106 research outputs found

    Changes in protein expression in mussels Mytilus galloprovincialis dietarily exposed to PVP/PEI coated silver nanoparticles at different seasons

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    Potential toxic effects of Ag NPs ingested through the food web and depending on the season have not been addressed in marine bivalves. This work aimed to assess differences in protein expression in the digestive gland of female mussels after dietary exposure to Ag NPs in autumn and spring. Mussels were fed daily with microalgae previously exposed for 24 hours to 10 ”g/L of PVP/PEI coated 5 nm Ag NPs. After 21 days, mussels significantly accumulated Ag in both seasons and Ag NPs were found within digestive gland cells and gills. Two-dimensional electrophoresis distinguished 104 differentially expressed protein spots in autumn and 142 in spring. Among them, chitinase like protein-3, partial and glyceraldehyde-3-phosphate dehydrogenase, that are involved in amino sugar and nucleotide sugar metabolism, carbon metabolism, glycolysis/gluconeogenesis and the biosynthesis of amino acids KEGG pathways, were overexpressed in autumn but underexpressed in spring. In autumn, pyruvate metabolism, citrate cycle, cysteine and methionine metabolism and glyoxylate and dicarboxylate metabolism were altered, while in spring, proteins related to the formation of phagosomes and hydrogen peroxide metabolism were differentially expressed. Overall, protein expression signatures depended on season and Ag NPs exposure, suggesting that season significantly influences responses of mussels to NP exposure.This work has been funded by the Spanish Ministry of Economy and Competitiveness (NanoSilverOmics project MAT2012-39372), Basque Government (SAIOTEK project S-PE13UN142 and Consolidated Research Group GIC IT810-13) and the University of the Basque Country UPV/EHU (UFI 11/37 and PhD fellowship to N.D.). This study had also the support of Fundação para a CiĂȘncia e Tecnologia (FCT) from Portugal through the Strategic Project UID/MAH00350/2013 granted to CIMA. The contribution of K. Mehennaoui was possible within the project NanoGAM (AFR-PhD-9229040) and M. Mikolaczyk was supported by a PhD fellowship from the French Ministry of Higher Education and Research.info:eu-repo/semantics/acceptedVersio

