安全科学管理与人为失效研究——分析铁路运输中的人为失效规律

本文论述了安全科学中的人为失效理论与实践问題,即理论上研究了作为一门独立的人为安全学的基本范畴及框架,实践上分析了北京铁路分局某站近30年的事故情况,还探讨了减少人为事故对铁路安全运输的意义、作用及实施对策。     

MIEX~预处理对水源水中藻源DON的去除效能及机理

利用小试试验研究了磁性离子交换树脂预处理(MIEX~)对高藻水源水中的溶解性有机氮(DON)的去除效能,并通过分子量分布测定、双向电泳等手段初步分析了其作用机理.结果表明,MIEX~预处理对DON具有较好地去除效果,并可有效强化混凝工艺的处理效能.投加量为15m L/L时,MIEX~预处理可提升DON去除率20%;以铜绿微囊藻为主要种属的高藻水源水中藻类蛋白种类不低于230种,且大多数处于酸性端,分子量区间主要分布于15~40Ku、65~75Ku,处于MIEX~预处理可去除的分子量区间,从而具有较好的去除效果.综上所述,MIEX~预处理可以作为强化去除高藻水源水中DON的一种方法.     

The characteristic of in situ stress in outburst area of China

In order to obtain the characteristics of in situ stress field in outburst mining area, using the hollow inclusion (HI) technique to measure the in situ stress of coal and gas outburst mining area. The measurement sites located in northeast, middle and east of china, which include eight mining areas such as Fuxin, Pingdingshan, Hebi and Huainan. Base on the analysis of measurement data from outburst mining area, conclusions could be obtained as follow: (a) major principal stress and minor principal stress is horizontal stress and interim principal stress is vertical stress, and the type of outburst area’s stress field is dynamic stress field; (b) the major principal stress and minor principal stress are higher than other regions and the tectonic stress is outstanding; and (c) the ratio of major principal and vertical stress is decrease with the increase of depth and the type of stress field is likely transfer dynamic to static. Thus, in situ stress plays a key role during the occurring and development of coal and gas outburst, which is an important reason of severe outburst in China.     

细胞凋亡的线粒体途径调控

细胞凋亡是近年来研究的一个热点问题，涉及到细胞内许多复杂的生化过程．线粒体是真核生物能量和代谢的中心，也是细胞凋亡信号传导途径中起关键调节作用的细胞器，对细胞凋亡的线粒体途径调控机制进行研究具有重要意义．本文综述了细胞凋亡过程中线粒体途径的信号传导及其调控机制、线粒体对细胞凋亡信号的反应、细胞凋亡过程中线粒体功能丧失几方面的研究进展．图1参43     

Kinship, familiarity and social status modulate social learning about “micropredators” (biting flies) in deer mice

Animals can learn to recognize and respond to dangerous, threatening factors through either individual or social learning, whereby an individual learns and acquires the defensive behaviors and avoidance responses of another. Here we show that kinship, familiarity, and relative dominance of the interacting individuals affect social learning of defensive responses to micropredators in deer mice, Peromyscus maniculatus. Brief exposure of individual male deer mice to biting flies (stable fly, Stomoxys calcitrans) induced a decrease in pain sensitivity, or analgesia, and active self-burying avoidance responses. The defensive analgesic responses and their fear/anxiety/stress associated correlates facilitate the display of behavioral avoidance responses. Preparatory analgesia and avoidance responses were evident 1–3 days later when the mice were exposed to biting flies that were altered to be incapable of biting but were not displayed to similar-sized non-biting house flies. These anticipatory avoidance and analgesic responses to biting flies were also acquired through social learning—without direct individual aversive experience with biting flies. Fly-naive mice (observers) that witnessed other mice (demonstrators) being attacked by biting flies but themselves were not bitten did not display any avoidance responses. However, when exposed 1–3 days later to altered flies with biting mouth parts removed, the observers displayed socially acquired analgesic and self-burying avoidance responses. Observers whose demonstrators were either kin (siblings) and, or members of a familiar pair (kin or non-kin) displayed enhanced social learning of defensive responses. Also, within the familiar pairs, social status affected learning with subordinate observers displaying better social learning than dominant observers. These findings indicate that kinship, familiarity and social status modulate social learning of defensive responses to, and the recognition of, dangerous and threatening stimuli, likely including that of predators.Communicated by G. Wilkinson     

板料拉延成形中应力状态的研究

在采用Hill关于各向异性材料的修正屈服函数,并运用板块分析方法对板料轴对称成形进行数值模拟的基础上,着重分析了拉延成形中悬空区域材料的应力状态,提出了对该区域应力状态过渡点即周向应力为零的应力分界圆进行数值求解的公式及方法,同时对影响该分界圆位置的诸因素进行了细致分析.     

Cytoprotective and anti-apoptotic action of HSP70 stress protein in Oreochromis niloticus exposed to residual dilutions of insecticides with fipronil and ethiprole

Abstract

The objective of this research was to investigate the potential damage caused by the residual concentrations of the insecticides Regent^® WS 800 and Curbix^® SC 200, containing fipronil and ethiprole, respectively as active ingredients, on the liver of Oreochromis niloticus. The analyses of HSP70 shock protein labelling and cell death process by TUNEL method were performed in order to measure the effects of the exposure of cell repair system of fish to both insecticides. Statistical analyses showed no significant molecular damage to the hepatic tissue of animals. Nevertheless, variations in HSP70 and DNA fragmentation levels, endpoint of cell repair system response and cellular death, respectively, were observed in several groups. These results indicate that the cell repair machinery was efficient when in contact with residual concentrations of insecticides. However, the DNA fragmentation detected by the TUNEL method suggests that even in face of the cytoprotective action of the HSP70 protein, there are damages that become irreparable. To finish, it is worth mentioning that given the results obtained from residual concentrations, use in the field should be with caution.