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Parallel Molecular Dynamics Simulations Of Antimicrobial Peptides, Svetlana V. Oard Jan 2004

Parallel Molecular Dynamics Simulations Of Antimicrobial Peptides, Svetlana V. Oard

LSU Master's Theses

Molecular dynamics (MD) simulations of the wheat antimicrobial peptide â-purothionin were carried out in explicit water (~14,000 atoms) using an all-atom model. The structural properties of the peptide as a function of MD simulation, temperature, and presence of the mono- and divalent metal ions were investigated. The accuracy and scalability tests of the code Peach 3.8 for our system were performed on the Intel Xeon-based Linux cluster SuperHelix at Louisiana State University (LSU). The code showed the reliable accuracy and the parallel efficiency of 0.61 for ~14,000 particles on 16 processors. The microcanonical (MC) MD simulation of â-purothionin in water …

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The Fate Of Bifenthrin And Fipronil In Pine Bark Nursery Media, Russell Stanley Harris, Iii Jan 2004

The Fate Of Bifenthrin And Fipronil In Pine Bark Nursery Media, Russell Stanley Harris, Iii

LSU Master's Theses

Concerns over the adverse effects of pesticides on human health and the environment have led to the development of stricter pesticide regulations and the outright banning of many pesticides in the U.S. Bifenthrin and fipronil are important pesticides used in the nursery industry for the control of imported fire ants (Solenopsis invicta Buren, S. richteri Forel, and their hybrids) to meet the requirements of the Imported Fire Ant Quarantine. Nurseries typically use highly-organic media ("soilless" media) and little is known about the fate of these pesticides when used with these media. Our research measured the influence of irrigation frequency and …

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Photo-Control Of Dna Oligonucleotides With Cage Compounds, Bilal Ghosn Jan 2004

Photo-Control Of Dna Oligonucleotides With Cage Compounds, Bilal Ghosn

LSU Master's Theses

Many biochemical processes in which DNA and other nucleic acids participate are central to functions in both living cells and in molecular biology assays. While many compounds have been used to regulate the activity of DNA, these strategies are limited to the aqueous-based diffusion of the activator to the target DNA molecule. An improvement to the induction of DNA bioactivity is to move to a light-based modulation. This research demonstrates a light-based technique using a photo-cleavable cage compound to transiently inactivate DNA hybridization. Function can be restored with exposure to near-UV light, allowing for temporal control of DNA oligonucleotide (ODN) …

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Synthesis, Characterization And Tribological Behavior Of Nitrogen-Doped Chromium-Diamond-Like Carbon Nanocomposite Thin Films, Sunil Kumar Pal Jan 2004

Synthesis, Characterization And Tribological Behavior Of Nitrogen-Doped Chromium-Diamond-Like Carbon Nanocomposite Thin Films, Sunil Kumar Pal

LSU Master's Theses

Diamond-like carbon (DLC) films have been extensively studied for more than two decades due to their highly attractive properties. These films exhibit unique mechanical, chemical and electronic properties and thus, possess great potential for applications in tribology. However, two drawbacks in the DLC films are high level of internal stress developed during growth preventing deposition of thick films and low thermal stability. Synthesis of Me-DLC (Cr-DLC and N-doped Cr-DLC) presents a way to overcome these drawbacks. In the present study, DLC, Cr-DLC and N-doped Cr-DLC films were deposited on Si substrate using a hybrid Plasma assisted CVD/PVD process. Film characterization …

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State-Level Environmental Risk Perception: An Analysis Of 20 Comparative Risk Reports, Mandy Green Jan 2004

State-Level Environmental Risk Perception: An Analysis Of 20 Comparative Risk Reports, Mandy Green

LSU Master's Theses

Research was conducted to identify the states that compiled Comparative Risk Reports and the year in which the study was completed. The information relating to the type of committee that compiled the risk report and the final risk rankings was examined. State Comparative Risk Reports were collected for twenty states and the risk rankings that each state compiled were reviewed to determine which states ranked third generation environmental problems and the ranking that those problems were given. The risk reports compiled by each state were also used to determine which states ranked natural resource based problems and the ranking that …

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Mortality Of Pen-Raised White-Tailed Deer (Odocoileus Virginianus) Released On Three Areas In Louisiana, Barret Keith Fortier Jan 2004

Mortality Of Pen-Raised White-Tailed Deer (Odocoileus Virginianus) Released On Three Areas In Louisiana, Barret Keith Fortier

