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Systematics Of Rudbeckia Subgenera Macrocline And Laciniata (Asteraceae: Heliantheae: Rudbeckiinae)., Patricia Blackwell Cox Jan 1991

Systematics Of Rudbeckia Subgenera Macrocline And Laciniata (Asteraceae: Heliantheae: Rudbeckiinae)., Patricia Blackwell Cox

LSU Historical Dissertations and Theses

Rudbeckia, a North American genus, consists of approximately 21 species of annual and perennial herbs. Rudbeckia is separated into three subgenera (i.e. Laciniata (n = 19 (18)), Macrocline (n = 18) and Rudbeckia (n = 19)) based on morphological, cytological, chemical, and phylogenetic data. The present research includes a systematic study of subgenera Laciniata and Macrocline. Also included is a phylogenetic analysis of the coneflower genera (Dracopis, Echinacea, Ratibida, and Rudbeckia). Subgenus Laciniata contains Rudbeckia laciniata, which is composed of five morphological and geographical overlapping varieties. These include var. ampla, var. bipinnata, var. digitata, var. heterophylla, and var. laciniata. Twelve …

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Genetics Of Resistance To Preharvest Aflatoxin Accumulation In Maize Containing The Lfy Gene., Daniel Preston Gorman Jan 1991

Genetics Of Resistance To Preharvest Aflatoxin Accumulation In Maize Containing The Lfy Gene., Daniel Preston Gorman

LSU Historical Dissertations and Theses

Preharvest infection of maize (Zea mays L.) grain by Aspergillus flavus Link ex Fries and subsequent aflatoxin contamination is a serious problem, especially in the southeastern USA. Studies on the genetics of resistance to aflatoxin contamination in maize are quite limited, but a better understanding of this aspect is needed for developing resistant germplasm. The objective of the first field study was to determine the genetics of resistance to aflatoxin contamination in maize possessing the leafy (Lfy) gene. Seven Lfy synthetic genotypes were crossed in a diallel fashion, and the resulting 21 single crosses were evaluated for aflatoxin contamination in …

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Quantitation Of Phenolic Acids And Effect Of Controlled Atmosphere Storage On Peach Fruit Quality., Ahmed Fathallah El-Shiekh Jan 1991

Quantitation Of Phenolic Acids And Effect Of Controlled Atmosphere Storage On Peach Fruit Quality., Ahmed Fathallah El-Shiekh

LSU Historical Dissertations and Theses

Total and individual phenolic acids in firm-ripe fruit of ten different peach (Prunus persica Batsch.) genotypes were analyzed by spectrophotometry and high performance liquid schrmoatography (HPLC) and related to internal browning potential. A comparison of phenolic acid separation was made between five different column types. A Lichrosorb RP-18 column provided the best separation of the major phenolic acids in peach fruit mesocarp tissue. Quinic was the predominant phenolic acid, followed in concentration by gentisic, catechin, chlorogenic, and syringic acids. Quantities differed between genotypes. The genotypes with the highest internal browning potential contained the highest concentration of chlorogenic acid, gentisic acid, …

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Stereoelectronics Of Carboxylate-Imidazolium Hydrogen Bonds In Models Of The Aspartate-Histidine Couple In Serine Proteases., Nabeel Abdel Raouf Nabulsi Jan 1991

Stereoelectronics Of Carboxylate-Imidazolium Hydrogen Bonds In Models Of The Aspartate-Histidine Couple In Serine Proteases., Nabeel Abdel Raouf Nabulsi

LSU Historical Dissertations and Theses

The geometry of the carboxylate-imidazolium hydrogen bond in the crystalline state and the effect of microenvironment are investigated in models of the aspartate-histidine (Asp-His) couple. Synthetic methods leading to the preparation of intramolecular models, possessing syn and anti-oriented hydrogen bonds, also are described. A single-pot procedure has been developed for converting phenoxyacetonitriles into their respective benzimidazole derivative in higher yields than the traditional two step procedure. An efficient single-pot procedure also has been developed for converting benzofuran to its acetylene derivative, 2-acetoxyphenylacetylene. This method involves in situ acetylation of the unstable phenol intermediate. Nine intermolecular imidazolium-benzoate couples have been prepared …

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A Study Of The Metal Clusters In The Nitrogenase Proteins Of Azotobacter Vinelandii., Melinda Ehrlich Oliver Jan 1991

