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几种超分辨率荧光显微技术的原理和近期进展

生物化学与生物物理进展 2009年第12期36卷 1626-1634页

作者：吕志坚陆敬泽吴雅琼陈良怡北京市科学技术情报研究所北京100044 中国科学院生物物理研究所北京100101

在生命科学领域,人们常常需要在细胞内精确定位特定的蛋白质以研究其位置与功能的关系.多年来,宽场/共聚焦荧光显微镜的分辨率受限于光的阿贝/瑞利极限,不能分辨出2.0nm以下的结构.近年来,随着新的荧光探针和成像理论的出现,研究者开发... 详细信息

在生命科学领域,人们常常需要在细胞内精确定位特定的蛋白质以研究其位置与功能的关系.多年来,宽场/共聚焦荧光显微镜的分辨率受限于光的阿贝/瑞利极限,不能分辨出2.0nm以下的结构.近年来,随着新的荧光探针和成像理论的出现,研究者开发了多种实现超出普通共聚焦显微镜分辨率的三维超分辨率成像方法.主要介绍这些方法的原理、近期进展和发展趋势.介绍了光源的点扩散函数(point spread function,PSF)的概念和传统分辨率的定义,阐述了提高xy平面分辨率的方法.通过介绍单分子荧光成像技术,引入了单分子成像定位精度的概念,介绍了基于单分子成像的超分辨率显微成像方法,包括光激活定位显微技术(photoactivated localization microscopy,PALM)和随机光学重构显微技术(stochastic optical reconstruction microscopy,STORM).介绍了两大类通过改造光源的点扩散函数来提高成像分辨率的方法,分别是受激发射损耗显微技术(stimulated emission depletion,STED)和饱和结构照明显微技术(saturated structure illumination microscopy,SSIM).比较了不同的z轴提取信息的方法,并阐述了这些方法与xy平面上的超分辨率显微成像技术相结合所得到的各种三维超分辨率显微成像技术的优劣.探讨了目前超分辨率显微成像的发展极限和方向.

关键词：超分辨率荧光显微技术点扩散函数 PALM STORM STED SSIM

A model for assessing effects of climate change on runoff in china

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Progress in Natural Science:Materials International 2003年第9期 63-69页

作者： SU Fengge and XIE Zhenghui(LASG, Institute of Atmospheric Physics, chinese academy of sciences, beijing 10002.,{2.)

A model is established for assessing the effects of climate change on runoff in china based on the land surface parameter-ization scheme variable infiltration capacity (VIC). The entire area of china is represented by 2.04 cells with a resolution of 60km×60 km for each cell. Forcing data, soil and vegetation parameters needed by the VIC model for the entire area of china are prepared. Dailyforcing data, which are obtained from 740 stations between 1980 and 1990, are interpolated to the 60 km×60 km grid system. The VICmodel is run on every grid cell over the whole china, and a routing scheme is run offline with daily input of surface runoff and drainagefrom the VIC to get hydrograph at basin outlets. The spatial patterns of simulated runoff and mean annual precipitation are consistent verywell. The results of monthly streamflow simulations over the Huaihe and Weihe River basins indicate that there is a good agreement be-tween the observed and simulated values, and also initially indicate the rationalit

关键词： land surface parameterization scheme runoff evaluation model.

Investigation and protection strategies of fishes of Lhasa River

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Investigation and protection strategies of fishes of Lhasa R...

中国鱼类学会2.08年学术研讨会

作者： CHEN Feng~(1,2.,CHEN Yi-Feng~1 (1.Institute of Hydrobiology,chinese academy of {2.,Wuhan 43.072.china 2.The Graduate School of chinese academy of sciences,beijing 10003.,china)

＜正＞Lhasa River is the biggest tributary of Yarlung Zangbo *** fish fauna comprised 13.fish species and a natural bastard,belonging to Schizothoracinae,Nemacheilinae and Sisoridae. Disturbed by human activities,plen...

关键词：

Digital Ocean Oriented Data Processing and Information Service Systems

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Digital Ocean Oriented Data Processing and Information Servi...

