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Flooding 1990s along the Yangtze River, has it concern of global warming?

Journal of Geographical Sciences 2001年第1期11卷 43-52页

作者： GONG Dao-yi1, ZHU Jin-hong2. WANG Shao-wu2.(1. Key Laboratory of Environmental Change and Natural Disaster, Institute of Resources Science, Beijing Normal university, Beijing 100875, China 2. Department of Geophysics, peking university, Beijing 100871, Key Laboratory of Environmental Change and Natural Disaster Institute of Resources Science Beijing Normal University Beijing China Department of Geophysics Peking University Beijing China

There were a series of severe floods along the middle to lower reaches of the Yangtze River (Changjiang River) in China during the 1990s. The extensive summer (June, July and August) precipitation is mostly responsible for the flooding. The summer rainfall in the 1980s and the 1990s is much higher than that in the previous 3 decades. The means for 1990–1999 is +87.62.mm above normal, marked the 1990s the wettest decade since the 1950s. Six stations with a time span of 1880–1999 are selected to establish century-long rainfall series. This series also shows that the 1990s is the wettest decade during the last 12. years. In the wettest 12.years, four occurred in the 1990s (1991, 1996, 1998 and 1999). Both global and China’s temperature show there is a relative lower air temperature during the 1960–1970s, and a rapid warming in the 1980–1990s. Comparisons of rainfall between 1960–1979 and 1980–1999 show there are dramatic changes. In the cold period 1960–1979, the summer rainfall along the Yangtze River is 3.8 % to 4.7 % below the normal, during the warm period 1980–1999, over 8.4 % to 18.2.% of summer rainfall occurs. Over the whole eastern China, the summer rainfall shows opposite spatial patterns from the 1960–1970s to 1980–1990s. The consistent trend toward more rainfall with global warming is also presented by the greenhouse scenario modeling. A millennial Drought/flood Index for the middle to lower reaches of the Yangtze River showed that although the surplus summer rainfall in the 1990s is the severest during the past 150 years, it is not outstanding in the context of past millennium. Power spectra of the Drought/flood Index show significant interdecadal periods at 33.3 and 11.8 years. Thus, both the natural interdecadal variations and the global warming may play important roles in the frequent floods witnessed during the last two decades.

关键词： summer rainfall Yangtze River global warming interdecadal variation

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补体相关性肾病诊断和治疗专家共识

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中华内科杂志 2024年第3期63卷 258-271页

作者：北京大学医学部肾脏病学系专家组赵明辉不详北京大学第一医院肾内科、北京大学肾脏病研究所北京100034

随着补体系统在各类肾脏疾病中的作用机制逐渐阐明,针对补体活化不同环节的药物相继出现,部分已应用于临床。但补体靶向治疗仍存在诸多问题。北京大学医学系补体相关性肾病诊断和治疗专家共识协作组在国内外肾脏疾病指南/共识的基础上,... 详细信息

随着补体系统在各类肾脏疾病中的作用机制逐渐阐明,针对补体活化不同环节的药物相继出现,部分已应用于临床。但补体靶向治疗仍存在诸多问题。北京大学医学系补体相关性肾病诊断和治疗专家共识协作组在国内外肾脏疾病指南/共识的基础上,结合最新证据制定了本共识,简述了补体相关性肾病的发病机制、诊断思路、补体靶向治疗与特殊致病微生物的疫苗免疫等方面的最新证据和建议,为补体相关性肾病的诊断和治疗提供参考。

关键词：补体相关性肾病诊断治疗补体抑制剂

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Discovery and character of the Kunlun-Yellow River Movement

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Chinese Science Bulletin 1998年第10期43卷 833-836页

作者： CUI Zhijiu 1, WU Yongqiu 2.3 and LIU Gengnian 1 1. Department of Geography, peking university, Beijing 100871, China 2. Open Research Laboratory of Environmental Changes and Natural Disaster of State Education Commission, Beijing 100875, China Department of Geography Peking University Beijing China Open Research Laboratory of Environmental Changes and Natural Disaster of State Education Commission Beijing China Department of Geography Sichuan Normal Uni-versity Chengdu China

Based on geomorphological, tectonic and sedimentary data, a Kunlun Yellow River Tectonic Movement has been recognized in 1 10-0 60 Ma B.P. This tectonic movement, which leads to uplift of the Qinghai_Xizang (Tibet) Plateau from 1 500 to 3 000-3 500 m, is periodic, abrupt and changeable in the movement rate of uplifting and slide slipping.

关键词： Kunlun Mountain Pass 700 kaB.P. tectonic movement.

