Éditeur(s) : HAL CCSD Wiley
Résumé : International audience
The embryonic development in Chione cancellata, from fertilization to straighthinge D-stage veliger larva, occurs in 24 h at 251C. Transmission (TEM) and scanning (SEM) electron microscopy show that morphogenetic processes result in a gastrula with two depressions, 4 h after fertilization (T014 h). Two hours later, one depression, located at the animal pole, develops into an open cave, the floor of which becomes the shell field, characterized by scarce microvilli, located below the lower face of the prototrochal pad. The invagination located at the vegetal pole is characterized by regular microvilli and constitutes the digestive tract. At T018 h, the late gastrula differentiates into a typical motile trochophore, possessing a well-developed prototroch delimiting anterior and posterior embryonic regions. At T019h, the shell field, located between the prototroch and the telotroch, appears as a saddle-shaped region with a wrinkled surface extending on both sides of the embryo, establishing bilateral symmetry. From TEM observations, the apical surface of the underlying cells possesses a modified glycocalyx featuring a dense pellicle overlapping the cells of the shell field. At T0112 h, the prototroch is displaced toward the anterior region by outgrowth of the shell material. TEM views show that the wrinkled surface observed with SEM corresponds to the periostracum, attached dorsally to the hinge and ventrally to the cells of the future mantle edge. At T0115 h, an alveolar matrix of proteinaceous material, which could contain calcite crystals, appears between the periostracum and the mantle. At T0124 h, prodissoconch I formation is completed and the D-stage larvae possess a calcified shell. At this stage of development, only one mantle fold is present, representing the outer fold. The periostracumsecreting cells are in contact with the marginal cells of the velum. This functional velum is composed of four bands of cilia. Our TEMobservations confirm previous descriptions of the velum ciliary bands obtained only from SEM analyses, such as described in other bivalves. The apical sense organ and the digestive tract are poorly developed. From observations at the ultrastructural level of shell differentiation in C. cancellata, we propose a new interpretation of shell differentiation, including hinge and ligament for bivalves as opposed to that described for gastropods.
ISSN: 1077-8306

hal-00755283
https://hal.univ-antilles.fr/hal-00755283
DOI : 10.1111/j.1744-7410.2006.00036.x

Éditeur(s) : HAL CCSD American Institute of Physics
Résumé : International audience
Laser-induced periodic surface structures (LIPSS) were formed on Cu/Si or Cu/glass thin films using Nd:YAG laser beam (40 ps, 10Hz, and 30mJ/cm2). The study of ablation threshold is always achieved over melting when the variation of the number of pulses increases from 1 to 1000. But the incubation effect is leading to reduce the threshold of melting as increasing the number of laser pulse. Also, real time reflectivity signals exhibit typical behavior to stress the formation of a liquid phase during the laser-processing regime and helps to determine the threshold of soft ablation.Atomic Force Microscopy (AFM) analyses have shown the topology of the micro-crater containing regular spikes with different height. Transmission Electron Microscopy (TEM) allows finally to show three distinguished zones in the close region of isolated protrusions. The central zone is a typical crystallized area of few nanometers surrounded by a mixed poly-crystalline and amorphous area. Finally, in the region far from the protrusion zone, Cu film shows an amorphous structure. The real time reflectivity, AFM, and HR-TEM analyses evidence the formation of a liquid phaseduring the LIPSS formation in the picosecond regime. VC 2015 AIP Publishing LLC
ISSN: 0003-6951

hal-01226065
https://hal.archives-ouvertes.fr/hal-01226065
DOI : 10.1063/1.4935413

