FIELD-LABORATORY DETERMINED AVOIDANCES OF THE SPOTFIN SHINER AND THE BLUNTNOSE MINNOW TO CHLORINATED DISCHARGES1

ABSTRACT: The responses of the spotfin shiner (Notropis spilopterus) and bluntnose minnow (Pimephales notatus) to intermittent chlorine discharges from a fossil fuel power plant in the New River were investigated by seine collections in the chlorinated discharge channel, and chlorine avoidances were obtained in a field laboratory at the power plant in Glen Lyn, Virginia. No fish were captured by seine during chlorination periods when the total chlorine (TCR) and free chlorine (FCR) residuals were, respectively, 0.46 and 0.27 mg/1 or higher at river water temperatures of 12 C or less. For collections made between eight-hour chlorination periods, the number of fish was reduced by approximately 50% at 0.20 and 0.06 mg/1 TCR and FCR, respectively. Significant (0.05 level) laboratory avoidances occurred at 0.10 to 0.20 mg/1 TCR (0.03 to 0.14 mg/1 FCR) for both species when exposed to increasing TCR concentrations of 0.10, 0.20, 0.30 and 0.40 mg/1. Responses varied with acclimation temperature (6, 12, 18 and 24 C) with no consisteent trends between species. When exposed to a constant TCR concentration during any one test (0.14, 0.18 and 0.26 mg/1 for the spotfin shiner, and 0.11 and 0.17 mg/1 for the bluntnose minnow), significant avoidances were observed at 0.26 and 0.17 mg/1 for each species, respectively. In all laboratory trials, occurrence or residence times decreased with increasing chlorine concentration, with residence times as high as 64.7% at 0.10 mg/1 TCR and as low as 8.3% at 0.40 mg/1 being observed.     

Evaluation of joint toxicity of heavy metals and herbicide mixtures in soils to earthworms (Eisenia fetida)

It is widely acknowledged that a simplified and robust approach to evaluating thecombined effects of chemical mixtures is critical for ecological risk assessment (ERA) of contaminated soil. The earthworm (Eisenia fetida) was used as a model to study the combined effects of polymetallic contamination and the herbicide siduron in field soil using a microcosm experiment. The responses of multiple biomarkers, including the activities of catalase (CAT), superoxide dismutase (SOD), glutathione reductase (GR) and acetylcholine esterase (AChE), the concentrations of glycogen, soluble protein (SP), malonaldehyde (MDA), and metallothionein (MT), and the neutral red uptake test (NRU), were investigated. Multivariate analysis, Principal Component Analysis (PCA) and Spearman's Rank Correlations analysis (BVSTEP) revealed that the activities of AChE and CAT and the NRU content were the prognostic biomarkers capturing the minimum data set of all the variables. Internal Cd (tissue Cd) in earthworms was closely related to the health status of worms under combined contamination of heavy metals and siduron. The integrated effect (E_mix) calculated based on the activities of AChE and CAT and NRU content using the stress index method had significantly linear regression with internal Cd (p<0.01). E_mix(10), E_mix(20), and E_mix(50) were then calculated, at 1.27, 1.63 and 2.71 mg/kg dry weight, respectively. It could be concluded that a bioassay-based approach incorporating multivariate analysis and internal dose was pragmatic and applicable to evaluating combined effects of chemical mixtures in soils under the guidance of the top-down evaluation concept of combined toxicity.     

安装有防屈曲支撑建筑的地震模拟与经济性分析

结合防屈曲支撑拟静力实验的研究成果,用ABAQUS有限元软件模拟一栋建筑的地震反应。比较原设计结构与减少梁柱面积但安装有防屈曲支撑的减缩结构这2种方案下的地震响应,使两者的层间位移角相近并满足规范要求,进而做经济性对比。结果表明,防屈曲支撑可以有效地减小结构地震响应,并且先于梁柱破坏,保护主体结构安全;安装防屈曲支撑的结构在满足设计要求的同时,还可以节省建筑成本,缩短施工工期。     

