Éditeur(s) : HAL CCSD Pacific-credo Publications
Résumé : International audience
Les sciences humaines et sociales dans le Pacifique Sud, terrain questions et méthodes

ISBN : 978-2-9537485-2-9
hal-01342961
https://hal-univ-perp.archives-ouvertes.fr/hal-01342961

Éditeur(s) : HAL CCSD Elsevier
Résumé : SUBSURF
Statistical sequential analysis was performed on a series of sediment cores collected from the Têt prodelta in the Gulf of Lions, northwestern Mediterranean Sea, between October 2003 and October 2004. Seabed changes during that period were correlated to hydrodynamic conditions (waves and currents) and river discharge. Low sediment supply prevents full preservation of new sediment strata on this low-accumulation prodelta located on a microtidal, storm-dominated inner shelf. Severe meteorological events caused a rapid succession of erosion and deposition phases. For example, the December 2003 flood and storm produced a flood layer deposit that persisted for 2 months with only slight transformations due to early diagenesis and/or bioturbation, until a new storm event eroded this layer. A typical sedimentary sequence was observed for the secular deposits composed of a 10-cm-thick sandy layer overlaying siltyclayey layers. These characteristic features were used to analyse the last millennia sedimentary record of the Têt prodelta. The low preservation of freshly deposited sediments and variable sedimentation rates during the last millennia period yield a sedimentary sequence formed by the outcropping of muddy prodeltaic units intersected by heterogeneous siltysandy units similar to those formed under present day hydrodynamic conditions. No flood layer was found related to catastrophic flooding of the last century in the sedimentary record. The Little Ice Age ( 1550–1850 AD) probably favoured the formation of a well-developed muddy prodelta in the mouth of the Têt River. Later on, the decrease of sediment supply by rivers due to climate change and/or human activities (damming, irrigation), and the increase of the number of high-energy storms reaching the coast, induced a coarsening of the top sediment layer on this prodelta. This modern change of the substrate is also observed in the composition of benthic biota found in the substrate
ISSN: 0025-3227

hal-00407662
https://hal.archives-ouvertes.fr/hal-00407662
DOI : 10.1016/j.margeo.2007.04.009

Éditeur(s) : HAL CCSD National Academy of Sciences
Résumé : International audience
Diatoms (Bacillariophyta) constitute one of the most diverse and ecologically important groups of phytoplankton. They are considered to be particularly important in nutrient-rich coastal ecosystems and at high latitudes, but considerably less so in the oligotrophic open ocean. The Tara Oceans circumnavigation collected samples from a wide range of oceanic regions using a standardized sampling procedure. Here, a total of similar to 12 million diatom V9-18S ribosomal DNA (rDNA) ribotypes, derived from 293 size-fractionated plankton communities collected at 46 sampling sites across the global ocean euphotic zone, have been analyzed to explore diatom global diversity and community composition. We provide a new estimate of diversity of marine planktonic diatoms at 4,748 operational taxonomic units (OTUs). Based on the total assigned ribotypes, Chaetoceros was the most abundant and diverse genus, followed by Fragilariopsis, Thalassiosira, and Corethron. We found only a few cosmopolitan ribotypes displaying an even distribution across stations and high abundance, many of which could not be assigned with confidence to any known genus. Three distinct communities from South Pacific, Mediterranean, and Southern Ocean waters were identified that share a substantial percentage of ribotypes within them. Sudden drops in diversity were observed at Cape Agulhas, which separates the Indian and Atlantic Oceans, and across the Drake Passage between the Atlantic and Southern Oceans, indicating the importance of these ocean circulation choke points in constraining diatom distribution and diversity. We also observed high diatom diversity in the open ocean, suggesting that diatoms may be more relevant in these oceanic systems than generally considered.
ISSN: 0027-8424

hal-01545320
https://hal.archives-ouvertes.fr/hal-01545320
DOI : 10.1073/pnas.1509523113

Éditeur(s) : HAL CCSD
Résumé : International audience
Chronic obstructive pulmonary disease (COPD) is the chronic respiratory disease with the most important burden on public health in terms of morbidity, mortality and health costs. For patients, COPD is a major source of disability because of dyspnea, restriction in daily activities, exacerbation, risk of chronic respiratory failure and extra-respiratory systemic organ disorders. The previous French Language Respiratory Society (SPLF) guidelines on COPD exacerbations were published in 2003. Using the GRADE methodology, the present document reviews the current knowledge on COPD exacerbation through 4 specific outlines: (1) epidemiology, (2) clinical evaluation, (3) therapeutic management and (4) prevention. Specific aspects of outpatients and inpatients care are discussed, especially regarding assessment of exacerbation severity and pharmacological approach.
Revue Des Maladies Respiratoires

hal-01560287
https://hal-univ-rennes1.archives-ouvertes.fr/hal-01560287
DOI : 10.1016/j.rmr.2017.03.034
PUBMED : 28552256

Éditeur(s) : Gauthier-Villars
Oceanologica Acta (0399-1784) (Gauthier-Villars), 1982 , Vol. 5 , N. 4 , P. 481-491

Droits : info:eu-repo/semantics/openAccess
http://archimer.ifremer.fr/doc/00121/23188/21033.pdf
http://archimer.ifremer.fr/doc/00121/23188/