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Articles 3361 - 3390 of 4194

Full-Text Articles in Physical Sciences and Mathematics

A Computational Chemistry Study Of Spin Traps., Jacob Fosso-Tande Aug 2007

A Computational Chemistry Study Of Spin Traps., Jacob Fosso-Tande

Electronic Theses and Dissertations

Many defects in physiological processes are due to free radical damage: reactive oxygen species, nitric oxide, and hydroxyl radicals have been implicated in the parthenogenesis of cancer, diabetes mellitus, and rheumatoid arthritis. We herein characterize the phenyl-N-ter-butyl nitrone (PBN) type spin traps in conjunction with the most studied dimethyl-1-pyrroline-N-oxide (DMPO) type spin traps using the hydroxyl radical. In this study, theoretical calculations are carried out on the two main types of spin traps (DMPO and PBN) at the density functional theory level (DFT). The energies of the optimized structures, hyperfine calculations in gaseous and aqueous phases of the spin traps …


Risk Assessment For Hazardous Materials Incident, Washington County, Tennessee: Road Transportation, Rail Transportation, And Hazardous Materials Storage., Steed Kenlee Stagnolia Aug 2007

Risk Assessment For Hazardous Materials Incident, Washington County, Tennessee: Road Transportation, Rail Transportation, And Hazardous Materials Storage., Steed Kenlee Stagnolia

Electronic Theses and Dissertations

This study was conducted to provide a quantitative risk assessment for road transportation, railway transportation, and storage of hazardous materials in Washington County, Tennessee. A roadside survey, railroad hazardous materials survey, and a chemical inventory were conducted. It revealed an estimated 267,858 HAZMAT shipments per year on primary and secondary roadways and an estimated total of 9.4 x 109 tons of HAZMAT shipped by rail per year. There are 49 facilities that store a daily average of 33,722,700 lbs of HAZMAT. The risk of a hazardous materials incident occurring in Washington County is highest for Interstate transportation. The risk for …


Beverage Consumption And Hypertension: Findings From The Third National Health And Nutrition Examination Survey., Vishal Arunbhai Mandge Aug 2007

Beverage Consumption And Hypertension: Findings From The Third National Health And Nutrition Examination Survey., Vishal Arunbhai Mandge

Electronic Theses and Dissertations

The study sample was comprised of 18,953 subjects aged 18 years and older who participated in the Third National Health and Nutrition Examination Survey. Preference for diet soda over regular soda was higher in females as compared to males and in Caucasians as compared to other races. Mean alcohol consumption was almost three times higher in males than in females. Undiagnosed hypertension was more common in males than in females, in 65-90 than in 50-64 year olds, and in people with less than high school education compared to those with higher education. Diastolic pressure was correlated with the level of …


Decompositions, Packings, And Coverings Of Complete Directed Gaphs With A 3-Circuit And A Pendent Arc., Chrys Gwellem Aug 2007

Decompositions, Packings, And Coverings Of Complete Directed Gaphs With A 3-Circuit And A Pendent Arc., Chrys Gwellem

Electronic Theses and Dissertations

In the study of Graph theory, there are eight orientations of the complete graph on three vertices with a pendant edge, K3 ∪ {e}. Two of these are the 3-circuit with a pendant arc and the other six are transitive triples with a pendant arc. Necessary and sufficient conditions are given for decompositions, packings, and coverings of the complete digraph with the two 3-circuit with a pendant arc orientations.


Pleistocene Peccaries From Guy Wilson Cave, Sullivan County, Tennessee., April Season Nye Aug 2007

Pleistocene Peccaries From Guy Wilson Cave, Sullivan County, Tennessee., April Season Nye

Electronic Theses and Dissertations

Descriptive and taphonomic analyses of undescribed Pleistocene Tayassuidae from Guy Wilson Cave within the East Tennessee State University and McClung Museum collections revealed a MNI of 16 Platygonus compressus and 2 Mylohyus from left femora and isolated teeth, respectively. Linkage between upper dentition and species identification is suggested by comparing Mylohyus fossilis to M. nasutus from other Pleistocene-aged sites. Long-bone NISP and age profiles show a predominance of Platygonus adults. Tayassuidae upper canines, likely Platygonus, suggest sexual dimorphism. Long bones were analyzed for carnivore damage and utilization revealing light utilization similar to that caused by modern wolves. Long bone …