PFOA对斑马鱼胚胎发育、行为和DNA损伤的毒性研究

全氟辛酸(PFOA)是一种分布广泛的环境持久性有机污染物,在野生动物与人体内普遍被检出。目前PFOA发育毒性的特点和机制尚未阐明,已有的研究显示,PFOA毒性与受试物种及性别密切相关。因此,利用不同物种进行PFOA毒性研究对阐明其毒性机制十分重要。本研究选用了斑马鱼这种理想的脊椎动物模型,考察了PFOA暴露对其胚胎发育的自主运动、心跳、行为、细胞凋亡和DNA损伤的影响。研究发现,始于6hpf的PFOA暴露会导致斑马鱼胚胎自主运动异常,心率降低,且具有一定的剂量依赖性;6～24hpf的高浓度的PFOA暴露(>414.0mg·L-1)会导致胚胎发生显著的细胞凋亡,凋亡主要出现在眼部、头部、心脏和尾部。较高浓度的PFOA暴露(165.6mg·L-1)会使仔鱼的光刺激应激行为模式发生变化。此外,PFOA暴露会致使斑马鱼发生DNA损伤,且损伤程度随PFOA浓度的升高而加重,表明PFOA具有一定的基因毒性。上述结果表明,PFOA对斑马鱼胚胎具有发育毒性,具体表现为自主运动异常,心率降低和行为反应能力变弱,同时伴随畸形、细胞凋亡和DNA损伤。     

北部湾文蛤对石油烃和多氯联苯的氧化应激响应

为探讨海域现场双壳类动物对有机污染物积累的抗氧化响应,在北部湾潮间带11个采样点采集文蛤(Meretrix meretrix)样品,测定其软组织中w(TPHs)(TPHs为石油烃)、w(PCBs)(PCBs为多氯联苯)以及鳃、内脏中GSH(还原型谷胱甘肽),GSSG(氧化型谷胱甘肽)、SOD(超氧化物歧化酶)、CAT(过氧化氢酶)、GPx(谷胱甘肽过氧化物酶)、GST(谷胱甘肽转硫酶)、TBARS(硫代巴比妥酸反应物)7种氧化应激物的水平,分析其空间分布特征,并进行有机污染物含量与氧化应激物响应值之间的相关性分析. 结果表明:文蛤软组织中w(TPHs)和w(PCBs)分别为78.22~300.71μg/g和4.23~26.68ng/g,最大值均出现在S10采样点(防城港西湾);内脏中CAT活性较高,其他氧化应激物均在鳃中有较高水平. 与对照采样点S1(湛江流沙湾)相比,S2、S3、S6、S10、S11等5个采样点文蛤组织内SOD、CAT、GST、GPx、GSH水平较低;大多数采样点文蛤鳃中w(GSSG)较低,而S3、S4、S6、S7、S9、S11等6个采样点文蛤内脏中w(GSSG)较高;大多数采样点文蛤组织中TBARS含量较低,表明其抗氧化防御机能尚未丧失. TPHs显著抑制文蛤鳃中的w(GSSG) (R=-0.64,P<0.05),PCBs显著抑制文蛤鳃中的GPx(R=-0.72,P<0.05)和GST(R=-0.72,P<0.05)的活性,表明w(GSSG)及GPx和GST的活性可作为指示北部湾有机污染的生物标志物.      

Investigating the potential for different scooter and car exhaust emissions to cause cytotoxic and (pro-)inflammatory responses to a 3D in vitro model of the human epithelial airway

