1,720,994 research outputs found

    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

    Comparison of open and laparoscopic pyeloplasty in ureteropelvic junction obstruction surgery: report of 49 cases.

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    This study aimed to evaluate laparoscopic dismembered pyeloplasty compared with open surgery and to determine whether the morbidity and outcome rates are different in each of these techniques. We report our 10-year experience with open and laparoscopic pyeloplasty at one istitution.From February 1999 to October 2010, 49 patients with ureteropelvic junction obstruction were assigned into two groups. 25 patients underwent open surgical pyeloplasty (period 1999-2010) and 24 underwent laparoscopic pyeloplasty (period 2004-2010). 25 patients undergoing open pyeloplasty had a retroperitoneal flank approach. Of the 24 laparoscopic cases 18 had a transperitoneal retrocolic access, 1 had a transperitoneal transmesocolic access and 5 had a retroperitoneal access. In all 49 cases an Anderson-Hynes dismembered pyeloplasty was used. We retrospectively compared the operative time, hospital stay, perioperative complications and follow-up of the two groups. Clinical symptoms were assessed before and after surgery, subjectively.Patients dermographic data were similar between the two groups with mean age of 42 years (range 6-78) and with a male/female ratio of 1:1.45. A crossing vessel could be identified in 37.5\% (9/24) with laparoscopy vs. 32\% (8/25) in open surgery. Compared with open procedures, laparoscopic procedures were associated with a longer mean operating time (274 vs 143 min), a shorter mean hospital stay (9.9 vs 15.8 day) and the perioperative complication rates were 16.7\% for laparoscopic pyeloplasties and 20\% for open pyeloplasties. The success rates were 90.5\% for laparoscopy and 90.9\% for open surgery. Average follow-up was 40.9 month for the laparoscopic group and 72.3 month for the open group. Failed procedures showed no improvement in loin pain or obstruction.The efficacy (in term of success rate and perioperative complications) of laparoscopic pyeloplasty is comparable to that of open pyeloplasty, with shorter mean hospital stay and better cosmetic results. These findings may suggest, that the laparoscopic dismembered pyeloplasty has the potential to replace open surgery and may be considered the first option for the treatment of ureteropelvic junction obstruction in expert hands

    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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    Communication: Electronic band gaps of semiconducting zig-zag carbon nanotubes from many-body perturbation theory calculations

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    Electronic band gaps for optically allowed transitions are calculated for a series of semiconducting single-walled zig-zag carbon nanotubes of increasing diameter within the many-body perturbation theory GW method. The dependence of the evaluated gaps with respect to tube diameters is then compared with those found from previous experimental data for optical gaps combined with theoretical estimations of exciton binding energies. We find that our GW gaps confirm the behavior inferred from experiment. The relationship between the electronic gap and the diameter extrapolated from the GW values is also in excellent agreement with a direct measurement recently performed through scanning tunneling spectroscopy

    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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