6684期

最新文章

• Interplay of competition and facilitation in grazing succession by migrant Serengeti herbivores AI翻译
  作者：Anderson, T. Michael; Hepler, Staci A.; Holdo, Ricardo M.; Donaldson, Jason E.; Erhardt, Robert J.; Hopcraft, J. Grant C.; Hutchinson, Matthew C.; Huebner, Sarah E.; Morrison, Thomas A.; Muday, Jeffry; Munuo, Issack N.; Palmer, Meredith S.; Pansu, Johan; Pringle, Robert M.; Sketch, Robert; Packer, Craig
  作者单位：Wake Forest University; Wake Forest University; University System of Georgia; University of Georgia; University of Glasgow; University of California System; University of California Merced; University of Minnesota System; University of Minnesota Twin Cities; Princeton University; Centre National de la Recherche Scientifique (CNRS); CNRS - Institute of Ecology & Environment (INEE); Universite Claude Bernard Lyon 1
  摘要：Competition, facilitation, and predation offer alternative explanations for successional patterns of migratory herbivores. However, these interactions are difficult to measure, leaving uncertainty about the mechanisms underlying body-size-dependent grazing-and even whether succession occurs at all. We used data from an 8-year camera-trap survey, GPS-collared herbivores, and fecal DNA metabarcoding to analyze the timing, arrival order, and interactions among migratory grazers in Serengeti Natio...
• Hepatic glycogenesis antagonizes lipogenesis by blocking S1P via UDPG AI翻译
  作者：Chen, Jie; Zhou, Yabo; Liu, Zhuohang; Lu, Yan; Jiang, Yishen; Cao, Kexin; Zhou, Nannan; Wang, Dianheng; Zhang, Chaoqi; Zhou, Ning; Shi, Keqing; Zhang, Lu; Zhou, Li; Wang, Zhenfeng; Zhang, Huafeng; Tang, Ke; Ma, Jingwei; Lv, Jiadi; Huang, Bo
  作者单位：Chinese Academy of Medical Sciences - Peking Union Medical College; Peking Union Medical College; Chinese Academy of Medical Sciences - Peking Union Medical College; Peking Union Medical College; Chinese Academy of Medical Sciences - Peking Union Medical College; Peking Union Medical College; Cancer Institute & Hospital - CAMS; Wenzhou Medical University; Tianjin Center for Disease Control & Prevention; Huazhong University of Science & Technology; Huazhong University of Science & Technology; Huazhong University of Science & Technology
  摘要：The identification of mechanisms to store glucose carbon in the form of glycogen rather than fat in hepatocytes has important implications for the prevention of nonalcoholic fatty liver disease (NAFLD) and other chronic metabolic diseases. In this work, we show that glycogenesis uses its intermediate metabolite uridine diphosphate glucose (UDPG) to antagonize lipogenesis, thus steering both mouse and human hepatocytes toward storing glucose carbon as glycogen. The underlying mechanism involves...
• Electrically driven proton transfer promotes Brempty setnsted acid catalysis by orders of magnitude AI翻译
  作者：Westendorff, Karl S.; Hulsey, Max J.; Wesley, Thejas S.; Roman-Leshkov, Yuriy; Surendranath, Yogesh
  作者单位：Massachusetts Institute of Technology (MIT); Massachusetts Institute of Technology (MIT)
  摘要：Electric fields play a key role in enzymatic catalysis and can enhance reaction rates by 100,000-fold, but the same rate enhancements have yet to be achieved in thermochemical heterogeneous catalysis. In this work, we probe the influence of catalyst potential and interfacial electric fields on heterogeneous Bronsted acid catalysis. We observed that variations in applied potential of similar to 380 mV led to a 100,000-fold rate enhancement for 1-methylcyclopentanol dehydration, which was cataly...
