1,721,116 research outputs found
Going Beyond Counting First Authors in Author Co-citation Analysis
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
“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
EFFECTS OF TWO DIFFERENT FRACTIONS OF INSPIRED OXYGEN ON LUNG AERATION AND GAS EXCHANGE IN CATS UNDER INHALANT ANAESTHESIA
Objective To compare the effects of two fractions of inspired oxygen (FiO 2) (0.4 and 1) on lung aeration and gas exchange during general anaesthesia in cats.Study design Randomized, blinded, controlled study.Animals Thirty healthy, mixed breed, client owned female cats.Materials and methods Cats were premedicated intramuscularly with acepromazine (0.03 mg kg -1) and medetomidine (0.015 mg kg -1). Anaesthesia was induced with propofol (5 mg kg -1) and, after orotracheal intubation, maintained with isoflurane carried by either 100% oxygen (G100, n = 15) or an oxygen-air mixture with 40% oxygen (G40, n = 15). All cats were placed in dorsal recumbency and breathed spontaneously throughout the entire procedure. Following surgery (ovariectomy), a spiral computed tomography (CT) of the thorax was performed, arterial oxygen (PaO 2) and carbon dioxide (PaCO 2) tensions were measured and alveolar-arterial gradient of oxygen [P(A-a)O 2] calculated. The CT images were analysed for lung aeration by the analysis of radiograph attenuations (Hounsfield units, HU), according to the following classification: hyperinflated area (-1000 to -900 HU), normally aerated area (-900 to -500 HU), poorly aerated area (-500 to -100 HU) and non-aerated area (-100 to +100 HU). The groups were compared using one-way anova.Results Compared to G100, the normally-aerated lung area was significantly greater and the poorly-aerated and non-aerated areas were significantly smaller in G40. PaCO 2 was similar in both groups. PaO 2 and P(A-a)O 2 were significantly higher in G100. In both groups, pulmonary atelectasis developed preferentially in the caudal lung fields.Conclusion In cats anaesthetised with isoflurane, the administration of an FiO 2 of >0.9 significantly impaired lung aeration and gas exchange as compared to an FiO 2 of 0.4.Clinical relevance An FiO 2 of 0.4 may better preserve lung aeration and gas exchange in anaesthetised spontaneously breathing cats but monitoring is essential to ensure oxygenation is adequat
Appropriate Similarity Measures for Author Cocitation Analysis
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
Integrazione linguistica e immigrazione: luci e ombre del sistema italiano nel contesto dell’Unione europea
Dispelling the Myths Behind First-author Citation Counts
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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