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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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Entry-Level Job Skills Needed By Wildlife Management Professionals, Billy Warren Delany, Jr. Jan 2004

Entry-Level Job Skills Needed By Wildlife Management Professionals, Billy Warren Delany, Jr.

LSU Doctoral Dissertations

The research purpose was to identify the job skills needed by entry-level wildlife managers, which was accomplished by utilizing a Delphi panel of wildlife management experts from the academic, private and public employment sectors. The Delphi panel was selected from a committee nominated, pool of 81 innovative wildlife management experts. The panel for Rounds One, Two, and Three of this Delphi survey consisted of 31, 32, and 31 members, respectively. The Delphi process involved three survey rounds. Round One consisted of collecting and developing entry-level job skill items from the panel, which resulted in 382 items. Round Two developed initial …

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Botany In Children's Literature: A Content Analysis Of Plant-Centered Children's Picture Books That Have A Plot And Characters, Sheila Lewis Goins Jan 2004

Botany In Children's Literature: A Content Analysis Of Plant-Centered Children's Picture Books That Have A Plot And Characters, Sheila Lewis Goins

LSU Doctoral Dissertations

This content analysis study examined 36 plant-centered children’s science picture books that have a plot and characters published from 1950 to present. Botanical subject matter and learning opportunities offered by these books were analyzed, along with the range and frequency of the National Science Education Standards-consistent and age-appropriate plant science concepts and principles. The science graphics, artistic innovations, and story plot of these books were also examined. Rubrics and research-based recommendations were developed to offer parents, teachers, and librarians assistance in identifying, evaluating, and using such books to help children of ages 4-8 learn about plants and enjoy plant science. …

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Somatic Cell Interspecies Nuclear Transfer, Marina Julia Sansinena Jan 2004

Somatic Cell Interspecies Nuclear Transfer, Marina Julia Sansinena

LSU Doctoral Dissertations

The low efficiency of the nuclear transfer (NT) procedure requires large number of oocytes to produce embryos and live offspring. A series of experiments were conducted to evaluate the ability of the bovine cytoplast to reprogram nuclei from horses and llamas. In a preliminary study, equine oocytes from small (<20mm diameter) follicles were either pretreated with roscovitine or placed in maturation (IVM only) prior to NT. Roscovitine pretreatment did not improve nuclear maturation rates (roscovitine pretreatment 57% vs. IVM only 66%) and no fusion was obtained from roscovitine-pretreated oocytes after NT. Another preliminary study was conducted with the objective to produce llama NT embryos and to compare their development in two in vitro culture conditions (G1.2® vs. CR1aa). No difference was found in the number of embryos cleaved after 2 d of culture. This resulted in the first scientific report of somatic cell NT, in vitro culture and transfer of NT embryos in the llama. In the next experiment, adult horse and llama fibroblasts were injected into enucleated cow oocytes. The results showed the cow cytoplasm is capable of partially reprogramming nuclei from other species and support mitotic divisions. However, this study also showed a consistent embryonic developmental arrest at the 8- to 16- cell stage when horse or llama donor cells were used as donor nuclei. When a more closely related species of donor cell (banteng) and recipient oocyte (domestic cattle) were used for NT, no embryonic developmental arrest was found. Embryos progressed to achieve high blastocyst rates (banteng male cell line 28% vs. banteng female cell line 15%). Two banteng interspecies NT pregnancies were established and subsequently lost from the banteng male cell line. In the final study, the effect of a mixed mitochondrial population (heteroplasmy) on early embryonic development was investigated. Ooplasmic transfer performed in combination with NT procedure indicated presence of foreign mitochondria clustered in a small portion of the cytoplasm in early stages of embryo development. When goat ooplasm was transferred into interspecies (cow oocyte-goat donor cell) NT embryos, fusion and cleave rates were reduced suggesting an increased level of heteroplasmy or nuclear-ooplasmic incompatibilities.

