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Studies Of V-Nitrogenase From Azotobacter Vinelandii: Structural Variations, Temperature And Solvent Effects., Carol Zembiak Blanchard Jan 1995

Studies Of V-Nitrogenase From Azotobacter Vinelandii: Structural Variations, Temperature And Solvent Effects., Carol Zembiak Blanchard

LSU Historical Dissertations and Theses

When Q-Sepharose was used in the purification of the V-nitrogenase proteins from Azotobacter vinelandii, an increase in resolution was observed which resulted in a separation of the nitrogenase component 1 protein (Av1$\sp\prime$) into two forms, labeled Av1$\sp\prime\sb{\rm A}$ and Av1$\sp\prime\sb{\rm B}.$ Even though both forms possessed the same enzymatic behavior, Av1$\sp\prime\sb{\rm A}$ exhibited a lower specific activity and migrated during gel filtration with an apparent lower molecular weight than Av1$\sp\prime\sb{\rm B}.$ Furthermore, SDS-polyacrylamide gel electrophoresis showed different relative compositions of the two major subunits of both forms with Av1$\sp\prime\sb{\rm A}$ possessing a trimer $(\alpha\beta\sb2)$ pattern compared to the tetramer $(\alpha\sb\beta\sb2)$ …

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The Relationship Between The Accuracy Of Certain "Generalized" Body Density Prediction Equations And Indices Of Fatness, Body Physique/Proportionality And Fat Distribution., Christopher Melancon Hearon Jan 1995

The Relationship Between The Accuracy Of Certain "Generalized" Body Density Prediction Equations And Indices Of Fatness, Body Physique/Proportionality And Fat Distribution., Christopher Melancon Hearon

LSU Historical Dissertations and Theses

There is a need to eliminate the least accurate of the existing equations for anthropometrical body density prediction and support for the use of specific prediction equations over generalized equations. The purpose of the investigation was to examine the accuracy of the Jackson-Pollock (JP) and Durnin-Womersley (DW) generalized anthropometrical body density prediction equations in relation to indices of overall fatness, regional fat distribution and body proportionality. The relationships between prediction accuracy (predicted body density minus hydrodensitometric estimate of body density) and three mass/stature indices (total fatness indices), waist-to-hip circumference ratio (WC/HC)(android/gynoid fat distribution) and the three components of the Heath-Carter …

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Molecular Cloning, Sequencing, And Regulation Of The Rhodobacter Capsulatushemb Gene., Karl Joseph Indest Jan 1995

Molecular Cloning, Sequencing, And Regulation Of The Rhodobacter Capsulatushemb Gene., Karl Joseph Indest

LSU Historical Dissertations and Theses

The common tetrapyrrole pathway in the photosynthetic bacterium, Rhodobacter capsulatus, is responsible for the synthesis of bacteriochlorophyll, heme, vitamin B-12, and siroheme. The common portion of this pathway is regulated up to 100-fold by changes in oxygen tension. This regulation is accomplished by controlling the intracellular level of porphobilinogen. One way in which porphobilinogen levels could be controlled is by regulating the synthesis of porphobilinogen. Porphobilinogen synthase, encoded by the hemB gene, is the second enzyme in the common tetrapyrrole pathway that catalyzes the dimerization of 5-aminolevulinic acid to form the monopyrrole porphobilinogen. In order to further investigate the mechanism …

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Elucidation And Modulation Of Ceb Metabolism In Fischer 344 Rats: Possible Mechanisms Of Toxicity And Anticarcinogenicity., Judith Sara Prescott-Mathews Jan 1995

Elucidation And Modulation Of Ceb Metabolism In Fischer 344 Rats: Possible Mechanisms Of Toxicity And Anticarcinogenicity., Judith Sara Prescott-Mathews

LSU Historical Dissertations and Theses

The ability of acivicin (AT-125), probenecid, and aminooxyacetic acid (AOAA), to ameliorate 1-cyano-3,4-epithiobutane (CEB)-induced nephrotoxicity and karyomegaly was evaluated by histopathology and histomorphometry. Epithelial cell necrosis and karyomegaly were observed in the renal proximal tubules at 24 and 48 hours in all of the treated groups with the exception of AOAA pretreated rats at 24 hours. A predominant urinary metabolite of CEB was identified as the mercapturate, N-acetyl-S-(4-cyano-2-thio-1-butyl)-cysteine. Evidence of other urinary metabolites was also demonstrated. The influence of inhibitors on the GSH-enhancing effect of CEB was determined through measurement of tissue GSH levels and $\gamma$-glutamyl-cysteine synthetase (GCS) activity. Hepatic …

