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Simulation Based Evaluation Of Multiscale Small Area Health Models, Purbasha Dasgupta

Theses and Dissertations

The effects of scale on the analysis of spatial data, often referred to as the modifiable areal unit problem in spatial studies, is one of the issues often encountered in small area health models. These spatial effects of scale are also seen in the areas of disease mapping where data are usually available in counts. Often there is a need to consider the different scales of aggregation that exist within count data, since inferences based on analyses can vary if we change the definition of the unit of analysis. This thesis provides a framework that describes the distribution of relative …

Remote Sensing Satellite Image Acquisition Planning: Framework, Methods And Application, Shufan Liu

Theses and Dissertations

This dissertation explores the theories and methods of satellite remote sensing image acquisition planning within a spatial temporal context. For many time sensitive applications, such as disaster emergency response, timely acquisition of critical information is the key to intelligent and effective decision making. Remote sensing plays an important role in information collection for these time sensitive applications. Imagery collected from hundreds of remote sensing satellite sensors offer accurate, frequent and almost instantaneous data covering the Earth in a relatively short time. However, determining which satellite sensors can provide an appropriated kind of imageries during a restricted collection window for the …

Toward The Combinatorial Development Of Hydrophobic-Tagged Antifolate-Directed Degradation Of Human Thymidylate Synthase, Daniel J. Menasco

Theses and Dissertations

Direct post-translational control over a protein of interest (POI) can be exploited by manipulating the cells protein quality-control systems responsible for either intracellular turnover through ubiquitination (POI half-life) or repairing and degrading misfolded proteins.1 In an effort to target and degrade a high value POI we selected the enzyme human thymidylate synthase (TS) for post-translational degradation through ligand-directed ubiquitination and hydrophobic tagging. Thymidylate synthase catalyzes the reductive methylation of 2’-deoxyuridine monophosphate (dUMP) to 2’-deoxythymidine monophosphate (dTMP). As the de novo source of dTMP the regulation of intracellular TS is strictly controlled by ubiquitinindependent proteasomal degradation mediated by an internal TS-degron …

Universal Two-Electron Correlation Operator On Excited States, Bryan Thomas Nichols

Theses and Dissertations

Excited states of chemical systems are extremely important in understanding spectra, chemical phenomena, as well as how a particular compound behaves in reactions. Computationally, excited states are normally very expensive to calculate. The difficulty in calculating these states with wavefunction based methods can be mainly attributed to the calculation of large multi-determinant wavefunctions. One reason to use a complicated multi-determinant wavefunction is to include some of the effects of correlation energy. The quantity of correlation energy can most simply be defined as the reduction in energy caused by any two or more electrons trying to avoid each other. The most …

Analysis Of Hurricane Preparedness Levels And Evacuation Intent For South Carolina Coastal Residents, Wesley Chad Seigler

Theses and Dissertations

Many communities across the nation, especially those in coastal areas, are experiencing extensive growth and expansion. This growth and the associated need for additional infrastructure, goods and services, and basic human needs often place people and the things they value in harm’s way due to the threat of a natural disaster. In order to properly prepare and mitigate disaster impacts, individuals and communities must view disasters as events that will likely occur at least once during their lifetime rather than simply outside possibilities. Residents of coastal communities must prepare for potential impacts from hurricanes and resulting storm surges and must …

Measurement Of Polarization Observables PZ, PSZ, And PCZ In Double-Pion Photoproduction Off The Proton, Yuqing Mao

Theses and Dissertations

Meson production from excited nucleons is important in the study of baryon resonances and pion photoproduction is attracting much attention. To date a rather large amount of unpolarized cross-section measurements have been reported for both single- and double-pion photoproduction. However, polarization observables provide complementary information as they probe different combinations of transition amplitudes. The database for polarization observables remains quite sparse. Double-pion photoproduction have been studied in Hall B at Jefferson Lab with linearly polarized tagged photon beams incident on longitudinally polarized protons. The experiment covered center-of-mass energies between 1.4 GeV and 2.3 GeV. The target was a FROzen Spin …

Semiparametric Regression Analysis Of Bivariate Interval-Censored Data, Naichen Wang

