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2007

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Articles 5641 - 5670 of 5716

Full-Text Articles in Physical Sciences and Mathematics

A Taxonomic Survey Of Lamp Flora (Algae And Cyanobacteria) In Electrically Lit Passages Within Mammoth Cave National Park, Kentucky, Thomas Smith, Rick Olson Jan 2007

A Taxonomic Survey Of Lamp Flora (Algae And Cyanobacteria) In Electrically Lit Passages Within Mammoth Cave National Park, Kentucky, Thomas Smith, Rick Olson

International Journal of Speleology

A taxonomic survey of the lamp flora from electrically lit passages in Mammoth Cave, Mammoth Cave National Park, identified 28 species. Overall, cyanobacteria were dominant represented by 14 species (50% of the total), green algae had eight species (29%), and six diatoms species (21%) were present. There was not a correlation between species diversity and temperature, but there is a general trend of increasing diversity with warmer temperatures. There were two algal or cyanobacterial species identified in this study that overlapped with previous studies. There is a lack of continuity between previous studies only having one species identified in more …

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Clustering Blog Information, Mayank Prakash Jaiswal Jan 2007

Clustering Blog Information, Mayank Prakash Jaiswal

Master's Projects

Blogs form an important source of information in today’s internet world. There are blogs on different topics such as technical, health, electronic gadgets, shopping, etc. However, most of the blog websites have the blogs arranged in chronological order rather than its contents. Such arrangement of blogs makes it difficult for the user searching information about a particular topic from the blog. To resolve this problem, we propose an approach to cluster the blogs based on its content. We studied several clustering algorithms available. The objective of this report is to understand various steps involved in clustering blog information and working …

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Concept Analysis In Web Documents, Rajesh Singh Jan 2007

Concept Analysis In Web Documents, Rajesh Singh

Master's Projects

A Keyword within a text/web document represents some human thought. The interaction of keywords leads to narrowing of scope of human thought by forming a more precise semantic entity called concepts. Analyzing a set of document not only requires analysis of the keywords within those documents but also their interactions within a document. In this new approach a set of documents can be analyzed where by the interactions of its keywords is also considered in finding the important concepts. These concepts can be used to cluster them into smaller subsets such that documents in each cluster will be semantically similar.

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Emotional And Domain Concept Enhancements To Alicebot, Alvin Cho Jan 2007

Emotional And Domain Concept Enhancements To Alicebot, Alvin Cho

Master's Projects

Extensive research and development have been done in the area of human simulation and artificial intelligence and their related fields, such as common sense knowledge bases, chatterbots, natural language parsing, semantic analysis, synthetic actors, and cognitive sciences. This paper takes part in that extensive research by focusing on the improvement of human simulation in chatterbots, specifically in Alicebot, a prominent non-emotional pattern-matching chatbot. An emotion and personality model is added to Alicebot so that it can make decisions based on its emotions and personality. Alicebot is also augmented with the ability to determine what it likes or does not like …

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Validation And Verification Of Aircraft Control Software For Control Improvement, Thien-Anh Pham Jan 2007

Validation And Verification Of Aircraft Control Software For Control Improvement, Thien-Anh Pham

Master's Projects

Validation and Verification are important processes used to ensure software safety and reliability. The Cooper-Harper Aircraft Handling Qualities Rating is one of the techniques developed and used by NASA researchers to verify and validate control systems for aircrafts. Using the Validation and Verification result of controller software to improve controller's performance will be one of the main objectives of this process. Real user feedback will be used to tune PI controller in order for it to perform better. The Cooper-Harper Aircraft Handling Qualities Rating can be used to justify the performance of the improved system.

