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21.
Flubendiamide, a comparatively new insecticide, is used against lepidopteran insect pests and presumed safe for non-target Drosophila melanogaster (D. melanogaster). In this study, treatment concentrations (0.5, 1, 2 5, 10, and 20 μg/ml) of flubendiamide, lower than agricultural concentrations (rice 50μg/ml or cotton 100 μg/ml), were able to inhibit acetylcholinesterase activity in third instar larvae of D. melanogaster indicating a neurotoxic potential. In addition, larvae exposed to flubendiamide also manifested increased amounts of stress protein hsp70. The larvae expressing such stress response when allowed to emerge as adults displayed severe eye structure deformities found by scanning electron microscopy. These findings indicate a toxic potential for flubendiamide in D. melanogaster.  相似文献   
22.

Objective

The objective of this study was to evaluate repeated patient handling injuries following a multi-factor ergonomic intervention program among health care workers.

Methods

This was a quasi-experimental study which had an intervention group and a non-randomized control group. Data were collected from six hospitals in Saskatchewan, Canada from September 1, 2001 to December 1, 2006.

Results

A total of 1,480 individuals who had a previous injury were eligible for the study. Medium and small size hospitals in the intervention group had significantly fewer repeated injuries than in the control group. Multivariate analysis showed that the intervention group had 38.1% lower odds of having repeated injury compared to the control group, after adjusting for hospital size.

Conclusions

The work-related repeated injury after a multi-factor intervention program was reduced. The synergistic relationships between components of multi-factor intervention and applicability of injury prevention programs to different settings need to be further explored.

Impact on Industry

Implementing a multi-factor program with the right equipment and training can lower the risk of injury among health care workers.  相似文献   
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Regional variation in PCBs and organochlorine (OC) pesticide concentrations was examined using the blubber of 155 minke whales (Balaenoptera acutorostrata) sampled in seven regions in the North Atlantic and European Arctic, including western and southeastern Greenland, the Norwegian Sea, the North Sea and the Barents Sea. The levels and relative proportions of OCs were also used to examine the boundaries for North Atlantic minke whale stocks previously defined by the International Whaling Commission (IWC). Concentrations of major OC groups (sigmaPCB, 89.1-22 800 ng/g lipid; sigmaDDT, 65.3-6280 ng/g lipid; sigmaCHL, 33.3-2110 ng/g lipid) generally increased from west to east, while HCH concentrations (sigmaHCH, < 1-497 ng/g lipid) showed the opposite trend. Statistical comparison between six regions using sex-adjusted least squared mean concentrations showed that minke whales from the Barents Sea had significantly higher concentrations of EPCBs than those from the Vestfjorden/Lofoten, the North Sea, and west Svalbard, as well as significantly higher sigmaDDT concentrations compared to west Greenland animals. The differences in concentrations suggest that west and southeast Greenland minkes may represent one group of whales, which are distinct from both the Jan Mayen minkes and those from other IWC defined stocks in northern European waters. Principal components analysis using proportions of 71 PCB congeners and 20 OC pesticides (of total OCs) did not reveal any major differences among groups although minkes from the North Sea were distinguished from those from Greenland waters by higher loadings of more highly chlorinated PCBs and recalcitrant OC pesticides. The general similarity in mean levels of sigmaPCBs, sigmaDDT and sigmaCHL, as well as mean principal components analysis scores, among minkes sampled at Jan Mayen, Svalbard, Vestfjorden/Lofoten, the North Sea and the Barents Sea suggests that the whales are quite mobile and may feed in multiple areas within the northeastern Atlantic.  相似文献   
24.
 常温下用水解法处理BF4-废水.实验采用铝盐作主水解剂,试剂A作助水解剂,pH值小于3,在常温条件下实现了对BF44-的高效水解.研究结果表明,BF4-∶Al3+∶A的质量比为1∶0.8∶0.1,水解时间6~3h,水解率达到99.5%以上.使用助水解剂A,缩短了水解时间,减少了铝盐用量,对高浓度的BF4-废水效果尤为显著,水解时间可缩短一半,主水解剂用量可减少1/5,处理后出水中的BF4-含量可降到10mg/L以下.  相似文献   
25.
It is generally accepted that viral particles in source water are likely to be found as aggregates attached to other particles. For this reason, it is important to investigate the disinfection efficacy of chlorine on aggregated viruses. A method to produce adenovirus particle aggregation was developed for this study. Negative stain electron microscopy was used to measure aggregation before and after addition of virus particles to surface water at different pH and specific conductance levels. The impact of aggregation on the efficacy of chlorine disinfection was also examined. Disinfection experiments with human adenovirus 2 (HAdV2) in source water were conducted using 0.2 mg/L free chlorine at 5 °C. Aggregation of HAdV2 in source water (≥3 aggregated particles) remained higher at higher specific conductance and pH levels. However, aggregation was highly variable, with the percentage of particles present in aggregates ranging from 43 to 71 %. Upon addition into source water, the aggregation percentage dropped dramatically. On average, chlorination CT values (chlorine concentration in mg/L × time in min) for 3-log10 inactivation of aggregated HAdV2 were up to three times higher than those for dispersed HAdV2, indicating that aggregation reduced the disinfection rate. This information can be used by water utilities and regulators to guide decision making regarding disinfection of viruses in water.  相似文献   
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Demersal fish cannot readily be tracked using satellite-based or light-based geolocation techniques. As an alternative, we describe the tidal location method, which uses tidal data recorded by electronic data storage tags (DSTs), to determine geoposition. Times of high water (H) and tidal ranges (R) recorded by DSTs moored at known locations, and from free-swimming tagged plaice, Pleuronectes platessa, were compared with a North Sea tidal database to identify all positions with matching values of H and R. Within the recording precision of the tag (ǂ.2 m, ᆞ min) and the predicted accuracy of the model generated tidal data (ǂ.15 m, ᆨ min), geolocations over much of the North Sea and eastern English Channel were predicted to be accurate to within 40 km, sometimes to within 10 km. Positional estimates of the moored tags were within 15.7Dž.5 km of the actual locations. Geolocations made from tagged plaice within 5 days of release and 5 days pre-recapture were within 35ᆬ km and 37ᆫ km of release and recapture positions respectively. Our results demonstrate the ability of this method to accurately describe the migrations of North Sea plaice throughout their geographical range with a level of accuracy unattainable using light-based geolocation. The method could equally be applied to any shelf-dwelling demersal fish that periodically rests on the sea-bed for the duration of a tidal cycle. In fisheries management, the method has clear potential application in defining the movements and migrations of other commercial species.  相似文献   
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Urban displacement is frequently portrayed as a new and unfamiliar dilemma for the humanitarian sector, yet broad awareness of its characteristics and challenges has been developing since the 1970s. In the past decade, however, there has been greater attention to, and recognition of, the implications of rapid urbanisation in the developing world. This has led to some policy development and a mounting body of NGO (non-governmental organisation) and think-tank literature on the topic. Assuming displacement to be a key lens on urban vulnerability more broadly, this paper presents an overview of the historical development of debates on urban displacement since the 1970s. Drawing examples from the contributions in this special issue of Disasters, as well as from other sources of information on recent humanitarian responses in various contexts, it assesses the ramifications of urban vulnerability for humanitarian practitioners. The paper contends that the humanitarian sector has failed to galvanise on the issue, and has struggled therefore to employ existing knowledge and to adapt practice.  相似文献   
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