Éditeur(s) : HAL CCSD Elsevier
Résumé : International audience
Thermal acclimation drastically alters thermotolerance of ectotherms, but the mechanisms determining this plastic response are not fully understood. The present study investigates the proteomic response (2D-DIGE) of adult Drosophila melanogaster acclimated at 11, 25 or 31 C. As expected 11 C-acclimation improved cold tolerance and 31 C-acclimation improved heat tolerance. We hypothesized that the marked organismal responses to acclimation could be detected at the proteomic level assuming that changes in the abundance of specific proteins are linked to the physiological changes underlying the phenotypic response. The 31 C-acclimated flies displayed a particular divergent proteomic profile where molecular chaperones made up a large number of the proteins that were modulated during heat acclimation. Many other proteins showed significant modulation during acclimation including proteins involved in iron ion and cell redox homeostasis, carbohydrate and energy metabolism, chromatin remodeling and translation, and contractile machinery. Interestingly the changes in protein abundance were often unrelated to transcriptional activity of the genes coding for the proteins, except for the most strongly expressed proteins (e.g. Hsp70). The 11 C-acclimation evoked weak proteomic response despite the marked effect on the organismal phenotype. Thus the acquired cold tolerance observed here may involve regulatory process such as posttranslational regulation rather than de novo protein synthesis.
ISSN: 0965-1748

hal-00826939
https://hal.archives-ouvertes.fr/hal-00826939
DOI : 10.1016/j.ibmb.2013.01.006
PUBMED : 23416132

Éditeur(s) : Gauthier-Villars
Résumé : This review addresses the problem of recently introduced plants in the Mediterranean in order to analyse their vectors, the dispersal processes and the possible ecological and economic consequences. Ninety-five cases (94 macroscopic algae and one seagrass) are listed and discussed. Three major routes of access into the Mediterranean are indicated: shipping, the Suez canal and aqua-culture. The recent introduction of Caulerpa taxifolia along our coasts has called attention to a new potential source: aquaria. Among the successful acclimatizations, cold-temperate Pacific and Atlantic species remain confined to the north of the Mediterranean (Gulf of Lions, Adriatic), whereas some tropical or sub-tropical plants colonize large areas. Some introduced algae proliferate to the detriment of the indigenous Mediterranean vegetation. In contrast with some terrestrial introductions, no population crash has been observed in the Mediterranean, although some notable fluctuations seem to occur in coastal lagoons. From an economic point of view, the two activities most affected by this phenomenon are aquaculture and fishing. With the gradual disappearance of European frontiers, the worldwide development of marine cultures and the multiplication of giant Seaworlds, the transfer of live marine organisms will become routine and the risk of new introductions will considerably increase in the Mediterranean. Only international legislation, established by the countries of the littoral, will be able to control these problems.
Oceanologica Acta (0399-1784) (Gauthier-Villars), 1994 , Vol. 17 , N. 1 , P. 1-23

Droits : info:eu-repo/semantics/openAccess
http://archimer.ifremer.fr/doc/00098/20879/18493.pdf
http://archimer.ifremer.fr/doc/00098/20879/

Éditeur(s) : Elsevier
Résumé : The long-term BIOZAIRE multidisciplinary deep-sea environmental program on the West Equatorial African margin organized in partnership between Ifremer and TOTAL aimed at characterizing the benthic community structure in relation with physical and chemical processes in a region of oil and gas interest. The morphology of the deep Congo submarine channel and the sedimentological structures of the deep-sea fan were established during the geological ZAIANGO project and helped to select study sites ranging from 350 to 4800 m water depth inside or near the channel and away from its influence. Ifremer conducted eight deep-sea cruises on board research vessels between 2000 and 2005. Standardized methods of sampling together with new technologies such as the ROV Victor 6000 and its associated instrumentation were used to investigate this poorly known continental margin. In addition to the study of sedimentary environments more or less influenced by turbidity events, the discovery of one of the largest cold seeps near the Congo channel and deep coral reefs extends our knowledge of the different habitats of this margin. This paper presents the background, objectives and major results of the BIOZAIRE Program. It highlights the work achieved in the 16 papers in this special issue. This synthesis paper describes the knowledge acquired at a regional and local scale of the Equatorial East Atlantic margin, and tackles new interdisciplinary questions to be answered in the various domains of physics, chemistry, taxonomy and ecology to better understand the deep-sea environment in the Gulf of Guinea.
Deep Sea Research Part II: Topical Studies in Oceanography (0967-0645) (Elsevier), 2009-11 , Vol. 56 , N. 23 , P. 2156-2168

Droits : 2009 Elsevier Ltd All rights reserved.
http://archimer.ifremer.fr/doc/2009/publication-7349.pdf
DOI:10.1016/j.dsr2.2009.04.015
http://archimer.ifremer.fr/doc/00000/7349/