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Boal And Theatre Of The Oppressed: A Performance-Centered Inquiry Of Eating And Body Image., Leigh Anne Howard Jan 1995

Boal And Theatre Of The Oppressed: A Performance-Centered Inquiry Of Eating And Body Image., Leigh Anne Howard

LSU Historical Dissertations and Theses

Building upon the scholarly tradition that performance is a valuable pedagogical tool, I documented how six performers developed personal awareness, critical consciousness, and the ability to take action as a result of participating in a performance process. I designed a three-stage performance process. During the first phase of the process, focus group discussions, participants exhibited little awareness of their specific eating habits or the cultural constructedness of those habits. As they completed the first phase, they became more aware of their behaviors, and they began to identify food's social function. At the second stage, rehearsal sessions, six performers began to …

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Transcriptional Studies Of The Muscle-Specific Expression Of The Rabbit Muscle Phosphofructokinase Gene., Haiqing Fu Schiltz Jan 1995

Transcriptional Studies Of The Muscle-Specific Expression Of The Rabbit Muscle Phosphofructokinase Gene., Haiqing Fu Schiltz

LSU Historical Dissertations and Theses

The rabbit muscle phosphofructokinase (RM-PFK) gene is predominantly expressed in skeletal muscle. Its muscle-specific transcription was investigated using transient transfection studies, electrophoretic mobility shift assays, and DNaseI footprinting experiments. The evidence presented here provides the first example of the myogenic basic-Helix-Loop-Helix proteins regulating a gene that encodes a glycolytic enzyme. The 3 kb 5$\sp\prime$-flanking sequence of this gene directed the expression of the chloramphenicol acetyltransferase gene in muscle and non-muscle cells. MyoD, Myf5, and myogenin exhibited differential transactivation capabilities. MyoD had the most pronounced transactivational effect, and its N-terminal transactivation domain and the basic DNA-binding region were required for its …

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The Rabbit Muscle Phosphofructokinase Gene: Six Types Ofmrnas Are Tissue-Specifically Expressed By Multiple Promoters And Alternative Splicing., Shouhua Xiao Jan 1995

The Rabbit Muscle Phosphofructokinase Gene: Six Types Ofmrnas Are Tissue-Specifically Expressed By Multiple Promoters And Alternative Splicing., Shouhua Xiao

LSU Historical Dissertations and Theses

Phosphofructokinase (ATP:Fructose-6-phosphate 1-phospho-transferase, EC 2.7.1.11, PFK) catalyzes the phosphorylation of fructose 6-phosphate to generate fructose 1,6-bisphosphate, the rate-limiting step of glycolytic pathway. Li et al. (1990) have identified two cDNAs for the rabbit muscle PFK with an identical coding regions but different 5$\sp\prime$ untranslated regions (UTRs). In this dissertation research, six cDNAs for the rabbit muscle PFK mRNAs were cloned. These cDNAs are different in their 5$\sp\prime$ UTRs but have an identical open reading frame. The transcription initiation sites of two downstream promoters of this gene have been determined. A proximal promoter (Pa) is TATA-less and 86 bp upstream of …

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Synthesis Of An Anthracenebis(Beta-Ketoenamine) Ligand And Its Cofacial Binuclear Metal Complexes., Maria Del Rosario Benites Jan 1995

Synthesis Of An Anthracenebis(Beta-Ketoenamine) Ligand And Its Cofacial Binuclear Metal Complexes., Maria Del Rosario Benites

LSU Historical Dissertations and Theses

Following our studies of cofacial binuclear transition metal complexes, such as $\rm Cu\sb2(XBA)\sb2$ (see below), we became interested in the synthesis of a more rigid ligand, ABIH$\sb2$ which contains a 1,8-anthracene bridge. This new ligand, whose chelating moieties are constrained to be cofacial, should enable us to obtain a wide variety of cofacial bimetallic complexes such as 1, with controllable environments around the metal centers, for synthesis of multi-metal redox active catalysts.(DIAGRAM, TABLE OR GRAPHIC OMITTED...PLEASE SEE DAI). Three routes have been pursued to synthesize the anthracene-based ligand. Using organometallic derivatives of 3,5-dimethylisoxazole as acetylacetone synthons, the bis($\beta$-ketoenamine) ABIH$\sb2$ was …

