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In the Amazon Basin, within a landscape of infertile soils, fertile Anthrosols of pre-Columbian origin occur (Amazonian Dark Earths or terra preta de Índio). These soils are characterized by high amounts of charred organic matter (black carbon, biochar) and high nutrient stocks. Frequently, they were considered as sign for intensive landscape domestication by way of sedentary agriculture and as sign for large settlements in pre-Columbian Amazonia. Beyond the archaeological interest in Amazonian Dark Earths, they increasingly receive attention because it is assumed that they could serve as a model for sustainable agriculture in the humid tropics (terra preta nova). Both questions lack information about the pre-Columbian practices which were responsible for the genesis of Amazonian Dark Earths. It has often been hypothesized that deposition of faeces could have contributed to the high nutrient stocks in these soils, but no study has focussed on this question yet. We analyzed the biomarkers for faeces 5β-stanols as well as their precursors and their 5α-isomers in Amazonian Dark Earths and reference soils to investigate the input of faeces into Amazonian Dark Earths. Using Amazonian Dark Earths as example, we discuss the application of threshold values for specific stanols to evaluate faeces deposition in archaeological soils and demonstrate an alternative approach which is based on a comparison of the concentration patterns of 5β-stanols with the concentration patterns of their precursors and their 5α-isomers as well as with local backgrounds. The concentration patterns of sterols show that faeces were deposited on Amazonian Dark Earths.  相似文献   
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The East African coast is a rich domain for underwater cultural heritage, whose archaeological remains are only beginning to reveal the extent of indigenous nautical technology, regional and international social contacts, and far-reaching maritime trade routes sailed for millennia. The diversity of remains found under water range from cultures up and down the East African coastline to further afield: from China, points surrounding the Indian Ocean, to the Persian Gulf, Middle East and Europe. In Mozambique, important steps to investigate and preserve this heritage have been taken over the last 20?years by several groups of local scholars in collaboration with international research institutions. However, this heritage, especially that which lies along the northern Mozambique coast, has also been subjected to extensive and serious disturbance by commercially-oriented salvage programs. These salvage activities have not only had a very negative impact on the state of the cultural resources themselves, but have also prevented the access of legitimate scholars to these resources??particularly grave is the intervention at Mozambique Island, a UNESCO World Heritage Site. Among the meritorious efforts to mitigate this situation, in Mozambique and world-wide, the 2001 UNESCO Convention for the Protection of the Underwater Cultural Heritage is an outstanding initiative and needs to be ratified by Mozambique and other East African states.  相似文献   
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Although there is a considerable amount of empirical evidence on inter-firm collaborations within technology-based industries, there are only a few works focussing on R&D cooperation by low-tech firms, especially small and medium-sized enterprises (SMEs). Providing further and new evidence based on a recently built database of CRAFT projects, this study analyses the relationship between technology and proximity in international R&D networks using HOMALS and statistical cluster techniques. The resulting typology of international cooperative R&D projects highlights that successful international cooperative R&D projects are both culturally/geographically closer and distant. Moreover, and quite interestingly, geographically distant projects are technologically more advanced whereas those located near each other are essentially low-tech. Such evidence is likely to reflect the tacit-codified knowledge debate boosted recently by the information and communication technology (ICT) “revolution” emphasized by the prophets of the “Death of Distance” and the “End of Geography”.  相似文献   
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Angoche was an important historic trading port on the northern Mozambique coast. A maritime archaeological survey was undertaken of the islands and mainland to study Swahili trade, clarify the sequence of settlement development and record the exploitation of resources during the medieval and post-medieval periods. Previous archaeological investigations have revealed local ceramics from the early second millennium AD and imports from the late fifteenth century. According to oral traditions and ancient sources, Angoche’s growth is associated with the arrival of coastal settlers from Kilwa in 1485. The survey revealed evidence for occupation dating from c. AD 500 and trading evidence from the late first millennium AD. Artefacts from the thirteenth to sixteenth century on the islands are similar to those found at Kilwa and Sofala, which shows a link to Kilwa earlier than the oral traditions and the name of one of the Angoche Islands ‘Quilua’, is Kilwa in Portuguese. The islands are well resourced in terms of rice, mangrove wood, seafood and farmland and offer sheltered inlets and access to the coastal trade route. The name of Angoche relates to a port of call and the presence of ninth-tenth-century- storage vessels from southern Iran supports this theory. Traded glass and ceramic artifacts and beads increase from the late medieval period revealing that Angoche became an important and wealthy entrepôt. The lack of coral limestone and reef coral, on the sandy Angoche Islands, indicates some building materials would have had to have been imported. Although many buildings would have been made of wood, some stone ruins are likely to have been demolished and burnt to make lime. The original stratigraphy of many sites has been destroyed by aeolian and marine processes but the survey has shown that valuable information on settlement location and ethnographic practices can still be recovered.  相似文献   
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Taking into account the course of cultural policy in democratic Portugal, and against the backdrop of the international crisis of 2008 and the sovereign debt crisis of 2011, this article seeks to interpret recent changes in the cultural sector in Portugal. Using both qualitative and quantitative methods it focuses on three main aspects: institutionalisation of democratic cultural policy; government funding; cultural organizations and facilities. The 2008 crisis put an end to a period in which investment tended to grow. We place Portugal in the broader European context, concluding that the Portuguese cultural scene may once again diverge from that of other European countries.  相似文献   
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This paper is focused on a spectroscopic study of some pottery shards from an archaeological site in Syracuse (Sicily, Southern Italy), dating back to the Hellenistic–Roman period. Structural characterization was performed at different scales of observation, i.e. from macroscopic to mesoscopic. The main goal was to point out the potentiality of the small angle neutron scattering (SANS) technique as a non-invasive analytical tool in archaeometry, also in conjunction with other, more usual, methodologies. Correlation of experimental data, i.e. macroscopic typology and texture, obtained from petrographic analysis, and radius of gyration and fractal dimension of the interfaces of the mesoscopic aggregates obtained using SANS, together with mineralogical X-ray diffraction (XRD) and scanning electron microscopy (SEM) analysis, allowed hypotheses to be made on the production technology of the investigated samples.  相似文献   
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