Assessment Of The Flame Angelfish (Centropyge Loriculus) As A Model Species In Studies On Egg And Larval Quality In Marine Fishes, Chatham K. Callan Aug 2007

Assessment Of The Flame Angelfish (Centropyge Loriculus) As A Model Species In Studies On Egg And Larval Quality In Marine Fishes, Chatham K. Callan

Electronic Theses and Dissertations

This project sought to determine if flame angelfish (Centropyge loriculus) could serve as models in examination of environmental and dietary effects on egg quality in marine fishes. Evaluation of 21 marine ornamental species identified flame angelfish as being amenable to egg quality research, due to their rapid conditioning and frequency of spawning. At the onset of this project, accidental copper introduction to broodstock systems required assays to determine the effects of copper exposure on survival and reproduction. Flame angelfish exhibited accute sensitivity to copper, as 60% of fish exposed to 0.25mg/L died within 12 hours of exposure. Likewise, fish exposed …


Economic Approaches To Public And Private Land Conservation In The United States, Amy Claire Hudnor Aug 2007

Economic Approaches To Public And Private Land Conservation In The United States, Amy Claire Hudnor

Electronic Theses and Dissertations

This research is composed of two essays, both using economic approaches to evaluate land conservation in the United States. Essay I uses econometric methods to evaluate public lands, and Essay II uses New Institutional Economics to gain insight into private land conservation. Essay I is titled "The Relationship Between Public Conservation Lands and Tourism Employment in the United States." This research examines the relationship between public conservation lands and the importance of tourism in United States counties. A spatial error model is used on three categories of conservation land: general public land, recreational land, and wilderness areas. A positive, significant …


Alliance Partitions In Graphs., Jason Lachniet May 2007

Alliance Partitions In Graphs., Jason Lachniet

Electronic Theses and Dissertations

For a graph G=(V,E), a nonempty subset S contained in V is called a defensive alliance if for each v in S, there are at least as many vertices from the closed neighborhood of v in S as in V-S. If there are strictly more vertices from the closed neighborhood of v in S as in V-S, then S is a strong defensive alliance. A (strong) defensive alliance is called global if it is also a dominating set of G. The alliance partition number (respectively, strong …


Epidemic Of Lung Cancer Or Artifact Of Classification In The State Of Kentucky?, Beatrice Simo May 2007

Epidemic Of Lung Cancer Or Artifact Of Classification In The State Of Kentucky?, Beatrice Simo

Electronic Theses and Dissertations

Lung cancer remains the leading cause of cancer deaths in the United States despite public health campaigns aimed at reducing its rate of mortality. Kentucky is the state with the highest lung cancer incidence and mortality. This study aims to assess the impact of misclassification of cause of death from Lung Cancer in Kentucky for the period 1979 to 2002. We will examine the potential competing classification of death for two other smoking-related diseases, Chronic Obstructive Pulmonary Disease (COPD) and Emphysema. Age-adjusted mortality rates for these diseases for white males were obtained from the National Center for Health Statistics. There …


Factors That Affect The Global Positioning System And Global Navigation Satellite System In An Urban And Forested Environment., Douglas Allen Ritchie May 2007

Factors That Affect The Global Positioning System And Global Navigation Satellite System In An Urban And Forested Environment., Douglas Allen Ritchie

Electronic Theses and Dissertations

The purpose of this study was to evaluate the accuracy in real time measurements acquired from GPS and GLONASS satellite observations using RTK techniques in an urban and forested environment. To determine this accuracy, 2 data sets of 3-dimensional coordinates were created and compared at 14 stations situated at East Tennessee State University. One data set included coordinates determined by conventional land survey methods; the second was solved by RTK GPS/GLONASS. Once the magnitude of any deviation in the coordinate positions was determined, the contributions to the accuracies from cycle slips, multipath, satellite availability, PDOP, and fixed or float solutions …


