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公共投资与区域就业变动——基于动态面板数据模型的经验分析

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上海财经大学学报（哲学社会科学版） 2010年第6期12卷 54-62页

作者：苑德宇中国社会科学院财政与贸易经济研究所北京100836

本文构建了反映劳动力市场均衡就业量与公共基础设施水平之间关系的动态模型,分别利用全国29个省及东、中、西部各地区省份2002-2008年面板数据对公共投资的就业效应进行了实证分析。结果显示,就业存在较强的跨期路径依赖性;公路密度增... 详细信息

本文构建了反映劳动力市场均衡就业量与公共基础设施水平之间关系的动态模型,分别利用全国29个省及东、中、西部各地区省份2002-2008年面板数据对公共投资的就业效应进行了实证分析。结果显示,就业存在较强的跨期路径依赖性;公路密度增加仅在短期内促进了就业水平的提高;人均普通中学拥有率增加在短期内对就业有挤出作用,但在长期中却存在更大反方向效应;同类公共投资对就业变动的影响显示出一定区域差异性。

关键词：公共投资就业变动动态面板数据模型

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The Infection Process by a Green Fluorescent Protein-Tagged of Verticillium dahliae in Arabidopsis thaliana

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The Infection Process by a Green Fluorescent Protein-Tagged ...

中国植物病理学会2011年学术年会

作者： Zhao Pan~(1,2),Zhao Yun-long~(1,2),Zhao Jian-hua~(1,2),Duan cheng-guo~1,Guo hui-shan~(1*) (1.State Key Laboratory of Plant Genomics and National Center for Plant Gene Research(beijing), Institute of Microbiology,chinese academy of sciences,beijing,china 2.Graduate university of chinese academy of sciences,beijing,china)

＜正＞As a soil-borne phytopathogen,Verticillium dahliae Kleb（***） causes verticillium wilt diseases by infection through plant *** is known about the process of infection and ***,we report the first application of the hydroponic-culture Arabidopsis thaliana for exploration of the infection progress of *** seedlings cultured in liquid medium were inoculated with conidial suspension of a green fluorescent protein（GFP） -expressing isolate of ***（V592）.At an early infection stage,conidials randomly covered on surface of root-hairs *** germ tube emergence from the infected root surface,hyphal extended longitudinally along root epidermal *** certain hyphals were able to penetrate the root epidermal *** this process,there are no conspicuous structures,such as appressoria,formed,but a slightly swell at the hyphal apex,like the infection pegs,within cell junctions were observed,which direct penetration of hyphal to colonize the adjoining *** colonization progressed, elaborate hyphal networks were produced in vascular tissues and led to the eventual colonized the xylem vessels and extensive spread bidirectionally to stems and leaves or root *** grew along lateral root initiation points and staved the root tips were also *** data indicated that the root tip were not the initial infection point and V. dahliae does not develop a visible infection structures like other phytopathogens.

关键词： Arabidopsis hydroponic Verticillium dahiae GFP infection process

The Arabidopsis Spontaneous Cell Death1 gene, encoding a ζ-carotene desaturase essential for carotenoid biosynthesis, is involved in chloroplast development, photoprotection and retrograde signalling

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Cell Research 2007年第6期17卷 458-470页

作者： Haili Dong1,2 Yan Deng1,2 Jinye Mu1 Qingtao Lu3 Yiqin Wang1 Yunyuan Xu3 Chengcai Chu1 Kang Chong3 Congming Lu3 Jianru Zuo1 1 State Key Laboratory of Plant Genomics and National Plant Gene Research Center (beijing), Institute of Genetics and Developmental Biology, chinese academy of sciences, Beoing 100101, china 2 Graduate School, chinese academy of sciences, beijing 10003., china 3 Institute of Botany, chinese academy of sciences, beijing 100093, china InstituteofGeneticsandDevelopmentalBiologyChineseAcademyofSciencesBeijing100101China GraduateSchoolchineseacademyofsciences Beijing

Carotenoids, a class of natural pigments found in all photosynthetic organisms, are involved in a variety of physiologi-cal processes, including coloration, photoprotection, biosynthesis of abscisic acid (ABA) and chloroplast *** carotenoid biosynthesis has been well studied biochemically, the genetic basis of the pathway is not wellunderstood. Here, we report the characterization of two allelic Arabidopsis mutants, spontaneous cell death 1-1 (spcl-1)and spcl-2. The weak allele spcl-1 mutant showed characteristics of bleached leaves, accumulation of superoxide andmosaic cell death. The strong mutant allele spcl-2 caused a complete arrest of plant growth and development shortlyafter germination, leading to a seedling-lethal phenotype. Genetic and molecular analyses indicated that SPC1 encodesa putative ζ-carotene desaturase (ZDS) in the carotenoid biosynthesis pathway. Analysis of carotenoids revealed thatseveral major carotenoid compounds downstream of SPC1/ZDS were substantially reduced in spcl-1, suggesting thatSPC1 is a functional ZDS. Consistent with the downregulated expression of CAO and PORB, the chlorophyll contentwas decreased in spcl-1 plants. In addition, expression of Lhcb1.1, Lhcb1.4 and RbcS was absent in spcl-2, suggestingthe possible involvement of carotenoids in the plastid-to-nucleus retrograde signaling. The spcl-1 mutant also displaysan ABA-deficient phenotype that can be partially rescued by the externally supplied phytohormone. These results suggestthat SPC1/ZDS is essential for biosynthesis of carotenoids and plays a crucial role in plant growth and development.

