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Influence Of Tumor Necrosis Factor-Alpha And Minocycline On Microglia And Macrophage Activation During Polytropic Retrovirus Infection, Meryll E. Corbin Jan 2007

Influence Of Tumor Necrosis Factor-Alpha And Minocycline On Microglia And Macrophage Activation During Polytropic Retrovirus Infection, Meryll E. Corbin

LSU Master's Theses

Microglia/macrophage activation has been associated with the pathogenesis of various neurological diseases including human immunodeficiency virus encephalitis, transmissible spongiform encephalitis, and Alzheimer's disease (AD). In vitro studies have indicated a role for TNFα in activating these cells which leads to their migration, proliferation, and secretion of proinflammatory cytokines and chemokines that may potentially damage brain tissue. In the current study, we analyzed the phenotype of microglia and macrophages enriched from wild type and TNFα deficient mice infected with a neurovirulent murine retrovirus. Although TNF receptors CD120a and CD120b were expressed on both microglia and macrophage population, unaltered by either retrovirus …

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Effect Of Red Imported Fire Ant (Solenopsis Invicta Buren) On The Nesting Success Of Northern Bobwhite (Colinus Virginianus L.), Michael Andrew Seymour Jan 2007

Effect Of Red Imported Fire Ant (Solenopsis Invicta Buren) On The Nesting Success Of Northern Bobwhite (Colinus Virginianus L.), Michael Andrew Seymour

LSU Master's Theses

The Northern Bobwhite (Colinus virginianus L.) has experienced average yearly decline of 3% in the United States from 1966-2005. Factors implicated in decline include habitat destruction, alteration of farm practices, and red imported fire ant (RIFA) (Solenopsis invicta Buren). Effect of RIFA on bobwhites has been a hot topic leading to formation of polarized camps – those who believe RIFA have little effect and those who believe the effect will further threaten the species’ survival. The main objective of this study was to determine if RIFA affect nesting of bobwhites and at what stage in nesting birds are most vulnerable. …

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Forest Fragmentation Effects On Seed Dispersal, Seed Fate, And Fruit Production Of Duckeodendron Cestroides And Bocageopsis Multiflora In The Brazilian Amazon, Jennifer Mei Cramer Jan 2007

Forest Fragmentation Effects On Seed Dispersal, Seed Fate, And Fruit Production Of Duckeodendron Cestroides And Bocageopsis Multiflora In The Brazilian Amazon, Jennifer Mei Cramer

LSU Doctoral Dissertations

In tropical forests, forest fragmentation that alters species interactions between plants and animals, especially mutualisms, will affect the regeneration of trees. Fragmentation reduced Duckeodendron cestroides seed dispersal quantity and quality. The percent and distance of dispersed seeds were twice as great in continuous forest (31%, 4.9 m) as in fragments (15%, 2.5 m). Differences were even more exaggerated for each tree's furthest dispersed seeds. Distributions of dispersed seeds across distance showed more seeds at all distances in continuous forest than in fragments. Dispersal differences were strongest in years when fruit production was high and resulted in a greater number of …

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Spatial Analysis Of The Preserved Wooden Architectural Remains Of Eight Late Classic Maya Salt Works In Punta Ycacos Lagoon, Toledo District, Belize, Bretton Michael Somers Jan 2007

Spatial Analysis Of The Preserved Wooden Architectural Remains Of Eight Late Classic Maya Salt Works In Punta Ycacos Lagoon, Toledo District, Belize, Bretton Michael Somers

LSU Doctoral Dissertations

This dissertation examined the remains of wooden architecture at eight Late Classic Maya sites found beneath the surface of Punta Ycacos Lagoon in southern Belize. The presence of briquetage on the surface and embedded among the clusters of wooden architectural features implies association with salt production activity. This research is significant in that the preservation of wooden structures at the salt works has not previously been reported for the ancient Maya. This dissertation includes a detailed discussion of documented evidence of salt production throughout Mesoamerica from archaeological, historical and modern examples. The discussion also addressed the evidence of Maya wooden …