• Roaming in highly excited states: The central atom elimination of triatomic molecule decomposition AI翻译
  作者：Li, Zhenxing; Fu, Yan-lin; Luo, Zijie; Yang, Shuaikang; Wu, Yucheng; Wu, Hao; Wu, Guorong; Zhang, Weiqing; Fu, Bina; Yuan, Kaijun; Zhang, Donghui; Yang, Xueming
  作者单位：Chinese Academy of Sciences; Dalian Institute of Chemical Physics, CAS; Dalian Maritime University; Chinese Academy of Sciences; University of Chinese Academy of Sciences, CAS; Southern University of Science & Technology; Hefei National Laboratory
  摘要：Chemical reactions are generally assumed to proceed from reactants to products along the minimum energy path (MEP). However, straying from the MEP-roaming-has been recognized as an unconventional reaction mechanism and found to occur in both the ground and first excited states. Its existence in highly excited states is however not yet established. We report a dissociation channel to produce electronically excited fragments, S(D-1)+O-2(a(1)Delta(g)), from SO2 photodissociation in highly excited...
• A plant mechanism of hijacking pathogen virulence factors to trigger innate immunity AI翻译
  作者：Xiao, Yu; Sun, Guangzheng; Yu, Qiangsheng; Gao, Teng; Zhu, Qinsheng; Wang, Rui; Huang, Shijia; Han, Zhifu; Cervone, Felice; Yin, Heng; Qi, Tiancong; Wang, Yuanchao; Chai, Jijie
  作者单位：Tsinghua University; Tsinghua University; Nanjing Agricultural University; Nanjing Agricultural University; Nanjing Agricultural University; Westlake University; Westlake Laboratory; Sapienza University Rome; Chinese Academy of Sciences; Dalian Institute of Chemical Physics, CAS
  摘要：Polygalacturonase-inhibiting proteins (PGIPs) interact with pathogen-derived polygalacturonases to inhibit their virulence-associated plant cell wall-degrading activity but stimulate immunity-inducing oligogalacturonide production. Here we show that interaction between Phaseolus vulgaris PGIP2 (PvPGIP2) and Fusarium phyllophilum polygalacturonase (FpPG) enhances substrate binding, resulting in inhibition of the enzyme activity of FpPG. This interaction promotes FpPG-catalyzed production of lon...
• New Zealand scraps reforms AI翻译
  作者：Brainard, Jeffrey
• Protons are the new first responders Human STING's newfound function as a channel expands our understanding of immunity AI翻译
  作者：Liu, Bingxu
  作者单位：University of Washington; University of Washington Seattle
  摘要：Detection and clearance of invading pathogens are crucial for maintaining homeostasis in living systems, from bacteria to humans. First proposed by Charles Janeway in 1989, multiple sensors for sensing pathogen-associated molecular patterns (PAMPs) have now been discovered experimentally. Owing to the diversity of pathogens, human immune systems exhibit remarkable creativity in their detection of various PAMPs. The immune system can sense a wide spectrum of danger signals, which encompass macr...
• Jury rules noted climate scientist was defamed AI翻译
  作者：Voosen, Paul
• What's at stake for science in 'abortion pill' case AI翻译
  作者：Wadman, Meredith
• Water-induced strong isotropic MXene-bridged graphene sheets for electrochemical energy storage AI翻译
  作者：Yang, Jiao; Li, Mingzhu; Fang, Shaoli; Wang, Yanlei; He, Hongyan; Wang, Chenlu; Zhang, Zejun; Yuan, Bicheng; Jiang, Lei; Baughman, Ray H.; Cheng, Qunfeng
  作者单位：Beihang University; Chinese Academy of Sciences; Technical Institute of Physics & Chemistry, CAS; University of Texas System; University of Texas Dallas; Chinese Academy of Sciences; Institute of Process Engineering, CAS; Chinese Academy of Sciences; University of Science & Technology of China, CAS; Chinese Academy of Sciences; University of Science & Technology of China, CAS; University of Shanghai for Science & Technology
  摘要：Graphene and two-dimensional transition metal carbides and/or nitrides (MXenes) are important materials for making flexible energy storage devices because of their electrical and mechanical properties. It remains a challenge to assemble nanoplatelets of these materials at room temperature into in-plane isotropic, free-standing sheets. Using nanoconfined water-induced basal-plane alignment and covalent and pi-pi interplatelet bridging, we fabricated Ti3C2Tx MXene-bridged graphene sheets at room...