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Investigations Of Ultrafast Dynamics Of Photoexcited Hemeproteins And Iodomethane In Condensed Phase Using Transient Raman And Absorption Spectroscopies., Huiping Zhu Jan 1993

Investigations Of Ultrafast Dynamics Of Photoexcited Hemeproteins And Iodomethane In Condensed Phase Using Transient Raman And Absorption Spectroscopies., Huiping Zhu

LSU Historical Dissertations and Theses

This dissertation describes the development and application of transient Raman and absorption spectroscopies using 8 ps laser pulses for the study of photoexcitation dynamics of hemeproteins and CH$\sb3$I in the condensed phase. Transient Raman spectroscopy is a powerful ultrafast technique. Hemeproteins have been studied using this technique. The dynamics of vibrational cooling, geminate recombination, and structural change upon the photoexcitation of hemeproteins have been unambiguously separated. The vibrationally hot deoxyhemoglobin, oxyhemoglobin and photoproduct deoxy-liked hemoglobin have been directly detected. The deconvolved time constant of vibrational cooling for the species is about 2-5 ps. Direct evidence for the lack of geminate …

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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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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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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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Demonstration Of A Control Strategy For Sustained Algal Growth At A Full-Scale Level Under Computer-Automated, Continuous Culture Conditions., Kelly Ann Rusch Jan 1992

Demonstration Of A Control Strategy For Sustained Algal Growth At A Full-Scale Level Under Computer-Automated, Continuous Culture Conditions., Kelly Ann Rusch

LSU Historical Dissertations and Theses

A computerized algal turbidostat was designed and constructed for use in aquaculture facilities requiring a continuous feed source. Continuous cultures, maintained in the exponential growth phase by the continual introduction of fresh media, exhibit a steadystate nature easily adaptable to computer automation and optimization processes. These characteristics, in contrast to batch culture methods, result in both reduced land and labor requirements; an important consideration for commercial applications wherein algal production occupies as much as 40 percent of a facility in both space and cost. The turbidostat system consisted of two 0.6 m$\sp3$ growth chambers supported by a central monitoring block …

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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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Seasonal Response Of Slash Pine (Pinus Elliottii Var. Elliottii Engelm.) Photosynthesis To Long‐Term Exposure To Ozone And Acidic Precipitation, David P. Byres, Jon D. Johnson, Thomas J. Dean Jan 1992

Seasonal Response Of Slash Pine (Pinus Elliottii Var. Elliottii Engelm.) Photosynthesis To Long‐Term Exposure To Ozone And Acidic Precipitation, David P. Byres, Jon D. Johnson, Thomas J. Dean

Faculty Publications

Four half‐sib families of slash pine (Pinus elliottii var. elliottii) were planted in open‐top chambers and exposed to ozone and simulated acidic precipitation (3: 7 molar ratio of nitric and sulphuric acids). The 4 ozone treatments were (1) charcoal‐filtered air, (2) unfiltered ambient air, (3) twice ambient and (4) three times ambient ozone, with treatments applied 12 h per day, 11 months per year for 28 months. Seedlings were irrigated weekly with one of three rain acidities: pH 33, 4.3 or 5.3 at a total rainfall equivalent of 133 cm per year. Photosynthetic rates were measured approximately every 10 weeks, …

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Long‐Term Effects Of Ozone And Simulated Acid Rain On The Foliage Dynamics Of Slash Pine (Pinus Elliottii Var. Elliottii Engelm.), David P. Byres, Thomas J. Dean, Jon D. Johnson Jan 1992

Long‐Term Effects Of Ozone And Simulated Acid Rain On The Foliage Dynamics Of Slash Pine (Pinus Elliottii Var. Elliottii Engelm.), David P. Byres, Thomas J. Dean, Jon D. Johnson

