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Application Of A Tetrazolium Salt With A Water-Soluble Formazan As An Indicator Of Viability In Respiring Bacteria, P. Roslev, G. M. King Jan 1993

Application Of A Tetrazolium Salt With A Water-Soluble Formazan As An Indicator Of Viability In Respiring Bacteria, P. Roslev, G. M. King

Faculty Publications

The tetrazolium salt sodium 3'-{1-[(phenylamino)-carbonyl]-3,4- tetrazolium}-bis (4-methoxy-6-nitro)benzene-sulfonic acid hydrate (XTT) was examined for use as a colorimetric indicator of viability in respiring bacteria. XTT was reduced to an orange, water-soluble formazan product by Methylosinus trichosporium OB3b, Pseudomonas putida, Escherichia coli, and Bacillus subtilis. Formazan production was proportional to live cell biomass, and XTT was reduced by all cultures in the absence of added electron-coupling agents. XTT reduction by M. trichosporium OB3b was linear over several hours and was stimulated by the presence of an exogenous substrate (methanol). Addition of cyanide to cultures incubated under oxic conditions gave an initial 10-fold …

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Glycine And Alanine Supplementation Of Culture Medium Enhances Development Of In Vitro Matured And Fertilized Cattle Embryos, K. Moore, K. R. Bondioli Jan 1993

Glycine And Alanine Supplementation Of Culture Medium Enhances Development Of In Vitro Matured And Fertilized Cattle Embryos, K. Moore, K. R. Bondioli

Faculty Publications

One-cell cattle embryos were prepared by in vitro oocyte maturation and fertilization (IVM/IVF) and cultured with or without oviductal cells. Embryos were evaluated after 7 days in culture to determine the percentage developing from the 1-cell stage to the morula or blastocyst stage. The combination of glycine (2 mM) and alanine (1 mM) with oviductal cells (experiment 1) improved embryo development over that in control culture (29 vs. 13%; p < 0.05). An optimum response was obtained with 10 mM glycine and 1 mM alanine in coculture (experiments 2 and 3). In experiment 4, the effects of glycine (0 or 10 mM), alanine (0 or 1 mM), and the presence or absence of oviductal cells were tested. In the absence of oviductal cells, the addition of glycine, alanine, or glycine and alanine combined improved embryonic development over that in control medium (45, 33, 42 vs. 24%, p < 0.001, p < 0.05, p < 0.001, respectively). However, the effect of the combination of glycine and alanine was not different from that of glycine alone when oviductal cells were absent (42 vs. 45%, p > 0.10). In the presence of oviductal cells, glycine or the combination of glycine and alanine improved embryonic development over that in the control medium with cells (47, 55 vs. 37%, …

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Embryo Cloning In Cattle: The Use Of In Vitro Matured Oocytes, F. Barnes, M. Endebrock, C. Looney, R. Powell, M. Westhusin, K. Bondioli Jan 1993

Embryo Cloning In Cattle: The Use Of In Vitro Matured Oocytes, F. Barnes, M. Endebrock, C. Looney, R. Powell, M. Westhusin, K. Bondioli

Faculty Publications

In vitro matured (IVM) bovine oocytes were examined to determine their potential viability in embryo cloning. Activation competence, as monitored by pronuclear formation, increased with oocyte age. Oocytes readily formed a pronucleus when challenged with an electrical pulse 30 h after the onset of maturation. Developmental competence of IVM oocytes tended to increase with oocyte age (P= 0.079). Selection of IVM oocytes on the basis of the presence of a polar body 24 h after the onset of maturation and the size of the follicle from which the oocyte was derived improved development of nuclear transfer embryos (polar body positive …

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Response Of Early Lactation Cows To Fat Supplementation In Diets With Different Nonstructural Carbohydrate Concentrations, James C. Coomer, Henry E. Amos, Cathy C. Williams, Jeffrey G. Wheeler Jan 1993