Éditeur(s) : HAL CCSD Wiley-Blackwell
Résumé : International audience
Garnet growth in high-pressure, mafic garnet granulites formed by dehydration melting of hornblende-gabbronorite protoliths in the Jijal complex (Kohistan palaeo-island arc complex, north Pakistan) was investigated through a microstructural EBSD-SEM and HRTEM study. Composite samples preserve a sharp transition in which the low-pressure precursor is replaced by garnet through a millimetre-sized reaction front. A magmatic foliation in the gabbronorite is defined by mafic-rich layering, with an associated magmatic lineation defined by the shape-preferred orientation (SPO) of mafic clusters composed of orthopyroxene (Opx), clinopyroxene (Cpx), amphibole (Amp) and oxides. The shape of the reaction front is convoluted and oblique to the magmatic layering. Opx, Amp and, to a lesser extent, Cpx show a strong lattice-preferred orientation (LPO) characterized by an alignment of [001] axes parallel to the magmatic lineation in the precursor hornblende-gabbronorite. Product garnet (Grt) also displays a strong LPO. Two of the four < 111 > axes are within the magmatic foliation plane and the density maximum is subparallel to the precursor magmatic lineation. The crystallographic relationship < 111 >(Grt)//[001](Opx,Cpx,Amp) deduced from the LPO was confirmed by TEM observations. The sharp and discontinuous modal and compositional variations observed at the reaction front attest to the kinetic inhibition of prograde solid-state reactions predicted by equilibrium-phase diagrams. The P-T field for the equilibration of Jijal garnet granulites shows that the reaction affinities are 5-10 kJ mol.(-1) for the Grt-in reaction and 0-5 kJ mol.(-1) for the Opx-out reaction. Petrographic and textural observations indicate that garnet first nucleated on amphibole at the rims of mafic clusters; this topotactic replacement resulted in a strong LPO of garnet. Once the amphibole was consumed in the reaction, the parallelism of [001] axes of the mafic-phase reactants favoured the growth of garnet crystals with similar orientations over a pyroxene substrate. These aggregates eventually sintered into single-crystal garnet. In the absence of deformation, the orientation of mafic precursor phases conditioned the nucleation site and the crystallographic orientation of garnet because of topotaxial transformation reactions and homoepitaxial growth of garnet during the formation of high-pressure, mafic garnet-granulite after low-pressure mafic protoliths.
ISSN: 0263-4929

hal-00411323
https://hal.archives-ouvertes.fr/hal-00411323
DOI : 10.1111/J.1525-1314.2008.00789.x

Éditeur(s) : HAL CCSD Cerimes
Résumé : L'ensemble des articles est archivé sur ArchiveTémaTice. Les actes sont aussi accessibles sur le site du colloque http://www.cerimes.fr/colloquefrancomexicain
Les textes qui composent ces actes ont été présentés à l'occasion du premier colloque franco-mexicain en sciences de la communication, organisé par la Asociación mexicana en Ciencias de la comunicación (AMIC) et la Société Française des Sciences de l'Information et de la Communication (SFSIC), à Mexico, du 8 au 10 avril 2002.

Les médias classiques: radio, télévision (8 avril 2002)
Introduction . La coopération scientifique bilatérale et l'interculturel dans l'activité de recherche, Bruno Ollivier
La recherche française sur le média et les discours télévisuels: éléments pour un bilan prospectif, Guy Lochard
Parcours de la programmation télévisée au Mexique, Florence Toussaint
El regimen de la television hertziana en Mexico, Claudia I. Garcia Rubio
La question de l'éthos et du genre en communication politique, Simone Bonnafous
L'exposition de la vie privée dans les médias, André Vitalis

Identités, culture, communication (9 avril 2002)
Reconfiguraciones cimunicativas de la socialidad y reencantamientos de la communication identidad, Jesus Martin-Barbero
Identité, culture et communication, Jean François Tetu
Las organizaciones civiles en las radiodifusoras comerciales, Dr. José Cisneros E.
Les SIC et l'altérité: démarches d'une recherche sur la Chine. réflexions épitstémologiques sur les analyses de corpus à base communicationnelles de langue et de culture non-maternelles, Dominique Colomb
Transicion, reforma del estado y medios de comunicacion en Mexico, Dr. Javier Esteinou Madrid
Medios masivos y formacion psicosocial, Enrique Guinsberg

Technologies d'information et de communication ( 10 avril 2002)
Quoi de nouveau dans la recherche française en informatique et communication ? Bernard Miege
Convergencia tecnologica: perspectivas de investigacion en Mexico, Delia Crovi Druetta
Medias, technologies et public: la notion de projet au cœur d'une éventuelle médiation, Claire Noy
La formacion de profesores de educacion superior en el uso de la computadora y la internet. reflexioànes sobre el tema, Luz Maria Garay Cruz
Vers un retour à une lecture non linéaire, Schmidt C. T, Roxin I.(), Mercier D, Hufschmitt B. & Cotten J.-P
NTIC et éducation à distance. Le cas d'Edusat au Mexique face au cas français, Norma Veronica Fernandez Arriaga.
Les sciences de l'éducation et les sciences de la communication en dialogue: à propos des médias et des technologies éducatives, Geneviève Jacquinot-Delaunay
Internet et Intranet dans les organisations "un scénario récurrent", Jean-Antoine Corbalan
De l'université virtuelle au campus numérique : simple effet de traduction ou changement de paradigme, Françoise Thibault
Competencias mediacionales de los sujetos en programas educativos en entornos digitales, Maria Elena Chan Nunez
Le journal quotidien sur le Web. L'identité éditoriale au risque du formatage, Annelise Touboul
Conclusion, Carmen Gomez-Mont
Premier colloque franco-mexicain de sciences de la communication
Mexico, France