Éditeur(s) : Public Library Science
Résumé : Like hydrothermal vents along oceanic ridges, cold seeps are patchy and isolated ecosystems along continental margins, extending from bathyal to abyssal depths. The Atlantic Equatorial Belt (AEB), from the Gulf of Mexico to the Gulf of Guinea, was one focus of the Census of Marine Life ChEss (Chemosynthetic Ecosystems) program to study biogeography of seep and vent fauna. We present a review and analysis of collections from five seep regions along the AEB: the Gulf of Mexico where extensive faunal sampling has been conducted from 400 to 3300m, the Barbados accretionary prism, the Blake ridge diapir, and in the Eastern Atlantic from the Congo and Gabon margins and the recently explored Nigeria margin. Of the 72 taxa identified at the species level, a total of 9 species or species complexes are identified as amphi-Atlantic. Similarity analyses based on both Bray Curtis and Hellinger distances among 9 faunal collections, and principal component analysis based on presence/absence of megafauna species at these sites, suggest that within the AEB seep megafauna community structure is influenced primarily by depth rather than by geographic distance. Depth segregation is observed between 1000 and 2000m, with the middle slope sites either grouped with those deeper than 2000m or with the shallower sites. The highest level of community similarity was found between the seeps of the Florida escarpment and Congo margin. In the western Atlantic, the highest degree of similarity is observed between the shallowest sites of the Barbados prism and of the Louisiana slope. The high number of amphi-atlantic cold-seep species that do not cluster according to biogeographic regions, and the importance of depth in structuring AEB cold-seep communities are the major conclusions of this study. The hydrothermal vent sites along the Mid Atlantic Ridge (MAR) did not appear as "stepping stones" for dispersal of the AEB seep fauna, however, the south MAR and off axis regions should be further explored to more fully test this hypothesis.
Plos One (1932-6203) (Public Library Science), 2010-08 , Vol. 5 , N. 8 , P. 1-11

Droits : © 2010 Olu et al.
http://archimer.ifremer.fr/doc/00011/12207/8975.pdf
DOI:10.1371/journal.pone.0011967
http://archimer.ifremer.fr/doc/00011/12207/

Éditeur(s) : Université des Antilles Études caribéennes
Résumé : This study explores weather perceptions, evaluations and behavior of holiday-tourists to the French Caribbean island of La Martinique. Herein, the importance of selected weather parameters for a ‘typical’ summer holiday, for the choice that was made in coming to Martinique and for planned activities is examined. 32 snapshot interviews were held in two brief time periods within a month. Results illustrated slight differences in climate preferences for respondents depending whether they come from a cold or from a warm climate country, that activity patterns seemed overall little influenced by changing weather conditions and that the experienced weather, which was marked by heavy rains in the first data collection period and by changeable weather in the second, appeared to take only a limited impact on return intentions. Albeit the limited possibility of a pilot study to produce valid and reliable findings, variables and factors which are critical to consider when examining weather perceptions and behaviors have been pointed out and presented in a conceptual model for further research.
Cette étude explore les perceptions et les évaluations des conditions météorologiques et les comportements des vacanciers sur l'île de la Martinique. A ce sujet, l´étude examine l'influence de certains paramètres météorologiques sélectionnés sur des vacances d'été «typiques», sur le choix de la destination Martinique et sur les activités envisagées sur lieu. 32 interviews instantanées ont eu lieu en deux courtes périodes de temps pendant un mois. Les résultats illustraient qu´il y avait de légères différences concernant les préférences climatiques selon que les répondants venaient d'un pays au climat froid ou chaud, que les schémas d'activité semblaient généralement peu influencés par les changements météorologiques et que le temps - marquées par de fortes pluies dans la première période de la collecte de données et par un temps variable dans la seconde période - semblait n´avoir qu´un impact limité sur les intentions à revenir à la Martinique. Bien que l´étude pilote n´ait que des possibilités limitées de fournir des résultats valides et fiables, elle identifie les variables et les facteurs qui sont essentiels à considérer lors d´un projet de recherche qui examine la perception des conditions météorologiques par les touristes et les comportements qui en résultent. Ces facteurs sont présentés dans un modèle conceptuel.
Martinique

Droits : info:eu-repo/semantics/openAccess
urn:doi:10.4000/etudescaribeennes.5323
http://journals.openedition.org/etudescaribeennes/5323

Éditeur(s) : HAL CCSD Inter-Research
Résumé : International audience
The effects of global change are particularly serious in areas where range shiftsof species are physically constrained such as the Ligurian Sea, which is one ofthe coldest sectors of the Mediterranean. In this basin, historical informationon water temperature (from the sea surface down to 75 m depth) dates backto the 1950s. Early studies also recorded warm-water species occurrence.Thanks to these data we provide the first detailed characterization of watertemperature variation from 1958 up to 2010 in the layer 0–75 m depth. Wecoupled this analysis with the available information on rocky reef epibenthiccommunities (literature review from 1955 to 1964 and field data from 1980 to2010). The analysis of water temperature revealed several patterns of variation:a cooling phase from 1958 to 1980, a phase of rapid warming from 1980 to1990 and a phase of slower warming from 1990 to 2010. Inter-annual variationin temperature increased over the entire period for the water layer down to20 m. Warm-water native and alien species richness increased during thewarming phases. Literature estimates suggest a decrease in warm-water nativespecies richness during the cooling phase. The analysis of quantitative data collectedin the early 1990s and late 2000s indicated a decrease in the cover ofwarm-water native species on shallow rocky reefs and an increase in deeperwaters. We argue that increased inter-annual variation in water temperaturemay disadvantage native warm-water species in shallow waters. Our resultsindicate that the effect of temperature rises in cold, constrained basins may bemore complex than the simple prediction of species changing their geographicalrange according to their thermal limits.
Marine Ecology Progress Series

hal-01239259
https://hal-univ-perp.archives-ouvertes.fr/hal-01239259
DOI : 10.1111/maec.12277

