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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{2.,Hefei 2.002.,china 3 Laboratory of visual {4. processing,Institute of biophysics,chinese academy of sciences,beijing {12.,china Hefei National Laboratory for Physical sciences at Microscale and School of Life Science University of Science and Technology of China Hefei China Laboratory of visual information {2. Institute of Biophysics Chinese Academy of Sciences Beijing China

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.135 and 0.074.vs O.10,respectively),accompanied by significant increases in spontaneous(2..4.vs 17.5)and evokedactivity(preferred:4..2.vs 38.1;average:2..1 vs 2..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

An efficient quantum secret sharing protocol with orthogonal product states

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Science china(Physics,Mechanics & Astronomy) 2007年第3期50卷 331-338页

作者： YANG YuGuang1,2. WEN QiaoYan3 & ZHU FuChen4.1 School of Computer, beijing University of Technology, beijing 10002., china 2.State Key Laboratory of information Security, Graduate University of {4. academy of sciences, beijing 10002., china 3 School of Science, beijing University of Posts and Telecommunications, beijing 100876, china 4.National Key Laboratory for Modern Communications, Chengdu 61004., china School of Computer Beijing University of Technology Beijing China State Key Laboratory of information Security Graduate University of Chinese Academy of Sciences Beijing China School of Science Beijing University of Posts and Telecommunications Beijing China National Key Laboratory for Modern Communications Chengdu China

An efficient quantum secret sharing protocol with orthogonal product states in the 33 Hilbert space is presented. The particles in the orthogonal product states form two particle sequences. One sequence is sent to Bob and the other is sent to Charlie after rearranging the particle orders. With the help of Alice, Bob and Charlie make the corresponding local measurement to obtain the information of the or- thogonal product states prepared. This protocol has many distinct features such as great capacity and high efficiency.

关键词： quantum secret sharing orthogonal product state orthogonal measurement

Perceptual video hashing robust against geometric distortions

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Science china(information {2.) 2012年第7期55卷 1520-1527页

作者： XIANG ShiJun 1,4.,YANG JianQuan 2.& HUANG JiWu 3 1 School of information Science and Technology,Jinan University,Guangzhou 510632.{2. 2.Shenzhen Institutes of Advanced Technology,chinese academy of {4.,Shenzhen 518055,{2. 3 School of information Science and Technology,Sun Yat-sen University,Guangzhou 5102.5,{2. 4.State Key Laboratory of information Security,Institute of Software,chinese academy of {4.,beijing 10004.,{2. School of information Science and Technology Jinan University Guangzhou China State Key Laboratory of information Security Institute of Software Chinese Academy of Sciences Beijing China Shenzhen Institutes of Advanced Technology Chinese Academy of Sciences Shenzhen China School of information Science and Technology Sun Yat-sen University Guangzhou China

In this paper,we propose a robust perceptual hashing algorithm by using video luminance histogram in *** underlying robustness principles are based on three main aspects:1) Since the histogram is independent of position of a pixel,the algorithm is resistant to geometric deformations; 2. the hash is extracted from the spatial Gaussian-filtering low-frequency component for those common video processing operations such as noise corruption,low-pass filtering,lossy compression,etc.; 3) a temporal Gaussian-filtering operation is designed so that the hash is resistant to temporal desynchronization operations,such as frame rate change and *** a result,the hash function is robust to common geometric distortions and video processing *** results show that the proposed hashing strategy can provide satisfactory robustness and uniqueness.

关键词： video hashing geometric distortion histogram Gaussian filtering

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 361005, china 2.Kunming Institute of Zoology, {2. academy of sciences, Kunming 6502.3, china 3 State Key Laboratory of Brain and Cognitive Science, Institute of biophysics, {2. academy of sciences, beijing 1001001, china 4.School of information Science, Yunnan University, Kunming 6502.3, china Lab of Mind Art and Computation Xiamen University Xiamen China Kunming Institute of Zoology Chinese Academy of Sciences Kunming China State Key Laboratory of Brain and Cognitive Science Institute of Biophysics Chinese Academy of Sciences Beijing China School of information Science Yunnan University Kunming 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