Droits : info:eu-repo/semantics/OpenAccess
ISBN : http://www.cerimes.education.fr
edutice-00000362
https://edutice.archives-ouvertes.fr/edutice-00000362
https://edutice.archives-ouvertes.fr/edutice-00000362/document
https://edutice.archives-ouvertes.fr/edutice-00000362/file/actes.pdf

Éditeur(s) : HAL CCSD Elsevier
Résumé : International audience
Experimentally Assisted Molecular Modelling (EAMM) is an original approach for predicting the structure of organic micro-crystals and deducing their habit in the presence of various solvents and additives. It is applied here in the case of n-octylamino-nitrobenzoxadiazole (nOA-NBD), a fluorescent compound. This general approach is first of all described and validated by its blind application to three known and closely-related crystals. Then, the whole process is applied to predict the molecular crystal generated by n-octylamino-NBD, including the molecule conformation, its structure (cell parameters, molecular packing, X-ray powder diagrams) and its theoretical plus actual habits in the presence of a solvent (p-xylene) and two additives (acetic acid and n-dodecane). The conformation of the predicted molecule is validated by comparison with two similar molecules embedded in observable crystals. Then, the choice between two proposed structures (with the same energy and two equiprobable packings) is based on the comparison between experimental and re-computed X-ray powder diffraction diagrams, and also on the interpretation of an actual TEM image in the light of the proposed cell parameters. This choice is confirmed by the comparison between the vapour-grown face development (proposed by the BFDH or the attachment energy models) and the actual face development in a pure solvent. Finally, the actual habit deduced from comparing the crystal attachment energy with the adsorption energy of solvent or additive molecules is validated by SEM images of NBD micro-crystals in presence of the solvent alone or in presence of both additives. In conclusion, the EAMM approach appears to be a decisive tool for quickly simulating structural and habit properties of the molecular crystals, accessible or not by experimentation. Thus, a numerical selection of molecules becomes possible in view of deriving organic materials with predetermined properties, such as the fluorescence properties of the compound considered in the present study.
ISSN: 0022-0248

hal-00857894
https://hal.archives-ouvertes.fr/hal-00857894
DOI : 10.1016/j.jcrysgro.2011.07.035

Éditeur(s) : HAL CCSD BioMed Central
Résumé : International audience
Background: Myosin II (or Myosin Heavy Chain II, MHCII) is a family of molecular motors involved in the contractile activity of animal muscle cells but also in various other cellular processes in non-muscle cells. Previous phylogenetic analyses of bilaterian MHCII genes identified two main clades associated respectively with smooth/non-muscle cells (MHCIIa) and striated muscle cells (MHCIIb). Muscle cells are generally thought to have originated only once in ancient animal history, and decisive insights about their early evolution are expected to come from expression studies of Myosin II genes in the two non-bilaterian phyla that possess muscles, the Cnidaria and Ctenophora. Results: We have uncovered three MHCII paralogues in the ctenophore species Pleurobrachia pileus. Phylogenetic analyses indicate that the MHCIIa /MHCIIb duplication is more ancient than the divergence between extant metazoan lineages. The ctenophore MHCIIa gene (PpiMHCIIa) has an expression pattern akin to that of ``stem cell markers'' (Piwi, Vasa...) and is expressed in proliferating cells. We identified two MHCIIb genes that originated from a ctenophore-specific duplication. PpiMHCIIb1 represents the exclusively muscular form of myosin II in ctenophore, while PpiMHCIIb2 is expressed in non-muscle cells of various types. In parallel, our phalloidin staining and TEM observations highlight the structural complexity of ctenophore musculature and emphasize the experimental interest of the ctenophore tentacle root, in which myogenesis is spatially ordered and strikingly similar to striated muscle formation in vertebrates. Conclusion: MHCIIa expression in putative stem cells/proliferating cells probably represents an ancestral trait, while specific involvement of some MHCIIa genes in smooth muscle fibres is a uniquely derived feature of the vertebrates. That one ctenophore MHCIIb paralogue (PpiMHCIIb2) has retained MHCIIa-like expression features furthermore suggests that muscular expression of the other paralogue, PpiMHCIIb1, was the result of neofunctionalisation within the ctenophore lineage, making independent origin of ctenophore muscle cells a likely option.
ISSN: 1471-2148

