Digital Commons Network^™

Investigating The Molecular Etiologies Of Sporadic Als (Sals) Using Rna-Sequencing, David G. Brohawn

Theses and Dissertations

ALS is an often lethal disease involving degeneration of motor neurons in the brain and spinal cord. Current treatments only extend life by several months, and novel therapies are needed. We combined RNA-Sequencing, systems biology analyses, and molecular biology assays to elucidate sporadic ALS group-specific differences in postmortem cervical spinal sections (7 sALS and 8 control samples) that may be relevant to disease pathology. >55 million 2X150 RNA-sequencing reads per sample were generated and processed.

In Chapter 2, we used bioinformatics tools to identify nuclear differentially expressed genes (DEGs) between our two groups. Further, we used Weighted Gene Co-Expression Network …

"They Believe That Because They Are Women, It Should Be Easier For Them." Subtle And Overt Sexism Toward Women In Stem From Social Media Commentary, Katherine Hall

Theses and Dissertations

This study implemented a social media based content analysis to examine the subjective experiences and the current public perceptions of sexism in STEM fields. Participants included men and women who a) identified as either in STEM or not identified as in STEM and b) commented through Facebook on HuffPost Women articles about women in STEM. The analysis indicated that sexism remains an issue for women in STEM careers. Women in STEM identified several gender-based challenges that they have experienced; some participants discussed how they handled those challenges. Men both in and not in STEM were less likely to acknowledge and …

Identification Of Size And Shape Changes In Orofacial Development And Disease, Allyson E. Kennedy

Theses and Dissertations

Among the most prevalent and devastating types of human birth defects are those affecting the mouth and face, such as orofacial clefts. Children with malformed orofacial structures undergo multiple surgeries throughout their lifetime and struggle with facial disfigurements, speech, hearing, and eating problems. Therefore, facilitating new research in cranio- and orofacial development is paramount to prevention and treatment of these types of birth defects in humans. Xenopus laevis has emerged as a new tool for dissecting the mechanisms governing facial development. Thus, molecular analyses accompanied by quantitative assessment of morphological changes during orofacial development of this species could be very …

The Microbiome In Light Of Host Evolution, Alexander M. Waldrop Jr.

Theses and Dissertations

Recent advances in sequencing technologies have provided an unprecedented window in the unseen biological world. Accompanying this revolution is a growing appreciation for the ubiquity and diversity of beneficial interactions between animals and the microbes they carry. Given the symbiotic roles of microbes in host nutrition, immunity, behavior, development, and nearly every other facet of host biology, it is becoming increasingly clear that any understanding of hosts and their evolution would be incomplete without also considering the microbial dimension. Yet despite the growing body of evidence that many of these partnerships are rooted deep in evolutionary time, the majority of …

Jpg Artifacts, Abbey Lee Sarver

Theses and Dissertations

This thesis examines my artistic practice over the past two years at Virginia Commonwealth University, which has led to the installation of my thesis exhibition, JPG Artifacts. My work inspects the current process of image making within a responsive studio practice of deconstructing the digital image into a physical space. While my thesis exhibition is just one culminating formal installation of my experimental studio practice, this paper will examine some main points of reference towards what has led me to the most present public iteration of my work. I hope to position my research in context of contemporary art and …

Ink On Paper, Matthew T. Warren

Theses and Dissertations

This thesis establishes the sources and potential solutions for my fractured and often contentious relationship with photography. The anxieties of contemporary artists working with photographic vocabularies are manifest and the tools to consider and critique this work is evasive and lacking. This text is both support and companion to my exhibition.

