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Correlations in Scattered X-Ray Laser Pulses Reveal Nanoscale Structural Features of Viruses

Physical Review Letters 2017年第15期119卷 158102-158102页

作者： Ruslan P. Kurta Jeffrey J. Donatelli Chun Hong Yoon Peter Berntsen Johan Bielecki Benedikt J. Daurer Hasan DeMirci Petra Fromme Max Felix Hantke Filipe R. N. C. Maia Anna Munke Carl Nettelblad Kanupriya Pande Hemanth K. N. Reddy Jonas A. Sellberg Raymond G. Sierra Martin Svenda Gijs van der Schot Ivan A. Vartanyants Garth J. Williams P. Lourdu Xavier Andrew Aquila Peter H. Zwart Adrian P. Mancuso European XFEL GmbH Holzkoppel 4 D-22869 Schenefeld Germany Mathematics Department Lawrence Berkeley National Laboratory 1 Cyclotron Road Berkeley California 94720 USA Center for Advanced Mathematics for Energy Research Applications 1 Cyclotron Road Berkeley California 94720 USA Linac Coherent Light Source SLAC National Accelerator Laboratory 2575 Sand Hill Road Menlo Park California 94025 USA Australian Research Council Centre of Excellence in Advanced Molecular Imaging La Trobe Institute for Molecular Science La Trobe University Melbourne 3086 Australia Laboratory of Molecular Biophysics Department of Cell and Molecular Biology Uppsala University SE-751 24 Uppsala Sweden Biosciences Division SLAC National Accelerator Laboratory 2575 Sand Hill Road Menlo Park California 94025 USA Stanford PULSE Institute SLAC National Accelerator Laboratory 2575 Sand Hill Road Menlo Park California 94025 USA Biodesign Center for Applied Structural Discovery and School of Molecular Sciences Arizona State University Tempe Arizona 85287-1604 USA NERSC Lawrence Berkeley National Laboratory Berkeley California 94720 USA Division of Scientific Computing Science for Life Laboratory Department of Information Technology Uppsala University SE-751 05 Uppsala Sweden Molecular Biophysics and Integrated Bioimaging Lawrence Berkeley National Laboratory 1 Cyclotron Road Berkeley California 94720 USA Biomedical and X-Ray Physics Department of Applied Physics AlbaNova University Center KTH Royal Institute of Technology Stockholm SE-106 91 Sweden Deutsches Elektronen-Synchrotron DESY Notkestraße 85 D-22607 Hamburg Germany National Research Nuclear University MEPhI (Moscow Engineering Physics Institute) Kashirskoe shosse 31 115409 Moscow Russia NSLS-II Brookhaven National Laboratory P.O. Box 5000 Upton New York 11973 USA Center for Free-Electron Laser Science Deutsches Elektronen-Synchrotron DESY Notkestraße 85 22607 Hamburg Germany Max-Planck Institute for the Structure and Dy

We use extremely bright and ultrashort pulses from an x-ray free-electron laser (XFEL) to measure correlations in x rays scattered from individual bioparticles. This allows us to go beyond the traditional crystallography and single-particle imaging approaches for structure investigations. We employ angular correlations to recover the three-dimensional (3D) structure of nanoscale viruses from x-ray diffraction data measured at the Linac Coherent Light Source. Correlations provide us with a comprehensive structural fingerprint of a 3D virus, which we use both for model-based and ab initio structure recovery. The analyses reveal a clear indication that the structure of the viruses deviates from the expected perfect icosahedral symmetry. Our results anticipate exciting opportunities for XFEL studies of the structure and dynamics of nanoscale objects by means of angular correlations.

