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21.
The analysis of the composition of organic residues present in ancient pottery are an important source of information for archaeologists. The chemical characterisation of these materials gives information on diets, habits, technologies and original use of the vessels.  相似文献   
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Pollen, non-pollen palynomorphs and charcoal from a colluvial soil surrounded by prehistoric petroglyphs (Campo Lameiro, NW Spain) were studied in order to assess the nature of human activities and their impact on Holocene vegetation patterns. Several phases of anthropogenic impact were observed. (i) Between 7.6 and 6.5 ka cal BP, synanthropic taxa (Urtica dioica type, Plantago lanceolata type) and coprophilous fungi (e.g. Sporormiella-type) are indicative of early (pre-agricultural) creation of small patches of pasture using fire, possibly for incipient animal husbandry or as part of a deliberate strategy to improve game availability. Such activities only had a minor effect on the deciduous Quercus-dominated forest established earlier during the Holocene Thermal Maximum. (ii) Between 5.9 and 4.8 ka cal BP a more intense signal indicative of pastoral activity was detected, corresponding to the Neolithic period. (iii) Between 4.8 and 3.4 ka cal BP, which fits within the hypothetical timeframe of petroglyph creation, the synanthropic and humidity (e.g. Cyperaceae, Mougeotia) indicators diminished while charcoal concentration increased, which can be explained by Mid-Holocene cooling/drying (Neoglaciation) in combination with reduced human impact, or by non-pastoral activities in the area possibly in association with the development of the rock art culture, converting pasture to protected open ground through anthropogenic fires. (iv) During the Late Bronze Age and Early Iron Age (3.4–2.5 ka cal BP), grazing pressure and fire regime intensity are high, coinciding with evidence of regional forest regression, despite an amelioration in climate. (v) Later phases, not corresponding to prehistoric rock art contexts, include a phase of heavy grazing and reduced fire frequency (from ca. 2.5 to 1.2 ka cal BP) as well as the near complete elimination of the deciduous woodland, the expansion of ericaceous shrubland and the evidence of local agriculture and afforestation. These results are consistent with earlier studies in the area and highlight the spatial heterogeneity in the vegetation especially during periods of prehistoric anthropogenic interference.  相似文献   
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Performance-based earthquake engineering methodologies often require a probabilistic model of structural demand. Since observations masking the probability distribution of the majority of the data are frequently found, robust estimation methods are proposed to estimate the probabilistic model parameters (i.e., central value and dispersion). The performance of thirty-three robust dispersion estimators is evaluated, for different sample sizes, using the chord rotation, curvature, shear force, and inter-story drift demands obtained after analyzing five reinforced concrete structures under real earthquake records scaled to several intensities. Based on the results, combinations involving dispersion and central value (defined in a companion article) estimators are proposed.  相似文献   
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Abstract. This article analyses the discussion, enactment and characteristics of the Linguistic Policy Act adopted by the Catalan Parliament in 1998, from the point of view of current normative political theory. The main theoretical question is whether its provisions promoting the Catalan language are compatible with the liberal political tradition, considering its different streams. The discussion shows that the main arguments are not different from those used by scholars dealing with issues of national and cultural pluralism in Western democratic societies. Thus, the opponents of the Act tend to rely upon various individual rights‐based arguments taken from classical liberalism. Its advocates, on the other hand, accuse them of neglecting the value of cultural membership, asserted by influential authors within the liberal tradition. Ultimately, the article concludes that this law neither promotes nor allows illiberal practices.  相似文献   
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The colluvial soils of Galicia (NW Spain) are records of Holocene environmental change. In spite of the omnipresence of charcoal fragments in these soils, the effect of fires on the development of the Galician landscape and the potential role of past societies are poorly understood.  相似文献   
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The Northwest of Namibia bears a concentration of rock art that is among the highest in the world. One of the centres is Twyfelfontein, a cluster of sites surrounding a waterhole at the eastern fringe of the Namib Desert, classified as the prime rock engraving site in southern Africa and designated a UNESCO World Heritage Site. Recent prospections in the desert west of Twyfelfontein have resulted in the discovery of engravings and paintings that exceed those at the UNESCO site, both in quantity and quality. Our contribution to this volume in memory of Klavs Randsborg introduces this newly discovered archaeological landscape and discusses the connection between water ‐ a rare commodity in the desert environment ‐ and the rich array of rock art and other archaeological features found here.  相似文献   
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This article addresses the laboratory testing of a full-scale double-T shaped adobe wall, under in-plane horizontal cyclic loading of increasing amplitude, with the aim of contributing to the understanding of the seismic behavior of adobe structures. The wall was built with lime adobes taken from an existing building and mortar with a traditional composition. The behavior of the wall was assessed in terms of: shear stress versus horizontal drift and moment versus rotation relationships; maximum lateral strength; drift and rotation at peak stress; evolution of stiffness, lateral displacements, dissipated energy, and natural frequency; and damage pattern. The wall exhibited brittle behavior and in-plane strength corresponding to 56% of the vertical load. Cracking was observed with an X-shaped pattern whereas no sliding occurred at its base. This research supported the subsequent development of a repair and retrofit solution and also of numerical models to simulate the seismic behavior of two adobe buildings.  相似文献   
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