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Global investments in pandemic preparedness and COVID-19: development assistance and domestic spending on health between 1990 and 2026

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The Lancet Global Health 2023年第3期11卷 e385-e413页

作者： Micah, Angela E. Bhangdia, Kayleigh Cogswell, Ian E. Lasher, Dylan Lidral-Porter, Brendan Maddison, Emilie R. Nguyen, Trang Nhu Ngoc Patel, Nishali Pedroza, Paola Solorio, Juan Stutzman, Hayley Tsakalos, Golsum Wang, Yifeng Warriner, Wesley Zhao, Yingxi Zlavog, Bianca S. Abbafati, Cristiana Abbas, Jaffar Abbasi-Kangevari, Mohsen Abbasi-Kangevari, Zeinab Abdelmasseh, Michael Abdulah, Deldar Morad Abedi, Aidin Abegaz, Kedir Hussein Abhilash, E.S. Aboagye, Richard Gyan Abolhassani, Hassan Abrigo, Michael R.M. Abubaker Ali, Hiwa Abu-Gharbieh, Eman Adem, Mohammed Hussien Afzal, Muhammad Sohail Ahmadi, Ali Ahmed, Haroon Ahmed Rashid, Tarik Aji, Budi Akbarialiabad, Hossein Akelew, Yibeltal Al Hamad, Hanadi Alam, Khurshid Alanezi, Fahad Mashhour Alanzi, Turki M. Al-Hanawi, Mohammed Khaled Alhassan, Robert Kaba Aljunid, Syed Mohamed Almustanyir, Sami Al-Raddadi, Rajaa M. Alvis-Guzman, Nelson Alvis-Zakzuk, Nelson J. Amare, Azmeraw T. Ameyaw, Edward Kwabena Amini-Rarani, Mostafa Amu, Hubert Ancuceanu, Robert Andrei, Tudorel Anwar, Sumadi Lukman Appiah, Francis Aqeel, Muhammad Arabloo, Jalal Arab-Zozani, Morteza Aravkin, Aleksandr Y. Aremu, Olatunde Aruleba, Raphael Taiwo Athari, Seyyed Shamsadin Avila-Burgos, Leticia Ayanore, Martin Amogre Azari, Samad Baig, Atif Amin Bantie, Abere Tilahun Barrow, Amadou Baskaran, Pritish Basu, Sanjay Batiha, Abdul-Monim Mohammad Baune, Bernhard T. Berezvai, Zombor Bhardwaj, Nikha Bhardwaj, Pankaj Bhaskar, Sonu Boachie, Micheal Kofi Bodolica, Virginia Botelho, João Silva Botelho Braithwaite, Dejana Breitborde, Nicholas J.K. Busse, Reinhard Cahuana-Hurtado, Lucero Catalá-López, Ferrán Chansa, Collins Charan, Jaykaran Chattu, Vijay Kumar Chen, Simiao Chukwu, Isaac Sunday Dadras, Omid Dandona, Lalit Dandona, Rakhi Dargahi, Abdollah Debela, Sisay Abebe Denova-Gutiérrez, Edgar Desye, Belay Dharmaratne, Samath Dhamminda Diao, Nancy Doan, Linh Phuong Dodangeh, Milad dos Santos, Wendel Mombaque Doshmangir, Leila Dube, John Eini, Ebrahim El Sayed Zaki, Maysaa El Tantawi, Maha Enyew, Daniel Berhanie Institute for Health Metrics and Evaluation University of Washington Seattle WA United States Department of Applied Mathematics University of Washington Seattle WA United States Department of Health Metrics Sciences School of Medicine University of Washington Seattle WA United States Nuffield Department of Medicine University of Oxford Oxford United Kingdom Department of Juridical and Economic Studies La Sapienza University Rome Italy Antai College of Economics Shanghai Jiao Tong University Shanghai China Non-communicable Diseases Research Center Tehran University of Medical Sciences Tehran Iran Research Center for Immunodeficiencies Tehran University of Medical Sciences Tehran Iran Multiple Sclerosis Research Center Tehran University of Medical Sciences Tehran Iran Children’s Medical Center Tehran University of Medical Sciences Tehran Iran Department of Epidemiology and Biostatistics Tehran University of Medical Sciences Tehran Iran Tehran Heart Center Tehran University of Medical Sciences Tehran Iran Faculty of Medicine Tehran University of Medical Sciences Tehran Iran National Institute for Health Research Tehran University of Medical Sciences Tehran Iran Department of Pharmacology Tehran University of Medical Sciences Tehran Iran Department of Cardiology Tehran University of Medical Sciences Tehran Iran Sina Trauma and Surgery Research Center Tehran University of Medical Sciences Tehran Iran Digestive Diseases Research Institute Tehran University of Medical Sciences Tehran Iran Department of Neurology Tehran University of Medical Sciences Tehran Iran Social Determinants of Health Research Center Shahid Beheshti University of Medical Sciences Tehran Iran Department of Epidemiology Shahid Beheshti University of Medical Sciences Tehran Iran Department of Health Economics and Statistics Shahid Beheshti University of Medical Sciences Tehran Iran Department of Neurosurgery Shahid Beheshti University of Medical Sciences Tehran Iran Ophthalmic R

