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Applications Of Solid State Deuterium Nmr Spectroscopy To Organotransition Metal Complexes., Maria Ines Altbach Jan 1988

Applications Of Solid State Deuterium Nmr Spectroscopy To Organotransition Metal Complexes., Maria Ines Altbach

LSU Historical Dissertations and Theses

Solid-state deuterium NMR spectroscopy has been applied to several organometallic complexes. The deuterium quadrupole coupling constants for cis-($\mu$-C$\sp{\rm 2}$H$\sb{\rm 2}$)($\mu$-CO) (FeCp$\sp{\rm d=5}$(CO)$\rbrack\sb{\rm 2}$ (Cp$\sp{\rm d=5}$ = 5% deuteriated cyclopentadienyl), trans-($\mu$-C$\sp{\rm 2}$H$\sb{\rm 2}$) (MnCp$\sp{\rm d=2.7}$(CO)$\sb{\rm 2}$) $\sb{\rm 2}$ (Cp$\sp{\rm d=2.7}$ = 2.7% deuteriated cyclopentadienyl), and trans-($\mu$-C$\sp{\rm 2}$H$\sb{\rm 2}$ (CoCp$\sp{\rm d=5}$(CO)) $\sb{\rm 2}$ were determined by conventional solid-state deuterium NMR spectroscopy. The charges on the methylene bridging site for the three bridging methylene metal dimers were calculated by modeling the difference in deuterium quadrupole coupling constant between the sample and the reference molecule, (9,9-$\sp{\rm 2}$H$\sb{\rm 2}$)fluorene, by the change in occupancy of …

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The Relationship Between Root Anatomic And Metabolic Responses To Soil Waterlogging In The Coastal Grass Spartina Patens., David Maaloe Burdick Jan 1988

The Relationship Between Root Anatomic And Metabolic Responses To Soil Waterlogging In The Coastal Grass Spartina Patens., David Maaloe Burdick

LSU Historical Dissertations and Theses

Spartina patens is a perennial grass that dominates dune, swale and marsh habitats in coastal Louisiana. Plant roots require oxygen for respiration and normal root function, and one of the most serious problems wetland plants encounter is the development of anaerobic conditions in the soil. The remarkable success of S. patens in habitats that occupy distant positions on a soil waterlogging gradient suggests either genetic differentiation or phenotypic adaptation among these populations. Field and greenhouse investigations were conducted to: (1) identify anatomic and metabolic soil waterlogging responses in Spartina patens, (2) examine the relationship between these responses, and finally (3) …

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An Initial Identification Of Parasite Specific Immune Responses In The Jird (Meriones Unguiculatus) Infected With Brugia Pahangi., Rita Gaskin Farrar Jan 1988

An Initial Identification Of Parasite Specific Immune Responses In The Jird (Meriones Unguiculatus) Infected With Brugia Pahangi., Rita Gaskin Farrar

LSU Historical Dissertations and Theses

Brugia pahangi infections in the jird (Meriones unguiculatus) is an accepted experimental model for the study of human lymphatic filariasis. Initial identification of parasite specific immune responses in jirds infected with B. pahangi are reported here. Antibody reactivity in sera from singly and multiply infected jirds against different stages of B. pahangi was determined using an indirect fluorescent antibody technique. All life cycle stages of the parasite were examined. Antibodies recognizing all stages were present in all serum samples. Removal of antibody reactivity by absorption of jird sera with B. pahangi antigen coated beads indicated that the antibodies were parasite …

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Crystal Structure Analyses Of An Organic Charge Transfer Salt, Three Bridged Binuclear Cobalt Complexes, And A Thiazole Derivative., Andrea Claire Greene Jan 1988

Crystal Structure Analyses Of An Organic Charge Transfer Salt, Three Bridged Binuclear Cobalt Complexes, And A Thiazole Derivative., Andrea Claire Greene

LSU Historical Dissertations and Theses

The structures of five compounds have been determined by single crystal x-ray diffraction. A non-superconducting organic charge-transfer salt, bis- (bis-(ethylenedithia)-tetrathiafulvalene) dibromoaurate(I), (BEDT-TTF)$\sb2$AuBr$\sb2$, was synthesized electrochemically, and crystallizes in monoclinic space group P2/c with Z = 2 and lattice constants 9 = 7.7950(21) A, b = 6.7150(6) A, c = 32.2000(31) A, $\beta$ = 100.508(13)$\sp\circ$; R = 0.0365 for 174 variables and 1904 observed reflections. One end of the independent BEDT-TTF molecule is disordered, a crystallographic feature which is common in these salts. Short sulfur-sulfur contact distances between cations are observed; however, the cations are not arranged in the same manner …

