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Influences of dibutyryl cyclic adenosine monophosphate and forskolin on human sperm motility in vitro

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Asian Journal of Andrology 2003年第2期5卷 113-115页

作者： Ji-Hong LIU, Yang LI, Zheng-Guo CAO, Zhang-Qun YEDepartment of Urology, Tongji Hospital, Tongji Medical college, huazhong University of science and technology,wuhan 430030, china Department of Urology Tongji Hospital Tongji Medical College Huazhong University of Science and Technology Wuhan 430030 China

Aim: To study the influences of dibutyryl cyclic adenosine monophosphate (dbcAMP) and forskolin on human sperm motility in vitro. Methods: Semen samples, aseptically obtained by masturbation and prepared by swim-up technique from 20 fertile men, were incubated with different concentrations of dbcAMP and forskolin at 37 癈. Measurements were carried out after 10 min, 20 min, 30 min and 60 min incubation. Motility parameters were estimated by using an automatic analyzing system. Results: Treatment with dbcAMP or forskolin resulted in a significant increase in sperm motility and progressive motility. The larger the concentrations of dbcAMP or forskolin, the greater the effect appeared. The straight linear velocity and curvilinear velocity were not affected by both agents. Conclusion: dbcAMP and forskolin increase the motility and progressive motility of human sperm in vitro.

关键词： dibutyryl cyclic AMP forskolin sperm motility

A SEMI-ANALYTICAL AND SEMI-NUMERICAL METHOD FOR SOLVING 2-D SOUND-STRUCTURE INTERACTION PROBLEMS

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Acta Mechanica Solida Sinica 2003年第2期16卷 116-126页

作者： Xiang Yu Huang Yuying (college of Civil Engineering and Mechanics,huazhong University of science and technology,wuhan 430074,china) collegeofCivilEngineeringandMechanics HuazhongUniversityofScienceandTechnologyWuhan430074China

Based on the transfer matrix method and the virtual source simulation technique, this paper proposes a novel semi-analytical and semi-numerical method for solving 2-D sound- structure interaction problems under a harmonic *** any integration segment, as long as its length is small enough,along the circumferential curvilinear coordinate,the non- homogeneous matrix differential equation of an elastic ring of complex geometrical shape can be rewritten in terms of the homogeneous one by the method of extended homogeneous capacity proposed in this *** the exterior fluid domain,the multi-circular virtual source simulation technique is *** source density distributed on each virtual circular curve may be ex- panded as the Fourier's *** with the inverse fast Fourier transformation,a higher accuracy and efficiency method for solving 2-D exterior Helmholtz's problems is presented in this *** the aspect of solution to the coupling equations,the state vectors of elastic ring induced by the given harmonic excitation and generalized forces of coefficients of the Fourier series can be obtained respectively by using a high precision integration scheme combined with the method of extended homogeneous capacity put forward in this *** to the superposition princi- ple and compatibility conditions at the interface between the elastic ring and fluid,the algebraic equation of system can be directly constructed by using the least square *** of acoustic radiation from two typical fluid-loaded elastic rings under a harmonic concentrated force are *** results show that the method proposed is more efficient than the mixed FE-BE method in common use.

关键词： sound-structure interaction acoustic radiatlon multi-circular virtual source simulation technique transfer matrix method inverse fast Fourier transformation semi-analytical and semi-numerical method

Evolution of Bright Screening-photovoltaic Spatial Optical Solitons

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Chinese Journal of Lasers 2001年第5期10卷 28-33页

作者： LIU Jinsong (State Key Laboratory of Laser technology, huazhong University of science and technology, wuhan 430074, china) 华中科技大学激光技术国家重点实验室湖北武汉

A numerical analysis of the dynamical evolution of bright screening photovoltaic (SP) spatial solitons in biased photovoltaic photorefractive materials in the case of neglecting the material loss and the diffusion is presented. When an incident optical beam is a bright SP soliton, the beam propagates along a linear path with its shape kept unchanged. When the incident optical beam is slightly different from a bright SP soliton, the beam reshapes itself and tries to evolve into a bright SP soliton after a short distance. However, when the incident optical beam is significantly different from a SP bright soliton, the beam cannot evolve into a stable bright SP soliton, and tends to experience periodic compression and expansion. For a low intensity input beam, the wave experiences a periodic process of compression first and then expansion during the initial part of the cycle. For a high intensity input beam, however, the wave will initially diffract and then experiences compression during the cycle.

