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Antioxidant effects of green tea polyphenols

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chinese Science Bulletin 2003年第4期48卷 315-319页

作者： ZHAO Baolu laboratory of visual information {3., Research Centers of Brain and Cognitive Science, {4. of biophysics, chinese academy of sciences, beijing 100101, China laboratory of visual information {3. Research Centers of Brain and Cognitive Science Institute of Biophysics Chinese Academy of Sciences Beijing 100101 China

The unprecedented interest in the antioxidant activity of green tea polyphenols (GTP) is due to the appar-ent health benefits of tea drinking and the experimental re-sults with the polyphenols. The results suggest that the gal-loylated catechins show stronger antioxidant effect than that of nongalloylated catechins and the double bond in C ring also plays an important role in this effect. There are synergic effects between different catechins and the antioxidant effect of (+)-epimers is stronger than that of (-)-epimers. The active site to scavenge free radicals mainly locates in p-hydroxyl of phenol in gallic acid and hydroxyl of phenol in the pyrane also shows activity. The large p bond in chromane and benzene ring of catechin is the structure base for their anti-oxidant effects. The prevent effect of GTP against diseases and their redox regulation in cell signal pathway are very important to be studied in the future.

关键词：绿茶茶多酚天然抗氧化剂抗氧化作用生物类黄酮自由基抗衰老

Binaurality and azimuth tuning of neurons in the auditory cortex of the big brown bat

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chinese Science Bulletin 2002年第12期47卷 1024-1027页

作者： SHEN Junxian & CHEN QicaiCenter for Brain and Cognitive Science, laboratory of visual information {3., {4. of biophysics, chinese academy of sciences, beijing 100101, China Department of Biology, Central China Normal University, Wuhan 4.0070, Lab. of visual Info. processing Institute of Biophysics Chinese Academy of Sciences Beijing 100101 China

By using a combined closed and free-field stimulation system, binaurality and azimuth tuning of the neurons in the auditory cortex of the big brown bat, Epte-sicus fuscus, were studied. A variety of azimuth-tuning functions were demonstrated for the binaural neurons. The large majority of EE (contralateral and ipsilateral excitatory) neurons exhibited azimuth selectivity with the best azimuths (BA) at contralateral 3.°-4.°, some at ipsilateral 20°-4.° and preferred azimuth ranges (PAR, response amplitude >75% of maximum) between 8° and 4.°. Sound source azimuths strongly modulate spike counts with a mean modulation depth of 83.8% for EE neurons. EI (contralateral excitatory and ipsilateral inhibitory) neurons have simple azimuth tuning with BA located at contralateral 20°-4.° and a broad PAR ranged from 3.° to 55°. The present results suggest that azimuth-tuning characteristics of binaural neurons in the auditory cortex of the bat are of significance for acoustic behaviour.

关键词： bat auditory cortex binaural neurons azimuth tuning.

The universal fuzzy logical framework of neural circuits and its application in modeling primary visual cortex

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Science China(Life sciences) 2008年第10期51卷 902-912页

作者： HU Hong1, LI Su2, WANG YunJiu2, QI XiangLin2 & SHI ZhongZhi1 1 Key laboratory of Intelligent information processing, {3. of Computing Technology, {4. academy of sciences, beijing 100080, China 2 laboratory of visual information processing, {3. of {13., {4. academy of sciences, beijing 100101, China 1. Key laboratory of Intelligent information processing Institute of Computing Technology Chinese Academy of Sciences Beijing 100080 China 2. laboratory of visual information {3. Institute of Biophysics Chinese Academy of Sciences Beijing 100101 China

Analytical study of large-scale nonlinear neural circuits is a difficult task. Here we analyze the function of neural systems by probing the fuzzy logical framework of the neural cells' dynamical equations. Al- though there is a close relation between the theories of fuzzy logical systems and neural systems and many papers investigate this subject, most investigations focus on finding new functions of neural systems by hybridizing fuzzy logical and neural system. In this paper, the fuzzy logical framework of neural cells is used to understand the nonlinear dynamic attributes of a common neural system by abstracting the fuzzy logical framework of a neural cell. Our analysis enables the educated design of network models for classes of computation. As an example, a recurrent network model of the primary visual cortex has been built and tested using this approach.

