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Comparison of dynamic changes in endogenous hormones and sugars between abnormal and normal Castanea mollissima

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Progress in Natural Science:Materials International 2008年第6期18卷 685-690页

作者： Tao Liua,b,Yunqian Hua,*,Xiaoxian Li a aKunming Institute of Botany,chinese academy of sciences,Kunming 650204,{3. bgraduate university of the chinese academy of sciences,Beijing 100049,{3. Kunming Institute of Botany Chinese Academy of Sciences Kunming 650204 China graduate university of the chinese {3. of sciences Beijing 100049 China

To elucidate the possible functions of endogenous hormones in the flowering of chestnut,concentrations of four endogenous hor-mones[indole-3.acetic acid(IAA),gibberellic acid(GA),abscisic acid(ABA),zeatin riboside(ZR))and the soluble sugars content were measured in both normal and developmentally abnormal chinese chestnut(Castanea mollissima)during flowering and fruiting *** results showed that the contents of ZR,ABA,and GA exhibited a significant dierent pattern in normal trees from that in abnormal trees,while the contents of IAA and soluble sugars showed a similar change pattern between *** results suggest that quantitative changes in endogenous hormones may correspond to dierent flowering and fruiting mechanisms.

关键词： Castanea mollissima Endogenous hormones Soluble sugars

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 43.072,{3. graduate School of the chinese academy of sciences, Beijing 10003.,{3. 1. Institute of Hydrobiology Chinese Academy of Sciences Wuhan 430072 China 2. graduate School of the chinese academy of {3. 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.

The relation between black hole masses and Lorentz factors of the jet components in blazars

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Research in Astronomy and Astrophysics 2009年第3期9卷 293-301页

作者： Ming Zhou1,2,3.and Xin-Wu Cao1,2 1 Shanghai Astronomical Observatory, chinese academy of sciences, Shanghai 20003.,{3. 2 Joint Institute for Galaxy and Cosmology (JOINGC) of SHAO and USMC, Shanghai 20003.,{3. 3.graduate School of the chinese academy of sciences, Beijing 100049,{3. Shanghai Astronomical Observatory Chinese Academy of Sciences Shanghai 200030 China Joint Institute for Galaxy and Cosmology (JOINGC) of SHAO and USMC Shanghai 200030 China graduate School of the chinese academy of {3. Beijing 100049 China

We explore the relationship between black hole mass (MBH) and the motion of the jet components for a sample of blazars. The Very Long Baseline Array (VLBA) 2 cm Survey and its continuation: Monitoring of Jets in active galactic nuclei (AGNs) with VLBA Experiments (MOJAVE) have observed 278 radio-loud AGNs, of which 146 blazars have reliable measurements of their apparent velocities of the jet components. We calculate the minimal Lorentz factors for these sources from their measured apparent velocities, and their black hole masses are estimated with their broad-line widths. A sig- nificant intrinsic correlation is found between black hole masses and the minimal Lorentz factors of the jet components. The Eddington ratio is only weakly correlated with the min- imal Lorentz factor, which may imply that the Blandford-Znajek (BZ) mechanism may dominate over the Blandford-Payne (BP) mechanism for the jet acceleration (at least) in blazars.

关键词： black hole physics — galaxies: active — galaxies: jets — galaxies: nuclei

Experimental Analysis of Shear Strength of Undisturbed Soil in Leucaena Forest in Jiangjia Ravine,Yunnan,china

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Journal of Mountain Science 2010年第4期7卷 386-395页

作者： JIAO Zhen Key Laboratory of Mountain Hazards and earth surfaceprocesses ChineseAcademy of Sciences Chengdu 610041 China graduate university of chinese{3. of sciences Beijing I ooo49 China Institute of Mountain Hazards and Environment Chinese Academy of Science Chengdu 61oo41 China

Five leucaena trees of similar age were chosen in Jiangjia Ravine of Dongchuan,Yunnan Province,china,near which the soil samples were collected by digging profiles 2m in depth and 1m in *** each section,soil samples at different depths were taken for direct shear experiments to determine the root amount and mechanical *** is found that the cohesion and internal friction angle of the undisturbed soil are related to the root amount,depth,clay content and breccias *** correlates negatively with root content,a finding that differs from that of other *** addition,internal friction angle correlates positively with all these factors.

关键词： Jiangjia Ravine Leucaena Undisturbedsoil Shear strength Impact factors

Identification of the Angel -related elements in cyprinid fishes and their phylogenetic implications

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Progress in Natural Science:Materials International 2007年第2期17卷 168-171页

作者： WANG Li, HE Shunping and CHEN Yiyu ( Institute of Hydrobiology, chinese academy of sciences, Wuhan 43.072,{3. graduate School of the chinese academy of sciences, Beijing 10003.,{3. National Natural Science Foundation of{3., Beijing 100085,{3.) [a]chinese academy of sciences Institute of Hydrobiology Wuhan China [b]graduate School of the chinese academy of {3. Beijing China [c]National Natural Science Foundation of china Beijing China

Angel-related element belongs to the family of miniature inverted-repeat transposable elements (MITEs). In this paper we report the identification of an Angel- related element in the series Leuciscini of cyprinid fishes, which is located in the second intron of the growth hormone (GH) gene. We have also found that this element is absent in orthologous locus in the series Barbini of cyprinid fishes, that provides new evidence for the monophyly of the series Leuciscini. The insertion of Angel -related element into the GH gene might take place in the common ancestor of the series Leuciscini after its divergence from the series Barbini. The high sequence divergence and relatively broad species distribution of Angel-related elements implies that they might be ancient transposons which appeared about 26 million years ago.