Éditeur(s) : HAL CCSD Elsevier
Résumé : International audience
Transport of liquid and gaseous hydrocarbons through focused fluid flow systems is a widespread process in continental margins and sedimentary basins, which is gaining increased attention in the assessment of geohazards, environment conservation, and securing fossil energy resources. Studying the abundance, distribution and drivers for this process is crucial for understanding its role in 1) the dynamics of gas hydrate accumulation and destabilization, 2) submarine slope stability and related tsunamis, 3) the plethora of chemosynthetic benthic ecosystems that develop in deep seep sites, and 4) the input of greenhouse gases (e.g. methane) into the ocean/atmosphere system, which may influence the atmospheric carbon budget and Earth's paleo- and present climate. New ocean exploration tools provide ever more data and improve our understanding of these systems. However, the subject still suffers from a lack of interdisciplinary knowledge dissemination. The ongoing international debate about the timing and the processes that control fluid expulsion in sedimentary basins is fuelled by their implications for structural and petroleum geology. Because fluids expelled at cold seeps originate at depth they represent open windows into the underlying petroleum systems and are valuable indicators for the reservoir systems. They may also help in deciphering past and predicting future climate change because worldwide release of large amounts of fluids may have an impact on the chemistry of the ocean and atmosphere.
ISSN: 0025-3227

hal-00772472
https://hal.archives-ouvertes.fr/hal-00772472
DOI : 10.1016/j.margeo.2012.10.012

Éditeur(s) : Elsevier
Résumé : Deep-sea bivalves of the subfamily Bathymodiolinae (family Mytilidae) are very widespread and form dense beds in reduced environments such as hydrothermal vents and cold seeps. Bathymodiolus mussels recently discovered on African cold seeps strangely resemble Gulf of Mexico and Barbados seep species. This raises intriguing questions regarding their taxonomic relationships and their dispersal capabilities across the Atlantic equatorial belt. The morphological study of the shell and soft parts of mussels from either sites of the Atlantic shows that they form two distinct groups: the Bathymodiolus boomerang group (also including Bathymodiolus heckerae and a species from Africa), and the Bathymodiolus childressi group (also including Bathymodiolus mauritanicus and one species from Barbados). Phylogenetic relationships inferred from the nucleotide sequences of the ribosomal DNA internal transcribed spacer (ITS-2) and mitochondrial cytochrome c oxidase subunit I (COI) confirmed morphological analyses and the existence of two amphi-Atlantic complexes of species. Both ITS2 and COI phylogenies indicate almost no difference between the two eastern Atlantic seep mussels (Bathymodiolus sp. A and B. mauritanicus) and their western Atlantic counterparts (B. boomerang and Bathymodiolus sp. B; Barbados Prism cold seeps). In the B. boomerang complex, B. heckerae seems to differ from the Barbados and the African species, whereas these latter two are not distinguishable. In the B. childressi complex, relationships are less clear and do not support the description of new species from the Barbados. Past and present-day connections across the Atlantic are discussed in the light of both larval dispersal capabilities of the mussels and the equatorial Atlantic circulation to appreciate whether these species could represent true amphi-Atlantic species.
Deep Sea Research Part I: Oceanographic Research Papers (0967-0637) (Elsevier), 2007-11 , Vol. 54 , N. 11 , P. 1890-1911

Droits : 2007 Elsevier Ltd All rights reserved.
http://archimer.ifremer.fr/doc/2007/publication-4064.pdf
DOI:10.1016/j.dsr.2007.07.004
http://archimer.ifremer.fr/doc/00000/4064/

Éditeur(s) : Copernicus Gesellschaft Mbh
Résumé : Deep-sea bivalves found at hydrothermal vents, cold seeps and organic falls are sustained by chemosynthetic bacteria which ensure part or all of their carbon nutrition. These symbioses are of prime importance for the functioning of the ecosystems. Similar symbioses occur in other bivalve species living in shallow and coastal reduced habitats worldwide. In recent years, several deep-sea species have been investigated from continental margins around Europe, West Africa, East America, the Gulf of Mexico, and from hydrothermal vents on the Mid-Atlantic Ridge. In parallel, numerous more easily accessible shallow marine species were studied. We here provide a summary of the current knowledge available on chemosymbiotic bivalves in the area ranging west-to-east from the Gulf of Mexico to Marmara Sea, and north-to-south from the Arctic to the Gulf of Guinea. Characteristics of symbioses in 51 species from the area are summarized for each of the five bivalve families documented to harbor chemosynthetic symbionts (Mytilidae, Vesicomyidae, Solemyidae, Thyasiridae and Lucinidae), and compared among families with special emphasis on ecology, life cycle, and connectivity. Chemosynthetic symbioses are a major adaptation to ecosystems and habitats exposed to reducing conditions, yet relatively little is known regarding their diversity and functioning apart from a few "model species" on which effort has focused over the last 30 yr. In the context of increasing concern about biodiversity and ecosystems, and increasing anthropogenic pressure on Oceans, we advocate for a better assessment of bivalve symbioses diversity in order to evaluate the capacities of these remarkable ecological and evolutionary units to withstand environmental change
Biogeosciences (1726-4170) (Copernicus Gesellschaft Mbh), 2013 , Vol. 10 , N. 5 , P. 3241-3267

