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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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Utility Of Remote Sensing Technology In Wetland Soil And Gas Flux Studies., Ramona Eva Pelletier Travis Jan 1994

Utility Of Remote Sensing Technology In Wetland Soil And Gas Flux Studies., Ramona Eva Pelletier Travis

LSU Historical Dissertations and Theses

Much of the traditionally used remotely sensed data is surface-oriented, which places some limits on its utility in wetland soil studies. In wetland environments the sediment surface is often obscured by vegetation and/or by water making the soil difficult to view. This study examines the possible utility of remotely sensed data from selected regions of the EM spectrum for wetland soil and gas flux studies. The visible, near-infrared, mid-infrared, thermal, and microwave regions (all mostly surface-oriented); and the ground penetrating radar (VLF) and inductive EM (ULF) regions (mostly subsurface-oriented) were investigated and example wetland soil applications demonstrated. Study sites ranged …

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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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Intraspecific Variation In The Response Of Baldcypress (Taxodium Distichum) Seedlings To Salinity., James Andrew Allen Jan 1994

Intraspecific Variation In The Response Of Baldcypress (Taxodium Distichum) Seedlings To Salinity., James Andrew Allen

LSU Historical Dissertations and Theses

This study evaluated genotypic variation in responses of baldcypress (Taxodium distichum) seedlings to combined flooding and salinity stress. Two experiments form the core of this dissertation. In the first experiment, seedlings of 15 open-pollinated families of baldcypress were exposed to combined salinity and flooding stress under greenhouse conditions. Ten of the families were from coastal locations that were slightly brackish. The other families were from freshwater locations. Five salinity levels were investigated--0, 2, 4, 6, and 8 g l$\sp{-1}$ artificial seawater--all with shallow flooding. Substantial variation was found among salinity levels and families for most of the response variables assessed. …

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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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Continuous Variation In Ellen Taaffe Zwilich's "Intrada", And "Generations", An Original Composition For Soprano, Tenor, And Orchestra., George Albert Benner Jan 1994

Continuous Variation In Ellen Taaffe Zwilich's "Intrada", And "Generations", An Original Composition For Soprano, Tenor, And Orchestra., George Albert Benner

LSU Historical Dissertations and Theses

This dissertation divides into two parts. The first part illustrates certain traits of Ellen Taaffe Zwilich's neo-Romantic style by analyzing a single piece, Intrada (1983) for five players. The analysis is in three main sections. The first section discusses how Zwilich's background might have influenced her post-1979 writing, particularly her interest in continuous variation through the writings of Schoenberg and her studies with Sessions, and Carter. The second section focuses on Intrada and Zwilich's use of continuous variation. This section also analyzes cyclical elements and considers various older principles of melodic and pitch recurrence while determining the form of this …

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Traction And Agricultural Tractor Tire Selection Studies., Francois Pascal Brassart Jan 1994

Traction And Agricultural Tractor Tire Selection Studies., Francois Pascal Brassart

LSU Historical Dissertations and Theses

A machine was built to study non-rolling tire stiffness and damping coefficients of agricultural tractor tires in the vertical direction. Static deflection on a rigid surface was measured as a function of vertical load. During dynamic experiments, a sinusoidal forcing function was imposed on the test tire to determine dynamic stiffness and damping coefficient from load and deflection measurements. The experimental setup and methodology are described. Ten tires were tested. Both static and dynamic stiffnesses appeared linearly related to inflation pressure. No correlation was found between dynamic properties and excitation frequency. Comparisons among stiffness and damping coefficient values were made …

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The Structural Basis For Kinetic And Allosteric Differences Between Two Bacterial Phosphofructokinases., Walton Malcolm Byrnes Jan 1994

The Structural Basis For Kinetic And Allosteric Differences Between Two Bacterial Phosphofructokinases., Walton Malcolm Byrnes

