1,721,149 research outputs found

    Life and ideas of Giovanni Capellini (1833–1922): a palaeontological revolution in Italy

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    During the nineteenth century Europe and then America were the focal points for major advances in the study of palaeontology and the great, often acrimonious, debate on evolutionary theory. Natural history was one of the great educational disciplines of the day and those involved were part of an educated elite who practised as medics, clergymen, chemists and anatomists. Some were shy and retiring, others forceful even bombastic, sometimes evil by intent. Many were driven by fame and it was their wish to discover the best, the biggest and the most important specimens they could get their hands on. Others were great orators who could defend a cause; some were the first of many who became diligent and careful in the collection and storage of material or brilliant field scientists who taught us the importance of observation, data gathering and interpretation of sedimentary successions worldwide. Being considered worthy of joining such an elite social, scientific circle was an immense tribute to their contribution to the natural sciences. It was an honour denied William Smith who lacked the educational background of the middle classes of the time, but given in abundance to the Italian scientist Giovanni Capellini who was born into an upper middle-class Italian family and who received a classic ecclesiastical training before venturing into the natural sciences. © The Geological Society of London 2010

    The "Continental Intercalaire" of southern Tunisia: Stratigraphy, paleontology, and paleoecology

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    The "Continental Intercalaire" deposits of southern Tunisia preserve one of the most diverse Early Cretaceous vertebrate fauna from Africa, consisting of elasmobranchs, actinopterygians, sarcopterygians, turtles, crocodyliforms, pterosaurs, and non-avian dinosaurs. Vertebrate remains representative of both marine and fluvial environments have been historically referred to a specific bonebed within the Chenini Member, which crops out extensively in the Tataouine region. A stratigraphic revision of the mainly siliciclastic deposits of the Douiret and the Aïn El Guettar formations in the area based on new sedimentological and paleontological data is presented. Data collected indicate the presence of multiple fossil-bearing strata encompassing the stratigraphic interval from the Berriasian to the Albian and document faunal variation through time as well as major environmental and climatic changes. Detailed sedimentological analysis combined with biostratigraphic correlation performed at a basin scale indicate lateral facies variability within each formation as a result of tectonically and climatically driven zonations within the Tataouine Basin in the Early Cretaceous. Furthermore, proposed stratigraphic correlations indicate that vertebrate remains previously referred to the fluvial Chenini Member (and in particular theropod and sauropod dinosaurs) are instead representative of a transgressive deposit which mark the base of the overlying Oum ed Diab Member. © 2012 Elsevier Ltd

    Theropod tooth assemblages from the Late Cretaceous Maevarano Formation and the possible presence of dromaeosaurids in Madagascar

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    Over 180 isolated theropod teeth recovered from the Maevarano Formation (Campanian?-Maastrichtian) of the Mahajanga Basin were studied in order to document theropod diversity in the Malagasy insular setting. Tooth morphology and characteristics of the Maevarano teeth were compared to those of known theropod teeth for identification, including the Malagasy non-avian theropods Majungatholus atopus and Masiakasaurus knopfleri. Tooth and denticle morphologies permit the recognition of five tooth morphotypes: three are referable to Majungatholus atopus and one to Masiakasaurus knopfleri. Statistical analyses reveal that the fifth morphotype is similar to dromaeosaurid teeth, suggesting that a yet unknown theropod taxon inhabited Madagascar during the Late Cretaceous. This morphotype support the theory that dromaeosaurids were present throughout Pangea before the break-up of the supercontinent during the Late Jurassic and had colonized Madagascar before its separation from Africa during the Early Cretaceous

    Going Beyond Counting First Authors in Author Co-citation Analysis

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    The present study examines one of the fundamental aspects of author co-citation analysis (ACA) - the way co-citation counts are defined. Co-citation counting provides the data on which all subsequent statistical analyses and mappings are based, and we compare ACA results based on two different types of co-citation counting - the traditional type that only counts the first one among a cited work's authors on the one hand and a non-traditional type that takes into account the first 5 authors of a cited work on the other hand. Results indicate that the picture produced through this non-traditional author co-citation counting contains more coherent author groups and is therefore considerably clearer. However, this picture represents fewer specialties in the research field being studied than that produced through the traditional first-author co-citation counting when the same number of top-ranked authors is selected and analyzed. Reasons for these effects are discussed

    Variations on the Author

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    “Variations on the Author” discusses two of Eduardo Coutinho’s recent films (Um Dia na Vida, from 2010, and Últimas Conversas, posthumously released in 2015) and their contribution to the general question of documentary authorship. The director’s filmography is characterized by a consistent yet self-effacing form of authorial self-inscription: Coutinho often features as an interviewer that rather than express opinions propels discourses; an interviewer that is good at listening. This mode of self-inscription characterizes him as an author who is not expressive but who is nonetheless markedly present on the screen. In Um Dia na Vida, however, Coutinho is completely absent form the image, while Últimas Conversas, on the contrary, includes a confessional prologue that moves the director from the margins to the center of his films. This article examines the ways in which these works stand out in the filmography of a director who offers new insights into the notion of cinematic authorship
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