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11 New Transiting Brown Dwarfs and Very Low Mass Stars from TESS

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arXiv 2025年

作者： Vowell, Noah Rodriguez, Joseph E. Latham, David W. Quinn, Samuel N. Schulte, Jack Eastman, Jason D. Bieryla, Allyson Barkaoui, Khalid Ciardi, David R. Collins, Karen A. Girardin, Eric Heldridge, Ellie Kotten, Brooke Mancini, Luigi Murgas, Felipe Narita, Norio Radford, D.J. Relles, Howard M. Shporer, Avi Soares-Furtado, Melinda Strakhov, Ivan A. Ziegler, Carl Briceño, César Calkins, Michael L. Clark, Catherine A. Collins, Kevin I. Esquerdo, Gilbert A. Fajardo-Acosta, Sergio B. Fukui, Akihiko Watkins, Cristilyn N. He, Ruixuan Horne, Keith Jenkins, Jon M. Mann, Andrew W. Naponiello, Luca Palle, Enric Schwarz, Richard P. Seager, S. Southworth, John Srdoc, Gregor Swift, Jonathan J. Winn, Joshua N. Center for Data Intensive and Time Domain Astronomy Department of Physics and Astronomy Michigan State University East LansingMI48824 United States Center for Astrophysics | Harvard & Smithsonian 60 Garden St CambridgeMA02138 United States Astrobiology Research Unit Université de Liège 19C Allée du 6 Août Liège4000 Belgium Department of Earth Atmospheric and Planetary Science Massachusetts Institute of Technology 77 Massachusetts Avenue CambridgeMA02139 United States Calle Vía Láctea s/n Tenerife La Laguna38200 Spain NASA Exoplanet Science Institute Caltech/IPAC PasadenaCA91125 United States Grand Pra Observatory Les Hauderes1984 Switzerland The Thacher School 5025 Thacher Rd. OjaiCA93023 United States Department of Astronomy University of Michigan Ann ArborMI48109 United States Department of Physics University of Rome Tor Vergata Via della Ricerca Scientifica 1 RomeI-00133 Italy Max Planck Institute for Astronomy Königstuhl 17 HeidelbergD-69117 Germany INAF Osservatorio Astrofisico di Torino Via Osservatorio 20 Pino TorineseI-10025 Italy Tenerife La LagunaE-38205 Spain Tenerife La LagunaE-38206 Spain Komaba Institute for Science The University of Tokyo 3-8-1 Komaba Tokyo Meguro153-8902 Japan Astrobiology Center 2-21-1 Osawa Tokyo Mitaka181 8588 Japan Brierfield Observatory BowralNSW Australia Center for Astrophysics | Harvard & Smithsonian 60 Garden Street CambridgeMA02138 United States Department of Physics Kavli Institute for Astrophysics and Space Research Massachusetts Institute of Technology CambridgeMA02139 United States Department of Astronomy University of Wisconsin-Madison 475 N. Charter St. MadisonWI53706 United States Sternberg Astronomical Institute Lomonosov Moscow State University Universitetsky Pr. 13 Moscow119234 Russia Department of Physics Engineering and Astronomy Stephen F. Austin State University 1936 North St NacogdochesTX75962 United States SOAR Telescope NSF NOIRLab Casilla

We present the discovery of 11 new transiting brown dwarfs and low-mass M-dwarfs from NASA’s TESS mission: TOI-2844, TOI-3122, TOI-3577, TOI-3755, TOI-4462, TOI-4635, TOI-4737, TOI-4759, TOI-5240, TOI-5467, and TOI-5882. They consist of 5 brown dwarf companions and 6 very low mass stellar companions ranging in mass from 25 MJ to 128 MJ. We used a combination of photometric time-series, spectroscopic, and high resolution imaging follow-up as a part of the TESS Follow-up Observing Program (TFOP) in order to characterize each system. With over 50 transiting brown dwarfs confirmed, we now have a large enough sample to directly test different formation and evolutionary scenarios. We provide a renewed perspective on the transiting brown dwarf desert and its role in differentiating between planetary and stellar formation mechanisms. Our analysis of the eccentricity distribution for the transiting brown dwarf sample does not support previous claims of a transition between planetary and stellar formation at ∼42 MJ. We also contribute a first look into the metallicity distribution of transiting companions in the range 7 − 150 MJ, showing that this too does not support a ∼42 MJ transition. Finally, we also detect a significant lithium absorption feature in one of the brown dwarf hosts (TOI-5882) but determine that the host star is likely old based on rotation, kinematic, and photometric measurements. We therefore claim that TOI-5882 may be a candidate for planetary engulfment. Copyright © 2025, The Authors. All rights reserved.

