Now showing items 2852-2871 of 7907

    • Genomic survey of the non-cultivatable opportunistic human pathogen, Enterocytozoon bieneusi 

      Akiyoshi, Donna E.; Morrison, Hilary G.; Lei, Shi; Feng, Xiaochuan; Zhang, Quanshun; Corradi, Nicolas; Mayanja, Harriet; Tumwine, James K.; Keeling, Patrick J.; Weiss, Louis M.; Tzipori, Saul (Public Library of Science, 2009-01-09)
      Enterocytozoon bieneusi is the most common microsporidian associated with human disease, particularly in the immunocompromised population. In the setting of HIV infection, it is associated with diarrhea and wasting syndrome. ...
    • Genomics of an extreme psychrophile, Psychromonas ingrahamii 

      Riley, Monica; Staley, James T.; Danchin, Antoine; Wang, Ting Zhang; Brettin, Thomas S.; Hauser, Loren J.; Land, Miriam L.; Thompson, Linda S. (BioMed Central, 2008-05-06)
      The genome sequence of the sea-ice bacterium Psychromonas ingrahamii 37, which grows exponentially at -12C, may reveal features that help to explain how this extreme psychrophile is able to grow at such low temperatures. ...
    • Genotypic diversity within a natural coastal bacterioplankton population 

      Thompson, Janelle R.; Pacocha, Sarah E.; Pharino, Chanathip; Klepac-Ceraj, Vanja; Hunt, Dana E.; Benoit, Jennifer; Sarma-Rupavtarm, Ramahi; Distel, Daniel L.; Polz, Martin F. (2005-01-04)
      The genomic diversity and relative importance of unique genotypes within natural bacterial populations has remained largely unknown. Here, we analyze the diversity and annual dynamics of a group of coastal bacterioplankton ...
    • Geoacoustic inversion by mode amplitude perturbation 

      Poole, Travis L. (Massachusetts Institute of Technology and Woods Hole Oceanographic Institution, 2007-02)
      This thesis introduces an algorithm for inverting for the geoacoustic properties of the seafloor in shallow water. The input data required by the algorithm are estimates of the amplitudes of the normal modes excited by ...
    • Geoacoustic inversion by mode amplitude perturbation 

      Poole, Travis L.; Frisk, George V.; Lynch, James F.; Pierce, Allan D. (Acoustical Society of America, 2008-02)
      This paper introduces a perturbative inversion algorithm for determining sea floor acoustic properties, which uses modal amplitudes as input data. Perturbative inverse methods have been used in the past to estimate bottom ...
    • Geoacoustic inversion by mode amplitude perturbation 

      Poole, Travis L.; Frisk, George V.; Lynch, James F.; Pierce, Allan D. (Acoustical Society of America, 2008-02)
      This paper introduces a perturbative inversion algorithm for determining sea floor acoustic properties, which uses modal amplitudes as input data. Perturbative inverse methods have been used in the past to estimate bottom ...
    • Geoacoustic inversion in laterally varying shallow-water environments using high-resolution wavenumber estimation 

      Becker, Kyle M. (Massachusetts Institute of Technology and Woods Hole Oceanographic Institution, 2002-02)
      Sound propagation in shallow water is highly dependent on the interaction of the sound field with the bottom. In order to fully understand this problem, it is necessary to obtain reliable estimates of bottom geoacoustic ...
    • Geobiology of marine magnetotactic bacteria 

      Simmons, Sheri L. (Massachusetts Institute of Technology and Woods Hole Oceanographic Institution, 2006-06)
      Magnetotactic bacteria (MTB) biomineralize intracellular membrane-bound crystals of magnetite (Fe3O4) or greigite (Fe3S4), and are abundant in the suboxic to anoxic zones of stratified marine environments worldwide. Their ...
    • Geochemical and fluid dynamic investigations into the nature of chemical heterogeneity in the Earth's mantle 

      Hauri, Erik H. (Massachusetts Institute of Technology and Woods Hole Oceanographic Institution, 1992-09)
      Variations in the abundances of elements and radiogenic isotopes in mantle derived peridotites and volcanic rocks are chemical integrals over time, space, and process, which ultimately contain information about the role ...
    • Geochemical and physical sources of radon variation in a subterranean estuary — implications for groundwater radon activities in submarine groundwater discharge studies 

      Dulaiova, Henrieta; Gonneea, Meagan E.; Henderson, Paul B.; Charette, Matthew A. (2007-12-13)
      Submarine groundwater discharge (SGD), in form of springs and diffuse seepage, has long been recognized as a source of chemical constituents to the coastal ocean. Because groundwater is two to four orders of magnitude ...
    • Geochemical and rheological constraints on the dynamics of the oceanic upper mantle 

