Éditeur(s) : Elsevier
Résumé : This paper presents a survey of French Eastern English Channel fishers' observations of the past and current state of the marine ecosystem and their wishes for the future, as a first step towards formulating management objectives. Twenty-nine semi-directive interviews were carried out in June 2006 among fishers and shellfish farmers. Cognitive maps proved useful to formalise their experience and knowledge. Most interviewees mentioned a decrease of the resource in recent years and pointed out the presence of several problems, such as pollution, degradation of the ocean floor and harmful impacts of human activities, including fishing. The indicators used by the fishers as the basis to form their opinion were similar to those generally used by scientists for assessing the state of exploited marine populations and communities (average fish length, CPUE, fished biomass...); additional indicators were the timing and duration of fishing seasons. (c) 2008 Elsevier Ltd. All rights reserved.
Ocean & Coastal Management (0964-5691) (Elsevier), 2008-06 , Vol. 51 , N. 6 , P. 450-462

Droits : 2008 Elsevier Ltd All rights reserved.
http://archimer.ifremer.fr/doc/2008/publication-6134.pdf
DOI:10.1016/j.ocecoaman.2008.04.005
http://archimer.ifremer.fr/doc/00000/6134/

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) : HAL CCSD
Résumé : International audience
One of the most common tasks in the area of social network mining is the extraction of frequent patterns from social networks. Although traditional approaches have been mainly focused on subgraphs occurring frequently in a network or a set of networks, new approaches have attempted to exploit network structure and node properties in order to elicit new kinds of patterns. One of these news approaches is the extraction of conceptual links, a solution that combines both structure and node properties for providing knowledge on the groups of nodes the most connected in a social network. However, if the extraction of conceptual links offers a great potential in terms of knowledge discovery as well as network visualization, the search for these kinds of patterns remains a computationally intensive problem. Thus, the efficiency of the extraction processes highly depends on the efficiency of the underlying algorithm. In this paper, we focus on the extraction of maximal frequent conceptual links (MFCL) and we propose a hybrid algorithm that applies a filter on the nodes for reducing the search space to the most frequent groups of nodes. Although our solution potentially causes loss of some patterns, we demonstrate its efficiency by comparison with the MFCLMin algorithm. We investigate the potential loss of patterns, the gain on the runtime, and the gain on the number of comparisons.
IEEE International Conference on Research Challenges in Information Science
Paris, France

hal-00841699
https://hal.archives-ouvertes.fr/hal-00841699

Éditeur(s) : Université de la Rochelle
Résumé : In order to better understand the functioning of the Brouage intertidal mudflat (Marennes- Oléron Basin, France), its carbon-based trophic web has been modelled and analyzed. The foodweb building is based on the 4 step method of Inverse Analysis: 1) conceive an a priori model as the graph of compartments (nodes) between which exist fluxes of material (vertices). These vertices are the unknowns for the problem; 2) gather all the existing knowledge about the ecosystem and translate it into linear equations and inequalities involving the fluxes; 3) complete this set of data by common knowledge on the behaviour of the compartments and translate it into inequalities, 4) solve the obtained linear system under the parsimony principle to find a unique solution vector. The food-web analysis is based on. The first purpose of this work was a methodological one: inverse analysis method has been adapted to consider the seasonal and spatial variability of the temperate ecosystem: two seasons have been coupled in the computation and the area has been divided into three geographical zones along a cross-shore gradient. Hence, two types of physical exchanges are involved: the benthicpelagic ones and the advection ones. Statistical results can also be obtained by coupling Monte Carlo methods to Inverse Analysis. To study the obtained networks, new indices based on Markov Chains take delay into account in describing integrative transfers of material between compartments. This lets emerge the systems' properties that are not obvious at first sight and emphasizes the role of peculiar components. The second purpose was to apply such methods to the Brouage mudflat ecosystem in order to better understand its functioning. As the knowledge and methods evolve, various food webs were computed and analyzed with the help such indices and existing ones. Sensitivity analyses allow to point at the most crucial lacks of knowledge, which can orientate future field research. New data would improve the quality of the model in two ways: one the one hand, they would validate or invalidate the outcomes and on the other hand, they would give useful information to better constrain some of the black boxes and most uncertain fluxes, especially the advection and vertical flows. The main results of the study show a strongly seasonal system in which benthic and pelagic components are linked with intensity. The system is driven by its high local benthic primary production, but also depends on imports from the basin. Each of the 3 geographic zones has a peculiar functioning. The central zone corresponds to the classical description of European intertidal mudflats: very productive, it can feed the other regions. It is a production zone. The upper part is less productive but is fed by the middle one via the water column and can be exploited by shorebirds. It is a degradation zone (material is transformed for less qualitative). The lower part strongly depends on the basin imports for its functioning, as the cultivated bivalves act as a pump for pelagic material of which a great part is deposited under the cultivation structures (oyster racks or mussels "bouchots"). It is a transformation zone.
Un double objectif (méthodologique et appliqué) a été visé par une modélisation du réseau trophique de la vasière de Brouage (Bassin de Marennes Oléron, France) à l'aide de l'analyse inverse, et son étude à l'aide de l'analyse des réseaux. L'Analyse Inverse permet en effet de reconstruire l'ensemble du réseau à partir de données éparses, le problème du manque de données étant récurrent en Ecologie. Au plan méthodologique, l'analyse inverse a été adaptée à la prise en compte des caractères saisonnier et spatialement hétérogène d'un écosystème tempéré de zone intertidale : deux saisons ont ainsi été couplées et la vasière a été considérée le long d'un transect perpendiculaire au rivage et divisé en trois zones spatiales. Deux types de flux physiques interviennent donc : les flux verticaux de dépôt et remise en suspension, et les flux d'advection via la colonne d'eau. Des pistes d'amélioration et de nouvelles méthodes sont proposées. Un résultat sous forme statistique peut être obtenu en couplant l'utilisation de méthodes de Monte Carlo à l'analyse inverse pour la construction des réseaux trophiques. Les moyens d'étude des modèles ont été enrichis par la mise au point d'indices issus de la construction de chaînes de Markov et prenant en compte le caractère temporel des transferts de matière entre compartiments. Enfin, la transformation mathématique du modèle statique pour une étude dynamique de la stabilité de l'équilibre décrit est abordée. Plusieurs modèles ont été construits au cours de l'évolution des méthodes et de l'acquisition de connaissances sur le site. Des méthodes d'analyses existantes et d'autres mises au point dans le cadre de cet ouvrage ont été appliquées aux réseaux obtenus afin de faire émerger les propriétés du fonctionnement de la vasière et de souligner le rôle de certains compartiments. Des analyses de sensibilité permettent d'évaluer la robustesse des résultats et d'orienter les recherches futures en mettant en évidence les manques les plus cruciaux. Des données supplémentaires, notamment concernant les foraminifères benthiques, le zooplancton ou les mouvements verticaux du microphytobenthos permettront de fournir de meilleures contraintes et de valider (ou non) les résultats obtenus. Les principaux résultats montrent un système au fort caractère saisonnier dont les compartiments benthiques et pélagiques sont très liés. La production primaire benthique locale est un moteur important, mais qui ne suffirait pas à suppléer l'indispensable importation de matériel détritique. Le découpage de la vasière en trois zones fait apparaître les particularités de chacune. La zone centrale correspond à la description classique des « vasières intertidales européennes » : très productive, elle peut alimenter les autres régions. C'est une zone de production et d'exportation. La partie supérieure est moins productive et reçoit de la matière de la zone de milieu d'estran via la colonne d'eau. Sa production secondaire peut alors être exploitée par les limicoles, nombreux en hiver. C'est une zone de dégradation et d'exportation. Le bas d'estran dépend fortement des importations extérieures, « pompées » par les bivalves cultivés qui sont ainsi directement responsables d'une forte sédimentation sous les structures mytilicoles et ostréicoles. C'est une zone de transformation.

