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Scott DA, Phan TD. Can lessons be learned from reviewing peri-operative cardiac arrests? Anaesthesia 2024; 79:3-6. [PMID: 37975192 DOI: 10.1111/anae.16180] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Key Words] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Accepted: 10/19/2023] [Indexed: 11/19/2023]
Affiliation(s)
- D A Scott
- Department of Anaesthesia and Acute Pain Medicine, St Vincent's Hospital, Melbourne, Australia
- Department of Critical Care, Melbourne Medical School, University of Melbourne, Melbourne, Australia
| | - T D Phan
- Department of Anaesthesia and Acute Pain Medicine, St Vincent's Hospital, Melbourne, Australia
- Department of Critical Care, Melbourne Medical School, University of Melbourne, Melbourne, Australia
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2
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Hasegawa H, Denton RE, Nakamura TKM, Genestreti KJ, Phan TD, Nakamura R, Hwang K, Ahmadi N, Shi QQ, Hesse M, Burch JL, Webster JM, Torbert RB, Giles BL, Gershman DJ, Russell CT, Strangeway RJ, Wei HY, Lindqvist P, Khotyaintsev YV, Ergun RE, Saito Y. Magnetic Field Annihilation in a Magnetotail Electron Diffusion Region With Electron-Scale Magnetic Island. J Geophys Res Space Phys 2022; 127:e2022JA030408. [PMID: 36248013 PMCID: PMC9541864 DOI: 10.1029/2022ja030408] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [Key Words] [Grants] [Track Full Text] [Download PDF] [Figures] [Subscribe] [Scholar Register] [Received: 02/22/2022] [Revised: 05/27/2022] [Accepted: 06/20/2022] [Indexed: 06/16/2023]
Abstract
We present observations in Earth's magnetotail by the Magnetospheric Multiscale spacecraft that are consistent with magnetic field annihilation, rather than magnetic topology change, causing fast magnetic-to-electron energy conversion in an electron-scale current sheet. Multi-spacecraft analysis for the magnetic field reconstruction shows that an electron-scale magnetic island was embedded in the observed electron diffusion region (EDR), suggesting an elongated shape of the EDR. Evidence for the annihilation was revealed in the form of the island growing at a rate much lower than expected for the standard X-type geometry of the EDR, which indicates that magnetic flux injected into the EDR was not ejected from the X-point or accumulated in the island, but was dissipated in the EDR. This energy conversion process is in contrast to that in the standard EDR of a reconnecting current sheet where the energy of antiparallel magnetic fields is mostly converted to electron bulk-flow energy. Fully kinetic simulation also demonstrates that an elongated EDR is subject to the formation of electron-scale magnetic islands in which fast but transient annihilation can occur. Consistent with the observations and simulation, theoretical analysis shows that fast magnetic diffusion can occur in an elongated EDR in the presence of nongyrotropic electron effects. We suggest that the annihilation in elongated EDRs may contribute to the dissipation of magnetic energy in a turbulent collisionless plasma.
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Affiliation(s)
- H. Hasegawa
- Institute of Space and Astronautical ScienceJapan Aerospace Exploration AgencySagamiharaJapan
| | - R. E. Denton
- Department of Physics and AstronomyDartmouth CollegeHanoverNHUSA
| | - T. K. M. Nakamura
- Space Research InstituteAustrian Academy of SciencesGrazAustria
- Institute of PhysicsUniversity of GrazGrazAustria
| | | | - T. D. Phan
- Space Sciences LaboratoryUniversity of CaliforniaBerkeleyCAUSA
| | - R. Nakamura
- Space Research InstituteAustrian Academy of SciencesGrazAustria
| | - K.‐J. Hwang
- Southwest Research InstituteSan AntonioTXUSA
| | - N. Ahmadi
- Laboratory for Atmospheric and Space PhysicsUniversity of ColoradoBoulderCOUSA
| | - Q. Q. Shi
- Shandong Provincial Key Laboratory of Optical Astronomy and Solar‐Terrestrial EnvironmentInstitute of Space SciencesShandong UniversityWeihaiChina
| | - M. Hesse
- NASA Ames Research CenterMoffett FieldCAUSA
| | - J. L. Burch
- Southwest Research InstituteSan AntonioTXUSA
| | | | - R. B. Torbert
- Institute of PhysicsUniversity of GrazGrazAustria
- Physics DepartmentUniversity of New HampshireDurhamNHUSA
| | - B. L. Giles
- NASA Goddard Space Flight CenterGreenbeltMDUSA
| | | | - C. T. Russell
- Department of Earth, Planetary, and Space SciencesUniversity of CaliforniaLos AngelesCAUSA
| | - R. J. Strangeway
- Department of Earth, Planetary, and Space SciencesUniversity of CaliforniaLos AngelesCAUSA
| | - H. Y. Wei
- Department of Earth, Planetary, and Space SciencesUniversity of CaliforniaLos AngelesCAUSA
| | | | | | - R. E. Ergun
- Department of Astrophysical and Planetary SciencesUniversity of ColoradoBoulderCOUSA
| | - Y. Saito
- Institute of Space and Astronautical ScienceJapan Aerospace Exploration AgencySagamiharaJapan
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3
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Phan TD, Verniero JL, Larson D, Lavraud B, Drake JF, Øieroset M, Eastwood JP, Bale SD, Livi R, Halekas JS, Whittlesey PL, Rahmati A, Stansby D, Pulupa M, MacDowall RJ, Szabo PA, Koval A, Desai M, Fuselier SA, Velli M, Hesse M, Pyakurel PS, Maheshwari K, Kasper JC, Stevens JM, Case AW, Raouafi NE. Parker Solar Probe Observations of Solar Wind Energetic Proton Beams Produced by Magnetic Reconnection in the Near-Sun Heliospheric Current Sheet. Geophys Res Lett 2022; 49:e2021GL096986. [PMID: 35864893 PMCID: PMC9286436 DOI: 10.1029/2021gl096986] [Citation(s) in RCA: 1] [Impact Index Per Article: 0.5] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [Key Words] [Grants] [Track Full Text] [Subscribe] [Scholar Register] [Received: 11/09/2021] [Revised: 03/21/2022] [Accepted: 03/30/2022] [Indexed: 06/09/2023]
Abstract
We report observations of reconnection exhausts in the Heliospheric Current Sheet (HCS) during Parker Solar Probe Encounters 08 and 07, at 16 R s and 20 R s , respectively. Heliospheric current sheet (HCS) reconnection accelerated protons to almost twice the solar wind speed and increased the proton core energy by a factor of ∼3, due to the Alfvén speed being comparable to the solar wind flow speed at these near-Sun distances. Furthermore, protons were energized to super-thermal energies. During E08, energized protons were found to have leaked out of the exhaust along separatrix field lines, appearing as field-aligned energetic proton beams in a broad region outside the HCS. Concurrent dropouts of strahl electrons, indicating disconnection from the Sun, provide further evidence for the HCS being the source of the beams. Around the HCS in E07, there were also proton beams but without electron strahl dropouts, indicating that their origin was not the local HCS reconnection exhaust.
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Affiliation(s)
- T. D. Phan
- SSLUniversity of CaliforniaBerkeleyCAUSA
| | | | - D. Larson
- SSLUniversity of CaliforniaBerkeleyCAUSA
| | - B. Lavraud
- Laboratoire d'Astrophysique de BordeauxUniversity BordeauxPessacFrance
- IRAPCNRSCNESUniversité de ToulouseToulouseFrance
| | | | | | | | - S. D. Bale
- SSLUniversity of CaliforniaBerkeleyCAUSA
- Physics DepartmentUniversity of CaliforniaBerkeleyCAUSA
| | - R. Livi
- SSLUniversity of CaliforniaBerkeleyCAUSA
| | | | | | - A. Rahmati
- SSLUniversity of CaliforniaBerkeleyCAUSA
| | - D. Stansby
- Mullard Space Science LaboratoryUniversity College LondonDorkingUK
| | - M. Pulupa
- SSLUniversity of CaliforniaBerkeleyCAUSA
| | | | - P. A. Szabo
- NASA Goddard Space Flight CenterGreenbeltMDUSA
| | - A. Koval
- NASA Goddard Space Flight CenterGreenbeltMDUSA
- University of MarylandBaltimore CountyBaltimoreMDUSA
| | - M. Desai
- Southwest Research InstituteSan AntonioTXUSA
| | | | - M. Velli
- University of CaliforniaLos AngelesCAUSA
| | - M. Hesse
- NASA Ames Research CenterMoffett FieldCAUSA
| | | | | | - J. C. Kasper
- Climate and Space Sciences and EngineeringUniversity of MichiganAnn ArborMIUSA
| | | | - A. W. Case
- Smithsonian Astrophysical ObservatoryCambridgeMAUSA
| | - N. E. Raouafi
- Johns Hopkins University Applied Physics LaboratoryLaurelMDUSA
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4
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Pyakurel PS, Shay MA, Drake JF, Phan TD, Cassak PA, Verniero JL. Faster Form of Electron Magnetic Reconnection with a Finite Length X-Line. Phys Rev Lett 2021; 127:155101. [PMID: 34677989 DOI: 10.1103/physrevlett.127.155101] [Citation(s) in RCA: 1] [Impact Index Per Article: 0.3] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [Track Full Text] [Subscribe] [Scholar Register] [Received: 03/30/2021] [Accepted: 09/13/2021] [Indexed: 06/13/2023]
Abstract
Observations in Earth's turbulent magnetosheath downstream of a quasiparallel bow shock reveal a prevalence of electron-scale current sheets favorable for electron-only reconnection where ions are not coupled to the reconnecting magnetic fields. In small-scale turbulence, magnetic structures associated with intense current sheets are limited in all dimensions. And since the coupling of ions are constrained by a minimum length scale, the dynamics of electron reconnection is likely to be 3D. Here, both 2D and 3D kinetic particle-in-cell simulations are used to investigate electron-only reconnection, focusing on the reconnection rate and associated electron flows. A new form of 3D electron-only reconnection spontaneously develops where the magnetic X-line is localized in the out-of-plane (z) direction. The consequence is an enhancement of the reconnection rate compared with two dimensions, which results from differential mass flux out of the diffusion region along z, enabling a faster inflow velocity and thus a larger reconnection rate. This outflow along z is due to the magnetic tension force in z just as the conventional exhaust tension force, allowing particles to leave the diffusion region efficiently along z unlike the 2D configuration.
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Affiliation(s)
- P S Pyakurel
- Space Sciences Laboratory, University of California, Berkeley, California 94720, USA
| | - M A Shay
- University of Delaware, Newark, Delaware 19716, USA
| | - J F Drake
- Department of Physics and the Institute for Physical Science and Technology, University of Maryland, College Park, Maryland 20742, USA
| | - T D Phan
- Space Sciences Laboratory, University of California, Berkeley, California 94720, USA
| | - P A Cassak
- Department of Physics and Astronomy and Center for KINETIC Plasma Physics, West Virginia University, Morgantown, West Virginia 26506, USA
| | - J L Verniero
- Space Sciences Laboratory, University of California, Berkeley, California 94720, USA
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5
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Eastwood JP, Goldman MV, Phan TD, Stawarz JE, Cassak PA, Drake JF, Newman D, Lavraud B, Shay MA, Ergun RE, Burch JL, Gershman DJ, Giles BL, Lindqvist PA, Torbert RB, Strangeway RJ, Russell CT. Energy Flux Densities near the Electron Dissipation Region in Asymmetric Magnetopause Reconnection. Phys Rev Lett 2020; 125:265102. [PMID: 33449730 DOI: 10.1103/physrevlett.125.265102] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [Track Full Text] [Subscribe] [Scholar Register] [Received: 12/30/2019] [Revised: 10/29/2020] [Accepted: 11/24/2020] [Indexed: 06/12/2023]
Abstract
Magnetic reconnection is of fundamental importance to plasmas because of its role in releasing and repartitioning stored magnetic energy. Previous results suggest that this energy is predominantly released as ion enthalpy flux along the reconnection outflow. Using Magnetospheric Multiscale data we find the existence of very significant electron energy flux densities in the vicinity of the magnetopause electron dissipation region, orthogonal to the ion energy outflow. These may significantly impact models of electron transport, wave generation, and particle acceleration.
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Affiliation(s)
- J P Eastwood
- The Blackett Laboratory, Imperial College London, London SW7 2AZ, United Kingdom
| | - M V Goldman
- Department of Physics, University of Colorado, Boulder, Colorado 80303, USA
| | - T D Phan
- Space Sciences Laboratory, University of California, Berkeley, California 94720, USA
| | - J E Stawarz
- The Blackett Laboratory, Imperial College London, London SW7 2AZ, United Kingdom
| | - P A Cassak
- Department of Physics and Astronomy and Center for KINETIC Plasma Physics, West Virginia University, Morgantown, West Virginia 26506, USA
| | - J F Drake
- Department of Physics/Institute for Physical Science and Technology, University of Maryland, College Park, Maryland 20742, USA
| | - D Newman
- Department of Physics, University of Colorado, Boulder, Colorado 80303, USA
| | - B Lavraud
- Laboratoire d'Astrophysique de Bordeaux, Univ. Bordeaux, CNRS, B18N, allée Geoffroy Saint-Hilaire, 33615 Pessac, France
- Institut de Recherche en Astrophysique et Planétologie, CNRS, CNES, Université de Toulouse, 31028 Toulouse Cedex 4, France
| | - M A Shay
- Department of Physics and Astronomy, University of Delaware, Newark, Delaware 19716, USA
| | - R E Ergun
- LASP/Department of Astrophysical and Planetary Sciences, University of Colorado, Boulder, Colorado 80303, USA
| | - J L Burch
- Southwest Research Institute, San Antonio, Texas 78238, USA
| | - D J Gershman
- NASA, Goddard Space Flight Center, Greenbelt, Maryland 20771, USA
| | - B L Giles
- NASA, Goddard Space Flight Center, Greenbelt, Maryland 20771, USA
| | - P A Lindqvist
- KTH Royal Institute of Technology, SE-100 44 Stockholm, Sweden
| | - R B Torbert
- Southwest Research Institute, San Antonio, Texas 78238, USA
- University of New Hampshire, Durham, New Hampshire 03824, USA
| | - R J Strangeway
- Institute of Geophysics, Earth, Planetary, and Space Sciences, University of California, Los Angeles, Los Angeles, California 90095, USA
| | - C T Russell
- Institute of Geophysics, Earth, Planetary, and Space Sciences, University of California, Los Angeles, Los Angeles, California 90095, USA
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6
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Dhillon RS, Rowin WA, Humphries RS, Kevin K, Ward JD, Phan TD, Nguyen LV, Wynne DD, Scott DA. Aerosolisation during tracheal intubation and extubation in an operating theatre setting. Anaesthesia 2020; 76:182-188. [PMID: 33047327 PMCID: PMC7675280 DOI: 10.1111/anae.15301] [Citation(s) in RCA: 44] [Impact Index Per Article: 11.0] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [Key Words] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Accepted: 09/29/2020] [Indexed: 01/25/2023]
Abstract
Aerosol‐generating procedures such as tracheal intubation and extubation pose a potential risk to healthcare workers because of the possibility of airborne transmission of infection. Detailed characterisation of aerosol quantities, particle size and generating activities has been undertaken in a number of simulations but not in actual clinical practice. The aim of this study was to determine whether the processes of facemask ventilation, tracheal intubation and extubation generate aerosols in clinical practice, and to characterise any aerosols produced. In this observational study, patients scheduled to undergo elective endonasal pituitary surgery without symptoms of COVID‐19 were recruited. Airway management including tracheal intubation and extubation was performed in a standard positive pressure operating room with aerosols detected using laser‐based particle image velocimetry to detect larger particles, and spectrometry with continuous air sampling to detect smaller particles. A total of 482,960 data points were assessed for complete procedures in three patients. Facemask ventilation, tracheal tube insertion and cuff inflation generated small particles 30–300 times above background noise that remained suspended in airflows and spread from the patient’s facial region throughout the confines of the operating theatre. Safe clinical practice of these procedures should reflect these particle profiles. This adds to data that inform decisions regarding the appropriate precautions to take in a real‐world setting.
