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Role Of Curved Dna In Promoter Recognition With Bacillus Subtilis And Escherichia Coli Rna Polymerase., Cheryl Anne Nickerson
Role Of Curved Dna In Promoter Recognition With Bacillus Subtilis And Escherichia Coli Rna Polymerase., Cheryl Anne Nickerson
LSU Historical Dissertations and Theses
Intrinsically curved DNA upstream of the RNA polymerase binding site, the promoter, influences transcription in Bacillus subtilis. In this study, curved DNA upstream of the $-$35 region was examined for the ability to influence transcription in Escherichia coli and B. subtilis through the use of hybrid promoters. These promoters were constructed by substituting the curved DNA from two B. subtilis promoters, Bal129 and Alu156, for the DNA upstream of the $-$35 region in the lambda phage promoters $p\sb{\rm R}$ and $p\sb{\rm L}$. The hybrid promoters were designated Bal$p\sb{\rm R}$, Alu$p\sb{\rm R}$, Bal$p\sb{\rm L}$, and Alu$p\sb{\rm L}$. Using transcriptional fusions between …
Pharmacodynamics Of Non-Steroidal Anti-Inflammatory Agents In Acute Inflammation And Chronic Pain In The Horse., Jane Granville Owens
Pharmacodynamics Of Non-Steroidal Anti-Inflammatory Agents In Acute Inflammation And Chronic Pain In The Horse., Jane Granville Owens
LSU Historical Dissertations and Theses
The analgesic and anti-inflammatory effects of the nonsteroidal anti-inflammatory drugs (NSAIDs) ketoprofen (2.2 and 3.63 mg/kg) and phenylbutazone (4.4 mg/kg) were compared in equine models of acute synovitis and chronic hoof pain. The eicosanoids, prostaglandin E$\sb2$ (PGE$\sb2$) and leukotriene B$\sb4$ (LTB$\sb4$), increased dramatically in synovial fluid after carrageenan-induced synovitis of the intercarpal joint. PGE$\sb2$ concentrations in untreated horses peaked at 9 hours while LTB$\sb4$ concentrations peaked in all horses at 3 hours. Synovial fluid concentrations of both eicosanoids returned to near baseline by 48 hours. Lameness, joint temperature, and synovial fluid volume, protein and nucleated cells increased at 3 to …
The Production And Characterization Of Alginate Produced By Pseudomonas Syringae., Richard David Ashby
The Production And Characterization Of Alginate Produced By Pseudomonas Syringae., Richard David Ashby
LSU Historical Dissertations and Theses
Alginate has many industrial uses because of its unique colloidal behavior, and its ability to thicken, stabilize, emulsify, suspend, form films, and produce gels. Currently, all commercial alginate comes from brown algae, where it exists naturally as a structural material. Many different types of brown algae produce alginate but it can only be obtained in sufficient quantity and quality from a limited number of species. On the basis of location, at least half of the world's resources of this polymer are potentially at risk due either to political instability or industrial pollution. Bacteria provide a potentially unlimited alternate source for …
Factors Affecting Sediment Transport, Deposition And Erosion In Intertidal Wetlands In Louisiana., Roelof Maria Boumans
Factors Affecting Sediment Transport, Deposition And Erosion In Intertidal Wetlands In Louisiana., Roelof Maria Boumans
LSU Historical Dissertations and Theses
Processes leading to land loss in Louisiana are defined, measured and analyzed with special emphasis on the deposited and suspended sediment budgets. The findings were used to assess coastal management in Louisiana. In a spatial model of long term habitat succession, the degradation of a Louisiana wetland was based upon simulated exchanges of sediments across irregularly shaped polygons. Habitat distribution within a cell was estimated by elevation. The model findings were confirmed when the impact of two Louisiana marsh management plans caused reduced short-term sedimentation due to impaired water and materials flux. The sedimentation-erosion table (SET) is described and applied …
Tolerance Potential And Defense Mechanisms Of Honey Bees (Apis Mellifera L.) To Varroa Jacobsoni Oud. (Acari: Varroidae) And Acarapis Species (Acari: Tarsonemidae)., Lilia Ibay De Guzman
Tolerance Potential And Defense Mechanisms Of Honey Bees (Apis Mellifera L.) To Varroa Jacobsoni Oud. (Acari: Varroidae) And Acarapis Species (Acari: Tarsonemidae)., Lilia Ibay De Guzman
