Digital Commons Network^™

Exploring Stakeholders' Perceptions Of The Evaluation Of Early Fieldwork Experience In An Undergraduate Teacher Preparation Program, Amber R. Peacock

Theses and Dissertations

This study is a qualitative meta-evaluation of the early field experience (EFE) program at a small, private, undergraduate teacher preparation program in Virginia focusing on the perceptions of preservice teachers, cooperating teachers and course instructors about the EFE evaluation objectives, evaluation experience, and resulting data usage. The EFE evaluation protocol at the study site is explored using a participatory-oriented evaluation model that solicited the perceptions of stakeholders. Analysis of EFE evaluation documents and semi-structured interviews with the stakeholders were conducted to explore the extent to which (1) official EFE objectives are congruent with the EFE evaluation, (2) the intended evaluation …

The Characterization Of A Putative Virulence Factor Expressed By Sneathia Amnii, Amy Sanford

Theses and Dissertations

Preterm birth, defined at birth before 37 weeks gestation, affects millions of newborns worldwide every year. Preterm birth is a leading cause of infant morbidity and mortality. One major cause of preterm birth is preterm premature rupture of membranes (PPROM), which can be triggered by bacterial infection and inflammation. A bacterial species that has been implicated in preterm birth and other obstetric complications is Sneathia amnii. The goals of this study were to observe cytopathogenic effects caused by S. amnii strain Sn35 and identify putative virulence factors causing those effects. Sn35 was able to adhere to, invade, and damage/kill …

Expression And Pharmacological Modulation Of Pain-Depressed Behavior In Rats, Michael D. Leitl

Theses and Dissertations

Pain is often associated with depression of behavior and mood, and relief of pain-related depression is a common goal of treatment. This goal of this dissertation was to conduct preclinical research experiments designed to address a set of three inter-related aims that examine the expression, mechanisms and treatment of pain-related depression of Intracranial Self-Stimulation (ICSS) in rats. First, studies evaluated the hypothesis that acute acid-induced depression of ICSS was mediated by a kappa opioid receptor mediated decrease in mesolimbic dopamine release in the nucleus accumbens. Results support a role for depressed mesolimbic dopamine release in pain-related depression of ICSS; however, …

Depletion Of The Chromatin Remodeler Chd4 Sensitizes Aml Blasts To Genotoxic Agents And Reduces Tumor Formation, Justin Sperlazza

Theses and Dissertations

Chromodomain Helicase DNA-Binding Protein 4 (CHD4) is an ATPase that alters the phasing of nucleosomes on DNA and has recently been implicated in DNA double stranded break (DSB) repair. Here, we show that depletion of CHD4 in Acute Myeloid Leukemia (AML) blasts induces a global relaxation of chromatin that renders cells more susceptible to DSB formation, while concurrently impeding their repair. Furthermore, CHD4 depletion renders AML blasts more sensitive both in vitro and in vivo to genotoxic agents used in clinical therapy: daunorubicin (DNR) and cytarabine (ara-C). Sensitization to DNR and ara-C is mediated in part by activation of the …

Pemetrexed, A Modulator Of Amp-Activated Kinase Signaling And An Inhibitor Of Wild Type And Mutant P53, Stuti Agarwal

Theses and Dissertations

New drug discoveries and new approaches towards diagnosis and treatment have improved cancer therapeutics remarkably. One of the most influential and effective discoveries in the field of cancer therapeutics was antimetabolites, such as the antifolates. The interest in antifolates increased as some of the antifolates showed responses in cancers, such as mesothelioma, leukemia, and breast cancers. When pemetrexed (PTX) was discovered, our laboratory had established that the primary mechanism of action of pemetrexed is to inhibit thymidylate 22 synthase (TS) (E. Taylor et al., 1992). Preclinical studies have shown that PTX has a broad range of antitumor activity in human …

Investigating The Role Of The Nucleosome Remodeling Factor Nurf As A Regulator Of Gene Expression, Aiman S. Alhazmi

Theses and Dissertations

The nucleosome remodeling factor (NURF) is an evolutionary conserved ATP-dependent chromatin remodeling factor. It was first isolated from Drosophila as a complex with enzymatic activity that once recruited to nucleosome, it slides the nucleosome to provide accessibility for transcription factors. Since then, numerous works from animal models and cell lines show the role of NURF as a regulator of gene expression. NURF interacts with H3K4me3 and sequence specific transcription factors that recruit the complex to promoter regions. Whether this is the only mechanism by which NURF regulates gene expression is not known. However, other ATP-dependent chromatin remodeling complexes are known …

