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2013

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Full-Text Articles in Physical Sciences and Mathematics

Estimation Of Aerosolized Antibiotic Resistant Bacteria Concentrations From Wastewater Treatment Facilities Using Spatially-Based Dispersion Modeling, Renee Nichole Dickman Jan 2013

Estimation Of Aerosolized Antibiotic Resistant Bacteria Concentrations From Wastewater Treatment Facilities Using Spatially-Based Dispersion Modeling, Renee Nichole Dickman

Theses and Dissertations

Pathogenic bacteria can develop resistance to antibiotics to which they were previously sensitive, resulting in increased morbidity and mortality worldwide [1]. The increase in drug resistance in bacteria is an emerging public health concern. The activated sludge tanks of wastewater treatment plants are known sources of antibiotic resistant bacteria. These resistant bacteria can become aerosolized and disperse downwind. Using previously sampled aerosol concentrations and meteorological data, a Gaussian dispersion model was developed to estimate the concentration downwind from a selected wastewater treatment facility. The emission rate was calculated to be 7,941 CFU/m²/sec ± 2,149 CFU/m²/sec. This value was used in …


Permutation Testing For Covariance Matrices, With Applications In Shape Analysis, Blake Cassidy Hill Jan 2013

Permutation Testing For Covariance Matrices, With Applications In Shape Analysis, Blake Cassidy Hill

Theses and Dissertations

In many applications, it is of interest to compare covariance structures. In this work, we propose hypothesis tests for comparing covariance matrices for data in different groups, especially in shape analysis. The main motivation for the work is comparing covariance matrices of the size and shapes of damaged versus undamaged DNA molecules. A practical motivation behind analyzing the differences between these DNA covariance matrices is to compare the variation between the two groups during situations where the molecules are repairing. The testing methods proposed in this dissertation consist of three types of permutation testing methods for differences in covariance structures. …


Deducing Vertex Weights From Empirical Occupation Times, David Collins Jan 2013

Deducing Vertex Weights From Empirical Occupation Times, David Collins

Theses and Dissertations

We consider the following problem arising from the study of human problem solving: Let $G$ be a vertex-weighted digraph with marked "start" and "end" vertices. Suppose that a random walker begins at the start vertex, steps to neighbors of vertices with probability proportional to their weights, and stops upon reaching the end vertex. Could one deduce the weights from the paths that many such walkers take? We analyze an iterative numerical solution to this reconstruction problem, in particular, given the empirical mean occupation times of the walkers. We then consider the existence of a choice of weights for a given …


The Weierstrass Approximation Theorem, Larita Barnwell Hipp Jan 2013

The Weierstrass Approximation Theorem, Larita Barnwell Hipp

Theses and Dissertations

In this thesis we will consider the work began by Weierstrass in 1855 and several generalization of his approximation theorem since. Weierstrass began by proving the density of algebraic polynomials in the space of continuous real-valued functions on a finite interval in the uniform norm. His theorem has been generalized to an arbitrary compact Hausdorff space and the approximation with elements from more general algebras of continuous real-valued functions. We will consider proofs that use brute force and proofs based on convolutions and approximate identities, trudge through probability and the use of the Bernstein polynomials, and become intimately close to …


Heaped Data In Count Models, Tammy Harris Jan 2013

Heaped Data In Count Models, Tammy Harris

Theses and Dissertations

Heaped data result when subjects who recall the frequency of events prefer for reporting from a limited set of rounded responses or preferred digits over reporting exact counts. These rounded responses and digit preferences (also referred to as data coarsening) could be characterized by reported frequencies (or counts) favoring multiples of 20, reporting counts ending with 0 or 5, or a preference for reporting an even number over an odd number or vice versa. This mixture of values is a type of measurement error (pattern of misreporting) that can lead to biased estimation and imprecision in discrete quantitative data. Sometimes …


Models And Software Development For Interval-Censored Data, Chun Pan Jan 2013

Models And Software Development For Interval-Censored Data, Chun Pan

Theses and Dissertations

Interval-censored time-to-event data occur naturally in studies of diseases where the symptoms are not directly observable, and periodic clinical examinations are required for detection. Due to the lack of well-established procedures, interval-censored data have been conventionally treated as right-censored data, however, this introduces bias at the first place. This dissertation focuses on methodological research and software development for interval-censored data. Specifically, it consists of three projects. The first project is to create an R package for regression analysis and survival curve estimation of interval-censored data based on several published papers by our research team. In the second project, a Bayesian …


