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Ecology Of Erwinia Chrysanthemi, Causal Agent Of Bacterial Stem And Root Rot On Sweet Potato And Etiology Of Souring., Valmir Duarte Jan 1990

Ecology Of Erwinia Chrysanthemi, Causal Agent Of Bacterial Stem And Root Rot On Sweet Potato And Etiology Of Souring., Valmir Duarte

LSU Historical Dissertations and Theses

During three seasons, mother storage roots of Beauregard sweetpotato were inoculated with Erwinia chrysanthemi in March, and the pathogen was recovered from them the day they were bedded, 7 days later, and at the first and second pullings of slips as well as from underground stems at harvest in September and October of the first and second transplantings, respectively. Little stem rot occurred in the fields during the three seasons. Thirteen strains of E. chrysanthemi, 8 isolated originally from sweetpotato and 5 from other hosts, and one strain of E. carotovora subsp. carotovora were inoculated on sweetpotato and 12 different …

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The Relation Between Depression Scores And Social Skills Scores In Children: A Cross-Sectional Study Of Self-Report And Parent-Report Measures., Larry Ray Friedt Jan 1990

The Relation Between Depression Scores And Social Skills Scores In Children: A Cross-Sectional Study Of Self-Report And Parent-Report Measures., Larry Ray Friedt

LSU Historical Dissertations and Theses

The relationship between depressive symptoms and social skills in children was examined. Three depression measures (Children's Depression Inventory, Reynolds' Child/Adolescent Depression Scale, Depression Self-Rating Scale) and two social skills measures (Matson Evaluation of Social Skills with Youngsters, Social Skills Rating System) were used to obtain parent-report and self-report data. One hundred fifty-eight children in six different grades (3rd, 4th, 6th, 7th, 9th, 10th) were the subjects of the study. Reliability of each measure was examined using internal consistency reliability coefficients (Cronbach's alpha) which indicated all the measures except the Depression Self-Rating Scale parent-report yielded coefficients of.80 or greater. The validity …

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Evaluation Of Selected Pulmonary Function Tests In Resting Thoroughbred Horses Having Reversible, Experimentally Induced Respiratory Dysfunctions., Alan John Guthrie Jan 1990

Evaluation Of Selected Pulmonary Function Tests In Resting Thoroughbred Horses Having Reversible, Experimentally Induced Respiratory Dysfunctions., Alan John Guthrie

LSU Historical Dissertations and Theses

The purpose of the first part of this study was to develop computerized techniques for automation of instrument calibration, data collection and calculation of indices of pulmonary mechanical function in resting and exercising horses. The microcomputer system developed enabled a single trained technician to reliably operate the equipment in an equine pulmonary mechanics laboratory. The first experiment investigated the temporal effects of histamine and methacholine aerosols on indices of pulmonary mechanics derived from the linear equation of motion. Data calculated on a breath-by-breath basis were too variable to be reliably modeled. Following application of averaging techniques, the temporal effects of …

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Beta-Endorphin Receptors On Equine Lymphocytes: Relationship To Immune Function And Exercise., Jena Gosselink Hamra Jan 1990

Beta-Endorphin Receptors On Equine Lymphocytes: Relationship To Immune Function And Exercise., Jena Gosselink Hamra

LSU Historical Dissertations and Theses

Current evidence suggests that endogenous opioids are released in response to various stressors and that these opioids interact with cells of the immune system, and modulate immune function. However, data substantiating this are conflicting. Therefore, this study endeavored to clarify the role of beta-endorphin (BE) in exercise and immune function. Beta-endorphin exhibited a diurnal rhythm in the horse with peak plasma levels occurring at 0900 hours. Analgesia, tachycardia and mydriasis were also observed at this time, mimicking the effects of morphine in the horse. Therefore, subsequent experiments were performed at 0900 hours during times of increased basal opioid activity. Beta-endorphin …

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Assessment Of Athletic Potential And Augmentation Of Performance In Thoroughbred Racehorses., John Daniel Harkins Jan 1990