Droits : Author(s) 2012. CC Attribution 3.0 License.
http://archimer.ifremer.fr/doc/00133/24417/22431.pdf
DOI:10.5194/bg-10-3241-2013
http://archimer.ifremer.fr/doc/00133/24417/

Éditeur(s) : Université de Bretagne Occidentale
Résumé : The major objectives of this thesis were to study the structure, functioning and dynamics of different faunal assemblages associated with cold seep ecosystems in the eastern Mediterranean Sea. We focused our study on three main sites: the Marmara Sea, the Mediterranean ridge and the Nile deep sea fan. This thesis aims at determining the environmental signature of Mediterranean sites and the characteristics of the associated fauna at European and global scales. The specific objectives were to (1) determine the composition, diversity, density, biomass of invertebrate assemblages, (2) characterize biogeochemical conditions within different microhabitats in the vicinity of organisms, (3) to define the trophic relationships amongst seep fauna using stable isotope analyses (collaboration) and lastly, (4) to compare the spatial distribution and assemblage characteristics at different spatial scales (local, structure-scale, regional). The results show that (1) the Napoli mud volcano is the richest structure in terms of numbers of taxa while the Nile deep-sea fan sites need additional sampling, (2) a high variability is observed both between the different microhabitats but also within a single microhabitat, (3) the methane and oxygen gradients as well as substratum type are the main structuring factors explaining the distribution of the fauna and (4) the characteristics of the microhabitats, rather than the study area, influence the structure of benthic communities associated with Mediterranean cold seeps.
Les objectifs principaux de cette thèse sont d’étudier la structure, le fonctionnement et la dynamique de différents assemblages de faune associée aux émissions de fluides froids de Méditerranée orientale. Trois principaux sites ont été étudiés : la mer de Marmara, la ride méditerranéenne et le delta profond du Nil. Cette thèse tente de déterminer la « signature environnementale » des sites méditerranéens et les caractéristiques de la faune qui y est associée dans un contexte de marges européennes et mondiale. Les objectifs spécifiques sont (1) de déterminer la composition, la diversité, la densité et la biomasse des assemblages d'invertébrés ; (2) de caractériser les conditions biogéochimiques au sein des différents microhabitats à proximité des organismes; (3) de caractériser les relations trophiques sur les différents assemblages de faune par une approche isotopique (en collaboration) et finalement, (4) de comparer la distribution spatiale et les caractéristiques des assemblages à différentes échelles spatiales (locale, à l’échelle d’une structure géologique, régionale). Les résultats montrent que : (1) le volcan de boue Napoli est le site le plus riche en taxons alors que les sites du delta du Nil nécessiteraient un échantillonnage plus approfondi ; (2) il existe une grande variabilité entre les microhabitats ainsi qu’au sein d’un même microhabitat ; (3) les gradients en méthane, en oxygène ainsi que la nature du substrat sont les principaux facteurs abiotiques expliquant la distribution de la faune, (4) les caractéristiques des microhabitats, plutôt que la zone d’étude, influencent la structure des communautés benthiques associées aux écosystèmes de fluides froids méditerranéens.

Droits : 2010 The Author, UBO
http://archimer.ifremer.fr/doc/00020/13138/10178.pdf
http://archimer.ifremer.fr/doc/00020/13138/