    The KerBabel experience : an adventure in the 'new' knowledge economy

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    Cette thĂšse retrace les presque vingt annĂ©es de l’expĂ©rience KerBabel menĂ©e au sein du C3ED puis de REEDS, Ă  l’universitĂ© de Versailles-Saint-Quentin-en-Yvelines, de 2000 Ă  nos jours. Nous y abordons le thĂšme de l’économie de la connaissance, Ă  travers le prisme de plusieurs Ă©tudes de cas. Nous questionnons la valeur d’une co-construction dans une approche transdisciplinaire, entre les problĂ©matiques du dĂ©veloppement durable et l’apport du numĂ©rique. Nous exposons notamment comment un processus de recherche-action a pu engendrer de nombreuses rĂ©alisations, produire les livrables requis par de multiples projets internationaux, et d’en capitaliser les rĂ©sultats afin d’atteindre une architecture technique et numĂ©rique globale in fine.Nous exposons une sĂ©lection des diffĂ©rentes expĂ©riences oĂč les processus de production, de transfert et d’usage des savoirs ont eu lieu. Le champ opĂ©ratoire concerne la Recherche et l’Education, et plus particuliĂšrement la mĂ©diation de connaissances dans le domaine de l’économie Ă©cologique. L’objectif est de faire l’état des lieux des Ă©tudes et projets oĂč le numĂ©rique a jouĂ© un rĂŽle. En quoi l’alliage connaissance-digital rĂ©pond aux enjeux de la recherche et de l’éducation, c’est-Ă -dire comme moyen de la recherche et objet de la recherche, ou comme moyen pour l’éducation et objet pour l’éducation.Nous montrons de quelle façon la mĂ©diation des connaissances et les partenariats ont pu ĂȘtre mobilisĂ©s sur des Ă©tudes de cas Ă  des Ă©chelles variables.Nous dĂ©crivons les systĂšmes multimĂ©dias d’aide Ă  l’apprentissage et Ă  la dĂ©libĂ©ration (SMMAAD) ainsi que les autres crĂ©ations des Ă©quipes KerBabel. Nous dĂ©crivons et. interrogeons particuliĂšrement l’aboutissement de l’intĂ©gration des diffĂ©rentes expĂ©riences Ă  travers la plateforme online ePLANETe. Un des intĂ©rĂȘts de ce travail est de tĂ©moigner d’un exercice sur le temps long (Ă  l’échelle du numĂ©rique). Ce recul permet de questionner l’apport des innovations du secteur des technologies de l’information et des communicationsPeuvent-elles jouer un rĂŽle majeur dans la situation de crise environnementale dans laquelle nous sommes ? Nous questionnons Ă©galement en quoi la structure de la plateforme ePLANETe globalise les questions environnement, Ă©conomie, Ă©ducation et sociĂ©tĂ©, comme une rĂ©ponse aux problĂ©matiques de choix social. Dans un contexte d’urgence climatique, la question de l’importance des partenariats prend un relief nouveau. Il nous semble que l’expĂ©rience KerBabel apporte un dĂ©but de rĂ©ponse originale qui mĂ©riterait d’ĂȘtre adaptĂ©e Ă  un moment oĂč les intelligences artificielles provoquent un nouveau stress, pour certains, ou une nouvelle opportunitĂ© pour le dĂ©veloppement des connaissances et des partenariats, pour d’autres.La prise en compte de ces variĂ©tĂ©s d’opinions est au centre des approches multi-acteurs et multi-critĂšres de l’outillage de l’expĂ©rience KerBabel. Cette thĂšse propose une immersion dans cette aventure collĂ©giale. AprĂšs avoir dĂ©fini le cadre de l’expĂ©rience, nous proposons un « transfert de connaissance » en utilisant la structure mĂȘme de la plateforme ePLANETe. Nous passerons donc par les 6 portes (ou Doorways) thĂ©matiques qui abordent notamment chacune des quatre sphĂšres de la soutenabilitĂ©. Nous finirons enfin par l’esquisse d’une auto-Ă©valuation de la qualitĂ© de la plateforme par
elle-mĂȘme. Cette approche nous permet de dĂ©montrer les principes de gĂ©nĂ©ricitĂ© qui lui sont propre et d’apporter une rĂ©ponse par l’expĂ©rience rĂ©flexive.This thesis retraces the almost twenty years of the KerBabel experiment conducted within the C3ED and then REEDS, at the University of Versailles-Saint-Quentin-en-Yvelines, from 2000 to the present day. We discuss the theme of the knowledge economy, through the prism of several case studies. We question the value of co-construction in a transdisciplinary approach, between the issues of sustainable development and the contribution of digital technology. In particular, we describe how an action-research process has generated many achievements, produced the deliverables required by multiple international projects, and capitalized on the results in order to achieve a global technical and digital architecture in fine.We present a selection of the different experiences where the processes of production, transfer and use of knowledge have taken place. The field of operation concerns Research and Education, and more particularly the mediation of knowledge in the field of ecological economics. The objective is to take stock of studies and projects in which digital technology has played a role. How the knowledge-digital alloy responds to the challenges of research and education, i.e. as a means of research and object of research, or as a means for education and object of education.We show how knowledge mediation and partnerships have been mobilized on case studies at various scales. We describe the multimedia learning and deliberation support systems (SMMAAD) and other creations of KerBabel teams. We describe and question in particular the successful integration of the different experiences through the online platform ePLANETe. One of the interests of this work is to testify to an exercise on long time (on a digital scale). This decline allows us to question the contribution of innovations in the information and communication technologies sectorCan they play a major role in the environmental crisis situation in which we find ourselves? We also question how the structure of the ePLANETe platform globalizes environmental, economic, educational and social issues as a response to social choice issues. In a context of climate emergency, the question of the importance of partnerships takes on a new dimension. It seems to us that the KerBabel experience provides the beginning of an original response that deserves to be adapted at a time when artificial intelligence is causing new stress, for some, or a new opportunity for the development of knowledge and partnerships, for others.Taking these varieties of opinion into account is at the heart of the multi-stakeholder and multi-criteria approaches of the KerBabel experience toolkit. This thesis proposes an immersion in this collegial adventure. After having defined the framework of the experiment, we propose a "knowledge transfer" using the very structure of the ePLANETe platform. We will therefore pass through the 6 thematic doors (or Doorways) that address each of the four spheres of sustainability. Finally, we will end with the outline of a self-assessment of the quality of the platform by...itself. This approach allows us to demonstrate the principles of genericity that are specific to it and to provide an answer through reflective experience

    Proprietes dynamiques des solutions aqueuses de tertio-butanol : comparaison avec d'autres melanges eau-alcool

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    SIGLET 55182 / INIST-CNRS - Institut de l'Information Scientifique et TechniqueFRFranc

    L'expérience KerBabel : une aventure dans la "nouvelle" économie de la connaissance

