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41.
The aim of this work is to characterize the original concrete from Roman buildings for public spectacles, theatre and amphitheatre, from Emerita Augusta, Mérida, Spain. An advanced knowledge of the Roman concrete composition is required for a reliable restoration and preservation of these ancient monuments. The concrete was studied through mineralogical (optical polarized microscopy and X-ray diffraction) and petrophysical (bulk and real density, open porosity to water and Hg, mechanical strength and ultrasonic velocity) analyses. With this work, it is possible to fill the gap that exists in this field and the characterization of the materials used in the Roman concrete from these two buildings, never previously studied, despite the significance of this archaeological ensemble, declared a World Heritage Site by UNESCO in 1993. The results allowed us to determine the composition of the Roman concrete and to infer the provenance of the aggregates used in these monuments.  相似文献   
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An upper molar of a small bat, here described from an early Miocene freshwater lime-stone deposit at Riversleigh, northwestern Queensland, is the oldest record in Australia of the microchiropteran family Vespertilionidae. The new taxon is referred to the cosmopolitan genus Leuconoe, but it does not appear to be closely related to the two extant Australian species of this genus.  相似文献   
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Abstract

This paper aims at analyzing what the author calls the “hidden nexus between” Metz and Schmitt. Relying on a Schmittean reference to Metz, pointing to certain conceptual and theoretical, as well as historical components, the paper argues that it is a shared concern about the mistaken modern — utopian reworking of eschatology. The paper also demonstrates how the more recent Metzean rethinking of the problem of theodicy works further this eschatological theme.  相似文献   
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At Nunalleq, a pre-contact Yup'ik Eskimo village site in Alaska (14th–17th century AD), abundant insect remains from highly organic substrates preserved within permafrost offer a unique opportunity to investigate past ecological and living conditions. This paper presents the preliminary results obtained from the analysis of two samples collected from floor layers in sod houses. The numerous and diverse insect remains highlight the exciting potential of archaeoentomology for reconstructing past ecological conditions, resource exploitation and the use of space at northern hunter–gatherer sites and have permitted the development of a strategy for the future collection of archaeoentomological data at permafrost-preserved sites in Alaska and elsewhere.  相似文献   
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India's oilseeds sector, which includes its coconut economy, experienced drastic changes in the wake of agricultural liberalization in the mid‐1990s. A persistent coconut crisis ‘narrative’ emerged after sharp price declines between 2000 and 2002 in which small farmers in the state of Kerala, India's main coconut producer, were identified as victims of the liberalized importation of cheap palm oil. This article describes this crisis narrative based on a literature review of academic and official reports, and challenges its problem analysis by juxtaposing it with information from ethnographic research with local farmers and traders. The research indicates that local labour shortages and increased regional competition also had a strong impact on Kerala's coconut market, production and processing, which varied from region to region. Furthermore, small farmers, with their diversified livelihoods, did not recognize a ‘crisis’ as such. Drawing upon the ‘advocacy coalition framework’, the article also indicates reasons for the emergence and persistence of the coconut crisis narrative and points to complex processes of restructuring social space in the age of globalization.  相似文献   
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In the Iberian Peninsula, the copper metallurgy from the Chalcolithic to the Middle Bronze Age (MBA) was mostly characterized by low arsenic contents. A collection of 53 MBA artefacts from southern Portugal was analysed by micro‐EDXRF, optical microscopy, SEM–EDS and Vickers to investigate the metal composition and manufacture. No technological distinction was found between artefacts from domestic and funerary contexts, which were radiocarbon‐dated to 2000–1500 cal bc . The arsenic contents of almost 100 MBA artefacts from this region, including the above‐mentioned set, have a Gaussian distribution with a high average (3.9 wt% As). Possible explanations are discussed for this distinctive metallurgy at the south‐western end of the Iberian Peninsula.  相似文献   
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