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    Can liquefied debris flows deposit clean sand over large areas of sea floor? Field evidence from the Marnoso-arenacea Formation, Italian Apennines

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    The Marnoso-arenacea Formation in the Italian Apennines is the only ancient rock sequence where individual submarine sediment density flow deposits have been mapped out in detail for over 100 km. Bed correlations provide new insight into how submarine flows deposit sand, because bed architecture and sandstone shape provide an independent test of depositional process models. This test is important because it can be difficult or impossible to infer depositional process unambiguously from characteristics seen at just one outcrop, especially for massive clean-sandstone intervals whose origin has been controversial. Beds have three different types of geometries (facies tracts) in downflow oriented transects. Facies tracts 1 and 2 contain clean graded and ungraded massive sandstone deposited incrementally by turbidity currents, and these intervals taper relatively gradually downflow. Mud-rich sand deposited by cohesive debris flow occurs in the distal part of Facies tract 2. Facies tract 3 contains clean sandstone with a distinctive swirly fabric formed by patches of coarser and better-sorted grains that most likely records pervasive liquefaction. This type of clean sandstone can extend for up to 30 km before pinching out relatively abruptly. This abrupt pinch out suggests that this clean sand was deposited by debris flow. In some beds there are downflow transitions from turbidite sandstone into clean debrite sandstone, suggesting that debris flows formed by transformation from high-density turbidity currents. However, outsize clasts in one particular debrite are too large and dense to have been carried by an initial turbidity current, suggesting that this debris flow ran out for at least 15 km. Field data indicate that liquefied debris flows can sometimes deposit clean sand over large (10 to 30 km) expanses of sea floor, and that these clean debrite sand layers can terminate abruptly

    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

    Appropriate Similarity Measures for Author Cocitation Analysis

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    We provide a number of new insights into the methodological discussion about author cocitation analysis. We first argue that the use of the Pearson correlation for measuring the similarity between authors’ cocitation profiles is not very satisfactory. We then discuss what kind of similarity measures may be used as an alternative to the Pearson correlation. We consider three similarity measures in particular. One is the well-known cosine. The other two similarity measures have not been used before in the bibliometric literature. Finally, we show by means of an example that our findings have a high practical relevance.information science;Pearson correlation;cosine;similarity measure;author cocitation analysis

    Dispelling the Myths Behind First-author Citation Counts

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    We conducted a full-scale evaluative citation analysis study of scholars in the XML research field to explore just how different from each other author rankings resulting from different citation counting methods actually are, and to demonstrate the capability of emerging data and tools on the Web in supporting more realistic citation counting methods. Our results contest some common arguments for the continued use of first-author citation counts in the evaluation of scholars, such as high correlations between author rankings by first-author citation counts and other citation counting methods, and high costs of using more realistic citation counting methods that are not well-supported by the ISI databases. It is argued that increasingly available digital full text research papers make it possible for citation analysis studies to go beyond what the ISI databases have directly supported and to employ more sophisticated methods

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