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Age of Yingfeng rapakivi granite pluton on the north flank of Qaidam and its geological significance

Science china Earth Sciences 2004年第4期47卷 357-365页

作者： XIAO Qinghui1,2, LU Xinxiang1,3. WANG Fei4. SUN Yangui5, WEI Xiangdong3.& XING Zuoyun6 1. Division of Granite Geology, china Geological Survey, Yichang 4.3.03. china 2. information {3. of Ministry of Land and Resources, Beijing 100812, china 3. Geological Survey of Henan Province and Institute of Geological Research of Henan Province, Zhengzhou 4.0053. china 4. Geological Institute, china Seismological Bureau, Beijing 100029, china 5. Geological Survey Institute of Qinghai Province, Xining 81003., china 6. china university of Geosciences, Wuhan 4.0}074. china Division of Granite Geology China Geological Survey Yichang China information center of Ministry of Land and Resources Beijing China Geological Survey of Henan Province and Institute of Geological Research of Henan Province Zhengzhou China Geological Institute China Seismological Bureau Beijing China Geological Survey Institute of Qinghai Province Xining China china university of Geosciences Wuhan China

The Yingfeng rapakivi granite on the north flank of Qaidam is a newly discovered Proterozoic rapakivi pluton in china, which was found after the discovery of Shachang rapakivi in Miyun County, Beijing and Kuandian rapakivi in Jilin Province. Yingfeng rapakivi pluton is ex-posed on the north side of the suture belt between Qinling-Kunlun orogenic belt and North china plate. U-Pb zircon isotopic dating and Ar-Ar isotopic dating of both hornblende and K-feldspar from the Yingfeng rapakivi granite have been conducted. The results show that the age of (1776±3.)Ma at the upper intercept in Concorde diagram represents the age of formation of the plu-ton, whereas the age of (526 281) Ma at the lower intercept and Ar-Ar mineral dating of horn-blende and K-feldspar correspond to the age of a later event affecting the pluton, suggesting that Yingfeng pluton has ever been affected by strong regional Caledonian-Hercynian tectonic movement after its formation. The discovery of middle Proterozoic Yingfeng rapakivi granite pro-vides a petrologic evidence for the timing of cratonization of both the continental crust basement in western china and the basement of the North china plate and for a rifting event taking place in the mid-Proterozoic, suggesting that an amalgamation of ancient china continents had ever happened during the L liang Movement?between the early Proterozoic and the mid-Proterozoic.

关键词： rapakivi, U-Pb dating, Ar-Ar dating, Kunlun-Qinling orogenic belt.

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3. building modeling,organization and application in digital city system

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中国科学：技术科学英文版 2010年第S1期53卷 134-142页

作者： YANG Xue 1,WENG JingNong 1,2,XIA YuBin 2,WU Lun 3.& SUI ZhengWei 3.1 College of Software,Beihang university,Beijing 100191,china 2 College of Computer,Beihang university,Beijing 100191,china 3.Institute of Remote Sensing and GIS,peking university,Beijing 100871,china College of Software Beihang University Beijing China College of Computer Beihang University Beijing China Institute of Remote Sensing and GIS Peking University Beijing China

The real world is a three-dimensional(3.)space requiring that 3. geospatial information applications be developed in alignment with the observer’s visual and perceptive ***,3. building model data are required in a wide range of areas such as urban planning,environmental protection,real estate management and emergency *** the same time,the development of Web service[LU1]technologies allows the possibility of the widely distributed 3. geospatial data on the web.3. city building model with its related information is an important part in the construction of a digital city system,and has become a staple resource on the web *** view of the hierarchical representation of a 3. building model,an abstract of a 3. building model based on structure details is studied,and a novel representation approach named 3. transparent building hierarchical model is presented in this *** approach fully uses both the existing 3. modeling technologies and CAD constructing mapping *** the spatial relationship description,structural components inside a building can be represented and integrated as hierarchical models in a unified 3. *** addition,based on the characteristics of the 3. building model data,a service-oriented architecture and Web service technologies for 3. city building models are *** aim of the approach is that 3. city building models can be used as a kind of data resource service on the web,and can also exist independently in various different web applications.

