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61.
During the last decades of the previous century, school desks with a tilt top have disappeared. The chairs have been designed for sitting upright, with the hip, knees and ankles all at right angles. However, the erect posture cannot be maintained for more than one or two minutes, after which it will result in fatigue, discomfort or poor posture. The main aim of project is to identify the type of furniture that most effectively contribute to adequate neck and back postures of the school children, by carrying out a postural analysis of a sample of school pupils when using three different types of furniture. The postures adopted by school pupils were monitored by video during several activities, such as reading, writing and painting tasks, copying from a blackboard and listening the teacher. Additionally, the characteristics of the adopted postures were assessed by registering the head tilt, flexion of the neck, trunk and hips position. All these aspects were classified and the results were recorded for future analysis. The obtained results seem to point out that the use of a school desk with a tilted table surface resulted in a reduction in trunk and neck flexion, preserving the natural lordosis in the lumbar and cervical regions. Accordingly, it can be concluded that there are alternatives to consider in the furniture design in order to eliminate tensions and, consequently, to improve children's wellbeing.  相似文献   
62.
Costa S  Arezes P 《Work (Reading, Mass.)》2012,41(Z1):2971-2973
The international standard ISO 9612:2009, regarding the determination of occupational noise exposure through an engineering method, establishes a methodology for evaluating the exposure of workers to occupational noise, through the specification of three different strategies, namely: task-based measurement (TBM); job-based measurement (JBM) and; full day measurement (FDM). In this work, questions are raised, "resulting in a literature review regarding the need to test the functionality of the three strategies, through the systematic comparison between them and analysis of their application impact at several levels. There is a need to test the compare these three strategies, since there are no peer-review studies in this domain. In fact, there are still no studies that systematically do the comparison between them and analyze the impact of their application at various levels, such as the precision and accuracy of the results, the required equipment, time spent and, most important, the estimation of the uncertainty associated to the measurements.  相似文献   
63.
Despite the interest of the social sciences in issues of exclusion and inequality, the question of disability, as a key issue of reflection, remains absent from many academic areas. The emergence of disability studies owes much to contexts in which the activism of disabled people has revealed the structural conditions that oppress and neglect experiences of disability. Bearing in mind the specific features of the Portuguese socio-political environment, two lines of inquiry are developed in this text. Firstly, what are the challenges faced by Portuguese academics in making disability a central issue, enabling it to confront the silencing of the voices and experiences of disabled people in society? Secondly, how important is it for research to engage with an ethical and political paradigm that supports the rights of disabled people?  相似文献   
64.
The scarcity of green areas in urban landscapes hinders connectivity among sites reducing the flux of organisms and seed dispersal. Ramphastos toco is an effective plant disperser in tropical landscapes, playing an important role in conserving plant connectivity. In this study we combined two methods of landscape connectivity analysis, in a way not yet explored, to assess the potential contribution of Ramphastos toco to enhancing connectivity among urban vegetation patches. We used spatial modeling techniques to evaluate least cost routes, or those that facilitate bird movement through green urban areas, in Belo Horizonte, a city in Southeast Brazil. We also assessed the relative importance of forest patches for conserving both bird and seed dispersal fluxes using the integral index of connectivity. The resulting least cost route of greater accessibility for the species included in its course an important forest patch under environmental licensing for the construction of a residential condominium. The number of green urban areas covered by forest, of highest habitat quality for the species, summed to 155 patches. Of this total only 5.2% were relevant for regional connectivity, while the four most important patches are targeted by the city’s expansion plans. Ramphastos toco is an effective connector for tropical green urban areas given its adaptability, wide range of movement and seed dispersal effectiveness. We emphasize the need for incorporating ecological knowledge and the prioritization of green areas into city planning, since current expansion projects jeopardize forest patches that are crucial to the functional connectivity of the urban landscape.  相似文献   
65.
