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    Singular curves on K3 surfaces

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    We investigate the Clifford index of singular curves on K3 surfaces by following the lines of [10]. As a consequence, we are able to deduce from [3] that Green’s conjecture holds for all integral curves on K3 surfaces

    Linear systems on weak del Pezzo surfaces

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    We investigate the gonality and the Clifford index of smooth curves on weak Del Pezzo surfaces by following the lines of [12]

    Aplasia cutis congenita in surviving co-twins: four unrelated cases

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    Four unrelated patients born from twin pregnancies and showing extracranial aplasia cutis congenita are reported. All the patients lost their co-twins during the first half of the pregnancy. Two of the patients had the characteristic truncal and symmetrical type of aplasia cutis associated with fetus papyraceus and placental abnormalities. The presence of multiple hepatic hematomas in one of them gives further credit to a "vascular disruption" as the possible pathogenetic mechanism of the disorder. The two other patients were born with symmetrical aplasia cutis at the extensory aspects of both knees, which presumably represents a milder expression of the former defect. Thus the so-called aplasia cutis with fetus papyraceus shows heterogeneity in localization, extension, presence of extracutaneous abnormalities, and possible association with fetus papyraceus at birth. To include all the patients affected by this peculiar type of aplasia cutis congenita, the designation of aplasia cutis with extracranial symmetrical involvement is proposed

    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

    Risk factors for cutaneous malignant melanoma in a northern Italian population

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    The relationship between cutaneous malignant melanoma (CMM) and the colour of skin, hair and eyes, the extent of sun exposure and reaction to it, education, and the occurrence of skin neoplasms in patients and their families was evaluated in a case-control study of 103 cases of CMM and 205 control subjects hospitalized for acute conditions other than malignant or hormonal disease. A significantly higher risk was associated with fair skin as compared to dark/medium skin (RR = 4.0; 95% CI: 1.5-10.5) and positive family history for CMM (RR = 8.1; 95% CI: 1.0-200.9). CMM seemed to occur more frequently, but not significantly so, in individuals with brown or blond hair, higher education and clinically diagnosed dysplastic naevi. Outdoor occupation and heavy sun exposure in the last 20 years seemed to increase the risk of CMM in sun-exposed sites but to be negatively associated with CMM in normally unexposed sites

    Author Index

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