关键词： NASA

Numerical studies of solutions for kinetic equations with many-particle collisions

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Journal of Physics: Conference Series 2019年第1期1163卷 012008-012008页

作者： Matveev, S A Stefonishin, D A Smirnov, A P Sorokin, A A Tyrtyshnikov, E E Skoltech Center for Computational and Data-Intensive Science and Engineering Skolkovo Institute for Science and Technology Moscow 121205 Russia Skoltech Center for Computational and Data-Intensive Science and Engineering Skolkovo Institute for Science and Technology Moscow 121205 Russia Faculty of Computational Mathematics and Cybernetics Lomonosov Moscow State University Moscow 119992 Russia Faculty of Computational Mathematics and Cybernetics Lomonosov Moscow State University Moscow 119992 Russia Nuclear Safety Institute Russian Academy of Sciences Moscow 115191 Russia Marchuk Institute of Numerical Mathematics Russian Academy of Sciences Moscow 119333 Russia

In this work we present a method of low-rank tensor decompositions to accelerate evaluation of the right-hand side of systems of kinetic equations with many-particle collisional terms. These equations can be interpreted as a generalization of classical Smoluchowski aggregation equations allowing one to consider not only binary collisions of particles but also triple collisions. Straight-forward evaluation of the right-hand side for such system of N equations with k = 1, 2,…, N requires O(N 3) numerical operations and we find such complexity too high for practical investigations. However, under assumptions that kinetic coefficients can be represented with either canonical polyadic (CP) or tensor train decomposition (TT) with the rank R ≪ N we can propose algorithms evaluating the right-hand side with much lower complexities: O(NRlog N) and O(NR 2 log N) for CP and TT respectively. We compare numerical solutions with different triple-collision rates and obtain a significant influence of accounting triple collisional effects.

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A census of dwarf galaxy satellites around LMC-mass galaxy NGC 2403

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arXiv 2024年

作者： Carlin, Jeffrey L. Sand, David J. Mutlu-Pakdil, Burçin Crnojević, Denija Doliva-Dolinsky, Amandine Garling, Christopher T. Peter, Annika H.G. Brodie, Jean P. Forbes, Duncan A. Hargis, Jonathan R. Romanowsky, Aaron J. Spekkens, Kristine Strader, Jay Willman, Beth AURA/Rubin Observatory 950 North Cherry Avenue TucsonAZ85719 United States Department of Astronomy/Steward Observatory 933 North Cherry Avenue TucsonAZ85721-0065 United States Department of Physics and Astronomy Dartmouth College HanoverNH03755 United States Department of Physics & Astronomy University of Tampa 401 West Kennedy Boulevard TampaFL33606 United States Department of Physics & Astronomy Dartmouth College HanoverNH03755 United States Department of Astronomy University of Virginia 530 McCormick Road CharlottesvilleVA22904 United States CCAPP Department of Physics Department of Astronomy The Ohio State University ColumbusOH43210 United States Centre for Astrophysics and Supercomputing Swinburne University John Street HawthornVIC3122 Australia Department of Astronomy & Astrophysics University of California Santa Cruz 1156 High Street Santa CruzCA95064 United States Centre for Astrophysics and Supercomputing Swinburne University HawthornVIC3122 Australia Space Telescope Science Institute 3700 San Martin Drive BaltimoreMD21218 United States University of California Observatories 1156 High Street Santa CruzCA95064 United States Department of Physics & Astronomy San José State University One Washington Square San JoseCA95192 United States Department of Physics Engineering Physics and Astronomy Queen's University KingstonONK7L 3N6 Canada Center for Data Intensive and Time Domain Astronomy Department of Physics and Astronomy Michigan State University East LansingMI48824 United States LSST Discovery Alliance 933 North Cherry Avenue TucsonAZ85719 United States

