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Fixing the reference frame for PPMXL proper motions using extragalactic sources

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Research in Astronomy and Astrophysics 2015年第6期15卷 849-859页

作者： Kathleen Grabowski j.ffrey L. carlin Heidi j. Newberg Timothy C. Beers Li Chen Li-Cai Deng carl j. grillmair Puragra Guhathakurta j.n-Liang Hou Yong-Hui Hou Se'bastien Le'pine Chao Liu Xiao-Wei Liu A-Li Luo Martin C. Smith Brian Yanny Hao-Tong Zhang Yong Zhang Zheng Zheng Department of Physics Applied Physics and Astronomy Rensselaer Polytechnic Institute 110 8th Street Troy NY 12180 USA Department of Physics and j.NA: j.int Institute for Nuclear Astrophysics University of Notre Dame 225 Nieuwland Science Hall Notre Dame IN 46556 USA Shanghai Astronomical Observatory Key Lab of Optical Astronomy National Astronomical Observatories Chinese Academy of Sciences Spitzer Science Center 1200 E. California Blvd. Pasadena CA 91125 USA UCO/Lick Observatory Department of Astronomy and Astrophysics University of CaliforniaSanta Cruz CA 95064 USA Nanj.ng Institute of Astronomical Optics & Technology National Astronomical ObservatoriesChinese Academy of Sciences Department of Physics and Astronomy Georgia State University 25 Park Place Suite 605Atlanta GA 30303 USA Kavli Institute for Astronomy and Astrophysics Peking University Department of Astronomy Peking University Fermi National Accelerator Laboratory P.O. Box 500 Batavia IL 60510 USA Department of Physics and Astronomy University of Utah

We quantify and correct systematic errors in PPMXL proper motions using extragalactic sources from the first two LAMOST data releases and the Vbron-Cetty ＆ Vebron Catalog of Quasars. Although the maj.rity of the sources are from the Veron catalog, LAMOST makes important contributions in regions that are not well-sampled by previous catalogs, particularly at low Galactic latitudes and in the south Galactic cap. We show that quasars in PPMXL have measurable and significant proper motions, which reflect the systematic zero-point offsets present in the catalog. We confirm the global proper motion shifts seen by Wu et al., and additionally find smaller-scale fluctuations of the QSO-derived corrections to an absolute frame. We average the proper motions of 158 106 extragalactic obj.cts in bins of 3° ×3° and present a table of proper motion corrections.

关键词： catalogs -- proper motions -- surveys LAMOST

LAMOST Experiment for Galactic Understanding and Exploration (LEGUE)——The survey's science plan

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Research in Astronomy and Astrophysics 2012年第7期12卷 735-754页

作者： Li-Cai Deng Heidi j. Newberg Chao Liu j.ffrey L. carlin Timothy C. Beers Li Chen Hsu-Tai Lee carl j. grillmair Puragra Guhathakurta] Zhan-Wen Han j.n-Liang Hou Sebastien Lepine j.ng Li Xiao-Wei Liu Kai-Ke Pan j. A. Sellwood Bo Wang Hong-Chi Wang Fan Yang Brian Yanny Hao-Tong Zhang Yue-Yang Zhang Zheng Zheng Zi Zhu Key Lab for Optical Astronomy National Astronomical Observatories Chinese Academy of Sciences Beijing 100012 China licai@*** Department of Physics Applied Physics and Astronomy Rensselaer Polytechnic Institute 1108th Street Troy NY 12180 USA National Optical Astronomy Observatory Tucson AZ 85719 USA Shanghai Astronomical Observatory Chinese Academy of Sciences Shanghai 200030 China Institute of Astronomy and Astrophysics Academia Sinica EO. Box 23-141 Taipei 106 China University of Heidelberg Landessternwarte K6nigstuhl 12 D-69117 Heidelberg Germany Spitzer Science Center 1200 E. California Blvd. Pasadena CA 91125 USA Department of Astronomy and Astrophysics University of California Santa Cruz 1156 HighStreet Santa Cruz CA 95064 USA Yunnan Astronomical Observatory Chinese Academy of Sciences Kunming 650011 China American Museum of Natural History Central Park West at 79th Street New York NY 10024USA School of Physics and Electronic Information China West Normal University Nanchong637000 China ' Department of Astronomy & Kavli Institute of Astronomy and Astrophysics Peking University Beijing 100871 China Apache Point Observatory PO Box 59 Sunspot NM 88349 USA Department of Physics and Astronomy Rutgers University 136 Frelinghuysen RoadPiscataway NJ 08854-8019 USA Purple Mountain Observatory Chinese Academy of Sciences Nanjing 210008 China Fermi National Accelerator Laboratory Batavia IL 60510 USA Department of Physics and Astronomy University of Utah Salt Lake City UT 84112 USA School of Astronomy and Space Science Nanjing University Nanjing 210008 China

