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81.
This paper has two aims: to explore approaches to the measurement of children's daily travel to school in a context of limited geospatial data availability and to provide data regarding school choice and distance travelled to school in Soweto-Johannesburg, South Africa. The paper makes use of data from the Birth to Twenty cohort study (n?=?1428) to explore three different approaches to estimating school choice and travel to school. First, straight-line distance between home and school is calculated. Second, census geography is used to determine whether a child's home and school fall in the same area. Third, distance data are used to determine whether a child attends the nearest school. Each of these approaches highlights a different aspect of mobility, and all provide valuable data. Overall, primary-school-aged children in Soweto-Johannesburg are shown to be travelling substantial distances to school on a daily basis. Over a third travel more than 3 km one way to school, 60% attend schools outside of the suburb in which they live, and only 18% attend their nearest school. These data provide evidence for high levels of school choice in Johannesburg-Soweto, and that families and children are making substantial investments in pursuit of high-quality educational opportunities. Additionally, these data suggest that two patterns of school choice are evident: one pattern involving travel of substantial distances and requiring a higher level of financial investment and a second pattern involving choice between more local schools, requiring less travel and a more limited financial investment.  相似文献   
82.
This paper considers the “share‐altering” technical change hypothesis in a spatial general equilibrium model where individuals have different levels of skills. Building on a simple Cobb‐Douglas production function, our model shows that the implementation of skill‐biased technologies requires a sufficient proportion of highly educated individuals. Moreover, when technical progress disproportionately replaces middle‐skill jobs, the local distribution of skills will exhibit “fat‐tails,” where the proportion of both highly skilled and low‐skilled workers increases. These and several other predictions of the model are consistent with recent existing evidence, and avoid some major criticism against the “canonical” CES framework.  相似文献   
83.
This paper continues the characterization of the lead isotopic fingerprint of ancient copper mines in the north‐west of Spain. In this work, the lead isotopic compositions found in copper ores from the La Profunda mine are presented. Azurites and malachites sampled from this deposit were subjected to lead isotope analysis by multicollector ICP–MS. The results showed a clear radiogenic lead signature compatible with the presence of uranium‐rich minerals (such as zeunerite) in the same mining complex. Moreover, a rare copper artefact, found in the galleries of the mine during its modern exploitation, was also analysed and showed that local mineral was used for its manufacturing.  相似文献   
84.
This article presents a method to identify “Absolute and Relative Employment Concentration (AREC) areas” for a particular industry. Two novel characteristics of the method are that it simultaneously analyses AREC, and that it combines spatial concentration per area with the spatial concentration in neighbouring areas. The method is easy to understand and apply. It is developed to assist regional policy makers and corporate decision-makers with their investment decisions related to new infrastructure or plants. The identification of concentration areas also allows for analysing the performance of these areas in relation to characteristics such as infrastructure availability and the housing and labour market. This can yield new academic insights that are relevant for regional planners. An application of the newly developed method to five industries in a Dutch province subdivided into 502 areas illustrates the value of the method in comparison to other methods.  相似文献   
85.
This article presents the results of the excavation of a residence dated between the second and fourth centuries AD, constructed over the ruins of the South Arabian town of Makaynūn, in central Hadramawt (Yemen). The building yielded a large quantity of material including objects proving contacts between the central Hadramawt and regions located to the north‐east, such as central Oman, the Gulf area and India.  相似文献   
86.
In a talk given at Zurich in the late 1940s, Hermann Weyl discussed Ferdinand Gonseth's dialectical epistemology and considered it as being restricted too strictly to aspects of historical change. His experiences with post-Kantian dialectical philosophy, in particular Johann Gottlieb Fichte's derivation of the concept of space and matter, had been a stronger dialectical background for his own 1918 studies in purely infinitesimal geometry and the early geometrically unified field theory of matter (extending the Mie-Hilbert program). Although now Weyl distantiated himself from the speculative features of his youthful philosophizing and in particular from his earlier enthusiasm for Fichte, he again had deep doubts as to the cultural foundations of modern mathematical sciences and its role in material culture of high modernity. For Weyl, philosophical «reflection» was a cultural necessity he now turned towards Karl Jaspers' and Martin Heidegger's existentialism to find deeper grounds, similar to his turn towards Fichte's philosophy after World War I. The discussion in the late 1940s can be read as a kind of post-World-War-II «Nachtrag» to Weyl's more widely known philosophical comments on mathematics and the natural sciences published in the middle of the 1920s.  相似文献   
87.