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Affiliation(s)
- R S Dhillon
- Department of Neurosurgery, St Vincent's Hospital Melbourne, Fitzroy, Victoria, Australia
| | - W A Rowin
- Department of Mechanical Engineering, University of Melbourne, Parkville, Victoria, Australia
| | - R S Humphries
- Climate Science Centre, CSIRO Oceans and Atmosphere, Aspendale, Victoria, Australia
| | - K Kevin
- Department of Mechanical Engineering, University of Melbourne, Parkville, Victoria, Australia
| | - J D Ward
- Climate Science Centre, CSIRO Oceans and Atmosphere, Aspendale, Victoria, Australia
| | - T D Phan
- University of Melbourne and Department of Anaesthesia and Acute Pain Medicine, St Vincent's Hospital Melbourne, Fitzroy, Victoria, Australia
| | - L V Nguyen
- Department of Neurosurgery, St Vincent's Hospital Melbourne, Fitzroy, Victoria, Australia
| | - D D Wynne
- Department of Neurosurgery, St Vincent's Hospital Melbourne, Fitzroy, Victoria, Australia
| | - D A Scott
- University of Melbourne and Department of Anaesthesia and Acute Pain Medicine, St Vincent's Hospital Melbourne, Fitzroy, Victoria, Australia
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7
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Phan TD, Eastwood JP, Shay MA, Drake JF, Sonnerup BUÖ, Fujimoto M, Cassak PA, Øieroset M, Burch JL, Torbert RB, Rager AC, Dorelli JC, Gershman DJ, Pollock C, Pyakurel PS, Haggerty CC, Khotyaintsev Y, Lavraud B, Saito Y, Oka M, Ergun RE, Retino A, Le Contel O, Argall MR, Giles BL, Moore TE, Wilder FD, Strangeway RJ, Russell CT, Lindqvist PA, Magnes W. Publisher Correction: Electron magnetic reconnection without ion coupling in Earth's turbulent magnetosheath. Nature 2019; 569:E9. [PMID: 31073227 DOI: 10.1038/s41586-019-1208-1] [Citation(s) in RCA: 1] [Impact Index Per Article: 0.2] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/09/2022]
Abstract
Change history: In this Letter, the y-axis values in Fig. 3f should go from 4 to -8 (rather than from 4 to -4), the y-axis values in Fig. 3h should appear next to the major tick marks (rather than the minor ticks), and in Fig. 1b, the arrows at the top and bottom of the electron-scale current sheet were going in the wrong direction; these errors have been corrected online.
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Affiliation(s)
- T D Phan
- Space Sciences Laboratory, University of California, Berkeley, CA, USA.
| | - J P Eastwood
- The Blackett Laboratory, Imperial College London, London, UK
| | - M A Shay
- University of Delaware, Newark, DE, USA
| | - J F Drake
- University of Maryland, College Park, MD, USA
| | | | | | - P A Cassak
- West Virginia University, Morgantown, WV, USA
| | - M Øieroset
- Space Sciences Laboratory, University of California, Berkeley, CA, USA
| | - J L Burch
- Southwest Research Institute, San Antonio, TX, USA
| | - R B Torbert
- University of New Hampshire, Durham, NH, USA
| | - A C Rager
- Catholic University of America, Washington, DC, USA.,NASA Goddard Space Flight Center, Greenbelt, MD, USA
| | - J C Dorelli
- NASA Goddard Space Flight Center, Greenbelt, MD, USA
| | - D J Gershman
- NASA Goddard Space Flight Center, Greenbelt, MD, USA
| | | | | | | | | | - B Lavraud
- Institut de Recherche en Astrophysique et Planétologie, Université de Toulouse, Toulouse, France
| | - Y Saito
- ISAS/JAXA, Sagamihara, Japan
| | - M Oka
- Space Sciences Laboratory, University of California, Berkeley, CA, USA
| | - R E Ergun
- University of Colorado LASP, Boulder, CO, USA
| | - A Retino
- CNRS/Ecole Polytechnique, Paris, France
| | | | - M R Argall
- University of New Hampshire, Durham, NH, USA
| | - B L Giles
- NASA Goddard Space Flight Center, Greenbelt, MD, USA
| | - T E Moore
- NASA Goddard Space Flight Center, Greenbelt, MD, USA
| | - F D Wilder
- University of Colorado LASP, Boulder, CO, USA
| | - R J Strangeway
- University of California, Los Angeles, Los Angeles, CA, USA
| | - C T Russell
- University of California, Los Angeles, Los Angeles, CA, USA
| | | | - W Magnes
- Space Research Institute, Austrian Academy of Sciences, Graz, Austria
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8
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Angelopoulos V, Cruce P, Drozdov A, Grimes EW, Hatzigeorgiu N, King DA, Larson D, Lewis JW, McTiernan JM, Roberts DA, Russell CL, Hori T, Kasahara Y, Kumamoto A, Matsuoka A, Miyashita Y, Miyoshi Y, Shinohara I, Teramoto M, Faden JB, Halford AJ, McCarthy M, Millan RM, Sample JG, Smith DM, Woodger LA, Masson A, Narock AA, Asamura K, Chang TF, Chiang CY, Kazama Y, Keika K, Matsuda S, Segawa T, Seki K, Shoji M, Tam SWY, Umemura N, Wang BJ, Wang SY, Redmon R, Rodriguez JV, Singer HJ, Vandegriff J, Abe S, Nose M, Shinbori A, Tanaka YM, UeNo S, Andersson L, Dunn P, Fowler C, Halekas JS, Hara T, Harada Y, Lee CO, Lillis R, Mitchell DL, Argall MR, Bromund K, Burch JL, Cohen IJ, Galloy M, Giles B, Jaynes AN, Le Contel O, Oka M, Phan TD, Walsh BM, Westlake J, Wilder FD, Bale SD, Livi R, Pulupa M, Whittlesey P, DeWolfe A, Harter B, Lucas E, Auster U, Bonnell JW, Cully CM, Donovan E, Ergun RE, Frey HU, Jackel B, Keiling A, Korth H, McFadden JP, Nishimura Y, Plaschke F, Robert P, Turner DL, Weygand JM, Candey RM, Johnson RC, Kovalick T, Liu MH, McGuire RE, Breneman A, Kersten K, Schroeder P. The Space Physics Environment Data Analysis System (SPEDAS). Space Sci Rev 2019; 215:9. [PMID: 30880847 PMCID: PMC6380193 DOI: 10.1007/s11214-018-0576-4] [Citation(s) in RCA: 10] [Impact Index Per Article: 2.0] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [Key Words] [Grants] [Track Full Text] [Subscribe] [Scholar Register] [Received: 08/07/2018] [Accepted: 12/29/2018] [Indexed: 05/31/2023]
Abstract
With the advent of the Heliophysics/Geospace System Observatory (H/GSO), a complement of multi-spacecraft missions and ground-based observatories to study the space environment, data retrieval, analysis, and visualization of space physics data can be daunting. The Space Physics Environment Data Analysis System (SPEDAS), a grass-roots software development platform (www.spedas.org), is now officially supported by NASA Heliophysics as part of its data environment infrastructure. It serves more than a dozen space missions and ground observatories and can integrate the full complement of past and upcoming space physics missions with minimal resources, following clear, simple, and well-proven guidelines. Free, modular and configurable to the needs of individual missions, it works in both command-line (ideal for experienced users) and Graphical User Interface (GUI) mode (reducing the learning curve for first-time users). Both options have "crib-sheets," user-command sequences in ASCII format that can facilitate record-and-repeat actions, especially for complex operations and plotting. Crib-sheets enhance scientific interactions, as users can move rapidly and accurately from exchanges of technical information on data processing to efficient discussions regarding data interpretation and science. SPEDAS can readily query and ingest all International Solar Terrestrial Physics (ISTP)-compatible products from the Space Physics Data Facility (SPDF), enabling access to a vast collection of historic and current mission data. The planned incorporation of Heliophysics Application Programmer's Interface (HAPI) standards will facilitate data ingestion from distributed datasets that adhere to these standards. Although SPEDAS is currently Interactive Data Language (IDL)-based (and interfaces to Java-based tools such as Autoplot), efforts are under-way to expand it further to work with python (first as an interface tool and potentially even receiving an under-the-hood replacement). We review the SPEDAS development history, goals, and current implementation. We explain its "modes of use" with examples geared for users and outline its technical implementation and requirements with software developers in mind. We also describe SPEDAS personnel and software management, interfaces with other organizations, resources and support structure available to the community, and future development plans. ELECTRONIC SUPPLEMENTARY MATERIAL The online version of this article (10.1007/s11214-018-0576-4) contains supplementary material, which is available to authorized users.
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Affiliation(s)
- V. Angelopoulos
- Department of Earth, Planetary and Space Sciences, and Institute of Geophysics and Planetary Physics, University of California, Los Angeles, USA
| | - P. Cruce
- Department of Earth, Planetary and Space Sciences, and Institute of Geophysics and Planetary Physics, University of California, Los Angeles, USA
| | - A. Drozdov
- Department of Earth, Planetary and Space Sciences, and Institute of Geophysics and Planetary Physics, University of California, Los Angeles, USA
| | - E. W. Grimes
- Department of Earth, Planetary and Space Sciences, and Institute of Geophysics and Planetary Physics, University of California, Los Angeles, USA
| | - N. Hatzigeorgiu
- Space Sciences Laboratory, University of California, Berkeley, USA
| | - D. A. King
- Space Sciences Laboratory, University of California, Berkeley, USA
| | - D. Larson
- Space Sciences Laboratory, University of California, Berkeley, USA
| | - J. W. Lewis
- Space Sciences Laboratory, University of California, Berkeley, USA
| | - J. M. McTiernan
- Space Sciences Laboratory, University of California, Berkeley, USA
| | | | - C. L. Russell
- Department of Earth, Planetary and Space Sciences, and Institute of Geophysics and Planetary Physics, University of California, Los Angeles, USA
| | - T. Hori
- Institute for Space-Earth Environmental Research, Nagoya University, Nagoya, Japan
| | | | - A. Kumamoto
- Tohoku University, 6-3, Aoba, Aramaki, Aoba Sendai, 980-8578 Japan
| | - A. Matsuoka
- Institute of Space and Astronautical Science, Japan Aerospace Exploration Agency, Sagamihara, Japan
| | - Y. Miyashita
- Korea Astronomy and Space Science Institute, Daejeon, South Korea
| | - Y. Miyoshi
- Institute for Space-Earth Environmental Research, Nagoya University, Nagoya, Japan
| | - I. Shinohara
- Institute of Space and Astronautical Science, Japan Aerospace Exploration Agency, Sagamihara, Japan
| | - M. Teramoto
- Institute for Space-Earth Environmental Research, Nagoya University, Nagoya, Japan
| | | | - A. J. Halford
- Space Sciences Department, The Aerospace Corporation, Chantilly, VA USA
| | - M. McCarthy
- Department of Earth and Space Sciences, University of Washington, Seattle, WA USA
| | - R. M. Millan
- Department of Physics and Astronomy, Dartmouth College, Hanover, NH USA
| | - J. G. Sample
- Department of Physics, Montana State University, Bozeman, MT USA
| | - D. M. Smith
- Santa Cruz Institute of Particle Physics and Department of Physics, University of California, Santa Cruz, CA 95064 USA
| | - L. A. Woodger
- Department of Physics and Astronomy, Dartmouth College, Hanover, NH USA
| | - A. Masson
- European Space Agency, ESAC, SCI-OPD, Madrid, Spain
| | - A. A. Narock
- ADNET Systems Inc., NASA Goddard Space Flight Center, Greenbelt, MD USA
| | - K. Asamura
- Institute of Space and Astronautical Science, Japan Aerospace Exploration Agency, Sagamihara, Japan
| | - T. F. Chang
- Institute for Space-Earth Environmental Research, Nagoya University, Nagoya, Japan
| | - C.-Y. Chiang
- Institute of Space and Plasma Sciences, National Cheng Kung University, Tainan, Taiwan
| | - Y. Kazama
- Academia Sinica Institute of Astronomy and Astrophysics, Taipei, Taiwan
| | - K. Keika
- Department of Earth and Planetary Science, Graduate School of Science, University of Tokyo, Tokyo, Japan
| | - S. Matsuda
- Institute for Space-Earth Environmental Research, Nagoya University, Nagoya, Japan
| | - T. Segawa
- Institute for Space-Earth Environmental Research, Nagoya University, Nagoya, Japan
| | - K. Seki
- Department of Earth and Planetary Science, Graduate School of Science, University of Tokyo, Tokyo, Japan
| | - M. Shoji
- Institute for Space-Earth Environmental Research, Nagoya University, Nagoya, Japan
| | - S. W. Y. Tam
- Institute of Space and Plasma Sciences, National Cheng Kung University, Tainan, Taiwan
| | - N. Umemura
- Institute for Space-Earth Environmental Research, Nagoya University, Nagoya, Japan
| | - B.-J. Wang
- Academia Sinica Institute of Astronomy and Astrophysics, Taipei, Taiwan
- Graduate Institute of Space Science, National Central University, Taoyuan, Taiwan
| | - S.-Y. Wang
- Academia Sinica Institute of Astronomy and Astrophysics, Taipei, Taiwan
| | - R. Redmon
- National Centers for Environmental Information, National Oceanic and Atmospheric Administration, Boulder, CO USA
| | - J. V. Rodriguez
- National Centers for Environmental Information, National Oceanic and Atmospheric Administration, Boulder, CO USA
- Cooperative Institute for Research in Environmental Sciences (CIRES) at University of Colorado at Boulder, Boulder, CO USA
| | - H. J. Singer
- Space Weather Prediction Center, National Oceanic and Atmospheric Administration, Boulder, CO USA
| | - J. Vandegriff
- The Johns Hopkins University Applied Physics Laboratory, Laurel, MD USA
| | - S. Abe
- International Center for Space Weather Science and Education, Kyushu University, Fukuoka, Japan
| | - M. Nose
- Institute for Space-Earth Environmental Research, Nagoya University, Nagoya, Japan
- World Data Center for Geomagnetism, Kyoto Data Analysis Center for Geomagnetism and Space Magnetism, Kyoto University, Kyoto, Japan
| | - A. Shinbori
- Institute for Space-Earth Environmental Research, Nagoya University, Nagoya, Japan
| | - Y.-M. Tanaka
- National Institute of Polar Research, Tokyo, Japan
| | - S. UeNo
- Hida Observatory, Kyoto University, Kyoto, Japan
| | - L. Andersson
- Laboratory for Atmospheric and Space Physics, University of Colorado, Boulder, CO USA
| | - P. Dunn
- Space Sciences Laboratory, University of California, Berkeley, USA
| | - C. Fowler
- Laboratory for Atmospheric and Space Physics, University of Colorado, Boulder, CO USA
| | - J. S. Halekas
- Department of Physics and Astronomy, University of Iowa, Iowa City, IA USA
| | - T. Hara
- Space Sciences Laboratory, University of California, Berkeley, USA
| | - Y. Harada
- Department of Geophysics, Kyoto University, Kyoto, Japan
| | - C. O. Lee
- Space Sciences Laboratory, University of California, Berkeley, USA
| | - R. Lillis
- Space Sciences Laboratory, University of California, Berkeley, USA
| | - D. L. Mitchell
- Space Sciences Laboratory, University of California, Berkeley, USA
| | - M. R. Argall
- Physics Department and Space Science Center, University of New Hampshire, Durham, NH USA
| | - K. Bromund
- NASA Goddard Space Flight Center, Greenbelt, MD USA
| | - J. L. Burch
- Southwest Research Institute, San Antonio, TX USA
| | - I. J. Cohen