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Preservice Teachers’ Mapping Structures Acting On Representational Quantities, Gunhan Caglayan Jan 2007

Preservice Teachers’ Mapping Structures Acting On Representational Quantities, Gunhan Caglayan

Proceedings of the Annual Meeting of the Georgia Association of Mathematics Teacher Educators

In this article, I write about my research on five preservice secondary teachers’ (PST) understanding and sense making of representational quantities associated with magnetic color cubes and tiles. Data came from individual interviews during which I asked PST problems guided by five main tasks: prime and composite numbers, summation of counting numbers, odd numbers, even numbers, and polynomial expressions in x and y. My work drew upon an analysis framework (Behr et. al, 1994) supported by a unit coordination construct (Steffe, 1988) associated with linear and areal quantities inherent in the nature of figures produced by these PST. Linear quantities …

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The Mathematical Preparation Of Secondary School Teachers, Kelly W. Edenfield Jan 2007

The Mathematical Preparation Of Secondary School Teachers, Kelly W. Edenfield

Proceedings of the Annual Meeting of the Georgia Association of Mathematics Teacher Educators

In the summer of 2007, a group of doctoral students at the University of Georgia gathered to discuss the mathematical preparation of secondary teachers. The group used Mathematics for High School Teachers: An Advanced Perspective by Usiskin, Peressini, Marchisotto, and Stanley (2003) as the catalyst for the discussion. Participants agreed that future teachers need opportunities to examine high school and college mathematics differently from the way they had as students, with specific emphasis on connections, representations, and history. Features of this text that were highlighted in the discussions were the attention topics with commonly held misconceptions, the historical rationales and …

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The Kennesaw State University Mathematics Methods Model, Angela L. Teachey Jan 2007

The Kennesaw State University Mathematics Methods Model, Angela L. Teachey

Proceedings of the Annual Meeting of the Georgia Association of Mathematics Teacher Educators

Kennesaw State University’s comprehensive, nine-credit-hour, methods course integrates general and mathematics-specific pedagogical training with a structured four-week field experience prior to student teaching. This course blends essential units on conceptual understanding of mathematics, lesson planning, assessment, classroom management, and diversity with mathematics-specific methods. All topics are aligned with National Council of Teachers of Mathematics standards and Georgia Performance Standards. Throughout the course, students complete a variety of assignments that require them to practice the skills highlighted in class readings and discussions, and they adapt and generalize those skills during their field experiences. Students have numerous opportunities in class and in …

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The Application Of Controlled Radical Polymerization Processes On The Graft Copolymerization Of Hydrophobic Substituents Onto Guar Gum And Guar Gum Derivatives, Veronica Holmes Jan 2007

The Application Of Controlled Radical Polymerization Processes On The Graft Copolymerization Of Hydrophobic Substituents Onto Guar Gum And Guar Gum Derivatives, Veronica Holmes

LSU Doctoral Dissertations

Guar gum is a naturally occurring polysaccharide; guar gum and its derivatives, such as carboxymethyl guar gum (CMG) are widely used in the oil and gas industry. A hydraulic fracturing fluid for rock formations to enhance oil recovery (EOR) is comprised of viscosifier, gelled CMG, and sand particles (proppants). The gel is mixed with proppant (sand) and pumped at high rate and high pressure into an oil/gas well to the hydrocarbon-producing zone. The applied pressure will force the rock formation to fracture allowing entry of the guar gel/sand mixture. The mixture then fills the resultant fracture. The viscosity of the …

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Incipient Continental Rifting: Insights From The Okavango Rift Zone, Northwestern Botswana, Baraka D. Kinabo Jan 2007

Incipient Continental Rifting: Insights From The Okavango Rift Zone, Northwestern Botswana, Baraka D. Kinabo

Doctoral Dissertations

"In this dissertation aeromagnetic, gravity, and Shuttle Radar Topography Mission Digital Elevation Model (SRTM DEM) data from the Okavango Rift Zone in northwest Botswana are used to map the distribution of rift and basement structures. The distribution of these structures provide useful insights into the early stages of continental rifting. The objectives of this study are (1) assessing the role of pre-existing structures on rift basin development, (2) characterizing the geometry of the nascent rift basins, (3) documenting fault growth and propagation patterns, and (4) investigating the border fault development"--Abstract, page iv.

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Synthetic Methods For Biologically Relevant Organofluorine Compounds, Meher Perambuduru Jan 2007

Synthetic Methods For Biologically Relevant Organofluorine Compounds, Meher Perambuduru

Doctoral Dissertations

"This thesis describes novel synthetic methodologies for the synthesis of biologically relevant organofluorine compounds"--Abstract, page iii.