Background: The COVID-19 pandemic highlighted gaps in health surveillance systems, disease prevention, and treatment globally. Among the many factors that might have led to these gaps is the issue of the financing of national health systems, especially in low-income and middle-income countries (LMICs), as well as a robust global system for pandemic preparedness. We aimed to provide a comparative assessment of global health spending at the onset of the pandemic;characterise the amount of development assistance for pandemic preparedness and response disbursed in the first 2 years of the COVID-19 pandemic;and examine expectations for future health spending and put into context the expected need for investment in pandemic preparedness. Methods: In this analysis of global health spending between 1990 and 2021, and prediction from 2021 to 2026, we estimated four sources of health spending: development assistance for health (DAH), government spending, out-of-pocket spending, and prepaid private spending across 204 countries and territories. We used the Organisation for Economic Co-operation and Development (OECD)'s Creditor Reporting System (CRS) and the WHO Global Health Expenditure Database (GHED) to estimate spending. We estimated development assistance for general health, COVID-19 response, and pandemic preparedness and response using a keyword search. Health spending estimates were combined with estimates of resources needed for pandemic prevention and preparedness to analyse future health spending patterns, relative to need. Findings: In 2019, at the onset of the COVID-19 pandemic, US$9·2 trillion (95% uncertainty interval [UI] 9·1–9·3) was spent on health worldwide. We found great disparities in the amount of resources devoted to health, with high-income countries spending $7·3 trillion (95% UI 7·2–7·4) in 2019;293·7 times the $24·8 billion (95% UI 24·3–25·3) spent by low-income countries in 2019. That same year, $43·1 billion in development assistance was provided

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Random close packing in protein cores

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Physical Review E 2016年第3期93卷 032415-032415页

作者： Jennifer C. Gaines W. Wendell Smith Lynne Regan Corey S. O'Hern Program in Computational Biology and Bioinformatics Yale University New Haven Connecticut 06520 USA Integrated Graduate Program in Physical and Engineering Biology (IGPPEB) Yale University New Haven Connecticut 06520 USA Department of Physics Yale University New Haven Connecticut 06520 USA Department of Molecular Biophysics & Biochemistry Yale University New Haven Connecticut 06520 USA Department of Chemistry Yale University New Haven Connecticut 06520 USA Department of Mechanical Engineering & Materials Science Yale University New Haven Connecticut 06520 USA Department of Applied Physics Yale University New Haven Connecticut 06520 USA

Shortly after the determination of the first protein x-ray crystal structures, researchers analyzed their cores and reported packing fractions ϕ≈0.75, a value that is similar to close packing of equal-sized spheres. A limitation of these analyses was the use of extended atom models, rather than the more physically accurate explicit hydrogen model. The validity of the explicit hydrogen model was proved in our previous studies by its ability to predict the side chain dihedral angle distributions observed in proteins. In contrast, the extended atom model is not able to recapitulate the side chain dihedral angle distributions, and gives rise to large atomic clashes at side chain dihedral angle combinations that are highly probable in protein crystal structures. Here, we employ the explicit hydrogen model to calculate the packing fraction of the cores of over 200 high-resolution protein structures. We find that these protein cores have ϕ≈0.56, which is similar to results obtained from simulations of random packings of individual amino acids. This result provides a deeper understanding of the physical basis of protein structure that will enable predictions of the effects of amino acid mutations to protein cores and interfaces of known structure.