Assessment Of Athletic Potential And Augmentation Of Performance In Thoroughbred Racehorses., John Daniel Harkins

LSU Historical Dissertations and Theses

The purposes of this dissertation were to (1) determine running abilities of horses on the racetrack, (2) design treadmill standard exercise tests (SETs) to measure exercise variables that correlate with racetrack performance, and (3) assess the influence of training, competition, and ergogenic aids on performance. Run times of 25 Thoroughbreds were determined during solo and competitive track runs of 1200, 1600, and 2000 meters. Cardiac, respiratory, and hematologic variables were later measured during treadmill SETs. Variables were correlated with average run times. Heart rate scores, V$\sb{200}$, plasma lactate values, and maximal oxygen uptake correlated best with performance. Interval and conventional …

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An Adaptive Control System For Biological And Robotic Simulations., Sunggyu Kwon Jan 1990

An Adaptive Control System For Biological And Robotic Simulations., Sunggyu Kwon

LSU Historical Dissertations and Theses

An adaptive control algorithm based on Albus' CMAC (Cerebellar Model Articulation Controller) was studied with emphasis on how to build a Multilayered CMAC Control System. This concept has been devised to circumvent the excessive memory requirements of CMAC controllers for complex control systems with many inputs. The Neighborhood Sequential Training technique was devised as a general CMAC training technique. This training technique is straightforward to implement and well matched to CMAC's memory generalization. A two-layered CMAC control module was simulated for a six dimensional CMAC problem of trajectory control for a six degree of freedom manipulator. Layering was accomplished by …

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Stress And Headache., Thomas Hamilton Mosley Jr Jan 1990

Stress And Headache., Thomas Hamilton Mosley Jr

LSU Historical Dissertations and Theses

Stress is the most frequently cited precipitant of both migraine and muscle-contraction headache. Although stress is thought to play a causal role in the etiology of headache, past research has relied solely on cross-sectional designs and between-subjects data analytic techniques, thus severely restricting conclusions regarding causality and obscuring potentially meaningful individual variability. The present investigation provided a partial replication and extension of prior research on the relation between minor stress and headache and attempted to redress a number of prior methodological shortcomings. A longitudinal design and within subject, lagged, time-series regression analyses were employed. Migraine (n = 26) and muscle-contraction …

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Effects Of Artificial Mineral Licks On White-Tailed Deer., Stephen Redmore Schultz Jan 1990

Effects Of Artificial Mineral Licks On White-Tailed Deer., Stephen Redmore Schultz

LSU Historical Dissertations and Theses

A commercial mineral mixture for deer was used to evaluate the effects of broad-spectrum dietary mineral supplementation on white-tailed deer (Odocoileus virginianus) growth, antler development, and tissue mineral content. Forty-two artificial mineral licks for deer were established on 3 study areas in East Feliciana Parish, Louisiana. All licks were monitored monthly, recharged to original level if used, and mineral consumption recorded from May 1988 through December 1989. Consumption data were converted to estimated average per deer values based on population estimates. Effects of artificial lick mineral consumption on free-ranging deer were examined by comparing deer harvested during the 1988-89 and …

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A Geographic Information System For Risk Assessment Of Fasciola Hepatica In Cattle., Stanley Harland Zukowski Jan 1990

A Geographic Information System For Risk Assessment Of Fasciola Hepatica In Cattle., Stanley Harland Zukowski

LSU Historical Dissertations and Theses

A geographic information system (GIS) was used to assemble and analyze data on the spatial distribution of habitat of the snail, Fossaria bulimoides, an intermediate hose of Fasciola hepatica. A model of habitat was developed on a single 760ha farm on the Chenier Plain of southwestern Louisiana and extrapolated for testing on 12 other farms in a 29,000ha extended study area of the Chenier Plain region. Input maps were: (1) soil series (type), (2) fencelines, (3) F. bulimoides habitat, and (4) soil salinity. On the primary study farm, habitat was strongly associated with interfaces of marsh and chenier (relict beach) …

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Rice Improvement Through Tissue Culture: Inheritance Of Somaclonal Variation And Improvement Of Somaculture Techniques., Qingjun Xie Jan 1990