Éditeur(s) : Université de La Rochelle
Résumé : Shrimp aquaculture in New Caledonia is a developing industry, exclusively based on the species Litopenaeus stylirostris. However, it is subject to mortalities during grow out as observed all over the world. Since 1993, shrimp reared during the cold period are affected by a disease named "syndrome 93". As a consequence, the whole industry has become seasonal and produces essentially during the warm season. The climatic conditions during the periods of transition between the two main seasons could be responsible for an environmental stress and the origin reason for mortality outbreaks. Stocking density is the main risk factor. It increases the probability of the appearance and development of the epizooty in the pond. The "Summer Syndrome", a septicemic vibriosis caused by Vibrio nigripulchritudo, was identified for the first time in December 1997 in an intensive shrimp farm (DF). It has become enzootic ever since and is expressed after 50d of rearing. Since 2003, two others farms located near DF have developed the disease. As a consequence, the summer syndrome is considered to be a potential threat for all the industry. Between 1991 and 2005, the increase of feed input and nitrogen levels in feed has led to a significant increase in the growth rate over the years in the farms affected by the disease. In consequence, an early eutrophication of the water is observed, which is concomitant with the beginning of the mortality outbreaks. An early eutrophication and the virulence level of the pathogen are considered as the main risk factors of the disease. Factors may act synergistically to explain the summer syndrome. As part of a multidisciplinary approach (pathology – physiology – environment), two high-frequency surveys were carried out to analyse the pond ecosystem. Since the feed quantity increases with the biomass of shrimp, the eutrophication level of the pond ecosystem will also tend to increase with the duration of rearing. During the first part of the rearing, the abundance of each picoplankton type is exceptionally high and picophytoplankton dominated the autotrophic compartment. The nanophytoplankton dominated the second part of the rearing and was more unstable. The shift from pico to nanophytoplankton could be considered as an environmental stress and was observed in relation to the beginning of the mortalities, whatever the disease. Shift intensity could play a role by inducing directly or indirectly a stress for shrimp and/or a growth and/or virulence factors of the pathogen. Results from sediment studies show that mortality was best characterized by TAN concentration in pore water and even more when the TAN concentration was high. TAN and pH are potential stress factors for shrimp reared in ponds affected by these diseases.
L'aquaculture mondiale de crevettes est un secteur à très forte croissance. Toutefois, les problèmes liés aux maladies dans les élevages ne cessent d'augmenter depuis 1980. Au cours du développement de la filière de Nouvelle-Calédonie, deux épisodes saisonniers de mortalités associées à la présence de Vibrio pathogènes sont apparus et ont fortement perturbé les techniques et les schémas de production. Les premières mortalités hivernales, décrites sous le nom de « syndrome 93 » ont été observées en mai 1993. Elles ont affecté depuis tous les élevages de saison froide de toutes les fermes de production. Les conditions climatiques pendant les périodes de transitions entre les deux principales saisons caractérisant le climat de la Nouvelle-Calédonie, seraient responsables d'un stress environnemental à l'origine du déclenchement du syndrome 93. La densité initiale d'ensemencement, apparaît comme le principal facteur de risque, augmentant la probabilité d'apparition de la maladie et l'ampleur de ses effets. Le « syndrome d'été » a été identifié pour la première fois en 1997 dans une ferme pratiquant une production intensive. Il s'est déclaré depuis 2003 dans deux autres fermes géographiquement proches. Les mortalités apparaissent 58 jours en moyenne après l'ensemencement des post-larves dans les bassins. La recherche d'une croissance maximale des animaux a induit, avec les années, une intensification progressive du système caractérisée par une augmentation de la quantité d'aliment distribuée. L'examen des données historiques fait apparaître une eutrophisation du milieu de plus en plus précoce concomitante au déclenchement des mortalités. En l'état actuel de nos connaissances, cette évolution précoce de l'écosystème en présence de façon récurrente de la souche hautement pathogène du Vibrio incriminé et à une période où la fréquence des mues des crevettes est élevée, constitue le principal facteur de risque de la maladie. Avec l'apport croissant en aliment, la colonne d'eau évolue vers une autotrophie croissante alors que le sédiment devient de plus en plus hétérotrophe au fur et à mesure que l'élevage progresse. Au cours du processus d'eutrophisation, le compartiment autotrophe montre une succession de deux assemblages. Le picophytoplancton domine sur la première partie de l'élevage et laisse place à du nanophytoplancton en seconde partie. Cette phase de transition, concomitante à l'apparition des mortalités quel que soit le syndrome, caractérise un stress environnemental dont l'intensité pourrait favoriser ou non le déclenchement des mortalités. Les suivis de différents indicateurs dans les sédiments - pH, potentiel d'oxydoréduction et concentration en ammoniaque dans l'eau interstitielle – indiquent dans les bassins déclarant les épizooties des conditions qui ont été définies expérimentalement comme potentiellement plus stressantes pour les animaux.

Droits : info:eu-repo/semantics/openAccess
http://archimer.ifremer.fr/doc/2007/these-2643.pdf
http://archimer.ifremer.fr/doc/00000/2643/

Éditeur(s) : HAL CCSD
Résumé : International audience
BACKGROUND: The aim of this systematic review was to evaluate and compare the pros and cons of using living donors or brain-dead donors in uterus transplantation programs, 2 years after the first worldwide live birth after uterus transplantation. METHODS: The Medline database and the Central Cochrane Library were used to locate uterine transplantation studies carried out in human or nonhuman primates. All types of articles (case reports, original studies, meta-analyses, reviews) in English or French were considered for inclusion. RESULTS: Overall, 92 articles were screened and 44 were retained for review. Proof of concept for human uterine transplantation was demonstrated in 2014 with a living donor. Compared with a brain-dead donor strategy, a living donor strategy offers greater possibilities for planning surgery and also decreases cold ischemia time, potentially translating into a higher success rate. However, this approach poses ethical problems, given that the donor is exposed to surgery risks but does not derive any direct benefit. A brain-dead donor strategy is more acceptable from an ethical viewpoint, but its feasibility is currently unproven, potentially owing to a lack of compatible donors, and is associated with a longer cold ischemia time and a potentially higher rejection rate. CONCLUSIONS: The systematic review demonstrates that uterine transplantation is a major surgical innovation for the treatment of absolute uterine factor infertility. Living and brain-dead donor strategies are not mutually exclusive and, in view of the current scarcity of uterine grafts and the anticipated future rise in demand, both will probably be necessary.
Transplantation

hal-01447062
https://hal-univ-rennes1.archives-ouvertes.fr/hal-01447062
DOI : 10.1097/TP.0000000000001481
PUBMED : 27607535