关键词： Protein structure Proteins

Quantum Generation Dynamics of Coherent Phonons: Analysis of Transient Fano Resonance

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Journal of physics: Conference Series 2017年第1期864卷

作者： Yohei Watanabe Ken-ichi Hino Muneaki Hase Nobuya Maeshima Doctoral Program in Materials Science Graduate School of Pure and Applied Sciences University of Tsukuba Tsukuba Ibaraki 305-8573 Japan Division of Materials Science Faculty of Pure and Applied Sciences University of Tsukuba Tsukuba 305-8573 Japan Center for Computational Sciences University of Tsukuba Tsukuba 305-8577 Japan Division of Applied Physics Faculty of Pure and Applied Sciences University of Tsukuba Tsukuba 305-8573 Japan

We study the transient Fano resonance of a semiconductor Si observed in the early time region of coherent phonon generation induced by an ultrafast pump laser. We particularly examine effects of the detuning on the transient Fano resonance, where the detuning is de ned by the difference between the central frequency of the pump laser and the band gap. It is clari ed that asymmetric pro les of transient induced photoemission spectra, implying the Fano resonance, strongly depend on the detuning. This is attributed to energetically adjacent bosonic states, whose energy levels are strongly in uenced by the detuning.

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Minor contribution of quasars to ionizing photon budget AT Z - 6: Update on quasar luminosity function at the faint-end with Subaru/Suprime-Cam

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arXiv 2017年

作者： Onoue, Masafusa Kashikawa, Nobunari Willott, Chris J. Hibon, Pascale Im, Myungshin Furusawa, Hisanori Harikane, Yuichi Imanishi, Masatoshi Ishikawa, Shogo Kikuta, Satoshi Matsuoka, Yoshiki Nagao, Tohru Niino, Yuu Ono, Yoshiaki Ouchi, Masami Tanaka, Masayuki Tang, Ji-Jia Toshikawa, Jun Uchiyama, Hisakazu 2-21-1 Osawa Mitaka Tokyo181-8588 Japan National Astronomical Observatory of Japan 2-21-1 Osawa Mitaka Tokyo181-8588 Japan Herzberg Institute of Astrophysics National Research Council 5071 West Saanich Road VictoriaBCV9E 2E7 Canada European Southern Observatory Alonso de Cordova 3107 Casilla Santiago19001 Chile Astronomy Program Department of Physics and Astronomy Seoul National University 1-Gwanak-rho Gwanak-gu Seoul141-742 Korea Republic of Institute for Cosmic Ray Research University of Tokyo 5-1-5 Kashiwanoha Kashiwa Chiba277-8582 Japan Department of Physics Graduate School of Science University of Tokyo Bunkyo Tokyo113-0033 Japan Research Center for Space and Cosmic Evolution Ehime University Matsuyama Ehime790-8577 Japan Institute of Astronomy and Astrophysics Academia Sinica Taipei10617 Taiwan

We constrain the quasar contribution to cosmic reionization based on our deep optical survey of z - 6 quasars down to zR = 24.15 using Subaru/Suprime-Cam in three UKIDSS-DXS fields covering 6.5 deg2. In Kashikawa et al. (2015), we select 17 quasar candidates and report our initial discovery of two low-luminosity quasars (M1450 - −23) from seven targets, one of which might be a Lyα emitting galaxy. From an additional optical spectroscopy, none of the four candidates out of the remaining ten turn out to be genuine quasars. Moreover, the deeper optical photometry provided by the Hyper Suprime-Cam Subaru Strategic program (HSC-SSP) shows that, unlike the two already-known quasars, the i−z and z−y colors of the last six candidates are consistent with M- or L-type brown dwarfs. Therefore, the quasar luminosity function (QLF) in the previous paper is confirmed. Compiling QLF measurements from the literature over a wide magnitude range, including an extremely faint AGN candidate from Parsa et al. (2017), to fit them with a double power-law, we find that the best-fit faint-end slope is α = −2.04+0−0..3318 (−1.98+0−0..4821) and characteristic magnitude is M1450* = −25.8+1−1..19 (−25.7+1−1..08) in the case of two (one) quasar detection. Our result suggests that, if the QLF is integrated down to M1450 = −18, quasars produce - 1 − 12% of the ionizing photons required to ionize the whole universe at z - 6 with 2σ confidence level, assuming that the escape fraction is fesc = 1 and the IGM clumpy factor is C = 3. Even when the systematic uncertainties are taken into account, our result supports the scenario that quasars are the minor contributors of reionization. Copyright © 2017, The Authors. All rights reserved.

