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1996

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The Relationship Of Hemolymph Sugar, Juvenile Hormone And Biogenic Amines To The Three Behavioral States Of Mature Honey Bees., Janko Bozic Jan 1996

The Relationship Of Hemolymph Sugar, Juvenile Hormone And Biogenic Amines To The Three Behavioral States Of Mature Honey Bees., Janko Bozic

LSU Historical Dissertations and Theses

Differences in sugar titers, JH synthesis rate and biogenic amine metabolism correlated with three distinct activity groups or mature bees: resting bees, followers and dancers. Dancers had lower trehalose titers than followers or resting bees. In absconding bees trehalose titers were even lower, due to greatly elevated locomotor activity. The collecting and transferring of food by dancers and followers resulted in a higher glucose titer than in resting bees. Followers had a higher-JH synthesis rate than dancers, suggesting that JH could be an internal motivational stimulus to recruit followers to forage. Dancers and followers collect and transfer food and therefore …

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Work Motivation And Perceived Organizational Effectiveness In Middle Schools., Cynthia Young Wren Jan 1996

Work Motivation And Perceived Organizational Effectiveness In Middle Schools., Cynthia Young Wren

LSU Historical Dissertations and Theses

The primary purpose of this study was to determine the linkage between work motivation derived from the expectancy theory and perceived organizational effectiveness derived from the Parsonian framework. School characteristics of community type, school size, and school socioeconomic status were used as predictor variables in the study. A secondary purpose was to examine these linkages in middle schools and to examine changes over time. Mixed methodologies, including quantitative and qualitative research techniques, were employed. The data were analyzed using the school and the individual teacher as units of analyses. To test the hypotheses, a multiple regression procedure was employed. The …

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Robust Sensor Fusion Algorithms: Calibration And Cost Minimization., Richard Ree Brooks Jan 1996

Robust Sensor Fusion Algorithms: Calibration And Cost Minimization., Richard Ree Brooks

LSU Historical Dissertations and Theses

A system reacting to its environment requires sensor input to model the environment. Unfortunately, sensors are electromechanical devices subject to physical limitations. It is challenging for a system to robustly evaluate sensor data which is of questionable accuracy and dependability. Sensor fusion addresses this problem by taking inputs from several sensors and merging the individual sensor readings into a single logical reading. The use of heterogeneous physical sensors allows a logical sensor to be less sensitive to the limitations of any single sensor technology, and the use of multiple identical sensors allows the system to tolerate failures of some of …

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An Attempt To Classify The Production And Regulation Of Cyclooxygenase-2 During Ovulation And Luteolysis., James Robert Broussard Jan 1996

An Attempt To Classify The Production And Regulation Of Cyclooxygenase-2 During Ovulation And Luteolysis., James Robert Broussard

LSU Historical Dissertations and Theses

A series of experiments were designed to determine the cyclooxygenase (COX) isoform responsible for prostaglandin release during ovulation and luteolysis. Initially, a reliable, serum-free culture system was developed to produce large numbers of bovine granulosa cells originally harvested from the small antral follicles of abattoir ovaries. This method allowed adequate numbers of cells to be obtained for the subsequent study involving cyclooxygenase regulation. In a second experiment, bovine granulosa cells from small antral follicles were isolated and cultured as in the first experiment for 6 days. Granulosa cells were then exposed to medium alone or medium containing arachidonic acid (10 …

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Nitrogen Accumulation By Rice., Arthur Bufogle Jr Jan 1996

Nitrogen Accumulation By Rice., Arthur Bufogle Jr

LSU Historical Dissertations and Theses

Consumption of rice is worldwide, and the rice-eating population is expanding rapidly. Breeding high yielding varieties has helped increase rice production. However, effective management practices have also been useful, and will probably become more vital as breeding efforts approach the genetic limits of the rice plant. Nitrogen (N) management is particularly important in reducing N losses and increasing grain yield. The objectives of this study were (1) to determine the amount of N accumulation by rice at different stages of plant development, (2) to determine if differences in N accumulation exist between rice varieties, and (3) to determine if differences …

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The Effect Of Membrane Structure On Lipid Peroxidation And Its Inhibition., Tammy Renee Dugas Jan 1996

The Effect Of Membrane Structure On Lipid Peroxidation And Its Inhibition., Tammy Renee Dugas

