Manioc : Portail | resultats 1 - 20 pour la recherche: Russo, Adelaide

Éditeur(s) : HAL CCSD Springer Verlag
Résumé : International audience
Ecosystems are commonly affected by natural, episodic disturbances that can abruptly and drastically alter communities. Although it has been shown that resilient ecosystems can eventually recover to pre-disturbed states, the extent to which communities in early stages of recovery could be affected by multiple anthropogenic stressors is poorly understood. Pervasive and rising anthropogenic stressors in coastal marine systems that could interactively affect the recovery of these systems following natural disturbances include high sedimentation, nutrient enrichment, and overfishing. Using a 6-month field experiment, we examined the effects of all combinations of these three stressors on key functional groups in the benthic community growing on simulated, post-disturbance reef patches within a system recovering from large-scale natural disturbances (corallivorous seastar outbreak and cyclone). Our study revealed that sedimentation, nutrient enrichment, and overfishing (simulated using exclusion cages) interactively affected coral survival and algal growth, with taxon-specific effects at multiple scales. First, our treatments affected corals and algae differently, with sedimentation being more detrimental to macroalgal growth but less detrimental to coral (Porites rus) survival in caged plots, driving significant interactions between sedimentation and caging for both taxa. We also observed distinct responses between coral species and between algal functional groups, with the most extensive responses from algal turf biomass, for which sedimentation suppressed the synergistic (positive) combined effect of nutrient enrichment and caging. Our findings suggest that different combinations of ubiquitous anthropogenic stressors, related to either sea- or land-based activities, interactively influence community recovery from disturbance and may alter species compositions in the resulting community. Our findings further suggest that anthropogenic stressors could promote further degradation of coral reefs following natural disturbances by inhibiting recovery to coral-dominated states that provide vital ecosystem services to coastal populations worldwide.
ISSN: 0722-4028

hal-01430977
https://hal-univ-perp.archives-ouvertes.fr/hal-01430977
DOI : 10.1007/s00338-016-1489-x

| Plus

L'abolitioniste français
Auteur(s) : Société française pour l'abolition de l'esclavage
Année de publication :

| Plus

Cinq semaines à travers la forêt Guyanaise
Auteur(s) : Quris, Bernard
Année de publication :

| Plus

Géographie complète et universelle : illustrée de 50 gravures, 8 cartes, 5 planches et du portrait de l'auteur. Tome quatrième
Auteur(s) : Malte-Brun, Conrad (1775-1826)
Auteurs secondaires : Malte-Brun, Victor-Adolphe (1816-1889)
Année de publication :

| Plus

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

| Plus