We present the first comprehensive census of the satellite population around a Large Magellanic Cloud (LMC) stellar-mass galaxy, as part of the Magellanic Analog Dwarf Companions and Stellar Halos (MADCASH) survey. We have surveyed NGC 2403 (D = 3.0 Mpc) with the Subaru/Hyper Suprime-Cam imager out to a projected radius of 90 kpc (with partial coverage extending out to ∼ 110 kpc, or ∼ 80% of the virial radius of NGC 2403), resolving stars in the uppermost ∼2.5 mags of its red giant branch. By looking for stellar overdensities in the red giant branch spatial density map, we identify 149 satellite candidates, of which only the previously discovered MADCASH J074238+65201- dw is a bona fide dwarf, together with the more massive and disrupting satellite DDO 44. We carefully assess the completeness of our search via injection of artificial dwarf galaxies into the images, finding that we are reliably sensitive to candidates down to MV ∼ -7.5 mag (and somewhat sensitive to even fainter satellites). A comparison of the satellite luminosity function of NGC 2403 down to this magnitude limit to theoretical expectations shows overall good agreement. This is the first of a full sample of 11 Magellanic Cloud-mass host galaxies we will analyze, creating a statistical sample that will provide the first quantitative constraints on hierarchical models of galaxy formation around low-mass hosts. © 2024, CC BY.

关键词： Population statistics

A systematic theoretical study on FeOx-supported single-atom catalysts： M1/FeOx for CO oxidation

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Nano Research 2018年第3期11卷 1599-1611页

作者： Jinxia Liang Qi Yu Xiaofeng Yang Tao Zhang Jun Li Guizhou Provincial Key Laboratory of Computational Nano-Material Science Guizhou Synergetic Innovation Center of Scientific Big Data for Advanced Manufacturing Technology Guizhou Education University Guiyang 550018 China Shaanxi Key Laboratory of Catalysis Shaanxi University of Technology Hanzhong 723000 China Department of Chemistry and Key Laboratory of Organic Optoelectronics & Molecular Engineering of Ministry of Education Tsinghua University Beijing 100084 China State Key Laboratory of Catalysis Dalian Institute of Chemical Physics Chinese Academy of Sciences Dalian 116023 China

A single-atom catalyst （SAC） that was first proposed by us in 2011 has aroused significant recent interest. Among the various SACs, FeOx-based ones including Pt1/FeOx, Ir1/FeOx, Au1/FeOx, Ni1/FeOx, and Fe1/FeOx have been investigated either experimentally or theoretically for CO oxidation. However, a systematic study of FeO,-based SACs has not been conducted. For a comprehensive understanding of FeOx-supported single-metal-atom catalysts, extensive density functional theory calculations were carried out on the activities and catalytic mechanisms of SACs with the 3d, 4d, and 5d metals of group VIII to IB, i.e., M1/FeOx （M = Fe, Co, Ni, Cu; Ru, Rh, Pd, Ag; Os, Ir, Pt, Au） for CO oxidation. Remarkably, a new noble metal SAC, Pd1/FeOx, with high activity in CO oxidation was found and is predicted to be even better than the previously reported Pt1/FeOx and Ni1/FeOx. In comparison, other M1/FeOx SACs （M = Fe, Co, Cu; Ru, Rh, Ag; Os, Ir, Au） showed only low activities in CO oxidation. Moreover, the adsorption strength of CO on the single-atom active sites was found to be the key in determining the catalytic activity of these SACs for CO oxidation, because it governs the recoverability of oxygen vacancies on their surfaces in the formation of a second CO2 during CO oxidation. Our systematic studies of FeOx-supported SACs will help in understanding the fundamental mechanisms of the interactions between singly dispersed surface metal atoms and FeOx substrate and in designing highly active FeOx-supported SACs.

关键词： single-atom catalyst M1/FeOx density functional theory heterogeneous catalysis

Distributed Deep Learning Model for Intelligent Video Surveillance Systems with Edge Computing

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arXiv 2019年

作者： Chen, Jianguo Li, Kenli Deng, Qingying Li, Keqin Yu, Philip S. College of Computer Science and Electronic Engineering Hunan University National Supercomputing Center in Changsha Hunan Changsha410082 China School of Mathematics and Computational Science Xiangtan University Xiangtan411105 China Department of Computer Science State University of New York New PaltzNY12561 United States Department of Computer Science University of Illinois at Chicago ChicagoIL60607 United States Institute for Data Science Tsinghua University Beijing100084 China

In this paper, we propose a Distributed Intelligent Video Surveillance (DIVS) system using Deep Learning (DL) algorithms and deploy it in an edge computing environment. We establish a multi-layer edge computing architecture and a distributed DL training model for the DIVS system. The DIVS system can migrate computing workloads from the network center to network edges to reduce huge network communication overhead and provide low-latency and accurate video analysis solutions. We implement the proposed DIVS system and address the problems of parallel training, model synchronization, and workload balancing. Task-level parallel and model-level parallel training methods are proposed to further accelerate the video analysis process. In addition, we propose a model parameter updating method to achieve model synchronization of the global DL model in a distributed EC environment. Moreover, a dynamic data migration approach is proposed to address the imbalance of workload and computational power of edge nodes. Experimental results showed that the EC architecture can provide elastic and scalable computing power, and the proposed DIVS system can efficiently handle video surveillance and analysis tasks. Copyright © 2019, The Authors. All rights reserved.

