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Analysis on genetic diversity of mangrove species of Sonneratia and relationship to plant introduction

Acta Oceanologica Sinica 2001年第3期20卷 427-434页

作者： Zhou Hantao, Lin Peng 1. school of life sciences, Xiamen university, Xiamen 361005, china school of life sciences Xiamen University Xiamen 361005 China

RAPD markers were used to assess the relationships among 6 species of Sonneratia in the National Mangrove Nature Reserve of Dongzhai Harbor in Hainan. By using the 15 effective 10 -oligonucleotide arbitrary primers, a total of 512 DNA bands were amplified, among which 297 (58.01%) were polymorphic. Based on UPGMA cluster analysis of 512 DNA bands amplified by the thirty primers, a DNA molecular dendrogram was established, which divided 6 species of Sonneratia into three main groups. Group A included 4 species: Sonneratia apetala , S. hainanensis, S. abla, S. ovata, and Group B: S. paracaseolaris and Group C: S. caseolaris only contained one species respectively. Group A could be divided into two subgroups, A1; Sonneratia apetala , S. hainanensis, S. covata and A2: S. abla; Two populations of Sonneratia apetala, which were from Hainan and Fujian (introduced from Hainan) respectively, were compared by RAPDs. The phenotypic frequencies detected by the 15 primers were calculated and used to estimate diversity (H) within sub-populations. Fujian sub-population exhibited 0.669 and Hainan exhibited 0.671 variability. Shannon's index of phenotypic diversity was then used to partition the diversity within and between sub-populations components. An assessment of the proportion of diversity present within sub-populations, Hpop/Hsp = 0.933, compared with that between sub-populations, (Hsp- Hpop) /Hsp = 0.067, indicates that, on average, most of the diversity (93.3%) is detected within sub-populations; while only 6.7% between populations. The plant introduction of S. hainanensis and S. ovata, which have the nearer genetic distance with Sonneratia apetala , is also discussed.

关键词： Sonneratia RAPD genetic diversity plant introduction

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Sharpness on the Lower Bound of the lifespan of Solutions to Nonlinear Wave Equations

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Chinese Annals of Mathematics,Series B 2011年第4期32卷 521-526页

作者： Yi ZHOU 1 Wei HAN 2 1 Nonlinear Mathematical Modeling and Methods Laboratory Shanghai Key Laboratory for Contem- porary Applied Mathematics school of Mathematical sciences, Fudan university, Shanghai 200433, china. 2.school of Mathematical sciences, Fudan university, Shanghai 200433, china Department of Mathematics, North university of china, Taiyuan 030051, china. Nonlinear Mathematical Modeling and Methods Laboratory Shanghai Key Laboratory for Contemporary Applied Mathematics School of Mathematical Sciences Fudan University Shanghai 200433 China

This paper is devoted to proving the sharpness on the lower bound of the lifespan of classical solutions to general nonlinear wave equations with small initial data in the case n = 2 and cubic nonlinearity （see the results of T. T. Li and Y. M. Chen in 1992）. For this purpose, the authors consider the following Cauchy problem： { where □=δt^2-∑i=1n δx^^2 is the wave operator, g（x）（≡/） 0 is a smooth non-negative function with compact support, and ε 〉 0 is a small parameter. It is shown that the solution blows up in a finite time, and the lifespan T（ε） of solutions has an upper bound T（ε） ≤ exp（Aε-2） with a positive constant A independent of ε, which belongs to the same kind of the lower bound of the lifespan.

关键词： Nonlinear wave equation Cauchy problem lifespan

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Split-plot designs with general minimum lower-order confounding

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Science china Mathematics 2010年第4期53卷 939-952页

作者： WEI JiaLin 1,4,YANG JianFeng 1,LI Peng 3 & ZHANG RunChu 1,2,1 school of Mathematical sciences and LPMC,Nankai university,Tianjin 300071,china 2 KLAS and school of Mathematics and Statistics,Northeast Normal university,Changchun 130024,china 3 school of Mathematical sciences,Capital Normal university,Beijing 100037,china 4 school of sciences,Tianjin university of Commerce,Tianjin 300134,china 1. school of Mathematical sciences and LPMC Nankai University Tianjin 300071 China4. School of Sciences Tianjin University of Commerce Tianjin 300134 China3. School of Mathematical Sciences Capital Normal University Beijing 100037 China2. KLAS and School of Mathematics and Statistics Northeast Normal University Changchun 130024 China