Éditeur(s) : HAL CCSD Elsevier
Résumé : International audience
This study presents the geochemical composition of superficial sediment under oxic and suboxic bottom water conditions along the Chilean continental margin (SE Pacific), where evidence for benthic chemosynthetic activity associated with diffuse seeping of chemically reduced fluids has been reported. The exploration was carried out at: (1) the Chilean Triple Junction (CTJ), at a water depth of ∼2900 m, with the additional indication of hydrothermal activity near a methane-rich cold-seep area (46°S) (German et al., 2010); and (2) the El Quisco methane seep site (EQSS), at ∼340 m water depth (33°S) (Melo et al., 2007; Krylova et al., 2014). While the deeper CTJ is located within an oxic environment (dissolved oxygen in the bottom waters: 164 μM), the shallower EQSS lies within a suboxic environment (dissolved oxygen in bottom water: 23 μM), located within the lower limit of the SE Pacific oxygen minimum zone (OMZ).Pore water from short cores was analyzed for dissolved major, minor, and trace elements (Cl, Na, Mg, K, Ca, Sr, Si, B, P, Ba, Pb, Mn, Fe, Cd, U, and Mo), δ13DIC, sulfide, sulfate, and methane. The solid sediment fraction was likewise analyzed for total organic carbon (TOC), metals, and redox potential. Elevated sediment temperatures were found in superficial sediments (5–13 °C) at the CTJ site, which could be due to warm fluids associated with the proximity of the ridge, where hydrothermal vents may occur. Reduced fluids were also present here, indicated by higher Mn fluxes toward the water column even in oxidized sediments (RPD > 8 cm), which contrasted with the lower fluxes in reduced sediments of the EQSS site (RPD ∼ 2 cm). 13C-depleted DIC, anomalously low pore water Cl (∼15 ppb), and low concentrations of other major elements may be the result of dilution by fluid seeping and precipitation of major elements, producing authigenic enrichment (Ca, Mg, Sr). The fluid could also: (a) be diluted by pure water produced during methane hydrate dissociation, as observed in other cold-seep areas; and (b) correspond to clay mineral dehydration, as reported in plate subduction systems. The reducing conditions established at the CTJ conduct the Cd enrichment at a similar magnitude of that seen at the shallower suboxic site (EQSS). Evidence of chimney or vent fauna was not observed. At the EQSS, higher TOC and total sulfide contents were consistent with enhanced deposition of organic matter and reducing conditions developed in the OMZ, favoring the authigenic enrichment of Cd, U and Pb. The geochemical evidence, based only on methane concentrations and δ13DIC, is insufficient to establish the presence of methane seeps, as previously reported.
ISSN: 0079-6611

hal-01412700
https://hal.archives-ouvertes.fr/hal-01412700
DOI : 10.1016/j.pocean.2016.09.002

Éditeur(s) : HAL CCSD Elsevier
Résumé : International audience
Seven male subjects volunteered to participate in an investigation of whether the diurnalincrease in core temperature influences the effects of pre-cooling or passivewarm-up on muscular power. Morning (07:00-09:00 h) and afternoon (17:00-19:00 h) evaluation of maximal power output during a cycling sprint was performed on different days in a control condition (room at 21.8 °C, 69% rh), after 30 min of pre-cooling in a cold bath (16 °C), or after 30 min of passivewarm-up in a hot bath (38 °C). Despite an equivalent increase from morning to afternoon in core temperature in all conditions (+0.4 °C, P < 0.05), power output displayed a diurnalincrease in control condition only. A local cooling or heating of the leg in a neutral environment blunted the diurnal variation in muscular power. Because pre-cooling decreases muscle power, force and velocity irrespective of time-of-day, athletes should strictly avoid any cooling before a sprint exercise. In summary, diurnal variation in muscle power output seems to be more influenced by muscle rather than core temperature.
ISSN: 1440-2440

hal-00706159
https://hal.univ-antilles.fr/hal-00706159
DOI : 10.1016/j.jsams.2007.09.008

Éditeur(s) : Elsevier
Résumé : We report on a multidisciplinary study of cold seeps explored in the Central Nile deep-sea fan of the Egyptian margin. Our approach combines in situ seafloor observation, geophysics, sedimentological data, measurement of bottom-water methane anomalies, pore-water and sediment geochemistry, and Th-230/U dating of authigenic carbonates. Two areas were investigated, which correspond to different sedimentary provinces. The lower slope, at similar to 2100 m water depth, indicates deformation of sediments by gravitational processes, exhibiting slope-parallel elongated ridges and seafloor depressions. In contrast, the middle slope, at similar to 1650 m water depth, exhibits a series of debris-flow deposits not remobilized by post-depositional gravity processes. Significant differences exist between fluid-escape structures from the two studied areas. At the lower slope, methane anomalies were detected in bottom-waters above the depressions, whereas the adjacent ridges show a frequent coverage of fractured carbonate pavements associated with chemosynthetic vent communities. Carbonate U/Th age dates (similar to 8 kyr BP), pore-water sulphate and solid phase sediment data suggest that seepage activity at those carbonate ridges has decreased over the recent past. In contrast, large (similar to 1 km(2)) carbonate-paved areas were discovered in the middle slope, with U/Th isotope evidence for ongoing carbonate precipitation during the Late Holocene (since similar to 5 kyr BP at least). Our results suggest that fluid venting is closely related to sediment deformation in the Central Nile margin. It is proposed that slope instability leads to focused fluid flow in the lower slope and exposure of 'fossil' carbonate ridges, whereas pervasive diffuse flow prevails at the unfailed middle slope.
Marine Geology (0025-3227) (Elsevier), 2009-06 , Vol. 261 , N. 1-4 , P. 92-104

Droits : 2009 Elsevier B.V. All rights reserved.
http://archimer.ifremer.fr/doc/2009/publication-6586.pdf
DOI:10.1016/j.margeo.2008.10.008
http://archimer.ifremer.fr/doc/00000/6586/