A Study Of The Metal Clusters In The Nitrogenase Proteins Of Azotobacter Vinelandii., Melinda Ehrlich Oliver

LSU Historical Dissertations and Theses

Electron Paramagnetic Resonance (EPR) spectroscopy was used to examine the paramagnetism of the clusters in nitrogenase from Azotobacter vinelandii. The EPR spectrum of nitrogenase (Av1 and Av2) was examined in the presence of an extrinsic paramagnet, DyEDTA, at different concentrations of NaCl, during thionine oxidation (Av1), and in the presence of MgATP (Av2). Cross combinations of Av1 and Av2 were also investigated in the presence and absence of the chemical cross-linker, EDC as well as with the nitrogenase components from Clostridium pasteurianum. From relaxation enhancement measurements, the distance of closest approach of DyEDTA to the intrinsic metal clusters in Av1 …

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Isolation And Characterization Of Macrophage Inhibitory Compounds From Mycobacterium Paratuberculosis., Murray Elison Hines Ii Jan 1991

Isolation And Characterization Of Macrophage Inhibitory Compounds From Mycobacterium Paratuberculosis., Murray Elison Hines Ii

LSU Historical Dissertations and Theses

Fractions exhibiting activity detrimental to the killing function of activated bovine monocyte/macrophages towards Candida albicans were obtained from Mycobacterium paratuberculosis. Active fractions were initially derived by ultrasonication of bacterial samples followed by ammonium sulfate precipitation, ion-exchange chromatography, gel filtration chromatography, heat precipitation, acid precipitation and alkali treatment. Two different fractions that exhibited marked inhibition of macrophage killing ability were derived and partially characterized. Novel methodology was developed to accomplish the task of lysis and fractionation of mycobacteria utilizing the Matrix Solid Phase Dispersion (MSPD) technique that appeared to be much more efficient and is certainly less time consuming and less …

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Comparative Inflorescence And Floral Development In The Asteraceae. (Volumes I And Ii)., Elizabeth M. Harris Jan 1991

Comparative Inflorescence And Floral Development In The Asteraceae. (Volumes I And Ii)., Elizabeth M. Harris

LSU Historical Dissertations and Theses

Floral and inflorescence development of 39 species of Asteraceae and four additional species representing possible outgroups were examined with the scanning electron microscope (SEM). Taxon choice was designed to include representatives of 12 of the 12 to 18 tribes recognized in the large, morphologically diverse family. Although floral ontogeny has provided phylogenetically useful characters in other plant groups, no similar studies have been applied to solve phylogenetic problems in the Asteraceae. The necessary live material was collected in several ways: from natural populations throughout North America, from the worldwide collections of several botanical gardens, grown from seed, or from cultivated …

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Environmental Factors And Production Characteristics Affecting The Culture Of Red Drum, Sciaenops Ocellatus., Rowland Glenn Thomas Jan 1991

Environmental Factors And Production Characteristics Affecting The Culture Of Red Drum, Sciaenops Ocellatus., Rowland Glenn Thomas

LSU Historical Dissertations and Theses

Experiments with red drum, Sciaenops ocellatus, were conducted to assess environmental requirements and culture characteristics. Pond trials were used to evaluate the effects of salinity, chloride source, predator control, acclimation procedure, stocking density, and size at stocking on production. Survival in individual ponds ranged from 0-92%; average daily weight gain from 0.46-2.22g; and feed conversion ratio from 2.30-4.90. Survival, growth, and feed conversion ratio did not differ significantly between equivalent treatments in saltwater and freshwater ponds. The minimum chloride concentration necessary for acceptable production of red drum in freshwater ponds (250-300 mg/l) was at least 100% higher than the concentrations …

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A Study Of The Effects Of Prediction Activities On Instructional Outcomes In High School Genetics., Anne Spratlan Sinclair Jan 1991

A Study Of The Effects Of Prediction Activities On Instructional Outcomes In High School Genetics., Anne Spratlan Sinclair