We describe the current plans for a spectroscopic survey of millions of stars in the Milky Way galaxy using the Guo Shou j.ng Telescope （GSj., formerly calledthe Large sky Area Multi-Obj.ct fiber Spectroscopic Telescope -- LAMOST）. The survey will obtain spectra for 2.5 million stars brighter than r 〈 19 during dark/grey time, and 5 million stars brighter than r 〈 17 or j.〈 16 on nights that are moonlit or have low transparency. The survey will begin in the fall of 2012, and will run for at least four years. The telescope＇s design constrains the optimal declination range for observations to 10~ 〈 di 〈 50~, and site conditions lead to an emphasis on stars in the direction of the Galactic anticenter. The survey is divided into three parts with different target selection strategies： disk, anticenter, and spheroid. The resulting dataset will be used to study the merger history of the Milky Way, the substructure and evolution of the disks, the nature of the first generation of stars through identification of the lowest metallicity stars, and star formation through study of open clusters and OB associations. Detailed design of the LAMOST Experiment for Galactic Understanding and Exploration （LEGUE） survey will be completed in summer 2012, after a review of the results of the pilot survey.

关键词： techniques: spectroscopic -Galaxy: structure - Galaxy: evolution -Galaxy: kinematics and dynamics -- Galaxy: disk -- Galaxy: halo -- spectroscopy

An algorithm for preferential selection of spectroscopic targets in LEGUE

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Research in Astronomy and Astrophysics 2012年第7期12卷 755-771页

作者： j.ffrey L. carlin Sebastien Lepine Heidi j. Newberg Li-Cai Deng Timothy C. Beers Yu-Qin Chen Norbert Christlie Xiao-Ting Fu Shuang Gao carl j. grillmair PuragraGuhathakurta Zhan-Wen Han j.n-Liang Hou Hsu-Tai Lee j.ng Li Chao Liu Xiao-Wei Liu Kai-Ke Pan j. A. Sellwood Hong-Chi Wang Fan Yang Brian Yanny Yue-Yang Zhan Zheng Zheng Zi Zhu Department of Physics Applied Physics and Astronomy Rensselaer Polytechnic Institute 110 8th Street Troy NY 12180 USA carlij.rpi.edu Department of Astrophysics American Museum of Natural History Central Park West at 79thStreet New York NY 10024 USA City University of New York 365 Fifth Avenue New York NY 10016 USA National Astronomical Observatories Chinese Academy of Sciences Beijing 100012 China National Optical Astronomy Observatory Tucson AZ 85719 USA Center for Astronomy University of Heidelberg Landesstemwarte Ktinigstuhl 12 D-69117Heidelberg Germany Spitzer Science Center 1200 E. California Blvd. Pasadena CA 91125 USA j.O/Lick Observatory Department of Astronomy and Astrophysics University of CaliforniaSanta Cruz CA 95064 USA Yunnan Astronomical Observatory Chinese Academy of Sciences Kunming 650011 China Shanghai Astronomical Observatory Chinese Academy of Sciences Shanglai 200030 China Institute of Astronomy and Astrophysics Academia Sinica EO. Box 23-141 Taipei 106 China Department of Astronomy & Kavli institute of Astronomy and Astrophysics Peking UniversityBeijing 100875 China Apache Point Observatory PO Box 59 Sunspot NM 88349 USA Department of Physics and Astronomy Rutgers University 136 Frelinghuysen RoadPiscataway NJ 08854-8019 USA Purple Mountain Observatory Chinese Academy of Sciences Nanjing 210008 China Fermi National Accelerator Laboratory EO. Box 500 Batavia IL 60510 USA Department of Physics and Astronomy University of Utah Salt Lake City UT 84112 USA Department of Astronomy Nanjing University Nanjing 210011 China

We describe a general target selection algorithm that is applicable to any survey in which the number of available candidates is much larger than the number of obj.cts to be observed. This routine aims to achieve a balance between a smoothly- varying, well-understood selection function and the desire to preferentially select cer- tain types of targets. Some target-selection examples are shown that illustrate differentpossibilities of emphasis functions. Although it is generally applicable, the algorithm was developed specifically for the LAMOST Experiment for Galactic Understanding and Exploration （LEGUE） survey that will be carried out using the Chinese Guo Shou j.ng Telescope. In particular, this algorithm was designed for the portion of LEGUE targeting the Galactic halo, in which we attempt to balance a variety of science goals that require stars at fainter magnitudes than can be completely sampled by LAMOST. This algorithm has been implemented for the halo portion of the LAMOST pilot sur- vey, which began in October 2011.