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The Application Of Electrospray Ionization Coupled To Ultrahigh Resolution Mass Spectrometry For The Molecular Characterization Of Natural Organic Matter, Rachel L. Sleighter, Patrick G. Hatcher Jan 2007

The Application Of Electrospray Ionization Coupled To Ultrahigh Resolution Mass Spectrometry For The Molecular Characterization Of Natural Organic Matter, Rachel L. Sleighter, Patrick G. Hatcher

Chemistry & Biochemistry Faculty Publications

Mass spectrometry has recently played a key role in the understanding of natural organic matter (NOM) by providing molecular-level details about its composition. NOM, a complex assemblage of organic molecules present in natural waters and soils/sediments, has the ability to bind and transport anthropogenic materials. An improved understanding of its composition is crucial in order to understand how pollutants interact with NOM and how NOM cycles through global carbon cycles. In the past, low-resolution (> 3000) mass analyzers have offered some insights into the structure of NOM, but emerging ultrahigh resolution (> 200000) techniques such as electrospray ionization (ESI) coupled …

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Quark Contribution To The Small-𝔁 Evolution Of Color Dipole, Ian Balitsky Jan 2007

Quark Contribution To The Small-𝔁 Evolution Of Color Dipole, Ian Balitsky

Physics Faculty Publications

The small-𝔁 deep inelastic scattering in the saturation region is governed by the nonlinear evolution of Wilson-lines operators. In the leading logarithmic approximation it is given by the Balitsky-Kovchegov (BK) equation for the evolution of color dipoles. In the next-to-leading order (NLO) the nonlinear equation gets contributions from quark and gluon loops. In this paper I calculate the quark-loop contribution to small-𝔁 evolution of Wilson lines in the NLO. It turns out that there are no new operators at the one-loop level—just as at the tree level, the high-energy scattering can be described in terms of Wilson lines. In addition, …

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Low And Medium Β Superconducting Cavities And Accelerators, Jean R. Delayen Jan 2007

Low And Medium Β Superconducting Cavities And Accelerators, Jean R. Delayen

Physics Faculty Publications

No abstract provided.

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A General Model Of Resistive Wall Instability In Linear Accelerators, Jean R. Delayen Jan 2007

A General Model Of Resistive Wall Instability In Linear Accelerators, Jean R. Delayen

Physics Faculty Publications

A general model for wakefield-generated instabilities in linear accelerators, originally developed for cumulative beam breakup [1], is applied to the resistive wall instability. The general solution for various bunch charge distributions and application to various accelerator configurations are presented.

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An Evaluation Of Supercritical Drying And Peg/Freeze Drying Of Waterlogged Archaeological Wood, Eric Schindelholz, Robert Blanchette, Desmond C. Cook, Michael Drews, Steve Hand, Benjamin Held, Joel Jurgens, Betty Seifert Jan 2007

An Evaluation Of Supercritical Drying And Peg/Freeze Drying Of Waterlogged Archaeological Wood, Eric Schindelholz, Robert Blanchette, Desmond C. Cook, Michael Drews, Steve Hand, Benjamin Held, Joel Jurgens, Betty Seifert

Physics Faculty Publications

This study was undertaken to evaluate the physical effects of drying waterlogged archaeological wood using supercritical carbon dioxide as compared to air drying and the popular polyethylene glycol (PEG)/freeze drying method. Previous studies have shown supercritical drying to be a potentially advantageous alternative to current methods of drying waterlogged wood through reduced processing time, minimal shrinkage, and increased success for reversibility. Samples in the form of blocks and planks of a few centimeters in size were prepared from two archaeological waterlogged wood sources and grouped into three treatment sets: one for air drying, one for PEG/freeze drying, and the other …

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Quark-Hadron Duality In Spin Structure Functions G(1)(P) And G(1)(D), P. E. Bosted, K. V. Dharmawardane, G. E. Dodge, T. A. Forest, S. E. Kuhn, Y. Prok, G. Adams, M. Amarian, P. Ambrozewicz, M. Anghinolfi, H. Bagdasaryan, M. Bektasoglu, S. Bültmann, S. L. Careccia, G. Gavalian, N. Guler, C. E. Hyde-Wright, H. G. Juengst, A. Klein, J. Lachniet, R. A. Niyazov, L. M. Qin, F. Sabatié, S. Tkachenko, L. B. Weinstein, J. Yun, J. Zhang Jan 2007

