1,720,960 research outputs found
Sviluppo embrionale e diapausa in popolazioni di Tortrix viridana (Lepidoptera, Tortricidae) della Sardegna
Variability of beetle assemblages in Mediterranean cork oak woodlands: does the higher taxa approach reliably characterize a specific response to grazing?
Studying macroarthropod community responses to different land uses is particularly interesting in agroforestry for the conservation of Mediterranean landscapes, which need to be managed in terms of ecological and functional sustainability. Because of the sensitivity of many taxa to human impacts, we assessed the response of beetle assemblages at low taxonomic resolution (i.e. family level) to grazing in Mediterranean cork oak woodlands in northern Sardinia (Italy). Scarab assemblages were also analysed at the species level because of their ecological role in grazed areas. Cork oak woodland descriptors were also recorded in order to relate beetle assemblages to the forest structure. Over the entire sampling period, 4550 beetles belonging to 47 families were captured using pitfall traps. Multivariate analyses performed on ground-dwelling beetle data showed a distinct separation in terms of assemblages between grazed and ungrazed sites. The average diameter of cork oak trees and the degree of shrub cover were significantly linked to the beetle family assemblages. Constrained multivariate analyses indicated the significance of grazing, by both large and small domestic herbivores, and altitude, as variables determining the pattern of scarab beetle assemblages. Mantel test showed a significant correlation between the beetle and scarab dissimilarity matrices indicating a similar pattern for the two levels of identification. Our results show the predictive power of beetles at the family taxonomic level, as well as scarab beetles at the species level. These turned out to be valuable indicators in biomonitoring programmes in Mediterranean cork oak woodlands in order to increase the resilience of cork oak agroforestry systems under future global change scenarios
Assessing the response of ground-dwelling beetles communities to different land-uses in Mediterranea cork oak systems
In our study, we assessed the response of beetles communities at low taxonomical resolution to different Mediterranean cork oak land-use systems. Spatial variation of dung-beetles communities was also analyzed because of their potential role as ecological indicators in grazed areas
Indagini sull’entomofauna dannosa in un comprensorio cerasicolo montano della Sardegna centrale e tecniche alternative di lotta a Rhagoletis cerasi (L.)
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
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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