关键词： Biomolecular structure Viruses Coherent X-ray scattering Femtosecond laser irradiation X-ray imaging

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Search for the lepton flavor violating decay τ →3µ in proton-proton collisions at √s = 13 TeV

arXiv

引用

arXiv 2020年

作者： Sirunyan, A.M. Tumasyan, A. Adam, W. Bergauer, T. Dragicevic, M. Erö, J. Escalante Del Valle, A. Frühwirth, R. Jeitler, M. Krammer, N. Lechner, L. Liko, D. Madlener, T. Mikulec, I. Pitters, F.M. Rad, N. Schieck, J. Schöfbeck, R. Spanring, M. Templ, S. Waltenberger, W. Wulz, C.-E. Zarucki, M. Chekhovsky, V. Litomin, A. Makarenko, V. Suarez Gonzalez, J. Darwish, M.R. de Wolf, E.A. Di Croce, D. Janssen, X. Kello, T. Lelek, A. Pieters, M. Rejeb Sfar, H. van Haevermaet, H. van Mechelen, P. van Putte, S. van Remortel, N. Blekman, F. Bols, E.S. Chhibra, S.S. D’Hondt, J. de Clercq, J. Lontkovskyi, D. Lowette, S. Marchesini, I. Moortgat, S. Morton, A. Python, Q. Tavernier, S. van Doninck, W. van Mulders, P. Beghin, D. Bilin, B. Clerbaux, B. de Lentdecker, G. Dorney, B. Favart, L. Grebenyuk, A. Kalsi, A.K. Makarenko, I. Moureaux, L. Pétré, L. Popov, A. Postiau, N. Starling, E. Thomas, L. Vander Velde, C. Vanlaer, P. Vannerom, D. Wezenbeek, L. Cornelis, T. Dobur, D. Gruchala, M. Khvastunov, I. Niedziela, M. Roskas, C. Skovpen, K. Tytgat, M. Verbeke, W. Vermassen, B. Vit, M. Bruno, G. Bury, F. Caputo, C. David, P. Delaere, C. Delcourt, M. Donertas, I.S. Giammanco, A. Lemaitre, V. Mondal, K. Prisciandaro, J. Taliercio, A. Teklishyn, M. Vischia, P. Wertz, S. Wuyckens, S. Alves, G.A. Hensel, C. Moraes, A. Aldá Júnior, W.L. Belchior Batista Das Chagas, E. Brandao Malbouisson, H. Carvalho, W. Chinellato, J. Coelho, E. da Costa, E.M. da Silveira, G.G. de Jesus Damiao, D. Fonseca De Souza, S. Martins, J. Matos Figueiredo, D. Medina Jaime, M. Mora Herrera, C. Mundim, L. Nogima, H. Rebello Teles, P. Sanchez Rosas, L.J. Santoro, A. Silva Do Amaral, S.M. Sznajder, A. Thiel, M. Torres Da Silva De Araujo, F. Vilela Pereira, A. Bernardes, C.A. Calligaris, L. Fernandez Perez Tomei, T.R. Gregores, E.M. Lemos, D.S. Mercadante, P.G. Novaes, S.F. Padula, Sandra S. Aleksandrov, A. Antchev, G. Atanasov, I. Hadjiiska, R. Iaydjiev, P. Misheva, M. Rodozov, M. Shopova, M. Sultanov, G. Bonchev, M. Dimitrov, A. Ivanov, T. Litov, L. Pavlov, B. Yerevan Physics Institute Yerevan Armenia Institut für Hochenergiephysik Wien Austria Institute for Nuclear Problems Minsk Belarus Universiteit Antwerpen Antwerpen Belgium Vrije Universiteit Brussel Brussel Belgium Université Libre de Bruxelles Bruxelles Belgium Ghent University Ghent Belgium Université Catholique de Louvain Louvain-la-Neuve Belgium Centro Brasileiro de Pesquisas Fisicas Rio de Janeiro Brazil Universidade do Estado do Rio de Janeiro Rio de Janeiro Brazil Universidade Estadual Paulista São Paulo Brazil Universidade Federal do ABC São Paulo Brazil Institute for Nuclear Research and Nuclear Energy Bulgarian Academy of Sciences Sofia Bulgaria University of Sofia Sofia Bulgaria Beihang University Beijing China Department of Physics Tsinghua University Beijing China Institute of High Energy Physics Beijing China State Key Laboratory of Nuclear Physics and Technology Peking University Beijing China Sun Yat-Sen University Guangzhou China Institute of Modern Physics and Key Laboratory of Nuclear Physics and Ion-beam Application MOE Fudan University Shanghai China Zhejiang University Hangzhou China Universidad de Los Andes Bogota Colombia Universidad de Antioquia Medellin Colombia University of Split Faculty of Electrical Engineering Mechanical Engineering and Naval Architecture Split Croatia University of Split Faculty of Science Split Croatia Institute Rudjer Boskovic Zagreb Croatia University of Cyprus Nicosia Cyprus Charles University Prague Czech Republic Escuela Politecnica Nacional Quito Ecuador Universidad San Francisco de Quito Quito Ecuador Academy of Scientific Research and Technology of the Arab Republic of Egypt Egyptian Network of High Energy Physics Cairo Egypt Center for High Energy Physics CHEP-FU Fayoum University El-Fayoum Egypt National Institute of Chemical Physics and Biophysics Tallinn Estonia Department of Physics University of Helsinki Helsinki Finland Helsinki Institute of Physics Helsinki Finland La

