Digital Commons Network^™

Synaptic Plasticity In A Visual Cortical Region Induced By Early-Deafness, John M. Kay

Theses and Dissertations

When organisms learn and adapt to their environment or lose a sensory modality, neurons in the brain undergo a cellular process called ‘plasticity.’ This thesis explores the loss of a non- visual system (early deafness) and how it can affect visual plasticity. To examine this question, Golgi-stained cortical neurons were studied from the visual region PLLS from early-deaf cats and their hearing controls. Dendritic spine density and dendritic spine diameter are well-known indicators of synaptic plasticity and these neuronal features were measured using light microscopic techniques and Neurolucida. Within the visual PLLS, the mean spine density for the deaf cats …

From The Margins To The Center: Legitimation Strategies From An Alt-Right Case Study, Lauren C. Garcia

Theses and Dissertations

Despite a growing interest in understanding Donald Trump’s election in 2016 as part of the historical trajectory of white racial identity politics, we do not know much about how ideas deemed “radical right” become mainstreamed. My study builds on extant research that implicates the emergence of the think tank industry by viewing one such right wing think tank as a racialized organization. My analysis focuses on the organizational strategies of the National Policy Institute (NPI). Google searches for NPI spiked in 2016 with their vocal support of Trump and visible organizing in D.C. Using Williams’ (2018) theoretical framework of organizational …

Modeling The Evolution Of Barrier Islands, Greg Robson

Theses and Dissertations

Barrier islands form off the shore of many coastal areas and serve as the first line of defense, protecting littoral communities against storms. To study the effects that climate change has on barrier islands, we use a cellular model of wind erosion, surface dynamics, beach dynamics, marsh dynamics, and vegetation development. We will show the inhibition of movement when vegetation is present.

Sensory Substitution, Key To Inclusive Learning, Fathima Z. Zahir

Theses and Dissertations

Visually impaired students, in primary education, encounter unique challenges while learning creative skills, exploring artistic expression and developing problem-solving skills, because so much instructional content is delivered visually. Sensory substitution—an approach that replaces visual information with feedback from other intact senses like touch, sound, taste or smell—provides an opportunity to address those challenges.

Through the use of sensory substitution, this thesis proposes concrete ways to capitalize on the enhanced abilities of visually impaired primary school students. The research outcome of this thesis is a system of templates that puts these enhanced abilities to work for visually impaired students, to support …

Investigating The Role Of Oncogene C-Terminal Binding Protein (Ctbp) In Pancreatic Ductal Adenocarcinoma, Kranthi Kumar Chougoni

Theses and Dissertations

The transcriptional coregulator CtBP2 has been implicated as an oncogene in colon, prostate, breast and ovarian cancers. Previously, we reported overexpression of CtBP2 in human PDAC specimens. However, its exact role in PDAC is still unclear. In the current study, we attempt to delineate the oncogenic role CtBP2 in PDAC growth and metastasis. Using an orthotopic syngeneic pancreatic tumor mouse model (CKP), we found that deletion of Ctbp2 decreases PDAC tumor growth, proliferation, metastasis, EMT and significantly prolongs survival. Further, we identified significant downregulation of Erbb3 mRNA levels upon deletion of Ctbp2 in CKP PDAC cells As ErbB3 signaling was …

Strategies And Devices For Improving Respiratory Drug Delivery To Infants And Children With Cystic Fibrosis, Karl Bass

Theses and Dissertations

Cystic Fibrosis (CF) is a degenerative disease, which causes thickening of the airway surface liquid and reduced mucociliary clearance, which provides an ideal habitat for bacterial infections. Early treatment of CF in children can prevent chronic infection, improve quality of life, and increase life expectancy. The most predominant bacteria found in CF-diseased lungs is Pseudomonas aeruginosa (Pa), which can be treated with inhaled tobramycin. Excipient enhanced growth (EEG) powder formulations are well suited for administering tobramycin to children, as the EEG approach provides minimal upper airway loss and targeted drug delivery. This method uses an initially small aerosol for high …

Three Studies Of Research-Based Pedagogy In Physical Chemistry: Development Of A Zno Thin Film Experiment, Analysis Of Student Discourse By Graph Theory And Cognitive Engagement, Building A Physical Chemistry Faculty Network., Dilhara Liyanage

Theses and Dissertations

Three research projects, each focusing on a different aspect, development of a ZnO thin film experiment, student’s cognitive engagement behavior, and building of a faculty network, are presented in this dissertation.