LSU Master's Theses

I monitored 60 radio-collared and tagged pen-raised white-tailed deer (Odocoileus virginianus) to ascertain mortality rates on three areas in Louisiana from April 2001 - April 2002. Two of 60 were not used in the analysis because mortality occurred from complications with darting and an affixed radio-collar. Study deer were exposed to legal hunting mortality only if they emigrated from the three study areas. Twenty deer were released to the wild on the Louisiana State University Deer Study Area (LSUDSA) (4,810 ha), where 9 of 20 (45%) suffered mortality. Harvest accounted for 56%, vehicles 22%, and other 22% of the mortality …

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Effects Of Family Violence And Parental Psychopathology On The Psychological Outcome Of Urban Adolescents Exposed To Community Violence, Shannon Self-Brown Jan 2004

Effects Of Family Violence And Parental Psychopathology On The Psychological Outcome Of Urban Adolescents Exposed To Community Violence, Shannon Self-Brown

LSU Doctoral Dissertations

Previous research has documented an association between adolescents’ exposure to community violence and a range of mental health problems. However, some violence-exposed youth maintain high levels of adaptive behavior and exhibit good psychological functioning. Thus, it appears that protective and/or risk factors are involved in the community violence-psychological outcome relation, which mitigate the conditions under which community violence exposure leads to adverse adolescent outcome. According to the ecological transactional model, protective and/or risk factors may exist within the family that influence adolescent outcome in response to community violence exposure. The purpose of this study was to delineate the relations among …

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Analysis Of Factors That Affect Responding In A Two-Response Chain In Children With Developmental Disabilities, Stephanie Ann Contrucci Kuhn Jan 2004

Analysis Of Factors That Affect Responding In A Two-Response Chain In Children With Developmental Disabilities, Stephanie Ann Contrucci Kuhn

LSU Doctoral Dissertations

Behaviors that are appropriate, inappropriate, or a combination of both can be linked together in a behavior chain. When the contingencies for one response change (e.g., reinforcement is withheld for the last response in the chain; the last response is reinforced even if it occurs without the other responses in the chain) or the environmental conditions change (e.g., access to the reinforcer is available independent of responding), the other responses in the chain may be affected. Little is known about these types of effects on behavior chains. Several operant processes may disrupt behavior chains. The purpose of this study was …

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Partitioned Pricing: Can We Always Divide And Prosper?, Bidisha Burman Jan 2004

Partitioned Pricing: Can We Always Divide And Prosper?, Bidisha Burman

LSU Doctoral Dissertations

Research on partitioned pricing suggests that separating the surcharges from the base price of the advertised product may lead to a more favorable effect on consumers' evaluation of the offer compared to a combined presentation of the base price and the surcharge. In this dissertation we propose that partitioned price presentation may not always result in positive outcomes vis-à-vis combined presentation of prices. We propose that consumers' need for cognition and the perceived reasonableness of the surcharge are likely to influence their evaluation of partitioned versus combined prices. Based on cue diagnosticity, Persuasion Knowledge Model, and Characterization-Correction Model we develop …

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An Original Composition Symphony No. 1 "Night Symphony" And An Analysis Of Selected Traditional And Non-Traditional Elements Of Harmony In Credo By Krzvsztof Penderecki, Aaron Edward Johnson Jan 2004

An Original Composition Symphony No. 1 "Night Symphony" And An Analysis Of Selected Traditional And Non-Traditional Elements Of Harmony In Credo By Krzvsztof Penderecki, Aaron Edward Johnson

LSU Doctoral Dissertations

The first part of this dissertation is an original composition Symphony No. 1 "Night Symphony." It is a three-movement work scored for large orchestra. Each of the three movements is subtitled with a descriptive aspect of a different part of the night: 1. Twilight, 2. Nocturne, and 3. Waning Darkness. The work is not a musical narrative of the night cycle and does not include night sounds. The subtitles are only meant to suggest the general mood I associate with particular stages of the night. The tempi of the movements fall into a fast-slow-fast arrangement. The outer movements are scored …

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Rates Of Molecular Evolution And Their Application To Neotropical Avian Biogeography, Christopher C. Witt Jan 2004

Rates Of Molecular Evolution And Their Application To Neotropical Avian Biogeography, Christopher C. Witt