LSU Historical Dissertations and Theses

The purpose of this study was to examine the instructional effects of incorporating prediction activities in a high school biology genetics curriculum. Criteria for instructional effectiveness included enhanced levels of classroom discussion and interaction, improved subject-related attitude, higher achievement motivation, and greater mastery of genetics concepts. Genetics was chosen as the domain of research because of the multiple variables operating which make it amenable to the making of predictions. Four experienced high school biology teachers taught an experimental and a control class. Students in the experimental classes made written predictions using researcher-developed prediction activities as an introduction to 19 genetics …

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An Ethnographic Study Of Kindergarten Children's Literacy Skills And Stress-Related Behaviors Before And After Teacher Demonstration., Nancy Crossland Weems Jan 1991

An Ethnographic Study Of Kindergarten Children's Literacy Skills And Stress-Related Behaviors Before And After Teacher Demonstration., Nancy Crossland Weems

LSU Historical Dissertations and Theses

The purpose of this ethnographic research was to study kindergarten students' literacy skills and stress-related behaviors and a teacher's instructional behavior before and after demonstrations in appropriate bookreading strategies. A lower socio-economic setting, which previously had been identified by Burts, Hart, Charlesworth, and Kirk (1990a) as a developmentally inappropriate instructional environment, was selected for observation as one which might be amenable to change. The demonstrations included bookreading strategies that the kindergarten teacher could implement to promote the acquisition of literacy in ways that do not contribute to stress. Ethnographic data collection consisted of three months of participant observation in one …

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The Frost Tolerance Of Tobacco Plants Transformed With The Gene Encoding The Antifreeze Protein From Winter Flounder., Jung-Sook Lee Jan 1991

The Frost Tolerance Of Tobacco Plants Transformed With The Gene Encoding The Antifreeze Protein From Winter Flounder., Jung-Sook Lee

LSU Historical Dissertations and Theses

The winter flounder, Pseudopleuronectes americanus, can survive in sea water at temperatures below freezing by producing antifreeze-proteins (AFPs) which depress the freezing point of their cellular fluids. The antifreeze gene (IIA7 cDNA) encodes a 91 amino acid preproprotein which is processed to a mature protein of 53 amino acids. This gene encoding only the mature antifreeze-protein, including a start methionine, was cloned into a plasmid which allowed enhanced expression from a double CaMV 35S promoter. The AFP gene construct was subcloned into both the intermediate vector pMON200 and the binary vector pBI121. After triparental mating and infection of tobacco leaf …

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Nuclear Transplantation: Intracellular Release And Extracellular Influx Of Calcium In Response To Electrofusion Pulse And Its Effect On Murine Oocyte Activation And Embryonic Development., Lee F. Rickords Jan 1991

Nuclear Transplantation: Intracellular Release And Extracellular Influx Of Calcium In Response To Electrofusion Pulse And Its Effect On Murine Oocyte Activation And Embryonic Development., Lee F. Rickords

LSU Historical Dissertations and Theses

The transplantation of early embryonic cell nuclei into oocytes in which the maternal chromosomes have been removed is a method by which multiple offspring of the same genotype can be produced. One critical factor required for successful development of nuclear transfer derived embryos is inducing the release of the recipient ooplasm from meiotic arrest (activation). This is accomplished during fusion of the two cells. The DC electrofusion pulse used to fuse the two cells together also activates the recipient ooplasm to resume meiotic events, however, the efficiency of electrofusion pulse induced activation remains low. It is known that activation of …

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The Differential Effects Of Either X-Irradiation Or Thermal Stress On The Two Major Cell Types Of The Blastocyst Stage Murine Embryo., Joe Steve Capehart Jan 1991

The Differential Effects Of Either X-Irradiation Or Thermal Stress On The Two Major Cell Types Of The Blastocyst Stage Murine Embryo., Joe Steve Capehart

LSU Historical Dissertations and Theses

The first objective of this investigation was to determine if either X-irradiation or thermal stress exerted differential effects on the two major cell types of the blastocyst stage murine embryo. Results of this study indicate that X-irradiation dosages of 0 rads, 500 rads, 600 rads, 700 rads, 800 rads, 900 rads or 1000 rads had no effect on the ability of treated embryos to either hatch or develop into trophoblastic outgrowths (P $<$.05). In contrast, X-irradiation treatment over the levels tested did have a detrimental effect on the ability of embryos to develop into trophblastic outgrowths possessing an ICM region (P $>$.05). X-irradiation over the levels tested had no effect on the mean two-dimensional outgrowth surface areas ($\mu$m$\sp2$) (P $>$.05). However, X-irradiation was found to have a …

