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1Reconstruction of precipitation variation from tree rings in recent 1000 years in Delingha, Qinghai显示文摘Using seven well-replicated Qilian juniper (Sabina przewalskii Kom.) ring-width chronologies developed at Zongwulong and Shalike Mts. in the northeastern part of the Qaidam Basin annual precipitation from previous July to current June in the recent 1000 years was re- constructed for Delingha. The reconstruction can capture 63.1% of precipitation variance and the equation was stable over time. For the reconstructed precipitation, wet periods occurred in AD1520—1633 and 1933—2001, whereas dry intervals in 1429—1519 and 1634—1741. In ad- dition, the magnitude in precipitation variation was lower before 1430 with about 15 mm, but it increased to 30 mm during the period of 1430 to 1850. After 1850, the precipitation variance de- creased again. In contrast to the increase in temperature, a decrease in annual precipitation was evident since the 1990s. The agreement in low-frequency variation between the reconstruction and the glacier accumulation and particulate content in Dunde ice cores during the recent several hundred years suggested that the precipitation reconstructed in this study was rather reliable, and represented a regional signal. This 1000-year reconstruction could benefit our understanding of climatic variation in decadal to century-scale in this region, and provide basic data to climate models and to prediction of future climate in the 21st century.SHAO Xuemei1, HUANG Lei1, LIU Hongbin2, LIANG Eryuan1, FANG Xiuqi3 & WANG Lili1 1. Institute of Geographic Sciences and Natural Resources Research, Chinese Academy of Sciences, Beijing 100101, China 2. National Climate Center, Beijing 100081, China 3. Beijing Normal University, Beijing 100875, China 2005Science China Earth Sciences2005,48,7:113
2MAPK signal pathways in the regulation of cell proliferation in mammalian cells显示文摘MAPK families play an important role in complex cellular programs like proliferation, differentiation, development, transformation, and apoptosis. At least three MAPI(families have been characterized: extracellular signal-regulated kinase (ERK), Jun kinase (JNK/SAPK) and p38 MAPK. The above effects are fulfilled by regulation of cell cycle engine and other cell proliferation related proteins. In this paper we discussed their functions and cooperation with other signal pathways in regulation of cell proliferation.WEI ZHANG, Hui Tu LIU The Key Laboratory of Cell Proliferation and Regulation Biology of Ministry of Education, College of Life Sciences, Beijing Normal University, Beijing 100875, China 2002Cell Research2002,12,1:107
3L^p-Boundedness of Marcinkiewicz Integrals with Hardy Space Function KernelsYong Ding Department of Mathematics, Beijing Normal University, Beijing 100875, P. R. China Dashan Fan Department of Mathematics, Anhui University and University of Wisconsin-Milwaukee. MW 53201 USA Yibiao Pan Department of Mathematics, University of Pittsburgh. Pittsburgh. Pennsylvania 15260. USA 2000Acta Mathematica Sinica,English Series2000,16,4:88
4Plausible impact of global climate change on water resources in the Tarim River Basin显示文摘Combining the temperature and precipitation data from 77 climatological stations and the climatic and hydrological change data from three headstreams of the Tarim River: Hotan, Yarkant, and Aksu in the study area, the plausible association between climate change and the variability of water resources in the Tarim River Basin in recent years was investigated, the long-term trend of the hydrological time series including temperature, precipitation, and streamflow was detected, and the possible association between the El Ni(n)o/Southern Oscillation (ENSO) and these three kinds of time series was tested. The results obtained in this study show that during the past years, the temperature experienced a significant monotonic increase at the speed of 5%, nearly 1℃ rise; the precipitation showed a significant decrease in the 