关键词： surveys: LAMOST -- Galaxy: halo -- techniques: spectroscopic

miniSCIDOM: a scintillator-based tomograph for volumetric dose reconstruction of single laser-driven proton bunches

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High Power Laser Science and Engineering 2024年第2期12卷 41-50页

作者： A.Corvino M.Reimold E.Beyreuther F.-E.Brack F.Kroll j.Pawelke j.D.Schilz M.Schneider U.Schramm M.E.P.Umlandt K.Zeil T.Ziegler j.Metzkes-Ng Helmholtz-Zentrum Dresden–Rossendorf DresdenGermany Technische Universität Dresden DresdenGermany OncoRay–National Center for Radiation Research in Oncology Faculty of Medicine and University Hospital Carl Gustav CarusTUD Dresden University of TechnologyHelmholtz-Zentrum Dresden–RossendorfDresdenGermany Current affiliation:Institut Curie UniversitéPSLCNRS UMR3347OrsayFrance Current affiliation:Universitätsklinikum Freiburg FreiburgGermany

Laser plasma accelerators(LPAs)enable the generation of intense and short proton bunches on a micrometre scale,thus offering new experimental capabilities to research fields such as ultra-high dose rate radiobiology or material *** spectrally broadband,laser-accelerated proton bunches allow for tailored volumetric dose deposition in a sample via single bunches to excite or probe specific sample *** rising number of such experiments indicates a need for diagnostics providing spatially resolved characterization of dose distributions with volumes of approximately 1 cm^(3) for single proton bunches to allow for fast online *** we present the scintillator-based miniSCIDOM detector for online single-bunch tomographic reconstruction of dose distributions in volumes of up to approximately 1 cm^(3).The detector achieves a spatial resolution below 500μm and a sensitivity of 100 *** detector performance is tested at a proton therapy cyclotron and an LPA proton *** experiments’primary focus is the characterization of the scintillator’s ionization quenching behaviour.

关键词： beam monitoring detectors laser-driven proton beams scintillator-based diagnostics ultra-high dose rate

Out-of-core clustering of volumetric datasets

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j.urnal of Zhej.ang University-Science A(Applied Physics & Engineering) 2006年第7期7卷 1134-1140页

作者： GRANBERG carl j. Department of Computing Curtin University of Technology Perth Australia

In this paper we present a novel method for dividing and clustering large volumetric scalar out-of-core datasets. This work is based on the Ordered Cluster Binary Tree (OCBT) structure created using a top-down or divisive clustering method. The OCBT structure allows fast and efficient sub volume queries to be made in combination with level of detail (LOD) queries of the tree. The initial partitioning of the large out-of-core dataset is done by using non-axis aligned planes calculated using Principal Component Analysis (PCA). A hybrid OCBT structure is also proposed where an in-core cluster binary tree is combined with a large out-of-core file.

关键词：聚类混合翻译科学可视化 OCBT 数据集

Supramolecular Self-assembly Formed from Cucurbit[8]uril and p-Hydroxybenzoic Acid

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Chemical Research in Chinese Universities 2023年第6期39卷 1058-1063页

作者： WANG Chenghui YU Zhichao BAI Qinghong PAN Dingwu PRIOR Timothy j.TAO Zhu REDSHAW carl XIAO Xin Key Laboratory of Macrocyclic and Supramolecular Chemistry of Guizhou Province Guizhou UniversityGuiyang 550025P.R.China Chemistry School of Natural SciencesUniversity of HullHull HU67RXUK

The binding behavior of cucurbit[8]uril(Q[8])and p-hydroxybenzoic acid(p-HBA)has been investigated using ^(1)H NMR titration experiments,UV-Vis absorption,isothermal titration calorimetry(ITC),and X-ray *** revealed that the Q[8]can accommodate two p-HBA molecules to form a 1:2 host-guest inclusion complex in solution,namely(p-HBA)2@Q[8].From a poorly scattering crystal,we were able to identify two symmetry unique Q[8]rings,but with different p-HBA *** structure can be represented as Q[8]+1.5 p-HBA,which gives Q[8]@(p-HBA)2∙Q[8]@p-HBA as the structural *** supramolecular structure was screened for its ability to capture *** experimental results showed that the adsorption efficiency of the supramolecular organic framework material for iodine capture was 43.8%,with an equilibrium adsorption capacity of 223.3 mg/g.