      Warren, Jessica M. (Massachusetts Institute of Technology and Woods Hole Oceanographic Institution, 2007-09)
      I provide constraints on mantle convection through observations of the rheology and composition of the oceanic upper mantle. Convection cannot be directly observed, yet is a fundamental part of the plate tectonic cycle. ...
    • Geochemical characterization of endmember mantle components 

      Workman, Rhea K. (Massachusetts Institute of Technology and Woods Hole Oceanographic Institution, 2005-06)
      This thesis uses trace elements and radiogenic isotope tracers to define elemental abundances in reservoirs of the Earth's mantle, including EM2 (the Enriched Mantle 2), as seen in the Samoan hotspot track, and DMM (the ...
    • Geochemical cycling of silver in marine sediments along an offshore transect 

      Morford, Jennifer L.; Kalnejais, Linda H.; Helman, Peter; Yen, Gloria; Reinard, Melissa (2008-02-08)
      Although there have been many surface water and water column silver (Ag) analyses in the ocean, the absence of high resolution pore water and solid phase Ag profiles has hampered our understanding of its oceanic geochemical ...
    • Geochemical evidence (C, N and Pb isotopes) of recent anthropogenic impact in south-central Chile from two environmentally distinct lake sediment records 

      Fagel, Nathalie; Bertrand, Sebastien; Mattielli, Nadine; Gilson, Delphine; Chirinos, Luis; Lepoint, Gilles; Urrutia, Roberto (2009-10-29)
      In this paper, we compare the elemental and isotopic (C, N, Pb) geochemistry of lake sediments from two contrasted environments in South-Central Chile. The first lake, Laguna Chica de San Pedro (LCSP), is situated in the ...
    • Geochemical evidence in the northeast Lau Basin for subduction of the Cook-Austral volcanic chain in the Tonga Trench 

      Price, Allison A.; Jackson, Matthew G.; Blichert-Toft, Janne; Blusztajn, Jerzy S.; Conatser, Christopher S.; Konter, Jasper; Koppers, Anthony; Kurz, Mark D. (John Wiley & Sons, 2016-05-13)
      Lau Basin basalts host an array of geochemical signatures that suggest incorporation of enriched mantle source material often associated with intraplate hotspots, but the origin of these signatures remain uncertain. ...
    • Geochemical proxies of North American freshwater routing during the Younger Dryas cold event 

      Carlson, Anders E.; Clark, Peter U.; Haley, Brian A.; Klinkhammer, Gary P.; Simmons, Kathleen; Brook, Edward J.; Meissner, Katrin J. (2006-12-19)
      The Younger Dryas cold interval represents a time when much of the Northern Hemisphere cooled from ~12.9 to 11.5 kiloyears before present. The cause of this event, which has long been viewed as the canonical example of ...
    • Geochemical record of Holocene to Recent sedimentation on the Western Indus continental shelf, Arabian Sea 

      Limmer, David R.; Boning, Philipp; Giosan, Liviu; Ponton, Camilo; Kohler, Cornelia M.; Cooper, Matthew J.; Tabrez, Ali R.; Clift, Peter D. (American Geophysical Union, 2012-01-14)
      We present a multiproxy geochemical analysis of two cores recovered from the Indus Shelf spanning the Early Holocene to Recent (<14 ka). Indus-23 is located close to the modern Indus River, while Indus-10 is positioned ...
    • Geochemical signatures in otoliths record natal origins of American shad 

      Walther, Benjamin D.; Thorrold, Simon R.; Olney, John E. (American Fisheries Society, 2008-01-03)
      Population connectivity is a critical component in the life history dynamics of anadromous fishes and in the persistence of local populations. We used geochemical signatures in the otoliths of American shad Alosa sapidissima ...
    • Geochemical stages at Jasper Seamount and the origin of intraplate volcanoes 

      Konter, Jasper G.; Staudigel, Hubert; Blichert-Toft, Janne; Hanan, B. B.; Polve, M.; Davies, G. R.; Shimizu, Nobumichi; Schiffman, P. (American Geophysical Union, 2009-02-03)
      Ocean intraplate volcanoes (OIVs) are formed in a sequence of stages, from large to small, that involve a systematic progression in mantle melting in terms of volumes and melt fractions with concomitant distinct mantle ...
    • Geochemical tools and paleoclimate clues : multi-molecular and isotopic investigations of tropical marine sediments and alpine ice 

      Makou, Matthew C. (Massachusetts Institute of Technology and Woods Hole Oceanographic Institution, 2006-02)
      South American climate has undergone dramatic changes since the last glacial period, as evidenced from Cariaco Basin (Venezuelan coast) and Peru Margin marine sediment biomarker records. Compounds derived from vascular ...