关键词： nonlinear optics spatial optical solitons photorefractive effects

Neural Nets:Another Paradigm for Decision Support

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Journal of Systems Engineering and Electronics 1995年第2期6卷 2-8页

作者： Feng Shan (Dept. of ACE, huazhong University of science and technology, wuhan 430074, china) Dept. of ACE Huazhong University of Science and Technology Wuhan 430074 China

The paper presents an important aspect of Neural Nets application, i. e., their usefulness for decision support. The essential feature of the neural net approach to decision making is that it is a black-box approach, which means one does not try to model the underlying processes, but only looks for a tuning of the parameters of the neural net such that the black-box mimics the sensible behavior. Through the existing widespread applications in industry, business and science, the paper emphasizes their common property as a paradigm for decision support.

关键词： Neural network Neural-net controller Decision support Industrial applications.

Effect of amyloid peptides on serum withdrawal-induced cell differentiation and cell viability

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Cell Research 2004年第6期14卷 467-472页

作者： Yi Peng WANG, Ze Fen WANG, Ying Chun ZHANG, Qing TIAN, Jian Zhi WANG Department of Pathophysiology, Tongji Medical college, huazhong University of science and technology, wuhan, 430030, china Department of Pathophyiiology Tongji Medical College Huazhong University of Science and Technology Wuhan 430030 China

Abnormal deposition of amyloid-p(Ap) peptides and formation of neuritic plaques are recognized as pathological processes in Alzheimer’s disease (AD) brain. By using amyloid precursor protein (APP) transfected cells, this study aims to investigate the effect of overproduction of Aβ on cell differentiation and cell viability. It was shown that after serum withdrawal, untransfected cell (N2a/Wt) and vector transfected cells (N2a/vector) extended long and branched cell processes, whereas no neurites was induced in wild type APP (N2a/APP695) and Swedish mutant APP (N2a/ APPswe) transfected N2a cells. After differentiation by serum withdrawal, the localization of APP/AP and neurofilament was extended to neurites, whereas those of APP-transfected cells were stillrestricted within the cell body. Levels of both APP and Aβ were significantly higher in N2a/APP695 and N2a/APPswe than in N2a/Wt, as determined by Western blot and Sandwich ELISA, respectively. To further investigate the effect of A0 on the inhibition

关键词： Alzheimer’s disease amyloid β cell differentiation.

Effects of Carvedilol on Cardiomyocyte Apoptosis and Gene Expression In Vivo after Ischemia-Reperfusion in Rats

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Journal of huazhong University of science and technology(Medical sciences) 2003年第2期23卷 127-130页

作者：曾和松刘晓春赵华月 Department of Cardiology Tongji Hospital Tongji Medical College Huazhong University of Science and Technology Wuhan 430030 Department of Neurobiology Tongji Medical College Huazhong University of Science and Technology Wuhan 430030

