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Characterization of GLUT4-containing vesicles in 3T3-L1 adipocytes by total internal reflection fluorescence microscopy

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Science china(Life sciences) 2009年第7期52卷 665-671页

作者： WANG Yan1,2.ZHANG JinZhong1,2.CHEN Yu1,2.JIANG Li1,2.JI Wei1,2.& XU Tao1 1 National Laboratory of Biomacromolecules,Institute of Biophysics,chinese academy of {2.,Beijing 100101,china 2.graduate University of chinese academy of sciences,Beijing 100049,china 1. National Laboratory of Biomacromolecules Institute of Biophysics Chinese Academy of Sciences Beijing 100101 China 2. graduate University of chinese academy of sciences Beijing 100049 China

Insulin-responsive GLUT4(glucose transporter 4) translocation plays a major role in regulating glucose uptake in adipose tissue and *** or not there is a specialized secretory GSV(GLUT4 storage vesicle) pool,and more importantly how GSVs are translocated to the PM(plasma membrane) under insulin stimulation is still under *** the present study,we systematically analyzed the dynamics of a large number of single GLUT4-containing vesicles in 3T3-L1 adipocytes by TIRFM(total internal reflection fluorescence microscopy).We found that GLUT4-containing vesicles can be classified into three groups according to their mobility,namely vertical,stable,and lateral GLUT4-containing *** these groups,vertical GLUT4-containing vesicles exclude transferrin receptors and move towards the PM specifically in response to insulin stimulation,while stable and lateral GLUT4-containing vesicles contain transferrin receptors and show no insulin *** data demonstrate that vertical GLUT4-containing vesicles correspond to specialized secretory GSVs,which approach the PM directly and bypass the constitutive recycling pathway.

关键词： GLUT4 IRAP-pHluorin GSV transferring TIRFM

Exsolution of ilmenite and Cr-Ti magnetite from olivine of garnet-wehrlite

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Science china Earth sciences 2005年第9期48卷 1368-1376页

作者： LIU Xiangwen1,2. JIN Zhenmin1,3, QU Jing2.& WANG Lu2.1. State Key Laboratory of Geological Processes and Mineral Resources, china University of Geosciences, Wuhan 430074, china 2. graduate school of china University of Geosciences, Wuhan 430074, china 3. Faculty of Earth sciences, china University of Geosciences, Wuhan 430074, china 1. State Key Laboratory of Geological Processes and Mineral Resources China University of Geosciences 430074 Wuhan China 2. graduate school of china University of Geo{2. 430074 Wuhan China 3. Faculty of Earth sciences China University of Geosciences 430074 Wuhan China

Exsolution of rod-like ilmenite (Ilm) and Cr-Ti magnetite (Mt) have been found in olivine of garnet-wehrlite from the core of chinese Continental sciences Drilling (CCSD). Their composition, morphology, crystal structure and their topotaxies with host olivine have been studied in detail by the transmission electron microscopy (TEM) and electron probe microanaly- sis (EPMA) technique. It shows that rod-like Ilm exsolution reported in this paper has similar characteristic with that of Alpe Arami olivine, while Cr-Ti magnetite exsolution mentioned in this paper has large discrepancy with chromite exsolution in Alpe Arami olivine. These observations suggest that both of the exsolutions found in this paper should be solid solution phases in β-olivine at their first period, then experiencing decomposition of solid solution and therefore forming Ilm and Cr-Ti magnetite exsolution with the pressure decreasing. So, this garnet-wehrlite perhaps had been ever located in mantle transition zone with a minimum depth of 300 km.

关键词： garnet-wehrlite, ilmenite, magnetite, exsolution, CCSD.

