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Observation results of relativistic electrons detected by Fengyun-1 satellite and analysis of relativistic electron enhancement (REE) events

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Science china(Physics,mechanics & Astronomy) 2008年第12期51卷 1947-1956页

作者： YANG XiaoChao1,2↑ & WANG ShiJin1 1 center for Space Science and Applied Research, chinese academy of sciences, Beijing 100190, china 2 Graduate University of chinese academy of sciences, Beijing 100049, china 1. center for Space Science and Applied Research Chinese Academy of Sciences Beijing 100190 China 2. Graduate University of chinese academy of sciences Beijing 100049 China

The space particle component detector on Fengyun-1 satellite which works at the sun-synchronous orbit of about 870 km altitude has detected relativistic electrons for a long time. In comparison with the SAMPEX satellite observations during 1999–2004, the relativistic electron data from Fengyun-1 satellite from June 1999 to 2005 are used to analyze the relativistic electron enhancement (REE) events at the low earth orbit, and the possible correlation among REE events at the low earth orbit, high-speed solar wind and geomagnetic storms is discussed. The statistical result presents that 45 REE events are found in total during this time period, and the strong REE events with the maximum daily average flux > 400 cm?2·srt-1·s?1 occur mostly during the transition period from solar maximum to solar minimum. Among these 45 REE events, four strong REE events last a longer time period from 26-to 51-day and correlate closely with high speed solar wind and strong geomagnetic storms. Meanwhile, several strong geomagnetic storms occur continuously before these REE events, and these continuous geomagnetic storms would be an important factor causing these long-lasting strong REE events. The correlation analysis for overall 45 events indicates that the strength of the REE events correlates with the solar wind speed and the strength of the geomagnetic storm, and the correlation for strong REE events is much stronger than that for weak REE events.

关键词： relativistic electron enhancement low earth orbit high-speed solar wind geomagnetic storm

Report on Cardiovascular Health and Diseases in china 2023.An Updated Summary

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Biomedical and Environmental sciences 2024年第9期37卷 949-992页

作者： National center for Cardiovascular Diseases The Writing Committee of the Report on Cardiovascular Health and Diseases in china Shengshou Hu .

Since 1990,china has made considerable progress in resolving the problem of“treatment difficulty”of cardiovascular diseases(CVD).The prevalent unhealthy lifestyle among chinese residents has exposed a massive proportion of the population to CVD risk factors,and this situation is further worsened due to the accelerated aging population in *** remains one of the greatest threats to the health of chinese *** terms of the proportions of disease mortality among urban and rural residents in{3.,CVD has persistently ranked *** 2021,CVD accounted for 48.98%and 47.3.%of deaths in rural and urban areas,*** out of every five deaths can be attributed to *** implement a national policy“focusing on the primary health institute and emphasizing prevention”and truly achieve a shift of CVD prevention and treatment from hospitals to communities,the National center for Cardiovascular Diseases has organized experts from relevant fields across{3. to compile the“Report on Cardiovascular Health and Diseases in{3.”annually since *** 2024 report is established based on representative,published,and high-quality big-data research results from cross-sectional and cohort population epidemiological surveys,randomized controlled clinical trials,large sample registry studies,and typical community prevention and treatment cases,along with data from some projects undertaken by the National center for Cardiovascular *** firsthand data not only enrich the content of the current report but also provide a more timely and comprehensive reflection of the status of CVD prevention and treatment in{3..

关键词： Cardiovascular disease Risk factor Prevalence Mortality Rehabilitation Basic research Medical device development Health economics

BRST quantization and canonical Ward identity of the supersymmetric electromagnetic interaction system

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Science china(Physics,mechanics & Astronomy) 2007年第3期50卷 339-347页

作者： HUANG YongChang1,3.4, JIANG YunGuo1 & LI XinGuo2,3.1 institute of Theoretical Physics, College of Applied sciences, Beijing University of Technology, Beijing 100022, china 2 institute of Modern Physics, chinese academy of sciences, Lanzhou 73.000, china 3.center of Theoretical Nuclear Physics, National Laboratory of Heavy Ion Collisions, chinese academy of sciences, Lanzhou 73.000, china 4 china center of Advanced Science and Technology (World Laboratory), Beijing 100080, china 1. institute of Theoretical Physics College of Applied Sciences Beijing University of Technology Beijing 100022 China 3. center of Theoretical Nuclear Physics National Laboratory of Heavy Ion Collisions Chinese Academy of Sciences Lanzhou 730000 China 4. china center of Advanced Science and Technology (World Laboratory) Beijing 100080 China 2. institute of Modern Physics Chinese Academy of Sciences Lanzhou 730000 China