Volcanic And Tectonic Processes Along Anomalous Mid-Ocean Ridges, Julia Kathryn Howell Jan 2013

Volcanic And Tectonic Processes Along Anomalous Mid-Ocean Ridges, Julia Kathryn Howell

Theses and Dissertations

The morphological and structural characteristics of the global spreading ridge system are systematically related to spreading rate and magma supply (e.g. Macdonald, 1982). Because intermediate spreading-rate ridges (ISRs) spreading between 60 and 80 mm/yr have characteristics of both fast and slow spreading ridges, they are ideal environments to study the differences controlling upper crustal accretion. We examine the distribution of seamounts along spreading ridges to understand the relationship between seamount volcanism and axial morphology along four ISRs: the Juan de Fuca Ridge (JdFR), the Galápagos Spreading Centers (GSC), the Southeast Indian Ridge (SEIR), and the Eastern Lau Spreading Centers (ELSC). …


Benthic Boundary Layer Processes: Bedform Evolution And Bottom Turbulence, Timothy Robert Nelson Jan 2013

Benthic Boundary Layer Processes: Bedform Evolution And Bottom Turbulence, Timothy Robert Nelson

Theses and Dissertations

Bedform roughness, caused by ripples on the seabed, plays an important role in controlling sediment dynamics in the nearshore region. In this dissertation, the temporal and spatial evolution of ripples from two field sites located in the South Atlantic Bight, offshore Long Bay, SC and Georgia are used to relate wave-induced ripple geometry (wavelength and orientation) to near bed directional wave velocities. 2-D spectral analysis techniques were developed to automate detection of ripple wavelength, direction, and irregularity. This analysis showed that magnitude, direction, and duration of wave forcing controls ripple geometry and irregularity. During highly energetic events, ripple geometry changes …


Drought Indices In Decision-Making Process Of Drought Management, Ekaterina Negodyaeva Altman Jan 2013

Drought Indices In Decision-Making Process Of Drought Management, Ekaterina Negodyaeva Altman

Theses and Dissertations

Drought indices are one of the most important elements of an effective drought monitoring and early warning system. They help to characterize drought and guide appropriate responses to reduce drought impacts. Drought indicators are more useful than raw data in decision-making process, even though each index has specific use and limited by its strengths and weaknesses. The literature review showed the evaluation of drought conditions by decision-makers as an important issue, but so far no research has been done to understand how decision-makers use diverse and often conflicting values of drought indices to make drought declarations. This research studies how …


Climate Change Effects On Vibrio Bacteria In The Winyah Bay Estuary And The Projected Spread Of Vibrio Under Future Climatic Scenarios., Reem Deeb Jan 2013

Climate Change Effects On Vibrio Bacteria In The Winyah Bay Estuary And The Projected Spread Of Vibrio Under Future Climatic Scenarios., Reem Deeb

Theses and Dissertations

While there are several studies on the distribution ofVibrio vulnificusandVibrio parahaemolyticusin estuarine waters around the world, there is little information on the distribution of both organisms in South Carolina waters. Monthly sampling of surface and bottom water from 9 sites in Winyah Bay was conducted over the period April-October 2012. Both organisms were enumerated on CHROMagarVibriomedia. TheVibriocounts obtained were mainly less than 20 Colony Forming Units (CFU)/ml which is typical for what was found elsewhere along the coast of the Carolinas. TheVibrio vulnificuscounts were the highest when salinity ranged between 5 ppt and 20 ppt.Vibrio parahaemolyticusdid not show a clear …


Energy Metrics For State Government Buildings, Trevor Michael Jan 2013

Energy Metrics For State Government Buildings, Trevor Michael

Theses and Dissertations

Measuring true progress towards energy conservation goals requires the accurate reporting and accounting of energy consumption. An accurate energy metrics framework is also a critical element for verifiable Greenhouse Gas Inventories. Energy conservation in government can reduce expenditures on energy costs leaving more funds available for public services. In addition to monetary savings, conserving energy can help to promote energy security, air quality, and a reduction of carbon footprint. With energy consumption/GHG inventories recently produced at the Federal level, state and local governments are beginning to also produce their own energy metrics systems.

