Polymorphism and heredity of cpDNA and mtDNA in the Section Leuce of Populus

The chloroplast DNA （cpDNA） and mitochondrial DNA （mtDNA） of 16 Populus species （Section Leuce） and their F1 generation were detected using PCR-RFLP technique. The results show that cpDNA in the F1 generation of 22 hybrid combinations was inherited maternally, which supported the conclusions of the study of plasmid cytology. The mtDNA fragments amplified by PCR were consistent with the restriction maps in all hybrid combinations and no polymorphism was detected, indicating that the Section Leuce is highly conserved in mitochondrial gene sequences. These results provided direct evidence of maternal chloroplast inheritance in Populus tomentosa, P. bolleana, P. davidiana, P. adenopoda, P. tomentosa × P. bolleana, P. alba × P. glandulosa and P. alba × P. tomentosa.

基于网络生命周期的节能非均匀分簇路由算法

针对在大规模地下隧道中应用无线传感网络的问题,在保证数据可靠传输的前提下,提出一种基于网络生命周期的非均匀分簇路由协议LEUC。为有效解决大规模网络问题,在长形隧道里建立环形节点模型,以一个基站及其覆盖节点进行分块传输。LEUC协议采用基于节点剩余能量和簇半径的簇头竞争算法,完成了非均匀分簇。距离基站较近的地方拥有较多的簇头,以承担转发数据所消耗的能量。仿真实验结果表明,LEUC实现了有效的分簇结构,提高了能量效率,延长了网络生命周期。