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    This thesis retraces the almost twenty years of the KerBabel experiment conducted within the C3ED and then REEDS, at the University of Versailles-Saint-Quentin-en-Yvelines, from 2000 to the present day. We discuss the theme of the knowledge economy, through the prism of several case studies. We question the value of co-construction in a transdisciplinary approach, between the issues of sustainable development and the contribution of digital technology. In particular, we describe how an action-research process has generated many achievements, produced the deliverables required by multiple international projects, and capitalized on the results in order to achieve a global technical and digital architecture in fine.We present a selection of the different experiences where the processes of production, transfer and use of knowledge have taken place. The field of operation concerns Research and Education, and more particularly the mediation of knowledge in the field of ecological economics. The objective is to take stock of studies and projects in which digital technology has played a role. How the knowledge-digital alloy responds to the challenges of research and education, i.e. as a means of research and object of research, or as a means for education and object of education.We show how knowledge mediation and partnerships have been mobilized on case studies at various scales. We describe the multimedia learning and deliberation support systems (SMMAAD) and other creations of KerBabel teams. We describe and question in particular the successful integration of the different experiences through the online platform ePLANETe. One of the interests of this work is to testify to an exercise on long time (on a digital scale). This decline allows us to question the contribution of innovations in the information and communication technologies sectorCan they play a major role in the environmental crisis situation in which we find ourselves? We also question how the structure of the ePLANETe platform globalizes environmental, economic, educational and social issues as a response to social choice issues. In a context of climate emergency, the question of the importance of partnerships takes on a new dimension. It seems to us that the KerBabel experience provides the beginning of an original response that deserves to be adapted at a time when artificial intelligence is causing new stress, for some, or a new opportunity for the development of knowledge and partnerships, for others.Taking these varieties of opinion into account is at the heart of the multi-stakeholder and multi-criteria approaches of the KerBabel experience toolkit. This thesis proposes an immersion in this collegial adventure. After having defined the framework of the experiment, we propose a "knowledge transfer" using the very structure of the ePLANETe platform. We will therefore pass through the 6 thematic doors (or Doorways) that address each of the four spheres of sustainability. Finally, we will end with the outline of a self-assessment of the quality of the platform by...itself. This approach allows us to demonstrate the principles of genericity that are specific to it and to provide an answer through reflective experience.Cette thĂšse retrace les presque vingt annĂ©es de l’expĂ©rience KerBabel menĂ©e au sein du C3ED puis de REEDS, Ă  l’universitĂ© de Versailles-Saint-Quentin-en-Yvelines, de 2000 Ă  nos jours. Nous y abordons le thĂšme de l’économie de la connaissance, Ă  travers le prisme de plusieurs Ă©tudes de cas. Nous questionnons la valeur d’une co-construction dans une approche transdisciplinaire, entre les problĂ©matiques du dĂ©veloppement durable et l’apport du numĂ©rique. Nous exposons notamment comment un processus de recherche-action a pu engendrer de nombreuses rĂ©alisations, produire les livrables requis par de multiples projets internationaux, et d’en capitaliser les rĂ©sultats afin d’atteindre une architecture technique et numĂ©rique globale in fine.Nous exposons une sĂ©lection des diffĂ©rentes expĂ©riences oĂč les processus de production, de transfert et d’usage des savoirs ont eu lieu. Le champ opĂ©ratoire concerne la Recherche et l’Education, et plus particuliĂšrement la mĂ©diation de connaissances dans le domaine de l’économie Ă©cologique. L’objectif est de faire l’état des lieux des Ă©tudes et projets oĂč le numĂ©rique a jouĂ© un rĂŽle. En quoi l’alliage connaissance-digital rĂ©pond aux enjeux de la recherche et de l’éducation, c’est-Ă -dire comme moyen de la recherche et objet de la recherche, ou comme moyen pour l’éducation et objet pour l’éducation.Nous montrons de quelle façon la mĂ©diation des connaissances et les partenariats ont pu ĂȘtre mobilisĂ©s sur des Ă©tudes de cas Ă  des Ă©chelles variables.Nous dĂ©crivons les systĂšmes multimĂ©dias d’aide Ă  l’apprentissage et Ă  la dĂ©libĂ©ration (SMMAAD) ainsi que les autres crĂ©ations des Ă©quipes KerBabel. Nous dĂ©crivons et. interrogeons particuliĂšrement l’aboutissement de l’intĂ©gration des diffĂ©rentes expĂ©riences Ă  travers la plateforme online ePLANETe. Un des intĂ©rĂȘts de ce travail est de tĂ©moigner d’un exercice sur le temps long (Ă  l’échelle du numĂ©rique). Ce recul permet de questionner l’apport des innovations du secteur des technologies de l’information et des communicationsPeuvent-elles jouer un rĂŽle majeur dans la situation de crise environnementale dans laquelle nous sommes ? Nous questionnons Ă©galement en quoi la structure de la plateforme ePLANETe globalise les questions environnement, Ă©conomie, Ă©ducation et sociĂ©tĂ©, comme une rĂ©ponse aux problĂ©matiques de choix social. Dans un contexte d’urgence climatique, la question de l’importance des partenariats prend un relief nouveau. Il nous semble que l’expĂ©rience KerBabel apporte un dĂ©but de rĂ©ponse originale qui mĂ©riterait d’ĂȘtre adaptĂ©e Ă  un moment oĂč les intelligences artificielles provoquent un nouveau stress, pour certains, ou une nouvelle opportunitĂ© pour le dĂ©veloppement des connaissances et des partenariats, pour d’autres.La prise en compte de ces variĂ©tĂ©s d’opinions est au centre des approches multi-acteurs et multi-critĂšres de l’outillage de l’expĂ©rience KerBabel. Cette thĂšse propose une immersion dans cette aventure collĂ©giale. AprĂšs avoir dĂ©fini le cadre de l’expĂ©rience, nous proposons un « transfert de connaissance » en utilisant la structure mĂȘme de la plateforme ePLANETe. Nous passerons donc par les 6 portes (ou Doorways) thĂ©matiques qui abordent notamment chacune des quatre sphĂšres de la soutenabilitĂ©. Nous finirons enfin par l’esquisse d’une auto-Ă©valuation de la qualitĂ© de la plateforme par
elle-mĂȘme. Cette approche nous permet de dĂ©montrer les principes de gĂ©nĂ©ricitĂ© qui lui sont propre et d’apporter une rĂ©ponse par l’expĂ©rience rĂ©flexive