Droits : info:eu-repo/semantics/openAccess
http://archimer.ifremer.fr/doc/2005/these-2260.pdf
http://archimer.ifremer.fr/doc/00000/2260/

Résumé : Ifremer launched and coordinated the development of a strategy for the REBENT network (REseau BENThique) in 2000 to monitor the aftermath of the "Erika" oil spill in December 1999. Its aim is to provide consistent baseline knowledge about coastal benthic habitats and constitute a monitoring tool to detect changes at various scales over time and space. Sector-based seabed habitat mapping in shallow water (< 50 m deep), is currently being conducted throughout Brittany's coastal waters through a combination of geoacoustic marine systems and ground-truthing using biological grab sampling and seabed observations. Sedimentological and biological results on Glenan area emphasize a great diversity of subtidal habitats and marine species recognized. Sidescan imagery accentuates the complexity of the communities structure in a marine environment distinguished by strong and regulary roughness of the sea. Maerl biocenose is present at the nord-east of the archipelago. Progressively it gives way to mud sediment colonized by Amphiura filiformis and Haploops in the deeper channel. To the west and the south, substratum types are more coarse, occasionally mobiles, composed of essentially sand community with Nephtys and gravelly sand community with Branchiostoma lanceolatum.
Le Rebent (Réseau benthique), initié en 2000 à la suite de la catastrophe de l'Erika, a pour objectif de suivre les habitats benthiques côtiers et de détecter les changements à différentes échelles de temps et d'espace. L'approche sectorielle dans les petits fonds (< 50 m) des côtes bretonnes combine, des moyens de prospection acoustique, afin de délimiter les principaux types de substrats, avec des prélèvements et des observations biologiques pour caractériser les peuplements macrobenthiques. Les résultats des analyses sédimentologiques et faunistiques montrent autour de l'archipel des Glénan, une grande diversité d'habitats et d'espèces reconnues. L'imagerie acoustique fait ressortir la complexité de leur structuration dans un environnement marin soumis à de fortes et régulières périodes d'agitation. La biocénose de maërl occupe le nord-est de l'archipel. Elle laisse place progressivement aux sédiments envasés à Amphiura filiformis et aux vases à Haploops dans le fond du chenal. A l'ouest et au sud, les subtrats sont plus grossiers, essentiellement sableux à Nephtys et sablo-graveleux à Branchiostoma lanceolatum, épisodiquement mobiles.

