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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

    The “PAC-MAN” sign: an insidious complication after transcatheter aortic valve deployment

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    Transcatheter aortic valve implantation (TAVI) is now a viable and effective alternative to conventional surgical aortic valve replacement for high-risk patients with severe aortic stenosis. Despite its percutaneous and less invasive nature, TAVI is associated with the potential for several intraprocedural complications, which have been recently updated and standardized. Some of them, such as those relating to valve deployment and/or positioning, occur less frequently but they could however represent very serious and life-threatening complications. We report the case of an insidious TAVI complication that required a combined fluoroscopic/echocardiographic approach in order to allow a correct deployment of the transcatheter prosthesis. Our case report highlights this potentially specific under-deployment of large CoreValve prosthesis. Medico-surgical community involved in TAVI must be nowaware of this newtype of complication allowing its successful management

    Total percutaneous femoral vessels cannulation for minimally invasive mitral valve surgery

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    BACKGROUND: Minimally invasive mitral valve surgery (MIMVS) has experienced several technological changes in the last two decades. Our aim was to describe one of the most recent improvements, the utilization of a total percutaneous femoral vessels cannulation technique during MIMVS. METHODS: We performed a retrospective observational analysis of this technique among 300 consecutive MIMVS patients, with particular focus on cannulation aspects of MIMVS, its success rate and potential complications. RESULTS: From October 2008 to December 2012, 300 patients (60% males) were operated on. Mean age was 62.9±16.4 years. Indications for operation included mitral valve repair (93%) and mitral valve replacement (7%). Two femoral arterial catheterizations failed and required conversion to sternotomy. The complications on the arterial side were: 5 (1.6%) cases of bleeding during the introduction of Prostar leading to a preoperative surgical hemostasis; 2 (0.6%) retroperitoneal bleeds during cardiopulmonary bypass requiring difficult surgical control but with an uneventful follow-up; 6 (2%) bleeding episodes after removal of the arterial cannula easily controlled by direct surgical revision; 1 (0.3%) arterio-venous fistula requiring a surgical correction on postoperative day 32; 1 (0.3%) patient had a transitory claudication due to a superficial femoral artery thrombosis progressively compensated by the collateral circulation. There were no postoperative bleeding complications. There were no other complications linked to the femoral cannulations or to the groin occurred during the follow-up. The percentage of uneventful arterial cannulations was 80% among the first 50 patients (N=10 out of 50) and 98.8% thereafter (N=3 out of 250). CONCLUSIONS: Total percutaneous femoral vessels cannulation technique is particularly suitable for MIMVS with a high success rate and few complications after a short learning curve. With the advent of the percutaneous approach, the traditional complications of the groin incision have completely disappeared in modern operations with no groin infection, hematoma or lymphocele

    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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    koamabayili/VECTRON-author-checklist: VECTRON author checklist

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    We have done our best to complete the author checklist relating to the use of animals in the hut study. Note that the objective for the hut study was to evaluate the IRS treatment applications for residual efficacy against Anopheles mosquitoes, including the local An. coluzzii mosquito population. Cows were only used to attract mosquitoes into the huts and no tests were carried out directly on the cows. The author checklist is intended for use with studies where experiments are carried out on animals, which is why we have had such difficulty in completing this for the hut study, as many of the questions do not relate to how the cows were used
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