LSU Historical Dissertations and Theses
Comparative resistance or tolerance of four stocks of Apis mellifera L. to Varroa jacobsoni Oudemans, Acarapis dorsalis Morgenthaler, Acarapis externus Morgenthaler and Acarapis woodi (Rennie), was investigated using choice (bioassay) and field experiments. A. m. carnica from Yugoslavia (ARS-Y-C-1), A. m. carnica from Canada (Hastings), F$\sb1$ hybrid between ARS-Y-C-1 and Hastings and a general Louisiana stock were evaluated. A tolerance index showed that Hastings, ARS-Y-C-1 and F$\sb1$ hybrid exhibited some degree of tolerance to V. jacobsoni. These stocks lived longer with higher levels of Varroa infestation in worker pupae and on adult honey bees. Louisiana stock was more susceptible to …
Seasonal And Spatial Abundance And Size Distribution Of Fishes Associated With A Petroleum Platform In The Northern Gulf Of Mexico., David Robert Stanley
Seasonal And Spatial Abundance And Size Distribution Of Fishes Associated With A Petroleum Platform In The Northern Gulf Of Mexico., David Robert Stanley
LSU Historical Dissertations and Theses
The purpose of this study was to demonstrate the utility of dual-beam hydroacoustics in measuring abundance and target strength of fishes near a petroleum platform in the northern Gulf of Mexico. From September to November 1990 fish densities ranged from 0 to 1.88 fish/m$\sp3$ and varied with platform side, depth, time of day and month. Densities were highest adjacent to the platform and decreased significantly beyond 9 m. Approximately 2,400 to 8,300 fish were associated with the platform depending on month. Target strengths ranged from $-$56 to $-$24 dB and varied with side of the platform and month. Mean monthly …
Immunological And Developmental Factors Affecting The Efficacy Of In Vitro Fertilization, Embryo Culture And Embryo Transfer In The Domestic Cat., William Frederick Swanson
Immunological And Developmental Factors Affecting The Efficacy Of In Vitro Fertilization, Embryo Culture And Embryo Transfer In The Domestic Cat., William Frederick Swanson
LSU Historical Dissertations and Theses
Developmental and immunological factors affecting the efficacy of assisted reproduction for domestic and endangered nondomestic felid species were investigated. In the first study, domestic cats exhibited decreased (P $<$ 0.05) numbers of follicles and maturity of oocytes following repeated treatments, at short intervals (44-50 days), with a combination regimen of equine chorionic gonadotropin (eCG) and human chorionic gonadotropin (hCG). Queens had elevated titers of eCG/hCG-binding immunoglobulins compared with male cats and naive queens, and these immunoglobulins attenuated eCG and hCG bioactivity in mouse ovarian stimulation assays. However, refractory queens appeared to cycle naturally and were responsive to an alternative exogenous gonadotropin, porcine follicle stimulating hormone (pFSH). In the second study, queens exhibited individual variability in immune responses to eCG and hCG, and this variability affected (P $$ 0.05) when longer intervals (130-135 days) were used between successive eCG/hCG treatments. In the third study, the effects of eCG and hCG on the suitability of the maternal environment were investigated. Following intramuscular injection, eCG had an elimination half-life of 24 to 48 hours and, 5 and 15 days after follicular aspiration, eCG/hCG-treated queens had formed multiple ancillary follicles and secondary corpora lutea (CL), respectively. Treatment with antisera against eCG/hCG slowed (P $$ 0.05) serum progesterone levels or decrease (P $>$ 0.05) the number of secondary ovarian structures. In the fourth study, developmental requirements of IVF-derived cat embryos were examined, with the emphasis on energy sources, media complexity and tissue co-culture and temporal variations in these factors. Embryos developed equally well (P $>$ 0.05) to morulae in simple media containing either glucose or glutamine, but blastocyst formation and embryo cell number were decreased (P $<$ 0.05) when glucose was present during the early culture period. Co-culture of embryos on oviductal cell monolayers decreased (P $<$ 0.05) fertilization and blastocyst formation. In the final study, a transcervical technique for embryo transfer was developed and used successfully to produce viable offspring in the domestic cat.
