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1999

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Women's Health Issues In Baccalaureate Nursing Curricula., Karen Basham Moody Jan 1999

Women's Health Issues In Baccalaureate Nursing Curricula., Karen Basham Moody

LSU Historical Dissertations and Theses

The primary purpose of this study was to determine if, and how, selected women's health issues are included in baccalaureate nursing curricula in the United States. The study also assessed nursing faculty's perceptions of the importance of these selected women's health issues to nursing curricula. Two hundred sixty baccalaureate nursing programs were randomly selected from a population of 604 1998 National League for Nursing accredited baccalaureate nursing programs in the United States. A three-part researcher developed women's health survey instrument was used for data collection. The instrument consisted of questions pertaining to 19 women's health issues which were selected through …

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Barium In Water And Foraminiferal Shells: Indicator Of Oceanographic Conditions In The Gulf Of Mexico Since The Late Pleistocene., Thomas Peter Buerkert Jan 1999

Barium In Water And Foraminiferal Shells: Indicator Of Oceanographic Conditions In The Gulf Of Mexico Since The Late Pleistocene., Thomas Peter Buerkert

LSU Historical Dissertations and Theses

The Gulf of Mexico offers an appropriate setting for studying the chemical dynamics at the continent-ocean interface. In addition, its sediments preserve the climatic records of the past. This study employs Ba as a tracer to examine several aspects of modern Gulf oceanographic processes and seeks to unravel Gulf paleoceanography using Ba/Ca ratios from fossil foraminiferal shells. Comparison of dissolved Ba in the Mississippi and Atchafalaya River mixing zones suggests different Ba distributions can occur as a result of hydrodynamic and morphologic variability. Rapid Ba desorption from suspended material occurs near the Mississippi River, while Ba input from the shallow …

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Interactions On Minerals And Organic Materials Along The Salinity Gradient In Barataria Basin, Louisiana., Jessica Anne Kastler Jan 1999

Interactions On Minerals And Organic Materials Along The Salinity Gradient In Barataria Basin, Louisiana., Jessica Anne Kastler

LSU Historical Dissertations and Theses

Changes in the associations among mineral and organic materials in estuaries may control the nature and quantity of organic material (OM) preserved in sediment deposits or cycled in the water column. Estuarine sediment-OM attachments were examined using descriptive analyses and experiments to assess their response to salinity changes and the bioavailability of sedimentary OM. Desorption experiments compared the amount of organic carbon extracted from sediment in rinses of different salinity. Uptake experiments monitored changes in carbon and bacteria concentrations to compare the bioavailability of dissolved and sedimentary OM. Clay mineralogy, surface area and elemental analysis of suspended and deposited sediment …

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Studies On Cyclooxygenase-2 Expression In Lipopolysaccharide-Stimulated Macrophages., Byeong Churl Jang Jan 1999

Studies On Cyclooxygenase-2 Expression In Lipopolysaccharide-Stimulated Macrophages., Byeong Churl Jang

LSU Historical Dissertations and Theses

Cyclooxygenase (COX) is the key enzyme in the biosynthesis of prostaglandins (PGs) known as pro-inflammatory mediators. COX has two isoforms: the constitutively expressed COX-1 and the mitogen-inducible COX-2. It has been demonstrated that COX-2 expression is selectively induced by lipopolysaccharide (LPS) treatment after several hours in rat alveolar macrophages (Lee et al., 1992; Chanmugam et al., 1995). The mitogen-activated protein kinases [MAPKs; extracellular signal-regulated kinases (ERKs), P38, and c-jun N-terminal kinases (JNKs)], nuclear factor kappa B (NF-kB), and Lyn kinase are known to be activated in the early stages (within minutes) of LPS signaling pathways. In the current study, the …

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Women's Voices In Education: Two Jamaican Life Histories., Ethel L. King-Mckenzie Jan 1999

Women's Voices In Education: Two Jamaican Life Histories., Ethel L. King-Mckenzie