    Silver : sources, transfer and bioaccumulation : case of the Gironde fluvio-estuarine system

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    Les rejets d’argent (Ag) dans l’environnement liĂ©s Ă  l’exploitation miniĂšre aux diverses applications industrielles (e.g. bijouterie, mĂ©decine, photographie, Ă©lectronique et plus rĂ©cemment les nanotechnologies) font de Ag un polluant historique et Ă©mergent, dont les transferts et les effets dans les milieux aquatiques sont largement sous-documentĂ©s. Ce travail prĂ©sente un premier bilan des sources, du transfert et de la bioaccumulation de Ag dans le systĂšme fluvio-estuarien de la Gironde. Le continuum Lot-Garonne-Gironde, connu pour une pollution polymĂ©tallique (e.g. Cd, Zn) provenant du bassin de Decazeville, est un systĂšme modĂšle pour l’étude des transferts mĂ©talliques du continent Ă  l’ocĂ©an. Les enregistrements des signaux historiques (~50 ans) de Ag dans les sĂ©diments du Lot en amont (Ag : 0,3 mg/kg) et en aval (Ag : jusqu’à 7 mg/kg) du bassin de Decazeville sont similaires Ă  ceux de Cd, indiquant des sources et des processus de transport/dĂ©pĂŽt communs liĂ©s Ă  l’histoire miniĂšre et industrielle jusqu’en 1986. Le lessivage et l’érosion actuels des terrils provoquent localement des concentrations en Ag particulaire (AgP : 260 mg/kg) et dissous (AgD : 1260 ng/l) dans la riviĂšre Riou-Mort qui sont 2 Ă  3 ordres de grandeur supĂ©rieures aux valeurs typiques. MalgrĂ© ces fortes concentrations, la contribution du Riou-Mort aux flux de Ag de la Garonne (AgD : 0,008 Ă  0,041 t/an ; AgP : 0,306 Ă  2,44 t/an ; 1999-2009) reste faible (AgP : <11% ; AgD : <6%). La Garonne transporte l’essentiel (63-83%) des apports en Ag Ă  l’estuaire principalement sous forme particulaire (96±2%). La dĂ©termination du bruit de fond gĂ©ochimique rĂ©gional (AgP/ThP=0,026) a permis d’évaluer (i) la contribution naturelle (20% Ă  65%) aux flux totaux en AgP et (ii) les flux anthropiques spĂ©cifiques de AgP (15±10 g/kmÂČ/an et 0,24±0,16 g/hab/an) Ă  l’échelle du bassin versant de la Garonne (La RĂ©ole). Dans l’estuaire salin, la dĂ©sorption par les ions chlorures libĂšre ~60% de AgP vers la colonne d’eau (addition), provoquant des concentrations maximales en AgD (6-8 ng/l) Ă  salinitĂ© 15-25. La fraction en Ag dĂ©sorbĂ© correspond Ă  la fraction potentiellement biodisponible ou rĂ©active (i.e. extractible par HCl 1 M). Ainsi, les premiĂšres estimations des flux nets indiquent que l’export annuel de Ag vers le domaine cĂŽtier est Ă  50-80% liĂ© Ă  la phase dissoute (0,64 Ă  0,89 t/an en 2008 et 0,56 Ă  0,77 t/an en 2009). Bien que plus biodisponible sous forme ionique Ag+ (dominante en eau douce), l’accumulation de Ag dans les organismes estuariens (huĂźtres, crevettes et anguilles) reflĂšte la pression d’exposition supĂ©rieure en eau saumĂątre. L’exposition in situ d’anguilles europĂ©ennes, espĂšce recommandĂ©e pour la biosurveillance du milieu dans le cadre de la Directive Cadre sur l’Eau, dans des cages Ă  diffĂ©rents sites clĂ© de l’estuaire pendant 3 mois, a mis en Ă©vidence les voies directes et trophiques de la contamination en Ag Ă  des niveaux de contamination environnementaux. L’enregistrement historique de la contamination en Ag des huĂźtres de la Gironde (1979-2007, RNO, Ifremer) indique que le bassin de Decazeville a Ă©tĂ© la source majoritaire en Ag jusqu’en ~1988. Cependant, l’accumulation maximale de Ag dans ces bivalves aprĂšs 1993 (de ~40 Ă  plus de 100 mg/kg, poids sec) rĂ©vĂšle une contribution croissante de sources additionnelles et contemporaines en Ag comme la photographie, l’ensemencement des nuages (30 Ă  63 kg/an) ou encore les rejets des eaux usĂ©es urbaines de Toulouse et de Bordeaux (42 et 