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Moderate deviation for super-Brownian motion with immigration

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Science china Mathematics 2004年第3期47卷 440-452页

作者： ZHANG Mei Department of Mathematics, beijing normal university, beijing 100875, china Department of Mathematics, The Central university of Finance and Economics, beijing 100081, china Department of Mathematics Beijing Normal University Beijing China Department of Mathematics The Central University of Finance and Economics Beijing China

We prove a moderate deviation principle for a super-Brownian motion with immigration of all dimensions, and consequently fill the gap between the central limit theorem and large deviation principle.

关键词： moderate deviation principle super-Brownian motion with immigration large deviation principle evolution equation

Application of annexation principle to the study of thermodynamic properties of Ag-Bi-In metallic melts

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Journal of university of Science and Technology beijing 2003年第1期10卷 18-20页

作者： Jian ZhangMetallurgy school, university of Science and Technology beijing, beijing 100083, china Metall. Sch. Univ. of Sci. and Technol. Beijing Beijing 100083 China

Based on the measured activities, the phase diagrams and the annexation principle, the calculating models of mass action concentrations for Ag-Bi and Ag-Bi-In melts have been formulated. The calculated results agree with practice and obey the mass action law, showing that the models formulated can reflect the structural characteristics of both melts. Meanwhile, it confirms that annexation principle is applicable to the Ag-Bi-In metallic melts. The melts involving eulectic which give rise to phase separation, and in which activities exhibit positive deviation from Raoult's law is the basic cause of melts transforming from homogeneous to heterogeneous ones.

关键词： the mass action law annexation principle two phase melts activity, mass action concentration

The studies on neurogenesis induced by brain injury inadult ring dove

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Cell Research 1998年第2期8卷 151-158页

作者： ZUO MING XUE(Biology Department, beijing normal university, beijing100875, china) Biology Department Beijing Normal University Beijing China

It was the first time demonstrated by us that the number of newborn neurons was increajsed after making lesion in forebraill of adult ring dove (Streptopelia risoria)by means of autoradiography and *** in the adult avian is restricted to the telencephalon. In doves with bilateral electrolytic lesion of nucleus ectostriatum (E), the mean number of proliferating cells in the lateral ventricular zone (LVZ) and newborn neurons in the forebrain increased by 1.95 times and 2.38times respectively as compared with that in intact doves. The most relllarkable increase of neurogenesis induced by nucleus ectostriatum lesions was found at the anteriorposterior level 3 (L3), where the lesion site was *** results showed that the electrolytic brain lesion altered the distribution pattern of proliferating cells in theLVZ and resulted in increase of the number of newborn neurons in the non-VZ areas of forebrain. The changes in number and distribution pattern of proliferating cells in LVZ and newborn neurons in forebrain may be dependent on site of lesion. Studies on the relationship between proliferating cells in LVZ and newly generated neurons in non-VZ areas may help to understand the mechanism of brain plasticity and development.

关键词： Autoradiography neurogenesis brain lesion ring dove

A novel aberrant splicing of G_(sa) transcript in human leukemia cell lines

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Chinese Science Bulletin 1999年第4期44卷 340-344页

作者： YE Qinong, YAO Xiao, WANG Hengliang, ZHANG Shu, LIU Huaitian, SU Guofu, HUANG Cuifen and ZHOU Tingchong beijing Institute of Biotechnology, beijing 100071, china Department of Biology, Shaanxi normal College, Xi’an 710062, china beijing Medical university, School of Oncology, beijing 100036, china beijing Institute of Microbiology and Epidemiology, beijing 100071, china beijing Institute of Basic Medicine Sciences , beijing 100850, china beijing Institute of Biotechnology Beijing China Department of Biology Shaanxi Normal College Xi’an China School of Oncology Beijing Medical University Beijing China beijing Institute of Microbiology and Epidemiology Beijing China beijing Institute of Basic Medicine Sciences Beijing China

The α subunit of the stimulatory G protein, Gsα, is involved in the stimulation of adenylate cyclase pathway of signal transduction. The various Gsα mRNAs are generated either by alternative splicing or by using alternative promoter. A novel aberrant splicing of Gsα transcript in human leukemia cell lines is reported. The entire coding region of Gsα gene obtained, referred to as GsαLeu, was amplified by PCR with cDNA from Jurkat human leukemia cDNA library or the reverse-transcribed first strand cDNA from human leukemia cell line HL-60 as a template. The result of DNA sequencing indicated that,compared with originally reported Gsα, GsαLeu has two in-frame deletions, one in amino acid residues 23—249 and the other in amino acid residues 254—260, suggesting that G（sαLeu） may play an important role in leukemia. The complete coding region of GsαLu was inserted downstream of the thrombin site of pGEX-2T fusion protein expression vector and expressed in the form of GST/G(

关键词： Gsa splicing leukemia cloning and expression.