Genome Wide Epigenetic Analyses Of Araptus Attenuatus, A Bark Beetle, Chitra Seshadri

Theses and Dissertations

Phylogeographic studies have relied on surveying neutral genetic variation in natural populations as a way of gaining better insights into the evolutionary processes shaping present day population demography. Recent emphasis on understanding putative adaptive variation have brought to light the role of epigenetic variation in influencing phenotypes and the mechanisms underlying local adaptation. While much is known about how methylation acts at specific loci to influence known phenotypes, there is little information on the spatial genetic structure of genome-wide patterns of methylation and the extent to which it can extend our understanding of both neutral and putatively adaptive processes. This …

A Neural Circuit Of Appetite Control In C. Elegans, Kristen C. Davis

Theses and Dissertations

Feeding behavior and its associated neural circuitry is complex and intricate in mammalian systems, however, a simple model organism, such as C. elegans provides a more basic approach to understand factors and molecules involved. The fruit-dwelling nematode provides a unique set of resources; it only consists of 959 cells, 302 of which are neurons. In addition, each neuron’s connectivity and position within the worm is known and consistent between animals. Conservation of neurotransmitters and biochemical processes add to this impressive list. These resources provide an excellent background to address feeding behavior and the neural structures governing it.

Feeding behavior in …

Courageous Solstice: Reconstructing Fairy Tales For A Black Youth Aesthetic, Tanya Boucicaut

Theses and Dissertations

This thesis interrogates the historical, philosophical, and existential implications of the Black Arts Movement and its major artists on the recurring themes of social injustice, Western hegemony, and the fight for aesthetic authenticity to reimagine fairy tales for the youth Black Aesthetic. As a personal reflection and foundational document for a larger project, this work weaves these implications through the practical application of the varied stages of program development for youth artists. This project also is a handbook that encompasses scholarly research, reflective analysis and anecdotal journal evidence. The subsequent chapters explore the theological and theatre pedagogical educational influences that …

Meta-Analytic Estimation Techniques For Non-Convergent Repeated-Measure Clustered Data, Aobo Wang

Theses and Dissertations

Clustered data often feature nested structures and repeated measures. If coupled with binary outcomes and large samples (>10,000), this complexity can lead to non-convergence problems for the desired model especially if random effects are used to account for the clustering. One way to bypass the convergence problem is to split the dataset into small enough sub-samples for which the desired model convergences, and then recombine results from those sub-samples through meta-analysis. We consider two ways to generate sub-samples: the K independent samples approach where the data are split into k mutually-exclusive sub-samples, and the cluster-based approach where naturally existing …

Role Of Free Fatty Acid Receptors In The Regulation Of Brain-Derived Neurotrophic Factor Levels In The Enteric Glial And Endocrine Cells, Reem M. Alkahtani

Theses and Dissertations

Recent deorphanization of several G-protein-coupled receptors (GPRs) as endogenous receptors for free fatty acids (FFAs) has increased our understanding of these nutrients as signaling molecules and the integral role of gut microbiota in the regulation of host defense mechanisms, energy metabolism, gastrointestinal motility and secretion. There are five distinct FFA receptors (FFRAs: FFAR1, FFAR2, FFAR3, FFAR4 and GPR84) that differ in molecular structure, ligand specificity, expression pattern, and functional properties. FFARs are grouped according to the chain length of FFAs that activate each FFAR.

Enteric glial cells and enteroendocrine cells play a pivotal role in the secretion of gliotransmitters and …

Ancient Puebloan Human Effigy Vessels: An Examination Of Iconography And Tradition, Amy G. Marshman

Theses and Dissertations

This dissertation provides an iconographic interpretation of a group of Ancient Puebloan human effigy vessels and fragments from the American Southwest, dating to the Pueblo II period, c. 900 -1150 CE. Initially, this project focuses on Ancient Puebloan human effigy vessels from three specific collections; a single vessel in the collection of the National Museum of the American Indian in Washington, D.C., a human effigy vessel in the collection of the American Museum of Natural History in New York, and the so-called Putnam Human Effigy Jar from Chaco Canyon at the Peabody Museum of Archaeology and Ethnology at Harvard University. …

Differential Reactivity Of Microglia In Two Mouse Models Of Multiple Sclerosis, Rebecca K. Hartley