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A Study Of Differences In Binding Of Hepatic Nuclear Proteins To The Upstream Region Of Glucocorticoid Regulated Tyrosine Aminotransferase Gene In Lean And Obese Rats., Huijun Dong Jan 1995

A Study Of Differences In Binding Of Hepatic Nuclear Proteins To The Upstream Region Of Glucocorticoid Regulated Tyrosine Aminotransferase Gene In Lean And Obese Rats., Huijun Dong

LSU Historical Dissertations and Theses

Glucocorticoids are required for the development of all forms of experimental obesity. Studies on Zucker fa/fa rats have revealed that the obese Zucker rat is hyper-responsive to the effects of glucocorticoids. This excessive response may result from an alteration in level or activity of a transcription factor in nuclei of obese fa/fa rat. Evidence from gel retardation assays using DNA fragments from the upstream region of glucocorticoid regulated tyrosine aminotransferase (TAT) gene and the nuclear extracts from obese and lean rats showed in this study that an increased amount of DNA fragment was shifted by nuclear extracts from obese rats …

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Effects Of Exogenous Female Sex Hormones On Food Intake, Macronutrients And Body Weight In The Ovariectomized Postbreeder Female Rat., Jan Barton Hamilton Jan 1995

Effects Of Exogenous Female Sex Hormones On Food Intake, Macronutrients And Body Weight In The Ovariectomized Postbreeder Female Rat., Jan Barton Hamilton

LSU Historical Dissertations and Theses

Hormone replacement therapy (HRT) is chosen by a growing segment of the postmenopausal population. Mid-life body weight gain is perceived to increase further with exogenous HRT. To examine hormonal effects on caloric intake (CI), carbohydrate (CHO), FAT, protein (PRO), chocolate and body weight (BW) in a female model, Sprague-Dawley postbreeder (n = 55) rats (10 mos., 10 litters of pups) were ovariectomized (OV) and implanted with 17 $\beta$ estradiol (E) and/or progesterone (P), or placebo in three separate studies (phases) of 10 days each. Uterine weights (p =.0001) and radioimmunoassay confirmed hormonal bioactivity. The sham (S) group with placebo implant …

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John Guare: In Search Of America., Kenny Clifford Gannon Jan 1995

John Guare: In Search Of America., Kenny Clifford Gannon

LSU Historical Dissertations and Theses

This study examines the full scope of Guare's plays, from his Off-Off Broadway experimentation in the sixties through his 1992 play Four Baboons Adoring the Sun, and their place in America's cultural landscape. Set against the framework of modern cultural history, the investigation attempts to reveal Guare's vision of modern America's quest for fulfillment through the correlation of textual and stylistic analysis, critical response, and Guare's stated views. The study contends that Guare's portrayal of American desire unmasks the mass media's contamination of the American dream. From the very inception of his dramatic imagination, Guare has mixed fantasy and reality …

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Biochemical And Microbiological Characteristics Of Ground Beef In Modified Atmosphere Packaging With Gas Exchange., Chung-Ping Ho Jan 1995

Biochemical And Microbiological Characteristics Of Ground Beef In Modified Atmosphere Packaging With Gas Exchange., Chung-Ping Ho

LSU Historical Dissertations and Theses

The shelf-life of ground beef in modified atmosphere packaging (MAP) with exchange of gases before retail display was compared with conventional vacuum packaging (VP) and overwrapping with polyvinylchloride film (PVC) for display. Ground beef patties in MAP with distribution gases of 20% $\rm N\sb2:80\%\ CO\sb2,\ 50\%\ N\sb2:50\%\ CO\sb2,\ or\ 80\%\ N\sb2:20\%\ CO\sb2$ and display gases of 80% $\rm O\sb2:20\%\ CO\sb2,\ 50\%\ O\sb2:20\%\ CO\sb2:30\%\ N\sb2,$ or 20% $\rm O\sb2:20\%\ CO\sb2:60\%\ N\sb2$ had decreased weight loss, microorganism growth rate, metmyoglobin formation, and color degradation compared with patties in VP-PVC. Increased CO$\sb2$ during distribution retarded microbial growth. Display gas mixtures with higher O$\sb2$ …

