Digital Commons Network^™

Injectable Formulations For Localized Delivery Of Immunomodulators, Ketki Velankar

Electronic Theses and Dissertations

Dysregulation of immune homeostasis is fundamental to the development of autoimmune disorders. Fibroblastic reticular cells (FRCs) within lymph nodes play crucial roles in forming a microenvironment conducive to immune cell interactions and regulating autoreactive T cells driving autoimmune diseases. Studies have shown the potential of FRCs as a form of personalized cell therapy to correct dysregulated immune responses. Successful translational efforts, however, require the cells to be formulated as injectable suspensions while retaining their native architecture, which is essential for their regulatory functions. The main challenge resides in retaining the native reticular organization of FRCs lost in conventional monolayer cultures …

Steroid Sulfatase In Rodent Tissues And A Cell Line: Characterization, Regulation And Inhibition, Barathi Balasubramonian

Electronic Theses and Dissertations

Inactive sulfated steroids are present in plasma at higher concentrations than unsulfated ones. Steroid sulfatase (STS) is the enzyme that removes the sulfate group from sulfated steroid hormones in local tissues, making them active. High levels of STS are linked to breast and prostate cancers, and low levels of STS cause behavioral disorders and X-linked ichthyosis. STS is present in most tissues, yet its physiological role is uncertain. We sought to characterize STS activity in several rodent model systems in order to learn more about its function. Three different sets of experiments were conducted. First, we examined STS in mouse …

Uptake Of Extracellular Vesicles Into Brain Endothelial Cells And Development Of Motor Neuron-Derived Extracellular Vesicles For Amyotrophic Lateral Sclerosis, Jhanvi Rajan Jhaveri

Electronic Theses and Dissertations

Extracellular vehicles (EVs) are an emerging class of drug carriers and are primarily reported to be internalized into recipient cells via a combination of endocytic routes such as clathrin-mediated, caveolae-mediated and macropinocytosis pathways. In part one of this thesis, (1) we investigated potential effects of homotypic vs. heterotypic interactions by studying the cellular uptake of homologous EVs (EV donor cells and recipient cells of the same type) vs. heterologous EVs (EV donor cells and recipient cells of different types) and (2) determined the route of EV internalization into low pinocytic/hard-to-deliver cell models such as brain endothelial cells ( …

Delivery Of Mitochondria-Containing Engineered Extracellular Vesicles To The Blood-Brain Barrier For Ischemic Stroke Therapy, Kandarp Dave

Electronic Theses and Dissertations

Ischemic stroke is the second leading cause of death worldwide, and the lack of effective treatment options is an unmet clinical need for stroke survivors. Ischemic stroke-induced oxygen-glucose deprivation (OGD) in the affected brain tissue leads to mitochondrial dysfunction and adenosine triphosphate (ATP) depletion in the brain endothelial cells (BECs) lining the blood-brain barrier (BBB). ATP deprivation in the BECs dysregulates actin cytoskeleton dynamics, resulting in BBB breakdown. Restoration of blood flow (i.e., reperfusion) upon the first-line stroke treatment further leads to BBB breakdown and widens the paracellular spaces between BECs. …

Macromolecular Crowding Effects On Enzymes That Display Non-Hyperbolic Kinetics, Kelsey A. Aldrich

Electronic Theses and Dissertations

Macromolecules occupy up to 30% of a cell's volume, yet the in vitro study of biological processes is almost exclusively performed in dilute solutions that fail to approximate the crowded interior of a cell. A growing body of literature has identified that macromolecular crowding has significant effects on a number of biochemical processes, including enzymatic activity. However, changes in kinetic parameters with increased macromolecule concentrations have only been determined for enzymes that follow hyperbolic Michaelis-Menten kinetics, despite the fact that over 25% of enzymes deviate from this model. Here, we perform the first characterization of macromolecular crowding effects on …

Open-Source Forensics Tools Are Great Tools For Critical Used Machines, Erik Herrera

Electronic Theses and Dissertations

Open-Source software exists on everything from operating systems to daily productivity applications. In digital forensics, a very popular tool that is used to learn on and expand is Autopsy. Autopsy is known in the digital world due to its potential and wide usage. It is in many built packages of software inside the open-source world of applications. It is built into premade operating systems that are involved in Digital Forensics and Penetration Testing. Prebuilt OS includes Kali Linux and Computer Aided Investigative Environment (CAINE).

