Physical Sciences and Mathematics Commons^™

Implications Of Metal Coordination In Damage And Recognition Of Nucleic Acids And Lipid Bilayers, Ana Dreab

Chemistry & Biochemistry Theses & Dissertations

Metal ions have a myriad of biological functions from structural stability to enzymatic (de)activation and metabolic electron transfer. Redox-active metals also mediate the formation of reactive oxygen species which may either cause oxidative damage or protect cellular components. Computational modeling is used here to investigate the role of (1) metal-ion binding to antimicrobial peptides, (2) metal-ion removal and disulfide formation on zinc finger (ZF) proteins, and (3) coordination of thiones/selones for the prevention of metal-mediated redox damage.

Piscidins, natural-occurring antimicrobial peptides, efficiently kill bacteria by targeting their membranes. Their efficacy is enhanced in vitro by metal-binding and the presence of …

Data-Driven Framework For Understanding & Modeling Ride-Sourcing Transportation Systems, Bishoy Kelleny

Civil & Environmental Engineering Theses & Dissertations

Ride-sourcing transportation services offered by transportation network companies (TNCs) like Uber and Lyft are disrupting the transportation landscape. The growing demand on these services, along with their potential short and long-term impacts on the environment, society, and infrastructure emphasize the need to further understand the ride-sourcing system. There were no sufficient data to fully understand the system and integrate it within regional multimodal transportation frameworks. This can be attributed to commercial and competition reasons, given the technology-enabled and innovative nature of the system. Recently, in 2019, the City of Chicago the released an extensive and complete ride-sourcing trip-level data for …

Machicomoco State Park Shoreline Management Plan, Cameron W. Green, Donna A. Milligan, C. Scott Hardaway Jr., Christine A. Wilcox

Reports

Machicomoco State Park (MSP) is located along the York River in Gloucester County, Virginia, between Cedarbush Creek and Timberneck Creek. Figures are shown in Appendix A. Archaeological evidence dating to the Middle and Late Woodland Periods (200 BCE – 1000 CE) strongly suggests that the area is associated with Tsenacommacah and the Powhatan’s chiefdom (DCR, 2021).

The site was primarily used as a base for hunting, fishing, and oystering activities. The area was later settled by English colonists around 1639, and was eventually sold to John Catlett in 1792, where it remained in the Catlett family’s possession for over 200 …

Nitrogen Doping Of Electrochemically Activate Carbon Screen-Printed Electrodes, Ethan Galloway

Undergraduate Honors Theses

Screen printed electrodes (SPEs), which are prepared by patterning conductive inks or pastes onto an insulating support (e.g., plastic film), are widely employed as sensing and biosensing platforms due to their ease of fabrication and relatively low cost. This is especially applicable to electrodes of this nature prepared with carbon-based inks (SPCEs). To date, the most successful and significant commercial application of SPEs has been as test strips for glucose meters. Despite the maturity of this technology, SPE research remains very active as improvements in sensitivity and selectivity, which often involve modifying the electrode surface, hold the key to advancing …

Extraction And Partial Purification Of An Antibiotic-Like Compound From The Soil Bacterium Rhodococcus Strain Kchxc3, Elizabeth Bond

Undergraduate Honors Theses

Rhodococcus bacteria have many secondary metabolic pathways that may produce novel natural products. The bacterium Rhodococcus strain KCHXC3 was isolated from a soil sample collected near Kingsport, Tennessee and was found to produce an inhibitory compound active against a broad array of bacterial species, including the Gram negative pathogen Shigella sonnei. The aim of this research is to extract and purify the compound for future structure elucidation. A mixture of compounds from 3 month old agar plates inoculated with strain KCHXC3 was extracted using ethyl acetate. The crude extract was then partially purified utilizing a Sephadex LH-20 column, followed …

Pliocene Wood From The Gray Fossil Site, Owen Madsen

Undergraduate Honors Theses

The Gray Fossil Site in northeastern Tennessee preserves materials from a 5-million-year-old ecosystem, including wood from nearby trees. This study consists of three parts: conservation of wood remains, identification of taxonomic groups represented by the fossil wood, and measuring the organic content of fossil wood from the Gray Fossil Site. When excavated, wood specimens from the site are saturated due to a high local water table. After testing seven different techniques to dry wood specimens, wrapping a specimen in string and allowing it to dry slowly was the method least likely to cause warping and cracking. Microscopic examination of wood …

Simulating Polistes Dominulus Nest-Building Heuristics With Deterministic And Markovian Properties, Benjamin Pottinger

Undergraduate Honors Theses

European Paper Wasps (Polistes dominula) are social insects that build round, symmetrical nests. Current models indicate that these wasps develop colonies by following simple heuristics based on nest stimuli. Computer simulations can model wasp behavior to imitate natural nest building. This research investigated various building heuristics through a novel Markov-based simulation. The simulation used a hexagonal grid to build cells based on the building rule supplied to the agent. Nest data was compared with natural data and through visual inspection. Larger nests were found to be less compact for the rules simulated.