hal-01544486
https://hal.archives-ouvertes.fr/hal-01544486
DOI : 10.1186/1471-2148-12-107

Éditeur(s) : HAL CCSD Elsevier
Résumé : International audience
Despite many studies, our understanding of silica precipitation from natural waters remains limited, in particular for geothermal waters. Here we present a detailed study on the kinetics of silica polymerization as a function of fluid temperature and pH using high-temperature (250-260 °C) seawater-derived geothermal fluids as those discharged from the Bouillante geothermal site.We monitored the on-site decrease in monomeric silica concentration(initial SiO2 concentration of about 600 mg/l)with time using the molybdenum blue spectrophotometric method on samples of separated water collected from the high-pressure separator at 167 °C and cooled to 25, 50, 75, and 90 °C and for pH values ranging from 5 to 8. During all these experiments, only silica polymerization was observed, with the formation of colloidal particles in suspension in the solutions. No scaling of amorphous silica was formed. The collected data were after modeled in order to determine the useful kinetic parameters for predicting and preventing amorphous silica precipitation in the production wells during fluid exploitation in the specific context of Bouillante. Results under the investigated experimental conditions show that the kinetics of silica precipitation is affected more strongly by pH than by temperature change. The reaction in the acidic Bouillante solution begins with a transition period that significantly decreases the kinetics of silica polymerization. Modeling the experimental data indicates that the silica polymerization up to the state of equilibrium is characterized by a 2nd-order kinetic law relative to dissolved silica; this could indicate that the polymerization is controlled mainly by the formation of dimers. However, the first hour of the experiments is better characterized by a 4th-order kinetic law, suggesting more complex polymerization reactions in the initial stage with the formation of nanocolloidal particles containing 3 to 4 monomers. In both cases, the corresponding kinetics rate constant k is linearly dependent on pH for pH between 5 and 7. The activation energy Ea for the overall reaction, calculated using the Arrhenius equation under the considered pH and temperature conditions, ranges between 41±9.8 and 54±9.6 kJ/mol. To complete this work, the colloid particles formed at the end of the kinetics experiments were extracted and analyzed by SEM and TEM microscopy, X-ray Diffraction and the BET method. Results show that the size of the colloids increase and their specific surface decrease with increasing pH and are thus dependent on pH. Globally, our work provides a reliable database for understanding silica polymerization kinetics in natural geothermal brines or geologic waters characterized by a near neutral pH and moderate dissolved silica concentrations.
ISSN: 0009-2541

hal-01403092
https://hal-brgm.archives-ouvertes.fr/hal-01403092
DOI : 10.1016/j.chemgeo.2016.08.031

Éditeur(s) : HAL CCSD Elsevier
Résumé : International audience
We analyzed twelve fault gouge samples from the Bogd fault in south-western Mongolia to understand the origin and behavior of clay minerals. The investigation relies on x-ray powder diffraction (XRD), scanning electron microscopy (SEM), transmission electron microscopy (TEM) and high energy synchrotron x-ray diffraction methods to investigate microstructure and preferred orientation. Smectite (montmorillonite), illite-smectite mixed layers, illite-mica and kaolinite are the major clay components, in addition to quartz and feldspars, which are present in all samples. The observations suggest that the protoliths and the fault rocks were highly altered by fluids. The fluid-rock interactions allow clay minerals to form, as well as alter feldspars to precipitate kaolinite and montmorillonite. Thus, newly formed clay minerals are heterogeneously distributed in the fault zone. The decrease of montmorillonite component of some of the highly deformed samples also suggests that dehydration processes during deformation were leading to illite precipitation. Based on synchrotron x-ray diffraction data, the degree of preferred orientation of constituent clay minerals is weak, with maxima for (001) ranging from 1.3 to 2.6 multiples of a random distribution (m.r.d). Co-existing quartz and feldspars have random orientation distributions. Microstructure and texture observations of the gouges from the foliated microscopic zone, alternating with micrometric isotropic clay-rich area, also indicate that the Bogd fault experienced brittle and ductile deformation episodes. The clay minerals may contribute to a slip weakening behavior of the fault.
ISSN: 0191-8141

insu-00667194
https://hal-insu.archives-ouvertes.fr/insu-00667194
DOI : 10.1016/j.jsg.2011.10.006