Rice Improvement Through Tissue Culture: Inheritance Of Somaclonal Variation And Improvement Of Somaculture Techniques., Qingjun Xie

LSU Historical Dissertations and Theses

The objectives of this research were to study the inheritance of homozygous variation from rice somaculture, to select rice somaclones for increased sheath blight resistance, and to determine the mode of inheritance of the resistance. To accomplish these objectives it was necessary to improve somaculture techniques for rice suspension and protoplast culture especially for the American long-grain cultivars. A method for incorporation of the chemical mutagen, ethyl methane-sulfonate (EMS), into the somaculture system was also developed to increase the frequency of somaclonal variation in tissue culture stable cultivars. The inheritance of six homozygous variant characteristics from five somaclones was investigated. …

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Effects Of Food Plots On Selected Growth Parameters, Productivity, And Harvesting Of White-Tailed Deer In A National Forest., Kenneth Dale Dancak Jan 1990

Effects Of Food Plots On Selected Growth Parameters, Productivity, And Harvesting Of White-Tailed Deer In A National Forest., Kenneth Dale Dancak

LSU Historical Dissertations and Theses

A total of 8.1 ha of warm-season and 16.8 ha of cool-season food plots were installed on 2 of 4 study units at National Red Dirt Wildlife Management Preserve, Louisiana, an area managed by the USDA Forest Service for multiple resources. Mean ($\pm$ s.e.) study unit size was 2220 $\pm$ 246 ha. No food plots were installed on the remaining 2 study units (controls). Warm-season food plots were planted with American jointvetch (Aeschynomene americana); cool-season plots were planted with red clover (Trifolium pratense), subterranean clover (Trifolium subterraneum), winter wheat (Triticum aestivum) and white clover (Trifolium repens). All plots were maintained …

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Genotypic And Phenotypic Adaptations Of The Southern Oyster Drills, Stramonita Canaliculata And S. Haemastoma Floridana To Salinity., Li-Lian Liu Jan 1990

Genotypic And Phenotypic Adaptations Of The Southern Oyster Drills, Stramonita Canaliculata And S. Haemastoma Floridana To Salinity., Li-Lian Liu

LSU Historical Dissertations and Theses

Environmental and genetic effects on salinity adaptation in the southern oyster drill were estimated by their salinity-related genotypic (i.e. determined by electrophoresis) and phenotypic (i.e. determined by salinity tolerance and microcalorimetry) variations. The systematics of Stramonita haemastoma were studied using allozyme, radular and shell characteristics to exclude taxonomic differences which might have obscured variations in salinity adaptation. Radular and shell features are not reliable as systematic characteristics. S. h. canaliculata and S. h. floridana are separable using allozyme characteristics. Nei's genetic distance (D = 0.28) and the fixed allelic differences in Fum, LeuAla, Mdh, and 6-Pgdh indicate that the differences …

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Specific Cell Adhesion And Its Application To Monitoring And Control Of Mixed Culture Bioreactors., Joseph William Roos Jan 1990

Specific Cell Adhesion And Its Application To Monitoring And Control Of Mixed Culture Bioreactors., Joseph William Roos

LSU Historical Dissertations and Theses

Specific cell adhesion was proposed as a means to separate and selectively remove or recycle a population in a mixed culture reactor. Theoretical analysis indicated that stable coexistence steady states of competitive mixed cultures and unstable recombinant cultures are possible with this method. Specific cell adhesion was used to separate populations of Escherichia coli based on their expression of maltoporin an outer membrane protein. This separation was possible due to maltoporin binding immobilized starch. Various methods for operating a packed bed of the immobilized starch support are reported. Operating conditions are identified that allow quantitative estimates of populations based on …

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"Her Excellence To Marre": The Problem Of Feminine Authority In Spenser's "Faerie Queene"., Mary Antonia Villeponteaux Jan 1990

"Her Excellence To Marre": The Problem Of Feminine Authority In Spenser's "Faerie Queene"., Mary Antonia Villeponteaux

