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Forecasting the summer rainfall in North china using the year-to-year increment approach

Science china Earth sciences 2009年第4期52卷 532-539页

作者： FAN Ke1, LIN MeiJing1,2 & GAO YuZhong3.1 Nansen-Zhu International Research Center, Institute of Atmospheric Physics, Chinese academy of sciences, beijing 100029, {3. 2.graduate university of the Chinese academy of sciences, beijing 100049, {3. 3.Heilongjiang Meteorological Administration, Harbin 15003., {3. Nansen-Zhu International Research Center Institute of Atmospheric Physics Chinese Academy of Sciences Beijing China graduate university of the Chinese academy of {3. Beijing China Heilongjiang Meteorological Administration Harbin China

A new approach to forecasting the year-to-year increment of rainfall in North china in July-August (JA) is proposed. DY is defined as the difference of a variable between the current year and the preceding year (year-to-year increment). NR denotes the seasonal mean precipitation rate over North china in JA. After analyzing the atmospheric circulation anomalies associated with the DY of NR, five key predictors for the DY of NR have been identified. The prediction model for the DY of NR is established by using multi-linear regression method and the NR is obtained (the current forecasted DY of NR added to the preceding observed NR). The prediction model shows a high correlation coefficient (0.8) between the simulated and the observed DY of NR throughout period 1965-1999, with an average relative root mean square error of 19% for the percentage of precipitation rate anomaly over North china. The prediction model makes a hindcast for 2000-2007, with an average relative root mean square error of 21% for the percentage of precipitation rate anomaly over North china. The model reproduces the downward trend of the percentage of precipitation rate anomaly over North china during 1965-2006. Because the current operational prediction models of the summer precipitation have average forecast scores of 60%-70%, it has been more difficult to forecast the summer rainfall over North china. Thus this new approach for predicting the year-to-year increment of the summer precipitation (and hence the summer precipitation itself) has the potential to significantly improve operational forecasting skill for summer precipitation.

关键词： annual increment North china precipitation prediction prediction skill

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Periodicity of Retzius lines in fossil Pongo from South china

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Chinese Science Bulletin 2012年第7期57卷 790-794页

作者： HU Rong1,2,3. ZHAO LingXia1,2 & WU XinZhi2 1 Key Laboratory of Evolutionary Systematics of Vertebrates, Institute of Vertebrate Paleontology and Paleoanthropology, Chinese academy of sciences, beijing 100044, {3. 2 Laboratory of Human Evolution, Institute of Vertebrate Paleontology and Paleoanthropology, Chinese academy of sciences, beijing 100044, {3. 3.graduate university of Chinese academy of sciences, beijing 100049, {3. Key Laboratory of Evolutionary Systematics of Vertebrates Institute of Vertebrate Paleontology and Paleoanthropology Chinese Academy of Sciences Beijing China Laboratory of Human Evolution Institute of Vertebrate Paleontology and Paleoanthropology Chinese Academy of Sciences Beijing China graduate university of Chinese academy of {3. Beijing China

Periodicity of Retzius lines is a key factor in dental development. In this study, we examined the periodicity of Retzius lines in fossil Pongo from South china using polarized light microscope observation of dental ground sections. The periodicities all of the 15 teeth were 9 d. Comparisons of periodicity were made with extant primates, fossil apes and hominins. Periodicity of fossil Pongo from South china was relatively long but fell within the variation of extant Pongo, Gorilla and modern human, and longer than periodicity of Pan and other extant primates. Fossil Pongo from South china was similar to Lufengpithecus and Sivapithecus, shorter than Gigantopithecus and longer than European and African fossil apes and most early hominins in periodicity. Generally, the periodicities of Asian large-body fossil apes were longer than the periodicities of European and African large-body fossil apes in Miocene. Difference among species and trend of evolution in periodicity were analyzed and discussed. We found that periodicity might gradually increase from Proconsul in early Miocene to several fossil apes in Miocene and then Gigantopithecus in Pleistocene. In addition, this study made correlate analysis between periodicity and body mass respectively in males and females of six extant apes and five fossil apes, and found that periodicity positively correlated with body mass.