Split-plot designs have been widely used in industrial *** to now,most methods for choosing this kind of designs are based on the minimum aberration (MA) ***,by introducing a new pattern,called aliased effect-number pattern (AENP),Zhang et *** a general minimum lowerorder confounding (denoted by GMC for short) criterion and established a general minimum confounding (also denoted by GMC for saving notations) *** is proved that,the GMC criterion selects optimal designs in a more elaborate manner than the existing ones,and when an experimenter has a prior about the importance ordering of factors in experiments the GMC designs are better than other optimal *** this paper we extend the GMC criterion to the split-plot design case and give a GMC-FFSP criterion for ranking split-plot *** comparisons of the new criterion with the MA-MSA-FFSP criterion are given,and the optimal 32-run split-plot designs up to 14 factors under the two criteria are tabulated for comparison and application.

关键词： fractional factorial design GMC criterion minimum aberration split-plot

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Permian carbonates of Baoshan block, Western Yunnan and their paleoclimatic implications

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Science china Earth sciences 2004年第5期47卷 385-392页

作者： YAN Jiaxin1, LIANG Dingyi1 & WU Ming2 1. Faculty of Earth sciences, china university of Geosciences, Wuhan 430074, china 2. College of Chemistry and life sciences, South-Central university for Nationalities, Wuhan 430074, china china Univ Geosci Fac Earth Sci Wuhan 430074 Peoples R China S Cent Univ National Coll Chem & Life Sci Wuhan 430074 Peoples R China

Recently, much attention has been paid to the climatic significance of carbonates originating in shallow water. Permian carbonates of shallow shelf origin are present in the upper part of the Dingjiazhai Formation, the upper part of the Yongde Formation, and the Shazipo Formation on the Baoshan block of Western Yunnan. Their skeleton and non-skeleton grain as-sociations have been investigated in this study. The carbonates of the Dingjiazhai Formation indicate a Bryonoderm (bryozoans-echinoderm) association without non-skeleton grains. The carbonates of Yongde and Shazipo formations show Chloroforam (green algae-foraminifers) association with peloids. Oolites develop in the Shazipo Formation. Based on the comparisons of grain association with coeval carbonates formed in different paleolatitudes (i.e. various paleo-climatic zones), the carbonates of the Dingjiazhai Formation were thought to have been accu-mulated in shelf environments of warm-temperate zone, and those of the Yongde and Shazipo formations in shelf environments of warm-water.

关键词： Early Permian, carbonate, paleoclimate, Western Yunnan.

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Fuzzy Evaluation of Thermal Comfort in Naturally Ventilated Residential Buildings in china

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湖南大学学报（自然科学版） 2009年第S1期36卷 71-74页

作者： WANG Yi1,NIU Tian-cai1,LIU Jia-ping2,XIAO Yong-qiang2,3(1.school of Environmental and Municipal Engineering,Xi’an university of Architecture and Technology,Xi’an,Shaanxi 710055,china 2.school of Architecture,Xi’an university of Architecture and Technology,Xi’an,Shaanxi 710055,china 3.school of Physical Education,Xi’an university of Architecture and Technology,Xi’an,Shaanxi 710055,china) school of Environmental and Municipal Engineering Xi'an University of Architecture and Technology Xi'an 710055 China school of Architecture Xi'an University of Architecture and Technology Xi'an 710055 China school of Physical Education Xi'an University of Architecture and Technology Xi'an 710055 China

In order to assess the differences between the human body thermal sensation in naturally ventilated space and that in air-conditioned space,the fuzzy evaluation model was adopted in the research of thermal sensation in naturally ventilated *** on the questionnaires and field measurements,the membership functions were presented by the statistic of the covering frequency to the fuzzy ***-bulb temperature was taken as the only independent variable for membership *** maximum values of membership grades are all at 0.5 or so,which is a distinction character on thermal comfort of naturally ventilated *** the calculating results of membership grades value to different fuzzy evaluation subsets,the Predicted Mean Vote(PMV)was ***,energy coefficient(Ea)was introduced to calculate the energy consumption,and the prediction methods of residential building energy consumption were also ***,the importance of evaluation model of thermal sense is shown through the energy consumption prediction in a specific residential building.