57 kg/an). Ce travail constitue une base nĂ©cessaire Ă  l’étude des rejets du cycle de Ag (y compris les nanoparticules) dans le milieu aquatique (quantification, transfert et toxicitĂ©) et des risques associĂ©s.Silver (Ag) emissions into the environment from former mining activities and various industrial applications (e.g. jewellery, medicine, photography, electronic products and more recently nanotechnology) make Ag both a historic and an emergent pollutant for which information on its transfer and toxicity in aquatic system are scarce. This work provides a first assessment of Ag sources, transfer and bioaccumulation in the Gironde fluvial-estuarine system. The Lot-Garonne-Gironde River continuum, known for its polymetallic pollution (e.g. Cd, Zn) derived from the Decazeville basin, is a model system for studies on metal transfer from watersheds to the ocean. The relationship between historical records (~50 years) of Ag concentrations in sediment cores from the Lot River, upstream (Ag: 0.3 mg/kg) and downstream (Ag: up to 7 mg/kg) of the Decazeville basin and those of Cd constitutes evidence of a common source and transport/settlement processes due to industrial activities until 1986. High particulate Ag (AgP: 260 mg/kg) and dissolved Ag (AgD: 1,260 ng/l) concentrations in the Riou-Mort River were attributed to current leaching and erosion of slag heaps by rainwater. Those concentrations were 2 to 3 orders of magnitude greater than typical values in the Gironde watershed. However, the Riou-Mort River contribution to the Garonne River Ag fluxes (AgD: 0.008-0.041 t/a; AgP: 0.306-2.44 t/an; 1999-2009) remained low (AgP: <11%; AgD: <6%). The Garonne River provided the quasi totality (63-83%) of Ag inputs to the estuary, mainly in its particulate form (96±2%). The regional geochemical background (AgP/ThP=0.026) was useful to estimate (i) the natural contribution (20-65%) to total AgP fluxes and (ii) the anthropogenic specific fluxes of AgP (15±10 g/kmÂČ/a and 0.24±0.16 g/hab/a) in the Garonne watershed (La RĂ©ole). In the estuarine salinity, chloro-complexation desorbed ~60% of AgP, causing maximalum AgD concentrations (6-8 ng/l) at salinity 15-25 (addition to the dissolved phase). This quantity was similar to the potentially bioavailable or reactive fraction (i.e. extracted by HCl 1 M). The first estimations of net fluxes suggested that 50-80% of the Ag annual export to the coast occurred in the dissolved phase (0.64-0.89 t/a in 2008 and 0.56-0.77 t/a in 2009). Even if the ionic form Ag+ (the main form in freshwater) is considered as the most bioavailable form, Ag accumulation in estuarine organisms (oysters, shrimps and eels) reflected the higher exposition pressure in brackish water. In-situ caging of European Eels (recommended species for the biosurvey of aquatic systems; European Water Framework Directive) in key sites of the Gironde Estuary during 3 months, highlighted the direct and trophic pathways of Ag contamination at the environmental level. The historical record of Ag contamination of the Gironde Estuary oysters (1979-2007, French Mussel Watch, RNO) indicated that the Decazeville basin was a major Ag source until ~1988. However, the maximum Ag accumulation in oysters after 1993 (from ~40 to more than 100 mg/kg, dry weight) suggested an increasing contribution of additional and contemporary Ag sources like photography, cloud seeding (30-63 kg/a) or Toulouse and Bordeaux wastewater effluents (42-57 kg/a). This work is a basis for future work on Ag (including nanoparticles) cycles and related risks in aquatic systems (quantification, transfer and toxicity)

    Silver : sources, transfer and bioaccumulation : case of the Gironde fluvio-estuarine system

