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Involvement Of Interleukin 2 Receptors In Conceptus-Derived Suppression Of T And B Cell Proliferation In Horses, T. L. Roth, K. L. White, D. L. Thompson, S. Rahmanian, D. W. Horohov Jan 1992

Involvement Of Interleukin 2 Receptors In Conceptus-Derived Suppression Of T And B Cell Proliferation In Horses, T. L. Roth, K. L. White, D. L. Thompson, S. Rahmanian, D. W. Horohov

Faculty Publications

The mechanism by which a horse conceptus-derived immunosuppressive factor (HCS) of M(r) >100 000 inhibits lymphocyte proliferation was investigated. The factor was obtained from the culture supernatants of 20-day-old horse conceptuses; activity, identified by reduced uptake of [3H]thymidine by mitogen-stimulated lymphocytes, was greatest (P0.05). Data from a fluorescence-activated cell sorter indicated that supplementation with HCS reduced the number of T cells in phytohaemagglutinin-stimulated cultures and suppressed proliferation of T and B cells in pokeweed-mitogen-stimulated cultures compared with controls. Cell proliferation was greater (P0.05) from that of control cells. The addition of stimulated equine lymphocyte supernatant to cultures supplemented with HCS …

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Structure And Light-Induced Expression Of A Small Heat-Shock Protein Gene Of Pharbitis Nil, Priti Krishna, Roderick F. Felsheim, John C. Larkin, Anath Das Jan 1992

Structure And Light-Induced Expression Of A Small Heat-Shock Protein Gene Of Pharbitis Nil, Priti Krishna, Roderick F. Felsheim, John C. Larkin, Anath Das

Faculty Publications

To isolate genes that are regulated by a photoperiod that promotes flowering in Pharbitis nil, a cDNA library representing mRNA of induced cotyledons was screened by differential hybridization. The DNA sequence of one cDNA clone isolated by this approach, clone 12L, showed homology to plant small heat-shock protein (hsp) genes. P. nil genomic clones hybridizing to clone 12L were isolated, and the DNA sequences of two P. nil small hsp (shsp) genes, shsp-1 and shsp-2, were determined. The derived amino acid sequences of shsp-1 and shsp-2 showed maximum homology to the 17.9-kD soybean hsp, a member of the class II …

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Lsu General Catalog 1992-1993, Louisiana State University And Agricultural And Mechanical College Jan 1992

Lsu General Catalog 1992-1993, Louisiana State University And Agricultural And Mechanical College

LSU General Catalog

The LSU General Catalog describes all undergraduate and graduate departments and programs with degree requirements and courses offered for each one. The General Catalog includes information on registration and financial aid as well as academic services offered to all students.

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The Purification Of Mcrb And Mcrc Proteins In Mcrbc Restriction System Of Escherichia Coli K12 And Dna Sequencing Of The Region Downstream Of Mcrc., Ling Zheng Jan 1992

The Purification Of Mcrb And Mcrc Proteins In Mcrbc Restriction System Of Escherichia Coli K12 And Dna Sequencing Of The Region Downstream Of Mcrc., Ling Zheng

LSU Historical Dissertations and Theses

The McrBC restriction system of Escherichia coli K12 degrades methylcytosine-containing foreign DNA. Two genes mcrB and mcrC had been shown to be required for the McrBC restriction (Ross, et al., J. Bacteriol., 1989b). To explore the involvement of additional gene(s), a 1.7 kb fragment downstream of the mcrC was cloned and sequenced. Also mutants containing deletion in mcrBC or the downstream region were isolated by transposon excision. Genetic complementation studies confirmed that only DNA containing mcrB and mcrC gene on a high copy plasmid were needed to fully restored McrBC restriction. Deletion of the 1.7 kb fragment from or addition …

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The Epidemiology Of The Soybean/Diaporthe Phaseolorum Var. Caulivora Pathosystem In Louisiana., Guy Boyd Padgett Jan 1992