关键词： Supramolecular self-assembly Cucurbituril p-Hydroxybenzoic acid

Evidence for Cerebral Microvascular Inj.ry in Head Trauma Involving Infants and Young Children

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j.urnal of Forensic Science and Medicine 2022年第2期8卷 41-45页

作者： Rudolph j.Castellani Ashley Rose Scholl carl j.Schmidt Department of Pathology Northwestern University Feinberg School of MedicineChicagoIllinoisUSA Department of Pathology Duke University School of MedicineDurhamNorth CarolinaUSA Department of Pathology Wayne County Medical Examiner's OfficeDetroitMichiganUSA Department of Pathology University of MichiganAnn ArborMichiganUSA

Background:The pathophysiology of lethal head trauma in infants and young children involves repetitive rotational forces of sufficient magnitude to produce subdural hemorrhage and brain swelling,which leads to considerable morbidity and *** precise mechanism for brain swelling is *** and Methods:We examined cerebral tissue from ten pediatric deaths due to blunt force trauma,along with seven control infants who asphyxiated in unsafe sleep *** assess the competence of the blood-brain barrier,we performed immunohistochemical stains for albumin and immunoglobulin G(IgG).Results:IgG and albumin were increased in subpial and superficial perivascular tissue in those cases due to blunt force trauma,and in particular,the blunt force trauma associated with subdural *** included two deaths at the scene without hospital survival ***:Our findings suggest disruption of the blood-brain barrier with vasogenic edema as an early event in head trauma involving young children upstream of global ischemic brain *** hypothesize that mechanical inj.ry to the cortical vasculature results in vasogenic edema by oncotic(increased plasma proteins in the cortical interstitium)and hydrostatic(increased capillary pressure)mechanisms,with subsequent cortical *** may explain why ischemic sequelae appear to occur in head trauma involving young children,regardless of whether anoxia,hypotension,or cardiac arrest complicate the disease course and may in part underlie the high morbidity and mortality of head trauma in early childhood.

关键词： Edema pediatric head trauma subdural hematoma traumatic brain inj.ry

NUMERICAL SIMULATION OF THE XZ TAURI SUPERSONIC ASTROPHYSICAL j.T

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Acta Mathematica Scientia 2009年第6期29卷 1677-1683页

作者： carl L. Gardner Steven j. Dwyer School of Mathematical and Statistical Sciences Arizona State University Tempe AZ 85287 USA

Computational gas dynamical simulations using the WENO-LF method are applied to modeling the high Mach number astrophysical j.t XZ Tauri, including the effects of radiative cooling. Mach 55 simulations of the pulsed proto-j.t are presented and analyzed in terms of interacting nonlinear waves： terminal Mach disks, bow shocks, and Meshkov-Richtmyer instabilities of the leading j.t contact boundary.

关键词： astrophysical j.ts ENO. method gas dynamics

Hierarchically Structured Nanocomposites via a“Systems Materials Science”Approach

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Accounts of Materials Research 2022年第12期3卷 1248-1259页

作者： Rebecca L.Li carl j.Thrasher Theodore Hueckel Robert j.Macfarlane Department of Materials Science and Engineering Massachusetts Institute of TechnologyCambridgeMassachusetts 02139United States Department of Mechanical Engineering Massachusetts Institute of TechnologyCambridgeMassachusetts 02139United States

CONSPECTUS:Nanocomposite materials can achieve desirable characteristics otherwise unavailable to single component systems,making them attractive platforms to precisely modulate a material’s mechanical,electromagnetic,thermal,and optical *** these properties are often dependent on the organization of constituent materials j.st as much as their relative composition,intentionally programming composite properties requires hierarchical structural control across many length ***,the fundamental forces governing the atomic,molecular,nanoscale,microscale,and macroscale composition and structure of a material are all interlinked,and thus must be manipulated simultaneously to properly create ideal designer materials.

关键词： properties composite composites