Effect of gender on physiological and behavioural responses of Gammarus roeseli (Crustacea Amphipoda) to salinity and temperature

The importance of potentially interacting factors in organisms responses to a stress are often ignored or underestimated in ecotoxicology. In laboratory experiments we investigated how gender, temperature and age influence the behaviour and the physiology of the freshwater amphipod Gammarus roeseli under salinity stress. Our results revealed a significant higher sensitivity of females in survival, ventilation and ionoregulation whereas no inter-age differences were reported. Water temperature also exerted a significant effect in survival and ventilation of G. roeseli. Some of those factors appeared to interact significantly. This study provides evidence that gender can affect organisms responses to a stressor and consequently has to be considered while assessing a stress impact. We discussed the potential relationships between biological and behavioural responses.     

基于模糊层次分析法的应急能力评估方法探讨

对危险行业的安全生产事故应急能力进行安全评估，可以持续改进应急管理工作，提高事故应急能力的总体水平。作为综合性的安全评估方法，层次分析法在安全研究的多个领域中得到了应用。通过介绍安全生产事故应急管理能力及其评估要求，分析国内外应急能力评估的现状，提出了应急能力评估体系建立的总体思路。论述了事故应急能力评估指标集的建立方法和基于模糊层次综合评价法的评估模型构建方案，初步建立起事故应急管理能力评估方法。     

六自由度气锤振动技术与电磁斜面振动技术比较

六自由度气锤振动与电磁斜面振动是两种模拟产品三轴振动的振动技术。由于两种振动技术的机理不同，其对样品的振动影响也会有区别。本文研究讨论两种不同振动技术的不同特点，以及对不同产品的振动效果别，我们可以根据样品特点和测试需求，选择更合适的震动技术。     

交通荷载作用下饱和软粘土孔压-应变分析模型

针对交通荷载的作用特点设计了循环三轴试验,进而对交通荷载作用下饱和软粘土的动力特件进行厂研究.结果表明:循环荷载作用下,饱和软粘土存在临界循环应力比,采用孔压曲线所得到的临界循环应力比要小于采用应变曲线所得到的临界循环应力比.当土样不存在初始剪应力时,随着循环次数的增加,土样的应力-应变关系曲线近似原点对称,但随着初始剪应力的增大,应力-应变关系曲线逐渐表现为一系列平行曲线,峰值孔压与循环孔压幅值均逐渐减少;同时,轴应变的发展加快,但循环应变幅值逐渐减小.当循环应力比小于临界循环应力比时,对于同一初始剪应力,不同循环应力比下的孔压比-动应变曲线近似集中在同一条曲线上.通过对试验数据进行回归分析,得到了交通荷载作用下饱和软粘土残余孔压-累积塑性应变关系模型.     

Environmental Exposure of Aquatic and Terrestrial Biota to Triclosan and Triclocarban1

Abstract: The synthetic biocides triclosan (5‐chloro‐2‐(2,4‐dichlorophenoxy)phenol) and triclocarban (3,4,4′‐trichlorocarbanilide) are routinely added to a wide array of antimicrobial personal care products and consumer articles. Both compounds can persist in the environment and exhibit toxicity toward a number of biological receptors. Recent reports of toxicological effects in wildlife, human cell cultures, and laboratory animals have heightened the interest in the occurrence of these biocide and related toxic effects. The present study aimed to summarize published environmental concentrations of biocides and contrast them with toxicity threshold values of susceptible organisms. Environmental occurrences and toxicity threshold values span more than six orders of magnitude in concentration. The highest biocide levels, measured in the mid parts‐per‐million range, were determined to occur in aquatic sediments and in municipal biosolids destined for land application. Crustacea and algae were identified as the most sensitive species, susceptible to adverse effects from biocide exposures in the parts‐per‐trillion range. An overlap of environmental concentrations and toxicity threshold values was noted for these more sensitive organisms, suggesting potential adverse ecological effects in aquatic environments. Affirmative evidence for this is lacking, however, since studies examining environmental occurrences of biocides vis‐à‐vis the health and diversity of aquatic species have not yet been conducted.     