Stumbling Into Virtual Worlds. How Resolution Affects Users’ Immersion In Virtual Reality And Implications For Virtual Reality In Therapeutic Applications, Brianna Martinson

Undergraduate Honors Theses

Studies of how users experience Virtual Reality (VR) have thus far failed to address the extent to which rendering resolution and rendering frame rate affect users’ sense of immersion in VR, including applications of VR involving simulators, treatments for psychological and mental disorders, explorations of new and nonexistent structures, and ways to better understand the human body in medical applications.

This study investigated if rendering resolution affected users’ sense of immersion in VR. This was conducted by comparing the responses of two groups, relative to two measures of participant immersion: (a) participant’s sense of presence and (b) participant’s sense of …

Intraday Algorithmic Trading Using Momentum And Long Short-Term Memory Network Strategies, Andrew R. Whitinger Ii

Undergraduate Honors Theses

Intraday stock trading is an infamously difficult and risky strategy. Momentum and reversal strategies and long short-term memory (LSTM) neural networks have been shown to be effective for selecting stocks to buy and sell over time periods of multiple days. To explore whether these strategies can be effective for intraday trading, their implementations were simulated using intraday price data for stocks in the S&P 500 index, collected at 1-second intervals between February 11, 2021 and March 9, 2021 inclusive. The study tested 160 variations of momentum and reversal strategies for profitability in long, short, and market-neutral portfolios, totaling 480 portfolios. …

Artificial Intelligence And Deep Reinforcement Learning Stock Market Predictions, Andrew W. Brim

All Graduate Theses and Dissertations, Spring 1920 to Summer 2023

Billions of dollars are traded automatically in the stock market every day, including algorithms that use artificial intelligence (AI) techniques, but there are still questions regarding how AI trades successfully. The black box nature of these AI techniques, namely neural networks, gives pause to entrusting it with valuable trading funds. This dissertation applies AI techniques to stock market trading strategies, but it also provides exploratory research into how these techniques predict the stock market successfully.

This dissertation presents the work of three research papers. The first paper presented in this dissertation applies a artificial intelligence technique, reinforcement learning, to candlestick …

A Multi-Scalar Socio-Policy Analysis Of Resource Reallocation And Water Security In Twenty-First Century Utah, Usa, Clint P. Carney

All Graduate Theses and Dissertations, Spring 1920 to Summer 2023

As drought and a warming climate continue to impact the western United States, balancing the water needs of cities, agriculture, and natural systems is becoming increasingly more complex. One approach commonly promoted to address water supply issues is the transfer of water between users via markets. However, markets for water face multiple obstacles that can often be costly for participants due to constraints inherent in western U.S. water law. Coinciding with issues of cost, water markets must overcome disinterest among water rights holders in releasing their water rights for uses even if temporarily. Moreover, water transfers bring to light the …

Design Of Polymeric Membranes For Large-Scale Energy Storage, Michelle L. Lehmann

Doctoral Dissertations

Many countries have enacted renewable energy targets of 32% or more by 2040 to reduce their carbon footprint. However, due to the intermittent nature of renewable energy sources, long-duration energy storage systems are vital for providing a secure electricity supply. To meet this demand, new battery technologies utilizing earth-abundant and low-cost components are necessary. Among them, non-aqueous redox flow batteries represent a transformative energy storage system due to their flexible material selection and wide operating voltage window. A membrane plays a critical role in these next-generation energy storage technologies as it separates the anode and cathode while allowing for facile …

Optimization And Development Of Sodium-Based Electrolytes For Energy Storage Devices, Jameson L. Tyler

