粗野鹿角珊瑚生物碱的体外抗菌活性研究

[目的]为获得低毒廉价的抗菌活性良好的化合物奠定基础。[方法]采用牛津杯法和试管二倍稀释法分别测定粗野鹿角珊瑚生物碱对溶珊瑚弧菌、塔氏弧菌、鲨鱼弧菌的敏感性、最小抑菌浓度(MIC)和最小杀菌浓度(MBC),并与环丙沙星进行比较。[结果]粗野鹿角珊瑚生物碱对3种弧菌的体外抗菌活性与环丙沙星相近。[结论]该研究可为进一步研究粗野鹿角珊瑚生物碱的结构及修饰提供参考,为开发新的渔药提供新思路。     

南极磷虾富氟机理的研究进展

富氟异常是南极磷虾独特而有趣的生理性状,研究其富氟机理对于阐释极端环境下生物适应性进化机制,功能性仿生材料设计及磷虾的高值化利用具有重要意义。本文对南极磷虾富氟机理的国内外研究进展进行了评述,评述内容包括氟的来源、氟在磷虾中的分配特征和赋存形态、氟在磷虾体内的变化特征分析以及磷虾富集氟的模式推测等,并对南极磷虾富氟机理今后的研究方向和趋势进行了展望。     

Stars, galaxies, cosmos: the past decade, the next decade

Our perception of the universe has been altered by recent discoveries in astronomy, discoveries of new objects and of new phenomena, coming from a wide range of observing techniques. By 1990 astronomers expect to know more about the distribution of mass in the universe, the physics of energetic sources, and the intricate interconnections of astrophysical processes on a variety of spatial and temporal scales.     

Hotspots, basalts, and the evolution of the mantle

The trace element concentration patterns of continental and ocean island basalts and of mid-ocean ridge basalts are complementary. The relative sizes of the source regions for these fundamentally different basalt types can be estimated from the trace element enrichment-depletion patterns. Their combined volume occupies most of the mantle above the 670 kilometer discontinuity. The source regions separated as a result of early mantle differentiation and crystal fractionation from the resulting melt. The mid-ocean ridge basalts source evolved from an eclogite cumulate that lost its late-stage enriched fluids at various times to the shallower mantle and continental crust. The mid-ocean ridge basalts source is rich in garnet and clinopyroxene, whereas the continental and ocean island basalt source is a garnet peridotite that has experienced secondary enrichment. These relationships are consistent with the evolution of a terrestrial magma ocean.