关键词： Galaxies

Education for the future

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science 2018年第6396期360卷 1409-1412页

作者： Cheung, Man Kit Schwendimann, Beat A. Ward, Adrian Pietrzak, Barbara Mollaoglu, Gurkan Duong, Michael Tran Allareddy, Veerasathpurush Ulltveit-Moe, Nils Dutton-Regester, Ken Zhang, Jian Scult, Matthew A. Singh, Poonam C. Yan, Hong Young Naz, Saima Isaacson, Kyle Dennis, Allison F. Beardsley, Felicia Rounds Al-Humaidan, Eyad Ibrahim Lo, Cody Jones, Tyler Sood, Prashant Nieuwenhuis, Rense Ali, Basant A. Yu, Kun-Hsing Arthur, Patrick Kobina Kumar, Brijesh Buschke, Falko Chen, Alexander Cingl, Lubomír O’Mullane, Anthony Peter Coetzee, Vinet Zaidi, Syed Shan-e-Ali Konstantinides, Nikos School of Life Sciences Chinese University of Hong Kong Shatin New Territories Hong Kong Graduate School of Education University of California Berkeley Berkeley 94720 CA United States University of Queensland St. Lucia 4072 QLD Australia Department of Hydrobiology Faculty of Biology Biological and Chemical Research Centre University of Warsaw Warsaw 02-089 Poland Department of Oncological Sciences University of Utah School of Medicine Salt Lake City 84112 UT United States Perelman School of Medicine University of Pennsylvania Philadelphia 19104 PA United States University of Illinois College of Dentistry Chicago 60612 IL United States Department of Information and Communication Technology University of Agder 4879 Grimstad Norway Department of Genetics and Computational Biology QIMR Berghofer Medical Research Institute Brisbane 4006 QLD Australia School of Safety and Environmental Engineering Hunan Institute of Technology Hengyang Hunan 421002 China Lahore 54000 Punjab Pakistan Department of Psychology and Neuroscience Duke University Durham 27708 NC United States National Museum of Marine Biology and Aquarium Chercheng Pingtung County 94450 Taiwan Division of Plant Microbe Interactions CSIR–National Botanical Research Institute Lucknow 226001 Uttar Pradesh India Program in Cell Molecular Developmental Biology and Biophysics (CMDB) Johns Hopkins University Baltimore 21218 MD United States Stem Cell and Tissue Re-Engineering Program King Faisal Specialist Hospital and Research Centre Riyadh Saudi Arabia Department of Sociology and Anthropology University of La Verne La Verne 91750 CA United States Department of Bioengineering University of Utah Salt Lake City 84112 UT United States MRC Centre for Medical Mycology University of Aberdeen Aberdeen AB25 2ZD United Kingdom Faculty of Medicine University of British Columbia Vancouver V6T 1Z2 BC Canada School of Engineering Brown University Providence 02912 RI United States

SDSS-IV MaNGA: Evidence of the importance of AGN feedback in low-mass galaxies

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arXiv 2017年

作者： Penny, Samantha J. Masters, Karen L. Smethurst, Rebecca Nichol, Robert C. Krawczyk, Coleman M. Bizyaev, Dmitry Greene, Olivia Liu, Charles Marinelli, Mariarosa Rembold, Sandro B. Riffel, Rogemar A. da Silva Ilha, Gabriele Wylezalek, Dominika Andrews, Brett H. Bundy, Kevin Drory, Niv Oravetz, Daniel Pan, Kaike Institute of Cosmology and Gravitation University of Portsmouth Burnaby Road PortsmouthPO1 3FX United Kingdom School of Physics and Astronomy University of Nottingham University Park NottinghamNG7 2RD United Kingdom Apache Point Observatory New Mexico State University P.O. Box 59 SunspotNM88349-0059 United States Sternberg Astronomical Institute Moscow State University Moscow Russia Department of Physics and Astronomy Vanderbilt University 201 West End Ave NashvilleTN37235 United States Physics Department Fisk University 1000 17th Ave N NashvilleTN37208 United States Astrophysical Observatory Department of Engineering Science and Physics College of Staten Island City University of New York 2800 Victory Boulevard Staten IslandNY10314 United States Department of Astrophysics and Hayden Planetarium American Museum of Natural History New YorkNY10024 United States Physics Program Graduate Center CUNY New YorkNY10016 United States School of Mathematics Science and Engineering Reynolds Community College RichmondVA23285 United States Departamento de Física CCNE Universidade Federal de Santa Maria Santa Maria RS97105-900 Korea Republic of Laboratório Interinstitucional de e-Astronomia 77 Rua General José Cristino Rio de Janeiro20921-400 Korea Republic of Center for Astrophysical Sciences Department of Physics and Astronomy Johns Hopkins University 3400 North Charles Street BaltimoreMD21218 United States European Southern Observatory Karl Schwarzschild StraSSe 2 Garching bei München85748 Germany PITT PACC Department of Physics and Astronomy University of Pittsburgh PittsburghPA15260 United States University of California Santa Cruz 1156 High St. Santa CruzCA95064 United States McDonald Observatory University of Texas at Austin 1 University Station AustinTX78712 United States