LSU Historical Dissertations and Theses

Lipid peroxidation is the process by which lipids in the cell membrane undergo free radical-initiated oxidation. The resulting cell damage has been implicated in the onset of many diseases, including as cancer, aging, and stroke. Lipid oxidation has been studied in a variety of membrane models, including homogeneous solution, micelles, liposomes, and microsomes. The kinetics for free radical reactions proven to occur during lipid oxidation in homogeneous solution have been thoroughly elucidated. These kinetics were also shown to apply to oxidation in micelles. This dissertation presents evidence that the kinetics of more biologically realistic membrane models such as liposomes may …

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Longitudinal Dispersion And Interstitial Velocity Relationship In Subsurface Flow Constructed Wetlands., Gianna M. Cothren Jan 1996

Longitudinal Dispersion And Interstitial Velocity Relationship In Subsurface Flow Constructed Wetlands., Gianna M. Cothren

LSU Historical Dissertations and Theses

Treatment of municipal and rural wastewater using subsurface flow constructed wetlands (SFCW's) is growing in popularity. These systems often consist of an excavated cell containing 2-3 in. rock with the wastewater level maintained below the media surface. A SFCW is a natural form of wastewater treatment which removes organics and nutrients based on the attached growth of microorganisms on crushed rocks where biological reactions take place. The currently accepted design procedure is based on the first order plug flow model, although tracer studies have shown that flow conditions are not well represented by the plug flow condition. This design rationale …

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Relationships Between Brain Biogenic Amines And Reproductive And Defense Behavior In Honey Bees (Apis Mellifera L.)., Jeffrey Wayne Harris Jan 1996

Relationships Between Brain Biogenic Amines And Reproductive And Defense Behavior In Honey Bees (Apis Mellifera L.)., Jeffrey Wayne Harris

LSU Historical Dissertations and Theses

This dissertation represents an attempt to relate behavioral states of worker honey bees to brain levels of biogenic amines. The first chapter describes the results of experiments which indicated that brain levels of octopamine, dopamine and serotonin were affected by factors including the degree of handling stress, worker age, season of sampling and the source colony from which the workers were sampled. These results helped shape the methods employed in the subsequent chapters. The second and third chapters relate changes in brain dopamine levels to worker honey bee ovarian development. In particular, chapter II showed that an increase in brain …

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A Numerical Modeling Study Of The Gulf Of Mexico Under Present And Past Environmental Conditions., Susan Elizabeth Welsh Jan 1996

A Numerical Modeling Study Of The Gulf Of Mexico Under Present And Past Environmental Conditions., Susan Elizabeth Welsh

LSU Historical Dissertations and Theses

The Gulf of Mexico is an ideal location for paleoceanographic study using a three-dimensional ocean circulation model because of the availability of data to verify the model for the present. A description of the Gulf of Mexico circulation during the last glacial maximum is beneficial in interpreting the distribution of glacial fauna and adds to the understanding of global climate change because the Gulf of Mexico is an important link in the circulation of the Atlantic Ocean. The Florida Current originates in the Gulf of Mexico and contributes warm, salty water to the Gulf Stream. The Gulf Stream influences the …

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Conditioning The Auditory System With Continuous Versus Interrupted Noise Of Equal Acoustic Energy: Is Either Exposure More Protective?, Ruth Ann Skellett Jan 1996

Conditioning The Auditory System With Continuous Versus Interrupted Noise Of Equal Acoustic Energy: Is Either Exposure More Protective?, Ruth Ann Skellett

LSU Historical Dissertations and Theses

Prior exposure to moderate-level acoustic stimulation (conditioning) can reduce and/or prevent the deleterious effects of subsequent higher level exposures (Canlon et al., 1988; Campo et al., 1991). Both continuous and interrupted schedules of moderate-level noise have been used as conditioning exposures, and both schedules have been effective in providing protection against subsequent noise trauma. However, there is evidence to suggest that continuous noise exposures are more damaging to the cochlea than interrupted exposures of equal acoustic energy (Bohne et al., 1985, 1987), and moderate-level continuous and interrupted noise exposures differ in the pattern of auditory sensitivity change that they produce …

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Postexercise Hypotension (Peh) In The Dog: Possible Role Of Immune System Cytokines., Gerald Dwayne Thompson Jan 1996