Droits : info:eu-repo/semantics/openAccess
http://archimer.ifremer.fr/doc/2006/rapport-2301.pdf
http://archimer.ifremer.fr/doc/2006/sup-2301.pdf
http://archimer.ifremer.fr/doc/00000/2301/

Éditeur(s) : Adac-cryptogamie
Résumé : Very few attempts have been made in order to investigate the role of nutrients on cellular growth and toxin production in dinoflagellates associated with DSP (Diarrhetic Shellfish Poison). Some preliminary results are presented here, aiming at a better knowledge of inorganic nitrogen and organic phosphorus effects upon division rate and toxin content of Prorocentrum lima (PL2V spanish strain). Nitrogen have a positive effect on growth rate, up to a threshold value of 880muM.l-1. Above this threshold the rate decreases. There is no effect on toxin content since okadaic acid and DTX1 cell contents remain low (4.8 +/- 0.5 pg.cell.-1) and steady. Phosphorus effect upon division rate follows a non-linear relationship, whereas cellular toxic content is inversely proportional to growth rate.
Peu d'études ont été réalisées sur l'influence des nutriments sur la croissance et la toxicité de dinoflagellés producteurs de poisons diarrhéiques (Diarrhetic Shellfish Poison = DSP). Des résultats préliminaires sont présentés ici en ce qui concerne l'effef de concentrations croissantes d'azote inorganique et de phosphore organique sur le taux de division et la production toxinique de Prorocentrum lima (souche espagnole PL2V). L'azote a une influence positive sur la croissance de cette microalgue jusqu'à une valeur seuil de 880 μM.l#-1. Au-delà de ce seuil, le taux de division diminue. Par contre, l'effet sur la toxicité n'est pas significatif, les concentrations en acide okadaïque et DTXI restant relativement faibles (4.8 ± 0.5 pg.cell.· l ) et stables. Le phosphore agit intégralement sur le taux de division et il y a une relation inverse entre ce dernier et le contenu toxinique cellulaire.
Cryptogamie Algologie (0181-1568) (Adac-cryptogamie), 1992-08 , Vol. 13 , N. 3 , P. 187-195

Droits : info:eu-repo/semantics/openAccess
http://archimer.ifremer.fr/doc/00133/24469/22483.pdf
http://archimer.ifremer.fr/doc/00133/24469/

Résumé : This paper calls back the needs of cartography of the interface between lands and sea and assesses the characteristics of this interface in terms of knowledge as spatial and temporal constraints. After a brief typology of the different thematic cartographies of coasts and their applications we develop the contribution of the digital high resolution satellite image and we lean on an example (inventory of aquaculture sites in inter-tropical zone) which meets the three basic needs of localization, quantification and economic planning.
On rappelle les besoins de cartographie de l’interface entre terres et mers et on fait un bilan des caractéristiques de cette interface en termes de connaissances, de contraintes spatiales et temporelles. Après une typologie succincte de la cartographie des littoraux et de leurs applications on développe l‘apport de l’image numérique satellite de haute résolution et on s’appuie sur un exemple (celui de la présélection de sites aquacoles en zone intertropicale) qui répond aux trois besoins fondamentaux besoins de localisation, de quantification (inventaire) et de planification (prévision).

Droits : info:eu-repo/semantics/openAccess
http://archimer.ifremer.fr/doc/00189/29991/28439.pdf
http://archimer.ifremer.fr/doc/00189/29991/

Éditeur(s) : HAL CCSD
Résumé : The Green and Blue infrastructure (Trame verte et bleue ?TVB) is a new conservation policy tool based on the notions of ecological network and corridor. The TVB's implementation process establishes the connection of multi and nested decisional and action levels and needs permanent adjustment to change that is analyzed as adaptive governance mechanisms. The implementation of an adaptive governance is described as an mean to overpass those failures. The literature on adaptive governance gives learning process a central place as it permits to systematically improve policies and practices for an effective preservation of the environment. The aim of this article is to provide a critical perspective on learning processes in adaptive governance. We aim at reintroducing two blind spots. First, knowledge theory frequently forget to consider the strategic issue of knowledge. Second, knowledge theory implicitly recognizes that an actor acts but, it is often true that an actor can «be acted».
ESEE 2013 - Ecological Economics and Institutional Dynamics - 10th International Conference of the European Society for Ecological Economics
Lille, France

hal-01195358
https://hal.archives-ouvertes.fr/hal-01195358
PRODINRA : 226906

Éditeur(s) : HAL CCSD
Résumé : Given the technological development of embedded satellite sensors, the potential of available satellite images increases so that the question now arises of their most efficient exploitation possible. This is the purpose of the CARTAM-SAT project to fluidize the processing workflow from satellite images to users. The thesis is part of this framework.Processing operations relating to images have evolved over the years. Low-resolution images were processed by a so-called pixel approach while the high-resolution has allowed the development of a so-called object approach. The latter focuses on analysing not about the isolated pixels, but about groups of pixels representative of concrete objects on the ground. Thus, in principle, these are groups of pixels with a domain-specific remote sensing semantics.Along with satellite imagery, knowledge representation has evolved. The standards of representation have benefited from the expansion of the web to give rise to standards like OWL. This one is widely based on description logics that allow the use of automated reasoners able to infer implicit knowledge.This thesis is at the junction of these two sciences and provides an ontological approach for analysing satellite images. The aim is to formalize different types of knowledges and conceptualizations implicitly used by image processing programs and by remote sensing experts, and then reasoning automatically on an image description to obtain one semantic interpretation.This general principle may have numerous technical variations. The implementation consisted in a prototype combining a satellite image analysis library and an ontology-based reasoner. The implementation proposed in the thesis allows to explore four technical variations of the principle that lead to discussions on the complementarity of pixel and object analysis paradigms, the representation of some of the spatial relations and the role of knowledge in relation to processing.
Étant donnée l'évolution technologique des capteurs embarqués à bord des satellites, le potentiel d'images satellitaires accessible s'accroît de telle manière que se pose maintenant la question de son exploitation la plus efficace possible. C'est l'objectif du projet CARTAM-SAT que de fluidifier la chaîne de traitement depuis les satellites jusqu'aux utilisateurs des images. La thèse s'inscrit dans ce cadre. Les traitements relatifs aux images ont évolué au cours des années. Les images basse résolution étaient traitées par une approche dite pixel alors que la haute résolution a permis le développement d'une approche dite objet. Cette dernière s'attache à analyser non plus des pixels isolés, mais des groupes de pixels représentatifs d'objets concrets sur le terrain. Ainsi, en principe, ces groupes de pixels sont dotés d'une sémantique propre au domaine de la télédétection. La représentation des connaissances a évolué parallèlement aux images satellitaires. Les standards de représentation ont profité de l'expansion du web pour donner naissance à des standards comme OWL. Celui-ci repose en grande partie sur les logiques de description qui permettent l'utilisation de raisonneurs automatiques capables d'inférer une connaissance implicite.Cette thèse se place à la jonction de ces deux sciences et propose une approche ontologique d'analyse des images satellitaires. Il s'agit de formaliser différents types de connaissances et de conceptualisations implicitement utilisés par les logiciels de traitement d'image et par les experts en télédétection, puis de raisonner automatiquement sur la description d'une image pour en obtenir une interprétation sémantique.Ce principe général est susceptible de nombreuses déclinaisons techniques. La mise en œuvre a consisté en la réalisation d'un prototype alliant une bibliothèque d'analyse d'images satellitaires et un raisonneur basé sur les ontologies. L'implémentation proposée dans la thèse permet d'explorer quatre déclinaisons techniques du principe qui mènent à des discussions sur la complémentarité des paradigmes d'analyse pixel et objet, la représentation de certaines relations spatiales et la place de la connaissance par rapport aux traitements.
https://tel.archives-ouvertes.fr/tel-00998692