Monitoring the Cultivated Slope Land in the Three Gorges Reservoir Area Based on Remote Sensing and GIS

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Wuhan University Journal of Natural sciences 2006年第4期11卷 915-921页

作者： ZHOU Jieming1, ZHOU Qigang 2. 3 ,HUANG Zhiqin 2. 3, 4 1. The Faculty of Geography and Resources Science, Sichuan Normal University, Chengdu 610066, Sichuan, china 2. Institute of Mountain Hazards and Environment, chinese academy of sciences, Chengdu 610041, Sichuan, china 3. graduate University of the chinese academy of sciences, Beijing 100049, china 4. Information Center of Land and Resources Department of Sichuan Province, Chengdu 610041, Sichuan, china The Faculty of Geography Resources Science Sichuan Normal University 610066 Chengdu Sichuan China Institute of Mountain Hazards Environment Chinese Academy of Sciences 610041 Chengdu Sichuan China graduate University of the chinese academy of sciences 100049 Beijing China Information Center of Land Resources Department of Sichuan Province 610041 Chengdu Sichuan China

By means of combining auto-extraction with manual interpretation, the current distribution information about cultivated land is obtained. The distribution information of 1992.is extracted from the dynamic polygons of 2.02. The monitoring mini-system of the cultivated slope land is established. In the system, detailed surveys, focused on the resources of cultivated slope land, are carried out. The results indicate that the area of the cultivated slope land is very large. Meanwhile, there are lots of cultivated steep slopes with gradient above 35°. The areas of steep land cultivated had been slowly reduced from 1992.to 2.02. At the same time, the pressures of returning farm land to forestry are great in all counties. The conflicts between population growth, insufficient grain supply and stagnant economic development sharpen increasingly. It is inevitable to improve the agricultural structure.

关键词： slope land cultivated remote sensing geography information system (GIS) the pressure of returning farm land to forestry Three Gorges Reservoir Area

Contributions of phosphatase and microbial activity to internal phosphorus loading and their relation to lake eutrophication

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Science china Earth sciences 2006年第z1期49卷 102-113页

作者： SONG Chunlei, CAO Xiuyun, LI Jianqiu, LI Qingman, CHEN Guoyuan & ZHOU Yiyong Institute of Hydrobiology, chinese academy of sciences, Wuhan 430072. china {2. school of the chinese academy of sciences, Beijing 100039, china 1. Institute of Hydrobiology Chinese Academy of Sciences Wuhan 430072 China 2. graduate school of the chinese academy of sciences Beijing 100039 China

Phosphatase may accelerate the process of lake eutrophication through improving phosphorus bioavailability. This mechanism was studied in three chinese eutrophic shallow lakes (Lake Taihu, Lake Longyang and Lake Lianhua). Phosphatase activity was related to the concentration of soluble reactive phosphorus (SRP) and chlorophyll a. Stability of dissolved phosphatase in reverse micelles may be attributed to molecular size, conformation and active residues of the *** the site with Microcystis bloomed in Lake Taihu, dissolved phosphatase activity was higher and more stable in micelles, SRP concentrations were lower in interstitial water, the contents of different forms of phosphorus and the amounts of aerobic bacteria were lower while respiration efficiency was higher in sediments. Phosphobacteria, both inorganic and organic and other microorganisms were abundant in surface water but rare in sediments. Therefore, internal phosphorus may substantially flux into water column by enzymatic hydrolysis and anaerobic release, together with mobility of bacteria,thereby initiating the bloom. In short, biological mechanism may act in concert with physical and chemical factors to drive the internal phosphorus release and accelerate lake eutrophication.

关键词： dissolved phosphatase, reverse micelle, internal loading, phosphorus form of sediment, microbiology, eutrophication, Microcystis bloom.

Improving the accuracy of image-based forest fire recognition and spatial positioning

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Science china(Technological sciences) 2010年第S1期53卷 184-190页

作者： JIANG LiLi 1,QI QingWen 1,ZHANG An 1,GUO ChaoHui 2.& CHENG Xi 1,3 1 Institute of Geographical sciences and Natural Resources Research,chinese {2. of sciences,Beijing 100101,china 2.5} Center for Resources Satellite Data and Applications,Beijing 100094,china 3graduate University of chinese academy of sciences,Beijing 100049,china chinese Acad Sci Inst Geog Sci & Nat Resources Res Beijing 100101 Peoples R China china Ctr Resources Satellite Data & Applicat Beijing 100094 Peoples R China chinese Acad Sci Grad Univ Beijing 100049 Peoples R China

