Digital Commons Network^™

Prognostic Modeling Of Recovery Following Stem Cell Transplantation, Brielle A. Forsthoffer

Theses and Dissertations

Predicting the trajectory of lymphoid recovery following myeloablative hematopoietic stem cell transplantation (SCT) can help guide subsequent therapeutic decisions, since poor recovery has been associated with graft-versus-host disease (GVHD), relapse and mortality. Previous attempts at classifying patients depended on absolute criteria being set prior to modeling absolute lymphocyte counts (ALCs) over time. Having an empirical clinical decision support tool for objectively determining the trajectory an individual might take during their recovery would be advantageous. We propose using growth-based trajectory modeling (GBTM) and growth mixture modeling (GMM), which utilize machine learning algorithms to empirically identify latent groupings of data. Due to …

Pharmacophoric Evaluation Of 5-Ht2a And 5-Ht2b Serotonin Recpeptors, Prithvi Hemanth

Theses and Dissertations

Serotonin (5-HT) receptors represent a class of receptors involved in a variety of physiological processes including regulation of mood, perception, cognition, appetite, and heart function, and thus serve as drug targets of several drugs such as antipsychotic agents, hallucinogenic drugs, and appetite suppressant drugs. Due to the structural similarity of certain 5-HT receptor subtypes, particularly 5-HT₂ receptors (5-HT_2A, 5-HT_2B receptors) determination and refinement of pharmacophore models of these receptor subtypes can greatly improve the therapeutic efficacy of drugs that target them.

The goals of this study were to define and/or refine existing pharmacophore models for 5-HT …

Intentions To Use Telerehabilitation For Communication And Treatment For Vision Impairments, Eric E. Hicks

Theses and Dissertations

BACKGROUND: Approximately 8.1 million people in the United States 18 and older have difficulty performing one or more daily activities because of vision impairment or blindness (Erickson, Lee, & von Schrader, 2020; Taylor, 2018). If the impairments caused by vision loss are not addressed, they can result in financial difficulties, suffering, disability, loss of productivity, and decreased quality of life (National Center for Chronic Disease Prevention and Health Promotion, 2011). Currently, in-person low vision rehabilitation services are the gold standard for teaching people how to adapt to and compensate for these deficits, however, the access and utilization of these services …

Sleep-Related Problems, Sleep-Related Distress, And Sleep-Related Functional Status Among Adult Inpatients Receiving Palliative Care, Lisa C. Sievers

Theses and Dissertations

Palliative care patients may be at a higher risk for sleep-related problems and their negative effects compared to the general population, yet limited sleep research has been done with this population. The purpose of this dissertation was to determine prevalence rates for excessive sleepiness, insomnia, restless legs syndrome (RLS), and high risk for sleep apnea (HRSA); examine relationships between the aforementioned sleep-related problems, sleep-related distress (SD), and sleep-related functional status (SFS); and to determine which sleep-related problem measures along with age and gender predicted SD and SFS among a sample of adult palliative care inpatients. Secondary aims were to understand …

A Deep Learning U-Net For Detecting And Segmenting Liver Tumors, Vidhya Cardozo

Theses and Dissertations

Visualization of liver tumors on simulation CT scans is challenging even with contrast-enhancement, due to the sensitivity of the contrast enhancement to the timing of the CT acquisition. Image registration to magnetic resonance imaging (MRI) can be helpful for delineation, but differences in patient position, liver shape and volume, and the lack of anatomical landmarks between the two image sets makes the task difficult. This study develops a U-Net based neural network for automated liver and tumor segmentation for purposes of radiotherapy treatment planning. Non-contrast simulation based abdominal CT axial scans of 52 patients with primary liver tumors were utilized. …

Dendrimer-Based Antibiotics For The Treatment Of Bacterial Biofilm In Cystic Fibrosis (Cf), Younan Ma

Theses and Dissertations

Pseudomonas aeruginosa (PA) is the predominant pathogen in chronic lung infections of cystic fibrosis (CF) patients. The most important mechanism of adaptation of PA to host defense and antibiotic treatment is the formation of biofilms within the mucus layer covering the lung bronchi. The effectiveness of antibiotics such as aminoglycosides is significantly attenuated by their limited penetration through thick mucus and embedded biofilm matrix in patients’ lung. Inhaled tobramycin (Tobra), which is the most commonly used antibiotics in the treatment of PA infections for CF patients, is usually found to be in very high concentration in patients’ lung, and yet …

Health Outcomes And Utilization Associated With Renal Diseases In Patients With Cancer In The United States, Mitisha Dedhia