Quark-Hadron Duality In Spin Structure Functions G(1)(P) And G(1)(D), P. E. Bosted, K. V. Dharmawardane, G. E. Dodge, T. A. Forest, S. E. Kuhn, Y. Prok, G. Adams, M. Amarian, P. Ambrozewicz, M. Anghinolfi, H. Bagdasaryan, M. Bektasoglu, S. Bültmann, S. L. Careccia, G. Gavalian, N. Guler, C. E. Hyde-Wright, H. G. Juengst, A. Klein, J. Lachniet, R. A. Niyazov, L. M. Qin, F. Sabatié, S. Tkachenko, L. B. Weinstein, J. Yun, J. Zhang

Physics Faculty Publications

New measurements of the spin structure functions of the proton and deuteron g(1)(p)(x,Q2) and g(1)(d)(x,Q2) in the nucleon resonance region are compared with extrapolations of target-mass-corrected next-to-leading-order (NLO) QCD fits to higher energy data. Averaged over the entire resonance region (W <2 >GeV), the data and QCD fits are in good agreement in both magnitude and Q2 dependence for Q2 >1.7 GeV2/c2. This "global" duality appears to result from cancellations among the prominent "local" resonance regions: in particular strong σ …

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Erratum: Cross Sections For The 𝛾p -> K*⁰ Σ⁺ Reaction At E𝛾 = 1.7-3.0 Gev (Physical Review C. 75, 042201), M. Amarian, H. Bagdasaryan, S. Bültmann, G. E. Dodge, G. Gavalian, C. E. Hyde-Wright, A. Klein, S. E. Kuhn, F. Sabatié, L. B. Weinstein, Et. Al., The Clas Collaboration Jan 2007

Erratum: Cross Sections For The 𝛾p -> K*⁰ Σ⁺ Reaction At E𝛾 = 1.7-3.0 Gev (Physical Review C. 75, 042201), M. Amarian, H. Bagdasaryan, S. Bültmann, G. E. Dodge, G. Gavalian, C. E. Hyde-Wright, A. Klein, S. E. Kuhn, F. Sabatié, L. B. Weinstein, Et. Al., The Clas Collaboration

Physics Faculty Publications

No abstract provided.

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First Measurement Of Beam-Recoil Observables CX And CZ In Hyperon Photoproduction, M. J. Amaryan, H. Bagdasaryan, H. Bektasoglu, S. Bültmann, S. L. Careccia, K. V. Dharmawardane, G. E. Dodge, T. A. Forest, N. Guler, C. E. Hyde-Wright, N. Kalantarians, A. Klein, S. E. Kuhn, J. Lachniet, M. R. Niroula, R. A. Niyazov, L. M. Qin, F. Sabatié, S. Tkachenko, L. B. Weinstein, J. Yun, Et Al., Clas Collaboration Jan 2007

First Measurement Of Beam-Recoil Observables CX And CZ In Hyperon Photoproduction, M. J. Amaryan, H. Bagdasaryan, H. Bektasoglu, S. Bültmann, S. L. Careccia, K. V. Dharmawardane, G. E. Dodge, T. A. Forest, N. Guler, C. E. Hyde-Wright, N. Kalantarians, A. Klein, S. E. Kuhn, J. Lachniet, M. R. Niroula, R. A. Niyazov, L. M. Qin, F. Sabatié, S. Tkachenko, L. B. Weinstein, J. Yun, Et Al., Clas Collaboration

Physics Faculty Publications

Spin transfer from circularly polarized real photons to recoiling hyperons has been measured for the reactions →γ + p → K+ + →Λ and →γ+p → K+ + →Σ0. The data were obtained using the CEBAF Large Acceptance Spectrometer (CLAS) detector at the Jefferson Lab for center-of-mass energies W between 1.6 and 2.53 GeV, and for -0.85 < cos θc.m.K+ < +0.95. For the Λ, the polarization transfer coefficient along the photon momentum axis, Cz, was found to be near unity for a wide range of energy and kaon production angles. The associated transverse polarization coefficient Cx is smaller than Cz by a roughly …