LSU Historical Dissertations and Theses

Spenser has difficulty expressing an acceptable version of his queen's authority in The Faerie Queene. He must valorize her monarchy and its power, but his uneasiness about female political authority emerges throughout the text. Like the Petrarchan poet who fictionalizes his abject devotion to his lady while he also creates and so controls her through the same fiction, Spenser praises the queen's authority while at the same time he attempts to control it and contain it in the poem. This uneasy process is exemplified in the figure of Britomart: Spenser initially presents her as the near-perfect champion of Elizabeth's signature …

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A Comparative Study Of The Effects Of Sesbania Drummondii On The Hepatic Cytochrome P-450 Monooxygenase Systems Of Chickens And Rats., Marcy Iva Banton Jan 1990

A Comparative Study Of The Effects Of Sesbania Drummondii On The Hepatic Cytochrome P-450 Monooxygenase Systems Of Chickens And Rats., Marcy Iva Banton

LSU Historical Dissertations and Theses

The effect of an extract of Sesbania drummondii on the hepatic cytochrome P-450 monooxygenase system was evaluated in two experimental models, the White Leghorn chicken and the Sprague-Dawley rat. The cytochrome P-450 monooxygenase systems were compared using studies of catalytic activities and two major enzyme components, cytochrome P-450 and NADPH-cytochrome P-450 reductase. Two "classical" cytochrome P-450 inducers, phenobarbital and $\beta$-naphthoflavone, were used to probe induction mechanisms. S. drummondii induced opposite effects on the hepatic cytochrome P-450 component of chickens versus rats. Cytochrome P-450 specific content was increased 2-fold in chickens but decreased 2-fold in rats. Qualitative differences in microsomal proteins …

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Isolation And Physical Mapping Of The Mitochondrial Chromosome From The Zygomycete Mucor Racemosus., Mary Louise Schramke Jan 1990

Isolation And Physical Mapping Of The Mitochondrial Chromosome From The Zygomycete Mucor Racemosus., Mary Louise Schramke

LSU Historical Dissertations and Theses

Mitochondria were isolated from Mucor racemosus and DNA was purified from these organelles by cesium chloride/ethidium bromide isopycnic centrifugation. Examination of mitochondrial DNA samples with a transmission electron microscope revealed a circular mitochondrial chromosome approximately 63.8 kbp in length. Summation of restriction fragments of mitochondrial DNA separated by agarose gel electrophoresis yielded a comparable value of 63.4 kbp for the size of the intact molecule. Electrophoretic mobility and stoichiometry were determined for restriction fragments generated using nine different restriction enzymes. A physical map was deduced from single and double digestions of mitochondrial DNA with several of the restriction enzymes. The …

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The Narrative Creation Of Self In The Fiction By African-American And African-Caribbean Women Writers., Jerome P. De Romanet Jan 1990

The Narrative Creation Of Self In The Fiction By African-American And African-Caribbean Women Writers., Jerome P. De Romanet

LSU Historical Dissertations and Theses

This study entails an examination of the works of six authors (Maya Angelou, Audre Lorde, Paule Marshall, Toni Morrison, Gloria Naylor and Simone Schwarz-Bart) whose works are shaped by values and perceptions influenced by their experiences of sexual, racial and social marginalization. While I acknowledge differences in origin, beliefs and personality, I explore the common ground which unites them, and more specifically the complex ties that bind their individual "writing I" with their environment--"communitas," to use Victor Turner's term. This study is also an exploration of the modes in which these six writers create their idiosyncratic selves out of the …

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Habitat Use, Movements, And Behavior Of Shiny Cowbirds In Southwestern Puerto Rico., Paul Michael Mckenzie Jan 1990

Habitat Use, Movements, And Behavior Of Shiny Cowbirds In Southwestern Puerto Rico., Paul Michael Mckenzie

