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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 …

The Role Of The Nucleosome Remodeling Factor Nurf In Inhibiting T And Natural Killer Cell Mediated Antitumor Immunity By Suppressing Tumor Antigenicity And Natural Cytotoxicity Receptor Co-Ligands, Kimberly Mayes

Theses and Dissertations

Tumor immunoediting is a dynamic process in which the immune response attacks tumor cells by detecting danger signals and tumor antigens. In order to survive, tumor cells develop mechanisms to avoid detection or destruction by the immune system. To counteract this, several strategies are being developed to enhance the antitumor immune response, including the depletion of immunosuppressive cells, enhancing the activation of antitumor immune cells and increasing tumor cell immunogenicity. These therapies have seen limited success individually, however, and it is likely that combination therapy with novel targets will be necessary to see reproducible beneficial responses. Epigenetic modifications are attractive …

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 …

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 …

Functional Study Of Cmya5, A Candidate Gene For Schizophrenia, Anting Hsiung

Theses and Dissertations

CMYA5 is a candidate gene for schizophrenia because of the association of variant rs10043986 (Pro4063Leu). Studies of CMYA5 and its gene product, myospryn, in brain and neuronal cells have not been previously reported. We examined the neuronal expression of myospryn and its binding partner, desmin intermediate filament (IF), and investigated the difference in binding and colocalization of the two alleles of myospryn to IFs. Myospryn and desmin are expressed in brain regions. Using yeast two-hybrid and surface plasmon resonance, the T allele (Leu) is found to have higher binding affinity to desmin than the C allele (Pro). Myospryn localizes to …

Application Of The Fisher Dimer Model To Dna Condensation, John C. Baker Iii

Theses and Dissertations

This paper considers the statistical mechanics occupation of the edge of a single helix of DNA by simple polymers. Using Fisher's exact closed form solution for dimers on a two-dimensional lattice, a one-dimensional lattice is created mathematically that is occupied by dimers, monomers, and holes. The free energy, entropy, average occupation, and total charge on the lattice are found through the usual statistical methods. The results demonstrate the charge inversion required for a DNA helix to undergo DNA condensation.

Effects Of Hydraulic Dredging And Vessel Operation On Atlantic Sturgeon Behavior In A Large Coastal River, Michael R. Barber

Theses and Dissertations

The tidal James River, a focus of VCU's Atlantic Sturgeon program, supports both commercial shipping and hydraulic dredging. These anthropogenic threats present documented but preventable sources of mortality to the endangered species. Using three separate VEMCO Positioning System (VPS) receiver arrays, spatial data of previously-tagged fish were collected. ArcGIS and Programita software were used to analyze fish spatial distributions in the presence and absence of potential threats, using additional data including automatic identification system (AIS) vessel locations, vessel passages compiled using camera footage, and dredge records provided by the US Army Corps of Engineers. The data showed a change in …

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 …

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 …

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 …

Zebrafish (Danio Rerio) As A Model For Orofacial Research, Kevin A. Ghaffari

Theses and Dissertations

Across species, the face and more specifically the mouth, serves as an essential facet of everyday life. Amongst humans the mouth serves as a tool for the ingestion of food, a marker for facial recognition and a medium for communication. In order for the mouth to properly form, a series of precise growth and fusion events are needed. In order to insure that these events are orchestrated properly is a wide array of signals, transcription factors and epigenetic regulators. Due to the needed precision of these events, congenital birth defects of the face such as cleft lip and cleft palate …

The Monstrous Self: Negotiating The Boundary Of The Abject, Katya Yakubov

Theses and Dissertations

Through the lens of the horror film and the fairy tale, this thesis explores the notion of the grotesque as a boundary phenomenon—a negotiation of what is self and what is other. As such, it locates the function that the monstrous and the grotesque have in the formation of a personal and social identity. In asking why we take pleasure in the perverse, I explore how permutations of guilt, victimhood, and desire can be actively rewritten, in order to construct a stable sense of self.