LSU Historical Dissertations and Theses

The fructose 6-phosphate (Fru-6P) saturation curve for phosphofructokinase (PFK) from E. coli is sigmoidal in the presence of saturating MgATP levels, while the corresponding curve for B. stearothermophilus PFK is essentially hyperbolic. Sigmoidality can be due to apparent cooperativity arising from the kinetic mechanism of an enzyme. We have determined the kinetic mechanism of B. stearothermophilus PFK (BsPFK). BsPFK was found to obey a non rapid-equilibrium random mechanism similar to the one E. coli PFK (EcPFK) follows. Substrate inhibition by MgATP was observed. We propose that substrates bind to BsPFK through two alternative pathways, one of which is slower. The …

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A Relaxation Scheme For Mesh Locality In Computer Vision., Weian Deng Jan 1994

A Relaxation Scheme For Mesh Locality In Computer Vision., Weian Deng

LSU Historical Dissertations and Theses

Parallel processing has been considered as the key to build computer systems of the future and has become a mainstream subject in Computer Science. Computer Vision applications are computationally intensive that require parallel approaches to exploit the intrinsic parallelism. This research addresses this problem for low-level and intermediate-level vision problems. The contributions of this dissertation are a unified scheme based on probabilistic relaxation labeling that captures localities of image data and the ability of using this scheme to develop efficient parallel algorithms for Computer Vision problems. We begin with investigating the problem of skeletonization. The technique of pattern match that …

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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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Structural Equation Modeling Analysis Of Risk Factors For The Development Of Eating Disorder Symptoms In Adolescents., Susan Elizabeth Barker Jan 1994

Structural Equation Modeling Analysis Of Risk Factors For The Development Of Eating Disorder Symptoms In Adolescents., Susan Elizabeth Barker

LSU Historical Dissertations and Theses

Risk factors which have been shown to influence the development of body dissatisfaction and eating disturbance in adolescents include depressed mood, low self-esteem, a history of teasing about physical appearance, social and parental pressure to be thin, pubertal timing, and actual body weight or body mass index. In the present study, an etiological model was proposed with these risk factors as predictors of the presence of eating disorder symptoms; this association was hypothesized to be mediated by dissatisfaction with body shape and weight. Structural equation modeling was used to test this theoretical model within a total sample of 345 adolescent …

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Cauldron Of Changes: Feminist Spirituality In Contemporary American Women's Fiction., Janice Celia Crosby Jan 1994

Cauldron Of Changes: Feminist Spirituality In Contemporary American Women's Fiction., Janice Celia Crosby

LSU Historical Dissertations and Theses

My dissertation, Cauldron of Changes: Feminist Spirituality in Contemporary American Women's Fiction, combines feminist perspectives from literary and religious thinkers to inform a discussion of the overlooked aspects of contemporary European-American women's speculative fiction. The introductory chapter provides an overview of the feminist spirituality movement as it incorporates Goddess- and earth-centered religious perspectives, and covers the themes common to both spiritual practice and fiction. "Rewriting History and Legend," the second chapter, shows how the feminist spirituality movement has furthered the feminist project of rewriting myth, legend, and history, thus challenging the foundations of the cultural tradition of the West. In …

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Arabidopsis Glabrous1 Gene Requires Downstream Sequences For Function, J. C. Larkin, D. G. Oppenheimer, S. Pollock, M. D. Marks Dec 1993

Arabidopsis Glabrous1 Gene Requires Downstream Sequences For Function, J. C. Larkin, D. G. Oppenheimer, S. Pollock, M. D. Marks

Faculty Publications

No abstract provided.

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Louisiana Agriculture Magazine, Fall 1993, Lsu Agricultural Experiment Station Oct 1993

Louisiana Agriculture Magazine, Fall 1993, Lsu Agricultural Experiment Station

Louisiana Agriculture

No abstract provided.

