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Optimal reactions for the synthesis of superheavy nucleus ^(270)Hs

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Science china(Physics,Mechanics & Astronomy) 2006年第6期49卷 641-648页

作者： LIU Zuhua1,3.& BAO Jingdong1,2 1. Key Laboratory of Beam Technology and Material Modification of Ministry of Education, beijing Normal university, beijing 100875, {3. 2. Physics department, beijing Normal university, beijing 100875, {3. 3. {3. Institute of Atomic Energy, beijing 102413. {3. Key Laboratory of Beam Technology and Material Modification of Ministry of Education Beijing Normal University Beijing China china Institute of Atomic Energy Beijing China Physics department Beijing Normal University Beijing China

The superheavy nucleus 270Hs is expected to be a “double-magic” deformed nucleus. We have calculated its cross sections of evaporation residue for the reactions 248Cm(26Mg,4n)270Hs, 244Pu(3.Si,4n)270Hs, 23.U(3.S,4n)270Hs and 226Ra(48Ca,4n)270Hs using a two-parameter Smoluchowski equation. It is found from our results that 226Ra(48Ca,4n)270Hs and 23.U(3.S,4n)270Hs are two optimal reactions for the synthesis of the superheavy nucleus 270Hs due to their large negative Q-values.

关键词： diffused fusion barrier,Smoluchowski equation,superheavy nuclei.

Characterization for commutators of n-dimensional fractional Hardy operators

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Science china Mathematics 2007年第10期50卷 1418-1426页

作者： Zun-wei FU~(1,2) Zong-guang LIU~3.Shan-zhen LU~(1+) Hong-bin WANG~3.~1 School of Mathematical Sciences,beijing Normal university,beijing 100875,{3. ~2 department of Mathematics,Linyi Normal university,Linyi 276005,{3. ~3.department of Mathematics,{3. university of Mining and Technology (beijing),beijing 100083,{3. School of Mathematical Sciences Beijing Normal University Beijing China department of Mathematics Linyi Normal University Linyi China department of Mathematics China University of Mining and Technology (Beijing) Beijing China

In this paper,it was proved that the commutator H_(β,b)generated by an n-dimensional fractional Hardy operator and a locally integrable function b is bounded from L^(p1)(R^n)to L^(p2)(R^n)if and only if b is a CMO(R^... 详细信息

关键词： n-dimensional fractional Hardy operator, commutator, C(M)O function, homogeneous Herz space

Direct CP violation in hadronic B decays

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Science china(Physics,Mechanics & Astronomy) 2006年第3期49卷 357-366页

作者： HONG Bihai1,2 & Lü Caidian3.1. department of Physics, Lishui university, Lishui 3.3.00,china 2. department of Physics, Shanghai Jiaotong university, Shanghai 20003., china 3. Institute of High Energy Physics, beijing 100049,china department of Physics Lishui University Lishui China department of Physics Shanghai Jiaotong University Shanghai China Institute of High Energy Physics Beijing China

There are different approaches for the hadronic B decay calculations, recently. In this paper, we upgrade three of them, namely factorization, QCD factorization and the perturbative QCD approach based on kT factorization, using new parameters and full wave functions. Although they get similar results for many of the branching ratios, the direct CP asymmetries predicted by them are different, which can be tested by recent experimental measurements of B factories.

关键词： CP violation hadronic B decay factorization.

Up-regulation of Cartilage Oligomeric Matrix Protein Gene Expression by Insulin-like Growth Factor-Ⅰ Revealed by Real Time Reverse Transcription-Polymerase Chain Reaction

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Acta Biochimica et Biophysica Sinica 2006年第10期38卷 677-682页

作者： Hua TIAN~(1,2*) Ioannis STOGIANNIDIS~2 1 department of Orthopaedics,Peking university third {3.,beijing 100083,china 2 Coxa {3. for Joint Replacement,Biokatu 6 b,Tampere 3.101,Finland department of Orthopaedics Peking University Third HospitalBeijing 100083 China Coxa hospital for Joint Replacement Biokatu 6 bTampere 33101 Finland

Cartilage oligomeric matrix protein (COMP) strengthens cartilage by binding to type Ⅱ and typeⅨ collagen-forming bridges between collagen *** was hypothesized that perhaps one or more anabolicgrowth factors such as insulin-like growth factor-Ⅰ (IGF-Ⅰ),fibroblast growth factor-1 (FGF-1) or plateletderived growth factor-BB (PDGF-BB) increase COMP gene *** effects on primary humanchondrocytes and the chondrogenic cell line ATDC5 were studied using real time reverse transcript-poly-merase chain reaction (RT-PCR) for ***-Ⅰ,but not the FGF-1 or PDGF-BB,up-regulatedCOMP gene expression by approximate 5-fold in human adult chondrocytes in a dose-and ***-Ⅰ exerted similar effects on ATDC5 *** from these real time RT-PCR experimentswere confirmed by transfecting into ATDC5 cells a full-length mouse COMP promoter cloned upstream of aluciferase reporter *** stimulation with IGF-Ⅰ,the luciferase reporter activity increased by about *** conclusion,IGF-Ⅰ seems to be an important positive regulator of COMP,which may play animportant role in an attempted repair of either traumatized or degenerated cartilage.