We present new evidence for AGN feedback in a subset of 69 quenched low-mass galaxies (M* . 5 × 109 M☉, Mr > −19) selected from the first two years of the SDSS-IV MaNGA survey. The majority (85 per cent) of these quenched galaxies appear to reside in a group environment. We find 6 galaxies in our sample that appear to have an active AGN that is preventing on-going star-formation;this is the first time such a feedback mechanism has been observed in this mass range. Interestingly, five of these six galaxies have an ionised gas component that is kinematically offset from their stellar component, suggesting the gas is either recently accreted or outflowing. We hypothesise these six galaxies are low-mass equivalents to the "red geysers" observed in more massive galaxies. Of the other 62 galaxies in the sample, we find 8 do appear for have some low-level, residual star formation, or emission from hot, evolved stars. The remaining galaxies in our sample have no detectable ionised gas emission throughout their structures, consistent with them being quenched. This work shows the potential for understanding the detailed physical properties of dwarf galaxies through spatially resolved spectroscopy. Copyright © 2017, The Authors. All rights reserved.

关键词： Galaxies

Causes of blindness and vision impairment in 2020 and trends over 30 years, and prevalence of avoidable blindness in relation to VISION 2020: the Right to Sight: an analysis for the Global Burden of Disease Study (vol 2, pg 144, 2021)

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LANCET GLOBAL HEALTH 2021年第4期9卷 E408-E408页

作者： Steinmetz, Jaimie D. Vision and Eye Research Institute Anglia Ruskin University Cambridge United Kingdom Biomedical Informatics Seoul National University Hospital Seoul South Korea Institute for Health Metrics and Evaluation University of Washington Seattle WA United States Department of Health Metrics Sciences School of Medicine University of Washington Seattle WA United States Institute of Health Services Research Yonsei University Seoul South Korea Department of Ophthalmology University of Washington Seattle WA United States Department of Mathematics Imperial College London London United Kingdom WHO Collaborating Centre for Public Health Education and Training Imperial College London London United Kingdom Department of Primary Care and Public Health Imperial College London London United Kingdom School of Population and Global Health University of Melbourne Carlton VIC Australia School of Optometry and Vision Science UNSW Sydney NSW Australia Brien Holden Vision Institute Sydney Australia Department of Ophthalmology University of Adelaide Adelaide SA Australia Department of Parasitology and Mycology Jahrom University of Medical Sciences Jahrom Iran Department of Clinical Sciences University of Sharjah Sharjah United Arab Emirates Ophthalmic Research Center Shahid Beheshti University of Medical Sciences Tehran Iran Department of Ophthalmology Shahid Beheshti University of Medical Sciences Tehran Iran Research Institute for Endocrine Sciences Shahid Beheshti University of Medical Sciences Tehran Iran Ophthalmic Epidemiology Research Center Shahid Beheshti University of Medical Sciences Tehran Iran Health Services Management Department Qazvin University of Medical Sciences Qazvin Iran Department of Systems Populations and Leadership University of Michigan Ann Arbor MI United States Department of Medicine Sofia Ismail Memorial Medical Centre Bogura Bangladesh The Fred Hollows Foundation Sydney NSW Australia Berhan Public Health & Eye Care Consultancy Addis A

Hospital El Salvador: a novel paradigm of intensive care in response to COVID-19 in central America. Lancet Glob Health 2021;9: e241?42?In this Comment, the conflict of interest statement should have included the following: ?By virtue of their roles within a public hospital or the Ministry of Health, MB, LC, WH, and XS are government employees. The findings and conclusions in the Comment are only those of the authors.? This correction has been made as of Feb 26, 2021.

