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Carbon Dioxide Dynamics In The Carbonate Critical Zone, Savoy Experimental Watershed, Arkansas, Usa, Michael Darvin Jones

Graduate Theses and Dissertations

The dynamics of carbon dioxide (CO₂) within the Earth’s critical zone (CZ) are essential for driving spatial and temporal variations of carbonate dissolution and precipitation, which are fundamental to subsurface porosity and permeability development. However, there is still a significant knowledge gap regarding the patterns of CO₂ transport and production within the carbonate critical zone (CCZ). In this study, we investigated these dynamics within a mantled karst terrain at the Savoy Experimental Watershed (SEW) in Northwest Arkansas.

Previous monitoring of partial pressure of CO₂ (PCO₂) and dissolution rates at karst springs in …

Understanding The Interactions Between Pollen-Borne Ilarviruses And Pollinators In Peach Orchards, Mandeep Tayal

All Dissertations

Pollen-mediated virus transmission is a common problem in fruit crops. Prunus necrotic ringspot virus (PNRSV) and prune dwarf virus (PDV) are pollen-borne ilarviruses endemic to the southeastern U.S. and cause substantial losses in peach production. PNRSV and PDV are primarily transmitted through vegetative propagation (grafting) as well as via pollen and seed. However, the role of pollinators in transmission dynamics of these viruses is not well understood. First, I documented the bee diversity and abundance during peach bloom in South Carolina, identifying Bombus and Apis as the most dominant genera, followed by Eucera, Andrena and Habropoda. Bee community composition …

Cross-Interactions Of Amyloid Proteins: Implications For Aggregation Dynamics And Disease Pathology, Zhiyuan Song

All Dissertations

Amyloid aggregation is a pervasive form of protein misfolding implicated in the pathology of several prominent human diseases, including Alzheimer’s disease (AD), Parkinson’s disease (PD), and type 2 diabetes (T2D). These diseases are marked by the accumulation of amyloid fibrils and toxic oligomers, which are highly dynamic and heterogeneous, posing challenges for understanding their roles in disease progression. Despite significant advances in the diagnosis and management of these conditions, no definitive cure is available. We investigate amyloid aggregation and cross-seeding, with a focus on amyloid-beta (Aβ), tau, alpha-synuclein (αS), and human islet amyloid polypeptide (IAPP) through discrete molecular dynamics (DMD) …

Alfred Russel Wallace Notes 33. The Story In Evolution., Charles H. Smith

Faculty/Staff Personal Papers

Alfred Russel Wallace (1823-1913) is best known for his independent formulation of the principle of natural selection. In this work I first review my understanding of Wallace’s intellectual development on this subject, including the notion that he had no model for the evolution of higher consciousness as of his first treatment of natural selection in 1858. This leads to some conclusions about his approach to the subject, and links to parallel ideas inherent in the philosophy of Baruch de Spinoza (1632-1677).

The New Anthropocentrism: The Problem Of Water Conservation And Water Justice, Benjamin Stuart Milam

Open Access Theses & Dissertations

My objective with my thesis is to argue for and reinforce a type of anthropocentrism that is both environmentally conscious and consumable for an audience that is not necessarily well versed in philosophical literature. In the first chapter I go over philosophical frameworks, such as Anthropocentrism and Biocentrism, and why I believe they do not meet both of those criteria listed. After that I discuss New Anthropocentrism, coined by Clive Hamilton, and why I believe that a slightly modified version possesses qualities that I believe are needed for the crisis at hand. In chapter 2 I use that framework and …

Uncovering The Light Network Load Performance Penalty Of The Network Link Outlier Factor (Nlof), Michelle Lara

Open Access Theses & Dissertations

This thesis evaluates the effectiveness of the Network Link Outlier Factor with Most Likely Link (NLOF: MLL) algorithm under varying network load conditions. Repeated simulation experiments using Mininet were conducted for four different network-wide load levels: 100 Mbps, 500 Mbps, 1 Gbps, and 5 Gbps. Using statistical inference, our experimental results indicate that NLOF: MLL is ineffective under light load conditions (i.e., 100Mbps load) due to the limited network flow data available for its learning process. This limitation highlights a key challenge in applying the algorithm to lightly loaded networks. A preliminary algorithm was proposed to address this light-load performance …