关键词： 3. modeling 3. transparent building hierarchical models china Star web services

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Another ID-Based Proxy Signature Scheme and Its Extension

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Wuhan university Journal of Natural Sciences 2007年第1期12卷 33-36页

作者： ZHANG Jianhong1,2 , ZOU Wei3.1. College of Science, North china university of Technology, Beijing 10004.,china 2. Institute of Software of Chinese Academy of Sciences /State Key Laboratory of {3. Security, Beijing 100080, china 3. Institute of Computer Science and Technology, peking university, Beijing 100871, china College of Science North China University of Technology Beijing China State Key Laboratory of information Security Institute of Software of Chinese Academy of Sciences Beijing China Institute of Computer Science and Technology Peking University Beijing China

So fur, the security of many proxy signatures has seldom been considered in a formal way and most of them cannot satisfy nonepudiation. In this work, a novel ID-based （Identity-based） proxy signature scheme is proposed by combining the proxy signature with ID-based public cryptography, and they formalize the notion of security for ID-based proxy signature schemes. And show that the security of the proposed scheme is secure. Compured with other proxy signature schemes, it does not need a secure channel. Thus, it is particularly suitable for the unreliable network computation environment. Finally, they extend proposed scheme to a proxy multi-signature which has the following advantages （1） the size of proxy multi- signature is independent of the number of delegating users; （2） the computation cost of proxy multi-signature only need two Weil paring.

关键词： proxy signature multisignature security proof

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Hydrogen sulfide ameliorates vascular calcification induced by vitamin D3.plus nicotine in rats

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Acta Pharmacologica Sinica 2006年第3期27卷 299-306页

作者： Sheng-ying WU~(2,6) Chun-shui PAN~3.Bin GENG~3.Jing ZHAO~3.Fang YU~3.Yong-zheng PANG~3.Chao-shu TANG~4.Yong-fen QI~(3.4.5) ~2Institute of Cardiovascular Disease,peking university First Hospital.Beijing 10003. ~3.epartment of Physiology and Pathophysiology,peking university Health Science center,Beijing 100083.{14.,~4.ey Laboratory of Molecular Cardiovascular Science,Ministry of Education,Beijing 100083.{14. 2Institute of Cardiovascular Disease Peking University First Hospital Beijing 100034 China 3.epartment of Physiology and Pathophysiology Peking University Health Science Center Beijing 100083 China 3.epartment of Physiology and Pathophysiology Peking University Health Science Center Beijing 100083 China 3.epartment of Physiology and Pathophysiology Peking University Health Science Center Beijing 100083 China 3.epartment of Physiology and Pathophysiology Peking University Health Science Center Beijing 100083 China 3.epartment of Physiology and Pathophysiology Peking University Health Science Center Beijing 100083 China 4.ey Laboratory of Molecular Cardiovascular Science Ministry of Education Beijing 100083 China 4.ey Laboratory of Molecular Cardiovascular Science Ministry of Education Beijing 100083 China

Aim:To investigate the role of the endogenous cystathionine γ-synthase(CSE)/hydrogen sulfide(H2S)pathway in vascular calcification in ***:A ratvascular calcification model was established by administration of vitamin D3.plusnicotine(VDN).The amount of CSE and osteopontin(OPN)mRNA was deter-mined by using semi-quantitative reverse-transcription polymerase chain *** calcium content,4.Ca2+accumulation and alkaline phosphatase(ALP)activitywere measured.H,S production and CSE activity were ***:yonKossa staining produced strong positive black/brown staining in areas amongthe elastic fibers of the medial layer in the calcified *** calcium content,4.Ca2+accumulation and ALP activity in calcified arteries increased by 6.77-,1.4.-,and 1.87-fold,respectively,compared with *** expression of the OPNgene was upregulated(P4.Ca2+uptake and ALP activity in the VDN plus NaHSgroup was lower than that in the VDN *** content of calcium and4.Ca2+accumulation and activity of ALP in the aorta were 3..8%,4..75% and 63.5% lowerin the low-dosage NariS group than in the VDN group,respectively(P4.Ca2+and activity of ALP was 83.9%,3..8 % and 4..2% lower in the aorta in the high-dosage NariS group than in theVDN group,respectively(P<0.01).The expression of the OPN gene ***:The production of H,S,and CSE activity were de-creased and CSE gene expression was downregulated in rats with vascularcalcification.H2S can ameliorate vascular calcification,suggesting that the H2S/CSE pathway plays a regulatory role in the pathogenesis of vascular calcification.

关键词： hydrogen sulfide cystathionine-lyase vascular calcification mRNA

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Comparison of the influence factors on NDVI for CCD camera and WFI imager on CBERS-02

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Science china(Technological Sciences) 2005年第S2期48卷 100-115页

作者： YU Tao1,3. LI Xiaoying1,2,3. ZHANG Yong1,2,3. ZHAO Feng1,2,3. GU Xingfa1,3.4. ZHU Li1,2,3. WANG Pengxin5 & MIN Xiangjun6 1. State Key Laboratory of Remote Sensing Science Institute of Remote Sensing Application, CAS, Bei- jing 100101, china 2. Graduate university of Chinese Academy of Sciences, Beijing 10003., china 3. The {3. for National Spaceborne Demonstration, Beijing 100101, china 4. Institut National de la Recherche Agronomique, Climat Sol Environnement, 84.14.Avignon, France 5. College of information and Electrical Engineering, china Agricultural university, Beijing 100083. china 6. china {3. for Resource Satellite Data and Application, Beijing 10083., china State Key Laboratory of Remote Sensing Science Institute of Remote Sensing Application CAS Beijing 100101 China

