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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

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

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

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

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

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 …

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

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 …

Decidability In Algebraic Geometry, John James Iskra

Doctoral Dissertations

The central theme of our investigation is the concept of Decidability in Algebra/Algebraic Geometry. To the best of our knowledge this seems to be novel in the sense that there is no work known to isolate or to focus on the concept of Decidability in the context of Commutative Algebra. Decidability is more restrictive than Grothendieck's concept of formally unramified, but weaker than the concept of étale. In this article we study these relationships by characterizing Decidability for ring-extensions of essentially finite type. In the absence of essential finiteness we can only show, at present, that a separable algebraic …

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 : M → B, 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, …

Alpha And Gamma-Ray Spectroscopic Studies Of Au, Pt, And Ir Nuclei Near The Proton Dripline, Tuck-Meng Goon

Doctoral Dissertations

This dissertation reports the observation of α-decay and in-beam level structures in the neutron-deficient nuclei ^176,174Au, ^173,174Pt, and ¹⁷⁵Ir from an experiment which was performed at Argonne National Laboratory (ANL). A beam of ⁸⁴Sr projectiles was used to bombard ^92,94,96Mo targets. From these reactions, the ^176,178,180Hg compound nuclei were made which eventually decayed into more than 20 product nuclei. The experiment was performed with the Atlas accelerator and utilized the Gammasphere array at the target position in conjunction with the Fragment Mass Analyzer (FMA) for mass identification and a Double-Sided Silicon Strip Detector (DSSD), …

Compatibilizing Polymer Blends Using Reactive Telechelic Oligomers And Copolymers, Charles Paul O'Brien

Doctoral Dissertations

The compatbilization of polymer blends via reactive compatibilization and block copolymers was studied. The result presented in this thesis suggest that the process of reactive compatibiliaztion provides a mechanism by which blocky copolymeric compatibilizers can be formed during processing, as demonstrated by the changes in the mechanical and optical properties of the phase separated polymer blends. The results also show, however, that the presence of unreacted smaller oligomers can act as a plasticizer in the blend and can thus detrimentally affect the mechanical properties of the blend if any remains after processing. Careful control of the mixing conditions or post …

Structural Studies Of Superacidic Systems Using Neutron And High Energy X-Ray Diffraction, Syliva Ellen Mclain

Doctoral Dissertations

The structure of two superacids in the liquid phase, hydrogen fluoride and fluorosulfuric acid, have been determined by neutron and high energy X-ray diffraction in this study. In addition the structure of a molecular Lewis acid, BF₃, has been determined for the liquid state as well as the supercritical state. Experiments were also performed on solutions of the hydronium ion in fluorosulfuric acid by neutron and X-ray diffraction as well as by Raman spectroscopy.

In addition this thesis presents the design and construction of sample cells for neutron and X-ray scattering experiments and the design and construction of …

The Internet Backplane Protocol: Shared Storage For Enhanced Network Infrastructure, Wael Rashad Elwasif

Doctoral Dissertations

Presented here are results pertaining to the utilization of distributed shared storage infrastructure to facilitate application management of remote state. The proposed infrastructure relies on non-privileged storage servers deployed by users at various location in the network. Applications utilize network topology information and storage servers profiles to develop and deploy data access and movement policies that enhance application performance and/or functionality. The combined management of storage and communication resources afforded by the proposed model enable a wide array of new applications that depart from the end-to-end model at the core of the existing Internet. However, this departure is done at …

A Parametric Reactive Distillation Study: Economic Feasibility And Design Heuristics, Craig Alan Hoyme

Doctoral Dissertations

The integration of reaction and distillation into a single column is called reactive distillation or catalytic distillation. Reactive distillation provides many benefits such as reduced capital and operating costs, circumventing non-reactive azeotropes, and overcoming equilibrium limited reactions. Industry has been successful in applying reactive distillation; however the integration of reaction and distillation is not applicable for all reaction/separation systems and it is not always clear when reactive distillation is a feasible design alternative.

Heuristics or rules-of-thumb are an integral part of process systems engineering and are used to provide initial guidance and insight for the analysis of process feasibility and …

Development Of Novel Substrates And Sampling Techniques For The Analysis Of Drugs And Model Environmental Pollutants Via Surface Enhanced Raman Spectroscopy (Sers), Marco Antonio De Jesús

Doctoral Dissertations

Surface Enhanced Raman Spectroscopy (SERS) has shown promise for the analysis of environmental and pharmaceutically relevant compounds due to its tremendous enhancement of Raman signals and the large amount of structural information provided by the technique. Despite these advantages, SERS has not been established as a routine analytical tool due to limitations in the analytical figures of merit such as reproducibility and linear dynamic range. This is due in part to the fact that the continuous irradiation of the laser beam over the SERS substrate can promote the rapid decomposition of sample analytes which significantly broaden and diminish the intensities …