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Full-Text Articles in Physical Sciences and Mathematics

Single Muon Production And Implications For Charm In √Sn N = 200 Gev Au+Au Collisions, Andrew Miles Glenn Dec 2004

Single Muon Production And Implications For Charm In √Sn N = 200 Gev Au+Au Collisions, Andrew Miles Glenn

Doctoral Dissertations

The PHENIX experiment, located at the Brookhaven National Laboratory’s Rela- tivistic Heavy Ion Collider, is designed to study high energy proton+proton and nu- cleus+nucleus collisions in order to characterize hot and dense nuclear matter. This dissertation presents the first analysis of single muon production in √sN N = 200 GeV Au+Au reactions. Implications of the forward rapidity measurements for charm pro- duction are discussed. Motivation for charm production measurements and the role of open charm in characterizing the medium created in relativistic heavy ion collisions are presented, and the importance of measurements at forward rapidity is established. The results of …


The Function Of The Stress Hormone Cortisol In Disease Susceptibility Of Channel Catfish, Ictalurus Punctatus, Todd David Sink Dec 2004

The Function Of The Stress Hormone Cortisol In Disease Susceptibility Of Channel Catfish, Ictalurus Punctatus, Todd David Sink

Doctoral Dissertations

The purpose of these studies was to examine the roles that the stress hormone cortisol plays in disease susceptibility of channel catfish, Ictalurus punctatus, to enteric septicemia of catfish (ESC). ESC is a serious disease of the channel catfish industry with annual losses in the millions. Few treatment options such as antibiotics and vaccines are available, but efficacy of treatments has proven to be limited. Deeper investigations into the physiological causes of disease in fish that accompany commercial production are needed to promote understanding of disease treatment and prevention.

Disease challenges using Edwardsiella ictaluri, the pathogenic bacterium that …


Metallic Ferroelectricity And Superconductivity In The Transition Metal Oxide Pyrochlore Cd2Re2O7, Jian He Dec 2004

Metallic Ferroelectricity And Superconductivity In The Transition Metal Oxide Pyrochlore Cd2Re2O7, Jian He

Doctoral Dissertations

Single crystalline samples of transition metal oxide Cd2Re2O7, the first superconductor among pyrochlore oxides with general formula A2B2O7 and the first example of “ferroelectric metal” theoretically proposed by P.W. Anderson and E.I. Blount back in 1960s, have been grown using vapor transport and carefully characterized, regarding its chemical stoichiometry and structure. In addition to the superconductivity transition, two normal state phase transitions and the anomalous high temperature phase have been comprehensively investigated, by means of transport, thermodynamic and spectroscopy techniques. The system undergoes a subtle continuous cubic-to-tetragonal phase transition …


Electrochemical Investigation Of Anthraquinone Tagged Oligonucleotides And Electrodes, Adam N. Mullenix Dec 2004

Electrochemical Investigation Of Anthraquinone Tagged Oligonucleotides And Electrodes, Adam N. Mullenix

Doctoral Dissertations

The DNA double helix is one of the most studied structures in modern science. These molecules provide the basic blueprint for all life as it is presently known to exist. Continuing studies of this structure, and the implications that come with them, currently yield a constantly growing base of knowledge for the study of drug interactions, specifics in the role of the sequence of bases in the DNA chain, and an understanding of the small structural abnormalities and the resulting benefits and problems in the human genome. The research presented herein attempts to examine such interactions using anthraquinone-based modifications for …


Fundamental Investigations And Analysis Of Chiral Matter Using Simple Spectroscopic Techniques, Rodney Jamel Sullivan Dec 2004

Fundamental Investigations And Analysis Of Chiral Matter Using Simple Spectroscopic Techniques, Rodney Jamel Sullivan

Doctoral Dissertations

Fundamental investigations of circular dichroism were performed on (R)-(+)-3- methylcyclopentanone, (R)-(-)-2-butylamine, and (S)-(+)-2-butylamine in the liquid and vapor phase to show that solvents often have a structure-masking effect on the circular dichroism for a given molecule. Also, the solid state circular dichroism of cubic sodium chlorate crystals was successfully measured in the midst of adverse experimental circumstances. With these single photon circular dichroism studies at hand, a new technique for measuring circular dichroism was introduced for an advanced investigation of (R)-(+)-3-methylcyclopentanone. The resonance enhanced multiphoton ionization of (R)-(+)-3-methylcyclopentanone was performed …


Com- Putational Subset Model Selection Algorithms And Applications, Xinli Bao Dec 2004

Com- Putational Subset Model Selection Algorithms And Applications, Xinli Bao

Doctoral Dissertations

This dissertation develops new computationally e±cient algorithms for identifying the subset of variables that minimizes any desired information criteria in model selection.