Faculty Publications

Seedlings from four half‐sib families of Pinus elliottii var. elliottii Engelm. were planted in open‐top chambers, and exposed to ozone and simulated acidic precipitation. Treatments were applied for 11 months per year for 28 months. The ozone concentrations were: charcoal filtered air (CF), nonfiltered ambient air (1×), twice the nonfiltered level (2 ×) and three times the nonfiltered level (3 ×). Ozone exposures were computer controlled to follow natural diurnal fluctuations in ambient ozone concentrations. Simulated acid rain at pH 3.3, 4.3 or 5.3 was delivered weekly at the same volume as average weekly rainfall to all chambers. Leaf area, …

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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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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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Effects Of Heat And Iron Fractions On Lipid Oxidation In Meat., Dongmei Han Jan 1992

Effects Of Heat And Iron Fractions On Lipid Oxidation In Meat., Dongmei Han

LSU Historical Dissertations and Theses

Size exclusion (SE) and hydrophobic interaction (HIC) high performance liquid chromatography (HPLC) methods were developed for determining hemoglobin, myoglobin, and total pigments in beef and chicken. Hemoglobin and myoglobin in beef, but not in chicken, were separated by HIC with minimum detectable levels of 0.187 and 0.085 $\mu$g/$\mu$l, respectively. Determination of total pigment by SE-HPLC (minimum detection of 0.001 $\mu$g/$\mu$l) was more sensitive than with spectrophotometric assay. The effects of heat at 55$\sp\circ$C, 70$\sp\circ$C, 85$\sp\circ$C, and 100$\sp\circ$C on the distribution of iron in six fractions (water-soluble, water-insoluble, diffusate, hematin, total heme, and ferritin) in beef and chicken muscles were determined. …

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Host Quality Of Baldcypress And Its Influence On Fruittree Leafroller, Archips Argyrospila (Walker) (Lepidoptera: Tortricidae), Performance In Forested Wetlands Of Louisiana., James R. Meeker Jan 1992

Host Quality Of Baldcypress And Its Influence On Fruittree Leafroller, Archips Argyrospila (Walker) (Lepidoptera: Tortricidae), Performance In Forested Wetlands Of Louisiana., James R. Meeker

LSU Historical Dissertations and Theses

Ecological relationships between the fruittree leafroller (FTLR), (Archips argyrospila (Walker)) and a new host, baldcypress (Taxodium distichum (L.)), were investigated in southern Louisiana where persistent annual defoliation over increasingly larger areas has occurred since 1983. Defoliation was observed to correspond with common types of baldcypress foliage morphology; designated as open and appressed. Pondcypress, Shumard oak and citrus foliage also were examined. The objectives were to: (1) determine the relative suitability/susceptibility of foliage types, and (2) quantify parameters of foliage quality possibly influencing FTLR performance. Levels of defoliation, egg mass counts, and laboratory bioassays of: initial survival, host preference, growth, feeding, …

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Applicability Of Bioluminescence Assay And Aerobic Bacterial Counts For The Evaluation Of Raw Milk Quality., Abdul Ghafoor Mian Jan 1992

Applicability Of Bioluminescence Assay And Aerobic Bacterial Counts For The Evaluation Of Raw Milk Quality., Abdul Ghafoor Mian

