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Book Embeddings Of Graphs, Robin Leigh Blankenship Jan 2003

Book Embeddings Of Graphs, Robin Leigh Blankenship

LSU Doctoral Dissertations

We use a structural theorem of Robertson and Seymour to show that for every minor-closed class of graphs, other than the class of all graphs, there is a number k such that every member of the class can be embedded in a book with k pages. Book embeddings of graphs with relation to surfaces, vertex extensions, clique-sums and r-rings are combined into a single book embedding of a graph in the minor-closed class. The effects of subdividing a complete graph and a complete bipartite graph with respect to book thickness are studied. We prove that if n ≥ 3, …

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Reticent Romans: Silence And Writing In La Vie De Saint Alexis, Le Conte Du Graal, And Le Roman De Silence, Evan J. Bibbee Jan 2003

Reticent Romans: Silence And Writing In La Vie De Saint Alexis, Le Conte Du Graal, And Le Roman De Silence, Evan J. Bibbee

LSU Doctoral Dissertations

Apart from discourse and yet somehow part of it, silence is a powerfully ambiguous linguistic phenomenon that blurs the lines between presence and absence. Eluding the material aspects of oral and written language, it is only perceptible as the gaps or spaces between words. Nonetheless, it plays a role in all linguistic productions: although silence itself cannot be directly communicated, it can influence communication. In a literary text, silence may takes on many different guises, including rhythmic hesitations, rhetorical omissions, and poetic oppositions that mimic the audible gaps of spoken language. The visual, aural, and fictional interaction of all these …

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Perceptions Of Stereotypes In Hispanic Children's Literature, Nancy Gomez Jan 2003

Perceptions Of Stereotypes In Hispanic Children's Literature, Nancy Gomez

LSU Doctoral Dissertations

This study attempted to determine the accurateness of the representation of the Hispanic culture in children’s books. I interviewed ten people: five non-Hispanic and five Hispanic, and I found that the Hispanic people do not seem to pay as much attention to physical features as non-Hispanic people do. However, they were concerned about the portrayal of the Hispanic culture in traditional ways: the traditional roles of women, the traditional dress, the architecture of the houses and the portrayal of the Hispanic people living in rural areas and being extremely poor. It appears that from the timeline covered by the books, …

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Control Of Transport Dynamics In Overlay Networks, Qishi Wu Jan 2003

Control Of Transport Dynamics In Overlay Networks, Qishi Wu

LSU Doctoral Dissertations

Transport control is an important factor in the performance of Internet protocols, particularly in the next generation network applications involving computational steering, interactive visualization, instrument control, and transfer of large data sets. The widely deployed Transport Control Protocol is inadequate for these tasks due to its performance drawbacks. The purpose of this dissertation is to conduct a rigorous analytical study on the design and performance of transport protocols, and systematically develop a new class of protocols to overcome the limitations of current methods. Various sources of randomness exist in network performance measurements due to the stochastic nature of network traffic. …

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A Study And An Approach To Historical Performance Practices In The French Baroque Based On François Couperin's Treiziéme Concert À 2 Instrumens À L'Unisson, James Jeffery Womack Jan 2003

A Study And An Approach To Historical Performance Practices In The French Baroque Based On François Couperin's Treiziéme Concert À 2 Instrumens À L'Unisson, James Jeffery Womack

LSU Doctoral Dissertations

The purpose of this document is to examine and explain historical performance practices as applicable to the Treiziéme Concert à 2 instrumens à L’unisson of Fran çois Couperin. It provides an in depth look at the written and unwritten traditions of tempo, articulation, phrasing, ornamentation, and the use of in égal. Meant as a guide for players of the modern bassoon, this monograph guides the reader through the aspects of performance practice listed above and their application to that instrument. This document contains an introductory chapter and a biographical chapter. The remaining chapters explain the components of historical performance practice …

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Gender Inequality, Concentrated Disadvantage, And Homicide Victimization: A Sex And Race Specific Analysis Of Homicide Victimization Rates In Large U.S. Cities, Ginger Donise Stevenson Jan 2003

Gender Inequality, Concentrated Disadvantage, And Homicide Victimization: A Sex And Race Specific Analysis Of Homicide Victimization Rates In Large U.S. Cities, Ginger Donise Stevenson