In recent years, many states have passed …


Accelprint:Accelerometers Are Different By Birth, Sanorita Dey Jan 2013

Accelprint:Accelerometers Are Different By Birth, Sanorita Dey

Theses and Dissertations

This paper submits a hypothesis that smartphone accelerometers possess unique fingerprints. We believe that the fingerprints arise from hardware imperfections during the sensor manufacturing process, causing every sensor chip to respond differently to the same motion stimulus. The differences in responses are subtle enough that they do not affect most of the higher level functions computed on them. Nonetheless, upon close inspection, these fingerprints emerge with consistency, and can even be somewhat independent of the stimulus that generates them. Measurements and classification on 80 standalone accelerometer chips, 25 Android phones, and 2 tablets, show precision and recall upward of 96%, …


3d Grain Segmentation In Superalloy Images Using Multichannel Edge-Weighted Centroidal Voronoi Tessellation Based Methods, Yu Cao Jan 2013

3d Grain Segmentation In Superalloy Images Using Multichannel Edge-Weighted Centroidal Voronoi Tessellation Based Methods, Yu Cao

Theses and Dissertations

Accurate grain segmentation on 3D superalloy images is very important in materials science and engineering. From grain segmentation, we can derive the underlying superalloy grains' micro-structures, based on which many important physical, mechanical and chemical properties of the superalloy samples can be evaluated. However, grain segmentation is usually a very challenging problem since: 1) even a small 3D superalloy sample may contain hundreds of grains; 2) carbides and noises may degrade the imaging quality; and 3) the intensity within a grain may not be homogeneous. In addition, the same grain may present different appearances, i.e. intensities, under different microscope settings. …


Accelerating Short Read Mapping Using A Dsp Based Coprocessor, Shaun I. Gause Jan 2013

Accelerating Short Read Mapping Using A Dsp Based Coprocessor, Shaun I. Gause

Theses and Dissertations

Advances in next generation sequencing technologies have allowed short reads to be generated at an increasing rate, shifting the bottleneck of the sequencing process to the short read mapping computations. High costs and extended processing times drive researchers to pursue more efficient solutions with an overall goal of a short read mapping architecture capable of processing short reads as they are generated. Digital signal processors have shown high performance capabilities while maintaining low power consumption in a wide field of applications. This thesis explores the use of a DSP accelerated exact match short read mapping algorithm, focusing on a performance …


Multi-Label Segmentation Propagation For Materials Science Images Incorporating Topology And Interactivity, Jarrell Waggoner Jan 2013

Multi-Label Segmentation Propagation For Materials Science Images Incorporating Topology And Interactivity, Jarrell Waggoner

Theses and Dissertations

Segmentation propagation is the problem of transferring the segmentation of an image to a neighboring image in a sequence. This problem is of particular importance to materials science, where the accurate segmentation of a series of 2D serial-sectioned images of multiple, contiguous 3D structures has important applications. Such structures may have prior-known shape, appearance, and/or topology among the underlying structures which can be considered to improve segmentation accuracy. For example, some materials images may have structures with a specific shape or appearance in each serial section slice, which only changes minimally from slice to slice; and some materials may exhibit …


Characterization Of The Role Of Fro6 In Metal Homeostasis In Arabidopsis Thaliana, Margo Ellen Maynes Jan 2013

Characterization Of The Role Of Fro6 In Metal Homeostasis In Arabidopsis Thaliana, Margo Ellen Maynes

Theses and Dissertations

Iron deficiency is the most common human nutritional disorder in the world today, affecting approximately 2 billon people worldwide, almost a third of the world's population. For most of the world's population, plant foods serve as the major source of dietary iron. One approach that may contribute towards the solution of iron deficiency is the development of crop plants that contain higher levels of bioavailable iron. This project focuses on FRO6, a ferric chelate reductase in Arabidopsis thaliana that is thought to reduce apoplastic iron for transport across the plasma membrane in leaf cells. We hypothesize therefore that FRO6 controls …


Trophic Response To Polycyclic Aromatic Hydrocarbons And Copper In Tidal Flats Of North Inlet, South Carolina, Leslie Lynn Muggelberg Jan 2013

