居群遗传学原理及其在珍稀濒危植物保护中的应用

居群遗传学在珍稀濒危植物保护研究中有着重要的应用价值。本文首先介绍了居群遗传学中的几个重要概念──有效居群大小、近交繁殖、遗传漂变和基因流，然后详细叙述了居群遗传学原理在珍稀濒危植物保护中的应用途径和前景。

广东惠州发现深圳香荚兰

报道了中国兰科Orchidaceae香荚兰属Vanilla的新报道种——深圳香荚兰Vanilla shenzhenica Z.J.Liu et S.C.Chen在广东惠州的分布,对该种的形态以及在新分布地的居群大小、生境和伴生植物等做了详细描述.

中国兰科兜兰属一新记录种——白旗兜兰

报道了中国兰科Orchidaceae兜兰属Paphiopedilum的一新分布种——白旗兜兰Paphiopedilumspicerianum(Rchb.f.)Pfitzer,对该种的形态以及在新分布地的居群大小、生境和伴生植物等做了详细描述。白旗兜兰由于人为采挖而变得十分稀少,建议尽快对该新分布地进行保护。

Consensus of Flocks under M-Nearest-Neighbor Rules

This paper investigates a class of flocks with an M-nearest-neighbor rule,where each agent's neighbors are determined according to M nearest agents with M being a given integer,rather than all the agents within a fixed metric distance as in the well-known Vicsek's model.Such a neighbor rule has been validated by biologists through experiments and the authors will prove that,similar to the Vicsek's model,such a new neighbor rule can also achieve consensus under some conditions imposed only on the system's speed and the number M,n,without resorting to any priori connectivity assumptions on the trajectory of the system.In particular,the authors will prove that if the number M is proportional to the population size n,then for any speed v,the system will achieve consensus with large probability if the population size is large enough.