1,720,972 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
CT myocardial perfusion. State of the science
No full textNon-invasive cardiac imaging has rapidly evolved during the last decade due to advancements in CT technologies. Coronary CT angiography (CCTA) has been shown to reliably assess the coronary anatomy and has established itself as the non-invasive imaging technique with the highest sensitivity and specificity in the evaluation of patients with suspected coronary artery disease (CAD). However, this technique has previously been limited to a pure anatomical assessment. CT myocardial perfusion imaging (CT-MPI) is an increasingly rediscovered CT technique able to provide functional assessment of the myocardium and, when combined with CTA, allows for a comprehensive assessment of the coronary arteries, all done within a single modality. This review will describe the current knowledge in CT-MPI, including the varying techniques as well as a summary of the current literature
The Challenging Patient
No full textIn the past decade, coronary CT angiography (CCTA) has established itself as a robust imaging technique for the exclusion of coronary artery disease (CAD) in patients presenting with acute chest pain and moderate cardiovascular risk due to its high sensitivity and negative predictive value in detecting significant coronary artery stenosis. Noninvasive CCTA has become a reliable alternative to inva- sive angiography and, thanks to recent technical innova- tions, has raised its power from just a morphological evaluation to a more comprehensive morphological and functional assessment. Specifically, novel CT technological advancements such as CT myocardial perfusion imaging (CT-MPI) provide a reliable functional analysis of the heart capable of accurately presenting hemodynamically significant coronary artery stenosis. CCTA coupled with CT-MPI could raise CT as the stand-alone image modality for a com-prehensive evaluation of CAD and direct assessment of myo- cardial ischemia in a single examination.
Technically speaking, CCTA presents a greater challenge and is more demanding than other CT applications due to the nature of its target, the continuously moving heart. Thus, higher spatial and temporal resolutions are mandatory for a proper visualization of small-caliber vessels such as cor- onary arteries. In addition, image acquisition should be syn- chronized with the patient’s electrocardiogram (ECG) in order to achieve optimal image quality. Due to its technical com- plexity, the accurate selection and preparation of the patient are mandatory for obtaining a high-level examination.
Despite the continuous technological advances that have unleashed the diagnostic power of CCTA and allowed accu- rate diagnoses even in difficult clinical scenarios, some minor limitations should still be taken into account when performing CCTA examinations. The comprehensive defini- tion of a challenging patient embraces some clinical condi- tions that should be investigated in order to always guarantee a safe and accurate CT examination
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
Dispelling 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
koamabayili/VECTRON-author-checklist: VECTRON author checklist
No full textWe have done our best to complete the author checklist relating to the use of animals in the hut study. Note that the objective for the hut study was to evaluate the IRS treatment applications for residual efficacy against Anopheles mosquitoes, including the local An. coluzzii mosquito population. Cows were only used to attract mosquitoes into the huts and no tests were carried out directly on the cows. The author checklist is intended for use with studies where experiments are carried out on animals, which is why we have had such difficulty in completing this for the hut study, as many of the questions do not relate to how the cows were used
Author-wise bibliometric analysis based on entropy.
No full textAuthor-wise bibliometric analysis based on entropy.</p
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