Postexercise Hypotension (Peh) In The Dog: Possible Role Of Immune System Cytokines., Gerald Dwayne Thompson

LSU Historical Dissertations and Theses

This study investigated postexercise hypotension (PEH) in five normotensive dogs testing these hypotheses: (1) PEH is present in the dog model; (2) high intensity exercise of 85% HR$\rm\sb{max}$ as compared to moderate intensity exercise of 60% HR$\rm\sb{max}$ induces a greater PEH; and (3) IL-1 and its activation of PGE$\sb2$ are associated with PEH. In experiment I, it was found that 85% HR$\rm\sb{max}$ exercise decreased systolic blood pressure (SBP) and mean arterial blood pressure (MABP) at 30 and 60 minutes postexercise (p $<$ 0.05). Both IL-1 and PGE$\sb2$ increased immediately following intense exercise, although temporal patterns were dissimilar. During non-exercise infusion of ibuprofen or dexamethasone (experiment II), blood pressure was not affected, but ibuprofen led to an overall inhibition of PGE$\sb2$. However, dexamethasone infusion led to a significant increase in PGE$\sb2$ at 180 and 210 minutes postinfusion. In experiment IIIA, after intense exercise following ibuprofen or saline infusion, PGE$\sb2$ increased at 120 to 180 minutes postexercise. Similar results were noted after exercise during dexamethasone treatment (experiment IIIB). In experiment IIIA & B, neither ibuprofen nor dexamethasone significantly affected PEH, although non-significant reductions in PEH was observed in dexamethasone treated animals. However, PGE$\sb2$ significantly increased after exercise at time points when PEH was not observed. These data indicate that (1) the intensity of exercise may have an effect on PEH, (2) there is partial support for the involvement of IL-1 and PGE$\sb2$ in PEH due to their immediate increase after exercise although a direct relationship was not observed, and (3) IL-1 still remains a possible mechanism responsible for PEH because of trends for attenuated PEH and PGE$\sb2$ responses following dexamethasone treatment.

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An Examination Of The Effects Of The Mother's Education And Household Exposure To Disease On Childhood Diarrheal Morbidity In Sudan., Dawood Hussein Sultan Jan 1996

An Examination Of The Effects Of The Mother's Education And Household Exposure To Disease On Childhood Diarrheal Morbidity In Sudan., Dawood Hussein Sultan

LSU Historical Dissertations and Theses

This dissertation examines the effect of increases in the mother's level of education on the likelihood of diarrheal morbidity among Sudanese children aged 6 to 23 months. Maximum likelihood logistic regression models are used in the analysis. The logit estimates obtained from these models revealed that children of mothers who are illiterate run on average more than 10 times the risk of diarrhea as that run by children to mothers with a senior secondary or higher education. Slight increases in the mother's education, as indicated by an incomplete primary school education, reduce the likelihood of diarrhea by more than 50%. …

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Ion Transport In The Freshwater Bivalve, Corbicula Fluminea (Muller)., Huiyuan Zheng Jan 1996

Ion Transport In The Freshwater Bivalve, Corbicula Fluminea (Muller)., Huiyuan Zheng

LSU Historical Dissertations and Theses

Corbicula fluminea (Muller) maintains hydromineral balance in dilute media by active transepithelial transport of Na and Cl. Cl uptake depended on external (Cl) and displayed saturable kinetics. The transport capacity in pondwater(PW)-acclimated animals was 7.00 $\pm$ 0.51 $\mu$eq(g dry tissue $\cdot$ h)$\sp{-1}$ and the transport affinity 0.21 $\pm$ 0.08 mM. Prolonged salt depletion increased Cl transport capacity without changing the affinity. In PW-acclimated C. fluminea, Na and Cl transport were independent, and were stimulated by serotonin. In salt depleted (SD)animals, Na transport was partially Cl-dependent but Cl transport was Na-independent. Acetazolamide increased Na and Cl efflux. Both serotonin and acetazolamide …

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"Engineered Enjoyment": Technology, Capitalism, And The Female Body In Film., Catherine Williamson Jan 1996

"Engineered Enjoyment": Technology, Capitalism, And The Female Body In Film., Catherine Williamson