关键词： cartilage oligomeric matrix protein (COMP) insulin-like growth factor-Ⅰ(IGF-Ⅰ) gene expression

Hydrogen sulfide ameliorates vascular calcification induced by vitamin D3.plus nicotine in rats

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Acta Pharmacologica Sinica 2006年第3期27卷 299-306页

作者： Sheng-ying WU~(2,6) Chun-shui PAN~3.Bin GENG~3.Jing ZHAO~3.Fang YU~3.Yong-zheng PANG~3.Chao-shu TANG~4 Yong-fen QI~(3.4,5) ~2Institute of Cardiovascular Disease,Peking university First hospital.beijing 10003. ~3.3. of Physiology and Pathophysiology,Peking university Health Science Center,beijing 100083,china,~4Key Laboratory of Molecular Cardiovascular Science,Ministry of Education,beijing 100083,china Institute of Cardiovascular Disease Peking University First Hospital Beijing China department of Physiology and Pathophysiology Peking University Health Science Center Beijing China Key Laboratory of Molecular Cardiovascular Science Ministry of Education Beijing China

Aim:To investigate the role of the endogenous cystathionine γ-synthase(CSE)/hydrogen sulfide(H2S)pathway in vascular calcification in ***:A ratvascular calcification model was established by administration of vitamin D3.plusnicotine(VDN).The amount of CSE and osteopontin(OPN)mRNA was deter-mined by using semi-quantitative reverse-transcription polymerase chain *** calcium content,45Ca2+accumulation and alkaline phosphatase(ALP)activitywere measured.H,S production and CSE activity were ***:yonKossa staining produced strong positive black/brown staining in areas amongthe elastic fibers of the medial layer in the calcified *** calcium content,45Ca2+accumulation and ALP activity in calcified arteries increased by 6.77-,1.42-,and 1.87-fold,respectively,compared with *** expression of the OPNgene was upregulated(P3..8%,40.75% and 63.5% lowerin the low-dosage NariS group than in the VDN group,respectively(P3.9%,3..8 % and 46.2% lower in the aorta in the high-dosage NariS group than in theVDN group,respectively(P<0.01).The expression of the OPN gene ***:The production of H,S,and CSE activity were de-creased and CSE gene expression was downregulated in rats with vascularcalcification.H2S can ameliorate vascular calcification,suggesting that the H2S/CSE pathway plays a regulatory role in the pathogenesis of vascular calcification.

关键词： hydrogen sulfide cystathionine-lyase vascular calcification mRNA

A MODIFIED ALGORITHM OF FINDING AN ELEMENT OF CLARKE GENERALIZED GRADIENT FOR A SMOOTH COMPOSITION OF MAX-TYPE FUNCTIONS A MODIFIED ALGORITHM OF FINDING AN ELEMENT OF CLARKE GENERALIZED GRADIENT FOR A SMOOTH COMPOSITION OF MAX-TYPE FUNCTIONS

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Journal of Computational Mathematics 2000年第5期18卷 513-520页

作者： Yan Gao (department of Basic Science, china university of Mining and Technology-{3., beijing 100083, china) （北京）中国矿业大学北京 100083

This paper refers to Clarke generalized gradient for a smooth composition of max-type functions of the form: f(x) = g(x, maxj∈J1 f1j(x),''', maxj∈Jm fmj(x)), where x ∈Rn, Ji, i = 1,''',m are finite index sets, g and fij,j ∈ Ji, i = 1,... )m, are continuously differentiable on Rm+n and Rn, respectively. In a previous paper) we proposed an algorithm of finding an element of Clarke generalized gradient for f, at a point. In that paper, finding an element of Clarke generalized gradient for f, at a point, is implemented by determining the compatibilities of systems of linear inequalities many times. So its computational amount is very expensive. In this paper) we will modify the algorithm to reduce the times that the compatibilities of systems of linear inequalities have to be determined.

关键词： Nonsmooth optimization Clarke generalized gradient Max-type function.