LSU Doctoral Dissertations

The tempo of evolution and the causes of rate variation among lineages are central foci of evolutionary biology. I evaluated two hypothesized sources of variation in molecular evolutionary rate, and I applied a variable molecular clock to estimate the timescale of diversification in three families of Neotropical birds. First, I examined the phylogenetic evidence for molecular punctuated equilibrium, the hypothesis that speciation drives accelerated molecular evolution. Recent findings that rates of DNA evolution and speciation are linked implicate molecular punctuated equilibrium as an important cause of rate variation among lineages. I used phylogenetic simulations to test this reported link, and …

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William Faulkner And The Oral Text, Gregory Alan Borse Jan 2004

William Faulkner And The Oral Text, Gregory Alan Borse

LSU Doctoral Dissertations

The disjunction between the oral and the literate in the works of William Faulkner reveals the different ways these distinct modes of organization combine to structure a text. The oral in Faulkner's fiction makes its presence known not only as offset speech but also as a mode of action and narrative whose logic is conjunctive rather than disjunctive. According to the literate mode, a form organizes novelistic matter. According to the oral mode, forces that function as signs rather than organizers of their form rule the action and narrative. When the disjunction between the oral and the literate is so …

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The Myth Of Charismatic Leadership And Fantasy Rhetoric Of Crypto-Charismatic Memberships, Shaun Robert Treat Jan 2004

The Myth Of Charismatic Leadership And Fantasy Rhetoric Of Crypto-Charismatic Memberships, Shaun Robert Treat

LSU Doctoral Dissertations

This study will analyze the relationship between myth and the fantasy rhetoric of charismatic leadership by employing Fantasy Theme Analysis to examine the pervasive discourses invoking this enduring folk belief. Fantasies of the Charismatic Superhero are explored within the popular leadership treatises of successful “management gurus” and in our popular culture entertainments. The rhetorical visions of Stephen Covey’s “Principle-Centered Leadership,” Jim Collins’ “Level 5 Leadership,” and Manz and Sims' “SuperLeadership” are examined for their displacement of charismatic leadership in favor of the empowered crypto-charisma of self-leading memberships. Findings suggest “empowerment” rhetorics, like the rhetorical visions championed by many populist “gurus,” …

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Compelled To Compose: An Introduction To The Life And Music Of Paul Basler , With A Conductor's Analysis Of Missa Kenya, Gary Packwood Jan 2004

Compelled To Compose: An Introduction To The Life And Music Of Paul Basler , With A Conductor's Analysis Of Missa Kenya, Gary Packwood

LSU Doctoral Dissertations

The choral literature of Paul Basler and his style are relatively unexplored. While his style is not readily identifiable, particular characteristics can be understood in their appropriate genres and cultural contexts. The compositional style of Missa Kenya features great variety, incorporating twentieth century American ‘classical’ techniques, and those based solely on indigenous tradition. This document focuses on the life, influences, and music of Paul Basler, with particular attention to his composition, Missa Kenya. A conductor’s analysis and interpretational suggestions are also provided. Several interviews were conducted by email and in person with Paul Basler, and Ronald Burrichter, the conductor for …

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Synthesis, Structure, And Tribological Behavior Of Nanocomposite Dlc Based Thin Films, Varshni Singh Jan 2004

Synthesis, Structure, And Tribological Behavior Of Nanocomposite Dlc Based Thin Films, Varshni Singh

LSU Doctoral Dissertations

Diamond-like carbon (DLC) films possess a combination of attractive properties and have been largely employed to modify the tribological behavior of materials. Nanocomposite, metal-containing DLC films are the new generation of these coatings providing tremendous potential to modify and tailor their properties expanding their applications in the field of nanotechnology. The present study investigates nanoscale effects on the tribological behavior of composite nanostructured DLC-based films and functional coatings. Three aspects were studied: (i) effect of Cr interlayer on a functionally gradient substrate; (ii) nanoparticulate Cr-containing DLC (Cr-DLC) films; and (iii) nanocomposite multilayered Cr/DLC coatings. Intensified plasma assisted nitriding produced a …

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Effective Literacy Instruction In The Elementary Grades, Marie Laurent Bergeron Jan 2004

