Digital Commons Network^™

The Effect Of Chronic Nutrient Addition From Wastewater On Forest Ecosystems At The Rice Rivers Center, Michael Beck

Theses and Dissertations

Wastewater application to land can be a useful tool for mitigating impacts of nutrient enrichment on aquatic systems. A land application treatment system at VCU’s Rice Rivers Center in Charles City County, VA provided an opportunity to study the impact of wastewater addition on the biogeochemistry of forests representative of the Mid-Atlantic Coastal Plain. Nutrient concentrations in throughfall and leachate were measured at Treatment and Control sites to assess differences in nutrient deposition and retention. Wastewater amended plots from the Walter L. Rice education building received 20-fold (N) and 6-fold (P) higher inputs relative to Control plots and plots located …

Electrospraying Extracellular Matrix To Form Nanoparticles, Patrick Link

Theses and Dissertations

Chronic Obstructive Pulmonary Disease (COPD) is a leading cause of death worldwide. Alveolar wall destruction is a significant contributor to COPD. Inflammatory macrophages are a major source of the Extracellular Matrix (ECM) proteolysis. ECM breakdown causes air to get trapped in the alveoli, obstructing airflow. One step in curing COPD may be to convert inflammatory to pro-regenerative macrophages. Recently, decellularized ECM scaffolds have shown the ability to induce a pro-regenerative phenotype.

Yet these scaffolds are incapable for reaching the alveolar region of the lungs. To reach the alveolar region particles need a diameter of 1-5 μm or smaller than 300 …

Preparation And Application Of Catalysts For The Stereospecific Reduction And Photooxygenation Of Olefins In Continuous Operations: A Novel Method For The Production Of Artemisinin, Daniel C. Fisher

Theses and Dissertations

Over the last two centuries, the discovery and application of catalysts has had a substantial impact on how and what chemicals are produced.Given their broad significance, our group has focused on developing new catalyst systems that are recoverable and reusable, in an attempt to reduce concomitant costs.

Our efforts have centered on constructing a recyclable chiral heterogeneous catalyst capable of effecting asymmetric hydrogenations of olefins with high stereoselectivity. A class of phosphinoimidazoline ligands, developed by researchers at Boehringer-Ingelheim, known as BIPI ligands, have proven efficacious in the asymmetric reduction of alkenes. However, these chiral ligands are homogeneous and coordinated to …

The Effect Of Combined Sewer Overflows On The Abundance Of Antibiotic Resistance Genes And Bacteria In The James River, Enjolie Levengood

Theses and Dissertations

Antibiotic resistance is a major threat to human health. Clinical situations are the main focus for antibiotic resistance research, but understanding the spread of resistance in the environment is also vital. A major contributor to this spread is wastewater from combined sewer overflow (CSO) events. The effect of CSO events on antibiotic resistance in the James River near Richmond, Virginia was studied using genomic and microbiological approaches. The abundance of genes associated with resistance to quinolones (qnrA) and tetracycline (tetW) was strongly correlated with the presence of fecal indicator bacteria (E. coli abundance) as well …

The Effect Of Saha On The Expression Of Genes In Wild Type And Hdac2 Knockout Mouse Models And Its Potential Use As Treatment For Schizophrenia, Maryum K. Ijaz

Theses and Dissertations

The symptoms of schizophrenia have been categorized into three subsets including positive, negative, and cognitive symptoms. Although atypical antipsychotic use has shown promising reduction in positive and negative symptoms of schizophrenia, such as hallucination, delusions and flat affect, the cognitive subset of symptoms remains and has an adverse impact on those affected. Chronic treatment with the atypical/secondary antipsychotic clozapine is one example that has ameliorated hallucinations and delusions but results in cognitive memory deficits. When chronically given in conjunction with the HDAC inhibitor, SAHA, the cognitive memory deficits of mouse models decline. HDAC2KO mice were bred and used in chronic …

A Study Of Critical Value Notification In The Outpatient Setting: The Relationship Between Physician Response And Patient Outcomes, Kristie Renee Finney

Theses and Dissertations

Critical values are laboratory values that represent a life-threatening condition for which there is a treatment available. Laboratories make immediate notifications to ordering providers when critical values are identified so that they may quickly act to initiate a treatment for their patient. The majority of laboratories apply the inpatient critical value list to the outpatient setting, although there are many differences between an acutely ill inpatient population and an ambulatory outpatient population. The goal of this study was to determine if providers responded to the critical values in the outpatient setting and to determine if there was a difference in …

Skinface, Islam Shehab

Theses and Dissertations

Throughout history, skin manipulation was primarily practiced for cultural, tribal, or religious purposes. In the contemporary landscape, skin manipulation has been objectified and commercialized. This is exemplified through bio-upholstery, foreign materials under our skin and changing the skin structure.

