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Randomized clinical trials of PFO closure for migraine headaches (MIST, PRIMA, PREMIUM)
Full text linkA number of observational studies describe patients with chronic and debilitating migraine headaches who experienced improvement or resolution of their migraine attacks following percutaneous patent foramen ovale (PFO) closure. These observations led to 3 randomized controlled trials to further investigate the efficacy and safety of PFO device closure plus standard of care medical therapy versus medical therapy alone (with or without a sham procedure), for the treatment of migraine headaches. The randomized trials failed to meet their primary endpoints that were defined to replicate the results of prior observational studies. Yet, all showed partial benefits in their subanalyses. The goal of this chapter is to discuss the clinical trials of PFO closure for migraine headache, with emphasis on the lessons learned, limitations, and meta-analyses of these studies. This chapter will serve to provide clinicians with insight to help guide their migraine patients who are found to have a PFO on echocardiographic testing
Migraine headache: Clinical association with PFO and observational studies
No full textMigraine, according to the International Headache Society, is a primary headache disorder and is classified as migraine with (MWA) or without aura (MWoA). Rarely migraine aura, with or without headache, can be secondary and may occur as the first manifestation of cerebral ischemia or repeatedly as a symptom of several neurological disorders. For both primary and secondary aura, cortical spreading depolarization has been shown to be the neurophysiological substrate that explains the phenotypic similarities. MWA has also been shown to double the risk of stroke though rare in absolute terms. A potential mechanism may be a link with patent foramen ovale (PFO) that is frequently present in stroke without other identifiable causes or in migraine stroke. Case control studies have demonstrated a higher prevalence of migraine in individuals with PFO compared to controls, and a higher prevalence of PFO in individuals with migraine, indicating an association of migraine and PFO. Furthermore, PFO closure may reduce MWA attacks according to some case control studies. This supports the hypothesis that microemboli may trigger cortical spreading depolarization and migraine aura, while PFO closure may reduce MWA attacks. Another observational study indicated that PFO closure reduces migraine headaches in PFO migraine patients who respond favorably to P2Y12 platelet inhibitors. However, both hypotheses have yet to be proven by randomized controlled trials focusing, unlike previous trials, on migraine patients who suffer an aura in most or all of their attacks or those who experience headache reduction with P2Y12 platelet inhibitors
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
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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