Theses and Dissertations

Survival analysis is a long-lasting and popular research area and has numerous applications in all fields such as social science, engineering, economics, industry, and public health. Interval-censored data are a special type of survival data, in which the survival time of interest is never exactly observed but is known to fall within some observed interval. Interval-censored data arise commonly in real-life studies, in which subjects are examined at periodical or irregular follow-up visits. In this dissertation, we develop efficient statistical approaches for regression analysis of bivariate intervalcensored data, in which the two survival times of interest are correlated and both …

Temporal Constraints On Holocene Initiation And Termination Of Mound Development At An Episodic Gas Hydrate And Cold Seep System, Woolsey Mound, Northern Gulf Of Mexico, Nathan Robinson

Theses and Dissertations

Woolsey Mound is a thermogenic gas hydrate and cold seep system in the deepwater (900m) Gulf of Mexico. A set of sub-bottom seismic profiles acquired at MC-118 Woolsey Mound provide decimeter-scale vertical resolution of the upper ~50m of the subsurface throughout the lease block. Integration of these data with radiocarbon, lithostratigraphic, and biostratigraphic data from shallow gravity cores provides the basis for detailed interpretation of the mound evolution within the last 12,000 years. Uniform sedimentation during the Last Glacial Maximum and following changes in sediment distribution over MC-118 suggests modern mound activity did not begin until at least ~12ka. Development …

The Geologic Implications Of The Factors That Affected Relative Sea-Level Positions In South Carolina During The Pleistocene And The Associated Preserved High-Stand Deposits, William Richardson Doar Iii

Theses and Dissertations

This work utilizes the current understanding of South Carolina geology to provide a stratigraphic review of the late-Pliocene and Pleistocene marine deposits. Almost two centuries of recorded geological study includes geomorphic and stratigraphic units that were described, proposed, revised, abandoned, and revived. Along with the history of the age assignments, changes in geological time scales, and the changes in the understanding of geological concepts, this review is necessary because two concurrent and conflicting stratigraphies exist for late-Pliocene and Pleistocene marine sediments that record multiple sea-level transgressions that were more often destructive than constructive. The result, when tested against existing geological …

Climate-Induced Changes In The Germination Phenology Of Boechera Stricta, Samuel Johnson

Theses and Dissertations

Climate change is having demonstrable, worldwide impacts on ecological systems in ways that have modified aspects of organism behavior. Plant phenologies have responded to warmer temperatures in a variety of ways that may have implications for long-term species survival. How germination phenology changes in response to warmer climate is a largely unexplored question yet the ability of a plant to advance or delay germination in unfavorable conditions is critical for survival. Knowing the relative success and timing of germination under different climate regimes is important in understanding whether species can keep pace with the rate of climate change via migration …

Methods For Identifying Regions Of Brain Activation Using Fmri Meta-Data, Meredith A. Ray

Theses and Dissertations

Functional neuroimaging is a relatively young discipline within the neurosciences that has led to significant advances in our understanding of the human brain and progress in neuroscientific research related to public health. Accurately identifying activated regions in the brain showing a strong association with an outcome of interest is crucial in terms of disease prediction and prevention. Functional magnetic resonance imaging (fMRI) is the most widely used method for this type of study as it has the ability to measure and identify the location of changes in tissue perfusion, blood oxygenation, and blood volume. In practice, the three-dimensional brain locations …

Cationic Metallocene-Containing Polymers: From Synthesis To Applications, Jiuyang Zhang

Theses and Dissertations

Metallopolymers, with the combination of metals and polymeric framworks, have attracted a lot of attention during the past decades. The development of metallopolymers has been largely driven by the desire to combine the synthetic efficiency and versatility of an organic polymer framework with the unique redox, responsive and catalytic properties of inorganic metals. Among different kinds of metallopolymers, metallocene-containing polymers， have been widely utilized for applications ranging from electrochemical sensors to templates for advanced inorganic catalysts to battery materials, due to their unique physicochemical properties. In the first part of my thesis, we showed controlled/living polymerization strategies to prepare well-defined …

Surface Functionalization Of Inorganic Substrates With Polymeric Ligands Using Raft Polymerization, Anand Viswanath

Theses and Dissertations

This work focused on using polymers to modify the surface of various inorganic substrates, ranging from TiO2, ITO, CDSe and CdS nanostructures to micron sized silica particles. The synthesis of the polymers using the RAFT technique and the characterization of the functionalized substrates were analyzed in detail to provide insights into their use for various applications. In the first part of this work, novel phosphate based RAFT agents and phosphate containing polymers, including poly(methyl methacrylate) (PMMA), poly(glycidyl methacrylate) (PGMA) and poly(dimethyl siloxane) (PDMS) were synthesized. Alkyne functionalized PGMA was used to click to ITO surfaces in a grafting-to method, and …

