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941.
The exposure of paving workers to polycyclic aromatic hydrocarbons (PAH) during stone mastic asphalt (SMA) paving and remixing was evaluated. The effects on the workers' PAH exposure were also evaluated during the use of an industrial by-product, coal fly ash (CFA), instead of limestone as the filler in the SMA. The PAH exposure was measured by personal air sampling and by analysing the levels of urinary naphthols, phenanthrols and 1-hydroxypyrene (1-OHP) in the workers' pre- and post-shift urine samples. The respiratory PAH exposure of the paving workers (geometric mean (GM) 5.7 microg m(-3)) was about ten-fold that of the traffic controllers (GM 0.43 microg m(-3)). The levels of PAH metabolites were significantly higher (p < 0.05) in the post-shift urine samples than in the pre-shift urine samples, and the levels of metabolites in the post-shift urine of paving workers were significantly higher than in that of the controls (p < 0.01). Urinary 1-naphthol correlated well with the airborne concentrations of the two- to three-ring PAHs (r = 0.544, p = 0.003) and naphthalene (r = 0.655, p < 0.001), when non-smoking paving workers were tested. A good correlation was observed between urinary 1-OHP and the airborne concentrations of the four- to six-ring PAHs (r = 0.524, p = 0.003) as well as total PAHs (r = 0.575, p = 0.001). The concentrations of 1-OHP and phenanthrols in the urine of the pavers were significantly higher (p < 0.01) during remixing than during SMA paving. The CFA in the asphalt had no effect on the airborne PAH exposure or on the concentrations of the PAH metabolites in the paving workers' urine.  相似文献   
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Objective: Drowsy driving is a profound road safety issue. In patients with excessive daytime sleepiness (EDS), the Maintenance of Wakefulness Test (MWT) is commonly used to evaluate driving ability. However, there is little evidence that MWT predicts driving performance, and several sleep latency cutoffs have been suggested.

Methods: Based on a retrospective chart analysis of patients with an MWT and a driving ability assessment between January 2006 and November 2014, we identified 63 studies in 60 patients. The driving ability assessment judged the patients as qualified or disqualified for commercial driving. MWT latencies to 3?s of alpha activity, 3?s of drowsiness (microsleep), and sleep onset were compared between qualified and disqualified patients and their validity to identify driving qualification was evaluated.

Results: Disqualified patients had shorter alpha, microsleep, and sleep latencies, but the latency distributions were widely overlapping. MWT accuracy to predict driving performance was poor: two thirds of short sleep latencies were false positives. Adding information from alpha and microsleep latencies added little extra accuracy.

Conclusions: MWT results correlate poorly with driving performance in a 2-h test irrespective of sleep latency cutoff or added alpha/microsleep latency data. Better diagnostic tools are needed to evaluate driving performance in patients with EDS.  相似文献   
946.
Throughfall was collected in a Scots pine forest exposed to about 14 microg m(-3) of both SO2 and NO2, and in a control forest with 1 microg m(-3) SO2 and < 1 microg m(-3) NO2. Precipitation was collected in a nearby open field. Collection was performed on an event basis during the whole vegetation period. Exposure was made by an open-air release system during the vegetation period, except during rain and at night. Additional sulfate deposition in the exposed forest (compared to control forest) was nearly equal to dry deposition of sulfur dioxide, as estimated with a stomatal conductance model adapted for the particular forest. It is thus concluded that essentially all of the dry deposited sulfur dioxide is eventually extracted and appears in throughfall-including the fraction that has been deposited through stomata. Attempts to relate net throughfall deposition to dry deposition of sulfate in the control forest were inconclusive, since a minor (10%) uncertainty in the water balance had a major influence on calculated deposition velocity for particulate sulfate. Nitrate throughfall deposition is about half of the open field wet deposition, both for the exposed and control forest. Thus, a long-term exposure with about 14 microg m(-3) NO2 decreased nitrate throughfall deposition.  相似文献   
947.
The planning process for wind farm projects appears to be a complicated matter in many cases. Despite the positive attitude towards wind power in general, local wind farm projects often face strong opposition. The aim of this study is to shed more light on residents’ perceptions of participation in the planning process of wind farms. This study is based on interview data (N?=?22) and survey data (N?=?291) collected from residents living near two Finnish large-scale onshore wind farms built about 1.5 years before the data were collected. The results indicate that residents’ participation in the planning process was rather passive and the vast majority of the respondents perceived that they did not have an opportunity to participate. Quite interestingly, perceived participation in the planning process resulted in a decrease in acceptability in terms of perceived well-being. Furthermore, the results indicate that the need for participation does not expire after the planning process for a wind farm has concluded. Thus, project developers should be prepared to continue communication with residents after the planning phase.  相似文献   
948.
Concentrations of inorganic tin (Sninorg), tributyltin (TBT) and its degradation products dibutyltin (DBT) and monobutyltin (MBT) were measured in surface sediments and in two cores from the Toulon Bay, hosting the major French military harbour. Anticipating planned dredging, the aim of the present work is to map and evaluate for the first time the recent and historic contamination of these sediments by inorganic and organic Sn species derived from antifouling paints used for various naval domains including military, trade, tourism and leisure. Tin and butyl-Sn concentrations in the bay varied strongly (4 orders of magnitude), depending on the site, showing maximum values near the shipyards. The concentrations of total Sn (1.3–112 μg g?1), TBT (<0.5–2,700 ng g?1), DBT (<0.5–1,800 ng g?1) and MBT (0.5–1,000 ng g?1) generally decreased towards the open sea, i.e. as a function of both distance from the presumed main source and bottom currents. Progressive degradation state of the butyl-Sn species according to the same spatial scheme and the enrichment factors support the scenario of a strongly polluted bay with exportation of polluted sediment to the open Mediterranean. Low degradation and the historical records of butyl-Sn species in two 210Pb-dated sediment cores, representative of the Northern Bay, are consistent with the relatively recent use of TBT by military shipyards and confirm maximum pollution during the 1970s, which will persist in the anoxic sediments for several centuries. The results show that (a) degradation kinetics of butyl-Sn species depend on environmental conditions, (b) the final degradation product SninorgBT is by far the dominant species after 10–12 half-life periods and (c) using recent data to reliably assess former TBT contamination requires the use of a modified butyl-Sn degradation index BDImod. Resuspension of extremely contaminated subsurface sediments by the scheduled dredging will probably result in mobilization of important amounts of butyl-Sn species.  相似文献   
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Individuals differ consistently in their behavioural reactions towards novel objects and new situations. Reaction to novelty is one part of a suit of individually consistent behaviours called coping strategies or personalities and is often summarised as bold or shy behaviour. Coping strategies could be particularly important for migrating birds exposed to novel environments on their journeys. We compared the average approach latencies to a novel object among migrants and residents in partially migratory blue tits Cyanistes caeruleus. In this test, we found migrating blue tits to have shorter approach latencies than had resident ones. Behavioural reactions to novelty can affect the readiness to migrate and short approach latency may have an adaptive value during migration. Individual behaviour towards novelty might be incorporated among the factors associated with migratory or resident behaviour in a partially migratory population.  相似文献   
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