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Biotic And Abiotic Factors That Affect The Development And Survival Of Cat Flea (Ctenocephalides Felis (Bouche)) Life Stages., William Joseph Lawrence Jr Jan 1995

Biotic And Abiotic Factors That Affect The Development And Survival Of Cat Flea (Ctenocephalides Felis (Bouche)) Life Stages., William Joseph Lawrence Jr

LSU Historical Dissertations and Theses

Biotic and abiotic factors that affect the development and survival of cat flea (Ctenocephalides felis (Bouche)) life stages were studied. Adult feas maintained on an artificial host system exhibited high rates of mortality when provided with dog hair substrates washed in either hexane or soap and water. Delayed egg production for fleas provided with bovine blood containing Na Citrate concentrations $>$8 mM was observed. Fleas fed with Na Citrate concentrations $\ge$24 mM had an increase in blood consumption and mortality. Certain concentrations of testosterone fed to fleas either in steer blood or in an alternate blood meal were associated …

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Follicular Development Patterns Of Pregnant Mares During The First Half Of Gestation., Marius Meintjes Jan 1995

Follicular Development Patterns Of Pregnant Mares During The First Half Of Gestation., Marius Meintjes

LSU Historical Dissertations and Theses

Information gained by studying follicular wave and endocrinological patterns of pregnant mares, may be useful in understanding reproductive wastage, infertility, control of the estrous cycle and physiological function of equine chorionic gonadotropin (eCG). Furthermore, supplementary follicular development, characteristic of the early equine pregnancy, may be used to harvest oocytes for gamete intrafallopian tube transfer and in vitro fertilization (IVF) procedures. The objectives of this study were to: characterize follicular wave patterns during the first half of the equine pregnancy; relate follicular development patterns to serum levels of estradiol-17$\beta$, progesterone, FSH and eCG; evaluate the effect of fetal genotype on follicular …

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Synthesis And Characterization Of Water Soluble Chitosan Derivatives., Javier Macossay Jan 1995

Synthesis And Characterization Of Water Soluble Chitosan Derivatives., Javier Macossay

LSU Historical Dissertations and Theses

Chitin, one of the most ubiquitous natural polymers, remains underutilized. The integral part chitin plays in natural biocomposites suggests that synthetic composites incorporating chitin should exhibit interesting properties, both with respect to strength and biodegradability. Due to a very strong hydrogen bonding, chitin is a very intractable material, but its derivative, chitosan, is very amenable to chemical modifications. Controlled deacetylation of chitin produces water soluble chitosan that is very efficient in complexing metals and natural biomolecules; major applications in water purification are reviewed. In an effort to produce more water soluble derivatives of chitosan, with potential applications in the cosmetics …

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Aqueous Processing Influences On Composition And Functionality Of Mechanically Separated Broiler Meat., Henri Khalil Salman Jan 1995

Aqueous Processing Influences On Composition And Functionality Of Mechanically Separated Broiler Meat., Henri Khalil Salman

LSU Historical Dissertations and Theses

The demand for breast meat has caused a surplus of broiler legquarters, which cannot be easily or efficiently deboned by hand. Oxidative stability and texture of mince recovered with two mechanical deboners, a belt/drum separator with 5 mm (BD5), 2 mm (BD2), and 5 mm followed by 2 mm (BD5/2) drum or auger/sieve (SD) deboner with slit openings of 0.25 mm, were evaluated. Mechanical deboned chicken meat (MDCM) had higher fat, ash and lower moisture than hand deboned meat. BD2 meat contained calcium at levels below those allowed by USDA, but had higher fat that decreased oxidative stability. Washing of …

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Interleukin-2 Promoter/Enhancer Controlled Expression Of A Synthetic Cecropin-Class Lytic Peptide In Transgenic Mice., William Andrew Reed Jan 1995

Interleukin-2 Promoter/Enhancer Controlled Expression Of A Synthetic Cecropin-Class Lytic Peptide In Transgenic Mice., William Andrew Reed