关键词： Angel -related elements the series Leuciscini monophyly.

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 sciences,Shanghai 20003.,{3. 2 graduate university of chinese academy of sciences,Beijing 100049,{3. Shanghai Astronomical Observatory Chinese Academy of Sciences Shanghai 200030 China graduate university of chinese academy of sciences 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

Impact of the Wenchuan Earthquake on Tourism in Sichuan,china

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Journal of Mountain Science 2008年第3期5卷 194-208页

作者： YANG Weiqiong CHEN Guojie WANG Daojie Institute of Mountain Hazard and Environment Chinese Academy of Sciences Chengdu 610041 China graduate university of chinese academy of sciences Beijing 100049 China

An intensive earthquake, the Wenchuan Earthquake of 8.0 on the Richter scale, struck western Sichuan, china on May 12, 2008. The earthquake has tremendously affected all industries in the quake-hit areas, with no exception of the local tourism. The study of the effect of the earthquake on tourism enriches the theory of tourism, and more importantly, it well serves as the foundation for policy making. The objective of this study is to outline for readers the empirical findings on the various ways that the earthquake affected the operations and viability of tourism in the quake-hit areas. This paper is mainly divided into 3.parts. The first part is to discuss the importance of tourism in the quake-hit areas. The second is to analyze the influencing factors of tourism. The third is to assess the impact of the earthquake on tourism in Sichuan in different seasons.

关键词： Wenchuan Earthquake Tourism Impact factors of Tourism Economic Loss

Patterns of platinum-group elements in mantle peridotite, granulite xenoliths and basalt in Hannuoba

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chinese Science Bulletin 1999年第18期44卷 1676-1681页

作者： CHU Xuelei, LI Xiaolin, XU Jiuhua and LIU Jianming1. The Research Center of Mineral Resources Exploration , chinese academy of sciences , Beijing 100101,{3. 2. Institute of Geology , chinese academy of sciences , Beijing 100029,{3. 3. Institute of High Energy Physics , chinese academy of sciences , Beijing 100817 ,{3. 4. Beijing university of Science and Engineering , Beijing 100083.{3. Corresponding author The Research Center of Mineral Resources Exploration Chinese Academy of Sciences Beijing China Institute of Geology Chinese Academy of Sciences Beijing China Institute of High Energy Physics Chinese Academy of Sciences Beijing China Beijing university of Science and Engineering Beijing China

Neutron activation analysis after preconcentration of nickel sulfide fire assay was used in measurement of Ru, Ph, Pd, Os, Ir, Pt (i.e. PGE elements) and Au concentrations for basalt, mantle and granulite xenoliths in Hannuoba. The chondrite- and primitive mantle-normalized PGE patterns generally exhibit flat (for Iherzolite), negative slope (for harzburgite),

关键词： mantle xenolith granulite xenolith basalt platinum-group element Hannuoba.

A two-round honest-verifier zero-knowledge protocol

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Science china(Information sciences) 2010年第5期53卷 954-963页

作者： LIU HanWu 1,2 & LIN DongDai 1 1 The State Key Laboratory of Information Security, Institute of Software, chinese academy of sciences, Beijing 100190,{3. 2 graduate university of the chinese academy of sciences, Beijing 100049,{3. 1. The State Key Laboratory of Information Security Institute of Software Chinese Academy of Sciences Beijing 100190 China2. Graduate University of the Chinese Academy of Sciences Beijing 100049 China

Since the concept of zero-knowledge protocols was introduced, it has attracted a lot of attention and in turn showed significant effect on the development of cryptography, complexity theory and other areas. The round complexity of a zero-knowledge protocol is a very important efficiency consideration, and it is required to be as small as possible. Generally, it is desirable to have zero-knowledge protocols with constant numbers of rounds. Goldreich and Oren proved that only languages in BPP have one-round and two-round zero-knowledge protocols. Moreover, they also showed that only languages in BPP have one-round honest-verifier zero-knowledge protocols. The notion of honest-verifier zero-knowledge protocols is highly non-trivial and fascinating itself, and has many other uses. Thus, the problem as to whether there exist two-round honest-verifier zero-knowledge protocols becomes an important open problem. In this paper, we introduce a new simulation technique and present a two-round honest-verifier zero-knowledge protocol for any language in N P under a standard complexity assumption based on this technique.

关键词： proof system argument system zero-knowledge witness indistinguishability black-box one-way permutation commitment scheme zap