NNT : 2013MON20059
tel-00998692
https://tel.archives-ouvertes.fr/tel-00998692
https://tel.archives-ouvertes.fr/tel-00998692/document

Éditeur(s) : HAL CCSD Elsevier
Résumé : International audience
Predicting the impact of underground engineering on the environment requires the knowledge of natural media at different scales. In particular, understanding basic phenomena controlling the properties of rocks in the presence of complex fluids necessitates a detailed atomic description of the solid/fluid/solid contacts, the subject of Part I of the present study. First, building the solid interspace between two different crystals in a non-periodic situation is achieved using the ab initio and molecular mechanics code GenMol (TM). A description of the fluid confined within the interspace is then derived from the original genetic iterative multi-species (GIMS) algorithm implemented in the same code. This approach consists of equilibrating chemical potentials, cycle after cycle and species after species, between the confined fluid and the free natural fluid. An elementary iteration for a species k consists of different steps incrementing the number N-k of particles k, with other numbers N-k remaining constant. At each step, an optimum fluid composition is obtained by a genetic process distributing the fluid particles on a grid by stochastic shots, followed in fine by a refining process. The effectiveness of the GIMS approach is demonstrated in the case study of a fluid confined between two (0 0 1) kaolinite faces, with apertures h varying between 4 and 10 A. connected to a 9-species external solution [H2O, Cl-, Na+ CO2(aq), NaCl(aq), Ca2+, Mg2+, HCO3-, H3O+] where concentrations are ranging from 55 to 10(-4) mol/L. The results show a drastic variation in the solute/solvent and cations/ions ratios in the confined fluid when aperture h is lowered to less than 1 nm. These results obtained with a very rapid convergence of the iterative algorithm combined with a very competitive genetic optimizer are validated with high precision on a free solution. This description of contacts between crystals is original and unattainable by standard crystal interface approaches. It opens the way to understanding and/or predicting phenomena between crystals in a complex natural environment, such as adhesion or repulsion investigated in the Part II of this study.
ISSN: 0022-0248

hal-00544569
https://hal.archives-ouvertes.fr/hal-00544569
DOI : 10.1016/j.jcrysgro.2010.08.009

Éditeur(s) : Université de Bretagne Occidentale
Résumé : This activity report entitled (“Chemical contamination of the marine environment: from measurement to risk assessment”) summarizes the main stages my career at Ifremer from November 1975 to june 2013. The first chapter deals with the seawater chlorination and chlorinated waters released into the sea, the identification and the conditions of the formation of various by-product of these processes. The second chapter concerns PCBs, their nature, their chemical analysis in environmental matrices. PCBs are considered as the best examples of persistant and bioaccumulable compounds and therefore, in all this report they are flagship contaminants to which other groups of studied substances are compared. The third chapter refers to studies performed within marine pollution monitoring programme RNO (Réseau National d’Observation de la qualité de l’environnement marin - National observation network on the quality of the marine environnment) and well as other more limited studies like a first assessement on the presence of dioxins and dioxin-like PCBs in the French coastal marine environment and last, on the use of zebra mussel (Dresseinia polymorpha) as sentinelle species of the chemical contamination in the Seine estuary. The next two chapters are about bioaccumulation and about the distribution of organic contaminants (PCBs, dioxins, PAHs, PBDEs) in marine organisms and in marine foodwebs. These studies aim at a better knowledge of the presence and fate of these compounds in fish and marine organisms eitheir in an environmental perspective (chapter IV) or in order to contribute to the assessment of their health impact, or more precisely to estimate therelative part of fish and seafood to the human exposure to chemical residues (chapter V). To conclude, the chapter VI concerns the PCB and dioxin fingerprints in the various studied marine matrices ; analytical and environmental interpretations of the observed differences are suggested as well as possible applications.
Ce bilan d’activité intitulé « Contamination chimique du milieu marin : de la mesure à l’évaluation des risques » retrace les étapes essentielles de mon parcours à Ifremer entre novembre 1975 et juin 2013. Le premier chapitre traite de la chloration dans l’eau de mer et les rejets chlorés en mer, l’identification des sous-produits formés lors de ces traitements, les conditions de leur formation. Le second chapitre concerne la nature des PCB et leur analyse dans les matrices environnementales. Les PCB considérés comme les meilleurs exemples de composés persistants bioaccumulables constituent les « contaminants phares » de l’ensemble de ce travail et c’est par rapport aux PCB que sont comparés et évalués les autres groupes de contaminants étudiés. Le troisième chapitre se rapporte aux travaux réalisés dans le cadre de la surveillance RNO (Réseau National d’Observation de la qualité de l’environnement marin) ainsi que dans des études ponctuelles comme un premier inventaire sur les niveaux de présence des dioxines (PCDD et PCDF) dans l’environnement marin littoral ou sur l’utilisation de la moule zébrée (Dresseinia polymorpha) comme espèce indicatrice de la contamination de l’estuaire de la Seine. Les deux chapitres suivants sont consacrés aux travaux sur la bioaccumulation et aux contaminants organiques (PCB, dioxines, HAP, PBDE) dans les organismes et les réseaux trophiques marins soit dans une perspective environnementale sur le devenir des contaminants dans le vivant (chapitre IV) soit dans le cadre de l’évaluation des risques sanitaires ou, plus précisément, de l’estimation de la contribution de la consommation des produits de la mer à l’exposition de l’homme aux résidus chimiques (chapitre V). Pour terminer, le chapitre VI concerne les empreintes de PCB et de dioxines dans les différentes matrices étudiées ; une interprétation analytique et environnementale des différences observées est proposée ainsi que de possibles applications.

