Physical Sciences and Mathematics Commons^™

Assessment Of Upper Cretaceous Strata For Offshore Co2 Storage: Southeastern United States, Khaled F. Almutairi

Theses and Dissertations

This is the first assessment of Upper Cretaceous strata for offshore CO2 storage resources in the southeastern United States outer continental shelf. This research focuses on Upper Cretaceous geological units using legacy industry 2-D seismic reflection and well data. It provides an integrated description and reliable subsurface evaluation of Upper Cretaceous potential storage reservoirs. In addition, it provides a detailed evaluation on how rock porosities and permeabilities are distributed across the Upper Cretaceous strata restricted to the South Georgia Embayment (SGE). Structure and thickness (isochore) maps were generated for the main potential reservoirs and seals on a regional and local …

Design, Synthesis, Characterization, And Applications Of Matrix Free Polymer Nanocomposites, Yucheng Huang

Theses and Dissertations

This dissertation focuses on the design, synthesis, characterization and application of matrix free polymer nanocomposites. Reversible addition-fragmentation chain transfer (RAFT) polymerization was used to synthesize block copolymers and polymer grafted silica nanoparticles with precise control over architectures.

In the first chapter, thermoplastic elastomer (TPE) grafted nanoparticles were prepared by grafting block copolymer poly(styrene-block-(n-butyl acrylate)) onto silica nanoparticles (NPs) (~15nm) via surface initiated RAFT polymerization. The effects of polymer chain length and graft density on the mechanical properties were investigated using films made solely from the grafted NPs. The ultimate tensile stress and elastic modulus increased with the increase of PS …

Instrumentation For, And Application Of, Novel Electrochemical Tools For In Vivo Analysis Of Neurotransmitters In The Context Of Psychiatric Disease, Rhiannon Robke

Theses and Dissertations

ABSTRACTSerotonin’s involvement in many physiological processes including anxiety, stress, compulsivity, and mood has been speculated for decades. Insufficient progress in our understanding of serotonin chemistry is due to the lack of effective tools to selectively measure this neurotransmitter on a neurotransmission-relevant time scale in vivo. An analytical technique for serotonin measurements, fast-scan cyclic voltammetry (FSCV), was pioneered in the last decade in anesthetized rodents and is beginning to shed light on the complexity of serotonergic activity on a sub-second timescale. Complementary, more recent technological innovations have enabled ambient neurotransmitter levels to be determined every few seconds using a method called …

Optical Investigation Of A Hybrid System Of Plasmonic Structures And Semiconductor Quantum Dots, Matthew B. Seaton

Theses and Dissertations

Next generation integrated nanophotonic devices must fabricate large numbers of nanoscaled light coupling structures onto a single wafer: emitters such as quantum dots, resonators such as nanocavities and plasmonic nanoparticles, photonic crystal and nano-plasmonic waveguides, among others. Before precision planning and engi- neering will be possible a thorough understanding of the interaction between these structures must be documented. We present in this work an investigation of the interaction between quantum dots and plasmonic structures in the weak coupling regime. We found that surface plasmon supporting silver structures placed about 100nm from InGaAs quantum dots enabled an all optical polarization dependent …

Regulation Of Cytoplasmic Dynein By Lis1 And Adenomatous Polyposis Coli, Timothy Joshua Hines

Theses and Dissertations

Cytoplasmic dynein 1 (dynein) is a microtubule motor that plays a role in mitosis, cell migration, and minus-end directed microtubule-based transport. The lissencephaly protein, Lis1, and its binding partner, Ndel1, are critical regulators of cytoplasmic dynein (Niethammer et al., 2000). In humans, haploinsufficiency of Lis1 leads to lissencephaly, a devastating developmental neurological disorder characterized by severe brain malformation, leading to cognitive and motor defects, and progressively worsening seizures (Dobyns et al., 1993). While Lis1 is known to play a role in regulating dynein-dependent functions such as neuronal migration and mitotic spindle orientation during development, the protein is still highly expressed …

Understanding The Adsorption And Nucleation Of Transition Metals On A Model Carbon Support, Grant S. Seuser

