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1998

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Gulf Coast Research Laboratory: A Mississippi Academy, Linda Skupien, Joyce M. Shaw Jan 1998

Gulf Coast Research Laboratory: A Mississippi Academy, Linda Skupien, Joyce M. Shaw

Gulf and Caribbean Research

A brief overview of the creation and growth of the Gulf Coast Research Laboratory, this article traces the institution’s history and its strong relationship with the Mississippi Academy of Sciences. The Mississippi Academy of Sciences officially dedicated the Gulf Coast Research Laboratory (GCRL) with the opening of the first summer session at Magnolia State Park in Ocean Springs, Mississippi, on August 28, 1947. Mississippians in scientific and educational circles had worked for two decades toward creating a research and educational laboratory focused on the state’s marine and coastal environments. The Academy’s priorities were scholarly research and education. Political leaders were …

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Salinity Action Plan : Wetland Vegetation Monitoring, 1997/1998, G. Ogden, R. H. Froend Jan 1998

Salinity Action Plan : Wetland Vegetation Monitoring, 1997/1998, G. Ogden, R. H. Froend

Research outputs pre 2011

This report represents the vegetation component of a project designed to provide on-going monitoring of wetland salinity and biological resources in wetlands of the agricultural zone of south-west Western Australia. Maintenance of wetland biological diversity in the agricultural zone is one of the major objectives of the Salinity Action Plan. Due to their low position in the landscape, wetlands are the habitat most affected by salinisation...

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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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The Physiological And Psychological Responses To Submaximal Exercise At Different Times In Renal Disease Patients., Marta Amaral-Melendez Jan 1998

The Physiological And Psychological Responses To Submaximal Exercise At Different Times In Renal Disease Patients., Marta Amaral-Melendez

LSU Historical Dissertations and Theses

This study investigated cardiorespiratory, hematological, and psychological responses to acute submaximal exercise, and recovery in end stage renal disease patients. Five African-American males on hemodialysis, were randomly assigned to three exercise treatments (30 minutes on the treadmill at 60% VO$\sb2$ peak): pre dialysis (2 hours before), post dialysis (1 hour after), and off dialysis (24 hours after last dialysis). The cardiorespiratory (CR) variables were: ventilation (V$\sb{\rm E}$), oxygen consumption (VO$\sb2$), carbon dioxide production (VCO$\sb2$), respiratory exchange ratio (R), and kilocalories (KCAL/min). The hematological variables were: blood urea nitrogen (BUN), creatinine (Cr), albumin (Al), total protein (Tp), glucose (Gl), sodium (Na$\sp{++}$), …

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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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The Interactions Among The Subunits Of The Mcrbc Restriction System In E. Coli., Loganayaki Ganesh Jan 1998

The Interactions Among The Subunits Of The Mcrbc Restriction System In E. Coli., Loganayaki Ganesh

LSU Historical Dissertations and Theses

The McrBC system of Escherichia coli K12 restricts DNA containing modified cytosines within specific sites. The modified cytosines recognized may be 5-hydroxymethylcytosine, N$\sp4$-methylcytosine or 5-methylcytosine. In the mcrBC operon, the mcrB gene is expressed to produce the McrB$\sb{\rm L}$ protein (51 kDa) and the McrB$\sb{\rm S}$ protein (33kDa), which is translated from an inframe internal translation start site and lacks the N-terminal 161 amino acids of the long product. The McrC protein is a 39kDa protein and is required for the cleavage of most methylated substrates. Using a MalE-McrB$\sb{\rm L}$ fusion protein, the endonucleolytic McrB$\sb{\rm L}$ subunit was shown to …

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A Conceptual And Empirical Approach For Valuing Biodiversity: An Estimate Of The Benefits Of Plant And Wildlife Habitat Preservation In The Tensas River Basin., Jack Coburn Isaacs Jan 1998

A Conceptual And Empirical Approach For Valuing Biodiversity: An Estimate Of The Benefits Of Plant And Wildlife Habitat Preservation In The Tensas River Basin., Jack Coburn Isaacs

LSU Historical Dissertations and Theses

This research estimated the passive use value of local species biodiversity in the Tensas River basin, a section of the Lower Mississippi River Valley. This research employed the contingent valuation method in eliciting willingness to pay for biodiversity conservation using the habitat needs of an umbrella species as a basis for valuation. This study designed and implemented the Lower Mississippi Valley Plant and Wildlife Survey for primary data collection. The sample included 1,351 households drawn from a hunting permit lottery conducted by the Tensas River National Wildlife Refuge and 3,044 households drawn at random from Louisiana, Arkansas, and Mississippi. The …