Droits : 2013 UBO
http://archimer.ifremer.fr/doc/00168/27946/26237.pdf
http://archimer.ifremer.fr/doc/00168/27946/

Éditeur(s) : HAL CCSD
Résumé : National audience
Endometriosis is a common gynecological estrogen-dependent disorder, affecting more than 10 % of women in reproductive age. This disease results in chronic pelvic pain and infertility and is characterized by the presence of functional endometrial tissue outside of uterine cavity. To date, the diagnosis of endometriosis takes many years because of the lack of non-invasive diagnostic tools. Interestingly, "Omics" technologies demonstrated their relevance for the search, identification and characterization of potential disease biomarkers with significant achievements in many areas in the field of human health. Use a panel of Omics approaches seems to be a good way to improve our knowledge about endometriosis. Despite several studies on the subject, the potential biomarkers obtained are still not used in the clinical practice, as it calls for large-scale validation. Combined approaches based on strong interdisciplinary collaborations should improve our knowledge of endometriosis, and allow the identification of specific predictive markers, thus leading to the development of therapeutic solutions for a non-invasive and early diagnosis of this debilitating disease. Copyright © 2017 John Libbey Eurotext.
Medecine Therapeutique Medecine de la Reproduction, Gynecologie et Endocrinologie

hal-01467551
https://hal-univ-rennes1.archives-ouvertes.fr/hal-01467551
DOI : 10.1684/mte.2016.0632

Éditeur(s) : Wiley / Blackwell
Résumé : P>New seismic reflection data from the Grand Banks of Newfoundland and the Newfoundland Basin add to the growing knowledge of the composition, structure and history of this non-volcanic margin. Geophysical imaging is now approaching the extent of that done previously on the conjugate margin along Iberia, providing a valuable database for the development of rifting models. Two parallel profiles over the shelf platform image deep crustal fabric representing Precambrian or possibly Appalachian deformation as well as Mesozoic extension. Progressively more intense extension of continental crust is imaged oceanwards without the highly reflective detachments frequently seen on profiles off Galicia. A landward-dipping event 'L' is imaged sporadically and appears to be analogous to a similar event on the Iberian IAM9 profile. The transition zone is probably exposed serpentinized mantle as interpreted off the Iberian margin although there appears to be a difference in the character of ridge development and reflectivity. The distinctive 'U' reflection identified previously at the base of the Newfoundland Basin deep water sedimentary section and recently identified as one or more thin basalt sills is imaged on newly presented profiles that connect previously published profiles SCR3 and SCR2 showing that 'U' is highly regular and continuous except where interrupted by basement highs. 'U' is also seen to have a major impact on the ability to image underlying basement. A full transect beginning over completely unextended continental crust through to oceanic crust has provided a data set from which estimates of extension and the pre-rifting location of the present continental edge can be made. Two estimates were obtained; 85 km based on faulting and 120 km based on crustal thickness.
Geophysical Journal International (0956-540X) (Wiley / Blackwell), 2009-08 , Vol. 178 , N. 2 , P. 1004-1020

Droits : 2009 Wiley / Blackwell
http://archimer.ifremer.fr/doc/2009/publication-6919.pdf
DOI:10.1111/j.1365-246X.2009.04162.x
http://archimer.ifremer.fr/doc/00000/6919/