Doctoral Dissertations

Energy storage devices have undergone development for decades. Much of the research is focused on the improvement of energy density by developing existing electrodes and investigating novel electrode materials. This has led to the overall improvement of traditional lithium-ion batteries, but also the discovery of new energy storage devices such sodium-ion batteries, redox flow batteries, solid electrolyte-based batteries, and many more. As the field expands, fundamental research is necessary to fully ascertain the validity of these novel systems for long term success. One of the most important components to all electrochemical energy storage devices such as batteries and supercapacitors is …

Influence Of Tethered, Axially Coordinated Ligands On Rh(Ii,Ii)-Catalyzed Carbene Transfer Reactions, Cristian E. Zavala

Doctoral Dissertations

Dirhodium (II,II) paddlewheel complexes have become ubiquitous in diazo-mediated carbene transfer reactions. The Rh(II,II)-carbene intermediate is capable of a large variety of transformations such as cyclopropanation, C-H and X-H (O, N, S, Si, B) insertion reactions, cyclopropenations, and ylide transformations. Cyclopropanation reactions resulting in the formation of functionalized cyclopropane structures has always been a major focus in Rh(II,II)-carbene chemistry. Improvements on catalytic performance in cyclopropanations has largely focused on the modification of the bridging ligands and has resulted in Rh(II,II) catalysts that exhibit high reactivity and selectivity in cyclopropanation reactions. However, high enantio- and diastereoselectivity is not easily achieved with …

Slope Conjecture And Normal Surface Theory, Helene Swanepoel

<strong> Theses and Dissertations </strong>

In this thesis we explore the relationship between quantum link invariants and the geometric and topological properties for a family of pretzel knots P(−2r, 2r + 1, 2r + s), r ≥ 1 and s ≥ 3, as predicted by the Slope conjecture. This conjecture asserts a connection between the degree of the colored Jones polynomial and boundary slopes of these knots. We introduce fundamentals of knot theory and prove that the minimum degree of the Jones polynomial for the family of pretzel knots P(−2r, 2r + 1, 2r + s), r ≥ 1 and s ≥ 3, is −6r …

Coastal Sediment Response To The Diel Oxygen Cycle, Kara Gadeken

<strong> Theses and Dissertations </strong>

Shallow coastal sediments are sites of intense respiration and organic matter breakdown. Macroinfauna bioturbate and bioirrigate sediments which supplies microbes with oxygen and newly deposited organic material from surface sediments, facilitating microbial remineralization of organic matter. These processes depend heavily on the concentration of dissolved oxygen in overlying water. Shallow water oxygen patterns often follow a diel cycle as dissolved oxygen decreases at night due to respiration and then increases during the day with photosynthesis, creating recurring suboxic conditions that are potentially stressful to organisms. Sediment oxygen flux is known to depend on ambient dissolved oxygen concentration, but behavioral responses …

Characterization Of Water Flow And Solute Transport Driven By Preferential Flow In Soil Vadose Zone, Abdullah Al Mamun

All Dissertations

The vadose zone acts as a buffer zone between the ground surface and the aquifers underneath and controls the transmission of infiltrating water and contaminants, for example, pesticides and chemical spills. Therefore, understanding the flow and transport processes that dominate the vadose zone is important. Macropores are ubiquitous and particularly found in abundance in the vadose zone. These macropores facilitate preferential flow, through which water travels rapidly deep into the soil, bypassing most of the porous matrix. Preferential flow and transport have environmental significance as their processes impact hydrology, ecology, agriculture, subsurface contamination, and waste management sectors. Thus, the overall …

The Dense Gas Mass Fraction And The Relationship To Star Formation In M51, Mark Heyer, Benjamin Gregg, Daniela Calzetti, Bruce G. Elmegreen, Robert Kennicutt, Angela Adamo, Aaron S. Evans, Kathryn Grasha, James D. Lowenthal, Gopal Narayanan, Daniel Rosa-Gonzalez, F. P. Schloerb, Kamal Souccar, Yuping Tang, Peter Teuben, Olga Vega, William F. Wall, Min S. Yun

Astronomy: Faculty Publications

Observations of 12CO J = 1 - 0 and HCN J = 1 - 0 emission from NGC 5194 (M51) made with the 50 m Large Millimeter Telescope and the SEQUOIA focal plane array are presented. Using the HCN-to-CO ratio, we examine the dense gas mass fraction over a range of environmental conditions within the galaxy. Within the disk, the dense gas mass fraction varies along the spiral arms but the average value over all spiral arms is comparable to the mean value of interarm regions. We suggest that the near-constant dense gas mass fraction throughout the disk arises from …

