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National Park of Tijuca in Rio de Janeiro (Brazil) is about 3,300 ha and considered the largest urban forest in the world. Its floristic composition is typical of Atlantic Rain Forest. The reserve is being altered because of fire occurrences and urban expansion. This study identified locations and causes of forest fires, and makes management recommendations to restore damaged areas. From 1991 to 2000, forest firefighters recorded an average of 75-fire occurrences/year. Identified causes included hot air balloons (24%), intentional (24%), rubbish burning (21%) and religious practices (17%). Primary fuels included invasive grasses and ferns. Although hot air balloons destroyed larger areas of forest in each occurrence, a greater number of fires started in the invasive vegetation along roads that bisect the forest. In response to recurrent forests, invasive vegetation has spread gradually into the forest increasing forest degradation. To decrease fire damage, sites with high fire frequencies and density of invasive vegetation were planted with less flammable species. Results indicate that fire frequency decreased and density of invasive vegetation declined. This approach appears to prevent fire incidence, reduce the need for fire fighting, and preserve existing biodiversity.  相似文献   
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Management research is especially open to the benefits of using insights from a variety of social science disciplines but it should not use these indiscriminately. A strategy of pragmatic pluralism is proposed as a way of ensuring that concepts taken from different social science paradigms or disciplines are drawn together into a single coherent perspective to shape the particular study to which they relate. This is illustrated with reference to an ethnographic study of managerial work carried out by the author.  相似文献   
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From the Editors     
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Les auteurs analysent l'effet de la directive européenne relative à l'information et à la consultation des travailleurs sur les pratiques participatives en entreprise au Royaume‐Uni et en Irlande. Dans une analyse conceptuelle et empirique, qui fait appel à la théorie des jeux, ils formulent trois hypothèses explicatives, qu'ils cherchent à vérifier avec des données qualitatives recueillies auprès de seize entreprises. La démonstration permet de comprendre pourquoi la coopération, gage de gains mutuels, n'est pas la solution qui l'emporte dans les pays examinés, et elle nous en dit un peu plus sur l'effet des normes sur la gestion participative dans les économies de marché libérales.  相似文献   
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In recent years there has been increased interest in outcome‐based social policy‐making and management. The UK has been in the forefront of this movement but similar movements have been identified internationally. This interest in outcome‐based decision‐making has been given particular impetus through the ‘results’‐based movement in evaluation and performance management since the 1980s, which has increased in scope over time, slowly changing its emphasis from cost reduction and measuring outputs to measuring outcomes. This change has been widely welcomed by policymakers, practitioners and academics. However, there is evidence that the reality is often rather less than the rhetoric. Moreover, the ‘attribution problem’ of attributing changes in outcomes to specific social policies has remained a major issue. The conceptual solution of constructing ‘cause‐and‐effect’ models, imported from the policy evaluation field, has only recently become common for operationalising these models. This article outlines the evolution of interest in outcome‐based social policy‐making up to recent times and the growing realization of the importance of the attribution problem. It then outlines both how the ‘cause‐and‐effect’ policy modelling approach can partially tackle the attribution problem, but also its inherent limitations. Lastly, the article uses several case studies in current UK social policy‐making to demonstrate the potential importance of the reasoning embedded within cause‐and‐effect models but also the dangers in policy‐making which adopts this approach without understanding its conceptual basis or in fields where it is inappropriate, given the current state of our knowledge of social policy systems.  相似文献   
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The objective of meat inspection is to promote animal and public health by preventing, detecting, and controlling hazards originating from animals. With the improvements of sanitary level in pig herds, the hazards profile has shifted and the inspection procedures no longer target major foodborne pathogens (i.e., not risk based). Additionally, carcass manipulations performed when searching for macroscopic lesions can lead to cross‐contamination. We therefore developed a stochastic model to quantitatively describe cross‐contamination when consecutive carcasses are submitted to classic inspection procedures. The microbial hazard used to illustrate the model was Salmonella, the data set was obtained from Brazilian slaughterhouses, and some simplifying assumptions were made. The model predicted that due to cross‐contamination during inspection, the prevalence of contaminated carcass surfaces increased from 1.2% to 95.7%, whereas the mean contamination on contaminated surfaces decreased from 1 logCFU/cm² to ?0.87 logCFU/cm², and the standard deviations decreased from 0.65 to 0.19. These results are explained by the fact that, due to carcass manipulations with hands, knives, and hooks, including the cutting of contaminated lymph nodes, Salmonella is transferred to previously uncontaminated carcasses, but in small quantities. These small quantities can easily go undetected during sampling. Sensitivity analyses gave insight into the model performance and showed that the touching and cutting of lymph nodes during inspection can be an important source of carcass contamination. The model can serve as a tool to support discussions on the modernization of pig carcass inspection.  相似文献   
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