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Spectroscopic confirmation of a mature galaxy cluster at a redshift of 2 期刊论文
NATURE, 2020, 577 (7788) : 39-+
作者:  Willis, J. P.;  Canning, R. E. A.;  Noordeh, E. S.;  Allen, S. W.;  King, A. L.;  Mantz, A.;  Morris, R. G.;  Stanford, S. A.;  Brammer, G.
收藏  |  浏览/下载:12/0  |  提交时间:2020/07/03

Galaxy clusters are the most massive virialized structures in the Universe and are formed through the gravitational accretion of matter over cosmic time(1). The discovery(2) of an evolved galaxy cluster at redshift z = 2, corresponding to a look-back time of 10.4 billion years, provides an opportunity to study its properties. The galaxy cluster XLSSC 122 was originally detected as a faint, extended X-ray source in the XMM Large Scale Structure survey and was revealed to be coincident with a compact over-density of galaxies(2) with photometric redshifts of 1.9 +/- 0.2. Subsequent observations3 at millimetre wavelengths detected a Sunyaev-Zel'  dovich decrement along the line of sight to XLSSC 122, thus confirming the existence of hot intracluster gas, while deep imaging spectroscopy from the European Space Agency'  s X-ray Multi-Mirror Mission (XMM-Newton) revealed(4) an extended, X-ray-bright gaseous atmosphere with a virial temperature of 60 million Kelvin, enriched with metals to the same extent as are local clusters. Here we report optical spectroscopic observations of XLSSC 122 and identify 37 member galaxies at a mean redshift of 1.98, corresponding to a look-back time of 10.4 billion years. We use photometry to determine a mean, dust-free stellar age of 2.98 billion years, indicating that star formation commenced in these galaxies at a mean redshift of 12, when the Universe was only 370 million years old. The full range of inferred formation redshifts, including the effects of dust, covers the interval from 7 to 13. These observations confirm that XLSSC 122 is a remarkably mature galaxy cluster with both evolved stellar populations in the member galaxies and a hot, metal-rich gas composing the intracluster medium.


  
Childhood vaccines and antibiotic use in low- and middle-income countries 期刊论文
NATURE, 2020, 581 (7806) : 94-+
作者:  Louca, Stilianos;  Pennell, Matthew W.
收藏  |  浏览/下载:9/0  |  提交时间:2020/07/03

Vaccines may reduce the burden of antimicrobial resistance, in part by preventing infections for which treatment often includes the use of antibiotics(1-4). However, the effects of vaccination on antibiotic consumption remain poorly understood-especially in low- and middle-income countries (LMICs), where the burden of antimicrobial resistance is greatest(5). Here we show that vaccines that have recently been implemented in the World Health Organization'  s Expanded Programme on Immunization reduce antibiotic consumption substantially among children under five years of age in LMICs. By analysing data from large-scale studies of households, we estimate that pneumococcal conjugate vaccines and live attenuated rotavirus vaccines confer 19.7% (95% confidence interval, 3.4-43.4%) and 11.4% (4.0-18.6%) protection against antibiotic-treated episodes of acute respiratory infection and diarrhoea, respectively, in age groups that experience the greatest disease burden attributable to the vaccine-targeted pathogens(6,7). Under current coverage levels, pneumococcal and rotavirus vaccines prevent 23.8 million and 13.6 million episodes of antibiotic-treated illness, respectively, among children under five years of age in LMICs each year. Direct protection resulting from the achievement of universal coverage targets for these vaccines could prevent an additional 40.0 million episodes of antibiotic-treated illness. This evidence supports the prioritization of vaccines within the global strategy to combat antimicrobial resistance(8).


Pneumococcal and rotavirus vaccines have reduced antibiotic consumption substantially among children under five years old in low- and middle-income countries  however, this effect could be doubled if all countries were to implement vaccination programmes and meet universal vaccine coverage targets.


  
Tobacco smoking and somatic mutations in human bronchial epithelium 期刊论文
NATURE, 2020, 578 (7794) : 266-+
作者:  Sharma, Nikhil;  Flaherty, Kali;  Lezgiyeva, Karina;  Wagner, Daniel E.;  Klein, Allon M.;  Ginty, David D.
收藏  |  浏览/下载:33/0  |  提交时间:2020/07/03

Whole-genome sequencing of normal bronchial epithelium from 16 individuals shows that tobacco smoking increases genomic heterogeneity, mutational burden and driver mutations, whereas stopping smoking promotes replenishment of the epithelium with near-normal cells.


