Digital Commons Network^™

Role Of Histone Deacetylase (Hdac) In Epithelial To Mesenchymal Transition (Emt) In A Human Cholangiocyte Model Of Ischemic Cholangiopathy, Priyanshi Pragnesh Parikh

Theses and Dissertations

Organ transplants are a vital intervention for many diseases that result in end stage organ failure. Currently, the donation pool is not meeting the demands of the transplant list. Expanding this pool to include donation after cardiac death (DCD) is highly sought-after. However, the use of DCD livers can lead to increased odds of graft failure and ischemic cholangiopathy. The loss of epithelialization and fibrosis that occurs during ischemic cholangiopathy is characteristic of these cells undergoing epithelial-to-mesenchymal transition (EMT). The biological changes the cell experiences enhance migratory capacity, invasiveness, and increased resistance to apoptosis. Our earlier studies have shown differential …

Mechanisms Of Emulsion Destabilization: An Investigation Of Surfactant, Stabilizer, And Detergent Based Formulations Using Diffusing Wave Spectroscopy, Jordan N. Nowaczyk

Theses and Dissertations

Conventional approaches for studying emulsions, such as microscopy and macroscopic phase tracking, present challenges when it comes to establishing detailed mechanistic descriptions of the impact of emulsifier and stabilizer additives. Additionally, while a combination of sizing methods and macroscopic phase tracking can provide insights into droplet size changes and concentration, the use of multiple measurements can be cumbersome and error-prone. It is the focus of this work, to present a new method for studying water in oil (W/O) emulsions that involves using diffusing wave spectroscopy (DWS) to examine the impact of three different surface stabilizing additives at varying concentrations. By …

Investigating Actor Speech Training History Through The Lens Of Knight-Thompson Speechwork: How A Nonprescriptive Approach Revolutionizes The Field And Applications Outside Of A Theatrical Context, Harrison G. Runion

Theses and Dissertations

Speech training for actors in the United States has a history deeply rooted in prescriptive practices. Many speech trainers have and still do teach from a model that they consider to be the “correct” way to speak. These practices have proven to be quite damaging to students’ emotional and cultural identities, as speech is an inherent part of who we are as individuals. This thesis first examines such speech training pedagogies of the past, specifically the progression of William Tilly’s World English to Edith Skinner’s Good American Speech. Doing so establishes the necessary contextual understanding required to provide an alternative …

Characterization And Investigation Of Cold Atmospheric Plasma And Its Effects On Cancer Cell Biology, Thomas M. Ritrosky

Theses and Dissertations

Modern cancer treatment uses radiation therapy in over 50% of patient cases. It is an e↵ective way of treating tumors because the mechanisms of cell killing are well known through the damage that ionizing radiation does to DNA. The amount of radiation can be tracked through measuring the dose of the clinical photon or electron beam used. However, there are limitations in the usage of radiation therapy, for example, a tumor can create hypoxic areas that become radioresistant leading to complete ine↵ectiveness of further radiation treatment. This project looks into the application of cold atmospheric plasma as an adjuvant therapy …

Epithelial Membrane Protein 3 (Emp3b) Is A Novel Regulator Of Sympathetic Nervous System Development In Zebrafish., Jessica M. White

Theses and Dissertations

Notable progress has been made in understanding the development of the neural crest (NC). Neural crest cells (NCCs) can be divided into 4-5 subpopulations. A major lineage among trunk NC derivatives are sympathoadrenal (SA) cells, which give rise to the sympathetic nervous system (SNS). Trunk NCCs follow a ventromedial migration pathway where signals derived from the dorsal aorta instruct migrating NCCs to a SA cell fate. Defects in NC development can result in syndromes known as neurocristopathies. Neuroblastoma is one of the most common forms of pediatric cancer affecting nearly 800 infants each year in the United States (Takita et …

Sinonasal Outcomes Using Oral Corticosteroids In Patients With Chronic Rhinosinusitis With Nasal Polyps And Positive Sinonasal Cultures, Jhon F. Martinez Paredes, Angela M. Donaldson, Michael Marino, Garret Choby, Osarenoma Olomu, Razan Alfakir, Janalee K. Stokken, Erin O'Brien, Devyani Lal

School of Medicine Publications

Introduction: Patients with chronic rhinosinusitis with nasal polyps (CRSwNP) and positive sinonasal bacterial cultures may be recalcitrant to topical therapy alone due to the additional local inflammatory burden associated with bacterial infection/colonization.

