1,720,956 research outputs found
The development of suckling behaviour in two captive- born calves of bottlenose dolphin (Tursiops truncatus)
No full textFew and contrasting results have been obtained on nursing patterns of newborn and infant dolphin calves, so that the developmental profile of this behavior is still largely unknown. The aim of the present study was to observe, from birth to one year of age, the development of suckling behavior of two calves of Tursiops truncatus that were born three weeks apart in the same aquarium. Duration, frequency, lateralization, and day/night patterns of attempted (AS) and successful (SS) suckling episodes were scored. Observations followed this rationale: a) 1st week: 20 hours/day; b) 2nd-8th week: 20 hours/week; c) 9th-16th week: 20 hours/2 weeks; d) 17th-52nd week: 20 hours/3 weeks. Overall, the ontogenetic profile were rather similar in the two calves, and greater age-related changes were observed during the earlier compared to the later developmental period. AS frequency was high in the first postpartum phase. It readily decreased to very low levels thereafter, when SS frequency sharply increased, so that by the third day of life the correct behavior had almost totally replaced the attempts. SS duration increased over the first few days of life, and showed what appeared as a phase of adjustment around the second month. A circadian pattern was found during the first week of life for successful suckling, whose frequency and duration were higher during the night than during the day time. As for the last months of observation, individual developmental trends of suckling frequency were fairly consistent with the different time-courses of weaning. Finally, no definite evidence for a nipple preference appeared
Occurrence of bottlenose dolphins Tursiops truncatus in natural gas fields of the northwestern Adriatic Sea
No full textCommon bottlenose dolphins, Tursiops truncatus, were surveyed in offshore gas fields off Ravenna, Italy, between Spring and Autumn, 2001–2005. These visual surveys provide the first density estimates of bottlenose dolphins in the Northwestern Adriatic Sea south of the Po River. Since no study has examined the distribution of bottlenose dolphins relative to gas platforms, when dolphins
were encountered, their distance from the nearest gas platform was estimated and behaviour was assessed. Dolphins were sighted on ca. 36% of survey trips, which varied in duration from 1 to 6 h. Group size ranged from 1 to ~50 individuals, with no seasonal trend evident in the likelihood of encounter. Dolphin density was estimated to be approximately 80% higher within 750 m of gas platforms, relative to densities >750 m from platforms, although variability around the estimates was high. From a limited number of behavioural observations, slightly higher frequencies of feeding and milling behaviour were observed closer to gas platforms, whereas dolphins observed further away exhibited higher frequencies of socialising and travelling. Gas platforms are known to provide habitat for demersal fishes and act as aggregation points for pelagic fishes, and these data provide some support for the idea that bottlenose dolphins may utilise gas platforms opportunistically as feeding sites
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
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
Author-wise bibliometric analysis based on entropy.
No full textAuthor-wise bibliometric analysis based on entropy.</p
- …
