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61.
The role of coastal resources in the subsistence strategies of Palaeolithic human populations has only recently become an important topic in Old World archaeology. Information on the exploitation of these resources, both as foodstuffs and symbolic elements, can be used to infer the emergence of modern human behaviour as well as to track the diversification and intensification of human diet over time. The excavations carried out at El Cuco rockshelter, located in northern Spain have provided evidence for the exploitation of marine resources during the Early Upper Palaeolithic. The accumulation of Patella shells at El Cuco provides the largest accumulation and the first clear evidence of collection and consumption of molluscs during the Aurignacian on the Atlantic Façade of Europe. A deposit of ornamental shells appeared in a very homogeneous context dated to the Gravettian, suggesting that the shells belonged to the same item. The analysis of this evidence has allowed us to conclude that marine resources were systematically used at least from the beginning of the Upper Palaeolithic in the region. However, a comparison with the Mesolithic shows that intensive shellfish gathering did not occur until the end of the Upper Palaeolithic. Regarding the ornaments, it is interpreted that the identified shell beads were used as social or personal status markers.  相似文献   
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Ferrari, S.M., September 2012. The genera Cryptaulax and Procerithium (Procerithiidae, Caenogastropoda) in the Early Jurassic of Patagonia, Argentina. Alcheringa 36, 325–339. ISSN 0311-5518.

New species of Cryptaulax and Procerithium (Procerithiidae, Caenogastropoda) are reported from the Lower Jurassic (Pliensbachian–Toarcian) marine deposits of west-central Chubut province, Argentinean Patagonia. Three new species are described: Cryptaulax redelii, Procerithium (Rhabdocolpus) patagoniensis and Procerithium (Infacerithum) nodosum; and the diagnoses of Cryptaulax damboreneae Ferrari and Procerithium nulloi (Ferrari) are emended. The new fossils derive from the Mulanguiñeu and Osta Arena formations and expand the known diversity of the Procerithiidae, extending its palaeobioeographical distribution into the South American Jurassic.  相似文献   
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Understanding the pattern of hominin dispersal is a fundamental component of Palaeolithic archaeology and palaeoanthropology. A widely held assumption is that bifacial handaxe (i.e. Acheulean or ‘Mode 2’) technologies evolved in Africa and dispersed into northern and western Eurasia via subsequent hominin migrations. To date, however, few formal tests of this hypothesis have been presented. Here, we use a combination of morphometrics, cultural transmission theory, and a dispersal model drawn from population genetics in order to test this hypothesis. The iterative founder effect (repeated bottlenecking) model is assumed to be supported if a significant inverse relationship is found between geographic distance from source along an estimated dispersal route and within-assemblage variance. The results of our analyses support the hypothesis that Acheulean technologies evolved in Africa and dispersed with migrating hominin populations into northern and western Eurasia under the assumptions of this iterative founder effect model. Based on our results we suggest that the occurrence of certain Mode 1 technologies such as those east of the Movius Line, and some assemblages assigned to the Clactonian of Britain, plausibly represent instances where effective population sizes in colonising populations dropped below levels where Mode 2 technologies could be maintained.  相似文献   
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The paper provides some empirical evidence of the effectiveness of the “open innovation” model in the life science cluster of Emilia Romagna (a region of Italy), comparing the network of R&D collaborative activities in public research organizations (PROs) and the network linked to R&D collaborative activities in private firms. By presenting the main results of a field research in the life science sector in Emilia Romagna, we are contributing to the recent debate focused on the crises of the old “closed innovation” model and the rise of the “open innovation” model. Our survey consists of both primary data deriving from face-to-face interviews with researchers and entrepreneurs, and secondary data extracted from the Internet, the PubMed database, and from the European Patent Office. Our work is based on the analysis of a representative sample of 30 research groups in PROs, 2173 scientific articles published by the interviewed scientists, and a representative sample of 78 private firms.  相似文献   
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The palynoflora of surface samples of glacial deposits from the Guandacol Formation in the Cerro Bola area of the Argentinian Paganzo Basin is documented. The existence of glacial related diamictites in this area has been previously ignored. The fossiliferous levels are located in section B of the formation, which corresponds to the earlier stages of deglaciation. The assemblage contains abundant monosaccate pollen grains whose global incoming is not older than early Namurian (Middle Carboniferous). Many species of this palynoflora are present in equivalent stratigraphic sequences of Argentina and can be referred to Sub-biozone A of the Raistrickia densa-Convolutispora muriornata Biozone (Namurian-Stephanian). New species described here are Cyclogranisporites rinconadensis and Tricidarisporites gutii.  相似文献   
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