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  • 1
    Publication Date: 2015-12-15
    Description: The dwarf planet (1) Ceres, the largest object in the main asteroid belt with a mean diameter of about 950 kilometres, is located at a mean distance from the Sun of about 2.8 astronomical units (one astronomical unit is the Earth-Sun distance). Thermal evolution models suggest that it is a differentiated body with potential geological activity. Unlike on the icy satellites of Jupiter and Saturn, where tidal forces are responsible for spewing briny water into space, no tidal forces are acting on Ceres. In the absence of such forces, most objects in the main asteroid belt are expected to be geologically inert. The recent discovery of water vapour absorption near Ceres and previous detection of bound water and OH near and on Ceres (refs 5-7) have raised interest in the possible presence of surface ice. Here we report the presence of localized bright areas on Ceres from an orbiting imager. These unusual areas are consistent with hydrated magnesium sulfates mixed with dark background material, although other compositions are possible. Of particular interest is a bright pit on the floor of crater Occator that exhibits probable sublimation of water ice, producing haze clouds inside the crater that appear and disappear with a diurnal rhythm. Slow-moving condensed-ice or dust particles may explain this haze. We conclude that Ceres must have accreted material from beyond the 'snow line', which is the distance from the Sun at which water molecules condense.〈br /〉〈span class="detail_caption"〉Notes: 〈/span〉Nathues, A -- Hoffmann, M -- Schaefer, M -- Le Corre, L -- Reddy, V -- Platz, T -- Cloutis, E A -- Christensen, U -- Kneissl, T -- Li, J-Y -- Mengel, K -- Schmedemann, N -- Schaefer, T -- Russell, C T -- Applin, D M -- Buczkowski, D L -- Izawa, M R M -- Keller, H U -- O'Brien, D P -- Pieters, C M -- Raymond, C A -- Ripken, J -- Schenk, P M -- Schmidt, B E -- Sierks, H -- Sykes, M V -- Thangjam, G S -- Vincent, J-B -- England -- Nature. 2015 Dec 10;528(7581):237-40. doi: 10.1038/nature15754.〈br /〉〈span class="detail_caption"〉Author address: 〈/span〉Max Planck Institute for Solar System Research, Goettingen, Germany. ; Planetary Science Institute, Tucson, Arizona, USA. ; University of Winnipeg, Winnipeg, Canada. ; Freie Universitaet Berlin, Berlin, Germany. ; Technische Universitaet Clausthal, Clausthal-Zellerfeld, Germany. ; University of California, Los Angeles (UCLA), Los Angeles, California, USA. ; Johns Hopkins University, Laurel, Maryland, USA. ; Royal Ontario Museum, Toronto, Canada. ; TU Braunschweig, Braunschweig, Germany. ; Brown University, Providence, Rhode Island, USA. ; Jet Propulsion Laboratory, Pasadena, California, USA. ; Lunar and Planetary Institute, Houston, Texas, USA. ; Georgia Institute of Technology, Atlanta, Georgia, USA.〈br /〉〈span class="detail_caption"〉Record origin:〈/span〉 〈a href="http://www.ncbi.nlm.nih.gov/pubmed/26659183" target="_blank"〉PubMed〈/a〉
    Print ISSN: 0028-0836
    Electronic ISSN: 1476-4687
    Topics: Biology , Chemistry and Pharmacology , Medicine , Natural Sciences in General , Physics
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  • 2
    Publication Date: 2014-10-04
    Description: The Procellarum region is a broad area on the nearside of the Moon that is characterized by low elevations, thin crust, and high surface concentrations of the heat-producing elements uranium, thorium, and potassium. The region has been interpreted as an ancient impact basin approximately 3,200 kilometres in diameter, although supporting evidence at the surface would have been largely obscured as a result of the great antiquity and poor preservation of any diagnostic features. Here we use data from the Gravity Recovery and Interior Laboratory (GRAIL) mission to examine the subsurface structure of Procellarum. The Bouguer gravity anomalies and gravity gradients reveal a pattern of narrow linear anomalies that border Procellarum and are interpreted to be the frozen remnants of lava-filled rifts and the underlying feeder dykes that served as the magma plumbing system for much of the nearside mare volcanism. The discontinuous surface structures that were earlier interpreted as remnants of an impact basin rim are shown in GRAIL data to be a part of this continuous set of border structures in a quasi-rectangular pattern with angular intersections, contrary to the expected circular or elliptical shape of an impact basin. The spatial pattern of magmatic-tectonic structures bounding Procellarum is consistent with their formation in response to thermal stresses produced by the differential cooling of the province relative to its surroundings, coupled with magmatic activity driven by the greater-than-average heat flux in the region.