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Journal of Computational Mathematics 2001年第6期19卷 591-600页

作者： Dong-sheng Wu (institute of Systems science, academy of Mathematics and Systems sciences, chinese academy of sciences, beijing 100080, China ) 中科院系统科学所北京 100080

Presents a probabilistic numerical approach for a class of probabilistic differential equation. Application of the Brownian motion and Monte-Carlo method; Application in the valuation of European Options.

关键词： Brownian motion probabilistic numerical solution European Options

CONVERGENCE AND SUPERCONVERGENCE OF HERMITE BICUBIC ELEMENT FOR EIGENVALUE PROBLEM OF THE BIHARMONIC EQUATION

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Journal of Computational Mathematics 2001年第2期19卷 139-142页

作者： Dong-sheng Wu (institute of Systems science, academy of Mathematics and Systems sciences, chinese academy of sciences, beijing 100080, China ) 中科院系统科学所北京 100080

Provides information on a study which discussed the convergence and superconvergence for eigenvalue problem of the biharmonic equation using the Hermite bicubic element. Discussion on eigenvalue problem for biharmonic equation; Background on asymptotic error expansions and interpolation postprocessing; Superconvergence approximations to the eigenvalue and eigenfunction.

关键词： Hermite bicubic element biharmonic equation interpolation postprocessing eigenvalue problem

SYNTHESIS AND CHARACTERIZATION OF NEW STABILIZERS WITH OPTIMAL MOLECULAR WEIGHT

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chinese Journal of Polymer science 2001年第4期19卷 341-350页

作者： Jiang-qing Pan institute of Chemistry chinese academy of sciences, beijing 100080 China 中科院化学所北京

Over 2 x 10(8) tons of polymers are produced every year, and a large portion of polymers faces the degradation problem. There are many effective methods to protect polymers against degradation and the addition of stabilizers to polymer remains the most convenient and effective way of enhancing polymer life and performance. In this article, a series of effective stabilizers with optimal molecular weight (MW), including common, monomeric and polymeric stabilizers (antioxidant and light stabilizer) were synthesized using isocyanation, controlled isocyanation, hydrosilylation, epoxide addition, macroreaction of stabilizing functional compounds and polymerization of monomeric stabilizers. The structure and performance of these new stabilizers were characterized by using IR, NMR, MS, UV-spectra, XPS and elemental analysis. The current development of stabilizer synthesis was also reviewed.

关键词： preparation of stabilizer antioxidant hindered amine light stabilizer isocyanation hydrosilylation

Reduction of choline acetyltransferase activities in APP770 transgenic mice

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chinese science Bulletin 2000年第9期45卷 834-838页

作者： LI Huiinstitute of zoology, chinese academy of sciences, beijing 100080, China institute of zoology Chinese Academy of Sciences Beijing China

Transgenic mice overexpressing the 770-amino acid isoform of human Alzheimeramyloid precursor protein exhibit extracellular β-amyloid deposits in brain regions including cerebral cortex and hippocampus, which are severely affected in Alzheimer’s disease patients. Significant reduction in choline acetyltransferase (ChAT) activities has been observed in both cortical and hippocampal brain regions in the transgenic mice at the age of 10 months compared with the age-matched non-transgenic mice, but such changes have not been observed in any brain regions of the transgenic mice under the age of 5 months. These results suggest that deposition of β-amyloid can induce changes in the brain cholinergic system of the transgenic mice.

关键词： Alzheimer’s disease β-amyloid cholinergic transgenic.

Role of plasminogen activators and inhibitors in reproduction

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chinese science Bulletin 1999年第8期44卷 673-685页

作者： LIU YixunState Key Laboratory of Reproductive Biology, institute of zoology , chinese academy of sciences , beijing 100080, China State Key Laboratory of Reproductive Biology Institute of Zoology Chinese Academy of Sciences Beijing China

The recent progress in the studies on the role of local and directed fibrinolysis controlled by plasminogen activators (PAs) and regulated by their inhibitors (PAIs) in reproduction is summarized. Hormone-induced coordinated expression of tissue type PA (tPA) and PAI type-1 (PAI-1) in the ovary is involved in the processes of ovulation and luteal regression; increases in urokinase type PA (uPA) and PAI-1 activity in the early stage of luteinized follicles may be responsible for ovarian tissue remodeling and angiogenesis; the PA system has been found to play an important role in spermatogenesis in testis and modulation of sperm maturation in epididymis. PA and matrix matalloproteanase (MMP) and their respective inhibitors have also been identified in trophoblast and uterus. The targeted proteolytic activity generated by the two systems may play an essential role in the processes of the cyclic uterine angiogenesis, implantation and pla-centation as well as parturition.