Response Of Early Lactation Cows To Fat Supplementation In Diets With Different Nonstructural Carbohydrate Concentrations, James C. Coomer, Henry E. Amos, Cathy C. Williams, Jeffrey G. Wheeler

Faculty Publications

Twenty-four high producing (36.7 kg/d, initially) Holstein cows in early lactation were used in a 63-d lactation trial to study the effects of low (28%), medium (31%). and high (37%) nonstructural carbohydrate concentrations in diets with added fat. Diets with isonitrogenous (17% CP) and fed as TMR with 41% sorghum silage. Nonstructural carbohydrate concentrations were altered by substitution of corn gluten feed and soybean hulls (50:50) for wheat and corn in the concentrate portion of the diet. Fat was added at 3% of DM in the form of yellow grease. Production of milk (38.5, 38.9, and 40.4 kg/d) and 3.5% …

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Response Of Early Lactation Cows To Fat Supplementation In Diets With Different Nonstructural Carbohydrate Concentrations, James C. Coomer, Henry E. Amos, Cathy C. Williams, Jeffrey G. Wheeler Jan 1993

Response Of Early Lactation Cows To Fat Supplementation In Diets With Different Nonstructural Carbohydrate Concentrations, James C. Coomer, Henry E. Amos, Cathy C. Williams, Jeffrey G. Wheeler

Faculty Publications

Twenty-four high producing (36.7 kg/d, initially) Holstein cows in early lactation were used in a 63-d lactation trial to study the effects of low (28%), medium (31%). and high (37%) nonstructural carbohydrate concentrations in diets with added fat. Diets with isonitrogenous (17% CP) and fed as TMR with 41% sorghum silage. Nonstructural carbohydrate concentrations were altered by substitution of corn gluten feed and soybean hulls (50:50) for wheat and corn in the concentrate portion of the diet. Fat was added at 3% of DM in the form of yellow grease. Production of milk (38.5, 38.9, and 40.4 kg/d) and 3.5% …

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Localization And Nucleotide Sequences Of Genes Mediating Site-Specific Recombination Of The Slp1 Element In Streptomyces Lividans, M. A. Brasch, G. S. Pettis, S. C. Lee, S. N. Cohen Jan 1993

Localization And Nucleotide Sequences Of Genes Mediating Site-Specific Recombination Of The Slp1 Element In Streptomyces Lividans, M. A. Brasch, G. S. Pettis, S. C. Lee, S. N. Cohen

Faculty Publications

SLP1 is a 17.2-kbp genetic element indigenous to the Streptomyces coelicolor chromosome. During conjugation, SLP1 can undergo excision and subsequent site-specific integration into the chromosomes of recipient cells. We report here the localization, nucleotide sequences, and initial characterization of the genes mediating these recombination events. A region of SLP1 adjacent to the previously identified site of integration, attP, was found to be sufficient to promote site-specific integration of an unrelated Streptomyces plasmid. Nucleotide sequence analysis of a 2.2-kb segment of this region reveals two open reading frames that are adjacent to and transcribed toward the attP site. One of these, …

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Race, Income, And Survival From Breast Cancer At Two Public Hospitals, David Ansell, Steven Whitman, Rebecca Lipton, Richard Cooper Jan 1993

Race, Income, And Survival From Breast Cancer At Two Public Hospitals, David Ansell, Steven Whitman, Rebecca Lipton, Richard Cooper

Faculty Publications

Background. Some studies have shown that adjustment for socioeconomic status reduces breast cancer survival differences between blacks and whites. The purpose of this study is to evaluate the effect of age, race, stage, treatment, and income status on breast cancer survival among women attending public hospitals in Chicago, Illinois. Methods. Hospital Cancer Registry data on 887 black women and 265 white women with breast cancer onset between 1973–1985 were analyzed using Cox regression and Kaplan–Meier techniques. The purpose was to examine the effect of age, race, stage, treatment, and income on breast cancer survival. Results. Black women with breast cancer …

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Louisiana Agriculture Magazine, Winter 1993, Lsu Agricultural Experiment Station Jan 1993

Louisiana Agriculture Magazine, Winter 1993, Lsu Agricultural Experiment Station

Louisiana Agriculture

No abstract provided.

