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Prediction model for spring dust weather frequency in North china

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Science china Earth sciences 2008年第5期51卷 709-720页

作者： LANG XianMei center for Disastrous Climate Research and Prediction, institute of Atmospheric Physics, chinese academy of sciences, Beijing 100029,{3. center for Disastrous Climate Research and Prediction Institute of Atmospheric Physics Chinese Academy of Sciences Beijing 100029 China

It is of great social and scientific importance and also very difficult to make reliable prediction for dust weather frequency (DWF) in North china. In this paper, the correlation between spring DWF in Beijing and Tianjin observation stations, taken as examples in North china, and seasonally averaged surface air temperature, precipitation, Arctic Oscillation, Antarctic Oscillation, South Oscillation, near surface meridional wind and Eurasian westerly index is respectively calculated so as to construct a prediction model for spring DWF in North china by using these climatic factors. Two prediction models, i.e. model-I and model-II, are then set up respectively based on observed climate data and the 3.-year (1970 -2001) extra-seasonal hindcast experiment data as reproduced by the nine-level Atmospheric General Circulation Model developed at the{3. of Atmospheric Physics (IAP9L-AGCM). It is indicated that the correlation coefficient between the observed and predicted DWF reaches 0.93. in the model-I, suggesting a high prediction skill one season ahead. The corresponding value is high up to 0.948 for the subsequent model-II, which involves synchronous spring climate data reproduced by the IAP9L-AGCM relative to the model-I. The model-II can not only make more precise prediction but also can bring forward the lead time of real-time prediction from the model-I’s one season to half year. At last, the real-time predictability of the two models is evaluated. It follows that both the models display high prediction skill for both the interannual variation and linear trend of spring DWF in North china, and each is also featured by different advantages. As for the model-II, the prediction skill is much higher than that of original approach by use of the IAP9L-AGCM alone. Therefore, the prediction idea put forward here should be popularized in other regions in china where dust weather occurs frequently.

关键词： spring dust weather frequency prediction model iap9l-agcm hindcast experiment real-time prediction

Plasmacytoid dendritic cells in antiviral immunity and autoimmunity

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Science china(Life sciences) 2010年第2期53卷 172-182页

作者： TANG Fei1,2,DU Qiumei1,2 & LIU Yong-Jun3.1 center for Infection and Immunity,institute of Biophysics,chinese{3. of sciences,Beijing 100101,china 2 Graduate University of chinese academy of sciences,Beijing 100049,china 3.Department of Immunology and center for Cancer Immunology Research,University of Texas,M.D.Anderson Cancer center,Houston,Texas 7703.,USA 1. center for Infection and Immunity Institute of Biophysics Chinese Academy of Sciences Beijing 100101 China2. Graduate University of Chinese Academy of Sciences Beijing 100049 China3. Department of Immunology and Center for Cancer Immunology Research University of Texas M.D. Anderson Cancer Center Houston Texas 77030 USA

Plasmacytoid dendritic cells (pDCs) represent a unique and crucial immune cell population capable of producing large amounts of type I interferons (IFNs) in response to viral *** function of pDCs as the professional type I IFN-producing cells is linked to their selective expression of Toll-like receptor 7 (TLR7) and TLR9,which sense viral nucleic acids within the endosomal *** I IFNs produced by pDCs not only directly inhibit viral replication but also play an essential role in linking the innate and adaptive immune *** aberrant activation of pDCs by self nucleic acids through TLR signaling and the ongoing production of type I IFNs do occur in some autoimmune ***,pDC may serve as an attractive target for therapeutic manipulations of the immune system to treat viral infectious diseases and autoimmune diseases.