LSU Historical Dissertations and Theses

This dissertation explores the link between technology, capitalism, and the female body in 20th century cinema. It argues that commodified pleasure, or "engineered enjoyment," is always produced by establishing technological control over the female body. The scope of this dissertation is limited to films produced during the post-World War II era. In Chapter One I define "engineered enjoyment" and show how film is the prototypical example of such. In Chapter Two I examine how the cinematic apparatus works as a pleasure-producing system and explore what happens when that system breaks down, as in the 1947 film Lady in the Lake. …

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The Association Between Chronic Aerobic Activity And Heart Rate Variability In Patients With Coronary Artery Disease., Robert Howard Wood Jan 1996

The Association Between Chronic Aerobic Activity And Heart Rate Variability In Patients With Coronary Artery Disease., Robert Howard Wood

LSU Historical Dissertations and Theses

Poor heart rate variability (HRV) among patients with coronary artery disease (CAD) is predictive of future incidence of sudden arrhythmic and all-cause death. Furthermore, mental stress appears to further depress HRV in these patients. Chronic aerobic activity level appears to be positively related to HRV among the general population; however, the extent to which this relationship exists among patients with CAD is not clear. Therefore, this study investigated the association between level of chronic aerobic activity and HRV among CAD patients during conditions of paced respiratory control and during the Stroop Color-Word Conflict Test (CWCT). CAD patients were assigned to …

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Cytogenetic And Molecular Analysis Of The Channel Catfish (Ictalurus Punctatus) Genome., Quiyang Zhang Jan 1996

Cytogenetic And Molecular Analysis Of The Channel Catfish (Ictalurus Punctatus) Genome., Quiyang Zhang

LSU Historical Dissertations and Theses

This research presents studies on cytogenetics and molecular genetics of channel catfish (Ictalurus punctatus), the most important fish species cultured in the United States. The goals of this project were to analyze the genome of the channel catfish and to develop a direct method of mapping single-locus genes. A series of techniques were developed to facilitate these studies, including culture of fibroblast cells, preparation of chromosomes from catfish of different ages, staining for nucleolus organizer regions (NOR) and heterochromatin (C-banding), restriction enzyme banding, replication R-banding, simultaneous detection of sister-chromatid exchange (SCE) and C-banding, fluorescent in-situ hybridization (FISH) and indirect and …

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Microsatellite-Based Paternity Analysis In Hexaploid Sweetpotato (Ipomoea Batatas (L.) Lam.)., Mario Ignacio Buteler Jan 1996

Microsatellite-Based Paternity Analysis In Hexaploid Sweetpotato (Ipomoea Batatas (L.) Lam.)., Mario Ignacio Buteler

LSU Historical Dissertations and Theses

The use of genetic markers for paternity identification was investigated in hexaploid sweetpotato. Traditional sweetpotato breeding relies on the open pollination of numerous parents and the visual selection of progeny. Previous empirical and theoretical evidence shows this type of breeding system is extremely inefficient. Typically, only a few of these maternal parents routinely produce superior progeny. A similar scenario exists for the paternal parent. Identifying specific parental combinations which produce superior progeny would improve breeding efficiency, hence the need to identify paternity in superior progeny. A computer simulation study established the minimum number of alleles and loci required for paternity …

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A Physiological Study Of Common Carpetgrass (Axonopus Affinis) Subjected To Cultural And Environmental Stress., Edward Wayne Bush Jan 1996

A Physiological Study Of Common Carpetgrass (Axonopus Affinis) Subjected To Cultural And Environmental Stress., Edward Wayne Bush

LSU Historical Dissertations and Theses

Common carpetgrass (Axonopus affinis Chase) is a low maintenance stoloniferous grass widely distributed throughout the southern coastal plains of the United States. This study investigated seed germination enhancement, seedhead suppression, waterlogging tolerance, winter hardiness, and maintenance practices for common carpetgrass. Pre-soaking common carpetgrass and centipedegrass (Eremochloa ophiuroides (Munro.) Hack.) seed was beneficial at the 30C germination temperature. Priming seed in KNO$\sb3$ solutions significantly accelerated seed germination of both centipedegrass and carpetgrass at 30C, and increased total germination percentage of centipedegrass. At 20 and 25C, seed priming significantly improved mean time of germination for both grass species and total germination percentage …

