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A Novel Α-Type Carbonic Anhydrase Associated With The Thylakoid Membrane In Chlamydomonas Reinhardtii Is Required For Growth At Ambient Co2, Jan Karlsson, Adrian K. Ciarke, Zhi Yuan Chen, Stephanie Y. Hugghins, Youn Il Park, H. David Husic, James V. Moroney, Göran Samuelsson Mar 1998

A Novel Α-Type Carbonic Anhydrase Associated With The Thylakoid Membrane In Chlamydomonas Reinhardtii Is Required For Growth At Ambient Co2, Jan Karlsson, Adrian K. Ciarke, Zhi Yuan Chen, Stephanie Y. Hugghins, Youn Il Park, H. David Husic, James V. Moroney, Göran Samuelsson

Faculty Publications

A 29.5 kDa intracellular α-type carbonic anhydrase, designated Cah3, from the unicellular green alga Chlamydomonas reinhardtii is the first of this type discovered inside a photosynthetic eukaryote cell. We describe the cloning of a cDNA which encodes the protein. Immunoblot studies with specific antibodies raised against Cah3 demonstrate that the polypeptide is associated exclusively with the thylakoid membrane. The putative transit peptide suggests that Cah3 is directed to the thylakoid lumen, which is confirmed further by the presence of mature sized Cah3 after thermolysin treatment of intact thylakoids. Complementation of the high inorganic carbon concentration-requiring mutant, cia3, with a subcloned …

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Hypertension Treatment And Control In Sub-Saharan Africa: The Epidemiological Basis For Policy, Richard S. Cooper, Charles N. Rotimi, Jay S. Kauftnan, Walinjom F.T. Muna, George A. Mensah Feb 1998

Hypertension Treatment And Control In Sub-Saharan Africa: The Epidemiological Basis For Policy, Richard S. Cooper, Charles N. Rotimi, Jay S. Kauftnan, Walinjom F.T. Muna, George A. Mensah

Faculty Publications

No abstract provided.

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Genetic Traces Of Ancient Demography, Henry C. Harpending, Marka Batzer, Michael Gurven, Lynn B. Jorde, Alan R. Rogers, Stephen T. Sherry Feb 1998

Genetic Traces Of Ancient Demography, Henry C. Harpending, Marka Batzer, Michael Gurven, Lynn B. Jorde, Alan R. Rogers, Stephen T. Sherry

Faculty Publications

Patterns of gene differences among humans contain information about the demographic history of our species. Haploid loci like mitochondrial DNA and the nonrecombining part of the Y chromosome show a pattern indicating expansion from a population of only several thousand during the late middle or early upper Pleistocene. Nuclear short tandem repeat loci also show evidence of this expansion. Both mitochondrial DNA and the Y chromosome coalesce within the last several hundred thousand years, and they cannot provide information about the population before their coalescence. Several nuclear loci are informative about our ancestral population size during nearly the whole Pleistocene. …

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Density Functional Study Of Spin State In Cpm(No)X2 (M = Mo, Cr; X = Cl, Nh2, Ch3): Spectrochemical And Nephelauxetic Effects In Organometallic Compounds, Peter Legzdins, W. Stephen Mcneil, Kevin M. Smith, Rinaldo Poli Feb 1998

Density Functional Study Of Spin State In Cpm(No)X2 (M = Mo, Cr; X = Cl, Nh2, Ch3): Spectrochemical And Nephelauxetic Effects In Organometallic Compounds, Peter Legzdins, W. Stephen Mcneil, Kevin M. Smith, Rinaldo Poli

Faculty Publications

The relationship between spin state and metal-ligand bonding interactions in CpM(NO)-X2 species was investigated using density functional computational techniques. The geometries of CpM(NO)Cl2 (M = Cr, Mo), CpCr(NO)(NH2)X, and CpCr(NO)(CH3)X (X = Cl, CH3) were optimized at the DFT-B3LYP level for both the diamagnetic (S = 0) and paramagnetic (S = 1) electronic configurations. While the geometric parameters of the singlet compounds matched well with structures determined experimentally, the Cr-NO bond lengths in the triplet species exceeded the experimentally observed range by a significant margin, thereby indicating a propensity for nitrosyl-ligand dissociation from the high-spin complexes. The order of relative …

