Digital Commons Network^™

The Prevalence, Predictive Factors, And Classification Of Intrapulpal Cracks In Maxillary Molars Requiring Endodontic Treatment, Husain Karashi

Theses and Dissertations

Diagnosis and treatment of teeth with longitudinal fractures is challenging. Cracks are usually not visible radiographically; they require a thorough evaluation to aid in diagnosis. Patients may be asymptomatic, demanding the dentist rely on clinical findings to make a diagnosis. Early diagnosis of the presence and extent of a crack is essential for the successful management of a cracked tooth. There is limited information in the literature regarding the prevalence or predictive factors of cracks extending into the pulp chamber of teeth. The purpose of this study was to determine the prevalence of intrapulpal cracks in maxillary molars and to …

The Impact Of Perceived Mental Illness Stigma On Caregivers’ Desire To Relinquish Care, Tyler R. Corson

Theses and Dissertations

Caregiving can be stressful, and older adults’ health and well-being may be impacted by the roles and responsibilities they assume as caregivers for persons with serious mental illness (SMI). This study is the first to apply the Stress Process Model of Caregiving (SPM) in an attempt to understand how mental illness stigma influences caregiver outcomes, specifically their desire to relinquish care. The intent of this study was to call attention to care relinquishment as an under-studied stress process outcome and to explore stress factors, with a focus on mental illness stigma, that contribute to SMI caregivers’ desire to relinquish care. …

Testing The Ability Of Two Series Of Models To Predict High School Graduation Status, David T. Marshall

Theses and Dissertations

The purpose of this study was to create and test two series of predictive models aimed at projecting high school graduation status. Secondary data were obtained in partnership with an urban school district. All of the predictor variables included in the models tested in this study were academic and nonacademic variables that were found to be significant predictors of high school graduation in previous empirical work. In the first series of models tested, individual academic and nonacademic variables were tested together along with school-level variables. Eighth and ninth grade variables were tested separately to avoid multicollinearity issues. The second series …

The Influence Of Genetic And Environmental Factors On Quit Attempt In Adolescent And Young Adult Twins, Gladys Langi

Theses and Dissertations

The purpose of this study was to examine the genetic and environmental influences on lifetime quit attempt in three US adolescent and young adult twin samples (N total = 6,322). The study utilized a common-contingent-causal (CCC) model to estimate these factors for lifetime quit attempts, after accounting for the factors for lifetime cigarette use and cigarettes per day. The study also examined age and sex differences, as well as the degree of relationship between these smoking phenotypes. The results demonstrated significant genetic influences for lifetime quit attempts in adolescents and young adults. No sex differences were observed for the contributions …

Profiling Precursor Lipids For Specialized Pro-Resolution Molecules In Platelet-Rich Fibrin Following Fish Oil And Aspirin Intake, Danielle M. Mccormack

Theses and Dissertations

Background: Current research has demonstrated that aspirin and fish oil (EFA) increase plasma levels of specialized pro-resolution molecules (SPMs). This study investigates their effects on SPM precursor pools in platelet rich fibrin (PRF). Methods: Twenty healthy volunteers were randomly assigned to take aspirin; EFA or aspirin and EFA. Four hours later, SPM precursor levels were quantified using combined Liquid Chromatography tandem mass spectrometry. The differences between the groups: Aspirin (yes or no), EFA (yes or no), were analyzed by ANCOVA, testing for group differences after covarying out the baseline value. Results: There were 4 significant interactions, 1 with an aspirin …

Profiling Precursor Lipids For Specialized Pro-Resolution Molecules In Platelet-Rich Plasma Following Fish Oil And Aspirin Intake, Lisa A. Turner

Theses and Dissertations

Background: Unfavorable outcomes following periodontal surgeries can be attributed to impaired resolution mechanisms likely due to decreased levels of specialized pro-resolution molecules (SPM). The current study investigates if SPM substrate pools in platelet-rich plasma preparations (PRP) can be increased by essential fatty acid (EFA) and / or aspirin supplementation. Methods: Nineteen healthy volunteers were randomly assigned to take i) aspirin; ii) EFA; iii) aspirin and EFA. Four hours after intake, the lipid precursor pools in PRP were quantified using combined Liquid Chromatography tandem mass spectrometry (LC-MS/MS) and the data statistically analyzed using ANCOVA. Results: Of the 77 metabolites screened, only …

Weighted Quantile Sum Regression For Analyzing Correlated Predictors Acting Through A Mediation Pathway On A Biological Outcome, Bhanu M. Evani

Theses and Dissertations

Abstract

Weighted Quantile Sum Regression for Analyzing Correlated Predictors Acting Through a Mediation Pathway on a Biological Outcome

By

Bhanu M. Evani, Ph.D.

