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Life History Biology And Soil Characteristics Of Two Species Of Arctomecon (Papaveraceae), Shelia Kathleen Sheldon Jan 1994

Life History Biology And Soil Characteristics Of Two Species Of Arctomecon (Papaveraceae), Shelia Kathleen Sheldon

UNLV Retrospective Theses & Dissertations

Two rare plant species of the Mojave Desert were investigated in this study. Life history and reproductive data as well as vegetative associates and soil characteristics for Arctomecon californica Torr. and Frem. and Arctomecon merriamii Cov. were collected. Results for the life history and reproductive data show that the highest mortality in both species occurs at the seedling stage. Loss of potential seed, for both species, was highest at the bud and capsule stage. Arctomecon californica was found to be reproductively self-incompatible, while A. merriamii was able to self-pollinate. Results from the vegetative and soil data show that the vegetation …

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Role Of Curved Dna In Promoter Recognition With Bacillus Subtilis And Escherichia Coli Rna Polymerase., Cheryl Anne Nickerson Jan 1994

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 …

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Permethrin Resistance In The Soybean Looper, Pseudoplusia Includens (Walker): Geographic Variation, Mechanisms, Inheritance, And Host Plant Effects., James Donald Thomas Jr Jan 1994

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 …

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Host Plant Adaptation In The Two Strains Of Fall Armyworm (Lepidoptera: Noctuidae)., Klaas H. Veenstra Jan 1994

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, …

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Factors Affecting Sediment Transport, Deposition And Erosion In Intertidal Wetlands In Louisiana., Roelof Maria Boumans Jan 1994

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 …

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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 Jan 1994

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 …

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Demographic And Genetic Studies Of Seed Dispersal And Juvenile Survival In An Old-Growth Longleaf Pine Population., Susan Langevin Grace Jan 1994

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 …

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Seasonal And Spatial Abundance And Size Distribution Of Fishes Associated With A Petroleum Platform In The Northern Gulf Of Mexico., David Robert Stanley Jan 1994

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 …

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Life History Responses To Fire Season In A Clonal Herb, Pityopsis Graminifolia (Asteraceae)., John Stephen Brewer Jan 1994

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. …

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Investigations On Insecticide Resistance In Tobacco Budworm, Heliothis Virescens (F.), And Boll Weevil, Anthonomus Grandis Grandis Boheman, In The Mid-South., Scott Hamilton Martin Jan 1994

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 …

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Latitudinal Gradients In Temperate And Tropical Seasonal Forests., Martin Francis Quigley Jan 1994

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 …

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The Production And Characterization Of Alginate Produced By Pseudomonas Syringae., Richard David Ashby Jan 1994

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 …

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Sedimentation Processes In Selected Coastal Wetlands From The Gulf Of Mexico And Northern Europe., John Charles Callaway Jan 1994

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 …

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Immunological And Developmental Factors Affecting The Efficacy Of In Vitro Fertilization, Embryo Culture And Embryo Transfer In The Domestic Cat., William Frederick Swanson Jan 1994

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.

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Epidemiology Of Strongylate Nematode And Coccidia (Eimeria) Infection In Sheep With Special Reference To Breed Resistance., Mahesan Bahirathan Jan 1994

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, …

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Effects Of Nandrolone Decanoate On Strength, Markers Of Bone Formation And Turnover In Obese Postmenopausal Women With Normal Bone Density., Ellen Rose Brooks Jan 1994

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 …

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Evolutionary Patterns In Proteaceae Based On Comparative Floral And Inflorescence Ontogenies., Andrew William Douglas Jan 1994

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. …

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The Effect Of Carbon Dioxide Concentration On Carbonic Anhydrase And Other Proteins In Chlamydomonas Reinhardtii., Mamta Rawat Jan 1994

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 …

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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 Jan 1994

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 …

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The Mode Of Action Of Intersex In Terminal Sexual Differentiation In Drosophila., Robert Russel Risley Dec 1993

The Mode Of Action Of Intersex In Terminal Sexual Differentiation In Drosophila., Robert Russel Risley

Student Work

The intersex gene (2-60.5) lies at the terminus of the regulatory pathway that determines sex-type in Drosophila. Its product functions with the female-specific product of doublesex, another gene in the self-determination regulatory pathway, to regulate female-specific differentiation. However, the mechanism of this regulation has not been clearly demonstrated. Using a temperature-sensitive allele at intersex to eliminate its function at time points both during development and in the adult stage, the mode by which intersex regulates female determination was addressed. When chromosomal females bearing a temperature-sensitive intersex allele are raised at a permissive temperature, they develop as phenotypic females. Animals raised …

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Plant Species Distribution Along Topographic Gradients In Tallgrass Prairies Of Eastern Nebraska., Ghanim A. S. Abbadi May 1993

