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Scaling Investigations Of Wall-Bounded Turbulent Flow, Nikolay Gustenyov

Theses and Dissertations--Mechanical and Aerospace Engineering

This dissertation investigates the scaling behavior, structural organization, and modeling of turbulence in wall-bounded flows across a wide range of Reynolds numbers and surface conditions. Through high-resolution experimental studies in zero-pressure- gradient turbulent boundary layers and pipe flows (2000 < Reτ < 38 200), the wall- dependence of turbulent length scales is examined with a focus on both small-scale dissipative motions and large-scale structures. When external intermittency is properly accounted for, dissipative motions are shown to obey inner scaling even in outer- scaled regions, while large-scale motions exhibit outer scaling behavior deep into the inner region. These findings are consistent across internal (pipe) and external (boundary layer) flows and are reflected in distinct features of the longitudinal wavenumber spectrum.

The dissertation also explores the development of a turbulent boundary layer transitioning from a smooth solid wall to a liquid surface. An internal boundary layer forms in response to stochastic surface waves, resulting in increased turbulence intensity and displaced momentum relative to solid-wall cases. Near the liquid surface, turbulence generation aligns with wavenumbers corresponding to the surface waves, introducing distinct small-scale …

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 …

Fluid Pathways For Enhanced Mass Transfer In The Micro Regime: Applications In Novel Pumpless Redox Flow Cell And Zinc Finger Protein-Based Dna Detection, Shaikh Al Mahmud Bhuiyan

Theses and Dissertations--Mechanical and Aerospace Engineering

Precise fluid transport through microscale geometries can help optimize electrochemical and biochemical processes by maximizing the mass transfer rate of reactants. By introducing intricate structural features inside microchannels, it is possible to manipulate the fluid motion and direct the flow towards any surface of interest. In this study, we have demonstrated that rationally designed fluid pathways can improve the performance of electrochemical and biochemical systems.

The emergence of additive manufacturing has enabled rapid fabrication of robust structures with intricate features to guide fluid motion. However, their application in nonaqueous electrochemical systems has been limited due to their interaction with organic …

Direct Numerical Simulation Of Pulsating Flow In Curved Pipes: Insights Into Aortic Dissection In Humans, Gokul Anugrah Gopakumar

Theses and Dissertations--Mechanical and Aerospace Engineering

This dissertation investigates the hemodynamics of pulsating blood flow in curved vessels through direct numerical simulations (DNS), with the overarching aim of uncovering fluid dynamic mechanisms linked to the onset and progression of aortic dissection in humans. The work is structured in two parts: (i) fundamental studies in idealized geometries and (ii) preliminary investigations in patient-specific anatomies. In the first part, curved pipe models representing the aortic arch are used to isolate the effects of pulsation frequency, amplitude ratio, and curvature ratio on transitional and turbulent flow dynamics. The simulations reveal that curvature-driven centrifugal forces shift the peak velocity toward …

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 …

Impact Of Hyperthermia And Mitomycin C On Heat Shock Proteins, Mismatch Repair Proteins, And Cytotoxicity In Colon Cancer, Anna M. Reagan

Theses and Dissertations--Clinical and Translational Science

Cytoreductive surgery and heated intraperitoneal chemotherapy (HIPEC) is a treatment used for primary peritoneal malignancy or metastases, including colon cancer. We aimed to explore the effects of hyperthermia and/or mitomycin C (MMC) on mismatch repair (MMR) proteins and heat shock proteins (hsps) and the potential for post-HIPEC treatment with pembrolizumab treatment. Colon cancer cells were treated with hyperthermia and/or MMC for 90 minutes. Subcellular fractionation and immunofluorescent imaging were performed to identify protein abundance and localization of MSH2, MLH1, hsp70, and hsp27. Proteomics analysis was performed for HT29 cells. HT29 cells and patient-derived organoids (PDOs) underwent simulated HIPEC and treatment …