Results are reported from a search for the lepton flavor violating decay τ → 3µ in proton-proton collisions at √s = 13 TeV. The data sample corresponds to an integrated luminosity of 33.2 fb−1 recorded by the CMS experiment at the LHC in 2016. The search exploits τ leptons produced in both W boson and heavy-flavor hadron decays. No significant excess above the expected background is observed. An upper limit on the branching fraction B(τ → 3µ) of 8.0 × 10−8 at 90% confidence level is obtained, with an expected upper limit of 6.9 × 10−8 Copyright © 2020, The Authors. All rights reserved.

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A search for bottom-type, vector-like quark pair production in a fully hadronic final state in proton-proton collisions at √s = 13 TeV

arXiv

引用

arXiv 2020年

A search is described for the production of a pair of bottom-type vector-like quarks (VLQs), each decaying into a b or b quark and either a Higgs or a Z boson, with a mass greater than 1000 GeV. The analysis is based on data from proton-proton collisions at a 13 TeV center-of-mass energy recorded at the CERN LHC, corresponding to a total integrated luminosity of 137 fb−1. As the predominant decay modes of the Higgs and Z bosons are to a pair of quarks, the analysis focuses on final states consisting of jets resulting from the six quarks produced in the events. Since the two jets produced in the decay of a highly Lorentz-boosted Higgs or Z boson can merge to form a single jet, nine independent analyses are performed, categorized by the number of observed jets and the reconstructed event mode. No signal in excess of the expected background is observed. Lower limits are set on the VLQ mass at 95% confidence level equal to 1570 GeV in the case where the VLQ decays exclusively to a b quark and a Higgs boson, 1390 GeV for when it decays exclusively to a b quark and a Z boson, and 1450 GeV for when it decays equally in these two modes. These limits represent significant improvements over the previously published VLQ limits. Copyright © 2020, The Authors. All rights reserved.

关键词： Bosons

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Cloud computing Platform and Big Data Service for Incubator Cluster

Cloud Computing Platform and Big Data Service for Incubator ...

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2016年IEEE/INFORMS服务运筹、物流与信息化国际会议

作者： Gang Xiong Chi Zhang Tongkai Ji Banji Guan Aobing Sun Yuexiang Hu Timo R.Nyberg Dongguan Research Institute of CASIA Cloud Computing CenterChinese Academy of Sciences The State Key Laboratory of Management and Control for Complex Systems Institute of AutomationChinese Academy of Sciences School of Economic and Management Beijing University of Chemical Technology Department of Industrial Engineering and Management School of Sciences Aalto University

Hundreds of incubators get birthed worldwide every day, and many new ICT technologies developed continuously, like cloud computing and big data. Therefore, it's possible and necessary to develop a cloud computing platform that gathering a variety of data and resources information needed by thousands of incubators and millions of incubated enterprises. In this paper, after comparing three different countries incubator's management procedure, we mainly talk about the way to design a cloud-based incubator platform including its architecture, main functions, and the interface. We assume that the platform can gather and share a variety of information and resource, like money, human resource, equipment, office place and so on. So the platform is beneficial for the incubated enterprises, incubators, and the government. For example, the platform can provide individual services through big data technology. The platform can analysis the situation of incubators and warn the companies in dangerous condition with the history big data. Finally, this paper describes the use case of cloud-based incubator platform for Guangdong Province.

