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Structural components of the nuclear body in nuclei of Allium cepa cells

中国科学院地质与地球物理研究所2004学术年会

作者： MINGGUO zhai Key Laboratory of Mineral Resources,Institute of Geology & Geophysics,chinese academy of sciences,beijing,100029,china

The North china Craton(NCC) is a major Archaean craton,covering an area of c.300 000 km in north and northeast *** all Archaean rocks on the craton experienced high-grade metamorphism and strong migmatization,so that the preserved greenstone belts underwent granulite-amphibolite-facies metamorphism,anatectic melting and strong *** suggests that the NCC may have a more complicated early tectonic history than most other cratonic *** oldest NCC rocks are 3.8 Ga granitic gneisses in NE china and supracrustal rocks in eastern *** continental growth occurred at 2.9- 2.7 *** subsequent high-grade metamorphic events occurred at 2.6-2.45 Ga(’2.5 Ga event’) and 1.9-1.75 Ga(’1.8 Ga event’).The older episode is considered to mark an amalgamation event,whereas the 1.8 Ga event represents the final cratonization of the NCC. Some researchers have divided the 1.8 Ga event into a 1.9-1.8 Ga metamorphic event(interpreted as a continent-continent collision) followed by a 1.8-1.65 Ga rifting *** workers have suggested that the metamorphism and rifting could be parts of a single tectonic event related to Palaeo-Mesoproterozoic mantle *** general consensus on the NCC for the period 2.5-1.8 Ga is that the craton was then in an inactive ***, in this paper it is proposed that several Palaeoproterozoic mobile belts existed(showing many of the characteristics of Phanerozoic orogens).During the Mesoproterozoic-Neoproterozoic, a set of sedimentary sequences(the Changcheng-Jixian-Qingbaikou systems) constituted a disconformable-pseudoconformable succession within an intra-cratonic aulacogen. The signature of a 1.4-0.9 Ga orogen and the Rodinia breakup is very weak,indicating that the NCC did not experience major deformation as it was amalgamated into the Rodinia supercontinent.

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Cell Research 2001年第1期11卷 68-73页

作者： TAO WEI, CHANG HUI YAN, TAO CAI, SHUI HAO, ZHONG HE zhai (College of Life sciences, Peking University, beijing 100871, china) (Institute of Genetics and Cytology, Northeast Normal University, Changchun Jilin 130024, china) 1College of Life sciences Peking University Beijing 100871 China 1College of Life sciences Peking University Beijing 100871 China 1College of Life sciences Peking University Beijing 100871 China 2Institute of Genetics and Cytology Northeast Normal University Changchun Jilin 130024 China 1College of Life sciences Peking University Beijing 100871 China

Nuclear bodies have long been noted in interphase nuclei of plant cells, but their structural component, origin and fUnction are still unclear by now. The present work showed in onion cells the nuclear bodies appeared as a spherical structure about 0.3 to 0.8 μm in diameter. They possibly were formed in nucleolus and subsequently released, and entered into nucleoplasm. Observation through cytochemical staining method at the ultrastructural level codeined that nuclear bodies consisted of ribonucleoproteins (RNPs) and silver-stainable proteins. Immunocytochemical results revealed that nuclear bodies contained no DNA and ribosomal gene transcription factor (UBF). Based on these data, we suggested that nuclear bodies are not related to the ribosome or other gene transcription activities, instead they may act as subnuclear structures for RNPs transport from nucleolus to cytoplasm, and may also be involved in splicing of pre-mRNAs.

关键词： Nuclear body structural component ribonucleoproteins nucleolus Allium cepa.