In recent years, the statistical literature has placed more and more empha- sis on information theoretic model selection criteria. A model selection crite- rion chooses model that \closely" approximates the true underlying model. Recent years have also seen many exciting developments in the model se- lection techniques. As demand increases for data mining of massive data sets with many variables, the demand for model selection techniques are be- coming much stronger and needed. To this end, we introduce …


Crown Reductions And Decompositions: Theoretical Results And Practical Methods, William Henry Suters, Iii Dec 2004

Crown Reductions And Decompositions: Theoretical Results And Practical Methods, William Henry Suters, Iii

Masters Theses

Two kernelization schemes for the vertex cover problem, an NP-hard problem in graph theory, are compared. The first, crown reduction, is based on the identification of a graph structure called a crown and is relatively new while the second, LP-kernelization has been used for some time. A proof of the crown reduction algorithm is presented, the algorithm is implemented and theorems are proven concerning its performance. Experiments are conducted comparing the performance of crown reduction and LP- kernelization on real world biological graphs. Next, theorems are presented that provide a logical connection between the crown structure and LP-kernelization. Finally, an …


Maximal Clique Enumeration And Related Tools For Microarray Data Analysis, Nicole E. Baldwin Dec 2004

Maximal Clique Enumeration And Related Tools For Microarray Data Analysis, Nicole E. Baldwin

Masters Theses

The purpose of this study was to investigate the utility of exact maximal clique enumeration in DNA microarray analysis, to analyze and improve upon existing exact maximal clique enumeration algorithms, and to develop new clique-based algorithms to assist in the analysis as indicated during the course of the study. As a first test, microarray data sets comprised of pre-classified human lung tissue samples were obtained through the Critical Assessment of Microarray Data Analysis (CAMDA) conference. A combination of exact maximal clique enumeration and approximate dominating set was used to attempt to classify the samples.

In another test, maximal clique enumeration …


Joint Size Estimation Using Joint Traces On Borehole Walls, Christopher James Heiny Dec 2004

Joint Size Estimation Using Joint Traces On Borehole Walls, Christopher James Heiny

Masters Theses

One approach to characterizing subsurface joint populations is to assume
surface joint patterns are representative of joints at depth. Yet, many times, either the analogous surface joints are unexposed, or absent because surface rocks did not experience the same deformation history. The alternative of direct subsurface characterization has been limited by joints not being resolvable in seismic data and borehole data not yielding fracture size. The present approach uses the subsurface geometry of joint/borehole intersections to estimate mean joint size (mean joint length and width) and aspect ratio (joint length to width ratio), and presents a new method for determining …


Low Energy Excitations In Spin Clusters And Molecular Solids, Jason Thomas Haraldsen Dec 2004

Low Energy Excitations In Spin Clusters And Molecular Solids, Jason Thomas Haraldsen

Masters Theses

This thesis investigates low energy magnetic and vibrational excitations in molecular solids. Analytical and numerical studies of these two types of excitations, both in idealized systems and in more complicated models that are thought to capture the relevant physics of several materials. The materials considered include molecular magnets and layered organic superconductors and semiconductors. Our results include exact expressions for certain magnetic observables, neutron scattering structure factors for small spin 1/2 clusters, studies of the molecular dynamics of Fe8Br8 molecular magnet, the e®ects of symmetry breaking in (DT-TTF)2Au(mnt)2 spin ladder candidate, and the importance …


Understanding The Dynamics Of Molecular Solids, Roman Wesolowski Dec 2004

Understanding The Dynamics Of Molecular Solids, Roman Wesolowski

Masters Theses

Superconductors, single-molecule magnets, and spin-ladders materials are at the center of interest in condensed matter science. All of these materials have incredibly important potential applications and their exploration is the key to the future technologies. We carried out various measurements on representative compounds of each group of interest. The main tool for all these projects was optical spectroscopy, varied in each case to apply magnetic field or change temperature. In our magneto-optical measurements of κ-(ET)2Cu[N(CN)2]Br and κ-(ET)2Cu[N(CN)2]Cl, we sought to understand correlations between intramolecular vibrations and superconductivity. We found several …


Probabilistic Suffix Models For Windows Application Behavior Profiling: Framework And Initial Results, Geoffrey Alan Mazeroff Dec 2004

Probabilistic Suffix Models For Windows Application Behavior Profiling: Framework And Initial Results, Geoffrey Alan Mazeroff

Masters Theses

Developing statistical/structural models of code execution behavior is of considerable practical importance. This thesis describes a framework for employing probabilistic suffix models as a means of constructing behavior profiles from code-traces of Windows XP applications. Emphasis is placed on the inference and use of probabilistic suffix trees and automata with new contributions in the area of auxiliary symbol distributions. An initial real-time classification system is discussed and preliminary results of detecting known benign and viral applications are presented.


