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Structural Characterization Of Beta Carbonic Anhydrases From Higher Plants., Michael H. Bracey Jan 1998

Structural Characterization Of Beta Carbonic Anhydrases From Higher Plants., Michael H. Bracey

LSU Historical Dissertations and Theses

It is the goal of this dissertation research to reveal some aspects of the physical nature of spinach carbonic anhydrase as a representative $\beta$CA using the techniques of sequence comparison, molecular biology, and biophysics. Though both $\alpha$ and $\beta$ carbonic anhydrases are zinc dependent metalloenzymes, it is clear that the two isoforms do not adopt the same mechanism for coordinating the active site metal. While $\alpha$CA binds zinc through three histidine ligands, $\beta$CA cannot due to a lack of evolutionarily conserved histidines. Instead, the $\beta$ family has adopted a ligand scheme incorporating a single histidine and two cysteines. This has …

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Supplemental Organic Chromium For Dairy Calves., Christopher L. Depew Jan 1998

Supplemental Organic Chromium For Dairy Calves., Christopher L. Depew

LSU Historical Dissertations and Theses

In Exp. 1, 42 calves were fed milk replacer and then starter either with or without 1 ppm supplemental chromium (Cr) as Cr-picolinate. Neither Cr nor sex affected growth performance. With the exception of plasma nonesterified fatty acid concentrations (NEFA), weekly plasma metabolites were not affected by Cr or sex. Pre- and postfeeding plasma NEFA concentrations were lower in Cr-fed calves, but were not affected by sex. AU calves seemed to become less insulin sensitive with age, as plasma glucose became lower and insulin higher as calves became older. During i.v. glucose tolerance tests (IVGTT), calves cleared glucose faster at …

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An Analysis Of Factors Influencing The Teaching Of Biological Evolution In Louisiana Public Secondary Schools., Donald Wayne Aguillard Jan 1998

An Analysis Of Factors Influencing The Teaching Of Biological Evolution In Louisiana Public Secondary Schools., Donald Wayne Aguillard

LSU Historical Dissertations and Theses

Louisiana public school biology teachers were surveyed to investigate their attitudes toward biological evolution. A mixed method investigation was employed using a questionnaire and open-ended interviews. Results obtained from 64 percent of the sample receiving the questionnaire indicate that although teachers endorse the study of evolution as important, instructional time allocated to evolution is disproportionate with its status as a unifying concept of science. Two variables, number of college courses specifically devoted to evolution and number of semester credit hours in biology, produced a significant correlation with emphasis placed on evolution. The data suggest that teachers' knowledge base emerged as …

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Chiral Recognition With Polymerized Dipeptide Surfactants In Capillary Electrophoresis., Eugene Joseph Billiot Jan 1998

Chiral Recognition With Polymerized Dipeptide Surfactants In Capillary Electrophoresis., Eugene Joseph Billiot

LSU Historical Dissertations and Theses

The research presented in this dissertation involves the use and characterization of polymerized amino acid based surfactants for the enantiomeric separation of chiral compounds using capillary electrophoresis. The first section, Chapter 1, is an introduction to three topics which are relevant to the work presented in this manuscript. The topics include a brief discussion about chirality and chiral recognition, followed by a description of surfactants and micellar systems. The last part of the introduction pertains to capillary electrophoresis and the use of micellar electrokinetic chromatography for enantiomeric separation of chiral compounds. In Chapter 2, the effect of amino acid order …

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Spatial Variability Of Coastal Organic Soil Characteristics., L. Cecil Dharmasri Jan 1998

Spatial Variability Of Coastal Organic Soil Characteristics., L. Cecil Dharmasri

LSU Historical Dissertations and Theses

This dissertation is a part of the Louisiana NASA/EPSCoR (Experimental Program to Stimulate Competitive Research) global change research, which studied the fate of carbon and sediments within the Barataria Bay Basin, Louisiana. It studied water composition to assess seawater influence within the marsh. Ion exchange resin strips were used to study the effect of salinity and Chloride (Cl) on sulfate (SO4) reduction and their potential for water and soil analysis. Chloride dominated the water system and the Cl/SO 4 ratio can be used to assess the seawater influence. Resin extractable sulfur (S) predicted non-pyritic S fraction for the marsh soils. …