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. …

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 …

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 …

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 …

Causes And Consequences Of Reproductive Plasticity In The Seed Beetle, Callosobruchus Maculatus, Josiah P. Ritchey

Theses and Dissertations--Entomology

Competition for resources has direct effects on traits that can influence an individual’s reproductive success in competitive mating environments. When population density is high during development, competition for resources can reduce growth and body size at maturation, influencing resources available for reproduction. In this thesis, I investigate how the developmental environment affects plasticity in male reproductive traits, as well as the consequences of male reproductive plasticity on female reproductive behavior, in the seed beetle, Callosobruchus maculatus. My results show that increasing larval density causes male beetles to emerge small and transfer small ejaculates to females. However, small males transfer …

Dinotefuran Resistance In The German Cockroach (Blattella Germanica L.), Hannah F. Blevins

Theses and Dissertations--Entomology

German cockroaches (Blattella germanica L.) are one of the most prevalent and pervasive indoor pest species in the world. Infestations can lead to many negative impacts on humans, including sensitization to allergens, increase in asthmatic symptoms, mental health declines, and potentially, the spread of diseases. While insecticides remain the most effective and affordable option for German cockroach control, resistance to many commonly used insecticide active ingredients (AIs), such as pyrethroids, has been observed globally at high levels across different populations. Given such resistance to pyrethroids, inclusion of insecticides with alternative modes of action into insecticidal treatments could potentially improve cockroach …

Engineering Novel Biomimetic Models Of Equine Host-Microbe Interactions, Lynn M. Leedhanachoke

Theses and Dissertations--Veterinary Science

One major limitation to the study of equine disease is the lack of in vitro models that accurately reflect the dynamic physiology of the horse. Thus, there is a pressing need to develop in vitro systems that recapitulate diverse equine tissue and organ microenvironments. To overcome this deficiency, we developed multiple biomimetic equine organoid systems that can be employed for a variety of investigations aimed at resolving outstanding questions in infectious disease pathogenesis, therapeutic development and drug metabolism, host defense mechanisms, immune-modulated disease, and equine developmental biology. Our innovative platform incorporates novel equine intestinal enteroid and airway organoid models derived …

Development Of Non-Destructive Methods For The Detection And Quantification Of Gluten Sources In Foods, Adewale Abiola Oloyede

Theses and Dissertations--Biosystems and Agricultural Engineering

Cross-contamination of food with gluten-rich grains such as wheat, barley, and rye remains a significant challenge in gluten-free food production, posing health risks to individuals with gluten-related disorders. Traditional detection methods are often time-consuming and labor-intensive, highlighting the need for rapid and reliable alternatives. This study investigates the use of hyperspectral imaging (HSI) combined with machine learning (ML) and deep learning (DL) techniques for the detection and quantification of gluten contamination in grain-based foods through three main approaches: (i) classification of gluten source contaminants in gluten-free flour, (ii) quantification of gluten content from wheat, rye, and barley flours, and …

“What We Say Matters”: Reducing Drug Use Stigmatization By Healthcare Professionals Through A Narrative-Based Awareness Campaign, Adam M. Traugott

DNP Projects

Background: Stigma towards substance use has been identified as a contributor to poor care and health outcomes amongst people who use drugs (PWUD), a vulnerable population. Healthcare worker stigma negatively affects the outcomes of individual patients and may have greater public health implications. Methods of addressing drug-use stigma have previously been implemented in a variety of clinical settings. Presenting the lived experience of PWUD to healthcare workers via emotionally compelling narratives has been found to be an effective means of stigma reduction.

