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The notions of risk and safety which play a conspicuous role in the regulation of toxic substances have shown a markedly different evolution in France and the United States. American law has moved toward the development of statutory criteria of risk assessment, balancing both the costs and benefits of regulation, while the French legislator has consistently avoided a substantive elaboration of safety concepts through legal texts. This contrast is documented and its implications for the discretionary authority of regulating agencies discussed. Divergent national patterns are explained with reference to four factors distinguishing the legal and political systems of the two countries.  相似文献   
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A decade ago Simmons (1968) reviewed studies in "an important, but relatively neglected, aspect of migration, namely changes in residence that take place within a city." Since the appearance of Simmons' review intra-urban residential mobility has generated a burgeoning literature underpinned by the assumption that it is a significant mechanism contributing to the structuring of urban space. The literature focuses principally on residential relocation and its identification as a process rather than as a set of events to be explained. Central to the process orientation is the assumption that changes of residence are the expression of a set of decisions made by households. The major deficiency of the literature to date is its failure to specify an appropriate context within which to analyse such decisions.  相似文献   
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Population decline is a key contemporary demographic challenge. Previous work has measured the national extent of population decline, and we know that it is more acute in Japan and Eastern Europe and is set to accelerate across many industrialized countries. Yet, little is known about the population trajectories leading to current trends of depopulation and their underpinning demographic and contextual factors. To address this gap, we aim to identify and characterize the different trajectories of depopulation in Spain from 2000 to 2020 at the small area level using sequence analysis, spatial autocorrelation analysis, decomposition techniques, and multinomial logistic modeling. We show that while Spain recorded an overall 17.2% national population growth between 2000 and 2020, 63% of municipalities experienced depopulation. We identify six trajectories of population decline, with a well-defined northwest-south divide. These trajectories include mostly rural municipalities, but also certain small- and medium-sized cities. Natural decline comprises the main demographic component underpinning differences in the extent of depopulation across trajectories, and international migration plays an important role in explaining transitions to decline since the financial crisis of 2008. Small and old populations, and, to a lesser extent, remoteness from cities are key features characterizing areas of high decline.  相似文献   
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This paper discusses the politics of the material commemoration of mass crime, with a focus on the Ovaherero and Nama descendants of the victims of a 1904–1908 mass ethnic killing in German Southwest Africa. My approach to monuments emphasises their place as artefacts that mark changes of regime after war or revolution, and as focal points of resistance to state regimes of commemoration. Tracing the material forms of memorialisation in Germany reveals the significance of both a ‘remembrance culture’ of the Holocaust and, at the same time, resistance to recognition of the Ovaherero/Nama genocide. In Namibia, the success of the Ovaherero/Nama activist campaign in Germany prompted the government to shift positions and take up the cause of genocide remembrance, asking Germany to officially recognise that its actions constituted genocide, to issue a formal apology and to pay reparations. By framing the mass violence of imperial Germany in terms of its enduring legacy in heritage, Ovaherero and Nama activists and their supporters were able to cross into different geographies of commemoration and bring distant wrongs, without living witnesses, into the present.  相似文献   
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This paper presents dental morphological data of Neolithic, Chalcolithic and Bronze Age populations from the Catalan Pre-Pyrenean area. The Neolithic group, in particular, differs from those of surrounding areas in its funerary culture: the building of cists, which is not present in the Sepulcres de Fossa Culture. A minimum number of 118 individuals from this area were studied for this work, and the data were compared with those of other Iberian and European groups. The results indicate that the two micro-regional groups from the Catalan area (Pre-Pyrenean and Pre-Coastal) were biologically different during the Neolithic and the Chalcolithic, but not in the Bronze Age, when they also appeared to be more homogeneous culturally. In addition, both areas differ biologically from coetaneous Italian groups, although those closer to the coast show slightly smaller differences. Finally, the Bronze Age groups also present fewer differences with regard to the Italian Bronze Age’s group. Therefore, the results suggest that the Catalan Neolithic population had two separate origins, related to cultural patterns, and that differences between the groups decreased within time, probably due to trade-related activities. Moreover, the fact that the difference with Italian populations decreased during the Bronze Age suggests major population movements through the Mediterranean that would affect the biological composition of the human groups.  相似文献   
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In a previous article, we presented an innovative method to analyze cut marks produced with metal tools on animal bones from a metrical and tridimensional perspective (Maté-González et al. 2015). Such analysis developed a low-cost alternative technique to traditional microscopic methods for the tridimensional reconstruction of marks, using their measurements and sections. This article presents the results of an experimental study to test this photogrammetric and morphometric method for differentiating cut marks generated with metal, flint, and quartzite flakes. The results indicate statistically significant differences among cut marks produced by these three types of raw material. These results encourage the application of this method to archeological assemblages in order to establish a link between carcass processing and lithic reduction sequences on different raw materials and also to define the kind of tools used during butchery.  相似文献   
139.
Torres-Martínez, M.A., Sour-Tovar, F. & Barragán, R., November 2017. Kukulkanus, a new genus of buxtoniin brachiopod from the Artinskian–Kungurian (Early Permian) of Mexico. Alcheringa 42, 268–276. ISSN 0311–5518.

Kukulkanus is the first genus of the tribe Buxtoniini recorded from rocks of the late Cisuralian (Artinskian–Kungurian). The Early Permian (Cisuralian) outcrops of the Santa Rosa Group, from southeastern Chiapas, are one of the most important marine Palaeozoic successions of Mexico. The Artinskian–Kungurian Paso Hondo Formation is the youngest unit in the succession and is dominated by massive limestone. Different marine invertebrates deposited in massive calcareous rocks characterize this formation. The buxtoniin Kukulkanus spinosus gen. et sp. nov. is reported from a single bed within the unit. The outcrops are located in southeastern Chiapas, very near the Guatemala–Mexico border. The lithological features and the preservation of fossils indicate that the fossil-bearing rocks were deposited in a low-energy open-waters paleoenvironment over the continental platform. Fusulinids, cephalopods and brachiopods previously described for the Paso Hondo Formation have been correlated with faunas of different coeval localities from Texas, New Mexico, Coahuila, Chiapas and Venezuela, regions that form part of the biotic Grandian Palaeo-Province.

Miguel A. Torres-Martínez [] Departamento de Paleontología, Instituto de Geología, Circuito de la Investigación Científica, Avenida Universidad No. 3000. Colonia Universidad Nacional Autónoma de México, Delegación Coyoacán, Cd. Mx. C.P. 04510, Mexico. Francisco Sour-Tovar [] Museo de Paleontología, Facultad de Ciencias, Universidad Nacional Autónoma de México. Av. Universidad No. 3000, Colonia Universidad Nacional Autónoma de México, Delegación Coyoacán, Cd. Mx. C.P. 04510, Mexico. Ricardo Barragán [] Departamento de Paleontología, Instituto de Geología, Circuito de la Investigación Científica, Avenida Universidad No. 3000. Colonia Universidad Nacional Autónoma de México, Delegación Coyoacán, Cd. Mx. C.P. 04510, Mexico.  相似文献   

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