Éditeur(s) : HAL CCSD Wiley
Résumé : International audience
Strombus gigas and Strombus pugilis are threatened species and aquaculture represents a good alternative solution to the fishing. In this study, we highlighted the intracellular digestion process in the digestive gland of two Strombidae species, S. gigas and Strombus pugilis, by the cytochemical characterization of two lysosomal enzymes: acid phosphatase and arylsulfatase. In order to check the efficiency of artificial food digestion, we onducted the characterization on freshly collected, tarved and artificially fed individuals of S. pugilis. TEM observations of digestive gland sections from freshly collected individuals of both species revealed the resence of acid phosphatase and arylsulfatase activity mostly located in the apical third of digestive cells. Both enzymes were also detected in artificially fed individuals. In response to the starvation, acid phosphatase is not produced anymore by digestive cells, while arylsulfatase is still present. To our knowledge, this is the first cytochemical validation of intracellular digestion of artificial food in Strombidae. This study highlights the intracellular digestion of artificial food developed for Strombidae aquaculture. Moreover, we have shown that the lysosomal activity could be used as a feed index.
ISSN: 1059-910X

hal-00743013
https://hal.univ-antilles.fr/hal-00743013
DOI : 10.1002/jemt.22074

Éditeur(s) : Université des Antilles Études caribéennes
Résumé : À travers les expositions universelles récentes et passées et plus particulièrement les expositions de Milan 2015 et de Port-au-Prince 1949, nous rappelons que cette pratique touristique du voyage d’agrément dans une grande ville remonte au xixe siècle, elle accompagne les origines de notre tourisme moderne, tout en devenant un instrument de géopolitique et de marketing touristique de première importance pour les villes et les pays hôtes. Les expositions peuvent être considérées comme un levier urbanistique, mais aussi un moyen de faire voyager et de comprendre notre monde à travers un système de représentation des identités locales et mondiales proposant toujours une mise en valeur de la découverte scientifique et de l’expérience culturelle à travers les pavillons nationaux. Ces manifestations géantes reposent sur une mise en scène et en récit à partir d’un thème universel questionnant généralement le concept du développement durable et de l’attractivité touristique renouvelée de la destination. Notre analyse porte sur la plus récente des expositions universelles et une exposition oubliée appartenant à l’aire culturelle des caraïbes permettant de dégager trois dynamiques associant le tourisme de méga-événement et l’utopie des voyages initiatiques, à savoir : les expositions universelles se réinventent et retrouvent un certain succès de fréquentation impliquant une redéfinition des champs et des usages d’une utopie contrariée. Faire voyager est un acte à la fois scénographique et symbolique à travers le pavillon impliquant des artifices et des déclinaisons de plus en plus numériques, la quête de cette pratique durable du voyage se confronte à son héritage et à son souvenir à différentes échelles et temporalités.  
Through the recent and past universal exhibitions and more particularly the world’s fair of Milan 2015 and Port-au-Prince 1949, we recall that this tourist practice of the pleasure trip in a large city dates back to the xixth century, it accompanies the origins of Our modern tourism, while becoming an instrument of geopolitics and tourist marketing of prime importance to cities and host countries. Exhibitions can be seen as an urban lever, but also a way to make travel and understand our world through a system of representation of local and global identities that always emphasizes scientific discovery and cultural experience through the national pavilion. These giant events are based on a staging and narrative based on a universal theme generally questioning the concept of sustainable development and the renewed attractiveness of the destination. Our analysis focuses on the most recent of the universal exhibitions and a forgotten exhibition belonging to the cultural area of the Caribbean, which reveals three dynamics associating mega-event tourism with the utopia of initiatory journeys, namely: reinvent and regain a certain success of frequentation implying a redefinition of the fields and uses of a disrupted utopia; to make travel is an act both scenographic and symbolic through the pavilion involving artifices and more and more digital declensions, the quest for this sustainable practice of travel is confronted with its heritage and its memory at different scales and temporalities.
A través de las exposiciones universales recientes y pasados y, especialmente, la Feria de Milán en 2015 y Puerto Príncipe en 1949, recordamos que esta práctica de turismo de viaje de placer a una gran ciudad se remonta al siglo xix, que acompaña a los orígenes de turismo moderno, mientras que convertirse en un instrumento geopolítico y comercialización del turismo de las principales ciudades y países anfitriones. Las exposiciones pueden considerarse una palanca urbana, sino también una manera de viajar y entender nuestro mundo a través de un sistema de representación de las identidades locales y globales que todavía ofrece el desarrollo de los descubrimientos científicos y la experiencia cultural a través pabellones nacionales. Estas manifestaciones gigantes basados en una puesta en escena y la narrativa de un tema universal en general, cuestionando el concepto de desarrollo sostenible y renovada atractivos turísticos del destino. Nuestro análisis se centra en las últimas exposiciones universales y una exposición olvidado que pertenecen a la zona cultural del Caribe para identificar tres dinámico entre el turismo mega-evento y la utopía de los viajes iniciáticos, a saber: las exposiciones universales reinventar y encontrar un cierto éxito de asistencia que implica una redefinición de campos y utiliza una utopía alterada, para viajar es un acto tanto teatral y simbólico a través del pabellón y declinaciones cada vez más digitales, las la búsqueda de este viaje práctica sostenible se enfrenta a su artificialidad y su memoria en diferentes escalas y marcos de tiempo.
Europe
Caraïbes
Italie
Haïti
France
Milan
Port-au-Prince
New York
Osaka