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Structure Of The Epididymal Retinoic Acid Binding Protein At 2.1 Å Resolution, Marcia E. Newcomer Sep 1993

Structure Of The Epididymal Retinoic Acid Binding Protein At 2.1 Å Resolution, Marcia E. Newcomer

Faculty Publications

Background: Androgen-dependent proteins in the lumen of the epididymis are required for sperm maturation. One of these is a retinoic acid binding protein, E-RABP, which binds both all-trans and 9-cis retinoic acid. The other retinoid-binding proteins whose structures are known do not bind 9-cis retinoids. Results: We describe the X-ray structure determination of E-RABP with and without bound ligand. The ligand binds deep in the β-barrel of the protein, the β-ionone ring innermost. The binding site, like the ligand, is amphipathic and the deepest part of the cavity is formed by a ring of aromatic amino acids. The isoprene tail …

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An Economic Analysis Of Waterfowl Hunting In Louisiana (Bulletin #841), Christopher Ec Gan, E. Jane Luzar Jul 1993

An Economic Analysis Of Waterfowl Hunting In Louisiana (Bulletin #841), Christopher Ec Gan, E. Jane Luzar

LSU AgCenter Bulletins

Waterfowl-related activities generate millions of dollars for Louisiana’s economy annually, with duck and goose hunting as one of the most significant sporting activities. Economic information on the characteristics that influence the decision to hunt waterfowl can provide valuable information to resource managers faced with declining waterfowl populations as well as declining numbers of waterfowl hunters.

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Mammalogical Type Specimens In The Museum Of Natural Science, Louisiana State University, Mark S. Hafner Mar 1993

Mammalogical Type Specimens In The Museum Of Natural Science, Louisiana State University, Mark S. Hafner

Occasional Papers of the Museum of Natural Science, Louisiana State University

No abstract provided.

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Herpetological Type Specimens In The Museum Of Natural Science, Louisiana State University, Douglas A. Rossman, David A. Good Mar 1993

Herpetological Type Specimens In The Museum Of Natural Science, Louisiana State University, Douglas A. Rossman, David A. Good

Occasional Papers of the Museum of Natural Science, Louisiana State University

No abstract provided.

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Endogenous Retinoids In Rat Epididymal Tissue And Rat And Human Spermatozoa, R. S. Pappas, M. E. Newcomer, D. E. Ong Jan 1993

Endogenous Retinoids In Rat Epididymal Tissue And Rat And Human Spermatozoa, R. S. Pappas, M. E. Newcomer, D. E. Ong

Faculty Publications

Recent work has demonstrated high levels of retinoid binding proteins in rat epididymis, and a lumenal retinoic acid binding protein has been purified. These findings suggested that vitamin A may be involved in spermatozoal maturation in the epididymis. We further addressed this question by quantifying retinol, retinyl esters, and retinoic acid isomers from perfused epididymal tissue, from rat testicular and epididymal spermatozoa, and from human ejaculate sperm. HPLC showed vitamin A levels to be higher in caput than in corpus or cauda tissue. Retinoic acid and 9-cis-retinoic acid were found to be graded from lowest levels in caput to highest …

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Carbon, Nitrogen, And Phosphorus Leaching Rates From Spartina Alterniflora Salt Marshes, R. Eugene Turner Jan 1993

Carbon, Nitrogen, And Phosphorus Leaching Rates From Spartina Alterniflora Salt Marshes, R. Eugene Turner

Faculty Publications

Annual carbon, nitrogen, and phosphorus leachate rates from live Spartina alterniflora Loisel in a Louisiana (USA) salt marsh were estimated to be 200, 14, and 3 g m-2, respectively, and to peak in summer and higher salinit~es. Leachate losses of P, N and C are equivalent to a turnover of live plant tissues of 10, 17 and 49 d, respectively, when submerged, and 148, 250 and 721 d, respectively, when unsubmerged. Plant leachate losses during marsh submergence and non-submergence are nearly equal because release rates are 15x greater during submergence. Nitrogen and carbon concentrations relative to phosphorus are proportionately 4x …

