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Solid-Phase Synthesis Of Asymmetrically Substituted Phthalocyanines, Sultan Sibel Erdem Jan 2008

Solid-Phase Synthesis Of Asymmetrically Substituted Phthalocyanines, Sultan Sibel Erdem

LSU Doctoral Dissertations

Phthalocyanines (Pcs) are excellent candidates for use as fluorophores for near-infrared (near-IR) fluorescent tagging of biomolecules and as photodynamic therapy (PDT) agents. Synthesis of Pcs with asymmetrical substitution on the periphery is often difficult due to the problems during the purification of the Pc mixtures obtained. The objective of this project is to design and synthesize chemically robust near-IR fluorophores for bioanalytical applications and to develop new synthetic methods for rapid synthesis of the target compounds. A novel synthetic route was developed utilizing a hydrophilic, polyethylene glycol-based (PEG) support with different types of linkers. The Pcs were functionalized with either …

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The Use Endocrine Markers To Predict And Monitor Performance In Strengh [Sic] And Power Activities, Jason B. Winchester Jan 2008

The Use Endocrine Markers To Predict And Monitor Performance In Strengh [Sic] And Power Activities, Jason B. Winchester

LSU Doctoral Dissertations

Hormones are typically considered to be chemical messengers, which are designed to be released from specific cells where they are carried to their target tissues for binding to receptors. It is this binding of a hormone molecule to its specific receptor which allows for an action to occur (Hadley and Levine 2006). Testosterone is the predominant androgen in the majority of mammalian species and is largely responsible for regulation of reproduction and maintenance of sexual function. In addition, in adult mammals, T has multiple other roles including the growth of muscle and bone, hematopoesis, blood coagulation, development and regulation of …

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Toward An Effective And Humane Counterinsurgency, Adam Patrick Shilling Jan 2008

Toward An Effective And Humane Counterinsurgency, Adam Patrick Shilling

LSU Doctoral Dissertations

Preliminary research isolated a set of thirteen candidate principles that military officers need to understand to conduct effective and humane counterinsurgency. A meta-synthesis of eight classical theorists of counterinsurgency sought support for and consensus on these principles and discovered considerable consensus on all of them. Therefore, this set could be considered a “classical” model of counterinsurgency for use in counterinsurgency campaign planning. The contemporary global political environment is very different from that the classical theorists faced. Therefore, additional research attempted to understand the changes in the environment and in the nature of insurgency to determine the changes necessary to update …

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Matrix-Assisted Laser Desorption/Ionization Mass Spectrometry For The Analysis Of Collected Bioaerosols, Alton John Dugas Jan 2008

Matrix-Assisted Laser Desorption/Ionization Mass Spectrometry For The Analysis Of Collected Bioaerosols, Alton John Dugas

LSU Doctoral Dissertations

The goal of this dissertation was to demonstrate collection, detection and identification of microorganisms from bioaerosols using offline matrix-assisted laser desorption/ionization mass spectrometry (MALDI-MS) for the analysis of proteins. MALDI-MS intact bacteria techniques were adapted for use with an orthogonal MALDI quadrupole-time-of-flight mass spectrometer. Results indicate the instrument is capable of analyzing intact whole-cells. The first phase was to evaluate three bioaerosol samplers, an Andersen N6 single-stage impactor (AI), a cyclone impactor, and a vacuum filter system. The samplers collected test bioaerosols using a constructed bioaerosol exposure chamber (BEC). The BEC allowed all three samplers to operate in parallel. Each …

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Biotransformation Of Organic Wood Preservatives By Micro-Organisms, Diana Nasirumbi Obanda Jan 2008

Biotransformation Of Organic Wood Preservatives By Micro-Organisms, Diana Nasirumbi Obanda

LSU Doctoral Dissertations

Wood products are treated with biocides to prevent biodegradation by bacteria, fungi, and insects. Much attention is being directed towards testing of metal-free organic preservative systems. The major disadvantage of organics is that they are biotransformed by micro-organisms in soil and wood. This study explored the biotransformation of the fungicide tebuconazole by a bacteria species (Pseudomonas fluorescens), the mold (Trichoderma harzianum), the white rot fungus (Phanerochaete chrysosporium) and the brown rot (Meruliporia incrassata). After incubation of cultures spiked with tebuconazole, samples were analyzed for chemical remaining and metabolites. M. incrassata, T. harzianum, and the bacterium all cleaved the 1, 2, …

