3,697 research outputs found

    Feeding IC 342: The nuclear spiral of a starburst galaxy

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    IC 342 is a large nearby (1.8 Mpc, Turner and Hurt, 1991, hereafter T&H) spiral galaxy undergoing a moderate nuclear starburst. T&H have previously mapped the inner arcminute in CO-13(1-0) using the Owens Valley Millimeter Interferometer and found evidence that the nuclear molecular gas takes the form of spiral arms in a density wave pattern. They suggest that radial streaming along the arms may channel gas from the exterior of the galaxy into the nucleus, feeding the starburst. We have mapped the CO-12(1-0) emission of the inner 2 kpc of IC 342 at 2.8 inch resolution using the Owens Valley Radio Observatory (OVRO) Millimeter Interferometer. The greater sensitivity of CO-12 observations has allowed us to trace the spiral pattern out to a total extent of greater than 1 kpc. The CO-12 observations extend considerably the structure observed at CO-13 and offer further evidence that a spiral density wave may extend from the disk into the nucleus of IC 342

    Do mayors run for higher office? New evidence on progressive ambition

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    The mayor’s office potentially offers a launchpad for statewide and national political ambitions. We know relatively little, however, about how frequently mayors actually run for higher office, and which mayors choose to do so. This article combines longitudinal data on the career paths of the mayors of 200 big cities with new survey and interview data to investigate these questions. While we find that individual and city traits—especially gender—have some predictive power, the overwhelming story is that relatively few mayors—just under one-fifth—ever seek higher office. We suggest that ideological, institutional, and electoral factors all help to explain why so few mayors exhibit progressive ambition

    Isolation of a Chloramphenicol-Resistant Protein From λ-Infected Cells

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    During infection with bacteriophage ϕX174, a protein, made in the presence of 30 γ chloramphenicol/ml but not made in the presence of concentrations greater than 100 γ/ml, has been shown to be essential for viral DNA replication. A protein with similar chromatographic properties and “chloramphenicol resistance” has now been demonstrated in cells infected with λ bacteriophage
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