Morphological characteristics and phylogenetic relationship of <Emphasis Type="Italic">Anabaena</Emphasis> species from Lakes Dianchi and Erhai,China

Although Anabaena is one of the most prevalent planktonic freshwater genus in China, there are few taxonomic reports of Anabaena strains by morphology and genetics. In this study, morphological characteristics and phylogenetic relationships of seven Anabaena strains isolated from two plateau lakes, Lakes Dianchi and Erhai, were investigated. Morphological characteristics such as morphology of filament, cellular shapes and sizes, relative position of heterocytes and akinetes, and presence or absence of aerotopes, were described for these seven strains. Phylogenetic relationships were determined by constructing 16S rRNA gene tree using the neighbor-joining algorithm. The seven strains were morphologically identified as three groups, and phylogenetic analysis based on 16S rRNA gene sequences also showed that these seven strains were in three groups. Strains EH-2, EH-3, and EH-4 were in group A belonging to the Anabaena circinalis and A. crassa group, and strains DC-1, DC-2, and EH-1 were in group B and identified as A. flos-aquae. Strain DC-3 without aerotopes was significantly different from the other isolated strains and was determined as A. cylindrica. Handling editor: J. Padisak     

Relationships between plant traits and climate in the Mediterranean region: A pollen data analysis

Question: What are the correlations between the degree of drought stress and temperature, and the adoption of specific adaptive strategies by plants in the Mediterranean region? Location: 602 sites across the Mediterranean region. Method: We considered 12 plant morphological and phenological traits, and measured their abundance at the sites as trait scores obtained from pollen percentages. We conducted stepwise regression analyses of trait scores as a function of plant available moisture (α) and winter temperature (MTCO). Results: Patterns in the abundance for the plant traits we considered are clearly determined by α, MTCO or a combination of both. In addition, trends in leaf size, texture, thickness, pubescence and aromatic leaves and other plant level traits such as thorniness and aphylly, vary according to the life form (tree, shrub, forb), the leaf type (broad, needle) and phenology (evergreen, summer‐green). Conclusions: Despite conducting this study based on pollen data we have identified ecologically plausible trends in the abundance of traits along climatic gradients. Plant traits other than the usual life form, leaf type and leaf phenology carry strong climatic signals. Generally, combinations of plant traits are more climatically diagnostic than individual traits. The qualitative and quantitative relationships between plant traits and climate parameters established here will help to provide an improved basis for modelling the impact of climate changes on vegetation and form a starting point for a global analysis of pollen‐climate relationships.     

南天竹资源利用与开发研究

对小檗科南天竹属南天竹的形态结构特征、生长环境及分布、栽培要点及其生态价值、观赏价值、药用价值等开发利用价值各方面作了详细阐述,为更好地开发利用南天竹资源提供科学依据.     

西藏嵩草属（莎草科）的修订

在标本观察和野外调查的基础上,对西藏的嵩草属Kobresia植物进行了分类学修订,共确认了36种和1亚种。更正了6个类群的学名,它们正确的名称是K. esenbeckii,K. fissiglumis,K. gammiei,K. littledalei,K. myosuroides ssp. bistaminata和K. vaginosa。有13个名称,即K. angusta,K. cercostachys var. capillacea,K. clarkeana,K. curticeps var. gyirongensis,K. deasyi,K. glaucifolia,K. hookeri,K. nudicarpa,K. prainii var. elliptica,K. seticulmis,K. stenocarpa,K. stenocarpa var. simplex和K. williamsii处理为异名,其中K. prainii var. elliptica,K. glaucifolia和K. stenocarpa var. simplex为新异名。发现了西藏分布的一个新记录种密穗嵩草K. handel-mazzettii。还收录了最近发表的假钩状嵩草K. pseuduncinoides和阔鳞嵩草K. woodii。此外,重新编制了西藏嵩草属分种和亚种检索表,并较为详细地登记了各类群在西藏的分布地点。     

大眼华鳊和伍氏华鳊的形态差异及其物种有效性

分别对大眼华鳊和伍氏华鳊 137尾标本 7个可数性状和 18个可量性状进行主成分分析 ,以探讨这两个种之间的形态差异及其物种有效性。研究结果显示 :无论是在可数性状上还是可量性状上 ,大眼华鳊和伍氏华鳊之间的形态差异并不显著 ,而且大眼华鳊大陆的标本和台湾的标本无明显的不同。此表明 ,大眼华鳊和伍氏华鳊应该为同一个种。根据国际动物命名法规 ,伍氏华鳊应是大眼华鳊的次定同物异名。     

Grafting the molecular phylogenetic tree with morphological branches to reconstruct the evolutionary history of the genus Zaprionus (Diptera: Drosophilidae)

A molecular phylogeny for the drosophilid genus Zaprionus was inferred using a mitochondrial (CO-II) and a nuclear (Amyrel) gene using 22 available species. The combined molecular tree does not support the current classification, dubbed phylogenetic, based entirely upon a morphocline of forefemoral ornamentation. For species for which DNA was not available, phylogenetic positioning was only assigned using morphological characters. In order to avoid conflict between DNA and morphology in the combined analyses (supermatrix method), we developed a new method in which few morphological characters were sampled according to an a priori homoplasy assessment on the consensus molecular tree. At each internal node of the tree, a number of synapomorphies was determined, and species with no molecular sequences were grafted thereon. Analogously to tree vocabulary, we called our method 'morphological grafting'. New species groups and complexes were then defined in the light of our findings. Further, divergence times were estimated under a relaxed molecular clock, and historical biogeography was reconstructed under a maximum likelihood model. Zaprionus appears to be of recent origin in the Oriental region during the Late Miocene ( approximately 10 MYA), and colonization of Africa started shortly after ( approximately 7 MYA) via the maritime route of the Indian Ocean Islands. Most of the morphological and ecological diversification took place, later, in Western Africa during the Quaternary cyclic climatic changes. Furthermore, some species became recent invaders, with one, Zaprionus indianus, has successfully invaded South and North America during the last decade.     

