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Efficient estimation for additive hazards regression with bivariate current status data

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Science china Mathematics 2012年第4期55卷 763-774页

作者： TONG XingWei 1,,HU Tao 2 & SUN JianGuo 3.4 1 School of Mathematical sciences,Beijing Normal university,Beijing 100875,china 2 School of Mathematical sciences,Capital Normal university,Beijing 100048,china 3.School of Mathematics,jilin university,changchun 13.012,china 4 department of Statistics,university of Missouri,Columbia,MO 65211,USA School of Mathematical sciences Beijing Normal University Beijing China School of Mathematical sciences Capital Normal University Beijing China School of Mathematics Jilin University Changchun China department of Statistics University of Missouri Columbia USA

This paper discusses efficient estimation for the additive hazards regression model when only bivariate current status data are available. Current status data occur in many fields including demographical studies and tumorigenicity experiments （Keiding, 1991; Sun, 2006） and several approaches have been proposed for the additive hazards model with univariate current status data （Linet M., 1998; Martinussen and Scheike, 2002）. For bivariate data, in addition to facing the same problems as those with univariate data, one needs to deal with the association or correlation between two related failure time variables of interest. For this, we employ the copula model and an efficient estimation procedure is developed for inference. Simulation studies are performed to evaluate the proposed estimates and suggest that the approach works well in practical situations. An illustrative example is provided.

关键词： bivariate current status data copula model counting processes efficient estimation joint survivalfunction

Numerical　modeling　of　radionuclide　migration　in　porous　media　with　nonequilibrium　sorption

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Journal of Environmental sciences 1996年第1期8卷 86-93页

作者： Chen Jiajun Dai Jie(department of Environmental Engineering,Tsinghua university,Beijing 100084,china)(Tianjin Institute of Geological Investigation and Research,Tianjin 3.0191,china)Xu Zhaoyi Tian Kaiming(changchun university of earth sciences,changchun 1

When radionuclides migrate in porous media with water serving as carrier, the mechanism of sorption and desorption is not negligible. nonequilibrium conditions exist in sorption and desorption. In this paper,a numerical model of radionuclide migration with nonequilibrium sorption was *** algorithm of numerical descretizing and direct substituting was adopted in coupling of the convective-dispersive equation and the nonequilibrium sorption isotherm in this model ,and this makes it easier to solve the model numerically.A quantitative analysis is made for the first time that the influence of nonequilibrium sorption, represented by the rate coefficient which shows how quickly the nonequilibrium condition in sorption and desorption reaches equilibrium on the migration of radionuclide,and results show that it affects the migration perceptibly. Finally the model was verified by using the observed data of radionuclide migration test conducted in the field, and which clarified its availability.

关键词： adionuclide migration sorption and desorption nonequilibrium sorption rate coefficient.

Study on the Mode Losses and Bending Lossesof Hollow-core Optical Fiber of GeO2 andSiO2 Bases for Transmitting CO2 Laser Energy

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Chinese Journal of Lasers 1996年第1期B5卷 27-32页

作者： HOU Lantian (department of Physics,jilin university,changchun 13.023.{3.)SUN Yingzhi (Light Communication department,changchun Poat and Telecommunication Institte,changchun 13.012,{3.)ZHAO Bin(department of Physics,Science and Technology university of jilin Univ Changchun China

The transmitting losses of several lower modes for four kinds of straight and bent circular hollow optical fibers （waveguide） made up with GeO2 or SiO2 and doped with PbO or Sb2O3.respectively are calculated. The results show that the HE11 mode has the minimum loss in straight waveguide and the loss of TM01 mode in bent waveguide is the minimun.

关键词： hollow-core optical fiber low-order mode bending loss

A local spin evaluation into the active site models of [2Fe2S] ferrodoxin [Fe_2S_2(SR)_4]^(2-) (R=-H, -CH_3.