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An Evaluation Of An Inshore Aquaculture Park For Sustainable Coastal Community Development, Vanesssa Maxwell Jan 2007

An Evaluation Of An Inshore Aquaculture Park For Sustainable Coastal Community Development, Vanesssa Maxwell

LSU Doctoral Dissertations

This dissertation addresses applying industrial park concepts to the development of aquaculture parks in public waters specifically for off-bottom triploid Easter oyster, Crassostrea virginica, culture. The objectives are to identify the permitting process, relevant agencies, and legislation needed to facilitate development of aquaculture parks in the Gulf of Mexico states, and test and analyze off-bottom oyster culture for commercial production of triploid oysters. Off-bottom culture can increase oyster production, but fouling organisms can reduce growth and survival rates. The Adjustable Longline System (ALS), commercially used in Australia, allows oyster bags to be suspended in the water column and positioned for …

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Evaluation Of Selected Immune Response To Haemonchus Contortus In Gulf Coast Native Compared To Suffolk Lambs, Krishna P. Shakya Jan 2007

Evaluation Of Selected Immune Response To Haemonchus Contortus In Gulf Coast Native Compared To Suffolk Lambs, Krishna P. Shakya

LSU Doctoral Dissertations

Haemonchus contortus is one of the major nematode parasites causing substantial economic losses in small ruminant farming worldwide. Recently, effect of anthelmintic treatment has decreased due to an increasing problem of nematode populations that have developed resistance to anthelmintics. There are certain breeds of sheep that are identified as being relatively resistant to the parasite including Gulf Coast Native (Native) sheep. Understanding the mode of immune response that helps these breeds of sheep control infection could help design vaccines and enhance control programs. This experiment was designed to evaluate the immunological responses of Native, compared with susceptible Suffolk sheep that …

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Sugarcane Tasseling Under Artificial Photoperiod Conditions As Affected By Nitrogen Rate And Temperature, Christopher Michael Laborde Jan 2007

Sugarcane Tasseling Under Artificial Photoperiod Conditions As Affected By Nitrogen Rate And Temperature, Christopher Michael Laborde

LSU Doctoral Dissertations

Optimizing flowering in the LSU AgCenter’s Sugarcane ( Sacchrum spp. hybrids) Breeding Program is an important step in the variety development program. The effect of nitrogen and ambient air temperature in pot cultured sugarcane were examined as a means of improving sugarcane flowering. The experiment was conducted on agronomic and reproductive traits of sugarcane at the Sugar Research Station, St. Gabriel, LA, on sugarcane genotypes subjected to artificial photoperiod regimes. The potting media consisted of equal parts of washed sand, Canadian peat moss, and a Commerce silt loam soil (fine-silty, mixed, nonacid, thermic aeric Fluvaquents). Early nitrogen (22.4-22.4-22.4 kg ha-1) …

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The Influence Of Enrollment In Agriscience Education Courses On Student Achievement Of High School Students In Louisiana, Paul Joseph Theriot Jan 2007

The Influence Of Enrollment In Agriscience Education Courses On Student Achievement Of High School Students In Louisiana, Paul Joseph Theriot

LSU Doctoral Dissertations

The purpose of this study was to compare academic achievement of high school students in Louisiana by whether or not they are identified as an agriscience education student. The rationale for the study is to determine if agriscience education contributes to the academic achievement of high school students. The Louisiana Educational Assessment Program (LEAP) Graduate Exit Exams were used to measure academic achievement. All graduate exit exam test scores for the 2004-2005 school year were utilized for the study. The data for this study came from the Louisiana Department of Education. The study described all 10th and 11th grade students …

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Synaptic Boojums: Lewis Carroll, Linguistic Nonsense, And Cyberpunk, Jennifer Kelso Farrell Jan 2007

Synaptic Boojums: Lewis Carroll, Linguistic Nonsense, And Cyberpunk, Jennifer Kelso Farrell