Arrow Symbols: Theory For Interpretation, Yohei Kurata May 2007

Arrow Symbols: Theory For Interpretation, Yohei Kurata

Electronic Theses and Dissertations

People often sketch diagrams when they communicate successfully among each other. Such an intuitive collaboration would also be possible with computers if the machines understood the meanings of the sketches. Arrow symbols are a frequent ingredient of such sketched diagrams. Due to the arrows’ versatility, however, it remains a challenging problem to make computers distinguish the various semantic roles of arrow symbols. The solution to this problem is highly desirable for more effective and user-friendly pen-based systems. This thesis, therefore, develops an algorithm for deducing the semantic roles of arrow symbols, called the arrow semantic interpreter (ASI). The …


Remote Assessment Of 4-D Phytoplankton Distributions Off The Washington Coast, Brandon S. Sackmann May 2007

Remote Assessment Of 4-D Phytoplankton Distributions Off The Washington Coast, Brandon S. Sackmann

Electronic Theses and Dissertations

Satellite-based optical measurements were coupled with physical and optical measurements from Seaglider – a long-range autonomous glider – to study interactions between biological and physical processes off the coast of Washington, USA, and to evaluate space-time variability of regional phytoplankton and particle distributions. Using satellite ocean color data variability in near-surface chlorophyll a was characterized across a range of spatial and temporal scales ranging from 1 – 500 km and from days – years to assess region-wide responses by phytoplankton to changes in environmental conditions. Results from 1998 – 2002 revealed both strong negative and positive anomalies associated with lingering …


Modification Of Semi-Metal Oxide And Metal Oxide Powders By Atomic Layer Deposition Of Thin Films, Mark Q. Snyder May 2007

Modification Of Semi-Metal Oxide And Metal Oxide Powders By Atomic Layer Deposition Of Thin Films, Mark Q. Snyder

Electronic Theses and Dissertations

This work describes two methods of modifying, and the subsequent characterizing of, oxide nanopowders. The first method, atomic layer deposition, or ALD, is a series of surface-limited reactions that are repeated to deposit a thin, inorganic film on the surface of the nanopowder. Deposition of a thin film is a useful method to alter the surface properties of a material while retaining its bulk properties. Part of this thesis concerns the understanding of the growth mechanism of thin film titanium nitride (a material known for thermal and chemical stability as well as electronic conductivity) on silica through the ALD process. …


Myriophyllum Heterophyllum Michx. (Haloragaceae): Control And Vegetative Reproduction In Southwestern Maine, Jacolyn E. Bailey May 2007

Myriophyllum Heterophyllum Michx. (Haloragaceae): Control And Vegetative Reproduction In Southwestern Maine, Jacolyn E. Bailey

Electronic Theses and Dissertations

Native to the southeastern United States, variable-leaf watermilfoil (Myriophyllum heterophyllum) is an invasive species in the Northeast and has been documented in Maine lakes for twenty years. Variable-leaf watermilfoil is targeted by the Maine Department of Environmental Protection as a species of grave concern as it has aggressively colonized twenty-six water bodies in Maine. This aquatic invasive plant grows in dense mats and outcompetes native vegetation. It is causing both ecological and economic disruption to Maine's lakes and ponds. The plants clog boat motors and deter people from swimming and other water related activities. Allofragmentation and autofragmentation occur …


Kinetics And Mechanism Of Oxygen Delignification, Yun Ji May 2007

Kinetics And Mechanism Of Oxygen Delignification, Yun Ji

Electronic Theses and Dissertations

Considerable research has been conducted into the kinetics and selectivity of the oxygen delignification process to overcome limitation in its use. However most studies were performed in a batch reactor whereby the hydroxide and dissolved oxygen concentrations are changing during the reaction time in an effort to simulate tower performance in pulp mills. This makes it difficult to determine the reaction order of the different reactants in the rate expressions. Also the lignin content and cellulose degradation of the pulp are only established at the end of the experiment when the sample is removed from the batch reactor. To overcome …


Physically-Based Visualization Of Residential Building Damage Process In Hurricane, Dezhi Liao Jan 2007

Physically-Based Visualization Of Residential Building Damage Process In Hurricane, Dezhi Liao