Theses and Dissertations

Heterogeneous catalysis plays a vital role in the commercial production of chemicals. However, much is still unknown about the fundamental surface chemistry involved in catalyst preparation and the surface chemistry of the catalysts themselves. In the first part of this work, a surface science approach was employed to develop a fundamental understanding of the surface chemistry of strong electrostatic adsorption (SEA) of metal precursors on a model carbon support, highly oriented pyrolytic graphite (HOPG). SEA is a wet impregnation method in which anionic/cationic metal precursors are adsorbed onto positively/negatively charged functional groups by adjusting the pH of the solution above …

Discovery Of Community Structures In Static And Dynamic Networks, Shiwen Shen

Theses and Dissertations

With the development of computer technology, researchers are able to observe and collect enormous amount of data, where the independent and identical distributed assumption is violated. For example, in sociology, individuals in an organization interact with each other to change the underlying social structure; in biology, understanding the gene-gene interaction helps researchers to detect potential diseases; in politics, voters are mutually influenced before the election via private/public speeches and parades, which might ultimately change the election results. It is crucial to study how individuals interact with each other from the data, which would lead to tremendous contributions to the society. …

Iron Transport Machinery: A Potential Therapeutic Target In Escherichia Coli, Clorissa L. Washington – Hughes

Theses and Dissertations

Iron metabolism is an integral part of life for most organisms. Despite its essentiality, iron can also become toxic. There are many aspects to maintaining iron balance within the cell. The aim of this work is to provide insight into the function of several components involved in bacterial iron homeostasis. This work is significant for the development of novel antibiotics for treating resistant or pathogenic bacteria. Herein, it is shown that nickel can disrupt normal bacterial iron metabolism and that bacterial resistance can be affected by expression of iron acquisition genes. Once iron is obtained by the cell, it can …

Branching Fractions And Amplitude Analysis Of B± → Φks0Π± Decays, Alyssa D. Loos

Theses and Dissertations

The Belle detector is a particle physics detector that is located around the collision point of the asymmetric-energy e+e- collider KEKB. Both detector and collider are located at the KEK international lab in Japan. This thesis uses the full Belle data sample of 772 × 106 BB¯ pairs collected at the Υ(4S) resonance. Decays with large b → s penguin transitions in the standard model (SM), such as B± → φKS0π±, could be a source of CP violation. This is important in the race to find the mechanism behind the universe’s matter-antimatter imbalance. b → s penguin transitions allow us …

Implementation Costs Of Spiking Versus Rate-Based Anns, Lacie Renee Stiffler

Theses and Dissertations

Artificial neural networks are an effective machine learning technique for a variety of data sets and domains, but exploiting the inherent parallelism in neural networks requires specialized hardware. Typically, computing the output of each neuron requires many multiplications, evaluation of a transcendental activation function, and transfer of its output to a large number of other neurons. These restrictions become more expensive when internal values are represented with increasingly higher data precision. A spiking neural network eliminates the limitations of typical rate-based neural networks by reducing neuron output and synapse weights to one-bit values, eliminating hardware multipliers, and simplifying the activation …

Comparison Of The Performance Of Simple Linear Regression And Quantile Regression With Non-Normal Data: A Simulation Study, Marjorie Howard

Theses and Dissertations

Linear regression is a widely used method for analysis that is well understood across a wide variety of disciplines. In order to use linear regression, a number of assumptions must be met. These assumptions, specifically normality and homoscedasticity of the error distribution can at best be met only approximately with real data. Quantile regression requires fewer assumptions, which offers a potential advantage over linear regression. In this simulation study, we compare the performance of linear (least squares) regression to quantile regression when these assumptions are violated, in order to investigate under what conditions quantile regression becomes the more advantageous method …

Theory, Computation, And Modeling Of Cancerous Systems, Sameed Ahmed

Theses and Dissertations

This dissertation focuses on three projects. In Chapter 1, we derive and implement the compact implicit integration factor method for numerically solving partial differential equations. In Chapters 2 and 3, we generalize and analyze a mathematical model for the nonlinear growth kinetics of breast cancer stem cells. And in Chapter 4, we develop a novel mathematical model for the HER2 signaling pathway to understand and predict breast cancer treatment. Due to the high order spatial derivatives and stiff reactions, severe temporal stability constraints on the time step are generally required when developing numerical methods for solving high order partial differential …