Interactions Of The Soybean Looper, Pseudoplusia Includens (Walker), And Soybean, Glycine Max (L.) Merrill, Involving Nitrogen: Effects On Host Symbiotic Nitrogen Fixation And Larval Development And Survival., Alan Thomas Wier
LSU Historical Dissertations and Theses
Acetylene reduction and nitrogen difference assays were used to evaluate effects of defoliation by soybean looper, Pseudoplusia includens (Walker), during reproductive growth stages on symbiotic nitrogen fixation by soybean. Defoliation (50-55%) of group VI cultivar Lee from full bloom into pod development stages caused up to 85% reduction of nitrogenase activity, whereas lower defoliation levels (32%) during seed development did not affect nitrogenase activity. Defoliation (74-94%) of group IV cultivar Clark caused 80-100% reduction of nitrogenase activity, regardless of whether defoliation occurred during bloom and pod development or during seed development. The nitrogen difference assay identified a reduction in the …
Elevation Of The Hatching Envelope In Penaeidea Shrimp: Morphology And Assembly., Patricia Stoops Glas
Elevation Of The Hatching Envelope In Penaeidea Shrimp: Morphology And Assembly., Patricia Stoops Glas
LSU Historical Dissertations and Theses
The appearance of extracellular coats around "eggs" are associated with activation of the oocytes. This coat, termed fertilization envelope (sea urchins), chorion (fish), zona pellucida (mammals), capsule (crab) or hatching envelope (HE) (shrimp) serves as a polyspermy block (Wasserman, 1982) or microenvironment protecting the egg from bacteria or other hostile elements (Kudo and Inoue, 1989; Kudo and Teshima, 1991; Kudo, 1992; Epel, 1993). HE assembly is described for penaeoid shrimp (Lynn, et al., 1991) and is, in contrast to many systems, a fertilization independent event. However, the mechanisms of assembly appear similar to extracellular coat formation in other animal systems …
The Role Of Infaunal And Epifaunal Suspension Feeding Macrofauna On Rates Of Benthic-Pelagic Coupling In A Southeastern Estuary., Christine Miller-Way
The Role Of Infaunal And Epifaunal Suspension Feeding Macrofauna On Rates Of Benthic-Pelagic Coupling In A Southeastern Estuary., Christine Miller-Way
LSU Historical Dissertations and Theses
This research investigated the effects of two suspension feeding bivalves, the infaunal Rangia cuneata, and the epifaunal Crassostrea virginica, on benthic-pelagic coupling in Fourleague Bay, LA, a river-dominated estuary. A continuous-flow microcosm system was developed to overcome recognized limitations of batch methodology and to facilitate manipulations designed to investigate the ecological role of benthic macrofauna. Experiments comparing traditional batch methodology to continuous-flow methodology indicated that rates of benthic processes were consistently greater when measured using continuous-flow methodology. Examinations of concentrations indicated that differences were due to concentration gradients which departed from ambient over time in the batch cores. Over an …
Promoter Analysis Of A Rice Seed Storage Protein Glutelin Gene And Expression Of Bean 7s Seed Storage Protein Beta-Phaseolin In Transgenic Rice Plants., Zhenwei Zheng
LSU Historical Dissertations and Theses
It was demonstrated, using a homologous transgenic rice system, $5\sp\prime$ distal and proximal cis-acting transcriptional regulatory elements were required for developmental control of a rice seed storage protein glutelin (Gt1) gene. The functional importance of proximal elements in the context of the 1.8 kb promoter was demonstrated by single substitution mutations in the TATA box ($-$28/$-$23), AACA motif ($-$73/$-$61), and protein-binding Boxes I ($-$103/$-$86), II ($-$124/$-$110), III ($-$175/$-$158), and IV ($-$200/$-$217). A simultaneous mutation of five protein-binding sites ($-$410/$-$86) essentially eliminated the activity of the 1.8 kb promoter. To understand the function of the $5\sp\prime$ distal cis-acting upstream sequence, eighteen …
Demographic And Genetic Studies Of Seed Dispersal And Juvenile Survival In An Old-Growth Longleaf Pine Population., Susan Langevin Grace
Demographic And Genetic Studies Of Seed Dispersal And Juvenile Survival In An Old-Growth Longleaf Pine Population., Susan Langevin Grace