Tobacco smoking causes lung cancer(1-3), a process that is driven by more than 60 carcinogens in cigarette smoke that directly damage and mutate DNA(4,5). The profound effects of tobacco on the genome of lung cancer cells are well-documented(6-10), but equivalent data for normal bronchial cells are lacking. Here we sequenced whole genomes of 632 colonies derived from single bronchial epithelial cells across 16 subjects. Tobacco smoking was the major influence on mutational burden, typically adding from 1,000 to 10,000 mutations per cell  massively increasing the variance both within and between subjects  and generating several distinct mutational signatures of substitutions and of insertions and deletions. A population of cells in individuals with a history of smoking had mutational burdens that were equivalent to those expected for people who had never smoked: these cells had less damage from tobacco-specific mutational processes, were fourfold more frequent in ex-smokers than current smokers and had considerably longer telomeres than their more-mutated counterparts. Driver mutations increased in frequency with age, affecting 4-14% of cells in middle-aged subjects who had never smoked. In current smokers, at least 25% of cells carried driver mutations and 0-6% of cells had two or even three drivers. Thus, tobacco smoking increases mutational burden, cell-to-cell heterogeneity and driver mutations, but quitting promotes replenishment of the bronchial epithelium from mitotically quiescent cells that have avoided tobacco mutagenesis.


  
Northward range expansion in spring-staging barnacle geese is a response to climate change and population growth, mediated by individual experience 期刊论文
GLOBAL CHANGE BIOLOGY, 2019, 25 (11) : 3680-3693
作者:  Tombre, Ingunn M.;  Oudman, Thomas;  Shimmings, Paul;  Griffin, Larry;  Prop, Jouke
收藏  |  浏览/下载:12/0  |  提交时间:2019/11/27
age effects  dynamic strategies  explorative behaviour  food quality  population increase  range shift  spring migration  
Influence of Surface Topography on the Critical Carbon Dioxide Level Required for the Formation of a Modern Snowball Earth 期刊论文
JOURNAL OF CLIMATE, 2018, 31 (20) : 8463-8479
作者:  Liu, Yonggang;  Peltier, W. Richard;  Yang, Jun;  Hu, Yongyun
收藏  |  浏览/下载:9/0  |  提交时间:2019/04/09
Orographic effects  Topographic effects  Ice age  Climate change  Paleoclimate  Model comparison  
A New Perspective for Assessing Water Transport and Associated Retention Effects in a Large Reservoir 期刊论文
GEOPHYSICAL RESEARCH LETTERS, 2018, 45 (18) : 9642-9650
作者:  Xu, Bochao;  Yang, Disong;  Yao, Peng;  Burnett, William C.;  Ran, Xiangbin;  Charette, Matthew;  Huang, Xinying;  Liu, Sumei;  Yu, Zhigang
收藏  |  浏览/下载:5/0  |  提交时间:2019/04/09
radium  reservoir  water age  retention effects  nutrients  
Annual global mean temperature explains reproductive success in a marine vertebrate from 1955 to 2010 期刊论文
GLOBAL CHANGE BIOLOGY, 2018, 24 (4) : 1599-1613
作者:  Mauck, Robert A.;  Dearborn, Donald C.;  Huntington, Charles E.
收藏  |  浏览/下载:5/0  |  提交时间:2019/04/09
age effects  air temperature  climate change  global mean temperature  longitudinal study  long-term dataset  seabirds  sea surface temperature  storm-petrels  
Disease spread in age structured populations with maternal age effects 期刊论文
ECOLOGY LETTERS, 2017, 20 (4)
作者:  Clark, Jessica;  Garbutt, Jennie S.;  McNally, Luke;  Little, Tom J.
收藏  |  浏览/下载:3/0  |  提交时间:2019/04/09
Age  Daphnia  demography  ecology  epidemiology  evolution  immunity  maternal effects  modelling  senescence  
Effect of a fish stock's demographic structure on offspring survival and sensitivity to climate 期刊论文
PROCEEDINGS OF THE NATIONAL ACADEMY OF SCIENCES OF THE UNITED STATES OF AMERICA, 2017, 114 (6) : 1347-1352
作者:  Stige, Leif Christian;  Yaragina, Natalia A.;  Langangen, Oystein;  Bogstad, Bjarte;  Stenseth, Nils Chr.;  Ottersen, Geir
收藏  |  浏览/下载:8/0  |  提交时间:2019/11/27
fisheries  age and size truncation  population dynamics  climate effects  Gadus morhua