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Molecular Genetics And Functions Of Kaposi's Sarcoma-Associated Herpesvirus Glycoproteins In Viral Entry And Virus-Induced Cell Fusion, Rafael E. Luna Jan 2004

Molecular Genetics And Functions Of Kaposi's Sarcoma-Associated Herpesvirus Glycoproteins In Viral Entry And Virus-Induced Cell Fusion, Rafael E. Luna

LSU Doctoral Dissertations

Kaposi’s sarcoma-associated herpesvirus (KSHV) is considered the etiologic agent of Kaposi’s sarcoma and several lymphoproliferative disorders. Recently, the full-length KSHV genome has been cloned into a bacterial artificial chromosome (BAC) and successfully recovered in 293 cells. The herpesviral glycoproteins are structural components of the KSHV particle and are thought to facilitate virus entry, egress and virus-induced cell fusion. Investigations, described herein, have focused on the genetic manipulation of the KSHV-BAC36 in order to address the role of K8.1 glycoprotein in virus entry and the role of the carboxyl tail a-helices of glycoprotein (gB) in virus-induced cell fusion. In addition, a …

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Feeding Ecology And Morphometric Analysis Of Paddlefish, Polyodon Spathula, In The Mermentau River, Louisiana, Nicole Adele Smith Jan 2004

Feeding Ecology And Morphometric Analysis Of Paddlefish, Polyodon Spathula, In The Mermentau River, Louisiana, Nicole Adele Smith

LSU Master's Theses

Little is known about the morphometrics and the feeding ecology of paddlefish in Louisiana. I examined the morphometrics and feeding ecology of paddlefish from the Mermentau River, Louisiana from March 2002 to February 2003. Paddlefish were examined morphometrically by taking measurements of eye-fork length (EFL), body cavity length (BCL), girth (G), vent girth (VG), mouth vertical (MTB), mouth horizontal (MSS), and mouth gullet bottom (MGB) to determine which parameters would give a better estimate of weight (W). Regression analysis resulted in a morphometric model of the form: logW = 10.10 + 1.52 (logEFL) + 1.21 (logG) + 0.24 (logVG) (r2 …

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Evaluation Of Rough Brucella Strains As Vaccines For Brucellosis And Pseudorabies In Swine, Lorraine Harrow Molin Jan 2004

Evaluation Of Rough Brucella Strains As Vaccines For Brucellosis And Pseudorabies In Swine, Lorraine Harrow Molin

LSU Master's Theses

Brucellosis and pseudorabies lead to abortion in pregnant sows and are perpetuated by feral swine reservoirs. A multivalent oral vaccine for these diseases would improve vaccination and eradication programs worldwide. Previous studies have shown that the rough attenuated Brucella strains RB51 and VTRS1, when administered subcutaneously to swine, stimulate host immune responses, transiently colonize tissues, and provide partial protection against virulent B. suis infection in pregnant sows. A plasmid encoding for the pseudorabies virus glycoprotein D (PRV gD) has also been added to these strains as part of this project. This study evaluates the use of these strains as oral …

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The Effects Of Nutrient Enrichment On The Decomposition Of Belowground Organic Matter In A Sagittaria Lancifolia - Dominated Oligohaline Marsh, Kristen Raye Laursen Jan 2004

The Effects Of Nutrient Enrichment On The Decomposition Of Belowground Organic Matter In A Sagittaria Lancifolia - Dominated Oligohaline Marsh, Kristen Raye Laursen

LSU Master's Theses

Wetlands improve water quality through sedimentation and the uptake of excess nutrients. As human population increases in the coastal zone, wetlands receive greater nutrient inputs. These additional nutrients may accelerate microbial activity, leading to faster decomposition rates. This decomposition could exceed belowground organic matter production, resulting in a net reduction in soil organic matter accumulation and vertical marsh accretion. The effects of nutrient enrichment on belowground organic matter decomposition in subtropical marshes have received little attention. As such, this research examined the effects of four levels of nitrogen combined with two levels of phosphorus enrichment on belowground decomposition through the …

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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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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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Abiotic And Biotic Factors Affecting The Distribution Of Solenopsis Invicta Buren, Brachymyrmex Sp., And Linepithema Humile (Mayr) In East Baton Rouge Parish, Louisiana, Jessica Lynn Rosson Jan 2004

Abiotic And Biotic Factors Affecting The Distribution Of Solenopsis Invicta Buren, Brachymyrmex Sp., And Linepithema Humile (Mayr) In East Baton Rouge Parish, Louisiana, Jessica Lynn Rosson

LSU Master's Theses

Ant populations and their distribution are affected by many circumstances. Abiotic factors such as weather, water availability, and soil characteristics may determine if a habitat is suitable for ants. Other factors such as level of disturbance, available food resources, reproductive biology, and natural enemies also contribute to defining ant distribution. Three ant species in East Baton Rouge parish, Louisiana were studied to determine what factors affected their distribution by measuring abiotic and biotic factors at sampling sites throughout the parish. These factors included weather, water availability, vegetation types, level of disturbance, and soil characteristics. Factors which predict abundance of Solenopsis …

