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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
A theoretical dose-escalation study based on biological effective dose in radioimmunotherapy with (90)Y-ibritumomab tiuxetan (Zevalin)
No full textAim To investigate the variation in biological effective dose (BED) produced by the uncertainty in absorbed dose and radiobiological parameters in Zevalin radioimmunotherapy. Methods Eight patients scheduled for treatment with standard administration of 90Y-ibritumomab tiuxetan (Zevalin) were studied. Patient-specific pretherapy dosimetry was performed by injection of 111In-ibritumomab tiuxetan. Absorbed doses and BEDs were calculated for critical organs (COs) and tumours, assuming a 30% dose uncertainty and varying the radiobiological parameters in a reasonable range. In an activity-escalation study, BEDs for the COs were compared with the BED limits of external beam radiotherapy (EBRT) and BEDs for the tumour with the EBRT dose prescriptions. Results At standard activities, the absorbed doses per unit activity for the COs were in agreement with those in the literature. Absorbed doses to lesions were rather variable, ranging from 1.47 to 16.7 Gy/GBq. Median tumour absorbed dose to lesions in the range 80–110 g was 9.6 Gy/GBq (range 9.2–16.7 Gy/GBq), yielding a mean BED of about 12 Gy for administration of 15 MBq/kg. For the administration of the myeloablative activity of 45 MBq/kg, risk of liver toxicity in one patient would have been foreseen by the model. Considering also the dose uncertainty, the potential risk of liver toxicity in one more patient, lung toxicity in one patient, and kidney toxicity in one patient would have been suggested. The absorbed dose uncertainty was found to be the main source of uncertainty in the BED. As for radiobiological parameters, at myeloablative activities, the increase in the repair half-time for sublethally damaged tissue (T?) from 0.5 h to 5 h induced more consistent increases in mean BED/BEDlimit than ?/? variation from 2 Gy to 5 Gy: at 53 MBq/kg, 38% for the liver, and 34% for the lungs and kidneys (about threefold higher than that obtained for the increase ?/?). Conclusion At standard activities, absorbed doses to lesions appear to be effective, even though lower than prescribed by EBRT. At myeloablative dosages, the uncertainty associated with the absorbed doses and radiobiological parameters considerably affect BED evaluation and may account for possible “second-organ” toxicities
123I ioflupane SPECT correlates with Dopamine trasporter in peripheral mononuclear cells.
No full textDetection of recurrence of colorectal adenocarcinoma with 18-F-FDG PET-CT in patients with negative markers.
No full textRelationship between123I ioflupane SPECT and expression of DAT in peripheral mononuclear cells.
No full textUse of 99m-Technetium labelled rituximab for imaging of patients with chronic inflammatory diseases
No full textVariations 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
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