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461.
ABSTRACT Recent empirical work suggests that (i) incomes are converging through time, and (ii) income and pollution levels are linked. This paper weds these two literatures by examining the spatial and temporal distribution of pollution. After establishing that theoretical predictions about whether pollution will converge are critically linked to certain structural parameters, we explore pollution convergence using state‐level data on two important pollutants—nitrogen oxides and sulfur oxides—from 1929 to 1999. We find stronger evidence of converging emission rates during the federal pollution control years (1970–1999) than during the local control years (1929–1969). These results suggest that income convergence alone may not be sufficient to induce convergence of pollutant emissions.  相似文献   
462.
This study examines the ways in which children aged 11 to 15 in six adjacent neighbourhoods in a medium-sized Swedish town place themselves and others in local space. Special attention is given to how they discuss a neighbourhood stigmatized in the public discourse and how children who live in this neighbourhood react to the negative representations of the place in which they live. The study is based on group interviews and maps. The study shows that children construct representations of their own neighbourhoods as "quiet" neighbourhoods and place objects of "trouble" and "danger" somewhere else. It is argued that this is done both in relation to their personal knowledge of the neighbourhood and in relation to local and/or media representations of their own and other neighbourhoods. It is shown that the children are influenced by media representations of a stigmatized neighbourhood, but also that they are not passive reproducers of these discourses and that some of them are able to offer counter-discourses. The children living in this neighbourhood experience difficulties in defending it as the quiet place which they perceive it to be to outsiders because of the negative discourses.  相似文献   
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The soil formation in a number of pits on a neolithic excavation was compared with that in adjacent loess soils (Hapludalfs) under forest and arable and in Bavaria, Southern Germany. The differences between the soils under consideration were mainly characterized by micromorphological quantification of the illuviated fine clay. In the archaeological pits the amount of illuviated fine clay proved to be nearly twice as much as that in the undisturbed soils. The amount of illuviated coarser matrix components (fine and coarse clay and fine silt) in the neolithic pits did not differ significantly from that in the natural soils. The large amount of illuviated fine clay in the pits was ascribed to the presence of potash during the period of their formation. The formation of coarse grained illuviation cutans was related to deforestation, after which illuviation of the fine clay decreased in intensity and came to a stop.  相似文献   
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Throughout history, scurvy has been a well‐known disease which develops due to restricted resources of fresh fruit and vegetables. The condition results from an extended limited intake of vitamin C. Although skeletal lesions associated with infantile scurvy have been well described by many authors, very little literature is available on adult scurvy and the resulting skeletal lesions. The purpose of this study was to investigate the skeletal remains of a 19th century mining population from Kimberley, South Africa, for any skeletal lesions that may be indicative of adult scurvy. Scurvy was well documented as being extremely prevalent in this population. The skeletal remains of 107 individuals, presumed to have died around 1898, were studied. The majority of these individuals were males between 19 and 45 years of age. It is likely that most individuals were migrant workers at the diamond mines. All bones were visually assessed for macroscopic indications of pathological bone alterations associated with healed scurvy. Bone samples were also taken from ambiguous lesions in order to perform histological investigations. Lesions indicative of possible healed adult scurvy were observed in 16 individuals. These lesions included bilateral ossified haematomas, osteoperiostitic bone changes and periodontal disease. Histological investigation confirmed the presence of ossified haematomas on the anterior tibiae of some individuals. Hospital records and historical documents describing the incidence of scurvy in the local hospitals and the daily diet of the black mine workers supported these findings. Copyright © 2009 John Wiley & Sons, Ltd.  相似文献   
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