    No full text
    Les rejets d’argent (Ag) dans l’environnement liĂ©s Ă  l’exploitation miniĂšre aux diverses applications industrielles (e.g. bijouterie, mĂ©decine, photographie, Ă©lectronique et plus rĂ©cemment les nanotechnologies) font de Ag un polluant historique et Ă©mergent, dont les transferts et les effets dans les milieux aquatiques sont largement sous-documentĂ©s. Ce travail prĂ©sente un premier bilan des sources, du transfert et de la bioaccumulation de Ag dans le systĂšme fluvio-estuarien de la Gironde. Le continuum Lot-Garonne-Gironde, connu pour une pollution polymĂ©tallique (e.g. Cd, Zn) provenant du bassin de Decazeville, est un systĂšme modĂšle pour l’étude des transferts mĂ©talliques du continent Ă  l’ocĂ©an. Les enregistrements des signaux historiques (~50 ans) de Ag dans les sĂ©diments du Lot en amont (Ag : 0,3 mg/kg) et en aval (Ag : jusqu’à 7 mg/kg) du bassin de Decazeville sont similaires Ă  ceux de Cd, indiquant des sources et des processus de transport/dĂ©pĂŽt communs liĂ©s Ă  l’histoire miniĂšre et industrielle jusqu’en 1986. Le lessivage et l’érosion actuels des terrils provoquent localement des concentrations en Ag particulaire (AgP : 260 mg/kg) et dissous (AgD : 1260 ng/l) dans la riviĂšre Riou-Mort qui sont 2 Ă  3 ordres de grandeur supĂ©rieures aux valeurs typiques. MalgrĂ© ces fortes concentrations, la contribution du Riou-Mort aux flux de Ag de la Garonne (AgD : 0,008 Ă  0,041 t/an ; AgP : 0,306 Ă  2,44 t/an ; 1999-2009) reste faible (AgP : <11% ; AgD : <6%). La Garonne transporte l’essentiel (63-83%) des apports en Ag Ă  l’estuaire principalement sous forme particulaire (96±2%). La dĂ©termination du bruit de fond gĂ©ochimique rĂ©gional (AgP/ThP=0,026) a permis d’évaluer (i) la contribution naturelle (20% Ă  65%) aux flux totaux en AgP et (ii) les flux anthropiques spĂ©cifiques de AgP (15±10 g/kmÂČ/an et 0,24±0,16 g/hab/an) Ă  l’échelle du bassin versant de la Garonne (La RĂ©ole). Dans l’estuaire salin, la dĂ©sorption par les ions chlorures libĂšre ~60% de AgP vers la colonne d’eau (addition), provoquant des concentrations maximales en AgD (6-8 ng/l) Ă  salinitĂ© 15-25. La fraction en Ag dĂ©sorbĂ© correspond Ă  la fraction potentiellement biodisponible ou rĂ©active (i.e. extractible par HCl 1 M). Ainsi, les premiĂšres estimations des flux nets indiquent que l’export annuel de Ag vers le domaine cĂŽtier est Ă  50-80% liĂ© Ă  la phase dissoute (0,64 Ă  0,89 t/an en 2008 et 0,56 Ă  0,77 t/an en 2009). Bien que plus biodisponible sous forme ionique Ag+ (dominante en eau douce), l’accumulation de Ag dans les organismes estuariens (huĂźtres, crevettes et anguilles) reflĂšte la pression d’exposition supĂ©rieure en eau saumĂątre. L’exposition in situ d’anguilles europĂ©ennes, espĂšce recommandĂ©e pour la biosurveillance du milieu dans le cadre de la Directive Cadre sur l’Eau, dans des cages Ă  diffĂ©rents sites clĂ© de l’estuaire pendant 3 mois, a mis en Ă©vidence les voies directes et trophiques de la contamination en Ag Ă  des niveaux de contamination environnementaux. L’enregistrement historique de la contamination en Ag des huĂźtres de la Gironde (1979-2007, RNO, Ifremer) indique que le bassin de Decazeville a Ă©tĂ© la source majoritaire en Ag jusqu’en ~1988. Cependant, l’accumulation maximale de Ag dans ces bivalves aprĂšs 1993 (de ~40 Ă  plus de 100 mg/kg, poids sec) rĂ©vĂšle une contribution croissante de sources additionnelles et contemporaines en Ag comme la photographie, l’ensemencement des nuages (30 Ă  63 kg/an) ou encore les rejets des eaux usĂ©es urbaines de Toulouse et de Bordeaux (42 et 57 kg/an). Ce travail constitue une base nĂ©cessaire Ă  l’étude des rejets du cycle de Ag (y compris les nanoparticules) dans le milieu aquatique (quantification, transfert et toxicitĂ©) et des risques associĂ©s.Silver (Ag) emissions into the environment from former mining activities and various industrial applications (e.g. jewellery, medicine, photography, electronic products and more recently nanotechnology) make Ag both a historic and an emergent pollutant for which information on its transfer and toxicity in aquatic system are scarce. This work provides a first assessment of Ag sources, transfer and bioaccumulation in the Gironde fluvial-estuarine system. The Lot-Garonne-Gironde River continuum, known for its polymetallic pollution (e.g. Cd, Zn) derived from the Decazeville basin, is a model system for studies on metal transfer from watersheds to the ocean. The relationship between historical records (~50 years) of Ag concentrations in sediment cores from the Lot River, upstream (Ag: 0.3 mg/kg) and downstream (Ag: up to 7 mg/kg) of the Decazeville basin and those of Cd constitutes evidence of a common source and transport/settlement processes due to industrial activities until 1986. High particulate Ag (AgP: 260 mg/kg) and dissolved Ag (AgD: 1,260 ng/l) concentrations in the Riou-Mort River were attributed to current leaching and erosion of slag heaps by rainwater. Those concentrations were 2 to 3 orders of magnitude greater than typical values in the Gironde watershed. However, the Riou-Mort River contribution to the Garonne River Ag fluxes (AgD: 0.008-0.041 t/a; AgP: 0.306-2.44 t/an; 1999-2009) remained low (AgP: <11%; AgD: <6%). The Garonne River provided the quasi totality (63-83%) of Ag inputs to the estuary, mainly in its particulate form (96±2%). The regional geochemical background (AgP/ThP=0.026) was useful to estimate (i) the natural contribution (20-65%) to total AgP fluxes and (ii) the anthropogenic specific fluxes of AgP (15±10 g/kmÂČ/a and 0.24±0.16 g/hab/a) in the Garonne watershed (La RĂ©ole). In the estuarine salinity, chloro-complexation desorbed ~60% of AgP, causing maximalum AgD concentrations (6-8 ng/l) at salinity 15-25 (addition to the dissolved phase). This quantity was similar to the potentially bioavailable or reactive fraction (i.e. extracted by HCl 1 M). The first estimations of net fluxes suggested that 50-80% of the Ag annual export to the coast occurred in the dissolved phase (0.64-0.89 t/a in 2008 and 0.56-0.77 t/a in 2009). Even if the ionic form Ag+ (the main form in freshwater) is considered as the most bioavailable form, Ag accumulation in estuarine organisms (oysters, shrimps and eels) reflected the higher exposition pressure in brackish water. In-situ caging of European Eels (recommended species for the biosurvey of aquatic systems; European Water Framework Directive) in key sites of the Gironde Estuary during 3 months, highlighted the direct and trophic pathways of Ag contamination at the environmental level. The historical record of Ag contamination of the Gironde Estuary oysters (1979-2007, French Mussel Watch, RNO) indicated that the Decazeville basin was a major Ag source until ~1988. However, the maximum Ag accumulation in oysters after 1993 (from ~40 to more than 100 mg/kg, dry weight) suggested an increasing contribution of additional and contemporary Ag sources like photography, cloud seeding (30-63 kg/a) or Toulouse and Bordeaux wastewater effluents (42-57 kg/a). This work is a basis for future work on Ag (including nanoparticles) cycles and related risks in aquatic systems (quantification, transfer and toxicity)