LSU Historical Dissertations and Theses

The main purpose of this study is to recover the marginalized voices of women educators in Jamaica by turning their oral life histories into text. It was not possible to interview all women educators in Jamaica so I have used the life histories of two women who were the 'first' women to take positions in educational leadership in two spheres that were once male dominated. Both women have made it to the zenith of the education profession. These women relate their life experiences and the meanings they give to their work as educators. Women have always played important roles in …

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Chromosomal Location Of Genes For Leafiness (Lfy1) And Susceptibility To Nicosulfuron (Nsf1) In Maize Genome., Orlando Jose Moreno Jan 1999

Chromosomal Location Of Genes For Leafiness (Lfy1) And Susceptibility To Nicosulfuron (Nsf1) In Maize Genome., Orlando Jose Moreno

LSU Historical Dissertations and Theses

Genes that may confer resistance to diseases, tolerance to plant stress, good stalk quality, high yield potential and/or other desirable attributes are important. The leafy gene (Lfy1Lfy1) discovered in 1971 in maize (Zea mays L.) is known to produce much higher yields in hybrids that possess it. These hybrids suffer much less stalk lodging than those with the non-leafy (lfy1 lfy1) gene. The location of the leafy gene to a chromosome arm could facilitate both its transfer from one genotype to another and its use in linkage studies and aid in completing the maize linkage map. The purpose of this …

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Null Codon-Based Models Of Synonymous And Nonsynonymous Substitution From A Phylogenetic Perspective., David A. Mcclellan Jan 1999

Null Codon-Based Models Of Synonymous And Nonsynonymous Substitution From A Phylogenetic Perspective., David A. Mcclellan

LSU Historical Dissertations and Theses

This dissertation focuses on the relationship between codon composition and the molecular evolution of protein-coding DNA sequences. Chapter 1 emphasizes the role of codon structure in determining patterns of nucleotide substitution, as well as the influence codon composition has on the evolution of the structure and function of the protein. The overall purpose of Chapter 1 is to establish the need to study molecular evolution at the codon level. In Chapter 2, the codon-degeneracy model (CDM) of molecular evolution is constructed. This model considers codon structure in terms of patterns of nucleotide site degeneracy. It allows the prediction of patterns …

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How Does Undergraduate College Biology Students' Level Of Understanding, In Regard To The Role Of The Seed Plant Root System, Relate To Their Level Of Understanding Of Photosynthesis?, James Gicheha Njeng'ere Jan 1999

How Does Undergraduate College Biology Students' Level Of Understanding, In Regard To The Role Of The Seed Plant Root System, Relate To Their Level Of Understanding Of Photosynthesis?, James Gicheha Njeng'ere

LSU Historical Dissertations and Theses

This research study investigated how undergraduate college biology students' level of understanding of the role of the seed plant root system relates to their level of understanding of photosynthesis. This research was conducted with 65 undergraduate non-majors biology who had completed 1 year of biology at Louisiana State University in Baton Rouge and Southeastern Louisiana University in Hammond. A root probe instrument was developed from some scientifically acceptable propositional statements about the root system, the process of photosynthesis, as well as the holistic nature of the tree. These were derived from research reviews of the science education and the arboriculture …

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Epidemiology Of Anthrax In The Kruger National Park, South Africa: Genetic Diversity And Environment., Kimothy Lyn Smith Jan 1999

Epidemiology Of Anthrax In The Kruger National Park, South Africa: Genetic Diversity And Environment., Kimothy Lyn Smith

LSU Historical Dissertations and Theses

The Kruger National Park, (KNP), in the Republic of South Africa, provides a unique opportunity to investigate interesting and unresolved aspects of the epidemiology of the disease anthrax. Anthrax is a disease of primarily mammals caused by the Gram-positive, rod-shaped, spore-forming bacteria Bacillus anthracis. Beyond it's great historical significance anthrax is clearly important in the world today. From a rich legacy of empirical investigations and observations in the form of ecological and epidemiological studies conducted around the world this work endeavors to distill and extract the essence of what biotic and abiotic factors of environment might be causally associated with …

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Effects Of Fluctuating Salinity, Nutritional State, And Temperature On Leptasterias Spp. From Little Port Walter, Alaska., Jeffrey William Tamplin Jan 1999