Environmental Change As A Driver Of The Evolution Of Migratory Behavior In Suboscine Birds, Emily Johns

Open Access Theses & Dissertations

Avian migration, particularly long-distance seasonal migratory movement, has long captured the attention of researchers and the public alike. However, the evolutionary origins of migratory behavior are poorly understood, in part due to limited understanding of the full range of migratory strategies including short-distance and intra-tropical movements. We examine the climatic drivers of migration across suboscine birds, a group of roughly 1,300 primarily Neotropical species with a complex array of migratory strategies. Our reconstructions of the evolutionary history of suboscine migration reveal that migratory behavior is labile and is lost approximately twice as often as it is gained. We find that …

Ultra-High Temperature Ceramics: Materials, Manufacturing, And Machine Development, Joseph Matthew Munoz

Open Access Theses & Dissertations

This research aimed to advance the 3D printing of ultra-high-temperature ceramic matrix composites (UHTCMCs) and develop a custom Direct Ink Writing (DIW) system with multimaterial and in-line mixing capabilities. The study first focused on creating ZrB₂–SiC composites reinforced with aligned silicon carbide fibers (SiCf) using paste extrusion. By formulating suspensions with a preceramic polymer (SMP-10), ZrB₂, and SiCf, the study assessed how fiber alignment influenced key properties such as thermal and electrical conductivity and mechanical strength. Green curing and pyrolysis transformed the printed parts into UHTCMCs, with results showing substantial improvements in thermal conductivity—nearly double that of non-aligned parts—and a …

Enhancement Of Zika Virus Infection By West Nile And Dengue Virus Antibody Positive Cord-Blood Samples From Mothers In El Paso-Texas, Jeanette Orbegozo

Open Access Theses & Dissertations

The recent Zika virus (ZIKV) outbreak and its association with microcephaly cases and other neurological syndromes are important public health concerns. A phenomenon known as antibody-dependent enhancement (ADE) involves preexisting flavivirus antibodies to a specific flavivirus that enhances the severity of a second infection with a different flavivirus. Since ZIKV is related to flaviviruses like West Nile virus (WNV) and dengue virus (DENV), prior exposure to these viruses could elicit cross-reactive antibodies that may enhance a subsequent ZIKV infection. Therefore, this study aimed to determine if WNV and DENV antibodies from cord blood enhanced ZIKV infection in vitro. Initially, a …

Functional Analysis Of The Zebrafish Orthologs Of Host Cell Factor 1 Gene, David Paz

Open Access Theses & Dissertations

Host Cell Factor C1 (HCFC1) is a transcriptional co-activator factor that regulates the expression of over 5000 different downstream target genes in human cells. Missense mutations in the HCFC1 gene cause methylmalonic acidemia homocysteinemia cblX type (cblX). cblX, a multiple congenital anomaly syndrome (MCA) characterized by abnormal brain development, craniofacial abnormalities, metabolic deficits, and intractable epilepsy. Published studies suggest that HCFC1 regulates neural precursor proliferation, number, and differentiation. However, these results were derived from studies that were performed with nonsense alleles or transient knockdown approaches. Although these results demonstrate the importance of HCFC1 in brain development, they do not replicate …

Unpacking Exclusion: A Narrative Literature Review And Discrete Analysis Of Preschool Suspension And Expulsion, Megan Pheterson

Open Access Theses & Dissertations

This thesis explores exclusionary disciplinary practices in preschool settings, where children from marginalized groups, particularly racial minorities and those with disabilities, face a higher risk of suspension and expulsion. This thesis provides a qualitative overview and interpretation of existing literature, pointing trends and gaps in research and highlighting four main themes: (1) Navigating the layers of exclusionary practices: From policy to practice; (2) Exclusionary practices: An adult decision with complex consequences; (3) Exclusive education: Who is left out and why in early childhood settings; and (4) Resistance as a tool for inclusion. Through a Disability Critical Race Theory framework, this …

“Don’T Bring Your Feminism Here!”: The African Hair Braiding Salon As A Rhetorically Charged Space For Feminist Activism, Efe Plange

