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Explaining the “Pulse of Protoplasm”: The search for molecular mechanisms of protoplasmic streaming

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Journal of Integrative Plant Biology 2015年第1期57卷 14-22页

作者： Michael R.Dietrich Department of biological sciences Dartmouth College

Explanations for protoplasmic streaming began with appeals to contraction in the eighteenth century and ended with appeals to contraction in the twentieth. During the intervening years, biologists proposed a diverse array of mechanisms for streaming motions. This paper focuses on the re-emergence of contraction among the molecular mecha-nisms proposed for protoplasmic streaming during the twentieth century. The revival of contraction is a result of a broader transition from colloidal chemistry to a macro- molecular approach to the chemistry of proteins, the recognition of the phenomena of shuttle streaming and the pulse of protoplasm, and the influential analogy between protoplasmic streaming and muscle contraction.

关键词： Actin cytoplasmic streaming history of cell biology protoplasm

Sporophytic nondisjunction of the maize B chromosome at high copy numbers

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Journal of Genetics and Genomics 2010年第1期37卷 79-84页

作者： Rick E.Masonbrink James A.Birchler Division of biological sciences University of Missouri

It has been known for decades that the maize B chromosome undergoes nondisjunction at the second pollen *** in-situ hybridization （FISH） was used to undertake a quantitative study of maize plants with differing numbers of B chromosomes to observe if instability increases by increasing B dosage in root tip tissue.B chromosome nondisjunction was basically absent at low copy number,but increased at higher B ***,B nondisjunction rates are dependent on the dosage of B＇s in the *** in nondisjunction were also documented between odd and even doses of the *** plants that have inherited odd numbered doses of the B chromosome,B loss is nearly twice as likely as B gain in a somatic *** comparing plants with even doses of B＇s to plants with odd doses of B＇s,plants with even numbers had a significantly higher chance to increase in ***,the B＇s nondisjunctive capacity,previously thought to be primarily restricted to the gametophyte,is present in sporophytic cells.

关键词： maize Zea mays B chromosome nondisjunction odd-even effect

Inaccuracies in the history of a well-known introduction:a case study of the Australian House Sparrow(Passer domesticus)

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Chinese Birds 2016年第2期7卷 95-109页

作者： Samuel C.Andrew Simon C.Griffith Department of biological sciences Macquarie University

Background:Modern ecosystems contain many invasive species as a result of the activity of acclimatisation societies that operated in the second half of the nineteenth century,and these species provide good opportunities for studying invasion ***,to gain insight into the ecological and genetic mechanisms that determine the rate of colonization and adaptation to new environments,we need a good understanding of the history of the introduced species,and a knowledge of the source population,timing,and number of individuals introduced is particularly ***,any inaccuracies in the history of an introduction will affect subsequent assumptions and ***:Focusing on a single well-known species,the House Sparrow(Passer domesticus),we have documented the introduction into Australia using primary sources(*** records and newspaper articles).Results:Our revised history differs in a number of significant ways from previous *** evidence indicates that the House Sparrow was not solely introduced from source populations in England but also from Germany and most strikingly also from India—with the latter birds belonging to a different *** also clarify the distinction between the number released and the number of founders,due to pre-release captive breeding programs,as well as identifying inaccuracies in a couple of well-cited sources with respect to the range expansion of the introduced ***:Our work suggests that caution is required for those studying introductions using the key sources of historical information and ideally should review original sources of information to verify the accuracy of published accounts.