Purpose: This study utilized two psychometrically validated tools to measure (1) the baseline prevalence of drug use stigma …

Effects Of An Active Ankle Exoskeleton On The Walking Biomechanics Of Healthy Men, Sridevi Nagaraja, Jose E. Rubio, Junfei Tong, Aravind Sundaramurthy, Anup Pant, Meredith K. Owen, Michael A. Samaan, Brian W. Noehren, Jaques Reifman

Physical Therapy Faculty Publications

Active lower-body exoskeleton devices can decrease the energy requirement of the human body by providing mechanical assistance to lower-body muscles. However, they also alter gait kinematics and kinetics, and it is not well understood whether such alterations are detrimental or beneficial to the human body. In this pilot study, we investigated the impact of walking with an ankle exoskeleton device on the biomechanics of men while carrying a heavy load. We collected computed tomography images and motion-capture data for five young, healthy men who walked 5 km (∼60 min) with a 22.7-kg load, with and without an active ankle exoskeleton …

A Myostatin Inhibitory Antibody Combined With Insulin, Partially Rescues The Musculoskeletal Phenotype Of Female Insulin-Deficient Diabetic Mice, R. Clay Bunn, Reuben Adatorwovor, Philip D. Ray, Alexander R. Keeble, Christopher S. Fry, Sasidhar Uppuganti, Jeffry S. Nyman, John L. Fowlkes, Evangelia Kalaitzoglou

Biostatistics Faculty Publications

Introduction: Type 1 diabetes is associated with deficits in both skeletal muscle and bone. Inhibition of myostatin, a negative regulator of muscle mass, was explored as a druggable target to improve the musculoskeletal phenotype associated with insulin-deficient diabetes in female mice. Methods: We investigated whether administration of an inhibitory myostatin antibody (MyoAb) in streptozotocin-induced diabetes in female mice is protective for skeletal muscle and bone. DBA/2J female mice were injected with low-dose streptozotocin or with citrate buffer (vehicle). Subsequently, mice were implanted with insulin-containing or vehicle pellets, with groups being randomized to myostatin or control antibody for 8 weeks. At …

Clonal Hematopoiesis Of Indeterminate Potential And The Risk Of Cognitive Impairment In The Women’S Health Initiative Memory Study, Yasminka A. Jakubek, Aaron P. Smith, Xiaoyan I. Leng, Megan E. Hall, Daniel Ezzat, Yash Pershad, Jason M. Collins, Md Mesbah Uddin, David W. Fardo, Pradeep Natarajan, Alexander G. Bick, Jacob O. Kitzman, Michael C. Honigberg, Kathleen M. Hayden, Joann E. Manson, Siddhartha Jaiswal, Eric A. Whitsel, Alexander P. Reiner

Internal Medicine Faculty Publications

INTRODUCTION

Clonal hematopoiesis of indeterminate potential (CHIP) confers an increased risk of several chronic aging-related diseases. Paradoxically, CHIP was associated with lower risk of dementia in recent studies.

METHODS

We examined associations between baseline CHIP and incident mild cognitive impairment (MCI) and/or probable dementia in the Women's Health Initiative Memory Study. CHIP was detected using blood-based targeted sequencing. Cox proportional hazards models examined time to onset of cognitive impairment, adjusting for traditional risk factors.

RESULTS

Using a conventional variant allele fraction (VAF) threshold of 2%, CHIP was not associated with incident cognitive impairment. The presence of larger CHIP clone (VAF …

Characterization Of Municipal Solid Waste Using Machine Learning Based Imaging And Chemical Analysis, Enyonam Ahadzi

Theses and Dissertations--Biosystems and Agricultural Engineering

According to the U.S. Department of Energy’s 2023-billion-ton report, the United States generates nearly 300 million tons of municipal solid waste every year. More than 50% of that waste is underutilized and ends up in landfills. This poses serious public health and environmental risks. But beyond the environmental and health implications, this is also a wasted opportunity. The U.S. Energy Information Administration estimates that, for every 100 lbs of waste we throw away, about 85% can be used as fuel or for electricity generation. However, its complex and heterogeneous nature poses challenges for efficient sorting and valorization in waste to …

Information-Theoretic Methods For Efficient Training And Robust Evaluations In Self-Supervised Learning, Oscar Skean

Theses and Dissertations--Computer Science

Self-supervised learning (SSL) has become a cornerstone of modern machine learning, offering a scalable alternative to costly human annotation by constructing pretext tasks directly from raw data. While SSL has delivered strong results across vision, language, and multimodal domains, two major limitations persist: (1) SSL methods are often significantly slower to train than supervised counterparts, and (2) evaluation protocols remain narrow, with most studies relying on linear probing accuracy on the pretraining dataset. . These challenges are particularly acute for large language models (LLMs), where training costs and interpretability of intermediate representations are critical concerns.