- The Johns Hopkins University Applied Physics Laboratory, Laurel, MD USA
| | - M. Galloy
- National Center for Atmospheric Research, Boulder, CO USA
| | - B. Giles
- NASA Goddard Space Flight Center, Greenbelt, MD USA
| | - A. N. Jaynes
- Department of Physics and Astronomy, University of Iowa, Iowa City, IA USA
| | - O. Le Contel
- Laboratoire de Physique des Plasmas, CNRS/Ecole Polytechnique/Sorbonne Université/Univ. Paris Sud/Observatoire de Paris, Paris, France
| | - M. Oka
- Space Sciences Laboratory, University of California, Berkeley, USA
| | - T. D. Phan
- Space Sciences Laboratory, University of California, Berkeley, USA
| | - B. M. Walsh
- Center for Space Physics, Department of Mechanical Engineering, Boston University, Boston, MA USA
| | - J. Westlake
- The Johns Hopkins University Applied Physics Laboratory, Laurel, MD USA
| | - F. D. Wilder
- Laboratory for Atmospheric and Space Physics, University of Colorado, Boulder, CO USA
| | - S. D. Bale
- Space Sciences Laboratory, University of California, Berkeley, USA
| | - R. Livi
- Space Sciences Laboratory, University of California, Berkeley, USA
| | - M. Pulupa
- Space Sciences Laboratory, University of California, Berkeley, USA
| | - P. Whittlesey
- Space Sciences Laboratory, University of California, Berkeley, USA
| | - A. DeWolfe
- Laboratory for Atmospheric and Space Physics, University of Colorado, Boulder, CO USA
| | - B. Harter
- Laboratory for Atmospheric and Space Physics, University of Colorado, Boulder, CO USA
| | - E. Lucas
- Laboratory for Atmospheric and Space Physics, University of Colorado, Boulder, CO USA
| | - U. Auster
- Institute for Geophysics and Extraterrestrial Physics, Technical University of Braunschweig, Braunschweig, Germany
| | - J. W. Bonnell
- Space Sciences Laboratory, University of California, Berkeley, USA
| | - C. M. Cully
- University of Calgary, Calgary, Ontario Canada
| | - E. Donovan
- University of Calgary, Calgary, Ontario Canada
| | - R. E. Ergun
- Laboratory for Atmospheric and Space Physics, University of Colorado, Boulder, CO USA
| | - H. U. Frey
- Space Sciences Laboratory, University of California, Berkeley, USA
| | - B. Jackel
- University of Calgary, Calgary, Ontario Canada
| | - A. Keiling
- Space Sciences Laboratory, University of California, Berkeley, USA
| | - H. Korth
- The Johns Hopkins University Applied Physics Laboratory, Laurel, MD USA
| | - J. P. McFadden
- Space Sciences Laboratory, University of California, Berkeley, USA
| | - Y. Nishimura
- Center for Space Physics and Department of Electrical and Computer Engineering, Boston University, Boston, MA USA
| | - F. Plaschke
- Space Research Institute, Austrian Academy of Sciences, Institute of Physics, University of Graz, Graz, Austria
| | - P. Robert
- Laboratoire de Physique des Plasmas, CNRS/Ecole Polytechnique/Sorbonne Université/Univ. Paris Sud/Observatoire de Paris, Paris, France
| | | | - J. M. Weygand
- Department of Earth, Planetary and Space Sciences, and Institute of Geophysics and Planetary Physics, University of California, Los Angeles, USA
| | - R. M. Candey
- NASA Goddard Space Flight Center, Greenbelt, MD USA
| | - R. C. Johnson
- ADNET Systems Inc., NASA Goddard Space Flight Center, Greenbelt, MD USA
| | - T. Kovalick
- ADNET Systems Inc., NASA Goddard Space Flight Center, Greenbelt, MD USA
| | - M. H. Liu
- ADNET Systems Inc., NASA Goddard Space Flight Center, Greenbelt, MD USA
| | | | - A. Breneman
- University of Minnesota, Minneapolis, MN USA
| | - K. Kersten
- University of Minnesota, Minneapolis, MN USA
| | - P. Schroeder
- Space Sciences Laboratory, University of California, Berkeley, USA
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9
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Torbert RB, Burch JL, Phan TD, Hesse M, Argall MR, Shuster J, Ergun RE, Alm L, Nakamura R, Genestreti KJ, Gershman DJ, Paterson WR, Turner DL, Cohen I, Giles BL, Pollock CJ, Wang S, Chen LJ, Stawarz JE, Eastwood JP, Hwang KJ, Farrugia C, Dors I, Vaith H, Mouikis C, Ardakani A, Mauk BH, Fuselier SA, Russell CT, Strangeway RJ, Moore TE, Drake JF, Shay MA, Khotyaintsev YV, Lindqvist PA, Baumjohann W, Wilder FD, Ahmadi N, Dorelli JC, Avanov LA, Oka M, Baker DN, Fennell JF, Blake JB, Jaynes AN, Le Contel O, Petrinec SM, Lavraud B, Saito Y. Electron-scale dynamics of the diffusion region during symmetric magnetic reconnection in space. Science 2018; 362:1391-1395. [PMID: 30442767 DOI: 10.1126/science.aat2998] [Citation(s) in RCA: 158] [Impact Index Per Article: 26.3] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 02/12/2018] [Accepted: 11/06/2018] [Indexed: 11/02/2022]
Abstract
Magnetic reconnection is an energy conversion process that occurs in many astrophysical contexts including Earth's magnetosphere, where the process can be investigated in situ by spacecraft. On 11 July 2017, the four Magnetospheric Multiscale spacecraft encountered a reconnection site in Earth's magnetotail, where reconnection involves symmetric inflow conditions. The electron-scale plasma measurements revealed (i) super-Alfvénic electron jets reaching 15,000 kilometers per second; (ii) electron meandering motion and acceleration by the electric field, producing multiple crescent-shaped structures in the velocity distributions; and (iii) the spatial dimensions of the electron diffusion region with an aspect ratio of 0.1 to 0.2, consistent with fast reconnection. The well-structured multiple layers of electron populations indicate that the dominant electron dynamics are mostly laminar, despite the presence of turbulence near the reconnection site.
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Affiliation(s)
- R B Torbert
- University of New Hampshire, Durham, NH, USA. .,Southwest Research Institute (SwRI), San Antonio, TX, USA
| | - J L Burch
- Southwest Research Institute (SwRI), San Antonio, TX, USA
| | - T D Phan
- University of California, Berkeley, CA, USA
| | - M Hesse
- Southwest Research Institute (SwRI), San Antonio, TX, USA.,University of Bergen, Bergen, Norway
| | - M R Argall
- University of New Hampshire, Durham, NH, USA
| | - J Shuster
- NASA Goddard Space Flight Center, Greenbelt, MD, USA
| | - R E Ergun
- University of Colorado Laboratory for Atmospheric and Space Physics, Boulder, CO, USA
| | - L Alm
- Swedish Institute of Space Physics, Uppsala, Sweden
| | - R Nakamura
- Space Research Institute, Austrian Academy of Sciences, Graz, Austria
| | - K J Genestreti
- Space Research Institute, Austrian Academy of Sciences, Graz, Austria
| | - D J Gershman
- NASA Goddard Space Flight Center, Greenbelt, MD, USA
| | - W R Paterson
- NASA Goddard Space Flight Center, Greenbelt, MD, USA
| | - D L Turner
- Aerospace Corporation, El Segundo, CA, USA
| | - I Cohen
- Johns Hopkins University Applied Physics Laboratory, Laurel, MD, USA
| | - B L Giles
- NASA Goddard Space Flight Center, Greenbelt, MD, USA
| | - C J Pollock
- NASA Goddard Space Flight Center, Greenbelt, MD, USA
| | - S Wang
- University of Maryland, College Park, MD, USA
| | - L-J Chen
- NASA Goddard Space Flight Center, Greenbelt, MD, USA.,University of Maryland, College Park, MD, USA
| | - J E Stawarz
- Blackett Laboratory, Imperial College London, London, UK
| | - J P Eastwood
- Blackett Laboratory, Imperial College London, London, UK
| | - K J Hwang
- Southwest Research Institute (SwRI), San Antonio, TX, USA
| | - C Farrugia
- University of New Hampshire, Durham, NH, USA
| | - I Dors
- University of New Hampshire, Durham, NH, USA
| | - H Vaith
- University of New Hampshire, Durham, NH, USA
| | - C Mouikis
- University of New Hampshire, Durham, NH, USA
| | - A Ardakani
- University of New Hampshire, Durham, NH, USA
| | - B H Mauk
- Johns Hopkins University Applied Physics Laboratory, Laurel, MD, USA
| | - S A Fuselier
- Southwest Research Institute (SwRI), San Antonio, TX, USA.,University of Texas, San Antonio, TX, USA
| | - C T Russell
- University of California, Los Angeles, CA, USA
| | | | - T E Moore
- NASA Goddard Space Flight Center, Greenbelt, MD, USA
| | - J F Drake
- University of Maryland, College Park, MD, USA
| | - M A Shay
- University of Delaware, Newark, DE, USA
| | | | | | - W Baumjohann
- Space Research Institute, Austrian Academy of Sciences, Graz, Austria
| | - F D Wilder
- University of Colorado Laboratory for Atmospheric and Space Physics, Boulder, CO, USA
| | - N Ahmadi
- University of Colorado Laboratory for Atmospheric and Space Physics, Boulder, CO, USA
| | - J C Dorelli
- NASA Goddard Space Flight Center, Greenbelt, MD, USA
| | - L A Avanov
- NASA Goddard Space Flight Center, Greenbelt, MD, USA
| | - M Oka
- University of California, Berkeley, CA, USA
| | - D N Baker
- University of Colorado Laboratory for Atmospheric and Space Physics, Boulder, CO, USA
| | | | - J B Blake
- Aerospace Corporation, El Segundo, CA, USA
| | | | - O Le Contel
- Laboratoire de Physique des Plasmas, CNRS/Ecole Polytechnique/Sorbonne Université/Univ. Paris Sud/Observatoire de Paris, Paris, France
| | - S M Petrinec
- Lockheed Martin Advanced Technology Center, Palo Alto, CA, USA
| | - B Lavraud
- Institut de Recherche en Astrophysique et Planétologie, CNRS, Centre National d'Etudes Spatiales, Université de Toulouse, Toulouse, France
| | - Y Saito
- Institute for Space and Astronautical Sciences, Sagamihara, Japan
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10
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Eastwood JP, Mistry R, Phan TD, Schwartz SJ, Ergun RE, Drake JF, Øieroset M, Stawarz JE, Goldman MV, Haggerty C, Shay MA, Burch JL, Gershman DJ, Giles BL, Lindqvist PA, Torbert RB, Strangeway RJ, Russell CT. Guide Field Reconnection: Exhaust Structure and Heating. Geophys Res Lett 2018; 45:4569-4577. [PMID: 31031447 PMCID: PMC6473590 DOI: 10.1029/2018gl077670] [Citation(s) in RCA: 1] [Impact Index Per Article: 0.2] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [Key Words] [Track Full Text] [Subscribe] [Scholar Register] [Received: 02/23/2018] [Revised: 04/11/2018] [Accepted: 04/14/2018] [Indexed: 06/09/2023]
Abstract
Magnetospheric Multiscale observations are used to probe the structure and temperature profile of a guide field reconnection exhaust ~100 ion inertial lengths downstream from the X-line in the Earth's magnetosheath. Asymmetric Hall electric and magnetic field signatures were detected, together with a density cavity confined near 1 edge of the exhaust and containing electron flow toward the X-line. Electron holes were also detected both on the cavity edge and at the Hall magnetic field reversal. Predominantly parallel ion and electron heating was observed in the main exhaust, but within the cavity, electron cooling and enhanced parallel ion heating were found. This is explained in terms of the parallel electric field, which inhibits electron mixing within the cavity on newly reconnected field lines but accelerates ions. Consequently, guide field reconnection causes inhomogeneous changes in ion and electron temperature across the exhaust.
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Affiliation(s)
| | - R. Mistry
- The Blackett LaboratoryImperial College LondonLondonUK
| | - T. D. Phan
- Space Sciences LaboratoryUniversity of CaliforniaBerkeleyCAUSA
| | - S. J. Schwartz
- The Blackett LaboratoryImperial College LondonLondonUK
- LASP/Department of Astrophysical and Planetary SciencesUniversity of Colorado BoulderBoulderCOUSA
| | - R. E. Ergun
- LASP/Department of Astrophysical and Planetary SciencesUniversity of Colorado BoulderBoulderCOUSA
| | - J. F. Drake
- Department of Physics and Institute for Physical Science and TechnologyUniversity of MarylandCollege ParkMDUSA
| | - M. Øieroset
- Space Sciences LaboratoryUniversity of CaliforniaBerkeleyCAUSA
| | - J. E. Stawarz
- The Blackett LaboratoryImperial College LondonLondonUK
| | - M. V. Goldman
- Department of PhysicsUniversity of Colorado BoulderBoulderCOUSA
| | - C. Haggerty
- Department of Physics and AstronomyUniversity of DelawareNewarkDEUSA
- Now at The Department of Astronomy and AstrophysicsUniversity of ChicagoChicagoILUSA
| | - M. A. Shay
- Department of Physics and AstronomyUniversity of DelawareNewarkDEUSA
| | - J. L. Burch
- Southwest Research InstituteSan AntonioTXUSA
| | - D. J. Gershman
- Department of Physics and AstronomyUniversity of DelawareNewarkDEUSA
- NASA Goddard Space Flight CenterGreenbeltMDUSA
| | - B. L. Giles
- NASA Goddard Space Flight CenterGreenbeltMDUSA
| | - P. A. Lindqvist
- Department of Space and Plasma PhysicsRoyal Institute of TechnologyStockholmSweden
| | - R. B. Torbert
- Now at The Department of Astronomy and AstrophysicsUniversity of ChicagoChicagoILUSA
- Space Science CenterUniversity of New HampshireDurhamNHUSA
| | - R. J. Strangeway
- Department of Earth, Planetary, and Space SciencesUniversity of CaliforniaLos AngelesCAUSA
| | - C. T. Russell
- Department of Earth, Planetary, and Space SciencesUniversity of CaliforniaLos AngelesCAUSA
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11
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Burch JL, Webster JM, Genestreti KJ, Torbert RB, Giles BL, Fuselier SA, Dorelli JC, Rager AC, Phan TD, Allen RC, Chen L, Wang S, Le Contel O, Russell CT, Strangeway RJ, Ergun RE, Jaynes AN, Lindqvist P, Graham DB, Wilder FD, Hwang K, Goldstein J. Wave Phenomena and Beam-Plasma Interactions at the Magnetopause Reconnection Region. J Geophys Res Space Phys 2018; 123:1118-1133. [PMID: 29938153 PMCID: PMC5993346 DOI: 10.1002/2017ja024789] [Citation(s) in RCA: 1] [Impact Index Per Article: 0.2] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Figures] [Subscribe] [Scholar Register] [Received: 09/22/2017] [Revised: 12/28/2017] [Accepted: 01/10/2018] [Indexed: 06/08/2023]
Abstract
This paper reports on Magnetospheric Multiscale observations of whistler mode chorus and higher-frequency electrostatic waves near and within a reconnection diffusion region on 23 November 2016. The diffusion region is bounded by crescent-shaped electron distributions and associated dissipation just upstream of the X-line and by magnetic field-aligned currents and electric fields leading to dissipation near the electron stagnation point. Measurements were made southward of the X-line as determined by southward directed ion and electron jets. We show that electrostatic wave generation is due to magnetosheath electron beams formed by the electron jets as they interact with a cold background plasma and more energetic population of magnetospheric electrons. On the magnetosphere side of the X-line the electron beams are accompanied by a strong perpendicular electron temperature anisotropy, which is shown to be the source of an observed rising-tone whistler mode chorus event. We show that the apex of the chorus event and the onset of electrostatic waves coincide with the opening of magnetic field lines at the electron stagnation point.