1970s, and a significant increase in the1980s and 1990s, the average annual precipitation was increased with the magnitude of 6.8 mm per decade. A step change occurred in both temperature and precipitation time series around 1986, which may be influenced by the global climate change. Climate change resulted in the increase of the streamflow at the headwater of the Tarim River, but the anthropogenic activities such as over-depletion of the surface water resulted in the decrease of the streamflow at the lower reaches of the Tarim River. The study result also showed that there is no significant association between the ENSO and the temperature, precipitation and streamflow.CHEN Yaning & XU Zongxue Xinjiang Institute of Ecology & Geography, Chinese Academy of Sciences, Urumqi 830011, China College of Environmental Sciences, Beijing Normal University, Beijing 100875, China 2005Science China Earth Sciences2005,48,1:56
5Numerical Simulation on Climate Effects of Freezing-Thawing Processes Using CCM3显示文摘A parameterization of soil freezing-thawing physics for use in the land-surface model of the National Center for Atmospheric Research(NCAR) Community Climate Model(CCM3) is developed and evaluated.The new parameterization scheme has improved the representation of physical processes in the existing land surface model.Numerical simulations using CCM3 with improved land-surface processes and with the original land-surface processes are compared against the NCEP reanalysis.It is found that the CCM3 version using the improved land surface model shows significant improvements in simulating precipitation in China during the summer season,the general circulation over East Asia,and wind fields over the Tibet Plateau.For the summer season,the improved model was able to better simulate the Indian summer monsoon components,including the mean northerly wind in the upper troposphere and mean southerly wind in the lower troposphere.Chenghai Wang1,2*,Guodong Cheng3,Aijun Deng4,Wenjie Dong5 1.State Key Laboratory of Frozen Soil Engineering,Cold and Arid Regions Environmental and Engineering Research In-stitute,Chinese Academy of Sciences,Lanzhou Gansu 730000,China 2.State Key Laboratory of Cryosphere Sciences,Cold and Arid Regions Environmental and Engineering Research Insti-tute,Chinese Academy of Sciences,Lanzhou Gansu 730000,China 3.State Key Laboratory of Frozen Soil Engineering,Cold and Arid Regions Environmental and Engineering Research In-stitute,Chinese Academy of Sciences,Lanzhou Gansu 730000,China 4.Department of Meteorology,The Pennsylvania State University,University Park,PA 16802 5.State Key Laboratory of Earth Surface Processes and Ecology Resource,Beijing Normal University,Beijing 100875,China Chenghai Wang1,2*,Guodong Cheng3,Aijun Deng4,Wenjie Dong5 1.State Key Laboratory of Frozen Soil Engineering,Cold and Arid Regions Environmental and Engineering Research In-stitute,Chinese Academy of Sciences,Lanzhou Gansu 730000,China 2.State Key Laboratory of Cryosphere Sciences,Cold and Arid Regions Environmental and Engineering Research Insti-tute,Chinese Academy of Sciences,Lanzhou Gansu 730000,China 3.State Key Laboratory of Frozen Soil Engineering,Cold and Arid Regions Environmental and Engineering Research In-stitute,Chinese Academy of Sciences,Lanzhou Gansu 730000,China 4.Department of Meteorology,The Pennsylvania State University,University Park,PA 16802 5.State Key Laboratory of Earth Surface Processes and Ecology Resource,Beijing Normal University,Beijing 100875,China 2008Research in Cold and Arid Regions2008,,1:44
6Characterization for commutators of n-dimensional fractional Hardy operators显示文摘In this paper, it was proved that the commutator Hβ,b generated by an n-dimensional fractional Hardy operator and a locally integrable function b is bounded from Lp1(Rn) to Lp2 (Rn) if and only if b is a C(M)O(Rn) function, where 1/p1 - 1/p2 = β/n, 1 < p1 <∞, 0 ≤β< n. Furthemore,the characterization of Hβ,b on the homogenous Herz space (K)qα,p(Rn) was obtained.Zun-wei FU~(1,2) Zong-guang LIU~3 Shan-zhen LU~(1+) Hong-bin WANG~3 ~1 School of Mathematical Sciences,Beijing Normal University,Beijing 100875,China ~2 Department of Mathematics,Linyi Normal University,Linyi 276005,China ~3 Department of Mathematics,China University of Mining and Technology (Beijing),Beijing 100083,China 2007Science China Mathematics2007,50,10:39