LSU Historical Dissertations and Theses

Raw milk samples were analyzed to determine the bacteriological quality by the standard plate count (SPC), adenosine-5$\sp\prime$-triphosphate (ATP) assay, preliminary incubation counts, and the psychrotrophic bacteria count (PBC). In a comparison of SPC and ATP content, an overall correlation coefficient of 0.97 was found between the two methods. The correlations between ATP content and SPC of fresh raw milk samples at zero hour and after preliminary incubating these samples at 12.8 and 15.6$\sp\circ$C for 18 hours were.96,.97, and.97, respectively. The regression coefficients for all types of milk samples were highly significant ($P <$.01). High correlation coefficients demonstrated that the ATP measurement in combination with preliminary incubation practices could be a rapid technique for the determination of bacteriological quality of milk at receiving stations and milk processing plants. Median SPC for 175 fresh raw milk samples was 36,000/ml. The bioluminescence technique is reported previously to have a good correlation with SPC in the range of 1.0 $\times$ 10$\sp5$ to 1.0 $\times$ 10$\sp{10}$ bacteria/ml. The commingled milk coming at the receiving stations sometimes have a bacterial count that is less than 1.0 $\times$ 10$\sp{5}$ bacteria/ml. A correlation coefficient of.87 was calculated between the SPC and ATP values for the overall data while lowering the SPC range from 1.0 $\times$ 10$\sp5$ to 1.0 $\times$ 10$\sp4$ bacteria/ml. This range is more practical as a quick screening of raw milk at dairy processing facilities since 81 percent of all raw milk samples fell in this range. An equation (SPC = $-$1642213 + 6751(ATP)) was developed from the combined experimental data which could estimate the SPC of raw milk samples using their ATP content. Another phase of the experiment was to ascertain if the Petrifilm$\sp{\rm TM}$ technique could be effectively used in place of agar method to estimate PBC. The correlation coefficient between the Petrifilm$\sp{\rm TM}$ and the agar plate method for both the fresh and preliminary incubated raw milk samples was.99. A high linearity of relationship shows that one method can be substituted with the other. However, the Petrifilm$\sp{\rm TM}$ technique took longer than the usual time of 25 h to develop red colonies at 21$\sp\circ$C because of the slow reduction of the dye reagent triphenyl tetrazolium chloride (TTC) at this temperature.

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Developing A Research Agenda For The Louisiana Cooperative Extension Service., Fred S. Sanders Jr Jan 1992

Developing A Research Agenda For The Louisiana Cooperative Extension Service., Fred S. Sanders Jr

LSU Historical Dissertations and Theses

The primary purpose of this study was to determine potential future research priorities for the Louisiana Cooperative Extension Service. The Delphi method of forecasting was determined to be the most appropriate for use in this study. Having a knowledge of, and a current relationship with, the Louisiana Cooperative Extension Service (LCES) was the initial criteria for selecting panelists for this study. The final panel consisted of forty LCES personnel. Three rounds of questionnaires were used in this study. The Round 0 questionnaire was open-ended and was used to generate a list of perceived research items most in need of research …

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Influences On The Instream Distribution Of Astyanax Fasciatus In A Small River In Costa Rica., Cecil Kelly Swing Jan 1992

Influences On The Instream Distribution Of Astyanax Fasciatus In A Small River In Costa Rica., Cecil Kelly Swing

LSU Historical Dissertations and Theses

The instream distribution of the tetra, Astyanax fasciatus, was investigated through approximately 700 hours of field observations in a small Costa Rican stream on the southwestern Pacific coast near Golfito. Individuals tended to remain in particular pools where they subsisted primarily on a diet of terrestrial insects. These fish were able to migrate, and only as many individuals stayed in any pool as could be sustained there by available food resources. Because the water intercepted insects fairly uniformly over its surface, the biomass of fish occupying any particular pool was proportional to its surface area (r$\sp2$ = 0.652). The amount …

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A Novel Process For The Production Of Clinical Dextran., Doman Kim Jan 1992

A Novel Process For The Production Of Clinical Dextran., Doman Kim

LSU Historical Dissertations and Theses

A new process for the production of clinical (or controlled size) dextran was developed. This process is simpler, cheaper and more economical than traditional methods. It involves the use of a mixed culture fermentation with a dextranase producing strain (Lipomyces starkeyi ATCC 74054) and a dextransucrase producing strain (Leuconostoc mesenteroides ATCC 10830). The new process produced 84% (w/w) of theoretical yield clinical dextran with an average polydispersity between 1.2 and 1.5. The mechanism of clinical dextran formation is the competitive production of acceptors from newly formed dextran molecules by dextranase. The acceptors compete for the existing glucosyl portion of sucrose, …

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Effect Of Soil Redox Potential Andph On Nutrient Uptake By Rice With Special Reference To Arsenic Forms And Uptake., Alfredo Ruben Marin Jan 1992

Effect Of Soil Redox Potential Andph On Nutrient Uptake By Rice With Special Reference To Arsenic Forms And Uptake., Alfredo Ruben Marin

