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Caspase Family Proteases and Apoptosis

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Acta Biochimica et Biophysica Sinica 2005年第11期37卷 719-727页

作者： Ting-Jun FAN Li-Hui HAN Ri-Shan CONG Jin LIANG college of Marine Life sciences,Division of Life science and technology,Ocean university of china,qingdao 266003,china college of Chemistry & Chemical Engineering,Ocean university of china,qingdao 266003,china collegeofMarineLifesciences DivisionofLifeScienceandTechnologyOceanUniversityofChinaQingdao266003China

Apoptosis,or programmed cell death,is an essential physiological process that plays a criticalrole in development and tissue *** progress of apoptosis is regulated in an orderly way by aseries of signal cascades under certain *** caspase-cascade system plays vital roles in theinduction,transduction and amplification of intracellular apoptotic ***,closely associated withapoptosis,are aspartate-specific cysteine proteases and members of the interleukin-1β-converting *** activation and function of caspases,involved in the delicate caspase-cascade system,are regu-lated by various kinds of molecules,such as the inhibitor of apoptosis protein,Bcl-2 family proteins,calpain,and Ca2+,Based on the latest research,the members of the caspase family,caspase-cascade system andcaspase-regulating molecules involved in apoptosis are reviewed.

关键词： caspase apoptosis interleukin-1β-converting enzyme family inhibitor of apoptosis protein Bcl-2 family

Simulation and Evaluation for Contention-Collision Cancellation Access Mode based on OPNet

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Simulation and Evaluation for Contention-Collision Cancellat...

Robustness and breakup of the spiral wave in a two-dimensional lattice network of neurons

2009中国控制与决策会议

作者： Lijun Sun School of information science and technology,qingdao university of science and technology,qingdao,266061

＜正＞As an important access mode in multi-star local area network（LAN）,Contention-Collision Cancellation （C-CC） access mode is classified six types of system model,and only type I of C-CC access mode has been modeled by *** this paper,typeⅢand typeⅤmodels of C-CC access mode are done simulation using by OPNet Modeler,and the characteristic and modeling process of these 3 type system models are *** running the simulation,we get 3 main performance parameters:packet delay,the queue size of central node,and ***,these 3 type models of C-CC access mode are evaluated and analyzed.

关键词： Simulation modeling Multi-star LAN C-CC access mode OPNet Modeler

来源： cnki会议评论

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science china(Physics,Mechanics & Astronomy) 2010年第4期53卷 672-679页

作者： MA Jun 1,2, TANG Jun 2 , ZHANG AiHua 3 & JIA Ya 2 1 Department of Physics, Lanzhou university of technology, Lanzhou 730050, china 2 Department of Physics, Central china Normal university, Wuhan 430079, china 3 college of Electrical and information Engineering, Lanzhou university of technology, Lanzhou 730050, china Department of Physics Lanzhou University of Technology Lanzhou 730050 China

The robustness and breakup of spiral wave in a two-dimensional lattice networks of neurons are investigated. The effect of small- world type connection is often simplified with local regular connection and the long-range connection with certain probability. The network effect on the development of spiral wave can be better described by local regular connection and changeable long-range connection probability than fixed long-range connection probability because the long-range probability could be changeable in realistic biological system. The effect from the changeable probability for long-range connection is simplified by multiplicative noise. At first, a stable rotating spiral wave is developed by using appropriate initial values, parameters and no-flux boundary conditions, and then the effect of networks is investigated. Extensive numerical studies show that spiral wave keeps its alive and robust when the intensity of multiplicative noise is below a certain threshold, otherwise, the breakup of spiral wave occurs. A statistical factor of synchronization in two-dimensional array is defined to study the phase transition of spiral wave by checking the membrane potentials of all neurons corresponding to the critical parameters(the intensity of noise or forcing current)in the curve for factor of synchronization. The Hindmarsh-Rose model is investigated, the Hodgkin-Huxley neuron model in the presence of the channel noise is also studied to check the model independence of our conclusions. And it is found that breakup of spiral wave is easier to be induced by the multiplicative noise in presence of channel noise.