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Influence Of Diet And Genetic Strain On Desirable Flavors In Farm-Raised Catfish., Carol Ann Kelly Jan 1998

Influence Of Diet And Genetic Strain On Desirable Flavors In Farm-Raised Catfish., Carol Ann Kelly

LSU Historical Dissertations and Theses

This farm-raised catfish quality study measured desirable flavor attributes, Chickeny, Nutty, Fat Complex, Corn, Sweet, with the objective to determine effects of feed ingredients, time-on-diet and genetic strain. Overall flavor impact differences were tested by triangle tests. The diets were Casein-base reference feed by itself or partially substituted with: 10% catfish meal, 10% meat and bone meal, 10% rice bran, or 3% menhaden oil and commercial feed formulation. Fish were grown indoors to minimize environmental flavors for 70, 160, 210 and 318 days. The genetic strains evaluated were channel, albino channel, blue, hybrid channel x blue, and black bullhead catfish. …

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Moth Diversity In Louisiana Longleaf Pine Savannas And Mixed Mesophytic Hardwood Forests: Species Composition And Management Effects., Deborah Landau Jan 1998

Moth Diversity In Louisiana Longleaf Pine Savannas And Mixed Mesophytic Hardwood Forests: Species Composition And Management Effects., Deborah Landau

LSU Historical Dissertations and Theses

Two habitats, a mixed hardwood forest and a longleaf pine savanna, were selected for analysis of moth composition. Three studies assessed differences between moth diversity, efficiency of sampling intensities, and effects of management practices in these habitats. The first study compared diversity and community composition between the two habitats based on 4,337 moths representing 394 species. The mixed hardwood habitat contained 314 species and the longleaf pine 208. Species overlap between two longleaf pine sites was as low as overlap between longleaf pine and mixed hardwood habitats (38%). Differences in moth richness between habitats may be a reflection of differences …

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Airbirds: Adaptative Strategies To The Aerial Lifestyle From A Life History Perspective., Manuel Marin-Aspillaga Jan 1998

Airbirds: Adaptative Strategies To The Aerial Lifestyle From A Life History Perspective., Manuel Marin-Aspillaga

LSU Historical Dissertations and Theses

"Airbirds" are defined as those birds that are adapted to almost constant life on the wing and do not perch, except for breeding and roosting. They use the air as the only medium in which to find and gather food. One taxon meets that definition: the swifts (Apodidae). Foraging zones of airbirds can be segregated in terms of clutch size, commuting foraging distance, nestling period, and nestling feeding rate. This study looked at foraging behavior and nestling diet, incubation patterns and mode of development in cypseloidine swifts, that as a group has extreme life history patterns. In a temperate one-egg …

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Redefining Babes, Booze And Brawls: Men Against Violence. Towards A New Masculinity., Luoluo Hong Jan 1998

Redefining Babes, Booze And Brawls: Men Against Violence. Towards A New Masculinity., Luoluo Hong

LSU Historical Dissertations and Theses

Despite evidence that 90% of violent crimes are committed by men, higher education professionals and researchers still understand relatively little about the process by which mate students acquire the attitudes, knowledge, values and skills which serve as deterrents to perpetrating violence against women and against other men. Men Against Violence is a peer advocacy organization at a large, public Research I institution in the South which focuses on the special and unique responsibility men have to end violence. Through participation in a wide array of service learning, community action and leadership opportunities, MAV members challenge cultural norms which link masculinity …

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Beta-Carotene And Exercise Performance: Effects On Race Performance, Oxidative Stress, And Maximal Oxygen Consumption., Kim Edward Leblanc Jan 1998

Beta-Carotene And Exercise Performance: Effects On Race Performance, Oxidative Stress, And Maximal Oxygen Consumption., Kim Edward Leblanc

LSU Historical Dissertations and Theses

There is evidence in the literature that suggests a possible worthwhile role of antioxidants during athletic endeavors and exercise performance. Several studies have evaluated the antioxidant ability of beta-carotene and demonstrated a beneficial influence. However, these studies have investigated beta-carotene's effects within an antioxidant mixture which included other antioxidant vitamins. Consequently, this study attempted to isolate the antioxidant role of beta-carotene during exercise. Three parameters of beta-carotene influence were measured using eleven well-trained runners: serum malondialdehyde (MDA) concentration (a marker of free radical generation), 5000 meter race performance, and maximum oxygen consumption (VO2max). Subjects were tested using a double-blinded cross-over …

