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Stochastic bi-resonance induced by external noise for Ca^2+ signaling in hepatocytes

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science china Chemistry 2005年第4期48卷 286-291页

作者： ZHANG Jiqian1,2,HOU Zhonghuai1 & XIN Houwen1 1.Department of Chemical Physics,university of science and technology of china,{4. 230026,china 2.college of Physics and Electronic Information,anhui Normal university,Wuhu 24.000,china 1. Department of Chemical Physics University of Science and Technology of China 230026 Hefei China 2. college of Physics and Electronic Information Anhui Normal University 241000 Wuhu China

The influence of external noise on intracellular Ca2+ oscillations dynamics in a single cell of rat hepatocytes is *** coherence of noise-induced intracellular Ca2+ oscillations reached two maxima for multiple external noise intensity,indicating the occurrence of external noise stochastic bi-resonance (SBR).This phenomenon is compared with our previous result that was induced by internal ***,the deterministic bifurcation character of the system was also discussed.

关键词： stochastic bi-resonance, environment fluctuation, calcium oscillations.

Effect of hormonal status and metabolic changes of restricted ewes during late pregnancy on their fetal growth and development

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science china(Life sciences) 2007年第6期50卷 766-772页

作者： GAO Feng1, HOU XianZhi1 & LIU YingChun2 1 college of animal science and animal Medicine, Inner Mongolia {4. university, Huhhot 010018, china 2 college of Biotechnology and Bioengineering, Inner Mongolia {4. university, Huhhot 010018, china 1. college of animal science and animal Medicine Inner Mongolia Agricultural University Huhhot 010018 China 2. college of Biotechnology and Bioengineering Inner Mongolia Agricultural University Huhhot 010018 China

This study investigated the effects of hormonal status; metabolic changes of restricted ewes during late pregnancy on the ovine fetus growth; development. One hundred Mongolian ewes, synchronized for oestrus; mated, were divided into three groups; offered 0.175 MJME·kgw[0.75]·d[1] (Restricted Group 1, RG1), 0.33 MJME·kgw[0.75]·d[1] (Restricted Group 2, RG2); ad libitum access to feed (Control Group, CG) during their late pregnancy respectively. The results suggested that with the supply of exogenous energy decreasing during late pregnancy, maternal body weight; net body weight loss in RG2; RG1 were lower than those of CG (Ps0.01). The insulin; IGF-1 concentrations of ewes in RG2; RG1 tended to be lower than those of CG (P>0.05), but the GH concentrations in RG2; RG1 were enhanced; there was significant difference between RG1; CG on d 120 of gestation (P0.05). However, the NEFA; FAA concentrations of ewes in RG1 were reduced from d 90 to d 120 of gestation, then enhanced from d 120 to d 14. of gestation. During the late pregnancy, with the supply of nutrition decreasing, the negatively physiological; biochemical maternal reactions to restriction became worse, which significantly reduced the average lamb birth weight; daily growth rate of fetus in RG2 (P<0.05); RG1 (P<0.01).

关键词： late pregnancy restricted ewes fetus growth development

s-ordering operator expansions of quantum-mechanical fundamental representations and their applications

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science china(Physics,Mechanics & Astronomy) 2011年第12期54卷 2150-2154页

作者： FAN HongYi 1,3 , XU YeJun 2 & YUAN HongChun 3,4.1 Department of Materials science and Engineering, university of science and technology of{4., hefei 230026,{4. 2 Department of Physics Electronic and Engineering, Chizhou university, Chizhou 24.000,{4. 3 Department of Physics, Shanghai Jiao Tong university, Shanghai 200030,{4. 4.college of Optoelectronic Engineering, Changzhou Institute of technology, Changzhou 213002,{4. 1. Department of Materials science and Engineering University of Science and Technology of China Hefei 230026 China3. Department of Physics Shanghai Jiao Tong University Shanghai 200030 China2. Department of Physics Electronic and Engineering Chizhou University Chizhou 247000 China4. College of Optoelectronic Engineering Changzhou Institute of Technology Changzhou 213002 China

We show that the quantum-mechanical fundamental representations, say, the coordinate representation, the coherent state representation, the Fan-Klauder entangled state representation can be recast into s-ordering operator expansion, which is elegant in form and has many applications in deriving new operator identities. This demonstrates that Dirac's symbolic method can be merged into Newton-Leibniz integration theory in a broad way.