In the application to defend Open-Source software being just as good as closed-source software, I will …

Chinese Tallow Long-Term Impact On Stand Dynamics In A Bottomland Hardwood Forest Following Vegetation Management, Nicklaus R. Langlois

Electronic Theses and Dissertations

Chinese tallow (Triadica sebifera (L.) Small) is an invasive tree known to have negative impacts on bottomland hardwood forests. Chinese tallow is proficient in reproducing and surviving in bottomland hardwood forests because it is more flood and shade tolerant than most native trees. The long-term effectiveness of Chinese tallow control is an important topic to research as only a few long-term studies of Chinese tallow control have been conducted. A 10-year re-measurement of 22 paired plots installed in 2012 on the Pineywoods Mitigation Bank near Diboll, Texas following herbicide treatments examined Chinese tallow and native tree stand structure. Each …

Rna Secondary Structures: Structure-Function Studies In Viral And Neurodegenerative Diseases, Caylee Cunningham

Electronic Theses and Dissertations

The studies within this dissertation highlight the importance of RNA structure and function, highlighting potential mechanisms in the pathogenesis of the SARS-CoV-2 virus and hallmarks of ALS. Specifically, the s2m, a 41-nt structure found within the hyper variable region of the 3’ UTR of the SARS-CoV-2 virus, was investigated as this element has no definitive role in viruses but its high conservation in several viral families warrants investigation. We used various biophysical techniques to determine if a palindromic sequence in the terminal loop could participate in dimerization activities, which may have implications in recombination and the longevity of the virus. …

The Impact Of Internal Curing Additives On Compressive Strength, Shrinkage, And Internal Relative Humidity Of Mortars., Payton Scott

Electronic Theses and Dissertations

Curing is a critical step in concrete construction. When a concrete specimen is properly cured, its shrinkage and early age curling/warping can be reduced, and the concrete strength can be increased. Curing methods can be divided into two categories: traditional external curing and emerging internal curing methods. Internal curing has similar benefits to external curing, such as reduced early-age cracking and shrinkage risk, and increased durability and strength. The purpose of this research is to investigate internal curing additives and their impact on length change, weight change, compressive strength, autogenous shrinkage, and internal relative humidity. Mortar mixtures with lightweight aggregate …

Carboxen Micropreconcentrator Performance For Analyzing Btex In Air., Raymond Daniel Spargo

Electronic Theses and Dissertations

Volatile Organic Compounds (VOCs) are a class of toxic chemicals in environmental air associated with several serious health risks. Some of the most common and concerning VOCs are Benzene, Toluene, Ethyl Benzene, and Xylene (BTEX). To maintain healthy air quality in these environments, researchers pursue instruments and processes to quickly and accurately predict sub-ppb concentrations of BTEX in indoor and outdoor air. By employing a micropreconcentrator (μPC) to combine Solid-Phase Micro-Extraction (SPME) with Gas Chromatography Mass Spectrometry (GC-MS) analysis, trace BTEX content in air samples can be captured, extracted and analyzed. In this thesis, a dual-compartment μPC with Carboxen 1000 …

Venturing In Limbo: Entrepreneurial Resourcefulness By The Forcibly Displaced., Sadek Showkat

Electronic Theses and Dissertations

Entrepreneurial resourcefulness is an overarching concept in the entrepreneurial process that has gained momentum among theorists and practitioners. Traditionally, entrepreneurial resourcefulness is theorized as a state—a behavior or trait—rather than a process. However, our understanding of this concept changes significantly when viewed through the lens of the lived experiences of forcibly displaced individuals. This dissertation presents a theoretical and empirical investigation of how these entrepreneurs pursue entrepreneurial resourcefulness through three interrelated essays. The first essay provides a problematizing review and introduces a novel typology (exogenous vs. endogenous) that captures the heterogeneity of the construction of entrepreneurial resourcefulness across …

Epidural Stimulation For Urogenital Dysfunction In The Spinal Cord Injured Rat., Natasha Lorraine Wilkins

Electronic Theses and Dissertations

Spinal cord injury (SCI) is a devastating, life changing event that greatly impacts quality of life. SCI can have body-wide, multi-system consequences including dysfunction within the urogenital system. Challenges with the urinary system include urinary incontinence, urine retention, and detrusor-sphincter dyssynergia all of which require maintenance through the regular use of catheters. Sexual dysfunction in men, who comprise nearly 80% of the SCI population, includes erectile dysfunction, anejaculation, retrograde ejaculation, poor expulsive force during ejaculation, and poor sperm quality. The treatment for sexual function in SCI men is focused more on fertility through the collection of sperm for insemination procedures …