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Detection Of Mechanisms Of Profenofos Resistance In The Tobacco Budworm, Heliothis Virescens (F.)., John Ambrose Harold Jan 1998

Detection Of Mechanisms Of Profenofos Resistance In The Tobacco Budworm, Heliothis Virescens (F.)., John Ambrose Harold

LSU Historical Dissertations and Theses

Biochemical and physiological mechanisms of profenofos resistance in laboratory and field populations of the tobacco budworm, Heliothis virescens (F.) were studied. High frequencies of profenofos resistance were recorded in all field-collected strains and were strongly correlated with esterase (EST) activity and moderately correlated with glutathione S-transferase activity. Mean levels of acetylcholinesterase (AChE) sensitivity to inhibition by chlorpyrifos oxon were lower in some field strains than levels in an insecticide-susceptible strain; however, AChE sensitivity and resistance were poorly correlated in all field strains. There was no correlation between resistance and the activities of P450-monooxygenase or glutathione S-transferase measured. Studies with laboratory-selected …

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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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Identification Of Antigens Of Edwardsiella Ictaluri, The Causative Agent Of Enteric Septicemia Of Catfish (Esc)., Michelle Marie Moore Jan 1998

Identification Of Antigens Of Edwardsiella Ictaluri, The Causative Agent Of Enteric Septicemia Of Catfish (Esc)., Michelle Marie Moore

LSU Historical Dissertations and Theses

Edwardsiella ictaluri, causative agent of enteric septicemia of catfish (ESC), is the primary bacterial pathogen of commercially produced channel catfish (Ictalurus punctatus). The purpose of this study was to make progress towards development of a successful ESC vaccine by generating and characterizing a pool of E. ictaluri antigens and determining if they were protective against ESC in catfish. Antigenic protein expression was evaluated in E. ictaluri cells under different conditions of growth using two-dimensional polyacrylamide gel electrophoresis (2D-PAGE) and western blotting with pooled convalescent catfish serum (CCS). Results showed protein bands separated by one-dimensional PAGE may consist of one or …

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Purification And Antioxidant Properties Of Rice Bran (Gamma)-Oryzanol Components., Zhimin Xu Jan 1998

Purification And Antioxidant Properties Of Rice Bran (Gamma)-Oryzanol Components., Zhimin Xu

LSU Historical Dissertations and Theses

A high purity $\gamma$-oryzanol was obtained from crude rice bran oil using a normal phase preparative scale HPLC. It was used in implementing a reverse phase HPLC method for separating each individual component of $\gamma$-oryzanol present in rice bran oil. Ten fractions were isolated in the reverse phase HPLC method. The ten components of $\gamma$-oryzanol were identified. Three of these, cycloartenyl ferulate, 24-methylene cycloartanyl ferulate, and campesteryl ferulate, were major components of $\gamma$-oryzanol. The yield of $\gamma$-oryzanol without saponification was significantly higher than that with saponification in solvent extraction. The solvent mixture with 50% hexane and 50% isopropanol (v/v.) at …

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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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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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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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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 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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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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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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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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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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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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Beliefs And Practices Of Middle School Language Arts Teachers., Suzan Anderson Jan 1998

Beliefs And Practices Of Middle School Language Arts Teachers., Suzan Anderson

LSU Historical Dissertations and Theses

The purpose of this study is to examine the instructional beliefs and practices of middle school language arts teachers as they relate to developmental appropriate/inappropriate instruction. Developmentally appropriate instruction is defined as matching the curricula to the level of children's emerging mental abilities. If the learner is seen as a growing individual with developing abilities, then the aim of education should be to facilitate this development. This in turn means that the curricula must be studied and analyzed to determine that level of mental ability that is required to comprehend curriculum materials (Elkind, 1970). There is some concern that what …

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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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Rapid Assessment Of The Bacteriological Quality Of Milk By The Use Of Adenosine Triphosphate Bioluminescence., Pushpa John Samkutty Jan 1998

Rapid Assessment Of The Bacteriological Quality Of Milk By The Use Of Adenosine Triphosphate Bioluminescence., Pushpa John Samkutty

LSU Historical Dissertations and Theses

Raw milk samples (n = 246) and pasteurized milk samples (n = 104) were analyzed to determine adenosine triphosphate (ATP) and compared with the standard plate count (SPC). An ATP filtration method was used to filter milk samples prior to ATP determination, which was measured in relative light units (RLU). The ATP assay took approximately 7 minutes to complete and could allow rapid prediction of SPC which is a measure of raw milk quality. Linear regression analysis was performed on data from three raw milk treatments defined as; fresh milk samples, samples preliminarily incubated at 12.8 and 15.6$\sp\circ$C for 18 …

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