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A novel model-free approach for reconstruction of time-delayed gene regulatory networks

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中国科学：生命科学英文版 2006年第2期49卷 190-200页

作者： JIANG Wei1,2. LI Xia1,2.3.4, GUO Zheng1,2.3. LI Chuanxing1, WANG Lihong1 & RAO Shaoqi1,5 1. Department of Bioinformatics, Harbin Medical {2., Harbin 150086, China 2. Department of Computer Science, Harbin institute of {2., Harbin 150080, China 3. School of Life Science and {2., Tongji {2., Shanghai 2.0092. China 4. biomedical Engineering institute, Capital {2. of Medical Sciences, Beijing 100054, China 5. Departments of Cardiovascular Medicine and Molecular Cardiology, Cleveland Clinic Foundation, Cleveland, Ohio 44195, USA Department of Bioinformatics Harbin Medical University Harbin China Department of Computer Science Harbin Institute of Technology Harbin China School of Life Science and technology Tongji University Shanghai China Departments of Cardiovascular Medicine and Molecular Cardiology Cleveland Clinic Foundation Cleveland USA

Reconstruction of genetic networks is one of the key scientific challenges in functional genomics. This paper describes a novel approach for addressing the regulatory dependencies be-tween genes whose activities can be delayed by multiple units of time. The aim of the proposed ap-proach termed TdGRN (time-delayed gene regulatory networking) is to reversely engineer the dy-namic mechanisms of gene regulations, which is realized by identifying the time-delayed gene regu-lations through supervised decision-tree analysis of the newly designed time-delayed gene expres-sion matrix, derived from the original time-series microarray data. A permutation technique is used to determine the statistical classification threshold of a tree, from which a gene regulatory rule(s) is ex-tracted. The proposed TdGRN is a model-free approach that attempts to learn the underlying regula-tory rules without relying on any model assumptions. Compared with model-based approaches, it has several significant advantages: it requires neither any arbitrary threshold for discretization of gene transcriptional values nor the definition of the number of regulators (k). We have applied this novel method to the publicly available data for budding yeast cell cycling. The numerical results demonstrate that most of the identified time-delayed gene regulations have current biological knowledge supports.

关键词： gene regulatory networks, time delayed, decision tree.

Fabrication of sub-micro size PZT array and their ferroelectric properties

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Science China(Technological Sciences) 2006年第6期49卷 693-700页

作者： ZHAO Gaoyang1, ZHANG Weihua1, XU Guomin1, DENG Xiaocui1, JIANG Bailing1 & ZHAO Wei2.1. School of Materials Science and Engineering, Xi’an university of technology, Xi’an 710048, China 2. Xi’an {2. of Optics and Precision {3. of CAS, Xi’an 710048, China School of Materials Science and Engineering Xi’an University of Technology Xi’an China Xi’an institute of Optics and Precision mechanics of CAS Xi’an China

The photosensitive PZT sols and their gel films were prepared by sol-gel process. Based on the photosensitivity of the PZT gel films, two-dimensional (2.) array of the PZT gel film was fabricated using twice-exposure of double-beam interference on the gel film. PZT gel films coated on ITO/quartz substrate were exposed to an interference fringe of 3.5 He-Cd laser beams, the substrate was rotated by 90° between the first and second irradiation steps. Island type periodic 2. array structures with a pitch of 1 μm and cell size of about 480 nm × 480 nm × 40 nm were formed after the irradiation, and followed by leaching with organic solvent, and then by heat treatment at 600°C for 15 min. The hysteresis loops of the cell in PZT array were in-situ measured by the online-operation of TF analyzer and atomic force microscope (AFM). The probe can be located on the locked cell of PZT array in the AFM image. The alternating voltage applied to the locked cell is supplied by the TF analyzer through the conductive coating probe, and then the test signal is fed back to the TF analyzer to obtain the hysteresis loop of the locked cell of array in the absence of top electrode. The results show that the sub-micro size PZT arrays prepared in this way are of polarization reversal characteristics with the alternating electric fields, thereby exhibiting obvious ferroelectricity.

关键词： PZT, ferroelectric films, photosensitivity, hysteresis loop.

Computer Simulation of the Indentation Creep Tests on Particle-Reinforced Composites

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Journal of Materials Science & technology 2002年第4期18卷 335-340页

作者： Zhufeng YUE1,2.1)Department of Engineering mechanics, Northwestern Polytechnical university, Xi’an 710072. China{2. of Materials, Ruhr university, 44780 Bochum, Germany Dept. of Eng. Mech. Northwestern Polytech. Univ. Xi'an 710072 China Inst. of Mat. Ruhr Univ. 44780 Bochum Germany