7大学生抑郁症的心理分析及调控策略显示文摘当前,大学生抑郁症的发病率呈明显上升趋势,已严重影响到大学生的身心健康。大学生抑郁症主要表现在生理和心理两个方面。其诱因既有内因,如生理原因、心理原因、认知原因等,又有外因,如外部压力、人际关系紧张、社会传统观念的影响等。针对这些诱因,文章提出了相应的调控策略,希冀对有效预防大学生心理疾病起到一定的作用。孔凡寅 北京100875 2006高等教育研究(成都)2006,22,2:39
8Weighted weak type estimates for commutators of the Marcinkiewicz integrals显示文摘In this paper the authors give the weighted weak LlogL type estimates for a class of the higher order commutator generated by the Marcinkiewicz integral and a BMO function. In addition, the weak type norm inequalities for the Marcinkiewicz integral and its commutators with different weight functions are also discussed.DING Yong, LU Shanzhen & ZHANG PuDepartment of Mathematics, Beijing Normal University, Beijing 100875, China Department of Information and Computing Science, Zhejiang Institute of Science and Technology, Hangzhou 310033, China 2004Science China Mathematics2004,47,1:25
9Calderón-Zygmund-Type Operators on Weighted Weak Hardy Spaces over R^nTongseng Quek Department of Mathematics,National University of Singapore,Singapore 119260,Republic of SingaporeDachun Yang~* Department of Mathematics,Beijing Normal University,Beijing 100875,P.R.China 2000Acta Mathematica Sinica,English Series2000,16,1:26
10Weighted Boundedness for a Class of Rough Multilinear OperatorsYong DING Shan Zhen LU Department of Mathematics,Beijing Normal University,Beijing 100875,P.R.China E-mail:dingy@bnu.edu.cn lusz@bnu.edn.cn 2001Acta Mathematica Sinica,English Series2001,17,3:24
11Discovery of laryngeal carcinoma by serum proteomic pattern analysis显示文摘Laryngeal carcinoma is the most common malignancy among head and neck tu-mors. The purpose of this study is to find biomarkers for laryngeal carcinoma in patient blood serum using the Surface Enhanced Laser Desorption/Ionization (SELDI) technique. Serum samples from 33 laryngeal carcinoma (12 cases of glottis, 18 of supraglottis and 3 of subglottis) patients and 31 age- and sex-matched healthy people were analyzed by SELDI-TOF on a Pro-teinChip reader, PBSII-C. Protein profiles were generated using WCX2 protein chips. Protein peak clustering and classification analyses were performed utilizing the Biomarker Wizard and Biomarker Pattern software packages, respectively. The results showed that sixteen peaks had significant difference between laryngeal cancer patients and healthy group, eight of which were up-regulated in the patient samples, and the others were down-regulated. Two protein peaks 8153 Da and 2035 Da were automatically chosen for the system training and development of a classification tree. The analysis yielded a correct percentage of 96.9% for patients and 96.7% for control. The results suggest that serum is a useful resource for the detection of specific bio-markers for laryngeal carcinoma. Proteinchip Array System was a useful tool for a high throughput screening of large-sized serum samples to discover potential biomarkers for carci-noma.XIAO Xueyuan1, ZHAO Xiaodong2, LIU Jiankai3, GUO Fuzheng1, LIU Danhui1 & HE Dacheng1 1. Key Laboratory for Cell Proliferation and Regulation Biology, Ministry of Education, Beijing Normal University, Universities?Confeder-ated Institute of Proteomics, Beijing 100875, China 2. Department of Otolaryngology-Head and Neck Surgery, Third Affiliated Hospital, Jilin University, Changchun 130031, China 3. Department of Biochemistry, Jilin University, Changchun 130021, China 2004Science China(Life Sciences)2004,47,3:22