The Epidemiology Of The Soybean/Diaporthe Phaseolorum Var. Caulivora Pathosystem In Louisiana., Guy Boyd Padgett

LSU Historical Dissertations and Theses

Field and greenhouse experiments were conducted during 1988-1991 to investigate the epidemiology of the soybean/Diaporthe phaseolorum var. caulivora (Dpc) pathosystem. The following points were addressed: (i) the effect of inoculation timing on soybean yield and disease severity, (ii) the efficacy of Dpc inoculum during the growing season, (iii) the possibility of alternative hosts for Dpc, and (iv) the relationship between threecornered alfalfa hopper injury and stem canker severity. Inoculation timing had a significant effect on the yield of Dpc susceptible or moderately susceptible soybean cultivars. Soybean yield was reduced most (83 to 93%) and disease severity was greatest (84 to …

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Precision Cultural Practices For Commercial Vegetable Production, Richard L. Parish Jan 1992

Precision Cultural Practices For Commercial Vegetable Production, Richard L. Parish

LSU Agricultural Experiment Station Reports

No abstract provided.

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Gumbo Yearbook, Class Of 1992, Louisiana State University And Agricultural And Mechanical College Jan 1992

Gumbo Yearbook, Class Of 1992, Louisiana State University And Agricultural And Mechanical College

Gumbo Yearbook

The Gumbo yearbook chronicles the entire academic year at LSU. In words and especially photos, the Gumbo shows the people, places, and events that make each year unique. In addition to formal portraits of schools and departments, the book contains hundreds of snapshots of students with their friends and dozens of pages showcasing organizations.

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The Relation Between Stress And Insulin-Dependent Diabetes Mellitus: Physiologic Arousal Or Disruption Of Compliance?, Virginia Diane Garrett Jan 1992

The Relation Between Stress And Insulin-Dependent Diabetes Mellitus: Physiologic Arousal Or Disruption Of Compliance?, Virginia Diane Garrett

LSU Historical Dissertations and Theses

The relations between minor life events, compliance, urinary free cortisol, and blood glucose in 40 adults with insulin-dependent diabetes mellitus was examined. Specifically, this study explored whether naturally-occurring minor stressful events had disruptive effects on metabolic control through: (a) an arousal mechanism mediated by cortisol, (b) disruption of the individual's adherence to prescribed treatment, (c) a combination of arousal and disruption of compliance, or (d) a third, unspecified mechanism. Stress did not influence metabolic control, either independently or via a stress-compliance or stress-arousal mechanism although stress was related to cortisol activity. Neither the direct effects of cortisol nor a cortisol …

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The Effects Of Organoclay Adsorption On The Solidification Of Organic Wastes., Adam Faschan Jan 1992

The Effects Of Organoclay Adsorption On The Solidification Of Organic Wastes., Adam Faschan

LSU Historical Dissertations and Theses

The effects of organoclay adsorption on the leaching performance of solidified organic wastes was researched. Adsorption isotherms were developed for the adsorption of 1,2-dichlorobenzene (DCB), nitrobenzene (NB), and phenol by five different organoclays. Simulated liquid wastes containing DCB, NB, and phenol were solidified utilizing various combinations of Type I Portland cement and the five organoclays. The ratio of cement/clay utilized in each solidification matrix varied from 3/2 to 13/2. Linear and Langmuir adsorption isotherm models were utilized to predict the leaching performance of samples cured for 7, 28, and 90 days. The ratio of the actual leachate concentrations compared to …

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Dietary Restraint, Disinhibition Of Eating, And Resting Metabolic Rate In Women., Olga J. Lawson Jan 1992

Dietary Restraint, Disinhibition Of Eating, And Resting Metabolic Rate In Women., Olga J. Lawson

