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Ipotesi patogenetica: correlazione Burning mouth syndrome (BMS) , gusto e disfunzione tiroidea
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Influence of an acid environment on hardening of SuperEBA and MTA
No full textBackground. Super EBA (SE) and MTA are considered to be among the best retrograde filling materials used in endodontic surgery. Since the post-operative course is characterised by phlogosis and an acid pH, it is worth asking whether this environment influences the hardening of these materials. The aim of this study was to evaluate in vitro the influence of pH on the Vickers hardness of MTA and SuperEBA. Methods and materials. Twelve MTA and 12 SuperEBA disks were prepared and left to harden, for 24 hours and 1 hour respectively, in pH5 and pH7 buffer solutions (n. 6 for each group). After careful polishing of the free surface the final hardness was evaluated using a micro-hardness meter; an optical microscopy assessment was also performed as a qualitative analysis to evaluate the indentations. Data were analysed with one-way ANOVA and Scheffe post hoc test. Results. Means of Vickers values and standard deviation were: pH7 MTA 38,59(2,59); pH5MTA 4,02(1,57); pH7 SE 18,46(5,38); pH5 SE 20,65(5,49). MTA at neutral pH is associated with the best hardness; this is dramatically reduced if the samples are exposed to an acid solution. Instead, SuperEBA, characterised by a lower hardness, is practically unaffected by changes in the pH level, showing only a slight increase in an acid pH environment. The differences were statistically significant (p<0,001) except for the groups of ph7 SE vs pH5 SE. Conclusions. An acid pH significantly influences the hardness of MTA but not of SuperEBA
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
PROPOSTA DI UNA TECNICA DI RE-BONDING APPLICATA SUI DENTI POSTERIORI RICOSTRUITI CON TECNICA INDIRETTA
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