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A Criterion Validity Study Of The Schizophrenia Subscale Of The Pimra., Naomi Arffa Swiezy Jan 1993

A Criterion Validity Study Of The Schizophrenia Subscale Of The Pimra., Naomi Arffa Swiezy

LSU Historical Dissertations and Theses

Sixty-five mildly to moderately mentally retarded adult patients from institutional and community placements in Louisiana and Texas and with a diagnosis of schizophrenia, depression, or no psychopathology were recruited. The primary goal of the study was to establish the validity of the schizophrenia subscale of the PIMRA for diagnosing schizophrenia among mentally retarded individuals. The same methods utilized to determine the validity of the schizophrenia subscale were also used to replicate the validation of the depression subscale of the PIMRA. In addition, the extent to which other PIMRA subscale scores aid in diagnosis was investigated. Assessment measures included the informant …

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Methodological Content And Teaching Delivery Used By Vocational Teacher Education Faculty In University Council And Other Selected Higher Education Institutions., Robert Barry Blair Jan 1993

Methodological Content And Teaching Delivery Used By Vocational Teacher Education Faculty In University Council And Other Selected Higher Education Institutions., Robert Barry Blair

LSU Historical Dissertations and Theses

The purpose of this study was to identify the methodological content and teaching delivery used by vocational teacher education faculty in University Council for Vocational Education (UCVE) institutions and other selected higher education institutions (NON-UCVE). The population for this study was defined as: full-time vocational teacher education faculty in programs at Research I, Research II, and Doctorate Granting Colleges and Universities I where comprehensive vocational education programs were offered. Administrative leaders for each institution identified the vocational teacher education faculty which established the frame for the study. A stratified-random cluster sample of vocational teacher educators from UCVE institutions and NON-UCVE …

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In Vitro Studies On The Interactions Between Toxoplasma Gondii And Its Host Cell., Sandra Karen Halonen Jan 1993

In Vitro Studies On The Interactions Between Toxoplasma Gondii And Its Host Cell., Sandra Karen Halonen

LSU Historical Dissertations and Theses

Toxoplasma gondii is an obligate intracellular protozoan parasite of the Phylum Apicomplexa. The parasite resides in the cytoplasm of its host cells in a membrane bound compartment called the parasitophorous vacuole. All growth and development of the parasite occur within this compartment. In this thesis, the interactions between the Vero cells, a fibroblast-like cell line, and the parasite which occur during the intracellular growth of the parasite were addressed. The impact of infection on the host cell intermediate filaments and microtubular cytoskeletal elements was examined by immunofluorescence microscopy. Host cell intermediate filaments were found to overcoat the parasite vacuole beginning …

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Hydrologic Modelling With A Spatial Database., Richard Gilbert Greene Jan 1993

Hydrologic Modelling With A Spatial Database., Richard Gilbert Greene

LSU Historical Dissertations and Theses

Hydrologic modelling can be enhanced and improved through the utilization of a Geographic Information System (GIS). Information can be stored and analyzed by the tools available within a GIS to create a spatial database that realistically represents a watershed for hydrologic modelling. This study presents an approach whereby the data available in the GIS determine the modelling strategy. The soil, topography and land cover data for the watershed were analyzed with the spatial analysis tools of a GIS to determine the hydrologic response areas. The coordinate values that define the locations and boundaries of features in the GIS were used …

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Foliar Fungicides For Use In The Management Of Rice Diseases, D E. Groth Jan 1993

Foliar Fungicides For Use In The Management Of Rice Diseases, D E. Groth

LSU Agricultural Experiment Station Reports

No abstract provided.

