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As human milk is exceptionally low in strontium-calcium () ratios, but solid foods are relatively high, it should be possible to examine the pattern of dietary supplementation and the age of weaning in prehistoric groups by reference to the ratios of juvenile skeletons. The data are presented that support this rationale, along with an investigation of the Sr/Ca values of juvenile and adult skeletons from a medieval Arab graveyard. The data from these skeletons are shown to coincide with the age-curves expected in theory, suggesting that new palaeodemographic information is indeed obtainable from studies. However, until further research is conducted, the technique provides a functional estimate of weaning patterns that is only suitable for comparative purposes. Additional research should clarify the relationship of functional to actual estimates of dietary supplementation and weaning. 相似文献
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ABSTRACTChildren’s school transport has become a major research focus over the past 20 years, particularly within the fields of planning, transport geography, and children’s geographies. However, this work has rarely considered children living with disability. This article presents the pilot component of a visual ethnographic study about school transport within families living with childhood disability. It explains why we piloted the study, details the pilot process, and presents lessons learned from piloting the study with two families of children living with different mobility needs. The lessons largely concern the design of interview guides and the interviewing process, as well as the development of an adaptive photo kit to enable children’s independent participation. The article shows how piloting qualitative studies, particularly those involving disabled children, can be invaluable in terms of improving data collection technologies and logistics, as well as enabling inclusive participation. 相似文献
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Andrew W. Nutting 《Journal of regional science》2023,63(2):290-339
Geographic inequality and racial disharmony are considered major factors in America's political divergence. This paper calculates geographic earnings inequality from 1960 to 2016 separately by race. From 2000 to 2016, White geographic inequality was significantly higher, and Hispanic geographic inequality was significantly lower, than Black and Asian geographic inequality. White geographic inequality rose from 1980 to 2008. Black and Hispanic geographic inequality fell from 1960 to 1980. Rural controls explain substantial shares of White geographic inequality in all years. Region and rural controls account for large shares of Black geographic inequality, especially from 1960 to 1990. Post-1990, geographic inequality changes are largely explained by changes in overall earnings inequality, but 1960–1990 changes are not. Between-race differences in geographic inequality translate into high-income metropolitan statistical areas having had, since 1980, significantly smaller shares of Whites among their low-income residents. 相似文献