Droits : info:eu-repo/semantics/openAccess
urn:doi:10.4000/etudescaribeennes.11239
http://journals.openedition.org/etudescaribeennes/11239

Éditeur(s) : HAL CCSD Springer Verlag
Résumé : International audience
A San Carlos olivine polycrystal has been deformed under uppermost mantle conditions, by compression at 900 °C, at a strain rate of 1.1 × 10−5 s−1, under a confining pressure of 300 MPa, using the Paterson press. Transmission electron tomography of dislocations has been performed by scanning transmission electron microscopy, by conventional transmission electron microscopy using the weak-beam dark-field technique, associated with precession or not, in order to determine the glide planes of [001] screw dislocations. This recent technique is the most suitable one since most [001] dislocations exhibit straight screw segments due to the high lattice friction on this character at low temperature. We find that [001] dislocations glide in (100), (010) and {110} as already reported, but also more unexpectedly in {120} and {130}. We show that at 900 °C, [001] {110} glide is dominant in polycrystals. We have, however, noted and characterized numerous cross-slip events in the specimen.
ISSN: 0342-1791

hal-01054330
https://hal.archives-ouvertes.fr/hal-01054330
DOI : 10.1007/s00269-014-0665-1

Éditeur(s) : HAL CCSD Springer Verlag
Résumé : The core structures of dislocations in diopside have been calculated within the Peierls model, which assumes a planar core. 1/2 < 110 > dislocations can dissociate into two collinear partial dislocations. We show that [001] glide is very difficult in (010) and that a non-collinear dissociation of [001](100) (modelled within a Peierls-Nabarro-Galerkin approach) makes glide equally easy in (100) and {110}. A widely spread core structure corresponding to a low lattice friction has been found for [100](010) and [010](100) dislocations which is not supported by mechanical data and, together with TEM observations, suggests that another, probably non-planar core structure is possible for these dislocations.
ISSN: 0342-1791

hal-00558238
https://hal.archives-ouvertes.fr/hal-00558238
DOI : 10.1007/s00269-010-0370-7