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) : Pêche thonière et dispositifs de concentration de poissons, Caribbean-Martinique, 15-19 Oct 1999
Résumé : Since a few years, the catches of pelagic fish by artisanal fishermen of Reunion Island have strongly increased. Manpower and investments have been constant through the maintenance of about 30 fads all around the island. The traditional techniques of fishing pelagic fishes have been adapted in order to maintain a high level of catches and ensure the income of the fishermen. This report describes different techniques to capture pelagic fish on fads such as drift fishing, dragnet fishing and longline fishing. Knowledge, professional experience of fishermen are the main factors in setting fads and sustaining adaptability. The strong relation between the knowledge of the fishermen and the techniques is discussed. Then, the strategies of fishing, influenced by the environmental and seasonal conditions, and the species, are analysed.Original Abstract: L'activite de la petite peche a l'ile de La Reunion connait, depuis quelques annees, une periode d'expansion rapide de la production de poissons pelagiques. Ce developpement est d'autant plus remarquable qu'il s'effectue, en ce qui concerne la peche professionnelle artisanale, a effectif et investissement presque constants. Il est essentiellement du a la mise en place et a l'entretien d'un parc d'une trentaine de dispositifs de concentration de poissons (DCP), places tout autour de l'ile. Les techniques traditionnelles de peche de poissons pelagiques ont ete adaptees a ce nouveau concept, mais elles doivent continuellement evoluer et s'adapter aux modifications comportementales des poissons, afin de maintenir un niveau de capturabilite assurant les revenus des pecheurs. Cette etude s'attache a decrire les techniques de peche a la derive, a la traine et aux palangres, employees pour la capture de poissons pelagiques sur DCP. Bien que difficile a evaluer, l'experience du pecheur est un facteur determinant dans la mise en uvre de ces techniques et en permet l'amelioration constante. L'imbrication etroite entre le savoir-faire du pecheur et les techniques est egalement abordee et discutee. Enfin, les strategies de peche, fortement influencees par les conditions environnementales, les saisons et les especes rencontrees, y sont analysees.

Droits : info:eu-repo/semantics/openAccess
http://archimer.ifremer.fr/doc/00042/15294/12652.pdf
http://archimer.ifremer.fr/doc/00042/15294/

Éditeur(s) : Springer
Résumé : The distribution of summer phytoplankton across the Straits of Magellan (SOM) was studied with the aims of tracing differences among the distinct subregions of the area and contributing to the knowledge of its biodiversity. Samples collected at 25 stations were observed and counted in light microscopy. Selected samples were observed with transmission electron microscopy. The main unifying feature of the phytoplankton in the SOM was the high abundance and numerical dominance of small-sized (<10 μm) eukaryotic species, among which coccoid cells of <3 μm size were predominant (56.2 ± 30.6 of the total phytoplankton abundance). They mostly belonged to the prasinophyte Pycnococcus provasolii, which was abundant (0.8–6,834 cells × 103 ml−1) at all stations with the exception of those in proximity to the Atlantic entrances, where it was not recorded. Small-sized (<3 and 3–5 μm) diatoms (Minidiscus trioculatus, Lennoxia faveolata and other undetermined centric species) attained high densities (<3,757 cells 103 ml−1) especially at stations of the Patagonian sectors, whereas microplanktonic diatoms were only found at the two entrances of the Straits. Dinoflagellates were constituted mainly by >10 μm forms in the Andean subregion and <10 μm naked species in the Patagonian subregion, contributing up to 75.9 and 41.8% of the total carbon in these two areas, respectively. In the Patagonian subregion, flagellates mainly constituted by <5 μm forms and by cryptomonads <10 μm comprised up to 53.9% of the total biomass. Several species identified in this study have never been reported in other investigations in the SOM, while others, including Pycnococcus provasolii and Lennoxia faveolata, have rarely been recorded elsewhere. Overall, the summer phytoplankton of the Straits does not resemble that of any other region of the world’s seas. Although some of the predominant species might have been overlooked elsewhere, their abundance and relative importance apparently constitute a distinctive feature of the SOM.
Polar Biology (0722-4060) (Springer), 2011 , Vol. 34 , N. 9 , P. 1269-1284

Droits : The Author(s) 2010. This article is published with open access at Springerlink.com
http://archimer.ifremer.fr/doc/00026/13722/10828.pdf
DOI:10.1007/s00300-010-0937-2
http://archimer.ifremer.fr/doc/00026/13722/