关键词： nonlinear dynamical system fuzzy logic visual cortex

Monitoring of rice crop using ENVISAT ASAR data

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Science China Earth sciences 2006年第7期49卷 755-763页

作者： DONG Yanfang1, 2, SUN Guoqing1,3.& PANG Yong4.1. State Key laboratory of Remote Sensing Science, institute of Remote Sensing Applications, {3. {3. of {4., beijing 100101, China 2. Graduate University of {3. {3. of {4., beijing 10003., China 3. Department of Geography, University of Maryland, College Park, MD 2074., USA 4. Forest Remote Sensing Lab, Research institute of Forest Resource and information Technology, {3. {3. of For-estry, beijing 100091, China 1. State Key laboratory of Remote Sensing Science Institute of Remote Sensing Applications Chinese Academy of Sciences Beijing 100101 China 2. Graduate University of chinese academy of sciences Beijing 100039 China 3. Department of Geography University of Maryland College Park MD 20742 USA 4. Forest Remote Sensing Lab Research Institute of Forest Resource and Information Technology Chinese Academy of Forestry Beijing 100091 China

Because of the cloudy conditions during the rice growth period, rice is one of the agri-cultural crops most suited to monitoring with the SAR instruments. Backscatter response measured by SAR is correlated with rice conditions, including height, density, biomass and structure, which are variable at different growing stages. In this paper, multi-date ENVISAT ASAR Alternating Polarization Mode (APMode) imageries were acquired during the rice crop growing cycle. At the same time, the rice parameters were measured in field. A continuous canopy model was used to compute the back-scattering from rice fields during the growth cycle, and the relationship between rice parameters and radar backscattering coefficients from both ASAR and modeling was analyzed. The effects of polari-zation, incidence angle and polarization on radar backscattering coefficients were analyzed. It was found that simulated radar backscatter has similar trends as ASAR data. This will be meaningful for the further research of rice parameters estimation from ASAR data. Different features show signifi-cantly different signatures in ASAR images and they follow some certain laws, so rice area can be accurately mapped by using multi-temporal SAR images, then rice yield can be estimated.

关键词： rice, ASAR, radar backscattering, model.

Influence of prolonged optic flow stimuli on spontaneous activities of cat PMLS neurons

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chinese Science Bulletin 2003年第8期48卷 786-790页

作者： XU Ying, LI Bing & DIAO Yuncheng laboratory of visual information {3., {4. of biophysics, chinese academy of sciences, beijing 100101, China Correspondence should be addressed to Li Bing (e-mail: lib@sun5.ibp. ***) laboratory of visual information {3. Institute of Biophysics Chinese Academy of Sciences China

Changes in neuronal spontaneous activities after prolonged optic flow stimulation (using the three basic flow modes: translation, radiation and rotation) were inves-tigated by extracellular single-unit recording in cortical area PMLS of the cat. The results showed that the evoked re-sponses decreased with the prolongation of visual stimuli, and the spontaneous activities usually dropped to a lower level after the stimuli were withdrawn. Generally, the reduc-tion in spontaneous activities was larger after adaptation in the preferred direction than in the non-preferred direction. This difference was much pronounced to translation stimuli, but relatively insignificant to radiation and rotation. These points suggest that non-specific fatigue may act as the key factor in adaptation to simple translation, while some kinds of more complicated, direction-specific mechanism may be involved in adaptation to the complex optic flow patterns. In addition, PMLS may play an important role in perception and adaptation to complex motion and the relevant motion after-effects.

关键词：光流刺激自发性活动 PMLS神经细胞猫

Seasonal patterns of spatial differentiation of landcover change in China

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chinese Science Bulletin 1999年第4期44卷 362-364页

作者： CHEN YufengState Key laboratory of Resource and Environment information System , institute of Geography, {3. {4. of sciences, beijing 100101, China State Key laboratory of Resource and Environment information System Institute of Geography Chinese Academy of Sciences Beijing China

Using the 1°×1° NOAA AVHRR NDVI data set in China, an index on the spatial different gradient of landcover is created. Then based on the index and supported by the geographical information system, it is revealed through principal component and factor analyses methods that there exist four types of seasonal patterns of spatial differentiation of landcover change in China, i.e. November to next March type, June to September type, May or October type and April type.

关键词： landcover spatial differentiation seasonal pattern.