12Parameter determination to calculate water environmental capacity in Zhangweinan Canal Sub-basin in China显示文摘Zhangweinan canal sub-basin (ZWN) has the most serious water resource shortage and water pollution problems in north of China.To calculate the water environmental capacity in ZWN,determination methods for design flow rates and degradation coefficients were discussed in this study.Results showed that 90% and 50% hydrological guarantee flow rates were suitable to be the design flow rates for rainy and dry seasons,respectively.Degradation coefficients of COD Mn and NH 3 -N were 0.25 day -1 and 0.15 day -1 for branch streams and 0.5 day -1 and 0.25 day -1 for mainstreams,respectively in ZWN.With one-dimensional water quality simulation model,water environmental capacities were calculated to be 82,139 tons/yr for COD Mn and 2394 tons/yr for NH 3 -N in ZWN.Yingxia Li ,Ruzhi Qiu,Zhifeng Yang,Chunhui Li,Jingshan Yu State Key Laboratory of Water Environment Simulation,School of Environment,Beijing Normal University,Beijing,100875,China. 2010Journal of Environmental Sciences2010,22,6:23
13Developing land use scenario dynamics model by the integration of system dynamics model and cellular automata model显示文摘Modeling land use scenario changes and its potential impacts on the structure and function of the ecosystem in the typical regions are helpful to understanding the interactive mechanism between land use system and ecological system. A Land Use Scenario Dynamics (LUSD) model by the integration of System Dynamics (SD) model and Cellular Automata (CA) model is developed with land use scenario changes in northern China in the next 20 years simulated in this paper. The basic idea of LUSD model is to simulate the land use scenario de-mands by using SD model at first, then allocate the land use scenario patterns at the local scale with the considerations of land use suitability, inheritance ability and neighborhood effect by using CA model to satisfy the balance between land use scenario demands and supply. The application of LUSD model in northern China suggests that the model has the ability to reflect the complex behavior of land use system at different scales to some extent and is a useful tool for assessing the potential impacts of land use system on ecological system. In addition, the simulated results also indicate that obvious land use changes will take place in the farming-pastoral zone of northern China in the next 20 years with cultivated land and urban land being the most active land use types.HE Chunyang, SHI Peijun, CHEN Jin, Li Xiaobing, PAN Yaozhong, LI Jing, LI Yuechen & LI Jinggang Key Laboratory of Environmental Change and Natural Disaster, Ministry of Education of China, Beijing Normal University College of Resources Science & Technology, Beijing Normal University, Beijing 100875, China 2005Science China Earth Sciences2005,48,11:21
14Monitoring the concentration of N_2O in the Fildes Peninsula, maritime Antarctica显示文摘Gases in the marine boundary layer in Fildes Peninsula, maritime Antarctica were sampled and analyzed for the first time. Sampling sites included areas covered by moss and lichen growth, penguin colonies and an area where scientific research stations are located. A total of 211 samples were analyzed for N2O concentrations, with an average of (321.33±3.07) nL/L. This is above the global average value of 314 nL/L. It is found that the N2O concentrations evidently increase during the summer months. Concentrations around the research stations are higher than at remote areas, indicating a potential source from human activities on the island. N2O concentrations at a large penguin colony on Barton Peninsula are the highest among the sampled areas. This may explain why N2O concentrations in Fildes Peninsula are higher than the global average. Our preliminary conclusions are that human activities and emissions from penguin dropping-amended soil and vegetation soil constitute the major sources of N2O in theSUN Liguang, XIE Zhouqing, ZHAO Junlin, XING Guangxi, SHI Shulian & Du LijuanInstitute of Polar Environment, University of Science and Technology of China, Hefei 230026, China Institute of Environmental Science, Beijing Normal University, Beijing 100875, China Laboratory of Material Cycling in Pedosphere, Institute of Soil Science, Chinese Academy of Sciences, Nanjing 2 10008, China 2000Chinese Science Bulletin2000,45,21:21