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Affiliation(s)
- J. L. Burch
- Southwest Research InstituteSan AntonioTXUSA
| | - J. M. Webster
- Department of Physics and AstronomyRice UniversityHoustonTXUSA
| | | | - R. B. Torbert
- Southwest Research InstituteSan AntonioTXUSA
- Department of PhysicsUniversity of New HampshireDurhamNHUSA
| | - B. L. Giles
- NASA, Goddard Space Flight CenterGreenbeltMDUSA
| | | | | | - A. C. Rager
- NASA, Goddard Space Flight CenterGreenbeltMDUSA
- Department of PhysicsCatholic University of AmericaWashingtonDCUSA
| | - T. D. Phan
- Space Sciences LaboratoryUniversity of CaliforniaBerkeleyCAUSA
| | - R. C. Allen
- Applied Physics LaboratoryThe Johns Hopkins UniversityLaurelMDUSA
| | - L.‐J. Chen
- Department of AstronomyUniversity of MarylandCollege ParkMDUSA
| | - S. Wang
- Department of AstronomyUniversity of MarylandCollege ParkMDUSA
| | - O. Le Contel
- Laboratoire de Physique des PlasmasCNRS, Ecole Polytechnique, UPMC University Paris 06, Université Paris‐Sud, Observatoire de ParisParisFrance
| | - C. T. Russell
- Earth and Planetary SciencesUniversity of CaliforniaLos AngelesCAUSA
| | - R. J. Strangeway
- Earth and Planetary SciencesUniversity of CaliforniaLos AngelesCAUSA
| | - R. E. Ergun
- LASPUniversity of Colorado BoulderBoulderCOUSA
| | - A. N. Jaynes
- Department of Physics and AstronomyUniversity of IowaIowa CityIAUSA
| | | | | | | | - K.‐J. Hwang
- Southwest Research InstituteSan AntonioTXUSA
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12
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Servidio S, Chasapis A, Matthaeus WH, Perrone D, Valentini F, Parashar TN, Veltri P, Gershman D, Russell CT, Giles B, Fuselier SA, Phan TD, Burch J. Magnetospheric Multiscale Observation of Plasma Velocity-Space Cascade: Hermite Representation and Theory. Phys Rev Lett 2017; 119:205101. [PMID: 29219385 DOI: 10.1103/physrevlett.119.205101] [Citation(s) in RCA: 7] [Impact Index Per Article: 1.0] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [Track Full Text] [Subscribe] [Scholar Register] [Received: 06/12/2017] [Indexed: 06/07/2023]
Abstract
Plasma turbulence is investigated using unprecedented high-resolution ion velocity distribution measurements by the Magnetospheric Multiscale mission (MMS) in the Earth's magnetosheath. This novel observation of a highly structured particle distribution suggests a cascadelike process in velocity space. Complex velocity space structure is investigated using a three-dimensional Hermite transform, revealing, for the first time in observational data, a power-law distribution of moments. In analogy to hydrodynamics, a Kolmogorov approach leads directly to a range of predictions for this phase-space transport. The scaling theory is found to be in agreement with observations. The combined use of state-of-the-art MMS data sets, novel implementation of a Hermite transform method, and scaling theory of the velocity cascade opens new pathways to the understanding of plasma turbulence and the crucial velocity space features that lead to dissipation in plasmas.
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Affiliation(s)
- S Servidio
- Dipartimento di Fisica, Università della Calabria, I-87036 Cosenza, Italy
| | - A Chasapis
- Bartol Research Institute and Department of Physics and Astronomy, University of Delaware, Newark, Delaware 19716, USA
| | - W H Matthaeus
- Bartol Research Institute and Department of Physics and Astronomy, University of Delaware, Newark, Delaware 19716, USA
| | - D Perrone
- European Space Agency, ESAC, 28692 Madrid, Spain
| | - F Valentini
- Dipartimento di Fisica, Università della Calabria, I-87036 Cosenza, Italy
| | - T N Parashar
- Bartol Research Institute and Department of Physics and Astronomy, University of Delaware, Newark, Delaware 19716, USA
| | - P Veltri
- Dipartimento di Fisica, Università della Calabria, I-87036 Cosenza, Italy
| | - D Gershman
- NASA Goddard Space Flight Center, Greenbelt, Maryland 20771, USA
| | - C T Russell
- University of California at Los Angeles, Los Angeles, California 90095, USA
| | - B Giles
- NASA Goddard Space Flight Center, Greenbelt, Maryland 20771, USA
| | - S A Fuselier
- Southwest Research Institute, San Antonio, Texas 78238, USA
- University of Texas at San Antonio, San Antonio, Texas 78249, USA
| | - T D Phan
- University of California, Berkeley, California 94720, USA
| | - J Burch
- Southwest Research Institute, San Antonio, Texas 78238, USA
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13
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Wilder FD, Ergun RE, Eriksson S, Phan TD, Burch JL, Ahmadi N, Goodrich KA, Newman DL, Trattner KJ, Torbert RB, Giles BL, Strangeway RJ, Magnes W, Lindqvist PA, Khotyaintsev YV. Multipoint Measurements of the Electron Jet of Symmetric Magnetic Reconnection with a Moderate Guide Field. Phys Rev Lett 2017; 118:265101. [PMID: 28707935 DOI: 10.1103/physrevlett.118.265101] [Citation(s) in RCA: 4] [Impact Index Per Article: 0.6] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [Track Full Text] [Subscribe] [Scholar Register] [Received: 04/04/2017] [Indexed: 06/07/2023]
Abstract
We report observations from the Magnetospheric Multiscale (MMS) satellites of the electron jet in a symmetric magnetic reconnection event with moderate guide field. All four spacecraft sampled the ion diffusion region and observed the electron exhaust. The observations suggest that the presence of the guide field leads to an asymmetric Hall field, which results in an electron jet skewed towards the separatrix with a nonzero component along the magnetic field. The jet appears in conjunction with a spatially and temporally persistent parallel electric field ranging from -3 to -5 mV/m, which led to dissipation on the order of 8 nW/m^{3}. The parallel electric field heats electrons that drift through it, and is associated with a streaming instability and electron phase space holes.
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Affiliation(s)
- F D Wilder
- Laboratory of Atmospheric and Space Sciences, University of Colorado, Boulder, Colorado 80303, USA
| | - R E Ergun
- Laboratory of Atmospheric and Space Sciences, University of Colorado, Boulder, Colorado 80303, USA
- Department of Astrophysical and Planetary Sciences, University of Colorado, Boulder, Colorado 80303, USA
| | - S Eriksson
- Laboratory of Atmospheric and Space Sciences, University of Colorado, Boulder, Colorado 80303, USA
| | - T D Phan
- Space Sciences Laboratory, University of California, Berkeley, California 94720, USA
| | - J L Burch
- Southwest Research Institute, San Antonio, Texas 78238, USA
| | - N Ahmadi
- Laboratory of Atmospheric and Space Sciences, University of Colorado, Boulder, Colorado 80303, USA
| | - K A Goodrich
- Laboratory of Atmospheric and Space Sciences, University of Colorado, Boulder, Colorado 80303, USA
- Department of Astrophysical and Planetary Sciences, University of Colorado, Boulder, Colorado 80303, USA
| | - D L Newman
- Department of Physics, University of Colorado, Boulder, Colorado 80303, USA
| | - K J Trattner
- Laboratory of Atmospheric and Space Sciences, University of Colorado, Boulder, Colorado 80303, USA
| | - R B Torbert
- Department of Physics, University of New Hampshire, Durham, New Hampshire 03824, USA
| | - B L Giles
- NASA Goddard Space Flight Center, Greenbelt, Maryland 20771, USA
| | - R J Strangeway
- Department of Earth and Space Sciences, University of California Los Angeles, Los Angeles, California 90095, USA
| | - W Magnes
- Space Research Institute, Austrian Academy of Sciences, Graz 8042, Austria
| | - P-A Lindqvist
- Royal Institute of Technology, Stockholm SE-11428, Sweden
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14
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Mistry R, Eastwood JP, Haggerty CC, Shay MA, Phan TD, Hietala H, Cassak PA. Observations of Hall Reconnection Physics Far Downstream of the X Line. Phys Rev Lett 2016; 117:185102. [PMID: 27835012 DOI: 10.1103/physrevlett.117.185102] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [Track Full Text] [Subscribe] [Scholar Register] [Received: 04/27/2016] [Indexed: 06/06/2023]
Abstract
Observations made using the Wind spacecraft of Hall magnetic fields in solar wind reconnection exhausts are presented. These observations are consistent with the generation of Hall fields by a narrow ion inertial scale current layer near the separatrix, which is confirmed with an appropriately scaled particle-in-cell simulation that shows excellent agreement with observations. The Hall fields are observed thousands of ion inertial lengths downstream from the reconnection X line, indicating that narrow regions of kinetic dynamics can persist extremely far downstream.
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Affiliation(s)
- R Mistry
- The Blackett Laboratory, Imperial College London, London SW7 2AZ, United Kingdom
| | - J P Eastwood
- The Blackett Laboratory, Imperial College London, London SW7 2AZ, United Kingdom
| | - C C Haggerty
- Bartol Research Institute, Department of Physics and Astronomy, University of Delaware, Newark, Delaware 19716, USA
| | - M A Shay
- Bartol Research Institute, Department of Physics and Astronomy, University of Delaware, Newark, Delaware 19716, USA
| | - T D Phan
- Space Sciences Laboratory, University of California, Berkeley, California 94720, USA
| | - H Hietala
- Department of Earth, Planetary and Space Sciences, University of California, Los Angeles, California 90095, USA
| | - P A Cassak
- Department of Physics and Astronomy, West Virginia University, Morgantown, West Virginia 26506, USA
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15
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Uda Y, Phan TD, Kistler PM. Persistent left atrial thrombus on treatment with rivaroxaban and subsequent resolution after warfarin therapy. Intern Med J 2016; 46:855-6. [DOI: 10.1111/imj.13089] [Citation(s) in RCA: 3] [Impact Index Per Article: 0.4] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 09/29/2015] [Revised: 12/17/2015] [Accepted: 12/17/2015] [Indexed: 11/29/2022]
Affiliation(s)
- Y. Uda
- Department of Anaesthesia and Acute Pain Medicine; St Vincent's Hospital, The University of Melbourne; Melbourne Victoria Australia
| | - T. D. Phan
- Department of Anaesthesia and Acute Pain Medicine; St Vincent's Hospital, The University of Melbourne; Melbourne Victoria Australia
| | - P. M. Kistler
- Department of Cardiovascular Medicine; Alfred Hospital and Baker IDI Heart and Diabetes Institute; Melbourne Victoria Australia
- Cardiology Department, Faculty of Medicine, Dentistry, and Health Sciences; Royal Melbourne Hospital, The University of Melbourne; Melbourne Victoria Australia
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16
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Eriksson S, Wilder FD, Ergun RE, Schwartz SJ, Cassak PA, Burch JL, Chen LJ, Torbert RB, Phan TD, Lavraud B, Goodrich KA, Holmes JC, Stawarz JE, Sturner AP, Malaspina DM, Usanova ME, Trattner KJ, Strangeway RJ, Russell CT, Pollock CJ, Giles BL, Hesse M, Lindqvist PA, Drake JF, Shay MA, Nakamura R, Marklund GT. Magnetospheric Multiscale Observations of the Electron Diffusion Region of Large Guide Field Magnetic Reconnection. Phys Rev Lett 2016; 117:015001. [PMID: 27419573 DOI: 10.1103/physrevlett.117.015001] [Citation(s) in RCA: 4] [Impact Index Per Article: 0.5] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [Track Full Text] [Subscribe] [Scholar Register] [Received: 04/13/2016] [Indexed: 06/06/2023]
Abstract
We report observations from the Magnetospheric Multiscale (MMS) satellites of a large guide field magnetic reconnection event. The observations suggest that two of the four MMS spacecraft sampled the electron diffusion region, whereas the other two spacecraft detected the exhaust jet from the event. The guide magnetic field amplitude is approximately 4 times that of the reconnecting field. The event is accompanied by a significant parallel electric field (E_{∥}) that is larger than predicted by simulations. The high-speed (∼300 km/s) crossing of the electron diffusion region limited the data set to one complete electron distribution inside of the electron diffusion region, which shows significant parallel heating. The data suggest that E_{∥} is balanced by a combination of electron inertia and a parallel gradient of the gyrotropic electron pressure.
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Affiliation(s)
- S Eriksson
- Laboratory for Atmospheric and Space Physics, University of Colorado, Boulder, Colorado 80303, USA
| | - F D Wilder
- Laboratory for Atmospheric and Space Physics, University of Colorado, Boulder, Colorado 80303, USA
| | - R E Ergun
- Laboratory for Atmospheric and Space Physics, University of Colorado, Boulder, Colorado 80303, USA
- Department of Astrophysical and Planetary Sciences, University of Colorado, Boulder, Colorado 80303, USA
| | - S J Schwartz
- Laboratory for Atmospheric and Space Physics, University of Colorado, Boulder, Colorado 80303, USA
- The Blackett Laboratory, Imperial College, London SW7 2AZ, United Kingdom
| | - P A Cassak
- West Virginia University, Morgantown, West Virginia 26506, USA
| | - J L Burch
- Southwest Research Institute, San Antonio, Texas 78238-5166, USA
| | - L-J Chen
- University of Maryland, College Park, Maryland 20742, USA
| | - R B Torbert
- Southwest Research Institute, San Antonio, Texas 78238-5166, USA
- University of New Hampshire, Durham, New Hampshire 03824, USA
| | - T D Phan
- Space Sciences Laboratory, University of California, Berkeley, California 94720, USA
| | - B Lavraud
- Institut de Recherche en Astrophysique et Planétologie, Université de Toulouse, 31028 Toulouse, France
- Centre National de la Recherche Scientifique, UMR 5277, Toulouse, France
| | - K A Goodrich
- Laboratory for Atmospheric and Space Physics, University of Colorado, Boulder, Colorado 80303, USA
- Department of Astrophysical and Planetary Sciences, University of Colorado, Boulder, Colorado 80303, USA
| | - J C Holmes
- Laboratory for Atmospheric and Space Physics, University of Colorado, Boulder, Colorado 80303, USA
- Department of Astrophysical and Planetary Sciences, University of Colorado, Boulder, Colorado 80303, USA
| | - J E Stawarz
- Laboratory for Atmospheric and Space Physics, University of Colorado, Boulder, Colorado 80303, USA
- Department of Astrophysical and Planetary Sciences, University of Colorado, Boulder, Colorado 80303, USA
| | - A P Sturner
- Laboratory for Atmospheric and Space Physics, University of Colorado, Boulder, Colorado 80303, USA
- Department of Astrophysical and Planetary Sciences, University of Colorado, Boulder, Colorado 80303, USA
| | - D M Malaspina
- Laboratory for Atmospheric and Space Physics, University of Colorado, Boulder, Colorado 80303, USA
| | - M E Usanova
- Laboratory for Atmospheric and Space Physics, University of Colorado, Boulder, Colorado 80303, USA
| | - K J Trattner
- Laboratory for Atmospheric and Space Physics, University of Colorado, Boulder, Colorado 80303, USA
| | - R J Strangeway
- University of California, Los Angeles, Los Angeles, California 90095, USA
| | - C T Russell
- University of California, Los Angeles, Los Angeles, California 90095, USA
| | - C J Pollock
- NASA, Goddard Space Flight Center, Greenbelt, Maryland 20771, USA
| | - B L Giles
- NASA, Goddard Space Flight Center, Greenbelt, Maryland 20771, USA
| | - M Hesse
- NASA, Goddard Space Flight Center, Greenbelt, Maryland 20771, USA
| | - P-A Lindqvist
- KTH Royal Institute of Technology, SE-11428 Stockholm, Sweden
| | - J F Drake
- University of Maryland, College Park, Maryland 20742, USA
| | - M A Shay
- University of Delaware, Newark, Delaware 19716, USA
| | - R Nakamura
- Space Research Institute, Austrian Academy of Sciences, 8042 Graz, Austria
| | - G T Marklund
- KTH Royal Institute of Technology, SE-11428 Stockholm, Sweden
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17
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Ergun RE, Goodrich KA, Wilder FD, Holmes JC, Stawarz JE, Eriksson S, Sturner AP, Malaspina DM, Usanova ME, Torbert RB, Lindqvist PA, Khotyaintsev Y, Burch JL, Strangeway RJ, Russell CT, Pollock CJ, Giles BL, Hesse M, Chen LJ, Lapenta G, Goldman MV, Newman DL, Schwartz SJ, Eastwood JP, Phan TD, Mozer FS, Drake J, Shay MA, Cassak PA, Nakamura R, Marklund G. Magnetospheric Multiscale Satellites Observations of Parallel Electric Fields Associated with Magnetic Reconnection. Phys Rev Lett 2016; 116:235102. [PMID: 27341241 DOI: 10.1103/physrevlett.116.235102] [Citation(s) in RCA: 2] [Impact Index Per Article: 0.3] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [Track Full Text] [Subscribe] [Scholar Register] [Received: 03/23/2016] [Indexed: 06/06/2023]
Abstract
We report observations from the Magnetospheric Multiscale satellites of parallel electric fields (E_{∥}) associated with magnetic reconnection in the subsolar region of the Earth's magnetopause. E_{∥} events near the electron diffusion region have amplitudes on the order of 100 mV/m, which are significantly larger than those predicted for an antiparallel reconnection electric field. This Letter addresses specific types of E_{∥} events, which appear as large-amplitude, near unipolar spikes that are associated with tangled, reconnected magnetic fields. These E_{∥} events are primarily in or near a current layer near the separatrix and are interpreted to be double layers that may be responsible for secondary reconnection in tangled magnetic fields or flux ropes. These results are telling of the three-dimensional nature of magnetopause reconnection and indicate that magnetopause reconnection may be often patchy and/or drive turbulence along the separatrix that results in flux ropes and/or tangled magnetic fields.
