1,721,156 research outputs found
Présence de Cercyon (s. str.) depressus Stephens dans l'île Amsterdam (Océan Indien) [Col. Hydrophilidae]
No full textBameul Franck, Frenot Yves, Lebouvier Marc, Voisin Jean-François. Présence de Cercyon (s. str.) depressus Stephens dans l'île Amsterdam (Océan Indien) [Col. Hydrophilidae]. In: Bulletin de la Société entomologique de France, volume 94 (9-10), mars 1989. p. 308
The genus Luticola (Bacillariophyta) on Ile Amsterdam and Ile Saint-Paul (Southern Indian Ocean) with the description of two new species
Full text linkChattová, Barbora, Lebouvier, Marc, Haan, Myriam De, Vijver, Bart Van De (2017): The genus Luticola (Bacillariophyta) on Ile Amsterdam and Ile Saint-Paul (Southern Indian Ocean) with the description of two new species. European Journal of Taxonomy 387: 1-17, DOI: 10.5852/ejt.2017.38
Une gamme d’îles de référence, un atout majeur pour l’évaluation de programmes de restauration dans l’archipel de Kerguelen
No full textThe Kerguelen Archipelago is constituted by a main island (6 500 km²) and about sixty secondary islands (1-200 km²). Some of these islands are pristine, while some others have been colonized by introduced plants, invertebrate species and, in some cases, by one or several alien mammals. Programs of ecological restoration began in 1992 on three islands, Verte I., Guillou I. and Cochons I. (respectively 150, 145 and 165 ha) damaged by the presence of mammals (rabbits, rabbits-cats-mice, rabbits-mice). The management action was the eradication of rabbits by poisoning. Due to the existence of reference islands (with or without introduced mammals), and of control islands (presence of rabbits), the Kerguelen Archipelago offers an unusual opportunity to distinguish the effects of the management intervention from those of other factors. For example, synchronised vegetation monitoring of habitats on a control island (Cimetière I., colonized by rabbits) has shown the role of this mammal in controlling one introduced Asteraceae (Taraxacum officinale). After rabbit eradication, this plant drastically increased in cover on the three experimental islands. Moreover, results from Mayes I (without herbivores) and from the 4 other islands studied, emphasized the impact of the present climatic changes on the evolution of plant communities. This factor explains most of the decrease in cover of several native species, especially Acaena magellanica, with the timing of Dandelion’s success linked to open land appearance. These observations confirmed the value of contemporary reference sites to analyze the advantages of restoration programs and to conduct future actions.L’archipel de Kerguelen est constitué d’une île principale (6 500 km²) et d’une soixantaine d’îles secondaires (1-200 km²). Certaines sont totalement indemnes d’espèces introduites, d’autres ont été colonisées par des espèces végétales et des invertébrés allochtones, et d’autres encore sont occupées, de plus, par un ou plusieurs mammifères introduits. Un programme de restauration écologique concernant trois îles (145 à 165 ha) dégradées par laChapuis Jean-Louis, Frenot Yves, Lebouvier Marc. Une gamme d’îles de référence, un atout majeur pour l’évaluation de programmes de restauration dans l’archipel de Kerguelen. In: Revue d'Écologie. Supplément n°9, 2002. pp. 121-130
Luticola
No full textLuticola sp. Figs 72‒82 Description Light microscopy (Figs 72–82) Valves linear-lanceolate to elliptic-lanceolate in smaller specimens, with rounded, non-protracted apices. Valve dimensions (n = 12): length 10.7‒20.5 µm, width 4.5‒6.5 µm. Axial area narrow, linear. Central area wide, bow-tie shaped, clearly asymmetrical with the side bearing the isolated pore markedly wider. Isolated pore present in the central area, located halfway between the valve centre and margin. Raphe branches straight, deflected away from the isolated pore at both proximal and distal ends. Transapical striae punctate, radiate throughout the entire valve, 20‒24 in 10 µm. Remarks So far, this species has only been observed with light microscopy. Further studies and SEM observations will be necessary to determine its correct taxonomic position. The species was so far found in only two soil samples (A6 and A7) taken from Ile Saint-Paul. Both samples are dominated by L. beyensii, Humidophila brekkaensis, Pinnularia acidicola Van de Vijver & Le Cohu (Van de Vijver et al. 2002 a) and Hantzschia amphioxys.Published as part of Chattová, Barbora, Lebouvier, Marc, Haan, Myriam De & Vijver, Bart Van De, 2017, The genus Luticola (Bacillariophyta) on Ile Amsterdam and Ile Saint-Paul (Southern Indian Ocean) with the description of two new species, pp. 1-17 in European Journal of Taxonomy 387 on pages 10-11, DOI: 10.5852/ejt.2017.387, http://zenodo.org/record/113365
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
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