Science

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• Neanderthals and moderns mingled early and often AI翻译
  作者：Gibbons, Ann
• Integrated translation and metabolism in a partially self-synthesizing biochemical network AI翻译
  作者：Giaveri, Simone; Bohra, Nitin; Diehl, Christoph; Yang, Hao Yuan; Ballinger, Martine; Paczia, Nicole; Glatter, Timo; Erb, Tobias J.
  作者单位：Max Planck Society; Max Planck Society; Max Planck Society
  摘要：One of the hallmarks of living organisms is their capacity for self-organization and regeneration, which requires a tight integration of metabolic and genetic networks. We sought to construct a linked metabolic and genetic network in vitro that shows such lifelike behavior outside of a cellular context and generates its own building blocks from nonliving matter. We integrated the metabolism of the crotonyl-CoA/ethyl-malonyl-CoA/hydroxybutyryl-CoA cycle with cell-free protein synthesis using re...
• Molecular mechanism of plasmid elimination by the DdmDE defense system AI翻译
  作者：Loeff, Luuk; Adams, David W.; Chanez, Christelle; Stutzmann, Sandrine; Righi, Laurie; Blokesch, Melanie; Jinek, Martin
  作者单位：University of Zurich; Swiss School of Public Health (SSPH+); Swiss Federal Institutes of Technology Domain; Ecole Polytechnique Federale de Lausanne
  摘要：Seventh-pandemic Vibrio cholerae strains contain two pathogenicity islands that encode the DNA defense modules DdmABC and DdmDE. In this study, we used cryogenic electron microscopy to determine the mechanistic basis for plasmid defense by DdmDE. The helicase-nuclease DdmD adopts an autoinhibited dimeric architecture. The prokaryotic Argonaute protein DdmE uses a DNA guide to target plasmid DNA. The structure of the DdmDE complex, validated by in vivo mutational studies, shows that DNA binding...
• Programmed alternating current optimization of Cu-catalyzed C-H bond transformations AI翻译
  作者：Zeng, Li; Yang, Qinghong; Wang, Jianxing; Wang, Xin; Wang, Pengjie; Wang, Shengchun; Lv, Shide; Muhammad, Shabbir; Liu, Yichang; Yi, Hong; Lei, Aiwen
  作者单位：Wuhan University; Jiangxi Normal University
  摘要：Direct current (DC) electrosynthesis, which has undergone optimization over the past century, plays a pivotal role in a variety of industrial processes. Alternating current (AC) electrosynthesis, characterized by polarity reversal and periodic fluctuations, may be advantageous for multiple chemical reactions, but apparatus, principles, and application scenarios remain underdeveloped. In this work, we introduce a protocol for programmed AC (pAC) electrosynthesis that systematically adjusts curr...
• Ancient crystals show plate tectonics began early AI翻译
  作者：Voosen, Paul
• Stratospheric air intrusions promote global-scale new particle formation AI翻译
  作者：Zhang, Jiaoshi; Gong, Xianda; Crosbie, Ewan; Diskin, Glenn; Froyd, Karl; Hall, Samuel; Kupc, Agnieszka; Moore, Richard; Peischl, Jeff; Rollins, Andrew; Schwarz, Joshua; Shook, Michael; Thompson, Chelsea; Ullmann, Kirk; Williamson, Christina; Wisthaler, Armin; Xu, Lu; Ziemba, Luke; Brock, Charles A.; Wang, Jian
  作者单位：Washington University (WUSTL); National Aeronautics & Space Administration (NASA); NASA Langley Research Center; Science Systems & Applications Inc; University of Colorado System; University of Colorado Boulder; National Oceanic Atmospheric Admin (NOAA) - USA; National Center Atmospheric Research (NCAR) - USA; University of Vienna; Finnish Meteorological Institute; University of Helsinki; University of Innsbruck; University of Oslo
  摘要：New particle formation in the free troposphere is a major source of cloud condensation nuclei globally. The prevailing view is that in the free troposphere, new particles are formed predominantly in convective cloud outflows. We present another mechanism using global observations. We find that during stratospheric air intrusion events, the mixing of descending ozone-rich stratospheric air with more moist free tropospheric background results in elevated hydroxyl radical (OH) concentrations. Suc...
• Sound evidence for biodiversity monitoring AI翻译
  作者：Rasmussen, Jeppe H.; Stowell, Dan; Briefer, Elodie F.
  作者单位：University of Copenhagen; University of Agder; University of Agder; Tilburg University; Naturalis Biodiversity Center
• Partitioning polar-slush strategy in relaxors leads to large energy-storage capability AI翻译
  作者：Shu, Liang; Shi, Xiaoming; Zhang, Xin; Yang, Ziqi; Li, Wei; Ma, Yunpeng; Liu, Yi-Xuan; Liu, Lisha; Cheng, Yue-Yu-Shan; Wei, Liyu; Li, Qian; Huang, Houbing; Zhang, Shujun; Li, Jing-Feng
  作者单位：Tsinghua University; Beijing Institute of Technology; University of Science & Technology Beijing; University of Manchester; Nanjing University of Science & Technology; University of Wollongong
  摘要：Relaxor ferroelectric (RFE) films are promising energy-storage candidates for miniaturizing high-power electronic systems, which is credited to their high energy density (U-e) and efficiency. However, advancing their U-e beyond 200 joules per cubic centimeter is challenging, limiting their potential for next-generation energy-storage devices. We implemented a partitioning polar-slush strategy in RFEs to push the boundary of U-e. Guided by phase-field simulations, we designed and fabricated hig...
• International scope of biomedical research ethics review AI翻译
  作者：Rothstein, Mark A.; Zimmerer, Kelly Carty; Andanda, Pamela; Arawi, Thalia; Arzuaga, Fabiana; Chen, Haidan; de Vries, Martine; Dove, Edward S.; Ghaly, Mohammed; Hatanaka, Ryoko; Hendriks, Aart C.; Hernandez, Mireya Castaneda; Ho, Calvin W. L.; Joly, Yann; Krekora-Zajac, Dorota; Lee, Won Bok; Mattsson, Titti; Molnar-Gabor, Fruzsina; Namalwa, Kakai; Nicolas, Pilar; Nielsen, Jane; Nnamuchi, Obiajulu; Otlowski, Margaret; Palmour, Nicole; Rial-Sebbag, Emmanuelle; Siegal, Gil; Wathuta, Jane M.; Zawati, Ma'n H.; Knoppers, Bartha Maria
  摘要：Many countries consider long-term implications for society In the context of biomedical research involving human subjects, the review of research proposals by ethics committees in virtually every country has traditionally focused on informed consent and other protections for individuals participating in research ( 1 ). However, the substantial societal implications of modern biomedical research and the globalization of scientific inquiry make it important to understand whether research ethics ...
• Antagonistic conflict between transposon-encoded introns and guide RNAs AI翻译
  作者：Zedaveinyte, Rimante; Meers, Chance; Le, Hoang C.; Mortman, Edan E.; Tang, Stephen; Lampe, George D.; Pesari, Sanjana R.; Gelsinger, Diego R.; Wiegand, Tanner; Sternberg, Samuel H.
  作者单位：Columbia University; Columbia University; University of California System; University of California San Diego
  摘要：TnpB nucleases represent the evolutionary precursors to CRISPR-Cas12 and are widespread in all domains of life. IS605-family TnpB homologs function as programmable RNA-guided homing endonucleases in bacteria, driving transposon maintenance through DNA double-strand break-stimulated homologous recombination. In this work, we uncovered molecular mechanisms of the transposition life cycle of IS607-family elements that, notably, also encode group I introns. We identified specific features for a ca...