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Wordsworth's Mother Tongue: Identification, Separation, And Recognition., Robert C. Hale Jan 1996

Wordsworth's Mother Tongue: Identification, Separation, And Recognition., Robert C. Hale

LSU Historical Dissertations and Theses

This psychoanalytic study complicates prevailing notions about William Wordsworth's representations of mothers. Wordsworth does not invariably conflate mothers with Nature or consistently construct women as silent objects of male quest. Rather, he explores a variety of mothers' voices, often associating them with language acquisition and poetic composition. In early work he acknowledges mothers' significance directly and creates more vocal mothers, while in later work and revisions he often conceals mothers' significance and depicts more object-like mothers. In the 1805 version of book two of The Prelude, Wordsworth recalls himself as a "blessed babe" who recognizes his mother as a separate …

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Movements, Habitat Use, And Survival Of Female Northern Pintails In Southwestern Louisiana., Robert Ripley Cox Jr Jan 1996

Movements, Habitat Use, And Survival Of Female Northern Pintails In Southwestern Louisiana., Robert Ripley Cox Jr

LSU Historical Dissertations and Theses

I developed portable platforms for setting rocket nets in open-water habitats, and used them to capture 1116 waterfowl of 7 species during winters 1991-92 and 1992-93 in southwestern Louisiana. Distance and duration of evening flights of female northern pintails (Anas acuta; hereafter pintails) from Lacassine National Wildlife Refuge increased with date within wintering period, and generally were greater than previously reported estimates for wintering waterfowl. I found that diurnal use of refuges by females increased during hunting seasons, contradicting Tamisier's hypothesis that use of refuges by pintails in southwestern Louisiana is not influenced by hunting. Female pintails extensively used privately …

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Immobilization Of P. Digitatum And Bioconversion Of Limonene To Alpha-Terpineol., Qiang Tan Jan 1996

Immobilization Of P. Digitatum And Bioconversion Of Limonene To Alpha-Terpineol., Qiang Tan

LSU Historical Dissertations and Theses

The parameters of bioconversion of limonene to $\alpha$-terpineol by Penicillium digitatum were determined. This bioconversion was carried out stereo-specifically and selectively by this fungus. (R)-(+)-limonene was selectively converted to (R)-(+)-$\alpha$-terpineol by mycelia of this fungus during early growth phase. Immobilization of the fungal mycelia for use in continuous production of this product was possible. Aeration was critical to this bioconversion. The optimum aeration was about 1.6 mg/L for growing cells and immobilized cells. Substrate inhibition of the bioconversion was not observed when the substrate concentration was below 4% (v/v). End product inhibition was observed. The $\rm Ki\sb{app}$ was 12.08 mM. …

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The Moderating Effect Of Combinations Of Dissimilar Shoppers' And Sellers' Ethnicities On A Model Of Dyadic Sales Encounters: Shoppers' Perceptions Of Ethnically Different Retail Salespersons., Andrew D. Banasiewicz Jan 1996

The Moderating Effect Of Combinations Of Dissimilar Shoppers' And Sellers' Ethnicities On A Model Of Dyadic Sales Encounters: Shoppers' Perceptions Of Ethnically Different Retail Salespersons., Andrew D. Banasiewicz

LSU Historical Dissertations and Theses

An empirical assessment of the moderating effect of combinations of ethnically dissimilar shoppers and sellers on the nature of retail sales encounters is undertaken. Following the similarity-attraction paradigm (Bochner 1982; Byrne 1961), it is theorized that ethnically similar shoppers and sellers are more attracted to each other than ethnically dissimilar ones, resulting in shoppers' perceptions of sellers' behaviors and personality traits being adversely effected. Operationally, the entire model of sales encounters is moderated by combinations of ethnically dissimilar shoppers and sellers (global moderation hypothesis), or dyadic ethnic dissimilarity. A 2 x 2 experimental design is employed, with the levels of …

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Biochemical And Biophysical Studies Of Wild-Type And Active-Site Mutants Of Human Adenosine Deaminase., Qing Zeng Jan 1996

Biochemical And Biophysical Studies Of Wild-Type And Active-Site Mutants Of Human Adenosine Deaminase., Qing Zeng

