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1996

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Synthesis Of Phosphonate Derivatives And Phosphonate Peptide Analogues., Maria De Fatima Fernandez Jan 1996

Synthesis Of Phosphonate Derivatives And Phosphonate Peptide Analogues., Maria De Fatima Fernandez

LSU Historical Dissertations and Theses

A general method for the preparation of a wide variety of phosphonate derivatives, including phosphonamides, thiophosphonamides, thiosphonates, and dithiophosphonates, from reduced phosphorus intermediates has been developed. Esters (or thioesters) of H-phosphinates are converted to the highly reactive phosphonochloridites by non-oxidative activation with dichlorotriphenylphosphorane. The phosphonochloridites react readily with alcohols, amines and thiols and after in situ oxidation or sulfurization, phosphonate derivatives can be isolated in moderate to very good yields (47-85%). This method was used to synthesize a thiophosphonate dipeptide, Boc-Val-$\Psi$(P(S)(OtBu)O) Ala-OCH$\sb3$ (15b), two thiophosphonamide dipeptides, Boc-Val-$\Psi$ (P(S)(OtBu)NH) Gly-OCH$\rm\sb2CH\sb3$ (16b) and Fmoc-Aib-$\Psi$ (P(S)(OBn)NH) Gly-OCH$\rm\sb2CH\sb3$ (20), and two phosphonate dipeptides, Fmoc-Aib-$\Psi$ …

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Chemical Effects On Microbial And Sensory Qualities Of Catfish In Planktonic And Dynamic Systems., Michael Adrain Land Jan 1996

Chemical Effects On Microbial And Sensory Qualities Of Catfish In Planktonic And Dynamic Systems., Michael Adrain Land

LSU Historical Dissertations and Theses

Listeria monocytogenes has the potential to be a serious pathogen for the compromised health segment of our population (immunocompromised, young, elderly and the pregnant). While the infectious dose is generally believed to be high 1.0 $\times$ 10$\sp6$, infectious dosages of 1.0 $\times$ 10$\sp3$ have been reported. Listeria monocytogenes poses a threat because of several factors: ubiquity in nature, isolation from fresh/salt waters, soil, ruminates and 17% of the human population. Listeria monocytogenes can colonize surfaces within 20 minutes, evade sanitizing, and is capable of growth from 37$\sp\circ$C to below refrigeration temperature. Fish and seafoods are high in water activity and …

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Physical And Functional Characterization Of Long Terminal Repeat Of Equine Infectious Anemia Virus., Soo Ho Kim Jan 1996

Physical And Functional Characterization Of Long Terminal Repeat Of Equine Infectious Anemia Virus., Soo Ho Kim

LSU Historical Dissertations and Theses

The U3 region of long terminal repeat (LTR) of equine infectious anemia virus (EIAV) contains transcriptional regulatory elements. To identify the elements in prototype (P), fetal donkey dermal cell-adapted (A), and two variant (V) EIAV LTRs, DNase I footprinting, gel shift, and transient gene expression assays were performed. The assays used U937 monocytic cells which can be induced into macrophages by 12-O-tetradecanoylphorbol-13-acetate (TPA). For study of AP1 sites, c-Jun/AP1 was also used. Footprinting with nuclear extracts from TPA-induced and uninduced U937 cells localized methylated DNA-binding protein (MDBP), PEA2, AP1, PU.1, and CCAAT enhancer-binding protein (C/EBP) sites as common elements in …

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Dinitropyrenes: Nitroreduction Processes And Evaluation Of Indices Of Exposure., Matthew Jerome Krautmann Jan 1996

Dinitropyrenes: Nitroreduction Processes And Evaluation Of Indices Of Exposure., Matthew Jerome Krautmann

LSU Historical Dissertations and Theses

Investigations were conducted to identify biomarkers of exposure to dinitropyrenes (DNPs), which are mutagenic and carcinogenic residues of incomplete combustion. One possible biomarker, a DNP-protoporphyrin IX adduct, was not found in analytically useful quantities in liver tissue or in bile. Clastogenicity, a biomarker of effect, also was found to be absent in marrow cells following subchronic exposure of rats to DNPs by gavage. Solubility studies, used as a basis for dosing guidelines, revealed that DNPs are relatively insoluble in both aqueous and lipid tissue compartments. Calculated log P values indicated that the reduced metabolites of DNPs probably are more soluble …

