Effect of benzo(a)pyrene exposure on the testis maturity of male cuvier

本实验采用雄性褐菖鲉作为实验对象,腹腔注射0.5×10-6、1×10-6、5×10-6、10×10-6(m/m)苯并[a]芘,7d后苯并[a]芘处理组精巢睾酮水平和睾酮与17β-雌二醇的比值都有上升,但都未表现出显著性差异(P>0.05).腹腔注射50×10-6(m/m)苯并[a]芘,11d后取出精巢,常规石蜡切片,结果显示雄性褐菖鲉的精巢,精小叶腔和输出管中精子密集程度明显增加,次级精母细胞减少,精巢壁厚度变薄.结果提示,苯并[a]芘对褐菖鲉具有类雄激素效应.In this experiment,intraperitoneal injections of benzo(a)pyrene(BaP) [0.5×10~(-6),1×10~(-6),5×10~(-6),10×10~(-6)(m/m)] were given to male cuviers.7 days after the injections,levels of testosterone and testosterone/17β-estradiol in exposure groups increased,but there are no significant difference(P>0.05) between the exposure groups and the control.An intraperitoneal injection of BaP [50×10~(-6)(m/m)] was given to cuvier.11 days after the injection,testis samples were collected,dealed with common tissue section.It was observed that the density of sperm in lobular lumen and vas efferens was increased distinctly.The secondary spermatogonium was decreased.The testis wall in TBT-treated group became thiner than the control.The result indicated BaP has an androgen effect on cuvier.国家自然科学基金资助项目(40476049);; 近海海洋环境科学国家重点实验室(厦门大学)基金资

光敏性溶胶-凝胶波导材料

采用有机改性硅酸盐制备了光敏性溶胶-凝胶,并应用四丙氧基锆作为调节折射率的材料.为了增加薄膜与硅片的粘附作用,先用干氧热氧化法在硅片上生长一层厚度约为150nm的SiO2,然后使用提拉法在硅片上提拉成膜,薄膜厚度达到3.6μm.研究发现紫外曝光时间和坚膜时的后烘温度都会使薄膜的折射率增大.样品的原子力显微镜照片表明薄膜的表面非常平整,在5μm×5μm的范围内表面起伏只有0.657nm.利用波导阵列掩膜版,对制备的薄膜在紫外光波段下曝光,得到了表面平坦、侧墙光滑、陡直的沟道波导阵列

溶胶-凝胶法制备光波导薄膜及性质的研究

采用有机改性硅酸盐制备了光敏性溶胶-凝胶,并在凝胶中加入四丙氧基锆作为调节折射率的材料;用该凝胶在硅片上提拉成膜.为了增加薄膜与硅片的粘附性,成膜前先用干氧热氧化法在硅片上生长了一层厚度约为1500的二氧化硅;样品的原子力相片表明薄膜的表面非常平整,在5×5 μm2的范围内最大表面起伏只有0.657 nm.利用波导阵列掩膜版, 对制备的薄膜在紫外光波段下曝光,得到了表面平坦、侧墙光滑、陡直的沟道波导阵列.研究发现:紫外曝光时间和坚膜时的后烘温度都会使薄膜的折射率增大.通过对样品红外吸收谱的分析,从微观机理上解释了折射率随工艺条件变化的原因

Predation Strategies of Four Common Crabs on Sea Urchins Mesocentrotus nudus with Different Sizes

[Objectives] Mesocentrotus nudus is a key species in maintaining the stability of the kelp ecosystem and a valuable economic sea urchin species in northern China. However, little researches focus on its population ecology, and the factors impacting the population dynamics are still not clear. Gaetice depressus, Hemigrapsus sanguineus, Portunus trituberculatus and Charybdis japonica are four common crab species off the coast of China and are potential predators of M nudus. In order to explore the predation strategies and predation intensities of four crab species and the predation selectivities of C. japonica on different sizes of M. nudus, three different groups of body sizes of M nudus individuals, e.g., small sized (12 - 15 mm), medium sized (19-22 mm) and large sized (30 - 33 mm in diameter) were selected as the research objects. [Methods] Two sets of experiments were conducted in the laboratory. In the predation strategies and predation intensities experiment, each species of crabs was divided into two groups separately containing small and medium sized sea urchins, while the predation selective experiment contains a C. japonica and three sizes of urchins in a single experimental group. The data was analyzed using Excel and Spss16.0,and the significance was inspected using one-way ANOVA and Kruskal-Wallis in both sets of experiment, and Ivlev indexes were calculated to examine the predation selectivity of C. japonica on small and medium sized sea urchins. [Results] The results showed that four crab species could prey on the small sized sea urchin individuals, of which, the P. trituberculatus and C. japonica showed higher predation intensity on sea urchins (8.67 1.53 and 9.33 1.15, respectively, Table 2); whereas only P. trituberculatus and C. japonica consumed the medium sized sea urchins (Table 2). As for the predation strategies, four crab species presented diverse kinds of strategies on different sizes of sea urchins but showed similar predation behavior when encountering difficulties of crushing the urchins (Fig. 1). The predation and selection pattern of C. japonica belong to a kind of passive selection, and the selectivity was closely related to the size of its cheliped. Crabs with smaller cheliped had relatively high selective feeding index on small sized sea urchins (Fig. 2), while individuals with bigger cheliped showed no significant differencein predation rate for small and medium size sea urchins (one-way ANOVA, P > 0.05) (Fig. 2). [Conclusion] This study reveals that G. depressus, H. sanguineus, P. trituberculatus and C. japonica are all potential predator of sea urchin M. nudus. Moreover, they can adapt their hunting strategies according to the preys with different body size, predation capacity is a key factor to the prey selectivity of C. japonica