Effects Of Fluctuating Salinity, Nutritional State, And Temperature On Leptasterias Spp. From Little Port Walter, Alaska., Jeffrey William Tamplin

LSU Historical Dissertations and Theses

The effects of fluctuating salinity, nutritional state, and temperature on activity, oxygen consumption, feeding, and growth rates were analyzed on seasonally collected Leptasterias spp. (Echinodermata: Asteroidea) from Little Port Walter, AK. Leptasterias aspera and L. epichlora were collected on June 10, 1994, divided into size groups, and perivisceral fluid osmolality was measured every three hours during a 12 h 30-10-30‰S fluctuating cycle. The perivisceral fluid osmolality of larger individuals fluctuated less than that of smaller sea stars. The perivisceral fluid osmolality of small and large Leptasterias spp. closely tracks the ambient water osmolality during tidal cycles. Leptasterias spp. were collected …

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Behavior Of Bensulfuron-Methyl As Affected By Soil Factors And Rice Management Aspects., Randall Otto Wilde Jan 1999

Behavior Of Bensulfuron-Methyl As Affected By Soil Factors And Rice Management Aspects., Randall Otto Wilde

LSU Historical Dissertations and Theses

Multi-source regression models describing the control of alligatorweed with bensulfuron-methyl as influenced by rate and temperature were developed under field conditions. Temperature models describing the activity of bensulfuron-methyl at 21 to 84 g ai/ha on alligatorweed were linear 7 days after treatment (DAT) and quadratic 14 and 28 DAT. At 7 and 14 DAT, a minimum average temperature of 14 C was required for bensulfuron-methyl activity on alligatorweed. The temperatures for optimal alligatorweed control with bensulfuron-methyl at 14 DAT ranged from 21 to 24 C with rates of 21 to 84 g/ha. Temperatures for optimal alligatorweed control with bensulfuron-methyl at …

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Spatial Modeling Of Coastal Landscapes: Methodological And Scientific Applications., Mary Louise White Jan 1999

Spatial Modeling Of Coastal Landscapes: Methodological And Scientific Applications., Mary Louise White

LSU Historical Dissertations and Theses

A number of issues related to landscape scale ecological modeling of the wetlands of southern Louisiana are examined in this study. First, using geostatistical methods, a new contour map of the wetland habitats in the Terrebonne basin of southern Louisiana is constructed from data collected in 1994. This map is proposed as the best field verified habitat map of the Terrebonne basin and contains statistical confidence intervals associated with the habitat contours. Second, the problem of how to evaluate the success of a landscape model prediction is investigated. The multiple resolution goodness of fit parameter Ft(k) is evaluated in detail …

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Large Magnitude Sinusoidal Voltammetry For Reversible Electrochemical Reactions., Yide Chang Jan 1999

Large Magnitude Sinusoidal Voltammetry For Reversible Electrochemical Reactions., Yide Chang

LSU Historical Dissertations and Theses

Sinusoidal voltammetry, the current response of a simple reversible electrochemical reaction under a large magnitude sinusoidal potential, is investigated in this work. The ferricyanide/ferrocyanide (Fe(CN)6-3/-4 ) redox couple at a platinum electrode, which is known to be reversible, was measured using sinusoidal potentials. Theoretical analyses, including computer-simulation of sinusoidal voltammetry at various excitation potentials, are also presented. The results obtained are in good agreement with the theoretical analysis. One remarkable advantage of sinusoidal voltammetry is that the charging current accompanying the electrode process, which is the most significant components of the noise at a fast potential scan, may be discriminated …

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Systematics, Ecology, And Social Biology Of The Musk Duck (Biziura Lobata) Of Australia., Kevin Grant Mccracken Jan 1999

Systematics, Ecology, And Social Biology Of The Musk Duck (Biziura Lobata) Of Australia., Kevin Grant Mccracken

LSU Historical Dissertations and Theses

Musk Ducks (Biziura lobata) exhibit a number of unusual morphological and behavioral traits. The most notable of these include: greatly abducted hind-limbs for underwater swimming efficiency, extreme sexual size dimorphism and pronounced structural dimorphism, lek display activity, elaborate sexual display repertoires, and the distinctly non-waterfowl-like trait of provisioning young with all their food from the time of hatch until fledging. Despite such peculiarities and obvious theoretical potential in the areas of comparative morphology, sexual selection, and brood ecology, few studies of Musk Ducks have been undertaken, and those to date have been either small in scope and design, or focused …