Issues on china Regional Metallogeny

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Journal of Earth Science 2000年第3期19卷 26-33页

作者： zhai Yusheng Deng Jun Peng Runmin Faculty of Earth sciences and Mineral Resources, china University of Geosciencs, beijing 100083, china

According to geotectonic evolution and regional lithospheric features, the authors proposed six metallogenic domains in china: (1) Tianshan Xingmeng metallogenic domain, (2) Tarim North china metallogenic domain, (3) Qinling Qilian Kunlun metallogenic domain, (4) yangtze metallogenic domain, (5) South china metallogenic domain and (6) Himalaya Sanjiang metallogenic domain. In this paper, the authors also discuss, on the bases of geotectonic background and metallogenic evolutionary history, some metallogenic features of china: (1) A large percentage of ore formation occurred in paleo continental margins, including continental marginal rift and continental marginal accretionary orogenic belt. The majority of main mineral deposits are discovered on continental margins. (2) Superimposition of mineralization, favored the building up of giant and large mineral deposits, but often made the mineral deposits more complex in composition (associated components), morphology and structure. (3) Mineralization of crust derived anatectic granite is intensive and especially concentrated in the South china metallogenic domain. Mineralizations, including W, Sn and REE, are the products of long and mature development of W Sn polymetal rich earth crust in the metamorphic basement of South china Caledonian fold belt. (4) Epithermal ore forming system is well developed in the southwest part of yangtze continental block. Ore deposits of Hg, Sb, As, Au, Ag and U densely occur in sedimentary strata of the Late Paleozoic to Triassic. Ge, Tl, Te can also constitute independent ore deposits. (5) Ore formation caused by tectonic dynamic activities is distinctive. Small scale continental blocks of china display intensive activities, which played a widespread and diverse role in ore control. Junctions of faults, synchronous faults, shear zone structure and metamorphic core complex are main ore control structures. (6) The gold mineralization is complex and diversified. The greenstone

关键词： metallogenic domain metallogenic feature composite continental metallogenic system china.

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大尺度自成因机制与自成因地层学

地质学报 2024年第7期98卷 1977-2000页

作者：王俊辉 Tetsuji MUTO 鲜本忠油气资源与工程全国重点实验室中国石油大学(北京)北京102249 中国石油大学(北京)地球科学学院北京102249 长崎大学环境科学部日本长崎852-8521

在海平面升降、构造活动、沉积物供给等外部驱动作用下,沉积地层的叠置受自成因和他成因两种机制的控制。近年的认识表明,自成因机制可发生在沉积过程的各个时空尺度。不同于小尺度自成因机制仅发生在沉积系统的局部,大尺度自成因机制... 详细信息

在海平面升降、构造活动、沉积物供给等外部驱动作用下,沉积地层的叠置受自成因和他成因两种机制的控制。近年的认识表明,自成因机制可发生在沉积过程的各个时空尺度。不同于小尺度自成因机制仅发生在沉积系统的局部,大尺度自成因机制可在盆地范围内系统性地控制地层的发育,能够修饰甚至改变他成因过程。要想准确地探究地层的叠置样式与外部驱动条件之间的关系,必须有效地鉴别大尺度自成因与他成因过程。基于对大尺度自成因过程的认识,逐渐建立与发展了自成因地层学。它提出的自成因与他成因观、平衡响应与非平衡响应观为解析地层叠置样式与外部驱动条件之间的关系提供了新的视角。自成因地层学一方面对外部驱动条件分为稳定的(速率等作用方式保持不变)与不稳定的(速率等作用方式发生改变),由前者形成的地层叠加样式(或过程)称为自成因的,后者形成的地层叠加样式(或过程)称为他成因的。另一方面也将地层叠置样式分为稳定的(加积速率与进积速率的比值R_(agg)/R_(pro)保持不变)与不稳定的(R_(agg)/R_(pro)发生改变)。若稳定的外部驱动条件形成稳定的地层叠加样式,称为平衡响应,是自成因过程;稳定的外部驱动条件形成不稳定的地层叠加样式称为自成因的非平衡响应。此外,不稳定的外部驱动条件也可能形成稳定的地层叠加样式,称为他成因的非平衡响应。自成因地层学认为,由于自成因非平衡响应机制的普遍存在,地层的叠加过程通常表现得不稳定。相比而言,稳定的地层叠加样式仅在特殊情况下才能发生。传统成因地层学应当重视大尺度的自成因机制。