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Relationship Between Vegetation And Soil Formation In A Rapidly Submerging Coastal Marsh, J. A. Nyman, R. D. Delaune, H. H. Roberts, W. H. Patrick Jan 1993

Relationship Between Vegetation And Soil Formation In A Rapidly Submerging Coastal Marsh, J. A. Nyman, R. D. Delaune, H. H. Roberts, W. H. Patrick

Faculty Publications

In a Terrebonne Basin (Louisiana) marsh, Cs dating indicated that vertical accretion (0.98cm yr ) was extremely rapid relative to other marshes, but insufficient to counter submergence (1.38cm yr ). Mineral and organic matter accumulation were similar to that in other marshes. This marsh is threatened by a positive feedback loop of plant flooding stress and inadequate vertical accretion. Inadequate plant growth limits vertical accretion, which further increases flooding and decreases plant production. Thus plant production partly determines the degree of submergence some coastal and estuarine marshes will tolerate. -from Authors 137 -1 -1

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Investigations Into Methods For The Extraction And Detection Of Chlorinated Pesticides In Aquatic Animals., Heidi Marie Lott Jan 1993

Investigations Into Methods For The Extraction And Detection Of Chlorinated Pesticides In Aquatic Animals., Heidi Marie Lott

LSU Historical Dissertations and Theses

Methodologies for the extraction and analysis of chlorinated pesticides from aquatic species are reviewed and compared. New multiresidue isolation techniques using Matrix Solid Phase Dispersion (MSPD) are presented for the extraction and subsequent gas chromatographic, electron capture detector determination of 14 chlorinated pesticides ($\alpha$-BHC, $\beta$-BHC, lindane, heptachlor, aldrin, heptachlor epoxide, p,p$\sp\prime$-DDE, dieldrin, endrin, 4,4$\sp\prime$-DDD, endrin aldehyde, p,p$\sp\prime$-DDT, endosulfan sulfate, and methoxychlor) from crayfish (Procambarus clarkii) hepatopancreas, oysters (Crassostrea virginica) and fish muscle tissues. Pureed crayfish hepatopancreata or oysters or fish muscle fillets (0.5-g aliquots) were fortified with the 14 pesticides, plus $\delta$-BHC as an internal standard, before being blended with …

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Immunologic And Pathologic Responses Of Macaca Mulatta Experimentally Infected With Simian Immunodeficiency Virus And Campylobacter Jejuni., Robert Wayne Kornegay Jan 1993

Immunologic And Pathologic Responses Of Macaca Mulatta Experimentally Infected With Simian Immunodeficiency Virus And Campylobacter Jejuni., Robert Wayne Kornegay

LSU Historical Dissertations and Theses

Five Macaca mulatta were infected with SIV/DELTA$\sb{\rm B670}.$ Approximately 70 days later, this group (SIV) and five age, sex, weight matched not SIV-infected (NEG) M. mulatta were inoculated orally with approximately $3\times10\sp{10}$ Campylobacter jejuni. Small and large bowel mucosal biopsies, bowel contents, sera, blood, and rectal swabs were collected before and after C. jejuni inoculation. Biopsy cryosections were stained with histologic stains and immunocytochemically for lymphocyte subsets, plasmacytes, macrophages, and B-cells. Coded stained sections were examined semiquantitatively or quantitatively using computerized image analysis. Circulating lymphocyte subsets were determined using FACS analysis. Campylobacter jejuni was recultured from 4/5 SIV and 4/5 …

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The Interrelationships Of Rotylenchulus Reniformis Linford And Oliveira With Rhizoctonia Solani Kuhn On Cotton., Ambalavanan Sankaralingam Jan 1993

The Interrelationships Of Rotylenchulus Reniformis Linford And Oliveira With Rhizoctonia Solani Kuhn On Cotton., Ambalavanan Sankaralingam