Theses and Dissertations

Background: Adverse events and impairments associated with cancer and its treatments causes worse outcomes. Increased incidence of renal diseases among cancer patients is of particular concern. Objective: To determine the risk factors for renal disease in cancer patients and compare healthcare costs, utilization and health-related quality of life (HRQoL) of cancer patients with a renal disease and cancer patients without renal diseases. Methods: Medical Expenditure Panel Survey files from 2009 – 2018 for cancer patients was used for this study. Multiple logistic regression, generalized linear model, Poisson regression and multiple linear regression for analyses after adjusting for demographic, socioeconomic and …

Patient Blood Management Programs And Their Association With Patient And Organizational Outcomes, Sandra L. Lamm

Theses and Dissertations

Blood transfusions are the most common hospital procedure. However, many transfusions may be unnecessary. These unnecessary transfusion may expose patients to the potential risks of transfusion without improving patient outcomes Patient blood management (PBM) programs emphasize conserving a patient’s own blood resources and only transfusing the minimum amount needed. This study examined the organizational and environmental factors associated with a hospital having a PBM program, or having processes based on PBM, and their impact on organizational and patient outcomes potentially affected by blood transfusions.

A PBM survey was created for this study and used to gather information on hospitals having …

Examining The Impact Of Entrepreneurship Training On Entrepreneurial Mindset And Economic Well-Being, Sombo Muzata

Theses and Dissertations

This study used a mixed methods research design to examine the impact of entrepreneurship training on entrepreneurial mindset and economic well-being using the RVA Works Entrepreneurship Training Program as a case study. With human capital theory as a theoretical framework, a combination of 55 interviews and 36 surveys were used to answer the research questions. The study found that entrepreneurship training positively impacts an entrepreneurial mindset. The impact of the training on entrepreneurial mindset differed by participants age and educational level. Study participants applied their entrepreneurial mindset to their businesses, jobs, and other aspects of life. Participation in the program’s …

Physiological And Subjective Effects Of Protonated Nicotine Liquids In Tobacco Users, Alisha Eversole

Theses and Dissertations

Electronic cigarettes (ECIGs) produce an aerosol by heating a liquid that often contains nicotine. The nicotine can be protonated, potentially making the aerosol easier to inhale than freebase nicotine. This study’s purpose was to determine, in inhaled tobacco product users, the effects of three concentrations of protonated nicotine aerosolized at two different power settings (in watts).

Twenty-two participants completed six sessions that varied by liquid nicotine concentration (10, 15, or 30 mg/ml protonated nicotine) and device power (15 or 30 W). Participants took 10 puffs from each product and then used each product for 60 minutes ad libitum. Plasma …

Formulation, Characterization And Pharmacokinetic Modelling Of Excipient Enhanced Growth Spray-Dried Inhalation Powders, Serena Bonasera

Theses and Dissertations

The overall aim of this research project was to evaluate effects of spray drying parameters and storage conditions on solid-state characteristics and aerosol performance of excipient enhanced growth (EEG) powders and to formulate a stable and highly dispersible tobramycin EEG powder to be delivered to pediatric cystic fibrosis subjects using a novel positive pressure dry powder inhaler.

Micrometer-sized albuterol sulfate EEG powders were produced using a medium-sized nebulizer and optimized spray drying conditions. Using trileucine as the dispersion enhancer improved the aerosol performance but showed increased moisture absorption compared to the L-leucine formulation.

The optimized spray drying conditions were then …

A Spatiotemporal Assessment Of Fish Assemblage Response To Land-Use Change And The Evaluation Of Edna Metabarcoding For Describing Diverse Fish Communities, Timothy M. Owen

Theses and Dissertations

Fish assemblages are often assessed as a biological proxy for environmental health. While humans value healthy environments for the ecosystem services and recreational opportunities they provide, it is increasingly evident that such resources can be paradoxically degraded by anthropogenic activities. In this investigation, we studied the relationship between different intensities of anthropogenic land-use change and habitat-driven fish assemblage response across multiple spatiotemporal scales. Secondarily, we explored the efficacy of eDNA metabarcoding against conventional electrofishing techniques for the purpose of describing complete fish communities. This study was conducted in the Tuckahoe Creek basin near Richmond, Virginia. This James River tributary serves …

The Impact Of Healthcare Professional Students' Racial, Hiv-Related, And Abortion-Related Biases On Recommendations For Prenatal Care, Alison J. Patev