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Stormwater Diversion As A Potential Coastal Wetland Restoration Method, Jennifer Howard Woods Jan 2004

Stormwater Diversion As A Potential Coastal Wetland Restoration Method, Jennifer Howard Woods

LSU Master's Theses

The Barataria-Terrebonne estuary has been eroding at a rate of up to 103.6 km2 yr-1 for several decades. If the current rate of loss is not reduced, an additional 2,550 km2 of coastal wetlands will be lost by the year 2050. Currently, stormwater in Terrebonne Parish is pumped into canals, ultimately discharging into the Gulf of Mexico. An opportunity exists to use this stormwater for wetland restoration; however, the ecological impacts of stormwater diversions on wetlands are unknown. The objectives of this project were to 1) to investigate the seed banks of a degraded marsh to determine if a viable …

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Case Study Analysis Of Strategic Alliances For The U.S. Beef Industry, Angel Bu Zapatta Jan 2004

Case Study Analysis Of Strategic Alliances For The U.S. Beef Industry, Angel Bu Zapatta

LSU Master's Theses

This paper provides case studies on the structure of six strategic alliances in the beef industry. Strategic alliances are identified whose structure could conceivably be used in Louisiana. Strategic alliances are compared and contrasted on the basis of development and performance. The main objective of this study was to determine the organization and operation of six strategic alliances in the beef industry. The study examines strategic alliances in the U.S. beef industry using multiple exploratory case studies. The exploratory type, allows the researcher to better understand critical points in the beef industry and how the use of strategic alliances can …

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Physicochemical And Functional Properties Of Crawfish Chitosan As Affected By Different Processing Protocols, Sun-Ok Fernandez-Kim Jan 2004

Physicochemical And Functional Properties Of Crawfish Chitosan As Affected By Different Processing Protocols, Sun-Ok Fernandez-Kim

LSU Master's Theses

Chitosan is made from chitin by a chemical process involving demineralization (DM), deproteinization (DP), decolorization (DC), and deacetylation (DA). Very little work has been done to demonstrate the effects of altering or excluding any of the processing steps on chitosan characteristics. The present study was undertaken to evaluate the effects of process modification during chitosan production on the physiochemical and functional properties of crawfish chitosans. Five experimental chitosan samples (DCMPA, DMCPA, DMPCA, DMPAC, DAMPC) prepared with modified processing protocols and the control (DPMCA - traditional chitosan production process) were evaluated and compared with the two commercial crab chitosans. All samples …

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Investigation Of Insect-Weed Interactions In The Rice Agroecosystem, Kelly V. Tindall Jan 2004

Investigation Of Insect-Weed Interactions In The Rice Agroecosystem, Kelly V. Tindall

LSU Doctoral Dissertations

Interactions between graminaceous weed and insect pests of rice and between management practices for these pests were investigated. Studies were conducted to examine preference and performance of rice water weevil, Lissorhoptrus oryzophilus Kuschel, on several weeds commonly found in rice fields. Several weeds were more preferred than rice, and larvae were present on several dicotyledonous weeds, suggesting the host range of L. oryzophilus is broader than previously thought. Effects of the presence of barnyardgrass, (Echinochloa crus-galli Beauv.), on rice stink bugs, Oebalus pugnax F., and L. oryzophilus populations in rice fields were investigated. Presence of barnyardgrass and the synchrony …

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Integration Of Management Tactics For The Rice Water Weevil Lissorhoptrus Oryzophilus Kuschel With Particular Emphasis On Use Of Plant Resistance (Tolerance), Li Zou Jan 2004

Integration Of Management Tactics For The Rice Water Weevil Lissorhoptrus Oryzophilus Kuschel With Particular Emphasis On Use Of Plant Resistance (Tolerance), Li Zou

LSU Doctoral Dissertations

Studies were conducted to test the hypothesis, significant benefits can be achieved for the management of rice water weevil, Lissorhoptrus oryzophilus Kuschel, by the use of rice varieties with low levels of host plant resistance coupled with the judicious use of cultural practices and insecticides. Tolerant traits of a current commercial variety of rice, "Bengal", was manifested consistently over multiple years. Study on rice growth as effected by weevil injury showed that pruning of root systems by larvae of weevil resulted in a decrease in tiller number and shoot biomass of rice plants in the vegetative stage of growth. Yield …