Natural Fiber Reinforced Composites For Sustainable Additive Manufacturing., Athira Nair Surendran

Electronic Theses and Dissertations

Carbon fiber is widely known for its exceptional strength, making it a sought-after material in composite manufacturing, especially with thermosets and thermoplastics. Its major applications span aerospace, wind turbines, sports equipment, automotive interior and exterior parts, robotics and medical equipment. Recently, carbon fiber filament manufacturing has gained attention due to the availability of desktop 3D printers and the versatility and customizability that comes with the realm of 3D printing. Commercial carbon fiber production, primarily from polyacrylonitrile (PAN), is energy-intensive and derived from crude oil, contributing to significant environmental impacts and poor recyclability. Alternatively, lignocellulosic natural fibers present a possible sustainable …

Synergistic Strategies In Hybrid Mxed Matrix 3d Printing Of Thermoplastics & Thermosets: Design, Manufacturing, And Materials Development., Saleh Akram Khanjar

Electronic Theses and Dissertations

Composite manufacturing and mixed matrix structures have been produced using traditional manufacturing processes for various industrial applications due to their high mechanical properties to material weight and cost ratio. However implementation of composite and mixed matrix manufacturing with advanced manufacturing such as additive manufacturing is limited due to the hardware limitations of current 3d printing technologies and materials available for 3D printing applications. This work has developed and investigated a new hybrid 3D printing manufacturing process utilizing a variety of material systems (thermoplastic – thermoset, thermoplastic – thermoplastic, thermoset – thermoset, thermoplastic – thermoplastic – thermoset). This study developed thermoplastic …

Adaptive Robot Collaboration Using Robotic Skin And Motion Similarity., Jordan Dowdy

Electronic Theses and Dissertations

An essential part of robotics research is human-robot collaboration, which enables the use of current and new robots in everyday life and the workforce. This research applies to both parts of human-robot collaboration: physical human-robot interaction (pHRI), as well as non-physical human-robot interaction. The physical interaction uses tactile sensors and a Neuroadaptive Controller (NAC) to allow for the guidance of a robotic arm and its end-effector. The non-physical interaction uses a novel motion similarity metric, the Cartesian Segment Online Dynamic Time-Warping (SODTW), to allow a robot to better adapt to the speed of the user performing the motion during imitation …

Novel Sensors, Algorithms And Metrics For Human-Robot Interaction., Henry Lee Reynolds

Electronic Theses and Dissertations

The increased presence and deployment of robotics in sectors such as the medical field results in the demand for robots to, directly and indirectly, interface with people and their environment, making human-robot interaction (HRI) a vital thrust of robotics research. Assistive robots, for example, aid humans in accomplishing tasks or by providing support in the workforce. As the demand for nurses and the aging population increases, the assistive robots deployed will be deeply rooted in environments that require constant interaction with humans. This work contributed to improving aspects of HRI through 1) Expanding accessibility of the methods used for interfacing …

Lost In The (Re)Process: Challenging Constructions Of Downtown Louisville Through The Urban Renewal Commission Photograph Collection., Cassidy Meurer

Electronic Theses and Dissertations

This thesis chronicles the historical significance of the Urban Renewal Commission photograph collection, traces the history of racial capitalism in Louisville through research at Metro Louisville Archives & Records Center, and argues for alternative ways of organizing, digitizing, and presenting these archival materials in the University of Louisville’s Archives & Special Collections. I describe my methodology for breaking the photographic materials from their original order, going against typical archival processing methodologies, with the aim that the collection will more accurately represent the city’s strategic displacement of Black Louisvillians and civic prioritization of capital efficiency over community. This work emphasizes the …

Reinforcement Learning Assisted Communication Resources Optimization In Advanced Air Mobility., Ruixuan Han

Electronic Theses and Dissertations

Advanced air mobility (AAM), which envisages a safe and efficient aviation transportation system, has drawn significant attention to support the increasing mobility demand in metropolitan areas. Communication services for AAM aerial vehicles (AVs) are crucial for ensuring flight safety. This dissertation explores three research topics on communication resource allocation problems in AAM applications. The first topic, addressed in Chapter II, investigates the joint velocity selection and spectrum allocation problem for AAM applications to enhance spectrum utilization efficiency (SUE). In the AAM scenario, multiple AVs travel along predefined paths for passenger and cargo deliveries. Given that AAM aims to provide fast …