关键词： plasmacytoid dendritic cells type I interferon TLR7 TLR9 antiviral immunity autoimmune diseases

Re-Os(ICP-MS)dating of the massive sulfide ores from the Jinchuan Ni-Cu-PGE deposit

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Science china Earth sciences 2005年第10期48卷 1672-1677页

作者： YANG Gang1,2, DU Andao1, LU Jiren3. QU Wenjun1 & CHEN Jiangfeng2 1. National Research center of Geoanalysis, Beijing 10003., china 2. Laboratory for Earth Material Cycling, School of Earth and Space sciences, University of Science and Technology of china, Hefei 23.026, china 3. institute of Mineral Resource, chinese academy of Geological sciences, Beijing 10003., china National Research center of Geoanalysis Beijing china Laboratory for Earth Material Cycling School of Earth and Space Sciences University of Science and Technology of China Hefei China institute of Mineral Resource chinese academy of Geological{3. Beijing china

Massive sulfide ore from the Jinchuan Ni-Cu-PGE deposit was dated by Re-Os technique using Carius Tube digestion, Os distillation, Re extraction by acetone and ICP-MS measurement. An isochron giving an age of 83. ± 3. Ma, initial 187Os/188Os ratio of 0.279 ± 0.018 (MSWD = 1.7) and γOs = 13. ± 15 is obtained. The Re-Os age obtained agrees, within analytical uncertainties, with previous SHRIMP zircon U-Pb age of 827 ± 8 Ma (n=5, MSWD = 4.3.. The result suggests that the deposit was formed at Neoproterozoic and that the formation of the Jinchuan Ni-Cu-PGE sulfide deposit may be closely related to the plume activity, which were attributed to the breakup of the Rodinia supercontinent. The high γOs of the massive ores sug-gests that crustal material was involved in the formation of the Jinchuan deposit, however, the quantity of the added crustal material is less than 10%.

关键词： Jinchuan Ni-Cu-PGE deposit, Re-Os dating, ICP-MS.

Quantifying the effectiveness of SiO_2/Au light trapping nanoshells for thin film poly-Si solar cells

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Science china(Technological sciences) 2010年第8期53卷 2228-2231页

作者： BAI YiMing 1 ,WANG Jun 2 ,CHEN NuoFu 1,3.,YAO JianXi 1 ,YIN ZhiGang 3.,ZHANG Han 3., ZHANG XingWang 3.,HUANG TianMao 3.,WANG YanShuo 3.&YANG XiaoLi 3.1School of Renewable Energy Engineering,North china Electric Power University,Beijing 102206,china 2 National Engineering Research center for Optoelectronic Devices,{3. of Semiconductors, chinese academy of sciences,PO Box 912,Beijing 100083.china 3.Key Laboratory of Semiconductor Materials Science,{3. of Semiconductors, chinese academy of sciences,PO Box 912,Beijing 100083.china 1. School of Renewable Energy Engineering North China Electric Power University Beijing 102206 China2. National Engineering Research Center for Optoelectronic Devices Institute of Semiconductors Chinese Academy of Sciences PO Box 912 Beijing 100083 China3. Key Laboratory of Semiconductor Materials Science Institute of Semiconductors Chinese Academy of Sciences PO Box 912 Beijing 100083 China

In order to enhance light absorption of thin film poly-crystalline silicon(TF poly-Si)solar cells over a broad spectral range, and quantify the effectiveness of nanoshell light trapping structure over the full solar spectrum in theory,the effective photon trapping flux(EPTF)and effective photon trapping efficiency(EPTE)were firstly proposed by considering both the external quantum efficiency of TF poly-Si solar cell and scattering properties of light trapping *** EPTF,EPTE and scattering spectrum exhibit different behaviors depending on the geometric size and density of nanoshells that form the light trapping *** an optimum size and density of SiO2/Au nanoshell light trapping layer,the EPTE could reach up to 40%due to the enhancement of light trapping over a broad spectral range,especially from 500 to 800 nm.

关键词： thin film poly-crystalline silicon surface plasmons SiO2/Au nanoshell

Sea surface temperature east of Australia:A predictor of tropical cyclone frequency over the western North Pacific?