Open Access Theses & Dissertations

This project extends scholarship on Black beauty and hair care spaces in the US as rhetorically charged for various forms of activism. It specifically explores the nature of work, conversations and feminist ways of being among a group of braiders working together in an African hair braiding salon to legitimize the African hair braiding salon as a site with unique contributions to this body of work. Grounded in Feminist Geo-criticism and Conversational Rhetoric, the study seeks to make contributions that are relevant to the field of Rhetoric and more specifically the sub-field of feminist rhetorics, African and non-Western feminist rhetorics, …

Novel Therapuetic Approaches For Chagas Disease, Juan Carlos Silva

Open Access Theses & Dissertations

Chagas disease (CD) is caused by the hemoflagellate protozoan Trypanosoma cruzi. This disease is considered one of the 20 neglected tropical diseases (NTD), and it is estimated that 6 to 8 million people worldwide are diagnosed with CD. In the United States, Chagas infection is not reported in all states; however, most reported CD cases are chronic infections. Chagas infection is characterized by two phases: an acute and a chronic phase. Until this present moment, no prophylactic or therapeutic human vaccine is available. However, in a recent study in a murine model, our group showed that the synthetic 20-merpeptide (DAENPGGEVFNDNKKGLSRV) …

Examining The Relationship Between Adverse Childhood Experiences, Coping Behaviors, And Metabolic Syndrome In Mexican-American Men, Paulina Torres

Open Access Theses & Dissertations

Background: The prevalence of metabolic syndrome (MetS) has been increasing in the US over recent years. Individuals who have experienced adverse childhood experiences (ACEs) and developed maladaptive coping strategies are at increased risk of developing MetS. Hispanic men might have an increased risk of developing MetS due to higher exposure to ACEs and increased use of maladaptive coping strategies.Purpose: To examine the relationship between ACEs, coping, and MetS among Mexican-American men. Methods: A secondary analysis of cross-sectional study of 100 adult men from El Paso, Texas in 2018-19. ACEs were examined using the 10-item ACE questionnaire. Coping was assessed through …

Mechanical Stability Of Body-Centered Cubic Iron At Earth's Core Pressure And Temperature Conditions Using A Molecular Graph Kernel Regression And Gaussian Process., Blaise Awola Ayirizia

Open Access Theses & Dissertations

We used machine learning to study nonmagnetic BCC iron in conditions similar to thosefound in the Earthâ??s core. Our model predicts the stability of BCC iron at high temperatures and pressures by analyzing a dataset from ab initio molecular dynamics simulations. The framework uses Gaussian process regression to make predictions by comparing the similarity between molecules. This comparison is made using the marginalized graph kernel. To use the marginalized graph kernel, the framework applies a spatial adjacency rule to convert molecules into graphs, where the vertices and edges are labeled by elements and interatomic distances, respectively. We can use this …

Seasonal Abundances Of Aedes Aegypti And Culex Quinquefasciatus In An Urban Community In The Texas/Mexico Border, Kevyn Amezcua

Open Access Theses & Dissertations

AAedes aegypti and Culex quinquefasciatus are two medically relevant species of mosquitoes that can transmit several arboviruses that affect human health. Ae. aegypti is a vector for viral diseases such as Dengue, Yellow Fever, Chikungunya, and Zika, while Cx. quinquefasciatus is a vector for West Nile and Saint Louis Encephalitis. Both species are mostly found in urban environments and are affected by several anthropogenic factors such as the presence of artificial containers and overall changes to the native landscape. Little research is done on the ecology of these two species in the Chihuahuan desert, which has some areas that are …

Functionalized Carbon Quantum Dots: A Promising Nanomaterial For Investigating Their Potential In Neurodegenerative Disease Treatment, Sherin M. El Morsy

Open Access Theses & Dissertations

Neurodegenerative diseases such as Parkinson's Disease (PD), Alzheimer's Disease (AD), and Huntington's Disease (HD) remain incurable, despite extensive research into therapeutic development. In the United States of America, the annual cost of PD and AD in terms of patient care and lost productivity is approximately $200 billion. Consequently, there is a critical and unaddressed need for the development of innovative drugs and drug delivery systems that can decelerate, stop, or ideally reverse neurodegenerative diseases. The dissertation presented here focuses on devising strategies to target PD through multiple mechanisms, including the inhibition of protein aggregation and the reduction of oxidative stress. …

Implementing The Methodology To Generate Diagnostic And Therapeutic Antibodies, Andrea Mariana Carlin

Open Access Theses & Dissertations

This research aimed to establish the methodology for developing monoclonal antibodies at The University of Texas at El Paso. Monoclonal antibodies are indispensable across multiple fields, including diagnostics, therapeutics, and biotechnology, yet there is a shortage of commercially available antibodies targeting specific proteins or possessing specialized characteristics. To address this gap, three models were selected: a peptide derived from the intracellular protein Schlafen 8 and two cell surface protein receptors: mouse vascular endothelial growth factor receptor 2 (VEGFR2) and human melanocortin receptor 4 (MC4R). These proteins present unique challenges in antibody generation, including issues of accessibility, expression, and specificity.