In the first project, a physical chemistry laboratory experiment was developed to answer the question, “How do electrons move in a solid?”. The experiment structure follows the POGIL-PCL (Process Oriented Guided Inquiry Learning - Physical Chemistry Laboratory) model. Students begin by using the PhET “Quantum Bound States” animation to compare energy levels for single atoms to energy levels of a lattice containing many potential wells, and they incorporate that …

Mathematical Models Of Cellular Signaling And Supramolecular Self-Assembly, Pratip Rana

Theses and Dissertations

Synthetic biologists endeavor to predict how the increasing complexity of multi-step signaling cascades impacts the fidelity of molecular signaling, whereby cellular state information is often transmitted with proteins diffusing by a pseudo-one-dimensional stochastic process. We address this problem by using a one-dimensional drift-diffusion model to derive an approximate lower bound on the degree of facilitation needed to achieve single-bit informational efficiency in signaling cascades as a function of their length. We find that a universal curve of the Shannon-Hartley form describes the information transmitted by a signaling chain of arbitrary length and depends upon only a small number of physically …

Internalizing Data Collection: Personal Analytics As An Investigation Of The Self, Neal R. Swisher

Theses and Dissertations

Personal analytics, aka self-tracking, is the practice of using a digital device to track aspects of behavior, such as exercise habits, heart rate, sleep patterns, location, diet, and a host of other data points. This dissertation is an exploration of “self” in self-tracking, informed by theories of subjectivity, autonomy, power and knowledge. As a technological intervention, self-tracking devices change how we experience our own body and behavior. They also serve as methods to digitize human behavior. This data is combined with other data and processed using computational methods. Self-tracking devices are both personal and bureaucratic. They are devices used for …

Examining Body Mass Index And Sepsis Mortality At One Year After Sepsis, Jamie D. Robinson

Theses and Dissertations

Introduction: Sepsis is a serious and life-threatening syndrome affecting 1.7 million Americans annually and resulting in approximately 270,000 deaths. An “obesity paradox” where obese individuals have lower sepsis mortality than their non-obese counterparts has been described. The problem is that the longevity of the effect is unknown, and few studies have examined the obesity paradox after 1-2 months post-diagnosis.

Methods: This retrospective cohort study examined clinical, demographic, and biomarker variables thought to affect sepsis mortality at three-time points: 30 days, 180 days, and at one year post-sepsis diagnosis in order to shed light on specific factors that might define …

Regulation Of Vascular And Lymphatic Endothelial Barrier Function By Sphingosine-1-Phosphate, Jacqueline Bellaci

Theses and Dissertations

Endothelial cells play an important role in maintaining homeostasis, and disruption of the endothelial barrier have been linked to a number of different pathologies, including cancer metastasis. The vascular endothelial barrier is known to be regulated by a variety of factors, including sphingosine-1-phosphate (S1P), a bioactive lipid metabolite, which has been shown to improve barrier function. However, most studies to date have been focused on the vascular endothelium, and the regulation of the lymphatic endothelial barrier has not been thoroughly investigated. We found that prior to any stimulation the lymphatic endothelial cells (LECs) had a lower trans-endothelial resistance (TER) in …

Martian Mother, Elizabeth Mcgrady

Theses and Dissertations

This paper examines the relationship between humans and land, through the lens of the scientific and religious, bridging the physical realm with the spiritual. It acts as accompanying material to the project titled Martian Mother, supplementary information to the visual work, and an extension of the proposal, the center of the work. The proposal exists to send myself, or a like-minded individual, to Mars with artificial insemination equipment to give birth to the first Martian, becoming the first Martian Mother. This work is rooted firmly in speculative fiction, creating a nonlinear future framework for a new society and space exploration.