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Soil Phosphorus Characteristics Of Natural And Created Wetlands In The Atchafalaya Delta, Louisiana., Matthew Emerson Poach Jan 1999

Soil Phosphorus Characteristics Of Natural And Created Wetlands In The Atchafalaya Delta, Louisiana., Matthew Emerson Poach

LSU Historical Dissertations and Theses

Quantitative comparisons of artificially created and natural wetlands are typically confounded by differences in wetland age, with created wetlands being younger than their natural counterparts. Observed differences between these wetlands may be attributed to either age differences or an inability to reproduce natural wetland characteristics. The objectives of this research were to: compare the phosphorus characteristics of similarly aged, created and natural wetlands in the Atchafalaya Delta, Louisiana and determine the controls over phosphorus retention in these wetlands. A phosphorus fractionation procedure was used to identify the phosphorus fractions in sediments from natural and artificially created wetlands in the Atchafalaya …

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Biological Diversity And Cultural Survival: Mopan Maya Traditional Culture And Environmental Change In Southern Belize., Michael Kenneth Steinberg Jan 1999

Biological Diversity And Cultural Survival: Mopan Maya Traditional Culture And Environmental Change In Southern Belize., Michael Kenneth Steinberg

LSU Historical Dissertations and Theses

This dissertation is a study of the causal relationship between the decline of cultural diversity and environmental diversity. My study investigates the larger-scale economic, political, and social factors that result in the rejection of traditional land use strategies and how these changing strategies ultimately lead to an overall decline in environmental diversity in the Mopan Maya landscape in southern Belize. Five Mopan Maya cultural biogeographic case studies are presented, including the management of maize diversity, the species composition and variability of kitchen gardens, swidden-fallow agroforestry practices, traditional bee keeping, and hunting game and habitat preferences. These topics were chosen because …

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College Biology Students' Conceptions Related To The Nature Of Biological Knowledge: Implications For Conceptual Change., Gloria Millie Apio Ameny Jan 1999

College Biology Students' Conceptions Related To The Nature Of Biological Knowledge: Implications For Conceptual Change., Gloria Millie Apio Ameny

LSU Historical Dissertations and Theses

Adequate understanding of the nature of science is a major goal of science education. Understanding of the evolutionary nature of biological knowledge is a means of reinforcing biology students' understanding of the nature of science. It provides students with the philosophical basis, explanatory ideals, and subject matter-specific views of what counts as a scientifically-acceptable biological explanation. This study examined 121 college introductory biology and advanced zoology students for their conceptions related to the nature of biological knowledge. A 60-item Likert-scale questionnaire called the Nature of Biological Knowledge Scale and student interviews were used as complementary research instruments. Firstly, the study …

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High School Biology Students' Participation In A Year-Long Sequence Of Analogical Activities: The Relationship Of Development Of Analogical Thought To Student Learning And Classroom Interactions., Marcella Wichser Hackney Jan 1999

High School Biology Students' Participation In A Year-Long Sequence Of Analogical Activities: The Relationship Of Development Of Analogical Thought To Student Learning And Classroom Interactions., Marcella Wichser Hackney

LSU Historical Dissertations and Theses

This research explored development of analogical thought through high school biology students' participation in a year-long sequence of analogical activities. Analogizing involves: selecting a familiar analog; mapping similarities and differences between the analog and less familiar target; making inferences from the analogy; evaluating validity of the inferences; and ultimately, understanding the biological target (Holyoak & Thagard, 1995). This investigation considered: student development of independence in learning through analogical thought, student learning of biology, the relationship between development of students' analogical thinking and students' learning of biology, and the quality of student interactions in the classroom. This researcher, as teacher participant, …

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Processes Controlling Nutrient Transport In The Southeastern Everglades Wetlands, Florida, United States Of America., Martha Ann Sutula Jan 1999