LSU Historical Dissertations and Theses

The interrelationships between the reniform nematode, Rotylenchulus reniformis Linford and Oliveira, and the fungus Rhizoctonia solani Kuhn were studied on cotton (Gossypium hirsutum L.). Parasitism of cotton seedlings by R. solani resulted in enhanced reproduction of R. reniformis. In the presence of the fungus, there was increased egg production by the nematode which resulted in augmented soil population density. Enhanced reproduction of the nematode in the presence of the fungus was consistent across isolates of R. solani, populations and inoculum levels of R. reniformis, and cotton cultivars. The nematode did not influence the severity of seedling blight disease. At 90 …

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A Blackboard Integration Of Manufacturing Databases Using An Intelligent Interface., David Anderson Koonce Jan 1993

A Blackboard Integration Of Manufacturing Databases Using An Intelligent Interface., David Anderson Koonce

LSU Historical Dissertations and Theses

The explosion of computer applications into the world of manufacturing along functional lines has produced the often mentioned "islands of automation." Although many issues and problems are involved in interfacing and integrating the databases that serve these applications, we can extract valuable data from these independent systems to provide important information to decision makers. This research resulted in the development of MIMIR (Multiple Integrated Manufacturing Information Resources), a decision support system based upon the blackboard architecture. The blackboard architecture extends the common expert system design to include multiple expert systems, termed Knowledge Sources (KS's), which combine to solve problems too …

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Remagnetization Of Carbonates In The Appalachian Basin., Barbara Saffer Jan 1993

Remagnetization Of Carbonates In The Appalachian Basin., Barbara Saffer

LSU Historical Dissertations and Theses

Paleomagnetic and rock magnetic data from two transects of southern and northern Appalachian Basin carbonates demonstrate different patterns of Late Paleozoic remagnetization and magnetite concentration. Samples were collected in Ordovician and Mississippian carbonates of Tennessee and Alabama and in Devonian carbonates of New York and Ontario. In the southern basin, Paleozoic carbonates of the Nashville Dome and of the fold-thrust belt near Chattanooga were remagnetized during the Late Paleozoic Kiaman period. These remagnetized carbonates contain more magnetite than do unremagnetized carbonates in the intervening basin. The unremagnetized carbonates demonstrate only a present field magnetization except for one Mississippian site in …

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The Absent Father In Modern Drama., Paul Nagim Rosefeldt Jan 1993

The Absent Father In Modern Drama., Paul Nagim Rosefeldt

LSU Historical Dissertations and Theses

Theories of modern drama point out the powerful sense of loss and alienation that is woven into the very fabric of modern drama. This sense of loss is connected with the death of God and the destruction of absolute value systems. This study, however, takes the theory of loss one step further, tying the absence of God in modern drama to the absence of the father. The psychoanalytical theories of Sigmund Freud, Jacques Lacan, and Carl Jung view the father as a disembodied presence standing above and outside of culture. These psychological theories of the father can be connected to …

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Daily Stress And Smoking., Kathryn Leigh Nathan Jan 1993

Daily Stress And Smoking., Kathryn Leigh Nathan

LSU Historical Dissertations and Theses

This study examined daily minor stress and cigarette smoking in adult habitual smokers. In this study, 55 subjects monitored daily stress, daily state anxiety, and daily cigarette intake for 21 consecutive days. Subjects also completed measures of trait anxiety, self-reported smoking motives, recent major life events, and social support. These variables, along with gender, were used to predict associations between daily cigarette intake and scores on daily stress and anxiety inventories. Results of within- and between-subjects time series correlational analyses showed significant associations between scores on measures of daily stress and daily cigarette intake. While subjects as individuals showed marked …

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Dual Diagnosis In Persons With Severe Or Profound Mental Retardation: A Reliability Study Of The Dash., Jay Anthony Sevin Jan 1993

Dual Diagnosis In Persons With Severe Or Profound Mental Retardation: A Reliability Study Of The Dash., Jay Anthony Sevin

