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141.
Ancient mortars from northern Italy, dating from the fifth to the seventeenth century AD, were examined in order to formulate an hypothesis regarding the origin of the white lumps often observed in these mortars and in other samples of the same geographical provenance. Various characterization techniques were employed, including scanning electron microscopy, X-ray powder diffraction and Fourier transform infrared (FTIR) and micro-FTIR spectroscopy.  相似文献   
142.
Farmer adaptation to climatic variability is explored via an analysis of corn hybrid selection in southern Ontario. Corn hybrid varieties are available for a wide range of conditions, including accumulated heat, measured as Corn Heat Units (chus). Hybrids with higher chu ratings generally have higher yields, so long as there is sufficient heat for them to mature. Farmers choose their hybrid varieties prior to the growing season, in the face of uncertainty about the chus that will accumulate at their location. Farmers in the sample counties showed a consistent tendency to adjust their hybrid selection on the basis of the previous year's growing conditions. After the high chu year of 1991, farmers chose significantly more longer-maturing and potentially higher-yielding, but riskier varieties. After the lower chu years of 1992 and 1993, farmers' hybrid selections became markedly more conservative. L'étude de I'adaptation des fermiers aux changements climatiques se fait par une analyse de /'hybridation du maïs au sud de l'Ontario. Les variétés de maïs hybrides conviennent à différentes conditions climatiques in-cluant la chaleur accumulée, mesurée en Unitées de Chaleur de Maïs (ucms). Les hybrides ayant une valeur ucm plus élevée donnent généralement un rendement plus élevéà condition qu'ils bénéficient d'assez de chaleur pour mûrir. Les fermiers des comtés sélectionnés ont démontré une tendance persistante à baser leurs sélections d'hybrides en fonction des conditions de crois-sance de I'année précédente. Depuis 1991, année ayant connu un taux élevé d'UCM, les fermiers ont opté pour un type d'hybride à croissance prolongée, au potentiel de rendement plus élevé mats également plus risqué. Les années 1992 et 1993 ayant connu un niveau ucm moins élevé, les fermiers ont alors sélectionné des hybrides plus traditionnels.  相似文献   
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Events that have become popularly known as ‘the Hindmarsh affair’ arose from conflict over a bridge development, and refer to an Aboriginal heritage issue that has had a significant impact on Australian society. 1 1 Justice Mathews (Commonwealth of Australia, 1996:1) begins her Commonwealth Hindmarsh Island Report with a similar assessment, noting how painful and divisive an affair it has been, and how enduring its legacies are likely to be.
The attendant controversy and dissension have ramified widely, beyond matters of Aboriginal heritage and its relationship to development, to include the status and role of anthropological research and reporting, past and present. A brief chronology of developments both prior to and following the Hindmarsh Island Bridge Royal Commission (1995) is provided here as a backdrop for discussion of these matters. Other salient issues also examined include: the nature of culture in relation to the complexities of ‘tradition’ and the effects of change; the structural correlates of secrets; the politics of interpretation; and the legitimacy of innovative processes in Aboriginal cultural construction and representation. In conclusion, some implications of the Hindmarsh affair for the anthropology profession are considered.  相似文献   
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This paper summarizes results of a research project funded by the Overseas Development Administration of the UK Government. Its aims were to explore the nature and extent of foreign direct investment in Poland, and to assess the extent of integration of such investment with the indigenous economy. The research involved interviews with Polish government ministries, banks, development agencies, inward investors and indigenous firms. It concludes that there are numerous financial and technical obstacles to indigenous business development. The majority of inward investors aim to serve the Polish and other Central and Eastern European markets rather than simply selling cheaply produced products to the West. Moreover, most have already developed significant local sourcing from Polish suppliers.  相似文献   
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In recent articles Evans (1990) and Harrigan and McGregor (1993) (hereafter HM) scrutinized the equilibrium model of migration presented in a 1989 paper by Schachter and Althaus. This model used standard microeconomics to analyze gross interregional migration flows based on the assumption that gross flows are in approximate equilibrium. HM criticized the model as theoretically untenable, while Evans summoned empirical as well as theoretical objections. HM claimed that equilibrium of gross migration flows could be ruled out on theoretical grounds. They argued that the absence of net migration requires that either all regions have equal populations or that unsustainable regional migration propensities must obtain. In fact some moves are inter- and other are intraregional. It does not follow, however, that the number of interregional migrants will be larger for the more populous region. Alternatively, a country could be divided into a large number of small regions that have equal populations. With uniform propensities to move, each of these analytical regions would experience in equilibrium zero net migration. Hence, the condition that net migration equal zero is entirely consistent with unequal distributions of population across regions. The criticisms of Evans were based both on flawed reasoning and on misinterpretation of the results of a number of econometric studies. His reasoning assumed that the existence of demand shifts as found by Goldfarb and Yezer (1987) and Topel (1986) invalidated the equilibrium model. The equilibrium never really obtains exactly, but economic modeling of migration properly begins with a simple equilibrium model of the system. A careful reading of the papers Evans cited in support of his position showed that in fact they affirmed rather than denied the appropriateness of equilibrium modeling. Zero net migration together with nonzero gross migration are not theoretically incompatible with regional heterogeneity of population, wages, or amenities.  相似文献   
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