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Russell CT, Raymond CA, Ammannito E, Buczkowski DL, De Sanctis MC, Hiesinger H, Jaumann R, Konopliv AS, McSween HY, Nathues A, Park RS, Pieters CM, Prettyman TH, McCord TB, McFadden LA, Mottola S, Zuber MT, Joy SP, Polanskey C, Rayman MD, Castillo-Rogez JC, Chi PJ, Combe JP, Ermakov A, Fu RR, Hoffmann M, Jia YD, King SD, Lawrence DJ, Li JY, Marchi S, Preusker F, Roatsch T, Ruesch O, Schenk P, Villarreal MN, Yamashita N. Dawn arrives at Ceres: Exploration of a small, volatile-rich world. Science 2017; 353:1008-1010. [PMID: 27701107 DOI: 10.1126/science.aaf4219] [Citation(s) in RCA: 161] [Impact Index Per Article: 23.0] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 02/04/2016] [Accepted: 07/13/2016] [Indexed: 11/02/2022]
Abstract
On 6 March 2015, Dawn arrived at Ceres to find a dark, desiccated surface punctuated by small, bright areas. Parts of Ceres' surface are heavily cratered, but the largest expected craters are absent. Ceres appears gravitationally relaxed at only the longest wavelengths, implying a mechanically strong lithosphere with a weaker deep interior. Ceres' dry exterior displays hydroxylated silicates, including ammoniated clays of endogenous origin. The possibility of abundant volatiles at depth is supported by geomorphologic features such as flat crater floors with pits, lobate flows of materials, and a singular mountain that appears to be an extrusive cryovolcanic dome. On one occasion, Ceres temporarily interacted with the solar wind, producing a bow shock accelerating electrons to energies of tens of kilovolts.
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Affiliation(s)
- C T Russell
- Earth Planetary and Space Sciences, University of California, Los Angeles, 603 Charles Young Drive, Los Angeles, CA 90095-1567, USA.
| | - C A Raymond
- Jet Propulsion Laboratory, California Institute of Technology, Pasadena, CA 91109-8099, USA
| | - E Ammannito
- Earth Planetary and Space Sciences, University of California, Los Angeles, 603 Charles Young Drive, Los Angeles, CA 90095-1567, USA
| | - D L Buczkowski
- Johns Hopkins University Applied Physics Laboratory, Laurel, MD 20723-6099, USA
| | - M C De Sanctis
- Istituto di Astrofisica e Planetologia Spaziali, Istituto Nazionale di Astrofisica, 00133 Roma, Italy
| | - H Hiesinger
- Institut für Planetologie, 48149 Münster, Germany
| | - R Jaumann
- Deutsches Zentrum fur Luft-und Raumfahrt, Institute of Planetary Research, 12489 Berlin, Germany
| | - A S Konopliv
- Jet Propulsion Laboratory, California Institute of Technology, Pasadena, CA 91109-8099, USA
| | - H Y McSween
- Department of Earth and Planetary Sciences, University of Tennessee, Knoxville, TN 37996-1410, USA
| | - A Nathues
- Max-Planck-Institut für Sonnensystemforschung, Justus-von-Liebig-Weg 3, 37077 Göttingen, Germany
| | - R S Park
- Jet Propulsion Laboratory, California Institute of Technology, Pasadena, CA 91109-8099, USA
| | - C M Pieters
- Brown University, Department of Earth, Environmental, and Planetary Sciences, Providence, RI 02912, USA
| | | | - T B McCord
- The Bear Fight Institute, Winthrop, WA 98862, USA
| | - L A McFadden
- NASA Goddard Space Flight Center, Greenbelt, MD 20771, USA
| | - S Mottola
- Deutsches Zentrum fur Luft-und Raumfahrt, Institute of Planetary Research, 12489 Berlin, Germany
| | - M T Zuber
- Massachussetts Institute of Technology, Cambridge, MA 02139, USA
| | - S P Joy
- Earth Planetary and Space Sciences, University of California, Los Angeles, 603 Charles Young Drive, Los Angeles, CA 90095-1567, USA
| | - C Polanskey
- Jet Propulsion Laboratory, California Institute of Technology, Pasadena, CA 91109-8099, USA
| | - M D Rayman
- Jet Propulsion Laboratory, California Institute of Technology, Pasadena, CA 91109-8099, USA
| | - J C Castillo-Rogez
- Jet Propulsion Laboratory, California Institute of Technology, Pasadena, CA 91109-8099, USA
| | - P J Chi
- Earth Planetary and Space Sciences, University of California, Los Angeles, 603 Charles Young Drive, Los Angeles, CA 90095-1567, USA
| | - J P Combe
- The Bear Fight Institute, Winthrop, WA 98862, USA
| | - A Ermakov
- Massachussetts Institute of Technology, Cambridge, MA 02139, USA
| | - R R Fu
- Lamont-Doherty Earth Observatory, Columbia University, Palisades, NY 10968, USA
| | - M Hoffmann
- Max-Planck-Institut für Sonnensystemforschung, Justus-von-Liebig-Weg 3, 37077 Göttingen, Germany
| | - Y D Jia
- Earth Planetary and Space Sciences, University of California, Los Angeles, 603 Charles Young Drive, Los Angeles, CA 90095-1567, USA
| | - S D King
- Virginia Tech, Geosciences, Blacksburg, VA 24061, USA
