容器大小对不同基因型果蝇发生量影响的遗传分析

果蝇发生量是数量性状,选用野生型、檀黑体、残翅和白眼四种不同基因型的果蝇,设计25种不同的杂交组合,并将其培养在不同大小的容器内,统计各种组合的子代果蝇发生量。经方差分析,结果表明:环境(不同容器大小)对果蝇的发生量影响最大。不同基因型以及基因型与环境的互作对果蝇发生量的影响在不同的杂交组合中也达到极显著差异或显著差异。说明果蝇的发生量是由基因型和环境交互作用的结果。     

植物化控在果树生产中的主要应用

本文综述了植物化控对果树的生长发育、开花结实、果实品质、休眠等方面的影响及应用现状,并简要介绍了植物生长调节剂在果树栽培中的残毒问题。     

珊瑚礁算法的改进研究

珊瑚礁算法易于陷入局部最优且寻优精度低，因此提出一种改进的珊瑚礁算法.此算法借鉴粒子群算法、高斯变异和模拟退火算法的思想改进珊瑚礁算法的内部有性繁殖、无性繁殖和更替机制，提高了算法的寻优精度并可跳出局部最优.在仿真实验中，将改进珊瑚礁算法与基本珊瑚礁算法和粒子群算法等10种算法分别在高维和低维测试函数下进行比较.实验结果表明，改进的珊瑚礁算法不仅较其他算法具有更好的收敛速度和精度，而且在高维测试函数中，仍然可以保持良好的性能.     

不同绿藻浓度下铜绿微囊藻对轮虫生活史的影响

利用生命表实验,研究了不同斜生栅藻浓度下,铜绿微囊藻对萼花臂尾轮虫和红臂尾轮虫生活史的影响.结果表明:当斜生栅藻浓度较高(105,106cells/m L)时,铜绿微囊藻对萼花臂尾轮虫的存活和繁殖有抑制作用,对照组轮虫的rm、R0均显著高于铜绿微囊藻组中的值(p0.01);当斜生栅藻浓度较低(104cells/m L)时,铜绿微囊藻对萼花臂尾轮虫种群则有一定的促进作用.任一斜生栅藻浓度下,铜绿微囊藻对红臂尾轮虫种群存活和繁殖及生活史特征参数均有抑制作用,且这种抑制作用随斜生栅藻浓度的升高而减弱.说明铜绿微囊藻对轮虫的作用受其他可食性绿藻食物浓度的影响,且这种影响随轮虫种类的不同而有差异.     

基于模糊最近邻聚类学习算法的海水藻类繁殖状态预测

为了预报海洋赤潮等灾害的发生,需要监测海水中藻类的繁殖状况.通过建立针对海水中叶绿素a浓度状态的预测模型间接预测海水中藻类的繁殖生长状况.运用基于数据的模糊最近邻聚类学习算法对采样数据进行聚类处理,基于最优模糊逻辑系统建立了针对海水叶绿素a浓度状态的预测模型.根据采样数据的特点和降低模型阶次的实际需求,设计了改进的模糊...     

几种植物提取物对瘤胃体外培养物甲烷生成的影响

采用体外瘤胃培养技术,研究凤仙花、青蒿等植物提取物的降甲烷效果.比较培养瓶中甲烷浓度,4种植物提取物与对照比较均可以显著降低甲烷生成,培养30 h时,青蒿、蒲公英、麻黄和凤仙花处理的甲烷含量分别比对照降低24.0%、30.9%、41.7%和46.21%.凤仙花效果最明显,与莫能菌素效果接近.比较凤仙花提取物不同添加量对...     

论培训品牌的塑造——以胜利油田胜利采油厂职工培训学校为例

以胜利采油厂职工培训学校为例,介绍了其品牌形象的塑造,指出塑造品牌形象、建立高素质的师资队伍以及丰富品牌内涵,是品牌培训的核心内容。     

Morphology and biology of a new Rhynchospio species (Annelida: Spionidae) from the South China Sea,Vietnam, with the review of Rhynchospio taxa

Adults of a new spionid polychaete, Rhynchospio nhatrangi, inhabit sandy tubes on muddy sand intertidal flats in an estuary of Nha Trang Bay, southern Vietnam. The worms are up to 8 mm long and 0.5 mm wide for 55 chaetigers. They are unique among spionids in the changes in the arrangement of hooks during ontogenesis: first development of tridentate hooks in neuropodia from chaetiger 10, later loss of hooks in chaetiger 10, and replacement of tridentate hooks by heavy unidentate hooks in neuropodia of chaetigers 11–14. Adults are simultaneous hermaphrodites having sperm in chaetigers 11–14 and oocytes from chaetiger 15 to 23–33. Spermatozoa are introsperm, about 300 µm long. Oocytes are about 120 µm in diameter, with a thin and smooth envelope. Fertilization and early larval development occur in a hatchery formed by elongated dorsal capillaries on the posterior chaetigers. Larvae escape from the hatchery probably when they have developed four chaetigers and then continue development in seawater, feeding on the plankton. When larvae have grown to 14–15 chaetigers, they likely undergo gradual metamorphosis and settle on the bottom. Metameric nuchal organs, glandular pouches in neuropodia, metanephridial segmental organs, hermaphroditism, sperm, and early larval morphology are described here for the first time for Rhynchospio species. An identification key is provided to eight currently recognized Rhynchospio species.     

Breeding biology of the rapids frog Limnomedusa macroglossa (Anura: Cycloramphidae) in southern Brazil

Limnomedusa is a monotypic genus that occurs in association with rocky outcrops and stream beds. Based on observational and mark–recapture fieldwork from 2005 to 2008, we report the breeding biology of Limnomedusa macroglossa in southern Brazil. The reproductive season lasted from late August to early February. Tadpoles were recorded from early September to late February. A clear pattern of emergence/recruitment was observed in juveniles. The occurrence of reproductive activities was clearly related to the longest photoperiods, when the highest temperatures occur. Males called from rocky or concrete substrates, mostly under rocks. Amplexus was axillary and the operational sex ratio was nearly even. Spawn occurred in lentic water bodies but tadpoles also completed their development in slow‐flowing water. Although using similar habitats for reproduction, L. macroglossa reached lower levels of specialization toward terrestriality than did the cycloramphids Cycloramphus and Thoropa. We classify L. macroglossa as a breeding habitat specialist that would be threatened by river damming.