Throughout …

Evolutionary History Of A Specialized And Diverse Highland Snake Complex (Crotalus Willardi), Michael Joseph Buontempo

Open Access Theses & Dissertations

The Ridgenosed rattlesnake (Crotalus willardi) is a highly unique group of small rattlesnakes consisting of 5 subspecies that inhabit the high elevation pine oak woodlands of the Sierra Madre Occidental and the Madrean Archipelago. They remain one of the most understudied groups of rattlesnakes with little understanding of the relationships between the subspecies. I utilize genomic level genetic data collected using ddRAD-seq methodology on 60 individuals encompassing all 5 subspecies and the majority of the range. Utilizing co-ancestry analysis, Admixture, and Phylogenetic analyses (both maximum likelihood and Bayesian approaches) we uncovered seven separate genetic groups. Of these, three consisted of …

Environmental Impact Assessments (Eia): Analysis Of Transboundary Environmental Impact Assessments For The Development Of A Uniform Teia Model, Nicolas Chapa

Open Access Theses & Dissertations

This dissertation investigates the evolution, processes, and importance of Environmental Impact Assessments (EIAs), focusing on transboundary EIAs and the need for a uniform framework. Originating from the National Environmental Policy Act (NEPA) of 1969 in the U.S., EIAs have become globally adopted instruments for assessing and mitigating environmental impacts of development projects. This work reiterates historical milestones, strengths, and current limitations of EIAs. Research also included a review of environmental regulations from Mexico, such as the General Law on Ecological Equilibrium and Environmental Protection (LGEEPA). Through several case studies requiring the use of transboundary EIAs, where shared resources and concerns …

Redefining Approaches For Measuring Landscape Subsidence And Permafrost Degradation In Arctic Tundra Environments, Tabatha Lynn Fuson

Open Access Theses & Dissertations

As climate change accelerates in the Arctic, the degradation of permafrost is leading to significant landscape transformation in tundra landscapes. This dissertation investigates the multifaceted responses of permafrost systems to warming, focusing on the dynamics of surface elevation changes and active layer thickness (ALT) across the North Slope of Alaska. In this study, I explore the capacity of repeat Terrestrial Laser Scanning (TLS) technology for modeling tundra features and detecting surface subsidence, specifically how different climate and landscape conditions during scanning impact TLS model precision. We also compare TLS model precision estimates to TLS model accuracy by comparing elevation values …

Examination Of The Role Of Ovarian Hormones On Nicotine Withdrawal Severity In Females, Priscilla Giner

Open Access Theses & Dissertations

Women are more susceptible to the long-term consequences of chronic nicotine exposure, and clinical evidence has shown that abstinence from nicotine exposure produces a withdrawal syndrome that is intensified by estrogen (E2 in rats) and progesterone (PR) in females. The goal of this Masterâ??s thesis was to determine the mechanisms by which E2 and PR promote withdrawal from nicotine vapor inhalation in female rats. Prior work in male rodents has revealed that nicotine withdrawal is modulated in the medial habenula-interpeduncular nucleus (MHb-IPN) pathway. Our hypothesis is that females experience greater inhibition of the IPN via local interneurons that release the …

Advancements In Polymer Synthesis And Ceramic Additive Manufacturing For Energy Applications, Sofia Gabriela Gomez

Open Access Theses & Dissertations

The aim of this work was to create polymer and ceramic materials for integration into energy applications. The first part of this research was to fabricate polymer syntactic foams that exhibited high energy absorption capabilities. The fabrication of polymer syntactic foams was feasible through synthesizing hollow polysiloxane microspheres that were imbedded into a polydimethylsiloxane (PDMS) matrix. An array of characterization techniques was used to test the material and physical properties of the syntactic foams. The next step of this research was to fabricate a porous water emulsion foam ink for use in Direct-Ink-Write (DIW) additive manufacturing (AM) technologies. Unlike the …