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Gaia17biu/SN 2017egm IN NGC 3191: THE CLOSEST HYDROGEN-POOR SUPERLUMINOUS SUPERNOVA TO DATE IS IN A "NORMAL", MASSIVE, METAL-RICH SPIRAL GALAXY

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arXiv 2017年

作者： Bose, Subhash Dong, Subo Pastorello, A. Filippenko, Alexei V. Kochanek, C.S. Mauerhan, Jon Romero-Cañizales, C. Brink, Thomas G. Chen, Ping Prieto, J.L. Post, R. Ashall, Christopher Grupe, Dirk Tomasella, L. Benetti, Stefano Shappee, B.J. Stanek, K.Z. Cai, Zheng Falco, E. Lundqvist, Peter Mattila, Seppo Mutel, Robert Ochner, Paolo Pooley, David Stritzinger, M.D. Villanueva, S. Zheng, WeiKang Beswick, R.J. Brown, Peter J. Cappellaro, E. Davis, Scott Fraser, Morgan de Jaeger, Thomas Elias-Rosa, N. Gall, C. Gaudi, B. Scott Herczeg, Gregory J. Hestenes, Julia Holoien, T.W.-S. Hosseinzadeh, Griffin Hsiao, E.Y. Hu, Shaoming Jaejin, Shin Jeffers, Ben Koff, R.A. Kumar, Sahana Kurtenkov, Alexander Lau, Marie Wingyee Prentice, Simon Reynolds, T. Rudy, Richard J. Shahbandeh, Melissa Somero, Auni Stassun, Keivan G. Thompson, Todd A. Valenti, Stefano Woo, Jong-Hak Yunus, Sameen Kavli Institute for Astronomy and Astrophysics Peking University Yi He Yuan Road 5 Hai Dian District Beijing100871 China INAF-Osservatorio Astronomico di Padova Vicolo dell’Osservatorio 5 PadovaI-35122 Italy Department of Astronomy University of California BerkeleyCA94720-3411 United States Miller Institute for Basic Research in Science University of California BerkeleyCA94720 United States Department of Astronomy Ohio State University 140 W. 18th Avenue ColumbusOH43210 United States Ohio State University 191 W. Woodruff Avenue ColumbusOH43210 United States Millennium Institute of Astrophysics Santiago Chile Núcleo de Astronomía de la Facultad de Ingeniería y Ciencias Universidad Diego Portales Av. Ej ército 441 Santiago Chile Post Observatory LexingtonMA02421 Department of Physics Florida State University 77 Chieftain Way TallahasseeFL32306 United States Department of Earth and Space Science Morehead State University 235 Martindale Dr. MoreheadKY40351 United States Carnegie Observatories 813 Santa Barbara Street PasadenaCA91101 United States Hubble Fellow Carnegie-Princeton Fellow UCO/Lick Observatory University of California at Santa Cruz Santa CruzCA95064 United States Harvard-Smithsonian Center for Astrophysics 60 Garden Street CambridgeMA02138 United States Department of Astronomy and The Oskar Klein Centre AlbaNova University Center Stockholm University StockholmSE-10691 Sweden Tuorla Observatory Department of Physics and Astronomy University of Turku Vislntie 20 PiikkiFI-21500 Finland Department of Physics and Astronomy University of Iowa Trinity University Department of Physics & Astronomy One Trinity Place San AntonioTX78212 United States Department of Physics and Astronomy Aarhus University Ny Munkegade 120 Aarhus CDK-8000 Denmark Jodrell Bank Centre for Astrophysics & e-MERLIN School of Physics and Astronomy University of Manchester ManchesterM13 9PL United Kingdom George P. and Cynthia Woods Mitchell Insti