Electronic Theses and Dissertations

This research provides realistic techniques to visualize the process of damage to residential building caused by hurricane force winds. Three methods are implemented to make the visualization useful for educating the public about mitigation measures for their homes. First, the underline physics uses Quick Collision Response Calculation. This is an iterative method, which can tune the accuracy and the performance to calculate collision response between building components. Secondly, the damage process is designed as a Time-scalable Process. By attaching a damage time tag for each building component, the visualization process is treated as a geometry animation allowing users to navigate …


A Novel Setup For High-Pressure Raman Spectroscopy Under A Microscope, Thomas Andrew Oakeson Jan 2007

A Novel Setup For High-Pressure Raman Spectroscopy Under A Microscope, Thomas Andrew Oakeson

Electronic Theses and Dissertations

Functional properties of biological molecules and cells are affected by environmental parameters such as temperature and pressure. While Raman spectroscopy provides an intrinsic probe of molecular structural changes, the incorporation of a microscope enables studies of minuscule amounts of biological compounds with spatial resolution on a micron scale. We have developed a novel setup which combines a Raman microscope and a high pressure cell. A micro-capillary made out of fused silica simultaneously serves as the supporting body and the optical window of the pressure cell. The cell has been tested over the pressure range from 0.1 to 4 kbar. Raman …


The Response Of A General Circulation Climate Model Tohigh Latitude Freshwater Forcing In The Atlantic Basinwith Respect Totropi, Victor Paulis Jan 2007

The Response Of A General Circulation Climate Model Tohigh Latitude Freshwater Forcing In The Atlantic Basinwith Respect Totropi, Victor Paulis

Electronic Theses and Dissertations

The current cycle of climate change along with increases in hurricane activity, changing precipitation patterns, glacial melt, and other extremes of weather has led to interest and research into the global correlation or teleconnection between these events. Examination of historical climate records, proxies and observations is leading to formulation of hypotheses of climate dynamics with modeling and simulation being used to test these hypotheses as well as making projections. Ocean currents are believed to be an important factor in climate change with thermohaline circulation (THC) fluctuations being implicated in past cycles of abrupt change. Freshwater water discharge into high-latitude oceans …


Synthesis Of Novel Aziridine Derivatives Of Podocarpic Acid, Stephen Rhoden Jan 2007

Synthesis Of Novel Aziridine Derivatives Of Podocarpic Acid, Stephen Rhoden

Electronic Theses and Dissertations

Podocarpic acid (a diterpenoid resin acid extracted from the Podocarpacea specie of plants) has shown cytotoxicity against carcinoma of the nasopharynx. Since this discovery has been made, research has been performed in order to alter the structure of the resin acid so as to increase the anticancer activity. The carboxylic acid and phenol functional groups, which are present in podocarpic acid, make it possible to synthesize new derivatives selectively at the C-15, C-13, and C-7 positions as well as by substitution of the phenol hydroxyl group. Thus numerous derivatives can be prepared, in high yield, for the purpose of investigating …


Behavior Of Variable-Length Genetic Algorithms Under Random Selection, Harold Stringer Jan 2007

Behavior Of Variable-Length Genetic Algorithms Under Random Selection, Harold Stringer

Electronic Theses and Dissertations

In this work, we show how a variable-length genetic algorithm naturally evolves populations whose mean chromosome length grows shorter over time. A reduction in chromosome length occurs when selection is absent from the GA. Specifically, we divide the mating space into five distinct areas and provide a probabilistic and empirical analysis of the ability of matings in each area to produce children whose size is shorter than the parent generation's average size. Diversity of size within a GA's population is shown to be a necessary condition for a reduction in mean chromosome length to take place. We show how a …


Nonlinear Optical Properties Of Organic Chromophores Calculated Within Time Dependent Density Functional Theory, Sergio Tafur Jan 2007

Nonlinear Optical Properties Of Organic Chromophores Calculated Within Time Dependent Density Functional Theory, Sergio Tafur

Electronic Theses and Dissertations

Time Dependent Density Functional Theory offers a good accuracy/computational cost ratio among different methods used to predict the electronic structure for molecules of practical interest. The Coupled Electronic Oscillator (CEO) formalism was recently shown to accurately predict Nonlinear Optical (NLO) properties of organic chromophores when combined with Time Dependent Density Functional Theory. Unfortunately, CEO does not lend itself easily to interpretation of the structure activity relationships of chromophores. On the other hand, the Sum Over States formalism in combination with semiempirical wavefunction methods has been used in the past for the design of simplified essential states models. These models can …


