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    NIV in the acute setting: technical aspects, initiation, monitoring, and choice of interface

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    Noninvasive ventilation (NIV) reduces the work of breathing, improves gas exchange and may improve clinical outcome in patients with acute respiratory failure (ARF) of various origin. Failure of NIV occurs, however, in y20 30% of patients with hypercapnic ARF and in an even higher percentage of patients with hypoxaemic ARF. NIV failure may be due to clinical or technical factors such as the ventilatory mode and settings. Poor adaptation to the interface may also be responsible for some cases of NIV failure. It is therefore important to take into account these technical aspects in order to increase the efficacy of NIV. Both home and intensive care unit ventilators have been used to delivered NIV but the latter are preferred in the most severe critically ill patients. Three main types of interfaces are currently available in acute situation: facial, nasal and the helmet. The facial mask is generally considered the first choice in terms of efficacy. The helmet is an acceptable alternative to deliver continuous positive airway pressure in selected patients with hypoxaemic ARF. The most rational approach is, however, to adapt the type and the size of the interface on an individual basis. Humidification of inspired gas, often considered of minor relevance, is important to improve patient s comfort. In spite of a theoretical superiority of heated humidifiers over heat and moisture exchangers, particularly in patients with hypercapnic ARF, no study has yet confirmed it to date. Finally, adequate patient selection, preparation and monitoring are crucial in making NIV successful

    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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