LSU Historical Dissertations and Theses

Shiny Cowbirds were primarily located in six major areas of concentration. Of these, all but one was in mesquite woodland. Overall, cowbirds used mesquite woodland almost 75% of the time but use of this habitat varied among weekly periods and was linked to rainfall received during weekly periods prior to the observation. Habitat use of cowbirds and the time they spent eating particular prey items were most correlated with total rainfall received 2-5 weeks prior to the observation (p =.0067 and p =.0149, respectively). Major food items taken by cowbirds following periods of sufficient rainfall were caterpillars, berries and grass …

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Effect Of Acid Rain And Humic Substances On Aluminum Toxicity (And); A Comparative Study Of Chemical Composition Of Old And Newly Deposited Plaque From Heart Patients., Jane Igoki Murungi Jan 1990

Effect Of Acid Rain And Humic Substances On Aluminum Toxicity (And); A Comparative Study Of Chemical Composition Of Old And Newly Deposited Plaque From Heart Patients., Jane Igoki Murungi

LSU Historical Dissertations and Theses

Effect of acid rain and humic acid on aluminum toxicity. A study was carried out to find if leaf extracts could be used to counteract the effect of acid rain and aluminum in soils and lakes. Tilapia, and common shiners fish, and alligator grass plant were used to study the effects of pH and aluminum. The effect of dried leaves on the pH and the buffering capacity of deionized water and the effect of the presence of cations such as iron, calcium and magnesium on aluminum toxicity were investigated. The results of our investigation indicated a synergistic toxic effect of …

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Spectroscopy Of Hexamethyldipyrromethene Anion: Interactions With Metal Ions., Cristian Oscar Franco Jan 1990

Spectroscopy Of Hexamethyldipyrromethene Anion: Interactions With Metal Ions., Cristian Oscar Franco

LSU Historical Dissertations and Theses

This work includes: (1) a search for charge transfer interaction involving hexamethyldipyrromethene (HL) as a donor; (2) a spectroscopic study of hexamethyldipyrromethene anion (L$\sp-$), and, (3) an investigation of the spectroscopic characteristic of the copper chelate CuL$\sb2$. There are presented reactions in which HL may react with some electron acceptors. It is reported that TCNE interacts with HL to form a 1:1 complex that has an equilibrium constant of (2.5 0.9) $\times$ 10$\sp{15}$. Spectroscopic results indicate that haloacetones also interact with HL. Hexamethyldipyrromethene is a molecule that consists of two methyl substituted pyrrole rings joined by means of a vinyl …

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Plant Allelochemicals And Insect Pathogens: The Effects Of Alpha-Tomatine On The Susceptibility Of Pseudoplusia Includens (Walker) And Heliothis Zea (Boddie) To The Entomogenous Fungus Nomuraea Rileyi (Farlow) Samson., Fernando Covas Gallardo Jan 1990

Plant Allelochemicals And Insect Pathogens: The Effects Of Alpha-Tomatine On The Susceptibility Of Pseudoplusia Includens (Walker) And Heliothis Zea (Boddie) To The Entomogenous Fungus Nomuraea Rileyi (Farlow) Samson., Fernando Covas Gallardo

LSU Historical Dissertations and Theses

Research was conducted to determine the impact of the allelochemical, $\alpha$-tomatine, on the susceptibility of the lepidopterous pests, Heliothis zea (Boddie) and Pseudoplusia includens (Walker) to the entomogenous fungus, Nomuraea rileyi (Farlow) Samson. In one experiment, $\alpha$-tomatine inhibited colony formation and growth of N. rileyi, in vitro. In vivo, larval growth and developmental time of H. zea were affected by $\alpha$-tomatine and N. rileyi. The fungus was detected in the hemolymph and tissue of larvae treated with two concentrations (LC$\sb{50}$ and LC$\sb{90}$) of N. rileyi conidia, including those fed $\alpha$-tomatine. At the LC$\sb{50}$, $\alpha$-tomatine protected larvae against N. rileyi and …

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The Incidence Of Vibrio Species In Louisiana And Maryland Oysters (Crassostrea Virginica)., Mary Lynelle Ford Jan 1990

The Incidence Of Vibrio Species In Louisiana And Maryland Oysters (Crassostrea Virginica)., Mary Lynelle Ford

