Digital Commons Network^™

Influence Of Consumer Involvement In Tourist Information Search: Application Of Economics Of Information Theory In A Destination, Peter Judca Mkumbo

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In the modern digital world, it is increasingly challenging for destination marketers to design integrated marketing communication (IMC) strategies. The spectrum of information sources has become broader, serving for wider market interests. The importance of information in the modern world is increasing exponentially, and the tourism industry is traditionally information intense. There is an endless list of information outlets, and it is impossible to be present in all the information platforms. The spectrum of outlets includes old-school prints like magazines and newsletters on the one hand, while on the other hand there are modern advanced Web 2.0 technologies like social …

Experiences Of Upstate South Carolina Historical Preservationists: Wisdom For Cultivating Future Advocates, Steven Clay Pruitt

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Current literature has suggested that despite scholars in other fields gleaning vast amounts of experimental data to use to hone curriculum decisions and support their disciplines, researchers in social studies education have failed to look at Significant Life Experiences (SLEs) of Historical Preservationists (HPs) for the same benefit. The American Historical Association (AHA) cited a twenty-one percent dip in history majors since 2012 (Townsend, 2017), historic sites like Colonial Williamsburg have been hit by a lack of interest and visitation from the public (Tiedemann & Marsico, 2017), and many local historical associations and community museums have uncertain futures due to …

Modelling The Effects Of Disease-Associated Single Amino Acid Variants And Rescuing The Effects By Small Molecules, Yunhui Peng

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Single nucleotide polymorphism (SNP) is a variation of a single nucleotide in the genome. Some of these variations can cause a change of single amino acid in the corresponding protein, resulting in single amino acid variation (SAV). SAVs can lead to profound alterations of the corresponding biological processes and thus can be associated with many human diseases. This dissertation focuses on integration of existing and development of new computational approaches to model the effects of SAVs with the goal to reveal molecular mechanism of human diseases. Since proton transfer and pKa shifts are frequently attributed to disease causality, the proton …

High-Throughput Polygenic Biomarker Discovery Using Condition-Specific Gene Coexpression Networks, William Louis Poehlman

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Biomarkers can be described as molecular signatures that are associated with a trait or disease. RNA expression data facilitates discovery of biomarkers underlying complex phenotypes because it can capture dynamic biochemical processes that are regulated in tissue-specific and time-specific manners. Gene Coexpression Network (GCN) analysis is a method that utilizes RNA expression data to identify binary gene relationships across experimental conditions. Using a novel GCN construction algorithm, Knowledge Independent Network Construction (KINC), I provide evidence for novel polygenic biomarkers in both plant and animal use cases.

Kidney cancer is comprised of several distinct subtypes that demonstrate unique histological and molecular …

Investigating The Use Of Streaming And Robotic Dielectrophoresis To Enable Continuous Cell Sorting And Automatic Cell Transfer In Sample Preparation, Rucha Natu

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The sorting of targeted cells or particles from a sample is a crucial step in the sample preparation process used in medical diagnosis, environmental monitoring, bio-analysis and personalized medicine. Current cell sorting techniques can be broadly classified as label based or label-free. Label-based techniques mostly rely on fluorophores or magnetic nanoparticles functionalized to bind with targeted cells. Although highly specific, this approach can be expensive and suffers from limitations in the availability of suitable markers. Label-free techniques exploit properties inherent to the cell, such as density and size, to simplify the sorting protocol and reduce cost by eliminating the need …

Taxonomic, Genetic And Functional Diversity Of Symbionts Associated With The Coastal Bivalve Family Lucinidae, Jean S. Lim

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Extant bivalve members from the family Lucinidae harbor chemosynthetic gammaproteobacterial gill endosymbionts capable of thioautotrophy. These endosymbionts are environmentally acquired and belong to a paraphyletic group distantly related to other marine chemosymbionts. In coastal habitats, lucinid chemosymbionts participate in facilitative interactions with their hosts and surrounding seagrass habitat that results in symbiotic sulfide detoxification, oxygen release from seagrass roots, carbon fixation, and/or symbiotic nitrogen fixation. Currently, the structural and functional complexity of whole lucinid gill microbiomes, as well as their interactions with lucinid bivalves and their surrounding environment, have not been comprehensively characterized. This dissertation focuses on the taxonomic, genetic, …

