1,721,014 research outputs found
Problemi dosimetrici
No full textAnalisi dei problemi correlati alla esposizione a radiazioni ionizzanti a seguito di esami TC su apparecchiature multislice.
Modalità per ridurre la dose radiante
Ground-glass opacity: Interpretation of high resolution CT findings
No full textGround-glass opacity (GGO) is a common finding on high resolution CT, characterized by areas of hazy increased attenuation of the lung with preservation of bronchial and vascular margins; it is not to be confused with consolidation, in which bronchovascular structures are obscured. It correlates with several pathogenic processes, such as like partial filling of air spaces, inflammatory or fibrotic interstitial thickening, increased capillary blood volume. Infiltrative GGO can representing either interstitial or alveolar processes. GGO is a nonspecific finding; however, the correlation with any of the associated CT findings (nodular lesions, consolidation, septal thickening, fibrosis, vessels or airway calibre alterations, air trapping), and clinical data is helpful in narrowing the range of diagnostic possibilities, or even in suggesting a specific diagnosis. GGO can indicate a potentially treatable disease, help guide the type and location of biopsy and evaluate the effectiveness of therapy. This review discusses the types of lung disease associated with GGO, and the differential diagnosis between GGO caused by infiltrative processes and the mosaic patterns of lung attenuation caused by primary vascular diseases or airway abnormalities. This distinction can be made by evaluating the vessel calibre and air trapping on expiratory scans
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
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