关键词： Edge computing

Apercal - The Apertif calibration pipeline

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arXiv 2021年

作者： Adebahr, Björn Schulz, R. Dijkema, T.J. Moss, V.A. Offringa, A.R. Kutkin, A. van der Hulst, J.M. Frank, B.S. Vilchez, N.P.E. Verstappen, J. Adams, E.K. de Blok, W.J.G. Denes, H. Hess, K.M. Lucero, D. Morganti, R. Oosterloo, T. Pisano, D.-J. Ivashina, M.V. van Cappellen, W.A. Connor, L.D. Coolen, A.H.W.M. Damstra, S. Loose, G.M. Maan, Y. Maccagni, F.M. Mika, A. Mulder, H. Oostrum, L.C. Orrú, E. Smits, R. van der Schuur, D. van Leeuwen, J. Vohl, D. Wijnholds, S.J. Ziemke, J. Bochum Germany ASTRON Dwingeloo Netherlands CSIRO Astronomy and Space Science Sydney Australia University of Sydney Sydney Australia Cavendish Laboratory Cambridge United Kingdom Kapteyn Astronomical Institute University of Groningen Groningen Netherlands Department of Physics Virginia Tech BlacksburgVA United States Astro Space Center of Lebedev Physical Institute Profsoyuznaya Str. 84/32 Moscow117997 Russia 2 Fir Street Observatory 7925 South Africa Inter-University Institute for Data Intensive Astronomy Department of Astronomy University of Cape Town Private Bag X3 Rondebosch 7701 South Africa University of Cape Town University Private Bag Rondebosch Cape Town7701 South Africa Department of Physics and Astronomy West Virginia University White Hall Box 6315 MorgantownWV26506 United States Dept. of Electrical Engineering Chalmers University of Technology Gothenburg Sweden Anton Pannekoek Institute University of Amsterdam Postbus 94249 Amsterdam1090 GE Netherlands Rijksuniversiteit Groningen Center for Information Technology P.O. Box 11044 Groningen9700 CA Netherlands Netherlands eScience Center Science Park 140 Amsterdam1098 XG Netherlands INAF Osservatorio Astronomico di Cagliari Via della Scienza 5 CA Selargius09047 Italy

Apertif (APERture Tile In Focus) is one of the Square Kilometre Array (SKA) pathfinder facilities. The Apertif project is an upgrade to the 50-year-old Westerbork Synthesis Radio Telescope (WSRT) using phased-array feed technology. The new receivers create 40 individual beams on the sky, achieving an instantaneous sky coverage of 6.5 square degrees. The primary goal of the Apertif Imaging Survey is to perform a wide survey of 3500 square degrees (AWES) and a medium deep survey of 350 square degrees (AMES) of neutral atomic hydrogen (up to a redshift of 0.26), radio continuum emission and polarisation. Each survey pointing yields 4.6 TB of correlated data. The goal of Apercal is to process this data and fully automatically generate science ready data products for the astronomical community while keeping up with the survey observations. We make use of common astronomical software packages in combination with Python based routines and parallelisation. We use an object oriented module-based approach to ensure easy adaptation of the pipeline. A Jupyter notebook based framework allows user interaction and execution of individual modules as well as a full automatic processing of a complete survey observation. If nothing interrupts processing, we are able to reduce a single pointing survey observation on our five node cluster with 24 physical cores and 256 GB of memory each within 24h keeping up with the speed of the surveys. The quality of the generated images is sufficient for scientific usage for 44 % of the recorded data products with single images reaching dynamic ranges of several thousands. Future improvements will increase this percentage to over 80 %. Our design allowed development of the pipeline in parallel to the commissioning of the Apertif system. © 2021, CC BY.