第二十七届中国控制会议

作者： Wang Xiaomin 1,2.Zhang Xin 1,Chi Tianhe 1 1.Institute of Remote Sensing Applications,chinese academy of {2.,beijing 100101,P.R.china 2.Graduate University of chinese academy of sciences,beijing 10003.,P.R.china

Digital Ocean is one of important digital industries based on the concept of Digital *** a macro complex systematic engineering,the Digital Ocean is an ongoing task in *** mission of the Digital Ocean is to build an information system and develop methods for creating digital representations,or models,of ocean variables and *** gathering,processing,analyzing,visualizing and making data and information widely available,the Digital Ocean project can help provide integrated information on historical,current and future states of ocean and coastal *** paper analyzes data acquisition and information requirements of Digital *** on the analysis of the information needs,the data processing chain and methods of the Digital Ocean are brought *** then it presents two Digital Ocean oriented information service systems,one-stop portal based information services system for IOOS of Taiwan strait and 3.D globe based Digital Ocean prototype.

关键词： Digital ocean Data processing Information service systems

The fragment of Paleo-Tethys ophiolite from central Qiangtang, Tibet:Geochemical evidence of meta-basites in Guoganjianian

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Science china Earth sciences 2007年第9期50卷 1302-1309页

作者： ZHAI QingGuo1,2. LI Cai2.& HUANG XiaoPeng2.1 Institute of Geology, {3. academy of Geological {2., beijing 10003., china 2.College of Earth {2., Jilin University, Changchun 13.061, china 1. Institute of Geology Chinese Academy of Geological Sciences Beijing 100037 China 2. College of Earth sciences Jilin University Changchun 130061 China

N-MORB-type metabasites are discovered in the Guoganjianian area, central Qiangtang, Tibet, which are mainly metagabbro with cumulate structure and metabasalt. The rocks are distributed nearly from west to east unconformably underlying the Wanghuling Group of upper Triassic. On the basis of geo- chemical analysis, we find that the content of SiO2.is 43.03.―53.42., and TiO2.1%―2.67%, Al2.3.16.75%―2..52., CaO 7.03.―11.13., K2. 0.05%―0.3.%; the REE pattern is slight depletion or flat, and the trace spider diagram is like that of N-MORB, so we consider that the metabasite was formed under the setting of mid-ocean ridge or adult back-arc basin, and it is the fragment of Paleo-Tethys ophiolite.

关键词： Qiangtang, metabasite, Paleo-Tethys, ophiolite

The observation of pyrenoids of order Ulvales collected from Qingdao coast

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The observation of pyrenoids of order Ulvales collected from...

庆祝中国藻类学会成立3.周年暨第十五次学术讨论会

作者： Linhong Teng~(1,2. Lanping Ding~(1**) and Xiaoli Hu~3.(1.Institute of Oceanology,chinese academy of {2.,Qingdao 2.6071,china 2.Graduate University of chinese academy of sciences,beijing 100049,china 3.College of marine life science,Ocean University of china,Qingdao 2.6003.china)

＜正＞Pyrenoids found in green algal Order Ulvales have important taxonomical *** pyrenoids of several usual kinds of green algae collected along the Qingdao coast were *** the use of light microscopy,the morphology and distribution of pyrenoids,with its change by different parts of frond and time period,the optimal conditions are *** basal parts of frond have more distinct pyrenoids with average diameter 2.42.m in Enteromorpha *** some species,pyrenoids are not clear,and darkness can make them more *** process of pyrenoid in different algae is *** found that in ***,pyrenoids disappear faster than those in *** cells of most green algae observed,pyrenoids appear as single spherical ***,the pyrenoids of marginal parts are more observable than those of the center parts.

关键词： Order Ulvales morphology pyrenoid taxonomy apoptosis process

喷灌条件下土壤NO_3.--N含量的空间变异性研究

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土壤学报 2004年第6期41卷 991-995页

作者：高鹭胡春胜毛仁钊中国科学院地理科学与资源研究所中国科学院石家庄农业现代化研究所石家庄050021

作物生长所需的养分主要来源于土壤,因而土壤作为作物生长的营养库,其养分的变异必然会引起作物生长的变异.北方旱地土壤氮素形态一般以硝态氮为主,所以开展土壤NO-3.N含量空间变异性研究对于科学合理地制定农田施肥方案,提高氮肥利用率... 详细信息

