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A temporal analysis of the foraging flights of feral pigeons (Columba livia f. domestica) from three Italian cities
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Sexual Dichromatism In Mediterranean Storm Petrels Hydrobates Pelagicus Melitensis
Full text linkSexual dichromatism in mediterranean storm petrels Hydrobates pelagicus melitensis. We propose the use of a non-invasive technique for sexing the Mediterranean subspecies of the European storm petrel Hydrobates pelagicus melitensis. We found that this subspecies shows sexual dimorphism in rump band length and wing length. We found that storm petrels can be sexed using discriminant analysis and/or the product of wing length * rump band length. Fast and cheap sex identification methods can improve conservation programs and population studies of this species
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
Forecasting ocean warming impacts on seabird demography: a case study on the European storm petrel
Full text linkBottom-up climatic forcing has been shown to be influential for a variety of marine
taxa, but evidence on seabird populations is scarce. Seasonal variation in environmental conditions
can have an indirect effect on subsequent reproduction, which, given the longevity and
single-brooding of seabirds, may affect population dynamics. Our study focuses on linking the
effect of oceanographic conditions (from 1991 to 2013) to the fecundity and consequently pop -
ulation growth rate of the Mediterranean subspecies of the European storm petrel Hydrobates
pelagicus melitensis. In this study, we examined 23 yr of > 5400 capture–mark−recaptures (CMR)
and modelled the probability of skipping reproduction as a function of oceanographic variables
using CMR models. We demonstrate that a decrease in sea surface temperature in the pre-breeding
period negatively influences skipping propensity, and therefore hypothesize that this behaviour
would have significant influence on population abundance over time. For this reason, we analysed
population growth as a function of skipping probability as affected by oceanographic
conditions. We used stochastic demographic models to forecast the fate of the population, and
evaluated contrasted environmental condition scenarios. As a result, we found that a decrease in
frequency of cold winter events would probably reduce skipping propensity, with a positive effect
on the population as a whole
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
Use of captive bred passerines to monitor human disturbance using corticosterone metabolites
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