LSU Doctoral Dissertations

This dissertation is designed to extend prior research on the structural correlates of homicide victimization among demographic subgroups in large U.S. cities. The present study draws on two broad theoretical traditions - the concentrated disadvantage perspective and gender inequality perspectives. Using Supplementary Homicide Reports data for 1990, race- and sex-specific homicide victimization measures were constructed for 120 U.S. cities. Due to the extremely rare prevalence of homicide victimization among some demographic subgroups, Poisson and Negative Binomial Regression techniques are used to test a series of hypotheses regarding the effects of concentrated disadvantage and gender inequality on homicide victimization for four …

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De La Page D'Écriture Et Du Mythe De L'Ancêtre Rebelle: La Problématique De L'Écrite Et De La Parole Dans Le Roman Francophone Ouest Africain, Boubakary Diakite Jan 2003

De La Page D'Écriture Et Du Mythe De L'Ancêtre Rebelle: La Problématique De L'Écrite Et De La Parole Dans Le Roman Francophone Ouest Africain, Boubakary Diakite

LSU Doctoral Dissertations

The aim of this dissertation is to question the concept of orality as the natural expression of ancestors in African novels and press for a reading of West African writers, which values their fictional creation as autonomous from their cultural origins. The main purpose of this study is to examine, through series of close textual readings, how francophone West African novels distance themselves from oral tradition by fully assuming literacy as a characteristic of the post-colonial Africa. The first chapter attempts a redefinition of orality, as only a critical discourse aimed at translating the complexity and the suspected hybridity of …

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A Quantitative And Qualitative Evaluation Of The National Endowment For Democracy, Eric T. Hale Jan 2003

A Quantitative And Qualitative Evaluation Of The National Endowment For Democracy, Eric T. Hale

LSU Doctoral Dissertations

Billions of dollars have been spent to promote democracy and economic freedom through U.S. foreign aid, but little is known about its impact. The National Endowment for Democracy (NED) is the leading U.S. organization that promotes democracy and economic freedom throughout the world. Since its founding, NED has been the subject of immense discussion and controversy. The goal of this dissertation is to provide insight into the promotion of democracy and economic freedom through an analysis of NED’s activities during the 1990s. The analysis does not find evidence that NED was successful at promoting democracy and economic freedom during the …

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Deficit Politics And Democratic Unity: The Saga Of Tip O'Neill, Jim Wright, And The Conservative Democrats In The House Of Representatives During The Reagand Era, Karl Gerard Brandt Jan 2003

Deficit Politics And Democratic Unity: The Saga Of Tip O'Neill, Jim Wright, And The Conservative Democrats In The House Of Representatives During The Reagand Era, Karl Gerard Brandt

LSU Doctoral Dissertations

The Reagan Era featured partisan clashes, controversy over fiscal policy, and a time of trial for the Democratic Party and its claim of diversity. This dissertation examines the efforts of the House Democratic Leadership to build party unity and to enhance its operating methods in battles with the Reagan administration over fiscal policy and the future of the United States. The House Democratic Leadership was challenged by the conservative Democrats. In 1980, the conservatives formed the Conservative Democratic Forum (CDF). Acting as a quasi-third party, the CDF was instrumental in passage of Reagan's economic program in 1981. Afterwards, the CDF …

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Cultural Competence Of Faculty Of Baccalaureate Nursing Programs, Lorinda J. Sealey Jan 2003

Cultural Competence Of Faculty Of Baccalaureate Nursing Programs, Lorinda J. Sealey

LSU Doctoral Dissertations

The purpose of this study was to examine the level of cultural competence among faculty teaching in baccalaureate nursing programs in Louisiana and to identify associated factors. A survey was mailed to all 313 faculty members identified as actively involved in teaching in any baccalaureate nursing program in Louisiana and 163 valid responses were obtained. The Cultural Diversity Questionnaire for Nurse Educators, a researcher designed instrument intended to measure cultural competence, was the instrument used. It included Likert-type items organized into five subscales representing the components of cultural competence according to Campinha- Bacote’s model of cultural competence (i.e., cultural awareness, …

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Immunological, Hematological, And Serum Biochemical Effects Of High Level Dietary Fish Oil And Vitamin E Supplementation In The Dog, Casey J. Leblanc Jan 2003

Immunological, Hematological, And Serum Biochemical Effects Of High Level Dietary Fish Oil And Vitamin E Supplementation In The Dog, Casey J. Leblanc