层次分析法的改进及在安全决策中应用的研究

本文根据化工行业的特点及调研资料，建立了影响安全的层次结构模型即安全指标体系。并利用改进式层次分析法（IAHP）对该体系进行分析，得出了各个因素对安全的影响系数（权重）。     

基于生态安全的DAT-IAT城市污水处理工艺改进研究

通过正交试验，得到了DAT-IAT工艺和A/DAT-IAT工艺处理城市污水的常规指标去除和生态毒理指标削减的最优运行条件。结果表明，在正交试验的同一工艺中，COD去除最优运行条件的出水COD值优于生态毒性削减最优运行条件的出水COD值，但前者出水的生态毒性较大。由于厌氧池的水解酸化作用，A/DAT-IAT工艺对COD和生态毒性的处理效果均优于DAT-IAT工艺，并且回流总能耗低于DAT-IAT工艺，但是出水COD仍不达标。为了降低进入工艺的COD的总量，以絮凝沉淀做为预处理工艺，并采用Al残留量最小的絮凝剂投药量以降低出水中残留Al带来的生态风险。结果表明，在COD去除最优运行条件下，具有絮凝预处理的工艺对COD的去除效果优于没有絮凝预处理的工艺。絮凝-A/DAT-IAT工艺在COD去除最优运行条件下出水COD为104.46 mg/L，满足排放标准。在毒性削减最优运行条件下，具有絮凝预处理的工艺的出水生态毒性有所上升，但是污染物的总量得到了大幅削减。絮凝-A/DAT-IAT工艺与DAT-IAT工艺相比，在污染物去除效率得到大幅增加的同时，生态毒性得到有效控制，生态安全得到了有效的保障。     

Accumulation of mercury and its effect on antioxidant enzymes in brain,liver, and kidneys of mice

Abstract

The effect of mercuric chloride (HgCl₂) on the activities of catalase, Superoxide dismutase (SOD), glutathione peroxidase (GPx), glutathione reductase (GR) and its effect on glutathione (GSH) content were evaluated in different organs (liver, kidneys, and brain) of mice after administration at 0, 0.25, 0.5 and 1.0 mg/kg/day for 14 days. The uptake of mercury shows that the kidneys accumulated the highest levels of mercury compare to brain and liver. The enzyme levels varied in mercury treated organs compare to control. A dose dependent increase of antioxidant enzymes occurred in the liver and kidneys. The increase in enzyme activities correlated with highest mercury accumulation in the kidneys and liver. Mercury is known to generate reactive oxygen species (ROS) in vivo and in vitro, therefore, it is likely that enzyme activities increased to scavenge ROS levels produced as a result of mercury accumulation. Glutathione content increased in liver and kidneys of mercury treated mice compare to control. The results showed that the highest oral dose of mercury significantly increased antioxidant enzymes in kidneys and liver. The increased antioxidant enzymes enhance the antioxidant potential of the organs to reduce oxidative stress.     

Cytotoxicity and DNA damage of five organophosphorus pesticides mediated by oxidative stress in PC12 cells and protection by vitamin E

Previous studies have demonstrated that pesticides could induce cytotoxicity and genotoxicity in vivo and in vitro, and that oxidative stress may be an important factor involved. However, investigations comparing the capability of different organophosphorous (OP) compounds to induce cytotoxicity, genotoxicity and oxidative stress are limited. Hence, the aim of this paper was to access the cytotoxic and genotoxic effects of five OPs or metabolites, Acephate (ACE), Methamidophos (MET), Chloramidophos (CHL), Malathion (MAT) and Malaoxon (MAO), and to clarify the role of oxidative stress, using PC12 cells. The results demonstrated that MET, MAT and MAO caused significant inhibition of cell viability and increased DNA damage in PC12 cells at 40 mg L^?1. MAO was more toxic than the other OPs. ACE, MET, MAT and MAO increased the levels of intracellular reactive oxygen species (ROS) and malondialdehyde (MDA), and decreased the activity of superoxide dismutase (SOD), catalase (CAT) and glutathione (GSH) at 20 mg L^?1 and 40 mg L^?1 to different degrees. Pre-treatment with vitamin E(600 μM)caused a significant attenuation in the cytotoxic and genotoxic effect; pre-treatment reversed subsequent OP-induced elevation of peroxidation products and the decline of anti-oxidant enzyme activities. These results indicate that oxidative damage is likely to be an initiating event that contributes to the OP-induced cytotoxicity.