1,721,209 research outputs found
Ferritin and Transferrin Receptor 1: cryo-EM structural studies and protein engineering
Full text linkThe principal aim of this thesis is the structural determination of the residues involved in the complex between the human Ferritin H-chain (HFt) and the human Transferrin Receptor 1 (hTfR1 or CD71) at near to atomic resolution.
HFt nanoparticles represent one of the most appropriate vectors for cellular delivery of molecules thanks to their internalization by CD71, a transmembrane receptor overexpressed in most cancer cell types. As such, literature is continuously enriched by successful biomedical applications of this interaction; nevertheless, the epitopes of their recognition are to date unknown. To this end, we exploited single-particle cryo-electron microscopy (cryo-EM): this technique is currently under intense technological development and can now be used as a convenient method to determine atomic structures of protein complexes. So, we took advantage of modern cryo-electron microscopes and GPU-equipped computer clusters for single particle analysis calculations. Through the CD71-targeted distribution of specific payloads, the cellular internalization property of HFt might be used for a plethora of purposes, ranging from anticancer therapy to image-enhancement for diagnostics: the side aims of this thesis deal with cryo-EM structural analysis of two different Ferritins chimeras whose constructs have been designed and optimized by our group
Saturation of tearing modes in Reversed Field Pinches with locally linear force-free magnetic fields and its application to Quasi-Single-Helicity states
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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
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