关键词： carotenoid biosynthesis cell death chloroplast development photoprotection Arabidopsis SPC1/ZDS

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UNIFORM PERSISTENCE AND GLOBAL ATTRACTIVITY FOR NONAUTONOMOUS COMPETITIVE SYSTEMS WITH DISPERSION

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Journal of Systems Science & Complexity 2002年第3期15卷 307-314页

作者： SONGXinyu CHENLansun DepartmentofMathematics XingangTeachersCollegeHenan464000China InstituteofMathematics AcademyofMathematicsandSystemsScienceChinesAcademyofSceiencesBeijing100080China

In this paper, we consider a nonautonomous competitive model with dispersion and a finite number of discrete delays. The system, which consists of two Lotka-Volterra patches, has two competitors: one can disperse between the two patches, but the other is confined to one patch and cannot disperse. Our purpose is to demonstrate that the dispersion rates have no effect on the uniform persistence of the solutions of the system. Furthermore, we establish the conditions under which the system admits a positive periodic solution which attracts all solutions.

关键词： Uniform persistence global attractivity dispersion.

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Protection of Mice with a Divalent Tuberculosis DNA Vaccine Encoding Antigens Ag85B and MPT64

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Acta Biochimica et Biophysica Sinica 2004年第4期36卷 269-276页

作者： Xia TIAN, Hong CAI, and Yu-Xian ZHU* The National Laboratory of Protein Engineering and Plant Genetic Engineering, Peking university, beijing 100871, china The National Laboratory of Protein Engineering and Plant Genetic Engineering Peking UniversityBeijing 100871 China

DNA vaccine may be a promising tool for controlling tuberculosis development. However, vaccines encoding single antigens of mycobacterium did not produce protective effect as BCG did. In the present study, we evaluated the immunogenicity and protective efficacy of a divalent DNA vaccine encoding two immunodominant antigens Ag85B and MPT64 of Mycobacterium tuberculosis. We found that both humoral and Th1-type (high IFN-γ, low IL-4) cellular responses obtained from the divalent DNA vaccine group were significantly higher than that conferred by BCG. RT-PCR results showed that antigens were expressed differentially in various organs in divalent DNA vaccine group. The survival rate for mice treated with the divalent DNA vaccine after challenging with high doses of virulent M. tuberculosis H37Rv was significantly higher than that of the BCG group or any of the single DNA vaccine group. Significant differ- ences were also found between the single and divalent DNA vaccinated mice in terms of body, spleen and lung weight. Bacterial loading decreased about 2000-fold in lungs and about 100-fold in spleens of divalent DNA vaccinated mice when compared with that of the control group. We conclude that our divalent DNA vaccine may be a better choice for controlling tuberculosis disease in animals.

关键词： tuberculosis divalent DNA vaccine immunogenicity protection

Simulation Research of Parametric Methods for Multi-baseline SAR Tomography

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Simulation Research of Parametric Methods for Multi-baseline...

2007 Asian and Pacific Conference on Synthetic Aperture Radar(APSAR 2007)

作者： Wang Bin 1 2 3 Wang Yanping 1 2 Hong Wen 1 2 Wu Yirong 1 2 1The National Key Laboratory of Microwave Imaging Technology beijing P.R. china 2The Institute of Electronics chinese academy of sciences beijing P.R. china 3The Graduate university of chinese academy of sciences beijing P.R. china

Multi-baseline SAR tomography is an extension of SAR interferometry. It uses multi-baseline data to obtain the distribution of scatterers along the height direction and realize three-dimensional imaging of the investigated scene. The parametric method can be used to realize SAR tomography. Super-resolution method based on modern spectrum analysis and inverse processing with singular values decomposition （SVD） are the main algorithms of parametric method. We analyze the principle of multi-baseline SAR tomography. The steps of the two algorithms are introduced,and the imaging results and efficiencies of the two algorithms are compared. We simulate the two algorithms with spaceborne SAR parameters,and get the tomographic images of the investigated targets.