Éditeur(s) : Université des Antilles Études caribéennes
Résumé : For Norwegians the name of our country is based on a route - "the way to the North" - and this was not a built route but using of the coast-line itself. As long as the boats and ships were the main means of travel this coastal way - "Nor-way" - was the main communication basis for most people, and for transport of goods. But even in the interior of the country, water, namely rivers and lakes were the main structures for communication. The lakes were most efficient for transport during the cold winters, by sledges on the frozen surfaces.When new means of transport took over most of the traffic, however, sea, lakes and rivers in many ways became obstacles instead of means of communication (?). This gave the government and others new challenges. In the sailing period up to the end of the eighteen hundreds, boats and harbors were the investment focus and sailors were recruited in every community from the age of 15. This meant that in a remote area at the Arctic Circle there were plenty of people who have been sailing around most of the work and could easily be hosts of visitors.This paper is mostly focusing on "how to market and develop these beautiful coastal areas to travelers using either their own cars, bikes, boats or collective transport". What types of geographical units are suited for marketing and developing such areas and how might local producers of accommodation, food & beverages, crafts, activities and arts be included in such organizations. The main focus will be on the work of organization "Kystriksvegen Reiseliv AS" that have been working with these challenges for closed to two decades. What have their successes and obstacles been and how have they been able to operate a sustainable business on a long coastal route with many car ferries, small islands, fjords and mountains and more than twenty municipalities.
Pour les Norvégiens, le nom de notre pays est basé sur un itinéraire - «le chemin vers le Nord» - et ce n'était pas une route construite, mais qui repose sur la ligne de côte elle-même. Tant que les bateaux et les navires étaient le principal moyen de déplacement de cette façon côtière – "Nor-way" - était la base principale de communication pour la plupart des gens et pour le transport de marchandises, et même à l'intérieur du pays, l'eau, à savoir les rivières et les lacs étaient les principales structures de communication. Les lacs sont les plus efficaces pour le transport pendant les hivers froids, par traîneaux sur les surfaces gelées.Avec l’arrivée des nouveaux moyens de transport, la mer, les lacs et les rivières à bien des égards, sont devenus obstacles (?). Cela a donné de nouveaux défis au gouvernement. A l’époque de la voile jusqu'à la fin des dix-huit centaines, des bateaux et des ports ont été l'objet d'investissements et les marins ont été recrutés dans toutes les collectivités dès l’âge de 15 ans. Cela signifie que dans une région éloignée dans le cercle arctique, il y avait beaucoup de gens qui étaient navigateurs et pouvaient facilement être les hôtes de visiteurs.Ce document est principalement axé sur «la façon de commercialiser et de développer ces belles régions côtières de voyageurs qui utilisent soit leurs propres voitures, motos, bateaux ou de transports collectifs». Quels types d'unités géographiques sont adaptés pour la commercialisation et le développement de ces régions ? Comment les producteurs locaux d'hébergement, de nourriture et de boissons, d’artisanat, les activités et les arts sont inclus dans ces organisations ? L'accent principal sera mis sur le travail de l’organisation "Reiseliv AS Kystriksvegen" qui a travaillé sur ces défis de fermeture depuis deux décennies. Quelles ont été leurs réussites et obstacles, et comment ont-ils pu exploiter une entreprise durable sur une longue route côtière avec des car-ferries, de nombreuses petites îles, des fjords et des montagnes et plus d’une vingtaine de municipalités.
Norvège

Droits : info:eu-repo/semantics/openAccess
urn:doi:10.4000/etudescaribeennes.5286
http://journals.openedition.org/etudescaribeennes/5286

Éditeur(s) : HAL CCSD American Geophysical Union (AGU) AGU and the Geochemical Society
Résumé : International audience
To study how an impacting plume modifies the mantle lithosphere, we analyzed the microstructures and crystal preferred orientations (CPO) of 29 peridotites and 37 pyroxenites that sample the mantle root of the Ontong Java Plateau (OJP) from 60 to 120 km depth. The peridotites show a strong compositional variability, but homogeneous coarse granular to tabular microstructures, except for those equilibrated at the shallowest and deepest depths, which are porphyroclastic. All peridotites have clear olivine CPO, with dominant fiber-[010] patterns. Low intragranular misorientations and straight grain boundaries in olivine suggest that, above 100 km depth, annealing often followed deformation. Calculated density and P wave velocities of the peridotites decrease weakly with depth. S wave velocities decrease faster, resulting in increasing Vp/Vs ratio with depth. Calculated densities and seismic velocity profiles are consistent with those estimated for normal mantle compositions under a cold oceanic geotherm. Enrichment in pyroxenites may further increase seismic velocities. The calculated seismic properties cannot therefore explain the low S waves velocities predicted by Rayleigh wave tomography and ScS data in the mantle beneath the OJP. Calculated P and S waves anisotropy is variable (2–12%). It is higher on average in the deeper section of the lithosphere. Because olivine has dominantly [010]-fiber CPO patterns, if foliations are horizontal, vertically propagating S waves and Rayleigh waves will sample very weak anisotropy in the OJP mantle lithosphere. Moreover, if the orientation of the lineation changes with depth, the anisotropy-induced contrast in seismic properties might produce an intralithospheric reflector marking the stratification of the OJP mantle root.
ISSN: 1525-2027

hal-01116428
https://hal.archives-ouvertes.fr/hal-01116428
DOI : 10.1002/2014GC005452