Objective: To evaluate sinonasal outcomes in CRSwNP patients with a positive perioperative bacterial culture, who were treated with postoperative intranasal corticosteroids (INCS) alone versus INCS in combination with a short-term course of oral corticosteroids (OCS).

Methods: This is a retrospective chart review of CRSwNP patients. A total of 59 patients met inclusion criteria, including positive perioperative bacterial culture and treatment with INCS with or without concomitant use of …

Sleep And Health Behaviors In A Safety-Net Primary Care Setting, Sahar Sabet

Theses and Dissertations

Nearly half of all premature deaths in the United States are attributable to preventable and modifiable health risk behaviors. For decades, the leading behavioral health contributors to morbidity and mortality are tobacco use, physical inactivity, and alcohol consumption. Medication adherence is a relatively less studied yet critical interrelated health behavior that is tied to health and treatment outcomes. Sleep, an important pillar of health, is a daily and modifiable behavior that shows promise as a health behavior facilitator. Better understanding the dynamics of these modifiable health behaviors is essential for the improvement of health promotion, particularly among underserved populations (e.g., …

Evaluating The Acute Effect Of Vaping On Food Intake, Gabrielle Maldonado

Theses and Dissertations

Background: Weight control is a common motive for continued cigarette smoking, and weight concerns pose a barrier to quitting. These effects are driven in part by nicotine’s ability to reduce overall appetite and ultimately body weight. Electronic nicotine delivery systems (ENDS) have been marketed and used for weight control, suggesting that the use of these products potentially may share similar effects as well as barriers to quitting as observed for cigarette smoking. However, little to no controlled clinical lab evidence exists supporting ENDS use for weight control. The present study tested the influence of an ENDS on acute eating behavior …

A Learning Health System For Radiation Oncology, Rishabh Kapoor

Theses and Dissertations

The proposed research aims to address the challenges faced by clinical data science researchers in radiation oncology accessing, integrating, and analyzing heterogeneous data from various sources. The research presents a scalable intelligent infrastructure, called the Health Information Gateway and Exchange (HINGE), which captures and structures data from multiple sources into a knowledge base with semantically interlinked entities. This infrastructure enables researchers to mine novel associations and gather relevant knowledge for personalized clinical outcomes.

The dissertation discusses the design framework and implementation of HINGE, which abstracts structured data from treatment planning systems, treatment management systems, and electronic health records. It utilizes …

Exploring Polyamorous Relationship Experiences Of Lesbian, Gay, Bisexual, And Pansexual Individuals, Jiale Man

Theses and Dissertations

Polyamory is a type of relationship under the consensual non-monogamy relationship umbrella that assumes the possibility, validity, and worthwhileness of maintaining romantic, sexual, and intimate relationships with multiple people simultaneously. In Western society, the prevalence and domination of mononormativity have led to the marginalization of relationships alternative to monogamy (i.e., polyamory). As a result, individuals in polyamorous relationships continue to experience bias, stigma, and discrimination at varying levels. With a rise in public interest in CNM in the past two decades, scientists and researchers have slowly started to examine various topics related to CNM, including its prevalence, public attitudes toward …

Exploring The Relationship Between The Epigenome And Metabolism In Mycn-Amplified Neuroblastoma, Krista M. Dalton

Theses and Dissertations

High risk neuroblastoma (NB) is responsible for nearly 15% of all cancer related deaths in the pediatric population. The transcription factor MYCN is the most studied oncogene in NB, automatically conferring high-risk and has been found to be difficult to target. One way that MYCN amplification in NB functions to support tumorigenicity is through altered metabolism, satisfying the demand for rapid proliferation by increasing the nutrient flux through biosynthetic pathways. We performed an unbiased screen on select metabolic targeted therapy combinations and correlated sensitivity with over 20 subsets of cancer. We found that MYCN-amplified NB is hypersensitive to the …

Machine Learning Models To Automate Radiotherapy Structure Name Standardization, Priyankar Bose

Theses and Dissertations

Structure name standardization is a critical problem in Radiotherapy planning systems to correctly identify the various Organs-at-Risk, Planning Target Volumes and `Other' organs for monitoring present and future medications. Physicians often label anatomical structure sets in Digital Imaging and Communications in Medicine (DICOM) images with nonstandard random names. Hence, the standardization of these names for the Organs at Risk (OARs), Planning Target Volumes (PTVs), and `Other' organs is a vital problem. Prior works considered traditional machine learning approaches on structure sets with moderate success. We compare both traditional methods and deep neural network-based approaches on the multimodal vision-language prostate cancer …