Control of atmospheric CO_2 concentrations by 2050: A calculation on the emission rights of different countries

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Science China Earth sciences 2009年第10期52卷 1447-1469页

作者： DING ZhongLi1, DUAN XiaoNan2, GE QuanSheng3.& ZHANG ZhiQiang4.1 institute of Geology and Geophysics, chinese {3. of {3., {4. 100029, China 2 The General Office of chinese {3. of {3., {4. 100864. China 3.institute of Geographic {3. and Natural Resources Research, chinese {3. of {3.,{14., China 4.The Lanzhou Branch of the National Science Library, the Scientific information Center for Resources and Environment, Lanzhou 73.000, China institute of Geology and Geophysics Chinese Academy of Sciences Beijing 100029 China The General Office of chinese academy of sciences Beijing 100864 China institute of Geographic sciences and Natural Resources Research Chinese Academy

This paper is to provide quantitative data on some critical issues in anticipation of the forthcoming international negotiations in Denmark on the control of atmospheric CO2 concentrations. Instead of letting only a small number of countries dominate a few controversial dialogues about emissions reductions, a comprehensive global system must be established based on emissions allowances for different countries, to realize the long-term goal of controlling global atmospheric CO2 concentrations. That a system rooted in "cumulative emissions per capita," the best conception of the "common but differentiated responsibilities" principle affirmed by the Kyoto Protocol according to fundamental standards of fairness and justice, was demonstrated. Based on calculations of various countries' cumulative emissions per capita, estimates of their cumulative emissions from 1900 to 2005, and their annual emissions allowances into the future (2006―2050), a 4.0 ppmv atmospheric CO2 concentration target was set. According to the following four objective indicators―total emissions allowance from 1900 to 2050, actual emissions from 1900 to 2005, emissions levels in 2005, and the average growth rate of emissions from 1996 to 2005―all countries and regions whose population was more than 3.0000 in 2005 were divided into four main groups: countries with emissions deficits, countries and regions needing to reduce their gross emissions, countries and regions needing to reduce their emissions growth rates, and countries that can maintain the current emissions growth rates. Based on this proposal, most G8 countries by 2005 had already expended their 2050 emissions allowances. The accu-mulated financial value based on emissions has reached more than 5.5 trillion US dollars (20 dollars per ton of CO2). Even if these countries could achieve their ambitious emissions reduction targets in the future, their per capita emissions from 2006 to 2050 would still be much higher than those of developing coun

关键词： international negotiations on climate change cumulative emissions per capita emission allowance

配对螺旋样纤维(PHF)-Tau与神经细胞的死亡

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生物化学与生物物理进展 2001年第4期28卷 441-443页

作者：聂春来视觉信息加工开放实验室

神经纤维缠结 (neurofibrillarytangles ,NFT)是老年性痴呆病的重要病理特征 ,人类神经tau分子聚集形成的配对螺旋样纤维 (pairedhelicalfilaments ,PHF)是NFT的主要成分 .最近研究表明 ,PHF与神经细胞的坏死和程序化死亡密切相关。

关键词：神经tau 氧自由基配对螺旋样纤维老年性痴呆病神经细胞死亡

Discovery of immune related factors in Fenneropenaeus chinensis by annotation of ESTs

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Progress in Natural Science:Materials International 2004年第1期14卷 48-55页

作者： SHEN Yaoqing 1,2 , XIANG Jianhai 1*, WANG Bing 1,2 , LI Fuhua 1 and TONG Wei 3.1. Experimental Marine Biology laboratory, institute of Oceanology, chinese {3. of {4., Qingdao 266071,China 2. Graduate School of the chinese {3. of {4., beijing 10003., China 3. Genomics & Bioinformatics institute, chinese {3. of {4., beijing 1013.0, China) chinese Acad Sci Inst Oceanol Expt Marine Biol Lab Qingdao 266071 Peoples R China chinese Acad Sci Grad Sch Beijing 100039 Peoples R China chinese Acad Sci Geonom & Bioinformat Inst Beijing 101300 Peoples R China

A total of 104.6 expressed sequence tags (ESTs) are obtained by a large scale sequencing of a cDNA library from cephalothorax of adult Fenneropenaeus chinensis . An EST analysis platform was built up based on local computers and bioinformatic techniques were used to annotate these ESTs in order to promptly find possible functional genes, especially for immune related factors. About 4. of the ESTs show similarity to the coding sequences of such factors, including lectin, serine protease, serpin, lysozyme, etc. These ESTs provide a partial profile of the immune system in F. chinensis and useful {3. for further study on these genes.

关键词： Fenneropenaeus chinensis bioinformatics ESTs immune factors