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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   
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The appearance of rich and diverse funerary practices is one of the hallmarks of the Late Epipalaeolithic Natufian in the Levant. Numerous burials at a number of sites excavated mostly in the Mediterranean zone of the southern Levant have fed into the interpretation of the Natufian as a sedentary society of complex hunter-gatherers. Here, we report on the human remains recovered from Shubayqa 1, a well-dated early to late Natufian site in northeast Jordan. The majority of the minimum of 23 individuals that are represented are perinates and infants, which represents an atypical population profile. Ground stone artifacts and traces of colorants are associated with some of these individuals, providing a rare insight into funerary treatment of subadults in Natufian contexts. We interpret the Shubayqa 1 evidence in the light of current and ongoing debates concerning Natufian burial practices and the issue of social complexity.  相似文献   
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The investigation of Lenin's brain by the German neurobiologist Oskar Vogt from Berlin and his Russian collaborators in Moscow is one of the most exciting and simultaneously oddest chapters in the history of medicine. With the bizarre claim to be able to detect the material substrate of genius it provoked as much unrealistic expectations in the public as strong criticism by the scientific community of brain researchers. The present paper deals in a brief survey with the history of collecting and measuring the brains of famous persons in general and particularly with the historical, political and social circumstances of the performed investigation of Lenin's brain. In this connection the epistemological and technical prereqisites of architectonical brain research and its means of the topographical representation of complex histo‐anatomical and physiological differences in the brain cortex are shortly discussed. The opening of Russian archives after the socio‐economic turn of the year 1991 brought up new background facts in Lenin's pathobiography; together with the sources from German archives a rather extensive reconstruction of the historical events between Lenin's death in 1924 and the final report of the Moscow Brain Research Institute (Institute Mozga) to the Politburo of the Russian Communist Party (Bolsheviki) in 1936 is possible now.  相似文献   
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Thermoluminescence dating of heated flint artefacts from the Middle Palaeolithic sequence of Chez-Pinaud Jonzac (France) places an assemblage of Quina type Mousterian into MIS 4, while the overlying assemblage of Denticulate Mousterian which is followed by two layers with Mousterian of Acheulean Tradition are all assigned to MIS 3. TL dating is used to verify the mixed nature of deposits from which diagnostic Middle as well as Upper Palaeolithic tools were recovered. The TL ages are significantly different for samples from this layer and broadly agree with the archaeological attributions. While the study is generally limited by the low number of heated samples available, a correlation with a generalized chronostratigraphic sequence is possible by including proxy data from the faunal remains associated with the lithic assemblages in question. The Quina Mousterian in southwestern France, therefore, can be placed by chronometric dating methods in MIS 4 to MIS 3.  相似文献   
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The OSL, post-IR OSL and pulsed post-IR OSL applied to polymineral grains and calculated by fitting to the data the contributions from fast, medium and slow components revealed that the polymineral samples under study are dominated by the medium component. An increase in D e ’s with increasing integration intervals was observed, which is considered as an indication of increasing medium and decayed fast component; and the equivalent doses obtained using different components or minerals reflect also the shape of the dose distributions. The identified fast component in polymineral sample has photoionization cross section of 1.2±0.02 × 10?17 cm2. The present study shows the usefulness of the application of different luminescence techniques combined with fitting procedures as a check which should be adopted in dating protocols. Based on luminescence ages obtained on poly-mineral grains from prehistoric pottery samples from the Boroo settlement, Mongolia, which are in agreement with independent age control by 14C on charcoal material, it is argued that the manufacturing of Xiongnu — pottery at this site lasted until ca. 130±75 AD.  相似文献   
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