LSU Historical Dissertations and Theses

The focus of this work is structural and functional studies of wild-type and active-site mutants of human adenosine deaminase. Two active-site amino acids, Glu217 and His238, were previously substituted with alanine by site-directed mutagenesis. The Glu217Ala and His238Ala mutants showed little or no changes in Zn content and $\rm K\sb{m}$ value, yet dramatic loss of enzyme activity. Circular dichroism studies of the solution conformation of wild-type and mutant human adenosine deaminases indicate that 30 to 50% of $\alpha$-helical structure is lost in Glu217Ala and His238Ala, respectively, whereas $\beta$-sheet structure is fully retained. Inhibitor binding is measured by a fluorescent assay. …

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Women Who Lead High Schools: A Missing Element In Leadership Theory., Kristy Brock Hebert Jan 1996

Women Who Lead High Schools: A Missing Element In Leadership Theory., Kristy Brock Hebert

LSU Historical Dissertations and Theses

I addressed the problem that leadership theory is lacking in regard to how women lead high schools. My primary purpose was to contribute to the limited literature that exists regarding the leadership practices of women who are high school principals. I explored the notion of a female culture of school leadership and situated that culture among quintessential theory dictated by organizational research. I conducted this study in two phases. In Phase One I reported the demographics of 44 female high school principals in Louisiana along with their self-reported values on 32 leadership characteristics. Most important to their leadership were: communication, …

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Foraging Behavior And Habitat Selection Of Insectivorous Migratory Songbirds At Gulf Coast Stopover Sites In Spring., Chao-Chieh Chen Jan 1996

Foraging Behavior And Habitat Selection Of Insectivorous Migratory Songbirds At Gulf Coast Stopover Sites In Spring., Chao-Chieh Chen

LSU Historical Dissertations and Theses

Abundance of some species of Nearctic-Neotropical migrants has been declining dramatically since 1970. Most literature about Neotropical migrants is from the breeding grounds, and some is from the wintering grounds; very little is from stopover sites. I studied foraging behavior and habitat selection of insectivorous migratory songbirds at three stopover sites along northern coast of the Gulf of Mexico during spring migrations of 1993-1995. Each migrant species had its unique combination of foraging behavior and habitat use during stopover. Migrants selected certain habitat strata and plant species and avoided others. The decrease of understory vegetation in the reduced plots had …

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Mechanism Of Nitrogen Fixation: Use Of Carbon Monoxide To Probe Nitrogenase Activity., Linda Margaret Cameron Jan 1996

Mechanism Of Nitrogen Fixation: Use Of Carbon Monoxide To Probe Nitrogenase Activity., Linda Margaret Cameron

LSU Historical Dissertations and Theses

The inhibitor CO was used to investigate the mechanism of Mo and V nitrogenase. While low pressures of CO enhanced, high pressures inhibited V nitrogenase-catalyzed C$\rm\sb2H\sb6$ formation. This is not the case for $\rm C\sb2H\sb4$ formation, where the rate of electron flux determined if CO acted as an enhancer or inhibitor. A two-site model is proposed, in which CO binding to one site enhances, and CO binding to both sites inhibits product formation. Replacement of CO(g) by Ar or $\rm C\sb2H\sb2$ resulted in correlated decay of hi-CO and development of lo-CO EPR signals, suggesting that the two signals arise from …

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Synthesis Of Novel Amino Acids With Incorporation Into Peptides And Synthesis Of Peptides With Novel Aggregation States., Scott Michael Cowell Jan 1996

Synthesis Of Novel Amino Acids With Incorporation Into Peptides And Synthesis Of Peptides With Novel Aggregation States., Scott Michael Cowell

LSU Historical Dissertations and Theses

Peptides exhibit properties based on the amino acids present in the peptide and structure the peptide assumes in its environment. For example, peptides have been shown to be antimicrobial when they are amphipathic and in an $\alpha$-helical shape. The mechanism for this antimicrobial activity is subject to dispute. One theory states that the peptides work by forming a "pore" through the cell membrane which causes a depolarization of the membrane and the cell lysis because of osmosis. Another theory states that the peptides merely compromise the integrity of the membrane by solubilizing the membrane. In order for the "pore" theory …

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Low Carbon Dioxide-Inducible Genes And Proteins In Chlamydomonas Reinhardtii., Zhi-Yuan Chen Jan 1996