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The Nature Of Undergraduates' Conceptual Understanding Of Oxygen Transport And Utilization In Humans: Can Cardiopulmonary Simulation Software Enhance Learning Of Propositional Knowledge And/Or Diagnose Alternative Conceptions In Novices And Intermediates?, Dennis Robert Wissing Jan 1998

The Nature Of Undergraduates' Conceptual Understanding Of Oxygen Transport And Utilization In Humans: Can Cardiopulmonary Simulation Software Enhance Learning Of Propositional Knowledge And/Or Diagnose Alternative Conceptions In Novices And Intermediates?, Dennis Robert Wissing

LSU Historical Dissertations and Theses

The purpose of the this research was to explore undergraduates' conceptual development for oxygen transport and utilization, as a component of a cardiopulmonary physiology and advanced respiratory care course in the allied health program. This exploration focused on the student's development of knowledge and the presence of alternative conceptions, prior to, during, and after completing cardiopulmonary physiology and advanced respiratory care courses. Using the simulation program, SimBioSysTM (Samsel, 1994), student-participants completed a series of laboratory exercises focusing on cardiopulmonary disease states. This study examined data gathered from: (1) a novice group receiving the simulation program prior to instruction, (2) a …

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The Role Of Alginate Lyase In Pseudomonas Syringae Pathovar Phaseolicola., Charlie Mark Ott Jan 1998

The Role Of Alginate Lyase In Pseudomonas Syringae Pathovar Phaseolicola., Charlie Mark Ott

LSU Historical Dissertations and Theses

The plant pathogen responsible for halo blight in legumes, Pseudomonas syringae pathovar phaseolicola, produces an alginate exopolysaccharide which prevents desiccation and enhances the "water soaking" effect associated with pathogenesis. These bacteria demonstrated elevated extracellular alginate lyase activity during log growth and stationary phases in batch cultures. An analysis of the substrate specificity indicated enzymatic activity on both acetylated and non-acetylated alginate. The release of the enzyme(s) in log growth phase and the subsequent decrease in production in stationary phase have not been previously reported. Extracellular activity during rapid cell growth was confirmed by continuous culture in both nutrient broth and …

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Texts And Talk: A Close Look At Gender In Literature Discussion Groups., Peggy Sue Rice Jan 1998

Texts And Talk: A Close Look At Gender In Literature Discussion Groups., Peggy Sue Rice

LSU Historical Dissertations and Theses

This study investigated discourse according to gender-related patterns of eight sixth-grade students (four boys and four girls) as they discussed four realistic fiction short stories in peer-led discussion groups that alternated between same-sex and mixed-sex group compositions. Descriptive data were analyzed according to the constant comparative method of analysis. Quantitative analysis was used to determine discourse patterns in terms of frequency. Data were analyzed to answer the following questions: (1) Will the discourse patterns vary when the students discuss their responses in same-sex groups and mixed-sex groups? If so, in what ways will they vary? (2) Will gender differences be …

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The Selective Digital Integrator: A New Device For Modulated Polarization Spectroscopy., Aljosa Vrancic Jan 1998

The Selective Digital Integrator: A New Device For Modulated Polarization Spectroscopy., Aljosa Vrancic

