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Parameter estimation for whole-body kinetic model of FDG metabolism

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Progress in Natural Science:Materials International 2006年第11期16卷 1164-1170页

作者： CUI Yunfeng~1, BAI Jing~1**, CHEN Yingmao~2.and TIAN Jiahe~2.1. Department of Biomedical Engineering, Tsinghua university, beijing 100084, China 2. Department of Nuclear {2., General Hospital of PLA, beijing 100853, China) [a]Department of Biomedical Engineering Tsinghua University Beijing China [b]Department of Nuclear medicine General Hospital of PLA Beijing China

Based on the radioactive tracer [ ~ 18 F]2.fluoro-2.deoxy-D-glucose （FDG）, positron emission tomography （PET）, and compartment model, the tracer kinetic study has become an important method to investigate the glucose metabolic kinetics in human body. In this work, the kinetic parameters of three-compartment and four-parameter model for the FDG metabolism in the tissues of myocardium, lung, liver, stomach, spleen, pancreas, and marrow were estimated through some dynamic FDG-PET experiments. Together with published brain and skeletal muscle parameters, a relatively complete whole-body model was presented. In the liver model, the dual blood supply from the hepatic artery and the portal vein to the liver was considered for parameter estimation, and the more accurate results were obtained using the dual-input rather than the single arterial-input. The established whole-body model provides the functional information of FDG metabolism in human body. It can be used to further investigate the glucose metabolism, and also be used for the simulation and visualization of FDG metabolic process in human body.

关键词： compartment model FDG PET parameter estimation.

Density-functional formula for strongly correlated systems

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Progress in Natural Science:Materials International 2005年第5期15卷 395-401页

作者： WANG Huaiyu1*, HAN Rushan2.and CHEN Nanxian1(1. Department of Physics, Tsinghua university, beijing 100084, China 2. Department of Physics, Peking university, beijing 100871, China) Department of Physics Tsinghua University Beijing 100084 China Department of Physics Peking University Beijing 100871 China

Density functional method is applied for strongly correlated systems. Based on the assumption that the systems are composed of electrons in singly-occupied orbitals and those in doubly-occupied orbitals, a set of self-consistent equations are obtained by standard variation procedure. The equations consist of two parts. One part is to solve the wave functions of the electrons in singly-occupied orbitals and the other is to solve the wave functions of the electrons in doubly-occupied orbitals. The physical meanings of the terms appearing in the equations are discussed.

关键词： density-functional theory strongly correlated systems doubly-occupied orbital two-particle wave function self-consistent equations.

Technical development of proteomics

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Chinese Science Bulletin 1999年第16期44卷 1441-1447页

作者： WAN Jinghong and HE Fuchu1.Chongqing Medical university, Chongqing 400046, China 2. beijing Institute of Radiation {2., beijing 100850, China Corresponding author Chongqing Medical university Chongqing China beijing Institute of Radiation medicine Beijing China

Proteome research is an important complementarity for the genome research, which uses quantitative protein-level measurements to characterize biological process. Proteome techniques include two aspects. One is two-dimensional electrophoresis, which is the unique technology to separate the components of proteome. The other is identification of the

关键词： proteome two-dimensional electrophoresis image analysis peptide-mass fingerprinting database.

Molecular structure and biological function of proliferating cell nuclear antigen

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Progress in Natural Science:Materials International 2007年第10期17卷 1127-1135页

作者： Song Nanmeng1, Sang Jianli1 and Xu Heng2.1. Institute of Cell Biology, College of Life Science, beijing Normal university, beijing 100875, China 2. Emory university School of medicine, GA 30332. USA) Institute of Cell Biology College of Life Science Beijing Normal University Beijing 100875， China Emory university School of medicine GA 30332 USA

Proliferating cell nuclear antigen (PCNA) is the core component of replication complex in eukaryote. As a processive factor of DNA polymerase delta, PCNA coordinates the replication process by interacting with various replication proteins. PCNA appears to play an essential role in many cell events, such as DNA damage repair, cell cycle regulation, and apoptosis, through the coordination or organization of different partners. PCNA is an essential factor in cell proliferation, and has clinical significance in tumor research. In this article we review the functional structure of PCNA, which acts as a function switch in different cell events.