Éditeur(s) : Université des Antilles Études caribéennes
Résumé : Sur fond de crise du tourisme au Nord, de la globalisation de l’économie et de l’accélération des mobilités, une évolution des formes de développement touristiques semble à l’œuvre dans les confins géographiques. Dans certains territoires touristiques du fait de conflits dans l’usage des ressources naturelles, des pratiques récréatives alternatives émergent qui combinent une logique économique avec des préoccupations socio-environnementales.Notre article analyse l’apparition du tourisme scientifique dans la région « non-touristique » de Aysén, en Patagonie chilienne. Des acteurs d’un territoire se mobilisent selon des pôles culturels et des axes thématiques autour de projets pilotes, de recherche expérientielle et de médiations scientifiques innovantes. Sur ce front pionnier, un réseau informel d’acteurs coordonne ses actions pour aborder les problématiques sociales et environnementales de leur territoire. Opérateurs et prestataires pour le tourisme scientifique créent de manière participative une offre originale. Un système touristique alternatif, axé sur la protection de l’environnement, de la culture et des dynamiques sociales de la communauté d’accueil, favorise l’acquisition et le partage de savoirs entre scientifiques, acteurs locaux et visiteurs.Le tourisme scientifique s’inscrit-il dans une évolution globale des pratiques touristiques ? En proposant de dépasser les frontières, entre activités récréatives et le travail, de lieux de vie et de loisir, il apparaît comme l’expression d’un « après-tourisme ». L’hybridation des pratiques, une approche scientifique associée à l’esprit de la découverte inhérent au voyage, semble pouvoir relever des défis sociétaux liés à l’essor d’un tourisme globalisé. Alors que le tourisme est pensé depuis longtemps en termes de transfert de compétences, de modèles et d’ingénierie du Nord vers le Sud, une périphérie propose de nouveaux cadres de pensée, d’action et de participation qui renouvellent le sens du voyage.
In the context of a tourism crisis in the north, a globalized economy and an increase of mobility, a change in the forms of tourism development seems to occur in peripheral areas. In some tourism areas and due to conflicts over the use of natural resources, alternative recreational practices arise that combine economic needs and socio-environmental concerns.Our article analyzes the appearance of scientific tourism in the "non-tourist" region of Aysén, in Chilean Patagonia. Actors of a territory unite according to specific cultural poles and thematic axes through experiential research and innovative scientific mediation pilot projects. On this pioneer front, an informal network of stakeholders coordinates its actions to address the social and environmental issues of their territory. Operators and service providers for scientific tourism create an innovative offer in a participatory process. An alternative tourism system, focused on protecting the environment, the culture and social dynamics of the host community, promotes the acquisition and sharing of knowledge between scientists, local actors and visitors.Is scientific tourism part of a global evolution of tourism practices? By proposing to go beyond established boundaries, of recreational activities and work, everyday places and leisure areas, it appears as the expression of an “After-Tourism”. The hybridization of practices, a scientific approach associated with the spirit of the discovery inherent of the travel experience, seems to respond to the challenges of the community confronted to the rise of a globalized tourism. While tourism has always been thought of in terms of transfer of skills, models and engineering from the North to the South, a periphery offers new frameworks of thought, action and participation that renew the meaning of travel.
En un escenario de crisis del turismo en los países desarrollados, de la globalización de la economía y del incremento de las movilidades, una evolución de las formas de desarrollo del turismo parece estar en marcha en los confines geográficos. En ciertos territorios turísticos, debido a los conflictos de uso de los recursos naturales, prácticas recreativas alternativas surgen que combinan una lógica económica con preocupaciones socio-ambientales.El presente artículo analiza el surgimiento del turismo científico en la región “no-turística” de Aysén en la Patagonia chilena. Actores del territorio se unen según polos y temáticas científicas, a través de proyectos pilotos, de investigación experiencial y mediaciones científicas innovadoras. En este frente pionero, una red informal se organiza para abordar las problemáticas sociales y ambientales de su territorio. Operadores y proveedores de servicios para el turismo científico crean de manera participativa una oferta novedosa. Un sistema turístico alternativo, basado en el cuidado del medio ambiente, de la cultura y de las dinámicas sociales del comunidad de acogida, favorece la adquisición y el intercambio de conocimientos entre científicos, actores locales y visitantes. ¿Será la aparición del turismo científico la expresión de una evolución global de las practicas turísticas? Al invitar a que sean sobrepasadas las fronteras, entre actividades recreativas y el trabajo, lugares de vida y sitios de esparcimiento, este se presenta como un “Pos-Turismo”. La hibridación de las prácticas, una aproximación científica asociada al espíritu de descubrimiento inherente del viaje, parece poder resolver los desafíos de nuestras sociedades vinculados al auge de un turismo globalizado. Cuando el turismo suele ser pensado desde hace mucho, como un proceso de transferencia de capacidades, de modelos y de ingenierías, del Norte hacia el Sur, una periferia propone nuevos marcos conceptuales, de acción y de participación, que renuevan el sentido del viaje.
Patagonie

Droits : info:eu-repo/semantics/openAccess
urn:doi:10.4000/etudescaribeennes.11169
http://journals.openedition.org/etudescaribeennes/11169

Éditeur(s) : HAL CCSD
Résumé : International audience
The French ministry of education introduced in 2005 the « organized returning of knowledge » (ROC) in the French baccalauréat as a tool to render more efficient the mathematical education at the end of secondary school. This article is based on an analysis of the ROC of the 2006 Antilles-Guyane baccalauréat, by the anthropological approach to didactics, which leads to the construction of its mathematical site. Through this analysis, some features of the ROC are discussed, such as its consistency (including from the view point of the institution) and the transparency of this evaluation.
L’introduction des restitutions organisées de connaissances (ROC) dans les épreuves du baccalauréat, à partir de 2005, est une réponse de l’institution à la volonté de rendre plus efficace l’enseignement en cycle terminal. Cet article s’appuie sur l’analyse de la ROC du sujet Antilles Guyane session 2006 par une approche anthropologique en proposant la construction de son site mathématique. Au travers de cet exemple sont interrogées certaines caractéristiques du concept ROC comme sa cohérence (notamment institutionnelle) et la transparence de cette évaluation.
Annales de didactique et de sciences cognitives