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

Virginia Commonwealth University, 2017.

Major Director: Robert A. Perera, Asst. Professor, Department of Biostatistics

This work examines mediated effects of a set of correlated predictors using the recently developed Weighted Quantile Sum (WQS) regression method. Traditionally, mediation analysis has been conducted using the multiple regression method, first proposed by Baron and Kenny (1986), which has since …

An Investigation Of Surface Characteristics Of Enamel Treated With Infiltrative Resin: A Scanning Electron Microscopy Study, Danielle E. Easterly

Theses and Dissertations

AN INVESTIGATION OF SURFACE CHARACTERISTICS OF ENAMEL TREATED WITH INFILTRATIVE RESIN: A SCANNING ELECTRON MICROSCOPY STUDY

Danielle E. Easterly, Doctorate of Dental Surgery.

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

Virginia Commonwealth University. 2017.

Director: Dr. Eser Tüfekçi

D.D.S., M.S., Ph.D., M.S.H.A.

Objective: To evaluate the microstructural changes of a resin infiltrant (ICON®, DMG America LLC, Englewood, NJ) after six months of simulated toothbrushing.

Materials and Methods: Ten extracted third molars (n=10) were collected. Artificial white spot lesions were created and resin applied. Environmental SEM …

Work-Related Musculoskeletal Disorders Among Dentists And Orthodontists, Natalie R. La Rochelle

Theses and Dissertations

WORK-RELATED MUSCULOSKELETAL DISORDERS AMONG DENTISTS AND ORTHODONTISTS

A thesis submitted in partial fulfillment of the requirements for the degree of

Master of Science in Dentistry at Virginia Commonwealth University.

by

Natalie R. La Rochelle

Thesis Director: Dr. Eser Tüfekçi, D.D.S., M.S., Ph.D., M.S.H.A.

Professor, Department of Orthodontics

Virginia Commonwealth University

Richmond, Virginia

May 2017

The practice of dentistry is physically demanding due to static and dynamic postures sustained daily throughout careers. Previous literature suggests that work-related musculoskeletal disorders (WMSD) are not solely the result of work habits, but also due to the individual, his or her physical makeup, genetics, and …

Finding Voice, The Body Speaks: Original Work And Counter-Hegemonic Performance And Practice, Matthew Paul Thornton

Theses and Dissertations

Graduate study in theatre has allowed me to understand my work as an artist and educator from a critical academic perspective. I have researched Butoh as a model for original work that employs multiculturalism against hegemonic control of personal identity. From my own training experience, I am recognizing Capoeira, Contact Improvisation, and Devising processes (co-creation or collaborative creative process in dance) as counter-hegemonic forms and techniques that share a physical/philosophical emphasis on communal engagement, improvisation, circularity and repetition. Looking at them together provides points of intersection for me to examine them as an artist, while posing questions for cross-cultural investigations. …

Three Dimensional Homology Modeling Of Organic Cation Transporter 3 To Identify Structural Elements Mediating Transporter-Substrate Interactions, Hebing Liu

Theses and Dissertations

Organic cation transporters (OCTs) play a pivotal role in the absorption, tissue distribution, and excretion of a diverse array of substances, and currently the nature of the biochemical interactions between substrate and OCTs are unknown. Therefore, identifying which amino acid residues are critical for OCT-substrate interactions is of central importance to understanding and predicting interactions between drugs and OCTs. A three-dimensional (3-D) homology model of human OCT3 was generated using the crystal structure of a high affinity phosphate transporter from Piriformospora indica (PiPT) as template, and putative binding pocket for the prototypical hOCT3 ligand 1-methyl-4-phenylpyridinium (MPP⁺) was identified …

Design, Synthesis, And Biological Screening Of Selective Mu Opioid Receptor Ligands As Potential Treatments For Opioid Addiction, Samuel Obeng

