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Résumé: Les arbovirus sont des virus transmis à l'Homme et/ou à des animaux par des arthropodes hématophages. Ils sont importants en termes de santé publique mais également d'un point de vue économique. Au vu du nombre d'arbovirus déjà identifiés et de leur grande variabilité génétique, il est nécessaire, voire indispensable, d'avoir des outils ayant une grande flexibilité pour leur surveillance. La circulation des arbovirus au sein d'une population animale peut se démontrer par recherche directe du virus au sein de l'hôte et/ou du vecteur ou par recherche indirecte du virus en mettant en évidence une séroconversion chez l'hôte vertébré. Les virus ont des grandes capacités d'adaptation qui leur permettent d'émerger dans de nouvelles zones géographiques et/ou de franchir les barrières d'espèces. Au fil des décennies, la surveillance des arbovirus a considérablement évolué grâce à toutes les technologies innovantes qui ont vu le jour. Les objectifs de cette revue sont de faire l'état de l'art sur : (i) les outils classiques pour la recherche directe ou indirecte des arbovirus, (ii) les outils de nouvelle génération qui répondent au mieux aux attentes en termes de surveillance optimale des arbovirus et (iii) les axes d'amélioration pour la surveillance des arbovirus. Arboviruses are viruses transmitted to humans and/or animals by hematophagous arthropods. They have a significant economic and public health impact. Given the number of arboviruses already identified and their great genetic variability, it is essential to have highly flexible tools for their monitoring. Arbovirus circulation within animal populations can be demonstrated by direct and/or indirect screening of a specific virus within vertebrate hosts and/or arthropod vectors. Viruses have great adaptive capacities that enable them to emerge into new geographic areas and/or cross species barriers. Over the decades, arbovirus monitoring has considerably evolved due to innovations in detection technologies. The objectives of this review are to list and assess (i) the current tools for direct or indirect screening for arboviruses, (ii) the new generation tools that best meet expectations in terms of optimal arbovirus monitoring and (iii) the potentials for improved arbovirus monitoring. [ABSTRACT FROM AUTHOR]

To manage large wildlife, control proliferations or protect species, one needs to work on extensive territories and take the diversity of the geographical environment into account. This is defined by three main factors that are meaningful from both natural and social standpoints, i.e., density, accessibility and shape. Alone or combined, they offer new perspectives on the management of wild boar and wolf. Regarding wild boars, animal as well as human density, sometimes linked to the effects of shape or accessibility, accounts for the diversity of management methods applied in the different French régions. As for wolves, their perception of the environment as either friendly or non-friendly depends both on natural (trophic, intraspecific competition, topographic) factors and social factors (breeding conditions, legal status). Under the pressure of control culling adjusted to local situations, feelings change with increasing densities. The study of Spanish situations shows how wolf distribution is due to a combination of human density, natural preys and cattle farming and also to the relationships between hunters and livestock farmers. To conclude, we propose to include the density ratio between farmers and hunters in management parameters. We argue that the legal status of species should change when densities increase based on a département spatial scale. [ABSTRACT FROM AUTHOR]

The aim of sanitary qualification of farm animals is to implement collective strategies to control the spread of infectious diseases. More specifically, it seeks to establish objectively and accurately the status of an animal or animal population, which will be used for animal exchange and trading, with regard to a given infectious disease. The approach is based upon biological knowledge about the infectious agent including infection process and detection means. In addition, mathematical modelling, statistics and probability tools allow integrating these pieces of knowledge as well as taking into account uncertainty and the variability of biological parameters. Finally, Social and Human sciences, and particularly economics and sociology provide an understanding of stakes, social representations, and points of view of individuals and groups, in order to study the demand and acceptability of sanitary qualification for a given infectious disease. In this approach, each discipline contributes its own standpoint on the underlying question of risk. This interdisciplinary approach requires co-constructing the research topic and stepping beyond epistemological and cultural differences between disciplines. Furthermore, designing a qualification result from a collective social construction. It does not solely obey rationality based on science and regulation needs; it includes necessarily both scientific and common knowledge and is dependant upon various political decisions that can lead to consensus or contradiction. [ABSTRACT FROM AUTHOR]

Copyright of Biotechnologie, Agronomie, Societe et Environnement is the property of Les Presses Agronomiques de Gembloux and its content may not be copied or emailed to multiple sites or posted to a listserv without the copyright holder's express written permission. However, users may print, download, or email articles for individual use. This abstract may be abridged. No warranty is given about the accuracy of the copy. Users should refer to the original published version of the material for the full abstract. (Copyright applies to all Abstracts.)

Copyright of Éducation et Francophonie is the property of Association Canadienne d'Education de Langue Francaise (ACELF) and its content may not be copied or emailed to multiple sites or posted to a listserv without the copyright holder's express written permission. However, users may print, download, or email articles for individual use. This abstract may be abridged. No warranty is given about the accuracy of the copy. Users should refer to the original published version of the material for the full abstract. (Copyright applies to all Abstracts.)

The article offers information on ecologist as well as geneticist Maxime Lamotte's search for synthesis of ecology and evolution. It states that he gave major importance to quantitative methods for his ecological studies on various habitats in Mount Nimba and worked on Cepaea snails' natural population in France. It also discusses the importance of coevolution within ecosystems and the influence of ecological interaction on natural selection processes. It also notes that tansformations from human activities are the major evolutionary phenomenon of the time.

Abstract: The impact of sedimentary conditions on the settlement, growth, and morphology of primitive spatangoid sea urchins of the genus Toxaster from the Lower Cretaceous (Valanginian and Hauterivian of the Provencal platform) is analyzed. The analyses concern spatial and temporal patterns of variation. The spatial approach is based on six isochronous populations of Toxaster granosus kiliani (424 specimens in total) dated from the Verrucosum biozone, and distributed along a proximo-distal gradient. The temporal approach concerns a reference section (Carajuan) ranging from the Lower Valanginian to the Upper Hauterivian, and involving the species T. granosus kiliani and T. gibbus. Sedimentary environments have been characterized by a factorial analysis of five characteristics of facies. Sea urchin morphology has been described with seven measures allowing the computation of two angles (α and β), and of six shape indices analyzed through a principal components analyses. The spatial approach shows that the adult mean size (> 20 mm) increases distally, and that morphology changes significantly across localities. However, only variations in α and β are sequentially organized along the proximo-distal gradient (they correspond to a forward migration of the peristome and to an expansion of the plastronal area). The stratigraphic survey of facies variation along the 369 beds analyzed in Carajuan shows a clear change in sedimentary conditions: from unstable with bioclastic events (Valanginian), to homogeneous with a low content in bioclasts (Hauterivian). Most Toxaster specimens are concentrated in three stratigraphic units (Campylotoxus and Verrucosum biozones for T. granosus kiliani; Sayni biozone for T. gibbus), their abundance being related to the macrofaunal presence and diversity and to burrowing activity. The adult mean size is only significantly related to facies variation, for the T. granosus kiliani from the Verrucosum biozone, increasing with textural gradient and bioclastic content. Shape – facies relationships have been identified for T. granosus kiliani in both Campylotoxus and Verrucosum intervals. However, the morphological variables and facies characteristics involved differ between the two biozones. The synthesis of all significant relationships between size or shape and facies characteristics demonstrates that the response of Toxaster to environmental changes was limited, and varied in space as well as for the different periods of time considered. The only recurring impact of sedimentary changes involved sea urchin abundance, that is, their ability to settle. The low adaptive potential of Toxaster is discussed in the context of the early radiation of the Spatangoida. [Copyright &y& Elsevier]