CCD and WFI are payloads in the visible light and near infrared bands on CBERS satellites and they have not been applied widely, especially WFI. This article mainly probes into the potential of these two sensors’ application in the vegetation monitoring and analyses the influences of radiometric calibration, atmosphere conditions and sun-observing geometry, etc. on NDVI obtained from these two sensors respectively. In addition it analyses the effect of the spectral response difference of red and near infrared spectral bands in CCD and WFI sensors on NDVI. Results indicate that radiometric calibration is the most important factor on NDVI, which cannot be applied to vegetation monitoring without radiometric calibration. Results also demonstrate that near surface NDVI is different greatly from that of TOA which change with atmosphere conditions. The study shows that NDVI is also affected by the non-lambertian character of surface and the change of the atmospheric path with the observing geometry. And NDVI of WFI is higher than that of CCD. They are very different because of their spectral difference, but they have a good linear relevant relationship.

关键词： CCD WFI NDVI LAI.

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Expression of PDCD5 , a novel apoptosis related protein, in human osteoarthritic cartilage

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Acta Pharmacologica Sinica 2004年第05期25卷 143-148页

作者： Ai-xin CHENG, Si-quan LOU2, Hao-wei ZHOU, Ying WANG3. Da-long MA3.epartment of Orthopaedic Surgery, Third Hospital, peking university, Beijing 100083.3.1} for Human Disease Genomics, peking university, Beijing 100083.{3. Department of Orthopaedic Surgery Third Hospital Peking University center for Human Disease Genomics Peking University

AIM: To investigate the expression features of PDCD5 (programmed cell death 5 protein) in osteoarthritic andnormal human cartilage, and speculate on its potential functions in the pathogenesis of osteoarthritis (OA).METHODS: Articular cartilage specimens were obtained from 3. patients with OA and 16 healthy patients at thetime of arthroplasty. Expression of PDCD5 was detected by flow cytometry, immunofluorescence, RT-PCR andimmunohistochemical analysis. RESULTS: Enhanced expression and nuclear accumulation of PDCD5 in OAchondrocytes were found. PDCD5-positive chondrocytes were mainly distributed in the superficial and deep zonesof OA tissue sections, as opposed to, in the superficial and middle regions of normal healthy tissue ***: Since apoptotic chondrocyte death occurs more frequently in OA cartilage than in normal healthycartilage and PDCD5 is an apoptosis-related protein, the different expression patterns of PDCD5 in OA cartilagefrom that in normal healthy cartilage indicate that PDCD5 is involved in the pathogenesis of OA.

关键词： apoptosis cartilage osteoarthritis PDCD5

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A novel method for evaluating and improving the 1H-MRSI glioma data quality

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Progress in Natural Science:Materials International 2005年第8期15卷 765-768页

作者： YUAN Kehong 1,2, LU Hongyu2, BAO Shanglian2*, CHEN Qiansheng1, LI Shaowu3.and DUAN Chaijie2(1. Key Laboratory of Pure and Applied Mathematics, School of Mathematical Sciences, Beijing 100871, china 2. The Research center for Tumor Diagnosis and Therapeutical Physics & the Beijing Key Laboratory of Medical Physics and Engineering,{3., Beijing 100871, china 3. The Tian Tan Hospital, Beijing 100050, china) Key Laboratory of Pure and Applied Mathematics School of Mathematical Sciences Beijing 100871 China. The Research center for Tumor Diagnosis and Therapeutical Physics & the Beijing Key Laboratory of Medical Physics and Engineering Peking University Beijing 100871 China. The Tian Tan Hospital Beijing 100050 China

Metabolic information obtained by proton magnetic resonance spectroscopic imaging (1H-MRSI) has been approved to be a powerful tool to identify either benign or malignant glioma, as well as to confirm the tumor level. However, 1H-MRSI data are affected by various factors, such as the thermal noise, eddy currents, susceptibility artifacts, and rigid body motion. To get accurate quantitative metabolic information, the key problem is to assess the 1H-MRSI data quality. In this paper, we introduce a new evaluating system to filter the data, and a new method, called wavelet denoising method, to improve the data quality under the evaluating system. Experimental results on 1H-MRSI glioma data demonstrate that preprocessing is prerequisite and the proposed algorithm with evaluating system is effective.