Effective Literacy Instruction In The Elementary Grades, Marie Laurent Bergeron

LSU Doctoral Dissertations

The purpose of this study was to identify elements present in effective literacy instruction, i.e., those elements that fostered reading, speaking, listening, thinking, writing, and metacognitive skills. By examining variables that promoted literacy acquisition and achievement, a detailed account resulted which described classroom practice as related to teacher beliefs, strategies, materials, and classroom climate. The primary method of qualitative analysis used for this study was the Developmental Research Sequence (DRS) Method (Spradley, 1980). Two classrooms with exemplary teachers were studied extensively. Data collection involved the use of primary sources (interviews, observations, and student and teacher work) and secondary sources (records, …

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Integrating A Technology-Enriched Curriculum: Ethno-Case Study, Juliette D. Angers Jan 2004

Integrating A Technology-Enriched Curriculum: Ethno-Case Study, Juliette D. Angers

LSU Doctoral Dissertations

The purpose of this qualitative study was to provide an examination of beliefs, context factors, and practices of exemplary teachers that lead to a technology-enriched curriculum. Three middle school teachers participated. Using both direct and participant observation the Spradley model was followed with three rounds of observations: (1) descriptive, (2) focused, and (3) selective. Interviews were conducted with open-ended questions and documents were collected from the parish website. This research provides: (1) up-to-date information on what and how educational technology is used today; and (2) information which gives other educators an understanding of what beliefs and context factors influence teachers …

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A Qualitative Exploration Of Students' Experiences With Tutorial Learning, Angela Alexander Jan 2004

A Qualitative Exploration Of Students' Experiences With Tutorial Learning, Angela Alexander

LSU Doctoral Dissertations

The purpose of this study is to explore how students perceive their tutorial learning experiences at the collegiate level in a campus-based center and to explore the personality preferences of the students who participate in tutoring, according to the Myers-Briggs Type Indicator (MBTI). The study is designed to address tutoring from the perspective of the tutee’s experiences and to allow them to tell their story of how tutoring impacted their academic experience. The following research questions guide this study: 1. What are students’ perceptions of their tutorial learning experiences? 2. Are students’ perceptions of their tutorial learning experiences related to …

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Molecular, Genetic And Physiological Characterization Of A Chlamydomonas Reinhardtii Insertional Mutant, James Edward,Iv Adams Jan 2004

Molecular, Genetic And Physiological Characterization Of A Chlamydomonas Reinhardtii Insertional Mutant, James Edward,Iv Adams

LSU Doctoral Dissertations

Photosynthetic microorganisms must acclimate to environmental conditions that may lead to photo-oxidative stress, such as low CO2 environments or high light intensities. Chlamydomonas reinhardtii, a unicellular, green alga with a Carbon Concentrating Mechanism (CCM), effectively accumulates inorganic carbon (Ci) to levels higher than external concentrations. The CCM concentrates inorganic carbon around Rubisco to increase the CO2 fixation efficiency of C. reinhardtii. Photorespiration, the water-water cycle, the xanthophyll cycle, and the CCM are adaptations that also prevent the over-reduction of photosystems and thus photoinhibition by dissipating the energy from the absorption of excess photons. In an effort …

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An Original Work: "Brothers And Sisters" And Songs From Letters By Libby Larsen : An Analysis, Andrea J. Mitternight Jan 2004

An Original Work: "Brothers And Sisters" And Songs From Letters By Libby Larsen : An Analysis, Andrea J. Mitternight

LSU Doctoral Dissertations

This dissertation consists of two parts. The first part is an original composition by the author entitled "Brothers and Sisters." The orchestra piece is an expressive program symphony in three movements. The first movement features sections of driving rhythms and fluctuating meters. Two new sections, more reflective and stable in nature, offset the more volatile sections. Herein lie moments of steady and unchanging rhythms and a sense of constancy. The movement ends with a return of the furious instability heard in the previous sections. Unlike the first movement, the second begins with a more somber mood. The introduction exposes the …

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Design And Operating Strategies For Bioreactors Treating Dynamically Varying Concentrations Of Gas-Phase Volatile Organic Compounds (Vocs), Congna Li Jan 2004

Design And Operating Strategies For Bioreactors Treating Dynamically Varying Concentrations Of Gas-Phase Volatile Organic Compounds (Vocs), Congna Li