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Affiliation(s)
- R E Ergun
- Department of Astrophysical and Planetary Sciences, University of Colorado, Boulder, Colorado 80303, USA
- Laboratory of Atmospheric and Space Sciences, University of Colorado, Boulder, Colorado 80303, USA
| | - K A Goodrich
- Department of Astrophysical and Planetary Sciences, University of Colorado, Boulder, Colorado 80303, USA
- Laboratory of Atmospheric and Space Sciences, University of Colorado, Boulder, Colorado 80303, USA
| | - F D Wilder
- Laboratory of Atmospheric and Space Sciences, University of Colorado, Boulder, Colorado 80303, USA
| | - J C Holmes
- Department of Astrophysical and Planetary Sciences, University of Colorado, Boulder, Colorado 80303, USA
- Laboratory of Atmospheric and Space Sciences, University of Colorado, Boulder, Colorado 80303, USA
| | - J E Stawarz
- Department of Astrophysical and Planetary Sciences, University of Colorado, Boulder, Colorado 80303, USA
- Laboratory of Atmospheric and Space Sciences, University of Colorado, Boulder, Colorado 80303, USA
| | - S Eriksson
- Laboratory of Atmospheric and Space Sciences, University of Colorado, Boulder, Colorado 80303, USA
| | - A P Sturner
- Department of Astrophysical and Planetary Sciences, University of Colorado, Boulder, Colorado 80303, USA
- Laboratory of Atmospheric and Space Sciences, University of Colorado, Boulder, Colorado 80303, USA
| | - D M Malaspina
- Department of Astrophysical and Planetary Sciences, University of Colorado, Boulder, Colorado 80303, USA
| | - M E Usanova
- Department of Astrophysical and Planetary Sciences, University of Colorado, Boulder, Colorado 80303, USA
| | - R B Torbert
- University of New Hampshire, Durham, New Hampshire 03824, USA
- Southwest Research Institute, San Antonio, Texas 78238, USA
| | - P-A Lindqvist
- KTH Royal Institute of Technology, Stockholm, Sweden
| | - Y Khotyaintsev
- Swedish Institute of Space Physics (Uppsala), Uppsala, Sweden
| | - J L Burch
- Southwest Research Institute, San Antonio, Texas 78238, USA
| | - R J Strangeway
- University of California, Los Angeles, Los Angeles, California 90095, USA
| | - C T Russell
- University of California, Los Angeles, Los Angeles, California 90095, USA
| | - C J Pollock
- NASA, Goddard Space Flight Center, Greenbelt, Maryland 20771, USA
| | - B L Giles
- NASA, Goddard Space Flight Center, Greenbelt, Maryland 20771, USA
| | - M Hesse
- NASA, Goddard Space Flight Center, Greenbelt, Maryland 20771, USA
| | - L J Chen
- University of Maryland, College Park, Maryland 20742, USA
| | - G Lapenta
- Leuven Universiteit, Leuven, Belgium
| | - M V Goldman
- Department of Physics, University of Colorado, Boulder, Colorado 80303, USA
| | - D L Newman
- Department of Physics, University of Colorado, Boulder, Colorado 80303, USA
| | - S J Schwartz
- Laboratory of Atmospheric and Space Sciences, University of Colorado, Boulder, Colorado 80303, USA
- The Blackett Laboratory, Imperial College London, United Kingdom
| | - J P Eastwood
- The Blackett Laboratory, Imperial College London, United Kingdom
| | - T D Phan
- Space Sciences Laboratory, University of California, Berkeley, California 94720, USA
| | - F S Mozer
- Space Sciences Laboratory, University of California, Berkeley, California 94720, USA
| | - J Drake
- University of Maryland, College Park, Maryland 20742, USA
| | - M A Shay
- University of Delaware, Newark, Delaware 19716, USA
| | - P A Cassak
- West Virginia University, Morgantown, West Virginia 26506, USA
| | - R Nakamura
- Space Research Institute, Austrian Academy of Sciences, Graz, Austria
| | - G Marklund
- KTH Royal Institute of Technology, Stockholm, Sweden
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18
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Eastwood JP, Phan TD, Cassak PA, Gershman DJ, Haggerty C, Malakit K, Shay MA, Mistry R, Øieroset M, Russell CT, Slavin JA, Argall MR, Avanov LA, Burch JL, Chen LJ, Dorelli JC, Ergun RE, Giles BL, Khotyaintsev Y, Lavraud B, Lindqvist PA, Moore TE, Nakamura R, Paterson W, Pollock C, Strangeway RJ, Torbert RB, Wang S. Ion-scale secondary flux ropes generated by magnetopause reconnection as resolved by MMS. Geophys Res Lett 2016; 43:4716-4724. [PMID: 27635105 PMCID: PMC5001194 DOI: 10.1002/2016gl068747] [Citation(s) in RCA: 2] [Impact Index Per Article: 0.3] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [Key Words] [Track Full Text] [Figures] [Subscribe] [Scholar Register] [Received: 03/21/2016] [Revised: 04/28/2016] [Accepted: 04/29/2016] [Indexed: 06/06/2023]
Abstract
New Magnetospheric Multiscale (MMS) observations of small-scale (~7 ion inertial length radius) flux transfer events (FTEs) at the dayside magnetopause are reported. The 10 km MMS tetrahedron size enables their structure and properties to be calculated using a variety of multispacecraft techniques, allowing them to be identified as flux ropes, whose flux content is small (~22 kWb). The current density, calculated using plasma and magnetic field measurements independently, is found to be filamentary. Intercomparison of the plasma moments with electric and magnetic field measurements reveals structured non-frozen-in ion behavior. The data are further compared with a particle-in-cell simulation. It is concluded that these small-scale flux ropes, which are not seen to be growing, represent a distinct class of FTE which is generated on the magnetopause by secondary reconnection.
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Affiliation(s)
| | - T. D. Phan
- Space Sciences LaboratoryUniversity of CaliforniaBerkeleyCaliforniaUSA
| | - P. A. Cassak
- Department of Physics and AstronomyWest Virginia UniversityMorgantownWest VirginiaUSA
| | - D. J. Gershman
- NASA Goddard Space Flight CenterGreenbeltMarylandUSA
- Department of AstronomyUniversity of MarylandCollege ParkMarylandUSA
| | - C. Haggerty
- Department of Physics and AstronomyUniversity of DelawareNewarkDelawareUSA
| | - K. Malakit
- Department of PhysicsMahidol UniversityBangkokThailand
| | - M. A. Shay
- Department of Physics and AstronomyUniversity of DelawareNewarkDelawareUSA
| | - R. Mistry
- Blackett LaboratoryImperial College LondonLondonUK
| | - M. Øieroset
- Space Sciences LaboratoryUniversity of CaliforniaBerkeleyCaliforniaUSA
| | - C. T. Russell
- Department of Earth, Planetary and Space SciencesUniversity of CaliforniaLos AngelesCaliforniaUSA
| | - J. A. Slavin
- Department of Climate and Space Sciences and EngineeringUniversity of MichiganAnn ArborMichiganUSA
| | - M. R. Argall
- Institute for the Study of Earth, Oceans and SpaceUniversity of New HampshireDurhamNew HampshireUSA
| | - L. A. Avanov
- NASA Goddard Space Flight CenterGreenbeltMarylandUSA
- Department of AstronomyUniversity of MarylandCollege ParkMarylandUSA
| | - J. L. Burch
- Southwest Research InstituteSan AntonioTexasUSA
| | - L. J. Chen
- NASA Goddard Space Flight CenterGreenbeltMarylandUSA
- Department of AstronomyUniversity of MarylandCollege ParkMarylandUSA
| | - J. C. Dorelli
- NASA Goddard Space Flight CenterGreenbeltMarylandUSA
| | - R. E. Ergun
- Laboratory for Atmospheric and Space PhysicsUniversity of Colorado BoulderBoulderColoradoUSA
| | - B. L. Giles
- NASA Goddard Space Flight CenterGreenbeltMarylandUSA
| | | | - B. Lavraud
- Institut de Recherche en Astrophysique et PlanétologieUniversité de ToulouseToulouseFrance
- Centre National de la Recherche Scientifique, UMR 5277ToulouseFrance
| | - P. A. Lindqvist
- School of Electrical EngineeringRoyal Institute of TechnologyStockholmSweden
| | - T. E. Moore
- NASA Goddard Space Flight CenterGreenbeltMarylandUSA
| | - R. Nakamura
- Space Research InstituteAustrian Academy of SciencesGrazAustria
| | - W. Paterson
- NASA Goddard Space Flight CenterGreenbeltMarylandUSA
| | | | - R. J. Strangeway
- Department of Earth, Planetary and Space SciencesUniversity of CaliforniaLos AngelesCaliforniaUSA
| | - R. B. Torbert
- Institute for the Study of Earth, Oceans and SpaceUniversity of New HampshireDurhamNew HampshireUSA
- Southwest Research InstituteSan AntonioTexasUSA
| | - S. Wang
- NASA Goddard Space Flight CenterGreenbeltMarylandUSA
- Department of AstronomyUniversity of MarylandCollege ParkMarylandUSA
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19
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Burch JL, Torbert RB, Phan TD, Chen LJ, Moore TE, Ergun RE, Eastwood JP, Gershman DJ, Cassak PA, Argall MR, Wang S, Hesse M, Pollock CJ, Giles BL, Nakamura R, Mauk BH, Fuselier SA, Russell CT, Strangeway RJ, Drake JF, Shay MA, Khotyaintsev YV, Lindqvist PA, Marklund G, Wilder FD, Young DT, Torkar K, Goldstein J, Dorelli JC, Avanov LA, Oka M, Baker DN, Jaynes AN, Goodrich KA, Cohen IJ, Turner DL, Fennell JF, Blake JB, Clemmons J, Goldman M, Newman D, Petrinec SM, Trattner KJ, Lavraud B, Reiff PH, Baumjohann W, Magnes W, Steller M, Lewis W, Saito Y, Coffey V, Chandler M. Electron-scale measurements of magnetic reconnection in space. Science 2016; 352:aaf2939. [PMID: 27174677 DOI: 10.1126/science.aaf2939] [Citation(s) in RCA: 438] [Impact Index Per Article: 54.8] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 01/20/2016] [Accepted: 05/03/2016] [Indexed: 11/02/2022]
Abstract
Magnetic reconnection is a fundamental physical process in plasmas whereby stored magnetic energy is converted into heat and kinetic energy of charged particles. Reconnection occurs in many astrophysical plasma environments and in laboratory plasmas. Using measurements with very high time resolution, NASA's Magnetospheric Multiscale (MMS) mission has found direct evidence for electron demagnetization and acceleration at sites along the sunward boundary of Earth's magnetosphere where the interplanetary magnetic field reconnects with the terrestrial magnetic field. We have (i) observed the conversion of magnetic energy to particle energy; (ii) measured the electric field and current, which together cause the dissipation of magnetic energy; and (iii) identified the electron population that carries the current as a result of demagnetization and acceleration within the reconnection diffusion/dissipation region.
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Affiliation(s)
- J L Burch
- Southwest Research Institute, San Antonio, TX, USA.