LSU Historical Dissertations and Theses

The effects of control (dieting) and loss of control over eating (overeating) on resting metabolic rate (RMR) were examined in a sample of 44 normal premenopausal women. A 2 (Restraint: High and Low) x 2 (Disinhibition: High and Low) design was utilized. Subjects were selected by their scores on the restraint and disinhibition scales of Three Factor Eating Questionnaire (Stunkard & Messick, 1985). The four groups were: women who alternated between dieting and overeating (HR/HD); women who dieted without overeating (HR/LD); women who did not diet or overeat (LR/LD); and women who did not diet and repeatedly overate (LR/HD). Body …

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Transgenic Rice Plants Containing A Chlorsulfuron Resistance Gene, A Hygromycin Resistance Gene And The Maizeactivator Transposable Element., Zhijian Li Jan 1992

Transgenic Rice Plants Containing A Chlorsulfuron Resistance Gene, A Hygromycin Resistance Gene And The Maizeactivator Transposable Element., Zhijian Li

LSU Historical Dissertations and Theses

A mutant Arabidopsis acetolactate synthase (ALS) gene csr-1-1, conferring chlorsulfuron resistance, was tested in transgenic rice to develop an alternative selectable marker for rice transformation. Up to a 200-fold increase in chlorsulfuron resistance was detected in transgenic rice calli expressing the mutant ALS gene under control of the CaMV 35S promoter. Efficient selection of resistant protoplast colonies was achieved by using 10 to 50 nM of chlorsulfuron after transformation with the 35S/ALS gene. Fertile transgenic rice plants were successfully recovered from 35S/ALS-containing transformants. These results demonstrated that the 35S/ALS gene could be used as a selectable marker gene in rice …

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The Black And White Differences In First Marriage Propensity: Individual And Contextual Influences., Jiang Hong Li Jan 1992

The Black And White Differences In First Marriage Propensity: Individual And Contextual Influences., Jiang Hong Li

LSU Historical Dissertations and Theses

In the context of demographic, economic, and cultural perspectives of marriage, this dissertation attempts to identify causes of the black and white divergence in marriage propensity. The findings show a strong linkage between the social context and the marriage behavior of that person. This linkage provides a new angle from which the racial differences in marriage behavior are better understood. For females, the lower rate of marrying among black females, compared to white females, is due to poor marriage markets that black females are facing. The centrality of marriage in a social context, indicated by marriage rates and average age …

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Assessment Of Depression In Adolescents: Relationship Between Iq, Depression, And Adaptive Behavior., Ramasamy Manikam Jan 1992

Assessment Of Depression In Adolescents: Relationship Between Iq, Depression, And Adaptive Behavior., Ramasamy Manikam

LSU Historical Dissertations and Theses

The primary focus of this investigation was to examine differences in depression, general psychopathology, and social skills among adolescents, and to identify the role of adaptive behavior between intelligence (I.Q.) and depression. One hundred adolescents, 13 through 17 years of age participated in this study. I.Q.s ranged between 40 to 130. Five levels of I.Q.s were studied (Above normal, Average, Borderline, Mild, Moderate). Three depression measures, the Child Depression Inventory (CDI), Reynolds Adolescent Depression Scale (RADS), Bellevue Index of Depression (BID), one social skills measure Matson Evaluation of Social Skills with Youngsters (MESSY), and one general psychopathology measure Psychopathology Instrument …

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Bifad Title Xii Coordinators' Perceptions Regarding Sustainable Agriculture., Lydia Vidjiawatie Ori Jan 1992

Bifad Title Xii Coordinators' Perceptions Regarding Sustainable Agriculture., Lydia Vidjiawatie Ori

LSU Historical Dissertations and Theses

The purpose of this study was to determine perceptions of coordinators with the Board of International Food and Agricultural Development (BIFAD) of sustainable agriculture, and practices and the ideas needed to promote it. The study also sought to verify Crosson's model of agricultural productivity and land potential. A three-part, field tested questionnaire was mailed to all 157 Title XII coordinators at Land Grant Universities throughout the United States. Of the 103 returned questionnaires a 58.6% usable response rate was obtained. An additional 21 responses obtained from nonrespondents reached by phone showed no significant differences from mail respondents. Descriptive statistics, Cramer's …