15Characteristics of mantle degassing and deep-seated geological structures in different typical fault zones of China显示文摘In this paper a comprehensive tracing study is conducted on mantle degassing and deep-seated geological structures in different types of fault zones in the continent of China based on the helium isotope data, coupled with some indices such as CO2/3He, CH4/3He and 40Ar/36Ar, and geological tectonics data. There are four representative types of fault zones: (1) Lithospheric fault zones in the extensional tectonic environment are characterized by a small Earth’s crust thickness, a lower CH4/3He-high R and lower CO2/3He-high R system, the strongest mantle de- gassing, and the dominance of mantle fluid, as is represented by the Tancheng-Lujiang fault zone. (2) The lithospheric fault zones or the subduction zone in the strongly compresso-tectonic envi- ronment, for instance, the Bangonghu-Nujiang fault zone, are characterized by a huge thick Earth’s crust, with the R/Ra values within the range of 0.43―1.13, and weak mantle degassing with mantle-source helium accounting for 5%―14% of the total. (3) The deep-seated fault zones at the basinal margins of an orogenic belt are characterized by R values being on order of mag- nitude of 10?7, and the CH4/3He values, 109―1010, CO2/3He values, 106―108; as well as much weak mantle degassing. (4) The crustal fault zones in the orogenic belt, such as the Yaojie fault zone (F19), possess a high CH4/3He-low R (10?8) and high CO2/3He-low R system, with no obvi- ous sign of mantle degassing. Studies have shown that the deep-seated huge fault zones are the major channel ways for mantle degassing, the main factors controlling the intensity of mantle degassing are fault depth, tectonic environment and crust thickness; the intensity of mantle de- gassing can reflect the depth and the status of deep-seated tectonic environment of fault, while the geochemical tracing studies of gases can open up a new research approach; upwelling ac- tivity of hydrothermal fluids from the deep interior of the Earth may be one of the driving forces for the formation and evolution of the huge deep fault zones. Piedmont fault zones are the locations where deep-seated tectonic activity and crust/mantle structure are transformed, which are of great significance in understanding the mechanisms of formation of orogenic belts and basins.TAO Mingxin1,2, XU Yongchang1, SHI Baoguang1, JIANG Zhongti3, SHEN Ping1, LI Xiaobin1 & SUN Mingliang1 1. Key Laboratory of Gas Geochemistry, Lanzhou Institute of Geology, Chinese Academy of Sciences, Lanzhou 730000, China 2. Beijing Normal University, Beijing 100875, China 3. The Practical Geologic Data Center, State Land Resource Department, Sanhe 065201, China 2005Science China Earth Sciences2005,48,7:20
16Dense coding scheme using superpositions of Bell-states and its NMR implementation显示文摘Dense coding using superpositions of Bell-states is proposed. The generalized Grover's algorithm is used to prepare the initial entangled states, and the reverse process of the quantum algorithm is used to determine the entangled state in the decoding measurement. Compared with the previous schemes, the superpositions of two Bell-states are exploited. Our scheme is demonstrated using a nuclear magnetic resonance (NMR)quantum computer. The corresponding manipulations are obtained. Experimental results show a good agreement between theory and experiment. We also generalize the scheme to transmit eight messages by introducing an additional two-state system.ZHANG Jingfu, XIE Jingyi, DENG Zhiwei & LU Zhiheng Key Laboratory for Quantum Information and Measurements, Department of Physics, Tsinghua University, Beijing 100084, China Center for Quantum Information, Tsinghua University, Beijing 100084, China Department of Materials Science and Engineering, Beijing Normal University, Beijing 100875, China Testing and Analytical Center, Beijing Normal University, Beijing 100875, China Department of Physics, Beijing Normal University, Beijing 100875, China 2005Science China(Physics,Mechanics & Astronomy)2005,48,1:18
