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Chinese Chemical Letters 1997年第11期8卷 935-936页

作者： Wen PEI(department of Chemistry, Yanbian university, Yanji, 133002)Eiji WADA and Shuji KANEMASA (Institute of Advanced Material study, Kyushu university, Kasugakoen, Kasuga 816, japan) department of Chemistry Yanbian University Yanji 133002 China Institute of Advanced Material Study Kyushu University Kasugakoea Kasuga 816 Japan

Double asymmetric Diels-Alder reaction of 1(SR)-p-Tolylsulfinyl-3-penten-2-one with cyclopentadiene using a chiral titanium reagent was performed. The diastereoselectivity dependent on the size of aryl substituent involved in the chiral ligands was discussed Absolute configuration of the cycloadducts was conformed. Dramatic reversal of selectivity is observed.

关键词： p-Tolylsulfinyl-3-penten-2-one with Cyclopentadiene Catalzed by a Chiral Titanium Reagent S_R Asymmetric Diels-Alder Reaction of 1

Occupation Measures of Singularly Perturbed Markov Chains with Absorbing States

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Acta Mathematica Sinica,English Series 2000年第1期16卷 161-180页

作者： G.Yin~(1)) department of Mathematics,Wayne State university,Detroit,MI 48202,USAQ.Zhang~(2)) department of Mathematics,university of Georgia,Athens,GA 30602,USAG.Badowski~(3)) department of Mathematics,Wayne State university,Detroit,MI 48202,USA department of Mathematics Wayne State University Detroit MI 48202 USA department of Mathematics University of Georgia Athens GA 30602 USA

This paper develops asymptotic properties of singularly perturbed Markov chains with inclusion of absorbing *** focuses on both unscaled and scaled occupation *** mild conditions,a mean-square estimate is *** averaging the fast components,we obtain an aggregated *** the aggregated process itself may be non-Markovian,its weak limit is a Markov chain with much smaller state ***,a suitably scaled sequence consisting of a component of scaled occupation measures and a component of the aggregated process is shown to converge to a pair of processes with a switching diffusion component.

关键词： Singularly perturbed Markov chain Occupation measure Aggregation Absorbing state Weak convergence Switching diffusion

Time lag between reduction of sediment supply and coastal erosion

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International Journal of Sediment Research 2011年第1期26卷 27-35页

作者： HUANG Guangwei~1 university of Tokyo,japan, [a] Dr. university of Tokyo japan

The disruption of sediment supply from river to coast by dam development has been a topic of global *** japan,among the top 30 dams in terms of height,14 dams were constructed prior to 1970 and another 6 dams before ***,the coastline erosion did not surface up as a grievous problem until the *** to the River Bureau of japan,the overall erosion rate along the coastline of japan was 0.72×10~6 m~2/yr prior to 1980,but sharply increased to 1.6×10~6 m~2/yr since ***,there was a time lag between the disruption of sediment supply by dam and beach *** paper presents a case study on what may have delayed the response of beach to the effect of dam construction.

关键词： Erosion Sediment supply Dam Sand mining Time lag

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 MA3department of Orthopaedic Surgery, Third Hospital, Peking university, Beijing 100083 3Center for Human Disease Genomics, Peking university, Beijing 100083, China 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 30 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

Theoretical study on the reaction mechanism of(CH_3)_3CO+CO

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Science China Chemistry 2005年第1期48卷 18-24页

作者： ZHAO Hongmei1,2,3, SUN Chengke1,4, ZHANG Rongchang3, XI Hongmin3 & LI Zonghe1 1. department of Chemistry, Beijing Normal university, Beijing 100875, China 2. The Laboratory of Molecular Reaction Dynamics, Institute of Chemistry, Chinese Academy of Sciences, Beijing 100080, China 3. department of Chemistry, Beihua university, Jilin 132013, China 4. department of Chemistry, Qujing Normal university, Yunnan 655000, China 1. department of Chemistry Beijing Normal University 100875 Beijing China 2. The Laboratory of Molecular Reaction Dynamics Institute of Chemistry Chinese Academy of Sciences 100080 Beijing China 3. department of Chemistry Beihua University 132013 Jilin China 4. department of Chemistry Qujing Normal University 655000 Yunnan China

The reaction mechanism of (CH3)3CO with CO has been theoretically investigated using density-functional theory (DFT) calculations at B3LYP/6-31G* level. In order to get more reliable energy values the single-point energy is evaluated at CCSD (T)/6-31++G** level. The results show that the reaction is multi-channel and the reaction of (CH3)3CO radical with CO mostly produces (CH3)3C + CO2. The reaction could play a role in eliminating air pollution.