Modeling Mussel Mortality: Investigating The Importance Of Swash And The Potential Implications Of Changing Wave Environments, Shadow Leigh Gulledge

Theses and Dissertations

Rising sea level and increases in temperature are causing biogeographic shifts in intertidal zones and can also lead to shifts in the local vertical zonation of organisms due to changes in body temperature during aerial exposure during low tide. Swash is an important determinant of aerial body temperatures, and vulnerability of intertidal zones to changes in climate could potentially depend on how much and how often animals are cooled by waves. While wave heights (and thus swash) are generally expected to increase with climate change, anthropogenic physical structures, such as breakwaters and wave energy converters, can decrease wave height and …

Genes Mediating Cardiac Remodeling During Pregnancy And The Early Post-Partum-Period In Mice, Esam Aljrbi

Theses and Dissertations

The female heart undergoes adaptive remodeling during pregnancy to compensate for the increased hemodynamic load imposed by the developing fetus. However, unlike a similar adaptive process which occurs under pathological conditions (such as hypertension and valvular heart disease) the cardiac changes observed during hypertrophy associated with pregnancy are reversible. The goal of this study is to identify changes in gene expression associated with pregnancy-induced hypertrophy. We tested the hypothesis that pregnancy-induced physiological hypertrophy has a unique genetic signature, likely due to altered hormone levels, which supports and promotes reversible remodeling. Comparing the gene expression profile associated with physiological remodeling with …

Biopolymeric Hydrogels Functionalized With Tobacco Mosaic Virus For In Vitro Three Dimensional Culture And Differentiation Of Stem Cells And In Vivo Tissue Regeneration, Jittima Amie Luckanagul

Theses and Dissertations

Plant viruses have been highlighted among material research due to their well-defined structures in nanoscale, mono-dispersity, stability, and chemical functionalities. Each of the thousands coated protein subunits on a viral nanoparticle can be homogenously modified, chemically, and genetically with a functional ligand leading to a high-density and spatial distribution of ligands on each particle (multivalency). Many reports from our group have clearly shown that virus coated substrates induced the acceleration of bone marrow stromal cells differentiation into bone cells. We hypothesized that this phenomenon could rely on the multivalency that the viral nanoparticle has to offer. Moving to a more …

Investigation Into The Synthesis And Characterization Of Poly(Dioxaborolane)S, Shakena Daniel

Theses and Dissertations

Boronate esters have evolved from being primarily used as sensors to being the integral linkage in complex materials such as macrocycles, covalent organic frameworks, and linear polymers. Poly(boronate)s, linear polymers that are linked via a boronate ester, have not been extensively researched. In 2005, the Lavigne group published the first manuscript on poly(dioxaborolane)s, i.e., six-membered, nonconjugated polyboronates. The behavior of the materials in solution was studied extensively, but little is known about the solid state properties of the material other than they form brittle films.

Poly(dioxaborolane)s are generated in high yield through a facile step-growth polymerization, but the reaction parameters, …

Network Analysis And Cluster Detection Using Markov Theory, John William Campbell

Theses and Dissertations

Networks are a vital part of nature and society, yet many aspects of how networks function are still largely unknown. From understanding the internet to biology, chemistry, and physics, networks play a role, but even some of the most basic questions about networks can be difficult to answer. How are two networks alike or different? How do networks within networks form and how can clusters be detected? As networks change with time, how can we monitor those changes? The answers to these questions are vitally important to humans’ understanding of the world. Better understanding of networks allows for things like …

Explorations In Elementary And Analytic Number Theory, Scott Michael Dunn

Theses and Dissertations

In this dissertation, we investigate two distinct questions in number theory. Each question is dedicated its own chapter.

First, we consider arithmetic progressions in the polygonal numbers with a fixed number of sides. We will show that four-term arithmetic progressions cannot exist. We then describe explicitly how to find all three-term arithmetic progressions. Additionally we show that there are infinitely many three-term arithmetic progressions starting with an arbitrary polygonal number.