LSU Historical Dissertations and Theses

Studies dealing with the availability and speciation of arsenic (As) as affected by soil redox potential and pH were initiated because of the lack of information on As chemistry in flooded soils. The chemistry of native and applied As was studied in a Crowley silt loam soil (Typic Albaqualf). Arsenic uptake and its toxic effect on two rice cultivars as affected by As chemical form and concentration were also studied. Soil redox potential and pH were shown to affect speciation and solubility of both native and applied As. Upon soil reduction, indigenous-As solubility increased, and arsenite (As(III)) comprised most of …

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Identification Of Plant Science Concepts Needed In Agriscience Programs Of The Future., Camile Patrick Gaspard Jan 1992

Identification Of Plant Science Concepts Needed In Agriscience Programs Of The Future., Camile Patrick Gaspard

LSU Historical Dissertations and Theses

The purpose of this study was to identify the plant science concepts which should be taught in secondary agriculture programs of the future as perceived by innovators in the field of plant science. The Delphi technique was used to gain the perceptions of a nation-wide panel of plant science professionals. The panel was comprised of three groups of plant scientists: secondary plant science teachers, university plant scientists, and plant scientists working in industry. The secondary plant science teachers were selected from the national and regional winners of the agriscience teacher award. The university plant scientists and plant scientists working in …

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Louisiana Agriculture Magazine, Fall 1991, Lsu Agricultural Experiment Station Oct 1991

Louisiana Agriculture Magazine, Fall 1991, Lsu Agricultural Experiment Station

Louisiana Agriculture

No abstract provided.

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Louisiana Agriculture Magazine, Summer 1991, Lsu Agricultural Experiment Station Jul 1991

Louisiana Agriculture Magazine, Summer 1991, Lsu Agricultural Experiment Station

Louisiana Agriculture

No abstract provided.

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Louisiana Agriculture Magazine, Spring 1991, Lsu Agricultural Experiment Station Apr 1991

Louisiana Agriculture Magazine, Spring 1991, Lsu Agricultural Experiment Station

Louisiana Agriculture

No abstract provided.

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Sensitivity Of Frost Resistance And Growth In Citrus And Avocado To Chronic Ozone Exposure, D. M. Eissenstat, J. P. Syvertsen, T. J. Dean, G. Yelenosky, J. D. Johnson Jan 1991

Sensitivity Of Frost Resistance And Growth In Citrus And Avocado To Chronic Ozone Exposure, D. M. Eissenstat, J. P. Syvertsen, T. J. Dean, G. Yelenosky, J. D. Johnson

Faculty Publications

The effects of elevated levels of ozone on growth and frost resistance were studied using broadleaf‐evergreen citrus and avocado trees. ‘Ruby Red’ grapefruit (Citrus parodist L.) trees on either Volkamer lemon (Citrus volkanieriana Ten. & Pasq.) or sour orange (Citrus aurantium L.) rootstocks and ‘Simmonds’ or ‘Pancho’ avocado trees (Persea americana Mill.) on the rootstock ‘Waldin’ were exposed to ozone in open‐top chambers for 4 months in 1988 and for 8 months in a second experiment in 1989. The ambient ozone concentration, averaged over a 12 h day, was 30‐1 nl 1−1 in 1988 and 39‐1 nl 1−1 in 1989 …

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Computer-Simulated Evaluation Of Possible Mechanisms For Quenching Heavy Metal Ion Activity In Plant Vacuoles: I. Cadmium, Jian Wang, Bill P. Evangelou, Mark T. Nielsen, George J. Wagner Jan 1991

Computer-Simulated Evaluation Of Possible Mechanisms For Quenching Heavy Metal Ion Activity In Plant Vacuoles: I. Cadmium, Jian Wang, Bill P. Evangelou, Mark T. Nielsen, George J. Wagner