Fabrication And Mechanical Properties Of Micro-Architectured 3d Scaffolds, Pooya Niksiar

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Freeze casting is a physical process for the fabrication of porous anisotropic materials. In this method, an aqueous slurry of ceramic particles is frozen directionally, creating lamellar columns of ice that push particles between the growing crystals. Then, the frozen material is lyophilized to remove the ice and sintered to densify the ceramic. Scaffolds made by freeze casting often have significant strength in the solidification direction, while they lack sufficient strength in the transverse direction. To enhance strength in the transverse direction, magnetite particles are added to a slurry of paramagnetic particles, and an external magnetic field is applied during …

Chemically Active Rheological Modifiers For The Improved Clinical Use Of Cyanoacrylates, Kyle Joseph Garcia

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Over 100 million surgical incisions, 50 million traumatic wounds, and 20 million minor lacerations from cuts and grazes are treated globally each year. One study determined that globally internal and external wounds occur for 40% and 37% of cases respectively for a total of 111 million patients that were treated for wounds. The remaining 23% of patients were treated for minor lacerations and trauma in the emergency room. These wounds require immediate medical attention including pressure application, sutures, clips, tissue cautery, and/or topical hemostatic agents to cease hemorrhage or the exit of other bodily fluids. With blood flow ceased, wound …

Computational Approaches To Understanding Structure-Function Relationships At The Intersection Of Cellular Organization, Mechanics, And Electrophysiology, Tyler George Harvey

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The heart is a complex mechanical and electrical environment and small changes at the cellular and subcellular scale can have profound impacts at the tissue, organ, and organ system levels. The goal of this research is to better understand structure-function relationships at these cellular and subcellular levels of the cardiac environment. This improved understanding may prove increasingly important as medicine begins shifting toward engineered replacement tissues and organs. Specifically, we work towards this goal by presenting a framework to automatically create finite element models of cells based on optical images. This framework can be customized to model the effects of …

Additive Manufacturing Of Ceramics With Multiscale Heterogeneous Microstructure, Yuzhe Hong

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The additive manufacturing (AM) of ceramic has gained significant attentions because of the difficulties in fabricating hard and brittle ceramics into complex geometry. In addition, AM provides the possibility of fabricating ceramic parts with heterogeneous microstructure on the multiscale, which cannot be achieved using the traditional methods. In today’s AM technologies, ceramics are often extruded for form a green body and then fired to a high density. However, two challenges are faced by the extrusion-based AM of ceramics with multiscale features. One is to depositing ceramics with submicrometer thickness. The other one is to embed microchannels in large-scale ceramic parts. …

High-Achieving, Non-First-Generation, Female, Undergraduate Student Views Of Family Influence On Career Decisions, Katryna Bower Maxwell

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This qualitative study sought to understand how high-achieving, non-first-generation, female, undergraduate students viewed the influence parents and families had on their career decisions. This study’s six participants were students in the same honors college at a large, four-year, public university in the Southeast United States. Data from a pre-interview survey, initial interview, in-depth interview, and interview observation protocols were used to understand participants’ career decision-making processes and the influence their parents and families had on those processes. Thematic coding was used to identify three common themes found among participants: (a) parent and family support (b) family influence on career decision-making …

Cases Of Contingent Stem Faculty Who Practice Critical Pedagogies With/In The Neoliberal University, Jeffrey Michael Kenney

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An increasingly neoliberal university means diminishing resources and labor security for those located in the lowest echelon, particularly those engaged in critical/radical/activist projects. The purpose of this study was to generate knowledge in an effort to sustain and advance critical pedagogical practices in college teaching. This study focused principally on the knowledge and insights of contingent STEM faculty who practice critical pedagogies in the neoliberal conditions of public universities. Utilizing critical and pragmatic perspectives, I explored both the ingenuity and practicality of the participants’ praxis as well as examined the structural machinations of neoliberal capitalism within their teaching and learning …