LSU Doctoral Dissertations

Tracing a line from Lewis Carroll to 20th-century science fiction and cyberpunk, this project establishes an alternate genealogy based on the use of linguistic nonsense. Science fiction, rather than being merely a genre defined by specific narrative devices or character traits, is instead a language in and of itself. And like any language, it must be learned in order to be understood. Carroll used nonsense as a means of subverting conventional 19th-century opinions of language and, and by extension, society. Carroll was so successful at this that in 1937 American psychiatrist Paul Schilder discussed the dangers to a child's mind …

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Lymphohistiocytic Proliferative Syndrome Of Alligators (Alligator Mississippiensis): A Cutaneous Manifestation Of West Nile Virus, Javier G. Nevarez Jan 2007

Lymphohistiocytic Proliferative Syndrome Of Alligators (Alligator Mississippiensis): A Cutaneous Manifestation Of West Nile Virus, Javier G. Nevarez

LSU Doctoral Dissertations

ABSTRACT In 1999, there were reports of a new type of lesion in the hides of captive reared alligators from Florida. Similar lesions were first reported from alligator hides in Louisiana in 2001; however, it wasn’t until 2002 that small epizootics became apparent. In 2002, the Louisiana Department of Wildlife and Fisheries began a collaborative effort with the Louisiana State University School of Veterinary Medicine (LSU SVM) to help elucidate the etiology of “PIX” disease, later renamed Lymphohistiocytic Proliferative Syndrome of Alligators (LPSA). Preliminary work concluded that LPSA was a systemic disease affecting multiple tissues. Based on the results of …

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Effect Of Age, Body Condition, Pregnancy And Lactation On Circulating Leptin Concentrations In Beef Cattle, Glen Talmage Gentry, Jr. Jan 2007

Effect Of Age, Body Condition, Pregnancy And Lactation On Circulating Leptin Concentrations In Beef Cattle, Glen Talmage Gentry, Jr.

LSU Doctoral Dissertations

A series of experiments were conducted to evaluate the potential role of leptin in bovine reproduction. In Experiment 1, mean circulating leptin concentrations of postpartum cows were not affected by exogenous dexamethasone treatments. In Experiment 2, mean leptin concentrations were not correlated with female age or body weight but were positively correlated with body condition scores of beef cattle. Leptin concentrations were higher in 1 year old heifers (8.9 ng/ml) compared with 2 year old cows (6.0 ng/ml), but heifer leptin concentrations were not different than 4 to 6 year old cows (8.0 ng/ml) and cows ≥7 years of age …

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Dna-Binding And Oligomerization Properties Of A Functionally Distinct Dps Homolog, Dps-1 From Deinococcus Radiodurans, Gargi Bhattacharyya Jan 2007

Dna-Binding And Oligomerization Properties Of A Functionally Distinct Dps Homolog, Dps-1 From Deinococcus Radiodurans, Gargi Bhattacharyya

LSU Doctoral Dissertations

Dps (DNA protection during starvation) proteins play an important role in the protection of prokaryotic macromolecules from damage by reactive oxygen species. The Dps homolog, Dps-1, from the radiation-resistant bacterium Deinococcus radiodurans has an extended N-terminal tail. In the crystal structure of Dps-1, the first ~30 N-terminal residues are invisible and the remaining 25 residues form a loop that harbors a novel metal binding site. The data presented here show that retention of this N-terminal metal site is necessary for formation of the dodecameric protein assembly. Previous studies have suggested that the lysine-rich N-terminus of Dps proteins participates in DNA …

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Workplace Implications For Hurricane Affected Gulf Coast Region Industrial Companies, Michelle T. Boullion Jan 2007

Workplace Implications For Hurricane Affected Gulf Coast Region Industrial Companies, Michelle T. Boullion

LSU Doctoral Dissertations

Organizational perspectives on the effects of disasters on employee behavior in the workplace and the related adjustments organizations make as a result of disaster are examined in this study. The survey instrument utilizes constructs of what organizations have done for their employees in regards to personal and family needs, business earnings and efforts to maintain continued business operations, philanthropy and volunteer activities, hiring and employee retention, safety and security, employee performance and activity, physical, mental or emotional effects, and human resource department adjustments or areas of coping as a result of Hurricane's Katrina and Rita. Rebuilding timeframes for physically damaged …