This thesis investigates skin manipulation, with the intent to focus experimentation on the skin’s lines of cleavage, a topographical map drawn on our skin and used to define the direction where skin has the most and least flexibility. The aim is to connect and explore materials that can be used as a second skin, while at the same time examining and …

A Computational Study Of The Kinematics Of Femoroacetabular Morphology During A Sit-To-Stand Transfer, Brandon K. Marine

Theses and Dissertations

Computational modeling in the field of biomechanics is becoming increasingly popular and successful in practice for its ability to predict function and provide information that would otherwise be unobtainable. Through the application of these new and constantly improving methods, kinematics and joint contact characteristics in pathological conditions of femoroacetabular impingement (FAI) and total hip arthroplasty (THA) were studied using a lower extremity computational model. Patients presenting with FAI exhibit abnormal contact between the femoral neck and acetabular rim leading to surrounding tissue damage in daily use. THA is the replacement of both the proximal femur and acetabular region of the …

The Effects Of Disturbance And Species Specific Interactions On Diversity In An Agent Based Forest Simulation, Matthew E. Mills

Theses and Dissertations

In ecology literature, there is much data which suggests that conspecific negative density dependence (CNDD) and abiotic disturbances increase biodiversity in forests. This thesis elucidates the notion that not only do these two forces increase diversity, but they may also interact with one another in order to achieve higher levels of biodiversity. Abiotic disturbances, like fires and hurricanes, can indirectly impact conspecific effects because when these forces remove individuals from the landscape, the role of the conspecific effects will change. The interaction of these two factors in biodiversity are explored in an agent based forest simulation through a resource surface. …

Mathematical Models Of The Inflammatory Response In The Lungs, Sarah B. Minucci

Theses and Dissertations

Inflammation in the lungs can occur for many reasons, from bacterial infections to stretch by mechanical ventilation. In this work we compare and contrast various mathematical models for lung injuries in the categories of acute infection, latent versus active infection, and particulate inhalation. We focus on systems of ordinary differential equations (ODEs), agent-based models (ABMs), and Boolean networks. Each type of model provides different insight into the immune response to damage in the lungs. This knowledge includes a better understanding of the complex dynamics of immune cells, proteins, and cytokines, recommendations for treatment with antibiotics, and a foundation for more …

Comparing The Structural Components Variance Estimator And U-Statistics Variance Estimator When Assessing The Difference Between Correlated Aucs With Finite Samples, Anna L. Bosse

Theses and Dissertations

Introduction: The structural components variance estimator proposed by DeLong et al. (1988) is a popular approach used when comparing two correlated AUCs. However, this variance estimator is biased and could be problematic with small sample sizes.

Methods: A U-statistics based variance estimator approach is presented and compared with the structural components variance estimator through a large-scale simulation study under different finite-sample size configurations.

Results: The U-statistics variance estimator was unbiased for the true variance of the difference between correlated AUCs regardless of the sample size and had lower RMSE than the structural components variance estimator, providing better type 1 error …

Come Fly With Me: Using Amixicile To Target Periodontal Pathogens And Elucidating The Innate Immune Response In Drosophila Melanogaster, Kathryn Sinclair

Theses and Dissertations

Periodontal diseases (PD) affect 46% of American adults over age 30. These diseases cause symptoms including bleeding and swelling of the gums, bone resorption, and tooth loss, that affect quality of life and have a high economic burden. Periodontal diseases are caused by an imbalance in the oral microbiome, from a healthy state that contains anti-inflammatory commensals like Streptococcus gordonii and mitis, to a diseased state that has pro-inflammatory anaerobic pathogens including Porphyromonas gingivalis, Prevotella intermedia, Fusobacterium nucleatum, and Tannerella forsythia. The latter initiate disease progression in the oral cavity. However, it’s the host immune …