Second, we will show certain irreducibility criteria for polynomials. Let f(x) be a polynomial with non-negative integer coefficients such that f(b) is prime for some integer 2 ≤ b ≤ …

Synthesis, Characterization And Optical Properties Of Conjugated Boronate-Linked Materials And Their Applications In Optical Sensing Of Lewis Bases, Min Cai

Theses and Dissertations

Organoboron compounds, with Lewis acidic boron centers, have been emerged as an important class of materials, especially in the area of chemical sensors. Herein, boranes and boronate esters in the sensing perspective were overviewed in Chapter 1. Examples of synthesis and sensing applications of boron-containing conjugated polymers were highlighted.

Boronate ester formation provides the advantages of facile synthesis, tunable optical properties, enhanced stability and planar geometry. Thus, boronate esters, especially dioxaboroles, were proposed to use as alternatives of boranes to design better sensors for Lewis bases. Based on the previous investigation of fluorenyl bis- and poly- dioxaboroles by our group, …

Physical And Magnetic Properties Of Magnetic Nanoparticle Arrays, Abdul Rahman Mohtasebzadeh

Theses and Dissertations

Using Scanning Electron Microscope (SEM) , Atomic Force Microscope (AFM) and Vibrating Sample Magnetometer (VSM) I studied magnetic-field directed self-assembly of magnetic nanoparticles into patterned arrays on the surface of perpendicular magnetic recording media. A controllable machine was used to coat super paramagnetic nano particles onto the surface of perpendicular recording media for different time intervals. Self assembled nano particles on the surface of the media, were transferred to a polymer layer to observe physical properties. Results from imaging shows that the average width and height of arrays is increasing as a function of time. Width of arrays varies with …

Potential Stormwater Runoff Reductions By Incorporating Low Impact Development: Rocky Branch Watershed, Columbia, Sc, Brett Sexton

Theses and Dissertations

Urbanization and increasing population are primary sources of water degradation, increased flood risks, and channel morphological instability. Impervious surface areas increase with urbanization and result in decreased infiltration capactities, increased stormwater runoff, and more rapid stormwater delivery, which in turn increase flood magnitudes and frequencies. Low impact development (LID) can provide volumetric detention storage to reduce flooding. This thesis reviews types of LID, their attributes and limitations, and examines how effectively they can abstract storm runoff volumes, reduce peak discharge, and delay stormwater arrival times for relatively frequent storm events in the Rocky Branch Watershed (RBW).

The RBW is 50% …

Flow Dynamics In The Transition Zone From Estuarine Tidal To Fluvial Regime In The Santee River, Sc, Usa, Legna M. Torres-Garcia

Theses and Dissertations

Estuaries are important systems that link fresh, inland waters to oceanic salt water, where they act to deliver large amounts of nutrients, sediments and pollutants into the ocean. Traditionally, the study of estuarine systems has been marked by difficulty owing to the complex hydrodynamics influenced by strong bathymetric changes, changes in tidal range, intricate geomorphology, among other factors; thus beginning to unravel the complexities of estuarine hydrodynamics will help to illuminate the nature of estuaries as well as to provide a foundation for their further study. In this study I focus on the transition zone from tidal to fluvial regime, …

Galaxies In Absorption: A Study Of Chemical And Kinematic Properties Of Sub-Damped Lyman-Alpha Quasar Absorbers, Debopam Som

Theses and Dissertations

Study of the chemical composition of the interstellar medium (ISM) in galaxies over cosmic time is essential for a coherent understanding of galaxy formation and evolu- tion. Absorption lines in the spectra of quasars can be used as powerful, luminosity- independent probes of the properties of gas in and around galaxies and have been used extensively to study galaxies, the circumgalactic medium (CGM) and the intergalac- tic medium (IGM). The Damped Lyman-α systems (DLAs), with neutral hydrogen column densities of log NHI & 20.3, and sub-Damped Lyman-α systems (sub-DLAs) with 19.0 . log NHI < 20.3 are the highest NHI quasar absorbers and contain the most of the neutral gas available for star formation in the high-redshift Universe. These systems are believed to trace the progenitors of present-day galaxies and ac- curately probe chemical abundances in the ISM over ∼ 90% of the cosmic history. In contradiction with the cosmic chemical evolution models which predict the mean metallicity of galaxies to rise from low metallicities at high-z to a near-solar level at z ∼ 0, the DLAs are typically found to be metal-poor at all redshifts, showing little or no evolution. Interestingly, past work showed that the sub-DLAs at 0.6 . z . 1.5 are more metal-rich on average than DLAs, and evolve consistently with the chemical evolution models in this redshift range. This suggests that the DLAs and sub-DLAs may be tracing the progenitors of different populations of present-day galaxies. How- ever, chemical evolution of sub-DLAs is poorly constrained outside of the redshift range 0.6 < z < 1.5 which hinders a better understanding of galaxy evolution traced by DLAs and sub-DLAs.