Analysis Of Reflected Spectral Signatures And Detection Of Geophysical Disturbance Using Hyperspectral Imagery, Forrest Mccoy Hoffman Dec 2004

Analysis Of Reflected Spectral Signatures And Detection Of Geophysical Disturbance Using Hyperspectral Imagery, Forrest Mccoy Hoffman

Masters Theses

Geophysical disturbances resulting from human activities often have significant
consequences for plants and animals, and even for entire ecosystems.Disturbances resulting from petroleum exploration and production activities can have long term impacts on soils, watersheds, rivers and lakes, vegetation, wildlife, and humans. These anthropogenic disturbances are frequently the result of hydrocarbon (oil) or produced water (brine) spills. Brine is usually produced simultaneously with oil or gas. The ability to detect brine spills with remote sensing techniques would be valuable to petroleum companies and industry regulators. The objectives of this research were to 1) determine if brine spills could be detected spectroscopically, …


A Multiple Linear Regression Analysis On Mathematics Placement At The University Of Tennessee, Knoxville, Steven K. Moore Dec 2004

A Multiple Linear Regression Analysis On Mathematics Placement At The University Of Tennessee, Knoxville, Steven K. Moore

Masters Theses

This paper looks at solving the least squares problem and then using that theory to solve a simple multiple regression analysis for placing students into mathematics courses at the University of Tennessee, Knoxville.

The first chapter is an introduction and a basic outline of the problem. Chapter 2 outlines the theory behind solving an actual least squares problem for both the general case and for the particular case of nonsingular matrices. Chapter 3 discusses assumptions that must be made when running the analysis.

In chapters 4 and 5 computers are discussed and software output is explained. Finally, Chapter 6 gives …


Ellipsometric Measurement Of Swelling Properties Associated With Ph Responsive Hydrogels In Solution, James F. Patton Dec 2004

Ellipsometric Measurement Of Swelling Properties Associated With Ph Responsive Hydrogels In Solution, James F. Patton

Masters Theses

Previous investigations have demonstrated that aqueous solutions containing hydrogels using 2-hydroxyethyl methacrylate (2-HEMA) as one of the monomer components swell reversibly under variable conditions of pH, temperature, and ionic strength, based upon weight gain ratios. A more unique approach will be employed to measure swelling properties associated with pH responsive hydrogels in buffered solutions, namely ellipsometry. Traditionally ellipsometry has been used to measure thickness of materials on a nanoscale dimension under ambient conditions. Finally, more novel approaches of employing hydrogel swelling response properties will be investigated; including response to glucose and enzyme loading schemes. The goal of our project will …


A Framework For Downloading Wide-Area Files, Rebecca Lynn Collins Dec 2004

A Framework For Downloading Wide-Area Files, Rebecca Lynn Collins

Masters Theses

The challenge of efficiently retrieving files that are broken into segments and replicated across the widearea is of prime importance to wide-area, peer-to-peer, and Grid file systems. Two different algorithms addressing this challenge have been proposed and evaluated. While both have been successful in different performance scenarios, there has been no unifying work that can view both algorithms under a single framework. In this thesis, we define such a framework, where download algorithms are defined in terms of the four dimensions that the client always controls: the number of simultaneous downloads, the degree of work replication, the failover strategy, and …


Cross Sections Fall 2004, Department Of Physics And Astronomy Oct 2004

Cross Sections Fall 2004, Department Of Physics And Astronomy

Cross Sections

No abstract provided.