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Study On Two Chitin-Binding Proteins From Vibrio Parahaemolyticus., Otto Silva Gildemeister Jan 1991

Study On Two Chitin-Binding Proteins From Vibrio Parahaemolyticus., Otto Silva Gildemeister

LSU Historical Dissertations and Theses

Two chitin-binding proteins from Vibrio parahaemolyticus are secreted into the culture medium after the addition of chitin or oligomers of N-acetylglucosamine, but only to lower levels of expression with a few other saccharides. The first protein exhibited a very salt-resistant chitinase activity with activity maxima at pH 6 and 9. The enzyme is stable for 30 minutes at 40$\sp\circ$C, and maximal activity is reached at 50$\sp\circ$C. The chitinase hydrolyzes optimally chitin oligomer substrates with degree of polymerization of 4 and higher. The hydrolytic activity upon the chitotrimer is low; the dimer cannot be hydrolyzed by the enzyme. When incubated with …

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The Evaluation And Comparison Of Aquatic Methodology For Measurement Of Bacterial Population Dynamics And Grazing Activity In Diverse Aquatic Ecosystems., Richardus F. Kaswadji Jan 1991

The Evaluation And Comparison Of Aquatic Methodology For Measurement Of Bacterial Population Dynamics And Grazing Activity In Diverse Aquatic Ecosystems., Richardus F. Kaswadji

LSU Historical Dissertations and Theses

Observations and experiments were conducted to evaluate methodologies for measuring aquatic bacterial population dynamics and grazing activity in ecologically dissimilar ecosystems. Samples were taken from Auke Bay, AK, the Mississippi River at Plaquemine, LA, the Terrebonne Bay estuary, LA, and the Mississippi River plume. Four methods were compared for measuring bacterioplankton growth and grazing mortality rates: dilution, filtration, antibiotic, and the Servais et al. (1985) procedures. The dilution method appeared to be the best among those compared. Among all sites, bacterial density ranged from 0.02 to 10$\sp6$ ml$\sp{-1}$, and bacterial growth and grazing mortality rates, estimated using the dilution method, …

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Functional Morphology Of Gustatory Centers In The Brain Of The Channel Catfish, Ictalurus Punctatus., Charles Franklin Lamb Iv Jan 1991

Functional Morphology Of Gustatory Centers In The Brain Of The Channel Catfish, Ictalurus Punctatus., Charles Franklin Lamb Iv

LSU Historical Dissertations and Theses

Gustatory nuclei in the isthmic region of the metencephalon and in the posterior diencephalon of the channel catfish, Ictalurus punctatus, were examined anatomically and electrophysiologically. Neurons in the superior secondary gustatory nucleus (nGS) responded to taste and tactile stimulation of large peripheral receptive fields (RFs) that often included the epithelia of the oropharyngeal cavity and whole extraoral body surface. Taste responses to amino acids and nucleotides were dose-dependent, with detected thresholds from micromolar to millimolar concentrations. The RF organization within the nGS did not display the somatotopy present in the medullary gustatory nuclei. Anatomical labeling of secondary gustatory fibers showed …

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The Structural Organization Of Photosystem Ii Polypeptides., William Robert Odom Jan 1991

The Structural Organization Of Photosystem Ii Polypeptides., William Robert Odom

LSU Historical Dissertations and Theses

The structural organization of Photosystem II polypeptides has been investigated using the protein crosslinking reagent 1-ethyl-3-(dimethyl-aminopropyl)-carbodiimide (EDC), and a library of mono- and polyclonal antibodies. The first phase of this research was to generate the antibody probes against specific PS II polypeptides. A murine monoclonal antibody, FQC3, was characterized. It recognized the D2 protein of Spinacia oleracea L. The second phase of this research utilized antibodies against D1, D2, CPa-1, CPa-2, Cyt b$\sb{559}$, 33 kDa manganese stabilizing protein (MSP), 24 kDa extrinsic protein, and the 17 kDa extrinsic protein to identify PS II subunits crosslinked by EDC. Several intra-complex crosslinked …

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Chromium, Tryptophan, And Picolinate In Diets For Pigs And Poultry., Timothy Guinn Page Jan 1991