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Carbon, Nitrogen, And Phosphorus Leaching Rates From Spartina-Alterniflora Salt Marshes, R E. Turner Jan 1993

Carbon, Nitrogen, And Phosphorus Leaching Rates From Spartina-Alterniflora Salt Marshes, R E. Turner

Faculty Publications

Annual carbon, nitrogen, and phosphorus leachate rates from live Spartina alterniflora Loisel in a Louisiana (USA) salt marsh were estimated to be 200, 14, and 3 g M-2, respectively, and to peak in summer and higher salinities. Leachate losses of P, N and C are equivalent to a turnover of live plant tissues of 10, 17 and 49 d, respectively, when submerged, and 148, 250 and 721 d, respectively, when unsubmerged. Plant leachate losses during marsh submergence and non-submergence are nearly equal because release rates are 15 x greater during submergence. Nitrogen and carbon concentrations relative to phosphorus are proportionately …

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The Phylogeny Of The Prasinophyceae And Pleurastrophyceae (Chlorophyta) Inferred From Ribosomal Rna Genes And Morphology., Thomas Sinclair Kantz Jan 1993

The Phylogeny Of The Prasinophyceae And Pleurastrophyceae (Chlorophyta) Inferred From Ribosomal Rna Genes And Morphology., Thomas Sinclair Kantz

LSU Historical Dissertations and Theses

The phylogeny of the problematic green algal classes Prasinophyceae and Pleurastrophyceae (Chlorophyta) sensu Mattox and Stewart (1984) was inferred from ultrastructural and biochemical data, and from ribosomal RNA gene sequence data. Analysis of a data set of ultrastructural and biochemical characters (with a predominance of flagellar and cell covering features) revealed a monophyletic Pleurastrophyceae and a monophyletic Prasinophyceae. Rerooting experiments indicated that the ancestral flagellate was likely Pedinomonas-like or Mamiellales-like. The cladograms generated from the ribosomal RNA gene sequence data show that the Pleurastrophyceae is not monophyletic; however, pleurastrophycean taxa are more closely related to the Chlorophyceae than to any …

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The Significance Of Beta-72 Asparagine Methylation In C-Phycocyanin., Beth Ann Thomas Jan 1993

The Significance Of Beta-72 Asparagine Methylation In C-Phycocyanin., Beth Ann Thomas

LSU Historical Dissertations and Theses

A novel post-translationally modified asparagine, $\gamma$-N-methylasparagine (NMA), has been characterized at the $\beta$-72 site in many phycobiliproteins. The behavior of a NMA-containing peptide under Edman degradation conditions employed for sequence analysis was examined; NMA can be reproducibly identified in protein sequences by careful attention to repetitive yields and the presence of minor peaks. The effects of asparagine methylation on photosynthetic rates in the cyanobacterium Synechococcus PCC 7942 and two methylase-minus mutants was measured by steady-state oxygen evolution in whole cells. The methylase-minus mutants demonstrated lower rates of electron transfer through Photosystem II under conditions in which phycobilisomes were preferentially illuminated …

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Differential Susceptibility Of Guanine Nucleotide-Binding Proteins To Pertussis Toxin-Catalyzed Adp-Ribosylation In Brain Membranes Of Two Congeneric Marine Fishes, T. F. Murray, J. F. Siebenaller Jan 1993

Differential Susceptibility Of Guanine Nucleotide-Binding Proteins To Pertussis Toxin-Catalyzed Adp-Ribosylation In Brain Membranes Of Two Congeneric Marine Fishes, T. F. Murray, J. F. Siebenaller

Faculty Publications

No abstract provided.