关键词：周期性变化中国南方大猩猩化石灵长类动物早中新世类人猿显微镜观察

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Ovular development and perisperm formation in Phytolacca americana (Phytolaccaceae) and their systematic significance in Caryophyllales

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Journal of Systematics and Evolution 2010年第5期48卷 318-325页

作者： Hong-Chun ZHENG Sheng-Wen MA Tuan-Yao CHAI(College of Life Science,graduate university of Chinese academy of {3.,beijing 100049,china) (College of Life Science Graduate University of Chinese Academy of Sciences Beijing 100049 China)

Phytolacca is the biggest and most original genus in Phytolaccaceae and an important genus in plant systematic *** microscopy results show that the Phytolacca americana *** arises from the caulis(floral receptacle).The perisperm and hypostase are simultaneously initiated from the top several layers of cells of chalaza after fertilization,and the perisperm is located between the nucellus and *** the early stages of development,the hypostase cells are thin-walled with dense cytoplasm,clear nuclei,and some reserve ***,at the heart-shaped embryo stage,the hypostase cells are dead and *** main functions of the hypostase may be to maintain cellular division and perisperm growth without delivering nutrient materials to the *** evolutionary picture of placentation in Caryophyllales is also presented.

关键词： hypostase nucellus ovule perisperm Phytolacca placentation.

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Taxonomic revision of Lepisorus(***.) Ching ***(Polypodiaceae) from china

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Journal of Systematics and Evolution 2009年第6期47卷 581-598页

作者： ~(1,2)Xin-Ping QI ~1Xian-Chun ZHANG~* 1(State Key Laboratory of Systematic and Evolutionary Botany,Institute of Botany,Chinese academy of sciences,beijing 100093.{3.) 2.graduate university of Chinese academy of sciences,beijing 100049,{3.) (State Key Laboratory of Systematic and Evolutionary Botany Institute of Botany Chinese Academy of Sciences Beijing 100093 China) (graduate university of Chinese academy of {3. Beijing 100049 China)

The taxonomy of Lepisorus(***.) Ching *** in china was revised based on herbarium specimen examinations,field observations,and microscopic study of rhizome scales,soral paraphyses,leaf epidermis, and *** a result,nine species were recognized:Lepisorus macrosphaerus(Baker) Ching,Lepisorus asterolepis (Baker) Ching,Lepisorus marginatus Ching,Lepisorus kuchenensis(***) Ching,Lepisorus megasorus(***.) Ching,Lepisorus kawakamii(Hayata) Tagawa,Lepisorus subsessilis Ching & ***,Lepisorus affinis Ching, and Lepisorus nudus(Hook.) *** kawakamii(Hayata) Tagawa was reinstated;Lepisorus gyirongensis Ching & *** and Lepisorus longus Ching were reduced to synonyms *** and ***,respectively. The subdivision ofLepisorus macrosphaerus was not *** scales and paraphyses are the most useful characters for species delimitation as well as for infrageneric *** of the leaf epidermis and spore ornamentation are usually stable and thus of great significance in understanding the relationships among groups within the genus.

关键词： china Lepisorus Lepisorus sect.Lepisorus Polypodiaceae taxonomic revision

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A puzzle of the radio-quiet quasar PG 1407+265:Are optical and X-ray emissions produced from a relativistic jet?

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Science china(Physics,Mechanics & Astronomy) 2011年第1期54卷 183-186页

作者： CHEN Liang 1,2,3.& BAI JinMing 1,2 1 National Astronomical Observatories/Yunnan Observatory,Chinese academy of sciences,Kunming 650011,china 2 Key Laboratory for the Structure and Evolution of Celestial Objects,Chinese academy of sciences,Kunming 650011,china 3.graduate university of Chinese academy of sciences,beijing 100049,china National Astronomical Observatories/Yunnan Observatory Chinese Academy of Sciences Kunming China Key Laboratory for the Structure and Evolution of Celestial Objects Chinese Academy of Sciences Kunming China graduate university of Chinese academy of {3. Beijing China

PG 1407+265 is a radio quiet quasar that has a relativistic *** this report,we show some peculiar properties of its optical and X-ray emissions,which indicate possible non-thermal origins produced from the *** use a simple synchrotron + synchrotron self Compton (SSC) model to fit the emissions with different ratios of energy densities between the magnetic field and electrons (η≡U B/U e),which predicts a different γ-ray *** First LAT AGN Catalog (1LAC) did not include PG 1407+265,which indicates an upper limit of γ-ray *** upper limit constrains the ratio to be unreasonably large (η≥10 4-5).This inversely indicates that the optical and X-ray emissions may not be produced from the beaming *** discuss the physical implications of these results.