Analytical Evaluation Of The Fluorescence Characteristics Of Metabolites Of Polycyclic Aromatic Hydrocarbons At Room, Liquid Nitrogen And Liquid Helium Temperatures, Keerthika Vatsavai Jan 2007

Analytical Evaluation Of The Fluorescence Characteristics Of Metabolites Of Polycyclic Aromatic Hydrocarbons At Room, Liquid Nitrogen And Liquid Helium Temperatures, Keerthika Vatsavai

Electronic Theses and Dissertations

Although environmental monitoring of polycyclic aromatic hydrocarbons (PAH) is an essential step to prevent human exposure to contaminated sites, it provides little information on the actual human uptake and subsequent risks. To this end, urine analysis of short-term biomarkers such as PAH metabolites fill an important niche. The general approach follows the sequence of urine hydrolysis, sample clean-up and pre-concentration, chromatographic separation and determination. Whereas chromatographic methods are based on well established laboratory techniques, the development of easy-to-use, cost-effective and large sample throughput techniques is becoming increasingly relevant to investigate adverse PAH effects on large human populations. This thesis compares …


Advances In Fire Debris Analysis, Mary Williams Jan 2007

Advances In Fire Debris Analysis, Mary Williams

Electronic Theses and Dissertations

Fire incidents are a major contributor to the number of deaths and property losses within the United States each year. Fire investigations determine the cause of the fire resulting in an assignment of responsibility. Current methods of fire debris analysis are reviewed including the preservation, extraction, detection and characterization of ignitable liquids from fire debris. Leak rates were calculated for the three most common types of fire debris evidence containers. The consequences of leaking containers on the recovery and characterization of ignitable liquids were demonstrated. The interactions of hydrocarbons with activated carbon during the extraction of ignitable liquids from the …


Optimization Of Zonal Wavefront Estimation And Curvature Measurements, Weiyao Zou Jan 2007

Optimization Of Zonal Wavefront Estimation And Curvature Measurements, Weiyao Zou

Electronic Theses and Dissertations

Optical testing in adverse environments, ophthalmology and applications where characterization by curvature is leveraged all have a common goal: accurately estimate wavefront shape. This dissertation investigates wavefront sensing techniques as applied to optical testing based on gradient and curvature measurements. Wavefront sensing involves the ability to accurately estimate shape over any aperture geometry, which requires establishing a sampling grid and estimation scheme, quantifying estimation errors caused by measurement noise propagation, and designing an instrument with sufficient accuracy and sensitivity for the application. Starting with gradient-based wavefront sensing, a zonal least-squares wavefront estimation algorithm for any irregular pupil shape and size …


Scanning Fabry-Perot Spectrometer For Terahertz And Gigahertz Spectroscopy Using Dielectric Bragg Mirrors, Justin Cleary Jan 2007

Scanning Fabry-Perot Spectrometer For Terahertz And Gigahertz Spectroscopy Using Dielectric Bragg Mirrors, Justin Cleary

Electronic Theses and Dissertations

A scanning Fabry-Perot transmission filter composed of a pair of dielectric mirrors has been demonstrated at millimeter and sub-millimeter wavelengths. The mirrors are formed by alternating quarter-wave optical thicknesses of silicon and air in the usual Bragg configuration. Detailed theoretical considerations are presented for determining the optimum design including factors that affect achievable finesse. Fundamental loss by lattice and free carrier absorption are considered. High resistivity in the silicon layers was found important for achieving high transmittance and finesse, especially at the longer wavelengths. Also considered are technological factors such as surface roughness, bowing, and misalignment for various proposed manufacturing …


Learning, Detection, Representation, Indexing And Retrieval Of Multi-Agent Events In Videos, Asaad Hakeem Jan 2007

Learning, Detection, Representation, Indexing And Retrieval Of Multi-Agent Events In Videos, Asaad Hakeem