LSU Historical Dissertations and Theses

Pathogens continue to evolve mechanisms of avoiding efforts to control their spread. Treatment with exogenous antimicrobials often occurs after the pathogen has reproduced extensively in the host. In the case of mammals, the immune system may not be fully mobilized for 72 h after the detection of foreign antigen. However, within 24 h of presentation of antigen by antigen-presenting cells to resting thymus-derived lymphocytes IL2 is produced. A class of broad spectrum antimicrobial peptides which constitute a major component of the insect immune system has been described and characterized. Called "cecropins", they are relatively non-toxic to normal cells from multicellular …

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Binding Of Hepatic Nuclear Proteins From Obese And Lean Zucker Rats To The Upstream Region Of Malic Enzyme Gene., Yibing Wang Jan 1995

Binding Of Hepatic Nuclear Proteins From Obese And Lean Zucker Rats To The Upstream Region Of Malic Enzyme Gene., Yibing Wang

LSU Historical Dissertations and Theses

Adrenal glucocorticoids are essential for the development of all forms of experimental obesity. In the obese (fa/fa) Zucker rats, adrenalectomy prevents the further development of obesity, and glucocorticoid replacement restores the obese phenotype. We have hypothesized that this dependence on glucocorticoids is due to differences in transcriptional regulation of a group of genes that are normally regulated by glucocorticoids. We have chosen to study the DNA fragments from the upstream region of the malic enzyme (ME) gene, which is positively regulated by glucocorticoids. Hepatic nuclear extracts from lean and obese Zucker rats were used in band shift studies to look …

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Dietary Chromium Supplementation For Pigs And Chickens., Terry Lynn Ward Jan 1995

Dietary Chromium Supplementation For Pigs And Chickens., Terry Lynn Ward

LSU Historical Dissertations and Theses

Three experiments were conducted with pigs and four experiments were conducted with chickens to determine the effects of supplemental dietary Cr on growth performance, carcass characteristics, tissue minerals and plasma metabolite and hormone concentrations. In pigs (Exp. 1) 200 ppb Cr from seven different sources tended to decrease performance during the grower phase and increase growth performance during the finisher phase. Dietary Cr had minimal effects on plasma metabolite and hormone concentrations and Cr did not affect carcass characteristics. In general, dietary Cr increased tissue Cr concentration, except for longissimus muscle (LM). In Exp. 2, pigs were fed 400 ppb …

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In Vitro Maturation, In Vitro Fertilization And Development Of Bovine Oocytes., Li Zhang Jan 1995

In Vitro Maturation, In Vitro Fertilization And Development Of Bovine Oocytes., Li Zhang

LSU Historical Dissertations and Theses

To improve the efficiency of the culture system for bovine in vitro fertilization (IVF), several factors affecting the success of in vitro maturation (IVM), IVF and in vitro culture (IVC) of bovine oocytes were studied. A simple and efficient procedure has been developed for IVM/IVF/IVC of bovine follicular oocytes, which consistently produced 45 to 50% morulae and blastocysts during the treatment of over 6,000 oocytes. Ovary holding temperatures of $\rm 0\sp\circ C,\ 18\sp\circ C\ and\ 25\sp\circ C$ were found to affect the rate of maturation, fertilization and cleavage (P $<$ 0.05). When ovaries were held at 25$\sp\circ$C for 3 h, 20% of the oocytes developed to blastocysts and hatched in vitro, indicating that this temperature is suitable for holding ovaries during transportation. The highest cleavage rate (79%) was obtained when oocytes were matured and fertilized both at 39$\sp\circ$C in 5% CO$\sb2$. Fertilization rate was impaired with a lowered incubation temperature (37$\sp\circ$C) and CO$\sb2$ level (2.5%). Cumulus cells were shown to be important and necessary for IVM and acquisition of competence for full embryonic development. Cumulus cell removal before IVM, before IVF or 7 h after IVF reduced the rates of maturation, fertilization and development at all embryo stages evaluated (P $<$.05). Cumulus cell removal at 20 h after fertilization resulted in a rate of development similar to control embryos (P $>$.05). Co-culture enhanced the development of IVF-derived embryos. More embryos …

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The Life History (Age, Growth And Reproduction) Of Red Snapper (Lutjanus Campechanus) And Its Affinity For Oil And Gas Platforms., Jeffrey Howard Render Jan 1995

The Life History (Age, Growth And Reproduction) Of Red Snapper (Lutjanus Campechanus) And Its Affinity For Oil And Gas Platforms., Jeffrey Howard Render

