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Present status and development on biological nitrogen fixation research in china

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Chinese Science Bulletin 2003年第10期48卷 954-960页

作者： SHEN Shihua & JING Yuxiang Key Laboratory of Photosynthesis and Plant-Environment MolecularPhysiology, institute of Botany, Chinese Academy of Sciences, beijing 100093, china Key Laboratory of Photosynthesis and Plant-Environment Molecular Physiology Institute of Botany Chinese Academy of Sciences Beijing 100093 China

This presentation introduces the advances inbiological nitrogen fixation research abroad, in particular,describes the great progress and achievements on itsresearch in china as follows: collection of rhizobial resources and establishment of the largest database of Rhizobium inchina, correction and development of Rhizobium taxonomy in international; discovery of a couple of nif genes,identification and unification of linkage among the nif gene operons of Klebsiella pneumoniae, finding of regulative mechanism of positive regulation nif gene and its sensitivity to oxygen, temperature; finding of the activity of nodulation gene nodD3 product in Sinorhizobium meliloti which is notcontrolled by flavonoid produced from its host alfalfa;finding of the association between expression of genes coding the products for carbon utilization and nitrogen metabolism and their regulations; chemical synthesis of nodulationfactor of Sinorhizobium meliloti; constructions of engineered nitrogen fixers and utilization in practice based on theresearch of gene expression and regulation; chemicalsimulation of the structure and function of nitrogenase and bringing forward the model of nitrogenase active center for the first time in international and synthesis of modelcompounds which were paid attention by colleagues abroad. Finally, the development of nitrogen fixation research inchina in future has been put forward, suggesting that the nifgene regulation and its role in providing crops with nitrogen element, signal transduction and molecular interactions between Rhizobium and legume, coupling between carbonand nitrogen metabolisms, nitrogen fixation andphotosynthesis, and functional genomics of nitrogen-fixing nodule symbiosis, etc., would be actively worked on.

关键词：现状发展生物固氮技术中国固氮酶基因表达微生物植物相互作用化学模型

Finding Signals for Plant Promoters

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genomics, Proteomics & Bioinformatics 2003年第1期1卷 68-73页

作者： Weimou Zhenginstitute of Theoretical Physics, Chinese Academy of Sciences, beijing 100080, china beijing genomicsinstitute, Chinese Academy of Sciences, beijing 101300, china institute of Theoretical Physics Chinese Academy of Sciences Beijing 100080 China beijing genomics institute Chinese Academy of Sciences Beijing 101300 China

The strongest signal of plant promoter is searched with the model of single motif with two types. It turns out that the dominant type is the TATA-box. The other type may be called TATA-less signal, and may be used in gene finders for promoter recognition. While the TATA signals are very close for the monocot and the dicot, their TATA-less signals are significantly different. A general and flexible multi-motif model is also proposed for promoter analysis based on dynamic programming. By extending the Gibbs sampler to the dynamic programming and introducing temperature, an efficient algorithm is developed for searching signals in plant promoters.

关键词： for on is as et Pro Finding Signals for Plant Promoters been of into

Molecular dynamics simulations of the Li-ion diffusion in the amorphous solid electrolyte interphase

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Chinese Chemical Letters 2023年第11期34卷 346-349页

作者： Jianxin Tian Taiping Hu shenzhen Xu Rui Wen CAS Key Laboratory of Molecular Nanostructure and Nanotechnology CAS Research/Education Center for Excellence in Molecular SciencesBeijing National Laboratory for Molecular Science(BNLMS)Institute of ChemistryChinese Academy of SciencesBeijing 100190China University of Chinese Academy of Sciences Beijing 100049China School of Materials Science and Engineering Peking UniversityBeijing 100871China

The solid electrolyte interphase(SEI),a passivation film covering the electrode surface,is crucial to the lifetime and efficiency of the lithium-ion(Li-ion)*** the Li-ion diffusion mechanism within possible components in the mosaic-structured SEI is an essential step to improve the Li-ion conductivity and thus the battery ***,we investigate the Li-ion diffusion mechanism within three amorphous SEI components(i.e.,the inorganic inner layer,organic outer layer,and their mixture with 1:1 molar ratio)via ab initio molecular dynamic(AIMD)*** simulations show that the Li-ion diffusion coefficient in the inorganic layer is two orders of magnitude faster than that in the organic ***,the inorganic layer makes a major contribution to the Li-ion ***,we find that the Li-ion diffusivity in the organic layer decreases slightly with the increase of the carbon chain from the methyl to ethyl owing to the steric hindrance induced by large ***,our current work unravels the Li-ion diffusion mechanism,and provides an atomic-scale insight for the understanding of the Li-ion transport in the SEI components.

关键词： Molecular dynamics Amorphous solid electrolyte interphase Li-ion diffusion

The mathematical equivalence property of photonic bandgaps in photonic crystals and electronic bandgaps in electronic crystals for 1D and 2D systems

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The mathematical equivalence property of photonic bandgaps i...