Forest fires are frequent natural *** is necessary to explore advanced means to monitor,recognize and locate forest fires so as to establish a scientific system for the early detection,real-time positioning and quick fighting of forest *** paper mainly expounds methods and algorithms for improving accuracy and removing uncertainty in image-based forest fire recognition and spatial ***,we discuss a method of forest fire recognition in visible-light *** are four aspects to improve accuracy and remove uncertainty in fire recognition:(1)eliminating factors of interference such as road and sky with high brightness,red leaves,other colored objects and objects that are lit up at night,(2.excluding imaging for specific periods and azimuth angles for which interference phenomena repeatedly occur,(3)improving the thresholding method for determining the flame border in image processing by adjusting the threshold to the season,weather and region,and (4)integrating the visible-light image method with infrared image ***,we examine infrared-image-based methods and approaches of improving the accuracy of forest fire recognition by combining the spectrum threshold with an object feature value such as the normalized difference vegetation index and excluding factors of disturbance such as interference signals,extreme weather and high-temperature ***,a method of visible analysis to enhance the accuracy of forest fire positioning is examined and realized;the method includes decreasing the visual angle,selecting central points,selecting the largest spots,and judging the selection of fire spots according to the central *** studies are examined and the results are found to be satisfactory.

关键词： forest fire monitoring spatial positioning accuracy improvement

The Impacts of Permafrost Change on NPP and Implications:A Case of the Source Regions of Yangtze and Yellow Rivers

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Journal of Mountain Science 2011年第3期8卷 437-447页

作者： FANG Yiping QIN Dahe DING Yongjian YANG Jianping XU Keyan Institute of Mountain Hazards & Environment Chinese Academy of Sciences Chengdu 610041 China Cold and Arid Regions Environmental and Engineering Research Institute Chinese Academy of Sciences Lanzhou 730000 China graduate school of{2. Beijing 100049 China

This paper studies the relationship between net primary productivity (NPP) and annual average air temperature (GT) at 0cm above ground in permafrost regions by using revised Chikugo NPP model,cubic spline interpolating functions,and non-linear regression *** source regions of the Yangtze and Yellow Rivers were selected as the research *** illustrate that:(1) There is significant non-linear relationship between NPP and GT in various typical years;(2. The maximum value of NPP is 6.17,5.87,7.73,and 5.41 DM·t·hm-2.·a-1 respectively,and the corresponding GT is 7.1,10.0,2..2.and 8.9 o C respectively in 1980,1990,2.00 and 2.07;(3) In 1980,the sensitivity of NPP to GT is higher than in 1990,2.00 and *** tendency shows that the NPP presents change from fluctuation to an adaptation process over time;(4) During 1980～2.07,the accumulated NPP was reduced to 8.05,and the corresponding carrying capacity of theoretical livestock reduced by 11%;(5) The shape of the demonstration region of ecological compensation system,livelihood support system,and science appraisal system in the source regions of Yangtze and Yellow Rivers are an important research for increasing the adaptation capacity and balancing protection and development.

关键词： The source regions of Yangtze and Yellow Rivers Permafrost Ground temperature (GT) Net primary productivity (NPP) Policy adaptation

Enzymatic cyclization of linear peptide to plant cyclopeptide heterophyllin B

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Science china Chemistry 2006年第1期49卷 63-66页

作者： JIA Aiqun1, LI Xiang2. TAN Ninghua1, LIU Xiaozhu3, SHEN Yuemao1 & ZHOU Jun1 1. State Key Laboratory of Phytochemistry and Plant Resources in West china, Kunming Institute of Botany, graduate Univer-sity of{2.,{2., Kunming 6502.4, china 2. chinese Peptide Co., Ltd, Hangzhou 310018, china 3. Southwest Forestry College, Kunming 6502.4, china 1. State Key Laboratory of Phytochemistry and Plant Resources in West china Kunming Institute of Botany Graduate University of Chinese Academy of Sciences Chinese Academy of Sciences Kunming 650204 China 2. chinese Peptide Co. Ltd Hangzhou 310018 China 3. Southwest Forestry College 650204 Kunming China

The crude enzyme (PH-1) isolated from Pseudostellaria heterophylla by ourgroup has catalyzed enzymatic cyclization of linear peptideNH_2.Gly^1-Gly^2.Leu-Pro-Pro-Pro-lle-Phe-COOH (4) into cyclopeptide heterophyllin B (HB) from plantfor the first time. To ensure this reaction, some analytical methods including TLC, HPLC, MS, NMR,and ^(13)C labeling were used to prove that the reaction of substrate 4 sharing residue ofNH-Phe-Gly-CO was successful.

