1,721,983 research outputs found
Testis biopsy for infertility: A comparative assessment of current score methods for the evaluation of the histological specimen.
No full textCorrelation between angiographic success and functional improvement assessed by exercise test following percutaneous transluminal coronary angioplasty.
No full textCorrelation between angiographic success and functional improvement assessed by exercise test following percutaneous transluminal coronary angioplasty.
Barillà F, Romeo F, Tomai F, Pace V, Valente A, Martuscelli E, Nigri A, Reale A.
Source
2nd Department of Cardiovascular Diseases, University La Sapienza, Rome, Italy.
Abstract
Sixty-one consecutive patients with stable effort angina and single vessel disease underwent successful (reduction of coronary stenoses by greater than or equal to 20%) percutaneous transluminal coronary angioplasty (PTCA). Anatomical results were analysed on the basis of functional evaluation obtained by exercise test (ET) 1 week before (pre-PTCA) and within 1 month after (post-PTCA) PTCA. Total exercise duration and maximal double product significantly increased after PTCA (4.5 +/- 1 min vs 6.9 +/- 1.5 min, p less than 0.001 and 14.1 +/- 3.6 x 1000 mmHg x bpm vs 18 +/- 4.2 x 1000 mmHg x bpm, p less than 0.001). Pre-PTCA ET was positive in 43 patients (70%) and post-PTCA ET in 15 (24%). In patients with post-PTCA positive ET, mean stenosis diameter reduction was significantly lower than that obtained in patients with negative post-PTCA ET (29.6 +/- 8.9% vs 61.1 +/- 18.8%, p less than 0.001). In conclusion, PTCA improved exercise tolerance in the majority of patients with myocardial ischemia, however the definition of anatomical success used in this study appears to be poorly correlated with functional improvement as assessed by ET
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
Thermal model of high-power amplifiers based on time-dependent temperature profiles measured by photoconductance
No full textWe developed a theoretical model to fully describe the time-dependent thermal behavior of high-power amplifiers (HPA), considering all the main thermal resistances related to the junction/chip/package/heat sink interfaces. We also included thermal capacitances to fully describe transient behavior of time-dependent temperature profiles. Our thermal model allows the extraction of thermal resistance and thermal capacitance from observable variables, related to the time constants of experimentally measured temperature profiles, extracted in pulsed regime corresponding to different C- And X-band HPA based on GaAs and GaN technologies. Temperature profiles are extracted from time resolved photoconductance spectroscopy
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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