LSU Historical Dissertations and Theses

A new device, a selective digital integrator (SDI), for the acquisition of modulated polarization spectroscopy (MPS) signals is described. Special attention is given to the accurate measurement of very small (AC component of interest $<$10$\sp{-3}$ x DC component), rapidly modulated ($\sim$50 kHz) signals at or below noise levels. Various data acquisition methods and problems associated with the collection of modulated signals are discussed. The SDI solves most of these problems and has the following advantages: it provides the average-time resolved profile of a modulated signal; it eliminates errors if the modulation is not sinusoidal; it enables separate measurements of the various phases of the signal modulation cycle; it permits simultaneous measurement of absorption, circular dichroism (CD) and linear dichroism (LD) spectra; it facilitates 3-D absorbance measurements; it has a wide gain-switching-free dynamic range (10 orders of magnitude or more); it offers a constant S/N ratio mode of operation; it eliminates the need for photomultiplier voltage feedback, and it has faster scanning speeds. The time-resolution, selectivity, wide dynamic range, and low-overhead on-the-fly data processing are useful for other modulated spectroscopy (MS) and non-MS experiments such as pulse height distribution and time-resolved pulse counting measurements. The advantages of the MPS-SDI method are tested on the first Rydberg electronic transitions of (+)-3-methylcyclopentanone. The experimental results validate the predicted SDI capabilities. However, they also point to two difficulties that had not been noted previously: the presence of LD in a gaseous sample and a pressure-dependence of the relative peak heights of the CD spectrum. Models for these anomalies are proposed. The presence of the oscillatory LD (but not an LD background) is explained with a sample cell model based on the observed polarization-dependent time-resolved profiles of transmitted light intensity. To obtain expressions for these intensities, a theoretical background, which provides a new approach to the treatment of light/matter interaction, is included as an Appendix. To explain the second anomaly, present only at high optical densities, a model based on the presence of scattered light is introduced and verified. The mode of correction for the scattering problem is outlined.

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Creativity And The Cathartic Moment: Chaos Theory And The Art Of Theatre., Robert E. Brooks Jan 1998

Creativity And The Cathartic Moment: Chaos Theory And The Art Of Theatre., Robert E. Brooks

LSU Historical Dissertations and Theses

This dissertation investigates the potential applications of the scientific paradigm known as "chaos theory" in the examination of dramatic theory. By illuminating the limitations of traditional Newtonian physics and Euclidean geometry, chaos theory conveys philosophical implications that transcend the scientific and provide suitable tools for describing cultural and artistic phenomena. These implications include emphasis on unpredictability, interaction and feedback, qualitative rather that quantitative analyses, and a nonlinear, continuous, even holistic perspective of systems traditionally viewed as dischotomous (such as order and disorder or part and whole). This study examines several standard works of dramatic theory, concentrating on the relationship of …

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Evaluation Of Chemical Treatments And Intrinsic Factors That Affect The Mutagenic Potential Of Aflatoxin B1-Contaminated Corn., Armando Burgos-Hernandez Jan 1998

Evaluation Of Chemical Treatments And Intrinsic Factors That Affect The Mutagenic Potential Of Aflatoxin B1-Contaminated Corn., Armando Burgos-Hernandez

LSU Historical Dissertations and Theses

In the present project the use of ammoniation and fermentation as an integrated process was studied in order to give aflatoxin-contaminated corn an alternative use. Aflatoxin-contaminated corn can be fermented to obtain fuel alcohol and decontaminated distiller's dried solid grains (DDSG) can be used for animal feed. The efficacy of a fermentation process, with the inclusion of ammonium persulfate, for the decontamination of aflatoxin B$\sb1$-contaminated yellow corn was studied, as well as the effect of peroxides on the ethanol production. Addition of 2.0% ammonium persulfate decreased the aflatoxin B$\sb1$ levels by 87%. Peroxides did not have an effect on ethanol …

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The Effects Of Pah-Contaminated Sediments On Benthic-Feeding Fishes And Their Associated Prey., Candace Gay Hinkle-Conn Jan 1998

The Effects Of Pah-Contaminated Sediments On Benthic-Feeding Fishes And Their Associated Prey., Candace Gay Hinkle-Conn

LSU Historical Dissertations and Theses

Subtidal sediments near Port Fourchon, Louisiana, USA, have been contaminated with produced water, as indicated by the levels of polycyclic aromatic hydrocarbons (PAH) for over four decades. Studies were undertaken to examine the effect of produced water/PAH on the potential for trophic transfer (from meiofauna and small macrofauna to benthic-feeding fishes) of sediment-bound contaminants. A survey of meiofaunal communities along a putative pollution gradient from the produced water outfall to a distance of 1 km found that meiofauna densities were significantly higher at the most contaminated sites ($\sim$10,000 ng PAH g$\sp{-1}$ dry sediment). The community at the most contaminated sites, …

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Serological And Molecular Biological Studies Of Marine Predator-Prey Systems., Marilyn J. Hoyt Jan 1998

Serological And Molecular Biological Studies Of Marine Predator-Prey Systems., Marilyn J. Hoyt

