Additional chromosome duplication in female meiotic prophase ofSipyloidea sipylus Westwood (Insecta,Phasmida), and its absence in male meiosis

Summary In the parthenogenetic stick insectSipyloidea sipylus, an additional chromosome duplication takes place in the primary oocytes immediately after pachytene. After duplication, the chromosomes again appear in a pachytene configuration, and oogenesis proceeds with twice the somatic number of chromosomes. Additional duplication does not occur during prophase of primary spermatocytes.     

Bemerkungen zur Struktur des Capsorubins

Summary By oxidative degradation of capsorubin, it could be demonstrated that the methyl groups are in position 1, 1, 5 (1, 1, 5) and the OH-group is attached to carbon atom 3 (3). An analogous structure may be assumed for capsanthin and cryptocapsin.     

Glycogen in epidermal nerve terminals of Lacerta sicula (squamata: reptilia).

Proof is given that the granula occuring in the epidermal discoid nerve terminals of Lacerta sicula consist of glycogen. Staining with PA-PbCi shows 300 A sized alpha-particles and 70 A sized beta-particles. The electron-dense boundary appearing after digestion with alpha-amylase consists of limit-dextrins.     

Influence des stimulations auditives sur le comportement sexuel du taureau

Summary In a preliminary series of experiments, it was noted that dairy bulls who refused to mount the cow for a long time, could be induced to mount it again when acoustically stimulated by specific calls of cows emitted by a magnetophone. In these conditions, the reaction time of the bulls was also shorter, while ejaculated quantities did not differ from those obtained before the experiments. It is suggested that this rather simple procedure could be helpful when the use of bulls as teasers raises difficulties.     

Genomic analysis of Bartonella identifies type IV secretion systems as host adaptability factors

The bacterial genus Bartonella comprises 21 pathogens causing characteristic intraerythrocytic infections. Bartonella bacilliformis is a severe pathogen representing an ancestral lineage, whereas the other species are benign pathogens that evolved by radial speciation. Here, we have used comparative and functional genomics to infer pathogenicity genes specific to the radiating lineage, and we suggest that these genes may have facilitated adaptation to the host environment. We determined the complete genome sequence of Bartonella tribocorum by shotgun sequencing and functionally identified 97 pathogenicity genes by signature-tagged mutagenesis. Eighty-one pathogenicity genes belong to the core genome (1,097 genes) of the radiating lineage inferred from genome comparison of B. tribocorum, Bartonella henselae and Bartonella quintana. Sixty-six pathogenicity genes are present in B. bacilliformis, and one has been lost by deletion. The 14 pathogenicity genes specific for the radiating lineage encode two laterally acquired type IV secretion systems, suggesting that these systems have a role in host adaptability.     

构造、地貌和气候对汶川地震同震及震后地质灾害的控制作用——以龙门山北段通口河流域为例*

通过对汶川地震驱动的通口河流域同震崩塌、滑坡等地质灾害的野外实地考察和遥感影像分析,获得通口河流域同震及震后地质灾害的空间分布情况,结合对通口河流域构造、地貌和气候等因素的分析,获得以下认识：（1）构造因素（汶川地震）是导致通口河流域同震地质灾害的根本原因;（2）地貌因素为同震及震后地质灾害的发生提供了重要的环境条件;（3）以降雨为主的气候因素是导致震后通口河流域地质灾害发生的直接诱发因素。