Éditeur(s) : HAL CCSD Elsevier
Résumé : International audience
A comprehensive inventory of global biodiversity would be greatly improved by automating methods for species delimitation. The Automatic Barcode Gap Discovery method, the Poisson tree processes algorithm and the Generalized mixed Yule coalescent model have been proposed as means of increasing the rate of biodiversity description using single locus data. We applied these methods to explore the diversity within the Aglaopheniidae, a hydrozoan family with many species widely distributed across tropical and tem perate oceans. Our analyses revealed widespread cryptic diversity in this family, almost half of the morpho species presenting several independent evolutionary lineages, as well as support for cases of synonymy. For two common species of this family, Lytocarpia brevirostris and Macrorhynchia phoenicea, we compared the outputs to clustering analyses based on microsatellite data and to nuclear gene phylo genies. For L. brevirostris, microsatellite data were congruent with results of the species delimitation methods, revealing the existence of two cryptic species with Indo Pacific distribution. For M. phoenicea, all analyses confirmed the presence of two cryptic species within the South Western Indian Ocean. Our study suggests that the diversity of Aglaopheniidae might be much higher than assumed, likely related to low dispersal capacities. Sequence based species delimitation methods seem highly valuable to reveal cryptic diversity in hydrozoans; their application in an integrative framework will be very useful in describing the phyletic diversity of these organisms.
ISSN: 1055-7903

hal-01359407
https://hal.archives-ouvertes.fr/hal-01359407
https://hal.archives-ouvertes.fr/hal-01359407/document
https://hal.archives-ouvertes.fr/hal-01359407/file/Postaire-etal2016MolPhylEvol_sp_delim_hydraires_HAL.pdf
DOI : 10.1016/j.ympev.2016.08.013

Éditeur(s) : HAL CCSD Optical Society Optical Society - SOA Publishing
Résumé : International audience
We show that the canonical single frequency sarcomeric SHG intensity pattern (SHG-IP) of control muscles is converted to double frequency sarcomeric SHG-IP in preserved mdx mouse gastrocnemius muscles in the vicinity of necrotic fibers. These double frequency sarcomeric SHG-IPs are often spatially correlated to double frequency sarcomeric two-photon excitation fluorescence (TPEF) emitted from Z-line and I-bands and to one centered spot SHG angular intensity pattern (SHG-AIP) suggesting that these patterns are signature of myofibrillar misalignement. This latter is confirmed with transmission electron microscopy (TEM). Moreover, a good spatial correlation between SHG signature of myofibrillar misalignment and triad reduction is established. Theoretical simulation of sarcomeric SHG-IP is used to demonstrate the correlation between change of SHG-IP and -AIP and myofibrillar misalignment. The extreme sensitivity of SHG microscopy to reveal the submicrometric organization of A-band thick filaments is highlighted. This report is a first step toward future studies aimed at establishing live SHG signature of myofibrillar misalignment involving excitation contraction defects due to muscle damage and disease.
ISSN: 2156-7085

hal-00952823
https://hal.archives-ouvertes.fr/hal-00952823
https://hal.archives-ouvertes.fr/hal-00952823/document
https://hal.archives-ouvertes.fr/hal-00952823/file/boe-5-3-858_002.pdf
DOI : 10.1364/BOE.5.000858

Éditeur(s) : HAL CCSD Wiley
Résumé : International audience
Background information. Marine nematodes belonging to the Stilbonematidae (Desmodoridae) family are described as living in obligatory association with sulfur-oxidizing chemoautotrophic ectosymbionts. The symbiotic bacteria carrying out this chemosynthesis should contain elemental sulfur in periplasmic granules as sulfur granules of chemoautotrophic endosymbionts described in various marine invertebrates. Results. Based on TEM analyses, extracellular bacteria surrounding Eubostrichus dianae possess these spherical periplasmic granules. Few investigative techniques can be used to identify elemental sulfur S8 such as EDXS (energy dispersive X-ray spectroscopy) and EELS (electron energy loss spectroscopy) associated with cryo-fixation of the sample to avoid sulfur loss. These techniques are time consuming, expensive and require technical skills. Raman microspectrometry applied to the analysis of E. dianae allowed us to detect elemental sulfur S8 and confirmed the location of these sulfur clusters in the bacterial coat. In the same way, Raman spectrometry was positively applied to the endosymbiotic bivalve Codakia orbicularis, suggesting that this technique can be used to characterize sulfur in ecto- as well as in endo-symbiotic sulfur-oxidizing bacteria. Conclusions. As Raman spectrometry can be used on living organisms (without preliminary fixation) without sample damage and preserving the molecular structure of the sulfur (denatured during chemical fixation) it represents a very well-adapted investigative tool for biologists. This technique therefore permits us to detect quickly and easily (in a few seconds and on entire living animals) the presence of sulfur compounds in the symbiotic nematode.
ISSN: 0248-4900

