Sequences Characterization of Microsatellite DNA Sequences in Pacific Abalone(Haliotis discus hannai)   总被引：1，自引：0，他引：1  

Kijima Akihiro 《中国海洋大学学报(英文版)》2007,(1)

1 Introduction Microsatellites or simple sequence repeats (SSRs) are tandemly repeated motifs of one to six bases found in all prokaryotic and eukaryotic genomes analysed to date (Zane et al., 2002). Due to their hyper-variable and co-dominant nature, relatively high abundance and random distribution in the genome, microsatellites are among the most efficient class of molecular markers. Such repeats display high polymorphism because of variation in repeat length and can be rapidly analysed t…  相似文献   

抽样机制对报文长度分布测度影响的研究     

张巍  丁伟  龚俭 《中国海洋大学学报(自然科学版)》2008,(Z1)

Claffy在1994年对1 h的主干数据分析的基础上,提出了基于时间驱动技术比基于报文驱动技术得出的抽样结果要差一些,但是二者之间的差别很小。为验证这个结论是否依然适用,以CERNET某2.5 G省网边界链路3个不同阶段连续1 h报文数据构成的Trace为对象,采用Claffy相似的方法,对报文长度分布测度进行了分析,获得了1组有关的结论,可以用于与网络测量和网络行为学有关的研究。  相似文献   

Sediment burial stimulates the growth and propagule production of Spartina alterniflora Loisel.     

Zifa Deng  Shuqing An  Congjiao Zhao  Lin Chen  Changfang Zhou  Yingbiao Zhi  Hongli Li 《Estuarine, Coastal and Shelf Science》2008,76(4):818-826

Spartina alterniflora Loisel., an extensively invasive species on the Chinese coast, is a focus of increasing management concern due to its high expansion rate in estuaries and tidal zone, and the significant damage it causes to native ecosystems. In order to understand the processes and mechanisms of invasion of S. alterniflora in China, the impact of three sediment types (sand, sand–loam mixture and loam) and five buried patterns (unburied, 50% burial of initial plant height, 75% burial of initial plant height, complete burial and repeated burial) on the growth of seedlings or ramets was investigated. Results showed that each of the three factors (sediment types, burial pattern and plant materials) and interactions between/among them, significantly affected height and clonal growth, and biomass accumulation and allocation. Plant height, total biomass and number of new vegetative propagules significantly increased with progressive burial treatments. However, the complete burial treatment resulted in the death of all plant materials, and the maximum values of three parameters were found in the 50% burial or repeated burial treatments. Plant responses were determined by the instantaneous thickness of sediment of each time burial rather than by the total quantity of repeated burial. The growth of S. alterniflora was not shown to be dependent on specific types of sediment in sedimentation environment. In contrast to the unburied control, the proportion of primary tillers produced directly from initial individuals and the ratio between the aboveground and belowground biomass were greater under burial treatments. Seedlings produced more new vegetative propagules than vegetative offspring in all experimental treatments, and the former were apt to produce ramets from rhizomes rather than primary tillers. It is concluded that under various sedimentation environments, the clonal spread efficiency of seedlings was higher than that of vegetative offspring, and there is a positive feedback relationship between sedimentation and the growth of S. alterniflora. Thus, moderate sedimentation may stimulate the invasion of exotic species, S. alterniflora in coastal China.  相似文献   

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邓建刚  李泽民  张志俊 《大地测量与地球动力学》2009,29(6):74-78

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张静  赵超英  张勤  瞿伟 《大地测量与地球动力学》2009,29(5):143-146

?о?InSAR?α????????????????Kriging????????????????????????????1996??????SAR???????????????????е????????????????÷???????Ч?????α????????????????????????????????  相似文献   

CHEMICAL CHARACTERISTICS OF WATER ENVIRONMENT IN LIMNIC WETLANDS IN THE WESTERN SONGNEN PLAIN, CHINA   总被引：1，自引：1，他引：0  

SONG Xin-shan  YAN Bai-xing  DENG Wei  ZHAI Jin-liang 《中国地理科学(英文版)》2000,10(4):377-382

Duetoregionalhydrogeologicandclimaticconditions,inthewesternSongnenPlain,themostdistinctcharacteristicofwaterenvironmentinlimnicwetlandsisthatmanywaterbodieshavehighsaltcontentsandpHvalues,andsomelimnicwetlandsbelongtosaltmarshes.Thelimnicwetlandsofthisregionarespecialnaturecomplex.Itisimportantfortheutilizationofwetlandresourcesandtheintegrateddevelopmentofsaline-alkalinesoiltostudychemicalcharacteristicsofwaterenvironmentinthisregion.1NATURALENVIRONMENTCHARACTERISTICSOFTHEWE…  相似文献   

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任锴  杨力  赵庆海 《大地测量与地球动力学》2009,29(5):125-128

??QUAD????????????????????????????????????????????÷???????????????????????λ???????????е?????÷????????????漰????????????ú????????????????????  相似文献   

一种基于真实身份的BBS系统实名保障技术   总被引：1，自引：0，他引：1  

张扬  陈萍  吕洁  陈茂科  杨道全 《中国海洋大学学报(自然科学版)》2008,(Z1)

用户身份的真实性一直是BBS系统管理的重要方面之一。采用SAML协议,将跨域单点登录中的认证技术引入到BBS系统中,从而实现了用户采用真实身份登录BBS系统,保证了BBS用户的实名。并以多个高校的BBS系统作为样例,建立起基于真实身份的示范BBS系统。  相似文献   

基于Python的SKA-RASCIL中的天线增益校准实现     

黎静  曹忠  邓辉  王锋  梅盈  戴伟 《天文研究与技术》2021,(2):226-230

天线增益校准是射电天文观测数据处理过程中的一个关键步骤。分析了经典的天线增益校准算法Antsol的基本原理,并基于Python对Antsol算法进行了高性能实现,所完成的程序代码已经集成到平方公里阵列(Square Kilometre Array,SKA)的射电天文模拟校准成像软件(Radio Astronomy Simulation,Calibration and Imaging Library,RASCIL)中,不仅为当前平方公里阵列数据处理提供了支撑,也为未来数据处理的性能优化提供算法参考。  相似文献   

Automatic detection and correction algorithms for magnetic saturation in the SMFT/HSOS longitudinal magnetograms     

徐海清  刘锁  苏江涛  邓元勇  Andrei Plotnikov  白先勇  陈洁  杨潇  郭晶晶  王晓帆  宋永亮 《天文和天体物理学研究(英文版)》2021,(3):158-166

A longitudinal magnetic field often suffers the saturation effect in a strong magnetic field region when the measurement is performed at a single-wavelength point and linear calibration is adopted.In this study,we develop a method that can judge the threshold of saturation in Stokes V/I observed by the Solar Magnetic Field Telescope(SMFT)and correct it automatically.The procedure is to first perform the second-order polynomial fit to the Stokes V/I vs.I/I_m(I_m is the maximum value of Stokes I)curve to estimate the threshold of saturation,then reconstruct Stokes V/I in a strong field region to correct for saturation.The algorithm is demonstrated to be effective by comparing with the magnetograms obtained by the Helioseismic and Magnetic Imager(HMI).The accuracy rate of detection and correction for saturation is~99.4%and~88%respectively among 175 active regions.The advantages and disadvantages of the algorithm are discussed.  相似文献