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Characterization And Comparison Of Cell Frequency, Growth, And Multipotential Differentiation Of Adult Mesenchymal Stromal Cells Derived From Equine Bone Marrow And Adipose Tissue, Martin Andreas Vidal Jan 2008

Characterization And Comparison Of Cell Frequency, Growth, And Multipotential Differentiation Of Adult Mesenchymal Stromal Cells Derived From Equine Bone Marrow And Adipose Tissue, Martin Andreas Vidal

LSU Doctoral Dissertations

Equine bone marrow-derived mesenchymal stromal cells (MSCs) and adipose tissue-derived stromal cells (ASCs) were compared for frequency within their respective tissues, cell doubling characteristics and differentiation multipotential in culture based on histochemical staining and compositional analysis. Equine MSCs and ASCs from young adult horses were harvested and isolated from sternal bone marrow and supragluteal subcutaneous adipose tissue, respectively, and grown up to passage 10 (P10) to determine cell doubling characteristics. Limit dilution assays were performed on primary and passaged (P2, P4) MSCs and ASCs to determine the frequency of colony forming units with a fibroblastic phenotype (CFU-F), and the frequency …

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Fabrication And Evaluation Of Specialty Nonwoven Materials, Nan Jiang Jan 2008

Fabrication And Evaluation Of Specialty Nonwoven Materials, Nan Jiang

LSU Doctoral Dissertations

The present work is to develop multifunctional materials with high performance on chemical absorption, adsorption and on acoustic absorption and insulation using natural fiber nonwovens via carbonization and activation. Evaluation of these textile materials includes tensile strength, thermogravimetric analysis, sound absorption and transmission loss, scanning electronic microscopy and surface properties. Carbonization of cotton nonwoven was carried out in a high temperature oven with nitrogen between 300 °C and 500 °C. The physical activation was undertaken using CO2. The N2 adsorpton isotherm curves of the cotton nonwoven showed the presence of micropores and macropores. High BET surface area and average pore …

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The Initial Reliability And Construct Validity Of The Autism Spectrum Disorder-Diagnostic (Asd-Dc) In Children, Melissa Luke Gonzalez Jan 2008

The Initial Reliability And Construct Validity Of The Autism Spectrum Disorder-Diagnostic (Asd-Dc) In Children, Melissa Luke Gonzalez

LSU Doctoral Dissertations

The aim of the present study was to examine the reliability and construct validity of a newly developed assessment scale designed to identify autism spectrum disorders in children: Autism Spectrum Disorder-Diagnostic for Children (ASD-DC). Participants were parents and caregivers of children between ages 2 and 16 years, who are typically developing or developmentally delayed. Participants were asked to complete several rating scales including the ASD-DC, a DSM-IV-TR/ICD-10 checklist, the Matson Evaluation of Social Skills in Youngsters (MESSY), and the Behavioral Assessment System for Children, Version 2 (BASC-2). In Study 1, the test-retest, inter-rater, and inter-item reliabilities of the ASD-DC was …

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The Gallant Six Hundred: Performing The Light Brigade Into A Heroic Icon, Elizabeth Carrick Cawns Jan 2008

The Gallant Six Hundred: Performing The Light Brigade Into A Heroic Icon, Elizabeth Carrick Cawns

LSU Doctoral Dissertations

History is not so much what actually happened as how we have received and disseminated what happened. This reception and dissemination take place through a variety of media, many of which are not the purview of the traditional historian. It is in the trifles of daily life that we find the patterns of cultural norms – the ethos of the society that is as unnoticed by that society as the air it breathes. Society makes choices that affect the future based on what has been disseminated, rather than on the original event. This is especially true of such military disasters …

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The Effects Of Cross-Age Mentoring In An Online Collaborative Environment, Gail Lorraine Johnson Jan 2008

The Effects Of Cross-Age Mentoring In An Online Collaborative Environment, Gail Lorraine Johnson

LSU Doctoral Dissertations

This mixed method research was designed to examine the effects of cross-age mentoring in an inter-institutional online learning community. The research questions focused on the impact of mentoring on high school students’ confidence in their information seeking skills, perceptions of their information seeking standards, and the application of these standards to an information seeking task. Also of interest was the dialogic interaction between the students at the two sites, the impact of the facilitator on the process, and the university students’ perceptions about their experience. The participants included 26 students (mentees) enrolled in an American history class at a rural …