Theses and Dissertations

Black women and HIV-positive women have increased maternal mortality rates and other negative pregnancy outcomes, in part due to disparate prenatal care. Although women who seek abortions do not have the same negative outcomes, abortion stigma exists and is normalized in healthcare. Limited work has examined prenatal care provision for women in these groups, and even less work has explored the prenatal care provision by healthcare trainees (i.e., medical, nurse practitioner, and physician assistant students). Examining the role of bias on the prioritization of prenatal care items by healthcare trainees is imperative. Healthcare education sets the stage for future practice, …

Starting Earnings Of Bachelor’S And Advanced Degree Graduates By Field Of Study: Using Multi-Level Modeling To Estimate The Effects And Early Labor Market Consequences Of Vertical And Horizontal Dimensions Of Higher Education, Qiao Liang

Theses and Dissertations

This study was conducted to better understand early labor market outcomes of higher education and the importance of the vertical and horizontal dimensions of higher education. Using College Scorecard’s institution and field of study levels data and a multilevel modeling approach, it estimated and ranked typical starting earnings associated with a large spectrum of bachelor’s and advanced degree programs, and discussed patterns, variations, and irregularities observed in the ranked earnings. This study also calculated advanced degree effects on the typical starting earnings associated with bachelor’s and advanced degree programs, and set precedence to systematically compare the effects of major, department, …

Breaking The Cycle: A Longitudinal Study Of Factors That Disrupt Peer Selection And Influence Processes Among Urban Youth, Kelly E. Oconnor

Theses and Dissertations

Having friends who engage in problem behavior (i.e., aggression, substance use, delinquency) has consistently been linked to adolescents’ own engagement in problem behavior. There are, however, several key gaps in the literature on peer influence. Few studies have considered the influence of friends’ prosocial behavior and there has been limited research to identify promotive factors that influence urban youths’ affiliation with peers who engage in problem and prosocial behavior across early adolescence, a time of heightened susceptibility to peer influence. The purpose of this study was to identify modifiable promotive factors that reduce adolescents’ problem behavior by decreasing exposure to …

Alcohol Use Subgroups Among Rural Middle School Students: The Impact Of Community Violence Exposure, Courtney B. Dunn

Theses and Dissertations

A substantial portion of early adolescents initiate alcohol use. This represents a significant public health concern due to its association with a variety of adverse consequences. Although person-centered analytic approaches such as latent class analysis have been used to describe heterogeneity in adolescents’ alcohol use, most prior studies have focused on high school or older samples. This may obscure patterns of alcohol use that emerge during early adolescence. The current study identified and described subgroups of adolescents based on their alcohol use in a racially diverse sample of rural middle school students. Because research and theory indicate that exposure to …

Bayesian Techniques For Relating Genetic Polymorphisms To Diffusion Tensor Images Of Cocaine Users, Tmader Alballa

Theses and Dissertations

Past investigations utilizing Diffusion Tensor Imaging (DTI) have demonstrated that cocaine use disorder (CUD) yields white matter changes. We proposed three Bayesian techniques in order to explore the relationship between Fractional Anisotropy (FA), genetic data, and years of cocaine use (YCU). CUD participants exhibit abnormality in different areas of the brain versus non-drug using controls, which is measured by DTI. This dissertation is motivated by a neuroimaging genetic study in cocaine dependence, which found that there were relationships between several genes such as GAD and 5-HT₂R and CUD subjects.

In the first chapter, there is background on the …

Surface Characterization Of Accident Tolerant Fuel Claddings Candidates After Prolonged Exposure To Steam Oxidation, Connor F. Donlan

Theses and Dissertations

Accident Tolerant Fuel Claddings are designed to improve fuel performance and safety in abnormal reactor conditions. The development of these cladding materials has become a top priority for the nuclear community, with incidents such as the Three Mile Island accident and the Fukashima Dai-chi accident. The development of these claddings has resulted in 2 subsections: coating current claddings or replacing cladding materials with new materials. The claddings studied in this thesis are a Zircaloy-4 cladding coated with chromium through physical vapor deposition, Zircaloy-4, and a FeCrAl alloy, C26M. This thesis assessed the surface chemistry, roughness, and wettability after extended exposure …

Repair In An Economy Of Trauma: How Identifying Traumas As The Basis For Teacher Artmaking Contributes To Resiliency In Managing Traumatic Stress, Danielle R. Houdek

Theses and Dissertations

REPAIR IN AN ECONOMY OF TRAUMA:

HOW IDENTIFYING TRAUMAS AS THE BASIS FOR TEACHER ARTMAKING CONTRIBUTES TO RESILIENCY IN MANAGING TRAUMATIC STRESS

By Danielle Raddin Houdek, BFA, MAE

A thesis submitted in partial fulfillment of the requirements for the degree of Master of Art Education at Virginia Commonwealth University.