Low Carbon Dioxide-Inducible Genes And Proteins In Chlamydomonas Reinhardtii., Zhi-Yuan Chen

LSU Historical Dissertations and Theses

At low CO$\sb2$ conditions, C. reinhardtii, like many other green algae, induces a CO$\sb2$ Concentrating Mechanism (CCM) to raise the internal Ci concentration. During the induction, at least five new polypeptides and six different genes are upregulated and some of the corresponding mRNAs or proteins are absent in high CO$\sb2$ requiring mutants. However the identities and functions of these genes are unknown. In this dissertation, I partially characterized four low CO$\sb2$ inducible genes and one low CO$\sb2$ inducible protein LIP-36. The complete cDNA sequences of clones 11I3 and 2I5 are 1311 bp and 985 bp, respectively. Neither of these two …

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Genetic Components Of (Co)Variance For Postweaning Growth, Carcass Composition And Meat Quality Traits Among Brahman-Influenced Beef Steers., D. H. Denny Crews Jr Jan 1996

Genetic Components Of (Co)Variance For Postweaning Growth, Carcass Composition And Meat Quality Traits Among Brahman-Influenced Beef Steers., D. H. Denny Crews Jr

LSU Historical Dissertations and Theses

A genetic analysis was conducted on preweaning and postweaning growth and carcass composition records from steers produced in two long-term crossbreeding studies. In phase I, Angus (A), Brahman (B), Brangus (BR), Charolais (C) and Hereford (H) sires produced straightbred, F$\sb1$, back-cross, three-breed cross and 2- and 3-breed rotational crossbred steers (N = 708) from 1960 to 1968. Straightbred, F$\sb1$, back-cross, three-breed cross and 2-, 3- and 4-breed rotational crossbred steers (N = 1530) were produced from 1970 to 1988 by A, B, C and H sires in phase II. Direct and maternal additive and non-additive genetic effect contrasts were obtained. …

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Reduction And Management Of Vibrio Vulnificus In Gulf Coast Oyster (Crassostrea Virginica)., Yu-Pin Chen Jan 1996

Reduction And Management Of Vibrio Vulnificus In Gulf Coast Oyster (Crassostrea Virginica)., Yu-Pin Chen

LSU Historical Dissertations and Theses

The AmeriPure Process (AmeriPure Oyster Company, New Orleans, Louisiana), which is a mild heat treatment for a specific time period, proved effective in eliminating Vibrio vulnificus from the Gulf Coast oysters (Crassostrea virginica), thus reducing the risk of possible V. vulnificus infections. The treatment was effective in the reduction of V. vulnificus in both $1.5\times10\sp5$ MPN/g (high artificially contaminated level) and $2.4\times10\sp3$ MPN/g (low artificially contaminated level) to undetectable level (MPN $<$ 3/g). The mild heat treatment also reduced naturally occurring V. vulnificus $(8.9\pm3.7\times10\sp4$ MPN/g) present in shellstock oysters harvested in warmer months to undetectable levels. The D value for V. vulnificus present in shellstock oyster averaged 45.6 $\pm$ 3.3 seconds at the AmeriPure Process temperature. Mild heat treatment can also control aerobic plate count numbers during refrigerated storage (0-2$\sp\circ$C) and extend the shelf-life of raw oysters for at least 7 days over unprocessed samples. Mild heat treated oysters need to be refrigerated (${<}4\sp\circ$C) to ensure the safety and quality, as well as shelf-life. Oysters treated according to the AmeriPure Process when exposed to an average room temperature of 27$\sp\circ$C were found unacceptable after 24 hours due to the high number of aerobic plate count (10$\sp7$ CFU/g) and were considered not safe to eat. Although there was a slight lightening in color, sensory panels, composed of both traditional raw oyster consumers and infrequent consumers, found the treated product to be comparable in flavor, texture and smell to untreated oysters. According to the result of sensory evaluation, the good oyster flavor of treated samples increased and the off-flavor and off-odor of the treated oysters were significantly lower than the control samples after 7 days of storage on ice. Possible temperature variations, which could occur during the transportation and storage were studied in a temperature abuse study. The result showed that no Vibrio vulnificus was recovered and no significant microbiological quality change was observed after 10 hours of exposure to the room temperature of $22\pm2\sp\circ$C.

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