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Physiology And Biochemistry Of A Lignin-Degrading Bacterium Erwinia Sp. Cu 3614., Janardhanan S. Rajan Jan 1992

Physiology And Biochemistry Of A Lignin-Degrading Bacterium Erwinia Sp. Cu 3614., Janardhanan S. Rajan

LSU Historical Dissertations and Theses

Previous researchers have reported the isolation of a diphenylether cleaving organism, Erwinia sp., using an enrichment medium containing lignin. A copper and dinitrophenol resistant mutant of this organism, Erwinia sp. Cu3614, has also been reported. To assess the effect of copper on the growth and biochemistry of this organism, continuous cultivation was used employing an apparently optimized medium containing ethanol as carbon source. Upon increasing the concentration of copper sulfate in the medium from 5 $\mu$g/ml to 10 $\mu$g/ml increases in maximum specific growth rate and growth yield were seen. Also decrease in the values for doubling time and the …

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Shoot Growth And Form Of Senna Obtusifolia In Response To Soybean And Intraspecific Competition., James Edward Smith Jan 1992

Shoot Growth And Form Of Senna Obtusifolia In Response To Soybean And Intraspecific Competition., James Edward Smith

LSU Historical Dissertations and Theses

Effects of competition on growth and formation of shoot structure in sicklepod (Senna obtusifolia) were examined, with particular emphasis on the effect of nearest neighbors on branching and canopy formation. Sicklepod was established as (1) stands of 26 plants m$\sp{-2}$ added to soybean, (2) individuals widely enough spaced to produce only interspecific competition when added to soybean, or (3) regularly spaced monoculture stands with 15, 25, 35, and 50 cm interplant distances. Repeated surveys of individual shoots characterized sicklepod growth and shoot structure in terms of position of and growth at each node. Sicklepod leaf area, internode elongation, node production, …

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Attention Deficit-Hyperactivity Disorder Among Mentally Retarded Children., Virginia Elaine Fee Jan 1992

Attention Deficit-Hyperactivity Disorder Among Mentally Retarded Children., Virginia Elaine Fee

LSU Historical Dissertations and Theses

Teachers completed the CTRS-39 on 100 boys assigned to one of four groups based on IQ and scores on a DSM-III-R checklist of the symptoms for Attention Deficit-Hyperactivity Disorder (AD-HD). The groups included a normal control group, children with AD-HD, mentally retarded children, and mentally retarded children with AD-HD. There were no significant differences between the AD-HD group and the mentally retarded AD-HD group on all but one of the Conners' Factors and no significant differences on the IOWA Conners' Scales that were extracted from the CTRS-39. Mentally retarded children in general were found to be more anxious than their …

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Selection And Characterization Of Populations Of Rapid-Cycling Brassica Rapa L. Differing In Their Response To Rootzone Hypoxia., Christine Jo Daugherty Jan 1992

Selection And Characterization Of Populations Of Rapid-Cycling Brassica Rapa L. Differing In Their Response To Rootzone Hypoxia., Christine Jo Daugherty

LSU Historical Dissertations and Theses

Challenging a heterogenous population of plants (rapid-cycling Brassica rapa L.) with waterlogging, we selected plants which differed in their response to rootzone hypoxia. Based on visual criteria, individuals from the waterlogged wild-type population were separated into "tolerant" and "sensitive" groups and mass pollinated to produce the next generation. This selection protocol was continued for seven generations. Under waterlogged conditions, chlorophyll concentrations in the tolerant population were significantly greater than in the sensitive population. After eight days of waterlogging, tolerant plants had significantly greater dry root and shoot weights than the sensitive plants. However, when tolerant and sensitive populations were grown …

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Investigations Into The Pathogenesis Of Acute Equine Laminitis., Linda Elizabeth Cummings Jan 1992

Investigations Into The Pathogenesis Of Acute Equine Laminitis., Linda Elizabeth Cummings