LSU Historical Dissertations and Theses

Two aspects of species identification were addressed; a molecular approach to identify anchovy larval and serological methods for prey detection in predator gut washes. Analysis of the pattern of restriction fragments of mitochondrial DNA (mtDNA) from adult anchovies from the Gulf of Mexico was employed to speciate four anchovy species. MtDNA isolated from white muscle of adult Anchoa mitchilli, A. hepsetus, A. nasuta and Engraulis eurystole produced an amplified 2.4 Kb DNA product when primers for NADH dehydrogenase 5 and 6 genes were used in polymerase chain reactions (PCR). Digestion of the amplified sequence with Dpn II produced a unique …

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Aflatoxin B(1) And Fumonisin B(1) Co-Contamination: Interactive Effects, Possible Mechanisms Of Toxicity, And Decontamination Procedures., Rebeca Lopez-Garcia Jan 1998

Aflatoxin B(1) And Fumonisin B(1) Co-Contamination: Interactive Effects, Possible Mechanisms Of Toxicity, And Decontamination Procedures., Rebeca Lopez-Garcia

LSU Historical Dissertations and Theses

The current study evaluated interactions between the mycotoxins aflatoxin B$\sb1$ (AFB$\sb1$) and fumonisin B$\sb1$ (FB$\sb1$) in pure systems as well as in corn. During storage at 25$\sp\circ$C with high moisture (ca. 50%), corn contaminated with Aspergillus flavus (L13) and/or Fusarium moniliforme (A00102) presented different aflatoxin and fumonisin levels. Toxin production/degradation varied over storage time (0-45 days). Evaluation of the mutagenicity of unifungal or bifungal corn extracts with the Salmonella/microsomal assay (tester strains TA-100 and TA-98) with metabolic activation (S9) showed positive mutagenic responses. Different ratios of pure AFB$\sb1$/FB$\sb1$ produced divergent mutagenic responses (tester strains TA-100 and TA-98) with S9. The …

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Behavior Of Red Snapper, Lutjanus Campechanus, In Relation To Trawl Modifications To Reduce Shrimp Trawler Bycatch., Donna Reeve Rogers Jan 1998

Behavior Of Red Snapper, Lutjanus Campechanus, In Relation To Trawl Modifications To Reduce Shrimp Trawler Bycatch., Donna Reeve Rogers

LSU Historical Dissertations and Theses

Behavioral responses of young-of-the-year red snapper, Lutjanus campechanus, to alterations in water flow were examined in the laboratory and the field in an effort to facilitate their release from shrimp trawls. Experiments with red snapper, collected by divers, were conducted in a racetrack flume. Four vertical and two horizontal mesh and solid panel types were examined. Four snapper (out of 96) escaped with vertical panels and thirteen fish (out of 48) exited with horizontal panels. Escapes occurred primarily with solid panels containing 0.95-cm holes drilled at 5-cm intervals. However, snapper that escaped with solid horizontal panels frequently went back into …

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Aspects Of Searching And Tunneling Behavior In Resource Utilization By The Formosan Subterranean Termite, Coptotermes Formosanus Shiraki., Justin Carl Hedlund Jan 1998

Aspects Of Searching And Tunneling Behavior In Resource Utilization By The Formosan Subterranean Termite, Coptotermes Formosanus Shiraki., Justin Carl Hedlund

LSU Historical Dissertations and Theses

Formosan subterranean termites, Coptotermes formosanus Shiraki (Isoptera: Rhinotermitidae), were acclimated with different masses of pine or no wood (control) and then allowed access to a thin sand filled tunneling chamber. As available pine increased, termite survival and food consumption increased but search tunnel volume decreased. Increased food size resulted in termites excavating fewer exploratory tunnels due to decreases in secondary and tertiary branch tunnels. An increase in food size also decreased the total length of a search tunnel network, due to decreases in primary and secondary branch order lengths. Search tunnel networks had proportionally more length devoted to primary tunnels …

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Reproductive Isolation Between Two Species Of Topminnow, Fundulus Olivaceus And F. Euryzonus., Thomas Allen Blanchard Jan 1998

Reproductive Isolation Between Two Species Of Topminnow, Fundulus Olivaceus And F. Euryzonus., Thomas Allen Blanchard