关键词： DFT, B3LYP, (CH3)3CO, radical.

Prevention of pathological change and cognitive degeneration of Tg2576 mice by inoculating Aβ_(1-15) vaccine

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Science China(Life Sciences) 2008年第8期51卷 743-750页

作者： HU JinJia1, LI GuoYing2, WANG HuaQiao3, LIN Xian3 & YAO ZhiBin3 1 department of Anatomy, Medical College of Shanghai Jiao Tong university, Shanghai 200025, China 2 department of Anatomy, Preclinical College, Guangdong university of Pharmacy, Guangzhou 510006, China 3 department of Anatomy, Zhongshan School of Medicine, Sun Yat-sen university, Guangzhou 510080, China 1. department of Anatomy Medical College of Shanghai Jiao Tong University Shanghai 200025 China 2. department of Anatomy Preclinical College Guangdong University of Pharmacy Guangzhou 510006 China 3. department of Anatomy Zhongshan School of Medicine Sun Yat-sen University Guangzhou 510080 China

This study aims to discuss the effect of preventing pathological changes and cognitive degeneration of Tg2576 mice by inoculating the subunit fragment of Aβ ***-two Tg2576 mice were randomly divided into four groups, each having eight mice:Group I, the control group, inoculated with adjuvants;Group II, the Aβ42 group, inoculated with Aβ42 vaccine;Group Ⅲ, the Aβ1―15 group, inoculated with Aβ1―15 vaccine;and Group IV, the Aβ36―42 group, inoculated with Aβ36―42 *** titer of the serum anti-body against Aβ42(Group II) was significantly higher than that of the control group(Group I), and a low level of antibodies could be detected in the brain homogenate in the three vaccine-inoculated *** water maze test showed that the Aβ42 group, Aβ1―15 group and Aβ36―42 group were obviously im-proved compared with the control *** cultured splenocytes sampled from each group were induced by Con A or their respective antigens, and the cell proliferation of the three vaccine-inoculated groups was significantly higher than that of the control *** the Aβ42 group, IL2 and IFN-γ were relatively low and IL4 and IL10 were relatively *** contrast, IL4 and IL10 were much higher in the Aβ1―15 group and IL2 and IFN-γ were much higher in the Aβ36―42 *** immunohistochemical test showed a large number of senile plaques in the brain cortex and hippocampus of the mice in the con-trol group, no senile plaque in the brain of the Aβ1―15 group and Aβ42 group mice, and a small number of senile plaques in the brain of the Aβ36―42 group *** results suggest that the subunit fragment of Aβ1―15 vaccine could prevent not only cognitive and behavioral degeneration but also Aβ deposition and formation of senile plaques in Tg2576 mice.

关键词： Alzheimer’s disease β-amyloid peptide vaccine Tg2576 mice senile plaque

A SINGLE-PERIOD INVENTORY SYSTEM WITH A GENERAL S-SHAPED UTILITY AND EXPONENTIAL DEMAND

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Journal of Systems Science and Systems Engineering 2010年第2期19卷 227-236页

作者： Wei GENG1 Xiaobo ZHAO2 Deng GAO3 department of Industrial Engineering,Tsinghua university,Beijing 100084,China department of Industrial Engineering Tsinghua University Beijing China

We discuss a single-period inventory system with a general S-shaped utility function and exponential demand. It is shown that there exists a state-dependent order-up-to policy to be optimal. Behaviors of optimal polic... 详细信息

