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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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We describe an archaeo-geophysical investigation performed near the Palo Blanco archaeological site, Catamarca, Argentina. A large area beyond the northern limit of the site was explored with the Ground-Penetrating Radar (GPR) method in order to detect new buildings. The exploration showed signals of mud-walls in a sector that was located relatively far from the previously known buildings. A detailed survey was performed in this sector, and the results showed that the walls belonged to a large dwelling with several rooms. The discovery of this dwelling has considerably extended the size of the site, showing that the dwellings occupied at least twice the originally assumed area. High-density GPR surveys were acquired at different parts of the discovered building in order to resolve complex structures. Interpreted maps of the building were obtained. Different characteristics of the walls were satisfactory determined, in spite of the low contrast of the dielectric constant at their interfaces and the noticeable spatial fluctuations of the signals due to wall collapses.  相似文献   
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This article examines the historical processes that shaped the development of archaeological practice in Angola during the Portuguese colonial period and the aftermath of political independence. Using published works, unpublished reports, and photographic records, we examine the research themes, actors, scholars, and institutions that influenced archaeological research in the country. We also used documents and museum collections in Angola and Portugal to create a GIS database of Angola’s archaeological findings. This study highlights the events, personalities, and priorities that motivated earlier investigations, and the geographical distribution of prehistoric sites. We hope this study will be a resource for guiding future archaeological research in Angola.

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Until the beginning of the twentieth century, history, as a core concept of the political project of modernity, was highly concerned with the future. The many crimes, genocides, and wars perpetuated in the name of historical progress eventually caused unavoidable fractures in the way Western philosophies of history have understood change over time, leading to a depoliticization of the future and a greater emphasis on matters of the present. However, the main claim of the “Historical Futures” project is that the future has not completely disappeared from the focus of historical thinking, and some modalities of the future that have been brought to the attention of historical thought relate to a more-than-human reality. This article aims to confront the prospects of a technological singularity through the eyes of peoples who already live in a world of more-than-human agency. The aim of this confrontation is to create not just an alternative way to think about the future but a stance from which we can explore ways to inhabit and therefore repoliticize historical futures. This article contains a comparative study that has been designed to challenge our technologized imaginations of the future and, at the same time, to infuse the theoretical experiment with contingent historical experiences. Could we consider artificial intelligence as a new historical subject? What about as an agent in a “more-than-human” history? To what extent can we read this new condition through ancient Amerindian notions of time? Traditionally, the relationship between Western anthropocentrism and Amerindian anthropomorphism has been framed in terms of an opposition. We intend to prefigure a less hierarchical and more horizontal relation between systems of thought, one devoid of a fixed center or parameter of reference. Granting the same degree of intellectual dignity to the works of Google engineers and the views of Amazonian shamans, we nevertheless foster an intercultural dialogue (between these two “traditions of reasoning”) about a future in which history can become more-than-human. We introduce potential history as the framework not only to conceptualize Amerindian experiences of time but also to start building an intercultural dialogue that is designed to discuss AI as a historical subject.  相似文献   
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