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Lattice Boltzmann Modeling For Mass Transport Equations In Porous Media, Borja Servan Camas Jan 2008

Lattice Boltzmann Modeling For Mass Transport Equations In Porous Media, Borja Servan Camas

LSU Doctoral Dissertations

The aim of this dissertation is to extend the lattice Boltzmann method (LBM) to cope with parameter heterogeneity and anisotropy in mass transport equations in porous media, as well as investigating the stability and accuracy. Although the LBM is a well known and effective numerical method to solve fluid flows, LBM has not been extensively applied to mass transport equations in porous medium flow yet, and only a few works can be found on improving LBM to cope with mass transport equations other than the diffusion and advection-diffusion equations. One of the reasons why LBM has not been extensively used …

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The Rhetorical Myth Of The Athlete As A Moral Hero: The Implications Of Steroids In Sport And The Threatened Myth, Karen L. Hartman Jan 2008

The Rhetorical Myth Of The Athlete As A Moral Hero: The Implications Of Steroids In Sport And The Threatened Myth, Karen L. Hartman

LSU Doctoral Dissertations

This research analyzes changes in the rhetoric of a sustaining myth in order to better assess what happens when a myth is threatened. By examining American sport and its current struggle to withstand the widespread use of steroids, the author investigates how public discourse about the scandal turns athletes from mythical heroes to cheaters. The author begins by explicating the rhetorical construction of the athlete as a moral hero in America and how this myth is perpetuated today. The author then examines how steroids threaten the myth of the moral athlete and uses Major League Baseball as a case study …

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Apocalypse South: Judgment, Cataclysm, And Resistance In The Regional Imaginary, Anthony Hoefer Jan 2008

Apocalypse South: Judgment, Cataclysm, And Resistance In The Regional Imaginary, Anthony Hoefer

LSU Doctoral Dissertations

This project investigates manifestations of Apocalypse in selected works of southern fiction, each of which simultaneously draws upon the cosmology of southern evangelical Protestantism and disrupts that cosmology’s power to govern the discourses of race, class, and gender in the U.S. South. Apocalypse South proposes that invocations of the Apocalypse are signs of deferred meaning—of hidden histories of undifferentiation, hybridity, and contradiction which defy the prevailing discourses that configure social relationships in southern spaces and places. Southern religious culture maps Apocalypse onto the boundaries of race, class, and gender and imparts catastrophic consequences to their violations. However, the works investigated …

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Teaching Presence: A Focus On The Instructor's Role In Online Collaborative Learning, Keisha Smith Dubuclet Jan 2008

Teaching Presence: A Focus On The Instructor's Role In Online Collaborative Learning, Keisha Smith Dubuclet

LSU Doctoral Dissertations

The use of e-learning has been extended beyond simply providing access to information to providing the ability to learn collaboratively via an interactive learning environment. The ability to create an online collaborative and interactive environment is a challenge. This study strove to examine the most effective design and facilitative strategies for fostering student learning and participation in hopes to make design and implementation of online discussions easier and more efficient for teachers. The primary goal of this study was to understand how the degree of instructor presence influenced students’ perception of learning and how students engaged in deeper levels of …

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Essay 1: Does Ownership Structure Matter? Essay 2: Asset Sale In Mutual Fund Industry, Fan Chen Jan 2008

Essay 1: Does Ownership Structure Matter? Essay 2: Asset Sale In Mutual Fund Industry, Fan Chen

LSU Doctoral Dissertations

The dissertation studies two aspects of the U.S. registered investment companies. The first essay analyzes the ownership and organizational structure aspect while the second essay investigates the restructure events of those investment companies. We find sellers from mutual fund asset sales are mainly financial conglomerates. Funds under management of those conglomerates experience poor performance during the period prior to asset sales. On the other hand, acquirers are generally highly focused mutual fund companies. Funds acquired by these focused entities experience improvement in both fund performance and operational efficiency. From the analysis of organizational structure, funds managed by focused mutual fund …

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The Perils And Empowerments Of Mountain Literacies: Reading Loss And Shifting Identities In Appalachian Memoirs And Novels, Erica Abrams Locklear Jan 2008

The Perils And Empowerments Of Mountain Literacies: Reading Loss And Shifting Identities In Appalachian Memoirs And Novels, Erica Abrams Locklear