Spit In My Mouth: Queer Intimacies, Material Intra-Actions, And Sensuous Becoming, Gm Keaton

Theses and Dissertations

This document describes my multidisciplinary art practice as it intersects with New Materialism, Queer and Affect theory, Ecology, and my embodied and experiential knowledge as a queer subject. The writing is divided into two categories. One is more theoretical, thinking through these different discourses. The other realizes them through relationships and intra-actions between my material kin and me. With these two modes of writing,I propose that embodied and felt knowing is as valid and illuminating as more traditional forms of knowledge. These sections are interdependent and resist linear logic, offering relational meanings to each reader as they find their way …

Structural Features Contributing To Methylenedioxypyrovalerone (Mdpv) Analog Inhibition Of The Human Dopamine Transporter, Zachary R. Spires

Theses and Dissertations

Monoamine transporters (MATs) are transmembrane neurotransmitter sodium symporters consisting of the dopamine, norepinephrine, and serotonin transporters: DAT, NET, and SERT, respectively. Following an action potential and neurotransmitter vesicular release, MAT-mediated reuptake of these neurotransmitters in the presynaptic membrane contributes to the termination of monoaminergic neurotransmission. MATs are the targets of many drugs providing therapeutic benefits or taken recreationally. One of these drugs is methylenedioxypyrovalerone (MDPV), an abused synthetic cathinone that is a high potency uptake inhibitor of the human DAT (hDAT). In contrast, MDPV is a low potency uptake inhibitor of the Drosophila melanogaster dopamine transporter (dDAT). The reasons for …

On-Demand Electrically Induced Decomposition Of Thin-Film Nitrocellulose Membranes For Wearable Or Implantable Biosensor Systems, Benjamin M. Horstmann

Theses and Dissertations

Implantable or subcutaneous biosensors used for continuous health monitoring have a limited functional lifetime requiring frequent replacement and therefore may be highly discomforting to the patient and become costly. One possible solution to this problem is use of biosensor arrays where each individual reserve sensor can be activated on-demand when the previous one becomes inoperative due to biofouling or enzyme degradation. Each reserve biosensor in the array is housed in an individual Polydimethylsiloxane (PDMS) well and is protected from exposure to bodily fluids such as interstitial fluid ( ISF) by a thin-film nitrocellulose membrane. Controlled activation is achieved by decomposing …

Machine Girl, Yutong Liu

Theses and Dissertations

Machine girl is a character that mimics biology, labor, and humanity.

She relates to machine sympathy and machine learning; She is updating and processing of big data. During the interaction between me and the machine, I found you --- Machine girl.

Machine girl is a brilliant girl. She is an excellent translator and communicator, which is determined by her ability for machine learning. The cyber living space gives her a fundamental learning gift with a mathematical algorithm. She uses this gift to mimic everything from the human brain. She is not reasonable but sensitive. There are many different versions of …

Development Of A Torque-Based Device For The Quantification Of Arm Rigidity In Patients With Parkinson’S Disease, Georgina O. Miller

Theses and Dissertations

Parkinsonian rigidity is caused by the inability of the muscles to relax and extend properly, due to reduced dopamine levels and often begins on one side of the body before spreading contralaterally. The current standard for determining joint rigidity in a clinical setting is a test completed by the clinician based on the feel of the relaxed wrist and elbow joints as they are passively flexed and extended and a series of ordinal rating scales, the Movement Disorder Society’s – Unified Parkinson’s Disease Rating Scale (MDS-UPDRS), Hoehn and Yahr Scale (H&Y), and Parkinson’s Disease Questionnaire-39 (PDQ-39). These methods are used …

A Qualitative Analysis Of Caregiver Goals For Urban Children With And Without Asthma, Megan M. Carlson

Theses and Dissertations

Pediatric asthma is a major public health concern that disproportionately affects children of color and youth living in low-income, urban areas. The implications for public health, child health, and family functioning necessitates our understanding and addressing experiences by families who are facing barriers within their socio-demographic context in addition to the stressors associated with managing pediatric asthma. The current study applied qualitative methods to interviews with caregivers of children with and without asthma in an effort to more deeply connect with caregivers’ experiences and yield richer information about the intersection of identities as Black caregivers living in an urban setting …