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Measurement Of Coherent ɸ-Meson Photoproduction From The Deuteron At Low Energies, M. J. Amaryan, H. Bagdasaryan, S. Bültmann, S. L. Careccia, K. V. Dharmawardane, G. E. Dodge, G. Gavalian, N. Guler, C. E. Hyde-Wright, A. V. Klimenko, S. E. Kuhn, S. Tkachenko, L. B. Weinstein, Et. Al., Clas Collaboration Jan 2007

Measurement Of Coherent ɸ-Meson Photoproduction From The Deuteron At Low Energies, M. J. Amaryan, H. Bagdasaryan, S. Bültmann, S. L. Careccia, K. V. Dharmawardane, G. E. Dodge, G. Gavalian, N. Guler, C. E. Hyde-Wright, A. V. Klimenko, S. E. Kuhn, S. Tkachenko, L. B. Weinstein, Et. Al., Clas Collaboration

Physics Faculty Publications

The cross section and decay angular distributions for the coherent ɸ-meson photoproduction on the deuteron have been measured for the first time up to a squared four-momentum transfer t = (pᵧ - pɸ)2 =-2 GeV2/c2, using the CLAS detector at the Thomas Jefferson National Accelerator Facility. The cross sections are compared with predictions from a rescattering model. In a framework of vector meson dominance, the data are consistent with the total ɸ-N cross section σɸN at about 10 mb. If vector meson dominance is violated, a larger σɸN is possible by introducing a …

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Reactive Oxygen Emission From Microwave Discharge Plasmas, S. Popovic, M. Rašković, S. P. Kuo, L. Vuskovic Jan 2007

Reactive Oxygen Emission From Microwave Discharge Plasmas, S. Popovic, M. Rašković, S. P. Kuo, L. Vuskovic

Physics Faculty Publications

Metastable oxygen atoms and molecules have received increased interest because of their function in surface modification, bio-decontamination and many other industrial applications, in addition to the role in the upper atmospheric layer chemistry. We review work on production and detection of metastable oxygen and we describe our experiments, including the development of techniques for measurement of metastable molecular oxygen. We show that either metastable oxygen molecules or metastable oxygen atoms can be produced in large quantities in electrical discharges, carefully tailored to promote the required kinetics. Although the two species may coexist, colder discharge regimes favor production of molecules, while …

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Form Factors And Wave Functions Of Vector Mesons In Holographic Qcd, Hovhannes R. Grigoryan, Anatoly V. Radyushkin Jan 2007

Form Factors And Wave Functions Of Vector Mesons In Holographic Qcd, Hovhannes R. Grigoryan, Anatoly V. Radyushkin

Physics Faculty Publications

Within the framework of a holographic dual model of QCD, we develop a formalism for calculating form factors of vector mesons. We show that the holographic bound states can be described not only in terms of eigenfunctions of the equation of motion, but also in terms of conjugate wave functions that are close analogues of quantum-mechanical bound state wave functions. We derive a generalized VMD representation for form factors, and find a very specific VMD pattern, in which form factors are essentially given by contributions due to the first two bound states in the Q2 -channel. We calculate electric …

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Plasma Treatment Of Bulk Nb Surface In The Ar/Cl2 Discharge, M. Rašković, L. Vuskovic, S. Popovic, A.-M. Valente-Feliciano, L. Phillips Jan 2007

Plasma Treatment Of Bulk Nb Surface In The Ar/Cl2 Discharge, M. Rašković, L. Vuskovic, S. Popovic, A.-M. Valente-Feliciano, L. Phillips

Physics Faculty Publications

The preparation of the cavity walls has been one of the major challenges in the superconducting radio-frequency (SRF) accelerator technology. Therefore, constant research and development effort is devoted to develop surface preparation processes that will improve roughness and lower the level of impurities, like hydrogen or oxygen, embedded in bulk Nb, having in the same time reasonable etching rates. Plasma based surface modification provides an excellent opportunity to achieve these goals. We present Ar/Cl2 discharge treatment of bulk Nb where we achieved etching rates comparable to the rates obtained with the electropolishing method without introducing impurities in Nb. The …