Improving Deep Reinforcement Learning Using Graph Convolution And Visual Domain Transfer, Sufeng Niu

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Recent developments in Deep Reinforcement Learning (DRL) have shown tremendous progress in robotics control, Atari games, board games such as Go, etc. However, model free DRL still has limited use cases due to its poor sampling efficiency and generalization on a variety of tasks. In this thesis, two particular drawbacks of DRL are investigated: 1) the poor generalization abilities of model free DRL. More specifically, how to generalize an agent's policy to unseen environments and generalize to task performance on different data representations (e.g. image based or graph based) 2) The reality gap issue in DRL. That is, how to …

Forestry And Arboriculture Applications Using High-Resolution Imagery From Unmanned Aerial Vehicles (Uav), Brian A. Ritter

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Forests cover over one-third of the planet and provide unmeasurable benefits to the ecosystem. Forest managers have collected and processed countless amounts of data for use in studying, planning, and management of these forests. Data collection has evolved from completely manual operations to the incorporation of technology that has increased the efficiency of data collection and decreased overall costs. Many technological advances have been made that can be incorporated into natural resources disciplines. Laser measuring devices, handheld data collectors and more recently, unmanned aerial vehicles, are just a few items that are playing a major role in the way data …

Impacts Of Thermal Barrier Coating Morphology And Catalytic Properties On Low Temperature Combustion Engine In-Cylinder Processes, Thomas Powell

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The inherent thermodynamic benefits of Homogeneous Charge Compression Ignition (HCCI) make it a likely choice for meeting the increasing demands of fuel economy legislation. Unfortunately HCCI suffers from reduced combustion efficiency and operational variability due to the buildup of carbon deposits. However, the unique thermo-kinetic nature and thermal sensitivity of Low Temperature Combustion (LTC) provides an opportunity to improve combustion efficiency through manipulation of the in-cylinder thermal environment. This body of work sought to create a wall temperature swing using a thin Thermal Barrier Coating (TBC) to reduce combustion heat transfer and improve LTC combustion and thermal efficiencies. The first …

N-Alkyl Methacrylate Polymeric Memristors For Synaptic Response Modeling: Organic And Biologically Relevant Thin Films, Tucker Mcfarlane

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There is a strong interest in organic materials for electrical devices due to several advantages that organic systems have over their inorganic counterparts including ease of processability and lower toxicity. Many of these organic materials can be utilized in the creation of thin-film devices that can be formed in high-throughput processes and with a very small profile. One such device that has emerged in recent years is the memristor which can be used in new computational concept or as a synaptic model. This work studies the alternating current (AC) and direct current (DC) electrical response of a number n-alkyl methacrylate …

Subventricular Zone Neural Stem Cells Release Extracellular Vesicles During Early Postnatal Neurogenesis, Mary C. Morton

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Extracellular vesicles (EVs) are nanometer sized particles released from all cells. EVs are found in all biological fluids, including cerebrospinal fluid (CSF) and blood. EVs modulate intercellular communication through the transfer of nucleic acids and proteins from donor to recipient cells. During early postnatal neurogenesis, subventricular zone (SVZ) neural stem cells (NSCs) asymmetrically divide to give rise to neuroblasts that migrate along the rostral migratory stream (RMS) and populate the olfactory bulb (OB). Other, non-neuronal cells populate the SVZ, such as microglia and endothelial cells. Microglia have been shown to regulate SVZ NSCs, but it remains unclear if this communication …

Research Exemplars From An Interdisciplinary Healthcare Genetics Program, Rebecca Leigh Myers

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The first chapter of this dissertation provides an overview of the interdisciplinary Healthcare Genetics model, the framework for the studies described in Chapters Two, Three and Four. The model is comprised of five core constructs: Research, Environment, Clinical Practice, Ethical/Legal/Social Implications (ELSI) and Education. Each construct is defined. Chapter One also presents a brief overview of subsequent chapters.