Fast Fourier-Galerkin methods for first-kind logarithmic-kernel integral equations on open arcs

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Science china Mathematics 2010年第1期53卷 1-22页

作者： WANG Bo1,WANG Rui2.& XU YueSheng3,4.1academy of Mathematics and Systems Science,{2. academy of sciences,{4. 100190,china 2.chool of information Science and Engineering,Graduate University of the {2. academy of sciences,{4. 100190,china 3Department of Mathematics,Syracuse University,Syracuse,NY 132.0},USA 4.epartment of Scientific Computing and Computer Applications,Sun Yat-sen University,Guangzhou 5102.5,china academy of Mathematics and Systems Science Chinese Academy of Sciences Beijing China School of information Science and Engineering Graduate University of the Chinese Academy of Sciences Beijing China Department of Mathematics Syracuse University Syracuse USA Department of Scientific Computing and Computer Applications Sun Yat-sen University Guangzhou China

We propose a fully discrete fast Fourier-Galerkin method for solving an integral equation of the first kind with a logarithmic kernel on a smooth open arc,which is a reformulation of the Dirichlet problem of the Laplace equation in the *** optimal convergence order and quasi-linear complexity order of the proposed method are established.A precondition is *** this method with an efficient numerical integration algorithm for computing the single-layer potential defined on an open arc,we obtain the solution of the Dirichlet problem on a smooth open arc in the *** examples are presented to confirm the theoretical estimates and to demonstrate the efficiency and accuracy of the proposed method.

关键词： Dirichlet problem open arc singular boundary integral equations Fourier-Galerkin methods logarithmic potentials

Quantum threshold group signature

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Science china(Physics,Mechanics & Astronomy) 2008年第10期51卷 1505-1514页

作者： YANG YuGuang1,2.3 & WEN QiaoYan4.1 College of Computer Science and Technology, beijing University of Technology, beijing 10012.0} china 2.State Key Laboratory of Integrated Services Network, Xidian University, Xi’an 710071, china 3 State Key Laboratory of {4. Security (Graduate University of chinese academy of sciences), beijing 10004., china 4.State Key Laboratory of Networking and Switching Technology, beijing University of Posts and Tele-communications, beijing 100876, china College of Computer Science and Technology Beijing University of Technology Beijing China State Key Laboratory of Integrated Services Network Xidian University Xi’an China State Key Laboratory of information Security Graduate University of Chinese Academy of Sciences Beijing China State Key Laboratory of Networking and Switching Technology Beijing University of Posts and Telecommunications Beijing China

In most situations, the signer is generally a single person. However, when the message is written on behalf of an organization, a valid message may require the approval or consent of several persons. Threshold signature is a solution to this problem. Generally speaking, as an authority which can be trusted by all members does not exist, a threshold signature scheme without a trusted party appears more attractive. Following some ideas of the classical Shamir’s threshold signature scheme, a quantum threshold group signature one is proposed. In the proposed scheme, only t or more of n persons in the group can generate the group signature and any t-1 or fewer ones cannot do that. In the verification phase, any t or more of n signature receivers can verify the message and any t-1 or fewer receivers cannot verify the validity of the signature.

关键词： threshold quantum signature trusted party quantum cryptography

Threshold quantum secret sharing between multi-party and multi-party

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Science china(Physics,Mechanics & Astronomy) 2008年第9期51卷 1308-1315页

作者： YANG YuGuang1,2.3 & WEN QiaoYan4.1 College of Computer Science and Technology,beijing University of Technology,beijing 10012.0}china 2.State Key Laboratory of Integrated Services Network,Xidian University,Xi’an 710071,china 3 State Key Laboratory of {4. Security (Graduate University of chinese academy of sciences),beijing 10004.,china 4.State Key Laboratory of Networking and Switching Technology,beijing University of Posts and Tele-communications,beijing 100876,china College of Computer Science and Technology Beijing University of Technology Beijing China State Key Laboratory of Integrated Services Network Xidian University Xi’an China State Key Laboratory of information Security (Graduate University of chinese {2. of sciences) Beijing China State Key Laboratory of Networking and Switching Technology Beijing University of Posts and Telecommunications Beijing China

A threshold quantum secret sharing (TQSS) scheme between multi-party and multi-party was proposed using a sequence of single photons,which is useful and efficient when the parties of communication are not all present. We described the process of this TQSS scheme and discussed its security. It was shown that entan-glement is not necessary for quantum secret sharing. Moreover,the theoretic effi-ciency was improved to approach 100% as almost all the instances can be used for generating the private key,and each photon can carry one bit of information. This protocol is feasible with the present-day technique.