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chinese Science Bulletin 2011年第2期56卷 196-201页

作者： ZHOU BoTao 1,2 & CUI Xuan 3.1 National Climate center,china Meteorological Administration,Beijing 100081,china 2 Nansen-Zhu International Research center,institute of Atmospheric Physics,chinese academy of sciences,Beijing 100029,china 3.National Meteorological center,china Meteorological Administration,Beijing 100081,china National Climate center China Meteorological Administration Beijing China Nansen-Zhu International Research center Institute of Atmospheric Physics Chinese Academy of Sciences Beijing China National Meteorological center China Meteorological Administration Beijing China

The relationship between sea surface temperature (SST) east of Australia and tropical cyclone frequency over the western North Pacific (WNPTCF) is analyzed by use of observation *** WNPTCF from June to October is correlated negatively to spring SST east of *** the spring SST is in the positive phase,a cyclonic circulation anomaly in the upper troposphere and an anticyclonic circulation anomaly in the lower troposphere prevail over the western North Pacific from June to October,concurrent with an anomalous atmospheric subsidence and an enlarged vertical zonal wind *** conditions are unfavorable for tropical cyclone genesis,and thus WNPTCF *** negative phase of the spring SST east of Australia leads to more tropical cyclones over the western North *** spring SST east of Australia may give rise to simultaneous change in tropical atmospheric circulation via the teleconnection wave train,and then subsequently affect atmospheric circulation variation over the western North Pacific.

关键词：热带气旋北太平洋澳大利亚西部海面温度热带大气环流预测频率

Research on the multi-level intake water temperature effect of the Yalong River Jinping-I hydropower project

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Science china(Technological sciences) 2011年第S1期54卷 125-132页

作者： WU ShiYong 1,CAO Wei 1,WANG HongMei 1,SUN ShuangKe 2 &CHEN QiuWen 3.1 Ertan Hydropower Development Company,Ltd.,Chengdu 610051,china 2 china institute of Water Resources and Hydropower Research,Beijing 10003.,china 3.Research center for Eco-Environmental sciences,chinese academy of sciences,Beijing 100085,china 1. Ertan Hydropower Development Company Ltd. Chengdu 610051 China2. China Institute of Water Resources and Hydropower Research Beijing 100038 China3. Research Center for Eco-Environmental Sciences Chinese Academy of Sciences Beijing 100085 China

Based on the discussion of the multi-level intake application status of high dam reservoir,this paper takes the Jinping-I hydropower project reservoir in the Yalong River as an example,which is shaped by the highest 3.5 m high arch dam,and carries out the forecasting research on the reservoir temperature by numerical simulation and physical model *** paper studies the intake effect of withdrawing the surface warm water by the stoplog gates inlets and verifies the reliability of the mathematical model by comparative *** results show that for a high dam hydropower station,taking the appropriate multi-level intake measure can withdraw the surface warm water in the spawning season and provide a favorable environment for the fish *** technical ideas and implementation scheme are adopted in this *** can provide technical reference for the solutions of similar problems in the future and it also has important engineering significance on the research of water temperature in large deep reservoirs.

关键词： water temperature multi-level intake Jinping-I hydropower project

Principle of small target detection for hyperspectral imagery

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Science china Earth sciences 2007年第8期50卷 1225-1231页

作者： GENG XiuRui1,2,3.& ZHAO YongChao2,3.4 1 Research center for Remote Sensing and GIS, Department of Geography, Beijing Normal University, Beijing 100875, china 2 State Key Laboratory of Remote Sensing Science, chinese academy of sciences, Beijing 100101, china 3.institute of Erectronics, chinese academy of sciences, Beijing 100080, china 4 center for for Assessment and Monitoring of Forest and Environmental Resources and Division of Ecosystem sciences University of California Berkeley, CA 94720-3.14, USA 1. Research center for Remote Sensing and GIS Department of Geography Beijing Normal University Beijing 100875 China 2. State Key Laboratory of Remote Sensing Science Chinese Academy of Sciences Beijing 100101 China 3. institute of Erectronics Chinese Academy of Sciences Beijing 100080 China 4. center for for Assessment and Monitoring of Forest and Environmental Resources and Division of Ecosystem sciences University of California Berkeley CA 94720-3114 USA

This paper generalizes the progress of algorithms in small target detection for hyperspectral imaging, and finds that whitening the image is the key point of many methods in small target detection. An al-gorithm is presented to detect desired targets by converting large targets into small ones based on the weighted sample autocorrelation matrix.