Uncontrolled urban growth has been an increasing concern in many regions throughout the world. Generated by a natural tendency of population growth in relation to unsustainable land use, city sprawl has led to complex spatial developments that are creating both benefits to, and challenges for decision makers. A major problem inherent in the uncontrolled growth of cities is the threat to the fragile cultural and ecological heritage, which may escalate to permanent and irreversible damage as a result of factors such as environmental depletion and landscape decay. Using modern geosciences and spatial information technologies as predictive tools to analyse and forecast urban growth, a regional spatial decision system may be useful in order to provide seemly and timely information on the risk of overburdening the carrying capacity regarding the historico-cultural heritage at local and regional levels.The present paper develops a predictive toolkit for urban heritage in relation to urban cultural endangerment. This common problem is shared through many regions of the world and is increasingly jeopardizing fragile archaeological landscape due to urban pressure. In this sense, and to forecast an example of this common pressure, the Algarve is exemplified as a laboratory for testing this novel methodology, relying on a combined analysis of urban growth potential and threats to the abundant presence of archaeological heritage in the area. Our appro ach supports the paradigm of city growth in the context of a common agenda emerging from the Valetta Treaty, in which preserving the archaeological heritage is recognized as a key element for sustainable development. The study provides novel empirical results from the above mentioned modelling approach, with important lessons for the developing world. This paper proposes as such, an integrative spatial analysis methodology on the issue of historico-cultural endangerment, which is a new approach to comparative spatial analysis for decision making on urban heritage endangerment at the regional scale. Later, the discussion extends to a more conceptual level of urban planning by considering the questions: Is urban sprawl influencing the way we perceive cities? If so, are there positive advantages in the paradigm of urban growth and urban sprawl which might help us to protect past heritage while ensuring sustainable and modern cities?  相似文献   
66.
This paper investigates the long‐term effects of conditional cash transfers on school attainment and child labor. To this end, we construct a dynamic heterogeneous agent model, calibrate it with Brazilian data, and introduce a policy similar to the Brazilian Bolsa Família. Our results suggest that this type of policy has a very strong impact on educational outcomes, sharply increasing primary school completion. The conditional transfer is also able to reduce the share of working children from 22% to 17%. We then compute the transition to the new steady state and show that the program actually increases child labor over the short run, because the transfer is not enough to completely cover the schooling costs, so children have to work to be able to comply with the program's schooling eligibility requirement. We also evaluate the impacts on poverty, inequality, and welfare. (JEL O11, I25, J24)  相似文献   
67.
Over the past two decades, Howard Becker's Art Worlds and Pierre Bourdieu's The Rules of Art were guidelines for the dominant paradigms in sociology of art. Nevertheless, according to Bourdieu, sociology and art do not make a good match. To overcome this dilemma, the French sociologist Nathalie Heinich proposed a “sociology from art,” based on the uniqueness of artists and their works, but she neglected artworks as sociological subject. A realistic and persistent criticism against sociology from the arts claims that artworks are fictions created by artists, therefore epistemologically unacceptable as social realities. Is it possible the making of sociology from artworks? Through theoretical review and using the example of literature, I will argue in this paper that artworks are important heuristic resources and a legitimate subject of sociological research.  相似文献   
68.
现在,很多人已经认识到,管理者和领导者并非等同关系。早在1992年,埃德加·沙因(Edgar Schein)就曾说过,领导者“创建、变革文化,管理者弘扬文化”。但是,公司从创建、成长到最终发展为成功的全球化企业,既离不开管理能力,也离不开领导能力。因此,管理和领导是两种不同的才能,尽管我们可能或多或少地具备某些先天的智力潜能,但这两种才能必须经过后天的培养与发展。换言之,领导、管理和创业能力并非什么天赋异禀,而是后天学习的结果。  相似文献   
69.
This paper studies the estimation of dynamic discrete games of incomplete information. Two main econometric issues appear in the estimation of these models: the indeterminacy problem associated with the existence of multiple equilibria and the computational burden in the solution of the game. We propose a class of pseudo maximum likelihood (PML) estimators that deals with these problems, and we study the asymptotic and finite sample properties of several estimators in this class. We first focus on two‐step PML estimators, which, although they are attractive for their computational simplicity, have some important limitations: they are seriously biased in small samples; they require consistent nonparametric estimators of players' choice probabilities in the first step, which are not always available; and they are asymptotically inefficient. Second, we show that a recursive extension of the two‐step PML, which we call nested pseudo likelihood (NPL), addresses those drawbacks at a relatively small additional computational cost. The NPL estimator is particularly useful in applications where consistent nonparametric estimates of choice probabilities either are not available or are very imprecise, e.g., models with permanent unobserved heterogeneity. Finally, we illustrate these methods in Monte Carlo experiments and in an empirical application to a model of firm entry and exit in oligopoly markets using Chilean data from several retail industries.  相似文献   
70.
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