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ABSTRACT

Considerable archaeobotanical datasets describe cereal cultivation in north-eastern France, from the Iron Age to the Roman period. This study aims to complement these by using stable isotope analysis on charred cereal grains. Soil fertility was investigated through δ15N and δ13C analyses of 1480 charred cereal grains, dated from the Late La Tène to the Late Antiquity periods. In the Île-de-France, charred grain Δ13C values suggested good hydric conditions, with drier episodes in the 1st and 3rd century AD; while in Champagne, the lower Δ13C values for spelt reflect the lower water holding capacity of the chalky soils. A wide range of cereal δ15N values (0.8–8.7‰) implies a wide range of soil fertility conditions. Jouars-Pontchartrain and Palaiseau (Île-de-France) yielded the highest cereal δ15N values, whereas Acy-Romance (Champagne) delivered among the lowest. From these three sites, the δ15N values of red deer bone collagen were used to estimate the reference δ15N values for unmanured plants. Unlike in Acy-Romance, there were significant differences in Palaiseau and Jouars-Pontchartrain, indicating that the cultivated cereals inherited their high δ15N values from manured soil. At Jouars-Pontchartrain, the δ15N value (almost 9‰) suggested a high trophic level manuring source, possibly from pig and/or human faeces.  相似文献   
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We apply GIS techniques to analyze a carefully selected database of 93 Early Neolithic sites in the Iberian Peninsula. This allows us to study the spatial dynamics of the Neolithic transition in Iberia. We study how the Neolithic was introduced into the peninsula in order to test the hypothesis that the Neolithic was introduced almost simultaneously from two sources: one at the northeast (via the Mediterranean coast) and another one at the south (possibly from Northern Africa). We also analyze how the expansion of the Neolithic transition took place within the Iberian Peninsula and measure local rates of spread in order to identify regions with fast and slow rates (such as the slowdown at the Cantabrian coast). In addition, we attempt to reproduce the main results obtained from the GIS analysis by applying reaction–dispersal models to the expansion of the Neolithic transition in the Iberian Peninsula. We conclude that a model with two sources is a reasonable assumption that agrees better with the archaeological data available at present than a model with a single source.  相似文献   
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This article discusses the legacy of Amílcar Cabral. The main question it deals with is how to read Cabral today when the system that prompted the emergence of his theory, colonialism, is no longer there. The main argument of this article is, therefore, that a disjuncture exists in the ways Cabral is discussed today. Cabral was certainly a great nationalist and revolutionary, and his contribution crucial for the ways in which revolution in Africa has been apprehended. However, his theoretical contribution should be ascertained alongside the analyses of the realities his emancipatory project addressed. Basically, this article suggests a reading of Cabral's theory in the context of the practices and context his theory was addressing. For doing this, this article examines the main tenets of Cabral's theory, on nationalism, alongside the responses the Portuguese had come up with under the rubric of counter-insurgency strategies. The contribution this article tries to put forward is that critical purchase in reading Cabral today has to take into account the complexities of the anticolonial past that brought us to our postcolonial present.  相似文献   
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Several authors agree that stone surface consolidation works should not significantly alter original mechanical and hygrometric properties of the stones in order to avoid differential stress between the consolidated and non-consolidated parts. Specific limitedly destructive methodologies have been developed for assessing the variation in both mechanical and hygrometric properties, but they require preliminary calibration procedures that are very costly to adopt in terms of both time and money. This research study describes an analytical and experimental procedure aimed at obtaining the necessary hygrometric and mechanical characterization of natural and/or artificial stone, before and after consolidation works, by simply assessing the variation in the distribution of the porous structure.  相似文献   
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This article discusses the relation between ethnography and underexposure of memory. Displaying similar characteristics, the ethnographies we developed in Portugal and Chile dealt precisely with this thematic in different chronological periods. We are going to point out our fieldwork convergences, specifically in what concerns the data recollection process.  相似文献   
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The most serious form of degradation of historical azulejos is the spall of the glaze and it is widely accepted that the crystallization of salts dissolved in water circulating in the masonry is its main cause. This article reports the results of an accelerated aging test aimed at studying the physical deterioration of azulejos caused by cycles of dissolution and re-crystallization of sodium chloride (NaCl). Experiments were carried out on 26 Portuguese azulejos from the 17th–19th century, some of which with original manufacturing defects or with varying degrees of previous decay.

The results of 75 cycles over 18 months did not verify that the action of NaCl could trigger an accelerated loss of glaze in a healthy azulejo. Furthermore, the results lead to the induction that there must be other, eventually concurring, causes for the spall of glaze than a simple challenge with salts that crystallize by evaporation.  相似文献   

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