Study on NDVI-T_s space by combining LAI and evapotranspiration

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Science china Earth Sciences 2006年第7期49卷 747-754页

作者： HAN Lijuan1,2,3. WANG Pengxin4, YANG Hua1,2,3. LIU Shaomin1,2,3.& WANG Jindi1,2,3.1. Research Center for Remote Sensing and GIS, School of Geography, beijing Normal university, beijing 100875, {3. 2. State Key Laboratory of Remote Sensing Science, beijing 100875, {3. 3. beijing Key Laboratory for Remote Sensing of Environment and Digital Cities, beijing 100875, {3. 4. department of Information Management, College of Information and Electronic Engineering, {3. Agricultural university, beijing 100083, {3. Research Center for Remote Sensing and GIS School of Geography Beijing Normal University Beijing China State Key Laboratory of Remote Sensing Science Beijing China beijing Key Laboratory for Remote Sensing of Environment and Digital Cities Beijing China department of Information Management College of Information and Electronic Engineering China Agricultural University Beijing China

This paper focuses on interpreting the different spatial relationships between NDVI and Ts, a triangular or a trapezoid, and on analyzing transformation conditions, the physical and ecological meanings of the vegetation index-surface temperature space as well. Further, we use the Tempera-ture-Vegetation Dryness Index (TVDI) to explain the existent meaning of a triangular space after NDVI reaches its saturated state by employing the relationships between NDVI, LAI and evapotranspiration. The specific relations between NDVI and Ts are useful for describing, validating and updating land surface models.

关键词： NDVI, land surface temperature, evapotranspiration, leave area index.

Honokiol inhibits arterial thrombosis through endothelial cell protection and stimulation of prostacyclin

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Acta Pharmacologica Sinica 2005年第9期26卷 1063-1068页

作者： He HU~1 Xiao-xue ZHANG~1 Yin-ye WANG~(1,2) Shi-zhong CHEN~3. department of Molecular and Cellular Pharmacology beijing university {3.,china 3.department of Natural Medicinal Chemistry,School of Pharmaceutical Sciences,Peking university {3.,china department of Molecular and Cellular Pharmacology Beijing University Beijing China department of Natural Medicinal Chemistry School of Pharmaceutical Sciences Peking University Beijing China

Aim:To study the effect of honokiol on arterial thrombosis and endothelial ***:Rabbit platelet aggregation was performed with Born's turbid *** was produced by the endothelial injury stimulated with electric *** aortic endothelial cells（RAEC）were cultured and cell viability was assessedusing the MTT *** oxide（NO）concentrations in serum-free media ofRAEC were determined using the kinetic cadmium-reduction *** stablemetabolite prostacyclin was measured in serum-free media of RAEC ***:Honokiol（3..6-3.6 lamol/L）decreased rabbit plate-let aggregation in vitro in a concentration-dependent manner,while intravenouslyinjection of honokiol（0.12-12 μg/kg）significantly inhibited rabbit platelet aggre-gation induced by collagen ex *** the electrical current-stimulated carotidthrombosis model in rats,honokiol（5-50 μg/kg,iv）prolonged the thrombus oc-clusion time in a does-dependent *** vitro honokiol（0.3.6-3..6 μmol/L）effectively protected cultured RAEC against oxidized low density lipoprotein（ox-LDL ）injury,and significantly increased 6-keto-PGF1α（the stable metabolite ofprostacyclin）in serum-free media of *** also increased NO level inRAEC serum-free medium at a lower concentration range（0.03.6-0.3.6 μmol/L）,but honokiol 3.76 μmol/L decreased NO ***:Honokiol is a potentarterial thrombosis *** cell protection and the stimulation ofprostacyclin release may be its main anti-thrombosis *** ofNO release in endothelial cells may play a role,but it is not a key factor.

关键词： honokiol platelet aggregation thrombosis cultured cells endothelium prostacyclin nitric oxide

Solving the input data in error correc-tion of optical fabrication by finite Fourier coefficient algorithm

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Science china(Technological Sciences) 2006年第1期49卷 50-60页

作者： CHENG Haobo1,2, SUN Guozheng3.& FENG Zhijing2 1. department of Optical Engineering, beijing Institute of Technology, beijing 100081, {3. 2. department of Precision Instruments and Mechanology, Tsinghua university, beijing 100084, {3. 3. {3. North Industries Group Corporation, beijing 100089, {3. department of Optical Engineering Beijing Institute of Technology Beijing China department of Precision Instruments and Mechanology Tsinghua University Beijing China china North Industries Group Corporation Beijing China

A free-form lens (FFL) is a special surface that is difficult to be fabricated. FFL are usually fabricated by computer-controlled optical surfacing (CCOS) technique. During CCOS, the material removal amount is determined by the unit removal function (URF) convoluting with the input data――the dwell time. When the removal amount and the URF are known, how to solve the input data involves the special algorithm――deconvolution. Usually, the input data are solved by virtue of low pass filter or iterative methods. However, an approximation solution would destroy the machining stability nec-essary to perform precisely CCOS. In this paper, to solve the input data, a new method that is based on the finite Fourier coefficient is put forward. It can give a continuous and accurate solution for fabricating choice. Several parameters are simulated, which influ-ence the process of CCOS, and evaluating on the effect of the method is also carried out. Experimental results verify that this method is suitable for guiding the manufacturing of high precision FFL.

关键词： optical fabrication, computer controlled optical surfacing, free-form lens, finite Fourier coefficient, error correction.