Replication priority of hepatitis C virus genotype 2a in a Chinese cohort

CCAST“光子晶体”研讨会

作者： Zhengbiao Ouyang and Jingzhen LiSolid State Photonics Laboratory, College of Scientific Researches and Developments, shenzhen University, shenzhen 518060, chinaDaozhong Zhang Optical Physics Laboratory, institute of Physics, Chinese Academy of Sciences, beijing 100080, china

＜正＞Starting from the Schr（?）dinger equation of electron waves and the Maxell‘s waveequation of photons,we find that the wave equation of electrons in electronic crystalsand that of s-polarized photons in photonic crystals in 1D and 2D systems haveexactly the same *** mathematical equivalence property of photonic bandgapsand electronic handgaps in 1D and 2D systems for s-polarized photons exists both for

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Replication priority of hepatitis C virus genotype 2a in a C...

Pharmacokinetics of sifuvirtide, a novel anti-HIV-1 peptide, in monkeys and its inhibitory concentration in vitro1

2012年中国药学大会暨第十二届中国药师周

作者： Zhen Yang1,2,Yong-Xin Yu 2,Hong-Zhong Zhang3,Gui-Fang Shang4,Jia-Liang Gao5,Zong-Gen Peng1,Jian-Dong Jiang1,1.institute of Medicinal Biotechnology,Chinese Academy of Medical Sciences and Peking Union Medical College,beijing,100050,china 2. National institute for the Control of Pharmaceutical and Biological Products,beijing,100050,china 3. Langfang Blood Center,LangFang,065000,Hebei,china 4. shenzhen Blood Center,shenzhen,518035,Guangdong ,china 5. Chengdu Blood Center,Chengdu,610041,Sichuan,china

Background and Aim: HCV genotypes have been documented in clinical *** goal of this study is to learn viral replication capacity of different HCV genotypes in human ***: 491 otherwise healthy Chinese blood donors with positive HCV antibody reaction were employed in the *** subjects were not being treated with antiviral drugs *** genotyping was determined followed by serum viral load *** antibody reaction against HCV Core,NS3,NS4 and NS5 epitope antigens was analyzed,respectively,for each of the ***: Genotyping analysis showed that among these individuals 6.7% was infected with genotype 1a,41.5% with 1b,36.0% with 2a,6.7% with 2b,2.6% with 3a,1.8% with 3b,2.4% with 6 and 2.0% *** 1b and 2a were the predominant ones in this Chinese cohort,causing 77.6% HCV *** the genotype groups,individuals infected with genotype 2a had a HCV RNA viral load （108copies/ml） over 100-fold （2.3log） higher than that infected with other genotypes （104-105copies/ml）,indicating a replication priority of genotype *** is no correlation between HCV genotype and antibody response against HCV Core,NS3,NS4 and NS5 epitope *** appears that the amplification advantage of genotype 2a results from its nature of favorable interaction with host cellular ***: HCV genotype 1b and 2a are both the predominant genotypes in china;of the seven HCV subtypes analyzed genotype 2a possesses a significant replication priority in this Chinese cohort.

关键词： HCV genotype viral load antibody response

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Acta Pharmacologica Sinica 2005年第10期26卷 1274-1280页

作者： Shu-jia DAI~2, Gui-fang DOU~3, Xiao-hong QIAN~(4,5), Hai-feng SONG~4, Zhong-ming TANG~2, De-sheng LIU~2, Xiu-wen LIU~2, Liu-meng YANG~6, Yong-tang ZHENG~6, Qing LIANG~7 ~2 Laboratory of Metabolism of Biotechnology Derived Drugs, beijing institute of Radiation Medicine, beijing 100850 ~3 Laboratory of Drug Metabolism and Pharmacokinetics, beijing institute of Transfusion Medicine, beijing 100850 ~5 Laboratories of genomics and Proteomics, beijing institute of Radiation Medicine, beijing 100850 ~6 Laboratory of Molecular hnmunopharmacology, Kunming institute of Zoology, Chinese Academy of Sciences, Kunming 650223 ~7 FusoGen Pharmaceuticals Inc, Tianjin 300051, china LaboratoryofMetabolismofBiotechnologyDerivedDrugs BeijingInstituteofRadiationMedicineBeijing100850 LaboratoryofDrugMetabolismandPharmacokinetics BeijingInstituteofTransfusionMedicineBeijing100850

Aim: To study the pharmacokinetics of sifuvirtide, a novel anti-human immunodeficiency virus （HIV） peptide, in monkeys and to compare the inhibitory concentrations of sifuvirtide and enfuvirtide on HIV-1-infected-cell fusion. Methods: Monkeys received 1.2 mg/kg iv or sc of sifuvirtide. An on-line solid-phase extraction procedure combined with liquid chromatography tandem mass spectrometry （SPELC/MS/MS） was established and applied to determine the concentration of sifuvirtide in monkey plasma. A four-127I iodinated peptide was used as an internal standard. Fifty percent inhibitory concentration (IC50) of sifuvirtide on cell fusion was determined by co-cultivation assay. Results: The assay was validated with good precision and accuracy. The calibration curve for sifuvirtide in plasma was linear over a range of 4.88-5000μg/L, with correlation coefficients above 0.9923. After iv or sc administration, the observed peak concentrations of sifuvirtide were 10 626±2 886μg/L and 528±191μg/L, and the terminal imination half-lives (T1/2) were 6.3±0.9 h and 5.5±1.0 h, respectively. After sc, Tmaxwas 0.25-2h, and the absolute bioavailability was 49%±13%. Sifuvirtide inhibited the syncytium formation between HIV-1 chronically infected cells and uninfected cells with an IC50of 0.33μg/L. Conclusion: An on-line SPE-LC/MS/MS approach was established for peptide pharmacokinetic studies. Sifuvirtide was rapidly absorbed subcutaneously into the blood circulation. The T1/2of sifuvirtide was remarkably longer than that of its analog, enfuvirtide, reported in healthy monkeys and it conferred a long-term plasma concentration level which was higher than its IC50in vitro.