Theses and Dissertations

Multiple sclerosis (MS) is a neurodegenerative disorder characterized by CNS inflammation and axonal demyelination. In addition, axonal pathology has also been reported in MS and may be responsible for the functional deficits associated with this disease. Based on preliminary data from our laboratory, we propose that a specific domain of the neuron, known as the axon initial segment (AIS), is targeted in MS. Consistent with our work from the human tissue, we have also observed disruption of AIS integrity in a murine CNS inflammatory model and observations strongly implicate reactive microglia as mediators of AIS disruption. In contrast, a murine …

Effects Of Traumatic Brain Injury On Oxycodone Reinstatement And Physical Dependence, Neil B. Varshneya

Theses and Dissertations

Epidemiological data indicate that patients who experience a traumatic brain injury (TBI) have an elevated risk of developing a substance use disorder (SUD), but the underlying neurobiological connections remain unclear. To further understand the relationship between TBI and SUD, we investigated the effects of TBI on the abuse-related effects of oxycodone in preclinical models. Our evaluation utilized a lateral fluid percussion injury of moderate severity in adult male Sprague-Dawley rats. In the first aim, we tested the hypothesis that moderate TBI increases the risk for relapse to an opioid use disorder as measured by reinstatement of lever-pressing behavior following extinction …

Resolution Of Inflammation Rescues Axon Initial Segment Disruption, Nicholas M. George

Theses and Dissertations

Axonal domains are required for proper neuron function. These domains are unstable and degenerate concurrent with the inflammation in multiple sclerosis (MS) and the inflammatory disease models experimental autoimmune encephalomyelitis (EAE) and lipopolysaccharide (LPS) induced inflammation. Previous studies from our laboratory have shown that the axon initial segment (AIS) is maintained independently of the presence of myelin, but that AIS disruption is seen in MS as well as EAE and LPS-mediated inflammation. AIS loss can be interrupted in the early stage of EAE using the anti-inflammatory drug Didox. However, the potential for Didox directed repair of the AIS in later …

Free & Content, Victoria M. Ahmadizadeh

Theses and Dissertations

I draw on my natural interest in my family’s eclectic collections – both traditional and personal – to create poetic portraits composed of carefully made and arranged objects. The goal of my portraiture is not to convey physical likeness; superseding the imitation of appearance is psychological portrayal of the desires and disappointments of the sitter. Often, a fragmented sense of self is revealed – both in others and in myself – and I seek to depict the kaleidoscopic nature of individuals in their given situations. Possessing whimsical, playful elements as well as encounters with lack and longing, I create work …

Behavioral Phenotyping Of Vmat1 Knockout Mice: Relevance To Neuropsychiatric Disorders, Kevin A. Webster Ph.D.

Theses and Dissertations

Schizophrenia is a debilitating mental disorder that causes a large economic burden and is prevalent across all cultures and countries around the world. Although both environmental factors and genetics are known to play an important role in the etiology of schizophrenia, the exact role of genetics and its interaction with environmental factors in an individual’s predisposition to develop schizophrenia is poorly understood. Schizophrenia is characterized by symptoms that include positive symptoms (e.g. delusions, hallucinations, disorganized thinking and speech), negative symptoms (e.g. avolition, anhedonia, depressive-like behavior), and cognitive dysfunctions (e.g. executive functioning deficits in learning and memory, attention, and vigilance). Genomic …

Fabrication Of Multifunctional Nanostructured Porous Materials, Ahmed A. Farghaly

Theses and Dissertations

Nanostructured porous materials generally, and nanoporous noble metals specifically, have received considerable attention due to their superior chemical and physical properties over nanoparticles and bulk counterparts. This dissertation work aims to develop well-established strategies for the preparation of multifunctional nanostructured porous materials based on the combination of inorganic-chemistry, organic-chemistry and electrochemistry. The preparation strategies involved one or more of the following processes: sol-gel synthesis, co-electrodeposition, metal ions reduction, electropolymerization and dealloying or chemical etching. The study did not stop at the preparation limits but extended to investigate the reaction mechanism behind the formation of these multifunctional nanoporous structures in order …

Identifying Profiles Of Resilience Among A High-Risk Adolescent Population, Anna W. Wright

