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551.
Human serum and plasma from Sweden (n=17), the United Kingdom (the UK) (n=13) and Australia (n=40) were analyzed by high performance liquid chromatography coupled to mass spectrometry. The objective was to identify different perfluorooctane sulfonate (PFOS) isomers. Similar isomer patterns typical for the electrochemical fluorination (ECF) process were found for all samples. The linear PFOS (L-PFOS) was the major isomer found (58-70%) followed by the monosubstituted PFOS isomers 1/6-CF(3)-PFOS (18-22%) and 3/4/5-CF(3)-PFOS (13-18%). Disubstituted isomers were also detected. The percentage of L-PFOS found in the serum and plasma samples was lower compared to a standard PFOS product (76-79%). The pattern of PFOS isomers in human serum and plasma may be suggestive concerning potential isomeric discrimination since PFOS is only produced by ECF. Possibilities for such isomer discrimination are discussed. Significant higher content of L-PFOS (68%) in Swedish samples compared to Australia and the UK (59%) was also found, which may suggest differences in exposure sources for humans.  相似文献   
552.
The notion of ecosystem services is considered useful for integrating perceptions and values into decision-making on environment and nature. Sociocultural factors have been suggested to explain perceptions and values assigned to ecosystem services. We examine this by undertaking a sociocultural valuation of ecosystem services provided by the natural park of Sant Llorenç del Munt, located at the edge of the Barcelona Metropolitan Region. Four methods are used, namely a review of the literature on ecosystem services, non-participant observation, semi-structured interviews with stakeholders and a valuation survey among visitors. We assess whether visitors and other stakeholders understand the term ecosystem service, finding that the concept is rather unknown or misunderstood. Among the 28 ecosystem services identified, habitat and cultural services were the most valued. We statistically identify socioeconomic characteristics of visitors that have a main influence on their valuation of ecosystem services. We further assess diverging preferences of all stakeholders that might give rise to conflicting views about policies for protected areas. We draw lessons about the usefulness of the multi-method approach and about the management of protected areas.  相似文献   
553.
Radium isotopes are widely used in marine studies (eg. to trace water masses, to quantify mixing processes or to study submarine groundwater discharge). While 228Ra and 226Ra are usually measured using gamma spectrometry, short-lived Ra isotopes (224Ra and 223Ra) are usually measured using a Radium Delayed Coincidence Counter (RaDeCC). Here we show that the four radium isotopes can be analyzed using gamma spectrometry. We report 226Ra, 228Ra, 224Ra, 223Ra activities measured using low-background gamma spectrometry in standard samples, in water samples collected in the vicinity of our laboratory (La Palme and Vaccarès lagoons, France) but also in seawater samples collected in the plume of the Amazon river, off French Guyana (AMANDES project). The 223Ra and 224Ra activities determined in these samples using gamma spectrometry were compared to the activities determined using RaDeCC. Activities determined using the two techniques are in good agreement. Uncertainties associated with the 224Ra activities are similar for the two techniques. RaDeCC is more sensitive for the detection of low 223Ra activities. Gamma spectrometry thus constitutes an alternate method for the determination of short-lived Ra isotopes.  相似文献   
554.
A key issue in implementing adaptation strategies at the landscape level is that landowners take measures on their land collectively. We explored the role of information in collective decision-making in a landscape planning process in the Baakse Beek region, the Netherlands. Information was provided on (a) the degree to which measures contribute to multiple purposes, (b) whether they are beneficial to stakeholders representing different sectors of land use, and (c) the need for landscape-level implementation of adaptation measures. Our analysis suggests that the negotiation process resulted in collective decisions for more collaborative adaptation measures than could be expected from individual preferences previous to the planning session. Based on the results, it is plausible that the provided information enhanced integrative agreements by leading stakeholders to realize that they were mutually interdependent, both in acquiring individual benefits as well as in implementing the measures at the landscape level. Our findings are significant in the context of the emerging insight that targeted information provision for climate adaptation of landscapes can support collaboration between the relevant stakeholders.  相似文献   
555.
BACKGROUND: Mold growth is believed to be one causative factor underlying the association between dampness in buildings and increased respiratory morbidity. Measurements of beta(1-->3)-glucans and fungal extracellular polysaccharides (EPS) are used as markers of mold exposure in field studies. Little is known about their levels and determinants in homes. OBJECTIVE: To study levels and determinants of beta(1-->3)-glucan and EPS levels in mattress and living room floor dust in three European countries. METHODS: Mattress and living room floor dust was collected in the homes of 1065 German, Dutch, and Swedish (pre-)school children. All samples were analyzed for beta(1-->3)-glucans and EPS in one central laboratory. Determinants were assessed by questionnaire. RESULTS: Amounts of dust, EPS and beta(1-->3)-glucan levels differed between countries. Amounts of dust, beta(1-->3)-glucan and EPS levels for mattresses were only weakly correlated with those for living room floors. Floor dust beta(1-->3)-glucan loads, EPS loads and EPS concentrations were strongly correlated with the amount of dust sampled, which is largely determined by the type of floor that was sampled (carpeted floors had 5-20 higher amounts of dust). None of the other determinants was consistently and statistically significantly associated with amounts of dust, beta(1-->3)-glucan and EPS concentrations on floors and mattresses. CONCLUSION: Mattress dust and floor dust are two different measures of exposure to the investigated mold components. Living room floor beta(1-->3)-glucan and EPS loads and EPS concentrations are largely determined by the type of floor sampled. Differences between countries can only partly be explained by the determinants studied.  相似文献   
556.