Virginia Commonwealth University, 2021.

Major Director: Dr. Sara Wilson-McKay

Associate Professor, Department of Art Education, School of the Arts

Objective: Through this research project, the impact that secondary traumatic stress has on art educators and how artmaking contributes to resiliency in managing secondary traumatic stress was examined. The research question is: …

Gender Equity Implications Of Nonprofit Youth Programs: Education Outcomes Of Three African American-Led Nonprofits, Yali Pang

Theses and Dissertations

Significant racial and gender differences in school performance have been a great concern in the past decades, and especially the significant differences in education performance between both Black youth and other racial groups and between Black males and Black females. Nonprofit youth programs are increasingly considered a promising intervention that can effectively improve Black youth development and education outcomes. While there is a growing body of literature evaluating the outcomes of nonprofit youth programs, little is known about gender differences in the outcomes, and specifically whether these nonprofit programs are equally effective for both Black males and females. This study …

Identification Of Four Residues Within The Tm4 Of The 5-Ht2a Receptor Necessary For 5-Ht2a·Mglu2 Heteromerization, John Mcginn

Theses and Dissertations

While the etiology is unknown, serotonin and glutamate G protein-coupled receptors (GPCR) neurotransmission dysfunctionality is characteristic of schizophrenia. Previous findings demonstrated that the serotonin 5-hydroxytryptamine 2A (5-HT_2A) receptor and the metabotropic glutamate 2 (mGlu2) receptor assemble into a heteromeric complex; however, little is known of the complete structural interface of the heteromer. Through a mutational-based approach, previous research identified Transmembrane domain 4 (TM4) as being responsible for mediating heteromerization in mGlu2 before determining the particular amino acids responsible for the interface. A similar technique was used in this investigation to determine which component of 5-HT_2A is responsible …

Interclass Gpcr Heteromerization Affects Localization And Trafficking, Rudy Toneatti

Theses and Dissertations

Class A serotonin (5-hydroxytryptamine) 2A (5-HT_2AR) and class C metabotropic glutamate 2 receptors (mGluR2) are seven transmembrane receptors (7TMRs or G protein-coupled receptors – GPCRs) involved in multiple neuropsychiatric disorders including schizophrenia. Previous findings from our laboratory reported that 5-HT_2AR and mGluR2 are dysregulated in the prefrontal cortex of patients suffering from this psychiatric condition, although 5-HT_2AR’s expression was recovered in antipsychotic-medicated patients. Genome-wide association studies on schizophrenia reported that endosomal trafficking that regulates cell surface abundance of another 7TMR implicated in this disease (dopamine D2 receptor) can be altered. Ligand-activated receptors, including the …

From Kindergarten Classrooms To Phd Pursuits: Academic Narratives That Influence Career Decisions In Black Women Counselor Education And Supervision Doctoral Students, Erin Hanley

Theses and Dissertations

Though Black women continue to receive advanced degrees at increased rates, this attainment is not reflected in the number of Black women serving as faculty members in academia. The field of counselor education encourages the recruitment and retention of diverse students and educators, though the literature outlining the reality of the experiences of Black women in counselor education has been limited. This qualitative interpretive phenomenological analysis uncovered the academic experiences of Black women doctoral students from kindergarten to their current doctoral programs, and how these experiences have influenced their career decision making. Guided by Black feminist thought and career human …

Threat Assessment Team Activity And Outcomes In K-12 Public Schools: Integrating Methods To Better Understand School Safety, Jessica C. Smith

Theses and Dissertations

The use of threat assessment teams in schools is recommended as a violence prevention measure in K-12 public schools. The present study focused on the threat assessment process in the K-12 environment in Virginia and is the first to examine the association between threat assessment and school safety in tandem over time and the first to incorporate the views of K-12 threat assessment practitioners. Findings from this study demonstrate that while the number of threat assessments has increased overtime, threat assessment practitioners identified numerous concerns regarding threat assessment training, expressed doubts about fidelity to the recommended process, and revealed an …

The Cb1 Receptor Positive Allosteric Modulator, Zcz011, Attenuates Naloxone-Precipitated Withdrawal Signs In Oxycodone-Dependent Mice And Inhibits Small Intestinal Transit In Mice, Julien Dodu

