Background Planktonic bacteria and archaea play a key role in river nutrient biogeochemical cycling;however,their respective community assembly and how to maintain their diversity are not well known in dammed rivers.T...Background Planktonic bacteria and archaea play a key role in river nutrient biogeochemical cycling;however,their respective community assembly and how to maintain their diversity are not well known in dammed rivers.Therefore,a seasonal survey of planktonic bacterial and archaeal community compositions and related environmental factors was conducted in 16 cascade reservoirs and corresponding river waters on the Wujiang River and the Pearl River in southwest China to understand the above mechanisms.Results Deterministic processes dominated bacterial and archaeal community assembly.The structural equation models showed that water temperature can directly or indirectly affect the microbial diversity.Interestingly,planktonic bacterial diversity increased with increasing water temperature,while archaea showed the opposite trend;the overall diversity of bacteria and archaea was no significant changes with changeable water temperature.Abundant microbes had a stronger distance–decay relationship than middle and rare ones,and the relationship was stronger in winter and spring than in summer and autumn.Conclusions Planktonic bacteria and archaea in dammed rivers had different biogeographic distributions,and water temperature was a key controlling factor.The different responses of planktonic bacterial and archaeal diversity to water temperature could be due to their different phylogenetic diversity.This ultimately maintained the stability of total microbial community diversity.This study reveals the different responses of planktonic bacteria and archaea to water temperature and perfects the theoretical framework for planktonic microbial biogeography in dammed rivers.展开更多
Small RNAs（s RNAs） play essential roles in plants upon biotic stress. Plants utilize RNA silencing machinery to facilitate pathogen-associated molecular pattern-triggered immunity and effector-triggered immunity to ...Small RNAs（s RNAs） play essential roles in plants upon biotic stress. Plants utilize RNA silencing machinery to facilitate pathogen-associated molecular pattern-triggered immunity and effector-triggered immunity to defend against pathogen attack or to facilitate defense against insect herbivores. Pathogens, on the other hand, are also able to generate effectors and s RNAs to counter the host immune response. The arms race between plants and pathogens/insect herbivores has triggered the evolution of s RNAs,RNA silencing machinery and pathogen effectors. A great number of studies have been performed to investigate the roles of s RNAs in plant defense, bringing in the opportunity to utilize s RNAs in plant protection. Transgenic plants with pathogen-derived resistance ability or transgenerational defense have been generated, which show promising potential as solutions for pathogen/insect herbivore problems in the field. Here we summarize the recent progress on the function of s RNAs in response to biotic stress, mainly in plant-pathogen/insect herbivore interaction,and the application of s RNAs in disease and insect herbivore control.展开更多
Sn Se emerges as one of the most promising Te-free thermoelectric materials due to its strong anharmonicity and multiple valence bands structure.Recently,compositing has been proven effective in optimizing thermoelect...Sn Se emerges as one of the most promising Te-free thermoelectric materials due to its strong anharmonicity and multiple valence bands structure.Recently,compositing has been proven effective in optimizing thermoelectric performance of various metal chalcogenides.Herein,a series of Sn Se-x Cu_(2)S(x=0,0.5%,1%,3%,5%)materials have been fabricated via solution synthesis,particle blending,and spark plasma sintering in sequence.After incorporating Cu_(2)S,the materials become Sn Se based composites with Cu doping,S substitution and Cu_(2)Sn Se_(3)secondary phase.We elucidate that the power factor of polycrystalline Sn Se can be tuned and enhanced at varied temperature ranges through adjusting the addition amount of Cu_(2)S.Additionally,the composites achieve suppressed lattice thermal conductivity when compared to Sn Se itself,as the introduced point defects and Sn Se/Cu_(2)Sn Se_(3)interfaces intensify phonon scattering.Consequently,Sn Se-0.5%Cu_(2)S and Sn Se-3%Cu_(2)S achieve a peak z T of 0.70 at 830 K(intermediate temperature range)and a highly increased z T of 0.28 at 473 K(low temperature range),respectively,which are~130%and 200%of values reached by Sn Se at the corresponding temperatures.The study demonstrates that our approach,which combines compositing with elemental doping and substitution,is effective in optimizing the thermoelectric performance of Sn Se at varied temperature ranges.展开更多
基金supported by the National Natural Science Foundation of China(42293264)the Special Foundation for National Science and Technology Basic Research Program of China(2021FY101000).