LSU Doctoral Dissertations

This dissertation analyzes the literary portrayal of literacy events in memoirs and novels written by Appalachian women during the twentieth and twenty-first centuries. Drawing from contemporary literacy scholarship, my project engages several definitions of the term "literacy," including theories defining it as a technical skill, a social act, cultural knowledge, or a potent form of ideological power. In a region historically (and often inaccurately) stigmatized as illiterate, "literacy" is a loaded term, a concept doubly associated with cultural pride and with cultural loss. By applying literacy theories to Appalachian literature, I analyze the identity conflicts literacy attainment causes for several …

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The Synthesis Of Water Soluble N-Acyl Chitosan Derivatives For Characterization As Antibacterial Agents, Lakia Monique Champagne Jan 2008

The Synthesis Of Water Soluble N-Acyl Chitosan Derivatives For Characterization As Antibacterial Agents, Lakia Monique Champagne

LSU Doctoral Dissertations

Currently, natural polysaccharides are being utilized increasingly in the markets because they exhibit biodegradability, biocompatibility, versatility, and are found abundant in nature. The diversity of natural polysaccharides provides the chemist with a broad spectrum of raw materials that can be used in many biological applications. Chitosan is a natural polysaccharide that possesses excellent biological properties. It has been recognized for its antibacterial activity, in that it is destructive towards the bacterium Escherichia coli (E. coli) and Staphylococcus aureus (S. aureus). The antibacterial property of chitosan can be enhanced by changing the hydrophobic/hydrophilic nature of the polysaccharide backbone. This research entails …

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Internet Use And Environmental Justice: An Exploratory Study, Jane Catherine Dailey Jan 2008

Internet Use And Environmental Justice: An Exploratory Study, Jane Catherine Dailey

LSU Doctoral Dissertations

My study examined how inner-city adults perceive and experience the Internet as a civic engagement tool, and if they view the Internet as a tool for environmental advocacy. Research shows a consistent divide between those with Internet access and those without. Individuals living in low-income minority communities are the least likely groups to be Internet connected. Consequently, the Internet could further separate historically marginalized communities from important government and social resources rather than bringing them closer. Qualitative research methods were used to reveal socially-constructed perceptions of the Internet as a civic engagement tool in the inner city. Grounded theory techniques …

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Cryopreservation Of Adipose Derived Adult Stem Cells And Multidimensional Cell Sheets, Sreedhar Thirumala Jan 2008

Cryopreservation Of Adipose Derived Adult Stem Cells And Multidimensional Cell Sheets, Sreedhar Thirumala

LSU Doctoral Dissertations

Human adipose tissue provides a uniquely abundant and accessible source of adult stem cells. In response to chemical, hormonal or structural stimuli, these human adipose-derived adult stem (ASCs) cells can differentiate along multiple lineage pathways, including adipocytes, chondrocytes, myocytes, neurons and osteoblasts. Successful cryopreservation of scientifically and commercially important ASCs would revolutionize the tissue engineering and regenerative medicine industry. In this research, we have investigated the water transport phenomenon during freezing of several passages of adipose derived adult stem cells and generated the membrane permeability parameters in the presence and absence of cryoprotective agents. These measured permeability parameters were then …

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Thermomechanical Interaction Analysis Of Bodies Subjected To Oscillatory Heat Source, Jun Wen Jan 2008

Thermomechanical Interaction Analysis Of Bodies Subjected To Oscillatory Heat Source, Jun Wen

LSU Doctoral Dissertations

Surface heating by application of a moving heat source is a common problem in most manufacturing processes as well as in many tribological applications. The existing literature on studies of moving heat source problems primarily concentrates on unidirectional moving heat sources. Yet, a more complete analysis requires understanding of thermal behavior of bodies in relative sliding contacts subjected to oscillatory heat sources and thermomechanical interaction. In this dissertation, two analytical models are developed for rapid evaluation of the transient temperature in solids undergoing oscillatory heat source. In the first model, an analytical technique is presented to treat oscillatory heat source …

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A Longitudinal Study Of Married Women's Probability Of Being Housewives In Reforming Urban China, Chiung-Yin Hu Jan 2008

A Longitudinal Study Of Married Women's Probability Of Being Housewives In Reforming Urban China, Chiung-Yin Hu