Reaction Profiling Of Extracellular Protein Phosphorylation Through A Microfluidic Reactor Coupled With Raman Spectroscopy, Abigail Casey

Theses and Dissertations

Diseases and disorders in the human body are considered abnormalities of proper cellular function. Understanding the signal transduction mechanisms that cause these abnormalities is crucial to developing earlier detection methods, better treatment options and effective cures. While current diagnostic procedures are powerful tools in diagnosing diseases, they are ineffective in informing physicians on the real-time behavior of the signal transduction mechanisms associated with diseases and disorders. Currently, disease progression is monitored over time through routine patient visits and testing by one or more of the above techniques. By developing an approach that can monitor structural and conformational changes of proteins …

Dendrimer-Based Therapeutic Delivery Vehicle For The Treatment Of Ocular Diseases, Remy C. Cooper

Theses and Dissertations

The treatment of ocular diseases poses a significant challenge to drug delivery design, due to the eye’s complex anatomy, with a semi-permeable blood-ocular barrier and associated immune privilege. To address some of the delivery challenges, polycationic dendrimers are explored as vehicle for the treatment of posterior chamber disease. Dendrimers are a class of polymeric nanoparticles that are highly branched, multivalent and monodisperse, whose three-dimensional globular architecture has given them the nickname of “synthetic proteins”. Dendrimers are synthesized by reacting monomers in a step-wise fashion to produce generationally and radially increasing structures, with core, interior and surface chains that are highly …

Characterization Of The Gonococcal Calprotectin Zn-Acquisition System, Tdfh, And The Efficacy Of Metal Starvation For Treating Gonococcal Disease, Michael T. Kammerman

Theses and Dissertations

Abstract

Characterization of the Gonococcal Calprotectin Zn-Acquisition System, TdfH, and the Efficacy of Metal Starvation for Treating Gonococcal Disease.

By Michael T. Kammerman, 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, 2020

Major Director: Cynthia Nau Cornelissen, Ph.D.

Professor, Department of Microbiology and Immunology

Neisseria gonorrhoeae, the bacterial agent that is responsible for the human disease gonorrhea, has had a steady increase in the number of infections per year. In 2018 the WHO estimated over 87 million infections occurred world-wide, and the CDC …

The Influence Of Breeding Density On Female Aggression, Parental Care, And Ornamentation In A Secondary-Cavity Nesting Warbler, Elsa B. Chen

Theses and Dissertations

Tradeoffs between individual survival and reproductive success associated with aggressive behaviors are a driving force of evolution, but these tradeoffs are often overlooked for aggressive conspecific interactions between females. For avian males, it is well documented that more aggressive individuals tend to provide less parental care. In the few studies that address this in females, the tradeoffs seem to be more context-dependent, varying due to factors such as predation pressure and habitat quality. The relationship between female ornamentation and aggression is similarly understudied, but evidence suggests that both aggression and ornamentation are important traits involved in social selection – the …

It’S Funny Because It’S True: The Transmission Of Explicit And Implicit Racism In Internet Memes, Tabitha Fairchild

Theses and Dissertations

Video games are traditionally seen as the domain of heteronormative white males. The purpose of this study is to explore how racism is transmitted and reproduced within digital communities, and how humor is being used to frame racist discourse in virtual spaces. Digitally, internet memes are widely used rhetorical vehicles, reaching large and broad audiences. The roles these artifacts play in the reproduction and transmission of racist ideology is often obfuscated by the perception that internet memes are "just jokes." This study analyzes internet memes collected from 16 months of communication between members of Discord servers that self-identify as communities …

Investigation Into The Reaction Profile Of A Bioinspired Nickel Complex, Denver Heitger