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Detection Of West Nile Virus Activity In Male And Female Mosquitoes, And Evaluation Of Host-Utilization Patterns Of Mosquitoes, In East Baton Rouge Parish, Louisiana, Andrew James Mackay Jan 2007

Detection Of West Nile Virus Activity In Male And Female Mosquitoes, And Evaluation Of Host-Utilization Patterns Of Mosquitoes, In East Baton Rouge Parish, Louisiana, Andrew James Mackay

LSU Doctoral Dissertations

ABSTRACT Host utilization patterns of female mosquitoes, and WNV infection rates in male and female mosquitoes, were examined in East Baton Rouge Parish to identify potential vectors of West Nile virus (WNV). A total of 244,374 female mosquitoes were collected between November 2002 and October 2004 and tested by viral isolation. Additionally, 131,896 female mosquitoes were tested by VecTest in 2003, and 167,175 female mosquitoes were tested by RT-PCR in 2004. West Nile virus was isolated from 17 of 36 mosquito species assayed by virus isolation, WNV antigens were detected in 9 of 27 species tested by VecTest, and WNV …

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Role Of Heparanase And Heparanase-Degraded Heparan Sulfate In Brain-Metastatic Melanoma, Madhuchhanda Roy Jan 2007

Role Of Heparanase And Heparanase-Degraded Heparan Sulfate In Brain-Metastatic Melanoma, Madhuchhanda Roy

LSU Doctoral Dissertations

Cancer metastasis is a frequent manifestation of malignant melanoma progression. Successful invasion into distant organs by tumor cells must include attachment to microvessel endothelial cells, and degradation of extracellular matrix. Heparan sulfate proteoglycans are ubiquitous macromolecules associated with cell surface and extracellular matrix of a wide range of cells and tissues. Heparanase is an extracellular matrix degradative enzyme which degrades the heparan sulfate chains of heparan sulfate proteoglycans. To investigate effects of changes in heparanase gene expression in metastatic melanoma cells, we constructed adenoviral vectors containing the full-length human heparanase cDNA in both sense (Ad-S/hep) and anti-sense orientations (Ad-AS/hep). We …

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Alphabetic And Phonemic Awareness In Toddlers, Pamela A. Terrell Jan 2007

Alphabetic And Phonemic Awareness In Toddlers, Pamela A. Terrell

LSU Doctoral Dissertations

The ability of 20-24 month-old toddlers to recognize graphemes and phonemes was investigated by reading a Phonic Faces (PF) alphabet picture book. Phonic Faces iconically picture a letter in the mouth of a character producing the sound (the curve of the P looks like the top lip popping the /p/ sound). The book was composed of nine letters and was read individually to experimental subjects three times weekly for six weeks. The control group received no treatment, but engaged in individual play activities for comparable time. Following six-weeks the groups alternated so the former control group now received the alphabet …

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Using Group Dynamics And Personality Characteristics To Form Learning Groups In High School Multimedia Courses, Kimberly Nichols Laprairie Jan 2007

Using Group Dynamics And Personality Characteristics To Form Learning Groups In High School Multimedia Courses, Kimberly Nichols Laprairie

LSU Doctoral Dissertations

The purpose of this study was to provide insights into Emergenetics® STEPTM personality profiling as a selection and placement strategy to enhance process and performance in high school learning groups. An explanatory case study was conducted in a private high school currently subscribing to the Emergenetics® STEPTM program. Emergenetics® STEPTM Profile results of students enrolled in the school’s six Multimedia Productions courses were analyzed as the basis for learning group construction. Key individual thinking preferences (Analytical, Structural, Social, Conceptual) identified by the STEPTM Profile was the main variable of analysis. One learning group from each of the six classes (n …

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Brucella Melitensis: The Evaluation Of A Putative Hemagglutinin Gene's Effect On Virulence In The Caprine Model, Quinesha Laticia Perry Jan 2007