Construction Of An Album For Oneself, Maria Tinaut

Theses and Dissertations

My work focuses on the construction and validation of images assembled from fragments of found photographs, generating new narratives that hover between “reality” and fiction. Archive and Fiction: Construction of the past and the self is the result of two years of artwork exploring my family archives and my relationship to my family through them. I understand the family as a place of identity in continuous change, serving as a container of history and memory. Conceiving of my family albums as material allows me to approach my family history as a visitor. Mediated memory and constructed memory intertwine in the …

Adventures Close To Home, Ryan Syrell

Theses and Dissertations

My work articulates experiences of intimacy and porosity with regard to domestic space. I think of these paintings as fields of interrelatedness which work to dismantle the perceived thresholds between things. The following text brings together the research of my studio practice and a survey of artists, writers, and filmmakers who have charted related spaces of the ordinary, domestic, and porous.

Nature Nurtures, Moriah Rhodes

Theses and Dissertations

Richmond, Virginia is defined by our connection to the James River. The James River Park system stretches over 550 acres of natural beauty. The park is broken into 14 different sections from the Huguenot Bridge in the west to a half mile beyond the I-95 Bridge in the east. The James River includes water features that appeal to the young and curious to the most experienced river-adventurer. The James River Park System boasts idyllic shorelines, peaceful meadows, and miles of challenging hiking and biking trails that appeal to the community and guests alike. Every year thousands of people come to …

Biochemical Analysis Of Putative Single-Stranded Nucleic Acid Binding Proteins In Porphyromonas Gingivalis, Steve H. Kokorelis

Theses and Dissertations

Proteins that bind to both DNA and RNA embody the ability to perform multiple functions by a single gene product. These nucleic acid binding proteins in prokaryotes can play a vital role in many cellular processes, including replication, transcription, gene expression, recombination, and repair, to name a few. Nucleic acid binding proteins have unique functional characteristics that stem from their structural attributes that have evolved in a widely-conserved manner. In Escherichia coli (E. coli), the highly-conserved histone-like protein, HU, which predominates as a heterodimer of HUα and HUβ, has been found to bind to both dsDNA and ssDNA. …

Nanocomposite Bioelectronics For Biopotential Enabled Prosthesis, Dong Sup Lee

Theses and Dissertations

Soft material-enabled electronics can demonstrate extreme mechanical flexibility and stretchability. Such compliant, comfortable electronics allow continuous, long-term measurement of biopotentials on the skin. Manufacturing of the stretchable electronic devices is enabled by the recent development combining materials transfer printing and microfabrication. However, the existing method using inorganic materials and multi-layered polymers requires long material preparation time and expensive processing cost due to the requirement of microfabrication tools and complicated transfer printing steps. Here, this study develops a new fabrication method of soft electronics via a micro-replica-molding technique, which allows fast production, multiple use, and low cost by avoiding microfabrication and …

The Role Of Mindfulness In The Regulation Of Behavior Among Those Prone To Negative Urgency, Alexandra M. Martelli

Theses and Dissertations

Negative emotions can be challenging to regulate, and for some individuals can lead to failures of behavior regulation. The present study is an initial effort to explore the role that mindfulness may play in fostering effective behavior regulation among those prone to high negative urgency (NU). Eighty undergraduate students were recruited based on their high or low scores of NU. First, participants completed a self-report measure of mindfulness (Mindful Attention Awareness Scale; MAAS), an Emotional Go/No Go task in an fMRI scanner, and then reported alcohol consumption. Results showed that those with high in NU had low levels of mindfulness …

Characterizing The Role Of Key Planar Cell Polarity Pathway Components In Axon Guidance, Grayland W. Godfrey Ii

Theses and Dissertations

An essential process to the development of the neural network of the nervous system is axon guidance. The noncanonical Wnt/Planar Cell Polarity pathway has been identified as an integral component in controlling the projection of axons during axon guidance. Prickle, ROR1 and ROR2 are PCP related proteins that do not have clearly defined roles in the process. This study aims to use zebrafish CoPA neurons as a model to study the roles of Prickle, ROR1, and ROR2 in axon guidance. Using in situ hybridization, morpholino knockdown, and CRISPR/Cas9 loss of function experiments were able to identify ror1, ror2 and …

Quantitative Analysis And Process Of High Speed Live Cell Interferometry Measurements, Daniel Guest

Theses and Dissertations

The application of auto focus, using an optical beam deflection technique, to existing live cell interferometry measurements was developed and examined. The benefit to relevant experiments, currently being performed, is shown as well as its performance across various magnifications. Enough information is given so that the system can be reproduced to fit any end users needs.