In this work, we propose …

Assessment Of Cerebrospinal Fluid And Blood-Based Biomarkers In Degenerative Cervical Myelopathy: Systematic Review And Meta-Analysis, Harshit Arora, Hassan Darabi, Cassandra C. Wolsh, Kelsey N. Karnik, John C. Gensel, Francis Farhadi

Neurosurgery Faculty Publications

Study Design: Systematic Review and Meta-Analysis.

Objectives: Degenerative cervical myelopathy (DCM), the leading cause of spinal cord injury globally, may clinically manifest with hand numbness and tingling, loss of hand dexterity and impaired balance and gait. Biomarkers have been identified as disease indicators with recent studies exploring the role of structural and inflammatory biomarkers in diagnostic and treatment outcome prediction. The review aims to identify relevant cerebrospinal fluid (CSF) and blood-based biomarkers associated with DCM diagnosis and prognostication.

Methods: The systematic review was conducted as per PRISMA guidelines. A comprehensive search strategy was devised to identify articles evaluating biomarkers in …

A High-Resolution Record Of Late Holocene Drought In The Eastern Sierra Nevada (California, Usa) From June Lake Carbonate Geochemistry, Eva C. Lyon, Andrea M. Erhardt, Laura C. Streib, Susan R.H. Zimmerman, Michael M. Mcglue

Earth and Environmental Sciences Faculty Publications

As historic drought conditions become more common in western North America, Late Quaternary hydroclimate records become vital for putting present anthropogenic conditions into a longer-term context. Here, we establish a high-resolution record of drought for the eastern Sierra Nevada (California) using lacustrine carbonates from well-dated sediment cores. We used oxygen and carbon stable-isotope ratios, combined with high-resolution scanning X-ray fluorescence counts of calcium (Ca) and titanium (Ti), to reconstruct the drought record over the last 4600 years in June Lake. We found elevated δ¹⁸O and δ¹³C carbonate isotope values coinciding with peaks in both total inorganic …

Addressing Municipal Road Aid Funding In Kentucky During The Era Of Electric Vehicles, Jacob Bruce, Tyler Chapman, Blake Girdler

MPA/MPP/MPFM Capstone Projects

The rapid rise of electric vehicles (EVs) poses a growing threat to Kentucky’s Municipal Road Aid Fund, which relies heavily on fuel tax revenues. As EV adoption increases and fuel consumption declines, the existing funding model becomes increasingly unsustainable, jeopardizing road maintenance, infrastructure development, and municipal services across the state. Commissioned by the Kentucky League of Cities, this study investigates viable policy solutions to ensure long-term fiscal stability for municipal road funding in an electrifying transportation landscape. Drawing from comparative analyses of peer and neighboring states, the report evaluates alternative funding mechanisms such as road usage charges, EV-specific registration fees, …

Sex-Specific Roles Of The Adipocyte Mineralocorticoid Receptor In Obesity And Early Life Stress, Meghan B. Turner

Theses and Dissertations--Pharmacology and Nutritional Sciences

Obesity is a burgeoning health epidemic caused by chronic overnutrition and exacerbated by genetic, environmental and developmental factors. The adipocyte mineralocorticoid receptor (MR), a transcriptionally active nuclear receptor, is speculated to contribute to metabolic dysfunction in the obese state. MR expression is increased in obese adipose tissue, and MR modulates the expression of fat-derived hormones such as leptin and adiponectin. In women, obesity can be exacerbated by early life stress, such as adverse childhood experiences (ACEs). Studies show that women display a positive association between cumulative ACE exposures and increased body mass index. Previously, we demonstrated that maternal separation and …

Exploring The Collective Efficacy Of Elementary Special Education Teachers And Its Relationship To Distributed Leadership, Emma L. Jones

Theses and Dissertations--Educational Leadership Studies

This study examined the relationship between collective teacher efficacy (CTE) and distributed leadership practices among elementary special education teachers. CTE reflects teachers’ shared belief in their collective ability to improve student outcomes, while distributed leadership emphasizes shared decision-making, collaboration, and shared responsibility across school personnel.