〈br /〉〈span class="detail_caption"〉Notes: 〈/span〉Andrews-Hanna, Jeffrey C -- Besserer, Jonathan -- Head, James W 3rd -- Howett, Carly J A -- Kiefer, Walter S -- Lucey, Paul J -- McGovern, Patrick J -- Melosh, H Jay -- Neumann, Gregory A -- Phillips, Roger J -- Schenk, Paul M -- Smith, David E -- Solomon, Sean C -- Zuber, Maria T -- England -- Nature. 2014 Oct 2;514(7520):68-71. doi: 10.1038/nature13697.〈br /〉〈span class="detail_caption"〉Author address: 〈/span〉Department of Geophysics and Center for Space Resources, Colorado School of Mines, Golden, Colorado 80401, USA. ; Department of Earth and Planetary Sciences, University of California, Santa Cruz, California 95064, USA. ; Department of Earth, Environmental and Planetary Sciences, Brown University, Providence, Rhode Island 02912, USA. ; Planetary Science Directorate, Southwest Research Institute, Boulder, Colorado 80302, USA. ; Lunar and Planetary Institute, Houston, Texas 77058, USA. ; Hawaii Institute of Geophysics and Planetology, University of Hawaii, Honolulu, Hawaii 96822, USA. ; Department of Earth, Atmospheric, and Planetary Sciences, Purdue University, West Lafayette, Indiana 47907, USA. ; Solar System Exploration Division, NASA Goddard Space Flight Center, Greenbelt, Maryland 20771, USA. ; Department of Earth, Atmospheric and Planetary Sciences, Massachusetts Institute of Technology, Cambridge, Massachusetts 02139-4307, USA. ; 1] Department of Terrestrial Magnetism, Carnegie Institution of Washington, Washington DC 20015, USA [2] Lamont-Doherty Earth Observatory, Columbia University, Palisades, New York 10964, USA.〈br /〉〈span class="detail_caption"〉Record origin:〈/span〉 〈a href="http://www.ncbi.nlm.nih.gov/pubmed/25279919" target="_blank"〉PubMed〈/a〉
    Print ISSN: 0028-0836
    Electronic ISSN: 1476-4687
    Topics: Biology , Chemistry and Pharmacology , Medicine , Natural Sciences in General , Physics
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  • 3
    Publication Date: 2011-11-18
    Description: Europa, the innermost icy satellite of Jupiter, has a tortured young surface and sustains a liquid water ocean below an ice shell of highly debated thickness. Quasi-circular areas of ice disruption called chaos terrains are unique to Europa, and both their formation and the ice-shell thickness depend on Europa's thermal state. No model so far has been able to explain why features such as Conamara Chaos stand above surrounding terrain and contain matrix domes. Melt-through of a thin (few-kilometre) shell is thermodynamically improbable and cannot raise the ice. The buoyancy of material rising as either plumes of warm, pure ice called diapirs or convective cells in a thick (〉10 kilometres) shell is insufficient to produce the observed chaos heights, and no single plume can create matrix domes. Here we report an analysis of archival data from Europa, guided by processes observed within Earth's subglacial volcanoes and ice shelves. The data suggest that chaos terrains form above liquid water lenses perched within the ice shell as shallow as 3 kilometres. Our results suggest that ice-water interactions and freeze-out give rise to the diverse morphologies and topography of chaos terrains. The sunken topography of Thera Macula indicates that Europa is actively resurfacing over a lens comparable in volume to the Great Lakes in North America.〈br /〉〈span class="detail_caption"〉Notes: 〈/span〉Schmidt, B E -- Blankenship, D D -- Patterson, G W -- Schenk, P M -- England -- Nature. 2011 Nov 16;479(7374):502-5. doi: 10.1038/nature10608.〈br /〉〈span class="detail_caption"〉Author address: 〈/span〉Institute for Geophysics, John A. & Katherine G. Jackson School of Geosciences, The University of Texas at Austin, J. J. Pickle Research Campus, Building 196 (ROC), 10100 Burnet Road (R2200), Austin, Texas 78758-4445, USA. britneys@ig.utexas.edu〈br /〉〈span class="detail_caption"〉Record origin:〈/span〉 〈a href="http://www.ncbi.nlm.nih.gov/pubmed/22089135" target="_blank"〉PubMed〈/a〉
    Print ISSN: 0028-0836
    Electronic ISSN: 1476-4687
    Topics: Biology , Chemistry and Pharmacology , Medicine , Natural Sciences in General , Physics
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  • 4