Processes Controlling Nutrient Transport In The Southeastern Everglades Wetlands, Florida, United States Of America., Martha Ann Sutula

LSU Historical Dissertations and Theses

The purpose of this dissertation was to investigate the processes that control material transport in the Southeastern (SE) Everglades and exchange with Florida Bay. Specifically, the objectives were to: (1) determine the factors controlling the spatio-temporal trends in material concentration and exchange; (2) estimate the annual nutrient and carbon export from the SE Everglades; and (3) determine the relative importance of surface water, atmospheric deposition, groundwater, and intrasystem cycling as sources and losses of nutrients to the watershed. Patterns in material exchange were observed for 2.5 years in three of five major creeks draining the SE Everglades. Statistical methods were …

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Production Of L-(+) Lactic Acid From Blackstrap Molasses By Lactobacillus Casei Subspecies Rhamnosus Atcc 11443., Narumol Thongwai Jan 1999

Production Of L-(+) Lactic Acid From Blackstrap Molasses By Lactobacillus Casei Subspecies Rhamnosus Atcc 11443., Narumol Thongwai

LSU Historical Dissertations and Theses

Lactobacillus casei subspecies rhamnosus grew on non-supplemented blackstrap molasses. The bacteria grew best at the optimal temperature of 40 +/- 2°C, and at pH 5.5. Addition of yeast extract to molasses shortened the lag phase and increased cell mass. In batch fermentations without pH control, the highest ratio of lactic acid produced to cell mass was 12 from non-supplemented molasses. For pH controlled batch fermentations, the ratio's of lactic acid produced/cell mass were 81, 79, 51 and 31 for 0, 0.2, 0.4 and 0.8% yeast extract supplementation, respectively. Non-supplemented molasses, 8% Brix, produced 28 +/- 2 g/l of lactic acid …

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Development Of Immunochemical Methods For Gossypol Analysis., Xi Wang Jan 1999

Development Of Immunochemical Methods For Gossypol Analysis., Xi Wang

LSU Historical Dissertations and Theses

Gossypol is a reactive polyphenolic compound present in the cotton plant. During cottonseed processing, gossypol can react with other compounds to form bound gossypol. Gossypol analyses using chemical methods do not always agree with its bioavailability to animal possibly because of various bound forms of gossypol with different stabilities in vivo and the (+/-)-gossypol enantiomers with different biological activities. The objectives of this research were to produce anti-gossypol antibodies and use antibodies to study gossypol chemistry and to analyze gossypol in cottonseed samples and cottonseed by-products. Polyclonal antibodies were produced from rabbits after they were immunized with gossypol-LPH (Limulus polyphemus …

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A Novel Approach To Dna Sequencing Employing Near -Ir Fluorescence Detection Coupled With Microscale Reaction Vessels With Capillary Gel Separations., Daryl Clifford Williams Jan 1999

A Novel Approach To Dna Sequencing Employing Near -Ir Fluorescence Detection Coupled With Microscale Reaction Vessels With Capillary Gel Separations., Daryl Clifford Williams

LSU Historical Dissertations and Theses

Electropherograms of oligonucleotides labeled with near-IR fluorescent dyes, separated by capillary gel electrophoresis (CGE) and detected using an ultrasensitive near-IR fluorescence detection system will be presented. A Universal M13 sequencing primer was labeled on the 5' end with a near-IR dye containing an isothiocyanate functional group. Comparison of the on-column detection limits in capillary gel electrophoresis for the near-IR-labeled sequencing primer to that of a visible fluorescein-labeled primer indicated improved sensitivity for the near-IR case. The detection limit was found to be 3.4 x 10-20 moles (SNR = 3) for the near-IR-labeled primer while the on-column detection limit for the …

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Risk Management Of Aflatoxin Through Mutagenic Potential Modification And Toxin Formation By Intrinsic Components In Food., Syed Shahid Ali Jan 1999

Risk Management Of Aflatoxin Through Mutagenic Potential Modification And Toxin Formation By Intrinsic Components In Food., Syed Shahid Ali