LSU Doctoral Dissertations

Inflammation is a component of the innate immune response. However, severe or prolonged inflammation can be detrimental. Dietary n-3 fatty acid supplementation has proven clinical benefits in chronic inflammatory diseases, most likely due to reduced synthesis of inflammatory mediators and inhibition of lymphocyte proliferation and function. The purposes of this study were to characterize alterations in inflammatory mediator production, and lymphocyte proliferation, in dogs fed a diet consisting of 0.65% n-3 fatty acids (DMB) with an n-6:n-3 fatty acid ratio of 3.4:1. Fifteen dogs were randomly assigned to one of three dietary groups for twelve weeks. Group Sunflower oil received …

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Bioavailability And Bioaccumulation Of Sediment-Associated, Desorption-Resistant Fraction Of Polycyclic Aromatic Hydrocarbon Contaminants, Xiaoxia Lu Jan 2003

Bioavailability And Bioaccumulation Of Sediment-Associated, Desorption-Resistant Fraction Of Polycyclic Aromatic Hydrocarbon Contaminants, Xiaoxia Lu

LSU Doctoral Dissertations

This study is directed toward identifying and characterizing the bioavailability of both reversibly sorbed and desorption-resistant fraction of hydrophobic organic contaminants in natural biologically active sediments and the corresponding consequences to prediction, control and regulation of these contaminants. The focus is on polycyclic aromatic hydrocarbons (PAHs) with particular emphasis on phenanthrene and benzo[a]pyrene. A quantity of well-characterized and extensively desorbed sediments was prepared by desorbing the lab-inoculated sediment with an isopropanol and electrolyte solution. This procedure was proved to be a very effective method to prepare sediments containing contaminants largely limited to a desorption-resistant compartment. Accumulation of contaminants in the …

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Two Essays On Corporate Hedging: The Choice Of Instruments And Methods, Pinghsun Huang Jan 2003

Two Essays On Corporate Hedging: The Choice Of Instruments And Methods, Pinghsun Huang

LSU Doctoral Dissertations

This dissertation examines corporate use of derivative instruments and multi-period hedging methods. It studies the use of linear (e.g. futures) and nonlinear (e.g. options) derivatives in a sample of 382 U.S. non-financial firms (920 firm-year observations) between 1992 and 1996. It also measures the performance of stacked hedge techniques with applications to three investment assets (heating oil, light crude oil, and unleaded gasoline) and to three commercial commodities (British Pound, Deutsche Mark, and Swiss Franc). In a stacked hedge, corporations hedge the long-term exposures by repeatedly rolling nearby futures contracts until settlement. Analyzing the 382 firms, I find that both …

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The Relationship Between Depression And Feeding Disorder Symptoms Among Persons With Severe And Profound Mental Retardation, Stephen Bradley Mayville Jan 2003

The Relationship Between Depression And Feeding Disorder Symptoms Among Persons With Severe And Profound Mental Retardation, Stephen Bradley Mayville

LSU Doctoral Dissertations

In recent years, feeding disorders have been described in detail, and various assessment and treatment methods for these disorders have been reported. Within the literature, an emphasis has been placed on functional variables responsible for the onset and maintenance of feeding disorders, yet little has been reported on the relationship between feeding disorders and other forms of psychopathology. Therefore, the relationship between depression and feeding disorders was assessed. Three groups of individuals were compared across subscales and individual items on the Screening Tool for Feeding Problems (STEP) to assess for differences in problematic feeding behavior. Individuals who met diagnostic criteria …

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Biology And Ecology Of Leptographium Species And Their Vectos As Components Of Loblolly Pine Decline, Lori G. Eckhardt Jan 2003

Biology And Ecology Of Leptographium Species And Their Vectos As Components Of Loblolly Pine Decline, Lori G. Eckhardt

LSU Doctoral Dissertations

Loblolly pine (Pinus taeda L.) decline (LPD) has been present in upland sites of central Alabama since the 1960s. Symptoms of LPD (fine root deterioration, short chlorotic needles, sparse crowns, reduced radial growth) begin in the 30-40 yr age class, resulting in premature death at ages 35-50. Previously, declining loblolly was diagnosed as littleleaf disease (LLD); however, site conditions associated with LPD are different from LLD sites. Littleleaf disease only occurs on eroded, heavy clay soils and is secondarily associated with the fungus, Phytophthora cinnamomi. In contrast, LPD occurs on sandy, well-drained soils and is associated with Leptographium spp., as …

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Enhanced Pectin Degradation Is Associated With The Ease Of Fruit Detachment In Tabasco Pepper, Ramon Alejandro Arancibia Jan 2003