LSU Doctoral Dissertations

This study examines married women’s employment status and the factors associated with their being full-time housewives between 1989 and 2004 in urban China. I argue that the transition from a command economy to a market-oriented economy since the early 1980s has had negative impacts on married women’s labor force participation. Using six waves of the Chinese Health and Nutrition Survey (1989, 1991, 1993, 1997, 2000, and 2004), I find that the percentages of full-time housewives in urban China tripled in just 15 years, and the largest amount of growth occurred in the most recent period. Regression analyses confirm that married …

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The Fusion Model Of Instructional Design: A Proposed Model For Faculty Development Programs In Technology Integration, Lori C. Soule Jan 2008

The Fusion Model Of Instructional Design: A Proposed Model For Faculty Development Programs In Technology Integration, Lori C. Soule

LSU Doctoral Dissertations

University faculty are increasingly challenged to integrate technology into their teaching to meet the needs of technology-savvy students today. The purpose of this dissertation is to introduce and examine an instructional design model, the Fusion Model of Instructional Design, for designing and implementing more effective faculty development programs in technology integration. The model builds on positive aspects of participatory design (Vincini, 2001), rapid prototyping (Tripp & Bichelmeyer, 1990), and Keller’s (1983) ARCS model of motivation. Key characteristics of the Fusion Model are participation of early adopters in the design and implementation of training, recursive training of early adopters first and …

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Concentration Of Phosphorylated Proteins Using Modified Pmma Microanalytical Devices, Jowell Guerra Bolivar Jan 2008

Concentration Of Phosphorylated Proteins Using Modified Pmma Microanalytical Devices, Jowell Guerra Bolivar

LSU Doctoral Dissertations

This work describes the application of PMMA-based microanalytical devices for the affinity-type preconcentration of posttranslational modified proteins (PTMs). The choice of poly(methyl methacrylate), PMMA, is based on its biocompatibility, its functional methyl ester group for potential modification, and its extensive applications to create biological microelectromechanical systems (BioMEMS). Developing methodologies for preconcentration of PTMs is important for cancer diagnosis due to PTMs’ influence in the regulatory mechanism underlying the early stage of apoptosis or regulated cell death. Towards this goal, nitroavidin which can reversibly binds to biotin (and biotinylated proteins), was prepared using reported procedure and was characterized using several techniques …

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Elements Of Mythmaking In Witness Accounts Of Colonial Piracy, Plamen Ivanov Arnaudov Jan 2008

Elements Of Mythmaking In Witness Accounts Of Colonial Piracy, Plamen Ivanov Arnaudov

LSU Doctoral Dissertations

Focusing on historical accounts (1684-1734) by English, French, and Spanish witnesses, this dissertation establishes a continuity in fictionalized representations of anti-heroic pirates from the buccaneering period to the Golden Age of Piracy. Informed by history, literary, myth, and performance theory, the analysis identifies significant distortions in reports by observers and participants. The distortions that pertain to mythmaking patterns are classified and analyzed further. Conflicting and ambivalent representations of the pirate as an anti-hero are resolved through the positing of a literary scapegoat hypothesis drawing from René Girard and Joseph Roach. While demonstrating mythical archetypes at work in the construction of …

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Multimedia Mathematics Intervention For Math-Delayed Middle School Students, Lisa L. Stokes Jan 2008

Multimedia Mathematics Intervention For Math-Delayed Middle School Students, Lisa L. Stokes

LSU Doctoral Dissertations

The purpose of this study is to determine if the Sharpening Math Skills Lab technology-mediated mathematics instructional practices for math-delayed middle school students have positive effects on their mathematics achievement and spatial visualization ability and to gauge student engagement in learning, implementation of the principles of instructional design, and attitudes toward mathematics instruction. The results of a recent meta-analysis report a range of significantly positive to significantly negative effect sizes which establish a need for further evaluation of academic achievement utilizing technology-mediated mathematics programs at the middle school level (Slavin, Lake, & Groff, 2007). The literature (Moreno & Mayer, 2000) …

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Synthesis And Surface Characterization Of Silica-Polypeptide Composite Particles, Erick Isael Soto-Cantu Jan 2008

Synthesis And Surface Characterization Of Silica-Polypeptide Composite Particles, Erick Isael Soto-Cantu