关键词： Pseudostellaria heterophylla, cyclopeptides, HB, enzymatic cyclization, isotope labeled.

A one-dimensional heat transfer model of the Antarctic Ice Sheet and modeling of snow temperatures at Dome A, the summit of Antarctic Plateau

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Science china Earth sciences 2010年第5期53卷 763-772页

作者： CHEN BaiLian1,3, ZHANG RenHe2. SUN ShuFen1, BIAN LinGen2. XIAO CunDe4,2.& ZHANG TingJun5 1 Institute of Atmospheric Physics, chinese academy of sciences, Beijing 10002., china 2.{2. academy of Meteorological sciences, Beijing 100081, china 3 graduate University of chinese academy of sciences, Beijing 100049, china 4 Cold and Arid Regions Environmental and Engineering Research Institute, chinese academy of sciences, Lanzhou 730000, china 5 The National Snow and Ice Data Center, University of Colorado, Boulder, CO 80309-0449, USA 1. Institute of Atmospheric Physics Chinese Academy of Sciences Beijing 100029 China3. Graduate University of Chinese Academy of Sciences Beijing 100049 China2. Chinese Academy of Meteorological Sciences Beijing 100081 China4. Cold and Arid Regions Environmental and Engineering Research Institute Chinese Academy of Sciences Lanzhou 730000 China5. The National Snow and Ice Data Center University of Colorado Boulder CO 80309-0449 USA

A vertical one-dimensional numerical model for heat transferring within the near-surface snow layer of the Antarctic Ice Sheet was developed based on simplified parameterizations of associated physical processes for the atmosphere, radiation, and snow/ice systems. Using the meteorological data of an automatic weather station (AWS) at Dome A (80°2.′S, 70°2.′E), we applied the model to simulate the seasonal temperature variation within a depth of 2. m. Comparison of modeled results with observed snow temperatures at 4 measurement depths (0.1, 1, 3, 10 m) shows good agreement and consistent seasonal variations. The model results reveal the vertical temperature structure within the near-surface snow layer and its seasonal variance with more details than those by limited measurements. Analyses on the model outputs of the surface energy fluxes show that: 1) the surface energy balance at Dome A is characterized by the compensation between negative net radiation and the positive sensible fluxes, and 2. the sensible heat is on average transported from the atmosphere to the snow, and has an evident increase in spring. The results are considered well representative for the highest interior Antarctic Plateau.

关键词： Antarctic Ice Sheet near-surface layer energy transfer numerical model

Early scale effect and hemisphere superiority on the visual spatial attention:From the electrophysiological evidence of ERP

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Progress in Natural Science:Materials International 2004年第10期14卷 35-39页

作者： SONG Weiqun 1,3 ,GAO Yuan 1 and LUO Yuejia 1,2. (1.Key Laboratory of Mental Health,Institute of Psychology,chinese academy of {2.,Beijing100101,china 2.school of Psy-chology,Southwest china Normal University,Chongqing400715,china 3.graduate school of the chinese academy of sciences,Bei-jing100039,china) chinese Acad Sci Inst Psychol Key Lab Mental Hlth Beijing 100101 Peoples R China SW china Normal Univ Sch Psychol Chongqing 400715 Peoples R China chinese Acad Sci Grad Sch Beijing 100039 Peoples R China

The visual attention mechanism in the brain was studied among16young subjects through the precue-target visual search paradigm using the event-related potentials(ERPs)technique,with the attentive ranges cued with different scales of chinese *** results showed that the response time was shortened as the cue scale was reduced,while the amplitudes of the P1and N1components of the ERPs *** results not only provided the electrophysiological evidence supporting the spotlight theory,but also indicated that the spotlight effect occurred during the early period of the selected *** kinds of separation in the P2.ffect were *** separation was between the P1effect and P2.ffect,which meant that additional computation was needed when the spatial scale of attention was enlarged;the other was between the left and right hemisphere of the P2.ffect,which indicates that the at-tentive processing of the cue range mainly occurred in the left hemisphere.

关键词： visual spatial attention cue scale spotlight effect hemisphere superiority event-related potential(ERP)