Enhanced Pectin Degradation Is Associated With The Ease Of Fruit Detachment In Tabasco Pepper, Ramon Alejandro Arancibia

LSU Doctoral Dissertations

Pectin metabolism was analyzed in tabasco pepper (Capsicum frutescens L.) to determine the metabolic process associated with the ease of fruit detachment from the calyx. Two genotypes that differ in the fruit detachment force (FDF) were used: 'Easy Pick' (EZ) which requires a low force and 'Hard Pick' (HP) which requires higher force. Pectin dissolution in fresh ripe fruit tissue and in extracted fruit cell wall was higher in the EZ genotype than the HP genotype and inversely correlated to the FDF. Size-exclusion chromatography of EDTA-soluble polyuronides indicated that pectin was degraded in ripe tissue from both genotypes, but the …

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Arm Crank Power And Hyperammonemia In Respones To L-Aspartic Acid Supplementation, William W. Edwards Jan 2003

Arm Crank Power And Hyperammonemia In Respones To L-Aspartic Acid Supplementation, William W. Edwards

LSU Doctoral Dissertations

PURPOSE: To examine the effect of L-Aspartic Acid (L-Asp) supplementation on short-term arm-crank power (i.e. W·min-1) and exercise-induced hyperammonemia in two gender-specific investigations. METHODS: The male investigation (MALE) used nine highly-trained intercollegiate water polo players (WP) and nine moderately-trained college students (MOD); the female investigation (FEM) used 18 recreationally-trained college students. All exercised to exhaustion on two occasions following counterbalanced double-blind ingestion of 12.5g x 2 of L-Asp or placebo (P). The warm-up phase began at 25 W·min-1 and increased in 25 W·min-1 stages every 30 seconds (constant 100 rpm). Performance began (i.e. the subjects turned …

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Cross-Cultural Construct Validation Of The Learning Transfer System Inventory In Tawian, Hsin-Chih Chen Jan 2003

Cross-Cultural Construct Validation Of The Learning Transfer System Inventory In Tawian, Hsin-Chih Chen

LSU Doctoral Dissertations

Human Resource Development has historically made a large contribution to Taiwan's economic growth. Organizations in Taiwan perceive training as one of their top priorities to maintain their competitive advantage. Although many organizations have spent considerable money on training, there has been a lack of a comprehensive, generalizable, psychometrically-sound instrument to investigate transfer of learning in Taiwan. This study cross-culturally validated the constructs of the Learning Transfer System Inventory (LTSI) for use in Taiwan. By doing so, HRD practitioners in Taiwan can benefit by having an instrument to diagnose intervening variables and improve individual performance. The LTSI was translated through a …

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The Solo Style Of Jazz Clarinetist Johnny Dodds: 1923 - 1938, Patricia A. Martin Jan 2003

The Solo Style Of Jazz Clarinetist Johnny Dodds: 1923 - 1938, Patricia A. Martin

LSU Doctoral Dissertations

The purpose of this study is to explore the personality, background, influence and playing style of Johnny Dodds (1892-1940), a New Orleans jazz clarinetist. Jazz is an art form that has been passed down aurally for over a hundred years. Although the development of jazz and the performers who played it have been the subject for numerous jazz historians, there are still scant resources available for a musician to learn jazz clarinet style. The ease with which a musician can emulate an early jazz clarinetist depends on the amount of time devoted to listening and emulating whatever recordings are available. …

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Effects Of Submergence And Hypoxia On The Growth And Anatomy Of Rice (Oryza Sativa L.) Seedlings, Denise M. D'Abundo Jan 2003

Effects Of Submergence And Hypoxia On The Growth And Anatomy Of Rice (Oryza Sativa L.) Seedlings, Denise M. D'Abundo

LSU Doctoral Dissertations

Aerenchyma - a specialized tissue with abundant, interconnected gas spaces - facilitates oxygen transport from shoots to roots in many emergent wetland plants. The importance of oxygen transport to root elongation and aerenchyma development in rice (Oryza sativa L.) seedlings was demonstrated in this investigation. Germinated seeds of Lemont (a commercial cultivar) and red rice (an agricultural weed) were positioned at 4.5, 2.5, or 1.0 cm below the surface of aerated or hypoxic water to control the duration of leaf submergence and the availability of oxygen. Primary root and leaf lengths were measured daily. Aerenchyma was compared among emergent and …