A systematical simulation has been carried out on the indentation creep test on particle-reinforced composites. The deformation, failure mechanisms and life are analyzed by three reasonable models. The following five factors have been considered simultaneously: creep property of the particle, creep property of the matrix, the shape of the particle, the volume fraction of the particle and the size (relative size to the particle) of the indentation indenter. For all the cases, the power law respecting to the applied stress can be used to model the steady indentation creep depth rate of the indenter, and the detail expressions have been presented. The computer simulation precision is analyzed by the two-phase model and the three-phase model. Two places of the stress concentration are found in the composites. One is ahead of the indentation indenter, where the high stress state is deduced by the edge of the indenter and will decrease rapidly near to a steady value with the creep time. The other one is at the interface, where the high stress state is deduced by the misfit of material properties between the particles and matrix. It has been found that the creep dissipation energy density other than a stress parameter can be used to be the criterion to model the debonding of the interfaces. With the criterion of the critical creep dissipation energy density, a power law to the applied stress with negative exponent can be used to model the failure life deduced by the debonding of interfaces. The influences of the shape of the particles and the matching of creep properties of particle and matrix can be discussed for the failure. With a crack model, the further growth of interface crack is analyzed, and some important experimental phenomena can be predicted. The failure mechanism which the particle will be punched into matrix has been also discussed. The critical differences between the creep properties of the particles and matrix have been calculated, after a parameter has b

关键词： Indentation creep test Particle-reinforced composites Computer simulation Deformation Failure

Comparison of energy structure and spectral properties of Ce:LaAlO_3.and Ce:Lu_2.SiO_4)O

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Science China(Technological Sciences) 2009年第12期52卷 3678-3682页

作者： WANG XiaoDan 1 ,PAN Tao 1 ,ZANG TaoCheng 1 ,LI JianKang 1 ,ZHAO ZhiWei 2.,ZHANG LianHan 2.&XU Jun3.1Department of applied Physics,{2. of Science and {2. of Suzhou,Suzhou 2.5009,China 2.hanghai {3. of Optics and Fine mechanics,Chinese Academy of Sciences,Shanghai 2.1800,China 3.hanghai {3. of Ceramics,Chinese Academy of Sciences,Shanghai 2.1800,China Department of applied Physics University of Science and Technology of Suzhou Suzhou China Shanghai institute of Optics and Fine mechanics Chinese Academy of Sciences Shanghai China Shanghai institute of Ceramics Chinese Academy of Sciences Shanghai China

Undoped LaAlO3.and 1 at.%Ce:LaAlO3.single crystals were grown by the Czochralski *** and fluorescence spectra were measured at room *** energy levels structure of Ce:LaAlO3.was *** this paper,two viewpoints were *** first one is:the energy levels structure of Ce:LaAlO3.is very similar to that of Ce:Lu2.SiO4)O which is a well-known *** the energy levels structure of Ce:LaAlO3.and Ce:Lu2.SiO4)O,the lowest 5d energy level of Ce 3. is located below the bottom of the conduction band of host crystal and the other higher 5d energy levels of Ce 3. are located above the bottom of the conduction band of host *** second one is:Ce:LaAlO3.single crystal may not be suitable for scintillation application;by comparing the energy levels structures of Ce:LaAlO3.and Ce:Lu2.SiO4)O,the large energy difference(1.13.eV)between the two lowest 5d energy levels of Ce 3. in LaAlO3.is a crucial factor that causes the luminescence quenching.

关键词： Ce:LaAlO3 Ce:Lu2.SiO4)O energy-level absorption luminescence

Osteoarthritis and age-related changes in viscoelastic properties of articular chondrocytes in experimental rabbit model

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Osteoarthritis and age-related changes in viscoelastic prope...

X-ray spectra induced in highly charged 40Ar^q+ interacting with Au surface

2.08年全国生物流变学与生物力学学术会议

作者： ZHANG Quan-you,CHEN Wei-yi(institute of applied {2. and {3. Engineering,taiyuan university of technology,taiyuan,03.02.,China)

Articular cartilage is a relatively uncomplicated and dynamic tissue composed of *** cartilage is avascular, alymphatic,and aneural,chondrocyte activity is believed to be regulated predominantly by local factors in the cellular microenvironment,including soluble mediators,matrix composition,and biophysical factors such as mechanical *** proposed autologous chondrocyte implantation require that autologous articular chondrocytes are isolated from a patient’s own cartilage,expanded in vitro,and reimplanted into a full - thickness articular surface defect or used to engineer implantable ***,some aspects challenge the use and clinical outcome of cartilage repair *** to now,there are well described cellular changes associated with osteoarthritis and aging in the synthetic and metabolic activity,growth factor responsiveness and proliferation rates of ***,the most important aspect is whether the viscoelastic properties of chondrocytes obtained from autologous cartilage with different OA degree and age is identical.