Trophic Response To Polycyclic Aromatic Hydrocarbons And Copper In Tidal Flats Of North Inlet, South Carolina, Leslie Lynn Muggelberg

Theses and Dissertations

The trophic link between benthic microalgae (BMA) and fiddler crabs is critical for the ecosystem functioning of estuaries and alterations in this linkage by anthropogenic activities could have cascading impacts on food webs and biogeochemical cycling in these sensitive habitats. Singular and interactive effects of two common pollutants in aquatic ecosystems, polycyclic aromatic hydrocarbons (PAHs) and copper (Cu), were investigated by exposing field collected sediment communities to the contaminants and measuring changes in BMA biomass and community composition in a bioassay design. The consequential impacts on the food web were then explored by examining the effects of PAHs and copper …


Environmental Pre-Conditioning Of Bacterial Populations And Communities To Extreme Acidity, Gabriel Joseph Swenson Jan 2013

Environmental Pre-Conditioning Of Bacterial Populations And Communities To Extreme Acidity, Gabriel Joseph Swenson

Theses and Dissertations

The ability of opportunistic enteric pathogens to cause disease is effected by their ability to survive the variable and lethal acidity of the mammalian host gastrointestinal milieu. In many of these pathogens, survival is conferred by an acid stress response (ASR). ASR is elicited when bacterial cells are pre-conditioned in sub-lethal acidity (pH 4-6) which induces rapid biochemical and physiological modifications and facilitates survival when extreme acidity (pH 1-3) is encountered. In Vibrio cholerae, the causative agent of the diarrheal disease Cholera, ASR was initially investigated in an effort to determine how this ubiquitous aquatic bacterium is capable of causing …


The Scope Of The Bis-Urea Macrocycle Assembly Motif, Michael F. Geer Jan 2013

The Scope Of The Bis-Urea Macrocycle Assembly Motif, Michael F. Geer

Theses and Dissertations

From the formation of rock candy crystals, to the functionality of DNA in the cell, to the cosmic dust throughout the universe, supramolecular chemistry has a great impact and importance in the world around us. In this thesis, we explore the supramolecular interactions and self-assembly of bis¬-urea macrocyclic systems and investigate how their structure and assembly influences bulk properties and functionality. Specifically, in chapter one, we review the factors that guide, limit, and define supramolecular structures from the atomic to the centimeter scale.

In chapter two, we investigate the incorporation of benzophenone, a well known triplet sensitizer, within a bis-urea …


Design And Synthesis Of Polymer-Based Advanced Nanomaterials Using Raft Polymerization And Click Reaction, Junting Li Jan 2013

Design And Synthesis Of Polymer-Based Advanced Nanomaterials Using Raft Polymerization And Click Reaction, Junting Li

Theses and Dissertations

This research focuses on exploring new synthetic approaches to prepare polymer-based advanced nanomaterials using highly efficient chemical tools, such as reversible addition-fragmentation chain transfer (RAFT) polymerization and click reactions.

In the first project, novel synthetic routes to produce fullerene-based polymers were designed. First, mono-alkynyl functionalized fullerene was prepared starting with pristine fullerene (C60). Methyl methacrylate and 6-azido hexyl methacrylate were then randomly copolymerized via RAFT polymerization with well-controlled molecular weights and copolymer compositions. Finally, the two moieties were covalently assembled into a series of well-defined side-chain fullerene polymers (SFP's) via the copper-catalyzed click reaction. The TGA and UV-vis …


Thermal Infrared Imaging: Instrumentation And Method Development, Wayne O'Brien Jan 2013

Thermal Infrared Imaging: Instrumentation And Method Development, Wayne O'Brien

Theses and Dissertations

A recently development thermal infrared camera system was improved by designing new components to downsize physical aspect and improve the instrument's performance. A new thermal infrared light source was developed and characterized. It is designed from a custom-made Macor backpiece that holds an alumina screw. High resistance wire is coiled around the screw. The coiled wire is covered with an alumina coating. Most light sources have a spectral emissivity similar to that of a blackbody emitter. This source has a spectral irradiance profile that is not similar to a blackbody source. Thus, the lamp has an improved efficiency in the …


Single Crystal To Single Crystal Polymerization Of A Columnar Assembled Diacetylene Macrocycle, Weiwei Xu Jan 2013

Single Crystal To Single Crystal Polymerization Of A Columnar Assembled Diacetylene Macrocycle, Weiwei Xu

Theses and Dissertations

Organic tubular materials have attracted lots of attentions for their potential applications as nanoscale fluidic transport systems, specific ion sensors, molecular sieves and confined molecular reaction containers. While conjugated polymers, due to delocalized Pi electrons, exhibit interesting solar cells and sensors applications. In this thesis, we developed a conjugated polymer which combines the attributes of conjugated polymers with tubular materials, which should have great potential to work as a sensing material.