关键词： hyperspectral whiten target detection

miRNAs modulate the drug response of tumor cells

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Science china(Life sciences) 2009年第9期52卷 797-801页

作者： WU XueMei1,3.& XIAO HuaSheng1,2 1 center of Functional Genomics,Key Laboratory of System Biology,Shanghai institutes for Biological sciences,{3. academy of sciences,Shanghai 20003.,china 2 National Engineering center for Biochip at Shanghai,Shanghai 201203.china 3.Graduate University of chinese academy of sciences,Shanghai 20003.,china center of Functional Genomics Key Laboratory of System Biology Shanghai Institutes for Biological Sciences Chinese Academy of Sciences Shanghai 200031 China National Engineering center for Biochip at Shanghai Shanghai 201203 China Graduate University of chinese academy of sciences Shanghai 200031 China

Chemotherapy is one of the major treatments of malignant carcinomas. However,its efficiency is affected by both intrinsic and acquired resistance to anticancer drugs. The cellular mechanisms of drug resistance include the overexpression of energy-dependent transporters that eject anticancer drugs from cells such as p-glycoprotein and multidrug resistance related protein (MRP),the mutation of drug targets,the activation of DNA repair pathways,the defects in cellular death pathways and so on. The genetic and epigenetic changes of these genes can lead to cancer drug resistance. Among these mechanisms,microRNAs (miRNAs) which are critical and essential for many important processes such as development,differentiation,and even carcinogenesis have been reported to regulate the chemosen-sitivity of tumor cells. In this paper we briefly review the relationship between miRNA and cancer drug resistance.

关键词： cancer drug resistance miRNAs

fMRI time series analysis based on stationary wavelet and spectrum analysis

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Progress in Natural Science:Materials International 2006年第11期16卷 1171-1176页

作者： ZHI Lianhe~ 1,2,3., ZHAO Xia~4, SHAN Baoci~1**, PENG Silong~5, YAN Qiang~1, YUAN Xiuli~1 and TANG Xiaowei~ 1,6 (1. Key Laboratory of Nuclear Analysis Techniques, institute of High Energy Physics, chinese academy of sciences, Beijing 100049, china 2. Graduate School of chinese academy of sciences, Beijing 100049, china 3. Department of Physics, Zhoukou Normal University, Zhoukou 466100, china 4. Research Imaging center, University of Texas Health Science center, San Antonio, Texas 78229, USA 5. National ASIC Design and Engineering center, institute of Automation, chinese academy of sciences, Beijing 100049, china 6. Department of Physics, Zhejiang University, Hangzhou 3.0027, china) [a]Key Laboratory of Nuclear Analysis Techniques Institute of High Energy Physics Chinese Academy of Sciences Beijing China [b]Graduate School of chinese academy of sciences Beijing China [c]Department of Physics Zhoukou Normal University Zhoukou China [d]Research Imaging center University of Texas Health Science Center San Antonio Texas USA [e]National ASIC Design and Engineering center Institute of Automation Chinese Academy of Sciences Beijing China [f]Department of Physics Zhejiang University Hangzhou China

The low signal to noise ratio (SNR) of functional MRI (fMRI) prefers more sensitive data analysis methods. Based on stationary wavelet transform and spectrum analysis, a new method with high detective sensitivity was developed for analyzing fMRI time series, which does not require any prior assumption of the characteristics of noises. In the proposed method, every component of fMRI time series in the different time-frequency scales of stationary wavelet transform was discerned by the spectrum analysis, then the components from noises were removed using the stationary wavelet transform, finally the components of real brain activation were detected by cross-correlation analysis. The results obtained from both simulated and in vivo visual experiments illustrated that the proposed method has much higher sensitivity than the traditional cross-correlation method.

关键词： fMRI stationary wavelet transform spectrum analysis data analysis.