According to the method of path integral quantization for the canonical constrained system in Becchi-Rouet-Stora-Tyutin scheme, the supersymmetric electromagnetic interaction system was quantized. Both the Hamiltonian of the supersymmetric electromagnetic interaction system in phase space and the quantization procedure were simplified. The BRST generator was constructed, and the BRST transforma- tions of supersymmetric fields were gotten; the effective action was calculated, and the generating functional for the Green function was achieved; also, the gauge generator was constructed, and the gauge transformation of the system was ob- tained. Finally, the Ward-Takahashi identities based on the canonical Noether theorem were calculated, and two relations between proper vertices and propaga- tors were obtained.

关键词： supersymmetric electromagnetic interaction BRST quantization Ward identity

Research of the Gas-solid Flow Character Based on the DEM Method

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Journal of Thermal Science 2011年第6期20卷 521-526页

作者： Xueyao Wang and Yunhan Xiao Research center for Clean Energy and Power,chinese academy of{3. Key Laboratory of Advanced Energy and Power,chinese academy of{3. (institute of Engineering Thermophysics),Beijing,100190,china Research center for Clean Energy and Power Chinese Academy of Sciences Beijing China Key Laboratory of Advanced Energy and Power Chinese Academy of Sciences (Institute of Engineering Thermophysics) Beijing China

Numerical simulation of gas-solid flow behaviors in a rectangular fluidized bed is carried out three dimensionally by the discrete element method (DEM).Euler method and Lagrange method are employed to deal with the gas phase and solid phase *** collided force among particles,striking force between particle and wall,drag force,gravity,Magnus lift force and Saffman lift force are considered when establishing the mathematic ***-sphere model is used to describe the collision of *** addition,the Euler method is also used for modeling the solid phase to compare with the results of *** flow patterns,particle mean velocities,particles' diffusion and pressure drop of the bed under typical operating conditions are *** results show that the DEM method can describe the detailed information among particles,while the Euler-Euler method cannot capture the micro-scale *** matter which method is used,the diffusion of particles increases with the increase of gas *** the gathering and crushing of particles cannot be simulated,so the energy loss of particles' collision cannot be calculated and the diffusion by using the Euler-Euler method is *** addition,it is shown by DEM method,with strengthening of the carrying capacity,more and more particles can be schlepped upward and the dense suspension upflow pattern can be ***,the results given by the Euler-Euler method are not consistent with the real situation.

关键词： DEM gas-solid flow numerical simulation

Progress in the detection of human genome structural variations

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Science china(Life sciences) 2009年第6期52卷 560-567页

作者： WU XueMei1,3.& XIAO HuaSheng1,2 1 center of Functional Genomics,Key Laboratory of System Biology,Shanghai institutes for Biological sciences,{3. academy of sciences,Shanghai 20003.,china 2 National Engineering center for Biochip at Shanghai,Shanghai 201203.china 3.Graduate School of the chinese academy of sciences,Shanghai 20003.,china 1. center of Functional Genomics Key Laboratory of System Biology Shanghai Institutes for Biological Sciences Chinese Academy of Sciences Shanghai 200031 China 3. Graduate School of the chinese academy of sciences Shanghai 200031 China 2. National Engineering center for Biochip at Shanghai Shanghai 201203 China

The emerging of high-throughput and high-resolution genomic technologies led to the detection of submicroscopic variants ranging from 1 kb to 3.Mb in the human *** variants include copy number variations(CNVs),inversions,insertions,deletions and other complex rearrangements of DNA *** paper briefly reviews the commonly used technologies to discover both genomic structural variants and their potential ***,we highlight the array-based,PCR-based and sequencing-based assays,including array-based comparative genomic hybridization(aCGH),representational oligonucleotide microarray analysis(ROMA),multiplex amplifiable probe hybridization(MAPH),multiplex ligation-dependent probe amplification(MLPA),paired-end mapping(PEM),and next-generation DNA sequencing ***,we discuss the limitations and challenges of current assays and give advices on how to make the database of genomic variations more reliable.