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Fluctuating Silicate : Nitrate Ratios And Coastal Plankton Food Webs, N Qureshi, N N. Rabalais, Q Dortch, R. Eugene Turner, R F. Shaw, J Cope Jan 1998

Fluctuating Silicate : Nitrate Ratios And Coastal Plankton Food Webs, N Qureshi, N N. Rabalais, Q Dortch, R. Eugene Turner, R F. Shaw, J Cope

Faculty Publications

Marine diatoms require dissolved silicate to form an external shell. and their growth becomes Si-limited when the atomic ratio of silicate to dissolved inorganic nitrogen (SI:DIN) approaches 1:1, also known as the Redfield ratio. Fundamental changes in the diatom-to-zooplankton-to-higher trophic level food web should occur when this ratio falls below 1:1. and the proportion of diatoms in the phytoplankton community is reduced. We quantitatively substantiate these predictions by using a variety of data from the Mississippi River continental shelf, a system in which the SI:DIN loading ratio has declined from around 3:1 to 1:1 during this century because of land-use …

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Measurement And Inheritance Of Resistance To Sheath Blight Caused By Rhizoctonia Solani Kuhn In Rice., Xueyan Sha Jan 1998

Measurement And Inheritance Of Resistance To Sheath Blight Caused By Rhizoctonia Solani Kuhn In Rice., Xueyan Sha

LSU Historical Dissertations and Theses

Sheath blight (ShB), caused by Rhizoctonia solani Kuhn, has been the most destructive rice disease in Louisiana. To breed ShB resistant varieties, an effective procedure for screening progenies of segregating populations is required and detailed knowledge of the mode-of-inheritance of partial ShB resistance is also necessary. In this study four inoculation methods; rice hull/grain mixture (MIX), rice straw, toothpick, and brown rice, along with five assessment systems; 0-9 rating scale (RAT9), relative lesion height (RLH), disease severity (DS), disease incidence, and lesion height were compared on nine rice genotypes showing different resistance levels to ShB. Progenies of segregating populations from …

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The Effects Of An Enriched Environment On The Stereotypic Movement Of Individuals With Profound Mental Retardation., Brandi Braud Smiroldo Jan 1998

The Effects Of An Enriched Environment On The Stereotypic Movement Of Individuals With Profound Mental Retardation., Brandi Braud Smiroldo

LSU Historical Dissertations and Theses

The present study was an attempt to investigate the effects of a specific type of enriched environment on the stereotypic movements of individuals with severe and profound mental retardation. A multisensory room which contained visual, auditory, and tactile stimulation was used. Effects of brief exposure to the multisensory room was compared to effects of exposure to a placebo probe involving attention and access to tangibles and to no treatment controls. Comparisons were made during a 10-minute post-test session immediately following. No significant differences between groups on rate of stereotypic movements at post-test was noted, anecdotal information and review of raw …

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Development Of An Integrated Algal/Seed Clam Unit Using Recirculation, Computer-Control, And Fluidization Technologies., Timothy John Pfeiffer Jan 1998

Development Of An Integrated Algal/Seed Clam Unit Using Recirculation, Computer-Control, And Fluidization Technologies., Timothy John Pfeiffer

LSU Historical Dissertations and Theses

Computer-control, recirculation, and fluidized-bed technologies were utilized in the integration of a land-based seed clam nursery system with an algae production system to improve northern quahog seed production (6-10 mm). The components of the integrated system included: a seawater treatment system; an algae production system; a seed clam nursery system; and a computer-control system. Treatment of the incoming seawater for the integrated system included filtration (20, 1, and 0.5 micron), chlorination, UV sterilization, and ozonation. During the summer months a chiller was used to maintain the treated seawater at approximately $\rm 20\sp\circ C.$ The diatom, Chaetoceros muelleri, was cultured in …

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Ecology And Loss Assessment Of Selected Homopteran Pests On Sugarcane: Interactions With The Fire Ant, Solenopsis Wagneri Santschi., Andrew Evans Woolwine Jan 1998

Ecology And Loss Assessment Of Selected Homopteran Pests On Sugarcane: Interactions With The Fire Ant, Solenopsis Wagneri Santschi., Andrew Evans Woolwine