Dually Modified Transmembrane Proteoglycan Tβriii/Betaglycan In Cell Signaling And Cancer, Laura M. Jenkins

Theses and Dissertations

During tumor progression, cancer cells undergo a number of alterations to evade tumor inhibitory mechanisms, proliferate, invade surrounding tissues and metastasize to distant sites. These properties reflect changes in their cell signaling pathways that, in normal cells, control aberrant cell proliferation, motility, and survival. Over the past few decades, hyperactive Wnt/β-catenin signaling has been linked to the formation of multiple cancers, including malignant ovarian cancer, making identification of molecules regulating Wnt/β-catenin signaling crucial to the development of early detection methods and cancer treatment strategies. Proteoglycans, which regulate transmission of cellular signals, are implicated in the pathophysiology of diseases, including cancer, …

The Sedimentary Record Of Eocene Deformation In The Interior Of The Southern Canadian Cordillera, Erica May Rubino

Theses and Dissertations

Eocene sedimentary strata exposed in the interior of the southern Canadian Cordillera (SCC) in British Columbia (BC) and northernmost Washington (WA) record a poorly understood history of extension-related deformation in the hinterland of the orogen. Today these strata are exposed in isolated, distinct outcrop belts, although the nature of the original basin(s) is unknown. We examined 650 m of Eocene strata, analyzed 2,995 detrital zircons for uranium-lead (U-Pb) ages, and measured 67 detrital zircons for Hf isotope systematics in an effort to better understand the physiography of the SCC during this time period. Eocene strata consist of clast- and matrix-supported …

Geometry Of Derived Categories On Noncommutative Projective Schemes, Blake Alexander Farman

Theses and Dissertations

Noncommutative Projective Schemes were introduced by Michael Artin and J.J. Zhang in their 1994 paper of the same name as a generalization of projective schemes to the setting of not necessarily commutative algebras over a commutative ring. In this work, we study the derived category of quasi-coherent sheaves associated to a noncommutative projective scheme with a primary emphasis on the triangulated equivalences between two such categories.

We adapt Artin and Zhang’s noncommutative projective schemes for the language of differential graded categories and work in Ho (dgcatk), the homotopy category of differential graded categories, making extensive use of Bertrand Toën’s Derived …

Quick Trips: On The Oriented Diameter Of Graphs, Garner Paul Cochran

Theses and Dissertations

In this dissertation, I will discuss two results on the oriented diameter of graphs with certain properties. In the first problem, I studied the oriented diameter of a graph G. Erdos et al. in 1989 showed that for any graph with |V | = n and δ(G) = δ the maximum the diameter could possibly be was 3 n/ δ+1. I considered whether there exists an orientation on a given graph with |G| = n and δ(G) = δ that has a small diameter. Bau and Dankelmann (2015) showed that there is an orientation of diameter 11 n/ δ+1 + …

Salt Tectonism In The Carolina Trough, Ceren Postaagasi

Theses and Dissertations

The Carolina Trough is a major linear sedimentary basin along the eastern continental margin of North America which formed as a result of tectonic and thermal subsidence during continental rifting in Mesozoic time (Hutchinson et al., 1982). The Carolina Trough is unique along the southeastern U.S. margin where the only known evaporite deposits are found, and this salt basin may reserve large amounts of oil and gas (Carpenter & Amato, 1992). Therefore, analysis of 2D multichannel seismic reflection surveys that were conducted in the Mid-South Atlantic Ocean in 1982 plays an important role in Petroleum industry. In addition, current interpretations …

Organic Acids And Amino Acids In Serpentinization Related Fluids From The Atlantis Massif, Nicholas Camper

Theses and Dissertations

Serpentinization is a low temperature, low pressure process that occurs when water reacts with ultramafic rocks. Fluids that have interacted with serpentinites have elevated concentrations of hydrogen and reduced carbon species that can fuel chemolithoautotrophy. International Ocean Discovery Program Expedition 357 drilled a series of boreholes into the Atlantis Massif with the goal of investigating how serpentinization impacts carbon cycling and sustains life in the subseafloor. Bottom water samples (CTD), fluids flushed from the boreholes during drilling (Rock Drill), and fluids that were trapped in the liners of the cores (Liner fluids) were collected. The changes and distributions of organic …