LSU Historical Dissertations and Theses
Many biotic and abiotic factors contribute to the formation of aggregations of seedlings and juveniles in populations of forest trees. The following studies investigate factors influencing the spatial structure of juveniles in an old-growth longleaf pine (Pinus palustris Mill.) population. In the first study, effects of adult tree density, pine needle litter and fire temperature were related to the demography of juveniles. A cohort of juveniles from a mast year in 1987 was followed over four years. Demographic components were determined both before and up to two years after fire. Juveniles were more dense, larger and had higher survival in …
Electrophysiological Responses Of Olfactory Receptor And Bulb Neurons To Stimulus Mixtures And To Their Individual Components In The Channel Catfish, Ictalurus Punctatus., Jiesheng Kang
LSU Historical Dissertations and Theses
Both electro-olfactogram and integrated multiunit receptor responses of populations of olfactory receptor neurons (ORNs) clearly showed that responses to complex mixtures were predictable. Results demonstrated that receptor sites for basic and acidic amino acids, respectively, are independent from those for neutral amino acids and multiple receptor site types with highly overlapping specificities exist for amino acids within each group. Results also confirmed that one mechanism for synergism is the simultaneous activation of relatively independent receptor sites by the components in a mixture, and there was no evidence of mixture suppression. Single ORNs recorded in vivo responded to stimuli with either …
Epidemiology Of Strongylate Nematode And Coccidia (Eimeria) Infection In Sheep With Special Reference To Breed Resistance., Mahesan Bahirathan
Epidemiology Of Strongylate Nematode And Coccidia (Eimeria) Infection In Sheep With Special Reference To Breed Resistance., Mahesan Bahirathan
LSU Historical Dissertations and Theses
In the United States, the annual production losses in small ruminants due to internal parasites has been estimated at $45 million. In 1992, 1993 and 1994, breed specific responses to naturally acquired strongylate nematode and coccidia ({\it Eimeria\/}) infections were compared in three classes (suckling lambs, weaned lambs, and mature ewes) of pure-bred Suffolk and sheep native to Louisiana (Native) which were grazed together on infective pasture. Parasitological (fecal egg counts and nematode counts) and hematological (packed cell volumes, total immunoglobulin levels, total and class-specific anti-{\it Haemonchus contortus\/} antibody levels and eosinophil counts) data were collected. In suckling Native lambs, …
Effects Of Nandrolone Decanoate On Strength, Markers Of Bone Formation And Turnover In Obese Postmenopausal Women With Normal Bone Density., Ellen Rose Brooks
Effects Of Nandrolone Decanoate On Strength, Markers Of Bone Formation And Turnover In Obese Postmenopausal Women With Normal Bone Density., Ellen Rose Brooks
LSU Historical Dissertations and Theses
Treatment with androgens and anabolic steroids in conditions of high bone turnover seen in osteoporotic postmenopausal females has resulted in bone density improvement. Research has demonstrated a link between muscle mass and bone due to the mechanical demands placed on bone by muscular contractile force associated with physical activity. This study examined whether treatment with a synthetic anabolic steroid, 30 mg. of nandrolone decanoate every two weeks, or placebo increased lean mass, cross-sectional area of thigh muscle and muscle torque production while preserving bone mineral density (BMD) in 18 dieting, sedentary, obese, postmenopausal females not on estrogen replacement therapy. Obesity …
Evolutionary Patterns In Proteaceae Based On Comparative Floral And Inflorescence Ontogenies., Andrew William Douglas
Evolutionary Patterns In Proteaceae Based On Comparative Floral And Inflorescence Ontogenies., Andrew William Douglas
LSU Historical Dissertations and Theses
