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PrP mutants with different numbers of octarepeat sequences are more susceptible to the oxidative stress

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Science china(Life Sciences) 2008年第7期51卷 630-639页

作者： AN Run1 ,2.DONG ChenFang 2.LEI YanJun 1,2.HAN Lu 2.LI Ping 2.CHEN JianMing 2.WANG GuiRong 2. SHI Qi 2.,GAO Chen 2.,JIANG HuiYing 2.,ZHOU Wei 2.,HAN Jun 2.,CHU YongLie 1 ,DONG XiaoPing 2.1School of Medicine,Xi’an JiaoTong {13.,Xi’an 710061,china 2.tate Key Laboratory for Infectious Disease Prevention and Control,National Institute for Viral Disease Control and Prevention, Chinese Center for Disease Control and Prevention,YingXin Rd 100,{2. 100052.china 1. School of Medicine Xi’an JiaoTong University Xi’an 710061 China 2. State Key Laboratory for Infectious Disease Prevention and Control National Institute for Viral Disease Control and Prevention Chinese Center for Disease Control and Prevention YingXin Rd 100 Beijing 100052 China

One of the physiological functions of cellular prion protein(PrP C )is believed to work as a cellular resistance to oxidative stress,in which the octarepeats region within PrP plays an important ***,the detailed mechanism is less *** this study,the expressing plasmids of wild-type PrP (PrP-PG5)and various PrP mutants containing 0(PrP-PG0),9(PrP-PG9)and 12.PrP-PG12.octarepeats were generated and PrP proteins were expressed both in *** and in mammalian *** aggregation and formation of carbonyl groups were clearly seen in the recombinant PrPs expressed from *** after treatment of *** and trypan blue staining assays revealed that the cells expressing the mutated PrPs within octarepeats are less viable than the cells expressing wild-type *** significant high levels of intracellular free radicals and low levels of glutathione peroxidase were observed in the cells transfected with plasmids containing deleted or inserted *** more productions of carbonyl groups were detected in the cells expressing PrPs with deleted and inserted octarepeats after exposing to ***,cells expressing wild-type PrP showed stronger resistant activity to the challenge of H2.2.at certain extent than the mutated PrPs and mock. These data provided the evidences that the octarepeats number within PrP is critical for maintaining its activity of *** of its protective function against oxidative stress may be one of the possible pathways for the mutated PrPs to involve in the pathogenesis of familial Creutzfeldt-Jacob diseases.

关键词： prion protein oxidative stress glutathione peroxidase reactive oxygen species cell viability

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高速机车主动控制受电弓研究

铁道学报 2004年第4期26卷 41-45页

作者：郭京波杨绍普高国生北京交通大学机电工程学院北京100044 石家庄铁道学院机械工程分院河北石家庄050043

受电弓与接触网之间的振动问题,一直是制约电力机车提速的关键之一。本文对2.类型接触网的刚度进行了非线性最小二乘曲线拟合,并给出了统一的拟合公式,建立了3.由度弓网系统模型,采用最优控制策略,对不同运行速度下弓网间接触力进行... 详细信息

受电弓与接触网之间的振动问题,一直是制约电力机车提速的关键之一。本文对2.类型接触网的刚度进行了非线性最小二乘曲线拟合,并给出了统一的拟合公式,建立了3.由度弓网系统模型,采用最优控制策略,对不同运行速度下弓网间接触力进行主动控制。仿真结果表明,采用主动控制受电弓可以有效地抑制接触力的波动,控制效果较好。

关键词：受电弓接触网高速列车主动控制

A Research about A MIMO System Identification Algorithm Based on ANN Using Slide Mode Variable Structure

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A Research about A MIMO System Identification Algorithm Base...

2.11 Chinese Control and Decision Conference（CCDC）

作者： Yahui Wang1,Peixin Cheng 2.Zhifeng Xia3.1.Department of Automation Engineering,beijing university of Civil & Architecture Engineering,beijing 100044,china2.china Architecture Design&Research Group,beijing 100044,china3.beijing Forestry university,beijing 100083.china

Applying sliding mode variable structure control to train neural networks is proposed in this paper,which can not only increases learning rate but also improves the stability of ***,this method helps to promote the generalization capacity of *** order to improve the generalization ability,two sliding mode objective functions are designed based on previous researches for a new neural-network learning *** analysis shows that the proposed algorithm increases the generalization ability and robustness of neural-network,meanwhile,enhances the identification accuracy.