关键词： business incubator cluster open innovation cloud computing platform crowdsourcing big data service

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Measurements of the W boson rapidity, helicity, double-differential cross sections, and charge asymmetry in pp collisions at √s = 13 TeV

arXiv

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arXiv 2020年

The differential cross section and charge asymmetry for inclusive W boson production at √s = 13 TeV is measured for the two transverse polarization states as a function of the W boson absolute rapidity. The measurement uses events in which a W boson decays to a neutrino and either a muon or an electron. The data sample of proton-proton collisions recorded with the CMS detector at the LHC in 2016 corresponds to an integrated luminosity of 35.9 fb−1. The differential cross section and its value normalized to the total inclusive W boson production cross section are measured over the rapidity range |yW| 2σ/dpT`d|η`|, and the charge asymmetry are measured as functions of the charged lepton transverse momentum and pseudorapidity. The precision of these measurements is used to constrain the parton distribution functions of the proton using the next-to-leading order NNPDF3.0 set. Copyright © 2020, The Authors. All rights reserved.

关键词： Distribution functions

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Search for decays of the 125 GeV Higgs boson into a Z boson and a ρ or φ meson

arXiv

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arXiv 2020年

Decays of the 125 GeV Higgs boson into a Z boson and a ρ0(770) or φ(1020) meson are searched for using proton-proton collision data collected by the CMS experiment at the LHC at √s = 13 TeV. The analysed data set corresponds to an integrated luminosity of 137 fb−1. Events are selected in which the Z boson decays into a pair of electrons or a pair of muons, and the ρ and φ mesons decay into pairs of pions and kaons, respectively. No significant excess above the background model is observed. As different polarization states are possible for the decay products of the Z boson and ρ or φ mesons, affecting the signal acceptance, scenarios in which the decays are longitudinally or transversely polarized are considered. Upper limits at the 95% confidence level on the Higgs boson branching fractions into Zρ and Zφ are determined to be 1.04–1.31% and 0.31–0.40%, respectively, where the ranges reflect the considered polarization scenarios;these values are 740–940 and 730–950 times larger than the respective standard model expectations. These results constitute the first experimental limits on the two decay channels. Copyright © 2020, The Authors. All rights reserved.

关键词： Bosons

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A measurement of the Higgs boson mass in the diphoton decay channel

arXiv

引用

arXiv 2020年

A measurement of the mass of the Higgs boson in the diphoton decay channel is presented. This analysis is based on 35.9 fb−1 of proton-proton collision data collected during the 2016 LHC running period, with the CMS detector at a center-of-mass energy of 13 TeV. A refined detector calibration and new analysis techniques have been used to improve the precision of this measurement. The Higgs boson mass is measured to be mH = 125.78 ± 0.26 GeV. This is combined with a measurement of mH already performed in the H → ZZ → 4` decay channel using the same data set, giving mH = 125.46 ± 0.16 GeV. This result, when further combined with an earlier measurement of mH using data collected in 2011 and 2012 with the CMS detector, gives a value for the Higgs boson mass of mH = 125.38 ± 0.14 GeV. This is currently the most precise measurement of the mass of the Higgs boson. Copyright © 2020, The Authors. All rights reserved.

关键词： Bosons

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A software trustworthiness measure based on the decompositions of trustworthy attributes and its validation

A software trustworthiness measure based on the decompositio...

