8029期

最新文章

• Extreme solar storms and the quest for exact dating with radiocarbon AI翻译
  作者：Heaton, T. J.; Bard, E.; Bayliss, A.; Blaauw, M.; Bronk Ramsey, C.; Reimer, P. J.; Turney, C. S. M.; Usoskin, I.
  作者单位：University of Leeds; Institut de Recherche pour le Developpement (IRD); Universite PSL; College de France; INRAE; Aix-Marseille Universite; Centre National de la Recherche Scientifique (CNRS); Queens University Belfast; University of Oxford; University of Technology Sydney; University of New South Wales Sydney; University of Oulu; University of Oulu
  摘要：Radiocarbon (14C) is essential for creating chronologies to study the timings and drivers of pivotal events in human history and the Earth system over the past 55,000 years. It is also a fundamental proxy for investigating solar processes, including the potential of the Sun for extreme activity. Until now, fluctuations in past atmospheric 14C levels have limited the dating precision possible using radiocarbon. However, the discovery of solar super-storms known as extreme solar particle events ...
• Cheap catalysts close the loop on plastics production AI翻译
  作者：[Anonymous]
  摘要：Process breaks down two of the most common plastics into raw ingredients.
• One month convection timescale on the surface of a giant evolved star AI翻译
  作者：Vlemmings, Wouter; Khouri, Theo; Arbab, Behzad Bojnordi; De Beck, Elvire; Maercker, Matthias
  作者单位：Chalmers University of Technology
  摘要：The transport of energy through convection is important during many stages of stellar evolution1,2, and is best studied in our Sun3 or giant evolved stars4. Features that are attributed to convection are found on the surface of massive red supergiant stars5-8. Also for lower-mass evolved stars, indications of convection are found9-13, but convective timescales and sizes remain poorly constrained. Models indicate that convective motions are crucial to produce strong winds that return the produc...
• Neoarchaean oxygen-based nitrogen cycle en route to the Great Oxidation Event AI翻译
  作者：Pellerin, Alice; Thomazo, Christophe; Ader, Magali; Rossignol, Camille; Rego, Eric Siciliano; Busigny, Vincent; Philippot, Pascal
  作者单位：Centre National de la Recherche Scientifique (CNRS); CNRS - Institute of Ecology & Environment (INEE); Universite Bourgogne Europe; Institut Universitaire de France; Universite Paris Cite; Centre National de la Recherche Scientifique (CNRS); University of Cagliari; University of California System; University of California San Diego; Scripps Institution of Oceanography; Universite de Montpellier; Centre National de la Recherche Scientifique (CNRS); Universidade de Sao Paulo
  摘要：The nitrogen isotopic composition of sedimentary rocks (delta N-15) can trace redox-dependent biological pathways and early Earth oxygenation(1,2). However, there is no substantial change in the sedimentary delta N-15 record across the Great Oxidation Event about 2.45 billion years ago (Ga)(3), a prominent redox change. This argues for a temporal decoupling between the emergence of the first oxygen-based oxidative pathways of the nitrogen cycle and the accumulation of atmospheric oxygen after ...
• Data on SDGs are riddled with gaps. Citizens can help AI翻译
  作者：Min, Yongyi; Chen, Haoyi; Perucci, Francesca
  摘要：The UN wants to put communities at the heart of its data-collection efforts in support of the Sustainable Development Goals. Now governments must step up.
• The race to save fossils exposed by Brazil's record-setting floods AI翻译
  作者：Rodrigues, Meghie
  摘要：As intermittent rain continues, palaeontologists in southern Brazil are working to extract dinosaur and other bones before they are damaged. As intermittent rain continues, palaeontologists in southern Brazil are working to extract dinosaur and other bones before they are damaged.
• Ancient Rapanui genomes reveal resilience and pre-European contact with the Americas AI翻译
  作者：Moreno-Mayar, J. Victor; da Mota, Barbara Sousa; Higham, Tom; Klemm, Signe; Edmunds, Moana Gorman; Stenderup, Jesper; Iraeta-Orbegozo, Miren; Laborde, Veronique; Heyer, Evelyne; Hochstetter, Francisco Torres; Friess, Martin; Allentoft, Morten E.; Schroeder, Hannes; Delaneau, Olivier; Malaspinas, Anna-Sapfo
  作者单位：University of Copenhagen; University of Copenhagen; University of Lausanne; Swiss Institute of Bioinformatics; University of Vienna; University of Vienna; University College Dublin; Museum National d'Histoire Naturelle (MNHN); Centre National de la Recherche Scientifique (CNRS); Universite Paris Cite; Museum National d'Histoire Naturelle (MNHN); Curtin University; Regeneron
  摘要：Rapa Nui (also known as Easter Island) is one of the most isolated inhabited places in the world. It has captured the imagination of many owing to its archaeological record, which includes iconic megalithic statues called moai1. Two prominent contentions have arisen from the extensive study of Rapa Nui. First, the history of the Rapanui has been presented as a warning tale of resource overexploitation that would have culminated in a major population collapse-the 'ecocide' theory2-4. Second, th...
• Europe sidelines Alzheimer's drug: lessons must be learnt AI翻译
  作者：Zetterberg, Henrik
  作者单位：University of Gothenburg
  摘要：If the European Medicines Agency takes an overly cautious approach to selecting specialists to advise on new medicines, people could be left without treatments.
• A researcher's quest to stop his work being plagiarized AI翻译
  作者：Garisto, Dan
  摘要：A scientist reviewing a study spotted figures that looked identical to his own, leading to a frustrating campaign to prevent its publication.
• Materials science Conduction tuned in a perovskite semiconductor AI翻译
  作者：Jiang, Fangyuan; Ginger, David S.
  作者单位：University of Washington; University of Washington Seattle