1,721,008 research outputs found

    Record of the bluespotted cornetfish Fistularia commersonii Rüppell, 1838in the Ligurian Sea (NW Mediterranean)

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    The record of one adult female of the bluespotted cornetfish Fistularia commersonii Rüppell, 1838, caught using trawl nets in coastal waters near Sanremo, Western Ligurian Sea, in October 2007 is reported. This record confirms the rapid spread of the species and suggests a possible fast expansion toward French and Spanish waters by means of the Western Mediterranean Northern Current. Previous records in Italian waters apparently indicate a pioneer phase of colonization by adult fish and a stabilized phase, with adult and young fish, four years later

    Large pelagic fish, swordfish, bluefin and small tunas, in the Ligurian Sea: biological characteristics and fishery trends.

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    This article presents a review and summary of the data on large pelagic fish, collected over the period 1990–2007, thanks to national and European Community research programmes. Swordfish are present in the Ligurian Sea at all life history stages. Time series of longline fishing catch per unit effort (CPUE) values showa good exploitation status, possibly related to the dismission of past questionable fishing technics (e.g. ‘spadare’ nets). CPUE values were also negatively related to North Atlantic oscillation: climatic factors probably had synergic effects. Bluefin is present in the Ligurian Sea with mainly schools of young fish aged 1–4 years, which feed on small pelagic fish and on the Ligurian krill Meganyctiphanes norvegica. Recent limitations on catches have severely reduced local fishing activities. Following the dismission of purse seiners, artisanal hook-based fisheries should be maintained, regardless of the length of fish caught, as a way of monitoring stock status. The two most abundant species of small tuna, Sarda sarda and Auxis rochei rochei, are present in the Ligurian Sea at all life stages. In particular, Auxis rochei rochei is a commercially neglected species which, in terms of larval occurrence, is the most abundant in the Mediterranean. Physiomorphological and genetic studies have been recently carried out in order to improve forthcoming exploitation

    First data on plastic ingestion by blue sharks (Prionace glauca) from the Ligurian Sea (North-Western Mediterranean Sea)

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    Few studies have focused so far on plastic ingestion by sharks in the Mediterranean Sea. The aim of this paper was to determine, for the first time, the plastic litter ingested by blue sharks (Prionace glauca), categorized as “Critically Endangered” in the Mediterranean Sea by IUCN, caught in the Pelagos Sanctuary SPAMI (North-Western Mediterranean Sea). The analysis of the stomach contents was performed following the MSFD Descriptor 10 standard protocol implemented with FT-IR spectroscopy technique. The results showed that 25.26% of sharks ingested plastic debris of wide scale of sizes from microplastics (<5 mm) to macroplastics (>25 mm). The polyethylene sheetlike user plastics, widely used as packaging material, are the most ingested debris. This research raises a warning alarm on the impact of plastic debris on a threatened species, with a key role in the food web, and adds important information for futures mitigation actions

    Going Beyond Counting First Authors in Author Co-citation Analysis

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    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

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    “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

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    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

    Comprehensive Italian Annotated Bibliography on Swordfish (Xiphias gladius, Linnaeus, 1758)

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    The Italian scientists have a long tradition of studies and research on swordfish (Xiphias gladius). This species is certainly one of the most important for the Italian fishery since old historical times, mentioned in many ancient books. This paper lists together the many papers published so far by Italian scientists, concerning the biology of this species, the fisheries and many other scientific and cultural issues. The aim is to provide a comprehensive annotated bibliography, with specific keywords in English, for making available all these documents independently from the original language of the text. So far, we found 916 papers on swordfish but the bibliography is surely incomplete, because of the many papers published over the centuries in many places. We also included additional 47 titles concerning electronic or audio-visual documents. This bibliography, updated till 2020, was set together to serve the scientists and to help them in finding some rare references that might be useful for their work

    Dispelling the Myths Behind First-author Citation Counts

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    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

    Comprehensive Italian Annotated Bibliography on the Mediterranean Spearfish (Tetrapturus belone, Rafinesque, 1810), and on Other Billfish and Spearfish Species

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    The Italian scientists have a long tradition of studies and research on many large pelagic species, including spearfishes and billfishes. One of these species (Tetrapturus belone), the only one which can be considered really Mediterranean, can show relevant catches in some years, while other species are incidental or vagrant. This paper is providing a comprehensive bibliography on these species, listing a total of 175 papers published so far by Italian scientists, concerning the biology, the fisheries and many other scientific issues. The aim of this paper is to improve as much as possible the access to the bibliography, with specific keywords, even if it is still surely incomplete, because sometimes the information on Mediterranean spearfish or other more rare billfish species is hidden in some papers on other pelagic fisheries. This bibliography was set-up together to serve the scientists and to help them in finding some rare references that might be useful for their work
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