LSU Historical Dissertations and Theses

The present study was designed to extend the literature on assessing psychopathology in persons with mental retardation. The primary goal of the study was to evaluate the psychometric properties of the Diagnostic Assessment for the Severely Handicapped (DASH), focusing on reliability issues. A secondary goal was to examine the prevalence of psychopathology and behavior problems in the severely handicapped. Subjects included 658 institutionalized adults with severe or profound mental retardation. Adequate reliability of DASH items and subscales, with a few notable exceptions, was obtained. Prevalence rates of various behavior disorders and symptoms of mental illness are presented. Practical implications of …

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The Genetic Effects Of Forest Fragmentation On Amazonian Forest Birds., John Marshall Bates Jan 1993

The Genetic Effects Of Forest Fragmentation On Amazonian Forest Birds., John Marshall Bates

LSU Historical Dissertations and Theses

I present allozyme and mitochondrial DNA (mtDNA) data on the genetic structure of five species of Amazonian forest birds at two geographic scales. The five species, Glyphorynchus spirurus (family Dendrocolaptidae), Leptopogon amaurocephalus (Tyrannidae), Hypocnemis cantator, Myrmeciza hemimelaena, and Hylophylax poecilinota (all three Formicariidae), are common forest understory inhabitants throughout much of Amazonia. At the local geographic scale, I hypothesized that forest fragmentation affected genetic structure in these species. Study sites were in the Department of Santa Cruz, Bolivia. Six sites separated by 150 km or less for each species were sampled: three sites in continuous Amazonian forest, and three in …

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Mimesis And Poiesis In The Novel: William Faulkner's "Go Down, Moses" And The Mythopoeic Turn In The American Imagination., Paul Richard Connell Jan 1993

Mimesis And Poiesis In The Novel: William Faulkner's "Go Down, Moses" And The Mythopoeic Turn In The American Imagination., Paul Richard Connell

LSU Historical Dissertations and Theses

In the course of its development as a genre, the novel shifted in the mid-twentieth century from a mimetic model grounded in imitation and colored with pessimism, to a poietic one based on discovery and novelty and foregrounded in hope. Precipitated by a crisis in representation after Joyce, the novel found in its own history, through the recuperation of older literary forms, new possibilities of representation, and shifted away from assumptions based on fact and history, to one grounded in miracle and myth. This shift was anticipated by the theories of the German Romantics Schlegel and Novalis and is adumbrated …

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Structural Analysis And Methionine Ehancement Of The Bean Seed Storage Protein Phaseolin., John M. Dyer Jan 1993

Structural Analysis And Methionine Ehancement Of The Bean Seed Storage Protein Phaseolin., John M. Dyer

LSU Historical Dissertations and Theses

Common beans are widely utilized as a food source, yet are limited as a complete source of protein due to low levels of methionine, an essential amino acid for humans. A protein engineering strategy was developed to increase the methionine content of phaseolin, the primary seed storage protein in common beans. The engineering strategy consists of three major parts. In the first part, a set of biophysical probes was developed to characterize the stability of wild-type and modified phaseolin proteins. I used absorbance, fluorescence emission, circular dichroism, and fluorescence polarization anisotropy to monitor phaseolin denaturation induced by urea, guanidinium chloride, …

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Depressive Symptoms In Prepubertal Children., Lesley Stabinsky Compton Jan 1993

Depressive Symptoms In Prepubertal Children., Lesley Stabinsky Compton

LSU Historical Dissertations and Theses

This study was designed: (1) to explore interinformant reliability between preadolescent students, their teachers, and their parents; (2) to investigate the use of standardized and non-standardized academic variables as predictors of depression; and (3) to assess differences in depression between black and white students. One hundred and twenty, fourth and fifth grade students and teachers participated. Sixty-eight parents also volunteered for this study. The Child Depression Inventory and the modified Bellevue Index of Depression were administered to students, teachers, and parents. Significant but moderate interinformant reliability was found between teachers and students and between teachers and parents on both assessment …