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Mediators Of Weight Loss In An Internet-Based Intervention For African American Adolescent Girls, Marney A. White Jan 2003

Mediators Of Weight Loss In An Internet-Based Intervention For African American Adolescent Girls, Marney A. White

LSU Doctoral Dissertations

The primary aim of this study was to assess the process variables involved in a weight loss program for African-American adolescent girls. This internet-based intervention compared a behavioral treatment program to an educational treatment program; it was hypothesized that participants randomized to the behavioral condition would lose more weight at 6 months than those in the educational condition. Several process variables have been identified as affecting success in in vivo weight loss programs for adults and children, including program adherence, self-efficacy, and social support. The current study sought to broaden the understanding of these process variables as they pertain to …

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Treatment Of Chlorinated Volatile Organic Compounds Using Wetland Systems, Gabriel Roderick Kassenga Jan 2003

Treatment Of Chlorinated Volatile Organic Compounds Using Wetland Systems, Gabriel Roderick Kassenga

LSU Doctoral Dissertations

Bench-scale continuous vertical flow column and microcosm studies were conducted to investigate the attenuation potential of chlorinated volatile organic compounds (CVOCs) in constructed wetland soil mixtures prepared from peat, compost and sand and in a pristine natural freshwater wetland soil. The study also determined geotechnical properties of potential synthetic peat mixtures for construction of treatment wetlands for CVOCs. Trichloroethene (TCE), cis-1,2-dichloroethene (cis-1,2-DCE) and 1,2-dichloroethane (1,2-DCA) were the main test chemicals used during the studies. Based on geotechnical and sorption characteristics, two mixtures (one comprised of sand and peat and the other comprised of sand, peat and compost product) were selected …

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High Carbon Dioxide Requiring Mutants Of Chlamydomonas Reinhardtti, Steve Vincent Pollock Jan 2003

High Carbon Dioxide Requiring Mutants Of Chlamydomonas Reinhardtti, Steve Vincent Pollock

LSU Doctoral Dissertations

Chlamydomonas reinhardtii is a photosynthetic alga that has the ability to concentrate CO2 around Rubisco to achieve enhanced rates of photosynthesis in a low CO2 environment. This dissertation presents results obtained from the generation and analysis of four high CO2 requiring mutants of C. reinhardtii. The use of reverse genetics is a very powerful tool to dissect out the individual components of metabolic pathways. Two reverse genetics methods were utilized in this study: a random insertional mutagenesis method to discover genes that are required for growth in a low CO2 environment, and a directed mutagenesis approach, RNA interference, to determine …

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Solute Transport In A Porous Medium: A Mass-Conserving Solution For The Convection-Dispersion Equation In A Finite Domain, William Golz Jan 2003

Solute Transport In A Porous Medium: A Mass-Conserving Solution For The Convection-Dispersion Equation In A Finite Domain, William Golz

LSU Doctoral Dissertations

This dissertation considers the proper mathematical description for the physical problem of a miscible solute undergoing longitudinal convective-dispersive transport with constant production, first-order decay, and equilibrium sorption in a porous medium. Initial and input concentrations may be any continuously differentiable functions and the mathematical system is articulated for a finite domain. This domain yields a mass balance which requires Robin (i.e., third-type) boundaries, which describe a continuous flux but a discontinuous resident-concentration. The discontinuity in the resident concentration at the outflow boundary yields an underdetermined system when the exit concentration is not experimentally measured. This is resolved by defining the …

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Fractal Compression And Analysis On Remotely Sensed Imagery, Ke Xiao Jan 2003

Fractal Compression And Analysis On Remotely Sensed Imagery, Ke Xiao

LSU Doctoral Dissertations

Remote sensing images contain huge amount of geographical information and reflect the complexity of geographical features and spatial structures. As the means of observing and describing geographical phenomena, the rapid development of remote sensing has provided an enormous amount of geographical information. The massive information is very useful in a variety of applications but the sheer bulk of this information has increased beyond what can be analyzed and used efficiently and effectively. This uneven increase in the technologies of gathering and analyzing information has created difficulties in its storage, transfer, and processing. Fractal geometry provides a means of describing and …

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Agronomic And Molecular Characterization Of Louisiana Native Spartina Alterniflora Accessions, Alicia Beatriz Ryan Jan 2003

Agronomic And Molecular Characterization Of Louisiana Native Spartina Alterniflora Accessions, Alicia Beatriz Ryan