Theses and Dissertations

Today, more Americans die each year because of drug overdoses than are killed in motor vehicle accidents. In fact, in 2015, more than 33,000 individuals died due to an overdose of heroin or prescription opioids. Sadly, 40-60 % of patients on current opioid addiction treatment medications relapse. Studies have shown that the addiction/abuse liability of opioids are abolished in mu opioid receptor (MOR) knock-out mice; this indicates that the addiction and abuse liability of opioids are mainly mediated through MOR. Utilizing the “message-address concept”, the our laboratory reported a novel non-peptide, reversible MOR selective ligand 17-cyclopropylmethyl-3,14β-dihydroxy-4,5α-epoxy-6α (isoquinoline-3-carboxamido)morphinan (NAQ). Molecular modeling …

Diabetes-Induced Expression And Regulation Of Glp-1 Levels By Bile Acid Receptors (Tgr5 & Fxr), Joseph R. Spengler

Theses and Dissertations

Diabetes Mellitus has continued to drastically affect the health of the world and many complications can prove fatal. As long as this metabolic disease persist, research discoveries will need to continue to be made so that patient outcomes and healthcare are dramatically enhanced. In recent years, GLP-1 has been the topic of conversation for diabetes research, due to its promising effects in promoting insulin sensitivity. Furthermore, bile acids and their receptors (TGR5 & FXR) have shown promise in their actions in the regulation of GLP-1, and thus glucose homeostasis. Here we have shown the detection and increased expression of TGR5 …

Walking In Beauty: Responsive And Responsible Health And Healing Among Virginia American Indian People, Amy J. Prorock-Ernest

Theses and Dissertations

Little is systematically known about the collective health and well-being of Virginia American Indian people. This study sought to explore the meaning of health and healing among Virginia American Indian people in the context of a reservation-based, non-federally funded health clinic. Using an emergent approach to qualitative research grounded in a constructivist inquiry paradigm and guided by Indigenous research principles, a total of 24 in-depth, semi-structured interviews were conducted with 17 American Indian service-users of the Clinic. Through an inductive thematic analysis of participant stories, a framework for understanding responsive and responsible health and healing was derived. The framework includes …

Alpha6 Beta2 Subunit Containing Nicotinic Acetylcholine Receptor Contributions To Abuse-Related Effects Of Nicotine And Alcohol, Alexandra M. Stafford

Theses and Dissertations

Pharmacotherapies for tobacco and alcohol cessation are only modestly successful, so it is important to better understand mechanisms underlying their use and abuse. The overarching goal of this research is to assess a6b2 subunit containing nicotinic acetylcholine receptor (a6b2*nAChR; *denotes possible assembly with other subunits) contributions to abuse-related effects of nicotine and alcohol. In the absence of a6b2*nAChR-selective agonists, a6b2*nAChR gain-of-function (a6L9’S) mice provide a tool for selective activation of a6b2*nAChRs. Using the a6L9’S mice together with nicotine doses sub-threshold for stimulation of native nAChRs, these studies tested the hypothesis that activation of a6b2*nAChRs is sufficient to promote neurochemical and …

Low-Temperature Fabrication Process For Integrated High-Aspect Ratio Metal Oxide Nanostructure Semiconductor Gas Sensors, William Paul Clavijo

Theses and Dissertations

This work presents a new low-temperature fabrication process of metal oxide nanostructures that allows high-aspect ratio zinc oxide (ZnO) and titanium dioxide (TiO₂) nanowires and nanotubes to be readily integrated with microelectronic devices for sensor applications. This process relies on a new method of forming a close-packed array of self-assembled high-aspect-ratio nanopores in an anodized aluminum oxide (AAO) template in a thin (2.5 µm) aluminum film deposited on a silicon and lithium niobate substrate (LiNbO₃). This technique is in sharp contrast to traditional free-standing thick film methods and the use of an integrated thin aluminum film …

Ethanol Reversal Of Oxycodone Tolerances, Joanna C. Jacob

Theses and Dissertations

Oxycodone is a semi-synthetic opioid originally developed as a safer alternative to morphine. It is commonly prescribed for its pain-relieving effects, but has recently been implicated as a major underlying cause of the current opioid epidemic due to its clinical limitations that include tolerance, dependence and a high abuse liability. Simultaneous consumption of opioids and ethanol has been shown to increase the risk of overdose and death from opioids in opioid-tolerant individuals. We hypothesized that ethanol reversed opioid tolerance and previous studies showed that ethanol reversed morphine tolerance. This dissertation investigated whether ethanol reversed tolerance to other opioids in mice, …