LSU Historical Dissertations and Theses

Field studies in 1995, 1996, and 1997, using insecticides to alter population densities of yellow sugarcane aphid, Sipha flava (Forbes), West Indian canefly, Saccharosydne saccharivora (Westwood) and the pink sugarcane mealybug, Saccharicoccus sacchari (Cockerell), indicated that sugarcane infested by these insects did not suffer sugar quality loss (as measured by brix, polarity, sucrose, purity, and theoretical recoverable sugar (TRS)). There was no apparent indication that Homoptera stressed sugarcane (indicated by concentrations of free amino acids in extracted sugarcane juice). A very slight, but significant increase in the percent brix was observed in sugarcane juice extracted from stalks washed free of …

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The Tiger And The Pangolin: Cultural Ecology, Landscape Ecology, And Nature Conservation In China's Southeast Uplands., Christopher Reed Coggins Jan 1998

The Tiger And The Pangolin: Cultural Ecology, Landscape Ecology, And Nature Conservation In China's Southeast Uplands., Christopher Reed Coggins

LSU Historical Dissertations and Theses

The Wuyi-Daiyun Mountains, which form the core of China's Southeast Uplands Region, support a mosaic of subtropical forest, grassland, and cropland habitats, with some 1,620 species of plants and 326 species of terrestrial vertebrates. Forty-two animal species are officially protected, including the highly endangered South China tiger (Panthera tigris amoyensis). This study, based on one year of field research, examines relationships between village land use, landscape change, and wildlife management in the Meihuashan Nature Reserve of Southwest Fujian. It includes comparative studies of reserves in Longxishan and Wuyishan, further north, and Daiyunshan, to the east. Over 500 local gazetteer records …

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Analysis Of Resistance Gene-Mediated Defense Responses In Arabidopsis Thaliana Plants Carrying A Mutation In Cpr5, Jens Boch, Michelle L. Verbsky, Tara L. Robertson, John C. Larkin, Barbara N. Kunkel Jan 1998

Analysis Of Resistance Gene-Mediated Defense Responses In Arabidopsis Thaliana Plants Carrying A Mutation In Cpr5, Jens Boch, Michelle L. Verbsky, Tara L. Robertson, John C. Larkin, Barbara N. Kunkel

Faculty Publications

In resistant plants, pathogen attack often leads to rapid activation of defense responses that limit multiplication and spread of the pathogen. To investigate the signaling mechanisms underlying this process, we carried out a screen for mutants in the signaling pathway governing resistance in Arabidopsis thaliana to the bacterial pathogen Pseudomonas syringae. This involved screening for suppressor mutations that restored resistance to a susceptible line carrying a mutation in the RPS2 resistance gene. A mutant that conferred resistance by activating defense responses in the absence of pathogens was isolated. This mutant, which carries a mutation at the CPR5 locus and was …

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Characterization Of Root-Associated Methanotrophs From Three Freshwater Macrophytes: Pontederia Cordata, Sparganium Eurycarpum, And Sagittaria Latifolia?, A. Calhoun, G. M. King Jan 1998

Characterization Of Root-Associated Methanotrophs From Three Freshwater Macrophytes: Pontederia Cordata, Sparganium Eurycarpum, And Sagittaria Latifolia?, A. Calhoun, G. M. King

Faculty Publications

Root-associated methanotrophic bacteria were enriched from three common aquatic macrophytes: Pontederia cordata, Sparganium eurycarpum, and Sagittaria latifolia. At least seven distinct taxa belonging to groups I and II were identified and presumptively assigned to the genera Methylosinus, Methylocystis, Methylomonas, and Methylococcus. Four of these strains appeared to be novel on the basis of partial 16S ribosomal DNA sequence analysis. The root-methanotroph association did not appear to be highly specific, since multiple methanotrophs were isolated from each of the three plant species. Group II methanotrophs were isolated most frequently; though less common, group I isolates accounted for three of the seven …

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Diversity Within Streptomyces Ipomoeae Based On Inhibitory Interactions, Rep-Pcr, And Plasmid Profiles, C. A. Clark, C. Chen, N. Ward-Rainey, G. S. Pettis Jan 1998