水牛腔前卵泡的分离方法

为确定水牛腔前卵泡的有效分离方法 ,作者取用来自屠宰场 31头水牛的 6 1个卵巢 ,先用剪刀去掉髓质部 ,然后分别用梳刮法、剪碎法和显微分离法分离回收腔前卵泡。结果发现 ,使用梳刮法时 ,平均每个水牛卵巢回收所得的腔前卵泡数 (15 2 35± 4 4 81)明显高于剪碎法 (32 6 2± 14 81)和显微分离法 (8 95± 3 4 4 ) ,且其平均每个卵巢的处理时间 (39 0 5± 4 2 7min)明显少于剪碎法 (4 6 4 3± 4 15min)和显微分离法 (4 4 5 5± 7 82min)。梳刮法分离所得的腔前卵泡中 ,以原始卵泡最多 (占 4 1 2 5 % ) ,其次为初级卵泡 (占 38 79% ) ,而次级卵泡最少 (仅占 19 95 % )。用梳刮法获得的腔前卵泡在体外培养 72h后 ,存活率为 5 6 38% ,与剪碎法(4 8 91% )及显微分离法 (5 9 34% )没有显著差异。用梳刮法处理 10头黄牛的 2 0个卵巢 ,平均每个卵巢可分离获得 1195 2 0± 6 85 0 0个腔前卵泡 ,明显多于水牛的 15 2 35± 4 4 81个腔前卵泡。由此可见 ,梳刮法是水牛腔前卵泡的有效分离方法     

西藏拉果错卤虫的繁殖特征与成体形态特征

在标准培养条件下研究了西藏拉果错卤虫的繁殖特征和成体形态特征。发现西藏拉果错卤虫与山西解池卤虫及美国大盐湖卤虫在性成熟时间上有较大不同 ,表现为最早抱对时间和最早产F1 代时间均出现较晚 ,且两者间隔时间较长 ,这是对该地区寒冷气候条件的适应。描述了拉果错卤虫雌雄成体的形态特征 ,其中雄性成体选取了 1 2个特征 ,雌性成体选取了 1 3个特征 ,并与世界上几个主要两性生殖卤虫种的成体形态特征做了比较 ,结果显示西藏拉果错卤虫的雌雄成体属于较大的类型 ,但并不像其卵和无节幼体那样显著大于其它品系。聚类分析的结果表明拉果错卤虫的雄性成体和雌性成体均与山西解池卤虫距离最近 ,与伊朗乌尔米湖卤虫距离最远     

RhoA蛋白和cAMP对人前列腺癌细胞株PC-3形态的影响（简报）

小G蛋白RhoA是细胞内信号转导的重要成分,参与对细胞的多种功能活动的调控。溶血磷脂酸（lysophosphatidic acid,LPA）与多种细胞的G蛋白偶连受体结合而发挥作用,除刺激细胞增殖外,还通过活化RhoA,诱导细胞骨架改变。cAMP是经典的第二信使,其下游激酶PKA可抑制RhoA活性,因此,cAMP在许多细胞活动中对RhoA有拮抗作用。     

西太平洋热带水域长体翻车鲀鱼卵和仔稚鱼的空间分布及其形态特征

1978年10月利用向阳红5号调查船对西太平洋14°00′-17°00′S、171°00′-174°00′E热带水域进行鱼类浮游生物调查。调查期间共采集到长体翻车鱼卵27粒和仔稚鱼11尾。长体翻车鱼卵集中分布于调查海域东南部的15°28.4′-16°17.3′S、172°43.8′-173°29.0′E海区,而仔稚鱼主要分布于调查海域东南部的15°28.4′-16°17.3′S、172°43.8′-173°29.0′E和西北部的14°29.0′S、171°48.4′E海域。鱼卵和仔稚鱼的密度分别为1-14粒/100m3和1-3尾/100m3。出现鱼卵和仔稚鱼分布海域的水温和盐度分别为25.72-26.22℃、35.10-35.32和25.72-27.02℃、34.80-35.50。鱼卵和仔稚鱼均出现在海洋锋面处。长体翻车鱼卵为圆球型、浮性、卵膜光滑、透明,卵子直径1.40-1.60mm(1.50±0.054mm,n=27),多油球,20-30个,其直径为0.06-0.16mm(0.10±0.064mm,n=27),卵黄均匀无龟裂。当胚胎发育到尾芽期,可数肌节20对,胚体背部和油球表面出现黑色素细胞分布,皮质体壳已初步形成。孵化前,皮质体壳的表面布满了浓密、细微的小泡,唯尾部和胸鳍外,整个胚体被体壳包住。仔鱼的肛前长为1.20mm(全长1.80mm,体长1.68mm)时,体壳已退化脱尽,肛前长为3.20mm(体长4.00mm)时,鱼体上的部分棘开始退化、变小,尾鳍完全退化、消失,尾锥体萎缩成瘤状,腹部的棘与棘之间出现许多锯齿状小刺。卵子的形状和大小、卵膜的结构、油球的数量、黑色素的分布以及体棘的形状和数量等是区别于其它形目鱼类的卵子和仔稚鱼的依据。