General Purpose Gpu Benchmarks For Neural Networks, Jose Maria Granados

Open Access Theses & Dissertations

Neural networks are a field of computing experiencing a rise in popularity in recent years due to the utilization of graphics processing units as their computational centerpiece. The lack of neural network benchmarks for the open-source Nyuzi architecture, a developing general-purpose processor with graphical processing capabilities, is the focus of this thesis. This work aims to determine whether Nyuziâ??s performance counters and traceable events suffice for performance tuning of neural network implementations. Given the mathematical intensity of neural networks, a strong emphasis is placed on events related to arithmetic instructions. Experimenting with neural network implementations in C and C++, existent …

Preparing Educators To Effectively Engage With Postsecondary Stem Students With Autism, Luzconsuelo Gavaldon

Open Access Theses & Dissertations

Autism spectrum disorder (ASD) is a lifetime mental disability (Boucher, 2009). Because the brains of people with autism work differently than their non-neurodiverse peers (Kuzminskaite et al., 2020), they tend to respond to external stimuli in a hypo- or hyper-sensory fashion. One of the primary considerations that must be accounted for when working with individuals with autism is that the brains of these persons are each neurologically distinct. In other words, there is no "one-size-fits-all" means by which individuals with ASD learn and develop and, consequently, no single way to therefore engage with said individuals (Anderson & Butt, 2017; Kuzminski …

Heat Acclimated Algae Improves Heat Tolerance And Longevity In Daphnia, Ashit Dutta

Electronic Theses and Dissertations

Xenohormesis suggests that consuming stressed food provides physiological adaptation to the consumer for similar stresses. To evaluate this, Daphnia magna was provided with heat-stressed Nannochloropsis limnetica grown at 25℃ whereas the control group was provided Nannochloropsis limnetica grown at 12℃. In the heat tolerance experiment, Daphnia kept at 28℃ and 20℃ while consuming 25℃ algae had significantly higher heat tolerance compared to the control. Additionally, in stressed conditions, Daphnia consuming 25℃-grown food had significantly higher lifespan compared to the control. Next, Daphnia consuming 25℃-grown algae had significantly higher levels of antioxidants which could explain the lifespan extension. Finally, in fatty …

Electrochemical Biosensing Of Cerium With A Tyrosine-Functionalized Ef-Hand Loop Peptide, Sogol Asaei, Geeta Verma, Nicholas S. Sinclair, Julie N. Renner

Faculty Scholarship

The significance of easily detecting rare earth elements (REEs) has increased due to the growing demand for REEs. Addressing this need, we present an innovative electrochemical biosensor, focusing on cerium as a model REE. This biosensor utilizes a modified EF-hand loop peptide sequence, incorporating cysteine for covalent attachment to a gold working electrode and tyrosine as an electrochemically active amino acid. The sensor was designed such that binding to cerium induces a conformational change in the peptide, affecting tyrosine's proximity to the electrode surface, modulating the current. A calibration curve was generated from cyclic voltammetry current peaks at ~0.55–0.65 V …

Epanorama December 2024, Southern Adventist University

Panorama Parent Newsletter

This electronic issue of Panorama includes information on campus holiday events, enrollment information, and awards won during the Society of Adventist Communicators competition in Chicago in October.

You Look Nice, Lily Monnett

A Midwestern Review: A Magazine of the Arts and Issues at DePauw University

Lily Monnett is a Senior Environmental Biology major, English Writing minor, and Environmental Fellow at DePauw University. She is also a part of the DePauw Women’s Cross Country and Track teams.

Artificial Neurovascular Networks To Simulate Energy Distribution To Spiking Neural Networks, William Bottom

Theses

Biological neurons are known to be much more energy efficient than modern computers, with the human brain only consuming about 20 Watts. An Artificial Neural Network can take hours or days to train on high-performance and energy-consuming GPUs, so networks that can achieve similar performance at a fraction of the energy cost are very sought after. Spiking Neural Networks, which mimic biological neurons more closely than Artificial Neural Networks (ANNs), are a potential option for the energy problem in Neural Networks. By converting an ANN to an SNN and applying energy-saving methods/architectures, the equivalent SNN network can achieve similar performance …