LSU Historical Dissertations and Theses

Aflatoxins are the secondary metabolites of Aspergillus flavus and their presence in food and feed crops is unavoidable. This study evaluates the antimutagenic properties of phytic and linoleic acids in aflatoxin-affected food. A reduction in the number of revertants was a function of an increased concentration of phytic/linoleic acids and phosphotidylinositol in the Salmonella/microsomal mutagenicity assay (tester strains TA-100 and TA-98) with and without metabolic activation (S-9). Linoleic acid (10 and 100 mug/plate) and phosphotidylinositol (25mug/plate) were antimutagenic against most of the mutagens tested. Although a reduction in the number of revertants was observed in the phytic acid treatments, the …

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Phylogeography Of Two Loligo Squid (Cephalopoda: Myopsida) In The Gulf Of Mexico And The Northwestern Atlantic Ocean., Scott William Herke Jan 1999

Phylogeography Of Two Loligo Squid (Cephalopoda: Myopsida) In The Gulf Of Mexico And The Northwestern Atlantic Ocean., Scott William Herke

LSU Historical Dissertations and Theses

Based on restriction fragment length polymorphisms (RFLP) in mitochondrial DNA, the population structures of two species of Loligo squid were analyzed in the context of the classic Gulf of Mexico-Atlantic Ocean phylogeographic pattern. A 709-bp fragment of the cytochrome c oxidase (subunit I) gene was amplified by PCR from 356 L. pealei and 431 L. plei. Between latitudes 25°N and 43°N, each species had three common (>5% frequency) haplotypes and many rare haplotypes. Sequence data from all haplotypes indicated that nucleotide divergence between the two species ranged from 13.7 to 15.0% (transition-transversion ratio of ∼1.5; two inferred amino acid …

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Increased Nutritional Value And Oxidative Stability Of Restructured Beef Roasts With Purified Extracts From Rice Bran., Joo-Shin Kim Jan 1999

Increased Nutritional Value And Oxidative Stability Of Restructured Beef Roasts With Purified Extracts From Rice Bran., Joo-Shin Kim

LSU Historical Dissertations and Theses

The effects of semi-purified extracts of rice bran were studied in restructured beef roasts to increase nutritional value and oxidative stability. Crude rice bran oil at 0, 1, and 2% (w/w) was added to restructured beef roasts that were stored at 4°C and analyzed at 0, 7, and 14 d. Saturated fatty acid to unsaturated fatty acid (SFA/UFA) ratio decreased, vitamin E vitamers increased (p < 0.05), and cholesterol decreased in the beef roasts with rice bran oil. Thiobarbituric acid reactive substances (TBARs) numbers were lower (p < 0.05) in the beef roasts with rice bran oil after 7 days of storage and the cholesterol oxidation product, 7-ketocholesterol, decreased in a similar manner. The addition of 2% rice bran oil (RBO) was effective in increasing nutritional value and reducing the level of oxidative degradation. Beef roasts containing either rice fiber (RF) or RF/RBO had higher oxidative stability (p < 0.05) during storage (0, 4, and 8 d) compared to control roasts, with no additive. TBARs value and 7-ketocholesterol of beef roasts with RF and RF/RBO were lower (p < 0.05) than those of the control during storage. SFA/UFA ratio was significantly reduced in beef roasts with additives, whereas vitamin E vitamers and UFA were higher (p < 0.05) in the roasts with RF/RBO. Beef roasts containing RF and RBO were acceptable to consumers in sensory attributes. Cholesterol autoxidation was examined in an aqueous meat model system with different levels of nonsaponifiable fraction from rice bran (0, 700, 1400, and 2100 ppm). The effect of nonsaponifiable fraction was determined at 4 h intervals for 16 h at pH 5.5 and 80°C. Increased oxidation time reduced (p < 0.05) total vitamin E vitamers and cholesterol concentration. Oryzanol was not significantly reduced with the 2100 ppm treatment after 4 h cholesterol oxidation. An increase in the nonsaponifiable fraction resulted in a decrease (p < 0.05) in the formation of 7-ketocholesterol. The highest level of additive (2100 ppm) was the most effective in inhibiting cholesterol autoxidation; the order of inhibition was 91.7% (2100 ppm) > 81.8% (1400 ppm) > 63.1% (700 ppm).