LSU Historical Dissertations and Theses

Fundulus olivaceus and F. euryzonus are sister species that commonly occur syntopically in the Amite and Tangipahoa River drainages in Louisiana and Mississippi. Although the habitats of the two species are quite similar, and the timing of their reproductive activity overlaps extensively, no natural hybrids between them have been documented. I examined physiological, as well as behavioral, factors that could potentially serve as effective isolating mechanisms between them. The courtship and spawning behaviors of the two species were relatively generalized and showed a number of similarities. Under forced mating conditions in which females were allowed to associate with heterospecific males …

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Characterization And Utilization Of Flavors From Undersized Crawfish., Feng Chen Jan 1998

Characterization And Utilization Of Flavors From Undersized Crawfish., Feng Chen

LSU Historical Dissertations and Theses

Undersized processed crawfish are proposed to be a resource for effective recovery of crawfish flavors. Tail puree from undersized crawfish was hydrolyzed using protease APL-440 through response surface methodology to enrich flavor production. Optimal hydrolytic conditions were determined to be pH $8{\sim}9,\ 65\sp\circ$C, 0.3% (V/W) enzyme/substrate ratio with the reaction maintained at 33.3% puree concentration over 60 min period. Effects of storage time and extraction method on the crawfish flavor profile were evaluated. Shorter storage time gave superior flavor stocks with less oxidized flavors. The shelf-life of frozen crawfish puree was at least six months. Atmospheric simultaneous distillation-solvent extraction (A-SDE) …

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Intraspecific Variation In Three Marsh Grasses In Response To Increased Flooding And Salinity., Jeannine Marie Lessmann Jan 1998

Intraspecific Variation In Three Marsh Grasses In Response To Increased Flooding And Salinity., Jeannine Marie Lessmann

LSU Historical Dissertations and Theses

Intraspecific variation in response to moderate levels of flooding and salinity stress was identified in Spartina patens, S. alterniflora, and Panicum hemitomon. This analysis enabled genotypes of each species to be selected for desired traits to enhance their function in restored systems, such as increased belowground biomass to stabilize soil substrates or increased aboveground biomass to enhance sedimentation. It was also determined that increased flood tolerance conferred a greater advantage for plant growth at moderate stress levels than did increased salt tolerance. However, this growth advantage was overridden by high salinity stress, and was greatly reduced by excessive flooding stress. …

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Pest Status Of The Fall Armyworm, Spodoptera Frugiperda (J. E. Smith), On Conventional And Transgenic Cotton Expressing The Bacillus Thuringiensis Cryia (C) Delta-Endotoxin: Development, Survival, And Host-Strain Influence., John Joseph Adamczyk Jr Jan 1998

Pest Status Of The Fall Armyworm, Spodoptera Frugiperda (J. E. Smith), On Conventional And Transgenic Cotton Expressing The Bacillus Thuringiensis Cryia (C) Delta-Endotoxin: Development, Survival, And Host-Strain Influence., John Joseph Adamczyk Jr

LSU Historical Dissertations and Theses

The pest status of the fall armyworm, Spodoptera frugiperda (J. E. Smith), including development and survival on conventional and transgenic Bacillus thuringiensis (Bt) cotton and host-strain influences, was examined in laboratory and field studies. Neonates (1st instars) were fed leaves from conventional (cv. DP 5415 and cv. DP 5690) and transgenic Bt (cv. NuCOTN 33$\rm\sp{B}$ and cv. NuCOTN 35$\rm\sp{B})$ cotton. There were no significant differences $(P>0.05)$ between cultivars in larval mortality and survival to the pupal and adult stages. However, times to pupation and adult eclosion were significantly longer $(P<0.05)$ for larvae fed transgenic Bt cotton compared to conventional cotton. In addition, larvae weighed significantly less $(P<0.05)$ when fed transgenic Bt cotton compared to conventional cotton. A study was conducted to determine when cotton bolls become tolerant to fall armyworm injury. Fifth instars were caged individually on bolls of various ages from conventional (cv. DP 5415) and transgenic Bt (cv. NuCOTN 33$\rm\sp{B})$ cotton to define the period of boll susceptibility to larval injury. For DP 5415 bolls, there was no significant linear relationship $(P>0.05)$ describing larval mortality or successful boll penetration as …

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Pliocene And Pleistocene Marine Ostracoda Of The Limon Basin, Costa Rica: A Record Of Paleoenvironmental Change., Pamela Frances Borne Jan 1998