关键词： structural variation cytogenetic microarray PCR paired end mapping(PEM) next-generation sequencing

Possible mechanism of the effect of convection over Asian-Australian “land bridge” on the East Asian summer monsoon onset

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Science china Earth sciences 2006年第11期49卷 1223-1232页

作者： HE Jinhai1, WEN Min2, DING Yihui3.& ZHANG Renhe2 1. Jiangsu Key Laboratory of Meteorological Disaster (KLME), Nanjing institute of Meteorology, Nanjing University of Informa- tion Science and Technology, Nanjing 210044, china 2. State Key Laboratory of Severe Weather (LaSW), chinese{3. of Meteorological sciences, Beijing 100081, china 3. National Climate center, chinese Meteorological Administration, Beijing 100081, china 1. Jiangsu Key Laboratory of Meteorological Disaster (KLME) Nanjing Institute of Meteorology Nanjing University of Information Science and Technology Nanjing 210044 China 2. State Key Laboratory of Severe Weather (LaSW) Chinese Academy of Meteorological Sciences Beijing 100081 China 3. National Climate center Chinese Meteorological Administration Beijing 100081 China

The Asian-Australian “land bridge” is an area with the most vigorous convection in Asian monsoon region in boreal spring, where the onset and march of convection are well associated with the onset of East Asian summer monsoon. The convection occurs over Indo-china Peninsula as early as mid-April, which exerts critical impact on the evolution of monsoon circulation. Before mid-April there are primarily sensible heatings to the atmosphere over Indo-china Peninsula and Indian Peninsula, so the apparent heating ratios over them decrease with height. However, after mid-April it changes into latent heating over Indo-china Peninsula due to the onset of convection, and the apparent heating ratio increases with height in mid- and lower troposphere. The vertical distribution of heating ratio and its differences between Indo-china Peninsula and Indian Peninsula are the key factors leading to the splitting of boreal subtropical high belt over the Bay of Bengal. Such mechanism is strongly supported by the fact that the evolution of the vertical heating ratio gradient above Indo-china Peninsula leads that of 850 hPa vorticity over the Bay of Bengal. Convections over Indo-china Peninsula and its surrounding areas further increase after the splitting. Since then, there is a positive feedback lying among the convective heating, the eastward retreat of the subtropical high and the march of monsoon, which is a possible mechanism of the advance of summer monsoon and convection from Indo-china Peninsula to South china Sea.

关键词： Asian-Australian 'land bridge', tropical convection, Indo-china Peninsula, the splitting of boreal subtropical high belt, East Asian summer monsoon onset.

Sea-salt aerosol transport patterns over the Northern Hemisphere inferred from two subarctic ice core records

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Science china Earth sciences 2005年第4期48卷 576-584页

作者： YAN Yuping1,2, KANG Shichang2,3.5, SUN Junying4,5, Paul A. Mayewski2 & QIN Dahe5 1. National Climate center, china Meteorological Administration, Beijing 100081, china 2. Climate Change{3., University of Maine, Orono, ME 04469, USA 3.{3. of Tibetan Plateau Research, chinese academy of sciences, Beijing 100085, china 4. chinese academy of Meteorological sciences, Beijing 100081, china 5. Key Laboratory of Ice Core and Cold Regions Environment, Cold and Arid Environmental and Engineering Research{3., chinese academy of sciences, Lanzhou 73.000, china 1. National Climate center China Meteorological Administration 100081 Beijing China 2. Climate Change institute University of Maine 04469 Orono ME USA 3. institute of Tibetan Plateau Research Chinese Academy of Sciences 100085 Beijing China 4. Key Laboratory of Ice Core and Cold Regions Environment Cold and Arid Environmental and Engineering Research Institute Chinese Academy of Sciences 730000 Lanzhou China 5. chinese academy of Meteorological sciences 100081 Beijing China

Atmospheric circulation reconstruction based on glaciochemical records requires knowledge of chemical concentration controls, such as source, transport pathway and strength. To gain insight into these processes, the relationships between glaciochemical records from two Northern Hemisphere sites (Mt. Logan in Yukon Territory and 20D in southern Greenland) and instrumental sea level pressure (SLP) series are investigated. Calibrations between Mt. Logan sea-salt sodium (ssNa+) concentration and SLP series show that ssNa+ concentrations are closely correlated with the autumntime (SON) Aleutian Low and the summertime (JJA) North Pacific Subtropical High. Both the deepened Aleutian Low and enhanced North Pacific Sub- tropical High strengthen the transport of sea-salt aerosols from the North Pacific to the Mt. Logan region. Calibrations between 20D ssNa+ concentrations and SLP series indicate that ssNa+ concentrations are closely related to the wintertime (Jan.) Icelandic Low. A deepening of the Icelandic Low strengthens winter storms and frequent cyclogenesis over the North Atlantic and pushes more sea-salt laden air masses to the Greenland ice sheet. Therefore, ice core ssNa+ records from the Mt. Logan region can be considered as a proxy for reconstructing the au- tumntime Aleutian Low and summertime North Pacific Subtropical High, and the ssNa+ records from Greenland ice core (20D) may provide a proxy for reconstructing the wintertime Icelandic Low.