关键词： spiral wave factor of synchronization breakup multiplicative noise robustness

维普期刊数据库

The Detection of Defects in Optical Fibers Using a Hybrid Opto-electronic Correlator

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Chinese Journal of Lasers 2000年第3期9卷 15-21页

作者： LIU Yange LIU Wei ZHANG Yimo ZHOU Ge (college of Precision Instrument and Opto-electronics Engineering, Tianjin university Opto-electronic information science and technology Lab., Tianjin 300072, china) 天津大学光电信息技术科学开放实验室天津

A hybrid opto-electronic correlator for detecting defects i n optical fibers is proposed. After the light from a He-Ne laser being expanded and filtered it is not collimated but directly passes a Fourier transform lens and illuminates a reference fiber and a test fiber at the same input plane. The Fourier transform spectrum of the two fibers is therefore obtained at the rear focal plane of the lens, where it is sampled via a CCD array connected with a computer through a frame grabber. The computer performs filter, inverse Fourier transform and setting threshold operation on classification. The system is an equivalent of joint transform correlator with a Fourier lens of long focal length. The experiment results for optical fibers having incoordinate defects are presented. The results indicate that the system can be used for fiber defect detection, and has the advantages of high identification, compact configuration, easy adjustment and flexible manipulation.

关键词： joint transform correlation Fourier transform optical fiber defect detection

RBF neural network and active circles based algorithm for contours extraction

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Progress in Natural science:Materials International 2007年第6期17卷 681-686页

作者： Zhou Zhiheng, Zeng Delu and Xie Shengli(college of Electronic & information Engineering, South china university of technology, Guangzhou 510640, china) college of Electronic & information Engineering South China University of Technology Guangzhou 510640 China

For the contours extraction from the images, active contour model and self-organizing map based approach are popular nowadays. But they are still confronted with the problems that the optimization of energy function will trap in local minimums and the contour evolutions greatly depend on the initial contour selection. Addressing to these problems, a contours extraction algorithm based on RBF neural network is proposed here. A series of circles with adaptive radius and center is firstly used to search image feature points that are scattered enough. After the feature points are clustered, a group of radial basis functions are constructed. Using the pixels’ intensities and gradients as the input vector, the final object contour can be obtained by the predicting ability of the neural network. The RBF neural network based algorithm is tested on three kinds of images, such as changing topology, complicated background, and blurring or noisy boundary. Simulation results show that the proposed algorithm performs contours extraction greatly.

关键词： contours extraction RBF neural network dynamic clustering.

Molecular cloning,characterization and expression analysis of Sox9a and Foxl2 genes in half-smooth tongue sole(Cynoglossussemilaevis)

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Acta Oceanologica Sinica 2011年第1期30卷 68-77页

作者： DONG Xiaoli CHEN Songlin JI Xiangshan SHAO Changwei college of Fisheries Ocean University of China Qingdao 266003 China Key Laboratory for Sustainable Utilization of Marine Fisheries Resources of Ministry ofAgriculture Yellow Sea Fisheries Research Institute Chinese Academy of Fishery SciencesQingdao 266071 China college of Animal science and technology Shandong Agricultural University Taian 271018 China

Two transcription factors, Sox9a and Foxl2 were cloned from half-smooth tongue sole （Cynoglossus semilaevis）. Sox9a is a new duplication of *** Sox9 gene. The complete cDNA of Sox9a gene was 1 842 bp long coding for 487 amino acids and Foxl2 gene was 1 817 bp coding for 308 amino acids. Sox9a was expressed higher in male brain, pituitary and gonad and Foxl2 were higher in female brain, pituitary and gonad. The expression of Sox9a gene in gonads of neo-males was higher than that of normal females. Sox9a and Foxl2 were expressed higher in gastrula stage than in other stages. In the period of sex differentiation, the expression of Sox9a was first going up and then going down and Foxl2 was higher expressed at 37 dph. The highest expressions of Sox9a and Foxl2 genes occurred in nine-month and 12-month old gonad tissues, respectively. Sox9a gene was considered to have inevitable links with sex reversal, sex differentiation and cell differentiation of embryos and formation of spermatogenic ceils. Foxl2 was considered to play a role in sex differentiation, cell differentiation of embryos but not to be necessary for sex determination and sex reversal.