关键词： MIMO System Identification Sliding Mode Variable Structure Neural-Network Generalization Ability

Kinematic characteristics and the influence of reference velocities of phase-shift-plus-interpolation and extended-split-step-Fourier migration methods

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Kinematic characteristics and the influence of reference vel...

中国科学院地质与地球物理研究所第十届(2.10年度)学术年会

作者： Jing-Bo Chen~(1*) and Shu-Yuan Du~(1,2. 1 Key Laboratory of Petroleum Geophysics,Institute of Geology and Geophysics,Chinese Academy of Sciences,PO Box 982., beijing 10002.,china,and 2.{2. university of Chinese Academy of Sciences,beijing 100049,china

The phase-shift-plus-interpolation and extended-split-step-Fourier methods are wavefield-continuation algorithms for seismic migration *** two methods can be applied to regions with complex geological *** on their unified separable formulas,we show that these two methods have the same kinematic characteristics by using the theory of pseudodifferential *** tests on a Marmousi model demonstrate this *** important aspect of these two methods is the selection of reference velocities and we explore the influence of the selection of reference velocities by comparing the geometric progression method and the statistical *** show that the geometric progression method is simple but does not take into account the velocity distribution while the statistical approach is relatively complex but reflects the velocity distribution.

关键词：

ADAPTIVE SIMULATION OPTIMIZATION STUDY ON FMS DESIGN

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Chinese Journal of Aeronautics 1993年第2期 137-145页

作者： Shen Li-guo (Precision Instruments Department, Tsinghua university,beijing,{2.,100084) Li Zhe-hao (Manuf acturing Engineering Department, beijing university of Aeronautics and Astronautics,beijing,{2.,100083.

FMS-ASS places one simulator within a feedback loop with another computerprogram which plays the role of an automated and "computerized FMS designer". Thisprogram calls on the simulation in an iterative manner, with new parameters on eachiteration, and is referred to here as "Simulation Optimization System (SOS)". This paperattempts to explore adaptive simulation as well as its likely future direction under integrated,intelligent simulation environment and examine the potential of these evolvingfields.

关键词： FMS ADAPTIVE SIMULATION OPTIMIZATION STUDY ON FMS DESIGN

Carbon emission permit allocation and trading

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Journal of Environmental Sciences 1999年第4期11卷 468-473页

作者： CHEN Wen\|ying, WU Zong\|xin (Institute of Nuclear Energy Technology, Tsinghua university, beijing 100084,{2.) 清华大学核能技术设计研究院北京

Nowadays our earth is faced with grim challenge of global climate change. All countries should go into action jointly to mitigate climate change. Carbon emission permit allocation and trading are two important issues to realize global cooperation. In this paper two kinds of comprehensive carbon emission permit allocation methods not only considering equity but also efficiency were advanced. After the carbon permit price was determined, the trading situations in various regions or countries in the world and the global benefits gained from emission trading were expounded. Moreover, the impact of carbon emission permit trading on chinas economy was analyzed.

关键词： climate change carbon permit allocation carbon permit trading comprehensive allocation method

Evidence for existence of a close association between CD14 and CXCR4 on monocytic cell line U93.

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Progress in Natural Science:Materials International 2007年第8期17卷 979-982页

作者： Yang Hengwen Lan Canhui Chen Yinghua~(**) (Laboratory of Immunology,Department of Biology,Tsinghua university Protein Science Laboratory of MOE,beijing 100084,{2.) [a]Laboratory of Immunology Department of Biology Tsinghua University Protein Science Laboratory of MOE Beijing China

The surface expression of HIV-1 coreceptors (CXCR4 and CCR5) on monocytes can be regulated by the ligand of CD14,and the susceptibility of the cells to HIV-1 is then *** previous study found that monoclonal antibody against CD14 could dramatically inhibit CXCR4-mediated chemotaxis and cell-cell *** on these studies,we explored potential relationship between CD14 and CXCR4 on monocytic cell line *** cytometry analysis showed that anti-CXCR4 monoclonal antibody (mAb) 12.5 strongly inhibited binding of the FITC-conjugated anti-CD14 monoclonal antibodies (TUK4 and UCHM1) to U93.,while another CX- CR4-specific mAb B-R2. did not show any effect on this *** the other hand,two anti-CD14 monoclonal antibodies (TUK4 and UCH-M1) obviously inhibited the binding of the PE-conjugated anti-CXCR4 mAb 12.5 to U93. but did not inhibit the binding of mAb 12.5 to CXCR4-transfected 3.3.cells (***4),which indicates that the blocking of mAb 12.5 binding to CXCR4 by CD14- specific mAbs is not involved in the possibility that CD14-specific mAbs directly bind to *** results suggested existence of a close association between CD14 and CXCR4 on monocytic cell line U93..