    IntĂ©rĂȘt du dosage de la protĂ©ine S-100ß au cours de l'hĂ©morragie sous-arachnoĂŻdienne

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    Le vasospasme cĂ©rĂ©bral est une complication majeure de l'hĂ©morragie sous-arachnoĂŻdienne (HSA). MalgrĂ© les progrĂšs du monitorage multimodal, il reste difficile de dĂ©tecter les consĂ©quences ischĂ©miques du rĂ©trĂ©cissement artĂ©riel. Nous avons Ă©valuĂ© l'intĂ©rĂȘt du dosage de la protĂ©ine S-100ß, marqueur biologique de souffrance du tissu cĂ©rĂ©bral, dans la dĂ©tection de l'ischĂ©mie cĂ©rĂ©brale au cours du vasospasme, ainsi que son association avec les scores de gravitĂ© et le pronostic neurologique. 48 patients consĂ©cutifs adressĂ©s pour HSA ont Ă©tĂ© inclus prospectivement. Un prĂ©lĂšvement sanguin artĂ©riel pour dosage de S-100ß Ă©tait rĂ©alisĂ© Ă  l'admission, puis toutes les 48 heures pendant 10 jours. 11 patients ont eu des dosages rĂ©pĂ©tĂ©s artĂ©riels (A) et veineux jugulaires (Vj) permettant le calcul d'un gradient jugulo-artĂ©riel (Vj-A/Vj ; %), et 10 patients ont Ă©galement eu des dosages dans le LCR (DVE). Un tiers des patients ont dĂ©veloppĂ© un vasospasme. Nous avons observĂ© une relation positive entre la concentration artĂ©rielle initiale et les scores de gravitĂ© (p < 0.05), et un pronostic neurologique dĂ©favorable Ă  1 mois (GOS, p < 0.05). L'Ă©tude de la cinĂ©tique artĂ©rielle de la protĂ©ine S-100ß pendant 10 jours a objectivĂ© une baisse rĂ©guliĂšre de sa concentration chez les patients ne dĂ©veloppant pas de vasospasme (p < 0.05), tandis qu'elle ne baissait pas chez les patients dĂ©veloppant un vasospasme. Le gradient jugulo-artĂ©riel Ă©tait de 9 % (0-20) Ă  J1-J2, et tendait Ă  s'Ă©largir vers 20 % (0-37) entre J3 et J4 ( = 0.05). Les concentrations initiales dans le LCR Ă©taient 100 Ă  1000 fois supĂ©rieures aux concentrations dans le sĂ©rum, et Ă©taient corrĂ©lĂ©es Ă  la gravitĂ© neurologique et au pronostic. La libĂ©ration de la protĂ©ine est liĂ©e Ă  la gravitĂ© des lĂ©sions cĂ©rĂ©brales initiales, et Ă  l'apparition de lĂ©sions tissulaires secondaires. La cinĂ©tique artĂ©rielle est diffĂ©rente selon la survenue ou non d'un vasospasme. Le suivi des concentrations plasmatiques de la protĂ©ine S-100ß peut venir complĂ©ter le monitorage multimodal dans la dĂ©tection de l'ischĂ©mie au cours de l'HSAPARIS7-Xavier Bichat (751182101) / SudocPARIS-BIUM (751062103) / SudocSudocFranceF

