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41.
We have compared three legal and administrative systems of risk management in Sweden, namely those responsible for work environment, environmental protection and chemicals control. Large differences were found in terms of the organisational structure and the general modi operandi of government activities in the three areas. Many of these differences seem to be the result not of deliberate choice, but rather of the lack of coordination between policy areas. One of the most striking differences is the much lower priority assigned to enforcement activities in the environmental than in the occupational health sector. It is concluded that systematic comparisons of experiences from different policy areas can be helpful in improving the efficiency of risk management.  相似文献   
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Abstract: Although pollinator declines are a global biodiversity threat, the demography of the western honeybee (Apis mellifera) has not been considered by conservationists because it is biased by the activity of beekeepers. To fill this gap in pollinator decline censuses and to provide a broad picture of the current status of honeybees across their natural range, we used microsatellite genetic markers to estimate colony densities and genetic diversity at different locations in Europe, Africa, and central Asia that had different patterns of land use. Genetic diversity and colony densities were highest in South Africa and lowest in Northern Europe and were correlated with mean annual temperature. Confounding factors not related to climate, however, are also likely to influence genetic diversity and colony densities in honeybee populations. Land use showed a significantly negative influence over genetic diversity and the density of honeybee colonies over all sampling locations. In Europe honeybees sampled in nature reserves had genetic diversity and colony densities similar to those sampled in agricultural landscapes, which suggests that the former are not wild but may have come from managed hives. Other results also support this idea: putative wild bees were rare in our European samples, and the mean estimated density of honeybee colonies on the continent closely resembled the reported mean number of managed hives. Current densities of European honeybee populations are in the same range as those found in the adverse climatic conditions of the Kalahari and Saharan deserts, which suggests that beekeeping activities do not compensate for the loss of wild colonies. Our findings highlight the importance of reconsidering the conservation status of honeybees in Europe and of regarding beekeeping not only as a profitable business for producing honey, but also as an essential component of biodiversity conservation.  相似文献   
44.
Here we present the pooled analysis of 2 case–control studies on the association of brain tumours with mobile phone use. Use of analogue cellular phones increased the risk for acoustic neuroma by 5%, 95% confidence interval (CI) = 2-9% per 100 hrs of use. The risk increased for astrocytoma grade III—IV with latency period with highest estimates using >10-year time period from first use of these phone types. The risk increased per one year of use of analogue phones by 10%, 95% CI = 6-14%, digital phones by 11%, 95% CI = 6-16%, and cordless phones by 8%, 95% CI = 5-12%. For all studied phone types OR for brain tumours, mainly acoustic neuroma and malignant brain tumours, increased with latency period, especially for astrocytoma grade III—IV.  相似文献   
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描述了罗斯比中心区域气候模型(RCA2)并依据观测评估了其对整个欧洲当前气候的模拟结果.指出了模型平均气候和气候变率中的系统偏差,确定了关键参数化的缺欠.对一些近地面参数,尤其是温度、降水、地表能量收支和云量进行了较为详细的研究.模型模拟的最近的气候和变率与真实情况高度吻合.强调了地表辐射收支分量的补偿误差,这些偏差的基本原因追溯到云、降水和辐射参数化的相关方面.模型有过于频繁产生小量级降水的倾向,这直接影响到云-辐射相互作用和地表温度的模拟.在评估由分析的边界条件驱动的高分辨率RCM时,对观测结果的使用要非常小心.当考虑到降水和云量时更是如此,因为观测的不确定性经常大于RCM的偏差.  相似文献   
47.
