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Metamorphism of the Bikou Group in the shanxi-Gausu-sichuan Border Region

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Acta Geologica sinica(English Edition) 1995年第1期69卷 53-68页

作者： Wei ChunjingDepartment of Geology, Peking u niversity, beijing Fei Zhenbi Department of Geology Peking University Beijing

The Blkou Group on the shaanxi-Gansu-sichuan border is composed of Mid-Late Proterozoic metamorphosed bimodal.volcanic rocks and flysch sediments. Its metamorphism may be divided into the blueschist and greenschist facies. Three metamorphlc zones, i.e. zones A, B, and C, may be distinguished on the basis of the field distribution of metamorphlc rocks and the variation of b0 val.es of muscovite. Blueschists are characterized by coexistence of sodic amphiboles and epidote and occur as stripes or relict patches in extensive greenschists of zone A. studies of metamorphic mineral. such as amphiboles, chlorite, epidote and muscovite and their textural.relationships indicate that blueschists and greenschists were not formed under the same metamorphic physico-chemical.conditions. The blueschist facies was formed at temperatures of 300-400℃ and pressures of 0.5-0.6 GPa. The greenschist facies in zones A and B has similar temperatures but its pressure is only 0.4 GPa or so. The transition from the blueschist to greenschist facies is a nearly isothermal.uplift process. The rock and mineral.assemblages of the Bikou Group indicate that the blueschist facies metamorphism of the group might be related to crustal.thickening or A-subduction accompanying the closure of an intracontinental.smal. ocean basin.

关键词： metamorphic mineral blueschist greenschist metamorphism Bikou Group

The Best Natural.Boundary:a New Concept Developed by Combining the sequence Boundary with the GssP

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Acta Geologica sinica(English Edition) 1996年第1期70卷 98-106页

作者： Mei shilong China u niversity of Geosciences, beijing China u niversity o fGeosciences Beijing

Through a detailed study of sequence boundaries, it is concluded that sequence stratigraphy is an independent regional.and transitional.stratigraphic system between local.lithostratigraphy and global.chronostratigraphy. Therefore, a new tripartite stratigraphic classification scheme has been proposed. By combining organical.y the concept of sequence boundaries with the GssP, it is suggested that the GssP should be chosen in a conformal. portion of a related sequence boundary, and the boundary established in light of this concept is defined as the Best Natural.Boundary (BNB). The definition of the BNB points out the working area and stratigraphic level for the GssP. By referring to a case study of the Permian Guadal.pian/Lopingian boundary, the concept of the BNB has been elaborated in detail, and it is proposed that the BNB of the Guadal.pian and the Lopingian lies between the Mesogondolella granti Zone and the Ctarkina postbitteri Zone, which is al.o the sequence chronostratigraphic boundary between the Transpecos composite sequence (chronozone)and the uAA- 1 composite sequence (chronozone).

关键词： sequence boundary new tripartite stratigraphic classification scheme GssP best natural.boundary Guadal.pian/Lopingian boundary

Changes of CD8+CD28-T regulatory cells in rat model of colitis induced by 2,4-dinitrofluorobenzene

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World Journal.of Gastroenterology 2003年第11期9卷 2528-2532页

作者： Wen-Bin Xiao, Department of Gastroenterology, Peking university people’s hospital, beijing 100044, China Yu-Lan Liu, Department of Gastroenterology, Peking university people’s hospital, beijing 100044, China Department of Gastroenterology Peking University People's Hospital Beijing 100044 China.