作物生长所需的养分主要来源于土壤,因而土壤作为作物生长的营养库,其养分的变异必然会引起作物生长的变异.北方旱地土壤氮素形态一般以硝态氮为主,所以开展土壤NO-3.N含量空间变异性研究对于科学合理地制定农田施肥方案,提高氮肥利用率,促进变量施肥技术的发展,实现精确施肥具有重要意义[1～3..灌区田间实际情况表明,在土壤质地相同的区域内,土壤特性(物理、化学及生物性质)在同一时刻,各个空间位置上的量值并不相同[4].喷灌是一种节水效果十分显著,适应性较强的灌水方式,相比传统灌溉其湿润层要浅,对硝态氮的淋洗以及对环境的影响必然也较传统灌溉不同.因此利用地统计学方法,研究喷灌条件下土壤中硝态氮的空间变异性,对NO-3.N的空间监测、寻找土壤空间变异研究与作物生长空间变异研究的最佳切合点以及研究喷灌条件下硝态氮对环境的影响程度具有重要的指导意义.……

关键词：土壤氮素作物生长养分喷灌空间变异性 N含量 NO3.- 形态硝态氮

Contribution of Root and Microbial Respiration to Soil CO_2.Efflux and Their Environmental Controls in a Humid Temperate Grassland of Japan

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Pedosphere 2009年第1期19卷 31-39页

作者： WANG Wei FENG Jiang T. OIKAWA Department of Ecology College of Urban and Environmental Sciences and Key Laboratory for Earth Surface Processes of the Ministry of Education Peking University Beijing 100871 （China） School of Urban and Environmental sciences Northeast Normal University Changchun 130024 （China） Institute of Biological sciences University of Tsukuba Tsukuba Ibaraki 305-8572 （Japan）

Soil CO2.efflux, root mass, and root production were investigated in a humid temperate grassland of Japan over a growing season （Apr. to Sep.） of 2.05 to reveal seasonal changes of soil CO2.efflux, to separate the respective contributions of root and microbial respiration to the total soil CO2.efttux, and to determine the environmental factors that control soil respiration. Minimal microbial respiration rate was estimated based on the linear regression equations between soil CO2.effiux and root mass at different experimental sites. Soil CO2.efflux, ranging from 4.99 to 16.2. μmol CO2.m^-2.s^-1, depended on the seasonal changes in soil temperature. The root mass at 0-10 cm soil depth was 0.82.and 1.2. kg m^-2.in Apr. and Sep., respectively. The root mass at 0-10 cm soil depth comprised 60% of the total root mass at 0-50 cm soil depth. The root productivity at 0-3. cm depth varied from 8 to 180 g m^-2.month^-1. Microbial and root respiration rates ranged from 1.3. to 5.51 and 2.72.to 12.06μmol CO2.m^-2.s^-1, respectively. The contribution of root respiration to the total soil CO2.efflux averaged 53., ranging from 3.% to 72.. The microbial respiration rate was exponentially related to soil temperature at 10 cm depth （R^2.= 0.9400, P = 0.002. n = 6）, and the root respiration rate was linearly related to the root production at 0-3. cm depth （R2.= 0.6561, P = 0.042. n = 6）.

关键词： grasslands microbial respiration root production root respiration

Sodium fluorescence Doppler lidar to measure atmospheric temperature in the mesopause region

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Science Bulletin 2011年第Z1期 417-423页

作者： HU Xiong1,YAN ZhaoAi1,2.GUO ShangYong1,CHENG YongQiang1 & GONG JianCun1 1 Center for Space Science and Applied Research,chinese academy of {2.,beijing 100190,china 2.Graduate University of chinese academy of sciences,beijing 100049,china

A sodium fluorescence Doppler lidar system has been developed to measure environmental parameters of the middle and upper atmosphere. The lidar system mainly comprises a transmitter system,receiver system,data acquisition and control system and data analysis system. A narrowband 589 nm laser is used to excite sodium atoms in the mesopause region. Excitation of the sodium atoms results in resonance fluorescence,which is collected by the receiver. The temperatures in the mesopause region(about 75-105 km) can be derived by analyzing the Doppler-broadened width of the sodium fluorescence. Observations were made with the lidar system,and the number density of sodium atoms and atmospheric temperature profiles were extracted from the observation data. Comparisons of the lidar temperatures and TIMED/SABER temperatures show good agreement,illustrating the reliability of the sodium fluorescence Doppler lidar measurements.

关键词： Doppler lidar sodium resonance fluorescence mesospause temperature