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Isolation And Characterization Of Carbonic Anhydrase From Ostertagia Ostertagi, Andrew Allan Derosa Jan 2004

Isolation And Characterization Of Carbonic Anhydrase From Ostertagia Ostertagi, Andrew Allan Derosa

LSU Doctoral Dissertations

The first event in the infection process of Ostertagia ostertagi in cattle is the process of exsheathment. Before trichostrongylid nematodes can transition from a free-living infective stage larva (L3) on pasture to a parasitic existence within the ruminant host, it must first undergo exsheathment. Exsheathment is the process whereby the L2 cuticle retained from the previous molt is cast from the L3. Exsheathment enables the developmental transition from a free-living stage on pasture to a parasitic existence in the bovine host. For those species with a predilection site in the abomasum, such as O. ostertagi, …

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Thermodynamic Characterization Of Dna Binding By Type I Dna Polymerases From Thermus Aquaticus And Escherichia Coli, Kausiki Datta Jan 2004

Thermodynamic Characterization Of Dna Binding By Type I Dna Polymerases From Thermus Aquaticus And Escherichia Coli, Kausiki Datta

LSU Doctoral Dissertations

DNA binding of the DNA polymerase I from Thermus aquaticus (Taq and Klentaq fragment) and E. coli (Klenow fragment) have been studied as a function of [salt] and temperature in order to understand their DNA binding thermodynamics. Binding of the two different species of polymerases occurs with sub-micromolar affinities in very different salt concentration ranges. Thus, at similar [KCl] the binding of Klenow is ~ 3kcal/mol (150X) tighter than the binding of Taq/Klentaq. Linkage analysis of the [KCl] dependence of DNA binding at 25°C reveals a net release of 2-3 ions for Taq/Klentaq and 4-5 ions for Klenow. DNA binding …

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Profiles Of Early Childhood Education Administrators: Looking For Patterns Of Leadership, Mary Aileen Sciaraffa Jan 2004

Profiles Of Early Childhood Education Administrators: Looking For Patterns Of Leadership, Mary Aileen Sciaraffa

LSU Doctoral Dissertations

The purpose of this study was to conduct a systematic inquiry into the lives of six early childhood administrators. The researcher investigated stories these early childhood administrators told about their lived experiences and searched for patterns that emerged from the stories suggesting career paths, personal characteristics, and administrative styles. The sample was obtained from a purposive/criterion sampling of the population. Six early childhood administrators were chosen based on their representation as a strong administrator who had experience with working with young children and families. Data was collected through three interview sessions. The minimum time for each interview session was one …

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The Effects Of Auditory Distraction On Attention Performance In Asymptomatic College Students With A History Of Mild Head Injury, John H.,Ii Denning Jan 2004

The Effects Of Auditory Distraction On Attention Performance In Asymptomatic College Students With A History Of Mild Head Injury, John H.,Ii Denning

LSU Doctoral Dissertations

Introduction: The majority of individuals experiencing a mild head injury (MHI) recover fully experiencing few residual symptoms. Some individuals who fully recover have shown evidence of residual, albeit subtle, brain functioning disturbances on tasks requiring high levels of cognitive effort. Also, memory complaints in MHI patients may be related to these subtle difficulties when cognitive resources are overwhelmed. This study assessed a group of asymptomatic college students with a history of MHI to determine if there were any residual attention difficulties as well as increased memory complaints. Method: One-hundred twelve college students with and without a history of MHI were …

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Assessing The Identity Of Black Indians In Louisiana: A Quantitative And Qualitative Analysis, Francis J. Powell Jan 2004

Assessing The Identity Of Black Indians In Louisiana: A Quantitative And Qualitative Analysis, Francis J. Powell

LSU Doctoral Dissertations

This study shows the existence of Black Indians in Louisiana and investigates whether differences exist between Black Indians who are members of officially recognized tribes and those who do not have any type of recognition. The study examined if a relationship exist between tribal recognition and ethnic identity, subjective well-being, and social support. A cross-sectional survey design was used. Semi-structured interviews were conducted to obtain qualitative data. The sample consisted of 60 participants. 30 were from recognized tribal groups and 30 were from non-recognized tribal communities. The study specifically examined variables related to the perceptions of Black Indians in Louisiana …

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Protein Aggregation Studies: Inhibiting And Encouraging Β-Amyloid Aggregation, Jed Paul Aucoin Jan 2004

Protein Aggregation Studies: Inhibiting And Encouraging Β-Amyloid Aggregation, Jed Paul Aucoin