Comparative floral and inflorescence ontogenies among Proteaceae are examined and a phylogenetic analysis based on principles of parsimony is presented. Comparative developmental and morphological investigations indicate that the fourmerous flowers are primitively simple. Each flower is composed of: a single series of four tepals that are initiated in two dimerous whorls (in most taxa); four stamens, each one initiated opposite a tepal and generally fused to the tepal at various heights due to zonal growth; and a single carpel. Ontogenetic studies reveal that the nectaries arise late in development and are not homologous to a reduced petal or stamen whorl. …
Life History Responses To Fire Season In A Clonal Herb, Pityopsis Graminifolia (Asteraceae)., John Stephen Brewer
Life History Responses To Fire Season In A Clonal Herb, Pityopsis Graminifolia (Asteraceae)., John Stephen Brewer
LSU Historical Dissertations and Theses
The effects of three fire seasons (May, August, and January) on reproductive success and clonal growth of a golden aster (Pityopsis graminifolia) were examined within experimental burn plots in a longleaf pine savanna in north Florida. Several factors influenced reproductive success in this species, including rates of floral induction and bud herbivory, clone fecundity, and seedling dynamics. Flowering was induced by fire, especially when it occurred in May or August. Fire season affected rates of floral induction and bud herbivory by as much as one to two orders of magnitude. Sizes of bolting shoots were also affected by fire season. …
Investigations On Insecticide Resistance In Tobacco Budworm, Heliothis Virescens (F.), And Boll Weevil, Anthonomus Grandis Grandis Boheman, In The Mid-South., Scott Hamilton Martin
Investigations On Insecticide Resistance In Tobacco Budworm, Heliothis Virescens (F.), And Boll Weevil, Anthonomus Grandis Grandis Boheman, In The Mid-South., Scott Hamilton Martin
LSU Historical Dissertations and Theses
Topical bioassays were conducted in 1991 to develop dose-mortality lines for the LSU laboratory reference colony (LSU-LAB) and field-collected colonies of tobacco budworm, Heliothis virescens (F.), from Louisiana, Mississippi and Texas. Field-collected colonies exhibited resistance to cypermethrin (1-41x), profenofos and sulprofos (1-8x), methomyl (2-6x) and no resistance to endosulfan compared to the LSU-LAB colony. Diagnostic dose bioassays were developed to facilitate rapid testing of field-collected colonies for resistance to insecticides. These diagnostic dose bioassays were conducted in 1992 and 1993 on the LSU-LAB colony, a North Carolina laboratory reference colony and field-collected colonies from Louisiana, Oklahoma and Texas. Significant (P …
Latitudinal Gradients In Temperate And Tropical Seasonal Forests., Martin Francis Quigley
Latitudinal Gradients In Temperate And Tropical Seasonal Forests., Martin Francis Quigley
LSU Historical Dissertations and Theses
In an analysis of latitudinally replicated one hectare samples, nine seasonal forests of the temperate and tropical Americas were found to be very similar in biomass, stratification and patterns of spatial dispersion, regardless of taxonomic composition or relative stem density. Neither basal area nor relative size class distributions of trees differed significantly among latitudes from the equator to 40$\sp\circ$ north. While overall plant density was greater in tropical forests, the numbers and composition within individual strata--shrub layer, subcanopy, canopy, and liana--interacted independently and significantly with latitude. Understory populations were denser and more speciose at middle latitudes, in forests frequently affected …
Permethrin Resistance In The Soybean Looper, Pseudoplusia Includens (Walker): Geographic Variation, Mechanisms, Inheritance, And Host Plant Effects., James Donald Thomas Jr
Permethrin Resistance In The Soybean Looper, Pseudoplusia Includens (Walker): Geographic Variation, Mechanisms, Inheritance, And Host Plant Effects., James Donald Thomas Jr
LSU Historical Dissertations and Theses
Field strains of soybean looper, Pseudoplusia includens (Walker), from Louisiana, Texas, and Puerto Rico were tested for permethrin synergism by piperonyl butoxide (PB) and S,S,S tributylphosphorotrithioate (DEF). Resistance was completely suppressed by 10 $\mu$g PB/larva in strains from Louisiana with 2.7 to 14.1-fold resistance. The Texas strain was 14.8-fold resistant and permethrin toxicity was increased 8.6-fold by PB. The Puerto Rico strain was highly resistant to permethrin (426.6-fold) and PB increased permethrin toxicity only 4.6 and 7.5-fold, respectively, at 10 and 20 $\mu$g/larva. No significant synergism resulted from DEF treatment in any of the strains tested. In field trials, efficacy …