Pliocene And Pleistocene Marine Ostracoda Of The Limon Basin, Costa Rica: A Record Of Paleoenvironmental Change., Pamela Frances Borne

LSU Historical Dissertations and Theses

Late Pliocene (3.8-3.6 Ma) and early Pleistocene (1.5-0.9 Ma) marine ostracodes of the Rio Banano, Quebrada Chocolate and Moin Formations (Limon Group) provide a detailed paleoenvironmental record for the Limon Basin, Costa Rica. The marine ostracode assemblages recovered from the Limon region do not provide evidence that the tropics cooled dramatically during the late Pliocene when the Northern Hemisphere was entering the Modern Ice Age. Paleoenvironmental interpretations are based on cluster analyses and a modern tropical ostracode analog analysis. Diverse ostracode assemblages of the middle Pliocene Rio Banano Formation are dominated by genera typical of the inner to middle neritic …

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An Analytical Approach To A Tree-Farm Wetland Study., Robert Cunninghame Davidge Jan 1998

An Analytical Approach To A Tree-Farm Wetland Study., Robert Cunninghame Davidge

LSU Historical Dissertations and Theses

Wetland delineation is important because federal and local government regulations limit permissible uses of wetlands. Federal delineation regulations are based upon the use of a manual jointly agreed upon by EPA, USACOE, and NRCS. The manual provides for classification of land as either wetland or non-wetland based upon the 3 criteria of soil, vegetation, and hydrology. No provision is made for gradation between categorical wetland and categorical non-wetland. Controversy has sometimes developed between landowners and environmentalists as to proper wetland classification; some delineations have been considered arbitrary. The analytical method of wetland appraisal provides a means of assigning continuous numerical …

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Localization And Biochemical Characterization Of The Cell Division Protein Ftsa In Escherichia Coli., Anand Immaneni Jan 1998

Localization And Biochemical Characterization Of The Cell Division Protein Ftsa In Escherichia Coli., Anand Immaneni

LSU Historical Dissertations and Theses

Cell division protein, FtsA, is an inner membrane protein with a putative ATP binding motif. Although FtsA has been studied genetically, it has not been characterized biochemically. Immunoelectron microscopy with FtsA polyclonal antibodies permitted FtsA to be within the cell. Since native FtsA is present in low amounts, the cellular level of this protein was increased by induction of ftsA from an overexpression plasmid before processing the cells for immunogold labelling. The immunogold particles localized FtsA to the inner cytoplasmic membrane. Immunogold labelling of cells overproducing C-terminal deleted FtsA, displayed the gold particles throughout the cytoplasm. This suggested that the …

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Physical And Chemical Properties Of Fibers Extracted From Sugarcane And Kenaf Rind., Simona Cristina Romanoschi Jan 1998

Physical And Chemical Properties Of Fibers Extracted From Sugarcane And Kenaf Rind., Simona Cristina Romanoschi

LSU Historical Dissertations and Theses

Sugar cane fibers were extracted from the rind of cane stalks with sodium hydroxide (NaOH) solutions of different concentrations, at atmospheric pressure, followed by a steam explosion. The extraction process was optimized using a central rotatable composite design, to study the influence of three reaction parameters (alkaline concentration, time of reaction and frequency of tumbling) on fiber bundle properties (weight, length, and tex). Tex was the objective function, with length as a constraint. Regression analysis indicated a quadratic polynomial response. Bleaching studies were conducted on sugar cane fibers extracted with 1.0N NaOH and on kenaf fibers mechanically processed only. Hydrogen …

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Experimental And Theoretical Study Of Dynamic Water Control In Oil Wells., Ephim I. Shirman Jan 1998

Experimental And Theoretical Study Of Dynamic Water Control In Oil Wells., Ephim I. Shirman

LSU Historical Dissertations and Theses

A dynamic water control, dubbed Downhole Water Sink (DWS) technology, is a well completion technique for production of hydrocarbons from reservoirs with bottom aquifer causing water coning. Typically, a DWS well is dually completed with top completion designated mostly for hydrocarbon production and bottom completion used for water drainage and coning control. Positions and flow rates of the completions are the DWS performance parameters to be determined by a process designer. This dissertation presents a theoretical and experimental study of DWS performance for various reservoir conditions and production schedules. A new mathematical model, developed in this work calculates steady state …

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