Brucella Melitensis: The Evaluation Of A Putative Hemagglutinin Gene's Effect On Virulence In The Caprine Model, Quinesha Laticia Perry

LSU Doctoral Dissertations

Brucella melitensis is a facultative intracellular bacterial pathogen that causes abortions in goats and sheep and Malta fever in humans. The zoonotic disease brucellosis causes severe economic losses in the Mediterranean region and parts of Africa, Asia, and Latin America. With the completion of the genomic sequences of B. abortus 2308 and B. melitensis 16M, no classical virulence factors were found; and the chromosomes were virtually identical. However, in B. melitensis, a putative hemagglutinin gene was identified which is absent in B. abortus. The possibility of the hemagglutinin gene being a potential virulence factor was evaluated via gene replacement/deletion in …

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Assessment Of Thelypteris Palustris, Asparagus Sprengeri, And Lolium Perenne For Their Potential Use In The Phytoremediation Of Arsenic-Contaminated Soils, Lashunda L. Anderson Jan 2007

Assessment Of Thelypteris Palustris, Asparagus Sprengeri, And Lolium Perenne For Their Potential Use In The Phytoremediation Of Arsenic-Contaminated Soils, Lashunda L. Anderson

LSU Doctoral Dissertations

The goal of this study is to evaluate the potential of three plants, Thelypteris palustris (marsh fern), Asparagus sprengeri (asparagus fern), and Lolium perenne (perennial ryegrass) for use in phytoremediation of arsenic-contaminated soils. Specifically, the objectives of this study are to (1) confirm if arsenic accumulation occurs in the selected plants, (2) to examine morphological effects of arsenic in the selected plants, and (3) to evaluate the oxidation state of arsenic upon accumulation in the selected plants. The analytical method combination of ICP-MS, SEM, and XANES was used to accomplish the objectives of this study. The results indicate marsh fern, …

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Experimental And Modeling Studies Of Contaminant Transport In Capped Sediments During Gas Bubble Ebullition, Qingzhong Yuan Jan 2007

Experimental And Modeling Studies Of Contaminant Transport In Capped Sediments During Gas Bubble Ebullition, Qingzhong Yuan

LSU Doctoral Dissertations

Fluxes of the three organics and eighteen metals from sediments were measured with diffusion chambers, and the effectiveness of a sand cap ascertained. The influence of sediment consolidation on contaminant flux and the mass transfer coefficient at the sediment-water interface was studied. A two-layer diffusion-advection model and consolidation model were coupled to elucidate the effect of sediment consolidation on chemical transport in the sediment-cap system. The model was tested and verified by the experimental data from microcosms, and then was used to predict phenanthrene flux under field conditions. The simulation results showed that consolidation could accelerate phenanthrene breakthrough and enhance …

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Chagas In Culture And Place: A Mixed Methods Approach To A New Medical Geography Of Chagas Disease In Los Tuxtlas, Mexico, Frances Heyward Currin Mujica Jan 2007

Chagas In Culture And Place: A Mixed Methods Approach To A New Medical Geography Of Chagas Disease In Los Tuxtlas, Mexico, Frances Heyward Currin Mujica

LSU Doctoral Dissertations

This project is concerned with a new medical geography approach to investigating Chagas disease in Los Tuxtlas, Mexico which focuses on the intersection of disease risk and place. More specifically this work will describe the domestic cycle of Chagas disease and the cultural factors that perpetuate its transmission in six communities in the Los Tuxtlas region, Municipio San Andres, Veracruz State, Mexico. Using several collection techniques, such as interviews and house type surveys, as well as identifying and collecting the vector Triatoma dimidiata (including testing them for the parasite Trypanosoma cruzi), this dissertation describes the characteristics of the Chagas landscape …

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Synthesis Of Quaternary Dendronized Cellulose Derivatives And Their Potential Biological Applications, Changde Zhang Jan 2007

Synthesis Of Quaternary Dendronized Cellulose Derivatives And Their Potential Biological Applications, Changde Zhang