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Fluorescence Studies Of Ecori Restriction Endonuclease Structure And Dynamics., Wei Liu Jan 1996

Fluorescence Studies Of Ecori Restriction Endonuclease Structure And Dynamics., Wei Liu

LSU Historical Dissertations and Theses

Sequence specific protein-DNA interaction involves changes in protein conformation and dynamics. Research work involved in this thesis is the study of structure and dynamics of EcoRI restriction endonuclease N-termini. The N-termini of EcoRI endonuclease has been shown to be essential for DNA cleavage and also stabilize EcoRI-DNA complex. But they are not resolved in the X-ray crystal structure. An Asn3Cys mutation was made at the N-termini by site-directed mutagenesis and the mutant was subjected to cysteine crosslinking, pyrene labeling and fluorescence studies. Chemical crosslinking of Asn3Cys mutant and steady-state fluorescence studies of pyrene-labeled mutant indicated that the N-termini are in …

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Characterization Of Variant Equine Infectious Anemia Virus Long Terminal Repeat Sequences., Charles Richard Madden Jan 1996

Characterization Of Variant Equine Infectious Anemia Virus Long Terminal Repeat Sequences., Charles Richard Madden

LSU Historical Dissertations and Theses

Equine infectious anemia virus (EIAV) is the causative agent of a persistent disease in horses. The long terminal repeat (LTR) region of EIAV contains the enhancer and promoter elements necessary for transcription of the proviral genome. The LTR is also prone to a high degree of sequence variability between different virus isolates. Sequence alignments of LTR variants from both tissue culture-adapted strains of the virus as well as sequential horse isolates showed a high degree of sequence variability between variants. Sequence variability was further localized to a hypervariable region approximately 60 bp upstream of the TATA box. This region contained …

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Characterization Of Physiological Changes In Roots Grown In Spaceflight Conditions: A Comparison Of Nutrient Delivery Technologies., David Marshall Porterfield Jan 1996

Characterization Of Physiological Changes In Roots Grown In Spaceflight Conditions: A Comparison Of Nutrient Delivery Technologies., David Marshall Porterfield

LSU Historical Dissertations and Theses

The best strategy for providing food and maintaining the environment on long-duration space missions is a bioregenerative life support system based on the growth of higher plants. Before such a system can be implemented, a better understanding of plant growth in space will have to be achieved. Little is known about the role of gravity-dependent physical processes in normal physiological function. A series of ground-based and spaceflight experiments was conducted to examine root oxygen availability in microgravity nutrient delivery systems. In spaceflight experiments Arabidopsis thaliana (L.) Heynh. plants were analyzed for changes in root medium redox potential and root alcohol …

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Toxicity Of Polycyclic Aromatic Hydrocarbons To Benthic Invertebrates., Guilherme R. Lotufo Jan 1996

Toxicity Of Polycyclic Aromatic Hydrocarbons To Benthic Invertebrates., Guilherme R. Lotufo

LSU Historical Dissertations and Theses

Polycyclic aromatic hydrocarbons (PAHs) are ubiquitous contaminants in aquatic environments. Because of their hydrophobicity, PAHs accumulate in bed sediments and pose a risk to the benthos. Information on the toxicity of sediment-associated PAHs is, however, limited and more information is needed to improve sediment quality-criteria and ecological-risk assessments. My research focused on improving our current knowledge of the acute and, especially, the sublethal effects of sediment-associated PAHs to aquatic invertebrates. Representatives of two phylogenetically distinct benthic invertebrate groups, freshwater tubificid oligochaetes and estuarine meiobenthic harpacticoid copepods, were used. Organisms were exposed to a range of concentrations of sediment-amended contaminants in …

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Immunocytochemical Localization Of Gonadotropins, Growth Hormone, And Prolactin In Equine Pituitary., Mohammad Saeed Rahmanian Jan 1996

Immunocytochemical Localization Of Gonadotropins, Growth Hormone, And Prolactin In Equine Pituitary., Mohammad Saeed Rahmanian