A Novel Antimicrobial Drug Discovery Approach For The Periodontal Pathogen Porphyromonas Gingivalis, Victoria N. Stone

Theses and Dissertations

The human body is colonized by more than 100 trillion microbes which make up an essential part of the body and plays a significant role in health. We now know the over use and misuse of broad-spectrum antibiotics can disrupt this microbiome contributing to the onset of disease and runs the risk of promoting antibiotic resistance. With antibiotic research still on the decline, new strategies are greatly needed to combat emerging pathogens while maintaining a healthy microbiome. We therefore set out to present a novel species-selective antimicrobial drug discovery strategy.

Disruption of the homeostasis within the oral cavity can trigger …

Variations In Specialized Policing Response Models As A Function Of Community Characteristics- A Survey Of Crisis Intervention Team Coordinators, Anna M. Young

Theses and Dissertations

Although a specific program called the Crisis Intervention Team (CIT) has been generally recognized as the best-practice model that addresses the needs of the police officers in responding to mental health calls, many jurisdictions across the country have not only adopted the full CIT model but also have taken the liberty of adding new components and/or removing components of the original model in order to create a unique program that fits the needs of their individual community. The issue of differentiated adaptations of the original CIT model has created a controversy around best practice in the area of police response …

First-Generation College Students: A Qualitative Exploration Of The Relationship Between Parental Education Level And Perceptions Of Faculty-Student Interaction, Micol Hutchison

Theses and Dissertations

While quantitative research has determined that first-generation college students (FGS) are less likely to interact with faculty than are their non-FGS peers, this qualitative study examines how incoming first-year college students, both FGS and non-FGS, perceive faculty-student interaction and whether they consider it important. Addressing different types of interaction with college instructors, both in-class and out-of-class, participants across a range of FGS status shared their views through surveys, individual interviews, and focus groups. Focusing specifically on incoming first year students, this study also explores the motives for, impediments to, and encouragements to faculty-student interaction that students identify. Finally, the study …

The Architecture Of Knowledge: The Jesuit College Of Oaxaca (Xvi-Xix Centuries)., Marina Mellado Corriente

Theses and Dissertations

ABSTRACT

THE ARCHITECTURE OF KNOWLEDGE: THE JESUIT COLLEGE OF OAXACA (XVI-XIX CENTURIES).

By Marina Mellado Corriente, MA.

A dissertation submitted in partial fulfillment of the requirements for the degree of Doctor of Philosophy in Art Historical and Curatorial Studies at Virginia Commonwealth University.

Virginia Commonwealth University, 2015

Major Director: Michael Schreffler, Associate Professor, Department of Art History

The educational endeavor that the Jesuits – members of the religious order known as the Society of Jesus – carried out in Mexico in the course of the colonial period, when this territory belonged to the Viceroyalty of New Spain (sixteenth to nineteenth …

Effects Of Hiv-1 Viral Protein Tat On The Viability And Function Of Oligodendroglial Cells, Shiping Zou

Theses and Dissertations

Myelin pallor is frequently reported in HIV patients, and can occur in the CNS prior to other evidence of disease process. Our exploratory studies showed that oligodendrocytes (OLs) are direct targets of HIV-1 Tat (transactivator of transcription). Tat induces a dose-dependent increase of intracellular Ca²⁺ level ([Ca²⁺]_i) in cultured murine OLs, which can be attenuated by ionotropic glutamate receptor (iGluR) antagonists MK801 and CNQX. The Tat-induced [Ca²⁺]_i increase leads to increased death in immature (O4⁺, MBP^-), but not mature (O4⁺, MBP⁺) OLs, over 96 …

A Case Study Examining Formative Assessment In A Postsecondary English Language Program, Divya Varier

Theses and Dissertations

This study examined the formative assessment practices of three teachers in English as a Second Language (ESL) classrooms using a sociocultural theoretical framework. The study was conducted in a postsecondary ESL setting at a large public university in the southeastern United States. Using an embedded mixed methods design, this study employed teacher interviews and classroom observations to address the overarching question: What individual and contextual factors are present in the formative assessment practices of participant ESL teachers? The study also explored the relationship between student metacognitive judgments of learning (JOL) and performance with the purpose of informing formative assessment practice. …