关键词： sea-salt aerosol, ice core records, sea level pressure, subarctic regions.

Modeling the climate effects of different subregional uplifts within the Himalaya-Tibetan Plateau on Asian summer monsoon evolution

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chinese Science Bulletin 2012年第35期57卷 4617-4626页

作者： ZHANG Ran 1,JIANG DaBang 1,2,3.LIU XiaoDong 4 & TIAN ZhiPing 2,5 1 Climate Change Research center,chinese academy of{3.,Beijing 100029,china 2 Nansen-Zhu International Research Centre,institute of Atmospheric Physics,chinese academy of{3.,Beijing 100029,china 3.Key Laboratory of Regional Climate-Environment Research for Temperate East Asia,chinese academy of{3.,Beijing 100029,china 4 State Key Laboratory of Loess and Quaternary Geology,institute of Earth Environment,chinese academy of{3.,Xi’an 710075,china 5 Graduate University of chinese academy of sciences,Beijing 100049,china 1. Climate Change Research center Chinese Academy of Sciences Beijing 100029 China 2. Nansen-Zhu International Research Centre Institute of Atmospheric Physics Chinese Academy of Sciences Beijing 100029 China 3. Key Laboratory of Regional Climate-Environment Research for Temperate East Asia Chinese Academy of Sciences Beijing 100029 China 4. State Key Laboratory of Loess and Quaternary Geology Institute of Earth Environment Chinese Academy of Sciences Xi’an 710075 China 5. Graduate University of chinese academy of sciences Beijing 100049 China

Considering the different uplifting time of different subregions of the Himalaya-Tibetan Plateau(TP),a series of numerical simulations have been conducted with the Community Atmosphere Model(CAM4) developed at the National center for Atmospheric Research to explore the effects of the phased tectonic uplift of the Himalaya-TP on the evolution of Asian summer *** results show that the uplifts of the Himalaya and northern TP significantly affect the evolutions of South Asian summer monsoon and northern East Asian summer monsoon *** is,the tectonic uplift of the Himalaya intensifies the South Asian summer monsoon circulation and increases the precipitation in South Asia,whereas the uplift of the northern TP intensifies the northern East Asian summer monsoon circulation and increases the precipitation in northern East *** with previous simulations,current comparative analyses of modeling results for different subregional uplifts within the Himalaya-TP help deepen our understanding of the evolutionary history of Asian monsoons.

关键词：青藏高原隆升喜马拉雅亚洲季风高原气候夏季季风次区域隆起演化建模

Functional analysis of schistosomes EF-hand domain-containing tegument proteins

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chinese Science Bulletin 2007年第15期52卷 2100-2107页

作者： YU FuDong1,2,3.KANG Bin1,3.LI YuanYuan3.4 & LI YiXue1,3.1 Bioinformatics center,Key Laboratory of Systems Biology,Shanghai institutes for Biological sciences,{3. academy of Sci-ences,Shanghai 20003.,china 2 Graduate University of chinese academy of sciences,Shanghai 20003.,china 3.Shanghai center for Bioinformation Technology,Shanghai 20023.,china 4 Key Laboratory of Systems Biology,Shanghai institutes for Biological sciences,{3. academy of sciences,Shanghai 20003.,china Bioinformatics center Key Laboratory of Systems Biology Shanghai Institutesfor Biological Sciences Chinese Academy of Sciences Shanghai 200031 China

Schistosomes cause schistosomiasis disease which severely threatens human health. Little is known about the functions of EF-hand domain containing schistosomes tegument proteins other than as an-tigens. More possible functions of these tegument proteins were investigated with in silico analyses including protein-protein functional interaction,site-specific variation and glycosylation modification. The analysis results suggested that schistosomes could actively modulate host immune responses for its own favor through functional interactions with host proteins with immunomodulatory function,and passively regulate host immune responses through sequence variation under positive selection and glycosylating the recognition sites of host immune attack. In addition,the analysis of the C-terminal domain of these tegument proteins indicated that they could assist schistosomes in escaping host immune attacks through inhibiting chemotaxis and non-complement fixing antibody (IgG4) responses. In summary,our results suggested that these tegument antigen proteins could assist schistosomes in escaping and modulating host immune responses for self-protection during the process of host-para-site interaction.

关键词：寄生虫血吸虫皮蛋白质健康