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This paper describes the hitherto unreported occurrence of mid‐Holocene mangrove deposits in the Richmond River estuary, southeastern Australia, thereby providing evidence for changes in the distribution and composition of mangrove communities within a subtropical estuarine system during the Holocene. Stratigraphic, radiocarbon and palynological evidence indicates that widespread development of mangrove communities took place in the upstream reaches of the Richmond River estuary during the period 7000 to 6000 years BP. These communities maintained their habitat through substrate aggradation under the conditions of a moderate sea‐level rise, in contrast to other estuaries within the region, which generally experienced the submergence of intertidal substrates. Mangrove species belonging to the family Rhizophoraceae, most likely Bruguiera gymnorrhiza and Rhizophora stylosa, dominated these communities, in strong contrast to contemporary communities, which are dominated by Avicennia marina. Moreover, these mid‐Holocene communities were located a considerable distance upstream of the contemporary occurrences of Rhizophoraceae species within the estuary. The changes in the spatial distribution and composition of mangrove communities parallel the large‐scale evolution of the estuary driven by sea‐level variation. Shallow, buried Pleistocene terraces probably contributed to the regionally unique aggradational response of the mangrove communities and their substrates to a sea‐level rise during mid‐Holocene times.  相似文献   
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This paper reports on the comparative evaluation of traditional and innovative methods for the investigation of mortar technology. Preliminary results of various approaches to determining the mix proportions in lime mortars with carbonate aggregate are presented. Quantitative analysis was tested on ad hoc prepared mortars of known composition containing carbonate aggregates of different origin (travertine and Bath limestone). Wet chemical methods, manual disaggregation and Digital Image Analysis of thin sections and cross‐sections stained with Alizarin Red S were tested. The advantages and drawbacks of the different approaches are discussed, and applications to the analysis of archaeological mortars and plasters are highlighted.  相似文献   
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Much has been made of completing the Single European Market in Europe. Despite movements towards more advanced levels of integration such as currency union, there remains several grey areas in specific industries that are not allowing for open access to the market. These areas include government activities such as electricity and gas along with other industries such as telecommunications. This article sets out to examine whether there is likely to be a free market in these sectors and assesses the progress being made since the introduction of a number of procurement directives post-1998. This will therefore have an influence on land use planning. The article draws on the literature of regulation and industrial organization as well as European integration in order to demonstrate the complexities of these industries and the problems of full compliance with the single market.  相似文献   
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Counterfactualism is a useful process for historians as a thought-experiment because it offers grounds to challenge an unfortunate contemporary historical mindset of assumed, deterministic certainty. This article suggests that the methodological value of counterfactualism may be understood in terms of the three categories of common ahistorical errors that it may help to prevent: the assumptions of indispensability, causality , and inevitability. To support this claim, I survey a series of key counterfactual works and reflections on counterfactualism, arguing that the practice of counterfactualism evolved as both cause and product of an evolving popular assumption of the plasticity of history and the importance of human agency within it. For these reasons, counterfactualism is of particular importance both historically and politically. I conclude that it is time for a methodological re-assessment of the uses of such thought-experiments in history, particularly in light of counterfactualism's developmental relatedness to cultural, technological, and analytical modernity.  相似文献   
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The pigments, binders and execution techniques used by the Nasrids (1238–1492) to polychrome carpentry in the Hall of the Mexuar Palace at the Alhambra (Granada, Spain) were studied using optical microscopy, scanning electron microscopy with EDX analysis, selective staining techniques and gas chromatography – mass spectrometry. This pioneering investigation presents the first results of a research project devoted to filling gaps in the knowledge of Nasrid art, traditionally approached by stylistic studies. Moreover, it is essential for the polychromy conservation of the studied artworks, and will help to clarify historical and painting uncertainties in the Alhambra monument. The palette consists of a limited range of colours: white (lead‐base pigment), red (cinnabar and red lead), blue (lapis lazuli), black (carbon‐based) and false gold (golden tin). Tempera grassa was the painting technique identified. Two types of grounds were used: (i) gypsum in calligraphy decoration for the false gold technique, and (ii) synthetic minium in geometric drawings in carpentry. Organic insulating layers of linseed oil were used between paint strata. Artists applied synthetic minium to protect the wood (Juglans regia and conifer) against attack by xylophages. To lighten the surface darkened by this ground layer, powdered tin was added to achieve a metallic lustre.  相似文献   
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