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Oscar Fisch 《Journal of regional science》1986,26(1):103-120
The paper interprets a neoclassical model of quality growth in relation to housing technology, reinvestment choice, growth of the stock of shelter, growth with and without architectural design progress, and analyses of the golden rule of quality accumulation in the housing sector. 相似文献
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Oscar Fisch 《Geographical analysis》1991,23(3):261-275
The central objective of this paper is to explore a comprehensive structural modeling approach that extracts analytical density functions answering questions raised by recent empirical studies. 相似文献
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Domestic Pigs in Africa 总被引:1,自引:0,他引:1
Marcel Amills Oscar Ramírez Ofelia Galman-Omitogun Alex Clop 《African Archaeological Review》2013,30(1):73-82
The history of African pig breeds is still controversial due to the relative scarcity of archaeological and genetic data clarifying their origins. While these breeds might descend from Near Eastern pigs entering the continent via Egypt during the Neolithic, Africa may be a primary domestication locus for pigs, as indicated for other species such as cattle and donkeys. In this regard, characterisation of the mitochondrial gene pool of African pig breeds has revealed a very low frequency of Near Eastern alleles, suggesting that, if Fertile Crescent pigs played a part in the foundation of African breeds, their genetic signature has been substantially erased. Interestingly, genetic analysis of western and eastern African pig breeds has revealed a strong phylogeographic pattern, with the latter harbouring Far Eastern alleles at high frequencies. This finding is consistent with data obtained for chickens and confirms that livestock was transported in ancient times, from the Far East to Africa as a consequence of the Indian Ocean trade. European colonisation of Africa also involved the introduction of exotic swine breeds such as Iberian pigs. The confluence of the highly divergent European and Far Eastern Sus scrofa gene pools contributed to significantly enrich the genetic reservoir of African swine breeds, favouring their adaptation to environmental conditions that are often harsh. Conservation of this genetic legacy will be of utmost importance to ensure the prosperity of current resource-based subsistence farming systems in Africa. 相似文献
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Jennie Gamlin Agnes Zenaida Camacho Michelle Ong Therese Hesketh 《Children's Geographies》2015,13(2):212-225
In this paper, we report on a study of the psychosocial effects of child domestic work (CDW) in six countries and the relevance of our findings to international legislation. Our results suggest that CDW is highly heterogeneous. While some young child domestic workers work long hours, suffer physical punishment and are at risk of psychosocial harm, others are able to attend school and benefit from good relationships with their employers and networks of support. Child domestic workers in India and Togo were most at risk of psychosocial harm. We conclude that classification of this employment as hazardous would not be appropriate and could be counterproductive and instead propose that legislation focuses on protective factors such as a social and community support. 相似文献
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Technology is of key importance to the growth of regional firms and economies. Research has shown the association between low technology development or take-up and regional disparities. Hence technology policy is moving closer to the heart of regional policies. European innovation programmes are intended to involve firms, large and small, in international technology research and development networks. The paper focuses on the involvement of Spanish firms in such programmes. Participation tends to be low if business R&D, presence of large firms, and the development of regional innovation systems are also low. Creation of R&D infrastructure through the Structural Funds has now to be prioritized at EU level and also define a new scheme of sectoral priorities in order to support R&D innovation activities in fields diverse from high-tech, if regions are to escape the 'low R&D trap'. 相似文献