1,720,979 research outputs found
The valid genus name of the European freshwater blennies, Ichthyocoris or Salariopsis (Teleostei: Blenniidae)?
Vecchioni, Luca, Arculeo, Marco, Hundt, Peter J., Marrone, Federico (2022): The valid genus name of the European freshwater blennies, Ichthyocoris or Salariopsis (Teleostei: Blenniidae)? Zootaxa 5162 (1): 99-100, DOI: https://doi.org/10.11646/zootaxa.5162.1.
On the Occurrence of the Invasive Freshwater Limpet Ferrissia californica (Mollusca: Gastropoda: Planorbidae) in Japan
Two members of the genus Ferrissia Walker, 1903, namely Ferrissia nipponica (Kuroda, 1949) and F. japonica Habe and Burch, 1965, have been reported to occur in Japan, but due to a lack of molecular data, doubts have been expressed as to their validity. Furthermore, the possible presence of allochthonous Ferrissia taxa has been stated under a variety of names, so that even now there is no consensus on their presence and identity. Recently, freshwater limpets belonging to the planorbid genus Ferrissia were collected in an irrigation trough on the Izu island of Hachijōjima, Tokyo, Japan. Molecular identification of the collected specimens, based on a fragment of the large ribosomal subunit 16S (mtDNA), unequivocally proved that they belong to the allochthonous, invasive species Ferrissia californica (Rowell, 1863), the protagonist of a relentless cryptic invasion worldwide to which can Japan can now be added. The shells of the collected specimens show some scars, which bear testimony to the fragile nature of the shell and, possibly, to the paucity of calcium in the inland waters of Hachijōjima
The DNA barcoding of Mediterranean combtooth blennies suggests the paraphyly of some taxa (Perciformes, Blenniidae)
A dataset including novel and publicly available mtDNA COI sequences of 14 Mediterranean combtooth blenny species belonging to nine genera was assembled in order to provide a reference dataset for DNA barcoding studies. Some inconsistencies in the current taxonomy of some genera were observed. In particular, the monophyly of the genera Parablennius and Salaria is not supported by the present dataset and the absence of reciprocal monophyly between the morphospecies Salaria basilisca and S. pavo questions their status and stresses the need of a revision of the genus Salaria
Going Beyond Counting First Authors in Author Co-citation Analysis
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
Variations on the Author
“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
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
Investigating heavy metals and other elements in Procambarus clarkii and environmental matrices from three wetlands of Sicily (Italy)
A qualitative and quantitative analysis of 18 elements was conducted on Procambarus clarkii and its environmental samples to evaluate its potential as a bioindicator species. Analysis of biological samples was carried out to both assess the safety of the use of raw materials and, together with environmental samples, to assess the contamination status of the sampled sites.
Signifcant diferences highlighted by the PERMANOVA, HCA and PCA analyses confrmed the valid use of P. clarkii as a bioindicator of the health status of the studied ecosystem. The bioaccumulation factor (BAF) and the biotic sediment accumulation factor (BSAF), except in a few cases, reported values below the bioaccumulative criterion and showed the highest BAF values for manganese, iron and barium in the exoskeleton while the highest BSAF values concerned mercury, copper and zinc in the muscle and barium in the exoskeleton. These fndings indicate that, for most of the trace elements (TEs), the extent of pollution at these sites is such that it does not result in signifcant bioaccumulation in the muscle and exoskeleton of P. clarkii. The TE concentration levels signalled mild contamination of the sampling sites, proving a good health status of the studied aquatic ecosystem. Finally, the results obtained in P. clarkii muscle were below the threshold limits of EU Regulation 2023/915 suggesting that these edible parts are safe for human consumption
Dispelling the Myths Behind First-author Citation Counts
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
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