Association Of Interpersonal Trauma And Polygenic Risk Scores With Depressive Symptoms In College Students, Rowan K. O'Hara

Theses and Dissertations

Major depression is considered a complex trait influenced by both polygenic risk factors and environmental exposures, such as childhood trauma. This study applied statistical genetic methods to calculate aggregate genetic risk for major depression to predict depressive symptoms scores in a college student sample. Data were from the Spit for Science (S4S) study in which college students from a large urban university self-reported interpersonal trauma (IPT) exposure prior to college and depressive symptoms from the past month (N = 7502; ancestry group: 20% African [AFR], 12% Admixed Americas [AMR], 10% East Asian [EAS], 49% European [EUR], 8% South Asian [SAS]). …

Selected Problems In Graph Coloring, Hudson Lafayette

Theses and Dissertations

The Borodin–Kostochka Conjecture states that for a graph G, if ∆(G) ≥ 9 and ω(G) ≤ ∆(G) − 1, then χ(G) ≤ ∆(G) − 1. We prove the Borodin–Kostochka Conjecture for (P5, gem)-free graphs, i.e., graphs with no induced P5 and no induced K1 ∨P4.

For a graph G and t, k ∈ Z+ at-tone k-coloring of G is a function f : V (G) → [k] such that |f(v) ∩f (w)| < d(v,w) for all distinct v, w ∈ V(G). The t-tone chromatic number of G, denoted τt(G), is the minimum k such that G is t-tone k-colorable. For small values of t, we prove sharp or nearly sharp upper bounds on the t-tone chromatic number of various classes of sparse graphs. In particular, we determine τ2(G) exactly when mad(G) < 12/5 and also determine τ2(G), up to a small additive constant, when G is outerplanar. Finally, we determine τt(Cn) exactly when t ∈ {3, 4, 5}.

Enhancing Neuromorphic Computing With Advanced Spiking Neural Network Architectures, Paolo Gabriel Alejandro Cachi Delgado

Theses and Dissertations

This dissertation proposes ways to address current limitations of neuromorphic computing to create energy-efficient and adaptable systems for AI applications. It does so by designing novel spiking neural networks architectures that improve their performance. Specifically, the two proposed architectures address the issues of training complexity, hyperparameter selection, computational flexibility, and scarcity of neuromorphic training data. The first architecture uses auxiliary learning to improve training performance and data usage, while the second architecture leverages neuromodulation capability of spiking neurons to improve multitasking classification performance. The proposed architectures are tested on Intel's Loihi2 neuromorphic chip using several neuromorphic datasets, such as NMIST, …

Quantifying Fibronectin Mechanical Properties Using Antibody-Mediated Optical Tweezing (Amot), Caleb Dalton

Theses and Dissertations

Despite decades of investigations into fibronectin (FN) fibrillogenesis, fibril mechanics remain unclear. One of the most important roles for FN fibrils is in the arena of cellular mechanotransduction. Numerous studies have demonstrated that cells sense and respond to the mechanical properties of their surroundings; since FN fibrils are a major constituent of the ECM that links cells to their surroundings, mechanotransduction cannot be fully understood without understanding the mechanical properties of FN fibrils. In this proposal, a novel biomechanical assay is developed to probe isolated FN fibrils and quantify their response to specific loading conditions. This will be accomplished by …

Community On Campus: Examining The Impact Of Campus Climate, Belonging, And Flourishing On Bystander Behavior Among Diverse University Students, Amelia Liadis

Theses and Dissertations

This exploratory, nonexperimental study aimed to investigate the relationships among diverse undergraduate and graduate students’ perceived campus climate, flourishing, and university belonging on bystander intentions and bystander behaviors during the COVID-19 pandemic. The study’s theoretical framework combined the Theory of Planned Behavior and feminist theory, and examined intersectionality through an Identity Risk Index. Data used in the current study were originally collected as part of an institutional Healthy Minds Survey, on health behaviors of college students; responses from n = 171 of the randomly selected participants were used in the current study’s analyses. The majority of participants indicated at least …

Effects Of Slip On Highly Viscous Thin-Film Flows Inside Vertical Tubes (Constant Radius, Constricted And Flexible), Mark S. Schwitzerlett