关键词： PCNA Function Switch PCNA Binding Motif Cell Cycle DNA Replication DNA Repair.

外语高校助推中外人文交流的高质量特色发展路径

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北京教育（高教） 2024年第7期 12-14页

作者： beijing International Studies university 北京第二外国语学院

构建高质量高等教育体系需要高校错位竞争、特色办学和多样化发展。北京第二外国语学院始终秉承“中外人文交流”使命,坚定高水平特色大学办学类型,坚持以外语为主体、旅游为特色、多学科协同发展,在培育翻译后备力量、培养胜任中外人... 详细信息

构建高质量高等教育体系需要高校错位竞争、特色办学和多样化发展。北京第二外国语学院始终秉承“中外人文交流”使命,坚定高水平特色大学办学类型,坚持以外语为主体、旅游为特色、多学科协同发展,在培育翻译后备力量、培养胜任中外人文交流和国际传播的外语人才方面表现出显著优势,在推动国家文化和旅游高质量发展方面提供全方位智力支持,在服务北京国际交往中心功能建设方面作出突出贡献,探索形成了外语高校特色办学的高质量发展路径。

关键词：高水平特色型大学中外人文交流外语旅游

The numerical method for three-dimensional impact with friction of multi-rigid-body system

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Science China(Physics,Mechanics & Astronomy) 2006年第1期49卷 102-118页

作者： ZHAO Zhen1,2. LIU Caishan2.& CHEN Bin2.1. beijing Institute of Graphic Communication, beijing 102.00, China 2. Department of Mechanics & Engineering Science, Peking {2., beijing 100871, China beijing Institute of Graphic Communication Beijing 102600 China Department of Mechanics & Engineering Science Peking University Beijing 100871 China

The differential equations for planar impacts reduce to an algebraic form, and can be easily solved. For three dimensional impacts with friction, there is no closed-form solution, and numerical integration is required due to the swerve behavior of tangential impulse during collisions. The dynamic governing equations in the impact process are built up in impulse space based on the Lagrangian equation in this paper. The coefficient of restitution defined by Poisson is used as the condition of impact termination. A valid nu- merical method for solving three-dimensional frictional impact of multi-rigid body system is established. The singular cases of tangential movement in sticking point are especially noticed and analyzed. Several examples are present to reveal the different kinds of tan- gential movement modes varied with the normal impulse during collision.

关键词： multi-rigid body, impact, friction.

The study of two-color excitation upconversion of Pr(0.5)Yb(3):ZBLAN

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Science China(Physics,Mechanics & Astronomy) 2006年第2期49卷 169-177页

作者： CHEN Xiaobo1 & SONG Zengfu2.1. Applied Optics beijing Area Major Laboratory, Analysis and testing center, beijing Normal {2., beijing 100875, China 2. Peking {2., Physics School, beijing 100871, China Applied Optics beijing Area Major Laboratory Analysis testing center Beijing Normal University Beijing 100875 China Physics School Peking University Beijing 100871 China

The excited state absorption upconversion of Pr(0.5)Yb(3):ZBLAN glass material, under two-color excitation of the 960 nm semiconductor laser and the Xe lamp light simultaneously, is reported in this article. It was found that the upconversion emission spectra of 480.1, 519.0, 601.9 and 631.8 nm coincide with the common emission spectra. Meanwhile, the upconversion-excitation spectrum has three obvious peaks under two-color excitation, and they respectively correspond to the 856.0 nm upconversion ex-citation transition [1G4(Pr3+)→1I6(Pr3+) and 1G4(Pr3+)→3P1(Pr3+)], the 789.0 nm upconver-sion excitation transition 1G4(Pr3+)→3P2.Pr3+), and the 803.7 nm upconversion excitation transition 3H6(Pr3+)→1D2.Pr3+). The upconversion excitation transition 1G4(Pr3+)→1I6(Pr3+) is strong because its oscillator strength f = 2..040×10?6 is large, which results in a large peak appearing in the upconversion excitation spectrum. That is just the new interesting two-color excitation upconversion luminescence phenomenon of Pr(0.5)Yb(3):ZBLAN induced by one laser and one continuous normal light simultaneously.