关键词： Acclimatisation Bottlenecks Propagule size Range expansion Hybridisation

Progressive heterosis in genetically defined tetraploid maize

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Journal of Genetics and Genomics 2019年第8期46卷 389-396页

作者： Jacob D.Washburn Mitchell J.McElfresh James A.Birchler Division of biological sciences University of Missouri

Progressive heterosis, i.e., the additional hybrid vigor in double-cross tetraploid hybrids not found in their single-cross tetraploid parents, has been documented in a number of species including alfalfa,potato, and maize. In this study, four artificially induced maize tetraploids, directly derived from standard inbred lines, were crossed in pairs to create two single-cross hybrids. These hybrids were then crossed to create double-cross hybrids containing genetic material from all four original lines. Replicated fieldbased phenotyping of the materials over four years indicated a strong progressive heterosis phenotype in tetraploids but not in their diploid counterparts. In particular, the above ground dry weight phenotype of double-cross tetraploid hybrids was on average 34% and 56% heavier than that of the single-cross tetraploid hybrids and the double-cross diploid counterparts, respectively. Additionally,whole-genome resequencing of the original inbred lines and further analysis of these data did not show the expected spectrum of alleles to explain tetraploid progressive heterosis under the complementation of complete recessive model. These results underscore the reality of the progressive heterosis phenotype,its potential utility for increasing crop biomass production, and the need for exploring alternative hypothesis to explain it at a molecular level.

关键词： Maize Tetraploid Heterosis Dominance complementation Progressive heterosis

Improving the accuracy of pose prediction in molecular docking via structural fltering and conformational clustering

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Chinese Chemical Letters 2013年第11期24卷 1001-1004页

作者： Shi-Ming Peng Yu Zhou Niu Huang College of biological sciences China Agricultural University National Institute of biological sciences College of Life sciences Beijing Normal University

Structure-based virtual screening（molecular docking）is now one of the most pragmatic techniques to leverage target structure for ligand *** binding pose prediction is critical to molecular ***,we describe a general strategy to improve the accuracy of docking pose prediction by implementing the structural descriptor-based fltering and KGS-penalty function-based conformational clustering in an unbiased *** assessed our method against 150 high-quality protein–ligand complex ***,such simple components are suffcient to improve the accuracy of docking pose *** success rate of predicting near-native docking pose increased from 53%of the targets to 78%.We expect that our strategy may have general usage in improving currently available molecular docking programs.

关键词： Molecular docking Pose prediction Structural descriptor Conformational clustering

Spatial analysis of plant detritus processing in a Mediterranean River type: the case of the River Tirso Basin, Sardinia, Italy

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Journal of Environmental sciences 2003年第2期15卷 227-240页

作者： Maurizio Pinna Franca Sangiorgio Alessio Fonnesu Alberto Basset Department of biological and Environmental sciences and Technologies University of LecceDepartment of Biological and Environmental Sciences and Technologies University of LecceDepartment of Biological and Environmental Sciences and Technologies University of LecceDepartment of Biological and Environmental Sciences and Technologies University of Lecce 73100 Lecce Italy73100 Lecce Italy73100 Lecce Italy73100 Lecce Italy

The river continuum concept represents the most general framework addressing the spatial variation of both structure and function in river ecosystems. In the Mediterranean ecoregion, summer drought events and dams constitute the main sources of local disturbance to the structure and functioning of river ecosystems occurring in the river basin. In this study, we analysed patterns of spatial variation of detritus processing in a 7th order river of the Mediterranean ecoregion(River Tirso, Sardinia-Italy) and in three 4th order sub-basins which were exposed to different summer drought pressures. The study was carried out on Phragmites australis and Alnus glutinosa leaf detritus at 31 field sites in seasonal field experiment Detritus processing rates were higher for Alnus glutinosa than for Phragmites australis plant detritus. Processing rates of Alnus glutinosa leaves varied among seasons and study sites from 0.006 d -1 to 0.189 d -1 and those of Phragmites australis leaves ranged from 0.0008 d -1 to 0.102 d -1, with the lowest values occurring at sites exposed to summer drought. Seasons and sites accounted for a significant proportion of such variability. Alder detritus decay rates generally decreased with increasing stream order, while reed detritus decay rates generally increased on the same spatial gradient. Summer drought events affected these spatial patterns of variation by influencing significantly the decay rates of both plant detritus. The comparisons among and within sub-basins showed strong negative influence of summer drought on detritus processing rates. Similarly, in the entire River Tirso basin decay rates were always lower at disturbed than at undisturbed sites for each stream order; decay rates of reed detritus remained lower at those sites even after the end of the disturbance events, while alder decay rates recovered rapidly from the summer drought perturbations. The different recovery of the processing rates of the two leaves could also