Big Data Visualization Platform For Mixed Reality, Aliakbar Panahi

Theses and Dissertations

The visualization of data helps to provide faster and deeper insight into the data. In this work, a system for visualizing and analyzing big data in an interactive mixed reality environment is proposed. Such a system can be used for representing different types of data such as temporal, geospatial, network graph, and high dimensional. Also, an implementation of this system for four different data types are created. The data types include network data, volumetric data, high dimensional, and spectral data for different mixed reality devices such as Microsoft HoloLens, Oculus Rift, Samsung Gear VR, and Android ARCore were created. It …

Nanopore Thermodynamics Via Infrared Laser Heating, Christopher Angevine

Theses and Dissertations

Single molecule nanopore spectroscopy is a label-free method for characterizing a wide variety of water-soluble molecules. Recently there have been efforts to expand nanopore sensing to new areas of study. Forensic investigators require an easy to deploy method to identify an unknown number of contributors in a solution. Currently there is no easily available method to distinguish between a single or multiple contributor solution of DNA before being processed by more advanced analytical techniques which has led to wasted time and resources increasing the backlog of samples waiting to be processed. In this work we present a new nanopore technique …

Ca2+/Calmodulin-Dependent Protein Kinase Type Ii (Camk-Ii) Is Required For Hematopoietic Stem Cell Specification, Camden E. Kurtz

Theses and Dissertations

Ca2+/Calmodulin-dependent protein kinase type II (CaMK-II) is a Serine/Threonine protein kinase that is activated by Ca2+ and Calmodulin to phosphorylate substrates involved in myriad developmental processes. This project implicates CaMK-II in specification of HSCs, and zebrafish provide an ideal embryonic model to study hematopoiesis. Zebrafish genetic manipulation was achieved through: incubation in chemical inhibitors; injection of notochord-targed WT and DN CaMK-II constructs with Transposase; and injection of camk2g1 translation-blocking morpholino antisense oligonucleotide (MO). Whole-mount in situ hybridization (WISH) and immunolocalization on zebrafish embryos allowed visualization of key HSC markers and pathway components that implicated CaMK-II in the specification of HSCs. …

Recovery From Design, Cassandra J. Ellison

Theses and Dissertations

Through research, inquiry, and an evaluation of Recovery By Design, a ‘design therapy’ program that serves people with mental illness, substance use disorders, and developmental disabilities, it is my assertion that the practice of design has therapeutic potential and can aid in the process of recovery. To the novice, the practices of conception, shaping form, and praxis have empowering benefit especially when guided by Conditional and Transformation Design methods together with an emphasis on materiality and vernacular form.

Role Of Mir-155 And Mir-146a In Mast Cell Function, Amina Abdul Qayum

Theses and Dissertations

Mast cells are resident immune cells abundantly found in the tissue at the host-environment interface, where they play a critical role in inflammatory allergic responses. Mast cell responses may be regulated by the cytokine milieu at the site of inflammation. Recent studies have revealed microRNAs to be important in altering cytokine signaling in immune cells. Here, we demonstrate for the first time that IL-10 and IL-33 induce miR-155 and miR-146a, respectively, to alter mast cell functions. We report that IL-10 enhanced IgE induced activation of mast cells. IL-10 effects are dependent on Stat3 activation, which elicits miR-155 expression, resulting in …

Distant Electric Vision: Cultural Representations Of Television From “Edison’S Telephonoscope” To The Electronic Screen, Ivy Roberts

Theses and Dissertations

Do inventions that exist only on paper have less credibility than functional technologies? How has the meaning and significance of audiovisual media and technology changed over time? This dissertation examines historiography and methodology for media history, arguing for an interdisciplinary approach. It addresses methodological issues in media history—media in transition, media archaeology, and film history—through an examination of television’s speculative era. It tackles moving-image history through an historical investigation of Victorian and Machine age “television”.

Because the concept and terminology of “television” changed dramatically during this period, I use the phrases “distant electric vision” and “seeing by electricity,” to define …

Provider Appearance: A Survey Of Guardian And Patient Preference, Joshua Westphal

Theses and Dissertations

Purpose: To understand guardian and child preferences for the appearance of their pediatric dentist. This was a cross-sectional descriptive study using survey methodology with patients and parents that attended the VCU Pediatric Dental clinic.

Methods: A total sample of 100 guardians and 97 pediatric patient participants completed the computer-based questionnaire. Four subjects were asked to pose for photographs wearing various combinations of attire (professional, casual, white coat, scrubs).