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Search For Allelochemicals In Rice (Oryza Sativa L.) And Structure Determination Of External Flavonoids Of Calamintha Ashei., Hidelisa Padua Hernandez Jan 1988

Search For Allelochemicals In Rice (Oryza Sativa L.) And Structure Determination Of External Flavonoids Of Calamintha Ashei., Hidelisa Padua Hernandez

LSU Historical Dissertations and Theses

The first part of this work was conducted to search for allelochemicals from the rice varieties PI346833 (moderately resistant) and Mars (susceptible) that may be responsible for resistance to fall armyworm, Spodoptera frugiperda (J. E. Smith) feeding. Mature tillers and seedlings were extracted with petroleum ether (PE), dichloromethane (DCM), acetone, methanol and water. The search for biological activity towards fall armyworm (FAW) was directed by growth inhibition bioassay. Significant antibiotic activity to FAW was observed with the PE and DCM crude extracts. Bioassay of the fractions of the PE and DCM extracts indicated that the fractions from PI346833 seedlings adversely …

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A Study Of The Interaction Of Peroxidic Tumor Promoters With Mitochondria., Christopher Henry Kennedy Jan 1988

A Study Of The Interaction Of Peroxidic Tumor Promoters With Mitochondria., Christopher Henry Kennedy

LSU Historical Dissertations and Theses

When micromolar concentrations of benzoyl peroxide (BPO) are added to rat liver mitochondria, inhibition of mitochondrial NADH-oxidase and succinoxidase is observed. The addition of a classical uncoupler of oxidative phosphorylation results in only partial release of this inhibition, suggesting that BPO inhibits both electron- and energy-transfer in mitochondria. Difference spectroscopy and artificial electron donor results indicate that BPO interacts at coupling site II between cytochromes b and c$\sb1$. BPO only yields radicals in mitochondria via inhibition of electron transport, which results in the formation of superoxide radicals. BPO also induces rapid, large-amplitude swelling of mitochondria; the swelling is dependent on …

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Synthesis, Transport And Assembly Of Wild Type And Mutant Precursors Of The Small Subunit Of The Chloroplast Enzyme Ribulose-1,5-Bisphosphate Carboxylase/Oxygenase., Samuel John Landry Jan 1988

Synthesis, Transport And Assembly Of Wild Type And Mutant Precursors Of The Small Subunit Of The Chloroplast Enzyme Ribulose-1,5-Bisphosphate Carboxylase/Oxygenase., Samuel John Landry

LSU Historical Dissertations and Theses

The small subunits of the chloroplast enzyme ribulose-1,5-bisphosphate carboxylase/oxygenase (RuBisCO) are synthesized in the cytoplasm as precursors and transported into the organelle. The precursor (pS) of the small subunit (S) of RuBisCO contains an amino-terminal extension, the transit peptide, which is removed during or after transport into the chloroplast. The possible involvement of an RNA-containing component in transport of proteins into chloroplasts was investigated using a reconstituted system of pS translated in vitro and isolated chloroplasts. The post-ribosomal supernatant of the in vitro translation mixture and/or isolated chloroplasts were treated with ribonuclease prior to incubation for transport. Transport of pS …

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The Combustion Of Carbon-Tetrachloride In A High Temperature Methane-Air Flame Environment., John Samuel Morse Jan 1988

The Combustion Of Carbon-Tetrachloride In A High Temperature Methane-Air Flame Environment., John Samuel Morse

LSU Historical Dissertations and Theses

Stable species concentration and temperature profiles are provided for a series of five CCl$\sb4$/CH$\sb4$/air flames studied on a flat flame burner at atmospheric pressure. A detailed description of the facility used to collect this data is given. This system includes a novel flue gas collection and treatment system. A new gas chromatographic technique used to analyze subatmospheric gas samples is described in detail. This technique utilizes gas syringes for sampling of selected C$\sb1$ and C$\sb2$ hydrocarbons and chlorinated hydrocarbons, as well as fixed gases. Stable species are sampled with aerodynamically cooled quartz microprobes. Temperature measurements are taken with uncoated 0.02 …

