1,721,617 research outputs found
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
Love getaway: dispersal pattern and distance of the crested porcupine
No full textThe crested porcupine Hystrix cristata is undergoing a marked range expansion in Italy, and it is reaching the northern regions, where it was historically absent. We studied its dispersal ability by marking 86 subadult individuals through coloured tapes on dorsal quills, in contrasting environmental context (i.e. coastal scrubland, deciduous woodland, suburbs, rural areas and farmlands), in Southern Tuscany. Recaptures occurred only for 14 (16.3%) of them, allowing us to evaluate dispersal patterns, which ranged from 180 to 4896 m. We showed that no sexual difference occurred in dispersal distances, as expected by the monogamous mating system of this rodent. The season did not affect dispersal patterns significantly, although most of these movements occurred at the peak of the main reproductive season. Dispersal distance increased with increasing home range and with increasing woodland cover (i.e. % of study site covered by woodland). Forest reexpansion in Italy may thus have promoted the range expansion by this species during the last 40 years
Displacement interference between wild ungulate species: does it occur?
No full textAmong mammals, interspecific interference is common in carnivores, primates and rodents, but it seems to be a rare occurrence in ungulate communities. We summarised the knowledge on interspecific displacements through behavioural interactions between ungulate species in temperate areas to evaluate the conditions under which ungulate behavioural competitive interactions may occur. We found 18 studies reporting interspecific behavioural dominance between wild ungulates, for a total of 37 reports of interspecific displacement, involving 15 species. Only eight reports showed over more than 10 displacements. Over 60% reports involved at least one alien species. The larger one displaced the smaller one in 69% reports involving only native species and in 58% reports involving at least one alien species. Among ungulates, resource exploitation rather than behavioural interference seems to be the main mechanism for interspecific competition. Behavioural interference may increase when non-coevolved species come into contact (e.g. alien taxa, or species expanding their distribution range following environmental changes), in turn generating the potential for interspecific competition
Worldwide impact of alien parrots (Aves Psittaciformes) on native biodiversity and environment: A review
No full textMore than 16% of parrot species (Aves Psittaciformes) of the world have currently established at least one breeding population outside their natural distribution ranges. Though including the most introduced bird species all over the world, their interactions with native biodiversity and environments are still poorly known. In this paper, we summarize current knowledge about impacts of introduced Psittaciformes and we identify possible gaps to be filled with future research. Breeding site requirements of alien parrots, e.g. trunk cavities, indicate potential routes of direct and indirect competition with native hole-nesting bird species. Interactions with arboreal rodents, bats and insects are poorly documented, but appear to be limited. Psittaciformes potentially affect economy and human wellness, being responsible for damage to crops and to electrical infrastructures. Association with noise pollution has also been suggested, as many alien populations breed in urban parks or close to human settlements. Psittaciformes are potential reservoirs of Chlamydophila psittaci, the etiological agent of human psittacosis, and other diseases transmittable to humans and wildlife. Less is known about impact on native flora as well as on ecosystem functions. Predictive research and information on ecosystem recovery after parrot removal are scarce too, as eradication programs are often hampered by the emotional affiliation linked to these birds. © 2014 Dipartimento di Biologia, Università di Firenze, Italia
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
koamabayili/VECTRON-author-checklist: VECTRON author checklist
No full textWe 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
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