关键词： CD14 CXCR4 cross-inhibition

A comparative study of the bottomside profile parameters over Wuhan with IRI-2.01 for 1999-2.04

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A comparative study of the bottomside profile parameters ove...

中国科学院地质与地球物理研究所2.06学术年会

作者： Huajiao Chen~(1,2.3.,Libo Liu~1,Weixing Wan~1,and Baiqi Ning~1 1 Institute of Geology and Geophysics,Chinese Academy of Sciences,beijing 10002.,{3. 2.Wuhan Institute of Physics and Mathematics,Chinese Academy of Sciences,Wuhan,{3. 3.graduate School of Chinese Academy of Sciences,beijing 100049,{3.

The diurnal,seasonal,and solar activity of the bottomside ionospheric profile parameters B0 and B1 are studied using electron density profiles measured over Wuhan(3..4°N, 114.4°E) of china with a DGS-2.6 Digisonde during *** are made with the International Reference Ionosphere model(IRI-2.01) using both the standard option(B0-Tab and B1-Tab) and the Gulyaeva’s option(B0-Gul and B1-Gul).The results show that:(1) observed B0 has distinct diurnal and seasonal variations,while observed B1 changes little with *** value of B0 is larger in summer than that in equinox and winter,especially for *** winter and equinox,B0 also presents morning and afternoon collapses as reported by Lei et al(2.04).(2. B0 increases about 18.6 km from low solar activity(LSA) to high solar activity(HSA).B1 in HSA is smaller than that in LSA before 10:00 LT and with an opposite tendency during the rest time.(3. Observed B0 is in better agreement with B0-Gul than with B0-Tab,though the B0-Gul overestimates during 09:00 to 17:00 LT in equinox and ***-Tab is 12.2. km larger than the observations over Wuhan almost all the ***,B1-Tab is in good agreement with the observations.

关键词： Low latitude ionosphere DGS-2.6 Digisonde IRI model Modeling and forecasting

Palaeogeothermal response and record of the effusing of Emeishan basalts in the Sichuan basin

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Palaeogeothermal response and record of the effusing of Emei...

中国科学院地质与地球物理研究所第十届(2.10年度)学术年会

作者： ZHU ChuanQing~(1,2.),XU Ming~(1,2.,YUAN YuSong~3.ZHAO YongQing~4,SHAN JingNan~(1,2., HE ZhiGuo~5,TIAN YunTao~(1,2. & HU ShengBiao~1 1 Institute of Geology and Geophysics,Chinese Academy of Sciences,beijing 10002.,china 2.The {2. university of Chinese Academy of Sciences,beijing 100049,china 3.Exploration and Production Research Institute,SINOPEC,beijing 100083.china 4 Exploration Department of South Company of Prospecting,SINOPEC,Chengdu 610041,china 5 Exploration and Development Research Institute of SINOPEC Southwest Branch,Chengdu 610081,china

Thermal history of the Sichuan basin is reconstructed based on vitrinite reflectance from boreholes in the basin using a paleo-heat flow *** results show that the Sichuan basin experienced a relatively low heat flow period in the Early Paleozoic,and an elevated paleo-heat flow,ranging 60-80 mW/m with a maximum as high as 100 mW/m around 2.9 Ma,from the beginning of the Late Paleozoic to the end of the early Permian,and a decreased paleo-heat flow from the late Permian to the late Triassic,and then maintained nearly stable to the *** Late Paleozoic paleo-heat flow was quite high where there were extensive Emeishan flood basalts or concealed basalts which erupted between the early and the late Permian,such as the southwestern and northeastern areas of the Sichuan *** to the distribution of paleo-heat flow,it can be inferred that,the northeastern Sichuan basin was also influenced by the Emeishan magmatic activity during the Dongwu movement though there was lack of Emeishan flood *** addition,the results of thermal history reconstruction of the Sichuan basin provide paleogeothermal evidence for the existence and onset of the Emaishan mantle plume.

关键词： vitrinite reflectance paleo-heat flow method thermal history Emeishan mantle plume Sichuan basin