Interpretation Models For Prostate Lesion: Detecting, Explaining, And Understanding., Mehmet Akif Gulum

Electronic Theses and Dissertations

Prostate cancer is a major public health concern, affecting millions of men worldwide. While early detection and treatment of prostate cancer is critical for improving patient outcomes, the detection of prostate lesions is even more important for timely intervention and management of the disease. Prostate lesions are abnormal growths or lumps within the prostate gland, which may or may not be cancerous. The timely detection and accurate diagnosis of prostate lesions is crucial for effective treatment and management of the disease. In recent years, deep learning models have shown promise in accurately detecting and characterizing prostate lesions using advanced imaging …

Virtual Engagement: Can Law Enforcement Benefit From Utilizing Extended Reality In Their Training Systems?, Jacob Maxwell Read

Electronic Theses and Dissertations

Introduction: Extended reality (XR) technologies offer innovative training solutions for various industries, including healthcare, manufacturing, aviation, sports, military, and law enforcement. XR can provide a solution for training where job tasks are difficult or near impossible to train in real-life. A human factors research and design approach could provide an effective, low-risk, and cost and time-efficient option for integrating the use of XR technology into training for many industries. To advance this goal, this research answered two main research questions: (1) What training needs/challenges are best suited for an XR training system designed for law enforcement officers (LEOs)? (2) …

Examination Of Model Minority Myth, Mentorship, University Environment, And Sense Of Belonging On The Well-Being Of Asian American Undergraduate And Graduate Students., Stephanie Chin, Stephanie Chin

Electronic Theses and Dissertations

Even though Asian Americans continue to demonstrate academic excellence and have the highest rates of completion in higher education, their psychological well-being and the factors impacting it are often overlooked due to the model minority myth (Poon et al., 2016; Mahalingham, 2013). Higher education research mainly focuses on academic outcomes (e.g., persistence and retention) and less so on psychological outcomes. This study explored and examined psychosociocultural factors, specifically internalization of the model minority myth stereotype, mentorship, university environment, and sense of belonging on psychological (eudaimonic) well-being, in order to provide a more holistic and contextualized perspective of Asian American students’ …

Constant-Ph Molecular Dynamics At Inorganic Interfaces: Adding A New Dimension To Simulations Of Interfacial Phenomena., Ted Kalbfleisch

Electronic Theses and Dissertations

This dissertation explores the application of novel molecular dynamics simulation methods to better understand complex systems, with a particular focus on silica materials and protein interactions. Silica materials, known for their versatile surface and solution chemistries, play critical roles in catalysis, chromatography, and wastewater treatment. Despite their widespread use, the molecular-level interactions between silica surfaces and their environments remain poorly understood. To address this knowledge gap, we employed λ-dynamics enabled constant pH molecular dynamics to dynamically model protonation and deprotonation events on silica surfaces. Traditional experimental techniques such as x-ray crystallography, NMR, and cryo-EM are inadequate for probing structures in …

Manipulation Of Cellular Proliferating Cell Nuclear Antigen (Pcna) During Herpes Simplex Virus Type 1 Infection, Jessica Packard, Jill A. Dembowski

Electronic Theses and Dissertations

Herpes simplex virus type 1 (HSV-1) is a double stranded DNA virus that replicates within the nucleus of host cells. Using accelerated native isolation of proteins on nascent DNA (aniPOND), cellular proteins were found to associate with HSV-1 replication forks. One host factor of interest is proliferating cell nuclear antigen (PCNA), the DNA sliding clamp that tethers DNA polymerases and DNA damage response proteins to replicating cellular DNA. Although HSV-1 encodes its own DNA polymerase processivity factor (UL42), PCNA plays a key role in HSV-1 infection. We used commercially available PCNA inhibitors and short hairpin RNAs (shRNA) to investigate how …

Structure-Function Relationships In Neurodegenerative And Infectious Diseases: Biophysical Characterization Of Rna Secondary Structures By Computational Techniques, Kendy Guarinoni