Electronic Theses and Dissertations

The world that we live in is a complex network of agents and their interactions which are termed as events. An instance of an event is composed of directly measurable low-level actions (which I term sub-events) having a temporal order. Also, the agents can act independently (e.g. voting) as well as collectively (e.g. scoring a touch-down in a football game) to perform an event. With the dawn of the new millennium, the low-level vision tasks such as segmentation, object classification, and tracking have become fairly robust. But a representational gap still exists between low-level measurements and high-level understanding of video …


Singlet Oxygen Generation Using New Fluorene-Based Photosensitizers Under One- And Two-Photon Excitation, Stephen James Andrasik Jan 2007

Singlet Oxygen Generation Using New Fluorene-Based Photosensitizers Under One- And Two-Photon Excitation, Stephen James Andrasik

Electronic Theses and Dissertations

Molecular oxygen in its lowest electronically excited state plays an important roll in the field of chemistry. This excited state is often referred to as singlet oxygen and can be generated in a photosensitized process under one- or two-photon excitation of a photosensitizer. It is particularly useful in the field of photodynamic cancer therapy (PDT) where singlet oxygen formation can be used to destroy cancerous tumors. The use of two-photon activated photosensitizers possesses great potential in the field of PDT since near-IR light is used to activate the sensitizer, resulting in deeper penetration of light into biological tissue, less photobleaching …


Analysis Of Mitochondrial Dna Coding Region Snps By Pyrosequencing, Kyle Robert Carl Parker Jan 2007

Analysis Of Mitochondrial Dna Coding Region Snps By Pyrosequencing, Kyle Robert Carl Parker

Electronic Theses and Dissertations

To date, the use of mitochondrial DNA in forensic analysis has relied on the presence of variations in the control region to differentiate between samples. One problem that this analysis has shown is the occurrence of common Haplogroup H haplotypes or identical sequences. Thus, there is a need to enhance the distinguishing power of this type of analysis. One option has been to investigate the mitochondrial coding region for polymorphisms that could differentiate between samples with identical control region haplotypes. The goal of this study has been to identify polymorphic coding region sites for development in a Pyrosequencing assay that …


Discrimination Of Forensic Trace Evidence Using Laser Induced Breakdown Spectroscopy, Candice Bridge Jan 2007

Discrimination Of Forensic Trace Evidence Using Laser Induced Breakdown Spectroscopy, Candice Bridge

Electronic Theses and Dissertations

Elemental analysis in forensic laboratories can be tedious and many trace evidence items are not analyzed to determine their elemental composition. Presently, scanning electron microscopy-energy dispersive x-ray spectroscopy (SEM-EDS) is the primary analytical tool for determining the elemental composition of trace evidence items. However, due to the time it takes to obtain the required vacuum and the limited number of samples that can be analyzed at any one time, SEM-EDS can be impractical for a high volume of evidence items. An alternative instrument that can be used for this type of analysis is laser ablation inductively coupled plasma mass spectrometry …


A Late Holocene Reconstruction Of Ocean Climate Variability In The Gulf Of Maine, Usa, Based On Calibrated Isotope Records And Growth Histories From The Long-Lived Ocean Quahog (Arctica Islandica L.), Alan D. Wanamaker Jan 2007

A Late Holocene Reconstruction Of Ocean Climate Variability In The Gulf Of Maine, Usa, Based On Calibrated Isotope Records And Growth Histories From The Long-Lived Ocean Quahog (Arctica Islandica L.), Alan D. Wanamaker

Electronic Theses and Dissertations

Understanding regional patterns of interannual to decadal-scale climate variability over the past 1000 years is critical for evaluating recently observed trends in atmosphere/ocean conditions, particularly in highly-productive ecosystems such as the Gulf of Maine (GOM) that are sensitive to minor changes in climate and/or changes in slope water input. To develop quantitative relationships between bivalve shell chemistry (d18Oc) and growing conditions, aquaculture-based experiments were developed using Mytilus edulis collected in the GOM and Greenland. These experiments yielded a highly accurate and precise paleothermometer [e.g., T °C = 16.28 (± 0.10) - 4.57 (± 0.15) {d18Oc VPBD – d18Ow VSMOW} + …