Theses and Dissertations

Viscous liquid film flows in a tube arise in numerous industrial and biological applications, including the transport of mucus in human airways. Previous modeling studies have typically used no-slip boundary conditions, but in some applications the effects of slip at the boundary may not be negligible. We derive a long-wave model based on lubrication theory which allows for slippage along the boundary. Linear stability analysis verifies the impact of slip-length on the speed, growth rate, and wavelength of the most unstable mode. Nonlinear simulations demonstrate the impact of slip-length on plug formation and wave dynamics. These simulations are conducted for …

Virtual Plc Platform For Security And Forensics Of Industrial Control Systems, Syed Ali Qasim

Theses and Dissertations

Industrial Control Systems (ICS) are vital in managing critical infrastructures, including nuclear power plants and electric grids. With the advent of the Industrial Internet of Things (IIoT), these systems have been integrated into broader networks, enhancing efficiency but also becoming targets for cyberattacks. Central to ICS are Programmable Logic Controllers (PLCs), which bridge the physical and cyber worlds and are often exploited by attackers. There's a critical need for tools to analyze cyberattacks on PLCs, uncover vulnerabilities, and improve ICS security. Existing tools are hindered by the proprietary nature of PLC software, limiting scalability and efficiency.

To overcome these challenges, …

Developing Novel Femtosecond Time-Resolved Mass Spectrometry Techniques For Analysis Of Energetic Materials, Shane L. Mcpherson

Theses and Dissertations

Energetic materials and the unimolecular dissociation dynamics attributed to their initiation and subsequent bimolecular detonation have been a subject of interest for defense agencies such as the Department of Defense (DoD) for decades. The timescale in which these initial dynamics exist ranges from several picoseconds to dozens of femtoseconds, necessitating equally fast time-resolved experiments to capture and characterize these events. Our lab specializes in one such laser-based technique: femtosecond time-resolved mass spectrometry (FTRMS). FTRMS is an essentially nondiscriminatory pump-probe laser technique with nearly infinite modifications via pulse shaping, intensity, and wavelength modulation that can readily examine previously undefined dissociation pathways …

Reassessing Replication: Addressing The Replication Crisis From A Statistical Perspective, Alicia Richards Phd

Theses and Dissertations

In 2015, Open Science Framework directly replicated 100 psychology studies and found astonishingly low replication rates. Since, researchers have suggested factors that may have influenced the low rates, including the metrics used to assess replications. The definitions used to decide whether a replication study was successful all suffer from flaws. Therefore, we propose a new metric for assessing replication that can estimate the likelihood a study successfully replicated rather than forcing a binary choice and accounts for study design limitations.

Using equivalence study techniques, we first propose a new metric to assess replication, defining a successful replication as one where …

Thermal Performance And Fluid Flow Studies Of Twisted Tape Inserts Using Scaled Surrogate Fluids For Molten Salt Energy Applications, Arturo Cabral

Theses and Dissertations

Global energy consumption is expected to increase with population growth and innovative clean sources of energy are sought out that can help meet the needs of a continuously power-hungry world. Some of these innovative sources of energy use molten salts as their operating and cooling fluid, such as fission reactors, fusion reactors, and solar power with energy storage. Molten salts are considered due to their efficient heat transfer properties, thermal energy storage capabilities, and high operating temperatures. To expedite their deployment, a further understanding of the heat transfer systems is required to accurately design and develop the heat transfer components …

Protacs – A Novel And Rapidly Developing Field Of Targeted Protein Degradation, Hannah R. Gatley

Theses and Dissertations

There is a continued need for new technology and strategies for tackling cancer and other diseases, and within the current century a novel therapeutic strategy has emerged in the realm of targeted protein degradation called Proteolysis-Targeting Chimeras (PROTACs). This technology specifically targets and degrades disease-causing proteins via the ubiquitin-proteasome system, and has seen an explosion of research and intrigue in both academia and industry over the past two decades. The diversity of PROTAC classes based on the E3 ligase recruiting ligand and the target protein allows for a universal molecular structure that can be customized for a specific target and …

Transcriptional Coregulation Among Diabetes-Associated Pathways By Genome Organization, Musaddiq K. Lodi

Theses and Dissertations

There are currently 96 million individuals affected by diabetes in the United States alone. Crucial information such as biomarkers, regulatory networks, and metabolic pathways in diabetes still remain an active area of research. The primary focus of this study is on a phenomena known as transcription factor co-regulation. Transcription factors (TFs) are DNA-binding proteins that can control the rate of transcription of genetic information from DNA to mRNA, hence misregulation of one of them can lead to misregulation of many of its target genes and associated pathways. In this study I propose a framework to quantify transcriptional coherence in co-regulated …