    Multi‐residue analysis of 44 pharmaceutical compounds in environmental water samples by solid‐phase extraction coupled to liquid chromatography‐tandem mass spectrometry

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    International audienceA solid‐phase extraction combined with a liquid chromatography‐tandem mass spectrometry analysis has been developed and validated for the simultaneous determination of 44 pharmaceuticals belonging to different therapeutic classes (i.e., antibiotics, anti‐inflammatories, cardiovascular agents, hormones, neuroleptics, and anxiolytics) in water samples. The sample preparation was optimized by studying target compounds retrieval after the following processes: i) water filtration, ii) solid phase extraction using Waters Oasis HLB cartridges at various pH, and iii) several evaporation techniques. The method was then validated by the analysis of spiked estuarine waters and wastewaters before and after treatment. Analytical performances were evaluated in terms of linearity, accuracy, precision, detection, and quantification limits. Recoveries of the pharmaceuticals were acceptable, instrumental detection limits varied between 0.001 and 25 pg injected and method quantification limits ranged from 0.01 to 30.3 ng/L. The precision of the method, calculated as relative standard deviation, ranged from 0.3 to 49.4%. This procedure has been successfully applied to the determination of the target analytes in estuarine waters and wastewaters. Eight of these 44 pharmaceuticals were detected in estuarine water, while 26 of them were detected in wastewater effluent. As expected, the highest values of occurrence and concentration were found in wastewater influent

    Distribution of parasites in their second intermediate host, the cockle Cerastoderma edule: community heterogeneity and spatial scale

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    We studied the spatial heterogeneity of infection of the marine bivalve Cerastoderma edule (cockle) by trematode parasites at 5 different scales in Banc d'Arguin, France. At the km-scale, the communities of trematodes differed among stations in terms of species composition and specific abundance. Infection heterogeneity was likely due to the occurrence of the definitive host and the conditions of transmission (water parameters). At the 100 m scale, trematode species richness was similar among stations, but specific trematode abundances differed. The most significant variable in terms of explaining trematode infection heterogeneity was the presence of the first intermediate host. At the 10 m scale, the distance at which parasite abundance diminished varied according to trematode species. When an intense source of trematode larvae (cercariae) emission was suspected, this abundance was maintained within ca. 20 m. Outside this area, parasite abundance progressively dropped. We found a higher aggregation in parasite distribution at the 100 m scale than at the 10 m scale using a community aggregation measure. At the cm-scale, the parasite species richness was similar in all cockles but parasite abundance differed in relation to distance when the parasites were shed by a sedentary host compared to a motile host. Observed differences of infection could also be due to intrinsic factors (life history, immune system) as suggested by an experimental infestation where cockles challenged in similar conditions displayed different parasite loads. We demonstrated that high heterogeneity of parasite infection in cockles should be taken into account in studies concerning the role of parasites in ecosystems

    Simultaneous determination of 42 pharmaceuticals in seafood samples by solvent extraction coupled to liquid chromatography–tandem mass spectrometry

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    International audienceAn efficient and sensitive analytical method based on liquid chromatography–tandem mass spectrometry (LC–MS/MS) has been developed and validated for the simultaneous determination of 42 pharmaceuticals belonging to different therapeutic classes (i.e. antibiotics, analgesics, anti-inflammatories, cardiovascular agents, anxiolytics and human indicators) in seafood samples. The very simple sample preparation included analytes extraction with acidified methanol, concentration by evaporation and filtration of the final extract prior to LC–MS/MS analysis. Analytical performances were evaluated in muscles of four commercial species (hake, red mullet, sole and shrimp) and showed good recoveries at two spiked concentration levels, with relative standard deviations below 45%. Limits of quantification ranged from 0.1 to 40.2 ng/g. This procedure has been successfully applied to the determination of the target analytes in seafood collected from the Bay of Biscay (Southern France) and 4 of these 42 pharmaceuticals were detected at low ng/g levels, suggesting a very limited contamination
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