Community Gardens: Exploring Race, Racial Diversity And Social Capital In Urban Food Deserts, Jennifer F. Jettner

Theses and Dissertations

Study purpose. The study examined race and racial diversity in community gardens located in Southern urban food deserts, as well as the capacity of community gardens to generate social capital and promote social justice. Methods. A mixed-methods approach was used to describe characteristics of gardeners and community gardens located in urban food deserts, and test Social Capital Theory hypotheses. A convenience sample of 60 gardeners from 10 community gardens was obtained. Data was collected using surveys and semi-structured interviews. Analyses. Univariate and bivariate statistics were used to describe gardeners and gardens. Leader rationales for garden characteristics were analyzed using thematic …

Lung Disposition Model-Based Analyses Of Clinical Pharmacokinetic Profiles For Inhaled Drugs, Anuja Raut

Theses and Dissertations

There has been a desire to accurately interpret the inhaled pharmacokinetic (PK) profiles of drugs in humans to aid successful inhaled drug and product developments. However, challenges are layered, as 1) the drug dose delivered to the lung (DTL) from inhalers is a portion of the formulated dose but rarely determined; 2) lung delivery and regional deposition differ, depending on drug, formulation and inhaler; 3) drugs are not only absorbed from the lung but may also be from the gastrointestinal (GI) tract; and 4) in addition to absorption into the systemic circulation, multiple non-absorptive processes also eliminate drugs from the …

Interleukin-18 As A Therapeutic Target In Western-Diet Induced Cardiomyopathy, Pratyush Narayan

Theses and Dissertations

Background: Heart Failure (HF) is characterized by impaired cardiac function with symptoms of dyspnea, fatigue and exercise intolerance. Western diet (WD), a diet high in saturated fats and sugars, causes systemic increase in IL-18, a cytokine elevated in HF, which induces abnormal myocardial structure and diastolic dysfunction. IL-18 binding protein(IL-18BP) binds IL-18, preventing the binding to the IL-18-receptor. We investigated a therapeutic intervention using recombinant-murine IL-18BP to improve the WD-induced cardiomyopathy in C57BL/6J mice.

Methods: Echocardiography with pulse-wave Doppler and tissue imaging was performed to assess cardiac function. Oral glucose tolerance test was performed to assess metabolic parameters and IL-18 …

Gomds - Grumpy Old Men Doing Shakespeare; The Comedy Of Errors As Metaphor For Life, Aging, And Building Community, Elizabeth B. Pedersen

Theses and Dissertations

This thesis explores the process of building community over time, through collaboration, to rehearse and produce a portable production of Shakespeare's The Comedy of Errors, looking at the elements of time, trust and age with an ensemble of ten men, all actors over the age of 55. The building of trust over time was vital to the production process and the actors had the time to embody their roles and the language of the play. We look at the questions “why this play,” “why all men?” and “why theatre?” and investigate the physical nature of the play and its …

Short And Long Chain Free Fatty Acids Differentially Regulate Glucagon-Like Peptide-1 And Peptide Yy Transcript Levels In Enteroendocrine Cells (Stc-1), Colin M. Catherman

Theses and Dissertations

The regulation of glucagon-like peptide-1 and peptide YY hormone levels are regulated based on different influential factors, but primarily levels are dependent upon ingested food content. As meals today become more fat-enriched, there is greater requirement for evaluation of these hormones that regulate insulin and satiety levels within the body. We have shown that the gene expression transcript production of glucagon-like peptide-1 and peptide YY are modulated by different concentrations, and times of short-chain fatty acids and long-chain fatty acids. Although the peptide hormone levels have the influential physiological role on effector tissue, the regulation of these hormones begins at …

A Targeted Approach To Increasing The African American Blood Donor Pool, Arnethea L. Sutton

Theses and Dissertations

A continuous need for blood products, specifically for those who require frequent transfusions, such as individuals with sickle cell disease, warrants the need for targeted interventions to increase blood donations from underrepresented populations. One population in particular, African Americans, only account for 1% of blood donors in the United States. Literature indicates numerous reasons why this population is underrepresented amongst donors, including fear, lack of knowledge about the blood donation, and specific to this population, lack of trust in the medical community. This study involves the development, implementation, and assessment of a targeted educational approach, incorporating the Theory of Planned …