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Science china Chemistry 2007年第3期50卷 327-334页

作者： WEI JiChong1,2, WANG Yan3.& JU GuanZhi2,3.1 department of Chemistry, Hainan Normal university, Haikou 571158, china 2 State Key Laboratory of Theoretical and Computational Chemistry, {3., changchun 13.023. china 3.department of Chemistry, Nanjing university, Nanjing 210093. china department of Chemistry Hainan Normal University Haikou China State Key Laboratory of Theoretical and Computational Chemistry Jilin University Changchun China department of Chemistry Nanjing University Nanjing China

To test the feasibility of local spin theory of Davidson and Clark for ferrodoxin clusters, the models [Fe2S2(SR)4]2- (R=-H, -CH3. are chosen for evaluation. This purpose is realized by calculating the local spin expectation values , , and mA and discussing the connection between these expected values and the Heisenberg spin model (HSM) and the Noodleman broken-symmetry approach. In practical calculation, the spin-unrestricted Hartree-Fock (UHF) and spin-polarized density functional theory (DFT) are used and the calculational qualities of these two methods are also discussed. In addition, the theoretical magnetic coupling constants JAB of these models are calculated by various computational schemes for comparison with both theoretical and experimental results previously reported.

关键词： local spin iron-sulfur protein model density function theory magnetic coupling constant

BAF Complex Is Closely Related to and Interacts with NF1/CTF and RNA Polymerase Ⅱ in Gene Transcriptional Activation

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Acta Biochimica et Biophysica Sinica 2005年第7期37卷 440-446页

作者： Li-Hui ZHAO~(1,2) Xue-Qing BA~1 Xiao-Guang WANG~3.Xiao-Juan ZHU~1 Li WANG~1 Xian-Lu ZENG~1 1 Institute of Genetics and Cytology,Northeast Normal university,changchun 13.024,china 2 College of Agronomy,{3. Agricultural university,changchun 13.118,china 3.department of Biology,changchun Normal College,changchun 13.03.,china Institute of Genetics and Cytology Northeast Normal UniversityChangchun 130024 China College of Agronomy Jilin Agricultural UniversityChangchun 130118 China department of Biology Changchun Normal CollegeChangchun 130032 China

Brg-or hBrm-associated factor (BAF) complexes,a chromatin-remodeling complex family ofmammalian cells,facilitate transcriptional activity by remodeling nucleosome ***1 is the coresubunit of Brg-associated factor *** the present study,we investigated the spatial relationshipbetween Brg1 and nuclear factor 1 (NF1/CTF) and RNA polymerase Ⅱ (RNAP Ⅱ) upon gene transcriptionalactivation in vivo by employing immuno-gold *** data showed that Brg1 was closely co-localizedwith NF1/CTF and RNAP Ⅱ in HeLa ***,the co-immunoprecipitation assay further revealedthat Brg1 can be isolated together with NF1/CTF and RNAP Ⅱ in the ConA-stimulated,but not the resting,T *** combined results suggested that BAF complexes can interact with NF1/CTF and RNAPⅡ,and this interaction is closely dependent on the activation of gene transcription.

关键词： BAF complex NF1/CTF RNAP Ⅱ gene transcription

Discovery and analysis of ultra-micro grinding grain texture in slipping lamellae of ductile-brittle zone

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Science china earth sciences 2004年第3期47卷 265-271页

作者： GE Heping1, SUN Yan1, LU Xiancai1, ZHU Wenbin1, GUO Jichun1, LIU Deliang2 & Chi-yuen Wang3.1. department of earth sciences, Nanjing {3., State Key Laboratory of Mineral Deposit, Nanjing 210093. china 2. department of earth and Space sciences, {3. of Science and Technology of china, Hefei 23.026, china 3. department of Geology and Geophysics, {3. of California, Berkeley, CA 94720, USA department of earth sciences Nanjing University State Key Lab. of Mineral Deposit Nanjing 210093 China Dept. of earth and Space sciences Univ. of Science/Technology of China Hefei 230026 China department of Geology and Geophysics University of California Berkeley CA 94720 United States

Based on the observation of the deep bore cores sampled from the State of Cali-fornia, USA, preferred arranged particulate concentration belts were found in the ultra-slipping lamellae. And the same phenomenon was found again later in the bore cores from the petroleum basin in the Northern Shaanxi Province. It may be the product of the dynamic processes involv-ing tumbling, grinding and compresso-shearing functions, so the spherical particulates with ul-tra-size of nm and mm are called grinding grain. The formation of the grinding grains is related with the ductile-brittle deformation, the lateral pressure of the slipping, and the very low grade of dynamic metamorphism of the rocks. Based on the systematic analysis, it is indicated that some elements like Nb and Ta are enriched in the grinding grains in the granitic rocks because of the chemical differentiation, and that the slipping lamellae bearing grinding grains in mudstone with smear efficiency prove a perfect seal for oil and gas reservoirs. Meanwhile, the paper provides bases for the studies on the fast stick-slip movement and shear paradigm.