LSU Historical Dissertations and Theses

The present research was performed to characterize immunoreactive (ir) pituitary cells in the equine species. Two experiments were performed to measure the prevalence of single- and double-hormone labeled gonadotropes, lactotropes, somatotropes, and mammosomatotropes. In Experiments 1 and 2, pituitaries from three intact pony mares were processed for ultrastructural evaluation of cells stained for luteinizing hormone (LH), follicle-stimulating hormone (FSH), prolactin (PRL), and growth hormone (GH). Primary antibodies and gold-conjugated antibodies were used to double-stain ir-cells. The percentages of pituitary cells stained for each hormone in intact mares were: total gonadotropes, 15 to 32%; LH-only, 2 to 16%; FSH-only, 1 to …

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Paleoindicators Of Changing Water Conditions In Louisiana Estuaries., Michael Lewis Parsons Jan 1996

Paleoindicators Of Changing Water Conditions In Louisiana Estuaries., Michael Lewis Parsons

LSU Historical Dissertations and Theses

Sediment cores were collected to study the development of eutrophication and hydrological changes in coastal Louisiana. The cores were taken at marsh sites hypothesized to be influenced primarily by riverine inputs (Fourleague Bay-FLB), localized activities (Terrebonne Bay-TSMP), and both riverine and localized processes (Airplane Lake-APL). The sediment cores represented time frames ranging from 330 years (APL) to 70 years (TSMP) BP according to core dating results. Sediment core samples were analyzed for diatoms, other microfossils, pigments, biogenic silica, and sediment characteristics. Additionally, land use records were utilized as a proxy of anthropogenic activities, and to aid in the interpretation of …

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The Effects Of Timber Management Activities On Understory Plant Succession In Young Loblolly Pine (Pinus Taeda) Plantations., Donald Paul Reed Jan 1996

The Effects Of Timber Management Activities On Understory Plant Succession In Young Loblolly Pine (Pinus Taeda) Plantations., Donald Paul Reed

LSU Historical Dissertations and Theses

An understory vegetative succession study was conducted on the LSU Lee Memorial Forest near Bogalusa, Louisiana. Research blocks were established within fifteen-year-old overstocked loblolly pine (Pinus taeda) stands, in specific areas classified as with or without a history of prescribed burning for the current timber rotation. Silvicultural treatments involved precommercially thinning randomly selected blocks to various stand densities, along with the establishment of unthinned control areas. Growth rates of residual trees were determined from tree diameter measurements, on all timbered plots. Burn-history areas received a further treatment, involving the mechanical destruction of all timber on specified areas, followed by site-preparation …

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Interrelationships Between Meloidogyne Incognita And Rotylenchulus Reniformis On Soybean., Salliana Ryan Stetina Jan 1996

Interrelationships Between Meloidogyne Incognita And Rotylenchulus Reniformis On Soybean., Salliana Ryan Stetina

LSU Historical Dissertations and Theses

The replacement series approach was used to evaluate competition between Meloidogyne incognita (Mi) and Rotylenchulus reniformis (Rr). In greenhouse tests, soil in pots containing 'Davis' soybean was not infested or infested with 1,000 vermiform nematodes in the following Mi:Rr ratios: 100:0, 75:25, 5:50, 25:75, and 0:100. After 86 days, relative nematode yields (RNYs) (number of each species in mixed culture divided by number in nonmixed culture) were calculated based on soil populations. Calculated values were plotted and the resulting line compared with a reference line representing equal inter- and intraspecific competition. RNYs for Mi were higher than predicted where Mi …

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The Effect Of Silvicultural Treatments On Certain Mechanical And Physical Properties Of Loblolly Pine Wood Composites., Todd Finley Shupe Jan 1996

The Effect Of Silvicultural Treatments On Certain Mechanical And Physical Properties Of Loblolly Pine Wood Composites., Todd Finley Shupe

LSU Historical Dissertations and Theses

The effects of silvicultural treatments on mechanical and physical properties of loblolly pine (Pinus taeda L.) wood composites, veneer tensile and bending properties, and basic chemical properties were investigated. Stands managed in a plantation setting showed higher extractive contents. Holocellulose and alpha-cellulose were minimally affected by the silvicultural strategies. Klason lignin showed an inverse relationship with holocellulose. The effect of wood type was significant for the extractives because the innerwood region yielded much greater values than the outerwood. Holocellulose and alpha-cellulose increased in concentration from innerwood to outerwood. Veneer tensile strength was significantly affected by silvicultural practice, but other mechanical …

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Control Of African Striga Species By Natural Products From Native Plants., Joseph Kipronoh Rugutt Jan 1996

Control Of African Striga Species By Natural Products From Native Plants., Joseph Kipronoh Rugutt