Éditeur(s) : HAL CCSD Royal Society, The
Résumé : International audience
Bathymodiolin mussels occur at hydrothermal vents and cold seeps, where they thrive thanks to symbiotic associations with chemotrophic bacteria. Closely related genera Idas and Adipicola are associated with organic falls, ecosystems that have been suggested as potential evolutionary 'stepping stones' in the colonization of deeper and more sulphide-rich environments. Such a scenario should result from specializations to given environments from species with larger ecological niches. This study provides molecular-based evidence for the existence of two mussel species found both on sunken wood and bones. Each species specifically harbours one bacterial phylotype corresponding to thioautotrophic bacteria related to other bathymodiolin symbionts. Phylogenetic patterns between hosts and symbionts are partially congruent. However, active endocytosis and occurrences of minor symbiont lineages within species which are not their usual host suggest an environmental or horizontal rather than strictly vertical transmission of symbionts. Although the bacteria are close relatives, their localization is intracellular in one mussel species and extracellular in the other, suggesting that habitat choice is independent of the symbiont localization. The variation of bacterial densities in host tissues is related to the substrate on which specimens were sampled and could explain the abilities of host species to adapt to various substrates.
ISSN: 0950-1193

hal-00755293
https://hal.univ-antilles.fr/hal-00755293
DOI : 10.1098/rspb.2008.1101

Résumé : The MEDECO Leg 2 cruise followed the MEDECO Leg 1 cruise that had crossed the Mediterranean Sea from the west to the east to study benthic communities of the Var canyon, deep corals found on the Calabrian Margin and cold seep ecosystems of the Mediterranean Ridge. The main objective of the MEDECO Leg 2 cruise was to study and compare, using a multidisciplinary approach, the structure and dynamics of deep-sea ecosystems at various active cold seep sites from the Nile deep sea fan and the Calabrian Arc, in the Eastern Mediterranean sea. During MEDECO Legs 1 & 2, a multiscale strategy was promoted to integrate (1) a high resolution cartography of geological structures (km2 scale), (2) a detailed mapping, including video imagery, of smaller-scale areas (scale 100 to 300 m2), (3) the physical, chemical and sedimentary characteristics of the habitat (multiscale), (4) the structure and functioning of faunal communities, including microbes, in terms of composition, diversity and biomass (multiscale), (5) small scale studies of interactions between organisms and their environment (scale < m2), (6) detailed ecophysiological studies at the organism scale on invertebrates. The use of the ROV “Victor 6000” and of various equipments for in situ and ex situ observations and measurements has helped reaching our objectives. The MEDECO cruise represented the key-Mediterranean cruise of the HERMES project “Hotspot Ecosystem Research on the Margins of European Seas” (P.I. P. Weaver, NOC-Southampton). The cruise was organized to follow the objectives of the HERMES program to better understand the functioning of deep ecosystems of the continental margins aiming at obtaining: (1) the description and quantification of the natural drivers (geological, hydrological, chemical factors) that control the distribution of ecosystems on margins; (2) the characterization and quantification of biodiversity, from bacteria to megafauna, as well as the knowledge of ecosystem functioning; (3) the study of ecosystems dynamics including the biology/physiology of key-species. Specific objectives. Colonization experiments conducted in the frame of two European programs, Diwoo and Chemeco, have given the opportunity to recover the fauna installed in the devices deployed during the Bionil cruise (2006) and to deploy new ones at the same site located in the pockmark area of the central province of Nile deep sea fan.

Droits : 2008 Insu, Cnrs, Locean
http://archimer.ifremer.fr/doc/00134/24550/22583.pdf
http://archimer.ifremer.fr/doc/00134/24550/

Éditeur(s) : HAL CCSD Elsevier
Résumé : International audience
The analysis of 2D deep-seismic-reflection profiles across the slope and abyssal plain of the Angola oceanic basin reveals the existence of a significant and formerly unknown depocentre beneath the giant Cenozoic Congo deep-sea fan, between 7000 m and 9000 m depth, deposited directly onto the Aptian oceanic crust. The unit, which is up to 2.5 km thick and extends for more than 200 km basinwards of the Continent-Ocean boundary, is probably aged Albian-Turonian. Its radial fan-shaped depocentre is centred on the present-day Congo River outlet and contains at least 0.2 Mio km(3) of sediments. These observations and the results from flexural modelling indicate that (1) the location of the Congo River's outlet has remained fairly stable since the Late Cretaceous, and (2) the basal unit was indeed sourced by a palaeo-Congo River probably located nearby the present-day one. Thus, the Atlantic sedimentary system related to the exoreism of the Congo River is much older than previously thought. Thermal modelling indicates that the maturation history of this upper-Cretaceous deposits is highly influenced by the interaction between the initial high heat flow of the young oceanic crust and further increase in sediment supply due to the progradation of the overlying Tertiary deep-sea fan during the Miocene. Hence, despite low present-day heat-flow values, should the unit have source rock potential, its basal section may be currently generating hydrocarbons.;All in all, the results from our models also suggest that the interplay between an initially high heat flow and the further high sediment supply in areas of major river input, may be a key factor for the thermal maturation of potential source rocks deposited onto a present-day "cold" oceanic crust.
ISSN: 0264-8172

hal-00475541
https://hal.archives-ouvertes.fr/hal-00475541
DOI : 10.1016/j.marpetgeo.2009.08.015