关键词： slipping lamellae, grinding grain texture, ductile-brittle deformation, smear efficiency.

Complete quantum circuit of Haar wavelet based MRA

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Chinese Science Bulletin 2005年第16期50卷 1796-1798页

作者： HE Yuguo1,2 & SUN Jigui1,3.1. College of Computer Science and Technology, jilin university, changchun 13.012, china 2. {3. of Computer Science and Engineering, Beijing Institute of Technology, Beijing 100081, china 3. Key Laboratory of Computation and Knowledge Engineering of Min-istry of Education, jilin university, changchun 13.012, china College of Computer Science and Technology Jilin University Changchun China department of Computer Science and Engineering Beijing Institute of Technology Beijing China Key Laboratory of Computation and Knowledge Engineering of Ministry of Education Jilin University Changchun China

Wavelet analysis has applications in many ar- eas, such as signal analysis and image processing. We pro- pose a method for generating the complete circuit of Haar wavelet based MRA by factoring butterfly matrices and con- ditional perfect shuffle permutation matrices. The factoriza- tion of butterfly matrices is the essential part of the design. As a result, it is the key point to obtain the circuits of I 2t ⊕ W ⊕ I 2n ? 2t ?2. In this paper, we use a simple means to de- velop quantum circuits for this kind of matrices. Similarly, the conditional permutation matrix is implemented entirely, combined with the scheme of Fijany and Williams. The cir- cuits and the ideas adopted in the design are simple and in- telligible.

关键词：量子计算量子算法量子电路 Haar微波 MRA

Ultra-microbes are the minerogenetic constructors of oceanic polymetallic nodules

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Chinese Science Bulletin 1997年第8期42卷 617-624页

作者： CHEN Jianlin, ZHANG Fusheng and BIAN Lizeng1 Second Institute of Oceanography, State Oceanic Administration, Hangzhou 3.0012, china 2 Center for Materials Analysis, Nanjing university, Nanjing 210093. china {3., Nanjing university, Nanjing 210093. china Second Institute of Oceanography State Oceanic Administration Hangzhou China Centu for Materials Analysis Nanjing University Nanjing China department of earth sciences Nanjing University Nanjing China

Polymetallic nodules (mangnese nodules) are a typical kind of manganese oncolites The distribution of smooth sur-face and knobbly manganese nodules is closely related to the geological background of the mine field. A systematic study on their inner laminae structure and features suggests that they are the products of millions of years reproduction and accumulation of the recently found Miniactinomyces chinensis and Spirisophaerospora pacijica .

关键词： oceanic manganese nodule stromatolite ultra-microbe biolite.

Garnet-bearing Granulite Facies Rock Xenoliths from Late Mesozoic Volcaniclastic Breccia, Xinyang, Henan Province

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Acta Geologica Sinica(English Edition) 2001年第4期75卷 445-451页

作者： ZHENG Jianping, SUN Min, LU Fengxiang, WANG Chunyangand ZHONG Zengqiu Faculty of earth sciences, china {3. of Geosciences, Wuhan 43.074, china department of earth sciences, The {3. of Hong Kong, china china Univ Geosci Fac Earth Sci Wuhan 430074 Peoples R China Univ Hong Kong Dept Earth Sci Hong Kong Hong Kong Peoples R China

This paper presents the primary results of petrologic, mineralogical and petrochemical studies of garnet-bearing granulite facies rock xenoliths from Xinyang, Henan Province. These xenoliths, which are found in a pipe of late Mesozoic volcaniclastic breccia, are of high density (3.13.3.3. g/cm3. and high seismic velocity (Vp = 7.04–7.3. km/s), being products of underplating of basaltic magmas and had experienced granulite facies metamorphism. The underplating and metamorphism took place before the eruption of the host rock. Petrographical studies and equilibrium T-P calculations show that these xenoliths were captured at a 49 km depth and experienced at least a 16 km uplift before they were captured. The dynamics of the uplift could be related to the continent-continent collision between the North china plate and the Yangtze plate during the Triassic.

关键词： granulite facies mafic rock xenolith uplift Xinyang