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61.
62.
During the last glacial period, a large part of the Aquitaine basin (southwest France) was a periglacial desert comprising coversands with low-relief dune fields surrounded by loess accumulations. OSL and radiocarbon dates show that the phase of maximum sand deposition coincides with Marine Isotope Stage (MIS) 2. Peats and gleyic palaeosoils intercalated within the sands at some sites indicate that vegetation cover was able to develop locally during short events, possibly D–O interstadials, due to raised groundwater levels in interdunal depressions. Few Palaeolithic sites have been discovered in the coversand area in contrast to the peripheral loess region. Systematic survey along a future highway corridor demonstrates that this paucity of sites is not the result of insufficient survey nor deep site burial, but rather reflects an archaeological reality. This strongly suggests that the sand area was not attractive for hunter–gatherer populations due to its reduced levels of water resources, and available vegetation and animal biomass. The distribution of cultural markers such as art items and projectile points also shows that the coversand area probably acted as a barrier separating two different cultural sub-areas, one in the Pyrenees and Cantabria, the other in the Périgord. As a consequence, the commonly accepted view that southwest France, as a whole, served as a refugia during the cold and arid phases of the Pleistocene should be replaced by a more complex one that reflects the fact that a large part of the territory was almost unoccupied and that human populations were concentrated along alluvial valleys.  相似文献   
63.
A source-to-sink multi-proxy approach has been performed within Lake Paladru (492 m a.s.l., French Prealps) catchment and a 6-m long sediment sequence retrieved from the central lacustrine basin. The combination of minerogenic signal, specific organic markers of autochthonous and allochthonous supply and archaeological data allows the reconstruction of a continuous record of past human disturbances. Over the last 10,000 years, the lacustrine sedimentation was dominated by autochthonous carbonates and the watershed was mostly forest-covered. However, seven phases of higher accumulation rate, soil erosion, algal productivity and landscape disturbances have been identified and dated from 8400 to 7900, 6000 to 4800, 4500 to 3200, 2700 to 2050 cal BP as well as AD 350–850, AD 1250–1850 and after AD 1970. Before 5200 cal BP, soil erosion is interpreted as resulting from climatic deterioration phases towards cooler and wetter conditions. During the Mid-Late Holocene period, erosion fluxes and landscape disturbances are always associated with prehistorical and historical human activities and amplified by climatic oscillations. Such changes in human land-used led to increasing minerogenic supply and nutrients loading that affected lacustrine trophic levels, especially during the last 1600 years. In addition, organic and molecular markers document previously unknown human settlements around Lake Paladru during the Bronze and the Iron Ages.  相似文献   
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This paper shows the results of two passive experiments carried out at the European Volvi test site where a scaled building has been constructed. The first experiment was performed to study the motion of the structure excited by two small earthquakes. For one month, six strong-motion recorders were installed within the structure, at the top and at the basement. The analysis of the deformation of the structure has been assessed by computing the spectral ratio between the top and the bottom, with a special focus on soil-structure interaction. An analytical model was then proposed to reproduce the structure and soil-structure system behaviour. The soil-structure interaction was accounted for by using impedance functions. During the second experiment, we concentrated our efforts on the effect of the building vibration on the surface ground motion. An explosive shot was fired and several strong-motion recorders were installed on the ground close to the structure that allowed us to clearly identify a monochromatic wave coming from the building, in the time and frequency domains. This experiment allows us to demonstrate the non-negligible effect of the soil-structure-soil interaction that may disturb the surrounding ground motion.  相似文献   
66.
Strong ground motion close to a fault can be expected to be very large, so its estimation is essential for human safetv. Although a few strong-motion data exist for the west Eurasian region, we proposed in a previous work [Berge-Thierry et al., 2003] an attenuation relation for spectral acceleration using strong-motion data recorded in west Eurasia (mainly in Europe) and some in the western United States: this relationship was derived for the French Safety Rule, which is applied for seismic hazard assessment at nuclear power plants. In this study, we propose a constraining of the amplitude saturation term related to the proximity of the fault, and an adding of an amplitude saturation term in the regression model. We add, to the data-set previously used to derive the west Eurasian attenuation relationship strong-motions recorded during recent large earth-quakes: the 1995 Hyogo-ken Nanbu (Kobe) event in Japan and the 1999 Kocaeli (Izmit) event in Turkey. The regression analysis, adopted from Fukushima and Tanaka [1990], is non-linear, so an iterative procedure is applied. The determined regression coefficients lead to a prediction of a peak ground acceleration of about 0.7 g for soil site conditions at a fault distance of 0.5 km. The Q coefficient deduced, from the distance coefficient is in agreement with scattering Q models. The introduction of the saturation term leads to significantly lower predictions of average spectral accelerations at short distances as compared with using the Berge-Thierry et al. [2003] empirical model.  相似文献   
67.
In recent years French unemployment organisations have been relatively successful in fusing the energies of the unemployed for political purposes and in harnessing public sympathy for their cause. This achievement has been hailed in some quarters as an example of organisations overcoming political impoverishment. This article argues that the involvement of the organisations in politics has not come without important caveats, both in terms of the political significance of that involvement and in terms of the political ‘militancy’ of unemployed people. The article assesses the political significance of the 20‐odd‐year political activities of French unemployment organisations.  相似文献   
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The book Jeux d’échelles. La microanalyse à l’expérience, which appeard in 1996 under the direction of Jacques Revel, was translated in Italy in 2006 by the Viella editions under the title Giochi di scala. La microstoria alla prova dell’esperienza. This occasion seemed propicious for a historiographic and epistemological return to the microhistorical experience between France and Italy. It had to do with cross reperencing the reflections of a french historian and those of an italian philosopher to seek to place in evidence, from a distance, the theoretical presuppositions of microhistory, and to measure the displacements undergone.  相似文献   
70.
The numerous treatises on reason of State are part of a genre which theorises political actions a posteriori. It is not possible for reason of State to be expressed directly and publicly ? How is it staged by the State itself ? Courtly literature, with its subtle dialectic of imitation and idealization, contains abundant material exemplifying this manifestation as representation, all the more significant when it concerns an interregnum. The minor age of the prince, his crowning and the ceremony of his coming of age are essential moments which are surrounded by the rhetoric of praise and during which the State institutes in the prince both the faculty of reason and its own reason: a panegyric reason of State.  相似文献   
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