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Pollen limitation and variation in floral longevity in gynodioecious Potentilla tanacetifolia

Journal of systematics and Evolution 2011年第6期49卷 539-545页

作者： 1,2Hong YAO 1Yi-Bo LUO 1(state Key Laboratory of systematic and Evolutionary Botany,Institute of Botany,chinese academy of s.iences,beijing 100093,china) 2(graduate university of the chinese academy of s.iences,beijing 100049,china) (state Key Laboratory of systematic and Evolutionary Botany Institute of Botany Chinese Academy of Sciences Beijing 100093 China) (graduate university of the chinese academy of s.iences Beijing 100049 China)

Pollination limitation is common in flowering plants and is thought to be a factor driving the evolution of floral *** plasticity of floral longevity to pollination may be an adaptation of plants to pollen ***,this adaptation is less critical in short-lived *** evaluate pollen limitation and the plasticity of floral longevity to pollination in Potentilla tanacetifolia,a gynodioecious herb with short-lived flowers,we analyzed its breeding system,tested sex-differential pollen limitation,and compared variations in floral display size in natural populations in Duolun County,Inner Mongolia,*** pollination experiments and pollinator exclusion treatments revealed that *** is self-compatible and non-autonomously apomictic and shows sex-differential pollen *** plasticity of floral longevity to pollination was observed;the floral duration of female plants was prolonged by approximately 3-4 hours with pollination exclusion ***,the percentage of flowers displayed on female plants during pollination exclusion treatment was significantly higher than that during natural *** natural pollination conditions,the percentage of flowers displayed on female plants was significantly higher than on hermaphrodite ***,approximately 50%of the pollen grains spread out of the anthers of hermaphrodite flowers within 2 h of anthesis;the number of pollen grains adhering to the stigmas of hermaphrodite flowers was significantly higher than that adhering to female flowers when flowers shed their *** results indicate that variation in floral longevity may be an adaptive strategy to pollination conditions for gynodioecious ***.

关键词： floral longevity gynodioecy plasticity pollen limitation Potentilla tanacetifolia.

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Zircon sHRIMP U-Pb geochronology and petrogenesis of the plagiogranites from the Lagkor Lake ophiolite,Gerze,Tibet,china

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chinese science Bulletin 2007年第5期52卷 651-659页

作者： ZHANG YuXiu1,2, ZHANG KaiJun1,3, LI Bing1,2, WANG Yang1,2, WEI QingGuo1,2 & TANG XianChun1,2 1 Key Laboratory of Marginal sea Geology, Guangzhou Institute of Geochemistry, chinese academy of s.iences, Guangzhou 510640, china 2 graduate university, chinese academy of s.iences, beijing 100039, china 3 Department of Earth s.iences, Nanjing university, Nanjing 210093, china Key Laboratory of Marginal sea Geology Guangzhou Institute of Geochemistry Chinese Academy of Sciences Guangzhou China graduate university Chinese Academy of Sciences Beijing China Department of Earth s.iences Nanjing University Nanjing China

地关系与 petrographical 一起， petrological ，和 geochemicalcharacteristics ，和锆石人口，显示从在 Bangong-Nujiang 缝术地区的 Lagkor Lakeophiolite 的 plagiogranites (～ Gerze 县的 20 km 南方，中央西藏，中国)，由在海洋的外壳的运输期间的可锻的砍源于含水的斑粝岩的 anatexis 。因此，这种 plagiogranite 比传播海洋的外壳晚对或很少同时代。锆石虾 166 ±使 2.5 妈变老因为 plagiogranites 显示海洋的盆在中间的侏罗记在 Bangong-Nujiang 地区的西方的部分存在。

关键词：西藏改则县拉果错湖泊蛇绿岩斜长花岗岩锆sHRIMP U-Pb地质年代岩石成因

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Polynomial regression calculation of the Earth's position based on millisecond pulsar timing

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Research in Astronomy and Astrophysics 2012年第2期12卷 219-234页

作者： Feng Tian 1,2,Zheng-Hong Tang 1,Qing-Zeng Yan 1,2 and Yong Yu 11 shanghai Astronomical Observatory,chinese academy of s.iences,shanghai 200030,china 2 graduate university of chinese academy of s.iences,beijing 100049,china shanghai Astronomical Observatory Chinese Academy of Sciences Shanghai 200030 China graduate university of chinese academy of s.iences Beijing 100049 China

Prior to achieving high precision navigation of a spacecraft using X-ray observations, a pulsar rotation model must be built and analysis of the precise posi- tion of the Earth should be performed using ground pulsar timing observations. We can simulate time-of-arrival ground observation data close to actual observed values before using pulsar timing observation data. Considering the correlation between the Earth＇s position and its short arc section of an orbit, we use polynomial regression to build the correlation. Regression coefficients can be calculated using the least square method, and a coordinate component series can also be obtained; that is, we can calcu- late Earth＇s position in the Barycentric Celestial Reference system according to pulse arrival time data and a precise pulsar rotation model. In order to set appropriate param- eters before the actual timing observations for Earth positioning, we can calculate the influence of the spatial distribution of pulsars on errors in the positioning result and the influence of error source variation on positioning by simulation. It is significant that the threshold values of the observation and systematic errors can be established before an actual observation occurs; namely, we can determine the observation mode with small errors and reject the observed data with big errors, thus improving the positioning result.