17Local and non-local sources of airborne particulate pollution at Beijing——The ratio of Mg/Al as an element tracer for estimating the contributions of mineral aerosols from outside Beijing显示文摘A new element tracer technique has firstly been established to estimate the contributions of mineral aerosols from both inside and outside Beijing. The ratio of Mg/Al in aerosol is a feasible element tracer to distinguish between the sources of inside and outside Beijing. Mineral aerosol, inorganic pollution aerosol mainly as sulfate and nitrate, and organic aerosol are the major components of airborne particulates in Beijing, of which mineral aerosol accounted for 32%―67% of total suspended particles (TSP), 10%―70% of fine particles (PM2.5), and as high as 74% and 90% of TSP and PM2.5, respectively, in dust storm. The sources from outside Beijing contributed 62% (38%―86%) of the total mineral aerosols in TSP, 69% (52%―90%) in PM10, and 76% (59%―93%) in PM2.5 in spring, and 69% (52%―83%), 79% (52%―93%), and 45% (7%―79%) in TSP, PM10, and PM2.5, respectively, in winter, while only ~20% in summer and autumn. The sources from outside Beijing contributed as high as 97% during dust storm and were the dominant source of airborne particulates in Beijing. The contributions from outside Beijing in spring and winter are higher than those in summer, indicating clearly that it was related to the various meteorological factors.HAN Lihui1, ZHUANG Guoshun1,2,3, SUN Yele1 & WANG Zifa3 1. The Center for Atmospheric Environmental Study, Department of Chemistry, Beijing Normal University, Beijing 100875, China 2. Center for Atmospheric Chemistry Study, Department of Environmental Science & Engineering, Fudan University, Shanghai 200433, China 3. LAPC/NZC, Institute of Atmospheric Physics, CAS, Beijing 100029, China 2005Science China Chemistry2005,48,3:18
18创新教师教育模式,构建中国特色教师教育体系显示文摘北京师范大学在实现转型的过程中,从我国社会经济和教育发展的需要以及国际教师教育发展的基本趋势出发,就我国教师教育改革面临的一些重要问题进行了创新性研究,形成了较为完整的理论体系;积极推进教师教育模式多元化改革,其中以4+2为核心的教师培养模式改革,主动适应我国基础教育发展对高层次教师的迫切需求,在培养方式、课程设置、实践环节、指导方式、论文写作等方面进行了富有创意的探索,为我国基础教育高素质教师的培养探索出了新的路子。与此同时,还通过整合学校现有的各种资源,初步建立起了职前/职后、培养/培训一体化的教师终身教育体系,拓展和强化了教师教育的传统和特色。Teaching Affairs Office,Beijing Normal University(Teaching Affairs Office,Beijing Normal University,Beijing,100875,China) 2005教师教育研究2005,17,3:17
19Distribution of C_4 plants along the Northeast China transect and its correlation to the environmental factors显示文摘The distribution of C4 plants and the C4/C3 ratio along Northeast China transect (NECT) have been studied. A model to quantify their relation with environmental factors has been set up. The ratio of the number of C4 plants to that of C3 plants along NECT shows two low and two high trends from east to west, and their distribution is mainly decided by annual average temperature and precipitation.TANG HaipingOpen Research Laboratory of Environmental Changes and Natural Disaster of the Ministry of National Education, Beijing Normal University , Beijing 100875, Laboratory of Quantitative Vegetation Ecology , Institute of Botany , Chinese Academy of Sciences , Beijing 100093, China 1999Chinese Science Bulletin1999,44,14:16
20Discovery and character of the Kunlun-Yellow River Movement显示文摘Based on geomorphological, tectonic and sedimentary data, a Kunlun Yellow River Tectonic Movement has been recognized in 1 10-0 60 Ma B.P. This tectonic movement, which leads to uplift of the Qinghai_Xizang (Tibet) Plateau from 1 500 to 3 000-3 500 m, is periodic, abrupt and changeable in the movement rate of uplifting and slide slipping.CUI Zhijiu 1, WU Yongqiu 2,3 and LIU Gengnian 1 1. Department of Geography, Peking University, Beijing 100871, China 2. Open Research Laboratory of Environmental Changes and Natural Disaster of State Education Commission, Beijing 100875, China 1998Chinese Science Bulletin1998,43,10:16
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