Plant Species Distribution Along Topographic Gradients In Tallgrass Prairies Of Eastern Nebraska., Ghanim A. S. Abbadi

Student Work

Plant species composition was evaluated along a slope gradient in two native tallgrass prairies of eastern Nebraska. Forb cover differed significantly (P<0.05) along the topographic gradient at both sites, however, grass covered differed only at one site (P<0.05). A site-by-site comparison by topographic location indicates significant differences between lower slopes for grass and between upper slopes for forbs. Big bluestem (Andropogon gerardii Vitman) dominated all topographic locations at both sites (average cover = 64%) with no significant differences in the topographic distribution. Kentucky bluegrass (Poa pratensis L.), little bluestem (Andropogon scoparius Michx.), false boneset Kuhnia eupatorioides L.) prairie wild rose (Rosa arkansana Porter), prairie violet (Viola pedatifida G. Don), and sedge (Carex L. spp.) also show the no significant topographic preference at either site. Mid-slope locations contained the greatest number of species that differed significantly along the topographic gradient. Leadplant (Amorpha canescens Pursh) and indiangrass (Sorghastrum nutans (L.) Nash) were the two most common species showing high canopy cover values in mid-slope locations at both sites. Significant topographic distributions were also noted for scoring rush (Equisetum lawvigatum A. Br.) at both sites and for finger coreopsis (Coreopsis palmata Nutt.) found only at one site. Flowering spurge (Euphobia corollate L.) and sideoats grama (Bouteloua curtipendula (Michx.) Torr.) were significantly higher on the hilltop locations of one site.

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Identification And Characterization Of Tdd-1 And Related Retrotransposons In Dictyostelium., Gail A. Henderson May 1993

Identification And Characterization Of Tdd-1 And Related Retrotransposons In Dictyostelium., Gail A. Henderson

Student Work

Previous studies in Dictyostelium discoideum on the transposable element Tdd-1, have identified two transcription units of opposite polarity. One is a major, developmentally regulated 4.5 kb transcript believed to encode proteins involved in the retrotransposition of this element, and the other, 1.4 kb in size, is a heat-shock inducible RNA. Based on the sequence of the 4.5 kb transcript and the encoded amino acid sequence, it has been proposed that Tdd-1 is a retrotransposon. This implies that the 4.5 kb mRNA is copied by reverse transcriptase, resulting in DNA copies that insert into new sites. The purpose of this study …

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Designating Male Parents At Birth, Jeffrey A. Parness May 1993

Designating Male Parents At Birth, Jeffrey A. Parness

University of Michigan Journal of Law Reform

In focusing on legal designations of male parentage as of the time of birth, this Essay first reviews the methods by which such designations currently are made. The difficulties raised by contemporary methods then will be explored, together with suggested reforms involving laws that could promote earlier, more complete, and more accurate designations of male parentage as of the time of a child's birth.

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Decomposition Of Senescent Blades Of The Seagrass Halodule Wrightii In A Subtropical Lagoon, Stephen Opsahl, Ronald Benner Apr 1993

Decomposition Of Senescent Blades Of The Seagrass Halodule Wrightii In A Subtropical Lagoon, Stephen Opsahl, Ronald Benner

Faculty Publications

Senescent blades from the seagrass Halodule wrightii Aschers were suspended in the water column of Laguna Madre (Texas, USA) for a period of 419 d, representing the longest seagrass decomposition study to date. The initial stage of decomposition was characterized by a rapid loss of organic matter (36 % in 24 d) attributed to leaching. A total of 76 % of the organic matter from seagrass tissues was lost by the end of the decomposition period. Of the major bulk constituents measured, neutral sugars were most abundant and accounted for 23 % of the ash-free dry wt of the initial …

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Hepatic Lipase Treatment Of Chylomicron Remnants Increases Exposure Of Apolipoprotein E, Dawn L. Brasaemle, Kathleen Cornely-Moss, André Bensadoun Mar 1993

Hepatic Lipase Treatment Of Chylomicron Remnants Increases Exposure Of Apolipoprotein E, Dawn L. Brasaemle, Kathleen Cornely-Moss, André Bensadoun

Chemistry & Biochemistry Faculty Publications

The consequences of hepatic lipase treatment of chylomicron remnants were studied. Rats were fed corn oil to induce production and secretion of chylomicrons and were then injected with polyclonal antiserum raised against hepatic lipase to specifically and quantitatively inhibit hepatic lipase activity in vivo. A fraction enriched in chylomicron remnants was isolated from rat plasma by a brief centrifugation step that preferentially isolates triglyceride-rich apolipoprotein (apo) B-48-containing lipoproteins. The chylomicron remnants were then treated with hepatic lipase in vitro, or incubated under identical conditions in the absence of enzyme (control incubations). Hepatic lipase-treated and control chylomicron remnants were isolated by …

