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Neves, J.P., Anelli, L.E., Pagani, M.A. & Simões, M.G., 2014. Late Palaeozoic South American pectinids revised: biostratigraphical and palaeogeographical implications. Alcheringa 38 ISSN 0311-5518.

A revision of the late Palaeozoic South American pectinid Heteropecten multiscalptus (Thomas) and the establishment of Heteropecten paranaensis sp. nov. have important implications for the relationship between faunal realms within South America. Late Palaeozoic bivalve faunas occur in three distinct realms in South America: a Central Gondwanic Realm with endemic taxa showing affinities to Australia, New Zealand, South Africa and Namibia, a cold Perigondwanic Realm, and a warm Extragondwanic Realm with tethyan-like affinities similar to faunas of the American Midcontinent. In South America, faunas east of the southern Andes belong to the first two realms and previous interpretations of bivalve faunas suggested biocorrelations with those of the Extragondwanic Realm because they shared the taxon Heteropecten multiscalptus (Thomas). A revision of the Peruvian and Brazilian material does not confirm this. Instead, a re-analysis suggests that two species are present, rather than one: Heteropecten multiscalptus in the Cerro Prieto Formation, Amotape Mountains (Peru; Extragondwanic Realm), and Heteropecten paranaensis sp. nov. in the upper part of the Itararé Group, Paraná Basin (Brazil; Central Gondwanic Realm). Thus, the correlation between the late Palaeozoic faunas of the Central Gondwanic and Extragondwanic Realms in South America can no longer be supported. Heteropecten paranaensis sp. nov. lived in a siliciclastic-dominated, cold, epeiric sea of Brazil and Argentina, and is morphologically similar to some Australian species, whereas the Peruvian H. multiscalptus thrived in the warm seas of the Extragondwanic Realm.

Jacqueline P. Neves [], Instituto de Geociências e Ciências Exatas, Universidade Estadual Paulista, Rio Claro campus, SP, Brazil, 13506-900; Luiz E. Anelli [], Instituto de Geociências, Universidade de São Paulo, 05508–080, Brazil; M. Alejandra Pagani, [], CONICET-Museo Paleontológico Egidio Feruglio (MEF), U9100GYO, Chubut, Argentina; Marcello, G. Simões [], Instituto de Biociências, Universidade Estadual Paulista, Botucatu campus, SP, 18618-970, Brazil. Received 19.7.2013; revised 12.11.2013; accepted 19.11.2013  相似文献   
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Southeastern Central Europe is quite rich in finds of progressive Neandertals from Middle Paleolithic contexts and early modern humans associated with evolved Upper Paleolithic (Aurignacian and Pavlovian). There are no human fossils that can be related to the transitional Middle-Upper Paleolithic units (the Bohunician and the Szeletian); thus, from anthropology we know only that the transitional period began with Neandertals and ended with modern humans. The archaeological record is more complex. The Jankovichian industries of Hungary differ from the mostly non-Levallois Middle Paleolithic of Central Europe in the presence of some Levallois; they seem to be technologically related to the Levallois-Leptolithic Bohunician industries of Moravia, dated to 43,000–38,000 B.P., which are the first transitional Upper Paleolithic unit. The appearance of the Szeletian before 42,000 B.P. in Hungary and at about 39,000 in Moravia represents a technological variation of the transition, although retaining marked local Middle Paleolithic elements. The date of the appearance of the typical Aurignacian, the first culture clearly related to modern humans, is unclear, but it certainly developed after 36,000 B.P. and has several dates between 35,000 and 30,000 B.P.  相似文献   
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Based on a qualitative methodology that includes in‐depth interviews with 90 Mexican migrant smugglers and 45 Central American farmworkers, this article analyzes the three separate elements of trafficking in US agriculture, namely acts, means, and purposes. We conclude that some US employers participate in human trafficking by financing or helping to recruit and transport Mexican and Central American migrants to the US by means of “abuse of a position of vulnerability” for the purposes of involuntary servitude, debt bondage, and sex exploitation.  相似文献   
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Abstract

The period from the late 1840s to the early 1870s represented a distinct one in Irish-American politics. This article frames Irish-American nationalists active in this period as nonstate actors seeking to influence the course of U.S. foreign relations to serve their own interests. In particular, it focuses on the activities of the Fenian Brotherhood and an earlier, less well-known organization, the Robert Emmet Club. The actions of both highlighted the looseness of U.S. neutrality legislation and, ultimately, provided a compelling argument for Anglo-American rapprochement. Simultaneously, in the immediate postbellum years, U.S. statesmen had reason to manipulate the Irish question to further their own ends. As Anglo-American relations improved, however, the geopolitical value of Irish nationalism declined; Irish-American nationalists were left marginalized in the calculations of U.S. diplomats.  相似文献   
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Simões, M.G., Quaglio, F., Warren, L., Anelli, L.E., Stone, P., Riccomini, C., Grohmann, C.H. & Chamani, M.A.C. December 2012. Permian non-marine bivalves of the Falkland Islands and their palaeoenvironmental significance. Alcheringa 36, 543–554. ISSN 0311-5518.

We describe the occurrence of non-marine bivalves in exposures of the Middle Permian (Capitanian) Brenton Loch Formation on the southern shore of Choiseul Sound, East Falklands. The bivalves are associated with ichnofossils and were collected from a bed in the upper part of the formation, within a 25 cm thick interval of dark siltstones and mudstones with planar lamination, overlain by massive sandstones. The shells are articulated, with the valves either splayed open or closed. At the top of the succession, mudstone beds nearly 1.5 m above the bivalve-bearing layers yielded well-preserved Glossopteris sp. cf. G. communis leaf fossils. The closed articulated condition of some shells indicates preservation under high sedimentation rates with low residence time of bioclasts at the sediment/water interface. However, the presence of specimens with splayed shells is usually correlated to the slow decay of the shell ligament in oxygen-deficient bottom waters. The presence of complete carbonized leaves of Glossopteris associated with the bivalve-bearing levels also suggests a possibly dysoxic-anoxic bottom environment. Overall, our data suggest that the bivalves were preserved by abrupt burial, possibly by distal sediment flows into a Brenton Loch lake, and may represent autochthonous to parautochthonous fossil accumulations. The shells resemble those of anthracosiids and are herein assigned to Palaeanodonta sp. aff. P. dubia, a species also found in the Permian succession of the Karoo Basin, South Africa. Our results confirm that (a) the true distributions in space and time of all Permian non-marine (freshwater) bivalves are not yet well known, and (b) there is no evidence for marine conditions in the upper part of the Brenton Loch Formation.  相似文献   
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The National Council for Culture and Arts (NCCA) is the public agency responsible for the implementation of cultural policies in Chile. It was created in 2003 as part of a group of public organisms designed to promote democracy in post-dictatorship Chile, and its objectives include the encouragement of citizen participation in the national culture. This paper aims to call into question the scope and limits of citizen participation in the Chilean cultural field, through a systematisation of paradigms implicitly developed by the NCCA. Those paradigms include participation on the political level, the creation of symbols, recognition of cultural manifestations and access to reception and symbolic appropriation. It identifies challenges of these paradigms regarding representation, recognition, access to creation and reception of cultural manifestations.  相似文献   
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