关键词： ecosystem processes spatial patterns disturbance Mediterranean ecosystem type

ATP translocation and chloroplast biology

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National Science Review 2019年第6期6卷 1073-1076页

作者： Chia P.Voon Boon L.Lim School of biological sciences University of Hong Kong

By studying changes in ATP levels in the plastids and cytosol of live plants using a Mg ATP2-specific F?rster resonance energy transfer（FRET）-based sensor, the entry of cytosolic ATP to the mature chloroplasts of Ar... 详细信息

关键词： ATP translocation and chloroplast biology

Einstein Probe discovery of EP240408a: A peculiar X-ray transient with an intermediate timescale

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Science China(Physics,Mechanics & Astronomy) 2025年第1期Mechanics & Astronomy) .卷 222-240页

作者： Wenda Zhang Weimin Yuan Zhixing Ling Yong Chen Nanda Rea Arne Rau Zhiming Cai Huaqing Cheng Francesco Coti Zelati Lixin Dai Jingwei Hu Shumei Jia Chichuan Jin Dongyue Li Paul O’Brien Rongfeng Shen Xinwen Shu Shengli Sun Xiaojin Sun Xiaofeng Wang Lei Yang Bing Zhang Chen Zhang Shuang-Nan Zhang Yonghe Zhang Jie An David Buckley Alexis Coleiro Bertrand Cordier Liming Dou Rob Eyles-Ferris Zhou Fan Hua Feng Shaoyu Fu Johan P.U.Fynbo Lluis Galbany Saurabh W.Jha Shuaiqing Jiang Albert Kong Erik Kuulkers Weihua Lei Wenxiong Li Bifang Liu Mingjun Liu Xing Liu Yuan Liu Zhu Liu Chandreyee Maitra Alessio Marino Itumeleng Monageng Kirpal Nandra Jeremy Sanders Roberto Soria Lian Tao Junfeng Wang Song Wang Tinggui Wang Zhongxiang Wang Qingwen Wu Xuefeng Wu Dong Xu Yanjun Xu Suijian Xue Yongquan Xue Zijian Zhang Zipei Zhu Hu Zou Congying Bao Fansheng Chen Houlei Chen Tianxiang Chen Wei Chen Yehai Chen Yifan Chen Chenzhou Cui Weiwei Cui Yanfeng Dai Dongwei Fan Ju Guan Dawei Han Dongjie Hou Haibo Hu Maohai Huang Jia Huo Zhenqing Jia Bowen Jiang Ge Jin Chengkui Li Junfei Li Longhui Li Maoshun Li Wei Li Zhengda Li Tianying Lian Congzhan Liu Heyang Liu Huaqiu Liu Fangjun Lu Laidan Luo Jia Ma Xuan Mao Haiwu Pan Xin Pan Liming Song Hui Sun Yunyin Tan Qingjun Tang Yihan Tao Hao Wang Juan Wang Lei Wang Wenxin Wang Yilong Wang Yusa Wang Qinyu Wu Haitao Xu Jingjing Xu Xinpeng Xu Yunfei Xu Zhao Xu Changbin Xue Yulong Xue Ailiang Yan Haonan Yang Xiongtao Yang Yanji Yang Juan Zhang Mo Zhang Wenjie Zhang Zhen Zhang Zhen Zhang Ziliang Zhang Donghua Zhao Haisheng Zhao Xiaofan Zhao Zijian Zhao Hongyan Zhou Yilin Zhou Yuxuan Zhu Zhencai Zhu National Astronomical Observatories Chinese Academy of sciences School of Astronomy and Space sciences University of Chinese Academy of sciences Key Laboratory of Particle Astrophysics Institute of High Energy Physics Chinese Academy of sciences Institute of Space sciences (ICE) CSIC Institut d’Estudis Espacials de Catalunya (IEEC) Max Planck Institute for Extraterrestrial Physics Innovation Academy for Microsatellites Chinese Academy of sciences Department of Physics University of Hong Kong School of Physics and Astronomy University of Leicester School of Physics and Astronomy Sun Yat-sen University Department of Physics Anhui Normal University Shanghai Institute of Technical Physics Chinese Academy of sciences Physics Department Tsinghua University Nevada Center for Astrophysics University of Nevada Las Vegas Department of Physics and Astronomy University of Nevada Las Vegas South African Astronomical Observatory Department of Astronomy University of Cape Town Department of Physics University of the Free State Université Paris Cité CNRS Astroparticule et Cosmologie Université Paris Cité CEA Paris-Saclay IRFU/DAp-AIM Department of Astronomy Guangzhou University Cosmic Dawn Center (DAWN) Niels Bohr Institute University of Copenhagen Department of Physics and Astronomy Rutgers the State University of New Jersey Institute for Cosmic Ray Research The University of Tokyo ESA/ESTEC Department of Astronomy School of Physics Huazhong University of Science and Technology INAF-Osservatorio Astrofisico di Torino Sydney Institute for Astronomy School of Physics The University of Sydney Department of Astronomy Xiamen University Institute for Frontiers in Astronomy and Astrophysics Beijing Normal University Department of Astronomy University of Science and Technology School of Astronomy and Space sciences University of Science and Technology of China Institute of Deep Space sciences Deep Space Exploration Laboratory Department of Astronomy School of Physics and Astronomy Yunnan University Shanghai Astronomical Observatory Chi

