1,721,194 research outputs found
Going Beyond Counting First Authors in Author Co-citation Analysis
Full text linkThe 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 linkWe 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
Digital videomicroscopy improves diagnostic accuracy for melanoma
No full textBackground: To enhance the clinical evaluation of pigmented skin lesions (PSL), examination of PSL at a high magnification and computer-aided diagnosis have been introduced. Besides surface microscopes, videomicroscopes that are provided with polarized light are commercially available. Images recorded in the polarizing mode are comparable with those obtained after application of a drop of oil and a glass slide. Objective: The purpose of this study was to evaluate the usefulness of a digital videomicroscope equipped with a dedicated program for the diagnosis of melanocytic PSL by assessing the digital features referring to benign and malignant PSL images and by comparing the clinical assessment performed on 20-fold magnified images to computer diagnosis that were provided by the discriminant analysis calculation carried out on the numeric values describing the images. Methods: Nine hundred seventeen melanocytic PSL images, corresponding to 852 nevi and 65 melanomas, were considered. For microscopic examination, a 10- (39 cases), 20-(501 cases), or 50-fold magnification (377 cases) was chosen according to the size of the lesion, enabling the whole lesion to be seen on the monitor. All digital images were framed and analyzed with software that calculates different features related to the geometry, color distribution, and internal pattern of the lesion. Features referring to benign and malignant PSL were compared. Moreover, 90 PSL images recorded by a x20 magnification, corresponding to 59 benign PSL and 31 malignant melanomas, were evaluated by 2 observers, 1 observer experienced in videomicroscopy and 1 observer, an untrained dermatologist, Sensitivity and specificity were estimated for observer assessment and computer diagnosis. Results: Significant differences between values referring to benign and malignant PSL were observed for most numeric features. Sensitivity was higher for the computer assessment and lower for the inexperienced observer, whereas specificity was the same for the computer and the trained observer. Conclusion: Numeric features referring to benign PSL significantly differ from those of malignant PSL images. Elaboration of videomicroscopic images by means of a dedicated program improves diagnostic accuracy over the simple examination of pigmented skin lesions by means of magnifying and polarizing systems
Sodium Hydroxide-Induced Irritant Dermatitis As Assessed By Computerized Elaboration Of 20-Mhz B-Scan Images And By Tewl Measurement - A Method For Investigating Skin Barrier Function
No full textSodium hydroxide-induced irritation was studied in 34 volunteers, by means of 24-h patch testing at different concentrations, and by a 10-min testing procedure employing 0.1 mol/l NaOH. As a supplement to subjective evaluation of skin changes, assessments of test areas by TEWL measurement and sonography were performed at 24, 48 and 72 h. After 24-h patch testing, instrumental evaluations showed an increase in the extension of the hypo-echogenic dermal area and in TEWL, whereas a 10-min NaOH application induced a decrease of the dermal and epidermal reflectivity and an increase in TEWL. Twenty-four hour patch testing with 4% NaOH allowed a classification of subjects into two categories: subjects who reacted normally and hyper-reactors. Hyper-reactors showed an enhanced inflammatory response and a more pronounced barrier function damage, as assessed clinically and instrumentally by decreased dermal reflectivity, and by higher postexposure TEWL. Subjects with a more marked inflammatory response to 4% NaOH also showed greater TEWL increases during the short-term testing procedure employing 0.1 mol/l NaOH. Moreover, these subjects were characterized by higher baseline TEWL values, indicating that cutaneous reactivity to NaOH is at least partly correlated to impaired stratum corneum function, which is inadequate to effectively prevent compounds from penetrating the skin
DOUBLE STACKED SUPERCONDUCTING JUNCTIONS FOR INVESTIGATING THE PROXIMITY EFFECT IN NB/AL BILAYERS
No full textDispelling the Myths Behind First-author Citation Counts
Full text linkWe 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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