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11.
Recently, we developed a GIS-Integrated Integral Risk Index (IRI) to assess human health risks in areas with presence of environmental pollutants. Contaminants were previously ranked by applying a self-organizing map (SOM) to their characteristics of persistence, bioaccumulation, and toxicity in order to obtain the Hazard Index (HI). In the present study, the original IRI was substantially improved by allowing the entrance of probabilistic data. A neuroprobabilistic HI was developed by combining SOM and Monte Carlo analysis. In general terms, the deterministic and probabilistic HIs followed a similar pattern: polychlorinated biphenyls (PCBs) and light polycyclic aromatic hydrocarbons (PAHs) were the pollutants showing the highest and lowest values of HI, respectively. However, the bioaccumulation value of heavy metals notably increased after considering a probability density function to explain the bioaccumulation factor. To check its applicability, a case study was investigated. The probabilistic integral risk was calculated in the chemical/petrochemical industrial area of Tarragona (Catalonia, Spain), where an environmental program has been carried out since 2002. The risk change between 2002 and 2005 was evaluated on the basis of probabilistic data of the levels of various pollutants in soils. The results indicated that the risk of the chemicals under study did not follow a homogeneous tendency. However, the current levels of pollution do not mean a relevant source of health risks for the local population. Moreover, the neuroprobabilistic HI seems to be an adequate tool to be taken into account in risk assessment processes.  相似文献   
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Consumer Confidence Indexes can be sensibly used in economic and social research conducted in theoretical and methodological framework of social indicators research. They are good predictors of other attitudes, such as voting preferences. Voting preferences are determined much more strongly by expectations of changes in economic conditions than by evaluations of present situation. On the other hand, Consumer Sentiment Indexes — irrespective whether they concern future or present times — are correlated more strongly with leading than with coincident indexes of economic cycles. That proves very important role of predictions, expectations and hopes in attitude formation.  相似文献   
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The Spanish Civil War (1936—1939) interrupted the evolution and development of social pedagogy, which in Spain had reached similar levels as in other European countries. This was followed by a period when Spain was isolated from developments in social welfare and the changes that go along with the economic and social transformations of cities and give rise to community action, self-help and popular education programmes. The reinstatement of democracy and of new City Councils that are genuinely devoted to solve the problems of the population are the starting point for new social services, that is for social work and social pedagogy. Initially it was practical work that gave an answer to emerging demand, followed by theoretical analysis and efforts of conceptualisation. The professionals and later the universities lead the debate on methodology. The interest and involvement of the universities increased as the Diploma in Social Education was introduced as a new university degree.  相似文献   
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Axiomatizations of the normalized Banzhaf value and the Shapley value   总被引:1,自引:1,他引:0  
A cooperative game with transferable utilities– or simply a TU-game – describes a situation in which players can obtain certain payoffs by cooperation. A solution concept for these games is a function which assigns to every such a game a distribution of payoffs over the players in the game. Famous solution concepts for TU-games are the Shapley value and the Banzhaf value. Both solution concepts have been axiomatized in various ways. An important difference between these two solution concepts is the fact that the Shapley value always distributes the payoff that can be obtained by the `grand coalition' consisting of all players cooperating together while the Banzhaf value does not satisfy this property, i.e., the Banzhaf value is not efficient. In this paper we consider the normalized Banzhaf value which distributes the payoff that can be obtained by the `grand coalition' proportional to the Banzhaf values of the players. This value does not satisfy certain axioms underlying the Banzhaf value. In this paper we introduce some new axioms that characterize the normalized Banzhaf value. We also provide an axiomatization of the Shapley value using similar axioms. Received: 10 April 1996 / Accepted: 2 June 1997  相似文献   
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Lusofonia or lusophony is often defined as an identity shared by people in areas that were once colonised by Portugal, which in Africa include Angola, Cabo Verde, Guinea-Bissau, Mozambique and São Tomé and Príncipe. Lusofonia assumes that in these places people share something – a language, certainly, but also a history and culture rooted in the Iberian Peninsula. In some ways it is a re-articulation of Gilberto Freyre’s lusotropicalismo, the idea that Portuguese were more adaptable than other Europeans to tropical climates and cultures and created more multicultural colonial communities. Those who espouse lusofonia often have a political agenda – the strengthening of the Community of Portuguese-Speaking Countries. In this article, we argue that, like lusotropicalismo, lusofonia is a dream; it is not rooted in a historical reality. It is luso-centric in that it ignores the power and persistence of local cultures and gives undue weight to Portuguese influence. With regard to Africa, lusofonia’s agenda is elite driven and assumes the inevitability of modernity and globalisation. And we demonstrate that it was through Upper Guinean institutions and languages, and not colonial ones, that community and fellowship were most commonly fostered in the past, as they are fostered today. Those seeking the roots of lusofonia cannot, then, look to this period of Portuguese–African engagement in Upper Guinea. There Portuguese embraced “black ways.” They operated in a peculiar multicultural space in which people possessed fluid and flexible identities. Portugal did not create that space. Lusofonia has not been the foundation for cultural unity. Rather, unity has been found in localised institutions and in Crioulo. In Guinea-Bissau, lusofonia is not an indigenous movement. If it is anything, it is the stuff of elites and foreigners and is not rooted in any historical reality.  相似文献   
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Research examining impacts of teenage childbearing on economic and social outcomes have focused on completed schooling and labor force outcomes. In this paper, we examine outcomes that have remained largely unexplored, soft skills and personality. We use Add Health data to construct relevant controls for teenage mothers and explore a set of measures that proxy for what is usually deemed in economics as “non-cognitive” or “soft skill” traits. We find that teenage childbearing increases impulsivity, a trait that has been found to have negative effects on a large set of outcomes and has a negative effect on other personality traits perceived as positive, such as openness to experiences. Our results remain consistent through a set of robustness checks, and we interpret our findings to suggest that adolescence may be a sensitive period for the development of soft skills and that childbearing may interrupt this process.  相似文献   
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The objectives of this study were to describe the different modalities of physical activity programs designed for moderate to severe dementia and to identify their impact on functional independence in activities of daily living (ADL). A critical review of randomized controlled trials related to the impact of physical activity programs in moderately to severely demented persons on ADL performance and meta-analysis of the identified studies were performed. Among the 303 identified articles, five responded to the selection criteria. Four out of the five studies demonstrated limited methodological quality. In one high-quality study, physical activity programs significantly delayed deterioration of ADL performance. The program components and ADL assessment tools vary widely across studies. Although the proposed treatments have not proven their efficiency in improving the ADL status of the patients, they were able to limit the decline in ADL functioning. Future research is warranted in order to identify clinically relevant modalities for physical activity programs for people with moderate to severe dementia.  相似文献   
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