We reproduced and scaled-up the synthesis of a polymerizable macrocycle 1 that contains two rigidly separated diacetylene units. We found that, through hydrogen bonding, 1 can assemble into columnar …


Instrument And Method Development For Single-Cell Classification Using Fluorescence Imaging Multivariate Optical Computing, Joseph Swanstrom Jan 2013

Instrument And Method Development For Single-Cell Classification Using Fluorescence Imaging Multivariate Optical Computing, Joseph Swanstrom

Theses and Dissertations

Multivariate optical computing (MOC) is an all-optical approach of predictive spectroscopy that utilizes multivariate calibration and spectral pattern recognition techniques while operating in a simple filter photometer instrument, removing the need for expensive instrumentation and post-processing of spectral data. This is accomplished with specially designed interference filters called multivariate optical elements (MOEs). MOC can provide analytical solutions for applications requiring low cost, rugged, and simple to operate instrumentation for use in remote and hazardous environments such as open ocean waters. These instrument specifications are central for developing a method for classifying phytoplankton in their natural environment. Phytoplankton are photosynthetic single …


Iridium-Ruthenium/Osmium-Gold Cluster Complexes: Unique Structures And Properties, Qiang Zhang Jan 2013

Iridium-Ruthenium/Osmium-Gold Cluster Complexes: Unique Structures And Properties, Qiang Zhang

Theses and Dissertations

Chapter Two

The first Ir-Ru cluster complex was synthesized was the electron-rich, anionic, planar cluster complex [PPN][IrRu6(CO)23], 2.5, (PPN=Bis(triphenylphophoranylidene)-ammonium) which obtained from the reaction of [PPN][IrRu3(CO)13] with one equivalent ruthenium carbonyl (Ru3(CO)12) at 66 oC (THF reflux) for 12h. Compound 2.5 could also be synthesized by using the mono-Iridium compound [PPN][Ir(CO)4] reacts with two equivalent of ruthenium carbonyl. In compound 2.5, all seven metal atoms lie in a plane (max deviation = 0.043(1) Å) with the iridium atom in the center circumscribed by a hexagonal ring of six ruthenium atoms. The anion 2.5 contains 104 valence electrons while both the …


Silylation-Based Kinetic Resolution Of Α-Hydroxy Carbonyl Compounds And Synthesis Of Chiral Isothiourea Catalysts, Yan Zhang Jan 2013

Silylation-Based Kinetic Resolution Of Α-Hydroxy Carbonyl Compounds And Synthesis Of Chiral Isothiourea Catalysts, Yan Zhang

Theses and Dissertations

The thesis describes the silylation-based kinetic resolution for α-hydroxy carbonyl compounds catalyzed by isothiourea catalyst as well as our effort to make novel chiral isothiourea catalyst.

In Chapter 1, general background will be introduced, including chirality, general methods to obtain enantiopure compounds and kinetic resolution. In Chapter 2, the mechanism of the chiral recognition was discussed and a novel isothiourea catalyst was design to investigate the mechanism. The synthesis of the new catalyst was also described in this chapter.