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A Molecular Characterization Of An Escherichia Coli Restriction System Specific For 5-Methylcytosine-Containing Dna., Troy Kevin Ross Jan 1988

A Molecular Characterization Of An Escherichia Coli Restriction System Specific For 5-Methylcytosine-Containing Dna., Troy Kevin Ross

LSU Historical Dissertations and Theses

The McrB restriction system in Escherichia coli K-12 is responsible for sequence-specific recognition and inactivation of DNA containing 5-methylcytosine. A derivative of plasmid pUC8 with a 5.5-kilobase pair BglII-EcoRI restriction fragment from the E. coli K-12 chromosome, imparted the wild-type phenotype to the McrB$\sp-$ strain K802. The limits of the McrB region within this DNA fragment were defined by deleting portions of the 5.5-kb insert and assaying for McrB restriction of M.AluI-methylated DNA. Analyses of polypeptides encoded by the McrB region using a maxicell strain revealed that at least three proteins, having molecular weights of approximately 51,000, 39,000, and 33,000, …

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An Investigation Of The Fungus, Balansia Cyperi Edg., And Its Effect On Purple Nutsedge, Cyperus Rotundus L., Mary Elizabeth Stovall Jan 1988

An Investigation Of The Fungus, Balansia Cyperi Edg., And Its Effect On Purple Nutsedge, Cyperus Rotundus L., Mary Elizabeth Stovall

LSU Historical Dissertations and Theses

This study was designed to investigate host specificity of the fungus Balansia cyperi Edg. on Cyperus rotundus L. (purple nutsedge) and to determine the effect of fungus presence on the biology and ecology of the sedge. Isolates of epiphytic Balansias from C. rotundus and C. virens had similar cultural characters, conidium morphology, and extracellular enzyme activity in artificial culture. However, B. cyperi from C. rotundus had a faster growth rate, greater conidium production, and higher temperature optimum than did the isolate from C. virens. Artificial infection of C. rotundus by B. cyperi from C. rotundus was far more successful than …

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Amino Acid Responses Of Olfactory Bulb Cells In The Channel Catfish., Hilary Winfield Thompson Jan 1988

Amino Acid Responses Of Olfactory Bulb Cells In The Channel Catfish., Hilary Winfield Thompson

LSU Historical Dissertations and Theses

Amino acid (AA) responses of olfactory bulb (OB) mitral cells (MC) in the catfish, Ictalurus punctatus, were studied electrophysiologically. A total of 63 cells were recorded in 28 fish in two separate experiments. For the first study, 27 cells in 22 fish were studied with olfactory tract (OT) intact during stimulation with 10$\sp{-6}$ M to 10$\sp{-2}$ M concentrations of 11 AA. MC responses were quantified by interspike interval (ISI) variables sensitive to inhibition (maximum ISI) and excitation (number of action potentials (AP), minimum ISI). APs were also counted in subdivisions to produce a measure sensitive to MC response temporal patterning. …

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Effect Of Controlled Redox Potential And Ph On Heterotrophic Nitrogen Fixation And Mineralization In Crowley Silt Loam Soil., Almoubarakou Ibrahima Toure Jan 1988

Effect Of Controlled Redox Potential And Ph On Heterotrophic Nitrogen Fixation And Mineralization In Crowley Silt Loam Soil., Almoubarakou Ibrahima Toure

LSU Historical Dissertations and Theses

Laboratory investigations were carried out to study the magnitudes and rates of heterotrophic N$\sb2$ fixation and mineralization of organic N as influenced by controlled redox potentials and pH values. Preincubated Crowley silt loam soil suspensions was amended with 0.50% labelled rice straw (41% $\sp{15}$N excess) and incubated for six weeks in the dark. Effects of all combinations of four redox potentials ($-$100, +100, +300, and +500 mV) and two pH values (5 and 7) were studied. At weekly intervals, soil suspension samples were withdrawn and analysed for N$\sb2$ fixation by using the C$\sb2$H$\sb2$ reduction assay, total organic N, extractable NH$\sb4\sp+$-N, …

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Estimation Of Additive And Nonadditive Direct And Maternal Genetic Effects For Reproductive Traits In Beef Cattle., Allen Richard Williams Jan 1988

Estimation Of Additive And Nonadditive Direct And Maternal Genetic Effects For Reproductive Traits In Beef Cattle., Allen Richard Williams