LSU Historical Dissertations and Theses

A profound decrease in perfusion of the laminar capillaries has been documented during acute equine laminitis, resulting in ischemia of the laminar tissue. Oxygen radicals are believed to mediate ischemia/reperfusion injury. The effects of (1) three hours of surgical ligation of the major blood supply of the equine digit followed by ligature release, (2) resection of the medial and lateral palmar digital arteries, and (3) digital intraarterial infusions of an oxygen radical generating system, were investigated. Laminitis was not induced by any of these manipulations. Clinical signs and alterations in hemograms observed following these procedures are reported. Preliminary identification of …

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Further Psychometric Properties Of The Mother's Activity Checklist., Linda Merideth Little Jan 1992

Further Psychometric Properties Of The Mother's Activity Checklist., Linda Merideth Little

LSU Historical Dissertations and Theses

The present study attempted to extend the results obtained by Kelley and Carper (1988) regarding the psychometric properties of the Mother's Activity Checklist utilizing a larger, more heterogeneous sample of mothers. The MAC is a 100-item checklist of pleasant and unpleasant setting events which mothers frequently experience. A revised version of the MAC consisting of 45 items was developed utilizing factor analysis procedures. The revised version consists of four factors: Pleasant Events, Unpleasant Events, Aversive Child Behavior, and Aversive Marital Events. Utilizing a sample of eight hundred and thirty-three mothers with children between the ages of 2 and 12, both …

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Predicting Success Of Minority Nursing Students On The "New" Nclex-Rn., Janet Simmons Rami Jan 1992

Predicting Success Of Minority Nursing Students On The "New" Nclex-Rn., Janet Simmons Rami

LSU Historical Dissertations and Theses

The purpose of this study was to identify academic variables that could be used to forecast success for minority, baccalaureate (BSN) students enrolled in higher education in the south. A second purpose was to develop a methodological framework for predicting success on the post-1988 versions of the National Council Licensure Examination for Registered Nurses (NCLEX-RN), that enhanced external validity, and generalizability. The best predictors of success for minority BSN nursing students were the Mosby assesstest, school comprehensive exit exams, GPA microbiology, the college cumulative GPA, nursing course cumulative GPA, and ACT composite. The sample included 216 Black graduates of three …

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The Effect Of Instructional Videos And Simulation-Gaming Activities In The Environmental Science Curriculum On Knowledge And Attitudes., Lyle Mark Soniat Jan 1992

The Effect Of Instructional Videos And Simulation-Gaming Activities In The Environmental Science Curriculum On Knowledge And Attitudes., Lyle Mark Soniat

LSU Historical Dissertations and Theses

As a result of science reform efforts in the United States numerous shortcomings of the predominant curricula have been identified. The following study evaluates a modular, environmental science curriculum entitled Wild Louisiana, which attempts to address these shortcomings. Wild Louisiana is Science-Technology-Society (STS) oriented and infuses regionally based instructional videos and simulation-gaming activities into the secondary science curriculum. The videos and activities depict the confluence of regional biological, technical, and social phenomena to illustrate universal environmental concepts. The multimedia, modular approach is intended to address the varied learning styles of different students. Following random selection, teachers were randomly assigned to …

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Effects Of Stress, Dietary Restraint, And Disinhibition Upon Eating Habits And Nutrition., Barbara Ann Cubic Jan 1992

Effects Of Stress, Dietary Restraint, And Disinhibition Upon Eating Habits And Nutrition., Barbara Ann Cubic

LSU Historical Dissertations and Theses

Restraint theory states that for some individuals physiological factors which normally result in eating compete with cognitive efforts to resist eating (i.e. dietary restraint). This disparity has been hypothesized to result in a chronic state of stress which leads to reduced behavioral control and increased negative affect. It has been presumed that dietary restraint is a precondition for overeating. Despite the legitimacy of proposing a link between stress, dietary restraint and overeating this interaction has not received intensive study. Furthermore, studies which have attempted to assess this relationship have not investigated the possible independent and interactive influences each of these …