关键词： active galactic nuclei jet non-thermal emission PG 1407+265

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SHRIMP zircon U-Pb geochronology of early Mesozoic felsic igneous rocks from the southern Lancangjiang and its tectonic implications

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Science china Earth sciences 2006年第10期49卷 1032-1042页

作者： PENG Touping1,2, WANG Yuejun1, FAN Weiming1, LIU Dunyi3. SHI Yuruo3.& MIAO Laicheng4 1. Key Laboratory of Isotope Geochronology and Geochemistry, Guangzhou Institute of Geochemistry, Chinese academy of sciences, Guangzhou 510640, china 2. {3. university of Chinese academy of sciences, beijing 10003., china 3. SHRIMP isotope Laboratory, Chinese academy of Geological sciences, beijing 10003., china 4. Institute of Geology and Geophysics, Chinese academy of sciences, beijing 100029, china Key Laboratory of Isotope Geochronology and Geochemistry Guangzhou Institute of Geochemistry Chinese Academy of Sciences Guangzhou China graduate university of Chinese academy of {3. Beijing China SHRIMP isotope Laboratory Chinese Academy of Geological Sciences Beijing China Institute of Geology and Geophysics Chinese Academy of Sciences Beijing China

The SHRIMP zircon U-Pb geochronology of three typical samples, including two monzo nitic granites from the Lincang batholith and a rhyolite from the Manghuai Formation are presented in the southern Lancangjiang, western Yunnan Province. The analyses of zircons for the biotite monzonitic granites from the northern (02DX-13.) and southern (20JH-10) Lincang batholith show the single and tight clusters on the concordia, and yield the weighted mean 206Pb/23.U ages of 229.4 ± 3.0 Ma and 23..4 ± 3.6 Ma, respectively, representing the crystallized ages of these granites. The zircons for the rhyolitic sample (02DX-95) from the Manghuai Formation give a weighted mean 206Pb/23.U age of 23..0 ± 5.0 Ma. These data suggest that the igneous rocks from the Lincang granitic batholith and Manghuai Formation have a similar crystallized age. In combination with other data, it is inferred that both were generated at a narrow age span (~23. Ma) and were originated from the postcollisional tectonic regime. An early Proterozoic 206Pb/23.U apparent age of 1977±44 Ma is additionally obtained from one zircon from the biotite monzonitic granite (southern Lincang batholith), indicative of devel- opment of the early Proterozoic Yangtze basement in the region. These precisely geochronological data provide important constraints on better understanding the Paleozoic tectonic evolution of the Tethys, western Yunnan Province.

关键词： SHRIMP zircon U-Pb dating, Middle Triassic, Lincang granitic batholith, Manghuai Formation rhyolite, southern Lancangjiang.

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A revision of Clematis ***(Ranunculaceae)

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Journal of Systematics and Evolution 2009年第6期47卷 552-580页

作者： ~(1,2)Wen-Jing YANG ~1Liang-Qian LI~* ~3.ei XIE 1(State Key Laboratory of Systematic and Evolutionary Botany,Institute of Botany,Chinese academy of sciences,beijing 100093.{3.) 2.graduate university of Chinese academy of sciences,beijing 100049,{3.) 3.Southwestern {3. Germplasm Bank of Wild Species,Kunming Institute of Botany Chinese academy of sciences Kunming 650204,{3.) (State Key Laboratory of Systematic and Evolutionary Botany Institute of Botany Chinese Academy of Sciences Beijing 100093 China) (graduate university of Chinese academy of {3. Beijing 100049 China) (Southwestern china Germplasm Bank of Wild Species Kunming Institute of Botany Chinese Academy of Sciences Kunming 650204 China)

Clematis *** is revised in this paper based on the examination of a large number of herbarium specimens,extensive field observations,and morphometric *** taxonomic history and geographical distribution of the section are given,the relationships among the species are discussed,and the evolutionary trends of some characters in the section are *** staminodes of the plants in this section may have evolved from the outer stamens with petaloid filaments and gradually disappearing ***,they may have evolved in two different *** possibility is that the staminodes elongate and become lanceolate,as long as sepals,and their apices turn into *** other is that the staminodes are spathulate,but not elongating,as long as stamens,and their apices turn into retuse from obtuse and *** evolutionary trend of sepals may be from thin to thick in texture,and the veins from non-prominent to *** a result,five new series are established and nine species, two subspecies and nine varieties(including three new ranks) are recognized in this *** identification key is provided,and each taxon is described and *** sibirica and Clematis ochotensis are treated as subspecies of Clematis alpina due to their subtle differences and lack of,or few,overlapping *** fusijamana and Clematisfauriei are recognized as varieties of *** *** for the continuous variation of the velutinous strips on the sepal *** iliensis is treated as variety of *** *** for the continuous variation of leaf division *** variations in sepal color and basal caruncle size support degrading Clematis chiisanensis as a variety of Clematis *** North American *** may be primitive,whereas *** may be the most advanced taxon in this *** and *** are closely related to each ***,the systematic position of se

关键词： Clematis sect.Atragene Ranunculaceae taxonomic revision

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Valuations on arithmetic surfaces

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Science china Mathematics 2009年第1期52卷 66-76页

作者： XU Ning Department of Mathematics, graduate School of Chinese academy of sciences, {3., china Department of Mathematics Graduate School of Chinese Academy of Sciences Beijing China

In this paper, we give the definition of the height of a valuation and the definition of the big field ? p,G , where p is a prime and G ? ? is an additive subgroup containing 1. We conclude that ? p,G is a field and ? p,G is algebraically closed. Based on this the author obtains the complete classification of valuations on arithmetic surfaces. Furthermore, for any m ? p,G n ∈ ?, let V m,n be an ∝-vector space of dimension n - m + 1, whose coordinates are indexed from m to n. We generalize the definition of ? p,G , where p is a prime and G ? V m,n is an additive subgroup containing 1. We also conclude that ? p,G is a field if m ? 0 ? n.