Theses and Dissertations

The endogenous cannabinoid system tightly regulates a myriad of physiological and pathophysiological functions. Effects of cannabinoids in ameliorating opioid withdrawal signs has been known for decades. Naloxone precipitates several withdrawal signs (e.g., diarrhea, weight loss, jumps, paw flutters, and head shakes) in opioid dependent rodents. ∆⁹-tetrahydrocannabinol (THC) has been shown to ameliorate opioid withdrawal in mice through the activation of cannabinoid type-1 (CB₁) receptors. Inhibition of the endocannabinoid degradative enzymes also attenuates these withdrawal signs (i.e., diarrhea, weight loss, jumps, paw flutters, and head shakes) in opioid-dependent mice. Specifically, inhibition of fatty acid amide hydrolase (FAAH), …

Sickle Cell Disease Associated Lipid Changes And Their Relevance Towards The Disease Pathogenesis And Lipid Biomarkers And Embryo Quality In In Vitro Fertilization; Pregnancy Success Differentially Expressed By Body Weight, Suad Alshammari

Theses and Dissertations

Abstract

Sickle cell disease (SCD) is a group of genetic disorder that occurs due to genetic mutation of a beta-globin gene that lead to production of pathogenic hemoglobin S (HB S). Genotypes of SCD include Hb SS (sickle cell anemia) which is the most common and severe form of SCD affects about 20 to 25 million people worldwide, HbSC, Hb Sβ+- thalassemia, and Hb Sβ0-thalassemia. SCD is characterized by multiorgan complications that, in turn, affect lipids composition. During hypoxia a sequence of changes will take place such as HbS polymerization, erythrocyte rigidity and stickiness, and oxidative stress. The combination of …

Behavioral And Quantitative Electroencephalogram Alterations During The Whisker Nuisance Task Following Mild Traumatic Brain Injury In Mice, David Wildman

Theses and Dissertations

Mild traumatic brain injury (mild TBI) has been shown to cause an array of symptoms in individuals lasting up to several years. Several publications have lead researchers to believe that parvalbumin axotomy and its associated changes with gamma oscillations may be the driving force for these symptoms. Several publications have demonstrated alterations in both resting gamma and evoked gamma by way of parvalbumin dysfunction. Our research analyzed resting and evoked gamma obtained by electroencephalograms (EEG) in nine mild TBI mice and six SHAM mice by utilizing a behavioral test known as the Whisker Nuisance Task (WNT). The central fluid percussion …

Nebulizer-Based Systems To Improve Pharmaceutical Aerosol Delivery To The Lungs, Benjamin M. Spence

Theses and Dissertations

Combining vibrating mesh nebulizers with additional new technologies leads to substantial improvements in pharmaceutical aerosol delivery to the lungs across therapeutic administration methods. In this dissertation, streamlined components, aerosol administration synchronization, and/or Excipient Enhanced Growth (EEG) technologies were utilized to develop and test several novel devices and aerosol delivery systems. The first focus of this work was to improve the poor delivery efficiency, e.g., 3.6% of nominal dose (Dugernier et al. 2017), of aerosolized medication administration to adult human subjects concurrent with high flow nasal cannula (HFNC) therapy, a form of continuous-flow non-invasive ventilation (NIV). The developed Low-Volume Mixer-Heater (LVMH) …

The Importance Of Connection: Contributions Of Relationships With Fathers And Connections To School To Delinquent Behavior And Positive Youth Development, Colleen S. Walsh

Theses and Dissertations

Risk-taking and boundary pushing are hallmarks of adolescent behavior, making the identification of promotive and protective factors related to both delinquent behavior and positive adolescent functioning essential. Previous studies have provided compelling evidence that suggests aspects of familial relationships may successfully attenuate delinquent behavior and support positive functioning outcomes. Despite these findings, the father-adolescent relationship is understudied in association with these outcomes. The current study examined relations between adolescents’ perception of school connectedness and father-adolescent relationship quality and delinquent behavior and positive adolescent functioning outcomes. This study used data collected when youth were nine and fifteen years old from the …

Associations Between Social Determinants Of Health And Chlamydia Infections Among Georgia Counties, Bre'auna K. Beasley

Theses and Dissertations

Chlamydia is a growing public health concern that disproportionately impacts southern states. While social determinants of health are not direct causes of chlamydia infections, studies have found that these determinants do influence infections by creating environments that promote or hinder health seeking behaviors, as well as exposure to risk factors. Guided by the Social Ecological Model of Public Health and the Healthy People 2030 Social Determinants of Health Conceptual Framework, this dissertation study aimed to examine the associations between social determinants of health and chlamydia infections among Georgia counties. This study employed a correlational research design. Aggregate-level secondary data for …