Results: Among guardians, 56% reported preferring a provider in scrubs, with white coat the second most preferred attire (39%) for their children. For pediatric patients, scrubs were still most often selected, …

Hub Proteins, Paralogs, And Unknown Proteins In Bacterial Interaction Networks, Neha Sakhawalkar

Theses and Dissertations

Proteins are the functional units of cells. However, a major portion of the proteome does not have a known functional annotation. This dissertation explores protein -protein interactions, involving these uncharacterized or unknown function proteins. Initially, protein – protein interactions were tested and analyzed for paralogous proteins in Escherichia coli. To expand this concept further and to get an overview, protein – protein interactions were analyzed using ‘comparative interactomics’ for four pathogenic bacterial species including Escherichia coli, Yersinia pestis, Vibrio cholerae and Staphylococcus aureus. This approach was used to study unknown function protein pairs as well as to …

Bridging The Empathy Gap: Effects Of Brief Mindfulness Training On Helping Outgroup Members In Need, Daniel R. Berry

Theses and Dissertations

Witnessing others in need can be felt similarly to experiencing it oneself (empathy) and motivates assistance of those in need (prosocial action). It is well-documented that empathy can occur automatically, but when those in need are not members of a social ingroup, empathy and prosocial action are undermined. One major ingroup—outgroup division in American and in other countries is based on race. Although most condemn racial discrimination, empathy and prosocial action are often lower, however unintentionally, in interracial contexts. In light of this empathy gap, it is important to identify psychological factors that could bolster empathy and prosocial action toward …

A Comparative Study Of Intraradicular Enterococcus Faecalis Biofilm Removal With Three Root Canal Treatment Systems: A Scanning Electron Microscopy Evaluation, Cyrous Ardalan

Theses and Dissertations

The objective of this study was to evaluate the biofilm removal efficacy of three root canal treatment systems: ProUltra® PiezoFlow™, traditional needle irrigation, and the GentleWave® system in an ex-vivo benchtop study. Twenty-four extracted maxillary and mandibular molars were selected. Teeth were all instrumented to a master apical file size #25 with 4% taper. Teeth were then randomly divided into four experimental groups and two control groups. The root canals were inoculated with a culture of Enterococcus faecalis and incubated for five weeks to form a biofilm. Each group was then treated with one of the different root canal treatment …

Good As We Know It: Goodness In Design Discourse Since 1870, Garreth C. Blackwell

Theses and Dissertations

This dissertation examines the ways in which design and design practitioners have defined value in the design discourse through the vocabulary and concept of goodness since 1870. These definitions of value have been central to design discourse both past and present and deal with the impact and purpose of design work as well as its role in the creation of the approaching future. Since before the coalescence of graphic design as a separate field of design, these questions have been tied to the form, function or social impact of the objects created by designers. Despite the prevalence of this line …

Tumor-Intrinsic Inflammatory Pathways Associated With Tumor Dormancy And Recurrence, Savannah E. Butler

Theses and Dissertations

The successful treatment of breast cancer is limited due to a fraction of tumor cells escaping drug-treatment by entering a dormant state, only to relapse years or decades later at distant sites. Host-driven chronic inflammatory cells such as M2 macrophages play an important role in tumorigenesis, but the role of tumor-intrinsic inflammatory signaling involved in tumor dormancy and recurrence is unknown. We sought to determine the role of tumor-intrinsic inflammatory pathways in mouse mammary carcinoma cells (MMC) treated with Adriamycin (ADR), a clinically relevant chemotherapeutic drug. We found that ADR-induced dormant tumor cells autonomously produced pro-inflammatory cytokines, in vitro. …

Inhibition Of Oxidative And Conjugative Metabolism Of Buprenorphine Using Generally Recognized As Safe (Gras) Compounds Or Components Of Dietary Supplements, Neha V. Maharao

Theses and Dissertations

This dissertation aimed at developing an inhibitor strategy to improve the oral bioavailability (F_oral) and systemic exposure (AUC_∞) of buprenorphine (BUP) as well as reduce the variability associated with them. Twenty-seven generally recognized as safe (GRAS) compounds or dietary substances were evaluated for their potential to inhibit the oxidative and conjugative metabolism of BUP, using pooled human intestinal and liver microsomes. In both the organs, oxidation appeared to be the major metabolic pathway with a 6 fold (intestine) and 4 fold (liver) higher intrinsic clearance than glucuronidation. Buprenorphine was predicted to show low and variable F …

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. …

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 …