Estimation Procedures For Complex Survival Models And Their Applications In Epidemiology Studies, Jie Zhou

Theses and Dissertations

In this dissertation, we aim to address three important questions in practice, which can be solved through complex survival models. The first project focuses on studying the longitudinal fitness effect on cardiovascular disease (CVD) mortality. In the second project, we study the disease-death relation between CVD and all-cause mortality and evaluate important covariate effects on the disease or death transitions. In the third project, we compare antiretroviral treatment (ART) for HIV patients and consider both treatment effect and side effect of the drugs. The first two projects are motivated by the Aerobics Center Longitudinal Study (ACLS) datasets and the third …

Block Copolymer Control Of Nanoscale Porous Materials, Amrita Sarkar

Theses and Dissertations

The controlled fabrications of porous materials are crucial for a wide variety of uses spanning the gamut from energy applications to filtration. Despite decades of developments based upon block copolymer self-assembly there remain numerous limitations to achieve simple ends such as fully-tunable nanomaterials or well-defined macroscopic forms. For example, fundamental studies of nanostructure-performance relationships need systematic series of nanomaterials to identify the separate effects of wall and pore dimensions. Such precision control is impossible under the constraints of equilibrating systems. Persistent Micelle Templating (PMT) is rather based on kinetic control and enables robust and independent tuning of each feature. However, …

Ecology And Virulence Capabilities Of Vibrios Isolated From The Pristine North Inlet Estuary, Savannah Leigh Klein

Theses and Dissertations

Vibrio bacteria are Gram negative, motile organisms that occur naturally in most coastal and estuarine ecosystems. Some vibrios are important human pathogens, including Vibrio parahaemolyticus and Vibrio vulnificus. The CDC estimates that vibrios cause 80,000 cases of disease each year in the United States alone. Most cases are caused by V. parahaemolyticus, which infects humans after the consumption of contaminated raw or undercooked seafood, primarily oysters. V. parahaemolyticus causes mild gastroenteritis that is self-limiting unless the patient is immunocompromised. V. vulnificus has a much lower incidence of disease (100 cases in the USA yr-1); however, this organism causes much more …

Hydrothermal Synthesis: A Gateway To Metastable Crystals With Unusual Properties, Justin B. Felder

Theses and Dissertations

Research into crystalline matter has long been of interest to humanity, both in order to advance our society by creating new technologically useful materials and in order to better understand to nature of the properties we depend on for so much of our existing technology. In recent decades, solution-based crystal growth syntheses including hydrothermal and molten flux techniques have risen to the forefront of solid-state chemistry as superior methods of synthesizing new materials as single crystals ripe for structure determination and property measurements.

This work seeks to educate readers on recent advances in the hydrothermal realm of crystal growth: namely …

Depairing Current Density In Nbtin Superconducting Films, Nahid Shayesteh Swails

Theses and Dissertations

In this work, we systematically investigate the superconducting properties of Niobium Titanium Nitride (NbTiN) superconducting films with different geometries, which at low temperature remain superconducting. NbT iN superconducting films with a few nm thickness are widely used in devices such as superconductor-insulatorsuperconductor (SIS) mixers, superconducting cavities and resonators and superconducting nanowire single-photon detectors (SNSPD). In all these applications, films of varying dimensions are required to achieve optimal performance. The initial thickness of our samples was 125 nm deposited on a silicon substrate. We change the thickness of our samples using lithography and ion milling. We measure and analyze the thickness …

Semiparametric Regression In The Presence Of Measurement Error, Xiang Li

Theses and Dissertations

The error-in-covariates problem has received great attention among researchers who study semiparametric and nonparametric inference for regression models over the past two decades. Without correcting for the measurement error in covariates, estimators for covariate effect usually contain bias. To account for measurement error, much research have been done in mean regression (Liang et al., 1999; Fuller, 2009; Carroll et al., 2006) and quantile regression (He and Liang, 2000; Hardle et al., 2000; Wei and Carroll, 2009). In contrast, there is little research in mode regression and this motivates us to propose semiparametric methods to address this error-incovariates problem in Chapters …