Niche Conservatism Or Divergence: Insights Into The Evolutionary Histories Of Pinus Taeda, Pinus Rigida, And Pinus Pungens, Constance E. Bolte

Theses and Dissertations

Environmentally related selective pressures and community interactions are well-documented drivers for niche differentiation, as natural selection acts on adaptive traits best fit for survival. Here, we investigated niche evolution between and within Pinus taeda, Pinus rigida, and Pinus pungens and sought to identify which climate variables contributed to species divergence. We also sought to describe niche differentiation across genetic groupings previously identified for P. taeda and P. rigida. Ecological niche models were produced using Maximum Entropy followed by statistical testing based on a measure of niche overlap, Schoener’s D. Both niche conservatism and niche divergence were …

Effect Of Charged Species On The Gradient Properties, Kayesh Ashraf

Theses and Dissertations

Surface chemical gradients are materials that exhibit continuous, gradually varying chemical or physical properties along and across the length of a substrate. As a result, each point on the gradient surface can represent an individual sample. They are broadly classified as chemical and physical gradients depending upon the properties that the gradient exhibits. A physical gradient involves a continuous variation of physical properties such as surface roughness and film porosity on the micrometer scale. Chemical gradients involve a gradual variation of chemical properties such as polarity, acidity and basicity, etc. Such gradients have found various applications in cell adhesion, nanoparticle …

Combining Noxa-Inducing Drugs With Abt-263 To Efficiently Increase Cell Death In Head And Neck Squamous Cell Carcinoma (Hnscc), Sung Woo Kim

Theses and Dissertations

Head and neck cancer is the sixth leading cancer worldwide. Head and neck squamous cell carcinoma (HNSCC) accounts for more than 90% of incident cases. Despite intense, multimodality treatment regimens for HNSCC including surgery, chemotherapy, and radiation, little progress has been made over the past 30 years in improving overall survival rates. Tumor cell death induced by both conventional and targeted chemotherapy is often mediated by the BCL-2 family-dependent mitochondrial apoptotic pathway. However, initiators of this apoptotic pathway, such as p53, are more than 50% of the time mutated or deleted in HNSCC rendering the disease refractory to treatment. To …

Hydrogen Peroxide And Pharmacological Agent Modulation Of Trpv2 Channel Gating, Tuoxin Cao

Theses and Dissertations

Transient receptor potential vanilloid 2 channel (TRPV2) is a Ca²⁺-permeable ion channel that is highly expressed in leukocytes but is also present in skeletal and cardiac muscle and endocrine cells. The TRPV2 function is implicated in a number of physiological processes, including bacterial phagocytosis, pro-inflammatory cytokine production, cardiac hypertrophy, and cancer development. TRPV2 knockout mice exhibit a high incidence of perinatal mortality, arguing that the channel plays essential roles in physiology. Despite the importance of TRPV2 for normal homeostasis, the mechanisms that control TRPV2 gating in response to pharmacological agonists, heating, membrane stretch, bioactive lipids and reactive oxygen …

Sustainable Adapted Treatments For Eating Disorders: The Role Of Cultural Adaptation In Prevention, Sarah J. Javier

Theses and Dissertations

Despite demonstrating eating disorder rates equivalent to White women, African American and Asian American women are less likely to seek treatment and are more likely to terminate treatment prematurely. One of the most successful programs for eating disorder prevention has only focused on surface-level cultural adaptations. Prevention literature maintains that deep-structure cultural adaptation (e.g., integrating cultural values and beliefs) can enhance outcomes for ethnic minorities. This dissertation examined the feasibility of Sustainable Adapted Treatments for Eating Disorders (SATED), a pilot intervention that included a culturally- targeted pre-treatment to an eating disorder dissonance-based intervention. A sample of 72 women (ages 18-30) …