Faculty Publications

Various mechanisms have been suggested for the quenching of Cd ion activity in plant vacuoles. These include solution complexation with organic acids and sulfhydryl-containing peptides and precipitation as sulfides. Because direct experimental support for these mechanisms is lacking and difficult to obtain, we have used a computer model to evaluate the quenching role of possible organic and inorganic ligands of tobacco cultured cells exposed to Cd. Results of this thermodynamic evaluation, which assumes that a chemical equilibrium state is met in the vacuole, support the conclusion that sulfhydryl-containing peptides and certain organic acids may form soluble Cd complexes. Although complexation …

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The Morphology, Development, And Function Of Experimentally Induced Macrophage Aggregates In Rivulus Marmoratus., Wolfgang Klaus Vogelbein Jan 1991

The Morphology, Development, And Function Of Experimentally Induced Macrophage Aggregates In Rivulus Marmoratus., Wolfgang Klaus Vogelbein

LSU Historical Dissertations and Theses

Calyptospora funduli is a pathogenic coccidium that infects the liver and pancreas of estuarine killifishes belonging to the genus Fundulus. Experimental infection of the atypical fish host Rivulus marmoratus with this intracellular protozoan parasite caused the development of hepatic macrophage aggregates (MA's) and granulomas. The Rivulus/Calyptospora host-parasite system thus represents a new laboratory model for investigations of MA biology. In the present study, this model was used to: (1) examine the morphology and sequential development of the parasite-elicited hepatic MA's in R. marmoratus, (2) define the role that these structures play in the pathogenesis of an infectious disease process, and …

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The Immunoepidemiology Of Lung Cancer And Smoking: Lymphocyte Subsets., Joan Peters Blackmon Jan 1991

The Immunoepidemiology Of Lung Cancer And Smoking: Lymphocyte Subsets., Joan Peters Blackmon

LSU Historical Dissertations and Theses

The relative proportions of lymphocyte subsets in the peripheral blood constitute a measure of immune status. Results of research to establish whether or not individuals with lung cancer differ in their lymphocyte composition have conflicted due to failure to control for factors other than cancer that affect lymphocyte balance. This study was designed to quantitatively estimate the effects of variables such as disease (lung cancer), smoking, age, circadian and circannual rhythms, and dietary factors on lymphocyte subsets. Questionnaires were given to 64 white males with primary lung cancer and 219 cancer-free white males and a blood sample was obtained. Lymphocytes …

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Genotype X Environment Interaction For Growth And Reproductive Traits In Beef Cattle., Louis Munyakazi Jan 1991

Genotype X Environment Interaction For Growth And Reproductive Traits In Beef Cattle., Louis Munyakazi

LSU Historical Dissertations and Theses

Data on eight different two breed combinations of calves produced in two locations (Louisiana and Nebraska) were analyzed to determine the magnitude of genotype x location interactions for gestation length (GESTLEN), birth weight (BWT), pre-weaning average daily gain (ADG) and weaning weight (WWT). Sire breed (SB), sire/SB and cow breed (CB) interactions with location (LOC) were the primary sources of variation of interest in the analysis of variance. The SB x LOC interaction was significant for all traits whereas the CB x LOC interaction was important only for ADG. The sire/SB x LOC interaction accounted for a significant amount of …

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In Vitro Culture Of Bovine Uterine And Oviduct Epithelial Cells., John Kevin Thibodeaux Jan 1991

In Vitro Culture Of Bovine Uterine And Oviduct Epithelial Cells., John Kevin Thibodeaux

LSU Historical Dissertations and Theses

A reliable procedure was developed to harvest purified populations of bovine uterine epithelial cells from the luminal endometrium that allowed cells to be maintained in vitro for multiple subpassages. This method allowed adequate numbers of cells for in vitro culture studies to evaluate uterine secretion rates, uterine-embryo interactions and a new embryo co-culture system. In a second study, cells were isolated from the uterus and oviducts collected from cattle on day of estrus, on d 4 to 6, d 8 to 10 and d 14 to 16 of the cycle to monitor growth and development following incubation in vitro. The …

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Response Of Determinate Soybean Cultivars To Low Ph Soils., J E. Board Jan 1991

Response Of Determinate Soybean Cultivars To Low Ph Soils., J E. Board

LSU Agricultural Experiment Station Reports

No abstract provided.

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