引用

International Conference on Industrial engineering, Management Science and Applications, ICIMSA 2015

作者： Tao, Hongwei Chen, Yixiang Pang, Jianmin State Key Laboratory of Mathematical Engineering and Advanced Computing Zhengzhou45002 China MoE Engineering Center for Software/Hardware Co-Design Technology and Application East China Normal University Shanghai200062 China

ISBN: (纸本)9783662471999

There exist many software trustworthiness measures based on the decompositions of attributes. However, few of them are concerned with using more rigorous approaches to measure software trustworthiness and carrying out the theoretical validation of measures. Axiomatic approaches formalize the empirical understanding of a software attribute through the definition of a set of desirable software measure properties. It can provide precise and formal terms for the quantification of software attributes. We once used axiomatic approaches to measure software trustworthiness based on multi-dimensional attributes, in this paper, based on previous works, we apply axiomatic approaches to measure software trustworthiness based on the decompositions of attributes, propose the desirable properties of software trustworthiness measures based on the decompositions of attributes, present a software trustworthiness measure and validate this measure from the theory by proving that it complies with the set of properties. Compared with the popular software trustworthiness measures, this measure can evaluate software trustworthiness better in view of our properties. © Springer-Verlag Berlin Heidelberg 2015.

关键词： Computers

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Micro-structure characteristics of undisturbed expansive soil under the wetting-drying effect

引用

International Symposium on Geomechanics from Micro to Macro, IS-Cambridge 2014

作者： Wang, Y. Kong, L.W. Wang, Y.L. Liu, T. State Key Laboratory of Geomechanics and Geotechnical Engineering Institute of Rock and Soil Mechanics Chinese Academy of Sciences Wuhan China Key Laboratory of Geotechnical Mechanics and Engineering Ministry OfWater Resources Yangtze River Scientific Research Institute Wuhan China School of Civil Engineering and Architecture Wuhan University of Tehnology Wuhan China

ISBN: (纸本)9781138027077

The drying-wetting process of expansive soil caused by atmospheric action is the most important factor that contributes to the degradation of the soil's engineering properties. Studies on the evolution law of the microstructure of undisturbed expansive soil are conducted under the wetting-drying process. The drying-wetting effect of expansive soil caused by atmospheric action is simulated in a constant temperature and humidity box, and then some tests of mercury intrusion porosimetry and scanning electron microscopy are carried out. Results show that the influence of wetting and drying on the characteristics of the expansive soil microstructure is significant;the manner by which the microstructures adjust and change differs significantly during the drying or wetting process. Structures with the large pore diameter generate a significant effect. The drying process causes damage more easily to the primary macro pore structure or micro fractures of expansive soil compared with the wetting process;however, the wetting process amplifies the damage and results in uniform pore size distribution. © 2015 Taylor & Francis Group.

关键词： Microstructure

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Data layout transformation for structure vectorization on SIMD architectures

Data layout transformation for structure vectorization on SI...

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ACIS International Conference on Software engineering, Artificial Intelligence, Networking, and Parallel/Distributed computing (SNPD)

作者： Peng-yuan Li Qing-hua Zhang Rong-cai Zhao Hai-ning Yu State Key Laboratory of Mathematical Engineering and Advanced Computing Zhengzhou China

Structure references are commonly-used at the core of applications in a multitude of domains such as image processing, signal processing, especially the scientific and engineering applications. SIMD instruction sets, as SSE, AVX, AltiVec and 3DNow, provide a promising and widely available avenue for enhancing performance on modern processors. However existing memory accessing shackles limit the achieved performance for structure reference on modern SIMD architectures. In this paper, we propose a novel data layout transformation technology that addresses the accessing obstacles, along with a static analysis technique for detecting the legal loops in where this transformation is suitable. And this approach is implemented in the Optimizing Compiler Open64. The experimental results show that the proposed method can translate application with structure access into vectorizable codes, thereby advancing the execution efficiency adequately.

关键词： Decision support systems Arrays Layout Switches Indexes Transforms Benchmark testing

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