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Bioremediation: A New Technology Using Inhabitants Of The Soil, Matthew Fields Jan 1993

Bioremediation: A New Technology Using Inhabitants Of The Soil, Matthew Fields

Mahurin Honors College Capstone Experience/Thesis Projects

Bioremediation is the use of microorganisms to clean the environment contaminated with various pollutants such as chemical wastes and petroleum -based products. The microbes use the pollutants as their carbon source and by doing so the contaminants are broken down. This paper examined the numbers of indigenous microorganisms in soil contaminated with diesel fuel and oil. Contaminant-degrading microbes were isolated and enumerated using phenanthrene in mineral media. The breakdown of phenanthrene was used as an indicator for contaminant degradation. The effects of aeration and the addition of nutrients on bioremediation processes was also studied. Soil samples used in the performed …

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A Role For Metallothionein In Human Monocytes, Martha E. Leibbrandt Jan 1993

A Role For Metallothionein In Human Monocytes, Martha E. Leibbrandt

Digitized Theses

The metal-binding protein metallothionein (MT) confers resistance to the toxic effects of metals. A role in metal homeostasis and protection against toxic free radicals has been suggested, but no physiological function has been established. The ability of human monocytes to be activated by lipopolysaccharide (LPS) provided a model to investigate the effect of zinc on both cellular activation ({dollar}\rm H\sb2O\sb2{dollar} production, indicating the respiratory burst) and MT expression. In freshly-isolated primary human monocytes and a human monocytic cell line (THP-1), LPS induced activation and MT expression: LPS did not induce MT expression in human melanoma cells. Co-treatment of THP-1 cells …

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Neurotransmitter Interactions In The Substantia Nigra And In The Neostriatum Following Nigral Grafts, Ivar Marcelo Mendez Jan 1993

Neurotransmitter Interactions In The Substantia Nigra And In The Neostriatum Following Nigral Grafts, Ivar Marcelo Mendez

Digitized Theses

Direct synaptic contact between substance P (SP)-immunoreactive terminals and glutamic acid decarboxylase (GAD)-positive neurons was more often observed in the substantia nigra pars lateralis (SNL) than in the substantia nigra pars reticulata (SNR) and was rarely observed in the substantia nigra pars compacta (SNC). Substance P terminals also formed synapses with cell bodies and dendrites of tyrosine hydroxylase (TH)-positive, dopaminergic neurons in the SNC and SNR. Multiple SP terminals were often observed with symmetrical and, less frequently, asymmetrical synapses on individual TH-containing dendrites. Evidence of SP-containing terminals contacting both GABAergic and dopaminergic neurons in the substantia nigra suggests a direct …

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Control Of Tonic Sympathetic Nerve Activity By The Brainstem In Rats, Kristen Hayes Jan 1993

Control Of Tonic Sympathetic Nerve Activity By The Brainstem In Rats, Kristen Hayes

Digitized Theses

Control of tonic firing of sympathetic nerves by the rostral ventrolateral medulla (RVLM) and the pontine reticular formation (PRF) was investigated. Electrical activity of renal, splenic, mesenteric and preganglionic greater splanchnic nerves and T{dollar}\sb{lcub}13{rcub}{dollar} white rami was recorded in artificially respired, urethane-anaesthetized rats. Glycine (1.0M;180nl) was microinjected into the RVLM to inhibit neuronal discharge and effects on these nerves were compared. To study descending inhibitory influences on these nerves, effects of RVLM blockade were compared to effects of cervical spinal cord transection. RVLM blockade caused greater decreases in discharge of renal ({dollar}-44\ \pm\ 3\%{dollar}) than splenic ({dollar}-31\ \pm\ 2\%{dollar}) nerves, …

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Cyclic Adenosine 3',5'-Monophosphate And Prostaglandin E(2) During Decidualization In The Rat, Gayle M. Yee Jan 1993

Cyclic Adenosine 3',5'-Monophosphate And Prostaglandin E(2) During Decidualization In The Rat, Gayle M. Yee

Digitized Theses

Prostaglandin E{dollar}\sb2{dollar} (PGE{dollar}\sb2{dollar}) is an important mediator of implantation and decidualization during pregnancy. However, its mechanism of action in the uterus is unclear. Endometrial alkaline phosphatase (ALP) activity increases during decidualization in many species and provides a marker for assessment of cellular aspects of decidualization. The objective of this study was to examine the relationship between PGE{dollar}\sb2{dollar} and cyclic adenosine 3{dollar}\sp\prime{dollar},5{dollar}\sp\prime{dollar}-monophosphate (cAMP) during decidualization in the rat. In ovariectomized rats treated with estrogen and progesterone to sensitize the uteri for decidualization, intrauterine infusion of indomethacin, an inhibitor of endogenous PG synthesis, inhibited the increase in endometrial ALP activity, which occurred …

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