LSU Historical Dissertations and Theses

Vibrio species, normal inhabitants of the sea and of shellfish harvested from marine or brackish waters, have been established as the causative agents of serious human infections. An investigation to isolate and identity Vibrio species in oysters collected from eight Louisiana commercial oyster beds was conducted. A selection of 127 vibrio isolates and 46 reference strains, including all known Vibrio species, were subjected to a bacteriological identification scheme of 46 parameters. When the data from the wild strains and the reference strains were analyzed by the numerical taxonomy program, TAXAN Version 3.0, six major phena were evident. Four of the …

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Biochemical Characterization And Gene Mapping Of The Channel Catfish Herpesvirus (Ccv)-Encoded Thymidine Kinase, A Selectable Site For Homologous Recombination., Larry Allen Hanson Jan 1990

Biochemical Characterization And Gene Mapping Of The Channel Catfish Herpesvirus (Ccv)-Encoded Thymidine Kinase, A Selectable Site For Homologous Recombination., Larry Allen Hanson

LSU Historical Dissertations and Theses

The channel catfish herpesvirus (CCV) encodes a thymidine kinase (Tk) which is biochemically distinguishable from it's host, the channel catfish ovary (CCO), and other herpesvirus Tk's. Tk deficient CCO cells (CCOBr) were developed by propagating CCO cells in increasing concentrations of 5-bromo-2$\sp\prime$-deoxyuridine (BUdR). CCV infection produced high Tk activity in these Tk deficient cells. This activity was compared to CCO-Tk in ATP and CTP phosphate donor assays, nucleoside substrate-competition and dTTP feedback inhibition assays. The viral Tk was more competitively inhibited by deoxypurines than cellular Tk and showed less dTTP mediated feedback inhibition. CCO-Tk utilized lower concentrations of ATP more …

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The Use Of Cell Culture Systems To Improve Bovine Embryo Viability In Vitro., Stephen Harry Pool Jan 1990

The Use Of Cell Culture Systems To Improve Bovine Embryo Viability In Vitro., Stephen Harry Pool

LSU Historical Dissertations and Theses

Growth characteristics for fetal bovine uterine fibroblast cells (FBUFC) and frozen-thawed bovine (b) and caprine (g) trophoblastic vesicles (TV) were similar in (A) Ham's F-10 (HF-10), (B) MEM (with Earle's salts), (C) RPMI-1640 and (D) Menezo's B$\sb2$ (B$\sb2$), each supplemented with 10% FCS and Ab-Am (Experiment (Exp) I). Cell numbers declined initially but increased linearly thereafter for 5 days. The bTV and gTV that survived freezing had similar viability across time and Treatments (Trt). Exp II compared the (A) bTV, (B) FBUFC monolayer and (C) bTV-monolayer co-culture systems to (D) HF-10 alone for culture of 8- to 32-cell bovine embryos. …

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Louisiana Barrier Island Change Analysis Derived From A Geographic Information System (Gis) Based On Sequential Aerial Photography., Lionel Dorsey Worthy Jr Jan 1990

Louisiana Barrier Island Change Analysis Derived From A Geographic Information System (Gis) Based On Sequential Aerial Photography., Lionel Dorsey Worthy Jr

LSU Historical Dissertations and Theses

Surface feature maps were derived from color-infrared aerial photographs for Louisiana's Timbalier Island and Eastern Isles Dernieres. These provided a basis for the implementation of a barrier island Geographic Information System (GIS), a quantitative spatial framework through which specific proximal and temporal interactions could be examined. This system was utilized to observe relationships between changes in island shorelines and surface areas relative to location and extent of island cover categories. It was further employed to test the applicability of the rollover and deltaic barrier cycle models of island dynamics within the context of the Louisiana coastal environment. Both islands exhibited …

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Synthetic Peptide Analyses Of The Surface Glycoproteins Of Equine Infectious Anemia Virus., Judith Marchand Ball Jan 1990

Synthetic Peptide Analyses Of The Surface Glycoproteins Of Equine Infectious Anemia Virus., Judith Marchand Ball