LSU Doctoral Dissertations

In this dissertation, novel dendronized cellulose derivatives with biodegradable backbones were created by using sodium carboxymethyl cellulose (CMC) as the starting material. CMC was first transformed into its corresponding tetrabutyl ammonium salt, which reacted with 2-chloro-N-methylpyridinium iodide (CMPI) to produce an activated ester of [2-(N-methyl pyridium) carboxymethyl cellulose] iodide (MPCMCI). The reaction of MPCMCPI and di-tert-butyl 4-[2-(ter-butoxycarbonyl)ethyl]-4-aminoheptanedicarboxylate (BA) produced a new derivative with BA dendron elaborated on cellulose backbone (CMCBA). The degree of substitution (DS) of CMCBA was adjusted by controlling the relative concentration of CMPI and by choosing CMC with different DS or different molecular weights. Thermogrametric analysis (TGA) …

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Spatial Econometric Analysis Of Agglomeration Economies Associated With The Geographical Distribution Of The U.S. Biotech Industry, Pramod Reddy Sambidi Jan 2007

Spatial Econometric Analysis Of Agglomeration Economies Associated With The Geographical Distribution Of The U.S. Biotech Industry, Pramod Reddy Sambidi

LSU Doctoral Dissertations

This dissertation analyzed spatial agglomeration economies associated with the geographical distribution of the U.S. biotech industry. Three location issues associated with the biotech industry were addressed in the study. The first study utilized a Bayesian spatial tobit model and examined the overall and regional differences in factors affecting the location of the U.S. biotech industry. The second study examined the inter- and intra-industry spatial association of biotech related research and development (R&D) and testing facilities across all contiguous U.S. counties employing a Spatial Two-Stage Least Squares model. Finally, the interdependence between different subsectors of the U.S. biotech industry was analyzed …

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Chromosomal Stability And Epigenetic Modifications Of Fibroblast Cells Used For Nuclear Transfer, Angelica Maria Giraldo Gomez Jan 2007

Chromosomal Stability And Epigenetic Modifications Of Fibroblast Cells Used For Nuclear Transfer, Angelica Maria Giraldo Gomez

LSU Doctoral Dissertations

Investigations into the importance of the nuclear integrity of the donor cell prior to nuclear transfer (NT) are limited. In Experiment 1, the proliferative characteristics, chromosomal stability and level of histone phosphorylation in cell lines established by explants and enzymatic dissociation at different population doublings (PDs) were investigated. The cells divided at a constant rate and cell cycle length increased only at the end of the proliferative stage. The level of aneuploidies was high and remained elevated throughout the study independent of the technique used to establish the primary culture. High levels of multinucleated cells and abnormal spindle configurations were …

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Visualizing The Menstrual Cycle: Effects Of A Redesigned Cycle Diagram On Community College Biology Students' Learning, Francesca Maria Mellieon-Williams Jan 2007

Visualizing The Menstrual Cycle: Effects Of A Redesigned Cycle Diagram On Community College Biology Students' Learning, Francesca Maria Mellieon-Williams

LSU Doctoral Dissertations

This mixed methods, exploratory study investigated the importance of the menstrual cycle diagram for understanding human reproduction. Several theories were used to support this study including Visual Design Theory (Tufte, 1990, 1997, 2001), and Human Constructivist Theory (Mintzes, Wandersee, Novak 1998). The two sexuality education programs used by society, abstinence-only programs and comprehensive sex education programs were compared to illustrate how this study applies to the current state of sexuality education in the United States. Community college students from two institutions in the southern region of the United States, registered in five introductory biological science courses, participated in a unit …

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Understanding The New York Rabies Epizootic 1985-2005, David Dorrell Jan 2007

Understanding The New York Rabies Epizootic 1985-2005, David Dorrell

LSU Doctoral Dissertations

Surveillance data are an important part of medical geography. These data are used to produce much of the analyses that define the subdiscipline. It is understood that surveillance data may contain biases, but there have only been limited studies devoted to determining in what ways the data are not representative of actual disease prevalence. New York was selected for this research for several reasons. First, it has a strong rabies data set. Second, it has a centralized system of licensing animal and dog control officers. Third, it is well-represented in terms of local media. This dissertation attempts to better understand …