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Functional Morphology Of The Lingual Apparatus Of Sandgrouse (Aves: Pteroclidae)., Werner Muller Jan 1993

Functional Morphology Of The Lingual Apparatus Of Sandgrouse (Aves: Pteroclidae)., Werner Muller

LSU Historical Dissertations and Theses

The morphology of the lingual apparatus of three species of sandgrouse (Aves; Pteroclidae) has been described. All biomechanically important parts were included in the description, i.e., all muscles potentially involved in the functioning of the lingual apparatus, all skeletal parts, the salivary glands associated with the lingual apparatus, and the surface morphology of the oropharyngeal cavity. For each muscle its potential functions have been described. In a comparison with data from the literature of three other groups of birds it was found that the functional organization of the lingual apparatus of the sandgrouse is strikingly similar to the one found …

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Psychosocial Co-Factors And Hiv Disease Status., Bradley Thomas Thomason Jan 1993

Psychosocial Co-Factors And Hiv Disease Status., Bradley Thomas Thomason

LSU Historical Dissertations and Theses

Concern over the devastating effects of the Human Immunodeficiency Virus (HIV) has been met with rigorous research efforts by allied health professions. Identifying variables, or co-factors, that contribute to the progression of HIV has been of increased interest to health professionals in recent years. Social scientists as well as medical professionals have begun to offer evidence that certain psychosocial co-factors are important in predicting the health status of HIV-positive individuals. A few models have been offered to illustrate the interrelations among psychosocial co-factors and HIV disease. Stress, social support, coping, and mood states constitute the most frequently researched variables in …

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Sulfadimethoxine Analysis In Channel Catfish: A Model Drug Residue Monitoring Program For Aquaculture., Calvin Charles Walker Jan 1993

Sulfadimethoxine Analysis In Channel Catfish: A Model Drug Residue Monitoring Program For Aquaculture., Calvin Charles Walker

LSU Historical Dissertations and Theses

Analytical methods for extraction, detection, and quantitation of sulfadimethoxine (SDM) residues in channel catfish muscle and plasma were developed for a tiered residue monitoring program. The plasma and muscle concentrations of SDM and its primary metabolite in channel catfish, 4-N-acetylsulfadimethoxine (N-acetyl SDM), were determined in SDM medicated fish. Drug extraction methods using matrix solid phase dispersion (MSPD), drug screening methods using enzyme-linked immunoassay (ELISA), and drug residue quantitation methods using high pressure liquid chromatography (LC) are presented. All methods were developed for the simultaneous extraction and analysis of the parent compound and metabolite. MSPD extracts of muscle or plasma were …

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Seed Dormancy In Red Rice (Oryza Sativa): Changes In Embryo Ph And Metabolism During The Dormancy-Breaking Process., Steven Footitt Jan 1993

Seed Dormancy In Red Rice (Oryza Sativa): Changes In Embryo Ph And Metabolism During The Dormancy-Breaking Process., Steven Footitt

LSU Historical Dissertations and Theses

Hydrated, dehulled, dormant seeds of red rice (Oryza sativa L.) were exposed to chemical treatments (nitrite, propionic acid, methyl propionate, propionaldehyde, and n-propanol) that saturate the dormancy-breaking response. Dormancy-breaking chemicals were (a) metabolized (n-propanol and propionate) by embryos in dormant seeds to weak acids; (b) decreased embryo pH; and (c) increased embryo (Fru 2,6-P$\sb2$) prior to dormancy-breaking. Embryo acidification, but not increased embryo (Fru 2,6-P$\sb2$), was associated with the chemical contact interval required for the onset of dormancy-breaking. During chemical contact, embryo (Fru 2,6-P$\sb2$) increased independent of dormancy-breaking and was inversely correlated with the elapsed time to 30% germination. On …

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