The aim of this study was to compare the cytotoxicity and the (pro-)inflammatory responses of two-stroke (direct injection and carburetor technology) and four-stroke scooter and diesel car exhaust emissions on lung cells in vitro. This was analyzed by exposing a 3D in vitro model of the epithelial airway (consisting of human bronchial epithelial cells (cell line 16HBE14o^?) combined with human whole blood monocyte-derived macrophages and dendritic cells) to physically characterized exhaust emissions. Biological endpoints of cytotoxicity (lactate dehydrogenase release), as well as pro-inflammatory cytokine (tumor necrosis factor (TNF)-α) and inflammatory chemokine (interleukin(IL)-8) stimulation were examined. Two-stroke direct injection scooter exhaust contained the highest particle number concentration and nitrogen oxides (NO _x ) concentrations and the emissions from the two-stroke carburetor scooter contained the highest hydrocarbon and lowest NO _x concentrations. The four-stroke scooter emitted the highest carbon monoxide concentration whereas the cars emitted the lowest. The combination of various technical optimizations for the two-stroke direct injection scooter (particle filter, oxidative catalyst, better oil and fuel) reduced the total emissions strongly and the TNF-α concentration significantly (p?相似文献   

镉胁迫对拟南芥中氨基酸及其衍生物的影响

研究拟南芥对镉胁迫的氨基酸及其衍生物响应.结果表明,镉胁迫使大部分检测到的化合物发生变化,并且在不同镉浓度情况下(Cd5和Cd50)显示了共同的响应,只是响应幅度不同.同一代谢途径中的化合物含量变化具有相关性:α-酮戊二酸衍生类型(谷氨酸和谷氨酰胺)和草酰乙酸衍生类型(天冬氨酸和天冬酰胺)氨基酸含量都降低,除脯氨酸外;3-磷酸甘油酸衍生类型(丝氨酸和甘氨酸)氨基酸含量都增加;丙酮酸衍生类型的氨基酸(缬氨酸、亮氨酸和异亮氨酸)含量几乎没有变化;由莽草酸转化而来的酪氨酸含量降低,另外,镉胁迫诱导胺类(β-丙氨酸、4-氨基丁酸、腐胺和酪胺)化合物含量显著增加.     

论中国绿色投资管理

绿色投资是绿色经济发展的必然结果,绿色投资是绿色经济增长的第一推动力。绿色投资是最能体现以人为本和经济社会可持续发展的投资,是最能体现科学发展观的投资。从绿色投资的含义及与绿色经济的关联出发,在脱钩理论的基础上,分析了中国绿色投资的现状和问题,探讨了如何加大中国绿色投资,促进绿色经济发展,实现中国经济社会的可持续发展。     

The effect of artificial smoke compound on physiological responses,cognitive functions and work performance during firefighting activities in a smoke-diving room: an intervention study

This study investigated the combined effect of firefighting operations and exposure to smoke on physiological responses, cognitive functions and physical performance among firefighters. Each firefighter was engaged in two experimental conditions: (a) without artificial smoke, control (NS); (b) with artificial smoke (WS). The results of data analysis revealed that heart rate and body temperature increased significantly after the firefighting activities in the two conditions relative to baseline. In addition, reaction time (RT) and correct response (CR) decreased after the activity relative to baseline and there was a significant difference in RT and CR between the NS and WS conditions. There was also a significant difference in performance time between the NS and WS conditions. These findings demonstrated that a smoke compound has an insignificant effect on physiological responses during firefighting activity. On the contrary, the smoke compound has a detrimental influence on cognitive and physical performance.     

2种有机磷农药联合胁迫下日本青鳉的逐级行为响应

采用水质安全在线生物预警系统(BEWs)记录行为强度数据,探讨了2种有机磷农药敌百虫和对硫磷联合胁迫下,不同暴露浓度、不同暴露时间日本青鳉的行为响应.在不同浓度比例的农药暴露中,20、10、5、1和0.1TU的暴露浓度下行为反应时间分别为:1.4、4.8、6.4、32.2和43.0h,并且每个浓度不同配比之间行为反应时间差异不明显.结果表明,在2种有机磷农药的暴露下,日本青鳉的逐级行为响应既受化合物浓度高低的影响,又受暴露时间的影响,但每个浓度的不同配比之间的行为响应时间差异不明显,而且每个浓度2种药物不同配比暴露下的青鳉鱼的逐级行为响应基本一致,即2种作用机制相似的有机磷农药对日本青鳉的行为毒性是简单的相加作用.