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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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In the last 15 years, the regional scale was used to implement innovation strategies in European Union. Departing from the discussion of the relevance of innovation policy at the regional level, the article benefits from the knowledge production function framework to estimate patterns considering 175 European regions. It is intended to understand whether regional innovation strategies developed and applied between 1994 and 2001 were successful at an aggregated level in contributing for knowledge creation measured in terms of patents and high technology patents. The results underline the relevance of private R&D expenditure and medium and high technology employment to increase patent numbers. The models suggest also that administrative regionalization may be important to regional innovation and that the creation and implementation of a regional strategy have a positive contribution for high tech innovation.  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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