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The Effects Of Exercise Stress On Equine Immune Function., Tammie Lee Keadle Jan 1992

The Effects Of Exercise Stress On Equine Immune Function., Tammie Lee Keadle

LSU Historical Dissertations and Theses

The physiologic demands of exercise constitute a form of stress which is accompanied by modulation of immune responses. However, numerous studies in many different model systems have failed to clearly define the effects of exercise on immunity. Furthermore, the role of the neuroendocrine system in exercise-induced immunomodulation has been largely unexplored. To address these issues, we evaluated the effect of acute exercise stress on 3 indices of immune function in horses, before and after completion of a 12 week treadmill-based physical conditioning program. In addition, we determined the effects of corticosteroids, catecholamines, beta endorphin, and adrenocorticotropic hormone on these same …

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Physiological Studies On Postharvest Leaf Blackening In Cut Flower Protea Species., Margaret Robyn Mcconchie Jan 1992

Physiological Studies On Postharvest Leaf Blackening In Cut Flower Protea Species., Margaret Robyn Mcconchie

LSU Historical Dissertations and Theses

To develop an understanding of the physiology which results in postharvest leaf blackening, cut flower Protea species were studied in relation to changes in leaf carbohydrate metabolism, membrane deterioration, and oxidative enzyme activity. Rapid development of leaf blackening in the dark was correlated with low starch and sucrose concentrations. Postharvest decline in leaf carbohydrate status appears to be associated with inflorescence sink demand. Leaf blackening was reduced in the light and carbohydrate pools were maintained due to photosynthesis. In floral stems of P. neriifolia, P. Susannae x compacta and P. eximia (which have differing susceptibilities to leaf blackening), leaf blackening …

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Attitudes Toward International Harmonization Efforts: A Cross-Cultural Study., M. Aileen Smith Jan 1992

Attitudes Toward International Harmonization Efforts: A Cross-Cultural Study., M. Aileen Smith

LSU Historical Dissertations and Theses

The last two decades have seen a significant increase in the number and size of multinational corporations and a growing global investment environment. Linked to that growth has been a call for standards that produce accounting information that is capable of crossing national boundaries. One of the groups of professional elites that have addressed the call for harmonized international accounting standards is the International Accounting Standards Committee (IASC). The IASC objective (IASC 1988, 1) states that it will "work generally for the improvement and harmonization of regulations, accounting standards and procedures ... " To address such a goal, the IASC …

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The Molecular Systematics Of Unitunicate, Perithecial Ascomycetes., Joseph William Spatafora Jan 1992

The Molecular Systematics Of Unitunicate, Perithecial Ascomycetes., Joseph William Spatafora

LSU Historical Dissertations and Theses

Maximum parsimony analysis of partial sequences from the small subunit ribosomal DNA (ssrDNA) rejects the monophyly of unitunicate, perithecial ascomycetes (pyrenomycetes). The genera Kathistes, Pyxidiophora and Subbaromyces are separated from a large clade of relatively derived pyrenomycetes. This derived pyrenomycete clade is supported by a bootstrap confidence level of 100% and a decay index of $>$10 steps, and contains two subclades, A and B. Subclade A comprises the orders Clavicipitales, Hypocreales, Microascales and the genus Ceratocystis; subclade B consists of the Diaporthales, Sordariales, Xylariales and the genus Ophiostoma. The Clavicipitales is a sister taxon to the Hypocreales, which consists …

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A Study On The Aquic Conditions Of Two Natraqualfs In The Coastal Plain Of Louisiana., Ariel Alejandro Szogi Jan 1992

A Study On The Aquic Conditions Of Two Natraqualfs In The Coastal Plain Of Louisiana., Ariel Alejandro Szogi

LSU Historical Dissertations and Theses

This study had the purposes of investigating the aquic conditions of two selected Natraqualfs to define the relationship between wetness and morphological properties and prediction of major soil processes. The proposed criteria for aquic conditions as defined by the International Committee on Aquic Conditions (ICOMAQ) were identified by: (i) presence of redoximorphic features, and (ii) measurement of saturation and reduction. They were used to locally verify morphological inferences used to predict the aquic conditions. Morphological properties and laboratory analysis were used to predict the periodicity and duration of saturation and reduction. Soil and ground water analyses were used to understand …