关键词： upconversion volumetric three-dimensional display two-color excitation.

Explanation of the mechanism of carcinogenesis and syntheses of anticancer agents with high selectivity

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Science China Chemistry 2006年第1期49卷 44-62页

作者： DAI Qianhuan1,2.1. Center of Chemistry and Bioengineering of Cancer Research, beijing Polytechnic university (Now known as beijing Univer-sity of Technology), beijing 10002., China 2. Center of Environmental Sciences, Peking university, beijing 100871, China 1. Center of Chemistry and Bioengineering of Cancer Research Beijing Polytechnic University Beijing 100022 China 2. Center of Environmental Sciences Peking University Beijing 100871 China

In 1979, the mechanism of chemical carcinogenesis, a challenging anddifficult scientific problem pending for a number of years, was explained by Dai Qianhuan. Themechanism named di-region theory predicted that a carcinogen always metabolizes to form a specialbi-functional alky-lating agent. This agent induces cross-linkages between the complementary basepairs in DMA and switches on initial mutageneses in genomes including point and frameshiftmutations. This, in turn, induces further deep mutageneses including the production of variouschimeric chromosomes, deletions and other aberrations found in genomes. In the end this initiatescarcinogenesis of the whole cell through the reverse transcription mechanism after a lengthyincubation period. Recently, this laboratory has verified that physical carcinogenesis, includingthe oncogenesis induced by radiation and asbestos as well as the carcinogenesis induced byendogenous factors such as estrogen or diethyl-stilbestrol switch on carcinogenesis by inducing theformation of cross-linkages between the complementary base pairs in DNA. Di-region theory has nowbeen supported by many experimental observations such as mutational spectra of various *** potential for carcinogenesis, teratogenesis, sterility and mutagenesis lumped together asgenetic toxicity appears to originate almost uniformly from the cross-linking between complementarybases, i.e. malignant cross-linking, which is in accordance with di-region theory. Other forms ofcross-linking between non-complementary bases, benign cross-linkings, show bi-functional alkylationanticancer activity but lack genetic toxicity. The predictable design and synthesis of a highselectivity anticancer agent with high efficacy and low genetic toxicity, a goal long pursued incancer chemotherapy, have been realized for the first time in this laboratory by inhibitingmalignant and heightening benign cross-linking using the principles of di-region theory. A series ofpatented new anticanc

关键词： mechanism of carcinogenesis, di-region theory, minoplatin, selectivity of anticancer agent, cross-linking between DNA bases, anticancer platinum complexes, predictive design of anticancer agent, second generation anticancer agent.

Empirical likelihood confidence regions of the parameters in a partially linear single-index model

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Science China Mathematics 2005年第10期48卷 1333-1348页

作者： XUE Liugen~1 & ZHU Lixing~2.1. College of Applied Sciences,beijing university of Technology,beijing 10002.,China 2. Department of Mathematics,Hong Kong Baptist university,Hong Kong,China 1. College of Applied Sciences Beijing University of Technology 100022 Beijing China 2. Department of Mathematics Hong Kong Baptist University Hong Kong China

In this paper, a partially linear single-index model is investigated, and three empirical log-likelihood ratio statistics for the unknown parameters in the model are suggested. It is proved that the proposed statistics are asymptotically standard chi-square under some suitable conditions, and hence can be used to construct the confidence regions of the parameters. Our methods can also deal with the confidence region construction for the index in the pure single-index model. A simulation study indicates that, in terms of coverage probabilities and average areas of the confidence regions, the proposed methods perform better than the least-squares method.

关键词： partially linear single-index model, empirical likelihood, confidence region, chi-square distribution, coverage probability.