Using a sequential explanatory mixed-methods design, the study combined survey data from the Collective Teacher Belief Scale with follow-up interviews. Survey results from 31 special education teachers indicated moderate to high levels of CTE, with slightly greater confidence in managing student behavior than in delivering instruction. Interviews with teachers across varying CTE levels provided deeper …

Using The Mand-Model Intervention Strategy To Increase Verbal Or Augmentative And Alternative (Aac) Two-Word Utterances For Requesting Items In A Naturalistic Setting, Morgan A. Williams

Theses and Dissertations--Education Sciences

This project examined the effectiveness of the mand-model milieu teaching strategy for increasing two-word verbal or augmentative and alternative communication (AAC) requests in a classroom. Three students participated. All students demonstrated increased mean length of utterance in words (MLUw) when requesting preferred items. For all students, correct two-word requests improved following a model prompt. Two students showed limited independent requesting following only a mand, while one student met criterion for consistent independent requesting. Other observed outcomes included improved communicative confidence, reduced frustration behaviors, and increased AAC acceptance and generalization across settings for one participant. Findings suggest that the mand-model strategy …

Effect Of Walking With An Active Ankle Exoskeleton On The Biomechanical Responses Of The Lumbar Spine, Jose E. Rubio, Junfei Tong, Aravind Sundaramurthy, Anup Pant, Sridevi Nagaraja, Meredith K. Owen, Michael A. Samaan, Brian W. Noehren, Jaques Reifman

Physical Therapy Faculty Publications

Objective: Musculoskeletal injuries pose a health threat to U.S. Service members. In particular, the physical demands of walking and running with load carriage contribute to a high incidence of musculoskeletal injuries of the lower back. Active ankle exoskeleton devices are promising technologies that may help mitigate the impact of load carriage on the incidence of these injuries. However, the safe extended use of these devices requires an understanding of their beneficial or detrimental effects on the lumbar spine. In this pilot study, we investigated the impact of walking with an ankle exoskeleton device on lumbar biomechanical responses.

Methods: We collected …

Comparison Of Machine Learning Models For Colon Cancer Survival: Predictive Modeling Approach, Reuben Adatorwovor, Motolani E. Ogunsanya, Bin Huang, Richard Charnigo, Olufunmilola Abraham

Biostatistics Faculty Publications

Background: Colon cancer is a leading cause of cancer-related deaths worldwide, with survival influenced by risk factors, treatment type, and patient characteristics. Traditional statistical models, such as Kaplan-Meier curves, have been widely used to estimate survival probabilities. However, these models often have difficulty handling complex interactions, covariates, and nonlinear relationships between risk factors. Recently, machine learning (ML) techniques have emerged as promising tools for improving survival prediction by handling large covariates and capturing complex patterns.

Objective: This study compares several ML models to accurately estimate colon cancer survival by leveraging data from the Kentucky Cancer Registry. By identifying key risk …

Minority In Baroque Trumpet Repertoire: Minor-Key Literature For Baroque Trumpet, Wing Heng Victor Yuen

Theses and Dissertations--Music

The repertoire for trumpet in the Baroque era is overwhelmingly in major keys for obvious reasons. As natural trumpet is limited by design to play the notes of the harmonic series, most players have little access to sonorities outside the major scale and arpeggios within the series without the help of technical innovations such as the slide, and much later, vent-holes. Baroque trumpet makers built valveless natural trumpets, which are limited by design to play the notes of the harmonic series. Since the fundamental physics limit the musical notes available to the natural trumpet, minor key is not an essentially …