hal-01530860
https://hal.univ-antilles.fr/hal-01530860

Éditeur(s) : HAL CCSD
Résumé : The trophic endosymbiosis interaction between a cnidarian host and its photosynthetic dinoflagellatessymbionts form the basis of coral reef ecosystems. Cnidarians host their symbionts in gastrodermis cells, in a phagocytosis-derived vacuole. Establishment and maintenance of the symbiotic interaction depend on an intimate molecular communication between the two partners. However, environmental and/or anthropogenic disturbances can lead to the breakdown of the symbiotic association, which is responsible for the worldwide decline of coral reefs. The main objectives of my research project are to improve the knowledge regarding symbiosis maintenance and disruption mechanisms, but also to define the molecular key players involved at the symbiotic interface in the sea anemone, Anemonia viridis. First, we have described the cellular mechanisms involved in the different types of symbiosis breackdown. Meanwhile, the characterization of npc1 and npc2 genes (involved in endosomal sterol transport), showed a duplication and a sub-functionalization of the npc2d gene. Both NPC1 and NPC2 proteins are expressed around symbionts. We therefore suggest that the duplicated protein NPC2-d is a biomarker of symbiosis health and that NPC1 protein is a marker of the perisymbiotic membrane. We then developed a protocol to characterize the proteome of the symbiotic interface between the two symbiotic partners. The newly-identified symbiotic key players will increase the general knowledge on the symbiotic interaction and its regulation during both stable and bleaching conditions.
L’endosymbiose trophique établie entre un hôte Cnidaire et ses symbiotes Dinoflagellés photosynthétiques est à l’origine du succès évolutif des écosystèmes coralliens. Les symbiotes sont internalisés par un mécanisme de phagocytose et maintenus dans les cellules du gastroderme de l'hôte. La symbiose est régie par un dialogue moléculaire intime entre les deux partenaires, interrompu lors de perturbations environnementales ou anthropiques, responsables du déclin mondial des récifs coralliens. Les objectifs de mon projet de recherche sont de définir les acteurs moléculaires localisés à l’interface symbiotique chez l’anémone de mer, Anemonia viridis. Premièrement, nous avons étudié les mécanismes cellulaires impliqués dans différents types de rupture de la symbiose et mis en évidence des phénomènes d’apoptose, nécrose et symbiophagie. Parallèlement, nous avons caractérisé chez l’anémone les gènes npc1 et npc2, impliqués chez les vertébrés dans le transport endosomal de stérols, et dont l’expression est modulée par l’état symbiotique. Nous avons pu montrer que le gène npc2d est issus d’une duplication et vraisemblablement d’une sub-fonctionnalisation et que les protéines NPC1 et NPC2 sont exprimées au voisinage des symbiotes. Nous proposons donc que la protéine NPC2-d soit utilisée comme marqueur de l’état de santé des Anthozoaires symbiotiques et que la protéine NPC1 soit un marqueur de la membrane périsymbiotique. Nous avons également développé un protocole afin d’identifier les protéines associées à l’interface symbiotique entre les deux partenaires. A terme, les cibles identifiées permettront une meilleure compréhension des mécanismes qui régulent la relation symbiotique.
https://tel.archives-ouvertes.fr/tel-01673491

NNT : 2015NICE4105
tel-01673491
https://tel.archives-ouvertes.fr/tel-01673491
https://tel.archives-ouvertes.fr/tel-01673491/document
https://tel.archives-ouvertes.fr/tel-01673491/file/2015NICE4105.pdf

Éditeur(s) : HAL CCSD Elsevier
Résumé : International audience
ETHNOPHARMACOLOGICAL RELEVANCE: Cutaneous leishmaniasis is a neglected disease with a high incidence in French Guiana, mainly in the middle and upper Oyapock basin, where Amerindian and some Brazilian people live. The main goals of this work were (i) to assess the knowledge about leishmaniasis in the different populations of the middle and upper Oyapock basin, (ii) to study the therapeutic strategies adopted by people affected by leishmaniasis and (iii) to document the use of phytotherapeutic remedies for leishmaniasis. Knowledge, attitudes and practices (K.A.P.) related to this disease and its treatments have been studied according to cultural group and geographical settlement. Within the Wayãpi group, the evolution of the knowledge of phytoremedies over the last 20 years has been characterised by literature-based comparisons. MATERIALS AND METHODS: A total of 144 questionnaires were administered in all the villages of the upper Oyapock and Camopi basins. Correspondence analyses were used for multivariate analysis. Plant species were identified at the Cayenne Herbarium (CAY). RESULTS: The biomedical concept of leishmaniasis correlates well with the Teko and Wayãpi concepts of kalasapa and kalasapau. Although the vector of this disease was not correctly identified, the most commonly cited aetiology (74.5%) was vector-borne, and related epidemiological schemes correlate well with the one encountered in French Guiana. Theoretically and practically, health centres were the most commonly used resource for diagnostic in instances of leishmaniasis infection (65.9%), independently of the patient's cultural group, along with the use of pharmaceutical drugs (85.3%). Pharmaceuticals were commonly utilised despite the frequent (51.5%) use of phytotherapeutic remedies, alone or in combination with drugs. The most cited medicinal plant species for the treatment of leishmaniasis included Eleutherine bulbosa (Mill.) Urb. (Iridaceae, cited 14 times), Euterpe oleracea Mart. (Arecaceae, 9), Cecropia obtusa Trecul (Cecropiaceae, 8), Jatropha curcas L. (Euphorbiaceae, 7), Ceiba pentandra (L.) Gaertn. (Bombacaceae, 6) and Carica papaya L. (Caricaceae, 6). Multiple correspondence analyses demonstrated that the species used in leishmaniasis remedies are more prone to vary by the user's place of residence than by their cultural origin, which indicates that exchange of knowledge about leishmaniasis remedies has occurred across different cultural groups. Literature-based comparisons between the remedies for leishmaniasis used by the Wayãpi during the 1980s showed a striking evolution, both in terms of diversity of species and number of plants used. The large number of species shared with other Guianese groups argues for intercultural exchange and may explain the majority (57.1%) of the newly used species highlighted in our study. CONCLUSIONS: Leishmaniasis is a well-known disease in the studied area. Phytotherapeutic treatments are still in use, although they are not the main source of remedies, and should undergo pharmacological studies to evaluate their potential therapeutic value.
ISSN: 0378-8741

pasteur-00634597
https://hal-riip.archives-ouvertes.fr/pasteur-00634597
DOI : 10.1016/j.jep.2011.07.044
PUBMED : 21816216