The ongoing program Clean Air for Europe (CAFE) is an initiative from the EU Commission to establish a coordinated effort to reach better air quality in the EU. The focus is on particulate matter as it has been shown to have large impact on human health. CAFE requested that WHO make a review of the latest findings on air pollutants and health to facilitate assessments of the different air pollutants and their health effects. The WHO review project on health aspects of air pollution in Europe confirmed that exposure to particulate matter (PM), despite the lower levels we face today, still poses a significant risk to human health. Using the recommended uniform risk coefficients for health impact assessment of PM, regardless of sources, premature mortality related to long-range transported anthropogenic particles has been estimated to be about 3500 deaths per year for the Swedish population, corresponding to a reduction in life expectancy of up to about seven months. The influence of local sources is more difficult to estimate due to large uncertainties when linking available risk coefficients to exposure data, but the estimates indicate about 1800 deaths brought forward each year with a life expectancy reduction of about 2-3 months. However, some sectors of the population are exposed to quite high locally induced concentrations and are likely to suffer excessive reductions in life expectancy. Since the literature increasingly supports assumptions that combustion related particles are associated with higher relative risks, further studies may shift the focus for abatement strategies. CAFE sets out to establish a general cost effective abatement strategy for atmospheric particles. Our results, based on studies of background exposure, show that long-range transported sulfate rich particles dominate the health effects of PM in Sweden. The same results would be found for the whole of Scandinavia and many countries influenced by transboundary air pollution. However, several health studies, including epidemiological studies with a finer spatial resolution, indicate that engine exhaust particles are more damaging to health than other particles. These contradictory findings must be understood and source specific risk estimates have to be established by expert bodies, otherwise it will not be possible to find the most cost effective abatement strategy for Europe. We are not happy with today's situation where every strategy to reduce PM concentrations is estimated to have the same impact per unit change in the mass concentration. Obviously there is a striking need to introduce more specific exposure variables and a higher geographical resolution in epidemiology as well as in health impact assessments.  相似文献   
48.
Jones CG  Willén U  Ullerstig A  Hansson U 《Ambio》2004,33(4-5):199-210
The Rossby Centre Atmospheric Regional Climate Model (RCA2) is described and simulation results, for the present climate over Europe, are evaluated against available observations. Systematic biases in the models mean climate and climate variability are documented and key parameterization weaknesses identified. The quality of near-surface parameters is investigated in some detail, particularly temperature, precipitation, the surface energy budget and cloud cover. The model simulates the recent, observed climate and variability with a high degree of realism. Compensating errors in the components of the surface radiation budget are highlighted and the fundamental causes of these biases are traced to the relevant aspects of the cloud, precipitation and radiation parameterizations. The model has a tendency to precipitate too frequently at small rates, this has a direct impact on the simulation of cloud-radiation interaction and surface temperatures. Great care must be taken in the use of observations to evaluate high resolution RCMs, when they are forced by analyzed boundary conditions. This is particularly true with respect to precipitation and cloudiness, where observational uncertainty is often larger than the RCM bias.  相似文献   
49.
A series of incubation experiments were made to measure the rate of release of dissolved organic carbon (DOC) by the jellyfish Aurelia aurita (L.) (collected in 1991–1992 in Gullmarsfjorden, Sweden). Release of DOC by medusae (9.5 to 18 cm in diameter) from the Skagerrak ranged from 0.70 to 1.6 mg C ind-1 d-1 with a mean of 1.2 mg C ind-1 d-1 (SD=0.29 mg C ind-1 d-1, n=10). Based on data from the literature for two medusa populations, this can be equivalent to 2.5 and 7.1% of the carbon assimilated in one season (June to September). This was similar to the amount of carbon allocated to reproduction. Bacterial abundance was monitored to evaluate the possible stimulating effect of the DOC released. Bacterial growth was stimulated by the presence of A. aurita. The importance of A. aurita as a source of DOC on a large scale is small compared to exudate from primary producers. The volume surrounding each medusa, wherein the DOC released may be enough to sustain a bacterial production such as the one reported from the Swedish west coast, is equivalent to a sphere with a diameter of 0.5 m. Thus, considering the patchy distribution of medusae, the local influence of their DOC release could be important.  相似文献   
50.
Literature on environment and representation in politics, management, and deliberation has paid little attention on the people involved: environmental representatives. The aim of this paper is to illuminate how environmental representatives in various organizational and professional contexts understand their role as representatives, and how they are shaped by their contexts. The paper argues that it is crucial to learn about the everyday reality of individual representatives to better understand the limitations and possibilities they face. The study is based on 19 interviews with environmental representatives from five organizational and professional contexts: the state, civil society, business, science, and media in Sweden. The paper concludes that some differences in experiences, for example, in freedom and constraint, can be understood in relation to the representatives’ organizational and professional affiliation. Other experiences are common: (i) all categories stated the importance of being impartial and well read; (ii) complex layers of affiliation imply that representation requires sensitivity and adjustment between different situations; and (iii) the performative aspects of representation include the representatives’ claims-making, others’ attributions, and long-term learning of their role. The article contributes an understanding of organizational conditions and the often paradoxical, layered, multifaceted, and cautious representation these individual actors perform.  相似文献   
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