Theses and Dissertations

The purpose of the present study was to determine whether distinct patterns of adolescent adjustment existed when four domains of functioning were considered. The study included a sample of 299 high-risk urban adolescents, predominantly African American, ages 9-16 and their maternal caregivers. Cluster analysis was used to identify patterns of adjustment. Logistic regression analyses were used to explore whether variations in levels of five theoretically and empirically supported protective factors predicted cluster membership. A four-cluster model was determined to best fit the data. Higher rates of goal directedness and anger regulation coping predicted membership within the highest functioning cluster over …

Loneliness, Cynical Hostility, And Cognitive Decline In Americans Above Age 50, Sarah C. Griffin

Theses and Dissertations

Background. Research identifies isolation (being alone) as a risk factor for cognitive decline— yet it is possible that subjective dimensions of isolation are more critical. Potential risk factors are loneliness (the distress stemming from feeling alone) and cynical hostility (an attitude of distrust and cynicism). The present study examined the relationship between these factors and cognitive functioning and decline.

Methods. Data came from the Health and Retirement Study, a nationally representative longitudinal study of US adults over 50. Loneliness was measured using the Hughes Loneliness Scale; cynical hostility was measured using items from the Cook-Medley Hostility Inventory. Cognitive functioning was …

Hidden In Plain Sight: Image, Text, And Social Commentary In Victor Ekpuk's Cartoons For The Daily Times Of Nigeria, 1989-1998, Kaleb W. Jewell

Theses and Dissertations

This thesis provides an analysis of the cartoons produced by Victor Ekpuk for The Daily Times newspaper of Nigeria from 1989 through 1998 and the artist’s use of ancient nsibidi script to “hide in plain sight” his social commentaries on sociopolitical and economic issues in Nigeria. Victor Ekpuk’s original cartoons within the permanent collection of the Smithsonian Institution’s National Museum of African Art are examined in the context of indigenous masking practices and other indirect methods employed by indigenous comedians to protect themselves. Moreover, the cartoons’ use of caricature and their nsibidi scripts within are argued to provide a connotative …

Some Form Of Blue, Zena A. Zakanycz

Theses and Dissertations

Through my art process and material selection, I investigate how interior spaces long to accumulate memories and possessions. I am interested in encroaching floor to ceiling build-up of collected goods kept in the homes of individuals unable to discard or part with possessions. These individual’s daily movements through their space and their denial of the surrounding mass informs my work. My work is larger than human scale, made of multiple units, and dense; yet understated by the subtle use of color and repeated materials. When I make an installation it often begins with creating a wall or a floor that …

Growth And Characterization Of Wide Bandgap Quaternary Bemgzno Thin Films And Bemgzno/Zno Heterostructures, Mykyta Toporkov

Theses and Dissertations

This thesis reports a comprehensive study of quaternary BeMgZnO alloy and BeMgZnO/ZnO heterostructures for UV-optoelectronics electronic applications. It was shown that by tuning Be and Mg contents in the heterostructures, high carrier densities of two-dimensional electron gas (2DEG) are achievable and makes its use possible for high power RF applications. Additionally, optical bandgaps as high as 5.1 eV were achieved for single crystal wurtzite material which allows the use of the alloy for solar blind optoelectronics (E_g>4.5eV) or intersubband devices.

A systematic experimental and theoretical study of lattice parameters and bandgaps of quaternary BeMgZnO alloy was performed for …

Influence Of Historic Landscapes And Contemporary Species Management On Chesapeake Bay Bald Eagles And Osprey, Catherine B. Viverette

Theses and Dissertations

Influence of historic landscapes and contemporary species management on Chesapeake Bay Bald Eagles and Osprey

Catherine B. Viverette

Co-distributed species with well documented demographic histories can provide good models for testing alternative hypotheses about the impact of evolutionary history, contemporary landscapes, and species management on current distribution and population structure. The Osprey (Pandion haliaetus) and Bald Eagle (Haliaeetus leucocephalus) have been extensively studied, managed and monitored across their North American breeding range, particularly in the Chesapeake Bay. We used a combination of ecological niche modelling, diet reconstruction, and population genetic modeling to understand the role of …

