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Over the last decade, a long-running archaeological project in the Guadalquivir Basin (Spain) has identified the emergence (c. 3000 BC) and collapse (between c. 2500 and c. 2300 BC) of a regional inter-settlement hierarchical system centred on the south-western Pyrite Belt and the Lower Guadalquivir Basin.  相似文献   
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Radiocarbon dates on marine shells have not been used as extensively as charcoal or bone dates for the setting up of absolute chronologies because interpreting these dates is complicated by the marine radiocarbon reservoir effect. Nevertheless marine shellfish were used widely at least during the Holocene and their shells are abundant and usually well preserved in archaeological deposits located near shorelines. Consequently prior research concerning the oceanographic conditions and the marine radiocarbon reservoir effect of a particular coastal area is needed in order to set up reliable chronologies for that region. Values of regional marine radiocarbon reservoir effect – ΔR – of coastal waters off Atlantic Iberia, some of its variability along the Holocene and its correlation with the upwelling phenomenon were determined during previous research. More data related to the ΔR values for western Portuguese coastal waters during the Late Neolithic and the Chalcolithic, a time interval badly sampled in previous research, were recently obtained. These values can be compared with ΔR values already determined for the Gulf of Cadiz. Besides the importance of these values for a better knowledge of the palaeoceanography and palaeoclimatology of Atlantic Iberia, from now on archaeologists can set up reliable chronologies for Late Neolithic and Chalcolithic contexts using marine shell samples of that origin for radiocarbon dating.  相似文献   
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In this paper, we explore regional innovation in the use of varieties of algae as inputs to industrial processes. It is important to understand that algae are one of nature's most bountiful products, with an almost infinite variety of applications. Algae have received prominence in the research literature because of the strong evidence that they can make a major contribution to the production and—importantly—storage of renewable energy. Following the introduction to this paper, Section 2 reviews the nature and application of algae in two main aspects of clean energy production: first as biogasolene or biodiesel; second as large-scale storage batteries for electricity. The latter is particularly important as one classic deficiency of electricity is the difficulty in storing it for lengthy periods other than in short-life batteries. However (Section 3), there are other uses for algae, ranging from aquaculture to medicine and the production of cosmetics. In the southwest corner of the Iberian Peninsula, between Faro in Portugal through Huelva to Cadiz in Spain, is a significant research and commercial algae production zone. The paper describes the key system elements in play in this trans-border innovation network and considers prospects for new path creation towards biofuels, the main research and application centres for which are in the San Francisco Bay Area in California. Conclusions and recommendations for policy action are then drawn.  相似文献   
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The first Miocene records of silicified fossil woods from the Mariño Formation, Potrerillos area, Andes Precordillera, Mendoza province, Argentina are described. Rhaphithamnoxylon artabeae gen. et sp. nov. is described as the first fossil wood referable to Verbenaceae from Argentina. This new fossil species is related to extant Rhaphithamnus Miers, sharing the following anatomical features: diffuse porosity, distinct growth ring boundaries, numerous small to very small vessels, commonly in radial multiples, 1–3 seriate rays, and heterocellular and scarce paratracheal axial parenchyma. Rhaphithamnus contains only two extant species: R. spinosus (A.L. Juss.) Moldenke, which occurs in the Valdivian forests of Chile and Argentina, and R. venustus (Philippi) Robinson, which is endemic to the Juan Fernández Islands. Representatives of Verbenaceae are distributed predominantly in the Americas from Patagonia (Argentina) to Canada, and they are inferred to have originated in South America. The fossil wood described herein provides new age and geographical constraints on the raphithanoid lineage within Verbenaceae. Other fossil woods recorded from the Mariño level are retained under open nomenclature, as they possess a combination of mostly solitary broad vessels, and smaller vessels in radial multiples or in clusters, with numerous, vasicentric to confluent axial parenchyma, and heterocellular, high rays. Thus, they have features akin to dicotyledonous lianas or vine-like or small shrub species.  相似文献   
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The paleopathological record of neoplastic conditions in the past is considered scarce. The detection of tumours in ancient populations is hindered by the quality and quantity of signs visible on the skeleton, the methodological approach, the preservation of remains, and by difficulties of differential diagnosis. The aims of this paper are to report the extensive and multiple osteolytic lesions observed in an adult male and to discuss the possible etiology of these lesions. The individual, a 71‐year‐old male who died in 1932, is part of the Coimbra Identified Skeletal Collection. Records indicate that he died of a ‘heart lesion’. The present study used macroscopic, radiological, and computerized tomography examinations to analyse the skeletal remains of the individual number 439. The type and pattern of the lesions detected, which were most prominent on the skull, were compared with both clinical and paleopathological diagnostic criteria for different nosologic groups. The differential diagnosis addresses problems expressed both in clinical and in paleopathological literature with regard to the difficulties in distinguishing metastatic tumours from multiple myeloma. The nature of the lesions represented by this individual precludes an exact diagnosis. Therefore, we employed a broader category, neoplastic condition, instead of choosing a more specific diagnosis that would likely have resulted in a misdiagnosis due to overlapping features on this individual's condition. Further investigations are necessary to establish more replicable indicators and to improve confidence in retrospective diagnosis of these types of conditions. Copyright © 2011 John Wiley & Sons, Ltd.  相似文献   
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