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31.
Analyses of aromatic chloroethers in salmon (Salmo salar), white-tailed eagle (Hailaetus albicilla) and fish liver oil have been performed by improved clean up method which separates polychlorinated diphenyl ethers (PCDEs), anisoles and veratroles (PCAs and PCVs), phenoxy anisoles and biphenyl anisoles (PCPAs and PCBAs), dioxins and dibenzofurans (PCDDs and PCDFs) to different fractions, respectively. Compounds from all these substance groups were detected and many of them identified with authentic model compounds.  相似文献   
32.
The most abundant volatile organochlorine compounds (VOCCs), trichloroacetic and dichloroacetic acids and AOX, were determined in bleaching effluent and waste water from three kraft pulp mills during ClO2 bleaching. 0.6–7.7 g of VOCCs per ton bleached pulp were formed, the most abundant being chloroform and dichloroacetic acid methyl ester. Most of the VOCCs were removed during treatment, and it was estimated that 2–30 t of VOCCs would be removed annually from activated sludge treatment plants in Finnish kraft pulp mills using elemental chlorine free bleaching, most likely by volatilization. Dichloroacetic acid was formed in considerably higher amounts than trichloroacetic acid, and both compounds were removed effectively during treatment. The formation of all organochlorine compounds decreased considerably when non-chlorinated bleaching was employed.  相似文献   
33.
The abundance of epiphytic green algae has been observed to correlate strongly with air quality in several studies. In contrast to lichens, the abundance of green algae is difficult to measure accurately by visual observation. A new method based on photography and digital image processing was developed to estimate the chlorophyll content of algae growing on the bark of pine. Calibration data for the method was collected from polluted areas by spectrophotometric analysis of chlorophyll density.  相似文献   
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The hormonal environment during early development, such as maternally derived androgens in bird eggs, shapes the development of the offspring in ways that may have important long-term consequences for phenotype and behavior and, ultimately, fitness. We studied the long-term effects of yolk androgens on several phenotypic and physiological traits in male and female pied flycatchers (Ficedula hypoleuca) by experimentally elevating yolk androgen levels and rearing birds in common-garden environment in captivity. We found that high yolk androgen levels increased the basal metabolic rates in both females and males in adulthood. High yolk androgen levels did not affect male melanin coloration or plumage ornaments, or timing or speed of moult in either sex. No effect of androgen treatment on cell-mediated or humoral immune response was found in either sex. Covariation among the measured phenotypic traits was further not altered by androgen treatment. Our results suggest that exposure to high androgen levels can have long-lasting effects on some offspring traits, but do not seem to lead to different phenotypes. Furthermore, the role of yolk androgens affecting sexually selected male traits in our study species seems to be minor. The fitness consequences of yolk androgen-induced higher metabolic rates remain to be studied.  相似文献   
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According to the European prestandard ENV 342:1998, the thermal insulation of cold-protective clothing is measured with a thermal manikin. Systematic studies on the reproducibility of the values, measured with different types of clothing on the commonly used standing and walking manikins, have not been reported in the literature. Over 300 measurements were done in 8 different European laboratories. The reproducibility of the thermal insulation test results was good. The coefficient of variation was lower than 8%. The measured clothing should fit the manikin precisely, because poorly fitting clothing gave an error in the results. The correlation between parallel and serial insulation values was excellent and parallel values were about 20% lower than serial ones. The influence of ambient conditions was critical only in the case of air velocity. The reproducibility of thermal insulation test results in a single laboratory was good, and the variation was lower than 3%.  相似文献   
38.
Objective: The purpose of this study was to explore the relationship between annual alcohol consumption per capita/alcohol price index and the number of alcohol-related fatal motor vehicle accidents (AFMVAs). We were particularly interested in whether a tax reduction in 2004 increased the number of alcohol-related accidents.

Method: The data consisted of all fatal motor vehicle accidents (FMVAs) during the years 2000–2016 obtained from a database maintained by the Finnish Crash Data Institute (OTI). The data included all fatally injured drivers. We compared the OTI data to official statistics on annual alcohol consumption and the alcohol price index.