Beyond Conventional C-Plane Gan-Based Light Emitting Diodes: A Systematic Exploration Of Leds On Semi-Polar Orientations, Morteza Monavarian

Theses and Dissertations

Despite enormous efforts and investments, the efficiency of InGaN-based green and yellow-green light emitters remains relatively low, and that limits progress in developing full color display, laser diodes, and bright light sources for general lighting. The low efficiency of light emitting devices in the green-to-yellow spectral range, also known as the “Green Gap”, is considered a global concern in the LED industry. The polar c-plane orientation of GaN, which is the mainstay in the LED industry, suffers from polarization-induced separation of electrons and hole wavefunctions (also known as the “quantum confined Stark effect”) and low indium incorporation efficiency that …

Optical Investigations Of Ingan Heterostructures And Gesn Nanocrystals For Photonic And Phononic Applications: Light Emitting Diodes And Phonon Cavities, Shopan D. Hafiz

Theses and Dissertations

InGaN heterostructures are at the core of blue light emitting diodes (LEDs) which are the basic building blocks for energy efficient and environment friendly modern white light generating sources. Through quantum confinement and electronic band structure tuning on the opposite end of the spectrum, Ge_1−xSn_x alloys have recently attracted significant interest due to its potential role as a silicon compatible infra-red (IR) optical material for photodetectors and LEDs owing to transition to direct bandgap with increasing Sn. This thesis is dedicated to establishing an understanding of the optical processes and carrier dynamics in InGaN heterostructures for achieving …

Cajamarca Ceramic Spoons From Northern Peru: Forming A Symbolic Function, Jeanette Louise Nicewinter

Theses and Dissertations

Ten painted Cajamarca-style ceramic spoons form the foundation for an investigation of the way that these seemingly utilitarian objects were bestowed with economic and symbolic value both within and outside of the borders of the Cajamarca region, located in the north highlands of present-day Peru. Since the ceramic spoons have been recovered from sites associated with large and powerful societies and states, such as the Moche of the north coast and the Wari of the central highlands, an analysis of the form, style and imagery present on these spoons reveals how these objects transcended cultural boundaries. To assess and evaluate …

Allegories Of The Modern: The Female Nude In Art Nouveau, Emily Winthrop

Theses and Dissertations

Modernism is a plurality, not a singular concept. This project explores examples of Art Nouveau nudes to describe the particular expressions of the modern through varied and complicated allegorical bodies. The female nude as a nexus for ideals of gender, art, and beauty, is informed by and constructs the understanding of these ideals within society. Art Nouveau thus employed the nude to represent complex manifestations of modernity. Three diverse cases provide the subjects of each chapter. All explore modernism through objects and interiors, in public and private environments, and each connects the decorative arts with accounts of European modernism in …

The Modification Of Silica Aerogel Materials For Contemporary Use, Lauren White

Theses and Dissertations

Aerogel materials have had limited utility due to their fragility, geometrical limitations, fabrication costs and protracted fabrication times. The objective of this project was to eliminate these limitations. Native, cross-linked and hybrid aerogel monoliths have been fabricated using a newly developed one-pot method without the need for solvent exchange. The key to this technique is the use of an ethanol–water azeotrope mixture, which contains 4.4% water by volume, as both a gelation and supercritical drying solvent. The small water content allows for drying at temperatures close to the supercritical temperature of the dry solvent, where reactions such as silica dissolution …

Causes And Consequences Of Peer Victimization Among Adolescents With Autism, Sarah T. Doyle

Theses and Dissertations

A significant, yet understudied issue that demands attention is the experience of peer victimization among adolescents with autism spectrum disorders (ASDs). Research indicates that youth with disabilities, including those with ASDs, are victimized more frequently as compared to their typically developing peers. However, little is known about the peer victimization experience for adolescents with ASDs beyond its frequency of occurrence. This study examined relations between peer victimization and individual, peer, and parent factors and outcomes including internalizing and externalizing symptoms among adolescents with ASDs. No significant indirect effects were found for peer victimization on relations between individual social-cognitive and emotion …