This article examines the relationship between the introductionof women Justices of the Peace (JPs) in 1919 and the gendereddevelopment of juvenile courts in England, c. 1910–39.It argues that the campaigns for the appointment of women asJPs and for new methods of dealing with delinquent childrenwere closely connected from 1910 onwards, when the proposalwas first made that ‘suitable’ persons should beappointed to hear ‘suitable’ cases in magistratescourts. Using evidence drawn from government records and othersources, the article examines the interaction of the two campaignsand of feminist and penal reform groups in securing the remodellingof London's juvenile justice system in the Juvenile Courts (Metropolis)Act of 1920. It argues that these arrangements, and similarones adopted elsewhere in England, consciously reflected presumedfamilial and gender roles. It concludes that the replicationof the ‘traditional’ family in the composition ofthe court may have limited the ability of the youth justicesystem to be innovative in its approach to juvenile delinquencyin the period up to 1939. * a.f.logan{at}kent.ac.uk  相似文献   
88.
Globalization and neoliberalism are having significant impacts upon the cleaning industry, as in the drive for greater work “efficiency”. One way in which cleaning companies have sought to increase efficiency is through the introduction of new equipment and forms of work organization. However, such moves appear to be having negative impacts upon cleaners’ bodies, and many report significant work‐related health problems. In light of this, here we explore the bodily consequences of two possible strategies for giving cleaners a healthier workday—increasing variation within cleaners’ current work tasks or allowing them to engage in a broader range of tasks through job enlargement. Drawing upon a literature review performed as part of a recent European Union project concerning the degree of physical strain to which cleaners are exposed during cleaning, a Danish laboratory study focusing on the loads to which cleaners’ shoulder muscles, backs, and hearts were exposed by different cleaning tasks, and a field study investigating the effects of job enlargement in Danish hospitals, we show that cleaning work is characterized by repetitive work for the muscles of the body's upper extremities and by high levels of dynamic and static force upon these muscles, regardless of which modes of cleaning (old or new style of cleaning tools) are used. Equally, monitoring of heart rates and assessment of the psychosocial environment suggest that simply interchanging current cleaning tasks does not provide sufficient variation in cleaners’ work to prevent work‐related musculoskeletal or cardiovascular damage, nor to create a less mentally stressful work environment. Although introducing greater work variation through job enlargement (such as combining cleaning with kitchen and portering tasks) is often presented as an effective way to minimize musculoskeletal and cardiovascular damage, our field study shows that even this does not provide sufficient variation in physical work conditions, although improvement in some cleaners’ mental health was noted. Therefore, we conclude, prevention of musculoskeletal and cardiovascular disorders demands a much more comprehensive strategy of work redesign than that proposed by some employers and government agencies. Whether this is likely, given competitive pressures towards increased outsourcing and privatization, is, of course, the question.  相似文献   
89.
90.
Nadung’a 4 is one of the single carcass pachyderm sites recorded in East Africa during the Lower and Early Middle Pleistocene. The site has yielded an abundant lithic assemblage in close association with the partial carcass of an elephant. Conjoined pedological, geoarchaeological, spatial, technological, and taphonomical analyses have been carried out to address the relationship between hominids and elephant. The resulting data are consistent with a non-fortuitous association between both categories of remains. The lithic artefacts do not match a classical Acheulean tool-kit, as would be expected for the time period ascribed to the site, and the functional patterns inferred from their analysis make this site radically different from other purported butchery sites. The implications of these original features are discussed.  相似文献   
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