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In situ monitoring of mussel populations in the Venice Lagoon by means of molecular biomarkers
No full textAbstract
The environmental stress of Mytilus sp. specimens collected from five specific sites in the Venice Lagoon (and from one offshore site nearby) has been investigated by means of different ecotoxicological biomarkers.
The study evaluated genotoxic and cytotoxic effects, such as DNA strand breaks and apoptosis, on the digestive gland cells of mussels by using the Single Cell Gel Electrophoresis Test, i.e. Comet Assay.
In order to assess the temporal and spatial trends of these biomarkers within the Venice Lagoon, the same sampling scheme was repeated in two field studies: mussels were collected monthly for a period of seven months from December 1999 to June 2000 and then from December 2005 to June 2006.
Regarding the temporal trend, the DNA damage values were lower in the 2006 study than in the 2000 study. However cell mortality values in the second monitoring were almost double those of the first one.
As for the spatial trend, in both studies mussels collected from the Venice Lagoon showed a higher level of DNA damage than offshore mussels, a trend that increased significantly as we moved from the lagoon border towards the lagoon interior
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
MONITORING ENVIRONMENTAL STRESS IN INDIGENOUS BLUE MUSSELS ( MYTILUS SP) SAMPLED FROM THE LAGOON OF VENICE
No full textThe environmental stress of Mytilus sp. specimens collected from the mussel populations of four specific sites inside the Lagoon of Venice
and from one offshore site nearby, has been investigated by means of an ecotoxicological biomarker. The approach has been applied to
the Lagoon of Venice in that it constitutes the drainage basin of a highly industrialized region. The study concerned the genotoxic effects,
evaluated as DNA strand breaks by single cell gel electrophoresis, in digestive gland cells and in hemocytes of mussels collected from
December 2005 to September 2006. In both tissues mussels collected inside the Lagoon showed higher levels of DNA damage compared
to specimens from the offshore site with a damage trend significantly increasing from the Lagoon border towards the inner part
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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