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The General Characteristics and Distribution of the Glaucophane-Schist Belts of China

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Acta Geologica Sinica(English Edition) 1990年第1期64卷 101-114页

作者： Dong Shenbao Dong Shenbao Department of Geology, peking university, Beijing Department of Geology Peking University Beijing

On the basis of the temperature variation, the glaucophane-schist facies Gan be classified into two faciesgroups, the glaucophane-lawsonite facies group and the glaucophane-greenschist facies group, and forms vari-ous facies series with other metamorphic facies. Glaucophane-schist belts of China are of different types withregard to their average T-P gradients and tectonic environments. They are: (1) Proterozoic intracratonicglaucophane-schist belts, (2. Caledonian intracratonic glaucophane-schist belts, (3) Palaeozoic pericratonicglaucophane-schist belts along the northern margin of the Chinese Platform, and (4) Meso-Cenozoicglaucophane-schist belts related to subduction. The initiation and evolution of glaucophane-schist metamorphism are related to their tectonic environ-ments. Most glaucophane-schist belts of China were formed in sialic environments. first the crust began tobreak up and eventually oceanic crust was formed. It seems that a non-uniformitarian mechanism may be in-volved as this evolution is related to the change of the configuration of the heat flow within the crust.

关键词： meta ab The General Characteristics and Distribution of the Glaucophane-Schist Belts of China

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Progress of Lyman-alpha-based beam emission spectroscopy(Ly BES)diagnostic on the HL-2. tokamak

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Plasma Science and Technology 2024年第3期26卷 118-125页

作者：周艺轩余羿许敏柯锐聂林徐皓赵光义刘灏袁子豪肖晨雨李继全肖池阶 the HL-2. Team Southwestern Institute of Physics Chengdu 610041People's Republic of China Sino-French Institute of Nuclear Engineering and Technology Sun Yat-sen UniversityZhuhai 519082People's Republic of China State Key Laboratory of Nuclear Physics and Technology School of PhysicsPeking UniversityBeijing 100871People's Republic of China

An edge Lyman-alpha-based beam emission spectroscopy(LyBES)diagnostic,using a heating NBI(neutral beam injection)system,is currently under development on the HL-2. *** 2.-channel edge LyBES,which is intended to measure the density fluctuation in plasma edge(from R=1960 mm to R=2.2. mm)with an improved spatial resolution of 3.3 mm,is a complement to the existing conventional beam emission spectroscopy(BES)*** this article,we introduce the progress of LyBES diagnostic,including the collection optics,the monochromator,and the detector *** reflectance of the collection mirrors is measured to be~82.at 12. nm,and the aberration geometrical radius of the collection optics is tested to be~150μm in the aimed *** linear dispersion of the LyBES monochromator is designed to be~0.09 nm mm^(-1).The bandwidth of the detector system with the 5×10^(7)V A^(-1)preamplifier gain is measured to be~2.0 kHz,and the peak-to-peak noise of the detector system is tested to be~16 *** finalized design,components development and testing of the LyBES diagnostic have been completed at present,and an overall performance of the LyBES diagnostic is to be confirmed in the next HL-2. campaign.

关键词： density fluctuation Ly BES BES vacuum ultraviolet

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BRILL-NOETHER MATRIX FOR RANK TWO VECTOR BUNDLES

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Chinese Annals of Mathematics,Series B 2002年第4期23卷 531-538页

作者： TAN XIAOJIANGSchool of Mathematical Sciences, peking university, Beijing 100871, China School of Mathematical Sciences Peking University Beijing 100871 China

Let X be an arbitrary smooth irreducible complex projective curve, E (?)X a rank two vector bundle generated by its sections. The author first represents ?as a triple {D1,D2.f}, where D1 , D2.are two effective divisors with d = deg(D1) + deg(D2., and f ∈ H?X, [D1] |D2. is a. collection of polynomials. E is the extension of [D2. by [D1] which is determined by f. By using / and the Brill-Noether matrix of D1+D2. the author constructs a 2. × d matrix WE whose zero space gives Im{H0(X,[D1]) (?) H0(X, [D1] |D1)}(?) Im{H?X, E) (?) H0(X,[D2.) (?) H0(X, [D2.|D2.} From this and H0(X,E) = H0(X,[D1]) (?)Im{H0(X,E) (?) H0(X, [D2.)}, it is got in particular that dimH0(X, E) = deg(E) - rank(WE) + 2.

关键词： Brill-Noether matrix Vector bundle Effective divisor

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In vitro reassembly of nuclear envelopes and organelles in Xenopus egg extracts

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Cell Research 2006年第07期16卷 632-640页

作者： Ping Lu~1 Hui Zheng~2.Zhonghe Zhai ~1College of Life Sciences ~2.nstitute of Molecular Medicine,peking university Beijing 100871,China CollegeofLifeSciences InstituteofMolecularMedicine PekingUniversityBeijing100871China

We reconstituted bilayer nuclear membranes,multilayer membranes,and organelles from mixtures of Xenopus laevis eggextracts and demembranated Xenopus sperm *** proportions of the cytosolic and vesicular fractions from theeggs were used in the reconstitution mixtures.A cytosol:vesicle ratio of 10:1 promoted reassembly of the normal bilayernuclear membrane with inserted nuclear pore complexes around the decondensed Xenopus sperm chromatin.A cytosol:vesicle ratio of 5:1 caused decondensed and dispersed sperm chromatin to be either surrounded by or divided by unusualmultilayer membrane structures with inlaid pore complexes.A cytosol:vesicle ratio of 2.5:1 promoted reconstitution ofmitochondria,endoplasmic reticulum networks,and Golgi *** reassembly of the endoplasmic reticulumand Golgi apparatus,vesicular fragments of the corresponding organelles fused together and changed their shape to formflattened cisternae,which were then stacked one on top of another.

