Sexe et âge ratios chez le canard siffleur Anas penelope L. en période hivernale en Europe de l'Ouest

Data on the sex- and age-ratios of Wigeon were collected over five years. In the Camargue, data from three winters show that adult males arrived earlier than other birds ; that immature males passed through the delta in autumn and spring ; and that the sex-ratio remained remarkably stable (1.5 males per female). Short term observations over two winters covering western Europe (Spain-Holland, and Morocco-Holland) provided evidence for spatial segregation of the main sex- and age-classes. Adult males tended to remain further north in the wintering area, with immature males and the females further south. This difference in distribution was more pronounced between age-classes than between the sexes. It is suggested that aggression, through social hierarchies, may be one factor which causes these differences in distribution. Males dominate the Wigean population numerically even in the south of the wintering area. It is suggested that this unequal distribution of the ages and sexes, whatever its cause, may have important consequences for the species'demography2014-12-19T14:26:53

Planification côtière en Afrique de l'Ouest : retour d'expérience en Guinée-Bissau.

National audienceThis contribution reports the context of implementation of a GIS which is intented for coastal planning in Guinea Bissau in the context of the creation of a biosphere reserve. It takes stock of the productions of 10 years of collaboration between research and management of the north and the south. This experiment has become a model in the coastal countries of West Africa.Cet article relate le contexte de la mise en oeuvre d'un SIG à vocation de planification côtière en Guinée-Bissau dans le contexte de création d'une réserve de biosphère. Il fait le bilan des productions et des acquis de 10 ans de collaboration entre des organismes de recherche et de gestion territoriale du nord et du sud. Une expérience qui fait école au sein des pays côtiers d'Afrique de l'Ouest

Planification côtière en Afrique de l’Ouest. Retour d’expérience SIG en Guinée-Bissau

Cet article relate le contexte de la mise en œuvre d’un SIG à vocation de planification côtière en Guinée-Bissau dans le contexte de création d’une réserve de biosphère. Il fait le bilan des productions et des acquis de 10 ans de collaboration entre des organismes de recherche et de gestion territoriale du nord et du sud. Une expérience qui fait école au sein des pays côtiers d’Afrique de l’Ouest.This article reports the context of the implementation of a GIS which is intended for coastal planning in Guinea Bissau in the context of the creation of a biosphere reserve. It takes stock of the productions and the assets of 10 years of collaboration between research and territorial management organisations of the north and south. This experiment has become a model in the coastal countries of West Africa

Étude sur l'évolution des coutumes kabyles, spécialement en ce qui concerne l'exhérédation des femmes et la pratique du hobous / par Pierre Hacoun-Campredon, ...

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Diversity of approaches in artificial intelligence: an opportunity for discoveries in thoracic imaging

International audienc

The Monk scal (Monachus monachus) population of Mauritania

Observation, en octobre 1988, de la population de deux grottes de la Côte des Phoques. La possibilité de pénétrer à l'intérieur des grottes a permis d'obtenir une estimation assez précise du nombre d'individus et de leur répartition par classes de taille. Les comptages montrent une stabilité des effectifs depuis une dizaine d'années sur la Péninsule du Cap Blanc. La proportion des jeunes dans les échantillons est élevée. Cette population est sérieusement menacée par les activités d'un nombre toujours croissant de pêcheur

La population de Phoque moine (Monachus monachus) de Mauritanie

An attempt was made in October 1988 to more accurately estimate the population of monk seals Monachus monachus living along the western coast of the Cap Blanc peninsula, Mauritania. Seals were only observed close to three of the four caves shown on figure 1. We were able for the first time to enter two of these caves (1 and 3) from the sea, but failed to do so for cave 4 : however, we ascertained that cave 4 also harboured some seals. No seals were observed elsewhere along the penisula in 1988, except at its very tip, where 5 large individuals appear to be resident in the small Nature Reserve of Cap Blanc. The Monk seal population of the peninsula can be presently estimated at 1 30 individuals at least. It has apparently remained stable over the last ten years. The percentage of young individuals in the sample observed was of ca 20-27 % . This population is seriously threatened by the activities of an ever increasing number of both local fishermen and offshore trawlers.En octobre 1988, la population de Monachus monachus de deux grottes de la côte des phoques (Mauritanie) a été observée. La possibilité de pénétrer au fond de ces grottes a permis d’obtenir une estimation assez précise du nombre d’individus et de leur répartition par classes de taille. Sur l’ensemble des secteurs visités (deux grottes visitées complètement, une partiellement, et l’extrémité du Cap Blanc), la population de phoques est estimée à environ 130 individus. Ces comptages montrent une stabilité des effectifs depuis une dizaine d’années sur la Péninsule du Cap Blanc. La proportion de jeunes dans les échantillons est élevée : 20 à 25 %.Francour Patrice, Marchessaux Didier, Argiolas Alain, Campredon Pierre, Vuignier Gérard. La population de Phoque moine (Monachus monachus) de Mauritanie. In: Revue d'Écologie (La Terre et La Vie), tome 45, n°1, 1990. pp. 55-64

Acute and chronic effects of Rhaponticum carthamoides and Rhodiola rosea extracts supplementation coupled to resistance exercise on muscle protein synthesis and mechanical power in rats

International audienceBackground: Owing to its strength-building and adaptogenic properties, Rhaponticum carthamoides (Rha) has been commonly used by elite Soviet and Russian athletes. Rhodiola rosea (Rho) is known to reduce physical and mental fatigue and improve endurance performance. However, the association of these two nutritional supplements with resistance exercise performance has never been tested. Resistance exercise is still the best way to stimulate protein synthesis and induce chronic muscle adaptations. The aim of this study was to investigate the acute and chronic effects of resistance exercise coupled with Rha and Rho supplementation on protein synthesis, muscle phenotype, and physical performance. Methods: For the acute study, fifty-six rats were assigned to either a trained control group or one of the groups treated with specific doses of Rha and/or Rho. Each rats performed a single bout of climbing resistance exercise. The supplements were administered immediately after exercise by oral gavage. Protein synthesis was measured via puromycin incorporation. For the chronic study, forty rats were assigned to either the control group or one of the groups treated with doses adjusted from the acute study results. The rats were trained five times per week for 4 weeks with the same bout of climbing resistance exercise with additionals loads. Rha + Rho supplement was administered immediately after each training by oral gavage. Results: The findings of the acute study indicated that Rha and Rha + Rho supplementation after resistance exercise stimulated protein synthesis more than resistance exercise alone (p < 0.05). After 4 weeks of training, the mean power performance was increased in the Rha + Rho and Rha-alone groups (p < 0.05) without any significant supplementation effect on muscle weight or fiber cross-sectional area. A tendency towards an increase in type I/ type II fiber ratio was observed in Rha/Rho-treated groups compared to that in the trained control group. Conclusion: Rhodiola and Rhaponticum supplementation after resistance exercise could synergistically improve protein synthesis, muscle phenotype and physical performance