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11.
AbstractAcross most of Europe, the countryside seems to show a polarized development in which large districts are depopulating, while certain areas, mainly around big- and mid-sized cities, are increasing in population. The latter development is often described in concepts of “rural gentrification” and “rurbanization”, symbolizing a transformation of rural communities to communities with urban values and lifestyles. Most studies of the effects of these processes have focused on social and cultural consequences, as e.g. the displacements of lower-income households with higher-income residents and of rural culture and values with urban ones. This paper examines the phenomenon from another perspective, namely the effects of the “rurbanization” processes on countryside's labour markets and economic life. This paper aims at analysing the determinants of net migration to rural areas in general and to different types of regions, and the impacts of in-migration on rural labour markets, self-employment and other socio-economic conditions in Sweden for the period of 2003–2005. We find that net migration into rural areas increases with the size of adjacent local and regional centres, whereas net migration decreases with the average commuting distance of workers in the rural areas. When comparing in-migrants to rural areas with rural area stayers, our results indicate that the former has lower incomes, a lower employment ratio and a lower degree of entrepreneurial activities. These differences could—at least partly—be explained by the fact that rural area stayers were on average 6 years older than rural area in-migrants, i.e. the two groups were in different stages of their life cycles. 相似文献
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Nikolaos Zacharias Alexander Schwedt Jaume Buxeda i Garrigós Christodoulos T. Michael Hans Mommsen Vasilis Kilikoglou 《Journal of archaeological science》2007
In luminescence dating, the potassium concentration significantly contributes to the dose rate value in the age estimation. Within this study, fine-grain thermoluminescence dating has been applied on sherds of calcareous pottery of known age, excavated at a Roman site in Mallorca, Spain. For those of the samples that showed signs of severe potassium leaching, according to chemical and mineralogical examination, the thermoluminescence analysis provided overestimated dates. By using the known archaeological age of the samples, a corrected dose rate value can be estimated which provides the potassium concentration averaged for the burial period. Finally, a step-like model can then be used to estimate the fraction of the burial period after which most of the alteration effects took place. 相似文献
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The initial interpretations of motion phenomena are often in terms of eye movements. It reflects a desire to link an objective expression of motion (of the eyes) with a subjective experience of motion. This approach is examined historically with respect to induced motion, motion aftereffects, visual vertigo, autokinetic effects and stroboscopic motion. All but one of these phenomena were initially observed in the natural environment and they have subsequently been studied under laboratory conditions. Eye movements are not correlated with induced motion, the motion aftereffect, or stroboscopic motion, but they do correspond to the direction and extent of visual vertigo. The extent of apparent visual motion in the autokinetic effect far exceeds that of involuntary eye movements but there might be a weak relation between them. If eye movements are to provide a reasonable account of motion illusions then they should apply to all the contours that are visible. This does apply to visual vertigo, but not to induced motion, the motion aftereffect and stroboscopic motion, all of which involve relative motion in a visible display. The autokinetic phenomenon involves the perception of isolated stimuli, and so interpretations in terms of some internal eye movement signals remain sustainable. 相似文献
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Hans Georg K. Gebel 《Arabian Archaeology and Epigraphy》2020,31(1):119-127
This contribution’s broad and in parts essayistic approach to Arabia’s Neolithic is less a discussion of findings than an explicit advocacy for future holistic research strategies. Based on the contribution’s meta-theoretical inputs, it suggests two sets of theses to be tested by the hitherto gained fragmentary information and future research on Arabia’s Neolithic. It aims to encourage an “emancipation” of Arabia’s early to mid-Holocene research from conceptions developed outside its regions, and to identify the Neolithic elements and developments of the Arabian lands by distinguishing incursions from primarily autochthonous and/or autonomous adaptations in their own right. It is suggested that productive lifeways are considered to be the only crucial parameter to testify a Neolithic status. In our view this is the case, provokingly enough, for the productive foraging management of natural resources which attests surplus and pre-planning strategies and contacts with established Neolithic socio-economies. Polylinear incursions and autochthonous adaptations are discussed as the two poles between which early to mid-Holocene developments in Arabia took place. A set of basic and a set of trajectory hypotheses on Arabia’s neolithisation and finally sustainable sedentarisation (reliance on oases economies) is presented, offered as a possible framework for future multi-/ transdisciplinary research. 相似文献
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Neolithic nomadism in south‐east Arabia — strontium and oxygen isotope ratios in human tooth enamel from al‐Buhais 18 and Umm al‐Quwain 2 in the Emirates of Sharjah and Umm al‐Quwain (UAE) 下载免费PDF全文
Human skeletal remains from the Neolithic sites BHS18 in the interior of the Sharjah Emirate and the Neolithic shell midden UAQ2 (Umm al‐Quwain) on the coast of the Persian Gulf (United Arab Emirates, UAE) were analysed for their isotope ratios of strontium (87Sr/86Sr) and oxygen (18O/16O). The results are not in agreement with earlier assumptions about a Neolithic nomadism between inland regions and the south‐eastern coast of the Persian Gulf. Existing evidence of nomadic movements of the people from BHS18 most possibly refers to transhumance within the mountains in the hinterland. The strontium isotope measurements on human skeletons from UAQ2 on the contrary indicate uninterrupted residence of this population on the coast. Nevertheless, evidence was found of individual mobility between inland regions and the coast. 相似文献
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The focus of this article is on product innovations introduced by firms (establishments) and the collaborations they enter into with other firms and organizations in carrying out this activity. The theoretical framework combines innovation theories with the literature on regional innovation systems and the knowledge-based economy. Empirically we have investigated characteristics of collaboration among manufacturing establishments in the region of East Gothia in Sweden, with specific focus on the number of employees involved in the innovation projects, mechanisms of knowledge transfer between organizations, as well as financing and patenting in relation to product innovations. 相似文献