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The Relative Impact Of Nicotine Dependence Versus Other Substance Dependence On Decision-Making, Michael S. Businelle Jan 2007

The Relative Impact Of Nicotine Dependence Versus Other Substance Dependence On Decision-Making, Michael S. Businelle

LSU Doctoral Dissertations

Research has indicated that individuals who are dependent on substances may have decision-making deficits that contribute to their continued substance use. Previous studies have shown that substance-dependent individuals focus more on the immediate rather than the delayed consequences of their actions, and more rapidly discount rewards that are available after a delay than individuals without a history of substance dependence. The present study compared the performance of four groups of individuals on the Gambling Task and the Delayed Discounting Task. The groups were (a) heavy smokers with comorbid substance dependence, (b) heavy smokers with no history of substance dependence, (c) …

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Copper(Ii) Oxide Mediated Formation And Stabilization Of Combustion Generated Persistent Free Radicals, Hieu Truong Jan 2007

Copper(Ii) Oxide Mediated Formation And Stabilization Of Combustion Generated Persistent Free Radicals, Hieu Truong

LSU Doctoral Dissertations

Biologically damaging semiquinone-type radicals have been reported in cigarette smoke, their likely origin being hydroquinone (HQ) and catechol (CT) molecular precursors contained by the tobacco. Since other biomass contains HQ and CT-type species, it is likely that combustion of other biomass will also form semiquinone-type radicals. All hydrocarbon fuels will form phenol and substituted phenol that can form substituted phenoxyl radicals. Because each of these radicals has the potential to be environmentally persistent and biologically active, their formation and stabilization from various molecular precursors was studied with the focus on surface-bound radicals formed in association with combustion-generated fly-ash particles. Comprehensive …

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Effects Of Cryopreservation And Constituents Of Semen Extenders On Mitochondrial Function Of Bull Spermatozoa, Abdulhakeem Hashim Eljarah Jan 2007

Effects Of Cryopreservation And Constituents Of Semen Extenders On Mitochondrial Function Of Bull Spermatozoa, Abdulhakeem Hashim Eljarah

LSU Doctoral Dissertations

This study investigated the effects of semen extender constituents and cryopreservation on bovine spermatozoal mitochondrial function. Three yearling Holstein bulls were used. Two ejaculates per bull were collected and pooled on a weekly basis for five weeks and extended in four treatments: 1) sodium citrate egg yolk extender with antibiotics (lincomycin, spectinomycin, gentamicin and tylosin); 2) ¡°1¡± with glycerol; 3) ¡°2¡± without antibiotics; and 4) ¡°1¡± without antibiotics. Each was divided into portions for analyses before freezing and after cryopreservation. The pre-freeze and thawed semen were transferred to a 37¡ãC water bath, the same assays were performed. In experiment 1, …

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Floral Traits, Pollinator Behavior, And Plant Reproduction: Tests Of Natural And Sexual Selection In The Hummingbird-Pollinated Herb Chrysothemis Friedrichsthaliana, Jane Elizabeth Carlson Jan 2007

Floral Traits, Pollinator Behavior, And Plant Reproduction: Tests Of Natural And Sexual Selection In The Hummingbird-Pollinated Herb Chrysothemis Friedrichsthaliana, Jane Elizabeth Carlson

LSU Doctoral Dissertations

Pollinators may promote floral evolution by selectively visiting preferred floral phenotypes. Herbivores may also influence the evolution of floral traits, by reducing the fitness of poorly-defended plants, such as those without protective sepals. In this dissertation, I investigate the reproductive and evolutionary consequences of floral visitors for two floral traits of the Neotropical herb Chrysothemis friedrichsthaliana (Gesneriaceae). I focus on the trait male-biased nectar production, which results from coincident temporal shifts in nectar production rates and sexual function within flowers. First, I review theory relevant to male- and female-biased nectar production, and I generate hypotheses to explain its evolution in …

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