AIM:To determine the changes of CD8+ T subsets especial.y CD8+CD28-T regulatory cells in rat model of experimental.colitis induced by 2,4-dinitrofluorobenzene (DNFB). MetHODs:The rat model of experimental.colitis was induced by enema with *** days later,colonic intraepithelial.and splenic lymphooltes were isolated from colitis animal. (n=16) and controls (n=8).The proportion of CD8+ T cells,CD8+CD28+ T cells and CD8+CD28-T regulatory cells were determined by flow cytometry. REsuLTs:The model of experimental.colitis was successfully established by DNFB that was demonstrated by bloody diarrhea,weight loss and colonic *** proportion of CD8+ T cells in either splenic or colonic intraepithelial.lymphocytes was not significantly different between colitis animal. and controls (spleen:34.6±7.24 % vs 33.5±9.41%, colon:14.0±8.93 % vs 18.0±4.06 %,P>0.05).But CD8+CD28- T regulatory cells from colitis animal. were significantly more than those from controls (spleen:11.3±2.26 % vs 5.64±1.01%, colon:6.50±5.37 % vs 1.07±0.65 %,Pst, CD8+CD28+ T cells from colitis animal. were less than those from controls (spleen:23.3±6.14 % vs 27.8±9.70 %,P=0.06; colon:7.52±4.18 % vs 16.9±4.07 %,Pulatory cells in splenic and colon intraepithelial.CD8+ T cells from colitis animal. was higher than that from controls (spleen:33.3±5.49 % vs 18.4±7.26 %, colon:46.0±14.3 % vs6.10±3.72 %,PusION:Experimental.colitis of rats can be induced by DNFB with simplicity and good *** proportion of CD8+CD28-T regulatory cells in rats with experimental.colitis is increased,which may be associated with the pathogenesis of colitis.

关键词： Animal. Antigens, CD28 CD8-Positive T-Lymphocytes Colitis Colon Dinitrofluorobenzene Disease Models, Animal Flow Cytometry Mal. Rats Rats, sprague-Dawley Research support, Non-u.s. Gov't specific Pathogen-Free Organisms spleen

The Existence of the Negative Charge of Gold in sulphide Mineral. and Its Formation Mechanism

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Acta Geologica sinica(English Edition) 1995年第3期69卷 303-315,341页

作者： Li Jiuling, Feng Daming, Qi Feng and Zhang Guilan Institute of Mineral.Deposits, Chinese Academy of Geological.sciences, beijing beijing u niversity of science and Engineering, beijing Fei Zhenbi 1 Institute of Mineral.Deposits Chinese Academy of Geological Sciences Beijing2 Beijing University of Science and Engineering Beijing

Through a study, particularly an X-ray photoelectron spectroscopy (XPs or EsCA) anal.sis, of gold-bearing arsenopyrite and pyrite in Carlin-type gold deposits of Guangxi, China, and hydrothermal.y synthesized gold-bearing pyrite and marcasite, the authors have found that these mineral. contain 'invisible gold' whose binding energy is lower than that of native gold (Au°). Therefore they suggest that gold occurs in a negative charge state in these sulphide mineral. as it replaces some sulphur and is combined with sulphur with the coval.nt bond. This paper al.o preliminarily discusses the possibility of its formation from the chemistry and geochemistry of gold, crystal.chemistry of arsenopyrite, pyrite and marcasite and geochemical.environment.

关键词： Carlin-type gold deposit sulphide invisible gold chemical.bound gold negative charge of gold

TAXONOMIC sTuDIEs ON THE sCIARIDAE (PIPTERA: NEMATOCERA)OF GuIZHOu

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Entomotaxonomia 1993年第4期 312-318页

作者： YANG Chi-kun, ZHANG Xuemin and YANG ChunqingDepartment of Plant Protection, beijing Agricultural.u niversity, beijing 100094Chinese Academy of Agricultural.sciences, beijing 100094Chinese Academy of medical sciences, beijing 100094

The family sciaridae of Guizhou Province contains 10 genera and 57 species, ofwhich 1 genus and 43 species are new to science. The new taxa are described in taxonomickeys. The type specimens are kept in the Insect Collection of beijing Agricultural.univer-sity. The letters given here are local.ty abbreviations used in the genus and specics listthat follows.

关键词： Diptera sciaridae New species Guizhou.