Results: There were 3,447 fatally injured drivers, of which 25% (n = 869) were intoxicated (blood alcohol concentration [BAC] ≥ 0.05%). After the reduction of the alcohol tax in 2004, the alcohol consumption rose 12.4% from 2003 to 2005 and AFMVAs rose 38%. There was a strong correlation (r = 0.7000, P < .018) between the recorded consumption of alcohol and the number of AFMVAs. There was a strong negative correlation between AFMVAs and the combined (retail + restaurant sales) alcohol price index (r = ?0.7863, P = .0005). A linear mixed-effects model showed that a 1-L increase in total alcohol consumption per capita per year increases AFMVAs by 10.6 and a one-unit increase in the price index decreases AFMVAs by 1.8 per year.

Conclusions: The correlation between alcohol consumption and alcohol-related crashes should be considered when making political decisions regarding alcohol price and availability. Any further liberalization of the alcohol policy would likely lead to an increase in alcohol-related fatal motor vehicle accidents. Similar consequences are likely to occur with drugs. Alcohol price policy is an effective way to improve road safety, but other measures taken to prevent FMVAs also seem to reduce the prevalence of AFMVAs.  相似文献   
39.
Urban air pollution has emerged as an acute problem in recent years because of its detrimental effects on health and living conditions. The research presented here aims at attaining a better understanding of phenomena associated with atmospheric pollution, and in particular with aerosol particles. The specific goal was to develop a form of air quality modelling which can forecast urban air quality for the next day using airborne pollutant, meteorological and timing variables.Hourly airborne pollutant and meteorological averages collected during the years 1995–1997 were analysed in order to identify air quality episodes having typical and the most probable combinations of air pollutant and meteorological variables. This modelling was done using the Self-Organising Map (SOM) algorithm, Sammon's mapping and fuzzy distance metrics. The clusters of data that were found were characterised by statistics. Several overlapping Multi-Layer Perceptron (MLP) models were then applied to the clustered data, each of which represented one pollution episode. The actual levels for individual pollutants could then be calculated using a combination of the MLP models which were appropriate in that situation.The analysis phase of the modelling gave clear and intuitive results regarding air quality in the area where the data had been collected. The resulting forecast showed that the modelling of gaseous pollutants is more reliable than that of the particles.  相似文献   
40.
The study included one station close to a pollution source (depth 59 m) and another far from polluted areas (depth 40 m). Samples were analysed for organic chlorine, bromine and sulfur compounds. Samples taken with a corer were sliced to the layers of 0-1, 1-4, 4-7 cm etc. down to the depth of 34 cm. The dating was made with two independent methods, the 210Po method and with the soot particle counting method. The analyses were made with a multiresidue method. Gas chromatography was connected to low resolution mass spectrometry (LRMS) or to high resolution mass spectrometry (HRMS). A different extraction was applied to screen the possible occurrence of polysulfides. Typical chlorophenol and chlorohydrocarbon traces from chlorobleaching of pulp were non-detectable. Also PCDDs, PCDFs, PCBs and various organochloride pesticides, fire retardant residues PBDEs, PBDDs and PBDFs and polychlorinated phenyl salicylates were not detected. Instead, methylated dibenzothiophenes Me-DBTs and Di-Me-DBTs, typical traces of oil based defoamers used in e.g. paper mills were found in the surface layers of the polluted site. Polysulfides were analyzed from layers representing years 1955-1970 from the polluted site. The structures of five congeners were according to GC/MS dimethyl trisulfide, 1,2,3,4-tetrathiepane, pentathiane, 1,2,3,4-tetrathiane and 1,2,4,5-tetrathiepane. Many of the analyzed pollutants have not been reported earlier from Lake Ladoga. The only positive observations were from oil-based defoamers used in paper mills, and from polysulfides, which are either of natural origin or indicate a discharge in the 1950s and 1960s. Owing to the large spreadout and dilution, the concentrations are low even at moderate distances from the pollution centers.  相似文献   
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