LSU Doctoral Dissertations

The dynamically varying concentrations of volatile organic compounds (VOCs) in most waste gas streams present a challenge in design and operation of biofilters treating such off-gases. Studies described in this dissertation were directed toward development and experimental testing of two design modifications/operating strategies that have the potential to improve biofilter performance during unsteady-state loadings. In the first design modification studied, activated carbon was incorporated into biofilter packing media and a novel periodic operating strategy, Sequencing Batch Biofilter (SBB) operation, was tested under “normal” and various “shock” loading conditions treating methyl ethyl ketone contaminated air. Results demonstrate how the operational flexibility …

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Cost Effective And Sequential Methods For Teaching Educational Paraprofessionals To Implement Behavior Management Strategies In Preschool Classrooms, Natalie Jan Slider Jan 2004

Cost Effective And Sequential Methods For Teaching Educational Paraprofessionals To Implement Behavior Management Strategies In Preschool Classrooms, Natalie Jan Slider

LSU Doctoral Dissertations

This study examined the efficacy of cost effective and sequential training methods for teaching educational paraprofessionals to implement behavior management strategies in preschool classrooms. Investigation of the effects of increasingly complex and time consuming methods of training on both paraprofessional and student behaviors were evaluated. Training methods employed included written take-home manuals and summary cards, modeling videotapes, and performance feedback. Training materials included three behavior management strategies (e.g., instruction-giving, praise, and time out) that have shown to have extensive support in the empirical literature (Brophy, 1981; Budd, Riner, & Brockman, 1983; Flanagan, Adams, & Forehand, 1979; O’Dell, Krug, Patterson, & …

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International Ffa School To School Linkage Program: Case Studies Of Two Familes, Bradley Allen Leger Jan 2004

International Ffa School To School Linkage Program: Case Studies Of Two Familes, Bradley Allen Leger

LSU Doctoral Dissertations

The National FFA Organization is an agriculturally-based youth organization in the United States which has been providing/facilitating international experiences for its members for a number of years. One of these programs is the International FFA School to School Linkage Program (SSLP), in which selected American agricultural education/FFA programs are linked with specialized secondary agricultural schools/lyceums located in one of the countries of the former Soviet Union (FSU). The program’s main mission is for American students and teachers to share ideas with their FSU counterparts about the initiation and maintenance of small-scale agricultural entrepreneurships based on the United States’ agricultural education …

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The Effect Of Program Commitment On The Degree Of Participative Congruence And Managerial Performance In A Budgeting Setting, Kevin T. Breaux Jan 2004

The Effect Of Program Commitment On The Degree Of Participative Congruence And Managerial Performance In A Budgeting Setting, Kevin T. Breaux

LSU Doctoral Dissertations

The purpose of this research endeavor is to investigate the effect that the degree of participative congruence has on the relationship between program commitment and managerial performance. The degree of participative congruence (Clinton and Hunton 2001) is a new measure of participation designed to determine the amount of congruence between the perceived need for participation and the degree of participation allowed. This study used a questionnaire to evaluate the antecedents of and effects of the degree of participative congruence (DPC) in a budgeting setting. In order to investigate these effects, the questionnaire was mailed to a sample of 1,500 AICPA …

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Material Length Scales In Gradient-Dependent Plasticity/Damage And Size Effects: Theory And Computation, Rashid Kamel Abu Al-Rub Jan 2004

Material Length Scales In Gradient-Dependent Plasticity/Damage And Size Effects: Theory And Computation, Rashid Kamel Abu Al-Rub

LSU Doctoral Dissertations

Structural materials display a strong size-dependence when deformed non-uniformly into the inelastic range: smaller is stronger. This effect has important implications for an increasing number of applications in structural failure, electronics, functional coatings, composites, micro-electro-mechanical systems (MEMS), nanostructured materials, micro/nanometer fabrication technologies, etc. The mechanical behavior of these applications cannot be characterized by classical (local) continuum theories because they incorporate no ‘material length scales’ and consequently predict no size effects. On the other hand, it is still not possible to perform quantum and atomistic simulations on realistic time and structures. It is therefore necessary to develop a scale-dependent continuum theory …

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What Irritates Consumers?: An Empirical Examination Of The Antecedents And Consequences Of Consumer Irritation, Sweta Chaturvedi Thota Jan 2004

What Irritates Consumers?: An Empirical Examination Of The Antecedents And Consequences Of Consumer Irritation, Sweta Chaturvedi Thota