关键词： s-ordering operator expansion operator identities quantum mechanical representation

Asymptotic normality and strong consistency of maximum quasi-likelihood estimates in generalized linear models

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science china Mathematics 2006年第2期49卷 145-157页

作者： YIN Changming, ZHAO Lincheng & WEI Chengdong School of Mathematics and Information science, Guangxi university, Manning 530004. china Department of Statistics and Finance, university of science and technology of china, hefei 230026, china Department of Mathematics, Guangxi Teacher college, Manning 530001, china 1. School of Mathematics and Information science Guangxi University Nanning 530004 China 2. Department of Statistics and Finance University of Science and Technology of China Hefei 230026 China 3. Department of Mathematics Guangxi Teacher College Nanning 530001 China

In a generalized linear model with q x 1 responses, the bounded and fixed (or adaptive) p × q regressors Zi and the general link function, under the most general assumption on the minimum eigenvalue of ZiZ'i,the moment condition on responses as weak as possible and the other mild regular conditions, we prove that the maximum quasi-likelihood estimates for the regression parameter vector are asymptotically normal and strongly consistent.

关键词： generalized linear models quasi-likelihood estimates asymptotic normality strong consistency.

Boundary conditions for the bending of a piezoelectric beam

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science china(Physics,Mechanics & Astronomy) 2008年第7期51卷 847-856页

作者： GAO Yang1, XU SiPeng2 & ZHAO BaoSheng3 1 college of science, china agricultural {4., Beijing 100083, china 2 college of Engineering, Ocean {4. of china, Qingdao 266071, china 3 School of Mechanical Engineering, {4. of science and technology Liaoning, Anshan 114.4., china 1. college of science China Agricultural University Beijing 100083 China 2. college of Engineering Ocean University of China Qingdao 266071 China 3. School of Mechanical Engineering University of Science and Technology Liaoning Anshan 114044 China

For beam bending in transversely isotropic piezoelectric media, the reciprocal theorem and the general solution of piezoelasticity are applied in a novel way to obtain the appropriate stress and mixed boundary conditions accurate to all orders for the beam of general edge geometry and loadings. By generalizing the method developed by Gregory and Wan, a set of necessary conditions on the edge-data for the existence of a rapidly decaying solution is established. The prescribed edge-data of the beam must satisfy these conditions in order that they could generate a decaying state within the beam. When stress and mixed conditions are imposed on the beam edge, these decaying state conditions for the case of bending deformation of piezoelectric beam are derived explicitly. They are then used for the correct formulation of boundary conditions for the beam theory solution (or the interior solution). Besides, an analytical solution of elastic beam is formulated to verify validity of our boundary conditions. For the stress data, our boundary conditions coincide with those obtained in conventional forms of beam theories. More importantly, the appropriate boundary conditions with two sets of mixed edge-data are obtained for the first time.

关键词： boundary conditions beam bending piezoelectric media decaying states regular states

Mixed boundary conditions for piezoelectric plates

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science china(Physics,Mechanics & Astronomy) 2009年第5期52卷 755-761页

作者： GAO Yang 1 ,XU SiPeng 2 &ZHAO BaoSheng 3 1college of science,china agricultural {4.,Beijing 100083,china 2college of Engineering,Ocean {4. of china,Qingdao 266071,china 3 School of Mechanical Engineering,{4. of science and technology of Liaoning,Anshan 114.4.,china college of science China Agricultural University Beijing 100083 China college of Engineering Ocean University of China Qingdao 266071 China School of Mechanical Engineering University of Science and Technology of Liaoning Anshan 114044 China

For plate bending and stretching problems in piezoelectric materials,the reciprocal theorem and the general solution of piezoelasticity are applied in a novel way to obtain the appropriate mixed boundary conditions accurate to all order.A decay analysis technique is used to establish necessary conditions that the prescribed data on the edge of the plate must satisfy in order that it should generate a decaying state within the *** the case of axisymmetric bending and stretching of a circular plate,these decaying state conditions are obtained explicitly for the first time when the mixed conditions are imposed on the plate *** are then used for the correct formulation of boundary conditions for the interior solution.