LSU Historical Dissertations and Theses

Obligate root-parasitic flowering plants of the genus Striga (family Scrophulariaceae) cause considerable yield reductions of various crops in tropical and semi-tropical countries. Mature Striga species (witchweeds) plants produce copious quantities of minute seeds which remain dormant in the soil for many years until exudates from roots of various host plants induce germination. Economically effective means of control of Striga species are not yet available for small-scale farmers in developing countries. In the present study data is presented which indicate that the two most effective Striga control measures are crop rotation and suicidal germination. For the first time we have analyzed …

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New Export Controls For Chemicals On The Horizon?, Rex Zedalis Jan 1996

New Export Controls For Chemicals On The Horizon?, Rex Zedalis

Articles, Chapters in Books and Other Contributions to Scholarly Works

No abstract provided.

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A Winter Record Of The Gray Vireo From San Luis Potosi, Mexico, Adam J. Fry, Octavio R. Rojas-Soto, Adolfo G. S. Jan 1996

A Winter Record Of The Gray Vireo From San Luis Potosi, Mexico, Adam J. Fry, Octavio R. Rojas-Soto, Adolfo G. S.

Western Birds

No abstract provided.

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Western Birds, Index, Volume 27, 1996, Jack W. Schlotte, Philip Unitt Jan 1996

Western Birds, Index, Volume 27, 1996, Jack W. Schlotte, Philip Unitt

Western Birds

No abstract provided.

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Analysis Of The Influence Of Genotype On Cayenne Pepper Fruit-Receptacle Detachment., Kay P. Gersch Jan 1996

Analysis Of The Influence Of Genotype On Cayenne Pepper Fruit-Receptacle Detachment., Kay P. Gersch

LSU Historical Dissertations and Theses

Two genotypes of cayenne pepper, Capsicum annuum L., were identified that differ significantly in ease of fruit detachment. Both greenhouse and field-grown plants of these genotypes, Cajun 1-9027 and Cap-9004, were investigated for differences in cell type and organization at the fruit-receptacle junction. Scanning electron microscopy revealed that mature fruit of Cajun 1-9027, which did not separate, exhibited a distinct region of sclerified cells that extended from the periphery of the fruit into the receptacle for at least 15 cell layers. In contrast, mature fruit of the more readily detachable Cap-9004 had fewer sclerified cells at the region of detachment. …

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Medical Compliance In Hiv-Infected Patients: An Analysis Of Outpatient Clinic Attendance., Jennifer B. Mcclure Jan 1996

Medical Compliance In Hiv-Infected Patients: An Analysis Of Outpatient Clinic Attendance., Jennifer B. Mcclure

LSU Historical Dissertations and Theses

Currently there is no cure for HIV/AIDS. The only way to deter progression of this disease is through regular prophylactic and curative treatment regimens. Thus, it is critical that patients are compliant with their outpatient medical appointments. Despite this, high rates of noncompliance have been reported among patients with HIV/AIDS. In addition, little attention has been directed toward establishing causal factors of this noncompliance. The present study represents one of the first efforts to elucidate psychosocial, illness, and demographic factors associated with compliance with outpatient, HIV-specific treatments. The results of this study indicate noncompliance with medical appointments is a significant …

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The Use Of Communication Facilitators With Severely Brain Injured Non-Responsive Adults., Alisa Judith Mendoza Jan 1996

The Use Of Communication Facilitators With Severely Brain Injured Non-Responsive Adults., Alisa Judith Mendoza

LSU Historical Dissertations and Theses

Slow-to-Recover (STR) individuals are a subset of the neurologically impaired population who remain non-responsive for extended periods of time before beginning to demonstrate improvement in cognitive, communicative, or motor function. This investigation focuses on the development and implementation of a facilitator-based intervention program carried out with an STR brain injured adult residing in a long-term care facility. The model involved: (1) sensory stimulation techniques to increase responses to external stimuli, (2) augmentative techniques which enabled the subject to control his immediate environment and, (3) training of qualified residents within the facility to act as communication facilitators. Ethnographic procedures were employed …

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Perennial Weed Control Programs In Succession Planted And Fallowed Sugarcane (Saccharum Spp.) Fields., Donnie Keith Miller Jan 1996

Perennial Weed Control Programs In Succession Planted And Fallowed Sugarcane (Saccharum Spp.) Fields., Donnie Keith Miller