| | - D J Lawrence
- Johns Hopkins University Applied Physics Laboratory, Laurel, MD 20723-6099, USA
| | - J-Y Li
- Planetary Science Institute, Tucson, AZ 85719, USA
| | - S Marchi
- Southwest Research Institute, Boulder, CO 80302, USA
| | - F Preusker
- Deutsches Zentrum fur Luft-und Raumfahrt, Institute of Planetary Research, 12489 Berlin, Germany
| | - T Roatsch
- Deutsches Zentrum fur Luft-und Raumfahrt, Institute of Planetary Research, 12489 Berlin, Germany
| | - O Ruesch
- NASA Goddard Space Flight Center, Greenbelt, MD 20771, USA
| | - P Schenk
- Lunar and Planetary Institute, Houston, TX 77058, USA
| | - M N Villarreal
- Earth Planetary and Space Sciences, University of California, Los Angeles, 603 Charles Young Drive, Los Angeles, CA 90095-1567, USA
| | - N Yamashita
- Planetary Science Institute, Tucson, AZ 85719, USA
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Wang BL, Yang R, Wang J, Jia YD, Wang GT. [Clinical effect analysis of endovascular repair for aortic pseudoaneurysms in 13 cases]. Zhonghua Yi Xue Za Zhi 2017; 97:127-130. [PMID: 28088958 DOI: 10.3760/cma.j.issn.0376-2491.2017.02.010] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [Subscribe] [Scholar Register] [Indexed: 11/05/2022]
Abstract
Objective: To discuss the clinical safety and efficacyof endovascular aneurysm repair (EVAR) for aortic pseudoaneurysms. Methods: From October 2008 to October 2015, 13 patients (11 male, 2 female, with a mean age of 55.6) with aortic pseudoaneurysms treated by EVAR wereenrolled. All the 13 casesunderwentcomputed tomographic arteriography (CTA). The etiology diagnosis withdescendingaortic pseudoaneurysms, infected abdominal aortic pseudoaneurysms, abdominal aortic pseudoaneurysmsin Behcet's syndrome, and uncertain reasons were 4, 4, 4, and 1 case, respectively. Results: In this group, 14 stentswere planted.All the patients hadno accidents and complications in perioperative period.Twelve patients were successfully followed up, 1 patient died of recurrent abdominal aortic pseudoaneurysmsin Behcet's syndrome, and 1 patient with recurrent infected abdominal aortic pseudoaneurysm wascured by pseudoaneurysm resection and extra-anatomic bypass grafting. Concluson: EVAR is a safe and effective option for aortic pseudoaneurysms.
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Affiliation(s)
- B L Wang
- Department of Vascular Surgery, Yuncheng Central Hospital, Yuncheng 044000, China
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Wang YW, Bian XL, Wu SW, Hussain I, Jia YD, Yi J, Wang G. Rate dependent of strength in metallic glasses at different temperatures. Sci Rep 2016; 6:27747. [PMID: 27270688 PMCID: PMC4897709 DOI: 10.1038/srep27747] [Citation(s) in RCA: 11] [Impact Index Per Article: 1.4] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 12/22/2015] [Accepted: 05/23/2016] [Indexed: 11/09/2022] Open
Abstract
The correlation between the strength at the macroscale and the elastic deformation as well as shear cracking behavior at the microscale of bulk metallic glasses (BMGs) is investigated. The temperatures of 298 K and 77 K as well as the strain rate ranging from 10−6 s−1 to 10−2 s−1 are applied to the BMGs, in which the mechanical responses of the BMGs are profiled through the compression tests. The yield strength is associated with the activation of the elementary deformation unit, which is insensitive to the strain rate. The maximum compressive strength is linked to the crack propagation during shear fracture process, which is influenced by the strain rate. The cryogenic temperature of 77 K significantly improves the yield strength and the maximum compressive strength of the BMGs.
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Affiliation(s)
- Y W Wang
- Laboratory for Microstructures, Institute of Materials, Shanghai University, Shanghai 200444, China
| | - X L Bian
- Laboratory for Microstructures, Institute of Materials, Shanghai University, Shanghai 200444, China
| | - S W Wu
- Laboratory for Microstructures, Institute of Materials, Shanghai University, Shanghai 200444, China
| | - I Hussain
- Laboratory for Microstructures, Institute of Materials, Shanghai University, Shanghai 200444, China
| | - Y D Jia
- Laboratory for Microstructures, Institute of Materials, Shanghai University, Shanghai 200444, China
| | - J Yi
- Laboratory for Microstructures, Institute of Materials, Shanghai University, Shanghai 200444, China
| | - G Wang
- Laboratory for Microstructures, Institute of Materials, Shanghai University, Shanghai 200444, China
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