We report the discovery of a peculiar X-ray transient,EP240408a,by Einstein Probe （EP） and follow-up studies made with EP,Swift,NICER,GROND,ATCA and other ground-based multiwavelength *** new transient was first detected with Wide-field X-ray Telescope （WXT） on board EP on April 8th,2024,manifested in an intense yet brief X-ray flare lasting for *** flare reached a peak flux of 3.9×10-9erg cm-2s-1in 0.5-4 ke V,～300 times brighter than the underlying X-ray emission detected throughout the *** and more precise follow-up observations by EP/FXT,Swift and NICER confirmed the finding of this new *** X-ray spectrum is non-thermal in 0.5-10 ke V,with a power-law photon index varying *** X-ray light curve shows a plateau lasting for ～4 d,followed by a steep decay till becoming undetectable ～10 d after the initial *** on its temporal property and constraints from previous EP observations,an unusual timescale in the range of 7-23 d is found for EP240408a,which is intermediate between the commonly found fast and long-term *** counterparts have been found in optical and near-infrared,with the earliest observation at 17 h after the initial X-ray detection,suggestive of intrinsically weak emission in these *** demonstrate that the remarkable properties of EP240408a are inconsistent with any of the transient types known so far,by comparison with,in particular,jetted tidal disruption events,gamma-ray bursts,X-ray binaries and fast blue optical *** nature of EP240408a thus remains an *** suggest that EP240408a may represent a new type of transients with intermediate timescales of the order of～10 *** detection and follow-ups of more of such objects are essential for revealing their origin.

关键词： X-ray transients ${\bm~{Einstein~~Probe}}$

Molecular signature of chilling adaptation in rice

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National Science Review 2016年第3期3卷 276-277页

作者： Xin-Min Li Hong-Xuan Lin Shanghai Institutes for biological sciences Chinese Academy of Sciences

Originating from the wild species(Oryza rufipogon),Asian rice cultivars(***) mainly domesticated into two major subspecies,indica and japonica,after～10 000 years[1].This progress involving genetic variation,artificial selection and local adaptation stands for a footstone for the development of human *** meet the need of human civilization expansion,rice spreads to wider and wider areas with different

关键词： RGA Molecular signature of chilling adaptation in rice ABA RGS