Chapter Two details a biophysical approach to the phenotypic classification of mutations in the 7-dehydroxycholesterol reductase (DHCR7) gene, involved in Smith-Lemli-Opitz syndrome. This study utilized computer modeling to determine the biophysical effects of each mutation on structure and function of the DHCR7 …

Analysis Of Frozen Desserts Using Low-Temperature Scanning Electron Microscopy (Lt-Sem), Kinsey Elizabeth Macdonald

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Commercial vanilla ice cream and other frozen desserts from the United States were analyzed for ice crystal length using low-temperature scanning electron microscopy (LT-SEM). Average ice crystal length was determined using multiple micrographs of each sample/product. Out of the products tested, 11 out of 15 samples had an average ice crystal length above the consumer sensory threshold limit of 55 µm. Products containing stabilizers tended to have smaller average ice crystal lengths than products without stabilizers. With a few exceptions, lower fat products tended to have larger ice crystals because there was less fat to stabilize the ice crystals. Four …

Towards Automated Verification Of Object-Based Software With Reference Behavior, Yu-Shan Sun

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Automated verification is critical for ensuring that an implementation is correct and meets the specified behavior on every valid input. Verification should be modular to promote reuse and to scale up. However, for code that involves explicit reference behavior, there is the added complexity of reasoning that only the intended objects are being affected. This research focuses on simplifying automated verification and enabling modular verification using data abstractions that hide explicit reference behavior. While avoiding explicit reference behavior simplifies reasoning for a majority of software components, for capturing unavoidable reference behavior, such as that needed to implement classes of lower-level …

Vulnerability Of Tri-Colored Bats (Perimyotis Subflavus) To White-Nose Syndrome In The Southeastern United States, Pallavi Sirajuddin

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Tri-colored bats (Perimyotis subflavus) have experienced significant population declines in the southeastern United States due to white-nose syndrome (WNS). The lack of information on the torpor patterns and winter activity in conjunction with the rapid decline from the disease has led to an increased effort in researching the hibernation physiology and wintering activity of P. subflavus and their response to WNS in southern hibernacula. To address this growing concern, we used temperature sensitive radio transmitters to examine torpor patterns in three geographically distinct states and acoustic detectors to monitor bat activity within a WNS-positive hibernaculum. Our specific objectives …

Developing Optimization System For Improving Highway Network Performance Under Seismic Hazards: A Case Study Of Charleston, Sc, Nixon Wonoto

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A significant number of bridges in the Central and Southeastern United States (CSUS) are known to have a design that is lacking or no seismic consideration. In an article by Wong et al., Charleston is considered an active seismic zone, and the economic loss from the Charleston region could reach over $14 billion if 1886 Charleston’s earthquake would happen again in the near future. Due to lack of present consideration in seismic design for bridges in CSUS, there has been emerging research that studies retrofit strategies for CSUS region such as in Charleston. However, most of the retrofit program, including …

Building A Model Of Black Women's Confidence In Campus Sexual Assault Resources: A Critical Race Feminist Quantitative Study, Jimmy Lee Howard, Jr.

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The United States’ evolving federal regulations and laws are doing little to disrupt systemic sexual violence, and more narrowly, are doing very little to protect Black women (Dunn, 2014; Harris, 2017; Harris & Linder, 2017; Konradi, 2016; O’Toole et al., 2015; Yung, 2015). Further, Black women are underrepresented in college sexual assault literature and little is known about how Black women perceive campus sexual violence resources and policy (Crosby, 2015; Tillman et al., 2010). The purpose of this study is to create a model to explore Black women’s confidence in sexual assault resources. In order for institutions of higher education …

Exploring Dynamics And Performance Of International Education (Ie) And Senior International Officer (Sio) Through A Lens Of Complexity And Network Theories, Po Hu

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The purpose of this study is to explore the nature of complex adaptive systems (CAS) and network dynamics in international education (IE) programs in a U.S. higher education institution. I analyze the IE programs through a lens of complexity and network theories and ask how measures of engagement in complex networks affect performance in the IE system. This study presumes that today's international education programs in the U.S. higher education institutions are complex adaptive systems and that traditional leadership is no longer adequate to address the overwhelming opportunities and challenges posed by global education. A two-stage quantitative research design is …