LSU Doctoral Dissertations

This dissertation develops a model of consumer irritation in the context of consumer decision-making. Thus, the purpose is to describe and empirically test a model of the antecedents and consequences of consumer irritation. The model incorporates antecedents, moderators and consequences of irritation. It is suggested that irritation in consumers has a direct as well as an indirect influence, through retention of irritation in consumers, on the outcome variables such as attitude towards the advertised brand, and intentions to engage in negative word of mouth (NWOM) behavior. The central aim of this dissertation is to extend our understanding of the irritation …

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Ctp: Phosphoethanolamine Cytidylytransferase And Dag: Cdp-Ethanolamine Ethanolaminephosphotransferase In The Cdp-Ethanolamine Pathway Of Chlamydomonas Reinhardtti, Wenyu Yang Jan 2004

Ctp: Phosphoethanolamine Cytidylytransferase And Dag: Cdp-Ethanolamine Ethanolaminephosphotransferase In The Cdp-Ethanolamine Pathway Of Chlamydomonas Reinhardtti, Wenyu Yang

LSU Doctoral Dissertations

Chlamydomonas reinhardtii Dangeard does not have two major phospholipids, PS and PC. This fact renders C. reinhardtii a desirable system for investigations of the PE biosynthetic pathway and its regulation independent of PC and PS biosynthesis. The cDNA coding for ECT protein in C. reinhardtii was cloned from a cDNA library. The ECT cDNA encodes a protein of 443 amino acid residues. The ECT protein in C. reinhardtii has a repetitive internal sequence in its N- and C-terminal halves. Each repeat half of the protein has a HXGH motif, a site considered to be in the catalytic domain. The protein …

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The Radon-Gauss Transform, Vochita Mihai Jan 2004

The Radon-Gauss Transform, Vochita Mihai

LSU Doctoral Dissertations

Gaussian measure is constructed for any given hyperplane in an infinite dimensional Hilbert space, and this is used to define a generalization of the Radon transform to the infinite dimensional setting, using Gauss measure instead of Lebesgue measure. An inversion formula is obtained and a support theorem proved.

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Effects Of Gp130 Cytokines On Adipocytes, Sanjin Zvonic Jan 2004

Effects Of Gp130 Cytokines On Adipocytes, Sanjin Zvonic

LSU Doctoral Dissertations

Members of the gp130 cytokine family are known for their pleiotropic roles in various cell types. Our work has focused on their actions in adipocytes. CNTF administration has been shown to ameliorate most complications associated with obesity and type 2 diabetes through an unknown mechanism. In this study CNTF is shown to activate JAK/STAT and MAPK signaling, both in vitro and in vivo. In 3T3-L1 adipocytes, chronic CNTF also regulates the expression of SREBP-1, FAS, IRS-1 and GLUT4. Acute CNTF administration enhances the activation of IRS-1 and Akt by insulin. Our data also demonstrate that the expression of CNTF-specific receptor, …

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Microelectrophoresis System Utilizing Conductivity Detection Analyzing Biological Molecues, Michelle Galloway Jan 2004

Microelectrophoresis System Utilizing Conductivity Detection Analyzing Biological Molecues, Michelle Galloway

LSU Doctoral Dissertations

Microfabrication technology has proven to be a valuable tool for creating polymer-based devices utilized in chemical and biochemical assays. Although, reducing the size of the device allows for short analysis times and reduces the reagent demand to ultrasmall volumes (< 1 nanoliter), a resulting consequence is the constraint placed on the limits of detection associated with the detector hardware required for readout. To overcome such constraints, laser-induced fluorescence (LIF) is often employed as a detection method as it provides low detection limits, which approach the single molecule level. Unfortunately, most LIF systems do not offer the benefits of miniaturization, with the detector components (i.e. laser, optics, filters) often times requiring a much larger footprint compared to the device. Another readout strategy that has shown promise for these devices is conductivity detection. Detection can be accomplished using either conventional-size or microfabricated electrodes, which can be integrated on the device. Although conductivity has been commonly used to detect inorganic or small organic species, the potential for detection of biological species has received little attention. In this work, an integrated conductivity detector was developed for the analysis of amino acids, peptides, proteins, and oligonucleotides (double-stranded DNA). Using the detector, mass detection sensitivities in the range of 10-18 - 10-21 moles were achieved. To increase the throughput of the system a state-of-the-art, multichannel device with a conductivity array detector was devised. This device, which consists of a 16-channel fluidic network and a printed circuit board, is geared toward automating three-processing steps onto a single fluidic platform including purification, preconcentration and detection for downstream parallel processing.

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