LSU Historical Dissertations and Theses

Previous investigations have characterized both the genomic and antigenic variations in equine infectious anemia virus (EIAV) surface glycoproteins that arise during replication of the virus. DNA sequence analyses have defined regions of conserved and variable sequences localized in the EIAV envelope glycoproteins. These studies indicate that EIAV persistence and periodicity of clinical disease result from the relatively rapid evolution of antigenic variants which allows the virus to temporarily circumvent the host immune response. The primary objective of this work is the complete characterization of the immunogenic components of the EIAV env-encoded surface unit (SU) and transmembrane (TM) glycoproteins. These surface …

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The Effect Of Olivocochlear Bundle Transection On Cochlear Mechanics., Thomas Allen Littman Jan 1990

The Effect Of Olivocochlear Bundle Transection On Cochlear Mechanics., Thomas Allen Littman

LSU Historical Dissertations and Theses

A growing body of research suggests that the efferent innervation to the cochlea, the olivocochlear bundle, plays a role in modulating the mechanical function of the cochlea. Some of the more provocative findings supporting an hypothesis of OCB modulation have come from studies which assessed efferent influences on tuning curves and acoustic distortion products, two measures thought to be sensitive indicators of cochlear mechanical function. While the OCB appears to be capable of modifying cochlear mechanics, the functional role attributed to the efferents has been difficult to define. For example, some studies which have transected all or part of the …

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Identification Of Vibrio Anguillarum And Vibrio Ordalii By A Monoclonal Antibody Coagglutination Assay., Zhongshi Wang Jan 1990

Identification Of Vibrio Anguillarum And Vibrio Ordalii By A Monoclonal Antibody Coagglutination Assay., Zhongshi Wang

LSU Historical Dissertations and Theses

Vibrio anguillarum exhibits species-specific antigens on the protein core of the polar flagellum (H) and H-determinants which are expressed by heterologous Vibrio species. Monoclonal antibody (MAb) which reacted with flagella core protein by ELISA were affinity purified from protein A-sepharose. Staphylococcus aureus Cowan 1 cells armed with anti-H MAb coagglutinated each of the 10 V. anguillarum O-antigen serovars within 1 to 2 minutes, as well as V. ordalii isolates. These findings suggest these two vibrios express similar if not identical species-specific H-determinants. The anti-H reagent did not coagglutinate 20 heterologous Vibrio species. MAb generated against LPS, extracted from V. anguillarum …

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Wood Specific Gravity Gradients In Tropical Trees., Michael Carl Wiemann Jan 1990

Wood Specific Gravity Gradients In Tropical Trees., Michael Carl Wiemann

LSU Historical Dissertations and Theses

Pith to bark wood specific gravity (SG) trends were measured in tropical trees and compared with trends found in temperate trees. Extraordinary increases were found across the stems of some tropical wet forest colonizing species, with most tropical species showing at least moderate increases. In contrast, temperate species showed little change, and decreases were almost as common as increases. In Chapter One (published in Wood Fiber Sci. 20(3):344-349), three colonizing species in tropical wet forest were found to produce low SG wood when small and to linearly increase SG with diameter growth. Trends in small trees were similar to those …

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Molecular Cloning And Characterization Of The Rhodobacter Capsulatushema Gene., Maureen Smith Wright Jan 1990

Molecular Cloning And Characterization Of The Rhodobacter Capsulatushema Gene., Maureen Smith Wright

LSU Historical Dissertations and Theses

The first step in the common tetrapyrrole pathway in Rhodobacter capsulatus is the condensation of glycine with succinyl CoA to form 5-aminolevulinate which is then used in the synthesis of bacteriochlorophyll, heme, vitamin B-12, and siroheme. To isolate mutants unable to form 5-aminolevulinate, as a first step in studying regulation of the tetrapyrrole pathway, R. capsulatus was mated with E. coli carrying plasmid pSUP2021. pSUP2021 carries transposon Tn5 and is incapable of replicating in R. capsulatus making it an ideal vector for transposon mutagenesis. One colony was found which requires 5-aminolevulinate for growth. This mutant strain, designated AJB529, has a …

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