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331.
Iris Glaesslein 《L'Anthropologie》2009,113(1):198
The Microlithic industries of lower Palaeolithic central Europe have been speculated to be a result of raw material availability and therefore natural constraints. However, on some sites such as Bilzingsleben and Vertessz?ll?s, raw material constraints do not apply. Clearly here has been a positive selection for small-scale tools that must have different explanations. The seemingly stable pattern of forms unrelated to raw material properties, leads to the inference that early hominin societies possessed and transmitted over generations, a defined set of behavioural norms. The paper argues that patterns of choice can be isolated within lower Palaeolithic stone tool assemblages that are distinct from patterns of ecological restraint. 相似文献
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Naturally-occurring deuterium stable isotope ratios can potentially be used to trace water resource use by animals, but estimating the contribution of isotopically distinct water sources requires the accurate prediction of isotopic discrimination factors between water inputs and an animals body water pool. We examined the feasibility of using estimates of water fluxes between a bird and its environment with a mass-balance model for the deuterium stable isotope ratio of avian body water (Dbody) to predict isotopic discrimination factors. Apparent fractionation and thus discrimination factors were predicted to vary with the proportion of an animals total water losses than could be attributed to evaporative processes. To test our ability to predict isotopic discrimination, we manipulated water intake and evaporative water loss in rock doves (Columba livia) by providing them with fresh water or 0.15 M NaCl solution in thermoneutral or hot environments. After we switched the birds from drinking water with D=–95 VSMOW (Vienna Standard Mean Ocean Water) to enriched drinking water with D=+52 VSMOW, steady-state Dbody was approached asymptotically. The equilibrium Dbody was enriched by 10–50 relative to water inputs. After isotopic equilibrium was reached, the degree of enrichment was positively related (r2=0.34) to the fraction of total water loss that occurred by evaporation
supporting the major prediction of the model. The variation we observed in discrimination factors suggests that the apparent fractionation of deuterium will be difficult to predict accurately under natural conditions. Our results show that accurate estimates of the contribution of different water sources to a birds body water pool require large deuterium isotopic differences between the sources. 相似文献
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Marie-Yvane Daire 《L'Anthropologie》2007,111(1):106-131
The attention is turned here to one kind of tools, characterized by a special morphology: the grooved hammer-stones. They are known in Europe and all over the world in various cultures, as Neolithic or Bronze Age remains and generally linked to extraction or mining activity; but, the discovery of several of these tools in western France, within pre-roman archaeological contexts, especially in sites devoted to marine salt production, leads us to a discussion on dating and the function of such tools, and feeds a more general reflexion about the existence of a specialised lithic set of tools during the Iron Age. 相似文献
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Encarnación Rubio Magdalena Comín Gema Montón Tomás Martínez Rosa Magallón 《Revista espa?ola de geriatría y gerontología》2014
Objectives
To describe the use of health and social services, and to analyze the influence of functional capacity for Instrumental Activities of Daily Living (IADL) and other factors in their use.Method
Cross-sectional study in a non-institutionalized population older than 64 years old in a basic rural health area of Zaragoza. Dependent variables: use of different health and social services. Main independent variable: functional capacity for IADL according to the Lawton-Brody. Confounding variables: sociodemographic, physical exercise, comorbidity, self-perceived health, walking aids, social resources and economic resources (OARS-MAFQ). The relationship between the use of services and functional capacity for IADL was assessed using crude OR (ORC) and adjusted (adjusted OR) with CI95% by means of multivariate logistic regression models.Results
The use of social and health services increased with age and worse functional capacity for IADL. The increased use of health services was related with bad stage of health, limited social and economic resources, physical inactivity and female. The increased use of home help services was related with limited social resources, low education level and male. Regular physical activity and using walking aids were associated with greater participation in recreational activities.Conclusions
The probability of using social and health services increased in older people with impaired functional capacity for IADL. The specific use of them changed according to differences in health, demographic and contextual features. 相似文献340.