A total of 27 per- and polyfluorinated compounds (PFCs) were determined in both house dust (n = 10) and indoor air (n = 10) from selected homes in Catalonia, Spain. Concentrations were found to be similar or lower than those previously reported for household microenvironments in other countries. Ten PFCs were detected in all house dust samples. The highest mean concentrations corresponded to perfluorodecanoic acid (PFDA) and perfluorononanoic acid (PFNA), 10.7 ng/g (median: 1.5 ng/g) and 10.4 ng/g (median: 5.4 ng/g), respectively, while the 8:2 fluorotelomer alcohol (FTOH) was the dominating neutral PFC at a concentration of 0.41 ng/g (median: 0.35 ng/g). The indoor air was dominated by the FTOHs, especially the 8:2 FTOH at a mean (median) concentration of 51 pg/m3 (median: 42 pg/m3). A limited number of ionic PFCs were also detected in the indoor air samples. Daily intakes of PFCs were estimated for average and worst case scenarios of human exposure from indoor sources. For toddlers, this resulted in average intakes of ∑ ionic PFCs of 4.9 ng/day (0.33 ng/kgbw/day for a 15 kg toddlers) and ∑ neutral PFCs of 0.072 ng/day (0.005 ng/kgbw/day) from house dust. For adults, the average daily intakes of dust were 3.6 and 0.053 ng/day (0.05 and 0.001 ng/kgbw/day for a 70 kg adult) for ∑ ionic and ∑ neutral PFCs, respectively. The average daily inhalation of ∑ neutral PFCs was estimated to be 0.9 and 1.3 ng/day (0.06 and 0.02 ng/kgbw/day) for toddlers and adults, respectively. For PFOS, the main ionic PFC detected in indoor air samples, the median intakes (based on those samples where PFOS was detected), resulted in indoor exposures of 0.06 and 0.11 ng/day (0.004 and 0.002 ng/kgbw/day) for toddlers and adults, respectively. Based on previous studies on dietary intake and drinking water consumption, both house dust and indoor air contribute significantly less to PFC exposure within this population.  相似文献   
557.
An apparent cancer cluster at a police detachment in a coastal British Columbia community was investigated. Police personnel suspected that the detachment building may have been a factor. Police personnel (20 current and 154 previous employees) associated with the detachment since 1963, the date of occupancy, were traced. After all 174 cases were contacted directly, or next of kin in case of death, a total of 16 cases of cancer or suspected cancers were reported. Of these 16, eight cases of cancer were confirmed through a cancer registry. Cancers included testicular, cervical, colon, skin (including melanoma), leukemias and lymphomas with an age range of diagnosis between 22 and 44 years. There was no evidence for an underlying event, factor or condition in the police building that could be attributed to the observed cancer cases. A possible association between these cancers and the use of police traffic radar is discussed.  相似文献   
558.
A simplistic aggregate model of global economic activity supports a 50-year visioning exercise with targets defined in terms of aggregate measures of global equity (convergence) and sustainability (contraction). Some ambitious combinations of these targets turn out to be infeasible even under the most favorable modeling assumptions. No contraction target (no reduction in fossil fuel consumption relative to the present) was possible, for example, if international capital transfers pushed per capita incomes in low-income countries above 33% of levels achieved in high-income countries. Lower prices for renewable alternatives to exhaustible resources generally made sustainability targets easier to achieve, but lower prices for renewable resources also made equity targets more difficult to achieve. Improved substitution between capital and labor made equity targets easier to achieve in relative terms, but improved substitution between capital and labor could make any given sustainability target more or less difficult to achieve. All the results suggest that it is possible to overstate the purported conflict between achieving sustainability and equity targets. The very transfers of international capital that would promote relative equity between high-income and low-income countries could also work to spread the incidence of achieving any sustainability target more evenly across their boundaries.Readers should send their comments on this paper to: BhaskarNath@aol.com within 3 months of publication of this issue.  相似文献   
559.
Climate change-related risks encompass an intensification of extreme weather events, such as fluvial and pluvial flooding, droughts, storms, and heat stress. A transparent and comprehensive division of responsibilities is a necessary—but not the only—precondition for being prepared for climate change. In this paper, we present, and preliminarily test, a method for the ex-ante assessment of the division of public and private responsibilities for climate adaptation in terms of comprehensiveness, transparency, legitimacy, and effectiveness. This method proofs particularly suited for the assessment of adaptation responsibilities in combination with a sectoral approach. It helps identifying a number of shortcomings in divisions of responsibilities for climate adaptation. We conclude that this method is useful as a diagnostic tool for identifying the expected climate change preparedness level, and recommend to combine this with ex-post analyses of real-life cases of extreme events in order to assess the actual preparedness for climate change. Besides the scientific purpose of providing a generally applicable assessment method, with this method, we also intend to assist policy-makers in developing and implementing adaptation plans at various levels.  相似文献   
560.
This paper summarizes some personal impressions of the 7th conference of the International Complex Systems Society, co-organized with “Future Earth”, held in Stockholm on August 24–26, 2017. The main point is that it is urgent and important to consider the sustainability conundrum as long-term, society-driven one, and to place societal dynamics at the core of how we, as a global society, came to this point, how ongoing dynamics are driving us towards a tipping point, and which role the Information and Communication Technology revolution plays in that process. A much wider involvement of the social sciences is essential. This also requires major changes in our thinking about sustainability—we need to develop an approach in which change is the natural state of affairs and societies attempt to impose stability on the dynamics involved. We need to focus on learning from the past, about the present, but above all for the future. And we need to shift from an entity-focused approach to a relational one, which pays more attention to contexts and networks. Other issues raised by such a shift in our thinking are about the role of science, the adoption of complex systems approaches and a few others that the paper points to.  相似文献   
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