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Granulocyte-macrophage colony-stimulating factor DNA prime-protein boost strategy to enhance efficacy of a recombinant pertussis DNA vac-cine

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Acta Pharmacologica Sinica 2006年第11期27卷 1487-1494页

作者： Qing-tian LI~(2,3,5)Yong-zhang ZHU~(2,3,5)Jia-you CHU~(2,6)Ke DONG~3 Ping HE~3 Chun-yan FENG~3 Bao-yu HU~3 Shu-min ZHANG~4 Xiao-kui GUO~(3,6)2 Institute of Medical Biology,Peking Union Medical College and chinese academy of Medical sciences,Kunming 650118,china 3 Department of Medical Microbiology and Parasitology,Shanghai Jiao Tong university School of Medicine,Shanghai 200025,china 4 chinese National Institute for the Control of Pharmaceutical and Biological Products,beijing 100050,china InstituteofMedicalBiology PekingUnionMedicalCollegeandChineseAcademyofMedicalSciencesKunming650118China DepartmentofMedicalMicrobiologyandParasitology ShanghaiJiaoTongUniversitySchoolofMedicineShanghai200025China

Aim:To investigate a new strategy to enhance the efficacy of a recombinantpertussis DNA *** strategy is co-injection with cytokine plasmids asprime,and boosted with purified homologous ***:A recombinantpertussis DNA vaccine containing the pertussis toxin subunit 1(PTS 1),fragmentsof the filamentous hemagglutinin(FHA)gene and pertactin(PRN)gene encodingfilamentous hemagglutinin and pertactin were ***/c mice were im-munized with several DNA vaccines and antigen-specific antibodies anti-PTS1,anti-PRN,anti-FHA,cytokines interleukin(IL)-10,IL-4,IFN-γ,TNF-α,and spleno-cyte-proliferation assay were used to describe immune ***:Therecombinant DNA vaccine could elicit similar immune responses in mice as that ofseparate plasmids encoding the 3 fragments,*** immunized withDNA and boosted with the corresponding protein elicited more antibodies thanthose that received DNA as *** particular,when the mice were co-immu-nized with murine granulocyte-macrophage colony-stimulating factor plasmidsand boosted with proteins,all 4 cytokines and the 3 antigen-specific antibodieswere significantly increased compared to the pVAX1 ***-PTS1,anti-FHA,IL-4 and TNF-α elicited in the colony stimulating factor(CSF)prime-proteinboost group showed significant increase compared to all the other ***:This prime and boost strategy has proven to be very useful in im-proving the immunogenicity of DNA vaccines against pertussis.

关键词： granulocyte-macrophage colony-stimulating factor pertussis DNA vaccines

Gene expression and molecular characterization of a thermostable trehalose phosphorylase from Thermoanaerobacter tengcongensis

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Science china(Life sciences) 2005年第3期48卷 221-227页

作者： REN Yuanyuan 1,2 , DAI Xiuyu 1 , ZHOU Jian 1 , LIU Jingfang 1 , PEI Huadong 1,2 & XIANG Hua 1 1. State Key Laboratory of Microbial Resources and Center for Molecular Microbiology, Institute of Microbiology, chinese academy of sciences, beijing 100080, china 2. Graduate School of chinese academy of sciences, beijing 10003., china State Key Laboratory of Microbial Resources and Center for Molecular Microbiology Institute of Microbiology Chinese Academy of Sciences Beijing100080 China Graduate School of chinese academy of sciences Beijing100037 China State Key Laboratory of Microbial Resources and Center for Molecular Microbiology Institute of Microbiology Chinese Academy of Sciences Beijing100080 China

A gene encoding the trehalose phosphorylase (TreP), which reversibly catalyzes trehalose degradation and synthesis from α-glucose-1-phosphate (α-Glc-1-P) and glucose, was cloned from Thermoanaerobacter tengcongensis and successfully expressed in Escherichia coli. The overexpressed TreP, with a molecular mass of approximately 90 kDa, was determined by SDS-PAGE. It catalyzes trehalose synthesis and degradation optimally at 70℃ (for 30 min), with the optimum pHs at 6.0 and 7.0, respectively. It is highly thermostable, with a 77% residual ac- tivity after incubation at 50℃ for 7 h. Under the optimum reaction conditions, 50 μg crude en- zyme of the TreP is able to catalyze the synthesis of trehalose up to 11.6 mmol/L from 25 mmol/L α-Glc-1-P and 125 mmol/L glucose within 30 min, while only 1.5 mmol/L out of 250 mmol/L tre- halose is degraded within the same time period. Dot blotting revealed that the treP gene in T. tengcongensis was upregulated in response to salt stress but downregulated when trehalose was supplied. Both results indicate that the dominant function of the T. tengcongensis TreP is catalyzing trehalose synthesis but not degradation. Thus it might provide a novel route for indus- trial production of trehalose.

关键词： gene expression, Thermoanaerobacter tengcongensis, trehalose phosphorylase, dot blot.

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Nanometer Materials for Lithium-ion Batteries

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Nanometer Materials for Lithium-ion Batteries

2003年纳米和表面科学与技术全国会议

作者： Xuejie Huang Institute of Physics, chinese academy of sciences, beijing 100080, china Email: xjhuang@***

This paper summarizes our research work of lithium storage in carbonaceous materials with nano pores, nano BCN tubes, and nano-sized alloys and nanometer cover layer on cathode materials can large improve their cycling performance. Hard carbon spherules with only nano pores can store more lithium compared with graphite, which evidences that lithium

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