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    Ricerche sulle conseguenze degli stati infiammatori nel periparto. Effetti a livello dell'ingestione di alimenti, delle riserve corporee, della produzione quanti-qualitativa di latte e dell'efficienza alimentare

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    L'ampia letteratura sul periodo di transizione delle bovine richiama sempre più ai rapporti negativi fra problemi di salute e performance delle bovine. Dimostrazioni sempre più numerose confermano l'instaurarsi, soprattutto nel primo mese di lattazione, di una condizione di “stress da malattia”, non sempre associata a manifestazioni cliniche, ma con le stesse conseguenze: i fenomeni infiammatori. I principali obiettivi dei nostri studi, sono stati quelli di meglio caratterizzare gli stati infiammatori puntando l'attenzione su due aspetti: 1°) le cause di variazione della risposta infiammatoria alla infezione microbica e i suoi rapporti con la produzione di latte, 2°) le conseguenze che i fenomeni infiammatori hanno a livello di ingestione degli alimenti, delle riserve corporee, della produzione quanti-qualitativa e quindi dell'efficienza alimentare. relativamente al primo aspetto, nelle bovine sottoposte ad analoga infezione si è osservata una risposta infiammatoria di intensità diversa e che pare in buona relazione con precedenti fenomeni infiammatori in atto o pregressi; inoltre la risposta più intensa ha portato ad un maggior calo produttivo. Le conseguenze sulla efficienza energetica sono state studiate comparando due gruppi di bovine caratterizzate da minori (Lo-lfi) o maggiori (UP-lfi) valori di un indice di funzionalità epatica (lfi). Da ciò è emerso che, nel primo mese di lattazione, specie dopo avvenuta correzione per l'energia mobilizzata delle riserve corporee, l'efficienza è minore nei soggetti con basso lfi per il probabile aumento dei costi del sistema immunitario, aumento che pare prolungarsi ben oltre il fenomeno infiammatorio.The extensive literature on transition period of the cows suggests the growing frequency of negative relationship between health problems and performance. Many evidences confirm during the first month of lactation, the presence of a particular condition named “stress disease”, which is not always associated to clinical symptoms but has the same consequences: the inflammatory processes. The principal objective of this study was to better characterize the inflammatory processes with particular attention to: 1) cause of the changes in inflammatory response to a bacterial infection and its relationship with the milk production, 2) consequences of the inflammatory processes on feed intake, body reserves, quantity and quality of milk production and then on feed efficiency. relatively to the first, we have observed a different intensity of the inflammatory response (in bovine submitted at the same infection), and this response seems correlated to previous inflammatory processes, probably not resolved; moreover, the higher intensity in the inflammations response can be responsible of the milk production decline. The consequences on feed efficiency have been studied through the comparison between two groups of cows characterized by higher (up-lfi) or low (lo-lfi) values of the liver functionality index; from that was demonstrated that during the first month of lactation, the cows with low lfi had lower efficiency values, probably caused increased charge of the immunitary system and prolonged beyond the inflammatory status itself

    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

    Author Index

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