Electronic Theses and Dissertations

The research described in this dissertation focuses on the investigation of the structure and dynamics of regions of RNA implicated in two diseases: COVID-19 and amyotrophic lateral sclerosis/frontotemporal dementia (ALS/FTD). Both studies sought to create experimentally corroborated models that were used to characterize the structure and dynamics of the C9orf72 repeat expansion and the s2m region in coronaviruses, respectively and provided the foundation for future work. In our work involving the s2m region of SARS-CoV-2, the virus responsible for COVID-19, we determined that the homology modeling approach commonly used to derive atomistic structures when no coordinates are available yields a …

A Descriptive Study: Aging In Place In The Rural Southeastern United States, Dama G. Cooley

Electronic Theses and Dissertations

Older Americans will soon outnumber children and younger adults. In 2022, there were 58 million older adults. By 2050, older adult numbers will grow to 82 million, and by 2060, 100 million. The National Institute on Aging calls for ongoing research on the impact that a historically large aging population will have on health, well-being, and quality of life. A key concern is how to meet needs while decreasing costs associated with institutional long-term care.

Most of these elders reside in the community and wish to live in their homes throughout their lives, but they will experience an increased need …

Bayesian Approaches In Multi-State Markov Models And High Dimensional Time-To-Event Data., Yuchen Han

Electronic Theses and Dissertations

This dissertation consists of two projects. The first one involves nonparametric methods on Continuous Time Markov Chains (CTMCs). The second one is centered around Bayesian shrinkage models for detecting prognostic and predictive biomarkers in high-dimensional clinical data. Both these projects build on methods from across the frequentist and Bayesian paradigm to offer novel solutions. In the first project, we aim to model the nonlinear effects of continuous variables within multistate framework in a non-parametrically by appealing to the rich mathematical framework of Reproducing Kernel Hilbert Spaces (RKHS). Then we adapted the classical Representer Theorem to penalized (squared norm) log-likelihood which …

Towards High Performance And Energy Efficient Data Centers., Bryan Harris

Electronic Theses and Dissertations

Our modern society has become ever more connected and reliant on ever larger quantities of data, which must be collected and processed over large geographic areas. The data centers that store, compute, and share this data have grown to such a scale that many data centers use as much electricity as a city. Priorities in research have shifted from not only seeking greater performance, but also towards greater energy efficiency. The control and management of computer systems has an impact on power consumption beyond the needs of individual components. In this dissertation, we examine techniques for improved performance and energy …

Denoising And Super-Resolution Of In-Vitro 4e Flow Mri In A Stenotic Phantom Model Using Physics-Informed Neural Networks., Shrouk M. Wally

Electronic Theses and Dissertations

In recent years, the use of 4D flow MRI has revolutionized cardiovascular imag- ing by providing comprehensive data on blood flow dynamics over time. However, the limited spatial and temporal resolution of this imaging modality can hinder the accurate assessment of complex hemodynamic phenomena. This thesis explores the application of Physics-Informed Neural Networks (PINNs) to enhance the resolution of 4D flow MRI data, thereby improving its clinical utility. PINNs are a class of neural networks that integrate physical laws into their training process. By embedding these physics equations, PINNs can discover the underlying physics of fluid dynamics to produce more …

Simulation Study On Confidence Interval Estimation For Standard Deviation With Non-Normal Distributions, Theophilus Oppong Kyeremeh

Electronic Theses and Dissertations

This study explores innovative approaches to constructing confidence intervals for the population standard deviation, σ, in non-normal data scenarios. While the sample standard deviation, s, is widely used, its reliability is compromised when dealing with skewed or heavy-tailed distributions and exhibits sensitivity to outliers. Our research addresses these limitations by investigating alternative estimation methods that offer greater robustness and accuracy.

Avian Communities Monitored Along A Successional Chronosequence In Bottomland Hardwood Forests In The Lower Mississippi Alluvial Valley, Eamonn Alasdair Thurmond

Electronic Theses and Dissertations

Bottomland hardwood forests in the Lower Mississippi Alluvial Valley have been extensively reduced due to agriculture conversion and altered hydrology. Remnant forests have undergone further degradation from sources such as a lack of forest management, invasive species, and reduced regeneration of oaks (Quercus spp.). Recent restoration efforts of bottomland hardwood forests have focused on implementing wildlife forestry practices that prioritize restoring wildlife habitat while retaining profitable timber harvests. In this study I surveyed bird communities in bottomland hardwood forests in the Lower Mississippi Alluvial Valley along a successional chronosequence. Birds were sampled using automated recording units over 10 days …