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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, Institute of {4., 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., Institute of {4., 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, Institute of Computing Technology, {3. {4. of sciences, beijing 100080, china 2 laboratory of visual information processing, Institute of biophysics, {3. {4. 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

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., Institute of {4., 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

Chronic morphine exposure induces degradation of receptive field properties of LGN cells in cats

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Acta Pharmacologica Sinica 2005年第9期26卷 1034-1038页

作者： Li-hua HE~2 Guang-xing LI~2 Xiang-mi LI~2 Yi-feng ZHOU~(2,3.4.2 Hefei National laboratory for Physical sciences at Microscale and School of Life Science,University of Science and Technology of{3.,Hefei 23.027,china 3.laboratory of visual information processing,Institute of biophysics,chinese academy of sciences,{13. 100101,china HefeiNationallaboratoryforPhysicalsciencesatMicroscaleandSchoolofLifeScience UniversityofScienceandTechno

Aim:To investigate the effect of chronic morphine exposure on the receptive fieldproperties of lateral geniculate nucleus(LGN)neurons in ***:Catswere injected with morphine(10 mg/kg)or saline twice daily,for 10 ***,extracellular single-unit recording techniques were used to examine the sensitivityof LGN neurons to visual stimuli in chronic morphine-treated and ***:Compared with saline-treated cats(as controls),LGN neurons inmorphine-treated cats had decreased signal-to-noise ratios(1.9 vs 3.1 ),and orien-tation and direction sensitivity(0.103.vs O.13. and 0.074.vs O.10,respectively),accompanied by significant increases in spontaneous(27.4.vs 17.5)and evokedactivity(preferred:4..2 vs 3..1;average:28.1 vs 22.3..Conclusion:Chronic mor-phine exposure can lead to the functional degradation of LGN neurons in cats,which might result from the effects of chronic morphine exposure on inhibitoryneurotransmission.

关键词： direction sensitivity orientation sensitivity signal-to-noise ratio spontaneous response evoked response

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

The correspondence between the concepts in description logics for contexts and formal concept analysis

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Science china(information sciences) 2012年第5期55卷 1106-1122页

作者： MA Yue 1,2,SUI YueFei 1 & CAO CunGen 1 1 Key laboratory of Intelligent information processing,Institute of Computing Technology,{3. {4. of sciences,beijing 100190,china 2 Graduate University of {3. {4. of sciences,beijing,china 1. Key laboratory of Intelligent information processing Institute of Computing Technology Chinese Academy of Sciences Beijing 100190 China2. Graduate University of Chinese Academy of Sciences Beijing 100049 China

Formal concept analysis (FCA) and description logic (DL) are meant to be formalizations of concepts.A formal concept in the former consists of its intent and extent,where the intent is the set of all the attributes shared by each object in the extent of the concept,and the extent is the set of all the objects sharing each property in the intent of the concept.A concept in the latter formalization is simply a concept name,the interpretation of which is a subset of a *** consider the correspondence between concepts in both formalizations,a multi-valued formal context must be represented both as a knowledge base and as a model of the DL for contexts,where concepts are decomposed into tuple concepts C,interpreted as a set of tuples and value concepts V,interpreted as a set of attribute-value *** show that there is a difference between the interpretation of concepts R.V /R.C and the Galois connection between the extent/intent of formal concepts in *** to the Galois connection,there should be concepts of the form + R.V and + R.C inter-preted in FCA,and hence the logical language L for DL is extended to be L + together with + as a constructor so that + R.V and + R.C are well-defined ***,according to the interpretation in DL there should be pseudo concepts in FCA so that the interpretation of concepts R.V /R.C is the extent/intent of pseudo *** correspondence between formal concepts and concepts in L +,and between pseudo concepts and concepts in L are presented in this paper.

关键词： description logic formal concept analysis concept attribute/role

Configural processing of different topologically structured figures:an ERP Study

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Science china(Life sciences) 2009年第12期52卷 1198-1204页

作者： ZHANG JunJun1, ZHU WeiNa2,3.4. DING XiaoJun1, ZHOU ChangLe1, HU XinTian2,3.& MA YuanYe2,3. 1 Lab of Mind, Art and Computation, Xiamen University, Xiamen 3.1005, china 2 Kunming Institute of Zoology, chinese {3. of sciences, Kunming 650223. china 3.State Key laboratory of Brain and Cognitive Science, Institute of biophysics, chinese {3. of sciences, beijing 1001001, china 4.School of information Science, Yunnan University, Kunming 650223. china 1. Lab of Mind Art and Computation Xiamen University Xiamen 361005 China 2. Kunming Institute of Zoology Chinese Academy of Sciences Kunming 650223 China 3. State Key laboratory of Brain and Cognitive Science Institute of Biophysics Chinese Academy of Sciences Beijing 1001001 China 4. School of information Science Yunnan University Kunming 650223 China

According to Chen's theory, topological differences are perceived faster than feature differences in early visual perception. We hypothesized that topological perception is caused by the sensitivity in discriminating figures with and without "holes" . An ERP experiment was conducted utilizing a passive paradigm to investigate the differences in perceiving figures with "hole" and with "no-hole" . The results showed differences in N170 components between figures with "holes" and with "no-holes" . The inversion of the "hole" could influence the latency of N170, but the inversion of the "no-hole" could not, which indicated that global features are processed first in the "hole" perception whilst local features are given priority to the "no-hole" perception. This result was similar to studies concerning face and non-face objects, suggesting a configural processing of the "hole" .

关键词： visual evoked potential topological perception N170

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果蝇学习记忆行为的分子机制

生物化学与生物物理进展 2002年第5期29卷 670-673页

作者：温艾刘力中国科学院生物物理研究所脑与认知科学研究中心中国科学院视觉信息加工重点实验室北京100101

分子遗传学技术的应用一方面发展了新的神经组织学方法 ,使果蝇脑中的细微结构得以展示 ;另一方面 ,对记忆从形成到提取过程中信息处理的研究 ,表明蘑菇体可能在形成长时程记忆方面起重要作用 ,而一对背内侧核团 (dorsalpairedmedialcel... 详细信息

分子遗传学技术的应用一方面发展了新的神经组织学方法 ,使果蝇脑中的细微结构得以展示 ;另一方面 ,对记忆从形成到提取过程中信息处理的研究 ,表明蘑菇体可能在形成长时程记忆方面起重要作用 ,而一对背内侧核团 (dorsalpairedmedialcells)与蘑菇体之间的信息传递对于记忆的“提取 (retrieval)”是至关重要的 .行为功能检测为视觉信号整和的研究提供了新的实验依据。

关键词：果蝇学习记忆行为分子机制分子神经生物学