LSU Historical Dissertations and Theses

The purpose of this dissertation was to describe the association of red snapper, Lutjanus campechanus, with oil and gas platform habitat in the northern Gulf of Mexico. Ages were estimated using transverse sections of sagittae. Annuli were validated to have formed yearly. Age estimates ranged from less than 1 to 54 years. Von Bertalanffy growth models were significantly different for males and females; females exhibited a faster initial growth rate but achieved a lesser maximum length than did males. The variability in age among individuals of a given length or weight class precluded formulation of age at size keys. Otolith …

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The Effects Of Creatine Supplementation On Total Work Output And Metabolism During High-Intensity Intermittent Exercise., Michael Cory Prevost Jan 1995

The Effects Of Creatine Supplementation On Total Work Output And Metabolism During High-Intensity Intermittent Exercise., Michael Cory Prevost

LSU Historical Dissertations and Theses

The effects of creatine supplementation on endurance and metabolism during high intensity intermittent exercise was examined using 18 males and females (age 19-26). The subjects were randomly divided into 2 groups (creatine and placebo) and the testing proceeded in two phases. During phase 1 both groups received a placebo. During phase 2 the placebo group again received a placebo, while the creatine group received creatine. Testing consisted of a several high intensity intermittent cycling protocols on a stationary cycle ergometer. Both groups performed all test bouts (in random order) in phase 1 and again in phase 2. Testing consisted of: …

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Daily Variations Of Lipogenic Activities In Japanese Quail (Coturnix Coturnix Japonica)., Bruce L. Tedford Jan 1995

Daily Variations Of Lipogenic Activities In Japanese Quail (Coturnix Coturnix Japonica)., Bruce L. Tedford

LSU Historical Dissertations and Theses

Studies were made in Japanese quail (Coturnix c. japonica) to determine if daily variations of plasma insulin and de novo lipogenesis exists and examine the roles of daily variations in lipogenic responsiveness to insulin and prolactin. A daily variation in plasma insulin levels exists in quail fed ad libitum, with photophase levels 4.6 times greater than scotophase levels. This variation was not driven exclusively by the feeding of the quail, because insulin levels had dropped by dark onset, yet all bird's crops contained food at this time. There was a daily variation in the amount of $\sp{14}$C-acetate labelled lipids extracted …

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Gulf Literacy: A Marine Science-Based Model Of Scientific Literacy., John Edward Trowbridge Jan 1995

Gulf Literacy: A Marine Science-Based Model Of Scientific Literacy., John Edward Trowbridge

LSU Historical Dissertations and Theses

A trend in science education reform is the move towards the goal of scientific literacy. Attributes of scientific literacy include: (a) understanding key concepts and principles of science; (b) understanding newspaper articles and graphics related to science issues; and (c) using scientific ways of evaluating evidence for individual and societal purposes (AAAS, 1989; Demastes & Wandersee, 1992). Furthermore, BSCS (1993) has proposed a model of biological literacy that includes four distinct levels (nominal, functional, structural, and multidimensional). The Gulf of Mexico and its coastal environments are of social, economic and scientific importance. An understanding of the Gulf of Mexico in …

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Diallel Analyses Of Percent Kernel Infection By Aspergillus Flavus And Ear Moisture Loss Rate In Maize., Yudong Zhang Jan 1995

Diallel Analyses Of Percent Kernel Infection By Aspergillus Flavus And Ear Moisture Loss Rate In Maize., Yudong Zhang

LSU Historical Dissertations and Theses

Preharvest infection by Aspergillus flavus Link ex Fries and subsequent aflatoxin contamination of maize (Zea mays L.) grain are major production problems. Ear moisture loss rate (EMLR) is an important component of hybrid performance and maturity, and to some extent determines the suitability of a hybrid for a geographical area. A 10-parent diallel experiment was conducted in 1992 and 1994 to study the genetic nature of both percent kernel infection (PKI) by A. flavus and EMLR. General combining ability (GCA, V$\sb{\rm g}$), specific combining ability (SCA, V$\rm\sb{s}$), and reciprocal mean squares for PKI were significant. The ratio $\rm 2V\sb{g}/(2V\sb{g}+V\sb{s}$) was …

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Effects Of Environmental Factor Gradients On Survival, Growth And Physiology Of Two Species Of Crab Within The Genus Callinectes., John Louis Guerin Jan 1995