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Synaptic Transmission Between Pairs Of Retinal Amacrine Cells In Culture, E. Gleason, S. Borges, M. Wilson Jan 1993

Synaptic Transmission Between Pairs Of Retinal Amacrine Cells In Culture, E. Gleason, S. Borges, M. Wilson

Faculty Publications

We have examined synaptic transmission between isolated pairs of chick GABAergic amacrine cells, maintained in sparse culture and identified by their binding of an amacrine cell-selective antibody. Using the perforated- patch method to whole-cell clamp both cells of a pair, postsynaptic currents were examined for step depolarizations of the 'presynaptic' cell. Synaptic transmission, frequently reciprocal, was calcium dependent and reversibly blocked by bicuculline. Postsynaptic currents, excluding those due to ohmic electrical coupling, were elicited only for presynaptic voltage steps positive to about -40 mV and were always very noisy, suggesting that they were summed from relatively small numbers of quanta. …

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Design Of A Functional Calcium Channel Protein: Inferences About An Ion Channel‐Forming Motif Derived From The Primary Structure Of Voltage‐Gated Calcium Channels, Anne Grove, John M. Tomich, Takeo Iwamoto, Mauricio Montal Jan 1993

Design Of A Functional Calcium Channel Protein: Inferences About An Ion Channel‐Forming Motif Derived From The Primary Structure Of Voltage‐Gated Calcium Channels, Anne Grove, John M. Tomich, Takeo Iwamoto, Mauricio Montal

Faculty Publications

To identify sequence‐specific motifs associated with the formation of an ionic pore, we systematically evaluated the channel‐forming activity of synthetic peptides with sequence of predicted transmembrane segments of the voltage‐gated calcium channel. The amino acid sequence of voltage‐gated, dihydropyridine (DHP)‐sensitive calcium channels suggests the presence in each of four homologous repeats (I–IV) of six segments (S1–S6) predicted to form membrane‐spanning, α‐helical structures. Only peptides representing amphipathic segments S2 or S3 form channels in lipid bilayers. To generate a functional calcium channel based on a four‐helix bundle motif, four‐helix bundle proteins representing IVS2 (T4CaIVS2) or IVS3 (T4CaIVS3) were synthesized. Both proteins …

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Glucose Uptake And End Product Formation In An Intertidal Marine Sediment, T. E. Sawyer, G. M. King Jan 1993

Glucose Uptake And End Product Formation In An Intertidal Marine Sediment, T. E. Sawyer, G. M. King

Faculty Publications

Glucose uptake was monitored on a seasonal basis, using [6-3H]glucose and undisturbed cores collected from an intertidal mud flat. The fate of glucose carbon, including the formation of CO2 and biomass, was assayed by using undisturbed cores and [U-14C]glucose; the production of short-chain fatty acids was monitored with [U-14C]glucose and sediment slurries. Rate constants for glucose uptake varied temporally, with temperature accounting for much of the variability; turnover times ranged from about 2 to 10 min. Rate constants decreased with increasing sediment depth and in the following order for several common monosaccharides: glucose>galactose>mannose~fucose. Time course analyses of 14CO2 …

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Methane Consumption In Temperate And Subarctic Forest Soils: Rates, Vertical Zonation, And Responses To Water And Nitrogen, A. P.S. Adamsen, G. M. King Jan 1993

Methane Consumption In Temperate And Subarctic Forest Soils: Rates, Vertical Zonation, And Responses To Water And Nitrogen, A. P.S. Adamsen, G. M. King

Faculty Publications

Rates of methane consumption were measured in subarctic coniferous and temperate mixed-hardwood forest soils, using static chambers and intact soil cores. Rates at both sites were generally between 1 and 3 mg of CH4 m-2 day-1 and decreased with increasing soil water contents above 20%. Addition of ammonium (1 μmol g of soil-1) strongly inhibited methane oxidation in the subarctic soils; a lesser inhibition was observed for temperate forest samples. The response to nitrogen additions occurred within a few hours and was probably due to physiological changes in the active methane-consuming populations. Methane consumption in soils from both sites was …

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