Manioc : Portail | resultats 1 - 20 pour la recherche: Ségura, Caroline

Éditeur(s) : HAL CCSD Wiley-Blackwell
Résumé : International audience
1. Our understanding of the contribution of interspecific interactions to functional diversity in nature lags behind our knowledge of spatial and temporal patterns. Although two-species mutualisms are found in all types of ecosystems, the study of their ecological influences on other community members has mostly been limited to third species, while their influence on entire communities remains largely unexplored. 2. We hypothesized that mutualistic interactions between two respective ant species and an epiphyte mediate the biological traits composition of entire invertebrate communities that use the same host plant, thereby affecting food webs and functional diversity at the community level. 3. Aechmea mertensii (Bromeliaceae) is both a phytotelm ('plant-held water') and an ant-garden epiphyte. We sampled 111 bromeliads (111 aquatic invertebrate communities) associated with either the ant Pachycondyla goeldii or Camponotus femoratus. The relationships between ants, bromeliads and invertebrate abundance data were examined using a redundancy analysis. Biological traits information for invertebrates was structured using a fuzzy-coding technique, and a co-inertia analysis between traits and abundance data was used to interpret functional differences in bromeliad ecosystems. 4. The vegetative traits of A. mertensii depended on seed dispersion by C. femoratus and P. goeldii along a gradient of local conditions. The ant partner selected sets of invertebrates with traits that were best adapted to the bromeliads' morphology, and so the composition of the biological traits of invertebrate phytotelm communities depends on the identity of the ant partner. Biological traits suggest a bottom-up control of community structure in C. fenaoratus-associated phytotelmata and a greater structuring role for predatory invertebrates in P. goeldii-associated plants. 5. This study presents new information showing that two-species mutualisms affect the functional diversity of a much wider range of organisms. Most biological systems form complex networks where nodes (e.g. species) are more or less closely linked to each other, either directly or indirectly, through intermediate nodes. Our observations provide community-level information about biological interactions and functional diversity, and perspectives for further observations intended to examine whether large-scale changes in interacting species/community structure over broad geographical and anthropogenic gradients affect ecosystem functions.
Functional Ecology

hal-01096909
https://hal-agroparistech.archives-ouvertes.fr/hal-01096909
DOI : 10.1111/j.1365-2435-2011.01863.x

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Abrégé de l'histoire générale des voyages, contenant ce qu'il y a de plus remarquable, de plus utile & de mieux avéré dans les pays où les voyageurs ont pénétré : les moeurs des habitans, la religion, les usages, arts & sciences, commerce, manufactures : enrichie de cartes géographiques & de figures. Tome treizième, [Amérique]
Auteur(s) : La Harpe, Jean François de (1739-1803)
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Annuaire de la vie martiniquaise : 1936
Auteur(s) : Sylvestre, Emile (1...-19.. ; fonctionnaire) Lotaut, Eustache
Auteurs secondaires : Eboué, Félix (1884-1944)
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Le livre d'or du négociant. Tome 1
Auteur(s) : Potel, Maurice (1866-19..)
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Almanach américain, ou Etat physique, politique, ecclésiastique et militaire de l'Amérique : ouvrage qui comprend les forces, la population, les loix, le commerce et l'administration de chaque province de cette partie du monde ; le tableau de ceux qui y figurent par leurs charges et par leurs dignités ; celui de la marine des peuples européens qui y ont possessions, et le nom des officiers qui sont employés dans cette partie de l'administration publique
Auteur(s) : Poncelin de la Roche-Tilhac, Jean-Charles (1746-1828)
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Le Brésil en 1889 : avec une carte de l'empire en chromolithographie
Auteur(s) : Santa Anna Nery, Frederico José de (1848-1901)
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Guidelines for the use and interpretation of assays for monitoring autophagy.
Auteur(s) : Klionsky, Daniel J Abdalla, Fabio C Abeliovich, Hagai Abraham, Robert T Acevedo-Arozena, Abraham Adeli, Khosrow Agholme, Lotta Agnello, Maria
Auteurs secondaires : Molecular and Cellular Biology ; University of Leuven Laboratoire d'Epigénétique et Cancer ; CNRS - Université Paris-Sud - Paris 11 (UP11) Department of Pharmacology ; Department of Pharmacology Immunobiologie des Cellules Dendritiques ; INSERM - Institut Pasteur de Paris Franche-Comté Électronique Mécanique, Thermique et Optique - Sciences et Technologies (FEMTO-ST) ; CNRS - Université de Franche-Comté - Université de Technologie de Belfort-Montbeliard - Ecole Nationale Supérieure de Mécanique et des Microtechniques Telethon Institute for Genetics and Medicine ; Telethon Institute Medical Genetics ; Federico II University Department of Molecular and Human Genetics ; Baylor College of Medicine

Éditeur(s) : HAL CCSD Landes Bioscience
Résumé : International audience
In 2008 we published the first set of guidelines for standardizing research in autophagy. Since then, research on this topic has continued to accelerate, and many new scientists have entered the field. Our knowledge base and relevant new technologies have also been expanding. Accordingly, it is important to update these guidelines for monitoring autophagy in different organisms. Various reviews have described the range of assays that have been used for this purpose. Nevertheless, there continues to be confusion regarding acceptable methods to measure autophagy, especially in multicellular eukaryotes. A key point that needs to be emphasized is that there is a difference between measurements that monitor the numbers or volume of autophagic elements (e.g., autophagosomes or autolysosomes) at any stage of the autophagic process vs. those that measure flux through the autophagy pathway (i.e., the complete process); thus, a block in macroautophagy that results in autophagosome accumulation needs to be differentiated from stimuli that result in increased autophagic activity, defined as increased autophagy induction coupled with increased delivery to, and degradation within, lysosomes (in most higher eukaryotes and some protists such as Dictyostelium) or the vacuole (in plants and fungi). In other words, it is especially important that investigators new to the field understand that the appearance of more autophagosomes does not necessarily equate with more autophagy. In fact, in many cases, autophagosomes accumulate because of a block in trafficking to lysosomes without a concomitant change in autophagosome biogenesis, whereas an increase in autolysosomes may reflect a reduction in degradative activity. Here, we present a set of guidelines for the selection and interpretation of methods for use by investigators who aim to examine macroautophagy and related processes, as well as for reviewers who need to provide realistic and reasonable critiques of papers that are focused on these processes. These guidelines are not meant to be a formulaic set of rules, because the appropriate assays depend in part on the question being asked and the system being used. In addition, we emphasize that no individual assay is guaranteed to be the most appropriate one in every situation, and we strongly recommend the use of multiple assays to monitor autophagy. In these guidelines, we consider these various methods of assessing autophagy and what information can, or cannot, be obtained from them. Finally, by discussing the merits and limits of particular autophagy assays, we hope to encourage technical innovation in the field.
Autophagy

hal-00735751
https://hal.archives-ouvertes.fr/hal-00735751
PUBMED : 22966490

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Recherches chronologiques et historiques sur l'origine et la propagation de la fièvre jaune dans les Antilles et sur la côte occidentale d'Afrique
Auteur(s) : Cornilliac, Jean Jacques Jules
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Du typhus d'Amérique ou fièvre jaune
Auteur(s) : Bally, François-Victor (1775-1866)
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