1,720,967 research outputs found
Evidence of Population Decline in Common Eiders Breeding in Western Greenland
Full text linkIn the Arctic, there is great concern for several eider populations, including the northern common eider (Somateria mollissima borealis) breeding in Canada and Greenland. In 1998-2001, extensive ground surveys were conducted on 937 potential nesting islands in West Greenland, covering most of the districts of Ilulissat, Uummannaq, and Upernavik (69°15\u27 N to 74°05\u27 N). On 216 islands within 106 eider colonies, 4097 ±468 active nests were identified. In 15 colonies where comparable and well-documented surveys were conducted approximately 40 years ago, the study shows a population decline of 81% (from 3361 to 624 nests). A rough comparison shows that of 51 eider colonies surveyed in 1920, 1960, or 1965, 71% either were gone or had declined in breeding numbers when resurveyed in 1998-2001. At the colony level, the 1998-2001 surveys revealed large year-to-year variations in nesting numbers. The reason for the overall decline is not clear. However, there is circumstantial evidence that harvest of common eiders in West Greenland is a key factor. The results urgently call for more cautious management of the northern common eider population.On se préoccupe beaucoup dans l\u27Arctique de plusieurs populations d\u27eiders, y compris l\u27eider à duvet (Somateria mollissima borealis) qui se reproduit au Canada et au Groenland. De 1998 à 2001, on a procédé à de vastes relevés au sol sur 937 îles susceptibles d\u27abriter des nids dans l\u27ouest du Groenland, une zone qui recouvrait la plupart des districts d\u27Ilulissat, d\u27Uummannaq et d\u27Upernavik (69° 15\u27 de latit. N. à 74° 05\u27 de latit. N.) Sur 216 îles situées à l\u27intérieur de 106 colonies d\u27eiders, on a identifié 4097 ± 468 nids actifs. Dans 15 colonies où des relevés comparables et bien documentés ont été effectués il y a 40 ans, l\u27étude révèle une baisse de la population de 81 % (soit de 3361 à 624 nids). Une première comparaison montre que des 51 colonies d\u27eiders étudiées en 1920, 1960 ou 1965, 71 % avaient soit disparu, soit enregistré une baisse du nombre de paires lors des nouveaux relevés effectués entre 1998 et 2001. Au niveau de la colonie, ces derniers relevés montraient d\u27importantes variations interannuelles dans le nombre de nids. La raison de la baisse globale n\u27est pas très claire, mais certains indices prouvent que le prélèvement de l\u27eider à duvet dans l\u27ouest du Groenland est un facteur clé. Les résultats appellent à une plus grande prudence dans la gestion de la population de l\u27eider à duvet, et ce, au plus vite
Remote time-lapse photography as a monitoring tool for colonial breeding seabirds:a case study using Thick-billed Murres (<em>Uria lomvia</em>)
No full textGoing 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
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