Hydrogen-poor superluminous supernovae (SLSNe-I) have been predominantly found in low-metallicity, star-forming dwarf galaxies. Here we identify Gaia17biu/SN 2017egm as an SLSN-I occurring in a "normal" spiral galaxy (NGC 3191) in terms of stellar mass (several times 1010 M) and metallicity (roughly Solar). At redshift z = 0.031, Gaia17biu is also the lowest redshift SLSN-I to date, and the absence of a larger population of SLSNe-I in dwarf galaxies of similar redshift suggests that metallicity is likely less important to the production of SLSNe-I than previously believed. With the smallest distance and highest apparent brightness for an SLSN-I, we are able to study Gaia17biu in unprecedented detail. Its pre-peak near-ultraviolet to optical color is similar to that of Gaia16apd and among the bluest observed for an SLSN-I while its peak luminosity (Mg = −21 mag) is substantially lower than Gaia16apd. Thanks to the high signal-to-noise ratios of our spectra, we identify several new spectroscopic features that may help to probe the properties of these enigmatic explosions. We detect polarization at the ∼ 0.5% level that is not strongly dependent on wavelength, suggesting a modest, global departure from spherical symmetry. In addition, we put the tightest upper limit yet on the radio luminosity of an SLSN-I with 26 erg s−1 Hz−1 at 10 GHz, which is almost a factor of 40 better than previous upper limits and one of the few measured at an early stage in the evolution of an SLSN-I. This limit largely rules out an association of this SLSNe-I with known populations of gamma-ray burst (GRB) like central engines. Copyright © 2017, The Authors. All rights reserved.

关键词： Luminance

Stellar & planetary parameters for K2’S late type dwarf systems from C1 TO C5

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arXiv 2017年

作者： Martinez, Arturo O. Crossfield, Ian J.M. Schlieder, Joshua E. Dressing, Courtney D. Obermeier, Christian Livingston, John Ciceri, Simona Peacock, Sarah Beichman, Charles A. Lépine, Sébastien Aller, Kimberly M. Chance, Quadry A. Petigura, Erik A. Howard, Andrew W. Werner, Michael W. Department of Astronomy San Diego State University 5500 Campanile Drive San DiegoCA United States Department of Physics and Astronomy Georgia State University GA United States Steward Observatory University of Arizona TucsonAZ United States Lunar & Planetary Laboratory University of Arizona TucsonAZ United States Astronomy and Astrophysics Department UC Santa Cruz Santa CruzCA United States NASA NASA Ames Research Center Moffett FieldCA United States NASA Exoplanet Science Institute California Institute of Technology PasadenaCA United States NASA Postdoctoral Program Division of Geological and Planetary Sciences California Institute of Technology PasadenaCA United States Max Planck Institut für Astronomie Heidelberg Germany Max-Planck-Institute for Extraterrestrial Physics Garching Germany Department of Astronomy Graduate School of Science University of Tokyo 7-3-1 Bunkyo-ku Tokyo113- 0033 Japan Department of Astronomy Stockholm University StockholmSE-106 91 Sweden Institute for Astronomy University of Hawai’i at Mānoa HonoluluHI United States Steward Observatory University of Arizona TucsonAZ United States Hubble Department of Astronomy California Institute of Technology PasadenaCA91125 United States Jet Propulsion Laboratory PasadenaCA United States

The NASA K2 mission uses photometry to find planets transiting stars of various types. M dwarfs are of high interest since they host more short-period planets than any other type of main-sequence stars and transiting planets around M dwarfs have deeper transits compared to other main-sequence stars. In this paper, we present stellar parameters from K and M dwarfs hosting transiting planet candidates discovered by our team. Using the SOFI spectrograph on the European Southern Observatory’s New Technology Telescope, we obtained R ≈ 1000 J-, H-, and K-band (0.95 - 2.52 µm) spectra of 34 late-type K2 planet and candidate planet host systems and 12 bright K4-M5 dwarfs with interferometrically measured radii and effective temperatures. Out of our 34 late-type K2 targets, we identify 27 of these stars as M dwarfs. We measure equivalent widths of spectral features, derive calibration relations using stars with interferometric measurements, and estimate stellar radii, effective temperatures, masses, and luminosities for the K2 planet hosts. Our calibrations provide radii and temperatures with median uncertainties of 0.059 Ro (16.09%) and 160 K (4.33%), respectively. We then reassess the radii and equilibrium temperatures of known and candidate planets based on our spectroscopically derived stellar parameters. Since a planet’s radius and equilibrium temperature depend on the parameters of its host star, our study provides more precise planetary parameters for planets and candidates orbiting late-type stars observed with K2. We find a median planet radius and an equilibrium temperature of approximately 3R⊕ and 500 K, respectively, with several systems (K2-18b and K2-72e) receiving near-Earth-like levels of incident irradiation. Copyright © 2017, The Authors. All rights reserved.

关键词： Planets