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121.
A polyphasic tectonic‐fluid system of a fault that involves crystalline and carbonate rocks (Hospital fault, Barcelona Plain) has been inferred from regional to thin section scale observations combined with geochemical analyses. Cathodoluminescence, microprobe analyses and stable isotopy in fracture‐related cements record the circulation of successive alternations of hydrothermal and low‐temperature meteoric fluids linked with three main regional tectonic events. The first event corresponds to the Mesozoic extension, which had two rifting stages, and it is characterized by the independent tectonic activity of two fault segments, namely southern and northern Hospital fault segments. During the Late Permian‐Middle Jurassic rifting, these segments controlled the thickness and distribution of the Triassic sediments. Also, dolomitization was produced in an early stage by Triassic seawater at shallow conditions. During increasing burial, formation of fractures and their dolomite‐related cements took place. Fault activity during the Middle Jurassic–Late Cretaceous rifting was localized in the southern segment, and it was characterized by hydrothermal brines, with temperatures over 180°C, which ascended through this fault segment precipitating quartz, chlorite, and calcite. The second event corresponds to the Paleogene compression (Chattian), which produced exhumation, folding and erosion, favouring the percolation of low‐temperature meteoric fluids which produced the calcitization of the dolostones and of the dolomite cements. The third event is linked with the Neogene extension, where three stages have been identified. During the syn‐rift stage, the southern segment of the Hospital fault grew by tip propagation. In the relay zone, hydrothermal brines with temperature around 140°C upflowed. During the late postrift, the Hospital fault acted as a unique segment and deformation occurred at shallow conditions and under a low‐temperature meteoric regime. Finally, and possibly during the Messinian compression, NW‐SE strike‐slip faults offset the Hospital fault to its current configuration.  相似文献   
122.
This paper addresses the motivations underlying migration decision-making in the case of young university graduates returning to their rural home region in Switzerland. Empirical results show the joint role of social ties, living environment, and job opportunities, although the weight given to each of these factors varies between graduates. Some strategies used by the graduates to cope with a limited labour market are furthermore identified. I argue that internal migrations are far from being the sole consequence of labour market conditions and that a greater appreciation of non-economic issues is needed.  相似文献   
123.
French medical journals take the lead among the 1 385 titles of the statistical survey (15.4%). Efficient tool in communication, with an important publishing market, linked to the rise of medicine in the 19th century, prosperity of medical journals do not only mean rise of specialties. Monthly periodicals dominate quickly the publishing market which is also characterized by complex links between generalist and highly specialized medicine, public health and professional training.  相似文献   
124.
The notion of the “secret cause”, which appears in many classical texts is tied to a particular practice of science and a conception of its methods where the “law” finds itself at the center of the nexus. If certain phenomena appear to escape the law, one is obliged to amend the law through the introduction of a series of “small equations.” If the calculation of probabilities is deployed, this is to precisely reveal causes which are, at their origin, secret, but which will gradually become less so and eventually conform to laws.  相似文献   
125.
Sébastien Breau 《对极》2014,46(1):13-33
The Occupy movement catalyzed public debate on the issue of growing income inequality. This paper examines recent patterns of inequality in Canada, paying particular attention to changes in the characteristics of the top 1% of income earners. At the national level, the gap between the top percentile and the other 99% has widened considerably: in 2006, 11% of the nation's income was concentrated in the hands of top earners (whose mean income of $344,000 is 11 times that of the average Canadian) compared with 7.7% just 15 years earlier. Beneath such national‐level figures lie important geographical differences in the income hierarchy: the thresholds, average incomes and socio‐economic characteristics of the top 1% vary widely across provinces and cities. Among the most important spatial shifts observed is the growing concentration of high‐income groups in energy‐rich Western Canada, where Calgary has become the most unequal city in the country.  相似文献   
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This article presents the results of the excavation of a residence dated between the second and fourth centuries AD, constructed over the ruins of the South Arabian town of Makaynūn, in central Hadramawt (Yemen). The building yielded a large quantity of material including objects proving contacts between the central Hadramawt and regions located to the north‐east, such as central Oman, the Gulf area and India.  相似文献   
129.
Relying on stochastic frontier analysis we propose a methodology to study the technological characteristics and cost efficiency levels related to the provision of public infrastructure for basic utilities. The methodology assumes a cost minimizing behaviour on the part of public officials when planning the construction of local infrastructure, which is represented by way of a flexible translog cost function. Introducing relevant definitions of scale economies, associated with larger numbers of inhabitants and dwellings, as well as economies of density, brought about by reductions in urban dispersion, we analytically determine the optimal population densities for which average cost is minimized. We illustrate our model with the water cycle sector, including water distribution, sewage collection and cleansing of wastewater, and considering data at the municipality level for the Spanish region of Castilla y León. The obtained results indicate potential cost savings in the form of decreasing average costs, as relevant scale and density economies are present, along with large inefficiency levels. Relevant policy guidelines favouring larger and denser urban sizes are drawn, as the observed cost excess is the result of a general suboptimal urban size in terms of population density, and the negative effects of dispersed settlement patterns.  相似文献   
130.
The shift from the linear to the innovation system-based approach has resulted in the emergence of differentiated regional innovation policy. However, certain common presumptions bind these location-specific policies together. The set of information that is used to design these policies and the set of information excluded are fairly similar. The theoretical sections of this paper provide a critical review on the informational basis of regional innovation policy by contrasting the interpretations of the welfare effects of technological change in the utilitarian tradition and in Sen's capability approach. The empirical sections analyse the correspondence of the innovation capacity and welfare (well-being) situation in a Hungarian micro-regional data set. We conclude that the conventional informational basis of innovation policy is too narrow from a welfare perspective. Not only should the differences in the innovation systems, but also the peculiarities of the region's welfare situation be considered during the design of innovation policy.  相似文献   
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