In Chapter 3, the silylation-based kinetic resolution for α-hydroxy carbonyl compounds will be discussed. Since silylation-based kinetic resolution have already been …


Selected Research In Covering Systems Of The Integers And The Factorization Of Polynomials, Joshua Harrington Jan 2013

Selected Research In Covering Systems Of The Integers And The Factorization Of Polynomials, Joshua Harrington

Theses and Dissertations

In 1960, Sierpi\'{n}ski proved that there exist infinitely many odd positive integers $k$ such that $k\cdot 2^n+1$ is composite for all positive integers $n$. Such integers are known as Sierpi\'{n}ski numbers. Letting $f(x)=ax^r+bx+c\in\mathbb{Z}[x]$, Chapter 2 of this document explores the existence of integers $k$ such that $f(k)2^n+d$ is composite for all positive integers $n$. Chapter 3 then looks into a polynomial variation of a similar question. In particular, Chapter~\ref{CH:FH} addresses the question, for what integers $d$ does there exist a polynomial $f(x)\in\mathbb{Z}[x]$ with $f(1)\neq -d$ such that $f(x)x^n+d$ is reducible for all positive integers $n$. The last two chapters of …


Shimura Images Of A Family Of Half-Integral Weight Modular Forms, Kenneth Allan Brown Jan 2013

Shimura Images Of A Family Of Half-Integral Weight Modular Forms, Kenneth Allan Brown

Theses and Dissertations

In 1973, Shimura introduced a family of maps between modular forms of half-integral weight and modular forms of even integral weight. We will give explicit formulas for the images of two different classes of modular forms under these maps. In contrast to Shimura's difficult analytic construction, our formulas will fall out of relatively simple combinatorial derivations. Using the Shimura correspondence, we will prove congruences for the eigenvalues of a family of eigenforms introduced by Garvan. Using deep results of Eichler and Shimura, we state these congruences in terms of the number of points on associated elliptic curves, and we provide …


Study Of Porous, Crystalline Supramolecular Boronates, Vincenzo Michael Disantis Jan 2013

Study Of Porous, Crystalline Supramolecular Boronates, Vincenzo Michael Disantis

Theses and Dissertations

Porous materials with the ability to selectively absorb volatile organic compounds are of high interest for applications in sensing, sequestration and separations. Utilizing the covalent yet reversible boronate ester bonds between boronic acids and diols in conjunction with dative boron-nitrogen coordination bonds has allowed for the discovery of a new class of porous materials. Preliminary results show the ability to obtain porous, crystalline supramolecular boronate networks from the coordination of diamine linkers with boronate diester backbones. Further exploration of porous, crystalline supramolecular boronates has revealed the discovery of a porous crystalline coordination polymer that exhibits reversible, selective guest adsorption properties …


Thermal History Of Nearly Metamict Zircon Of The Taza-Guercif Basin (Morocco) Revealed Using Scanning Electron Microscope High-Density Fission-Track Dating, Tyler Michael Izykowski Jan 2013

Thermal History Of Nearly Metamict Zircon Of The Taza-Guercif Basin (Morocco) Revealed Using Scanning Electron Microscope High-Density Fission-Track Dating, Tyler Michael Izykowski

Theses and Dissertations

Northwest Africa provides unique insight into a wide range of geologic processes throughout a vast portion of Earth's history. Moroccan geology in particular can provide valuable insight, from the formations of West Africa through the Eburnian orogeny (~2000 Ma), Gondwana during the Pan-African orogeny (~900-500 Ma), and Pangaea by means of the Hercynian (Variscan) orogeny (~400-300 Ma), to more recent crustal and climatic events, such as the Messinian salinity crisis (5.96-5.33 Ma). However, the current lack of western literature regarding this region presents a significant obstacle in understanding the aforementioned processes. Herein, I employ a new technique in zircon fission-track …


The Effects Of Mean Sea Level And Tidal Amplitude On Ground Water Discharge And Pore-Water Salinity Distribution Along A Forest/Marsh Boundary, North Inlet, Sc, John Bradley Peurifoy Jan 2013

The Effects Of Mean Sea Level And Tidal Amplitude On Ground Water Discharge And Pore-Water Salinity Distribution Along A Forest/Marsh Boundary, North Inlet, Sc, John Bradley Peurifoy

Theses and Dissertations

Advective groundwater flow in salt marshes is an important mechanism through which nutrients are exported to adjacent coastal waters. Groundwater flow also influences the distribution of pore-water salinity in the subsurface marsh, which affects botanical zonation, nutrient transport, and primary productivity. Recent idealized marsh island simulations have suggested that increases in tidal amplitude result in increased groundwater discharge, and that the elevation of MWL relative to the marsh platform is inversely related to groundwater discharge. These simulations were only representative of marsh islands (as opposed to forest-marsh boundaries) and relied on simulated tides and MWL position. The results were not …