Diversity Within Streptomyces Ipomoeae Based On Inhibitory Interactions, Rep-Pcr, And Plasmid Profiles, C. A. Clark, C. Chen, N. Ward-Rainey, G. S. Pettis

Faculty Publications

Streptomyces soil rot is a destructive disease of sweetpotato (Ipomoea batatas) that causes yield loss resulting from decay of the feeder root system and reduced quality due to the presence of necrotic lesions on the storage roots. It is managed by the use of resistant cultivars, but variability of the pathogen has not been previously assessed. This study compared 36 strains of the pathogen Streptomyces ipomoeae from different locations in the United States and Japan. The strains could be separated into three groups on the basis of their ability to inhibit the growth of one another in in vitro assays. …

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From Archive To Map To Pastoral Landscape: A Spatial Perspective On The Livestock Ecology Of Sixteenth-Century New Spain, Andrew Sluyter Jan 1998

From Archive To Map To Pastoral Landscape: A Spatial Perspective On The Livestock Ecology Of Sixteenth-Century New Spain, Andrew Sluyter

Faculty Publications

No abstract provided.

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An Investigation On The Influence Of Feline Flea Allergy On The Fecundity Of The Cat Flea, Beth J. Mcdonald, Carol S. Foil, Lane D. Foil Jan 1998

An Investigation On The Influence Of Feline Flea Allergy On The Fecundity Of The Cat Flea, Beth J. Mcdonald, Carol S. Foil, Lane D. Foil

Faculty Publications

Survival, egg production and egg viability of fleas allowed to feed on eight flea-allergic and six flea-naive cats were compared. Fifty fleas, in feeding cages or free roaming, were allowed to feed on the cats. Flea-allergic cats removed significantly more free-roaming fleas than did flea-naive cats. Female fleas produced fewer eggs on flea-allergic cats than on flea-naive cats regardless of feeding method. There was no significant difference in egg viability between the two groups. The data suggest that flea-allergic cats efficiently removed fleas by grooming and that they also produce unknown factor(s) that affect the fecundity of fleas.

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Isolation, Culture And Characterization Of A Primary Fibroblast Cell Line From Channel Catfish, Quiyang Zhang, Richard K. Cooper, William R. Wolters, Terrence R. Tiersch Jan 1998

Isolation, Culture And Characterization Of A Primary Fibroblast Cell Line From Channel Catfish, Quiyang Zhang, Richard K. Cooper, William R. Wolters, Terrence R. Tiersch

Faculty Publications

A primary cell line (designated as CCf) derived from caudal fin tissue of channel catfish, Ictalurus punctatus, was developed using explant techniques. The cell line grew fastest in media supplied with FBS and channel catfish serum. The duplication time of the cell line under optimal conditions was ~56 h at a plating density of 1.1 x 105 cells/ml. The cell line has been propagated continuously for 25 passages (1:4 dilution per passage), cryopreserved, and recovered successfully at different passages. The cultured cells had fibroblastic morphology, and synthesized fibronectin and Type I and III collagens in the cytoplasm. The cell line …

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Egg Parasitoids Of Homalodisca Coagulata (Homoptera: Cicadellidae), Serguei V. Triapitsyn, Russell F. Mizell, Janice L. Bossart, Christopher E. Carlton Jan 1998

Egg Parasitoids Of Homalodisca Coagulata (Homoptera: Cicadellidae), Serguei V. Triapitsyn, Russell F. Mizell, Janice L. Bossart, Christopher E. Carlton

Faculty Publications

A survey of egg parasitoids of the leafhopper Homalodisca coagulata was conducted in California, Florida and Louisiana. The mymarid wasp Gonatocerus ashmeadi was found to be the most common natural enemy in all locations sampled; G. fasciatus and the trichogrammatid Zagella sp. are recognized as potential biological control agents for introduction into southern California.