关键词： autonomous positioning - millisecond pulsar - pulsar timing - re-gression analysis

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A tentative study for the prediction of the CME related geomagnetic storm intensity and its transit time

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science china(Technological s.iences) 2005年第6期48卷 648-668页

作者： ZHAO Xinhua1,2 & FENG Xueshang1,3 1. sIGMA Weather Group, Key Laboratory of space Weather, Center for space science and Applied Re-search, chinese academy of s.iences, beijing 100080, china 2. graduate school of the chinese academy of s.iences, beijing 100039, china 3. school of Geophysics and Geoinformation systems, china university of Geos.iences, beijing 100083, china sIGMA Weather Group Key Laboratory of Space Weather Center for Space Science and Applied Research Chinese Academy of Sciences Beijing China graduate school of the chinese academy of s.iences Beijing China school of Geophysics and Geoinformation systems China University of Geosciences Beijing China

Using 80 CME-ICME events during 1997.1―2002.9, based on the eruptive source locations of CMEs and solar magnetic field observation at the photosphere, a current sheet magnetic coordinate (CMC) system is established in order to study the propagation of CME and its geoeffectiveness. In context of this coordinate system, the effect of the eruptive source location and the form of heliospheric current sheet (HCs) at the eruptive time of CME on the geomagnetic storm intensity caused by CME and the CME’s transit time at the Earth is investigated in detail. Our preliminary conclusions are: 1) The geomagnetic disturbances caused by CMEs tend to have the so-called “same side-opposite side effect”, i.e. CMEs erupt from the same side of the HCs as the earth would be more likely to arrive at the earth and the geomagnetic disturbances associated with them tend to be of larger magnitude, while CMEs erupting from the opposite side would arrive at the earth with less probability and the corresponding geomagnetic disturbance magnitudes would be relatively weaker. 2) The angular separation between the earth and the HCs affect the corresponding disturbance intensity. That is, when our earth is located near the HCs, adverse space weather events occur most probably. 3) The erupting location of the CME and its nearby form of HCs will also affect its arrival time at the earth. According to these conclusions, in this context of CMC coordinate we arrive at new prediction method for estimating the geomagnetic storm intensity (Dstmin) caused by CMEs and their transit times. The application of the empirical model for 80 CME-ICME events shows that the relative error of Dst is within 30% for 59% events with Dstmin≤?50 nT, while the averaged absolute error of transit time is lower than 10 h for all events.

关键词： coronal mass ejections, current sheet magnetic coordinate system, geomagnetic storm intensity, transit time, prediction method.

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

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science china Earth s.iences 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 s.iences, Wuhan 430072, china graduate school of the chinese academy of s.iences, beijing 100039, china Institute of Hydrobiology Chinese Academy of Sciences Wuhan China graduate school of the chinese academy of s.iences Beijing 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.

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Myotoxic activity of a Gln-49 phospholipase A2 from Agkistrodon blomhoffii ussurensis snake venom

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Progress in Natural science:Materials International 2006年第2期16卷 178-182页

作者： BAO Yongming, BU Pengcheng, YANG Jun, YANG Wei, JIA Peilin and AN Lijia (Department of Bioscience and Biotechnology, Dalian university of Technology, Dalian 116024, china Institute of Biophysics, chinese academy of s.iences, beijing 100101, china graduate school of chinese academy of s.iences, beijing 100039, china) Department of Bioscience and Biotechnology Dalian University of Technology Dalian 116024 China Institute of Biophysics chinese academy of s.iences Beijing 100101 China graduate school of chinese academy of s.iences Beijing 100039 China

A novel myotoxic protein phospholipase A2(PLA2), denoted as Gln49-PLA2, has been isolated from snake venom of Agkistrodon blomhoffii ussurensis, which has weak lethal effect and apparent anticoagulant activity, but lacks the PLA2 and hemorrha-genic activity. Gln49-PLA2 obviously increases of plasma creatine-kinase (CK) upon intramuscular injection in mice, suggesting that it may induce a dose-dependent myonecrosis. Histological studies also reveal morphological changes in mouse skeletal muscles, including extensive myonecrosis, hemorrhage and neutrophil infiltration in the treated animals. The myotoxic ability induced by Gln49-PLA2 can be partially inhibited by heparin.