This dissertation presents chemical abundance measurements …

On The Electrovacuum Solutions To The Einstein-Maxwell System In General Relativity, Nelson Camilo Posada Aguirre

Theses and Dissertations

In this masters thesis, we will present the analysis of the solution to the Einstein field equation, known as electrovac universe. In this model, an electric charge is located somewhere in an empty universe. An important result from this scenario, is that there is a functional relation between the electrostatic potential and the metric components, asumming a comformastat metric. On the other hand, the Einstein’s equations implies that the metric function satisfy the Laplace equation. We extended this model considering the Einstein’s equation with cosmological constant, which increased the complexity of the equations. The metric function satisfies now a nonlinear …

Synthesis And Characterization Of Polymer Nanomaterials Using Controlled Radical Polymerization, Lei Wang

Theses and Dissertations

This research focuses on creating and investigating polymer/organic bound interfaces on nanoparticles with advanced architectures to tailor the properties of polymer nanocomposites for various applications. Reversible addition-fragmentation chain transfer (RAFT) polymerization and a toolbox of surface functionalization from the simple to the advanced were developed to prepare the polymer nanomaterials.

In the first part (Chapter 2), a variety of RAFT agents (xanthate, dithiocarbamate and trithiocarbonate) were used to mediate the polymerizations of several classes of free radical polymerizable monomers. These monomers consist of styrene, methyl acrylate, methyl methacrylate, vinyl acetate and isoprene, which have different activities and require different classes …

The Non-Existence Of A Covering System With All Moduli Distinct, Large And Square-Free, Melissa Kate Bechard

Theses and Dissertations

The work in this thesis is based on a paper written by Bob Hough in 2013. This thesis addresses the conjecture posed by Erdos that the least modulus for a covering system can be arbitrarily large. Hough proves the least modulus cannot be arbitrarily large. In this thesis, we present Hough’s proof for the case of square-free moduli.

Novel Monomers And Solution Polymerization Methods For Polybenzimidazole Polymers, Jason Hoffman

Theses and Dissertations

The goal of this work was to identify and study various monomers and polymerization methods for polybenzimidazole polymers. Beginning with the solution polymerization of polybenzimidazole via a bisulfite adduct monomer, Chapter 2 describes the efforts to optimize and scale up this process. Chapter 3 then covers an alternative method to prepare polybenzimidazole in solution by using an orthoester monomer. Finally, in Chapter 4, the research to incorporate an adamantane moiety into the backbone of polybenzimidazole is described.

Garzón Massif Basement Tectonics: A Geopyhysical Study, Upper Magdalena Valley, Colombia, Kadir Baris Bakioglu

Theses and Dissertations

The mechanics and kinematics of basement tectonic uplifts, such as the Laramide Rocky Mountain orogeny, remain poorly understood and controversial. The debate continues in part because of the limited number of well-documented present day analogs. The Garzón Massif rising between the Upper Magdalena Valley and the Llanos Basin of Colombia is an active basement uplift with well, seismic, gravity, and magnetic data available. In the past 10 Ma, PreCambrian age granitic rocks of the Garzón Massif have been uplifted and displaced against Cretaceous and Tertiary sediments of the Upper Magdalena Valley along the Garzón fault.

Aerogravimetric data calibrated by well …

Mechanistic Investigation Of A Silylation-Based Kinetic Resolution Using Linear Free Energy Relationships And Its Application To Substrate Expansion And Polymer Supported Kinetic Resolutions, Ravish K. Akhani

Theses and Dissertations

This dissertation represents our preliminary mechanistic investigations on the silylation-based kinetic resolution of secondary alcohols, and how we use that knowledge for further expansion of this methodology. Chapter 2 describes how we came up with a preliminary mechanism of our silylation-based methodology using a linear free energy relationship and a rate study. In this chapter, several para substituted triphenylsilyl chlorides were prepared that varied electronically and sterically in order to understand the substituent effects on the rate and the selectivity of the reaction. Selectivity factors and initial rates were experimentally determined for the kinetic resolution reactions with the newly designed …