Building Thermally Stable Electrochemical Energy Storage Devices Via Application Of Temperature Responsive Polymers, Han Jiang

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Electrochemical energy storage devices such as supercapacitors (SCs) and lithium ion batteries (LIBs) play pivotal role in the undergoing “green energy revolution”, which involves the profound transformation of energy production pattern from fossil fuel to renewable energy such as solar and wind due to environmental pollution, global warming, and the inevitable depletion of crude oil and coal. However, wide applications of SCs and LIBs are still limited due to issues like thermal runway and derived hazards such as ageing or capacity degradation, fires and explosions. Even more so, thermal control issues only aggravate in large format devices. With the purpose …

Carbon Fibers With Enhanced Mechanical Properties Derived From Lignin-Based Precursors, Jing Jin

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Carbon fibers are known for their outstanding specific strength and modulus, and they have been commercially used in structural and lightweight composites. However, the main barriers to the large-scale commercial application of carbon fibers are the high cost of petroleum-based precursor polyacrylonitrile (PAN) and the environmental concerns associated with its conversion to carbon fibers. Toxic by-products such as hydrogen cyanide (HCN) are generated during the stabilization step of PAN-based carbon fibers. Other precursors being used today, carbonaceous pitch and rayon, either are too expensive or produce carbon fibers with low strength. Among bio-derived feedstocks, lignin is of increasing interest as …

Augmenting A Hazard Analysis Method With Error Propagation Information For Safety-Critical Systems, Fryad Khalid M. Rashid

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Safety-critical systems need specific activities in the software development life cycle to ensure that the system will operate safely. The objective of this dissertation is to develop a new safety analysis method to identify hazards. The method uses error propagation information and the internal structure rather than the interfaces of a system. We propose development procedures to augment STPA (System-Theoretic Process Analysis) with error propagation information derived from the architecture description of a system represented in the AADL (Architecture Analysis Design Language). We will focus on how the AADL error ontology can be used to assist in identifying errors, how …

The Effects Of Various Retort Motions On The Rate Of Heat Penetration Of A Food Simulant In Pouches, Mollye Macnaughton

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Processing foods in a retort is a reliable and established method of creating sterile and shelf stable products. The formula of the product and the package size dictates the processing time. Rotary retorts were invented to agitate cans to reduce the processing times and create uniform heating within the can. Recently, horizontal reciprocating agitation has become a feature of retorts referred to as Gentle Motion® and Shaka®. Oscillating agitation is an even newer possible retort motion. This research experiment was designed to (1) determine the effects of oscillating continuously and oscillating-dwell time on the rate of heat penetration in a …

Tunneling Transport Phenomena In Topological Systems, Christopher Moore

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Originally proposed in high energy physics as particles, which are their own anti-particles, Majorana fermions have never been observed in experiments. However, possible signatures of their condensed matter analog, zero energy, charge neutral, quasiparticle excitations, known as Majorana zero modes (MZMs), are beginning to emerge in experimental data. The primary method of engineering topological superconductors capable of supporting MZMs is through proximity-coupled semiconductor nanowires with strong Rashba spin-orbit coupling and an applied magnetic field. Recent tunneling transport experiments involving these materials, known as semiconductor-superconductor heterostructures, were capable for the first time of measuring quantized zero bias conductance plateaus, which are …

The Effects Of Embryonic Arsenic Exposure On Muscle And Olfactory Development In Killifish (Fundulus Heteroclitus), Dana Bethany Szymkowicz

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Arsenic is an environmental contaminant that is commonly found in drinking water, rice, and other food sources around the world. Many epidemiological studies have reported that in utero exposures to arsenic can significantly reduce muscle growth and cause neurodevelopmental abnormalities such as reduced IQ, impaired memory and spatial learning, and sensory functions. However, the mechanisms behind such effects are not well known. Because of this, we wanted to explore the potential mechanisms by which embryonic exposure to environmentally-relevant levels of arsenic are not only impairing growth but also inducing behavioral changes due to altered sensory neuron function. We were also …