The flora of China is well known for its high diversity and endemism. Identifying centers of endemism and designating conservation priorities are essential goals for biodiversity studies.However, there is no comprehen...The flora of China is well known for its high diversity and endemism. Identifying centers of endemism and designating conservation priorities are essential goals for biodiversity studies.However, there is no comprehensive study from a rigorous phylogenetic perspective to understand patterns of diversity and endemism and to guide biodiversity conservation in China. We conducted a spatial phylogenetic analysis of the Chinese angiosperm flora at the generic level to identify centers of neo-and paleoendemism. Our results indicate that:(i) themajority of grid cells in China with significantly high phylogenetic endemism(PE) were located in the mountainous regions;(ii) four of the nine centers of endemism recognized, located in northern and western China, were recognized for the first time;(iii) arid and semiarid regions in Northwest China were commonly linked to significant PE, consistent with other spatial phylogenetic studies worldwide;and(iv) six highpriority conservation gaps were detected by overlaying the boundaries of China’s nature reserves on all significant PE cells. Overall, we conclude that the mountains of southern and northern China contain both paleo-endemics(ancient relictual lineages) and neo-endemics(recently diverged lineages). The areas we highlight as conservation priorities are important for broad-scale planning, especially in the context of evolutionary history preservation.展开更多
Observing nuclear neutrinoless double beta (0vββ) decay would be a revolutionary result in particle physics.Observing such a decay would prove that the neutrinos are their own antiparticles,help to study the absolut...Observing nuclear neutrinoless double beta (0vββ) decay would be a revolutionary result in particle physics.Observing such a decay would prove that the neutrinos are their own antiparticles,help to study the absolute mass of neutrinos,explore the origin of their mass,and may explain the matter-antimatter asymmetry in our universe by lepton number violation.We propose developing a time projection chamber (TPC) using high-pressure ^(82)SeF_(6) gas and Topmetal silicon sensors for readout in the China Jinping Underground Laboratory (CJPL) to search for neutrinoless double beta decay of82Se,called the NvDEx experiment.Besides being located at CJPL with the world’s thickest rock shielding,NvDEx combines the advantages of the high Qββ(2.996 MeV) of82Se and the TPC’s ability to distinguish signal and background events using their different topological characteristics.This makes NvDEx unique,with great potential for low-background and high-sensitivity 0 vββsearches.NvDEx-100,a NvDEx experiment phase with 100 kg of SeF_(6)gas,is being built,with plans to complete installation at CJPL by 2025.This report introduces 0 vββ physics,the NvDEx concept and its advantages,and the schematic design of NvDEx-100,its subsystems,and background and sensitivity estimation.展开更多
基金supported by grants from the Strategic Priority Research Program of the Chinese Academy of Sciences(XDB31000000 and XDA19050103)the International Partnership Program of the Chinese Academy of Sciences(151853KYSB20190027)+4 种基金the National Natural Science Foundation of China(NNSF31800178,31870506,and 32122009)the Sino-Africa Joint Research Center,the Chinese Academy of Sciences CAS International Research and Education Development Program(SAJC202101)the Jiangsu Natural Science Foundation(BK20181398)the Hundred Talents Program of CAS(Y8C3041100)supported in part by the Young Elite Scientists Sponsorship Program by China Association for Science and Technology(2018QNRC001)。
文摘The flora of China is well known for its high diversity and endemism. Identifying centers of endemism and designating conservation priorities are essential goals for biodiversity studies.However, there is no comprehensive study from a rigorous phylogenetic perspective to understand patterns of diversity and endemism and to guide biodiversity conservation in China. We conducted a spatial phylogenetic analysis of the Chinese angiosperm flora at the generic level to identify centers of neo-and paleoendemism. Our results indicate that:(i) themajority of grid cells in China with significantly high phylogenetic endemism(PE) were located in the mountainous regions;(ii) four of the nine centers of endemism recognized, located in northern and western China, were recognized for the first time;(iii) arid and semiarid regions in Northwest China were commonly linked to significant PE, consistent with other spatial phylogenetic studies worldwide;and(iv) six highpriority conservation gaps were detected by overlaying the boundaries of China’s nature reserves on all significant PE cells. Overall, we conclude that the mountains of southern and northern China contain both paleo-endemics(ancient relictual lineages) and neo-endemics(recently diverged lineages). The areas we highlight as conservation priorities are important for broad-scale planning, especially in the context of evolutionary history preservation.
基金This work was supported by the National Key Research and Development Program of China(Nos.2021YFA1601300 and 2022YFA1604703)From-0-to-1 Original Innovation Program of Chinese Academy of Sciences(No.ZDBS-LY-SLH014)+1 种基金International Partner Program of Chinese Academy of Sciences(No.GJHZ2067)National Natural Science Foundation of China Youth Science Fund Project(No.12105110).
文摘Observing nuclear neutrinoless double beta (0vββ) decay would be a revolutionary result in particle physics.Observing such a decay would prove that the neutrinos are their own antiparticles,help to study the absolute mass of neutrinos,explore the origin of their mass,and may explain the matter-antimatter asymmetry in our universe by lepton number violation.We propose developing a time projection chamber (TPC) using high-pressure ^(82)SeF_(6) gas and Topmetal silicon sensors for readout in the China Jinping Underground Laboratory (CJPL) to search for neutrinoless double beta decay of82Se,called the NvDEx experiment.Besides being located at CJPL with the world’s thickest rock shielding,NvDEx combines the advantages of the high Qββ(2.996 MeV) of82Se and the TPC’s ability to distinguish signal and background events using their different topological characteristics.This makes NvDEx unique,with great potential for low-background and high-sensitivity 0 vββsearches.NvDEx-100,a NvDEx experiment phase with 100 kg of SeF_(6)gas,is being built,with plans to complete installation at CJPL by 2025.This report introduces 0 vββ physics,the NvDEx concept and its advantages,and the schematic design of NvDEx-100,its subsystems,and background and sensitivity estimation.