Consequences Of Vine Infestation: Linking Abiotic Influences And Biotic Interactions To Successional And Structural Changes In Coastal Communities, Spencer N. Bissett

Theses and Dissertations

Located at the interfaces of terrestrial and marine environments, coastal habitats are inherently vulnerable to the effects of global change. Barrier island systems in particular serve not only as protective buffers against storm events, but also as sentinel ecosystems for observation of the impacts of sea level rise, and of increasing storm frequency and intensity. In the mid-Atlantic region, shrub thickets of Morella species compose the dominant forest community. The often monospecific nature of these plant community assemblages is advantageous to ecological studies and cross-scale applications; the relatively low diversity facilitates transitions between scales. My objective was to investigate the …

Computational Modeling To Assess Surgical Procedures For The Treatment Of Adult Acquired Flatfoot Deformity, Brian A. Smith

Theses and Dissertations

Several surgically corrective procedures are considered to treat Adult Acquired Flatfoot Deformity (AAFD) patients, relieve pain, and restore function. Procedure selection is based on best practices and surgeon preference. Recent research created patient specific models of Adult Acquired Flatfoot Deformity (AAFD) to explore their predictive capabilities and examine effectiveness of the surgical procedure used to treat the deformity. The models’ behavior was governed solely by patient bodyweight, soft tissue constraints, and joint contact without the assumption of idealized joints. The current work expanded those models to determine if an alternate procedure would be more effective for the individual. These procedures …

Effects Of Constant Vs. Fluctuating Temperatures On Performance And Life History Of The Herbivorous Pest Lymantria Dispar (Lepidoptera: Eribidae), Brendan E. Sostak

Theses and Dissertations

The role of temperature variation in organismal performance is understudied, but is critically important for understanding the response of biodiversity to climate change. To address this issue in herbivorous insects, I studied the direct and interactive effects of thermal regime (constant vs. fluctuating temperatures) and nutrition (dietary nitrogen) on gypsy moth (Lymantria dispar) performance under laboratory conditions. Predictions for differences between constant and fluctuating thermal conditions were derived from Jensen’s inequality, and artificial diets of differing nutritional quality were made by modifying nitrogen (casein) content. Larvae were reared in the laboratory under four temperature regimes (22°C constant, 22°C …

Orientia Tsutsugamushi Ankyrin-Repeat Protein Family Targeting Of The Host Endoplasmic Reticulum, Lauren Viebrock

Theses and Dissertations

Abstract

ORIENTIA TSUTSUGAMUSHI ANKYRIN REPEAT-PROTEIN FAMILY TARGETING OF THE HOST ENDOPLASMIC RETICULUM

By Lauren VieBrock, B.S.

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

Virginia Commonwealth University, 2015

Director: Jason A. Carlyon, Ph.D.

Professor

Microbiology and Immunology

Scrub typhus is an understudied, potentially fatal febrile illness, which poses threat to one billion people annually in the Asia-Pacific region. The host-pathogen interactions that facilitate the intracellular survival of the etiologic agent, Orientia tsutsugamushi, are not well understood. The Orientia tsutsugamushi genome encodes a large number of ankyrin repeat-containing proteins …

Discrete Nonlinear Planar Systems And Applications To Biological Population Models, Shushan Lazaryan, Nika Lazaryan, Nika Lazaryan

Theses and Dissertations

We study planar systems of difference equations and applications to biological models of species populations. Central to the analysis of this study is the idea of folding - the method of transforming systems of difference equations into higher order scalar difference equations. Two classes of second order equations are studied: quadratic fractional and exponential.

We investigate the boundedness and persistence of solutions, the global stability of the positive fixed point and the occurrence of periodic solutions of the quadratic rational equations. These results are applied to a class of linear/rational systems that can be transformed into a quadratic fractional equation …

Avatar, Cyborg, Icevorg: Simulacra’S Scion, Guido E. Alvarez

Theses and Dissertations

I propose a theoretical framework that describes how avatars incorporate media as an inherent part of their nature and find a hosting body in cyborgs to navigate and spawn in media. I propose the birth of a new scion that combines avatar, medium and cyborg into a conceptual being that I call “ICEVORG.”

