1000 resultados para O52 - Europe


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While it has been widely suggested that freshwater fishes from East Asia invaded the western Palaearctic, details about this process are largely unknown. Here, using the cytochrome b gene, we evaluated the phylogenetic relationships of a small group of Eurasian primary freshwater fishes (Cobitidae), which are widely distributed and species rich in East Asia and Europe, with the purpose of inferring their invasion process of Europe from East Asia. Though phylogenetic relationships of cobitids were not well resolved, our analysis could identify three sister groups formed by the European and East Asian cobitids, which brought new insights into the biogeography of the genera Cobitis, Misgurnus, and Sabanejewia. The present results support the view that Asian cobitid fishes may have invaded Europe at least five times independently, and once reverse colonization of European cobitids to East Asia could also be found. Ancestral Sabanejewia might have been the first cobitids to cross Siberia and invade the EMZS (Euro-Mediterranean zoogeographic subregion) about 33.54 million years ago (MYA). One lineage of Cobitis and the ancestor of Misgurnus fossilis (Linnaeus) almost in the same time invaded the Europe, responding to 16.71 MYA and 16.59 MYA, respectively. Three different lineages of Cobitis were found to have invaded the EMZS from East Asia, and once reverse invasion to East Asia occurred to one subclade of European Cobitis. And our data also suggest that the diversity of East Asian cobitid fishes, especially of the genus Cobitis, is greatly underestimated.

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Interspecific symbiotic relationships involve a complex network of interactions, and understanding their outcome requires quantification of the costs and benefits to both partners. We experimentally investigated the costs and benefits in the relationship between European bitterling fish (Rhodeus sericeus) and freshwater mussels that are used by R. sericeus for oviposition. This relationship has hitherto been thought mutualistic, on the premise that R. sericeus use mussels as foster parents of their embryos while mussels use R. sericeus as hosts for their larvae. We demonstrate that R. sericeus is a parasite of European mussels, because it (i) avoids the cost of infection by mussel larvae and (ii) imposes a direct cost on mussels. Our experiments also indicate a potential coevolutionary arms race between bitterling fishes and their mussel hosts; the outcome of this relationship may differ between Asia, the centre of distribution of bitterling fishes, and Europe where they have recently invaded.

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The development of long-length, high current density Bi2Sr 2CaCu2Ox wires and (RE)Ba2Cu 3Oy coated conductors has now advanced such that superconducting magnets for energy applications and high field applications are progressing rapidly. Europe, along with China, Korea the US and Japan is an important player in the development and exploitation of High Temperature Superconductors in practical applications. © 2013 IEEE.

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Inferring how the Pleistocene climate oscillations have repopulated the extant population structure of Chondrus crispus Stackh. in the North Atlantic Ocean is important both for our understanding of the glacial episode promoting diversification and for the conservation and development of marine organisms. C. crispus is an ecologically and commercially important red seaweed with broad distributions in the North Atlantic. Here, we employed both partial mtDNA Cox1 and nrDNA internal transcribed spacer region 2 (ITS2) sequences to explore the genetic structure of 17 C. crispus populations from this area. Twenty-eight and 30 haplotypes were inferred from these two markers, respectively. Analysis of molecular variance (AMOVA) and of the population statistic Theta(ST) not only revealed significant genetic structure within C. crispus populations but also detected significant levels of genetic subdivision among and within populations in the North Atlantic. On the basis of high haplotype diversity and the presence of endemic haplotypes, we postulate that C. crispus had survived in Pleistocene glacial refugia in the northeast Atlantic, such as the English Channel and the northwestern Iberian Peninsula. We also hypothesize that C. crispus from the English Channel refugium repopulated most of northeastern Europe and recolonized northeastern North America in the Late Pleistocene. The observed phylogeographic pattern of C. crispus populations is in agreement with a scenario in which severe Quaternary glaciations influenced the genetic structure of North Atlantic marine organisms with contiguous population expansion and locally restricted gene flow coupled with a transatlantic dispersal in the Late Pleistocene.

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This paper is a concise explanation of the normative background to strength grading in Europe, addressing important aspects that are commonly misunderstood by structural engineers and timber researchers. It also highlights changes that are being made to the standards to: incorporate requirements of the construction products regulations; add improvements to the system to accommodate the latest knowledge and technology; and widen the application of the standards. Where designs need to be optimised, there is an opportunity to use the system more intelligently, in combination with the latest technology, to better fit design values to the true properties of the timber resource. This can bring a design enhancement equivalent to effort improving other aspects of the structure, such as connectors and reinforcement. Parallel to this, researchers working on other aspects of structural improvement need to understand what grades really mean in respect of the properties of the timber, in order to correctly analyse the results of testing. It is also useful to know how techniques used in grading can assist with material properties characterisation for research. The amount of destructive testing involved in establishing machine grading settings and visual grading assignments presents a barrier to greater use of local timber, and diversification of commercial species, so it is important that any researcher assessing the properties of such species should consider, from the outset, doing the research in a way that can contribute to a grading dataset at a later date. This paper provides an overview of what is required for this.

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Grattan, J. Durand, M. Taylor, S., Illness and elevated Human Mortality in Europe Coincident with the Laki fissure eruption. In: 'Volcanic Degassing: Geological Society, Special Publication 213', Oppenheimer, C., Pyle, D.M. and Barclay, J. (eds). Geological Society, London, Special Publications, 410-414, 2003.

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Odello, Marco, The Organization for Security and Co-operation in Europe and European Security Law, In: European Security Law, Oxford University Press, pp. 295-328, 2007. RAE2008

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Gunning, Jeroen. 'Terrorism, Charities and Diasporas: Contrasting the fundraising practices of Hamas and al Qaeda among Muslims in Europe', In: Countering the Financing of Terrorism (New York: Routledge, 2007), pp.93-125 RAE2008

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Scully, Roger, Farrell, David, Representing Europe's Citizens? Electoral Institutions and the Failure of Parliamentary Representation (Oxford: Oxford University Press, 2007), pp.xiii+230 RAE2008

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Hughes, R. G., ''Possession is nine tenths of the law': Britain and the boundaries of Eastern Europe since 1945', Diplomacy and Statecraft, (2005) 16(4) pp.723-747 RAE2008

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Korosteleva-Polglase, Elena, 'Can theories of social capital explain dissenting patterns of engagement in the new Europe?', Contemporary Politics, (2006) 12(2) pp.175-191 RAE2008

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Sims-Williams, P. (2006). Ancient Celtic Place-Names in Europe and Asia Minor: Publications of the Philological Society, 39. Oxford: Blackwell Publishing. RAE2008

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This paper is critical analysis of book by Anna Sosnowska, "Zrozumieć zacofanie. Spory historyków o Europę Wschodnią (1947-1994)" [To Understand Backwardness: Historians' Deabates about Eastern Europe (1947-1994)]. Warszawa 2004.

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The aim of this paper is analyse the notion of Central Europe used in historiography. The author reconstructs different meanings of this term used in the works of George Schopflin, Peter Burke, Oskar Halecki, Piotr Wandycz. This notion has not only geographic but also social and historical meaning.