关键词： threshold quantum secret sharing quantum cryptography single photon multi-party and multi-party

Salient region detection and segmentation for general object recognition and image understanding

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Science china(information {2.) 2011年第12期54卷 2481-2490页

作者： HUANG TieJun 1 , TIAN YongHong 1 , LI Jia 2.& YU HaoNan 11 National Engineering Laboratory for Video Technology, School of Electrical Engineering and Computer Science, Peking University, beijing 100871, china 2.Key Laboratory of Intelligent {2. processing, Institute of Computing Technology, {4. academy of sciences, beijing 100190, china National Engineering Laboratory for Video Technology School of Electrical Engineering and Computer Science Peking University Beijing China Key Laboratory of Intelligent information processing Institute of Computing Technology Chinese Academy of Sciences Beijing China

General object recognition and image understanding is recognized as a dramatic goal for computer vision and multimedia retrieval. In spite of the great efforts devoted in the last two decades, it still remains an open problem. In this paper, we propose a selective attention-driven model for general image understanding, named GORIUM (general object recognition and image understanding model). The key idea of our model is to discover recurring visual objects by selective attention modeling and pairwise local invariant features matching on a large image set in an unsupervised manner. Towards this end, it can be formulated as a four-layer bottom-up model, i.e., salient region detection, object segmentation, automatic object discovering and visual dictionary construction. By exploiting multi-task learning methods to model visual saliency simultaneously with the bottom-up and top-down factors, the lowest layer can effectively detect salient objects in an image. The second layer exploits a simple yet effective learning approach to generate two complementary maps from several raw saliency maps, which then can be utilized to segment the salient objects precisely from a complex scene. For the third layer, we have also implemented an unsupervised approach to automatically discover general objects from large image set by pairwise matching with local invariant features. Afterwards, visual dictionary construction can be implemented by using many state-of-the-art algorithms and tools available nowadays.

关键词： object recognition image understanding visual saliency salient object segmentation visual dictionary

Bursting of Morris-Lecar neuronal model with current-feedback control

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Science china(Technological sciences) 2009年第3期52卷 771-781页

作者： DUAN LiXia1, LU QiShao2.& CHENG DaiZhan3 1 College of Science, North china University of Technology, beijing 1001{2., china 2.School of Science, beijing University of Aeronautics and Astronautics, beijing 100191, china 3 Institute of Systems Science, chinese academy of sciences, beijing 100190, china College of Science North China University of Technology Beijing China School of Science Beijing University of Aeronautics and Astronautics Beijing China Institute of Systems Science Chinese Academy of Sciences Beijing China

The Morris-Lecar (ML) neuronal model with current-feedback control is considered as a typical fast-slow dynamical system to study the combined influences of the reversal potential VCa of Ca2. and the feedback current I on the generation and transition of different bursting oscillations. Two-parameter bifurcation analysis of the fast subsystem is performed in the parameter (I, VCa)-plane at first. Three important codimension-2.bifurcation points and some codimension-1 bifurcation curves are obtained which enable one to determine the parameter regions for different types of bursting. Next, we further divide the control parameter (V0, VCa)-plane into five different bursting regions, namely, the "fold/fold" bursting region R1, the "fold/Hopf" bursting region R2. the "fold/homoclinic" bursting region R3, the "subHopf/homoclinic" bursting region R4.and the "subHopf/subHopf" bursting region R5, as well as a silence region R6. Codimension-1 and -2.bifurcations are responsible for explanation of transition mechanisms between different types of bursting. The results are instructive for further understanding the dynamical behavior and mechanisms of complex firing activities and information {2. in biological nervous systems.

关键词： neuron bursting bifurcation fast-slow dynamics analysis codimension