关键词： natural ventilated space thermal sensation fuzzy evaluation membership functions

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Science china Earth sciences 2004年第10期47卷 896-911页

作者： ZHANG Changhou1,2, WU Ganguo1,2, WANG Genhou2, ZHANG Weijie2 & SONG Honglin2 1. Key Laboratory of Lithospheric Tectonics and Lithoprobing Technology, china university of Geosciences, Ministry of Education of china, Beijing 100083, china 2. school of Earth sciences and Mineral Resources, china university of Geosciences, Beijing 100083, china 1. Key Laboratory of Lithospheric Tectonics and Lithoprobing Technology China University of Geosciences Ministry of Education of China 100083 Beijing China 2. school of Earth sciences and Mineral Resources China University of Geosciences 100083 Beijing China

The northwest trending tectonic belt in the middle part of the Mesozoic intraplate Yanshan Orogenic Belt, northeast Hebei Province, is composed of thrusts, extensional faults, strike-slip faults and syntectonic sedimentations as well. The northeastward basement-involved major thrusting deformation occurred between 174Ma and 168MaBP and was followed by an intrusion of the granitic plutonic rocks. As a part of the post-thrusting extensional deformations a northwest extending volcano-sedimentation system of Late Jurassic and Early Cretaceous formed in the southwest side of the belt. These volcano-sedimentary sequences are divided into Tuchengzi Formation, Zhangjiakou Formation, Yixian Formation and Jiufotang Formation re- spectively. They are characterized by southeastward migration as a result of the increasing down-dip slip displacement along the major extensional fault toward the southeast of the belt. The provenance area of the Jiufotang Formation north to it experienced southwestward thrusting during and after its later sedimentation. The thrusting in this stage resulted in the formation of an asymmetric footwall syncline with vergence to SW in the Jiufotang Formation in the NE side of the basin. Finally a dextral strike-slip deformation occurred along the NW tectonic belt. The striking tectono-geomorphological features and present seismic activities along this belt indicate that it has been being active since Cenozoic era and is still in the active state at present. This northwest extending tectonic belt was following the same direction and location as the existing fault systems within the basement as revealed by former geological and geophysical studies. So it is reasonable to infer the Mesozoic deformation along this belt to be a result of reactivation of the basement structures in a favorable tectonic stress field. The reactivation of basement struc- tures might be taken as one of the mechanisms of intraplate deformation and orogeny.

关键词： Yanshan Orogenic Belt, northwest extending tectonic complex, thrust system, geochronology.

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Some basic concepts and problems on the petrogenesis of intra-plate ocean island basalts

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Chinese Science Bulletin 2009年第22期54卷 4148-4160页

作者： NIU Yaoling1,2,3 1 Department of Earth sciences, Durham university, Durham DH1 3LE, UK 2.school of Earth sciences and Resources, china university of Geosciences, Beijing 100083, china 3 school of Earth and Space sciences, Peking university, Beijing 100871, china Department of Earth sciences Durham University Durham DH1 3LE UK school of Earth sciences and Resources China University of Geosciences Beijing 100083 China school of Earth and Space sciences Peking University Beijing 100871 China

Basaltic magmatism that builds intra-plate ocean islands is often considered to be genetically associated with "hotspots" or "mantle plumes". While there have been many discussions on why ocean island basalts (OIB) are geochemically highly enriched as an integral part of the mantle plume hypothesis, our current understanding on the origin of OIB source material remains unsatisfactory, and some prevailing ideas need revision. One of the most popular views states that OIB source material is recycled oceanic crust (ROC). Among many problems with the ROC model, the ocean crust is simply too depleted (e.g., [La/Sm]PM > 1) OIB. Another popular view states that the enriched component of OIB comes from recycled continental crust (RCC, i.e.; terrigenous sediments). While both CC and OIB are enriched in many incompatible elements (e.g., both have [La/Sm]PM >>1), the CC has characteristic enrichment in Pb and deletion in Nb, Ta, P and Ti. Such signature is too strong to be eliminated such that CC is unsuitable as source material for OIB. Plate tectonics and mantle circulation permit the presence of ROC and RCC materials in mantle source regions of basalts, but they must be volumetrically insignificant in contributing to basalt magmatism. The observation that OIB are not only enriched in incompatible elements, but also enriched in the progressively more incompatible elements indicates that the enriched component of OIB is of magmatic origin and most likely associated with low-degree melt metasomatism. H2O and CO2 rich incipient melt may form in the seismic low velocity zone (LVZ). This melt will rise because of buoyancy and concentrate into a melt rich layer atop the LVZ to metasomatize the growing lithosphere, forming the metasomatic vein lithologies. Erupted OIB melts may have three components: (1) fertile OIB source material from depth that is dominant, (2) the melt layer, and (3) assimilation of the metasomatic