Chromium, Tryptophan, And Picolinate In Diets For Pigs And Poultry., Timothy Guinn Page

LSU Historical Dissertations and Theses

Six experiments were conducted to evaluate the effects of supplemental dietary tryptophan (TRP), picolinate (Pic), CrCl$\sb3\cdot$6H$\sb2$O, chromium picolinate (CrPic), or a combination of Pic and CrCl$\sb3\cdot$6H$\sb2$O on growth performance, liver mineral concentrations, insulin, growth hormone, organ weights, and serum and carcass traits of pigs. One experiment was conducted to evaluate the effect of chromium picolinate (CrPic) on serum cholesterol (CH), egg CH, egg quality, and egg production of laying hens. Dietary TRP, Pic, CrCl$\sb3\cdot$6H$\sb2$O, and a combination of Pic and CrCl$\sb3\cdot$6H$\sb2$O did not affect growth performance, liver mineral concentrations, insulin, growth hormone, and serum and carcass traits of pigs. The …

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Factors Controlling The Distribution Of The Black Mangrove, Avicennia Germinans L., In A Louisiana Mangal/Salt Marsh Community., Charles Stuart Patterson Jan 1991

Factors Controlling The Distribution Of The Black Mangrove, Avicennia Germinans L., In A Louisiana Mangal/Salt Marsh Community., Charles Stuart Patterson

LSU Historical Dissertations and Theses

Mangroves are intertidal, halophytic trees limited to the tropics and subtropics because they are not cold-tolerant. In coastal Louisiana (29$\sp\circ$ N latitude), the black mangrove, Avicennia germinans, is the only mangrove found because Avicennia is the most cold-tolerant of mangrove genera. Avicennia intergrades with salt marsh cordgrass, Spartina alterniflora, with 3 observed zones: an Avicennia zone, a transition zone, containing both Avicennia and Spartina, and a Spartina zone. The purpose of this dissertation was to determine why A. germinans does not occur in the Spartina zone within a mangal/salt marsh ecotone. Three studies investigated the following zone differences in: (1) …

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The Alkaloids Of Erythrina: Clonal Evaluation And Metabolic Fate., Lori Denise Payne Jan 1991

The Alkaloids Of Erythrina: Clonal Evaluation And Metabolic Fate., Lori Denise Payne

LSU Historical Dissertations and Theses

The foliage of thirteen genetic clones of the nitrogen-fixing trees Erythrina berteroana, E. poeppigiana and E. costarricensis growing under similar environmental conditions in the Latin American Nitrogen Fixing Tree Arboretum, CATIE, Turrialba, Costa Rica, was evaluated by gas chromatography/mass spectrometry for toxic alkaloid content. The major alkaloid identified was $\beta$-erythroidine, a naturally derived drug used in the 1950s and 1960s as a neuromuscular blocking agent in surgery and electroshock treatments. Other alkaloids identified were $\alpha$-erythroidine, erybidine, erythraline, erysodine, oxo-$\beta$-erythroidine and several previously undescribed compounds. There was a difference of more than two orders of magnitude in the $\beta$-erythroidine concentration between …

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Examination Of Potato Virus X Subgenomic Rnas: Their Number, Their Coding Properties, And Their Possible Encapsidation., Mary A. Price Jan 1991

Examination Of Potato Virus X Subgenomic Rnas: Their Number, Their Coding Properties, And Their Possible Encapsidation., Mary A. Price

LSU Historical Dissertations and Theses

Potato Virus X is the type member of the Potexvirus group. It is a flexuous rod containing a single-stranded, positive-sense RNA. Previous studies have shown that during infection Potato Virus X synthesizes subgenomic RNAs to express internal cistrons. These studies demonstrated that six subgenomic RNAs could be detected in total RNA extracts from PVX-infected tissue; however, only four internal ORFs are predicted within the genomic RNA. Furthermore, two particle size populations were detected, one containing genomic RNA and one containing the coat protein mRNA. In the present investigation experiments were designed to examine PVX-encoded subgenomic RNAs with regard to their …

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Effects Of Propiconazole On Morphology, Development, And Epidemiology Of Rhizoctonia Solani, Causal Agent Of Rice Sheath Blight., Elly M. Van Eeckhout Jan 1991

Effects Of Propiconazole On Morphology, Development, And Epidemiology Of Rhizoctonia Solani, Causal Agent Of Rice Sheath Blight., Elly M. Van Eeckhout