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Identification And Characterization Of A 14-Kilodalton Brucella Abortus Protein Reactive With Antibodies From Naturally And Experimentally Infected Hosts And T Lymphocytes From Experimentally Infected Balb/C Mice, R. L. Chirhart-Gilleland, M. E. Kovach, P. H. Elzer, S. R. Jennings, R. M. Roop Jan 1998

Identification And Characterization Of A 14-Kilodalton Brucella Abortus Protein Reactive With Antibodies From Naturally And Experimentally Infected Hosts And T Lymphocytes From Experimentally Infected Balb/C Mice, R. L. Chirhart-Gilleland, M. E. Kovach, P. H. Elzer, S. R. Jennings, R. M. Roop

Faculty Publications

A low-molecular-weight recombinant Brucella abortus protein reactive with antibodies from a variety of naturally and experimentally infected hosts and T lymphocytes from experimentally infected mice was identified and given the designation BA14K. The gene encoding BA14K was cloned and characterized, and the predicted amino acid sequence of this immunoreactive protein showed no significant homology with previously described proteins. Sequences homologous to the cloned fragment encoding BA14K were identified by Southern blot analysis of genomic DNAs from representatives of all of the currently recognized Brucella species. Studies employing BA14K should contribute to our efforts to better understand the antigenic specificity of …

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Hematite And Calcite Coatings On Fossil Vertebrates, B. A.O. Huiming, Paul L. Koch, Robert P. Hepple Jan 1998

Hematite And Calcite Coatings On Fossil Vertebrates, B. A.O. Huiming, Paul L. Koch, Robert P. Hepple

Faculty Publications

Hematite coatings are common on vertebrate fossils from Paleocene/Eocene paleosol deposits in the Bighorn Basin, Wyoming. In general, hematite coatings are found only on fossils and are limited to soils exhibiting hydromorphic features and moderate maturity. Pétrographie and isotopic evidence suggests that hematite and micritic calcite formed at nearly the same time in a pedogenic environment, whereas sparry calcite formed later at greater burial depths. The parent material of paleosols is rich in iron, supplying an ample source of iron for hematite formation. Decomposition of animal tissues around bones may enhance the weathering of iron-bearing minerals in soils surrounding carcasses, …

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Antarctic Paleolake Sediments And The Search For Extinct Life On Mars, Peter T. Doran, Robert A. Wharton, David J. Des Marais, Christopher P. Mckay Jan 1998

Antarctic Paleolake Sediments And The Search For Extinct Life On Mars, Peter T. Doran, Robert A. Wharton, David J. Des Marais, Christopher P. Mckay

Faculty Publications

Evidence of lakes in Mars history is substantial. The proposed similarities between the ancient Martian environment and certain modem environments on Earth have led exobiologists to study antarctic lakes as analogs to those purported to have existed on Mars. We have investigated modem sedimentation processes (especially with respect to δ13C of carbonate and organic matter) in lakes in the McMurdo Dry Valleys region of east Antarctica and assessed various paleolakc deposits with respect to their utility as Martian analogs and targets for future Mars exobiology missions. Three main types of paleolake deposit were identified and assessed: strand lines, perched deltas, …

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Monophyletic Subgroups Of The Tribe Millettieae (Leguminosae) As Revealed By Phytochrome Nucleotide Sequence Data, Matt Lavin, Elisa Eshbaugh, Jer Ming Hu, Sarah Mathews, Robert A. Sharrock Jan 1998

Monophyletic Subgroups Of The Tribe Millettieae (Leguminosae) As Revealed By Phytochrome Nucleotide Sequence Data, Matt Lavin, Elisa Eshbaugh, Jer Ming Hu, Sarah Mathews, Robert A. Sharrock

Faculty Publications

Phylogenetic analysis of phytochrome (PHY) genes reveals the identity and relationships of four PHY loci among papilionoid Leguminosae. A phylogenetic analysis of loci combined according to species suggests that most of the tribe Millettieae belongs to one of two monophyletic clades: the Derris-Lonchocarpus or the Tephrosia clade. Together these two form a monophyletic group that is sister to a lineage represented by Millettia grandis of Millettia sect. Compresso-gemmatae. Collectively, this large monophyletic group is referred to as the Millettieae-core group, which based on our sampling, includes species of Millettieae that do not accumulate the nonprotein amino acid canavanine and that …

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Molecular Cloning And Hormonal Regulation Of A Murine Epididymal Retinoic Acid-Binding Protein Messenger Ribonucleic Acid, Jean Jacques Lareyre, Weng Li Zheng, Guang Quan Zhao, Susan Kasper, Marcia E. Newcomer, Robert J. Matusik, David E. Ong, Marie Claire Orgebin-Crist Jan 1998

