186,718 research outputs found
Chevret (1846-1983) : Louis Mathis, in L'Echo de la Presse
No full textChevret (1846-1983) : Louis Mathis, in L'Echo de la Presse. In: Revue d'histoire de la pharmacie, 22ᵉ année, n°87, 1934. p. 375
Chevret (1846-1983) : Louis Mathis, in L'Echo de la Presse
No full textChevret (1846-1983) : Louis Mathis, in L'Echo de la Presse. In: Revue d'histoire de la pharmacie, 22ᵉ année, n°87, 1934. p. 375
Directional asymmetry in Paussus favieri (Coleoptera: Carabidae: Paussini)
No full textMost animals have a body plan that is bilaterally symmetric,
at least externally. In some species, however, directional
asymmetry (DA) occurs, where there is a preferential
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direction of asymmetries, with one side that differs
systematically from the other. Although it was first thought
tat DA is relatively rare, subtle DA has been found in all
studies that examined asymmetries with geometric
morphometric techniques.
Until now all the studies have looked at only one structure
or at the comparison between modules. Here we analysed
directional asymmetries of several different parts showing
matching and object symmetries in Paussus favieri
(Coleoptera, Carabidae, Paussini). Because beetles of the
tribe Paussini are parasites of ants they are of great interest
because of the striking myrmecophilous adaptations. Most
of the species are extremely rare and localized, and their
biology and systematics are still poorly known. We used
geometric morphometric techniques to analyze the
variation of antennae (both left and right), head, pronotum
and abdomen in P. favieri (a relatively common species)
from different European and Maghrebian localities.
A clear and high evidence of a pattern of directional
asymmetry emerged from the analyses in all parts
examined. In particular principal component analysis
revealed a pattern of variation associated with DA, higher
in the antennae, but still present in all other body parts
except of the abdomen. In all analyses differences between
populations emerged as well.
Finally, Procrustes ANOVA provides similar results. For size
DA was statistically significant in all body parts except the
abdomen. For shape DA was significant only in the
antennae.
From our analyses antennae have emerged as the part
most under the DA, with a high shape and size variability.
Moreover differences between populations emerged, with
Moroccan population showing the highest differences.
We conclude that multiple body parts have directional
asymmetry, and the differences find between populations
show that directional asymmetry is evolving
Hommage du sieur Chevret d'un tableau central figuré des opinions et de l'éducation publique, lors de la séance du 18 juillet 1791
No full textLameth Charles Malo, comte de. Hommage du sieur Chevret d'un tableau central figuré des opinions et de l'éducation publique, lors de la séance du 18 juillet 1791. In: Archives Parlementaires de 1787 à 1860 - Première série (1787-1799) Tome XXVIII - Du 6 juillet au 28 juillet 1791. Paris : Librairie Administrative P. Dupont, 1887. p. 396
Author-wise bibliometric analysis based on entropy.
No full textAuthor-wise bibliometric analysis based on entropy.</p
Going Beyond Counting First Authors in Author Co-citation Analysis
Get PDFThe 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
Hommage du sieur Chevret d'un tableau central figuré des opinions et de l'éducation publique, lors de la séance du 18 juillet 1791
No full textLameth Charles Malo, comte de. Hommage du sieur Chevret d'un tableau central figuré des opinions et de l'éducation publique, lors de la séance du 18 juillet 1791. In: Archives Parlementaires de 1787 à 1860 - Première série (1787-1799) Tome XXVIII - Du 6 juillet au 28 juillet 1791. Paris : Librairie Administrative P. Dupont, 1887. p. 396
Appropriate Similarity Measures for Author Cocitation Analysis
Get PDFWe 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
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