LSU Doctoral Dissertations

This work demonstrates peptide-based aggregation mediation of fibril forming peptides, notably β-amyloid (1-40), Aβ1-40. To achieve the goals of this work, Aβ1-40 aggregation was governed by ionic strength, temperature, and pH. After controlling and reproducing Aβ1-40 aggregate formation (fibrils), each peptide-based aggregation mediator was evaluated for its ability to self-aggregate and to possess surface-active properties. The incorporation of these mediators in Aβ1-40 solutions changed the surface tension and produced aggregate complexes of mediator and Aβ1-40. Evidence that Aβ1-40 fibril formation may be mediated by disorder-to-order transitions has been observed by layer formation …

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Spatial Analyses And Growth Of Trees In Selected Bottomland Hardwood Stands, Luben D. Dimov Jan 2004

Spatial Analyses And Growth Of Trees In Selected Bottomland Hardwood Stands, Luben D. Dimov

LSU Doctoral Dissertations

Sustainable management and conservation of the extensive bottomland hardwood forest resource in the southeastern U.S. requires a good understanding of basic structural and competitive relationships within these forests. To gain an insight into these relationships, plot information from stands in Arkansas, Louisiana, and Mississippi were analyzed. The effects of individual tree attributes, distance-dependant, and distance-independent competition measures on 5-yr radial growth of red oak crop trees were examined. Selected species included cherrybark oak (Quercus pagoda Raf.), water oak (Q. nigra L.), and Nuttall oak (Q. nuttallii Palmer). Spatial continuity of tree variables was explored through geostatistical analysis. Finally, spatial distribution …

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Analysis Of Bacterial Diversity And Biogeography At The Central Arizona-Phoenix Long Term Ecological Research (Cap Lter) Site, Brian Anthony Rash Jan 2004

Analysis Of Bacterial Diversity And Biogeography At The Central Arizona-Phoenix Long Term Ecological Research (Cap Lter) Site, Brian Anthony Rash

LSU Doctoral Dissertations

The limiting factor involved in past assessments of soil bacterial diversity when using culture-independent techniques has often been the lack of sampling and replication. As a result, analyses of community structural shifts across soil environments have lacked statistical power. In this study, 23 16S rRNA gene clone libraries consisting of over 11,000 clones were constructed from soils at the Central Arizona Phoenix Long Term Ecological Research (CAP LTER) site. Subsequent ARDRA fingerprinting and partial 16S rRNA gene sequencing allowed for a more robust investigation of various components that may explain any observed variations in bacterial species composition. The designated land …

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Attachment Of Oligonucleotide Probes To Polymer Biochips And Its Application For The Detection Of Point Mutations, Yun Wang Jan 2004

Attachment Of Oligonucleotide Probes To Polymer Biochips And Its Application For The Detection Of Point Mutations, Yun Wang

LSU Doctoral Dissertations

This dissertation is on the fabrication of polymer-based microfluidic arrays for the detection of genetic mutations. Poly(methyl methacrylate) was chosen as one of the polymer substrate materials due to its low background noise, low adsorption of biomolecules, and low assembly temperature. The surface modification of polymer substrates for covalent attachment of oligonucleotide probes, the construction of fluidic channels/arrays, and hybridization kinetics will be covered. As an example of the application, point mutation detection using immobilized arrays constructed in microfluidic devices will be demonstrated. The PMMA surface was derivatized with N-lithioethylenediamine solution to introduce amine groups, which were utilized for the …

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Analytical Separations Using Packed And Open-Tubular Capillary Electrochromatography, Constantina P. Kapnissi Jan 2004

Analytical Separations Using Packed And Open-Tubular Capillary Electrochromatography, Constantina P. Kapnissi

LSU Doctoral Dissertations

The goal of the research reported in this dissertation is to develop packed and open-tubular capillary electrochromatographic methods for improved achiral and chiral separations of various classes of analytes. The first part of this research involves the separation of seven benzodiazepines by the use of the packed mode of capillary electrochromatography (CEC) and a 40 cm packed bed of Reliasil 3 μm C18 stationary phase. Optimal conditions were established by varying the mobile phase, the amount of organic modifier, the buffer concentration, the applied voltage, and the column temperature. The second part of this research focuses on the open-tubular …

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Geography, Coloration And Speciation In A Genus Of Neotropical Reef Fishes (Gobiidae: Elacatinus), Michael S. Taylor Jan 2004