| | - R B Torbert
- Southwest Research Institute, San Antonio, TX, USA. University of New Hampshire, Durham, NH, USA
| | - T D Phan
- University of California, Berkeley, CA, USA
| | - L-J Chen
- University of Maryland, College Park, MD, USA
| | - T E Moore
- NASA, Goddard Space Flight Center, Greenbelt, MD, USA
| | - R E Ergun
- University of Colorado LASP, Boulder, CO, USA
| | - J P Eastwood
- Blackett Laboratory, Imperial College London, London, UK
| | - D J Gershman
- NASA, Goddard Space Flight Center, Greenbelt, MD, USA
| | - P A Cassak
- West Virginia University, Morgantown, WV, USA
| | - M R Argall
- University of New Hampshire, Durham, NH, USA
| | - S Wang
- University of Maryland, College Park, MD, USA
| | - M Hesse
- NASA, Goddard Space Flight Center, Greenbelt, MD, USA
| | - C J Pollock
- NASA, Goddard Space Flight Center, Greenbelt, MD, USA
| | - B L Giles
- NASA, Goddard Space Flight Center, Greenbelt, MD, USA
| | - R Nakamura
- Space Research Institute, Austrian Academy of Sciences, Graz, Austria
| | - B H Mauk
- Johns Hopkins University Applied Physics Laboratory, Laurel, MD, USA
| | - S A Fuselier
- Southwest Research Institute, San Antonio, TX, USA
| | - C T Russell
- University of California, Los Angeles, CA, USA
| | | | - J F Drake
- University of Maryland, College Park, MD, USA
| | - M A Shay
- University of Delaware, Newark, DE, USA
| | | | | | - G Marklund
- Royal Institute of Technology, Stockholm, Sweden
| | - F D Wilder
- University of Colorado LASP, Boulder, CO, USA
| | - D T Young
- Southwest Research Institute, San Antonio, TX, USA
| | - K Torkar
- Space Research Institute, Austrian Academy of Sciences, Graz, Austria
| | - J Goldstein
- Southwest Research Institute, San Antonio, TX, USA
| | - J C Dorelli
- NASA, Goddard Space Flight Center, Greenbelt, MD, USA
| | - L A Avanov
- NASA, Goddard Space Flight Center, Greenbelt, MD, USA
| | - M Oka
- University of California, Berkeley, CA, USA
| | - D N Baker
- University of Colorado LASP, Boulder, CO, USA
| | - A N Jaynes
- University of Colorado LASP, Boulder, CO, USA
| | | | - I J Cohen
- Johns Hopkins University Applied Physics Laboratory, Laurel, MD, USA
| | - D L Turner
- Aerospace Corporation, El Segundo, CA, USA
| | | | - J B Blake
- Aerospace Corporation, El Segundo, CA, USA
| | - J Clemmons
- Aerospace Corporation, El Segundo, CA, USA
| | - M Goldman
- University of Colorado, Boulder, CO, USA
| | - D Newman
- University of Colorado, Boulder, CO, USA
| | - S M Petrinec
- Lockheed Martin Advanced Technology Center, Palo Alto, CA, USA
| | | | - B Lavraud
- Institut de Recherche en Astrophysique et Planétologie, Toulouse, France
| | - P H Reiff
- Department of Physics and Astronomy, Rice University, Houston, TX, USA
| | - W Baumjohann
- Space Research Institute, Austrian Academy of Sciences, Graz, Austria
| | - W Magnes
- Space Research Institute, Austrian Academy of Sciences, Graz, Austria
| | - M Steller
- Space Research Institute, Austrian Academy of Sciences, Graz, Austria
| | - W Lewis
- Southwest Research Institute, San Antonio, TX, USA
| | - Y Saito
- Institute for Space and Astronautical Sciences, Sagamihara, Japan
| | - V Coffey
- NASA, Marshall Space Flight Center, Huntsville, AL, USA
| | - M Chandler
- NASA, Marshall Space Flight Center, Huntsville, AL, USA
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20
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Phan TD, Kluger R, Wan C. Minimally Invasive Cardiac Output Monitoring: Agreement of Oesophageal Doppler, LiDCOrapid™ and Vigileo FloTrac™ Monitors in Non-Cardiac Surgery. Anaesth Intensive Care 2016; 44:382-90. [DOI: 10.1177/0310057x1604400313] [Citation(s) in RCA: 10] [Impact Index Per Article: 1.3] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/17/2022]
Abstract
There is lack of data about the agreement of minimally invasive cardiac output monitors, which make it impossible to determine if they are interchangeable or differ objectively in tracking physiological trends. We studied three commonly used devices: the oesophageal Doppler and two arterial pressure–based devices, the Vigileo FloTrac™ and LiDCOrapid™. The aim of this study was to compare the agreement of these three monitors in adult patients undergoing elective non-cardiac surgery. Measurements were taken at baseline and after predefined clinical interventions of fluid, metaraminol or ephedrine bolus. From 24 patients, 131 events, averaging 5.2 events per patient, were analysed. The cardiac index of LiDCOrapid versus FloTrac had a mean bias of −6.0% (limits of agreement from −51% to 39%) and concordance of over 80% to the three clinical interventions. The cardiac index of Doppler versus LiDCOrapid and Doppler versus FloTrac, had an increasing negative bias at higher mean cardiac outputs and there was significantly poorer concordance to all interventions. Of the preload-responsive parameters, Doppler stroke volume index, Doppler systolic flow time and FloTrac stroke volume variation were fair at predicting fluid responsiveness while other parameters were poor. While there is reasonable agreement between the two arterial pressure–derived cardiac output devices (LiDCOrapid and Vigileo FloTrac), these two devices differ significantly to the oesophageal Doppler technology in response to common clinical intraoperative interventions, representing a limitation to how interchangeable these technologies are in measuring cardiac output.
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Affiliation(s)
- T. D. Phan
- Department of Anaesthesia and Acute Pain Medicine, St Vincent's Hospital, University of Melbourne, Melbourne, Victoria
| | - R. Kluger
- Department of Anaesthesia and Acute Pain Medicine, St Vincent's Hospital, University of Melbourne, Melbourne, Victoria
| | - C. Wan
- Department of Anaesthesia and Acute Pain Medicine, St Vincent's Hospital, University of Melbourne, Melbourne, Victoria
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21
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Mozer FS, Agapitov OA, Artemyev A, Burch JL, Ergun RE, Giles BL, Mourenas D, Torbert RB, Phan TD, Vasko I. Magnetospheric Multiscale Satellite Observations of Parallel Electron Acceleration in Magnetic Field Reconnection by Fermi Reflection from Time Domain Structures. Phys Rev Lett 2016; 116:145101. [PMID: 27104714 DOI: 10.1103/physrevlett.116.145101] [Citation(s) in RCA: 3] [Impact Index Per Article: 0.4] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [Track Full Text] [Subscribe] [Scholar Register] [Received: 01/27/2016] [Indexed: 06/05/2023]
Abstract
The same time domain structures (TDS) have been observed on two Magnetospheric Multiscale Satellites near Earth's dayside magnetopause. These TDS, traveling away from the X line along the magnetic field at 4000 km/s, accelerated field-aligned ∼5 eV electrons to ∼200 eV by a single Fermi reflection of the electrons by these overtaking barriers. Additionally, the TDS contained both positive and negative potentials, so they were a mixture of electron holes and double layers. They evolve in ∼10 km of space or 7 ms of time and their spatial scale size is 10-20 km, which is much larger than the electron gyroradius (<1 km) or the electron inertial length (4 km at the observation point, less nearer the X line).
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Affiliation(s)
- F S Mozer
- Space Sciences Laboratory, University of California, Berkeley, California 94720, USA
- Taras Shevchenko National University of Kyiv, Glushkova Avenue, 4, Kyiv 01601, Ukraine
- Institute of Geophysics and Planetary Physics, University of California, Los Angeles, California 90002, USA
- Southwest Research Institute, San Antonio, Texas 78238, USA
- LASP, University of Colorado, Boulder, Colorado 80303, USA
- NASA Goddard Space Flight Center, Greenbelt, Maryland 20771, USA
- LPC2 E/CNRS-University of Orleans, Orleans 45100, France
- University of New Hampshire, Durham, New Hampshire 03824, USA
- Space Research Institute, Russian Academy of Science, Moscow, Russia 117342
| | - O A Agapitov
- Space Sciences Laboratory, University of California, Berkeley, California 94720, USA
- Taras Shevchenko National University of Kyiv, Glushkova Avenue, 4, Kyiv 01601, Ukraine
| | - A Artemyev
- Institute of Geophysics and Planetary Physics, University of California, Los Angeles, California 90002, USA
- Space Research Institute, Russian Academy of Science, Moscow, Russia 117342
| | - J L Burch
- Southwest Research Institute, San Antonio, Texas 78238, USA
| | - R E Ergun
- LASP, University of Colorado, Boulder, Colorado 80303, USA
| | - B L Giles
- NASA Goddard Space Flight Center, Greenbelt, Maryland 20771, USA
| | - D Mourenas
- LPC2 E/CNRS-University of Orleans, Orleans 45100, France
| | - R B Torbert
- University of New Hampshire, Durham, New Hampshire 03824, USA
| | - T D Phan
- Space Sciences Laboratory, University of California, Berkeley, California 94720, USA
| | - I Vasko
- Space Research Institute, Russian Academy of Science, Moscow, Russia 117342
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22
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Pham HTT, Antoine-Moussiaux N, Grosbois V, Moula N, Truong BD, Phan TD, Vu TD, Trinh TQ, Vu CC, Rukkwamsuk T, Peyre M. Financial Impacts of Priority Swine Diseases to Pig Farmers in Red River and Mekong River Delta, Vietnam. Transbound Emerg Dis 2016; 64:1168-1177. [DOI: 10.1111/tbed.12482] [Citation(s) in RCA: 11] [Impact Index Per Article: 1.4] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 09/10/2015] [Indexed: 11/28/2022]
Affiliation(s)
- H. T. T. Pham
- French Agricultural Research Center for International Development (CIRAD); Animal and Integrated Risk Management Research Unit (AGIRs); Montpellier France
- Kasetsart University; Bangkok Thailand
- National Institute of Animal Science; Hanoi Vietnam
| | - N. Antoine-Moussiaux
- Fundamental and Applied Research for Animals & Health (FARAH); University of Liège; Liège Belgium
| | - V. Grosbois
- French Agricultural Research Center for International Development (CIRAD); Animal and Integrated Risk Management Research Unit (AGIRs); Montpellier France
| | - N. Moula
- Fundamental and Applied Research for Animals & Health (FARAH); University of Liège; Liège Belgium
| | - B. D. Truong
- Nong Lam University of Agriculture; Ho Chi Minh city Vietnam
| | - T. D. Phan
- Center for Interdisciplinary Research on Rural Development (CIRRD); Vietnam National University of Agriculture; Hanoi Vietnam
| | - T. D. Vu
- Center for Interdisciplinary Research on Rural Development (CIRRD); Vietnam National University of Agriculture; Hanoi Vietnam
| | - T. Q. Trinh
- National Institute of Animal Science; Hanoi Vietnam
| | - C. C. Vu
- National Institute of Animal Science; Hanoi Vietnam
| | | | - M. Peyre
- French Agricultural Research Center for International Development (CIRAD); Animal and Integrated Risk Management Research Unit (AGIRs); Montpellier France
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23
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Hietala H, Drake JF, Phan TD, Eastwood JP, McFadden JP. Ion temperature anisotropy across a magnetotail reconnection jet. Geophys Res Lett 2015; 42:7239-7247. [PMID: 27478283 PMCID: PMC4950132 DOI: 10.1002/2015gl065168] [Citation(s) in RCA: 2] [Impact Index Per Article: 0.2] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [Key Words] [Track Full Text] [Subscribe] [Scholar Register] [Received: 06/30/2015] [Revised: 08/17/2015] [Accepted: 08/19/2015] [Indexed: 06/02/2023]
Abstract
A significant fraction of the energy released by magnetotail reconnection appears to go into ion heating, but this heating is generally anisotropic. We examine ARTEMIS dual-spacecraft observations of a long-duration magnetotail exhaust generated by antiparallel reconnection in conjunction with particle-in-cell simulations, showing spatial variations in the anisotropy across the outflow far (>100di ) downstream of the X line. A consistent pattern is found in both the spacecraft data and the simulations: While the total temperature across the exhaust is rather constant, near the boundaries Ti,|| dominates. The plasma is well above the firehose threshold within patchy spatial regions at |BX |∈[0.1,0.5]B0, suggesting that the drive for the instability is strong and the instability is too weak to relax the anisotropy. At the midplane ( |BX|≲0.1B0), Ti,⊥>Ti,|| and ions undergo Speiser-like motion despite the large distance from the X line.
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Affiliation(s)
- H. Hietala
- The Blackett LaboratoryImperial CollegeLondonUK
| | - J. F. Drake
- Department of Physics, the Institute for Physical Science and Technology and the Joint Space InstituteUniversity of MarylandCollege ParkMarylandUSA
| | - T. D. Phan
- Space Science LaboratoryUniversity of CaliforniaBerkeleyCaliforniaUSA
| | | | - J. P. McFadden
- Space Science LaboratoryUniversity of CaliforniaBerkeleyCaliforniaUSA
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Delabouglise A, Antoine-Moussiaux N, Phan TD, Dao DC, Nguyen TT, Truong BD, Nguyen XNT, Vu TD, Nguyen KV, Le HT, Salem G, Peyre M. The Perceived Value of Passive Animal Health Surveillance: The Case of Highly Pathogenic Avian Influenza in Vietnam. Zoonoses Public Health 2015; 63:112-28. [PMID: 26146982 PMCID: PMC4758386 DOI: 10.1111/zph.12212] [Citation(s) in RCA: 28] [Impact Index Per Article: 3.1] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 01/16/2015] [Indexed: 12/01/2022]
Abstract
Economic evaluations are critical for the assessment of the efficiency and sustainability of animal health surveillance systems and the improvement of their efficiency. Methods identifying and quantifying costs and benefits incurred by public and private actors of passive surveillance systems (i.e. actors of veterinary authorities and private actors who may report clinical signs) are needed. This study presents the evaluation of perceived costs and benefits of highly pathogenic avian influenza (HPAI) passive surveillance in Vietnam. Surveys based on participatory epidemiology methods were conducted in three provinces in Vietnam to collect data on costs and benefits resulting from the reporting of HPAI suspicions to veterinary authorities. A quantitative tool based on stated preference methods and participatory techniques was developed and applied to assess the non-monetary costs and benefits. The study showed that poultry farmers are facing several options regarding the management of HPAI suspicions, besides reporting the following: treatment, sale or destruction of animals. The option of reporting was associated with uncertain outcome and transaction costs. Besides, actors anticipated the release of health information to cause a drop of markets prices. This cost was relevant at all levels, including farmers, veterinary authorities and private actors of the upstream sector (feed, chicks and medicine supply). One benefit associated with passive surveillance was the intervention of public services to clean farms and the environment to limit the disease spread. Private actors of the poultry sector valued information on HPAI suspicions (perceived as a non-monetary benefit) which was mainly obtained from other private actors and media.
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Affiliation(s)
- A Delabouglise
- AGIRs-Animal and Integrated Risk Management Research Unit, CIRAD-French Agricultural Research Center for International Development, Montpellier, France.,LADYSS, Enjeux Sanitaires et Territoires, CNRS, University Paris-ouest Nanterre-La Défense, Nanterre, France
| | - N Antoine-Moussiaux
- AGIRs-Animal and Integrated Risk Management Research Unit, CIRAD-French Agricultural Research Center for International Development, Montpellier, France.,FARAH-Fundamental and Applied Research for Animals & Health, University of Liège, Liège, Belgium
| | - T D Phan
- Center for Interdisciplinary Research on Rural Development, Vietnam National University of Agriculture, Hanoi, Vietnam
| | - D C Dao
- Faculty of Veterinary Medicine, Vietnam National University of Agriculture, Hanoi, Vietnam
| | - T T Nguyen
- National Institute of Veterinary Research, Hanoi, Vietnam
| | - B D Truong
- Faculty of Animal Science and Veterinary Medicine, Nong Lam University, Ho Chi Minh City, Vietnam
| | - X N T Nguyen
- Faculty of Animal Science and Veterinary Medicine, Nong Lam University, Ho Chi Minh City, Vietnam
| | - T D Vu
- Center for Interdisciplinary Research on Rural Development, Vietnam National University of Agriculture, Hanoi, Vietnam
| | - K V Nguyen
- National Institute of Veterinary Research, Hanoi, Vietnam
| | - H T Le
- Faculty of Animal Science and Veterinary Medicine, Nong Lam University, Ho Chi Minh City, Vietnam
| | - G Salem
- LADYSS, Enjeux Sanitaires et Territoires, CNRS, University Paris-ouest Nanterre-La Défense, Nanterre, France
| | - M Peyre
- AGIRs-Animal and Integrated Risk Management Research Unit, CIRAD-French Agricultural Research Center for International Development, Montpellier, France.,National Institute of Veterinary Research, Hanoi, Vietnam
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Phan TD, An V, D'Souza B, Rattray MJ, Johnston MJ, Cowie BS. A Randomised Controlled Trial of Fluid Restriction Compared to Oesophageal Doppler-Guided Goal-Directed Fluid Therapy in Elective Major Colorectal Surgery within an Enhanced Recovery after Surgery Program. Anaesth Intensive Care 2014; 42:752-60. [DOI: 10.1177/0310057x1404200611] [Citation(s) in RCA: 75] [Impact Index Per Article: 7.5] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 02/04/2023]
Abstract
There is continued controversy regarding the benefits of goal-directed fluid therapy, with earlier studies showing marked improvement in morbidity and length-of-stay that have not been replicated more recently. The aim of this study was to compare patient outcomes in elective colorectal surgery patients having goal-directed versus restrictive fluid therapy. Inclusion criteria included suitability for an Enhanced Recovery After Surgery care pathway and patients with an American Society of Anesthesiologists Physical Status score of 1 to 3. Patients were intraoperatively randomised to either restrictive or Doppler-guided goal-directed fluid therapy. The primary outcome was length-of-stay; secondary outcomes included complication rate, change in haemodynamic variables and fluid volumes. One hundred patients, 50 in each group, were included in the analysis. Compared to restrictive therapy, goal-directed therapy resulted in a greater volume of intraoperative fluid, 2115 (interquartile range 1350 to 2560) ml versus 1500 (1200 to 2000) ml, P=0.008, and was associated with an increase in Doppler-derived stroke volume index from beginning to end of surgery, 43.7 (16.3) to 54.2 (21.1) ml/m2, P <0.001, in the latter group. Length-of-stay was similar, P=0.421. The number of patients with any complication (minor or major) was similar; 60% (30) versus 52% (26), P=0.42, or major complications, 1 (2%) versus 4 (8%), P=0.36, respectively. The increased perioperative fluid volumes and increased stroke volumes at the end of surgery in patients receiving goal-directed therapy did not translate to a significant difference in length-of-stay and we did not observe a difference in the number of patients experiencing minor or major complications.