Molecular Cloning And Hormonal Regulation Of A Murine Epididymal Retinoic Acid-Binding Protein Messenger Ribonucleic Acid, Jean Jacques Lareyre, Weng Li Zheng, Guang Quan Zhao, Susan Kasper, Marcia E. Newcomer, Robert J. Matusik, David E. Ong, Marie Claire Orgebin-Crist

Faculty Publications

A complementary DNA encoding the mouse epididymal secretory protein MEP 10 (mouse epididymal protein 10) was cloned and is now renamed murine epididymal retinoic acid binding protein (mE-RABP). The analysis of the predicted primary amino acid sequence showed that mE-RABP has a 75% identity with rat ESP I (epididymal secretory protein I), another epididymal retinoic acid-binding protein. The homology strongly suggests that mE-RABP is the mouse orthologue of rat ESP I. A computer analysis of the predicted three- dimensional structure confirmed that mE-RABP can accommodate retinoic acid as ligand. In the rat, ESP I messenger RNA (mRNA) is expressed in …

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The Intracellular Localization Of Ribulose-1,5-Bisphosphate Carboxylase/Oxygenase In Chlamydomonas Reinhardtii, Olga N. Borkhsenious, Catherine B. Mason, James V. Moroney Jan 1998

The Intracellular Localization Of Ribulose-1,5-Bisphosphate Carboxylase/Oxygenase In Chlamydomonas Reinhardtii, Olga N. Borkhsenious, Catherine B. Mason, James V. Moroney

Faculty Publications

The pyrenoid is a proteinaceous structure found in the chloroplast of most unicellular algae. Various studies indicate that ribulose-1,5-bisphosphate carboxylase/oxygenase (Rubisco) is present in the pyrenoid, although the fraction of Rubisco localized there remains controversial. Estimates of the amount of Rubisco in the pyrenoid of Chlamydomonas reinhardtii range from 5% to nearly 100%. Using immunolocalization, the amount of Rubisco localized to the pyrenoid or to the chloroplast stroma was estimated for C. reinhardtii cells grown under different conditions. It was observed that the amount of Rubisco in the pyrenoid varied with growth condition; about 40% was in the pyrenoid when …

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Methanol Promotes Atmospheric Methane Oxidation By Methanotrophic Cultures And Soils?, J. Benstead, G. M. King, H. G. Williams Jan 1998

Methanol Promotes Atmospheric Methane Oxidation By Methanotrophic Cultures And Soils?, J. Benstead, G. M. King, H. G. Williams

Faculty Publications

Two methanotrophic bacteria, Methylobacter albus BG8 and Methylosinus trichosporium OB3b, oxidized atmospheric methane during batch growth on methanol. Methane consumption was rapidly and substantially diminished (95% over 9 days) when washed cell suspensions were incubated without methanol in the presence of atmospheric methane (1.7 ppm). Methanotrophic activity was stimulated after methanol (10 mM) but not methane (1,000 ppm) addition. M. albus BG8 grown in continuous culture for 80 days with methanol retained the ability to oxidize atmospheric methane and oxidized methane in a chemostat air supply. Methane oxidation during growth on methanol was not affected by methane deprivation. Differences in …

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Transformation And Transport Of Inorganic Nitrogen In Sediments Of A Southeast Asian Mangrove Forest, Erik Kristensen, Mikael H. Jensen, Gary T. Banta, Kim Hansen, Marianne Holmer, Gary M. King Jan 1998

Transformation And Transport Of Inorganic Nitrogen In Sediments Of A Southeast Asian Mangrove Forest, Erik Kristensen, Mikael H. Jensen, Gary T. Banta, Kim Hansen, Marianne Holmer, Gary M. King

Faculty Publications

The most important inorganic nitrogen transformations (nitrification, denitrification and N fixation) and DIN fluxes in darkened and inundated sediments were studied during the dry season in the Ao Nam Bor mangrove forest at the island of Phuket, Thailand. Dark fluxes of NH4+ were low (not significantly different from zero) and tended to be directed into the sediment in the area vegetated by the tree Rhizophora apiculata (204 μmol m-2 d-1) and out of the sediment in an adjacent unvegetated area (80 μmol m-2 d-1), NO3- appeared to be taken up by the sediment in both areas, although at rates not …

