to evaluate the effectiveness of VR simulation as an educational strategy for nurses in a high-acuity pediatric setting.

Design: This quality improvement project used a quasi-experimental design that incorporated a VR simulation intervention followed by a structured debriefing and targeted education session. Participants completed …

Stronger Together: Exploring The Impact Of Peer Support Meetings On Stress And Burnout In Ambulatory Nurse Managers, Sara Wellman

DNP Projects

Background

Nurse manager (NM) burnout is common and leads to decreased staff productivity, departmental effectiveness, and leadership capacity. This results in decreased staff morale, poor conflict management, and ineffective communication. Stress reduction and resilience programs have been shown to reduce burnout and enhance resilience in NMs, but more focus needs to be directed toward NMs who work in ambulatory settings.

Purpose

The aim of this project was to evaluate the effectiveness of a peer-to-peer resilience intervention in reducing stress and burnout among ambulatory nurse managers.

Methods

This project used a pre-test/post-test survey design and a convenience sample of ambulatory NMs. …

Rural Oral Health Access Coordination Program Proposal, Anna Luu

Theses and Dissertations--Public Health (M.P.H. & Dr.P.H.)

Oral health disparities remain a major public health issue in the United States, particularly in rural Kentucky, with barriers such as limited access to preventive dental services, transportation, and insurance coverage contributing to delayed treatment and worsening oral health outcomes. In response, the proposed Rural Oral Health Access Coordination Program aims to improve care access by strengthening referral systems, integrating oral health screenings into public health settings, and enhancing care coordination for high-risk populations. The program intends to focus on the Kentucky River District Health Department Region, connecting individuals to existing services rather than providing direct clinical care. Expected outcomes …

Adsorptive Gas Sensor Response Forecasting To Enable Breath-By-Breath Analysis, Samuel Bellaire, Samir Ahmed Rawashdeh, Kirby P. Mayer, Jamie L. Sturgill

Physical Therapy Faculty Publications

MOS gas sensors have proven to be useful in electronic noses, which utilize these sensors to detect volatile organic compounds in human breath to detect various lung diseases. Unfortunately, the long settling time of MOS gas sensors is ill-suited to measuring human breath, where complete breathing cycles are often shorter than 5 s. Existing studies circumvent this limitation by collecting gas samples and injecting them into a sealed chamber to react with the sensors. However, it would be convenient if breath-by-breath analysis could be conducted without the need to store breath samples. To accomplish this, we present a novel forecasting …

Exploring The Influence Of Quadriceps Peak Torque And Rate Of Torque Development On Running Mechanics After Anterior Cruciate Ligament Reconstruction, Amit M. Gohil, Gregory S. Hawk, Darren L. Johnson, Christopher S. Fry, Brian W. Noehren

Physical Therapy Faculty Publications

Background: After anterior cruciate ligament reconstruction (ACLR), chronic changes in knee joint biomechanics during higher level tasks, such as running, may negatively impact long-term knee joint health. Among the factors that contribute to these chronic changes, the influence of quadriceps strength on knee joint biomechanics during running is not well understood.   Hypothesis: Higher involved limb quadriceps strength (peak torque and rate of torque development [RTD]) and limb symmetry index (LSI) will be positively associated with greater peak knee flexion angle and peak knee extensor moment during running.   Study Design: Cross-sectional study.   Level of Evidence: Level 3.   Methods: Peak knee extensor …

Catwalk Xt Enables Sensitive Detection Of Locomotor Deficits After C2 Hemisection And Integrates Readily Into Ongoing Experimental Workflows In Adult Female Rats, Aaron L. Silverstein, Christopher M. Calulot, Christopher J. Mclouth, John C. Gensel, Warren J. Alilain

Biostatistics Faculty Publications

Over half of all spinal cord injuries (SCIs) in the United States occur at the cervical level and often cause both life-threatening breathing dysfunction and profound locomotor deficits. Although the C2 hemisection (C2Hx) model is vital for study of breathing dysfunction after experimental SCI, post-C2Hx locomotor deficits have only been assessed by metrics such as the Martínez Scale and ladder tests, which require time-intensive scoring by human observers. However, the CatWalk XT Gait Analysis system (Noldus Information Technology) delivers automated, quantitative assessment of interlimb coordination, gait cycle, and paw function, providing robust locomotor data in a time-efficient and practical manner. …

Integration Of Community-Engaged Research Technology And Methods To Guide Tobacco Regulatory Science In Rural Communities, Melissa H. Abadi, Stephen R. Shamblen, Mary Kay Rayens, Kirsten T. Thompson, Amy Wildman, Kathy Rademacher, William Wieczorek, Raphael Nishimura, Shyanika W. Rose, Mikhail N. Koffarnus, Seth Himelhoch, Ellen J. Hahn

Biostatistics Faculty Publications

Objective – This study aims to build a rural Appalachian cohort to examine how US Food and Drug Administration (FDA) Center for Tobacco Products (CTP) regulatory policies influence tobacco and nicotine product use across levels of rurality. Methods – The AppalTRUST (Appalachian Tobacco Regulatory Science Team) Cohort integrates four inter-connected Community-engaged Research + Technology (CEnRT) elements to support recruitment and retention: (1) building trust and cultural relevance; (2) addressing barriers to participation in research; (3) focusing on ethics and confidentiality; and (4) fostering ongoing and consistent collaboration between the scientific and field teams. The study uses a dual sampling design …

Rethinking Team Science Metrics Through Collaborative Guideposts, Kristen J. Mcquerry, Kelsey Karnik, Megan E. Hall, Caitline Phan, Yana Feygin, Emily Slade

Biostatistics Faculty Publications

Introduction – The increasing reliance on interdisciplinary and transdisciplinary teams has reshaped how science is conducted, yet evaluating the success of such teams remains a persistent challenge. Traditional metrics, such as publication counts, impact factors, and citation indices, fail to capture the full scope of team contributions, particularly in contexts where success may be defined by community engagement, mentorship, or long-term collaboration. Methods – In this Perspective, we introduce Collaborative Guideposts, a framework designed to align success metrics with a team’s organizing priorities. We illustrate this approach through two contrasting team models from a biostatistical collaboration center: Team A, a …

The Influence Of Support From Family, Friends, And Community On Perceived Mental Health Status In Diabetes, Courtney L. Ortz, Meredith S. Duncan, Oluwatosin Leshi, Suraksha Khanal, Brittany Smalls

Biostatistics Faculty Publications

Strong social support is a protective factor in diabetes and mental health management. The purpose of this study was to examine the influence of the type of support on perceived mental health status among people with diabetes. We used data from the 2021 Household Component of the Medical Expenditure Survey (MEPS). Regression models assessed the association between mental well-being (outcome) and expected help from family, friends, and the community (exposure). Support from both friends and family were significantly associated with better mental well-being, adjusting for covariates. Secondary analyses showed that those who reported greater anticipated support from family were more …