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Scott Alan Carson 《Historical methods》2018,51(1):1-12
When traditional methods for measuring economic welfare are scarce or unreliable, heights and BMIs are now well-accepted measurements that represent biological conditions during economic development. Weight, after controlling for height, is an additional measure for current net nutrition. Little is known about how weights varied among Mexicans living in the nineteenth century American West. Between 1870 and 1920, average Mexican weight was low and remained constant. Mexican farmers had the heaviest weights, and unskilled worker weights were low. Weight of Mexican-born individuals were higher than Mexicans born in the United States at low weights but lower at high weights. For combined characteristics, weight varied the most with age, an uncontrollable characteristic, indicating that nineteenth century Mexican current net nutrition varied the most with factors over which they had no control. 相似文献
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James W. Scott 《Journal of Historical Geography》1976,2(4):387-388
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Graham W. Scott Stuart Humphries Dominic C. Henri 《Journal of Geography in Higher Education》2019,43(3):280-298
Residential field courses are important and should be designed and delivered to maximize their value to students, staff and institutions. In this context, we use a novel approach involving analysis of the daily affective and conative reflections of students immersed in the field course experience to better understand student engagement with fieldwork. We show that students base their field course choice on a range of factors (costs and benefits) and that these choices subsequently influence student expectations and motivation to engage with fieldwork. We also show that the motivation of students to engage with fieldwork-based learning varies from person to person and from day to day. Our findings suggest that having a more nuanced understanding of the decisions students make when deciding which field course to enrol upon would enhance our ability to design attractive, accessible and useful field courses; that having an awareness of the expectations of students around field courses would enable us to better prepare them to undertake them; and that students are more motivated when they are afforded an opportunity to work independently and perceive themselves to have ownership of their learning. 相似文献
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Matt A. White Alex G. Cook Scott A. Hocknull David A. Elliott 《Alcheringa: An Australasian Journal of Paleontology》2013,37(4):435-441
WHITE, M.A., FALKINGHAM, P.L., COOK, A.G., HOCKNULL, S.A. & ELLIOTT, D.A., 2013. Morphological comparisons of metacarpal I for Australovenator wintonensis and Rapator ornitholestoides: implications for their taxonomic relationships. Alcheringa 37, 1 - 7. ISSN 0311-5518.Various comparisons of left metacarpal I of the Australovenator wintonensis holotype have been made with Rapator ornitholestoides. These specimens were identified as being morphologically more similar than either was to that of the neovenatorid Megaraptor namunhuaiquii. Owing to the poor preservation of A. wintonensis and R. ornitholestoides, distinct morphological separation between the two appeared minimal. The recent discovery of a near perfectly preserved right metacarpal I of A. wintonensis enables a direct and accurate comparison with R. ornitholestoides. Distinct morphological differences exist between the metacarpals of the two species. A re-evaluation of the age of the A. wintonensis holotype site (AODL 85 ‘Matilda Site’) with zircon dating reveals a maximum age of 95 Ma, 10 Ma younger than the Griman Creek Formation at Lightning Ridge, from which R. ornitholestoides was recovered. This age difference detracts from the probability that the specimens belong to the same genus.Matt A. White? [fossilised@hotmail.com], School of Engineering, The University of Newcastle, Callaghan, New South Wales 2308, Australia; Peter L. Falkingham? [pfalkingham@rvc.ac.uk], Department of Comparative Biomedical Sciences, Structure and Motion Laboratory, Royal Veterinary College, London, UK; Alex G. Cook [alex.cook@y7mail.com] and Scott A. Hocknull [scott.hocknull@qm.qld.gov.au], Ancient environments, Queensland Museum, Hendra, Queensland, 4011, Australia; David A. Elliott [david.elliott@aaod.com.au], Australian Age of Dinosaurs Museum of Natural History, The Jump Up, Winton, Queensland, 4735, Australia. ?Also affiliated with Australian Age of Dinosaurs Museum of Natural History, The Jump Up, Winton, Queensland 4735, Australia. ?Also affiliated with Department of Ecology and Evolutionary Biology, Division of Biology and Medicine, Brown University, USA. Received 22.9.2012; revised 13.1.2013; accepted 17.1.2013. 相似文献
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