关键词： plasminogen activator and inhibitor follicle rupture luteolysis angiogenesis spermatogenesis placentation.

Review on the study of entanglement in quantum computation speedup

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chinese science Bulletin 2007年第16期52卷 2161-2166页

作者： DING ShengChao1,3 & JIN Zhi1,2,1 institute of Computing Technology,chinese academy of sciences,beijing 100080,China 2 academy of Mathematics and Systems science,chinese academy of sciences,beijing 100080,China 3 Graduate University of chinese academy of sciences,beijing 100080,China institute of Computing Technology Chinese Academy of Sciences Beijing 100080 China Graduate University of chinese academy of sciences Beijing 100080 China academy of Mathematics and Systems science Chinese Academy of Sciences Beijing 100080 China

The role the quantum entanglement plays in quantum computation speedup has been widely disputed. Some believe that quantum computation's speedup over classical computation is impossible if entan-glement is absent,while others claim that the presence of entanglement is not a necessary condition for some quantum algorithms. This paper discusses this problem systematically. Simulating quantum computation with classical resources is analyzed and entanglement in known algorithms is reviewed. It is concluded that the presence of entanglement is a necessary but not sufficient condition in the pure state or pseudo-pure state quantum computation speedup. The case with the mixed state remains open. Further work on quantum computation will benefit from the presented results.

关键词：量子论量子纠缠量子计算加速模拟

Local canonical correlation coefficients and canonical variables of groups of random variables

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chinese science Bulletin 1998年第10期43卷 815-817页

作者： XU Xingzhong institute of Systems science, chinese academy of sciences, beijing 100080, China institute of Systems science Chinese Academy of Sciences Beijing China

The concepts of local correlation coefficient, local canonical correlation coefficients and local canonical variables of groups of random variables are defined, which generalize the classical concepts in two groups of random *** concepts together with total corresponding concepts clarify the correlativity among groups of random variables.

关键词： groups of random variables covariance matrix local canonical correlation coefficients local canonical variables.

A quasi-local mass for 2-spheres with negative Gauss curvature

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science China Mathematics 2008年第9期51卷 1644-1650页

作者： ZHANG Xiao institute of Mathematics, academy of Mathematics and Systems science, chinese academy of sciences, beijing 100080, China institute of Mathematics Academy of Mathematics and Systems Science Chinese Academy of Sciences Beijing China

We extend our previous definition of quasi-local mass to 2-spheres whose Gauss curvature is negative, and prove its positivity.

关键词： general relativity quasi-local mass positivity 53C27 53C50 83C60

New fossil ommatid (Coleoptera:Archostemata:Ommatidae) from Jehol Biota of western Liaoning, China

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Progress in Natural science:Materials International 2006年第6期16卷 639-643页

作者： REN Dong, TAN Jingjing and GE Siqin (College of Life science, Capital Normal University, beijing 100037, China institute of zoology, chinese academy of sciences, beijing 100080, China) College of Life science Capital Normal University Beijing 100037 China institute of zoology Chinese Academy of Sciences Beijing 100080 China

In this paper one new genus and one new species of fossil ommatid, Odontomma trachylaena gen. et sp. nov., is described and illustrated from the Late Jurassic or Early Cretaceous Yixian Formation of western Liaoning, China. Based on wide epipleural space of elytron with several rows of cells, the new taxa is attributed to tribe Brochocoleini of Ommatidae and compared with genus Bro-chocoleus. Due to the fact that most other chinese Mesozoic ommatids are not complete, the complete preservation of the new specimens reported here enabled us to determine the characteristics of the body of these ancient ommatid. Moreover, based on the well-preserved individual of this new genus, we may suppose the affinities of the new species with extant and extinct groups.

关键词： Ommatidae Late Jurassic Early Cretaceous Liaoning Province.