关键词： valuation height rank totally ordered group big field transcendental number 14J10

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Estimating forest aboveground biomass using HJ-1 Satellite CCD and ICESat GLAS waveform data

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Science china Earth sciences 2010年第S1期53卷 16-25页

作者： GUO ZhiFeng1,CHI Hong1,2 & SUN GuoQing1,3.1State Key Laboratory of Remote Sensing Science,Jointly Sponsored by the Institute of Remote Sensing Applications of Chinese academy of sciences and beijing Normal {3.,Institute of Remote Sensing Applications,Chinese academy of sciences,beijing 100101,china 2graduate {3. of Chinese academy of sciences,beijing 100049,china 3.epartment of Geography {3. of Maryland,College Park,MD 20742,USA State Key Laboratory of Remote Sensing Science Jointly Sponsored by the Institute of Remote Sensing Applications of Chinese Academy of Sciences and Beijing Normal University Institute of Remote Sensing Applications Chinese Academy of Sciences Beijing China graduate university of Chinese academy of {3. Beijing China Department of Geography university of Maryland College Park USA

The ecosystem in northeastern china and the Russian Far East is a hotspot of scientific research into the global carbon *** aboveground biomass(AGB) is an important component in the land surface carbon *** this study,using forest inventory data and forest distribution data,the AGB was estimated for forest in Daxinganlin in northeastern china by combining charge-coupled device(CCD) data from the Small Satellite for Disaster and Environment Monitoring and Forecast(HJ-1) and Geoscience Laser Altimeter System(GLAS) waveform data from the Ice,Cloud and land Elevation Satellite(ICESat).The forest AGB prediction models were separately developed for different forest types in the research area at GLAS footprint level from GLAS waveform parameters and field survey plot biomass in the Changqing(CQ) Forest Center,which was calculated from forest inventory *** resulted statistical regression models have a R2=0.68 for conifer and R2=0.71 for broadleaf *** models were used to estimate biomass for all GLAS footprints of forest located in the study *** GLAS footprint biomass coupled with various spectral reflectivity parameters and vegetation indices derived from HJ-1 satellite CCD data were used in multiple regression analyses to establish biomass prediction models(R2=0.55 and R2=0.52 for needle and broadleaf respectively).Then the models were used to produce a forest AGB map for the whole study area using the HJ-1 *** data obtained from forest inventory data of the Zhuanglin(ZL) Forest Center were used as independent field measurements to validate the AGB estimated from HJ-1 CCD data(R2=0.71).About 80% of biomass samples had an error less than 20 t ha-1,and the mean error of all validation samples is 5.74 t *** pixel-level biomass map was then stratified into different biomass levels to illustrate the AGB spatial distribution pattern in this *** was found that HJ-1 wide-swath data and GLAS waveform data can be combined to estim

关键词： Disaster and Environment Monitoring and Forecast Satellite ICESat GLAS waveform boreal forest forest aboveground biomass multiple linear regression

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CMQV+:An authenticated key exchange protocol from CMQV

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Science china(Information sciences) 2012年第7期55卷 1666-1674页

作者： LI Hui 1,2 & WU ChuanKun 1 1 State Key Laboratory of Information Security,Institute of Software,Chinese academy of sciences,beijing 100190,{3. 2.graduate university of Chinese academy of sciences,beijing 100049,{3. State Key Laboratory of Information Security Institute of Software Chinese Academy of Sciences Beijing China graduate university of Chinese academy of {3. Beijing China

Ustaoglu presents a secure and efficient key exchange protocol named CMQV,based on the design rationales of HMQV and *** with the latter two protocols,on one hand,CMQV achieves high performance of HMQV,and on the other,it is proven secure in eCK model as NAXOS ***,CMQV enjoys the security proof under gap Diffie-Hellman assumption as indicated by its *** this paper,we propose a variant of CMQV,called CMQV+,which is proven secure under a weaker assumption (*** Diffie-Hellman assumption) in eCK model with random oracles while maintaining the high-performance feature of CMQV as much as possible.

关键词： key exchange eCK model trapdoor-test technique provable security CDH assumption

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