1,721,089 research outputs found

    Spread of Alsidium corallinum C. Ag. in a Tyrrhenian eutrophic lagoon dominated by opportunistic macroalgae

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    In 2007, the Rhodophyceae Alsidium corallinum C. Ag., a marine taxon, bloomed in the eutrophic lagoon of Orbetello (Tuscany, Italy) for the first time, becoming the dominant species in spring and summer. In November, its biomass collapsed. The hypothesis examined in this study is that the bloom expressed a relatively low eutrophic level of the ecosystem after intense disposal of accumulated sedimentary organic matter (OM) by dystrophic processes in the two years preceding the bloom. To verify the hypothesis, we compared water physical–chemical variables, sediment redox (Eh) and OM, and standing crops of macroalgae and seagrass from the database of routine monitoring between 2005 and 2008.Wealso used dissolved nutrient data obtained in 2007 and 2008, as well as data on chlorophyll and total suspended matter in the water column during the microalgal bloom of 2007, and C, N and P content in thalli of the Chlorophycea Chaetomorpha linum and the Rhodophyceae Gracilariopsis longissima and A. corallinum obtained in 2007. In 2007, unusually low values of dissolved inorganic nitrogen (DIN) were recorded. Combined with stable values of soluble reactive phosphorus (SRPs), low DIN led to a reduction of about one order of magnitude in the DIN:SRP atomic ratio with respect to the past and to 2008. G. longissima accumulated C, N and P more than the other species and A. corallinum proved to be less demanding. Sediment OM was lower in the autumn of years characterized by dystrophy, confirming that summer dystrophic events coincided with maximum energy dissipation in this ecosystem. However, as soon as OM and DIN values increased (2008), the vegetation shifted towards blooms of G. longissima and C. linum, while A. corallinum almost disappeared. The results sustain the hypothesis that the bloom of A. corallinum was due to a decline in DIN that limited G. longissima, and to intense turbidity of the water caused by microphytes that developed after the dystrophic event of summer 2006. The latter probably limited the development of C. linum, which could only develop at the edges of the lagoon

    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

    La Persia e il mondo classico, La Parola del Passato, vol. 27

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    Debergh-Rassart M. M. La Persia e il mondo classico, La Parola del Passato, vol. 27. In: Revue belge de philologie et d'histoire, tome 52, fasc. 4, 1974. Histoire (depuis l'Antiquité) — Geschiedenis (sedert de Oudheid) p. 1034

    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

    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

    Author Index

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    koamabayili/VECTRON-author-checklist: VECTRON author checklist

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    We have done our best to complete the author checklist relating to the use of animals in the hut study. Note that the objective for the hut study was to evaluate the IRS treatment applications for residual efficacy against Anopheles mosquitoes, including the local An. coluzzii mosquito population. Cows were only used to attract mosquitoes into the huts and no tests were carried out directly on the cows. The author checklist is intended for use with studies where experiments are carried out on animals, which is why we have had such difficulty in completing this for the hut study, as many of the questions do not relate to how the cows were used

    La scultura di S.Polieucto e la presenza della Persia nella cultura artistica di Costantinopoli nel VI secolo

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    Il ritrovamento della chiesa di S. Polieucto nel 1960 ha posto un problema che i precedenti studiosi non hanno saputo risolvere: da dove vengono gli elementi persiani presenti nelle decorazioni scultoree? La risposta fino allora insufficiente era: per il tramite di manufatti come le stoffe. Lo studio analitico dei singoli motivi mostra che l’autore, di Costantinopoli, degli schemi decorativi aveva una conoscenza diretta e approfondita dell’arte della Persia, e ci sono influenze anche per quanto riguarda l’architettura. Lo studio permette di chiarire pure punti ancora controversi per la stessa arte persiana, come la datazione dei capitelli a cesto, che hanno determinato la scelta rivoluzionaria dei capitelli di S. Polieucto, conseguenza inevitabile dell’adozione della copertura a volte
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