The Existence of BIB Designs

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Acta Mathematica sinica,English series 2000年第1期16卷 103-112页

作者： Yanxun Chang Institute of Mathematics,Northern Jiaotong university,beijing 100044,P.R.China Institute of Mathematics Northern Jiaotong University Beijing 100044 P.R. China

Given any positive integers k3 and λ,let c（k,λ）denote the smal.est integer such that u ∈ B（k,λ）for every integer uc（k,λ）that satisfies the congruences λv（v-1）≡0（mod k（k-1））and λ（u-1）≡0（mod k-1）.In this article we make an improvement on the bound of c（k,λ）provided by Chang in[4]and prove that c（k,λ）exp{ksup>3ksup>6sup>sup>}.In particular,c（k,1）exp{ksup>ksup>2sup>sup>}.

关键词： Wilson’s theorem Bal.nced incomplete block design PBD-closed

Function of chymase in the heart angiotensin Ⅱ formation in transgenic mice

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Chinese science Bulletin 2001年第11期46卷 922-925页

作者： LI Peng & CHEN LanyingCardiovascular Institute & Fu Wai hospital, Chinese Academy of medical sciences & Peking union medical College, beijing 100037, China Cardiovascular Institute & Fu Wai hospital Chinese Academy of Medical Sciences & Peking Union Medical College Beijing China

The myosin light chain 2 promoter-human heart chymase (MLC2-hChymase) transgenic mice founded by our laboratory were used as the model to study the function of chymase in the heart angiotension Ⅱ (Ang Ⅱ) formation and heart remodeling. Tissue-specific expression of human heart chymase gene and transcriptional.expression of type Ⅰ and type Ⅲ collagens genes were anal.zed by RT-PCR. Activities of chymase, ACE and the levels of Ang Ⅱ in heart and plasma were determined with radioimmunoas-say (RIA) kit. Activity of heart matrix metal.oproteinase-9 (MMP-9) was detected using gelatin zymography. The cardiac hypertrophic phenotypes were al.o observed with the physiological.and morphological.methods. The results in the MLC2-hChymase transgenic mice indicated: ( i ) human heart chymase gene was expressed special.y in the heart; (u) heart chymase activity increased markedly in the transgenic mice vs non-transgenic mice (control) (0.27±0.07 u/mg vs. 0.15±0.02 u/mg, Psignificant difference in

关键词： chymase transgenic mice angiotensin Ⅱ heart remod- eling collagen.

some Performances Eval.ation for Cellular Ds-sFH systems

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电波科学学报 1998年第3期13卷 275-279页

作者： Zhang Xiaowen Ni Jianjun Yang Lieliang and Li Chengshu (Modern Comunications Institute, Northem Jiaotong u., beijing 100044)

The performance of a cellular radio direct-sequence slow frequency hopping code-division multiple-access system is examined. The forward and reverse links that are modeled as tlat Rayleigh fading channels are discussed. In base-to-mobile transmission modc, al. signal. transmitted from a given basc station suffer fading in unison: but in mibile-to-base' the waveforms from different users undergo independent fading Three cells and seven cells are considered in the forward and reverse ***. We assume that al. users employ noncoherent DPsK modulation and the waveforms are transmitted asynchronously, and inde-pendent first-order Markov random hopping pattern is used In addition, the forward error-correcting coding is used for crror-correction

关键词： Direct-sequence spread-spectrum slow frequency hopping code division multiple access (CDMA) cellularr system error-control

sIMuLATING REGIONal.sYsTEMs: A sYsTEM DYNAMICs APPROACH

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Journal.of Geographical.sciences 1996年第2期6卷 1-14页

作者： Colllin Lee(school of the Built Environment, Coventry university, Coventry, u.K.)Guo Rongxing (beijing Graduate school of CuMT, and Paking university, beijing 100871 people’s Republic of China )

system dynamics is a rigorous method for qual.tative description,exploration and anal.sis of complex systems in terms of their processes, information flows, orgaruzational.boundaries and strategies, which facilitates quantitative modelling and anal.sis for design of system structure and the improvement of system behaviour. It can be applied to the study of a wide range of systems, and its ability to describe socio-economic characteristics and behaviour makes it suitable for the anal.sis of the regional.development process. Three examples of system Dynamics models are reviewd to demonstrate the suitability of the method for regional.anal.sis, and on the basis of this review the potential.use of system dynamics models in China is discussed.

关键词： system dynamics model simulation sustainable development