Theses and Dissertations

Metal complexes that can activate natural oxidants like H₂O₂ and O₂ have become a key research topic in many labs in hope of mimicking nature, by generating a bioinspired complex that can perform unique chemistry through green processes. To prepare the perfect catalyst, this has lead scientists to explore numerous avenues, including the use of both natural and artificial oxidants, to tease apart the reaction pathway taking place. A ligand system dear to the Lucas Lab (13-DOB) has been metalated with nickel, a cheap and earth abundant transition metal. Our bioinspired metal-(di)oxygen adducts can be formed …

The Quantified Elf, Umico Niwa

Theses and Dissertations

The Quantified Elf is an ongoing collection of scientific, medical, archaeological articles and excerpts from my personal journal. It is a way by which I explore the various ways Western notions of personhood subsume human life into constructs of sexuality and gender, overlooking the various other modes of unbridled existence: plant, microbial. fungal, animal, celestial bodies. The speculative medical papers propose novel forms of body modification to combat gender dysphoria.

Comparing Coastal Storm Impact To Decadal Change In Barrier Island Ecosystems, Philip A. Tuley

Theses and Dissertations

Highly dynamic coastal systems respond to disturbance events with a combination of topographic and vegetative changes. Sea level rise impacts on barrier islands have been quantified, but storm effects on vegetation are limited. Here we quantified barrier island vegetation change in response to an isolated storm event and compared to long-term periods. We hypothesized that disturbance-resisting areas with high woody vegetation cover and/or high foredune elevation would experience minimal transitions after a storm event, whereas disturbance-reinforcing areas with low vegetation cover and low foredune elevation would experience greater transitions between ecosystem states after a storm event. Patterns of dissonance were …

A Story About A Girl With Snakes For Hair, Kate M. Turner

Theses and Dissertations

My work is autobiographical. I use various art making processes to create a visual archive of my life. By abstracting these memories and experiences, I can examine how culture works surrounding issues of identity. This is my story.

The Impact Of Aging And Mechanical Injury On Alveolar Epithelial And Macrophage Responses In Acute Lung Injury And Inflammation, Michael S. Valentine

Theses and Dissertations

Patients with severe lung pathologies, such as Acute Respiratory Distress Syndrome (ARDS), often require mechanical ventilation as a clinical intervention; however, this procedure frequently exacerbates the original pulmonary issue and produces an exaggerated inflammatory response that potentially leads to sepsis, multisystem organ failure, and mortality. This acute lung injury (ALI) condition has been termed Ventilator-Induced Lung Injury (VILI). Alveolar overdistension, cyclic atelectasis, and biotrauma are the primary injury mechanisms in VILI that lead to the loss of alveolar barrier integrity and pulmonary inflammation. Stress and strains during mechanical ventilation are believed to initiate alveolar epithelial mechanotransduction signaling mechanisms that contribute …

Epigenetic Regulation Of Drug Metabolizing Enzymes In Normal Aging, Mohamad M. Kronfol

Theses and Dissertations

Geriatric populations are at a higher risk for adverse drug reactions (ADRs). This may be partly due to changes in drug metabolism in old age, but the underlying mechanisms are poorly understood. Prior research in humans and mice has shown age-associated changes to the expression of several genes involved in drug metabolism. Furthermore, studies of human blood showed that epigenetic regulation of genes encoding drug metabolizing enzymes change with age. However, it is unknown if genes in the liver are similarly affected. Therefore, we hypothesize that genes encoding drug metabolizing enzymes may show differential epigenetic regulation in the liver with …

Probing Vibrational Wave Packets In Organophoshorous Molecules Using Femtosecond Time-Resolved Mass Spectrometry (Ftrms), Derrick Ampadu Boateng

Theses and Dissertations

The study of organophosphorus and nitroaromatic compounds is essential due to their suitability as models for understanding the dynamics of radiation induce damage to DNA sugar-phosphate backbone, and the detection of chemical warfare agents as well as nitroaromatic explosives (such as TNT). The ultrafast dynamics of these polyatomic radicals were studied using femtosecond time-resolved mass spectrometry (FTRMS), a versatile method that is capable of monitoring the ultrafast dynamics of rapid dissociation in the gas phase after the removal of an electron. The method uses a technique called pump-probe, which makes use of two time-delayed laser pulses. In this work, the …