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Cascade Production In The Reactions 𝛾p → K⁺ K⁺(X) And 𝛾p → K⁺K⁺ Π⁻⁻(X), M. J. Amaryan, H. Bagdasaryan, S. Bültmann, S. L. Careccia, K. V. Dharmawardane, G. E. Dodge, G. Gavalian, N. Guler, C. E. Hyde-Wright, N. Kalantarians, A. Klein, S. E. Kuhn, M. R. Niroula, S. Tkachenko, L. B. Weinstein, J. Zhang, Et Al., Clas Collaboration Jan 2007

Cascade Production In The Reactions 𝛾p → K⁺ K⁺(X) And 𝛾p → K⁺K⁺ Π⁻⁻(X), M. J. Amaryan, H. Bagdasaryan, S. Bültmann, S. L. Careccia, K. V. Dharmawardane, G. E. Dodge, G. Gavalian, N. Guler, C. E. Hyde-Wright, N. Kalantarians, A. Klein, S. E. Kuhn, M. R. Niroula, S. Tkachenko, L. B. Weinstein, J. Zhang, Et Al., Clas Collaboration

Physics Faculty Publications

Photoproduction of the cascade resonances has been investigated in the reactions γp → K + K +(X) and γp → K + K + π −(X). The mass splitting of the ground state (Ξ−,Ξ0) doublet is measured to be 5.4 ± 1.8 MeV/c2, consistent with existing measurements. The differential (total) cross sections for the Ξ− have been determined for photon beam energies from 2.75 to 3.85 (4.75) GeV and are consistent with a production mechanism of Y∗→K+Ξ− through a t-channel process. The reaction γp→K+K+π−[Ξ0] has also been investigated to …

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Cross Sections For The 𝛾p -> K*⁰ Σ⁺ Reaction At E𝛾 = 1.7-3.0 Gev, M. Amarian, H. Bagdasaryan, S. Bültmann, S. L. Careccia, G. E. Dodge, G. Gavalian, N. Guler, C. E. Hyde-Wright, A. Klein, A. V. Klimenko, S. E. Kuhn, M. R. Niroula, S. Tkachenko, L. B. Weinstein, J. Zhang, Et Al., The Clas Collaboration Jan 2007

Cross Sections For The 𝛾p -> K*⁰ Σ⁺ Reaction At E𝛾 = 1.7-3.0 Gev, M. Amarian, H. Bagdasaryan, S. Bültmann, S. L. Careccia, G. E. Dodge, G. Gavalian, N. Guler, C. E. Hyde-Wright, A. Klein, A. V. Klimenko, S. E. Kuhn, M. R. Niroula, S. Tkachenko, L. B. Weinstein, J. Zhang, Et Al., The Clas Collaboration

Physics Faculty Publications

Differential cross sections for the reaction 𝛾p→ K*0Σ+ are presented in the photon energy range of 1.7 to 3.0 GeV. The K*0 was detected by its decay products, K+π−, in the Continuous Electron Beam Accelerator Facility's large acceptance spectrometer (CLAS) detector at the Thomas Jefferson National Accelerator Facility. These data are the first K*0 photoproduction cross sections ever published over a broad range of angles. Comparison with a theoretical model based on the vector and tensor K∗-quark couplings shows good agreement with the data, except at forward angles, suggesting that …

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Experimental Study Of Exclusive ²H(E,E'P)N Reaction Mechanisms At High Q², S. E. Kuhn, M. J. Amaryan, H. Bagdasaryan, M. Bektasoglu, S. L. Careccia, K. V. Dharmawardane, G. E. Dodge, N. Guler, C. E. Hyde-Wright, H. G. Juengst, N. Kalantarians, A. Klein, M. R. Niroula, R. A. Niyazov, S. Tkachenko, L. B. Weinstein, J. Zhang, Et. Al., Clas Collaboration Jan 2007

Experimental Study Of Exclusive ²H(E,E'P)N Reaction Mechanisms At High Q², S. E. Kuhn, M. J. Amaryan, H. Bagdasaryan, M. Bektasoglu, S. L. Careccia, K. V. Dharmawardane, G. E. Dodge, N. Guler, C. E. Hyde-Wright, H. G. Juengst, N. Kalantarians, A. Klein, M. R. Niroula, R. A. Niyazov, S. Tkachenko, L. B. Weinstein, J. Zhang, Et. Al., Clas Collaboration