    Publication Date: 2016-03-19
    Description: NASA's New Horizons spacecraft has revealed the complex geology of Pluto and Charon. Pluto's encounter hemisphere shows ongoing surface geological activity centered on a vast basin containing a thick layer of volatile ices that appears to be involved in convection and advection, with a crater retention age no greater than ~10 million years. Surrounding terrains show active glacial flow, apparent transport and rotation of large buoyant water-ice crustal blocks, and pitting, the latter likely caused by sublimation erosion and/or collapse. More enigmatic features include tall mounds with central depressions that are conceivably cryovolcanic and ridges with complex bladed textures. Pluto also has ancient cratered terrains up to ~4 billion years old that are extensionally faulted and extensively mantled and perhaps eroded by glacial or other processes. Charon does not appear to be currently active, but experienced major extensional tectonism and resurfacing (probably cryovolcanic) nearly 4 billion years ago. Impact crater populations on Pluto and Charon are not consistent with the steepest impactor size-frequency distributions proposed for the Kuiper belt.〈br /〉〈span class="detail_caption"〉Notes: 〈/span〉Moore, Jeffrey M -- McKinnon, William B -- Spencer, John R -- Howard, Alan D -- Schenk, Paul M -- Beyer, Ross A -- Nimmo, Francis -- Singer, Kelsi N -- Umurhan, Orkan M -- White, Oliver L -- Stern, S Alan -- Ennico, Kimberly -- Olkin, Cathy B -- Weaver, Harold A -- Young, Leslie A -- Binzel, Richard P -- Buie, Marc W -- Buratti, Bonnie J -- Cheng, Andrew F -- Cruikshank, Dale P -- Grundy, Will M -- Linscott, Ivan R -- Reitsema, Harold J -- Reuter, Dennis C -- Showalter, Mark R -- Bray, Veronica J -- Chavez, Carrie L -- Howett, Carly J A -- Lauer, Tod R -- Lisse, Carey M -- Parker, Alex Harrison -- Porter, S B -- Robbins, Stuart J -- Runyon, Kirby -- Stryk, Ted -- Throop, Henry B -- Tsang, Constantine C C -- Verbiscer, Anne J -- Zangari, Amanda M -- Chaikin, Andrew L -- Wilhelms, Don E -- New Horizons Science Team -- New York, N.Y. -- Science. 2016 Mar 18;351(6279):1284-93. doi: 10.1126/science.aad7055.〈br /〉〈span class="detail_caption"〉Author address: 〈/span〉National Aeronautics and Space Administration (NASA) Ames Research Center, Space Science Division, Moffett Field, CA 94035, USA. jeff.moore@nasa.gov. ; Department of Earth and Planetary Sciences, Washington University in St. Louis, St. Louis, MO 63130, USA. ; Southwest Research Institute, Boulder, CO 80302, USA. ; Department of Environmental Sciences, University of Virginia, Charlottesville, VA 22904, USA. ; Lunar and Planetary Institute, Houston, TX 77058, USA. ; The SETI Institute, Mountain View, CA 94043, USA. National Aeronautics and Space Administration (NASA) Ames Research Center, Space Science Division, Moffett Field, CA 94035, USA. ; University of California, Santa Cruz, CA 95064, USA. ; National Aeronautics and Space Administration (NASA) Ames Research Center, Space Science Division, Moffett Field, CA 94035, USA. ; Johns Hopkins University Applied Physics Laboratory, Laurel, MD 20723, USA. ; Massachusetts Institute of Technology, Cambridge, MA 02139, USA. ; NASA Jet Propulsion Laboratory, Pasadena, CA 91019, USA. ; Lowell Observatory, Flagstaff, AZ 86001, USA. ; Stanford University, Stanford, CA 94305, USA. ; NASA Goddard Space Flight Center, Greenbelt, MD 20771, USA. ; The SETI Institute, Mountain View, CA 94043, USA. ; University of Arizona, Tucson, AZ 85721, USA. ; National Optical Astronomy Observatory, Tucson, AZ 85719, USA. ; Roane State Community College, Oak Ridge, TN 37830, USA. ; Planetary Science Institute, Tucson, AZ 85719, USA. ; Department of Astronomy, University of Virginia, Charlottesville, VA 22904, USA. ; Independent Science Writer, Arlington, VT 05250, USA. ; U.S. Geological Survey, Retired, Menlo Park, CA 94025, USA.〈br /〉〈span class="detail_caption"〉Record origin:〈/span〉 〈a href="http://www.ncbi.nlm.nih.gov/pubmed/26989245" target="_blank"〉PubMed〈/a〉
    Print ISSN: 0036-8075
    Electronic ISSN: 1095-9203
    Topics: Biology , Chemistry and Pharmacology , Computer Science , Medicine , Natural Sciences in General , Physics
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  • 5
    Publication Date: 2016-03-19
