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    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

    ADENYLYL CYCLASE ACTIVITY AND ITS MODULATION IN GILLS OF Mytilus galloprovincialis EXPOSED TO HEAVY METALS.

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    The adenylyl cyclase (AC)/cAMP system regulates a large number of physiological functions in bivalve mussels, although its basal properties and the potential effects of environmental pollutants are scarcely studied. We characterized some properties of AC and measured both the enzyme activity and the cAMP levels in the gills of the filter-feeding sea mussel Mytilus galloprovincialis. Basal AC activity was 5.6+/-0.8 pmol cAMP 10 min(-1) mg protein(-1) and showed a Km value of 0.82+/-0.06 mM for ATP in the presence of 5mM Mg2+. It was stimulated up to 2.5- and 3.5-fold by 5-HT and GTPgammaS, respectively. Similarly to what was found in other bivalves, forskolin is a poor activator that reached significant stimulation only at 100 microM. Both basal and 5-HT-stimulated AC activity were significantly increased in the gills of mussels exposed for 7 days in aquaria to Cr6+ (10 ng/l) and Cu2+ (5 microg/l). The cAMP content of the gill under these conditions was also significantly higher than in control animals. In vitro exposure of gill membrane preparations to Cr6+ and Cu2+ induced a bimodal effect. Cu2+ significantly stimulated AC activity at nanomolar concentrations, but a strong inhibition was displayed in the micromolar range. A similar bell-shaped curve was obtained in the presence of Cr6+, with maximal AC stimulation at 10(-8)M and inhibition at 10(-5)M. Overall, these data suggest that the mussel AC/cAMP system can be affected with different patterns by heavy metals. AC activity is strongly affected by acute exposure to heavy metals in vitro, probably through a direct interaction of the pollutants with the enzyme molecule, while AC activity and cAMP content increase in organisms exposed for 7 days in vivo, probably as a defense response to acclimate the physiological functions to the environmental challenge

    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

    Modulation of adenyl cyclase activity in the gills of Tapes philippinarum.

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    Adenyl cyclase (AC) plays a pivotal role in cell signaling. The AC system of bivalves has received little attention so far, and our study has been addressed to the characterization of AC properties in the gills of T. philippinarum. The enzyme showed a Km value of 0.77 mM for ATP in the presence of 5 mM Mg2+; in the absence of agonists, it was poorly affected by GTP, while it was stimulated by GTPgammaS and GppNHp up to 14-fold and 4-fold, respectively. Similarly to other invertebrates, the enzyme activity was scarcely stimulated by forskolin. The receptor agonist serotonin (5-HT) significantly stimulated the AC activity, and the pharmacological profile of the 5-HT receptor/s was as follows: (+)butaclamol > dihydroergocryptine > methysergide > prazosin > yohimbine. The AC activity was assessed in vitro in the presence of tributyltin chloride and HgCl2, which reduced the AC activity only at the highest dose tested (10-100 microM). Our data indicate the presence of a membrane-bound AC in gill membranes of T. philippinarum, coupled to Gs proteins and to a specific class of 5-HT receptors. Such receptors show a pharmacological profile slightly different from that reported for 5-HT invertebrate receptors cloned so far

    Trauma complesso dell'arto inferiore con lesione completa del tendine rotuleo e perdita di sostanza

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    Presentiamo il caso di un giovane di 25 anni che, in seguito ad un incidente motociclistico ha riportato un trauma complesso dell'arto inferiore con plurime fratture esposte (tibia, femore, rotula) Gustilo III B e lesione del tendine rotuleo con perdita di sostanza. Il Paziente è statao trattato in urgenza con toilette e debridement conservativo dei tessuti e stabilizzazione temporanea con fissatore esterno a ponte. In un secondo tempo si è proceduto a stabilizzazione definitiva con FEA, sintesi dei condili femorali e del piatto tibiale con viti cannulate e reiserzione del tendine rotuleo con ancorette. In associazione è stato eseguito intervento di chirurgia plastica. A distanza di sei mesi è stato rimosso il FE e al controllo clinico l'estensione del ginocchio è completa
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