Inter- And Intra-Species Variation In Three Crown Condition Indicators For Seven Tree Species In The Southeastern United States, Kadonna Cheryl Randolph Aug 2004

Inter- And Intra-Species Variation In Three Crown Condition Indicators For Seven Tree Species In The Southeastern United States, Kadonna Cheryl Randolph

Doctoral Dissertations

The USDA Forest Service utilizes assessments of tree crowns, specifically crown density, crown dieback, and foliage transparency, to accomplish in part its mission of reporting the long-term status, changes, and trends in forest ecosystem health in the United States. To aid interpretation and provide general guidelines of health across all species the crown condition assessments are classed into categories ranging from “good” to “poor.” The purpose of this research was to evaluate and describe the variation in crown density, crown dieback, and foliage transparency between and within species, and to critique the appropriateness of the current threshold levels. In addition, …


Effect Of Nanoscale Confinement On The Structure And Properties Of Single Conjugated Polymer Molecules, Pradeep K. Koyadankizhakkedath Aug 2004

Effect Of Nanoscale Confinement On The Structure And Properties Of Single Conjugated Polymer Molecules, Pradeep K. Koyadankizhakkedath

Doctoral Dissertations

The research presented in this thesis was motivated by questions on the effect of nanoscale confinement on molecular conformation and related photophysical properties of conjugated polymers. Using microdroplet techniques as a method of isolating single molecules of various poly[phenylene vinylenes] we discovered that poly[2-methoxy-5- (2’-ethyl-hexyloxy)-1,4-phenylene vinylene] (MEH-PPV) and poly[2-Methoxy-5-(2'- ethylhexyloxy)-1,4-(cyanovinylene)phenylene] (CN-PPV) can be deposited on precleaned glass substrates with unique transition moment orientation. Structural investigation using a combination of fluorescence emission pattern imaging, atomic force microscopy and polarization anisotropy measurements revealed that individual polymer nanostructures had a high degree of intra-molecular with the long axis of the conjugated segment oriented …


Finding Functional Gene Relationships Using The Semantic Gene Organizer (Sgo), Kevin Erich Heinrich Aug 2004

Finding Functional Gene Relationships Using The Semantic Gene Organizer (Sgo), Kevin Erich Heinrich

Masters Theses

Understanding functional gene relationships is a major challenge in bioninformatics and computational biology. Currently, many approaches extract gene relationships via term co-occurrence models from the biomedical literature. Unfortunately, however, many genes that are experimentally identified to be related have not been previously studied together. As a result, many automated models fail to help researchers understand the nature of the relationships. In this work, the particular schema used tomine genomic data is called Latent
Semantic Indexing (LSI). LSI performs a singular-value decomposition (SVD) to produce a low-rank approximation of the data set. Effectively, it allows queries to be interpreted in a …


Spectroscopy Using Short-Path Surface Plasmon Dispersion, Philip Ryan Boudreaux Aug 2004

Spectroscopy Using Short-Path Surface Plasmon Dispersion, Philip Ryan Boudreaux

Masters Theses

A miniature surface-plasmon based spectrometer is presented for both the near zone and the far zone. In the near zone four different experiments have been completed with this system. It will be shown that with 632, 614, 543, and 440 nm incident lasers upon the system there is good agreement between experimental and theoretical transmission spectra. This system is shown to provide transmission spectra of different broad band-pass, glass filters across the visible wavelength range with high stray-light rejection at low resolution. These spectra are compared to those taken with a commercial spectrophotometer. Spectra of solutions of the laser dye …


Modeling The Cascade Of Reactions In Visual Transduction, Philip Torry Patton Aug 2004

Modeling The Cascade Of Reactions In Visual Transduction, Philip Torry Patton

Masters Theses

Phototransduction in the process by which light energy is transferred to an electrical potential by photoreceptors in the eye. Recently, Hamer et al proposed a mechanism for the cascade of reactions that occurs when a rhodopsin molecule on the surface of a disc in the rod photoreceptor becomes activated. From these reactions, one can derive a system of ordinary differential equations to simulate phototransduction.

These ODEs are solved numerically using forward Euler’s method. The products of this cascade are then used to predict the drop in photocurrent that occurs. A kinetic Monte Carlo simulation with the Gillespie algorithm is implemented …


Mathematical Representations Of The Architecture Of Graphical User Interfaces, Eric Freeman Mann Aug 2004

Mathematical Representations Of The Architecture Of Graphical User Interfaces, Eric Freeman Mann

Masters Theses

This text is an introduction to mathematical representations of graphical user interfaces, GUIs. Vectors are employed as a means to represent the state of a GUI and the user interaction with a GUI. These representations form a model of the behavior of a GUI over time. The usefulness of the model in testing and developing well-behaved GUIs is discussed and demonstrated by example.