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Science China(Physics,mechanics & Astronomy) 2006年第2期49卷 203-212页

作者： ZHANG Xiao’an1,2. XIAO Guoqing1, YANG Zhihu1, CHEN Ximeng3. ZHAO Yongtao1, LI Fuli4, ZHANG Yinping1, CUI Ying3. ZHANG Hongqiang3. XU Xu3. SHAO Jianxiong3.& ZHAN Wenlong11. institute of Modern Physics, Chinese Academy of Sciences, Lanzhou 73.000, China 2. Department of Physics, Xianyang Normal university, Xianyang 712.00, China 3. Department of Modern Physics, Lanzhou university, Lanzhou 73.000, China 4. Department of {3. Physics, Xi’an Jiaotong university, Xi’an 710049, China institute of Modern Physics Chinese Academy of Sciences Lanzhou China Department of Physics Xianyang Normal University Xianyang China Department of Modern Physics Lanzhou University Lanzhou China Department of applied Physics Xi’an Jiaotong University Xi’an China

By use of optical spectrum technology, the spectra of X-ray induced by highly charged 40Arq+ ions interacting with Au surface have been studied. The results show that the argon Kα X-ray were emitted from the hollow atoms formed below the surface. There is a process of multi-electron exciting in neutralization of the Ar16+ion, with electronic con-figuration 1s2.in its ground state below the solid surface. The yield of the projectile Kα X-ray is related to its initial electronic configuration, and the yield of the target X-ray is related to the projectile kinetic energy.

关键词： highly charged ion hollow multi-electron excitation X- ray.

Nonlinear flexural wave equation and exact traveling solutions in beams

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Nonlinear flexural wave equation and exact traveling solutio...

Spinning Deformation Criteria of Thin-walled Tubular Part with Longitudinal Inner Ribs

第五届国际非线性力学会议

作者： Zhi-fang Liu~1,Tie-feng Wang~2.Shan-yuan Zhang~1 (1.institute of applied {2.,{3.,taiyuan 03.02.,China 2.College of Civil and Environmental Engineering,{3., taiyuan 03.02.,China)

＜正＞A nonlinear flexural wave equation of the beam taking account of large deflection and geometric dispersion was derived by means of the Hamilton *** results of qualitative analysis of the nonlinear evolution show that the equation has homoclinic or heteroclinic orbits on the phase plane,which corresponds to solitary wave or shock wave solution,*** flexural wave equation was solved by using the Jacobi elliptic function expansion *** kinds of exact periodic solutions of the nonlinear equations are obtained,including the shock wave solution and the solitary wave *** necessary condition for the existence of these solutions was discussed,which is consistent with the qualitative *** nonlinear Schr（o|¨）dinger equation was derived from the nonlinear flexural wave equation.

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Journal of Wuhan university of technology(Materials Science) 2006年第4期21卷 169-172页

作者：江树勇 Engineering Training Center Harbin Engineering University Harbin 150001China

As a successive and local plastic deformation process, backward ball spinning was applied for the purpose of prodacing thin-walled tubular parts with longitudinal inner ribs. According to the local plastic deformation theoo,, the application of yield criterion to the spinning process and the influence of the radial spinning force component on the formability of inner ribs were analyzed. Based on yield criterion and plastic mechanics, the stable flow rule of metal material and forming criteria of the inner ribs were obtained aad conformed to the experimental results so as to contribute greatly to improving the ball spinning process and optimizing the process variables, such as the diameter of ball, the reduction in a pass and the wall thickness of tubular blank, which have a significant influenee on the formability of the inner ribs. The knowledge of the influence of the process variables such as the diameter of ball, the reduction in a pass and the wall thickness of tubular blank on the spinning process is essential to preventing the quality defects of the spun parts and obtaining the desired spun parts.

关键词： ball spinning power spinning spinning force criterion

Numerical study on scanning radiation acoustic field in formations generated from a borehole

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Science China(Physics,mechanics & Astronomy) 2005年第2期48卷 247-256页

作者： CHE Xiaohua1, ZHANG Hailan1, QIAO Wenxiao2.& JU Xiaodong2.1. institute of Acoustics, Chinese Academy of Sciences, Beijing 100080, China 2. Faculty of Natural Resources & Information technology, {2. of Petroleum, Beijing 102.49, China institute of Acoustics Chinese Academy of Sciences Beijing China Faculty of Natural Resources & Information technology University of Petroleum Beijing China

Numerical study on scanning radiation acoustic field in formations generated by linear phased array transmitters in a fluid-filled borehole is carried out using a real axis integration (RAI) method. The main lobe width of the acoustic beams and the incident angle on the borehole wall can be controlled by means of adjusting parameters, such as the element number and the delay time between the neighboring array elements of linear phased array transmitter. The steered angle of longitudinal waves generated in the formation satisfies the Snell’s law for plane waves when the incident angle on the borehole wall is less than the first critical angle. When the lobe width of the acoustic beams is narrow and the steered angle is less than the first critical angle, the acoustic field in the formation can be approximately calculated given that the linear phased array is put in the formation without borehole. The technique of scanning radiation acoustic field can be applied to enhancing investigation resolution and signal-to-noise ratio in crosswell seismic survey and borehole acoustic reflection imaging.

关键词： formation, linear phased array transmitter, steered angle, RAI, scanning radiation.