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Affiliation(s)
- T. D. Phan
- Department of Anaesthesia, University of Melbourne, St Vincent's Hospital, Melbourne, Victoria
| | - V. An
- Department of Anaesthesia, University of Melbourne, St Vincent's Hospital, Melbourne, Victoria
- Department of Colorectal Surgery, St Vincent's Hospital, Fitzroy, Victoria
| | - B. D'Souza
- Department of Anaesthesia, University of Melbourne, St Vincent's Hospital, Melbourne, Victoria
- Department of Colorectal Surgery, St Vincent's Hospital, Fitzroy, Victoria
| | - M. J. Rattray
- Department of Anaesthesia, University of Melbourne, St Vincent's Hospital, Melbourne, Victoria
| | - M. J. Johnston
- Department of Anaesthesia, University of Melbourne, St Vincent's Hospital, Melbourne, Victoria
- Department of Colorectal Surgery, St Vincent's Hospital, Melbourne, Victoria
| | - B. S. Cowie
- Department of Anaesthesia, University of Melbourne, St Vincent's Hospital, Melbourne, Victoria
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Phan TD, Nguyen V, Cowie B. Fluid responsiveness in healthy volunteers: data precision and significance. Anaesthesia 2014; 69:789-90. [DOI: 10.1111/anae.12758] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/29/2022]
Affiliation(s)
- T. D. Phan
- St Vincent's Hospital Melbourne; Victoria Australia
| | - V. Nguyen
- St Vincent's Hospital Melbourne; Victoria Australia
| | - B. Cowie
- St Vincent's Hospital Melbourne; Victoria Australia
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Eastwood JP, Phan TD, Drake JF, Shay MA, Borg AL, Lavraud B, Taylor MGGT. Energy partition in magnetic reconnection in Earth's magnetotail. Phys Rev Lett 2013; 110:225001. [PMID: 23767730 DOI: 10.1103/physrevlett.110.225001] [Citation(s) in RCA: 4] [Impact Index Per Article: 0.4] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [Track Full Text] [Subscribe] [Scholar Register] [Received: 10/15/2012] [Indexed: 06/02/2023]
Abstract
The partition of energy flux in magnetic reconnection is examined experimentally using Cluster satellite observations of collisionless reconnection in Earth's magnetotail. In this plasma regime, the dominant component of the energy flux is ion enthalpy flux, with smaller contributions from the electron enthalpy and heat flux and the ion kinetic energy flux. However, the Poynting flux is not negligible, and in certain parts of the ion diffusion region the Poynting flux in fact dominates. Evidence for earthward-tailward asymmetry is ascribed to the presence of Earth's dipole fields.
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Affiliation(s)
- J P Eastwood
- The Blackett Laboratory, Imperial College London, London SW7 2AZ, United Kingdom.
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Huynh Q, Phan TD, Thieu VQQ, Tran ST, Do SH. Extraction and refining of essential oil from Australian tea tree, Melaleuca alterfornia, and the antimicrobial activity in cosmetic products. ACTA ACUST UNITED AC 2012. [DOI: 10.1088/1742-6596/352/1/012053] [Citation(s) in RCA: 9] [Impact Index Per Article: 0.8] [Reference Citation Analysis] [What about the content of this article? (0)] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/12/2022]
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Phan TD, Kluger R, Wan C, Wong D, Padayachee A. A Comparison of Three Minimally Invasive Cardiac Output Devices with Thermodilution in Elective Cardiac Surgery. Anaesth Intensive Care 2011; 39:1014-21. [DOI: 10.1177/0310057x1103900606] [Citation(s) in RCA: 26] [Impact Index Per Article: 2.0] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 01/26/2023]
Abstract
This study compared the cardiac output responses to haemodynamic interventions as measured by three minimally invasive monitors (Oesophageal Doppler Monitor, the VigileoFlotrac and the LiDCOrapid) to the responses measured concurrently using thermodilution, in cardiac surgical patients. The study also assessed the precision and bias of these monitors in relation to thermodilution measurements. After a fluid bolus of at least 250 ml, the measured change in cardiac output was different among the devices, showing an increase with thermodilution in 82% of measurements, Oesophageal Doppler Monitor 68%, VigileoFlotrac 57% and LiDCOrapid 41%. When comparing the test devices to thermodilution, the kappa statistic showed at best only fair agreement, Oesophageal Doppler Monitor 0.34, LiDCOrapid 0.28 and VigileoFlotrac -0.03. After vasopressor administration, there was also significant variation in the change in cardiac output measured by the devices. Using Bland-Altman analysis, the precision of the devices in comparison to thermodilution showed minimal bias, but wide limits of agreement with percentage errors of Oesophageal Doppler Monitor 64.5%, VigileoFlotrac 47.6% and LiDCOrapid 54.2%. These findings indicate that these three devices differ in their responses, do not always provide the same information as thermodilution and should not be used interchangeably to track cardiac output changes.
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Affiliation(s)
- T. D. Phan
- Department of Anaesthesia, St Vincent's Hospital, Fitzroy, Victoria, Australia
| | - R. Kluger
- Department of Anaesthesia, St Vincent's Hospital, Fitzroy, Victoria, Australia
| | - C. Wan
- Department of Anaesthesia, St Vincent's Hospital, Fitzroy, Victoria, Australia
| | - D. Wong
- Department of Anaesthesia, St Vincent's Hospital, Fitzroy, Victoria, Australia
| | - A. Padayachee
- Department of Anaesthesia, St Vincent's Hospital, Fitzroy, Victoria, Australia
- Department of Anaesthesia, Christchurch Hospital, Christchurch, New Zealand
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30
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Øieroset M, Phan TD, Eastwood JP, Fujimoto M, Daughton W, Shay MA, Angelopoulos V, Mozer FS, McFadden JP, Larson DE, Glassmeier KH. Direct evidence for a three-dimensional magnetic flux rope flanked by two active magnetic reconnection X lines at Earth's magnetopause. Phys Rev Lett 2011; 107:165007. [PMID: 22107399 DOI: 10.1103/physrevlett.107.165007] [Citation(s) in RCA: 2] [Impact Index Per Article: 0.2] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [Track Full Text] [Subscribe] [Scholar Register] [Received: 06/20/2011] [Indexed: 05/31/2023]
Abstract
We report the direct detection by three THEMIS spacecraft of a magnetic flux rope flanked by two active X lines producing colliding plasma jets near the center of the flux rope. The observed density depletion and open magnetic field topology inside the flux rope reveal important three-dimensional effects. There was also evidence for nonthermal electron energization within the flux rope core where the fluxes of 1-4 keV superthermal electrons were higher than those in the converging reconnection jets. The observed ion and electron energizations differ from current theoretical predictions.
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Affiliation(s)
- M Øieroset
- Space Sciences Laboratory, University of California, Berkeley, Berkeley, California 94720, USA
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31
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Shay MA, Drake JF, Eastwood JP, Phan TD. Super-Alfvénic propagation of substorm reconnection signatures and Poynting flux. Phys Rev Lett 2011; 107:065001. [PMID: 21902330 DOI: 10.1103/physrevlett.107.065001] [Citation(s) in RCA: 3] [Impact Index Per Article: 0.2] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [Track Full Text] [Subscribe] [Scholar Register] [Received: 11/01/2010] [Indexed: 05/31/2023]
Abstract
The propagation of reconnection signatures and their associated energy are examined using kinetic particle-in-cell simulations and Cluster satellite observations. It is found that the quadrupolar out-of-plane magnetic field near the separatrices is associated with a kinetic Alfvén wave. For magnetotail parameters, the parallel propagation of this wave is super-Alfvénic (V(∥) ∼ 1500-5500 km/s) and generates substantial Poynting flux (S ∼ 10(-5)-10(-4) W/m(2)) consistent with Cluster observations of magnetic reconnection. This Poynting flux substantially exceeds that due to frozen-in ion bulk outflows and is sufficient to generate white light aurora in Earth's ionosphere.
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Affiliation(s)
- M A Shay
- Department of Physics and Astronomy, University of Delaware, Newark, 19716, USA.
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Eastwood JP, Shay MA, Phan TD, Øieroset M. Asymmetry of the ion diffusion region Hall electric and magnetic fields during guide field reconnection: observations and comparison with simulations. Phys Rev Lett 2010; 104:205001. [PMID: 20867032 DOI: 10.1103/physrevlett.104.205001] [Citation(s) in RCA: 2] [Impact Index Per Article: 0.1] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [Track Full Text] [Subscribe] [Scholar Register] [Received: 11/16/2009] [Indexed: 05/29/2023]
Abstract
In situ measurements of magnetic reconnection in the Earth's magnetotail are presented showing that even a moderate guide field (20% of the reconnecting field) considerably distorts ion diffusion region structure. The Hall magnetic and electric fields are asymmetric and shunted away from the current sheet; an appropriately scaled particle-in-cell simulation is found to be in excellent agreement with the data. The results show the importance of correctly accounting for the effects of the magnetic shear when attempting to identify and study magnetic reconnection diffusion regions in nature.
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Affiliation(s)
- J P Eastwood
- The Blackett Laboratory, Imperial College London, London SW7 2AZ, United Kingdom.
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Eastwood JP, Phan TD, Bale SD, Tjulin A. Observations of turbulence generated by magnetic reconnection. Phys Rev Lett 2009; 102:035001. [PMID: 19257361 DOI: 10.1103/physrevlett.102.035001] [Citation(s) in RCA: 9] [Impact Index Per Article: 0.6] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [Track Full Text] [Subscribe] [Scholar Register] [Received: 06/17/2008] [Indexed: 05/27/2023]
Abstract
Spacecraft observations of turbulence within a magnetic reconnection (guide field approximately 0) ion diffusion region are presented. In the inertial subrange, electric and magnetic fluctuations both followed a -5/3 power law; at higher frequencies, the spectral indices were -1 and -8/3, respectively. The dispersion relation was found to be consistent with fast-mode-whistler waves rather than kinetic Alfvén-ion cyclotron waves. Lower hybrid waves, which could be enhanced by whistler mode conversion, were observed, but the associated anomalous resistivity was not found to significantly modify the reconnection rate.
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Affiliation(s)
- J P Eastwood
- Space Sciences Laboratory, University of California, Berkeley, California 94720-7450, USA.
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Phan TD, Drake JF, Shay MA, Mozer FS, Eastwood JP. Evidence for an elongated (>60 ion skin depths) electron diffusion region during fast magnetic reconnection. Phys Rev Lett 2007; 99:255002. [PMID: 18233527 DOI: 10.1103/physrevlett.99.255002] [Citation(s) in RCA: 2] [Impact Index Per Article: 0.1] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [Track Full Text] [Subscribe] [Scholar Register] [Received: 10/09/2007] [Indexed: 05/25/2023]
Abstract
Observations of an extremely elongated electron diffusion region occurring during fast reconnection are presented. Cluster spacecraft in situ observations of an expanding reconnection exhaust reveal a broad current layer ( approximately 10 ion skin depths thick) supporting the reversal of the reconnecting magnetic field together with an intense current embedded at the center that is due to a super-Alfvénic electron outflow jet with transverse scale of approximately 9 electron skin depths. The electron jet extends at least 60 ion skin depths downstream from the X-line.
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Affiliation(s)
- T D Phan
- Space Sciences Laboratory, University of California, Berkeley, California 94720, USA
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35
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Phan TD, Walpole AG. A cause for a non-invasive blood pressure cuff leak. Anaesth Intensive Care 2006; 34:826-7. [PMID: 17183908] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [What about the content of this article? (0)] [MESH Headings] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 05/13/2023]
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Phan TD, Lau KKP, De Campo J. Stratification of radiological test ordering: Its usefulness in reducing unnecessary tests with consequential reduction in costs. ACTA ACUST UNITED AC 2006; 50:335-8. [PMID: 16884419 DOI: 10.1111/j.1440-1673.2006.01593.x] [Citation(s) in RCA: 5] [Impact Index Per Article: 0.3] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 01/22/2023]
Abstract
This study examines the effectiveness of an automated, stratified system of radiological test ordering, known as 'Traffic Lights', in reducing the number of unnecessary tests and their associated costs. The system involves stratification of radiological tests into three groups, denoted by red, amber and green colours. 'Red' tests must be authorized by a consultant. 'Amber' tests must be signed by a registrar or authorized by a consultant. 'Green' tests can be ordered directly by residents or interns. In the 4 months after the introduction of 'Traffic Lights', each radiological method showed a reduction in both the number of tests and their associated costs. The reduction was consistent across both medical and surgical groups. Analysis of data 20 months immediately after the introduction of 'Traffic Lights' also showed a consistent reduction in the total number of tests, suggesting that the changes are sustainable and unlikely to be due to seasonal variation. Combined with evidence-based medicine protocols, this stratified system of radiological test ordering should ensure the safety, quality and appropriateness of imaging tests and minimize overall patient radiation dose.
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Affiliation(s)
- T D Phan
- Department of Diagnostic Imaging, Monash Medical Centre, Southern Health, Melbourne, Victoria, Australia.
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Phan TD, Gosling JT, Davis MS, Skoug RM, Øieroset M, Lin RP, Lepping RP, McComas DJ, Smith CW, Reme H, Balogh A. A magnetic reconnection X-line extending more than 390 Earth radii in the solar wind. Nature 2006; 439:175-8. [PMID: 16407946 DOI: 10.1038/nature04393] [Citation(s) in RCA: 249] [Impact Index Per Article: 13.8] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 08/30/2005] [Accepted: 10/31/2005] [Indexed: 11/09/2022]
Abstract
Magnetic reconnection in a current sheet converts magnetic energy into particle energy, a process that is important in many laboratory, space and astrophysical contexts. It is not known at present whether reconnection is fundamentally a process that can occur over an extended region in space or whether it is patchy and unpredictable in nature. Frequent reports of small-scale flux ropes and flow channels associated with reconnection in the Earth's magnetosphere raise the possibility that reconnection is intrinsically patchy, with each reconnection X-line (the line along which oppositely directed magnetic field lines reconnect) extending at most a few Earth radii (R(E)), even though the associated current sheets span many tens or hundreds of R(E). Here we report three-spacecraft observations of accelerated flow associated with reconnection in a current sheet embedded in the solar wind flow, where the reconnection X-line extended at least 390R(E) (or 2.5 x 10(6) km). Observations of this and 27 similar events imply that reconnection is fundamentally a large-scale process. Patchy reconnection observed in the Earth's magnetosphere is therefore likely to be a geophysical effect associated with fluctuating boundary conditions, rather than a fundamental property of reconnection. Our observations also reveal, surprisingly, that reconnection can operate in a quasi-steady-state manner even when undriven by the external flow.
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Affiliation(s)
- T D Phan
- Space Sciences Laboratory, University of California, Berkeley, California 94720, USA.
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Abstract
A 26-year-old man with a history of heavy marijuana and minimal tobacco use was found to have extensive bilateral lung bullae and interstitial fibrosis, heavily infiltrated by pigmented macrophages. These features can be associated with marijuana smoking. The differential diagnoses in this patient are also discussed.