Theoretical studies on the mechanism of α-hydroxy-acid gas-phase elimination process and its substituent effect

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Chinese Journal of Chemistry 1997年第4期15卷 313-317页

作者： SONG,Wei-Ping HE,Shao-Ren FU,Xiao-YuanDepartment of Chemistry,beijing normal university,beijing 100875,china Department of Chemistry Beijing Normal University Beijing 100875 China

The α-hydroxy-acid gas-phase elimination process has been studied theoretically by HF/*** calculated results can be summed up as follows:(1) The elimination process is a stepwise *** the first step,a 3-membered ring intermediate is formed via a 5-membered ring transition state;while the product is formed in the second step via a 3-membered ring transition state.(2) The obtained results of the substituent effect show that the increase of electronic donation of the alkyl groups is favorable for the *** substituents which show the electron-withdrawing inductive effect (e.g.-Cl,-CN,-CF3) are unfavorable for this process.

关键词： α-Hydroxy-acid gas-phase elimination mechanism

The principle of relativity, kinematics and algebraic relations

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Science china(Physics,Mechanics & Astronomy) 2010年第4期53卷 591-597页

作者： GUO HanYing1, HUANG ChaoGuang2,3, WU HongTu4 & ZHOU Bin5 1Institute of Theoretical Physics, Chinese Academy of Sciences, beijing 100190, china 2Institute of High Energy Physics, Chinese Academy of Sciences, beijing 100049, china 3Theoretical Physics Center for Science Facilities, Chinese Academy of Sciences, beijing 100049, china 4Department of Mathematics, Capital normal university, beijing 100048, china 5Department of Physics, beijing normal university, beijing 100875, china Institute of Theoretical Physics Chinese Academy of Sciences Beijing China Institute of High Energy Physics Chinese Academy of Sciences Beijing China Theoretical Physics Center for Science Facilities Chinese Academy of Sciences Beijing China Department of Mathematics Capital Normal University Beijing China Department of Physics Beijing Normal University Beijing China

Based on the relativistic principle and the postulate of universal invariant constants (c, l), all kinematic symmetries can be set up as the subsets of the Umov-Weyl-Fock-Hua transformations for the inertial motions. ... 详细信息

关键词： principle of relativity with (c l) Umov-Weyl-Fock-Hua transformations kinematics special relativity triple

Cu(Ⅱ) Potentiation of Alzheimer Aβ1-40 Cytotoxicity and Transition on its Secondary Structure

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Acta Biochimica et Biophysica Sinica 2006年第11期38卷 765-772页

作者： Xue-Ling DAI~1 Ya-Xuan SUN~2 Zhao-Feng JIANG~2* 1 College of Life Science,Capital normal university,beijing 100037,china 2 College of Applied Sciences and Humanities,beijing Union university,beijing 100083,china College of Life Science Capital Normal UniversityBeijing 100037 China College of Applied Sciences and Humanities Beijing Union UniversityBeijing 100083 China

Mounting evidence has shown that dyshomeostasis of the redox-active biometals such as Cuand Fe can lead to oxidative stress,which plays a key role in the neuropathology of Alzheimer's disease（AD）.Here we demonstrate that with the formation of Cu（Ⅱ）·Aβ1-40 complexes,copper markedly potentiatesthe neurotoxicity exhibited by β-amyloid peptide （Aβ）.A greater amount of hydrogen peroxide was releasedwhen Cu（Ⅱ）·Aβ1-40 complexes was added to the xanthine oxidase/xanthine system detected by potassiumiodide *** bound to Aβ1-40 was observed by electron paramagnetic resonance（EPR） *** dichroism （CD） studies indicated that copper chelation could cause a structuraltransition of Aβ.The addition of copper to Aβ introduced an increase on β-sheet as well as α-helix,whichmay be responsible for the aggregation of Aβ.We hypothesized that Aβ aggregation induced by copper maybe responsible for local injury in *** interaction between Cu2+and Aβ also provides a possible mechanismfor the enrichment of metal ions in amyloid plaques in the AD brain.

关键词： Alzheimer’s disease Cu(Ⅱ)·Aβ1-40 complex neuron injury Aβ secondary structure

Landscape patterns and their evolutions in　the suburban ecotone──A case study of the eastern suburb of beijing

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Journal of Environmental Sciences 1994年第3期6卷 277-286页

作者： Yang Jurong,Zhang Hongmei,Huang Yi Institute of Environmental Science,beijing normal university,beijing 100875,china

The characteristics and evolutions of the landscape patterns in the suburban ecotone are studied on the basis of landscape-ecological maps of different years derived from the corresponding aerial photos The relationship between landscape patterns and urban economical development is ana- lyzed. The diversity index is used to characterize the features of the landscape patterns in the ecotone and define the location of Sharp change.

关键词： suburban ecotone landscape patterns diversity index.

Calculating model of mass action concentrations for Ag-Au-Cu melts

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Rare Metals 2002年第1期21卷 43-47页

作者： ZHANG Jian Metallurgy School, university of Science and Technology beijing, beijing 100083, china Metallurgy School University of Science and Technology Beijing 北京 100083

Based on phase diagrams and measured activities, the calculatingmodel of mass action concentrations for het- erogeneous meltsAg-Au-Cu was formulated. Calculated results agree with the improvedresults of recent research work, Showing that the model formulatedcan reflect the structural characteristics of these melts. In thismodel, without the help Of any empirical parameters, only threeequilibrium constants are used, hence it is simple, lear, andfavorable to the sim- Plification of calculation.

关键词： activity mass action concentration eutectic Solid solution