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71.
72.
City bus drivers spend hours driving under time pressure, in congested traffic and in a monotonous sitting position. This leads to unhealthy working conditions, especially in terms of physical and psychological stress. The aim of this study is to investigate whether an active steering system can alleviate the musculoskeletal stress involved in manoeuvring a bus. Twenty bus drivers drove a city bus equipped with the Volvo dynamic steering (VDS) support system in real traffic. Steering effort was evaluated with electromyography and with a questionnaire. Compared to baseline, VDS significantly reduced the required muscle activity by on average 15–25% while turning, and up to 68% in the part of the manoeuvre requiring maximum effort. The bus drivers believed that VDS will help reduce neck and shoulder problems, and they expressed a desire to have VDS installed in their own bus.  相似文献   
73.
We have evaluated the role of a rapid and radical method of amniodrainage in the treatment of severe twin–twin transfusion. The outcome of 15 patients with severe twin–twin transfusion for which a amniodrainage was performed by means of a vacuum bottle system was compared with the outcome of 15 patients with a similar condition, matched for gestational age at the time of the initial procedure and drained using a standard procedure. In the study group the amniodrainage ended when no amniotic fluid could be aspirated, whereas the women in the standard group were drained with a syringe system and the fluid was removed until the deepest amniotic fluid pool was <8 cm. At the initial procedure, the mean volume of amniotic fluid drained was significantly (p<0.05) higher (3252 vs 2153 ml) and the length of the procedure significantly (p<0.001) shorter (21 vs 41 min) in the study group than in the standard group. The mean post-procedure amniotic fluid index was significantly (p<0.001) smaller (2.9 vs 7.7 cm) after radical amniodrainage than after the standard amniodrainage. The mean number of procedures was significantly (p<0.001) lower (1.5 vs 5.6) in the study group compared to the standard group. In the study group the mean placental thickness increased significantly (p<0.001) from 9 mm before the procedure to 49 mm after, and the overall perinatal survival rate was 80% and the proportion of pregnancies with at least one survivor was 93%. The present data indicate that early, rapid and radical amniodrainage is an effective and low-cost therapy for severe twin–twin transfusion syndrome. Compared to the standard amniodrainage technique it also appears to reduce the need for multiple procedures. Copyright © 2001 John Wiley & Sons, Ltd.  相似文献   
74.
After extensive flooding in 2002, the European Union Solidarity Fund (EUSF) was created as an ex post loss-financing vehicle for EU member states and candidate countries in the case of disasters that exceed the government’s resources to cope. The EUSF is viewed as a valuable instrument for pooling risk among countries in Europe and potentially as a model for financing loss and damage from climate change in vulnerable countries worldwide. This paper assesses its future prospects taking account of reforms adopted in 2014. Our analysis is based on three recognized aims of the Solidarity Fund: its promotion of solidarity with those countries having the least capacity to cope with major disasters; its contribution to proactive disaster risk reduction and management (climate adaptation); and its robustness with regard to its risk of depletion (stress testing). Using a simulation approach for future disasters, we conclude that the reformed EUSF’s risk of depletion, although it is reasonably robust to more frequent disasters, could be reduced by increasing member state contributions and/or engaging in risk transfer. The European Commission has taken important steps in linking the fund to proactive risk reduction; yet, by changing its budgeting practices, the commission could be more proactive in encouraging risk management in member states. In its current form, the EUSF does not embed needs-based solidarity. Lower-income “new” member states have received disproportionately less compensation in terms of eligible losses, although on average, they have received more disaster aid than what they contribute to the fund. Solidarity could be enhanced by changing the rules for disbursing aid. After briefly describing alternative risk-pooling models in the Caribbean, Africa, and Europe, we suggest how design features of the EUSF as compared to other regional risk pools can inform discussions on the Warsaw International Loss and Damage Mechanism.  相似文献   
75.
Surface soils were collected at remote, urban and industrial sites in the Southern of Italy in order to evaluate PAH concentrations and assess the toxic effects by a battery of ecotoxicological tests. The tests were performed on whole soils and on both organic and aqueous extracts. Further goal of this study was to integrate the results coming from each test and matrix in a synthetic toxicity index. The highest summation sigmaPAH concentrations were measured at the industrial soil, although this one did not show an high ecotoxicological risk. Among the performed tests, the phytotoxicity tests showed the highest sensitivity. For whole soil, the worst case always has been represented by test through bacteria. Our results could represent the first step toward the selection of a proper battery to characterize the soil ecotoxicological risk.  相似文献   
76.
Hg2+不仅污染环境,还会引发多种疾病,危害人体健康.因此,实现对Hg2+的快速灵敏检测十分必要.传统的Hg2+检测方法存在一定的局限性,而基于T-Hg2+-T结构的汞离子生物传感器具有高特异性、高稳定性的优势,近些年得到广泛研究和应用.本文简要介绍了T-Hg2+-T结构的概念和特点,并从荧光型、比色型和电化学型3个方面综述了基于T-Hg2+-T结构的汞离子生物传感器的研究进展,对未来的发展前景进行了展望.  相似文献   
77.