The ICEVORG expands beyond representation into the actual physical world by means of media transgression—more specifically, by the use of the Strange Loop also known as Metalepsis ICEVORG find an effective soil to thrive and interrogate our ideas of reality by means of iteration, expansion, fragmentation and …

Expanding Eco-Visualization: Sculpting Corn Production, Jennifer E. Figg

Theses and Dissertations

This dissertation expands upon the definition of eco-visualization artwork. EV was originally defined in 2006 by Tiffany Holmes as a way to display the real time consumption statistics of key environmental resources for the goal of promoting ecological literacy. I assert that the final forms of EV artworks are not necessarily dependent on technology, and can differ in terms of media used, in that they can be sculptural, video-based, or static two-dimensional forms that communicate interpreted environmental information. There are two main categories of EV: one that is predominantly screen-based and another that employs a variety of modes of representation …

Edgar Allan Poe And Science: Unraveling The Plot Of The Universe, Murray S. Ellison

Theses and Dissertations

Edgar Allan Poe (1809-49) lived at the perfect time to write about several of the most dramatic technological developments ever recorded in history. Up until the nineteenth century, professional scientists were almost the exclusive agents for writing about science. However, during this period, non-professional writers also emerged as important conveyors of popular science news to the public. Though Poe was a lay writer, his popular writing conveyed several of the most important new discoveries of the Industrial Age. He also projected his views about how nineteenth-century technologies might impact civilizations of the future. Poe’s writing offers a key example of …

K-12 Educational Programs In Contemporary Art Museums: An Examination Of University And Non-University Non-Collecting Institutions Of Contemporary Art, Susan Moser

Theses and Dissertations

This museum thesis project will provide an overview of kindergarten through 12^th-grade (K-12) educational programs at six non-collecting art institutions within the United States, contextualized within a selected historiography of art museum education. This project is designed to aid the Virginia Commonwealth University Institute for Contemporary Art (ICA). The ICA is a non-collecting institution that will be located on VCU’s Monroe Park campus. As the ICA staff sets out to articulate a vision and scope for its K-12 education programs, it will benefit from the information offered in this thesis project, especially given that there is no existing …

Clinical And Genomic Characterization Of Two Vaginal Megasphaera Species, Abigail L. Glascock

Theses and Dissertations

Two vaginal phylotypes of the genus Megasphaera (phylotype 1 and phylotype 2) were recently associated with bacterial vaginosis (BV), an infection characterized by vaginal dysbiosis. Through an analysis of 16S rRNA profiles of 3,986 women enrolled in the Vaginal Human Microbiome Project, we confirmed that while both phylotypes were associated with BV, Megaspheara phylotype 1 had higher specificity for the condition. Megasphaera phylotype 2 was strongly associated with trichomoniasis. Previous studies have reported that BV-associated organisms are excluded in pregnancy. We observed that Megasphaera phylotype 1, which has been associated with adverse pregnancy outcomes, exhibited a trend of increased prevalence …

The Role Of Α3Β4* Subtype Of Nicotinic Acetylcholine Receptors In Reversing Opioid-Induced Constipation In Mice, Aravind Gade

Theses and Dissertations

Opioids are excellent pain relievers. A major side-effect of chronic opioid treatment is constipation whereas withdrawal following chronic exposure leads to diarrhea and increased gastrointestinal motility. These effects of chronic opioids are mediated by μ-opioid receptors expressed on enteric neurons. Previous studies have shown that chronic opioids enhance sensitivity to nicotine in the gastrointestinal tract. This suggested that prokinetic effects of nicotine mediated through the activation of nicotinic acetylcholine receptors (nAChRs) may be useful in reversing opioid-induced constipation. The goal of this dissertation was to investigate the nAChR subtype expressed on enteric neurons and their role in reversing opioid-induced constipation. …

Meta-Analysis Of Gene Expression Studies, Umaporn Siangphoe

Theses and Dissertations

Combining effect sizes from individual studies using random-effects models are commonly applied in high-dimensional gene expression data. However, unknown study heterogeneity can arise from inconsistency of sample qualities and experimental conditions. High heterogeneity of effect sizes can reduce statistical power of the models. We proposed two new methods for random effects estimation and measurements for model variation and strength of the study heterogeneity. We then developed a statistical technique to test for significance of random effects and identify heterogeneous genes. We also proposed another meta-analytic approach that incorporates informative weights in the random effects meta-analysis models. We compared the proposed …