An Integrated Behavioral Model Of Healthcare Utilization Among Transgender And Gender-Nonconforming Adults, Megan Elizabeth Sutter

Theses and Dissertations

Transgender and gender-nonconforming (TGNC) individuals in the United States experience significant marginalization due to stigma enacted at the structural, interpersonal, and individual levels. As a result, this population has reported increased behavioral and physical health needs, as well as unique barriers to healthcare. Moreover, TGNC individuals have reported greater experiences of childhood abuse compared to cisgender individuals. The cumulative experiences of stigma-related stressors and adverse childhood experiences put this population at risk for the development of mental and physical health problems, increasing need for health services. However, TGNC individuals have reported being denied medical care and postponing seeking care due …

A Roadmap For Development Of Novel Antipsychotic Agents Based On A Risperidone Scaffold, Urjita H. Shah

Theses and Dissertations

Schizophrenia is a chronic psychotic illness affecting ~21 million people globally. Currently available antipsychotic agents act through a dopamine D₂ receptor mechanism, and produce extrapyramidal or metabolic side effects. Hence, there is a need for novel targets and agents. The mGlu₂/5-HT_2A receptor heteromer has been implicated in the action of antipsychotic agents, and represents a novel and attractive therapeutic target for the treatment of schizophrenia. A long-term goal of this project is to synthesize bivalent ligands where a 5-HT_2A receptor antagonist is tethered to an mGlu₂ PAM via a linker.

The goals of the …

Socioecological Aspects Of Tobacco Use In College Populations, Michael D. Sawdey

Theses and Dissertations

Background: Although cigarette smoking is decreasing in the US and among college students, tobacco use remains a major public health problem. Specific socioecological gaps in the literature related to college tobacco use exist including: trends of tobacco use, combinations of polysubstance use, and availability of tobacco products around college campuses.

Objectives: The main goal of this research was the understand interrelationships that exist within a socioecological framework of college tobacco use. Specifically, this project aims to: 1) examine trends of tobacco and polytobacco use by gender and associations of polytobacco use and perceived peer tobacco use, 2) examine …

Art For Recovery, Lucy Dabney

Theses and Dissertations

This thesis explores the design of a space for opioid addicts in recovery that combines an art therapy studio with a gallery space. It would provide a new type of therapy available to the area, engage and educate the Richmond community and spread awareness of the disease of opiate addiction. It will also enable addicts to express themselves in a non-verbal, creative format that allows for them to create a legacy and leave an imprint on the community.

Electronic And Structural Study Of The Reactivity Of Cu+ With Co, H2o, O2, N2 And Their Mixture, Cara M. Frame

Theses and Dissertations

A detailed theoretical study of the gas phase reactivity of copper cation (Cu⁺) with CO, H₂O, O₂, N₂ and their mixture was performed and compared to experimental results to determine the ability of Cu⁺ to act as a low-temperature catalyst for CO oxidation. It was found that Cu⁺ binds strongest to CO, followed by H₂O, N₂, and O₂, strongly interacting with each species until reaching saturation at a maximum of four ligands. It was also found that a single Cu …

The Dual Faces Of Misery, Arden Moscati

Theses and Dissertations

Major Depression (MD) and Generalized Anxiety Disorder (GAD) are psychiatric disorders that arise from dysfunction of the core human capacities for emotion. Sapience is inextricably bound up with the potential for feelings of regret, worry and concern. When these emotions lead to clinically significant impairment or distress, they may result in one or both of the disorders of MD and GAD. The occurrence of MD and GAD in the same person, known as comorbidity, is remarkably high; substantially higher than would be expected by chance.

MD and GAD have been studied since the mid-20^th century, resulting in a substantial …

Altering A Runner’S Foot Strike Using A Modified Elliptical Trainer, Daniel Shull

Theses and Dissertations

One possible solution to common running related injuries is to transition runners from a rearfoot strike during initial contact to a midfoot strike. Natural rearfoot strike runners were studied to see if a modified elliptical trainer could be used to alter their running pattern to that of a midfoot strike runner. Their results were compared to subjects who ran on a non-modified elliptical trainer. After training on the modified elliptical trainer, subjects demonstrated a decrease in foot angle at initial contact when attempting to run with a midfoot strike. Training did not affect all kinetic metrics or stride frequency. However, …