LSU Doctoral Dissertations

Coastal erosion and wetland deterioration are serious and widespread problems affecting Louisiana’s coastal zone. The application of agronomic and molecular techniques for improving crop species is well documented. However, these have not been routinely applied to species of ecological and environmental value. Spartina alterniflora is used extensively for shoreline protection and tidal marsh restoration because of its aggressive spreading habit and tolerance to salinity. The progress of marsh revegetation projects is limited by the costs and labor associated with vegetative propagation of Spartina. Hence, a breeding program was initiated to develop improved smooth cordgrass accessions with superior seed producing ability …

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The Contribution Of The Alpha Subunit Of The Bacillus Subtilis Rna Polymerase In The Enhancement Of Transcription By Curved Dna, Caroline Telles Jan 2003

The Contribution Of The Alpha Subunit Of The Bacillus Subtilis Rna Polymerase In The Enhancement Of Transcription By Curved Dna, Caroline Telles

LSU Doctoral Dissertations

Adenine-tract mediated, intrinsic DNA curvature is found upstream of highly transcribed promoters in bacteria. In Bacillus subtilis, curved DNA immediately upstream of the core promoter stimulates promoter function. The curved DNA functions in a position-sensitive fashion indicating that it likely interacts with the RNA polymerase. There are two components of the curved DNA that mediate this interaction with RNA polymerase, the A+T rich nature of the runs of adenines spaced with the helical repeat of the DNA and the curved shape of the DNA. The alpha subunit of the RNA polymerase from Escherichia coli is known to bind to A+T …

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The Epidemiology Of Shiga-Toxigenic Escherichia Coli O157:H7 In Louisiana Cattle, And White-Tailed Deer, John Robert Dunn Jan 2003

The Epidemiology Of Shiga-Toxigenic Escherichia Coli O157:H7 In Louisiana Cattle, And White-Tailed Deer, John Robert Dunn

LSU Doctoral Dissertations

Shiga-toxigenic Escherichia coli (STEC) O157:H7 is an important human pathogen. Dairy cattle, beef cattle, and white-tailed deer (WTD) are involved in STEC O157:H7 transmission to humans. We conducted cross-sectional studies in Louisiana, using sensitive microbiological methods, in dairy cattle, beef cattle, and WTD to investigate the epidemiology of STEC O157:H7. Results of the dairy studies are as follows. In the point prevalence study, summer-time prevalence in herds was 38.5%, with a cow-level prevalence of 6.5%. Among positive herds, cow-level prevalence ranged from 3%-34.6%. Three of five herds sampled in the longitudinal study were positive. Cow-level prevalence increased during spring and …

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Evolution Of Ecological Diversity In The Neotropical Tanagers Of The Genus Tangara (Aves: Thraupidae), Kazuya Naoki Jan 2003

Evolution Of Ecological Diversity In The Neotropical Tanagers Of The Genus Tangara (Aves: Thraupidae), Kazuya Naoki

LSU Doctoral Dissertations

The origin and maintenance of biological diversity has been one of the fundamental issues in biology. However, the evolution of ecological traits that affect species coexistence and species diversity is poorly known. My research aimed to investigate the evolution of species-specific ecological and morphological traits and to understand the process of ecological diversification and species coexistence in Tangara tanagers (Thraupidae) by using phylogenetic comparative methods. Tangara is the largest avian genus in the New World with 50 recognized species. As many as ten species of Tangara are found sympatrically in the same Andean cloud forest, and many syntopic species travel …

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The Invasive Tropical Shrub Clidemia Hirta (Melastomataceae) In Its Native And Introduced Ranges: Tests Of Hypotheses Of Invasion, Saara Jennie Dewalt Jan 2003

The Invasive Tropical Shrub Clidemia Hirta (Melastomataceae) In Its Native And Introduced Ranges: Tests Of Hypotheses Of Invasion, Saara Jennie Dewalt

LSU Doctoral Dissertations

Exotic pest plants often grow to greater stature, become more abundant, and display increased shade tolerance in their introduced ranges than in their native ranges. These differences have been hypothesized to result from genetic shifts in biomass allocation, growth, or photosynthesis between genotypes in native and introduced ranges or from plastic, phenotypic responses to different environmental conditions, such as lower herbivore or fungal pest loads in areas of introduction. I used the tropical shrub Clidemia hirta (Melastomataceae) as a model exotic pest plant to test these two non-mutually exclusive hypotheses of invasion. Clidemia hirta invades forest understory and is more …

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