Using Structural Equation Modeling To Understand The Role Of The Family In Pediatric Asthma Contexts, Nour Al Ghriwati

Theses and Dissertations

Family factors have long been associated with the psychosocial adjustment of children with chronic illnesses, such as asthma (Minuchin, 1975; Rapee, 1997). Research indicates that negative family factors may also contribute to child disease severity, via bio-behavioral mechanisms of effect (Wood et al., 2006); however, these pathways have yet to be examined with a comprehensive focus on more positive family factors. This study sought to examine whether factors such as family cohesion, problem solving abilities, and communication influence asthma symptom severity in children via their effects on child depression and anxiety symptoms. Using structural equation modeling, we identified significant indirect …

Psychoactive Synthetic Cathinones (Or 'Bath Salts'): Investigation Of Mechanisms Of Action, Farhana Sakloth

Theses and Dissertations

Synthetic cathinones represent threatening and high abuse-potential designer drugs. These are analogs of cathinone (the b-keto analog of amphetamine (AMPH)) a naturally occurring stimulant found in the plant Catha Edulis. Methcathinone (MCAT) was the first synthetic analog of cathinone to be identified in 1987 by Glennon and co-workers and it exerted its action primarily through the dopamine transporter (DAT). Most central stimulants exert their action via monomaine transporters by causing either the release (e.g. cathinone analogs such as MCAT) or by preventing the reuptake (e.g. cocaine) of the neurotransmitter dopamine (DA) thus increasing the extracellular synaptosomal concentration of this …

First-Year Secondary Teachers’ Perceptions Of Their Preparedness To Integrate 21st Century Skills Into The Technology-Rich Classroom, Tracie Omohundro

Theses and Dissertations

School districts continue to integrate emerging technologies and expectations for 21^st century teaching and learning. This movement began with release of Goals 2000 (1994) and has continued through National Education Technology Plan (2010) that noted the “challenge for our education system is to leverage technology to create relevant learning experiences that mirror students’ daily lives and the reality of their futures.” In order to meet that challenge, schools must enlist teachers who are prepared to teach 21^st century skills in the technology-rich classroom. Teacher education programs also need to align their preparation models to prepare teachers for that …

Λcdm Cosmology + Chaotic Inflation, Peter A. Farago

Theses and Dissertations

ΛCDM cosmology is described in terms of general relativity and the Robertson-Walker metric. The evolution of the observable universe, currently dominated by dark energy (Λ) and cold dark matter (CDM), is presented in terms of its thermal history. CDM is extended to include an inflation epoch that accelerates the early expansion rate to near exponential levels. It is shown that inflation solves several problems in CDM and produces perturbations in the metric that lead to the observed anisotropies in the Cosmic Microwave Background and the formation of large scale cosmological structures. Various theories of inflation are explored. Predictions of inflation …

Interaction Between Atm Kinase And P53 In Determining Glioma Radiosensitivity, Syed F. Ahmad

Theses and Dissertations

Glioblastoma multiforme (GBM) is the most common primary brain tumor. Studies have shown that targeting the DNA damage response can sensitize cancer cells to DNA damaging agents. Ataxia telangiectasia mutated (ATM) is involved in signaling DNA double strand breaks. Our group has previously shown that ATM inhibitors (ATMi) sensitize GBM cells and tumors to ionizing radiation. This effect is greater when the tumor suppressor p53 is mutated.

The goals of this work include validation of a new ATM inhibitor, AZ32, and elucidation of how ATMi and p53 status interact to promote cell death after radiation. We propose that ATMi and …

Factors That Influence Breast Cancer Diagnoses In Virginia Women 40-64 Years Old Who Utlized The Every Woman’S Life Program 1998-2012, Melanie C. Dempsey

Theses and Dissertations

This dissertation examines sociodemographic determinants and preventive health behaviors among women 40-64 years of age who participated in the Virginia Department of Health’s Every Woman’s Life breast cancer screening program. Utilizing secondary data, this research sought to explore patterns of breast cancer incidence, mammography screening utilization and sources of health information among low-income women.

The Virginia Department of Health provided a large sample size (N=34,942) on which to perform binary logistic regression analyses. Sociodemographic determinants and preventive health behaviors were analyzed as potential influencing factors in the diagnosis of breast cancer, the stage at the time of diagnosis and source …