关键词： sifuvirtide pharmacokinetics HIV HIV fusion inhibitors enfuvirtide on-line solid-phase extraction macaque

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逆流色谱溶质出峰顺序的预测

色谱 2002年第6期20卷 526-529页

作者：周玉杰陈福明李总成清华大学化工系北京100084 深圳清华大学研究院广东深圳518057

根据逆流色谱保留方程可知,溶质的出峰顺序主要取决于其在互不混溶的两液相间分配系数的大小顺序。以饱和及不饱和脂肪酸乙酯、2,4 二硝基苯胺基脂肪醇和对硝基苯基葡萄糖甙等结构较为简单、极性差别较大的溶质系列为研究对象,应用修正... 详细信息

根据逆流色谱保留方程可知,溶质的出峰顺序主要取决于其在互不混溶的两液相间分配系数的大小顺序。以饱和及不饱和脂肪酸乙酯、2,4 二硝基苯胺基脂肪醇和对硝基苯基葡萄糖甙等结构较为简单、极性差别较大的溶质系列为研究对象,应用修正的通用基团活度系数(UNIFAC)(Dortmund)模型,通过相平衡计算,预测了它们在含水或不含水的溶剂体系中分配系数的变化趋势,并与前人的工作进行了对比。结果表明,由该方法预测出的相似结构溶质分配系数的顺序基本上与实验值相同,其中对饱和脂肪酸乙酯在己烷乙腈(体积比为1∶1)体系中分配系数的预测最好。这种预测方法的建立将对逆流色谱非电解质溶剂体系的选择具有较大的指导意义。

关键词：溶质出峰顺序预测逆流色谱通用基团活度系数分配系数 UNIFAC模型分离

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飞行管理系统实时仿真研究

系统仿真学报 2008年第S2期20卷 333-336页

作者：齐林梁斌程农哈尔滨工业大学深圳研究生院深圳518055 清华大学自动化系导航与控制研究中心北京100084

介绍了一种使用Simulink/RTW(Real-Time Workshop)建模工具和Tornado/VxWorks嵌入式实时操作系统进行飞行管理系统快速原型的方法。首先介绍了飞行管理系统的主要功能以及飞行管理系统的主要工作方式。然后介绍了基于RTW/VxWorks的实时... 详细信息

介绍了一种使用Simulink/RTW(Real-Time Workshop)建模工具和Tornado/VxWorks嵌入式实时操作系统进行飞行管理系统快速原型的方法。首先介绍了飞行管理系统的主要功能以及飞行管理系统的主要工作方式。然后介绍了基于RTW/VxWorks的实时仿真方法,并对实时仿真平台的配置作了详细的说明。最后设计了飞行管理系统实时仿真的框架,并在RTW/VxWorks实时仿真平台上对飞行管理系统部分核心功能进行了实时分布式仿真。

关键词：飞行管理系统实时仿真 RTW VxWorks

Jackknife and Bootstrap Tests of the Composition Vector Trees

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genomics, Proteomics & Bioinformatics 2010年第4期8卷 262-267页

作者： Guanghong Zuo1,2, Zhao Xu1,3, Hongjie Yu1,4, and Bailin Hao1,5,6 1T-Life Research Center & Department of Physics, Fudan University, Shanghai 200433, china 2Shanghai institute of Applied Physics, Chinese Acadamy of Sciences, Shanghai 201800, china 3Applied Biosystems, Inc., beijing 100027, china 4Fudan-VARI Center for Genetic Epidemiology, Fudan University, Shanghai 200433, china 5institute of Theoretical Physics, Chinese Acadamy of Sciences, beijing 100190, china 6Santa Fe institute, Santa Fe, NM 87505, USA. T-Life Research Center & Department of Physics Fudan University Shanghai 200433 China

Composition vector trees （CVTrees） are inferred from whole-genome data by an alignment-free and parameter-free method. The agreement of these trees with the corresponding taxonomy provides an objective justification of the inferred phylogeny. In this work, we show the stability and self-consistency of CVTrees by performing bootstrap and jackknife re-sampling tests adapted to this alignment-free approach. Our ultimate goal is to advocate the viewpoint that time-consuming statistical re-sampling tests can be avoided at all in using this alignment-free approach. Agreement with taxonomy should be taken as a major criterion to estimate prokaryotic phylogenetic trees.

关键词： composition vector phylogeny topological distance bootstrap jackknife CVTree