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Diallel Analysis And Molecular Genetics Of Ten Influential Upland Cotton Cultivars., Huangjun Lu Jan 1999

Diallel Analysis And Molecular Genetics Of Ten Influential Upland Cotton Cultivars., Huangjun Lu

LSU Historical Dissertations and Theses

The most influential cultivars from 16 cotton breeding programs were identified based on the analysis of the pedigree of 260 cultivars released between 1970 to 1990. A diallel cross containing ten parents and 45 F 1s (no reciprocals) was conducted to investigate general (GCA) and specific (SCA) combining ability for yield, yield components, and fiber properties of ten influential cultivars. The ten cultivars varied significantly for all the traits except for seed cotton yield and fiber length uniformity. Significant or highly significant GCA effects were detected for 11 of 12 traits studied. This indicates important additive gene action for the …

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Isolation Of Antimutagenic Compounds In Corn And Cottonseed., Henry Njapau Jan 1999

Isolation Of Antimutagenic Compounds In Corn And Cottonseed., Henry Njapau

LSU Historical Dissertations and Theses

Food, which ensures the sustenance of life, has also been implicated in the development or prevention of numerous diseases including cancer. Cancer may be a result of hereditary factors or genomic instability induced by DNA damage, from the intrinsic chemistry of cells or extrinsic factors like aflatoxin B1. Aflatoxin B1, produced by Aspergillus flavus and Aspergillus parasiticus, is a common contaminant of corn and cottonseed and a proven mutagen and animal carcinogen. Increased scientific knowledge and establishment of regulation have reduced but not eliminated exposure to aflatoxin B1. Complete elimination may be uneconomical for producers and may deprive consumers of …

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Characterization Of Solidification/Stabilization Of Chromium Wastes In Cement Matrix., Aijun Zhang Jan 1999

Characterization Of Solidification/Stabilization Of Chromium Wastes In Cement Matrix., Aijun Zhang

LSU Historical Dissertations and Theses

A cement-based solidification/stabilization (S/S) system of Cr wastes treatment has been studied in this program. A combination of the two techniques; namely reduction of Cr(VI) to Cr(III) and simultaneous immobilization within a cement matrix, has been found to be effective and practical to treat Cr wastes. Cr(VI) can not be easily and effectively-immobilized in the S/S system unless being reduced to Cr(III). Ferrous compounds are used as reducing reagents. The reduction not only removes the toxic Cr(VI) species but also results in the low-solubility precipitation of (CrxFe 1-x) (OH)3(s) in the S/S system. Long-term and short-term samples were tested through …

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Sire Differences For Growth And Carcass Traits Of Purebred Brahman Steers., Trent Smith Jan 1999

Sire Differences For Growth And Carcass Traits Of Purebred Brahman Steers., Trent Smith

LSU Historical Dissertations and Theses

Purebred Brahman steers (n = 169) sired by 23 Gray and 8 Red Brahman bulls were evaluated for postweaning growth and carcass traits. Spring-born paternal half-sib male calves were purchased from private producers at weaning, backgrounded, and grazed on ryegrass for an average of 161 d. Following grazing, the steers were shipped to a commercial feedlot in south Texas for feeding. Steers were slaughtered in groups of about 45 head when they reached an approximate average endpoint weight of 530 kg and 1 cm backfat. All carcasses were subjected to high voltage electrical stimulation during slaughter. After a 24 hr …

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Production Of Transgenic Eastern Oysters., John Terrell Buchanan Jan 1999

Production Of Transgenic Eastern Oysters., John Terrell Buchanan

LSU Historical Dissertations and Theses

The eastern oyster, Crassostrea virginica, supports a valuable industry in the United States and Louisiana. In recent years this industry has been plagued by diseases, creating interest in the use of gene transfer to produce oysters capable of eliminating pathogens. The goal of this work was to develop techniques for laboratory research of eastern oysters, and for transfer of genes to oyster gametes, larvae, and adults. Cell culture provides an effective alternative to work in whole animals. Cell attachment and spreading on various culture substrates was improved, and poly-D-lysine was identified as a superior substrate. Toxicity of the antibiotic G418 …

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