Porous Silicon Photonics For Label-Free Interferometric Biosensing And Flat Optics, Tahmid Hassan Talukdar

All Dissertations

This dissertation uses porous silicon as a material platform to explore novel optical effects in three domains: (i) It studies dispersion engineering in integrated waveguides to achieve high performance group index sensing. With proper design parameters, the sensor waveguides can theoretically achieve 6 times larger group index shift compared to the actual bulk effective refractive index shift. We demonstrate the guided mode confinement factor to be a key parameter in design and implementation of these waveguides. (ii) It explores multicolor laser illumination to experimentally demonstrate perceptually enhanced colorimetric sensing, overcoming the limitations faced by many contemporary colorimetric sensors. Our technique …

Advancements In Gaussian Process Learning For Uncertainty Quantification, John C. Nicholson

All Dissertations

Gaussian processes are among the most useful tools in modeling continuous processes in machine learning and statistics. The research presented provides advancements in uncertainty quantification using Gaussian processes from two distinct perspectives. The first provides a more fundamental means of constructing Gaussian processes which take on arbitrary linear operator constraints in much more general framework than its predecessors, and the other from the perspective of calibration of state-aware parameters in computer models. If the value of a process is known at a finite collection of points, one may use Gaussian processes to construct a surface which interpolates these values to …

Designing And Evaluating Accessible E-Learning For Students With Visual Impairments In K-12 Computing Education, Earl W. Huff Jr

All Dissertations

This dissertation explores the pathways for making K-12 computing education more accessible for blind or visually impaired (BVI) learners. As computer science (CS) expands into K-12 education, more concerted efforts are required to ensure all students have equitable access to opportunities to pursue a career in computing. To determine their viability with BVI learners, I conducted three studies to assess current accessibility in CS curricula, materials, and learning environments. Study one was interviews with visually impaired developers; study two was interviews with K-12 teachers of visually impaired students; study three was a remote observation within a computer science course. My …

Wetland Uranium Transport Via Iron-Organic Matter Flocs And Hyporheic Exchange, Connor J. Parker

All Dissertations

Uranium (U) released from the M-Area at the Department of Energy Savannah River Site into Tims Branch, a seasonal wetland and braided stream system, is estimated to be 43,500 kg between 1965 and 1984. The motivation for this work is the uranium’s persistence in the wetland for decades, where it is estimated that 80% of the U currently remains in the Tims Branch wetland. U has begun to incorporate into wetland iron (Fe) and carbon cycles, associating with local Fe mineralogy and deposits of rich wetland organic matter (OM). The objective of this work is to characterize the chemical phases …

Penalized Estimation Of Autocorrelation, Xiyan Tan

All Dissertations

This dissertation explored the idea of penalized method in estimating the autocorrelation (ACF) and partial autocorrelation (PACF) in order to solve the problem that the sample (partial) autocorrelation underestimates the magnitude of (partial) autocorrelation in stationary time series. Although finite sample bias corrections can be found under specific assumed models, no general formulae are available. We introduce a novel penalized M-estimator for (partial) autocorrelation, with the penalty pushing the estimator toward a target selected from the data. This both encapsulates and differs from previous attempts at penalized estimation for autocorrelation, which shrink the estimator toward the target value of zero. …

Synthesis And Molecular Processes Governing Self-Healing Polymeric Materials, Siyang Wang

All Dissertations

Self-healing polymers capable of recovering from physical damages are promising materials for advanced technologies. In these studies, we developed routes to achieve self-healable properties in acrylic-based copolymers that rely on non-covalent dipolar interactions present in essentially all polymeric materials. Using a combination of spectroscopic tools, thermo-mechanical analysis, and molecular dynamic (MD) simulations, these studies have shown that dipolar interactions lead to conformational changes of macromolecular segments which, in turn, result in self-healing without external intervention. This dissertation also describes the development of novel self-healable acrylic-based covalent adaptable networks (CANs) that combine reprocessing and self-healing properties. The utilization of dipolar interactions …

Effects Of Forest Management On Early-Successional Avian Species In The Southern Blue Ridge Ecoregion, Michael J. Adams

All Theses

Early-successional habitats are a critical habitat type for Ruffed Grouse (Bonasa umbellus) and Golden-winged Warblers (Vermivora chrysoptera). In the Southern Blue Ridge Ecoregion, early-successional habitats have declined over the last 70 years, and the extent of which Ruffed Grouse and Golden-winged Warblers occupy these habitats at the edge of their ranges is unknown. Understanding the factors that drive the presence or absence of these species in this region is critical to inform quality management of early-successional forests. Additionally, increased knowledge of these species will likely benefit other species of conservation concern that rely on early-successional forests, …