关键词： boundary conditions piezoelectric plates mixed data bending problems stretching problems

Reduction of drosopterin content caused by a 4.-nt insertion in Henna pre-mRNA of Drosophila melanogaster

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science china(Life sciences) 2008年第8期51卷 702-710页

作者： WANG Qin, ZHAO ChunJiang, BAI LiHua, DENG XueMei & WU ChangXin State Key Laboratory of Agrobiotechnology & Key laboratory of animal Genetics and Breeding of the Ministry of Agriculture, college of animal {4. and technology, china agricultural university, Beijing 100193, china 1. State Key Laboratory of Agrobiotechnology & Key laboratory of animal Genetics and Breeding of the Ministry of Agriculture College of Animal Science and Technology China Agricultural University Beijing 100193 China

Phenylalanine hydroxylase is assumed to be a key enzyme in drosopterin metabolism, but direct in vivo evidence to support this hypothesis is still *** the present study, we found a new natural reces-sive purple eye mutant of Drosophila melanogaster, Hnbp, which was a 4.-nt insertion mutant in the second exon of *** insertion resulted in a predicted protein with 15 additional amino acids as compared to the wild-type *** analysis of protein structure showed that the predicted mutant protein probably had two more β-sheets, which may cause instability of two α-helices near the catalytic centre of the enzyme in the Biopterin-Hydroxyl binding *** mutant showed eye color defect with decrease of mRNA level, as well as drosopterin content *** drosopterin defect could be fully rescued by expression of wild type Henna in the Hnbp background by GMR-GAL4.UAS-Henna/UAS-Henna:Hnbp/Hnbp transgenic *** taken together, it can be concluded that the mu-tation in Henna is responsible for drosopterin reduction in mutant Hnbp, which provides key in vivo evidence to support the hypothesis that Henna is involved in drosopterin synthesis.

关键词： Drosophila melanogaster Henna gene drosopterin phenylalanine hydroxylase Hnbp

A Raw Signal Simulator for Bistatic SAR

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Chinese Journal of Aeronautics 2009年第4期22卷 434-443页

作者： Xia Weijie,Zhou Jianjiang college of Information science and technology,Nanjing university of Aeronautics and Astronautics,Nanjing 210016,{4. [a]college of Information science and technology Nanjing University of Aeronautics and Astronautics Nanjing 210016 China

This article proposes a new efficient raw signal simulator for the bistatic synthetic aperture radar （SAR） based on 2D fast Fourier transform （FFT） to deal with cases of both ideal trajectory and trajectory deviation. It begins with analyzing the geometric configuration and the range history of the bistatic SAR in side-looking and squint modes of ideal trajectory as well as trajectory deviation. Then a detailed and mathematical study is conducted on the equivalence relation of bistatic-to-monostatic applications （BTMA） in the case of ideal trajectory and trajectory deviation. Also a set of formulas are derived for the equivalence relation between bistatic SAR and monostatic SAR on some reasonable assumptions. Therefore, the application of the simulation method based on the 2D FFT for the monostatic SAR can be extended to the case of bistatic SAR. Finally, the simulation results prove the validity of this method. By comparing the efficiency of the proposed method with that of the time domain method, it is shown that the former is a few orders of magnitude higher.

关键词： bistatic synthetic aperture radar raw signal simulation fast Fourier transform

Luminosity-peak energy relation in the decay phases of gamma-ray burst pulses

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science china(Physics,Mechanics & Astronomy) 2010年第1期53卷 163-170页

作者： LU RuiJing & LIANG EnWei Physical science & technology college, Guangxi university, Nanning 530004.{4. 1. Physical science & technology college Guangxi University Nanning 530004 China

Using time-resolved spectral data for a sample of 30 pulses in 27 bright GRBs detected with CGRO/BATSE, we investigate the luminosity-peak energy relation (L-E p relation) in the decay phases of these pulses. A tight L-E p relation is found for most of the pulses, but its power law index is various among pulses, which is normally distributed at 1.84.0.60(1σ) for the pulses in our sample, roughly consistent with the L-E p relation within a GRB and the isotropic gamma-ray energy-E p relation among GRBs. The large scatter of the power law index cannot be explained with both the statistical or observational effects and it may be an intrinsic feature, indicating that no universal L-E p relation would be expected among GRBs/pulses. This may strongly weaken the cosmological use of this relation.

关键词： gamma ray bursts observations statistical luminosity-peak energy relation