关键词：自成因地层学自成因与他成因平衡响应与非平衡响应海岸线自动后退三角洲海侵与非三角洲海侵基准面

PETROCHEMICAL CHARACTERISTICS AND TECTONIC SETTING OF THE GRAY GNEISSESIN NORTH DABIE TERRANE

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Scientia Geologica Sinica 1998年第4期 527-538页

作者： Zheng Xiangshen Jin Chengwei zhai Mingguo and Shi Yonghong(Institute of geology, chinese academy of sciences beijing 100029)

Gray gneiss is the principle component of the north Dabie metamorphic complex. On SiO2 variationdiagram most of major oxide display a smooth trend from tonalitic gneiss to trondhjemitic or granitic rocks,implying a magmatic differentiation model for the origin of the gray gneiss. Gray gneisses have lower ΣREE content with low grade fractionation of light REE/heavy REE. All rocks are enriched in large ionlithophile elements and depleted in high field strength elements and Nb. More basic rocks have highercontents of Cs, Ba, Rb and Sr and less depletion of Nb and Ti compared with meta-granitoids. Theincreasing of Nb depletion, the decreasing of Sr enrichment, and the transitional metal element Tibecoming greatly depleted with the increase of the SiO2 in rocks imply the fraction ofmafic minerals andplagioclase. Major element and trace element discriminations provide that the gray gneiss is of the calcalkaline association formed in a volcanic arc. The forming process of the gray gneiss is closely related to acollisional events. From the subduction before collision, through post-collision uplift, to late orogenicstage, the composition of the gray gneisses was evolving continuously. PetTochemical and geochemicalcharacteristics of the gray gneiss further strengthen the hypothesis that the Northern Dabie Terrain is apossible Andean-type arc.

关键词： Wang UHP Zhang PETROCHEMICAL CHARACTERISTICS AND TECTONIC SETTING OF THE GRAY GNEISSESIN NORTH DABIE TERRANE high

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量子计算系统软件研究综述

软件学报 2024年第1期35卷 1-18页

作者：谢磊翟季冬清华大学计算机科学与技术系北京100084

量子计算理论上有望解决诸多经典难解问题,近年来量子计算机的快速发展正推动这一理论进入实践.然而,当前硬件中繁多的错误会造成计算结果出错,严重限制了量子计算机解决实际问题的能力.量子计算系统软件位于应用与硬件之间,充分挖掘系... 详细信息

量子计算理论上有望解决诸多经典难解问题,近年来量子计算机的快速发展正推动这一理论进入实践.然而,当前硬件中繁多的错误会造成计算结果出错,严重限制了量子计算机解决实际问题的能力.量子计算系统软件位于应用与硬件之间,充分挖掘系统软件在硬件错误减缓方面的潜力,对于近期实现有实用价值的量子计算而言至关重要.由此,近期涌现了一批量子计算系统软件研究工作.将这些工作归纳入编译器、运行时系统和调试器3个范畴,通过对它们的分析总结,梳理量子计算系统软件的研究现状,揭示其在硬件错误减缓方面的重要作用.并对未来的研究方向进行展望.

关键词：量子计算系统软件嘈杂中规模量子编译运行时调试

亚麻籽油磷虾油软胶囊辅助降血脂作用人体试食研究

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食品与发酵工业 2024年第7期50卷 69-73页

作者：田世民翟磊陈建国杨彩玲杨溢中检科(北京)测试技术有限公司北京100123 中国检验检疫科学研究院综合检测中心北京100123 中国食品发酵工业研究院有限公司北京100015 天津市第三中心医院天津300170

为观察亚麻籽油磷虾油软胶囊对人体辅助降血脂的作用,将109例高脂血症者按血脂水平随机分为试食组和对照组。受试者不改变生活饮食习惯,试食组每日食用亚麻籽油磷虾油软胶囊2次,每次3粒,对照组采用空白对照。试验结果表明,试食组连续服... 详细信息