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Identification Of A Class Of Chromatin Boundary Elements, Olivier Cuvier, Craig M. Hart, Ulrich K. Laemmli Jan 1998

Identification Of A Class Of Chromatin Boundary Elements, Olivier Cuvier, Craig M. Hart, Ulrich K. Laemmli

Faculty Publications

Boundary elements are thought to define the ends of functionally independent domains of genetic activity. An assay for boundary activity based on this concept measures the ability to insulate a bracketed, chromosomally integrated reporter gene from position effects. Despite their presumed importance, the few examples identified to date apparently do not share sequence motifs or DNA binding proteins. The Drosophila protein BEAF binds the scs' boundary element of the 87A7 hsp70 locus and roughly half of polytene chromosome interband loci. To see if these sites represent a class of boundary elements that have BEAF in common, we have isolated and …

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Sympatric Sea Shells Along The Sea's Shore: The Geography Of Speciation In The Marine Gastropod Tegula, Michael E. Hellberg Jan 1998

Sympatric Sea Shells Along The Sea's Shore: The Geography Of Speciation In The Marine Gastropod Tegula, Michael E. Hellberg

Faculty Publications

Uncertainty and controversy surround the geographical and ecological circumstances that create genetic differences between populations that eventually lead to reproductive isolation. Two aspects of marine organisms further complicate this situation: (1) many species possess planktonic larvae capable of great dispersal; and (2) obvious barriers to movement between populations are rare. Past studies of speciation in the sea have focussed on identifying the effects of past land barriers and on biogeographical breakpoints. However, assessing the role such undeniable barriers actually play in the initial divergence leading to reproductive isolation requires phylogenetic studies of recent radiations living in varying degrees of sympatry …

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Race And Hypertension: Science And Nescience, R. S. Cooper, J. S. Kaufman Jan 1998

Race And Hypertension: Science And Nescience, R. S. Cooper, J. S. Kaufman

Faculty Publications

No abstract provided.

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Emergence Of Western Diseases In The Tropical World: The Experience With Chronic Cardiovascular Diseases, Terrence Forrester, Richard S. Cooper, David Weatherall Jan 1998

Emergence Of Western Diseases In The Tropical World: The Experience With Chronic Cardiovascular Diseases, Terrence Forrester, Richard S. Cooper, David Weatherall

Faculty Publications

Our knowledge of the disease burden components of tropical populations is fragmentary. Historically, the infectious diseases have been emphasized but, as some populations have undergone socio-economic changes, vital statistics have described a change in the pattern of disease. The picture is of a decline in infectious and a rise in chronic non-communicable disease. We focus here on the emergence of chronic cardiovascular diseases, and use hypertension as the paradigmic example. Early blood pressure surveys showed a virtual absence of hypertension among rural Africans and moderate prevalences in the Caribbean. Prevalence was highest among US and UK blacks. In a recent …

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Feeding Habits And Gut Fauna Of Zootermopsis Angusticollis (Isoptera: Termopsidae) In Response To Wood Species And Fungal Associates, M. E. Mankowski, T. D. Schowalter, J. J. Morrell, B. Lyons Jan 1998

Feeding Habits And Gut Fauna Of Zootermopsis Angusticollis (Isoptera: Termopsidae) In Response To Wood Species And Fungal Associates, M. E. Mankowski, T. D. Schowalter, J. J. Morrell, B. Lyons

Faculty Publications

Feeding preferences and consumption were evaluated to measure rate of wood consumption and the response of the gut fauna of Zootermopsis angusticollis to 4 conifers and 2 fungal species. In both choice and forced-feeding tests, exposure to Trichoderma viride Pers.:Fr. reduced consumption of Douglas-fir [Pseudotsuga menziesii (Mirb.) Franco] and western hemlock [Tsuga heterophylla (Raf.) Sarg.] but did not affect noble fir (Abies procera Rehd.) or western redcedar (Thuja plicata Donn ex D. Don). Exposure to Stereum sanguinolentum Albertini & Schwein.:Fr. increased consumption of Douglas-fir but reduced consumption of western hemlock in a choice feeding test and increased consumption of Douglas-fir …

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