Development Of A Machine Learning-Based Financial Risk Control System, Zhigang Hu

All Graduate Theses and Dissertations, Spring 1920 to Summer 2023

With the gradual end of the COVID-19 outbreak and the gradual recovery of the economy, more and more individuals and businesses are in need of loans. This demand brings business opportunities to various financial institutions, but also brings new risks. The traditional loan application review is mostly manual and relies on the business experience of the auditor, which has the disadvantages of not being able to process large quantities and being inefficient. Since the traditional audit processing method is no longer suitable some other method of reducing the rate of non-performing loans and detecting fraud in applications is urgently needed …

Studying The Role Of Cerebrovascular Changes In Different Compartments In Human Brains In Hypertension Prediction, Heba Kandil, Ahmed Soliman, Nada Elsaid, Ahmed Saied, Norah Saleh Alghamdi, Ali Mahmoud, Fatma Taher, Ayman El-Baz

All Works

Hypertension is a major cause of mortality of millions of people worldwide. Cerebral vascular changes are clinically observed to precede the onset of hypertension. The early detection and quantification of these cerebral changes would help greatly in the early prediction of the disease. Hence, preparing appropriate medical plans to avoid the disease and mitigate any adverse events. This study aims to investigate whether studying the cerebral changes in specific regions of human brains (specifically, the anterior, and the posterior compartments) separately, would increase the accuracy of hypertension prediction compared to studying the vascular changes occurring over the entire brain’s vasculature. …

Multi Elemental Analysis Of Cannabis Oil Based Products Using Icpms And Microwave Assisted Digestion., Kevin Trevon Marchbanks-Owens

Theses (2016-Present)

Due to the presence of CBD-(cannabidiol), bioavailable elements as well as industry versatility and relatively low levels of toxicity to the environment. CBD oils have driven the overall demand for Cannabis based plant products in the commercial and medical sector. However, dependent upon the environmental circumstances upon which these plants are grown can leave them susceptible to toxic heavy metal exposure. In fact, the natural metabolism of Cannabis plants makes them a hyperaccumulator of trace metals. This creates a severe health risk for CBD product consumers especially for more vulnerable populations with pre-existing conditions. Furthermore, the risk of heavy metal …

The Effects Of Water With Anti-Inflammatory Capabilities (Wac) On Circulating Inflammatory Biomarkers At Rest And Following Resistance Exercise, Brittany Martin

Health, Human Performance and Recreation Undergraduate Honors Theses

Purpose: To determine the effects of waters with anti-inflammatory capabilities (WAC) influence circulating inflammatory biomarkers at rest and following resistance exercise. Methods: Participants completed a heavy lifting protocol and drank water with anti-inflammatory capabilities for a total of six weeks. Blood samples were taken at different at 9 different time intervals to assess concentrations of anti-inflammatory markers and to quantify inflammatory biomarkers. Those time intervals included pre-AHREP 1 and post-AHREP 1, 24-hr post-AHREP 1, 48-hr post-AHREP 1, 3-week check-up, pre-AHREP 2, post-AHREP 2, 24-hr post-AHREP 2, and 48-hr post-AHREP 2. Background: The biomarkers that were focused on were: IL-6 …

Counterflow Dynamics Of Two Correlated Impurities Immersed In A Bosonic Gas, Friethjof Theel, Simeon I. Mistakidis, Kevin Keiler, Peter Schmelcher

Physics Faculty Research & Creative Works

The Counterflow Dynamics Of Two Correlated Impurities In A Double Well Coupled To A One-Dimensional Bosonic Medium Is Explored. We Determine The Ground-State Phase Diagram Of The System According To The Impurity-Medium Entanglement And The Impurities' Two-Body Correlations. Specifically, Bound Impurity Structures Reminiscent Of Bipolarons For Strong Attractive Couplings As Well As Configurations With Two Clustered Or Separated Impurities In The Repulsive Case Are Identified. The Interval Of Existence Of These Phases Depends Strongly On The Impurity-Impurity Interactions And External Confinement Of The Medium. Accordingly The Impurities' Dynamical Response, Triggered By Suddenly Ramping Down The Central Potential Barrier, Is Affected …