Physics Faculty Publications

The reaction 2H(e,e(')p)n has been studied with full kinematic coverage for photon virtuality 1.75 < Q2< 5.5 GeV2. Comparisons of experimental data with theory indicate that for very low values of neutron recoil momentum (pn< 100 MeV/c) the neutron is primarily a spectator and the reaction can be described by the plane-wave impulse approximation. For 100 < pn< 750 MeV/c, proton-neutron rescattering dominates the cross section, while Delta production followed by the NΔ → NN transition is the primary contribution at higher momenta.

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Effects Of Combined Exposure To Ethanol And Ionizing Radiation On The Antioxidant Status Of In Vitro And In Vivo Models, Joshua Ogony Jan 2007

Effects Of Combined Exposure To Ethanol And Ionizing Radiation On The Antioxidant Status Of In Vitro And In Vivo Models, Joshua Ogony

Doctoral Dissertations

"Ethanol and ionizing radiation exposure are independently known to cause tissue damage through various mechanisms. Non-enzymatic and enzymatic metabolism of ethanol, the latter via the cytochrome P₄₅₀2E1-dependent pathway, produces free radicals which deplete cellular glutathione (GSH). Ionizing radiation exposure has been shown to induce lipid peroxidation, DNA damage, protein oxidation, and GSH depletion, as well. It was postulated that initial exposure to ethanol, followed by ionizing radiation, would result in heightened oxidative stress. The in vitro model used in this investigation was HepG2 cells (human hepatocellular liver carcinoma cell line), while the in vivo model was Cd-1 mice"--Abstract, page iii.

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An Investigation Of Lead And Other Metal Contaminants In The Sediments Of Clearwater Lake, Missouri, Gary W. Krizanich Jan 2007

An Investigation Of Lead And Other Metal Contaminants In The Sediments Of Clearwater Lake, Missouri, Gary W. Krizanich

Doctoral Dissertations

"The purpose of this investigation is to characterize the spatial and temporal distribution and concentration of trace metals in sediments of Clearwater Lake. Understanding how trace metals are released to and transported in aquatic environments is important to the overall understanding of the impacts of mining on the natural environment. The main focus of this research will be on historic sedimentation within Clearwater Lake, which may act as a sink where mining related trace metals are stored. Because of their high preservation rates in basins, sediments can provide detailed chronostratigraphic histories of trace metal inputs in lakes. Sediment records can …

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Impacts Of Acid Mine Drainage On Carbon Cycling In Receiving Streams, Ernest W. Fonyuy Jan 2007

Impacts Of Acid Mine Drainage On Carbon Cycling In Receiving Streams, Ernest W. Fonyuy

Doctoral Dissertations

"Field and laboratory investigations of acid mine drainage (AMD) contaminated and uncontaminated waters were conducted in order to determine and model processes and reaction mechanisms that control dissolved inorganic carbon (DIC) transformation and shifts in isotope ratio of DIC (Δ¹³CDIC). The results show that AMD caused variable pH changes, overall decreases in Fe²⁺, alkalinity, and DIC, and increases in (Δ¹³CDIC) in receiving streams. AMD caused more than 50 to > 98% seasonal DIC loss in stream water through CO₂ degassing. High DIC losses corresponded to high Fe²⁺ and lower or no HCO₃⁻ in the water samples, because …

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Multiplicative Renormalization Method For Orthogonal Polynomials, Suat Namli Jan 2007

Multiplicative Renormalization Method For Orthogonal Polynomials, Suat Namli

LSU Doctoral Dissertations

To study the orthogonal polynomials, Asai, Kubo and Kuo recently have developed the multiplicative renormalization method. Motivated by infinite dimensional white noise analysis, it is an alternative to the computational part of the classical Gram-Schmidt process to find the orthogonal polynomials for a given measure. Instead of finding the orthogonal polynomials recursively as described in the Gram-Schmidt process, one analyzes different types of generating functions systematically in order to obtain polynomials after power series expansion. This work also produces the Jacobi-Szego parameters easily and paves the way for the study of one-mode interacting Fock spaces related to these parameters. They …

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