1,720,964 research outputs found
In Regard to Kubicek et al.
We read the article “Stereotactic radiosurgery
for poor performance status patients” by Kubicek
et al recently published in your journal.
The authors concluded that patients with poor performance
status (PS) could be ideal candidates for stereotactic
radiosurgery (SRS), given the favorable logistics of singlefraction
treatment and a potential survival advantage. From
our point of view, however, further consideration needs to
be given regarding the use of these technologies in poor PS
patients
Bone structure texture analysis as a potential tool to estimate radiation induced insufficiency fracture risk.
the possible role of bone structure TA(texuture analysis as a potential tool to estimate radiation induced insufficiency fracture risk, but further prospective studies on a large population are needed to best estimate the actual
preliminary data
The combined EGFR protein expression analysis refines the prognostic value of the MGMT promoter methylation status in glioblastoma.
Background/aims To investigate the combined prognostic value of the EGFR expression level and the MGMT promoter methylation status in Glioblastoma (GB). Methods We assessed the EGFR protein expression level by immune-histochemical (IHC) evaluation and the MGMT promoter methylation status by Polymerase Chain Reaction (PCR) in 169 patients affected by GB. We assessed the prognostic significance of combined MGMT methylation status and EGFR expression level in terms of Overall Survival (OS) with univariate and multivariate analysis, and validated this finding using an external data set of GB patient. Results Clustering survival analysis for the methylation status of MGMT (methMGMT/unmethMGMT) and EGFR expression (High EGFR: H-EGFR; Low EGFR: L-EGFR), identified three different prognostic groups (p = 0.001), as follows. Patients with unmethMGMT/H-EGFR had the shortest survival time (median OS: 5 months) and patients co-expressing methMGMT/L-EGFR had the best prognosis (median OS: 35 months), as compared to the other two sub-groups (methMGMT/H-EGFR; unmethMGMT/L-EGFR), which had respectively median OSs of 11 and 12 months. The combined MGMT methylation and EGFR amplification status analysis showed a similar prognostic impact in an independent series, which we used for validation (p = 0.001). Conclusions The EGFR expression evaluation refines the prognostic value of MGMT methylation status in GBs
Going Beyond Counting First Authors in Author Co-citation Analysis
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
“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
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
Dispelling the Myths Behind First-author Citation Counts
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
- …