Geography, Coloration And Speciation In A Genus Of Neotropical Reef Fishes (Gobiidae: Elacatinus), Michael S. Taylor

LSU Doctoral Dissertations

Studies of speciation in the marine environment have historically compared broad-scale distributions and presumed larval dispersal to infer the geographic barriers responsible for allopatric speciation. However, many marine clades show high species diversity in geographically restricted areas where barriers are not obvious and larval dispersal should bring sister taxa into contact. Genetic differentiation at spatial scales <1000 km could facilitate speciation by mechanisms other than the gradual accumulation of reproductive isolation during extended allopatry, such as ecological adaptation to local environmental conditions or the rapid evolution of genes tied to mate recognition. The role of each of these possibilities has not been simultaneously explored for any species-rich marine taxon. The most species-rich genus of Neotropical reef fishes is Elacatinus (Gobiidae), with 27 species. I examine potential mechanisms underlying this richness through analyses of three genetic markers to investigate genetic and ecological differentiation between closely related taxa and among island populations. Phylogenetic analyses indicate that sister taxa of Elacatinus occur within the same oceans but occupy geographically separate ranges. Sister taxa usually differ by coloration, and distantly related sympatric species frequently differ by habitat. These differences suggest that some combination of coloration and ecological differences may facilitate assortative mating in sympatry or at range boundaries. The ranges of several Elacatinus taxa adjoin at Mona Passage and in the central Bahamas, both in the Caribbean Sea. These boundaries separate island populations by as few as 23 km, yet these populations are genetically distinct. Populations not separated by these breaks also show strong genetic structuring. Coalescent analyses suggest these populations have been demographically closed for up to 800,000 years. Such strong genetic structuring suggests that pelagic larvae are retained at natal populations, despite a three week larval duration (determined from otolith growth rings). My results suggest that local retention of pelagic larvae, coupled with biogeographic breaks, has generated or maintained strong genetic population structure which may facilitate adaptation to local ecological conditions. Such adaptations may explain observed divergence along ecological and coloration gradients. Repeated radiations among allopatrically distributed sister taxa may explain much of the high diversity in Elacatinus.

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Behavior Analysis In Child Welfare: A Preliminary Program Evaluation, Carole Marie Van Camp Jan 2004

Behavior Analysis In Child Welfare: A Preliminary Program Evaluation, Carole Marie Van Camp

LSU Doctoral Dissertations

The Behavior Analysis Services Program provides behavioral services, in the form of parenting classes and individualized assessments and treatments, to children and caregivers receiving child welfare services throughout the state of Florida. The program has many goals, including decreasing placement disruptions and increasing parenting skills. This study was a preliminary evaluation of the program that is now in its fourth year. First, characteristics of both foster children and foster parents that were associated with differential levels of placement disruptions were identified. Results identified several characteristics (i.e., being of a certain age, or having been in care for a certain amount …

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Modeling The Effects Of Rainfall Intensity And Deep Chiseling On Infiltration And Runoff Within Drainmod For Alluvial Soils, Daniel Nyabiba Moriasi Jan 2004

Modeling The Effects Of Rainfall Intensity And Deep Chiseling On Infiltration And Runoff Within Drainmod For Alluvial Soils, Daniel Nyabiba Moriasi

LSU Doctoral Dissertations

Accurate hydrologic models are needed to aid engineers and researchers design, install and evaluate efficient and cost-effective agricultural water management systems to reduce risks associated with food production, and to reduce soil erosion and water pollution. One model used for the alluvial soils of Louisiana is DRAINMOD. This model does not accurately predict infiltration and runoff for the crusting-prone alluvial soils of Louisiana. The main goal of this study was to modify the current DRAINMOD model to incorporate the effects of rainfall intensity and deep chiseling to improve its estimation of infiltration and surface runoff. The second goal was to …

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Students' Construction Of The Body In Physical Education, Laura Azzarito Jan 2004

Students' Construction Of The Body In Physical Education, Laura Azzarito

LSU Doctoral Dissertations

Recently, physical education researchers have been concerned about the results of national studies reporting young people's low level of participation in physical activity and health problems associated with inactivity. In general girls are less active than boys, and youth from low socioeconomic classes are less active and are more likely be unhealthy than middle or upper class youth. Blacks have the highest risks of health problems and the highest levels of physical inactivity. Among a number of recommendations included in Healthy People 2010, physical education has been identified as a fundamental site for addressing today's challenges. According to physical education …

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