关键词： Surveys

Measurement of the U236(n,f) cross section for neutron energies from 0.4 MeV to 40 MeV from the back-streaming white neutron beam at the China Spallation Neutron Source

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Physical Review C 2020年第3期102卷 034604-034604页

作者： Zhizhou Ren Yiwei Yang Jie Wen Hairui Guo Zhongwei Wen Rong Liu Zijie Han Weili Sun Xingyan Liu Qiping Chen Tao Ye Qi An Huaiyong Bai Jie Bao Ping Cao Yonghao Chen Pinjing Cheng Zengqi Cui Ruirui Fan Changqing Feng Minhao Gu Fengqin Guo Changcai Han Guozhu He Yongcheng He Yuefeng He Hanxiong Huang Weiling Huang Xiru Huang Xiaolu Ji Xuyang Ji Haoyu Jiang Wei Jiang Hantao Jing Ling Kang Mingtao Kang Bo Li Lun Li Qiang Li Xiao Li Yang Li(a) Yang Li(b) Shubin Liu Guangyuan Luan Yinglin Ma Changjun Ning Binbin Qi Jie Ren Xichao Ruan Zhaohui Song Hong Sun Xiaoyang Sun Zhijia Sun Zhixin Tan Hongqing Tang Jingyu Tang Pengcheng Wang Qi Wang Taofeng Wang Yanfeng Wang Zhaohui Wang Zheng Wang Qingbiao Wu Xiaoguang Wu Xuan Wu Likun Xie Han Yi Li Yu Tao Yu Yongji Yu Guohui Zhang Jing Zhang Linhao Zhang Liying Zhang Qingmin Zhang Qiwei Zhang Xianpeng Zhang Yuliang Zhang Zhiyong Zhang Yingtan Zhao Liang Zhou Zuying Zhou Danyang Zhu Kejun Zhu Peng Zhu Institute of Nuclear Physics and Chemistry China Academy of Engineering Physics Mianyang 621900 China Institute of Applied Physics and Computational Mathematics Beijing 100088 China State Key Laboratory of Particle Detection and Electronics China Department of Modern Physics University of Science and Technology of China Hefei 230026 China State Key Laboratory of Nuclear Physics and Technology School of Physics Peking University Beijing 100871 China Key Laboratory of Nuclear Data China Institute of Atomic Energy Beijing 102413 China Institute of High Energy Physics Chinese Academy of Sciences (CAS) Beijing 100049 China Spallation Neutron Source Science Center Dongguan 523803 China University of South China Hengyang 421001 China Northwest Institute of Nuclear Technology Xi'an 710024 China Department of Engineering and Applied Physics University of Science and Technology of China Hefei 230026 China School of Physics Beihang University Beijing 100083 China Xi'an Jiaotong University Xi'an 710049 China

A new measurement of the neutron-induced fission cross section of U236 relative to the standard U235(n,f) cross section from 0.4–40 MeV was carried out by the time-of-flight method and a multicell fast fission ionization chamber at the China Spallation Neutron Source-Back-n white neutron source. The measured resonance peaks and the distribution of fission event-energy spectrum from the U235(n,f) reaction are in good agreement with that of the ENDF/B-VIII.0 evaluation, which confirms the reliability of the experimental setup. The measured U236/235U fission cross section ratios in 0.4–40 MeV neutron energy region are compared to previous measurements. The U236 fission cross section with the relative experimental uncertainty of 11.2%–2.9% in 0.4–1 MeV and 2.9%–2.8% in 1–40 MeV is determined and compared to calculation, previous measurements, and main evaluations. The present theoretical result with calculation program UNF reproduces the experimental data and the LANSCE data better than ENDF/B-VIII.0 evaluation does in the secondary fission region. The result confirms current evaluations from 0.4–40 MeV in most energy points and provides the experimental data for evaluating the discrepancies in the relevant energy region.