A Clustering Method Based On Nonnegative Matrix Factorization For Text Mining, Farial Shahnaz Aug 2004

A Clustering Method Based On Nonnegative Matrix Factorization For Text Mining, Farial Shahnaz

Masters Theses

This study presents a methodology for automatically identifying and clustering semantic features or topics in a heterogeneous text collection. The methodology involves encoding the text data using a low rank nonnegative matrix factorization algorithm to retain natural data nonnegativity, thereby eliminating the need to use subtractive basis vector and encoding calculations present in other techniques such as principal component analysis for semantic feature abstraction. Existing techniques for nonnegative matrix factorization are reviewed and a new hybrid technique for nonnegative matrix factorization is proposed. Performance evaluations of the proposed method is conducted on a few benchmark text collections used in standard …


A Whole Genome Phylogeny Using Truncated Pivoted Qr Decomposition, Shakhina Abdimajidovna Pulatova Aug 2004

A Whole Genome Phylogeny Using Truncated Pivoted Qr Decomposition, Shakhina Abdimajidovna Pulatova

Masters Theses

The increasing availability of whole genome sequences in public databases has stimulated the development of new methods to automatically compare and categorize genes and species. Recently developed methods based on the singular value decomposition (SVD) allow for the simultaneous identification and definition of well concerved motifs and gene families using very large whole genome datasets. In contrast, this work discusses the use of a truncated pivoted QR factorization as a scalable alternative to the SVD for comparing whole genomes in a phylogenetic context. This algorithm computes the R factor of the decomposition without forming the Q factor or altering the …


A Study Of Hidden Markov Model, Yang Liu Aug 2004

A Study Of Hidden Markov Model, Yang Liu

Masters Theses

The purpose of this thesis is fourfold: Introduce the definition of Hidden Markov Model. Present three problems about HMM that must be solved for the model to be useful in real-world application. Cover the solution of the three basic problems; explain some algorithms in detail as well as the mathematical proof. And finally, give some examples to show how these algorithms work.


The Effect Of A 6-Week Strength And Balance Training Program On Navicular Drop And Proprioception In Excessive Pronated Foot, Ryoko Suzuki Aug 2004

The Effect Of A 6-Week Strength And Balance Training Program On Navicular Drop And Proprioception In Excessive Pronated Foot, Ryoko Suzuki

Masters Theses

The purpose of this study was to determine the effect of a 6-week strength and balance training program on navicular drop and proprioception in subjects with excessive pronated feet. Eleven subjects who exhibited excessive pronated feet from student population participated in this study. Navicular drop test was used to assess the subtalar joint motion. The Biodex Stability System was used to determine balance using three indices; (1) overall stability index (OSI), (2) the anterior-posterior stability index (APSI), and (3) the medial-lateral stability index (MLSI). In a randomized order, the subjects were tested balancing on each foot at the two different …


Productivity Analysis And Use Of Sequence-Based Specification In A Web-Development Environment, Carla Renee Sparks Aug 2004

Productivity Analysis And Use Of Sequence-Based Specification In A Web-Development Environment, Carla Renee Sparks

Masters Theses

This study evaluates the productivity of a software team in a web-development company and assesses the effects of the sequence-based specifications process on productivity and software accuracy in this environment. This study compares two software projects completed at GoTrain Corporation in 2001 and 2002. GoTrain is an application service provider and delivers environmental, safety and health (ES&H) training courses to a variety of clients through an Internet-based learning management system (LMS), called the Academy.

GoTrain was established in 1999 through the merger of two small companies – a training services organization and a web design group. Because neither of the …


Fractured Branched Circle Packings On The Plane, James Russell Ashe Aug 2004

Fractured Branched Circle Packings On The Plane, James Russell Ashe

Masters Theses

William Thurston first proposed that real circles could be used to approximate the underlying infinitesimal circles of conformal maps in 1985. Inspired pioneers developed Circle Packing into a very rich and deep field that can be used as a method for constructing discrete conformal maps of surfaces on different types of geometries. Offering the advantages of a computational method that lends itself to experimentation and the easy creation of visual models, Circle Packing has proven itself as valuable new tool in approaching both old and new problems.

In particular, Circle Packing has been used to make discrete analogues of continuous …


Fibrator Properties Of Pl Manifolds, Violeta Vasilevska Aug 2004

Fibrator Properties Of Pl Manifolds, Violeta Vasilevska

Doctoral Dissertations

In the early 90s, R.Daverman defined the concept of the PL fibrator ([12]). PL fibrators, by definition, provide detection of PL approximate fibrations. Daver- man defines a closed, connected, orientable PL n-manifold to be a codimension-k PL orientable fibrator if for all closed, connected, orientable PL (n + k)-manifolds M and PL maps p : MB, where B is a polyhedron, such that each fiber collapses to an n-complex homotopy equivalent to Nn, p is always an approximate fibration.

If N is a codimension-k PL orientable fibrator for all k > 0, …