Effects Of Environmental Factor Gradients On Survival, Growth And Physiology Of Two Species Of Crab Within The Genus Callinectes., John Louis Guerin

LSU Historical Dissertations and Theses

Effects of environmental factor gradients on growth, molting and physiology of crabs within the genus Callinectes were examined. Juvenile blue crabs, Callinectes sapidus, were exposed to a range of dissolved cadmium concentrations at two salinities (2.5 and 25$\perthous$). 21-day LC$\sb{50}$'s were lower at 2.5$\perthous$ (19 $\mu$g l$\sp{-1}$) than at 25$\perthous$ (186 $\mu$g l$\sp{-1}).$ Crabs were exposed to Cd levels of 0, 50 and 100 $\mu$g l$\sp{-1}$ for bioenergetic measurements. Energy expenditure did not vary with cadmium. Scope for growth, energy consumption and energy absorption were unaffected by Cd at 25$\perthous,$ but decreased with exposure to cadmium at 2.5$\perthous.$. Juvenile lesser …

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Data Analysis Using Reconstructability Theory., Deky Dicky Joe Gouw Jan 1995

Data Analysis Using Reconstructability Theory., Deky Dicky Joe Gouw

LSU Historical Dissertations and Theses

In this dissertation, we develop a new data analysis method using reconstructability theory, particularly k-systems theory. K-systems or Klir systems theory is a branch of reconstructability theory and provides a setting wherein common problems in statistics can be solved using the power of information theory by invoking the maximum entropy principle. The method is superior over classical statistical data analysis. The approach starts with the concept of variable interaction in reconstructability analysis (RA), We then use the RA definition of interaction to improve the quality of main and interaction effects in data analysis. With classical statistical data analysis, we need …

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Nitrogen Biogeochemistry Of Aquaculture Pond Sediments., John Albert Hargreaves Jan 1995

Nitrogen Biogeochemistry Of Aquaculture Pond Sediments., John Albert Hargreaves

LSU Historical Dissertations and Theses

Aquaculture pond water quality is dominated by planktonic processes, although the high surface-to-volume ratio suggests that sediment has the potential to effect important changes in water quality. The objectives of this research were to evaluate annual variation of sediment nitrogen biogeochemistry and develop a model of annual variation in ammonia concentration in a commercial channel catfish pond. In addition, the effects of physical and chemical sediment management techniques on water quality in aquatic mesocosms were evaluated. Sediment nitrogen was dominated by organic (92-96%) and adsorbed ammonium (2-4%) fractions. Porewater ammonium comprised the smallest yet most dynamic component of sediment N, …

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The Effect Of Developmental Factors On The Use Of An Electronic Communication Device., Judith Danute Oxley Jan 1995

The Effect Of Developmental Factors On The Use Of An Electronic Communication Device., Judith Danute Oxley

LSU Historical Dissertations and Theses

This study addressed a poorly understood variable of voice output communication aid (VOCA) use, namely mnemonic development. Forty children without disabilities, aged from 49 to 60 months, were required to use an IntroTalker (Prentke Romich Company) to participate in a one-on-one storybook reading task with the investigator. They were provided with sixteen messages to use during a scripted reading of The Three Bears. Children could use a trained verbal elaboration strategy or generate their own methods to retrieve messages. Immediate and delayed responses of children under two training methods were compared, and the contribution of developmental factors, including metamemory, were …

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Estimation Of Genetic Parameters For Preweaning Growth Traits Of Crossbred Cattle., Denis Jose Salgado-Fonseca Jan 1995

Estimation Of Genetic Parameters For Preweaning Growth Traits Of Crossbred Cattle., Denis Jose Salgado-Fonseca

LSU Historical Dissertations and Theses

Data from a long-term rotational crossbreeding study involving Angus, Brahman, Charolais and Hereford cattle were analyzed to evaluate the importance of maternal effects on birth weight (BWT), weaning weight (WWT) and preweaning average daily gain (ADG) and, to estimate genetic parameters. Six different animal models were fitted for each trait, ranging from a single additive to a maternal animal model allowing for both genetic and environmental maternal effects and a genetic covariance between direct and maternal additive effects. Genetic effects were obtained using a maternal animal model allowing for a maternal additive effect and a direct-maternal additive covariance (Model 4). …

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