1,721,069 research outputs found

    Going Beyond Counting First Authors in Author Co-citation Analysis

    Full text link
    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

    Full text link
    “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

    Full text link
    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

    Extracorporeal venovenous membrane oxygenation in the treatment of respiratory insufficiency following cardiac surgery

    No full text
    Following cardiac surgery, patients can develop acute respiratory failure. We present the case of a 66-year-old male successfully treated with extracorporeal venovenous membrane oxygenation (vvECMO) for acute respiratory failure postsurgery and review the literature on vvECMO in this specific setting. doi: 10.1111/jocs.12278 (J Card Surg 2014;29:270-273) © 2014 Wiley Periodicals, Inc

    Transesophageal Echocardiography For The Assessment of Left Atrial Pressure After Trans-Septal Mitral Valve Interventions

    No full text
    : The measure of left atrial pressure (LAP) is an ideal marker for the clinical efficacy of transcatheter mitral valve intervention. Currently, only the invasive measurement of LAP (i-LAP) is available and no echocardiographic methods are reliable in the setting of transcatheter mitral valve intervention. This study sought to validate a new echocardiographic method for the estimation of LAP (e-LAP) by comparing it with i-LAP. During percutaneous edge-to-edge procedure with MitraClip, the i-LAP was routinely monitored. Across the iatrogenic interatrial septum defect, the flow was sampled with continuous-wave Doppler echocardiography for deriving the mean pressure gradient between the left atrium and the right atrium, and the central venous pressure was added to obtain the e-LAP. The correlation between the measures derived from these 2 methods was explored. A total of 34 consecutive patients were included. Intraclass correlation coefficient between e-LAP and i-LAP was high (intraclass correlation coefficient [95% confidence interval] 0.809 [0.625 to 0.902], R Pearson 0.6, p <0.001); a bias of -1.3 mm Hg for e-LAP versus i-LAP was found (p = 0.32). The median follow-up was 108 days (interquartile range 40 to 264). No death occurred and 6 patients were rehospitalized for heart failure. Postimplant e-LAP was correlated with rehospitalization at follow-up (hazard ratio 1.46, 95% confidence interval 1.022 to 2.1, p = 0.038). A cut-off value of 9.5 mm Hg for the e-LAP was identified as predictor of rehospitalization for heart failure. The evaluation of e-LAP has optimal reliability compared with i-LAP; a value more than 9.5 mm Hg was found to be related to higher risk of events at short follow-up

    Results of tricuspid valve surgery for functional tricuspid regurgitation: acute and long-term outcomes and predictors of failure

    No full text
    The assessment and management of tricuspid valve disease evolved significantly in the last decade. Tricuspid regurgitation is a frequent heart valve disease and it is most often secondary, due to annular dilatation and leaflet tethering from right ventricular remodelling. The indications for tricuspid valve surgery are several and mainly related to the underlying disease, to the severity of the regurgitation and to the right ventricular function. Moreover, surgical tricuspid repair has been avoided for years, because of the erroneous concept that tricuspid regurgitation should disappear once the primary pathology on the left heart has been resolved. Instead, during the last few years, many investigators have reported evidence in favour of a more aggressive surgical approach to functional tricuspid regurgitation, recognising the risk of progressive tricuspid insufficiency in patients with annular dilatation and only moderate regurgitation (or less) at the time of surgery. This concept, along with the acute and long-term outcomes of tricuspid surgical repair techniques and tricuspid replacement are discussed in this review

    Dispelling the Myths Behind First-author Citation Counts

    Full text link
    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
    corecore