Many species of marine fish are typified by large population sizes, strong migratory behavior, high fecundity, and pelagic eggs and larvae that are passively transported by ocean currents, all features that tend to increase gene flow, and hence reduce genetic partitioning, among localized populations. The plaice, Pleuronectes platessa, is a commercially important demersal species that exhibits all of these characteristics. We analyzed genetic variation at eight microsatellite loci in samples of spawning adults (N = 348) from the coasts of Ireland, Iceland, and, for the first time, from the Baltic Sea. Significant differentiation was observed between Iceland and Irish and Baltic Sea samples. However, there were no genetic differences between Irish and Baltic Sea samples, which contrast with the significant differentiation reported between Baltic Sea and North Sea/Atlantic populations of other flatfish species. To increase the data set, we carried out a cross-calibration exercise, allowing us to perform a joint analysis of data with an earlier study on adult and juvenile plaice (N = 480) collected over a broad geographic range, using six microsatellite loci in common to the two studies. Significant differentiation was observed between fish collected at the northern (Iceland, Faeroes, Norway) and southern (Bay of Biscay) parts of the species range. In contrast, the results showed little evidence of genetic structuring over much of the continental shelf of Europe. We believe that bathymetric and hydrographic barriers are the major factors shaping genetic structure, while lack of structure over much of the European continental shelf may be explained by a combination of past historical events, population structure, and dynamics of the species.  相似文献   
78.
ABSTRACT

Very important in adsorption processes is the preparation of material sorbents and from this reason, the impact of washing agent of raw sorbent was analysed. The adsorption capacity was studied in relation to the function of the equilibrium time, the amount of biosorbent and the initial metal(II) ions concentration. In this research for the sake of comparison, the sorptive properties of out-of-date coffee were compared to coffee washed with different agents (mineral acids and water). The scanning electron microscopy and Fourier transform infrared spectroscopy were used to characterise the biosorbents and to identify the functional groups that participated in metal(II) ions bonding. The obtained results clearly indicate that the out-of-date coffee are effective biosorbent for cadmium(II) and nickel(II) ions from aqueous solution. However, for metal(II) ions removal efficiency could influence sorbent preparation and nickel(II) ions were best adsorbed on coffee washed with water, but cadmium(II) ions on raw biosorbent (out-of-date coffee). The best results of sorption were achieved after the contact time of 30 and 60?min, respectively for cadmium(II) and nickel(II) ions.  相似文献   
79.
The chemical recycling of cellulosic fibres may represent a next-generation fibre–fibre recycling system for cotton textiles, though remaining challenges include how to accommodate fibre blends, dyes, wrinkle-free finishes, and other impurities from finishing. These challenges may disrupt the regeneration process steps and reduce the fibre quality. This study examines the impact on regenerated viscose fibre properties of a novel alkaline/acid bleaching sequence to strip reactive dyes and dimethyloldihydroxyethyleneureas (DMDHEU) wrinkle-free finish from cotton textiles. Potentially, such a bleaching sequence could advantageously be integrated into the viscose process, reducing the costs and environmental impact of the product. The study investigates the spinning performance and mechanical properties (e.g., tenacity and elongation) of the regenerated viscose fibres. The alkaline/acid bleaching sequence was found to strip the reactive dye and DMDHEU wrinkle-free finish from the cotton fabric, so the resulting pulp could successfully be spun into viscose fibres, though the mechanical properties of these fibres were worse than those of commercial viscose fibres. This study finds that reactive dyes and DMDHEU wrinkle-free finish affect the viscose dope quality and the regeneration performance. The results might lead to progress in overcoming quality challenges in cellulosic chemical recycling.  相似文献   
80.
It has been frequently demonstrated that mercury (Hg) concentrations in fish rise in newly constructed hydroelectric reservoirs in the Northern Hemisphere. In the present work, we studied whether similar effects take place also in a tropical upland reservoir during impoundment and discuss possible causes and implications. Total Hg concentrations in fish and several soil and water parameters were determined before and after flooding at Rio Manso hydroelectric power plant in western Brazil. The Hg concentrations in soil and sediment were within the background levels in the region (22-35 ng g(-1) dry weight). There was a strong positive correlation between Hg and carbon and sulphur in sediment. Predatory fish had total Hg concentrations ranging between 70 and 210 ng g(-1) f.w. 7 years before flooding and between 72 and 755 ng g(-1) f.w. during flooding, but increased to between 216 and 938 ng g(-1) f.w. in the piscivorous and carnivorous species Pseudoplatystoma fasciatum, cachara, and Salminus brasiliensis, dourado, 3 years after flooding. At the same time, concentrations of organic carbon in the water increased and oxygen concentrations decreased, indicating increased decomposition and anoxia as contributing to the increased Hg concentrations in fish. The present fish Hg concentrations in commonly consumed piscivorous species are a threat to the health of the population dependent on fishing in the dam and downstream river for sustenance. Mercury exposure can be reduced by following fish consumption recommendations until fish Hg concentrations decrease to a safe level.  相似文献   
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