LSU Historical Dissertations and Theses

A total of 4,301 cow exposure records from a four generation rotational crossbreeding study were used to calculate least squares means and heterosis estimates and partition breed and heterotic genetic effects for calving rate (CR), calf survival (CS), weaning rate (WR), calf birth date (CBD) and percent assisted births (PA). Angus (A), Brahman (B), Charolais (C) and Hereford (H) breeds were involved in two-, three- and four-breed rotation systems with the restriction that each breed combination include B. Straightbreds were maintained as controls. Generation, year within generation, breed group of dam within generation and the linear and quadratic effects of …

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Floral Ontogeny And Histogenesis In Leguminosae., Kittie Sue Derstine Jan 1988

Floral Ontogeny And Histogenesis In Leguminosae., Kittie Sue Derstine

LSU Historical Dissertations and Theses

Inflorescence organogeny and floral initiation are investigated topographically (using scanning electron microscopy) and histogenetically in Acacia baileyana (Mimosoideae) and Lupinus havardii (Papilionoideae). Floral ontogeny is investigated topographically in Parkinsonia aculeata (Caesalpinioideae). The paniculate racemes of A. baileyana are constructed of first- and second-order inflorescence meristems. Each produces first-order and second-order bracts, respectively, in acropetal order. Each of the former bracts subtends one second-order inflorescence meristem while the latter bract type subtends a single flower. The radially symmetrical floral meristem of A. baileyana produces calyx members in helical order and corolla members simultaneously with a precocious terminal carpel. Common stamen primordia …

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Analytical-Toxicological Studies Of Environmental Importance., Hessam Ghane Jan 1988

Analytical-Toxicological Studies Of Environmental Importance., Hessam Ghane

LSU Historical Dissertations and Theses

Part One. Acidity and chemical composition of precipitation in Baton Rouge, Louisiana; The synergistic effects of acidity and aluminum on fish. Acid precipitation which consists of both wet precipitation and dry deposition has recently become a significant environmental problem. It has been shown that the effects of acid rain are deleterious to soil, vegetation, aquatic life and buildings. Wet-precipitation-only samplers were used to collect acid rainfalls in the vicinity of Louisiana State University, Baton Rouge and subjected to appropriate chemical analysis for the purpose of characterization of general composition and acidity. About 50% of precipitation is within pH range of …

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Characterization Of The Cellular Immune Defect In Chronic Bovine Paratuberculosis., John Michael Kreeger Jan 1988

Characterization Of The Cellular Immune Defect In Chronic Bovine Paratuberculosis., John Michael Kreeger

LSU Historical Dissertations and Theses

Cattle, naturally infected with Mycobacterium paratuberculosis, were evaluated with respect to immune status. Their ability to express cell mediated immune responses to homologous and heterologous antigens was also evaluated. Lymphocyte and macrophage augmentation was attempted to localize the immune defect in cattle with paratuberculosis. Infected cattle had varying responses to johnin skin test antigen. Lymphocyte blastogenic responses and migration inhibition were, however, consistently positive in infected cattle. Non-infected cattle had positive skin test reactions, blastogenic responses, and migration inhibition after sensitization with M. bovis BCG, M. paratuberculosis, and keyhole limpet hemocyanin. No changes were seen in lymphocyte blastogenic response, migration …

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Response Of Soybean Growth And Dinitrogen-Fixing Ability To Insect-Induced Defoliation., Maurice Blake Layton Jr Jan 1988

Response Of Soybean Growth And Dinitrogen-Fixing Ability To Insect-Induced Defoliation., Maurice Blake Layton Jr

LSU Historical Dissertations and Theses

A series of greenhouse experiments was conducted to investigate the effects of insect-induced defoliation on growth and N$\sb2$-fixing ability of soybean. This research had three major objectives: (1) to examine the effects of different levels of defoliation, (2) to determine the impact of progressive defoliation, and (3) to study the ability of soybeans to recover following defoliation. All experiments were conducted in a similar manner. Larvae of the soybean looper, Pseudoplusia includens (Walker), were used to defoliate soybeans in the vegetative stage of development and the acetylene-ethylene reduction assay was used to provide an indirect measure of N$\sb2$-fixing ability of …

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Compatibility Of Biological Control With Host Plant Resistance And Insecticidal Control In Soybeans., David Boyd Orr Jan 1988

Compatibility Of Biological Control With Host Plant Resistance And Insecticidal Control In Soybeans., David Boyd Orr