Uncertainty Estimation Of Deep Neural Networks, Chao Chen

Theses and Dissertations

Normal neural networks trained with gradient descent and back-propagation have received great success in various applications. On one hand, point estimation of the network weights is prone to over-fitting problems and lacks important uncertainty information associated with the estimation. On the other hand, exact Bayesian neural network methods are intractable and non-applicable for real-world applications. To date, approximate methods have been actively under development for Bayesian neural networks, including but not limited to: stochastic variational methods, Monte Carlo dropouts, and expectation propagation. Though these methods are applicable for current large networks, there are limits to these approaches with either underestimation …

Inorganic Nanocrystals And Their Applications In Hybrid 0d:2d Material Optoelectronics, Mathew Kelley

Theses and Dissertations

Functional nanomaterials have garnered great interest as candidates for use in next-generational optoelectronics such as solar photovoltaics, light-emitting diodes, and photodetectors. Among these low-dimensional materials, hybrid devices employing both 0D and 2D materials are of interest due to exploitation of the favorable characteristics of each component, and performances superior to standalone counterparts are achievable. This thesis is divided into two parts, as follows. The first two chapters will introduce lowdimensional materials and their favorable characteristics; our work on the formation of ligand-exchanged nanocrystal thin films purified by gel-permeation chromatography will also be discussed. In the second component, the formation and …

Machine Learning Based Disease Gene Identification And Mhc Immune Protein-Peptide Binding Prediction, Zhonghao Liu

Theses and Dissertations

Machine learning and deep learning methods have been increasingly applied to solve challenging and important bioinformatics problems such as protein structure prediction, disease gene identification, and drug discovery. However, the performances of existing machine learning based predictive models are still not satisfactory. The question of how to exploit the specific properties of bioinformatics data and couple them with the unique capabilities of the learning algorithms remains elusive. In this dissertation, we propose advanced machine learning and deep learning algorithms to address two important problems: mislocation-related cancer gene identification and major histocompatibility complex-peptide binding affinity prediction. Our first contribution proposes a …

Hierarchical Corannulene-Based Materials, Allison M. Rice

Theses and Dissertations

Merging the intrinsic properties of fullerene (buckyball) and corannulene (buckybowl) derivatives with the inherent properties of crystalline metal- and covalentorganic frameworks (MOFs and COFs), including their modularity, porosity, versatility, high surface area, and structural tunability, opens a pathway to unlock a novel class of fulleretic materials. Despite the great interest in MOFs and COFs, as well as fullerene derivatives, this dissertation is focused on crystalline fullerene- and corannulenecontaining frameworks, highlighting their potential contributions in the fields of optoelectronic devices, electrodes, and photosensitizers. We have revealed a dual role of fullerene- and corannulene-containing building blocks showing their versatility to act as …

Local Rings And Golod Homomorphisms, Thomas Schnibben

Theses and Dissertations

The Poincaré series of a local ring is the generating function of the Betti numbers for the residue field. The question of when this series represents a rational function is a classical problem in commutative algebra. Golod rings were introduced by Golod in 1962 and are one example of a class of rings that have rational Poincaré series. The idea was generalized to Golod homomorphisms by Levin in 1975.

In this paper we prove two homomorphisms are Golod. The first is a class of ideals such that the natural projection to the quotient ring is a Golod homomorphism. The second …

Semiparametric Statistical Estimation And Inference With Latent Information, Qianqian Wang

Theses and Dissertations

In Chapter 1, we predicted disease risk by transformation models in the presence of missing subgroup identifiers. When a discrete covariate defining subgroup membership is missing for some of the subjects in a study, the distribution of the outcome follows a mixture distribution of the subgroup-specific distributions. Taking into account the uncertain distribution of the group membership and the covariates, we model the relation between the disease onset time and the covariates through transformation models in each sub-population, and develop a nonparametric maximum likelihood based estimation implemented through EM algorithm along with its inference procedure. We further propose methods to …