Browsing by Subject "University of Southern California"

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    Biogeochemical patterns and processes in buoyant, deep-sea hydrothermal plumes
    (2011-08-11) Wendt, Kathleen
    Along the global mid-ocean ridge, sub-seafloor hydrothermal circulation results in the exchange of heat and chemical species between seawater and the ocean crust. The resulting thermally and geochemically altered fluids are vented at the seafloor. The mixing of cold, oxic deep-ocean waters with hydrothermal fluids creates plumes with physically and chemically dynamic features. Hydrothermal plumes represent a globally distributed interface where marine hydrothermal circulation exerts its biogeochemical influence on elemental budgets of ocean basins. The goal of the present study is to describe the microbiological niches created by physical and geochemical gradients in plumes. One of our central hypotheses is that microorganisms respond to and alter the geochemistry of hydrothermal plumes. To achieve this goal and test our hypothesis, a field study was undertaken at the Eastern Lau Spreading Center (ELSC). While multiple vent sites along the ELSC are included in the larger study, here we report on an integrated, biogeochemical investigation of a single buoyant plume within ABE vent field. A series of replicate sample sets were collected by in situ filtration at 0.5m, 40m, 200m within a buoyant plume using the ROV JASON. Above plume background and near bottom background sample sets were also collected. Hydrothermal plume particles in sample replicates or splits have been queried for bulk geochemistry, particle-by-particle mineralogy, and microbial community composition. These three data streams are being evaluated individually to characterize the geochemical and microbiological changes throughout the plume with respect to above and below plume backgrounds. In addition, an iterative and integrated analysis is being used to compare: (1) calculated mineralogy to direct measurements; and (2) predicted energy yields from chemoautotrophy to observed microbial composition.
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    Oral history interview with Sidney Michel Rubens
    (Charles Babbage Institute, 1986-01) Rubens, Sidney Michel
    Rubens discusses his career through his employment with Engineering Research Associates (ERA). He reviews his education in physics at the University of Washington, his work in ionization techniques, and his teaching position at UCLA beginning in 1937. In 1940, he joined the Naval Ordnance Laboratory, where he developed magnetic mine detection devices. There he met Howard Engstrom, Robert Gutterman, Howard Daniels, and William Norris. In 1945, under the sponsorship of the Office of Naval Research, this group formed ERA to continue their war-time work, and Rubens joined them in 1946. He first worked on magnetic techniques for computer storage as part of the Goldberg project, under the direction of John Coombs and C. B. Tompkins. Rubens discusses the magnetic tape equipment he used, some of which was war-time capture from German laboratories. He also discusses his contacts with the University of Minnesota computer center.