关键词： Fission Neutron physics A ≥ 220 Spectrometers & spectroscopic techniques

Highly Stereoselective Diels–Alder Reactions Catalyzed by Diboronate Complexes**

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Angewandte Chemie 2023年第33期135卷

作者： Dr. Yuan-He Li Dr. Su-Lei Zhang Dr. Yong Lu Bo Xiao Dr. Tian-Yu Sun Qian-Qian Xu Prof. Dr. Jia-Hua Chen Prof. Dr. Zhen Yang Key Laboratory of Bioorganic Chemistry and Molecular Engineering of Ministry of Education and Beijing National Laboratory for Molecular Science (BNLMS) Peking-Tsinghua Center for Life Sciences Peking University Beijing 100871 China Contribution: Data curation (lead) Investigation (lead) Methodology (lead) Validation (lead) Writing - original draft (lead) Writing - review & editing (lead) Contribution: Methodology (supporting) Writing - review & editing (supporting) Contribution: Data curation (supporting) Writing - review & editing (supporting) Lab of Computational Chemistry and Drug Design State Key Laboratory of Chemical Oncogenomics Peking University Shenzhen Graduate School Shenzhen 518055 China Contribution: Supervision (supporting) Writing - review & editing (supporting) Shenzhen Bay Laboratory Shenzhen 518055 China State Key Laboratory of Chemical Oncogenomics Key Laboratory of Chemical Genomics Peking University Shenzhen Graduate School Shenzhen 518055 China Contribution: Conceptualization (lead) Funding acquisition (lead) Supervision (lead) Writing - review & editing (supporting)

A highly enantioselective catalytic system for exo -Diels–Alder reactions was developed based on the newly discovered bispyrrolidine diboronates (BPDB). Activated by various Lewis or Brønsted acids, BPDB can catalyze highly stereoselective asymmetric exo -Diels–Alder reactions of monocarbonyl-based dienophiles. When 1,2-dicarbonyl-based dienophiles are used, the catalyst can sterically distinguish between the two binding sites, which leads to highly regioselective asymmetric Diels–Alder reactions. BPDB can be prepared as crystalline solids on a large scale and are stable under ambient condition. Single-crystal X-ray analysis of the structure for acid-activated BPDB indicated that its activation involves cleavage of a labile B←N bond.

关键词： Asymmetric Catalysis Bispyrrolidine Diboronates Diels–Alder Reaction Exo-Selectivity Pericyclic Reaction

Real-time prediction of COVID-19 related mortality using electronic health records

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arXiv 2020年

作者： Schwab, Patrick Mehrjou, Arash Parbhoo, Sonali Celi, Leo Anthony Hetzel, Jürgen Hofer, Markus Schölkopf, Bernhard Bauer, Stefan F. Hoffmann-La Roche Ltd Basel Switzerland Max Planck Institute for Intelligent Systems Tübingen Germany ETH Zurich Switzerland John A. Paulson School of Engineering and Applied Sciences Harvard University Cambridge United States Department of Medicine Beth Israel Deaconess Medical Center Harvard Medical School Boston United States MIT Critical Data Laboratory for Computational Physiology Institute for Medical Engineering and Science Harvard-MIT Health Sciences & Technology Cambridge United States Department of Medical Oncology and Pneumology University Hospital of Tübingen Germany Department of Pneumology Kantonsspital Winterthur Switzerland CIFAR Azrieli Global Scholar

Coronavirus Disease 2019 (COVID-19) is an emerging respiratory disease caused by the severe acute respiratory syndrome coronavirus 2 (SARS-CoV-2) with rapid human-to-human transmission and a high case fatality rate particularly in older patients. Due to the exponential growth of infections, many healthcare systems across the world are under pressure to care for increasing amounts of at-risk patients. Given the high number of infected patients, identifying patients with the highest mortality risk early is critical to enable effective intervention and optimal prioritisation of care. Here, we present the COVID-19 Early Warning System (CovEWS), a clinical risk scoring system for assessing COVID-19 related mortality risk. CovEWS provides continuous real-time risk scores for individual patients with clinically meaningful predictive performance up to 192 hours (8 days) in advance, and is automatically derived from patients' electronic health records (EHRs) using machine learning. We trained and evaluated CovEWS using de-identified data from a cohort of 66 430 COVID-19 positive patients seen at over 69 healthcare institutions in the United States (US), Australia, Malaysia and India amounting to an aggregated total of over 2 863 years of patient observation time. On an external test cohort of 5 005 patients, CovEWS predicts COVID-19 related mortality from 78.8% (95% confidence interval [CI]: 76.0, 84.7%) to 69.4% (95% CI: 57.6, 75.2%) specificity at a sensitivity greater than 95% between respectively 1 and 192 hours prior to observed mortality events - significantly outperforming existing generic and COVID-19 specific clinical risk scores. CovEWS could enable clinicians to intervene at an earlier stage, and may therefore help in preventing or mitigating COVID-19 related mortality. Copyright © 2020, The Authors. All rights reserved.

关键词： Coronavirus