LSU Historical Dissertations and Theses

Studies were conducted to investigate the influence of both plant resistance and insecticidal controls used in soybean on several natural enemies of pest insects. There were two major objectives to this research: (1) to examine the effects of an insect herbivore-resistant soybean genotype on relationships between four levels of a trophic system; (2) to determine the influence of the primary insecticides applied to control Louisiana soybean insect pests on survival of a major biological control agent of stink bugs. In the first study, pre-imaginal development of the predatory pentatomid, Podisus maculiventris (Say), was affected by soybean antibiosis in a manner …

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Ultrastructural Studies Of Cell Membrane-Associated Events In Early And Late Stages Of Bovine Coronavirus Replication., Harold Ross Payne Jan 1988

Ultrastructural Studies Of Cell Membrane-Associated Events In Early And Late Stages Of Bovine Coronavirus Replication., Harold Ross Payne

LSU Historical Dissertations and Theses

The early events in the infection of human rectal tumor cells by bovine coronavirus were investigated by immunoelectron microscopy and by studies with lysosomotropic weak bases. Virus particles labeled with colloidal gold were endocytosed by synchronously infected cells and accumulated in vacuoles that resembled secondary lysosomes. Sites of fusion between the virus envelope and the plasmalemma were observed but fusion events along intracellular membranes were not found. Exposure of cells to ammonium chloride or to mythylamine during the first hour of infection had little inhibitory effect on the production of infectious virus. Chloroquine treatments were inhibitory but this effect was …

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Plant Protein Improvement By Genetic Engineering: Use Of Synthetic Genes., Moon Sik Yang Jan 1988

Plant Protein Improvement By Genetic Engineering: Use Of Synthetic Genes., Moon Sik Yang

LSU Historical Dissertations and Theses

The essential amino acid composition of plant foodstuffs is very important, especially in the developing countries where people very heavily depend on plant proteins from a single source. In these situations, it would be highly beneficial to 'engineer' the plant to produce proteins with a balanced essential amino acid content. Recombinant DNA technology and Agrobacterium-based vector systems offer a novel approach to modify plant proteins. Several attempts with some encouraging results have been made to express plant storage protein genes in transgenic plants. However, improvement of the quality of plant protein using these techniques is in an early stage. In …

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Electronic Structure Of Clusters: Applications To High-T(C) Superconductors., Han Chen Jan 1988

Electronic Structure Of Clusters: Applications To High-T(C) Superconductors., Han Chen

LSU Historical Dissertations and Theses

We present a method of studying the electronic structure of clusters by ab initio, self-consistent, local spin density functional calculations. The linear combination of Gaussian orbitals (LCGO) method has been adopted in developing a general cluster program. A variational charge fitting procedure is used in the evaluation of the matrix elements of the electrostatic potential, and a separate least-squares fitting procedure is used in regard to the exchange-correlation potential. Self-consistent solutions have been obtained using this program for the Ba$\sb4$Cu$\sb2$O$\sb7$ clusters as a portion of the Cu-O chain in the high-T$\sb{c}$ superconductor YBa$\sb2$Cu$\sb3$O$\sb7$. Four different charge states of Ba$\sb4$Cu$\sb2$O$\sb7$ are …

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Development Of Techniques For Studying Interactions Of Organic Compounds With Complex Solid Matrices., Devi Chalasani Jan 1988

Development Of Techniques For Studying Interactions Of Organic Compounds With Complex Solid Matrices., Devi Chalasani

LSU Historical Dissertations and Theses

A combination of high resolution solid state nuclear magnetic resonance spectroscopy, and solvent extractions with solvents of varying polarities was used to identify the mechanism of interaction between hazardous organic and/or inorganic wastes and a Portland Cement based system. Ethylene glycol (EG), p-bromophenol (pBP), p-chlorophenol (pCP), p-(aminomethyl)phenol (pAMP) were used as model organic wastes, and cadmium and lead hydroxide sludges were used as model inorganic wastes. Type I Portland Cement, with and without soluble silicate additive, was solidified with water and various waste mixtures. The soldified samples were examined by solvent extractions and by NMR at various time intervals. Chemical …

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Free Radical Production From Criegee Ozonides., James Conrad Ewing Jan 1988