LSU Doctoral Dissertations

The synthesis and sequential surface characterization of silica-polypeptide composite particles is described. Nearly monodisperse colloidal silica cores were obtained by the alkaline hydrolysis of tetraethyl orthosilicate (TEOS). The hydrodynamic radius can be easily controlled in the range of ƒî 20-140 nm by the water/TEOS ratio in the starting reaction mixture. The surface of the synthesized silica cores was further passivated/functionalized (P/F) by a mixture of (3-aminopropyl) trimethoxysilane (APS) and methyl-trimethoxysilane (MTMS). The amino groups were quantified using UV-Vis spectrometry after reaction with ninhydrin. The use of zeta potential measurements of the P/F silica particles at low pH is presented as …

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Phonemic Awareness And Sight Word Reading In Toddlers, Alicia Tonya Mcinnis Jan 2008

Phonemic Awareness And Sight Word Reading In Toddlers, Alicia Tonya Mcinnis

LSU Doctoral Dissertations

This study investigated emerging phonemic awareness skills and printed sight word recognition abilities in two-year-old toddlers using plain text and MorphoPhonic Face words on flash cards. MorphoPhonic Face words were used to determine if this learning process is enhanced when words are iconically represented to show the first sound and the word's meaning (purposefully creating idiosyncratic cues) using pictures superimposed into the letters. Sixteen (16) age-matched toddlers were assigned to alternate treatment groups and received exposure to both printed and MorphoPhonic pictured words three times weekly for six weeks. During each session, children were taught 16 sight words (8 in …

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Genetic And Mechanistic Analysis Of Heterochromatin Spreading In The Yeast S.Cerevisiae, Nithya Jambunathan Jan 2008

Genetic And Mechanistic Analysis Of Heterochromatin Spreading In The Yeast S.Cerevisiae, Nithya Jambunathan

LSU Doctoral Dissertations

RNA Polymerase III transcribed tRNA genes are implicated in a wide variety of chromosome organizational functions that includes the ability to act as a boundary to heterochromatic silencing. A tRNA gene has been shown to be a major component of the barrier that prevents spreading of silencing from the HMR locus to the downstream GIT1 gene on chromosome III in S.cerevisiae. Our results suggest that additional proteins are involved in maintaining the boundary function of this tRNA gene. Mutations or deletions of the genes coding for these additional proteins have been shown to either weaken the boundary or enhance silencing. …

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Redutive Dehalogenation Of Chlorinated Alkanes By Novel Bacteria At The Petroprocessor Of Louisiana Inc. Superfund Site, Jun Yan Jan 2008

Redutive Dehalogenation Of Chlorinated Alkanes By Novel Bacteria At The Petroprocessor Of Louisiana Inc. Superfund Site, Jun Yan

LSU Doctoral Dissertations

A reductively dehalogenating enrichment culture was established using chloroalkane-contaminated groundwater from the PetroProcessors of Louisiana, Inc. (PPI) Superfund site. Two novel, strictly anaerobic bacterial strains, designated as BL-DC-8 and BL-DC-9, were isolated from the enrichment culture. These strains represent the first bacteria known to anaerobically dehalogenate 1,2,3-trichloropropane, the degradation pathway of which was determined. Both strains could be cultured in completely defined basal medium and were also able to dehalogenate a variety of other vicinally chlorinated alkanes including 1,1,2,2-tetrachloroethane, 1,1,2-trichloroethane, 1,2-dichloroethane, and 1,2-dichloropropane via dichloroelimination reactions. Chlorinated alkanes containing only a single chlorine substituent (1-chloropropane, 2-chloropropane), chlorinated alkenes (tetrachloroethene, trichloroethene, …

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Heterogeneous Catalyzed Macromolecular Hydrogenations In Oscillating Systems, Alan Bussard Jan 2008

Heterogeneous Catalyzed Macromolecular Hydrogenations In Oscillating Systems, Alan Bussard

LSU Doctoral Dissertations

An examination of novel oscillatory (alternating gas and liquid phase) reactors and heterogeneous catalysts for multi-phase macromolecular reactions was carried out. A monolith-containing square die with Pd/Al2O3 catalysts was used to successfully hydrogenate poly(styrene) (PS). The inherent pulse behavior of the extruder was found to be sufficient to approach intrinsic kinetics at low polymer concentrations. At higher (10 wt% PS) concentrations, forced pulsing was shown to have a greater impact on observed reaction rates. Selectivity with this extruder-fed reactor was better than with a stirred tank in all cases, due to a more plug-flow-like residence time distribution. While accurate control …

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