关键词： snake venom phospholipase A2 Agkistrodon blomhoffii ussurensis myotoxic activity.

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Comment on “Evolution model of the earth's limited expanding” from comparative planetology

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chinese science Bulletin 2001年第17期46卷 1495-1496页

作者： sHI Yaolingraduate school, university of science and Technology of china, chinese academy of s.iences, beijing 100039, china graduate school University of Science and Technology of China Chinese Academy of Sciences Beijing China

In the article 'Evolution Model of the Earth’s Limited Expanding' published in Volume 45 Number (4) of chinese science Bulletin[1], the author suggests that the earth expands according to a law R(t) = R0+A(1 -exp(β(t-ts))) (remark: this formula was mistakenly printed as R(t) = R0 + Aexp(β(t-ts)) in the and formula (12) of the text of ref. [1]). According to ref. [1], the earth was formed 4.6 billion years ago. After 0.3 billion years from its birth (ts), it started expansion from an initial radius R0 of 4651 km, and may reach a final maximum radius of R0+A = 6511 km. In the 4.6 billion years history, the radius of the earch has increased by 1720 km, or the density decreased from 14200 km/m3 (2.57 times the present density) to 5520 kg/m3 within the latest 4.3 billion years.

关键词： from comparative planetology Evolution model of the earth’s limited expanding

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Hedychium menghaiense (Zingiberaceae),a new species from Yunnan,china

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Journal of systematics and Evolution 2010年第2期48卷 146-151页

作者： 1,2,3Xiu HU 1Nian LIU 1(Zhongkai university of Agriculture and Engineering,Guangzhou 510225,china) 2(south china Botanical Garden,chinese academy of s.iences,Guangzhou 510650,china) 3(graduate school of chinese academy of s.iences,beijing 100049,china) (Zhongkai university of Agriculture and Engineering Guangzhou 510225 China) (south china Botanical Garden Chinese Academy of Sciences Guangzhou 510650 China) (graduate school of chinese academy of s.iences Beijing 100049 China)

Hedychium menghaiense *** & ***,a new species of the Zingiberaceae from Yunnan Province,china,is described and *** new species is currently known only from its type locality,Nannuoshan Mountain,Menghai County,growing under evergreen broad-leaved forests at altitudes of 1400-1700 *** is similar to Hedychium forrestii Diels,but differs in its narrower and emarginate labellum folded inwards lengthwise,narrower staminodes,and scarlet *** recognition of the new species is supported by the results from analysis of sequence-related amplified polymorphism markers.

关键词： Hedychium Hedychium menghaiense X.Hu & N.Liu new species sRAP markers Zingiberaceae

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Report of Prionospio complex(Annelida:Polychaeta:spio-nidae) from china's waters,with description of a new species

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Acta Oceanologica sinica 2009年第1期28卷 116-127页

作者： ZHOU Jin LI Xinzheng Institute of Oceanology. Chinese Aeademy of Sciences Qingdao 266071 China graduate school Chinese Academy of Sciences Beijing 100039 China

Nine species of Prionospio complex are recorded from china＇s waters,including one new species and six newly recorded ***（Prionospio） pacifica ***.,is characterized by having first and forth pairs of branchiae pinnate,second and third pairs of apinnate,ventral crest on setiger 9 and dorsal crests on setigers *** kirrae（Wilson,1990）,Prionospio（Aquilaspio） convexa Imajima,1990,Prionospio（Minuspio） multibranchiata Berkeley,1927,Prionospio（Prionospio） bocki sderstrm,1920,Prionospio（Prionospio） dubia Maciolek,1985 and Prionospio（Prionospio） paradisea Imajima,1990 are recorded for the first time from china＇s waters.

关键词： taxonomy Prionospio complex new species newly recorded species china's waters.

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structure of augmentation quotients of finite homocyclic abelian groups

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science china Mathematics 2007年第9期50卷 1280-1288页

作者： Guo-ping TANG school of Mathematical s.iences,graduate university of chinese academy of s.iences,beijing 100049,china school of Mathematical s.iences Graduate University of Chinese Academy of Sciences Beijing China

Let G be a finite abelian group and its sylow p-subgroup a direct product of copies of a cyclic group of order p r , i.e., a finite homocyclic abelian group. Let Δ n (G) denote the n-th power of the augmentation ideal Δ(G) of the integral group ring ?G. The paper gives an explicit structure of the consecutive quotient group Q n (G) = Δ n (G)/Δ n+1(G) for any natural number n and as a consequence settles a problem of Karpilovsky for this particular class of finite abelian groups.

关键词： integral group ring augmentation ideal consecutive quotient of augmentation ideal 16s34 20C05

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