为观察亚麻籽油磷虾油软胶囊对人体辅助降血脂的作用,将109例高脂血症者按血脂水平随机分为试食组和对照组。受试者不改变生活饮食习惯,试食组每日食用亚麻籽油磷虾油软胶囊2次,每次3粒,对照组采用空白对照。试验结果表明,试食组连续服用亚麻籽油磷虾油软胶囊60 d后,未见不良反应。通过试食组与对照组间比较以及试食组自身前后比较分析发现,受试者血清中总胆固醇、甘油三酯和低密度脂蛋白胆固醇含量显著下降(P0.05)。试食组总有效率35.8%,高于对照组(1.9%)。因此,亚麻籽油磷虾油软胶囊对人体具有辅助降血脂的功能。

关键词：亚麻籽油磷虾油降血脂作用人体试食

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Approximation of functions on the Sobolev space with a Gaussian measure

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Science china Mathematics 2010年第2期53卷 373-384页

作者： WANG HePing 1, ZHANG YanWei 2 & zhai XueBo 1 1 School of Mathematical sciences, Capital Normal University, beijing 100048, china 2 Department of Mathematics, Zaozhuang University, Zaozhuang 277160, china 1. School of Mathematical sciences Capital Normal University Beijing 100048 China2. Department of Mathematics Zaozhuang University Zaozhuang 277160 China

We discuss the best approximation of periodic functions by trigonometric polynomials and the approximation by Fourier partial summation operators, Valle-Poussin operators, Ces`aro operators, Abel opera-tors, and Jackson operators, respectively, on the Sobolev space with a Gaussian measure and obtain the average error estimations. We show that, in the average case setting, the trigonometric polynomial subspaces are the asymptotically optimal subspaces in the L q space for 1≤q < ∞, and the Fourier partial summation operators and the Valle-Poussin operators are the asymptotically optimal linear operators and are as good as optimal nonlinear operators in the L q space for 1≤q < ∞.

关键词： average width best approximation approximation by linear operators Sobolev space Gaussian measure

An inducible CRISPR activation tool for accelerating plant regeneration

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Plant Communications 2024年第5期5卷 109-122页

作者： Cuimei Zhang Yajun Tang Shanjie Tang Lei Chen Tong Li Haidi Yuan Yujun Xu yangyan Zhou Shuaibin Zhang Jianli Wang Hongyu Wen Wenbo Jiang Yongzhen Pang Xian Deng Xiaofeng Cao junhui Zhou Xianwei Song Qikun Liu State Key Laboratory of Protein and Plant Gene Research School of Advanced Agricultural SciencesPeking UniversityBeijing 100871China Peking University Institute of Advanced Agricultural sciences Shandong Laboratory of Advanced Agricultural Sciences at WeifangShandong 261000China National Center for Plant Gene Research Institute of Genetics and Developmental BiologyChinese Academy of SciencesBeijing 100101China Grass and Science Institute of Heilongjiang academy of Agricultural sciences Heilongjiang 150086China Institute of Animal Science Chinese Academy of Agricultural SciencesBeijing 100193China Key Laboratory of Seed Innovation and National Center for Plant Gene Research Institute of Genetics and Developmental BiologyChinese Academy of SciencesBeijing 100101China

The inducible CRISPR activation(CRISPR-a)system offers unparalleled precision and versatility for regu-lating endogenous genes,making it highly sought after in plant *** this study,we developed a chem-ically inducible CRISPR-a tool for plants called ER-Tag by combining the LexA-VP16-ER inducible system with the SunTag CRISPR-a *** systematically compared different induction strategies and achieved high efficiency in target gene *** demonstrated that guide RNAs can be multiplexed and pooled for large-scale screening of effective morphogenic genes and gene pairs involved in plant *** experiments showed that induced activation of these morphogenic genes can accelerate regenera-tion and improve regeneration efficiency in both eudicot and monocot plants,including alfalfa,woodland strawberry,and *** study expands the CRISPR toolset in plants and provides a powerful new strategy for studying gene function when constitutive expression is not feasible or ideal.

关键词： inducible CRISPR activation morphogenic gene genetic transformation plant regeneration