LSU Historical Dissertations and Theses

Studies were conducted over two years to compare weed control programs in succession planted sugarcane and in fallowed sugarcane fields. Glyphosate combined with tillage during the summer fallow period was more effective in controlling bermudagrass than tillage alone. Bermudagrass ground cover 240 days after planting ranged from 7 to 47% when glyphosate plus tillage was followed by atrazine after planting and pendimethalin plus atrazine in February. Bermudagrass ground cover was no more than 5% with applications of terbacil after planting and metribuzin in February. Cane and sugar yields were equivalent for the herbicide/tillage treatments even though bermudagrass control differed. In …

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Regulation Of Interrenal Steroidogenesis In Elasmobranchs., Brian Scott Nunez Jan 1996

Regulation Of Interrenal Steroidogenesis In Elasmobranchs., Brian Scott Nunez

LSU Historical Dissertations and Theses

This study investigated the steroidogenic enzymes of the elasmobranch interrenal. First, biochemical characteristics of cytochrome P450c21 hydroxylase (P450c21) and 3$\beta$-hydroxysteroid dehydrogenase (3$\beta$-HSD) were determined with incubations of the microsomal fraction of Carcharhinus limbatus (blacktip shark) interrenal tissue. Second, molecular reagents were obtained by isolating and sequencing partial cDNA clones encoding the elasmobranch steroidogenic enzymes cytochrome P450 side chain cleavage (P450scc) and 3$\beta$-HSD from blacktip shark and Daysatis americana (southern stingray) interrenal. Finally, the regulation of Daysatis sabina (Atlantic stingray) interrenal steroidogenesis by peptide hormones such as corticotropin (ACTH) and angiotensin II was investigated by in vitro incubations of interrenal tissue. …

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Relationship Of Catecholamines And Glucocorticoids To Lymphoproliferation Of Equine Peripheral Blood Mononuclear Cells., Lavanya Potla Jan 1996

Relationship Of Catecholamines And Glucocorticoids To Lymphoproliferation Of Equine Peripheral Blood Mononuclear Cells., Lavanya Potla

LSU Historical Dissertations and Theses

Stress has been related to increased plasma epinephrine (E), norepinephrine (NE), and glucocorticoids. These compounds produce immunomodulatory effects by interacting with hormone receptors on or in various immune cells. This project assessed the effects of stress on equine influenza virus (EIV)-specific and mitogen-induced lymphoproliferation of peripheral blood mononuclear cells (PBMCs) in relation to stress-induced changes in E, NE, and cortisol. In vitro effects of amines on proliferative responses and glucocorticoid receptor (GR) assays were done as a secondary measure of hormone and neurotransmitter interactions with the immune system. Time-dependent, saturable-specific hormone binding to GRs was abolished by heat treatment and …

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Nesting And Food Habits Of Barn Owls In South Florida, Peter G. David Jan 1996

Nesting And Food Habits Of Barn Owls In South Florida, Peter G. David

Florida Field Naturalist

No abstract provided.

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Late Breeding Records Of A Red-Headed Woodpecker And A Summer Tanager In Florida, Douglas B. Mcnair Jan 1996

Late Breeding Records Of A Red-Headed Woodpecker And A Summer Tanager In Florida, Douglas B. Mcnair

Florida Field Naturalist

No abstract provided.

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Gull-Billed Tern Nesting On A Roof In Northwest Florida, Lara M. Coburn Jan 1996

Gull-Billed Tern Nesting On A Roof In Northwest Florida, Lara M. Coburn

Florida Field Naturalist

No abstract provided.

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Fall Report: August-November 1995, Bill Pranty Jan 1996

Fall Report: August-November 1995, Bill Pranty

Florida Field Naturalist

No abstract provided.

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Winter Report: December 1995–February 1996, Bill Pranty Jan 1996

Winter Report: December 1995–February 1996, Bill Pranty

Florida Field Naturalist

No abstract provided.

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Recent Publications On Waders 67, Henk Koffijberg Jan 1996

Recent Publications On Waders 67, Henk Koffijberg

Wader Study Group Bulletin

No abstract provided.

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Back Matter (Pdf), Wader Study Group Bulletin Jan 1996

Back Matter (Pdf), Wader Study Group Bulletin

Wader Study Group Bulletin

No abstract provided.

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