1,721,045 research outputs found
A hormone-dependent post-translationally regulated mutant for investigating type I cadherin function
No full textType I cadherins are Ca2+-dependent cell adhesion molecules. Their function in early Xenopus laevis development has been extensively studied in recent years, by injecting synthetic mRNAs encoding dominant negative mutants with deletions of the extracellular domain into embryos. However, studies at post-gastrula stages have been hampered by the inabilityto progress through post-gastrula development in embryos expressing these mutant proteins. This problem has been partly overcome by injecting into a few targeted blastomeres in stage 6 N.F. embryos, but only restricted studies are possible with this technique. Several studies have made use of the hormone-binding domain (HBD), which is activated by hormones. In this study, we used this method to analyze the activity of dominant negative cadherins. We generated a mutant E-cadherin (AE-Cad, consisting of the cytoplasmic domain and transmembrane domain) fused to the hormone-binding domain of estradiol receptor (HBDER) and we validated this technique with functional analyses. The function of the mutant deltaE-HBDER was strictly dependent on hormone induction. This conditional mutant had the same effects and exerted the same dominant negative function as the corresponding constitutive mutant
Experimental Statistical Assessment of XPM Impact on Optical PMD Compensator Efficiency
Full text linkIn this paper, we report experiments on the statistical assessment of the reduction of PMD mitigator efficiency in presence of XPM effects. The XPM-induced depolarization limits compensation in polarization dispersive ultra-long haul system at 10 Gb/s
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
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