ABSTRACT

The subject of this study is the structure and composition of buried Phoebe zhennan wood. Through comparative studies of the anatomy and composition with modern undegraded wood, the objective was to understand any changes that have taken place in the P. zhennan buried wood samples. The P. zhennan buried wood can be identified by wood structure characteristics and volatile components analysis. It is required that the microstructural features are identical to those of modern P. zhennan wood; simultaneously, the volatile components of the wood must contain six characteristic compounds with the same peak retention time. The P. zhennan buried wood sample which was used in the experiment was dated 8035–7945 BP (95. 4% probability). Further research showed that the cell wall of P. zhennan buried wood had been damaged, the hemicellulose was heavily degraded but there was no obvious degradation of crystalline cellulose. Moisture was present mainly as free water and large amounts of mineral elements such as Fe, and Ni were detected in the ash of P. zhennan buried wood. Both the buried and modern wood of P. zhennan were acidic.

In: IAWA Journal

Mifepristone and quinestrol are effective drugs for controlling rodent fertility, but their inhibitory effectiveness during premating, early pregnancy, and late pregnancy is unknown. In this study, six groups of eight female Brandt’s voles (Lasiopodomys brandtii) were administered with mifepristone, quinestrol, or a control for three days during premating, early pregnancy, or late pregnancy. In the mifepristone-treated groups, the premating females bred, whereas the early and late pregnant females did not. The reproductive rate, litter size, average body mass at birth, and survival rate of pups did not significantly differ between the mifepristone-treated premating group and the control group. By contrast, quinestrol treatment completely inhibited fertility during the three reproductive phases. In addition, fertility was not completely restored in the second pairing. The reproductive rates were higher for mifepristone, both during early and late pregnancy, than for quinestrol, but both were lower than the control. Thus, mifepristone and quinestrol both inhibited the fertility of female Brandt’s voles at different reproductive periods. These results suggest that these two sterilants could be delivered during the reproductive season of the target pest animal.

In: Animal Biology