Host Plant Adaptation In The Two Strains Of Fall Armyworm (Lepidoptera: Noctuidae)., Klaas H. Veenstra
Host Plant Adaptation In The Two Strains Of Fall Armyworm (Lepidoptera: Noctuidae)., Klaas H. Veenstra
LSU Historical Dissertations and Theses
The fall armyworm (Spodoptera frugiperda J. E. Smith) Lepidoptera: Noctuidae) consists of two genetically differentiated strains. The corn strain feeds on corn and the rice strain feeds primarily on rice and forage grasses. My research focused on host plant adaptations within each strain as assessed by larval performance and enzymatic responses to feeding upon different hosts. Three sets of experiments were conducted. The first experiment examined consumption and utilization in both strains reared on corn. In the second experiment, mixed-function oxidase (MFO) and general esterase enzyme activities were measured from larvae of both strains that were reared on corn, bermudagrass, …
Sedimentation Processes In Selected Coastal Wetlands From The Gulf Of Mexico And Northern Europe., John Charles Callaway
Sedimentation Processes In Selected Coastal Wetlands From The Gulf Of Mexico And Northern Europe., John Charles Callaway
LSU Historical Dissertations and Theses
Sediment cores were collected from coastal wetlands from the Gulf coast of North America and northern Europe to study accretion rates and heavy metal accumulation. There was a significant decrease in vertical accretion rates from low to high marsh for Gulf coast samples. Contrary to previous results, these low tidal range sites did not have negative accretion balances. Northern European samples demonstrated the utility of Chernobyl $\sp{137}$Cs as a sediment marker. There were large differences in sediment characteristics and accretion rates between Polish and western European samples. Vertical accretion rates based on $\sp{210}$Pb were lower than $\sp{137}$Cs rates for most …
Transcriptional Cis-Regulatory Elements And Trans-Factors Of A Gene For The Seed Storage Protein Beta-Phaseolin From Common Bean (Phaseolus Vulgaris)., Yasushi Kawagoe
Transcriptional Cis-Regulatory Elements And Trans-Factors Of A Gene For The Seed Storage Protein Beta-Phaseolin From Common Bean (Phaseolus Vulgaris)., Yasushi Kawagoe
LSU Historical Dissertations and Theses
In many dicotyledons, the nutrient reserves are stored in the cotyledons. Phaseolin, 7S globulin, is the major seed protein from common bean Phaseolus vulgaris. In vitro transcription assays and gene transfer studies indicate that phaseolin gene expression is regulated primarily at the transcriptional level. In this dissertation, I studied cis- and trans-acting factors that may play a role in the transcriptional regulation of the $\beta$-phaseolin gene. Gel mobility shift and exonuclease III protection assays identified four distinct DNA binding proteins, CAN, AG-1, CA-1, and TATA-box binding protein. Three CANNTG motifs, CACGTG ($-$248/$-$243), CACCTG ($-$163/$-$158), and CATATG ($-$100/$-$95), were found to …
The Effect Of Carbon Dioxide Concentration On Carbonic Anhydrase And Other Proteins In Chlamydomonas Reinhardtii., Mamta Rawat
The Effect Of Carbon Dioxide Concentration On Carbonic Anhydrase And Other Proteins In Chlamydomonas Reinhardtii., Mamta Rawat
LSU Historical Dissertations and Theses
Unicellular green algae, like Chlamydomonas reinhardtii, are able to grow photoautotrophically at low levels of CO$\sb2$. The efficient growth at low CO$\sb2$ levels is a reflection of the CO$\sb2$ concentrating mechanism that is induced when cells are adapted to low CO$\sb2$ levels. In this dissertation, the effect of CO$\sb2$ on carbonic anhydrase and other proteins in C. reinhardtii is discussed. In the first part of the dissertation, the isolation and purification of a new isoenzyme of carbonic anhydrase is reported. This carbonic anhydrase is present when cells are grown in high CO$\sb2$ but absent in low CO$\sb2$. It is located …