Free Radical Production From Criegee Ozonides., James Conrad Ewing

LSU Historical Dissertations and Theses

Allylbenzene ozonide (ABO), a model for poly-unsaturated fatty acid (PUFA) ozonides, is shown to initiate the autoxidation of methyl linoleate (18:2ME) at 37$\sp\circ$C under 760 torr of oxygen. This process is inhibited by d-alpha-tocopherol ($\alpha$-T) and 2,6-di-tert-butyl-4-methylphenol (BHT). Rates of initiated autoxidation were measured by appearance of conjugated diene (C.D.) and oxygen-uptake experiments; rates are proportional to the square root of ABO concentration, implying that the usual free radical autoxidation rate law is obeyed. Activation parameters for the thermal decomposition of ABO were determined under N$\sb2$ in the presence of radical scavengers and found to be E$\sb{\rm a}$ = 28.2 …

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Free Radical Chemistry In Smoke From Household And Cellulosic Materials, Automobile Fuel, And Perfluoropolymers., Thomas M. Lachocki Jan 1988

Free Radical Chemistry In Smoke From Household And Cellulosic Materials, Automobile Fuel, And Perfluoropolymers., Thomas M. Lachocki

LSU Historical Dissertations and Theses

Free radicals have been detected in smoke resulting from the combustion of household and cellulosic materials, automobile fuel, and perfluoropolymers. Materials were pyrolyzed by a variety of methods, but the most reproducible results were obtained by heating the materials in a heated quartz tube. The smoke was reacted with $\alpha$-phenyl-N-t-butylnitrone (PBN), and the resulting nitroxide spin adducts were detected by electron spin resonance. Oxygen-centered radical spin adducts predominate, lesser amounts of carbon-centered radical spin adducts and an oxidation product of PBN were also observed when smoke from several cellulosic materials, dried exterior paint, polyethylene, rubber, and automobile exhaust was allowed …

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Peptide Grafting To Aminated Cellulose And Related Aminated Condensation Polymers., Soo Lee Jan 1988

Peptide Grafting To Aminated Cellulose And Related Aminated Condensation Polymers., Soo Lee

LSU Historical Dissertations and Theses

Natural and synthetic macroinitiators with primary amino substituents have been synthesized by one of the following techniques: (1) cyanoethylation of cellulose followed by diborane reduction to produce O-(3-aminopropyl)cellulose, (1), (2) reduction of 6-azido-6-deoxycellulose acetate with 1,3-propanedithiol to 6-amino-6-deoxycellulose acetate, (2), (3) reduction of 2,3-O-diphenylcarbamoyl-6-azido-6-deoxycellulose with 1,3-propanedithiol to 2,3-O-diphenylcarbamoyl-6-amino-6-deoxycellulose, (3), (4) nitration then SnCl$\sb2$ reduction of poly(arylene ether sulfone) to produce poly(3-amino-arylene ether sulfone), (4), (5) phthalimidomethylation them followed by hydrazinolysis to yield poly(3-aminomethylarylene ether sulfone), (5), and (6) LiAlH$\sb4$ reduction of poly(2-cyano-1,3-phenylene arylene ether) to poly(2-aminomethyl-1,3-phenylene arylene ether), (6). Heterogeneous grafting of $\gamma$-benzyl-L-glutamate-N-carboxyanhydride, (BLG-NCA), onto polymer (1) resulted in a …

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Effects Of Aluminum On Magnesium Uptake By Ryegrass Lolium Multiflorum Lam., Zdenko Rengel Jan 1988

Effects Of Aluminum On Magnesium Uptake By Ryegrass Lolium Multiflorum Lam., Zdenko Rengel

LSU Historical Dissertations and Theses

Aluminum impairs uptake of Mg$\sp{2+}$ by plants grown in soil or in nutrient solution, but mechanisms of this inhibition are not understood. Experiments were prepared to elucidate the effects of pH (6.0 vs. 4.2) and Al$\sp{3+}$ activity (0, 6.6, and 26 umol L$\sp{-1}$) in nutrient solution on the kinetics of net Mg$\sp{2+}$ uptake by 23-day-old plants of ryegrass (Lolium multiflorum Lam., cultivars Gulf and Wilo). The kinetics of Mg$\sp{2+}$ uptake was resolved in: (1) a transpiration-dependent uptake component, (2) a metabolically-mediated, discontinuous saturable component that is Al$\sp{3+}$-sensitive and 4-(chloromercuri)benzenesulfonic acid (PCMBS)-resistant, and (3) a linear, carbonyl cyanide 3-chlorophenylhydrazone (CCCP)-resistant, Al$\sp{3+}$-sensitive …

