| 1 | Modes of genetic adaptations underlying functional innovations in the rumen显示文摘The rumen is the hallmark organ of ruminants and hosts a diverse ecosystem of microorganisms that facilitates efficient digestion of plant fibers.We analyzed 897 transcriptomes from three Cetartiodactyla lineages:ruminants,camels and cetaceans,as well as data from ruminant comparative genomics and functional assays to explore the genetic basis of rumen functional innovations.We identified genes with relatively high expression in the rumen,of which many appeared to be recruited from other tissues.These genes show functional enrichment in ketone body metabolism,regulation of microbial community,and epithelium absorption,which are the most prominent biological processes involved in rumen innovations.Several modes of genetic change underlying rumen functional innovations were uncovered,including coding mutations,genes newly evolved,and changes of regulatory elements.We validated that the key ketogenesis rate-limiting gene(HMGCS2)with five ruminant-specific mutations was under positive selection and exhibits higher synthesis activity than those of other mammals.Two newly evolved genes(LYZ1 and DEFB1)are resistant to Gram-positive bacteria and thereby may regulate microbial community equilibrium.Furthermore,we confirmed that the changes of regulatory elements accounted for the majority of rumen gene recruitment.These results greatly improve our understanding of rumen evolution and organ evo-devo in general. | Xiangyu Pan Yudong Cai Zongjun Li Xianqing Chen Rasmus Heller Nini Wang Yu Wang Chen Zhao Yong Wang Han Xu Songhai Li Ming Li Cunyuan Li Shengwei Hu Hui Li Kun Wang Lei Chen Bin Wei Zhuqing Zheng Weiwei Fu Yue Yang Tingting Zhang Zhuoting Hou Yueyang Yan Xiaoyang Lv Wei Sun Xinyu Li Shisheng Huang Lixiang Liu Shengyong Mao Wenqing Liu Jinlian Hua Zhipeng Li Guojie Zhang Yulin Chen Xihong Wang Qiang Qiu Brian PDalrymple Wen Wang Yu Jiang | 2021 | Science China(Life Sciences)2021，64，1： | 3 |
| 5 | High-order Asymptotic Analysis for the V-notch in a Power-law Hardening Material显示文摘The aim of this study is to determine the complete elastic–plastic stress asymptotic solutions at the plane V-notch tip with the two edges being clamped–clamped,free-clamped and free-friction.Firstly,the displacement and stress fields around the notch tip are expressed as asymptotic expansions,and then,these asymptotic expansions are substituted into the displacement–strain relation and the equilibrium equations to establish the ordinary differential equations(ODEs).Finally,the interpolating matrix method is employed to solve the eigenvalue problem of the ODEs,and consequently,the leading-order and higher-order stress and displacement eigen-solutions at the notch tip are obtained.Numerical examples demonstrate that the presented method has the advantages of great versatility and high accuracy. | Cong Li Bin Hu Zhongrong Niu Zongjun Hu Changzheng Cheng | 2021 | Acta Mechanica Solida Sinica2021，34，4： | 0 |
| 6 | Cryogenian and Ediacaran integrative stratigraphy,biotas,and paleogeographical evolution of the Qinghai-Tibetan Plateau and its surrounding areas显示文摘The complex evolutionary history of the Qinghai-Tibetan Plateau and its surrounding areas,including the continental blocks(Indian,Lhasa,South Qiangtang,Tarim,Olongbuluk,Central Qilian,Alxa,North China,Yangtze,Central Iran and Oman)and the orogenic belts between them,has long been the frontier in Earth science research.The Cryogenian and Ediacaran strata are extensively distributed in these blocks.Specifically,relatively complete Cryogenian and Ediacaran successions have been discovered in Oman,Indian,Yangtze,and Tarim blocks,while only the Ediacaran successions have been reported in Iran,the South Qiangtang,Central Qilian,Alxa,and North China blocks.Based on previous studies together with the integration of new materials and advancement obtained through the Second Tibetan Plateau Scientific Expedition and Research,this review aims to synthesize a correlative stratigraphic framework of the representative Cryogenian and Ediacaran sequences from the Qinghai-Tibetan Plateau and its surrounding areas.Furthermore,the Cryogenian and Ediacaran biotas and major geological events in these areas are comprehensively discussed in aspects of current research status.The results indicate that,in general,Ediacaran fossils of each area exhibit distinct features in preservation and assemblage composition,but the typical late Ediacaran fossils Cloudina and Shaanxilithes have been reported from most of these areas.In addition to the two global Cryogenian glaciations,late Ediacaran glaciogenic deposits are extensively recorded in the areas within and around the northern QinghaiTibetan Plateau(including the North China,Alxa,Central Qilian,Olongbuluk,and Tarim blocks,and the North Qilian Accretionary Belt),as well as central and southern Iran.However,further research is required to determine the age,distribution,and origin of these late Ediacaran glaciogenic deposits.Meanwhile,the middle Ediacaran DOUNCE/Shuram Excursion is widely documented in the Qinghai-Tibetan Plateau and its surrounding areas.The available data show that,after the break-up of the Rodinia supercontinent,most of the continental blocks in the areas were located along the northern margin of East Gondwana and a few(such as North China)were located between the Gondwana and Laurentia.In general,the paleogeographic evolution of most of these blocks during the Cryogenian and Ediacaran remains disputatious,necessitating further research to resolve the controversies surrounding their paleogeographic reconstruction models during this critical time interval. | Lang SUN Malik Muhammad Saud Sajid KHAN Chuan YANG Zhixin SUN Bing PAN Shehryar AHMED Lanyun MIAO Weichen SUN Chunlin HU Xiaojuan SUN Cui LUO Bo CHEN Zongjun YIN Fangchen ZHAO Guoxiang LI Maoyan ZHU | 2024 | Science China Earth Sciences2024，67，4： | 0 |
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