1,720,987 research outputs found
His bundle pacing: Clinical consequences of unnecessary right ventricle backup pacing
As a backup lead in right ventricle (RV) is often used in His-bundle pacing (HBP) implants, in sinus rhythm patients the His lead is connected to the left ventricular (LV) port of a CRT device. In current devices, the backup pacing will be delivered 100% of time due to cross-channel ventricular refractory periods. Beyond an impact on battery, unnecessary RV pacing could find excitable tissue and capture a portion of the myocardium tissue potentially reducing the benefits of physiological HBP as shown in this case report where the switch from biventricular to LV-only pacing improved acute and 2-month echocardiography parameters
Senile hypertension: Risk factors, and as risk factor itself
Hypertension is widespread amongst the elderly, affecting more than 50% of them, with a progressive age related increase, in prevalence of isolated systolic hypertension. All the hypertension risk factors are analysed, whereas a primary role should be assigned to congenital changes in cellular sodium transport systems, manifesting by the aging, in the presence of modulating factors as hyperinsulinism. The importance of antihypertensive therapy with calcium-channel blockers and angiotensin-converting enzyme (ACE) inhibitors to prevent cardiovascular disease, is confirmed in elderly patients
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
His–Purkinje system longitudinal dissociation: From bench to bedside. A case of output-dependent fascicular capture
Introduction: Histological studies reported that the His bundle (HB) is partitioned into narrow cords by collagen running in its long axis, providing the anatomical setting necessary for its longitudinal dissociation. Further confirmations came from the demonstration that direct HB pacing normalizes the QRS axis and duration in subjects with proximal HB lesions causing bundle branch block. However, there is no evidence of the possibility of selective HB partitions pacing destined to the composition of branches and fascicles. Methods and Results: We describe a case of intra-Hisian left bundle branch block in which permanent distal HB pacing corrects left ventricular delay and produces different QRS morphology at different voltage outputs, as an expression of different selective HB compartments recruitment. Conclusion: This case would strengthen the limited data in the literature about HB longitudinal dissociation
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
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