关键词： cell-free system endoplasmic reticulum Golgi apparatus mitochondria nuclear reconstitution Xenopus egg extracts

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A software architecture centric self-adaptation approach for Internetware

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Science in China(Series F) 2008年第6期51卷 722-742页

作者： MEI Hong1,2. HUANG Gang1,2. LAN Ling1,2.& LI JunGuo1,2.1 Key Laboratory of High Confidence Software Technologies (peking university), Ministry of Education, Beijing 100871, China 2.School of Electronics Engineering and Computer Science, peking university, Beijing 100871, China Key Laboratory of High Confidence Software Technologies (peking university) Ministry of Education Beijing China School of Electronics Engineering and Computer Science Peking University Beijing China

Being one of the basic features of Internetware, self-adaptation means that the software system can monitor its runtime state and behavior and adjust them when necessary according to pre-defined policies. Focusing on the three fundamental issues of self-adaptation, including the scope, operability and trustworthiness, a software architecture （SA） centric approach for Internetware＇s self-adaptation is presented in this paper. All of the self-adaptive actions, i.e. monitoring, analyzing, planning and executing, are performed based on SA. In detail, runtime state and behavior of Internetware are represented and changed in the form of runtime soft- ware architecture. The knowledge for self-adaptation is captured, organized and reasoned in the form of SA so that automatic analysis and decision-making are achieved.

关键词： Internetware self-adaptation software architecture middleware

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A community-centric approach to automated service composition

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Science China(Information Sciences) 2010年第1期53卷 50-63页

作者： LIU XuanZhe1,2. HUANG Gang1,2.& MEI Hong1,2.1School of Electronics Engineering and Computer Science, peking university, Beijing 100871, China 2.ey Laboratory of High Confidence Software Technologies, Ministry of Education, peking university, Beijing 100871, China School of Electronics Engineering and Computer Science Peking University Beijing China Key Laboratory of High Confidence Software Technologies Ministry of Education Peking University Beijing China

In the recent years, the web has kept growing rapidly and undergone tremendous changes towards a user-centric environment. With the proliferation of services available on the Internet, millions of users are able to voluntarily participate in and collaborate for their own interests and benefits by means of service composition. However, due to the ever increasing number of services, it then becomes a challenging issue to enable the users to rapidly select and compose the proper services. In this paper, we propose an approach which utilizes service communities for automated service composition. This paper makes three contributions. firstly, we propose the service community architecture and identify two key components to facilitate service discovery and composition. Secondly, assisted by the service community, we provide two composition types to help users explore the space of potential composition opportunities without having to understand too many details of individual candidate services. Finally, we evaluate our approach by performance analysis and provide a web-based prototype that lowers the entry barrier for the users.

关键词： services computing service composition service community

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Rat adipose-derived stromal cells expressing BMP4 induce ectopic bone formation in vitro and in vivo

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Acta Pharmacologica Sinica 2006年第12期27卷 1608-1615页

作者： Lin LIN~2.Xin FU~2.Xin ZHANG~2.Lian-xu CHEN~2.Ji-ying ZHANG~2.Chang-long YU~(2.4)Kang-tao MA~3 Chun-yan ZHOU~(3,4)2.Institute of Sports Medicine,peking university Third Hospital,Beijing 100083,China 3 Department of Biochemistry and Molecular Biology,peking university School of Basic Medical Science,Beijing 100083,China Institute of Sports Medicine Peking University Third Hospital Beijing 100083 China.

Aim:Bone morphogenetic protein 4(BMP4)is one of the main local contributingfactors in callus formation in the early phase of fracture ***-derivedstromal cells(ADSC)are multipotent *** present study was conducted toinvestigate the osteogenic potential of ADSC when exposed to adenovirus con-taining BMP4 cDNA(Ad-BMP4).Methods:ADSC were harvested from Sprague-Dawley *** exposure to Ad-BMP4,ADSC were assessed by alkaline phos-phatase activity(ALP)assay,RT-PCR and yon Kossa ***4 expressionwas assessed by RT-PCR,immunofluorescence and Western blot analysis,ADSCtransduced with Ad-BMP4 were directly injected into the hind limb muscles ofathyrnic *** Ad-EGFP(enhanced green fluorescence protein)served *** animals were examined by X-ray film and histological ***:The expression of BMP4 was confirmed at both mRNA and protein *** expression of the osteoblastic gene,ALP activity and yon Kossa stainingconfirmed that ADSC transduced with Ad-BMP4 underwent rapid and markedosteoblast differentiation,whereas ADSC transduced with Ad-EGFP and cells leftalone displayed no osteogenic differentiation.X-ray and histological examinationconfirmed new bone formation in athymic mice transplanted with ADSC trans-duced with ***:Our data demonstrated successful osteo-genic differentiation of ADSC transduced with Ad-BMP4 in vitro and in *** may be an ideal source of mesenchyme lineage stem cells for gene therapyand tissue engineering.

关键词： adipose-derived stromal cells BMP4 gene therapy bone formation

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