1,720,996 research outputs found
Occhione: ricerca,monitoraggi,conservazione di una specie a rischio
No full textDalla prefazione: I gruppi specialistici costituiscono la forza propulsiva della ricerca e della conservazione per molte specie di uccelli. È attraverso la passione, la determinazione e la professionalità delle persone che si dedicano allo studio di una specie o di un gruppo di specie che si forma quel retroterra di conoscenze necessario a sviluppare linee e progetti di ricerca e a indirizzare le politiche di conservazione. L’uscita di questo libro è la dimostrazione di quanto un gruppo tematico di lavoro possa produrre. Questa felice raccolta di contributi ci mostra quanta attenzione sia ora rivolta all’Occhione; la sua presenza è capillarmente studiata in tutta Italia e nuove segnalazioni ampliano ogni anno la nostra conoscenza sulla sua distribuzione. Ma c’è di più in questo volume. C’è la dimostrazione della capacità di andare oltre la semplice documentazione della presenza, ci sono studi sul comportamento, sul canto e sull’ecologia. Mi auguro quindi di vedere ingrossate le fila di questo gruppo di ornitologi dediti all’Occhione e di poter leggere, nei prossimi anni, studi sempre più approfonditi sulla biologia di questa bellissima specie che sta coraggiosamente riconquistando il nostro Paese. A noi spetta il compito di ammirarla e difenderla
La vocalità dell’occhione (Burhinus oedicnemus): conoscenze attuali e nuove prospettive
No full textThe vocal repertoire by the Stone-curlew is broad and complex. Recent studies have shown that some adult calls are used in well-defined circumstances (e.g. in sexual or anti-predatory context), which suggests that they have specialized functions. The meaning of other calls is still unknown, but most of them are always used in non-random combination with the most typical vocalizations (gallop and kurlee call), suggesting the existence of a vocal syntax. The two typical chick calls were quantitatively described only recently; they develop well before hatching and remain almost structurally unchanged until fledging. Preliminary data on the vocal ontogeny indicate that near fledging young stone curlews undergo a process of voice breaking, consisting in the sudden emergence of new call types, which differ from the chick’s ones, while tending to take on the characteristics of adult vocalizations. In this period both chick calls and attempts to vocalize as adults coexist. The study of chick vocalizations and of the vocal relationships between parent and offspring can provide interesting insights on the presence and possibly on the mechanisms of parental recognition in this species. Future developments of bioacoustic researches on the Stone-curlew are further discussed
Uso di gps logger per descrivere il comportamento spaziale dell’occhione (Burhinus oedicnemus) in periodo riproduttivo: risultati preliminari
No full textIn this paper we evaluate the effectiveness of GPS data loggers to study the spatial behaviour of the Stone-curlew during the breeding period. Two females were tagged in the Taro River Regional Park (Parma, Italy) in the autumn 2013 and were followed during the next breeding season. The birds reacted well to tagging and for both some breeding attempts were recorded and at least one resulted successful, as proved by the observation of one 7-10-days old chick in July 2014. Regarding the spatial behaviour, the pattern observed was roughly comparable to what was recorded for the same study area using VHF tracking. The high number of recorded data, however, allowed to carry out a more detailed analysis of the behaviour of the animals, resulting in the identification of a series of behavioural changes during the reproductive season apparently not directly related to different phases of the breeding activity. The available data illustrate the great potential of the GPS tracking method, which has to be considered of extreme importance to plan effective conservation actions for the specie
Il ritorno dell’occhione (Burhinus oedicnemus) nel medio corso del fiume Piave
No full textIn the Piave River the Stone-curlew was considered extinct as breeder by the beginning of XX century. In recent years the species was detected again in Treviso province and the number of recorded breeding pairs showed a clearly positive trend. The breeding population estimated by means of binomial counts consisted of > 60 individuals in 2014. The available results underline the importance of the Piave River for the conservation of the species in the region and for understanding the process of re-colonization of the area
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
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
Polypropylene Recovery and Recycling from Mussel Nets
No full textMussels represent about one-third of all aquaculture products sold in the European Union. Theoretically, mussel production should be an environmentally friendly and sustainable activity (0.252 kg CO2 eq. per 1 kg of mussel produced against over 20 kg CO2 eq. per 1 kg of beef produced) but the abandoned plastic “socks” on the seabed and along beaches represent a significant environmental problem. The recovery and recycling of those polymer materials represents the proper management of the waste issue due to mussel farming. This study was performed to investigate, for the first time, the roles of the chemical oxidation actions on the detachment (and destruction) of organic matter (biofilm in particular) from the surface of the polypropylene “socks” used in sea farms in order to recover the polymer material and recycle it. In the experiments, oxidation by H2O2 and HNO3 was performed on the studied samples. The effects of the particle size of the fragments, oxidant concentration, agitation time and ultrasound application were determined. FTIR spectra and tensile mechanical properties of the samples after treatment were measured and compared with the virgin polymer material. The biodiversity and structure of the plastic-associated biofilm was also determined before and after the oxidation process. Based on the results of the characterization of the recovered polymer material, a process scheme was designed. The application of the developed process could significantly reduce the environmental risk associated with used mussel socks. The One LIFE (the EU’s funding instrument for the environment and climate action) Project was recently founded based on this research
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