关键词： Inventory S-shaped utility function order-up-to policy

Mass spectrometric identification of double bond positional isomers of hexadecenyl acetate without chemical derivatization

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Chinese Journal of Chemistry 1994年第4期12卷 348-354页

作者： YUAN, Gudepartment of Chemistry, Peking university, Beijing 100871, ChinaHORIIKE, Michio KIM, Chul-Sa HIRANO, Chisato department of Agricultural Chemistry, Kochi university, Nankoku-shi, Kochi 783, japan 1department of Chemistry Peking University Beijing 100871 China2Department of Agricultural Chemistry Kochi University Nankoku-shi Kochi 783 Japan

A method for the identification of the double bond positional isomers of hexadecenyl acetate has been established by analysing similarity of the mass spectra patterns on a fuzzy classification, in which the intensity ratios of six diagnostic pairs of the predominant ions were selected as standard parameters for the characterization of the double bond position. The procedure was tested with △2 to △15-isomers of chemically unmodified hexadecenyl acetate, and the original double bond position in the acetates was located unambiguously.

关键词： Mass spectrometer double bond positional isomers hexadecenyl acetates.

Fluid Flow Behavior of Liquid in Cylindrical Vessels Stirred by One or Two Air Jets

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International Journal of Minerals,Metallurgy and Materials 2000年第3期14卷 170-177页

作者： Lifeng Zhang, Shoji Taniguchi, Kaike Cai, Ying Qu ( department of Metallurgy Graduate School of Engineering, Tohoku university, Sendai 980-579 japan Metallurgy School, university of Science and Technology Beijing, Beijing 100083, China) department of Metallurgy Graduate School of Engineering Tohoku University Sendai 980-8579 Japan Metallurgy School University of Science and Technology Beijing Beijing 100083 China

Based on the two-phase model (Eulerian-Eulerian model), the three dimensional fluid flow in water and that liquid steel systems stirred by one or two multiple gas jets are simulated. In the Eulerian-Eulerian two-phase model, the gas and the liquid phase are considered to be two different continuous fluids interacting with each other through the finite inter-phase areas. The exchange between the phases is represented by source terms in conversation equations. Turbulence is assumed to be a property of the liquid phase. A new turbulence modification - model is introduced to consider the bubbles movement contribution to and . The dispersion of phases due to turbulence is represented by introducing a diffusion term in mass conservation equation. The mathematical simulation agrees well with the experiment results. The study results indicate that the distance of two nozzles has big effect on fluid flow behavior in the vessel. Using two gas injection nozzles at the half radii of one diameter of the bottom generates a much better mixing than with one nozzle under the condition of the same total gas flow rate.

关键词： fluid flow two-phase Eulerian-Eulerian model model mathematical simulation

Construction of tissue-engineered cartilage using human placenta-derived stem cells

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Science China(Life Sciences) 2010年第2期53卷 207-214页

作者： LIU DaShun1,2,HUI HuangFu3,CHAI XiangBin3,WANG BinQuan3 & QIU JianHua1 1 department of ENT,Xijing Hospital,the Foruth Military Medical university of PLA,Xi’an 710032,China 2 department of ENT,264 Hospital of PLA,Taiyuan 030001,China 3 department of ENT,the First Hospital of Shanxi Medical university,Taiyuan 030001,China 1. department of ENT Xijing Hospital the Foruth Military Medical University of PLA Xi’an 710032 China2. Department of ENT 264 Hospital of PLA Taiyuan 030001 China3. Department of ENT the First Hospital of Shanxi Medical University Taiyuan 030001 China

Human placenta-derived stem cells (hPDSCs) were isolated by trypsinization and further induced into cartilage cells in *** engineered cartilage was constructed by combining hPDSCs with collagen sponge and the cartilage formation was observed by implantation into nude *** showed that hPDSCs featured mesenchymal stem cells and maintained proliferation in vitro for over 30 passages while remaining *** results indicated that hPDSCs have the potential to differentiate into functional cartilage cells in vitro when combined with collagen sponge,which provided experimental evidence for prospective clinical application.

关键词： human placenta-derived stem cells collagen sponge cartilage tissue engineering