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Studies On Escherichia Coli Cell Division: Overexpression, Purification, And Quantitative Determination Offtsa Protein., Haichao Wang Jan 1992

Studies On Escherichia Coli Cell Division: Overexpression, Purification, And Quantitative Determination Offtsa Protein., Haichao Wang

LSU Historical Dissertations and Theses

FtsA is an essential cell division protein which is synthesized in minute amounts in Escherichia coli. To study the effects of overexpressing ftsA on the phenotype of E. coli cells, DNA fragments encoding the ftsA gene were subcloned downstream of a lac or a tac promoter in two plasmids. High-level expression of the ftsA gene from these promoters inhibited normal cell septation and caused the cells to become long, nonseptate filaments. Continued overexpression of ftsA resulted in the filaments developing spherical bulges up to 4 um in diameter. It is suggested that these bulges may emanate from septation sites because …

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The Effects Of Dietary Sodium Zeolite A On Growth And Mineral Utilization Of Chickens., Kevin Lee Watkins Jan 1992

The Effects Of Dietary Sodium Zeolite A On Growth And Mineral Utilization Of Chickens., Kevin Lee Watkins

LSU Historical Dissertations and Theses

Four experiments were conducted to investigate the effects of sodium zeolite A (SZA) on calcium (Ca), phosphorus (P), and zinc (Zn) utilization in broiler chickens from 5 to 14 or 15 days of age. In Experiment 1, two levels each of SZA (0 and.75%) and (or) Ca (1.0 and 1.5%) were fed to both uninfected and Eimeria acervulina-infected chicks. Excess dietary Ca reduced (P $$.10) in infected chicks (Ca x coccidiosis, P $<$.05). Addition of SZA to diets with excess Ca further decreased (P $<$.05) gain and tibia ash. These results suggest that SZA may exacerbate the adverse effects of excess dietary Ca. In Experiment 2, four levels of dietary Ca (.6,.8, 1.0, and 1.2%) and (or) two levels of SZA (0 and.75%) were fed. Sodium zeolite A decreased (P $<$.05) plasma P and tibia magnesium (Mg) but increased (P $<$.05) tibia Ca, Zn, aluminum (Al), and manganese (Mn). Tibia ash and shearing force were increased in chicks fed SZA and inadequate dietary Ca, but were decreased in chicks fed SZA and 1.2% Ca (Ca x SZA, P $<$.05). Dietary SZA enhanced tibia ash, density, and shearing force when dietary Ca was low; however, SZA reduced many bone mineralization indices in chicks fed excess Ca. In Experiment 3, various levels of dietary P (.41,.55, and.69%), Ca (.6 and 1%), and (or) SZA (0 and.75%) were fed. The addition of Ca, SZA, or both exacerbated the adverse effects of feeding low-P diets, yet alleviated the adverse effects of feeding low-Ca, high-P diets. Dietary SZA reduced (P $<$.01) plasma P and increased (P $<$.02) tibia Mn, Zn, copper (Cu), and Al. The SZA-induced increase in tibia Al was most evident in chicks fed low levels of P (SZA x P, P $<$.02). These data demonstrate that the effects of SZA are influenced by dietary concentrations of Ca and P, and that the addition of SZA to diets low in P results in bone Al accumulation. In Experiment 4, the effects of SZA on chicks fed inadequate (35 ppm), marginal (40 ppm), adequate (85 ppm), and excess (4,000 ppm) levels of Zn were assessed. Sodium zeolite A increased (P $<$.05) tibia and pancreas Zn regardless of dietary Zn concentration. Dietary SZA tended to alleviate the adverse effects of feeding inadequate Zn and exacerbate the adverse effects of feeding excess Zn.

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