1,721,131 research outputs found

    Instability of Neutral Eady Waves and orography

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    A quasigeostrophic Eady model is used to study the instability properties of finite-amplitude Eady waves and relate them to the disturbances generated by isolated bottom topography. It is found that when the amplitude of the primary wave is small the unstable perturbations are slightly deformed three-dimensional Eady modes, with growth rates and phase speed near the values obtained for the instability of the mean zonal state only. When the amplitude of the primary wave is large the most unstable modes are frontal waves, with growth rates increasing with the amplitude of the primary wave and locked in phase with it. The transition between the two regimes occurs for amplitudes of the primary wave around 10 mb. When a wave packet is generated by the interaction of a large-amplitude primary wave with orography, the character of the instability is absolute—that is, the local perturbation grows exponentially—while in the small amplitude, as well as in the zonal, case, the perturbation is advected downstream while growing, so that at any fixed spatial point only the base state remains as t → infinity

    Going Beyond Counting First Authors in Author Co-citation Analysis

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    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

    Sodium Channel Blockers as Therapeutic Target for Treating Epilepsy: Recent Updates

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    The voltage-gated sodium channels (VGSCs) are a family of membrane proteins forming a pore, through which they selectively conduct sodium ions inward and outward cell's plasma membranes in response to variations of membrane potentials, playing a fundamental role in controlling cellular excitability. Growing evidences suggest that abnormal VGSCs are involved in the pathophysiology of both acquired and inherited epilepsy. Approximately two dozen drugs are currently marketed for the treatment of epilepsy and most of them act as sodium channel blockers, preventing the return of the channels to the active state by stabilizing the inactive form. Despite the many drugs on the market, 30% of patients continue to experience seizures even in the presence of optimal doses of AEDs, while others continue to suffer from medication induced side effects. Thus, there is a great need to continue the search for new AEDs that are not only more effective, but also have a better side effects profile. For this reason, many efforts have been made in the recent years to identify new sodium channel blockers for the treatment of epilepsy. These studies have led to different classes of compounds, characterized by a great structural diversity. The aim of this review is to provide an introduction on the structure and function of the sodium channels, followed by a brief historical perspective on the sodium channel blockers in use as anticonvulsant drugs. Moreover, it will focus on the medicinal chemistry of the sodium channel blockers recently published (2008-2011) and the drug design/molecular modeling studies related to the receptor

    Variations on the Author

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    “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

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    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

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    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

    Author Index

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    koamabayili/VECTRON-author-checklist: VECTRON author checklist

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    We 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
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