    Description: The New Horizons spacecraft mapped colors and infrared spectra across the encounter hemispheres of Pluto and Charon. The volatile methane, carbon monoxide, and nitrogen ices that dominate Pluto's surface have complicated spatial distributions resulting from sublimation, condensation, and glacial flow acting over seasonal and geological time scales. Pluto's water ice "bedrock" was also mapped, with isolated outcrops occurring in a variety of settings. Pluto's surface exhibits complex regional color diversity associated with its distinct provinces. Charon's color pattern is simpler, dominated by neutral low latitudes and a reddish northern polar region. Charon's near-infrared spectra reveal highly localized areas with strong ammonia absorption tied to small craters with relatively fresh-appearing impact ejecta.〈br /〉〈span class="detail_caption"〉Notes: 〈/span〉Grundy, W M -- Binzel, R P -- Buratti, B J -- Cook, J C -- Cruikshank, D P -- Dalle Ore, C M -- Earle, A M -- Ennico, K -- Howett, C J A -- Lunsford, A W -- Olkin, C B -- Parker, A H -- Philippe, S -- Protopapa, S -- Quirico, E -- Reuter, D C -- Schmitt, B -- Singer, K N -- Verbiscer, A J -- Beyer, R A -- Buie, M W -- Cheng, A F -- Jennings, D E -- Linscott, I R -- Parker, J Wm -- Schenk, P M -- Spencer, J R -- Stansberry, J A -- Stern, S A -- Throop, H B -- Tsang, C C C -- Weaver, H A -- Weigle, G E 2nd -- Young, L A -- New Horizons Science Team -- New York, N.Y. -- Science. 2016 Mar 18;351(6279):aad9189. doi: 10.1126/science.aad9189.〈br /〉〈span class="detail_caption"〉Author address: 〈/span〉Lowell Observatory, Flagstaff, AZ 86001, USA. w.grundy@lowell.edu. ; Massachusetts Institute of Technology, Cambridge, MA 02139, USA. ; NASA Jet Propulsion Laboratory, La Canada Flintridge, CA 91011, USA. ; Southwest Research Institute, Boulder, CO 80302, USA. ; NASA Ames Research Center, Space Science Division, Moffett Field, CA 94035, USA. ; NASA Ames Research Center, Space Science Division, Moffett Field, CA 94035, USA. Carl Sagan Center, SETI Institute, Mountain View, CA 94043, USA. ; NASA Goddard Space Flight Center, Greenbelt, MD 20771, USA. ; Universite Grenoble Alpes, CNRS, IPAG, F-38000 Grenoble, France. ; Department of Astronomy, University of Maryland, College Park, MD 20742, USA. ; Department of Astronomy, University of Virginia, Charlottesville, VA 22904, USA. ; Johns Hopkins University Applied Physics Laboratory, Laurel, MD 20723, USA. ; Stanford University, Stanford, CA 94305, USA. ; Lunar and Planetary Institute, Houston, TX 77058, USA. ; Space Telescope Science Institute, Baltimore, MD, USA. ; Planetary Science Institute, Mumbai, India. ; Southwest Research Institute, San Antonio, TX 28510, USA.〈br /〉〈span class="detail_caption"〉Record origin:〈/span〉 〈a href="http://www.ncbi.nlm.nih.gov/pubmed/26989260" target="_blank"〉PubMed〈/a〉
    Print ISSN: 0036-8075
    Electronic ISSN: 1095-9203
    Topics: Biology , Chemistry and Pharmacology , Computer Science , Medicine , Natural Sciences in General , Physics
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  • 6
    ISSN: 1615-6102
    Keywords: Barley yellow mosaic virus ; Cytoplasmic inclusion bodies ; Electron microscopy ; Hordeum vulgare ; Immunogold labeling ; RNA 2-encoded proteins
    Source: Springer Online Journal Archives 1860-2000
    Topics: Biology
    Notes: Summary Antisera were raised against the RNA 2-encoded proteins of 28 kDa and 70 kDa of barley yellow mosaic virus (BaYMV) by using the corresponding cDNA sequences of a German isolate for protein overexpression inEscherichia coli BL 21 and subsequent purification. The proposed processing of a 98 kDa precursor polyprotein encoded by the long open reading frame of RNA 2 to two proteins of 28 kDa and 70 kDa could be confirmed by immunoprecipitation of the in vitro transcribed and translated cDNA-clone of RNA 2 and Western blot analysis of fragmentated protein extracts of BaYMV-infected winter barley plants. In situ localisation studies of infected leaf tissue using immunogold labeling techniques for electron microscopy revealed that both viral proteins of BaYMV (RNA 2) were associated with the crystal-like cytoplasmic inclusion bodies. No other parts of the cells and no other inclusions (pinwheelstructures or aggregated virus particles) showed any gold labeling when the 28 kDa and 70 kDa antisera were used. We suppose that both RNA 2-encoded proteins take part in the formation of the crystal-like cytoplasmic inclusion bodies which are the most dominant structures in the cytoplasm of BaYMV-infected tissue. Possible functions of the 28 kDa and 70 kDa protein of BaYMV (RNA 2) are discussed.
    Type of Medium: Electronic Resource
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