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Affiliation(s)
- T D Phan
- Department of Diagnostic Imaging, Monash Medical Centre, Clayton Road, Melbourne, Victoria 3168, Australia
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Chaston CC, Phan TD, Bonnell JW, Mozer FS, Acuńa M, Goldstein ML, Balogh A, Andre M, Reme H, Fazakerley A. Drift-kinetic Alfvén waves observed near a reconnection X line in the earth's magnetopause. Phys Rev Lett 2005; 95:065002. [PMID: 16090960 DOI: 10.1103/physrevlett.95.065002] [Citation(s) in RCA: 4] [Impact Index Per Article: 0.2] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [Track Full Text] [Subscribe] [Scholar Register] [Received: 01/26/2005] [Indexed: 05/03/2023]
Abstract
We identify drift-kinetic Alfvén waves in the vicinity of a reconnection X line on the Earth's magnetopause. The dispersive properties of these waves have been determined using wavelet interferometric techniques applied to multipoint observations from the Cluster spacecraft. Comparison of the observed wave dispersion with that expected for drift-kinetic Alfvén waves shows close agreement. The waves propagate outwards from the X line suggesting that reconnection is a kinetic Alfvén wave source. Energetic O+ ions observed in these waves indicate that reconnection is a driver of auroral ion outflow.
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Affiliation(s)
- C C Chaston
- Space Science Laboratory, University of California, Berkeley, California 94720, USA
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Vaivads A, Khotyaintsev Y, André M, Retinò A, Buchert SC, Rogers BN, Décréau P, Paschmann G, Phan TD. Structure of the magnetic reconnection diffusion region from four-spacecraft observations. Phys Rev Lett 2004; 93:105001. [PMID: 15447408 DOI: 10.1103/physrevlett.93.105001] [Citation(s) in RCA: 14] [Impact Index Per Article: 0.7] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [Track Full Text] [Subscribe] [Scholar Register] [Received: 04/22/2004] [Indexed: 05/24/2023]
Abstract
Magnetic reconnection leads to energy conversion in large volumes in space but is initiated in small diffusion regions. Because of the small sizes of the diffusion regions, their crossings by spacecraft are rare. We report four-spacecraft observations of a diffusion region encounter at the Earth's magnetopause that allow us to reliably distinguish spatial from temporal features. We find that the diffusion region is stable on ion time and length scales in agreement with numerical simulations. The electric field normal to the current sheet is balanced by the Hall term in the generalized Ohm's law, E(n) approximately jxB/ne.n, thus establishing that Hall physics is dominating inside the diffusion region. The reconnection rate is fast, approximately 0.1. We show that strong parallel currents flow along the separatrices; they are correlated with observations of high-frequency Langmuir/upper hybrid waves.
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Affiliation(s)
- A Vaivads
- Swedish Institute of Space Physics, Uppsala, Sweden
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Mozer FS, Bale SD, Phan TD, Osborne JA. Observations of electron diffusion regions at the subsolar magnetopause. Phys Rev Lett 2003; 91:245002. [PMID: 14683131 DOI: 10.1103/physrevlett.91.245002] [Citation(s) in RCA: 2] [Impact Index Per Article: 0.1] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [Track Full Text] [Subscribe] [Scholar Register] [Received: 06/17/2003] [Indexed: 05/24/2023]
Abstract
Electric and magnetic field observations on the Polar satellite at the subsolar magnetopause show that the magnetopause current is often striated. The largest of the resulting current channels are interpreted as electron diffusion regions because their widths are several electron skin depths and the electron flow U(e) within them does not satisfy E-->+U-->(e)xB-->=0. The data suggest that the magnetopause contains many such electron diffusion regions and that they are required because E-->xB-->/B(2) drifting electrons cannot carry the large filamentary currents imposed on the local plasma. The most probable interpretation of E-->+U-->(e)xB--> not equal 0 is that the pressure term on the right side of the generalized Ohm's law balances this inequality.
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Affiliation(s)
- F S Mozer
- Space Sciences Laboratory, University of California, Berkeley, California, 94720, USA
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Frey HU, Phan TD, Fuselier SA, Mende SB. Continuous magnetic reconnection at Earth's magnetopause. Nature 2003; 426:533-7. [PMID: 14654835 DOI: 10.1038/nature02084] [Citation(s) in RCA: 110] [Impact Index Per Article: 5.2] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 06/13/2003] [Accepted: 09/23/2003] [Indexed: 11/09/2022]
Abstract
The most important process that allows solar-wind plasma to cross the magnetopause and enter Earth's magnetosphere is the merging between solar-wind and terrestrial magnetic fields of opposite sense-magnetic reconnection. It is at present not known whether reconnection can happen in a continuous fashion or whether it is always intermittent. Solar flares and magnetospheric substorms--two phenomena believed to be initiated by reconnection--are highly burst-like occurrences, raising the possibility that the reconnection process is intrinsically intermittent, storing and releasing magnetic energy in an explosive and uncontrolled manner. Here we show that reconnection at Earth's high-latitude magnetopause is driven directly by the solar wind, and can be continuous and even quasi-steady over an extended period of time. The dayside proton auroral spot in the ionosphere--the remote signature of high-latitude magnetopause reconnection--is present continuously for many hours. We infer that reconnection is not intrinsically intermittent; its steadiness depends on the way that the process is driven.
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Affiliation(s)
- H U Frey
- Space Sciences Laboratory, University of California, Berkeley, California 94720-7450, USA.
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ØIeroset M, Lin RP, Phan TD, Larson DE, Bale SD. Evidence for electron acceleration up to approximately 300 keV in the magnetic reconnection diffusion region of earth's magnetotail. Phys Rev Lett 2002; 89:195001. [PMID: 12443119 DOI: 10.1103/physrevlett.89.195001] [Citation(s) in RCA: 32] [Impact Index Per Article: 1.5] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [Track Full Text] [Subscribe] [Scholar Register] [Received: 06/28/2002] [Indexed: 05/24/2023]
Abstract
We report direct measurements of high-energy particles in a rare crossing of the diffusion region in Earth's magnetotail by the Wind spacecraft. The fluxes of energetic electrons up to approximately 300 keV peak near the center of the diffusion region and decrease monotonically away from this region. The diffusion region electron flux spectrum obeys a power law with an index of -3.8 above approximately 2 keV, and the electron angular distribution displays strong field-aligned bidirectional anisotropy at energies below approximately 2 keV, becoming isotropic above approximately 6 keV. These observations indicate significant electron acceleration inside the diffusion region. Ions show no such energization.
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Affiliation(s)
- M ØIeroset
- Space Sciences Laboratory, University of California, Berkeley, California 94720, USA
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Abstract
On 1 April 2001, the Polar satellite crossed a subsolar magnetopause associated with antiparallel magnetic fields. Over a width approximately 6 magnetosheath ion skin depths (approximately 3 magnetospheric ion skin depths), perpendicular ion flows different from E x B/B(2) as well as Hall magnetic and electric field signatures were observed. At a smaller scale, the electron flow decoupled from the magnetic field near a deep minimum in the magnetic field strength. Separatrices were identified as boundaries of low frequency electric field turbulence associated with density minima and parallel electric fields. The reconnection rate was less than 2% of the asymptotic Alfvén speed.
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Affiliation(s)
- F S Mozer
- Space Sciences Laboratory, University of California, Berkeley, California 94720, USA
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Abstract
Magnetic reconnection is the process by which magnetic field lines of opposite polarity reconfigure to a lower-energy state, with the release of magnetic energy to the surroundings. Reconnection at the Earth's dayside magnetopause and in the magnetotail allows the solar wind into the magnetosphere. It begins in a small 'diffusion region', where a kink in the newly reconnected lines produces jets of plasma away from the region. Although plasma jets from reconnection have previously been reported, the physical processes that underlie jet formation have remained poorly understood because of the scarcity of in situ observations of the minuscule diffusion region. Theoretically, both resistive and collisionless processes can initiate reconnection, but which process dominates in the magnetosphere is still debated. Here we report the serendipitous encounter of the Wind spacecraft with an active reconnection diffusion region, in which are detected key processes predicted by models of collisionless reconnection. The data therefore demonstrate that collisionless reconnection occurs in the magnetotail.
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Affiliation(s)
- M Oieroset
- Space Sciences Laboratory, University of California, Berkeley, California 94720, USA.
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Sibeck DG, Borodkova NL, Schwartz SJ, Owen CJ, Kessel R, Kokubun S, Lepping RP, Lin R, Liou K, Lühr H, McEntire RW, Meng CI, Mukai T, Nemecek Z, Parks G, Phan TD, Romanov SA, Safrankova J, Sauvaud JA, Singer HJ, Solovyev SI, Szabo A, Takahashi K, Williams DJ, Yumoto K, Zastenker GN. Comprehensive study of the magnetospheric response to a hot flow anomaly. ACTA ACUST UNITED AC 1999. [DOI: 10.1029/1998ja900021] [Citation(s) in RCA: 146] [Impact Index Per Article: 5.8] [Reference Citation Analysis] [What about the content of this article? (0)] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/09/2022]
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Sulakhe PV, Vo XT, Phan TD, Morris TE. Phosphorylation of inhibitory subunit of troponin and phospholamban in rat cardiomyocytes: modulation by exposure of cardiomyocytes to hydroxyl radicals and sulfhydryl group reagents. Mol Cell Biochem 1997; 175:98-107. [PMID: 9350039] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [MESH Headings] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 02/05/2023]
Abstract
Myocytes were isolated from rat heart ventricles and then incubated with [32P]-sodium phosphate to label intracellular ATP stores. Incubations of the [32P]-labelled cardiomyocytes with a beta-adrenoceptor agonist isoproterenol (10 microM) and with a plant diterpene forskolin (100 microM) which directly stimulates adenylyl cyclase increased the phosphorylation of an inhibitory subunit of troponin (TN-I) and phospholamban (PLN). Brief exposure (1 min) of labelled myocytes to the hydroxyl radical generating system (H2O2 plus FeCl2) decreased markedly the stimulatory action of isoproterenol and forskolin on TN-I and PLN phosphorylation. Similar exposure of myocytes to 5-5'-dithiobis-nitrobenzoic acid (DTNB) a sulfhydryl oxidizing reagent exerted little inhibitory effect on the isoproterenol or forskolin stimulated TN-I and PLN phosphorylation. In contrast exposure of myocytes to low concentrations (< 50 microM) of N-ethylmaleimide (NEM) a sulfhydryl alkylating reagent augmented the stimulatory effect of isoproterenol on TN-I and PLN phosphorylation. The results further showed that brief treatment of myocytes to H2O2 plus FeCl2 markedly decreased isoproterenol-, but not forskolin-, stimulated cyclic AMP accumulation in the myocytes. The stimulatory action of NEM on the isoproterenol-stimulated TN-I and PLN phosphorylation appeared related to greater increase in the isoproterenol-stimulated cyclic AMP accumulation in the NEM-treated cardiomyocytes. The results are consistent with the postulate that hydroxyl radical exposure of cardiomyocytes blunts the beta-adrenoceptor-mediated stimulation of adenylyl cyclase leading to decreased phosphorylation of TN-I and PLN and imply that such alterations account in part the reported depressed rate of relaxation of the myocardium exposed to oxygen free radicals.
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Affiliation(s)
- P V Sulakhe
- Department of Physiology, College of Medicine, University of Saskatchewan, Saskatoon, Canada
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Davis TM, Li TA, Tran QB, Robertson K, Dyer JR, Phan TD, Meyer D, Beaman MH, Trinh KA. The hypothalamic-pituitary-adrenocortical axis in severe falciparum malaria: effects of cytokines. J Clin Endocrinol Metab 1997; 82:3029-33. [PMID: 9284738 DOI: 10.1210/jcem.82.9.4196] [Citation(s) in RCA: 8] [Impact Index Per Article: 0.3] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [MESH Headings] [Track Full Text] [Journal Information] [Submit a Manuscript] [Subscribe] [Scholar Register] [Indexed: 02/05/2023]
Abstract
Patients with malaria can have features of adrenal insufficiency. Because of the pathophysiological and clinical implications of an Addisonian state, the hypothalamic-pituitary-adrenocortical axis was assessed in nine Vietnamese adults with complicated malaria. A CRH test was performed on admission (in convalescence in five cases) and in six healthy controls. Basal plasma ACTH concentrations in the patients and controls were similar [median (range): 2.9 (0.2-9.7) vs. 3.5 (1.9-13.4) pmol/L, respectively; P > 0.1]. Serum cortisol levels were greater in the patients [882 (294-1682) vs. 190 (110-676) nmol/L; P < 0.01], but three (33%) had values within the control range. Basal serum corticosteroid-binding globulin concentrations were similar in patients and controls (P = 0.23). The post-CRH rise in plasma ACTH was attenuated in the patients [peak: 6.1 (0.9-23.2) vs. 14.5 (6.2-21.5) pmol/L in controls; P < 0.05]; basal and peak plasma ACTH correlated with plasma interleukin-6 in this group (rs > or = 0.60; P < or = 0.04). Serum cortisol responses to CRH were depressed in acute illness [peak 990 (394-1, 805) nmol/L or 10 (0-50%) above baseline vs. 500 (429-703) nmol/L or 160 (10-380%) in controls; P < 0.05]. The median estimated serum cortisol t1/2 was 4.6 h in the patients and 1.6 h in the controls. These data suggest that, relative to a normal stress response, primary and secondary adrenal insufficiency can occur in severe malaria but may be attenuated by increased circulating interleukin-6 concentrations and impaired cortisol metabolism. The benefits of stress-dose corticosteroid replacement are unknown but could be considered in hypoglycemic patients or those with a serum cortisol within or below the reference range.
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Affiliation(s)
- T M Davis
- University of Western Australia, Department of Medicine, Fremantle Hospital, Australia.
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Qu Y, Torchia J, Phan TD, Wu PH, Sen AK. Endogenous substrates of rat heart protein kinase C type I, II, and III isozymic forms in cardiac sarcolemma. Biochem Cell Biol 1992; 70:81-5. [PMID: 1581036 DOI: 10.1139/o92-012] [Citation(s) in RCA: 4] [Impact Index Per Article: 0.1] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 12/27/2022] Open
Abstract
The endogenous substrate proteins of rat cardiac protein kinase C type I, II, and III isozymic forms were studied in rat cardiac sarcolemma. The 19-, 21-, 29-, 35-, and 95-kDa proteins were phosphorylated by both types II and III, but not type I. The extent of phosphorylation by individual protein kinase C isozymic forms was additive and equal to the extent of phosphorylation observed when a mixture of isozymic forms was employed. The extent of phosphorylation of the 21-kDa protein by type III was much higher than that by type II. These results suggest that the protein kinase C isozymes have preferences for specific endogenous substrate proteins. The phosphorylation of these endogenous substrate proteins by protein kinase C isozymes probably plays a role in cardiac cell functions.
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Affiliation(s)
- Y Qu
- Department of Pharmacology, Faculty of Medicine, University of Toronto, Ont., Canada
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Abstract
A calcium-sensitive, phospholipid-dependent protein kinase (protein kinase C) and its three isozymes were purified from rat heart cytosolic fractions utilizing a rapid purification method. The purified protein kinase C enzyme showed a single polypeptide band of 80 KDa on SDS-polyacrylamide gel electrophoresis, and was totally dependent on the presence of Ca2+ and phospholipid for activity. Diacylglycerol was also found to stimulate enzymatic activity. Autophosphorylation of the purified PKC showed an 80 KDa polypeptide. The identity of the purified protein was also verified with monoclonal antibodies specific for PKC. Further fractionation of the purified PKC on a hydroxylapatite column yielded three distinct peaks of enzyme activity, corresponding to type I, II and III based on similar chromatographic behaviour as the rat brain enzyme. All three forms were entirely Ca2+ and phosphatidylserine dependent. Type II was found to be the most abundant. Type I was found to be highly unstable. PKC activity studies demonstrate that types II and III isozymic forms are different with respect to their sensitivity to Ca2+.
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Affiliation(s)
- Y Qu
- Department of Pharmacology, Faculty of Medicine, University of Toronto, Canada
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