关键词： 1H-MRSI evaluating system glioma data quality wavelet denoising

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Numerical study of the auroral particle transport in the polar upper atmosphere

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Science china(Technological Sciences) 2008年第10期51卷 1759-1771页

作者： CAI HongTao1,2, MA ShuYing1,2 & PU ZuYin3.1 School of Electronic information, Wuhan university, Wuhan 4.0}079,{4. 2 Key Laboratory of Geospace Environment and Geodesy, Ministry of Education of PRC, Wuhan 4.0}079,{4. 3.School of Earth and Space Sciences, peking university, Beijing 100871,{4. School of Electronic information Wuhan University Key Laboratory of Geospace Environment and Geodesy Ministry of Education of PRC School of Earth and Space Sciences Peking University

Starting from the Boltzmann equation and with some reasonable assumptions, a one-dimensional transport equation of charged energetic particles is derived by taking account of major interactions with neutral species in the upper atmosphere, including the processes of elastic scattering, the excitation, the ionization and the secondary electron production. The transport equation is numerically solved, for a simplified atmosphere consisting only of nitrogen molecules (N2), to obtain the variations of incident electron fluxes as a function of altitude, energy and pitch angle. The model results can describe fairly the transport characteristics of pre-cipitating auroral electron spectra in the polar upper atmosphere; meanwhile the N2 ionization rates calculated from the modeled differential flux spectra also exhibit good agreements with existing empirical models in terms of several key parameters. Taking the energy flux spectra of precipitating electrons observed by FAST satellite flying over EISCAT site on May 15, 1997 as model inputs, the model-calculated ionization rate profile of neutral atmosphere consists reasonably with that recon-structed from electron density measurements by the radar.

关键词： aurora particle precipitation polar upper atmosphere electron transport equation numerical simulation

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Constraints on smoothness parameter and dark energy using observational H(z) data

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Research in Astronomy and Astrophysics 2011年第2期11卷 125-136页

作者： Hao-Ran Yu1,Tian Lan1,Hao-Yi Wan2,Tong-Jie Zhang1,3.and Bao-Quan Wang4.1 Department of Astronomy,Beijing Normal university,Beijing 100875,china 2 Business Office,Beijing Planetarium,Beijing 10004.,china 3.{3. for High Energy Physics,peking university,Beijing 100871,china 4.Department of Physics,Dezhou university,Dezhou 253.23.china Department of Astronomy Beijing Normal University Business Office Beijing Planetarium

With large-scale homogeneity,the universe is locally inhomogeneous,clustering into stars,galaxies and larger *** property is described by the smoothness parameter α which is defined as the proportion of matter in the form of intergalactic *** we consider the inhomogeneities over a small scale,there should be modifications of the cosmological distances compared to a homogenous *** and Roeder developed a second-order ordinary differential equation（D-R equation） that describes the angular diameter distance-redshift relation for inhomogeneous cosmological ***,we may obtain the D-R equation for observational H（z） data（OHD）.The density-parameter ΩM,the state of dark energy ω,and the smoothness-parameter α are constrained by a set of OHD in a spatially flat XCDM universe as well as a spatially flat XCDM *** using a χ2 minimization method,we get α = 0.81＋0.19-0.20 and ΩM = 0.3.＋0.12-0.06 at the 1σ confidence *** we assume a Gaussian prior of ΩM = 0.26 ± 0.1,we get α = 0.93.0.07-0.19 and ΩM = 0.3.＋*** the XCDM model,α is constrained to α≥ 0.80 but ω is weakly constrained around-1,where ω describes the equation of state of the dark energy（pX = ωρX）.We conclude that OHD constrains the smoothness parameter more effectively than the data of SNe Ia and compact radio sources.

关键词： cosmology -- dark energy -- cosmological parameters

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A new Early Cretaceous lizard with well-preserved scale impressions from western Liaoning, china

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Progress in Natural Science:Materials International 2005年第2期15卷 67-73页

作者： JI Shu’an*(School of Earth and Space Sciences, peking university, Beijing 100871, china) School of Earth and Space Sciences Peking University Beijing 100871 China

A new small lizard, Liaoningolacerta brevirostra gen. et sp. nov., from the Early Cretaceous Yixian Formation of western Liaoning is described in detail. The new specimen was preserved not only by the skeleton, but also by the exceptionally clear scale impressions. This lizard can be included within the taxon Scleroglossa based on its 26 or more presacrals, cruciform interclavicle with a large anterior process, moderately elongated pubis, and slightly notched distal end of tibia. The scales vary evidently in size and shape at different parts of body: small and rhomboid ventral scales, tiny and round limb scales, and large and longitudinally rectangular caudal scales that constitute the caudal whorls. This new finding provides us with more information on the lepidosis of the Mesozoic lizards.

关键词： new genus Squamata skeleton lepidosis Early Cretaceous western Liaoning

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