LSU Historical Dissertations and Theses

Propiconazole was inhibitory to mycelial growth of Rhizoctonia solani in vitro. Sclerotial weight per colony was also reduced by propiconazole treatment but, in relation to total amount of mycelium, sclerotia formed earlier in 1 to 10 $\mu$g/ml plates than in control plates. Colony diameters from germinating sclerotia obtained from cultures growing at 0.5 to 10 $\mu$g/ml, were significantly greater than those of control colonies. Prolonged inhibitor activity resulted in increased branching, swollen or strongly tapered hyphal tips, formation of 'beaded' hyphae, and rupturing of hyphal walls when intrahyphal hyphae emerged. Abnormal fluorescent patches, representative of abnormal cell wall deposition, were …

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Structure Of Synthetic Oligosaccharides By Tandem Mass Spectrometry., Eunsun Yoo Yoon Jan 1991

Structure Of Synthetic Oligosaccharides By Tandem Mass Spectrometry., Eunsun Yoo Yoon

LSU Historical Dissertations and Theses

Certain linkage positions in oligosaccharides can be discerned by collision-activated dissociation mass spectrometry (MS-CID-MS), rationalized by molecular modeling. The first part of this dissertation shows that linkage-specific daughter ion spectra of synthetic amino-sugar containing oligosaccharides can be obtained from several alkylated derivatives such as sodiated, potassiated, ammoniated and lithiated derivatives. Methylated derivatives of the synthetic oligosaccharides give more useful linkage discernment product-ions, including a 3-linkage specific ion. A novel approach of relating daughter ion to parent ion ratios and collision energy is described and is predictive of linkage position in the first set of six oligosaccharides used. In the second …

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A Study Of Metacognitive Skill As Influenced By Expressive Writing In College Introductory Algebra Classes., Naomi Barbara R Allen Jan 1991

A Study Of Metacognitive Skill As Influenced By Expressive Writing In College Introductory Algebra Classes., Naomi Barbara R Allen

LSU Historical Dissertations and Theses

The quality of mathematics education has become a major concern to mathematics educators. As a result, increased attention is being given to identifying the abilities that underlie competent performance. An outcome of this effort is an increasing belief that the development of metacognitive skills is an essential component of proficient mathematics performance. Writing, because it promotes reflective thinking, is believed to be the vehicle for this development. Writing in the mathematics classroom has previously received anecdotal support for its benefits to the learner and to the instructor, and limited quantitative benefits in problem-solving ability toward mathematics. This study examined the …

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Timed Daily Thermopulses Alter The Circadian Hormonal Regulation Of Glucose And Lipid Metabolism., Christopher Joseph De Souza Jan 1991

Timed Daily Thermopulses Alter The Circadian Hormonal Regulation Of Glucose And Lipid Metabolism., Christopher Joseph De Souza

LSU Historical Dissertations and Theses

Studies were made in Syrian hamsters and Holtzman rats to examine roles for circadian rhythms in the control of body fats stores. Baseline and circadian rhythms of plasma insulin varied seasonally in the Syrian hamster. Baseline concentrations of the hormone were almost 4 times greater in scotosensitive female hamsters held on short daily photoperiods when they were fat than in lean animals at other seasons and other photoperiodic schedules. Additionally, plasma insulin levels in fat hamsters, but not in lean animals, peaked at light onset when lipogenic responsiveness to insulin is greatest. The circadian rhythms of plasma insulin are not …

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Partial Sequence And Characterization Of A Growth Hormone Gene Of The Red Drum (Sciaenops Ocellatus)., Carol Marie Dorworth Jan 1991

Partial Sequence And Characterization Of A Growth Hormone Gene Of The Red Drum (Sciaenops Ocellatus)., Carol Marie Dorworth

LSU Historical Dissertations and Theses

A growth hormone (GH) gene was isolated from nuclear DNA of the red drum (Sciaenops ocellatus). Synthetic oligonucleotides were synthesized based on published cDNA sequences of other perciform fishes. Polymerase chain reaction (PCR) methodology was employed to amplify a nucleotide sequence extending from the 5$\sp\prime$ end of intron I to 15 bases upstream of the 3$\sp\prime$ end of exon VI of the GH gene. Amplified DNA was cloned into a phagemid sequencing vector. Clones were sequenced. Computer analysis of sequence data was used to determine the internal gene arrangement of exons and introns. Homologies of the nucleotide and deduced amino …