The effects of carvedilol on cardiomyocyte apoptosis and expression of bcl-2. bax genes following ischemia (0. 5 h) and reperfusion (48 h) in vivo and the possible biological mechanism of carvedilol inhibiting cardiomyocyte apoptosis were studied. The left anterior descending artery in Wistar rats were ligated to establish ischemia-reperfusion (I/R) models. The model animals were divided into two groups: I/R group, the model rats not subject to other treatments except ischemia-reperfusion (n= 8); carvedilol-treated group (n= 8), I/R model rats treated with carvedilol. Eight rats in the sham-operated group were subjected to only experimental open operation. The number of apoptotic cardiomyocyte was determined by TUNEL staining. Immunohistochemistry and in situ hybridization histochemistry (ISHH) were used to detect the expression of bcl-2 and bax genes. Image processing system was used to quantitatively dispose the positive metric substances of both immuno-histochemistry and ISHH through the average optical density (OD) value. The results showed that the number of the apoptotic cells were 36. 18±9 (I/R group) . 0-1 (sham-operated group) and 9. 5± 3 (carvedilol-treated group) in each visual field respectively with the difference being very significant among the groups (P2 protein in sham-operated group, I/R group and carvedilol-treated group were 0. 14±0. 01, 0. 08±0. 02 and 0. 15±0. 03, respectively. The OD values of bcl-2 mRNA in sham-operated group, I/R group and carvedilol-treated group were 0. 08± 0. 01, 0. 06±0. 01 and 0. 09±0. 01, respectively. There was no significant difference between carvedilol-treated group and I/R group (P>0. 05). The OD values of bax protein in I/R group, sham-operated and carvedilol-treated-treated group were 0. 13±0. 02, 0. 07±0. 01, 0. 06±0. 01, respectively. There was very significant difference between carvedilol-treated group and I/R group (P 2/bax ratio was 1. 07±0. 14 (I/R group), 1. 28

关键词： carvedilol ischemia-reperfusion apoptosis gene expression

ON THE ALMOST SURELY ASYMPTOTIC BOUNDS OF A CLASS OF ORNSTEIN-UHLENBECK PROCESSES IN INFINITE DIMENSIONS

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Journal of Systems science & Complexity 2008年第3期21卷 416-426页

作者： Yuhong LI college of Hydropower and Information Engineering Huazhong University of Science and Technology Wuhan 430074 China

Given a real-valued separable M-type 2 Banach space X with the p-th power of the norm of C2-class, the almost sure asymptotic upper bounds of the solutions of the Ornstein-Uhlenbeck Processes described by the following equations {dz（t）=A（t,z（t））dt＋σ（t,z（t））dW（t）,z（0）=z0∈X,are investigated. This study generalizes the corresponding well-known finite dimensional results of Lapeyre （1989） and Mao （1992）.

关键词： Almost surely asymptotic bounds infinite dimension M-type 2 Banach space Ornstein-Uhlenbeck Processes

Effects of NaNbO_3-Co_2O_3 Co-additive on the Properties of PZN-PZT Ceramics

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Journal of wuhan University of technology(Materials science) 2007年第4期22卷 722-724页

作者：邓毅华 college of Material science and Engineering South China University of Technology Department of Electronic science and technology Huazhong University of Science and TechnologyWuhan 430074China

NaNbO3-Co2O3 co-added PZN-PZT （PZCNNT） ceramics were prepared using conventional solid state reaction. The piezoelectric and dielectric properties were measured. The experimental results show that the addition of 0.3mo1% Co2O3 leads to low dielectric loss （tgδ） in PZCNNT ceramics and the proper addition of NaNbO3 not only improves piezoelectric properties but also decreases intensively dielectric loss and mechanical loss. The optimal ceramic having d33=310 pC/N, kp=0.59, εr=985, tgδ=0.0034, Qm=1380 was obtained.

关键词： PZN-PZT piezoelectric constant dielectric constant dielectric loss

DYNAMIC SIMULATION OF ROTATING SHELLS COUPLED WITH LIQUID

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Acta Mechanica Solida Sinica 2001年第2期14卷 169-175页

作者： Wei Fayuan Li Shiqi Huang Yuying~1 Zhong Yifang (college of Mechanical science and Engineering, huazhong University of science and technology, wuhan 430074, china) (1 Department of Mechanics, huazhong University of science and technology, wuhan 430074,china) ***

The dynamic behaviors of rotating shells coupled with liquid areshown. The shell under con- sideration has arbitrary boundaryconditions and a complex shape. A modified boundary element methodand finite strip technique are used to improve the computingefficiency and to guarantee the continuity conditions on theliquid-shell interaction plane. The effects of various parameterssuch as shell's thickness and liquid depth are investigated. Dynamicsimulations are applied to several typical shell-liquid systems, andthe natu- ral frequencies, mode shapes and response of vibration arecalculated numerically.

关键词： rotting shells dynamic simulation fluid-solid interaction