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Dynamic Headspace Sampling And Chromatographic And Mass Spectrometric Investigations Of Volatile Flavor Components In Red Swamp Crayfish (Procambarus Clarkii) Hepatopancreatic Tissue., Stephen S. Williams Jan 1988

Dynamic Headspace Sampling And Chromatographic And Mass Spectrometric Investigations Of Volatile Flavor Components In Red Swamp Crayfish (Procambarus Clarkii) Hepatopancreatic Tissue., Stephen S. Williams

LSU Historical Dissertations and Theses

This analytical food flavor study concentrated on the development and application of improved analytical techniques to investigate volatile flavor components in crayfish (Procambarus clarkii) hepatopancreatic tissue. This work consisted of four main parts. The first part dealt with the development of an improved dynamic headspace sampling procedure for the sampling and concentration of volatile flavor components in the headspace of high moisture foods. The second section described the successful application of this improved procedure for chromatographic and mass spectrometric investigation of dynamic headspace volatile flavor components of crayfish hepatopancreatic tissue. The third part discussed the quantitative determination of these volatile …

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Molecular Analysis Of Mutant And Wild Type Alcohol Dehydrogenase Alleles From Drosophila., Mark Andrew Batzer Jan 1988

Molecular Analysis Of Mutant And Wild Type Alcohol Dehydrogenase Alleles From Drosophila., Mark Andrew Batzer

LSU Historical Dissertations and Theses

Wild type alcohol dehydrogenase polypeptides (ADH) from Drosophila melanogaster transformants were examined using western blots and polyclonal antiserum specific for Drosophila melanogaster ADH. These data indicate that ADH from Hawaiian drosophilids was similar in molecular weight to Drosophila melanogaster ADH, but that the isoelectric points of the Hawaiian electromorphs were distinct. Therefore it was evident that western blots could be used to characterize ADH from different species of Drosophila. Mutants induced in Drosophila spermatozoa at the alcohol dehydrogenase (Adh) locus using X-rays, 1-ethyl-1-nitrosourea (ENU) or ethyl methanesulfonate (EMS) were characterized using genetic complementation tests, western blots, Southern blots, northern blots …

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Path-Coefficient Analysis: A Study Of Phenotypic, Broad-Sense And Narrow-Sense Variation In Sugarcane., Kenneth Albert Gravois Jan 1988

Path-Coefficient Analysis: A Study Of Phenotypic, Broad-Sense And Narrow-Sense Variation In Sugarcane., Kenneth Albert Gravois

LSU Historical Dissertations and Theses

The variance-covariance structure of a Louisiana sugarcane (Sacchum spp.) population was estimated and used to calculate correlation coefficients (phenotypic, broad-sense genotypic and additive genetic), narrow-sense heritability and measures of additive genetic variation and gain under selection. Four progeny from each of 20 crosses were grown in plantcane, first ratoon and second ratoon crops at the St. Gabriel Research Station of the Louisiana Agricultural Experiment Station. Broad-sense genotypic and phenotypic correlations were calculated and subjected to path-coefficient analysis to study direct and indirect effects in a set of cause and effect relationships involving sucrose yield. Broad-sense genotypic relationships are useful to …

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Pseudomonas Sp. Strain Pg2982: Uptake Of Glyphosate And Cloning Of A Gene Which Confers Increased Resistance To Glyphosate., Joseph E. Fitzgibbon Jan 1988

Pseudomonas Sp. Strain Pg2982: Uptake Of Glyphosate And Cloning Of A Gene Which Confers Increased Resistance To Glyphosate., Joseph E. Fitzgibbon

LSU Historical Dissertations and Theses

Chapter 1. Pseudomonas sp. strain PG2982 has the ability to use the phosphonate herbicide, glyphosate, as a sole phosphorus source. Glyphosate uptake occurs at a maximum in the late log phase of growth and is induced by phosphate starvation. Uptake is inhibited by phosphate and arsenate, but not by the amino acids glycine and sarcosine. The K$\sb{\rm m}$ and V$\sb{\rm max}$ for glyphosate uptake were calculated to be 23uM and 0.97nmoles/mg dry wt/min, respectively. A phosphate transport system with a broad substrate specificity seems to be responsible for glyphosate uptake. Chapter 2. Pseudomonas sp. strain PG 2982 is highly resistant …

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