文摘Background Planktonic bacteria and archaea play a key role in river nutrient biogeochemical cycling;however,their respective community assembly and how to maintain their diversity are not well known in dammed rivers.Therefore,a seasonal survey of planktonic bacterial and archaeal community compositions and related environmental factors was conducted in 16 cascade reservoirs and corresponding river waters on the Wujiang River and the Pearl River in southwest China to understand the above mechanisms.Results Deterministic processes dominated bacterial and archaeal community assembly.The structural equation models showed that water temperature can directly or indirectly affect the microbial diversity.Interestingly,planktonic bacterial diversity increased with increasing water temperature,while archaea showed the opposite trend;the overall diversity of bacteria and archaea was no significant changes with changeable water temperature.Abundant microbes had a stronger distance–decay relationship than middle and rare ones,and the relationship was stronger in winter and spring than in summer and autumn.Conclusions Planktonic bacteria and archaea in dammed rivers had different biogeographic distributions,and water temperature was a key controlling factor.The different responses of planktonic bacterial and archaeal diversity to water temperature could be due to their different phylogenetic diversity.This ultimately maintained the stability of total microbial community diversity.This study reveals the different responses of planktonic bacteria and archaea to water temperature and perfects the theoretical framework for planktonic microbial biogeography in dammed rivers.
基金supported by the Strategic Priority Research program of the CAS(No.XDB11050700)National Natural Science Foundation of China(No.31471782,No.91540116)+1 种基金National Basic Research Program of China(No.2014CB138405)Open research Fund Program of State Key Laboratory of Integrated Pest Management(Chinese IPM1503)for financial support
文摘Small RNAs（s RNAs） play essential roles in plants upon biotic stress. Plants utilize RNA silencing machinery to facilitate pathogen-associated molecular pattern-triggered immunity and effector-triggered immunity to defend against pathogen attack or to facilitate defense against insect herbivores. Pathogens, on the other hand, are also able to generate effectors and s RNAs to counter the host immune response. The arms race between plants and pathogens/insect herbivores has triggered the evolution of s RNAs,RNA silencing machinery and pathogen effectors. A great number of studies have been performed to investigate the roles of s RNAs in plant defense, bringing in the opportunity to utilize s RNAs in plant protection. Transgenic plants with pathogen-derived resistance ability or transgenerational defense have been generated, which show promising potential as solutions for pathogen/insect herbivore problems in the field. Here we summarize the recent progress on the function of s RNAs in response to biotic stress, mainly in plant-pathogen/insect herbivore interaction,and the application of s RNAs in disease and insect herbivore control.
基金the National Natural Science Foundation of China(Nos.51802034,11674040,51672270,11904039)the Chongqing Research Program of Basic Research and Frontier Technology(No.cstc2018jcyj AX0346)+1 种基金the Chongqing Entrepreneurship and Innovation Program for the Returned Overseas Chinese Scholars(No.cx2018020)the Fundamental Research Funds for the Central Universities(No.2019CDQYCL003)。
文摘Sn Se emerges as one of the most promising Te-free thermoelectric materials due to its strong anharmonicity and multiple valence bands structure.Recently,compositing has been proven effective in optimizing thermoelectric performance of various metal chalcogenides.Herein,a series of Sn Se-x Cu_(2)S(x=0,0.5%,1%,3%,5%)materials have been fabricated via solution synthesis,particle blending,and spark plasma sintering in sequence.After incorporating Cu_(2)S,the materials become Sn Se based composites with Cu doping,S substitution and Cu_(2)Sn Se_(3)secondary phase.We elucidate that the power factor of polycrystalline Sn Se can be tuned and enhanced at varied temperature ranges through adjusting the addition amount of Cu_(2)S.Additionally,the composites achieve suppressed lattice thermal conductivity when compared to Sn Se itself,as the introduced point defects and Sn Se/Cu_(2)Sn Se_(3)interfaces intensify phonon scattering.Consequently,Sn Se-0.5%Cu_(2)S and Sn Se-3%Cu_(2)S achieve a peak z T of 0.70 at 830 K(intermediate temperature range)and a highly increased z T of 0.28 at 473 K(low temperature range),respectively,which are~130%and 200%of values reached by Sn Se at the corresponding temperatures.The study demonstrates that our approach,which combines compositing with elemental doping and substitution,is effective in optimizing the thermoelectric performance of Sn Se at varied temperature ranges.