关键词：岩石成因论海洋 OIB 矿物学

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Sieve M-estimation for semiparametric varying-coefficient partially linear regression model

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Science china Mathematics 2010年第8期53卷 1995-2010页

作者： HU Tao 1,2 & CUI HengJian 1,2 1 school of Mathematical sciences,Beijing Normal university,Laboratory of Mathematics and Complex Systems,Ministry of Education,Beijing 100875,china 2.school of Mathematical sciences,Capital Normal university,Beijing 100048,china 1. school of Mathematical sciences Beijing Normal University Laboratory of Mathematics and Complex Systems Ministry of Education Beijing 100875 China2. School of Mathematical Sciences Capital Normal University Beijing 100048 China

This article considers a semiparametric varying-coefficient partially linear regression *** semiparametric varying-coefficient partially linear regression model which is a generalization of the partially linear regression model and varying-coefficient regression model that allows one to explore the possibly nonlinear effect of a certain covariate on the response variable.A sieve M-estimation method is proposed and the asymptotic properties of the proposed estimators are *** main object is to estimate the nonparametric component and the unknown parameters *** is easier to compute and the required computation burden is much less than the existing two-stage estimation ***,the sieve M-estimation is robust in the presence of outliers if we choose appropriate ρ(·).Under some mild conditions,the estimators are shown to be strongly consistent;the convergence rate of the estimator for the unknown nonparametric component is obtained and the estimator for the unknown parameter is shown to be asymptotically normally *** experiments are carried out to investigate the performance of the proposed method.

关键词： partly linear model varying-coefficient robustness optimal convergence rate asymptotic normality

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A model of necrotic degeneration in Drosophila

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生物物理学报 2009年第S1期25卷 48-49页

作者： Lei Liu school of life sciences, Peking university

Cell death during development or pathological conditions can be classified into three types based on morphology and genetic pathways: apoptosis, autophagic necrosis and

关键词： necrotic degeneration vesicular Drosophila classified expressing progression muscular dystrophy seizure

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A simple solution route to control synthesis of Fe_3O_4 nanomaterials at low temperature and their magnetic properties

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Science china Chemistry 2009年第7期52卷 916-923页

作者： LIU Yi1,2, CHEN Yun1, ZENG YuPing2 & WANG ShiLong3 1 Department of Chemistry and Chemical Engineering, Zaozhuang university, Zaozhuang 277160, china 2 Shanghai Institute of Ceramics, Chinese Academy of sciences, Shanghai 200050, china 3 school of life Science and Technology, Tongji university, Shanghai 200092, china 1. Department of Chemistry and Chemical Engineering Zaozhuang University Zaozhuang 277160 China 2. Shanghai Institute of Ceramics Chinese Academy of Sciences Shanghai 200050 China 3. school of life Science and Technology Tongji University Shanghai 200092 China

A series of nanostructured iron compounds including cubic Fe3O4 and orthorhombic FeOOH were synthesized via a facile low temperature (in the range of 60-100℃) solution method. In the whole process, the interaction between FeCl2·4H2O and methenamine (C6H12N4) was carried out through a reflux device under different reaction conditions such as temperature, solvent, and duration. The samples were detected by XRD, TEM, SAED, physical property measurement system, and Mssbauer spectroscopy, separately. The experiments showed that magnetic mixture nanoparticles had flake and rod morphologies, and cubic Fe3O4 took on grain nanostructure. Magnetism measurements indicated that the saturated magnetization of the as-obtained magnetic mixture was lower than that of the cubic magnetite. Mssbauer spectroscopy testified the sample consisting of cubic magnetite rather than γ-Fe2O3. In addition, a possible growth mechanism of cubic magnetic nanoparticles under different conditions was discussed.

关键词： magnetic nanoparticles cubic Fe3O4 oxidation-coprecipitation method reflux magnetic properties at room temperature Mssbauer spectrum

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