Exploration Of Dimensional Structure Of Major Psychiatric Disorders Reveals Relationship With Substance Use And Personality, Noah Berley

Theses and Dissertations

Objective: Using a mixture of statistical techniques like structural equation modeling, confirmatory, and exploratory factor analyses, we aimed to determine the genetic factor structure among Externalizing, Internalizing, and Psychotic spectrum disorders through methods that evaluate GWAS-based correlations. Additionally, a subsequent factor analysis based on the most suitable psychiatric model was conducted to understand how non-clinical behavioral traits align with this factor structure.

Methods: Publicly available GWAS summary statistics for twelve major psychiatric disorders, six substance use measures and two personality domains were incorporated into structural equation models. Using the GenomicSEM software package, GWAS-based correlations were estimated between all twelve disorders …

Examining The Home Interventionist Model Of Care In Pediatric Asthma, Katherine D. Lohr

Theses and Dissertations

Pediatric asthma disproportionately affects children living in urban areas and within families reporting an income below the poverty threshold. Home interventionist models of care, utilizing interventionists from the communities they serve, have been found to improve pediatric asthma symptoms and reduce Medicaid costs. Home interventionists, such as community health workers (CHWs) and Healthy Homes assessors (HHAs), focus on connecting care among schools, providers, and homes, and empowering families in accessing resources to overcome barriers to care. However, research is just beginning to understand how home interventionists create positive change among families within low-income, urban communities. This dissertation study used a …

Evaluation Of Spliceai For Improved Genetic Variant Classification In Inherited Ophthalmic Disease Genes, Melissa Reeves

Theses and Dissertations

ABSTRACT

EVALUATION OF SPLICEAI FOR IMPROVED GENETIC VARIANT CLASSIFICATION IN INHERITED OPHTHALMIC DISEASE GENES

By Melissa Jean Reeves, Ph.D.

A dissertation submitted in partial fulfillment of the requirements for the degree of Doctor of Philosophy at Virginia Commonwealth University.

Virginia Commonwealth University, 2023

Major Director: Melissa Jamerson, PhD, MLS(ASCP)

Associate Professor, Department of Medical Laboratory Sciences

Inherited ophthalmic diseases impact individuals around the globe. Inherited retinal diseases (IRDs) are the leading cause of blindness in individuals aged 15 to 45. The personal, social, and economic impact of vision loss is profound. Due to individual differences, symptoms can be variable, and …

Face Anti-Spoofing And Deep Learning Based Unsupervised Image Recognition Systems, Enoch Solomon

Theses and Dissertations

One of the main problems of a supervised deep learning approach is that it requires large amounts of labeled training data, which are not always easily available. This PhD dissertation addresses the above-mentioned problem by using a novel unsupervised deep learning face verification system called UFace, that does not require labeled training data as it automatically, in an unsupervised way, generates training data from even a relatively small size of data. The method starts by selecting, in unsupervised way, k-most similar and k-most dissimilar images for a given face image. Moreover, this PhD dissertation proposes a new loss function to …

Improving The Performance, Energy Efficiency And Security Of Gpus, Xin Wang

Theses and Dissertations

The work in this dissertation achieves to enhance the performance, energy-efficiency, and security of the GPUs. We noticed that, as the demand of hardware resources keeps rising in GPUs, the energy consumption becomes unaffordable and places barriers for further performance boost. To resolve this issue, we have proposed several novel GPU micro-architectures that are able to assist the GPUs to execute in an energy-efficient manner. They also provide the potential for further performance enhancement in GPUs. Firstly, we proposed a GPU register packing scheme that stores multiple narrow-width operands to a single register to save register file resources. The unoccupied …

Effectiveness Of Financial Incentives In Improving Breast Cancer Screening Among Medicaid Recipients, James B. Sherwood

Theses and Dissertations

Breast cancer remains one of the leading causes of death among women. Roughly 2.4 million women are diagnosed annually with breast cancer throughout the world. Although breast cancer survival rates are favorable for the United States compared to other nations (90% 5-year survival for non-metastatic disease), it comes at a high cost. The United States spends an estimated $30 billion annually on breast cancer treatment. In addition, disparities in breast cancer survival rates also exist in the United States. Women Medicaid recipients, who are predominately minorities (60%), are more likely to die of breast cancer due to their high rates …