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Oxidative Chemical Transformations Of Sesquiterpene Lactones., Howard Gordon Pentes Jan 1991

Oxidative Chemical Transformations Of Sesquiterpene Lactones., Howard Gordon Pentes

LSU Historical Dissertations and Theses

Oxidative chemical transformations of sesquiterpene lactones have been carried out to determine the effect these changes have on the biological activities of these derivatives. Vacuum liquid chromatography was used extensively to isolate the sesquiterpene lactones used for these synthetic transformations. Costunolide and dehydrocostuslactone were isolated from Costus Resinoid (Saussurea lappa) and dihydroparthenolide was isolated from Ambrosia artemisiifolia. The enolate oxidations of sesquiterpene lactones with oxygen and (camphorylsulfonyl)oxaziridine have been investigate. Enolate oxidations of sesquiterpene lactones with oxygen generate low yields of both 11$\alpha$- and 11$\beta$-hydroxylactones. The yields of enolate oxidations with (camphorylsulfonyl)oxaziridine are much improved (over oxygen) and the reaction …

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Acoustic Topology Of Infant Proto-Syllables., James Robert Piroli Jan 1991

Acoustic Topology Of Infant Proto-Syllables., James Robert Piroli

LSU Historical Dissertations and Theses

A corpus of CV-like proto-syllables was obtained from the archival recordings of three first-born infants, which were made in conjunction with earlier research on the acoustic and interactive aspects of infant language acquisition. Tokens were limited to proto-syllables with perceptual evidence of stop-like or glide-like qualities and an identifiable vowel. Following A/D sampling, measures of developmental change were made including F1/F2 steady states, transition durations, CV durations, maximum F2 velocities, F2 onset, fundamental frequency, shimmer, time-to-peak amplitude velocity, and time-to-peak F2 velocity within the transition. Contrary to expectations, the orderliness of the infant protosyllables was remarkable with few acoustic events …

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Metabolism And Mutagenicity Of Dinitropyrenes: Effect Of Chronic Ethanol Ingestion And Aroclor 1254 Pretreatment., Antal Karl Hajos Jan 1991

Metabolism And Mutagenicity Of Dinitropyrenes: Effect Of Chronic Ethanol Ingestion And Aroclor 1254 Pretreatment., Antal Karl Hajos

LSU Historical Dissertations and Theses

The nitroreduction of three potently mutagenic dinitropyrene (DNP) isomers by liver cytosol from Aroclor-1254-pretreated rats was studied. NAD(P)H-quinone oxidoreductase (NQOR) is increased 12- to 24-fold by this treatment and resulted in up to 5-fold induction of cytosolic DNP-nitroreductase as compared to chow-fed controls. Upon purification, NQOR activity towards menadione coeluted with C-nitroso- and 1,6-DNP nitroreductase activity. Purified NQOR catalyzed NAD(P)H-dependent reduction of all DNP, displayed the same isomer specificity as did cytosol and increased the mutagenicity of all DNP in the Ames assay up to 3-fold. In TA98NR, a strain deficient in nitroreductase, only the mutagenicity of 1,3-DNP was markedly …

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Pcr Amplification Of Chlamydial Momp Genes: Detection, Sequence Analysis And Evolution., Bernhard Kaltenboeck Jan 1991

Pcr Amplification Of Chlamydial Momp Genes: Detection, Sequence Analysis And Evolution., Bernhard Kaltenboeck

LSU Historical Dissertations and Theses

Sensitive detection and differentiation of the bacterial genus Chlamydia (C.) was accomplished using the polymerase chain reaction (PCR), and phylogenetic relationships among chlamydiae were inferred from DNA sequences of amplified major outer membrane protein (MOMP) genes. DNA of strains of C. psittaci was efficiently amplified using primers homologous to nontranslated regions of the MOMP genes (ompA). Portions of these reactions were reamplified using one different primer specific for an internal ompA sequence. Primary amplification products were differentiated by restriction analysis. Degenerate, inosine containing oligonucleotide primers homologous to terminal translated regions amplified DNA fragments of all chlamydial MOMP genes. Partial ompA …

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