关键词： half-smooth tongue sole Cynoglossus semilaevis Sox9 Foxl2 real-time PCR sexreversal neo-male

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A new algorithm for degree-constrained minimum spanning tree based on the reduction technique

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Progress in Natural science:Materials International 2008年第4期18卷 495-499页

作者： Aibing Ning a, Liang Ma a, Xiaohua Xiong b a School of Management, university of Shanghai for science and technology, Shanghai 200093, china b college of Computer and information, Shanghai Second Polytechnic university, Shanghai 201209, china School of Management University of Shanghai for Science and Technology Shanghai 200093 China college of Computer and information Shanghai Second Polytechnic University Shanghai 201209 China

The degree-constrained minimum spanning tree (DCMST) is an NP-hard problem in graph theory. It consists of finding a spanning tree whose vertices should not exceed some given maximum degrees and whose total edge length is minimal. In this paper, novel math- ematical properties for DCMST are indicated which lead to a new reduction algorithm that can significantly reduce the size of the prob- lem. Also an algorithm for DCMST to solve the smaller problem is presented which has been preprocessed by reduction algorithm.

关键词： Degree-constrained minimum spanning tree Reduction algorithm Edge exchange technique Combinatorial optimization

A centrality measure based on spectral optimization of modularity density

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science china(information sciences) 2010年第9期53卷 1727-1737页

作者： FU LiDong1,2*,GAO Lin1 & MA XiaoKe1 1School of Computer science and Engineering,Xidian university,Xi'an 710071,china 2college of Computer,Xi'an university of science and technology,Xi'an 710054,china School of Computer science and Engineering Xidian University college of Computer Xi"an University of Science and Technology

Centrality analysis has been shown to be a valuable method for the structural analysis of complex *** is used to identify key elements within networks and to rank network elements such that experiments can be tailored to interesting *** this paper,we show that the optimization process of modularity density can be written in terms of the eigenspectrum of kernel *** on the eigenvectors belonging to the largest eigenvalue of kernel matrix,we present a new centrality measure that characterizes the contribution of each node to its assigned community in a network,called modularity density *** measure is illustrated and compared with the standard centrality measures by using respectively an artificial example and a classic network data *** statistical distribution of modularity density centrality is investigated by considering large computer generated graphs and two large networks from the real *** results show the significance of the proposed approach.

关键词： centrality modularity density centrality kernel matrix eigenspectrum

Vector bundle constraint for particle swarm optimization and its application to active contour modeling

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Progress in Natural science:Materials International 2007年第10期17卷 1220-1225页

作者： Zeng Delu, Zhou Zhiheng and Xie Shengli(college of Electronic and information Engineering, South china university of technology, Guangzhou 510641, china) college of Electronic and information Engineering South China University of Technology Guangzhou 510641 China

Active contour modeling (ACM) has been shown to be a powerful method in object boundary extraction. In this paper, a new ACM based on vector bundle constraint for particle swarm optimization (VBCPSO-ACM) is proposed. Different from the traditional particle swarm optimization (PSO), in the process of velocity update, a vector bundle is predefined for each particle and velocity update of the particle is restricted to its bundle. Applying this idea to ACM, control points on the contour are treated as particles in PSO and the evolution of the contour is driven by the particles. Meanwhile, global searching is shifted to local searching in ACM by decreasing the number of neighbors and inertia. In addition, the addition and deletion of particles on the active contour make this new model possible for representing the real boundaries more precisely. The proposed VBCPSO-ACM can avoid self-intersection during contour evolving and also extract inhomogeneous boundaries. The simulation results proved its great performance in performing contour extraction.

关键词： boundary extraction active contour modeling particle swarm optimization velocity update vector bundle.