hal-00753017
https://hal.univ-antilles.fr/hal-00753017

Éditeur(s) : HAL CCSD Elsevier
Résumé : International audience
In order to estimate the seismic anisotropy of subducted crust, polycrystalline samples of KA1Si(3)O(8) K-lingunite (25% of the total subducted transformed sediments), have been synthesized and deformed under the temperature and pressure conditions of the subducted slabs. Transmission electron microscopy (TEM) characterizations of the recovered samples reveal that the microstructures are clearly dominated by [001] glide involving screw dislocations. For this reason, only {100} could be identified as glide planes, the question of [001] slip on {110} remains open. Few 1/2 < 111 > dislocations were observed gliding on {110} planes, which implies that 1/2 < 111 > {110} is a harder slip system than those involving [001] slip. The occurrence of sub-grain boundaries suggests that diffusion and climb might be active under these conditions.;To assess the texture of polycrystalline K-lingunite, the crystal preferred orientations (CP05) were calculated using visco-plastic self-consistent (VPSC) polycrystalline plasticity model in simple shear using the slip systems identified by TEM. Finally, the seismic properties of K-lingunite aggregates were calculated from the CPO and single crystal elasticity tensor. K-lingunite is predicted to have a high seismic anisotropy, which could combine constructively with one of the stishovite (same proportion as K-lingunite at the transition zone depth ranges).
ISSN: 0031-9201

hal-00534050
https://hal.archives-ouvertes.fr/hal-00534050
DOI : 10.1016/j.pepi.2010.06.013

Éditeur(s) : Université des Antilles Études caribéennes
Résumé : L’objectif de ce numéro de la Revue Etudes Caribéennes est d’ouvrir une réflexion sur le concept de luxe, d’investir le luxe dans tous ses états. Il s’agit d’interroger les fondements du luxe, de la théorie à la matérialité, de la fabrication à la consommation, entre distinction provocante et esthétisation des genres de vie. Dans le cadre de ce numéro thématique, le luxe est envisagé dans une approche pluridisciplinaire, de la philosophie à la sociologie, de l’économie à l’aménagement du territoire … Les contributions pourront aborder le luxe sous un angle spécifique (économie du luxe, le luxe à travers l’histoire), traiter une dimension particulière du luxe, à travers un produit emblématique ou la construction de territoires singuliers (les territoires du luxe). Une attention particulière sera portée à l’industrie du luxe avec ses grandes marques et ses logiques de création et de production. Enfin, le luxe existe à travers la construction de ses légendes qui sont autant de signes distinctifs qui stimulent les consommateurs occasionnels et exclusifs. Les thématiques privilégiées seront : 1. Le concept du luxe à travers les différents champs disciplinaires (« consommation ostentatoire », « distinction provocante », « esthétisation des comportements », « marché-jugement ») 2. Le luxe dans le temps (entre sacré et ostentatoire, la signification du luxe, les mythes du luxe) 3. Le luxe et la création (les objets qui consacrent le luxe, de la création à la construction de la légende) 4. L’industrie du luxe (haute couture, joaillerie, spiritueux … griffes et grandes marques du luxe) 5. L’économie du luxe (le luxe en période de crise, l’économie des singularités) 6. Le luxe dans le champ du tourisme (l’hôtellerie de luxe, les destinations du tourisme de luxe) 7. La durabilité du luxe, entre renouvellement et éternité This issue of “Revues Etudes Caribéennes” aims to reflect upon the concept of luxury, to invest the luxury in all its states. It comes to question the foundations of luxury, from the theory to the materiality, from the manufacture to the consumption, between provocative distinction and aesthetization in all walk of life. Within the context of this thematic issue, luxury is envisaged a multidisciplinary approach, ranging from philosophy to sociology, from the economy to the development of the territory... Imputs may approach luxury a specific angle (economics of luxury, the luxury throughout history). They can treat a particular dimension of luxury, through an emblematic product or construction of luxury territories. Special attention will be paid to the luxury industry with its brands and its logic of creation and production. Finally, luxury exist through the construction of its legends which are formed from many distinctive indicators that stimulate both the casual and the exclusive consumers. The priorities themes will be: 1. The concept of luxury across the different disciplinary fields ('conspicuous consumption', 'provocative distinction", 'aestheticization of behaviour', and 'market-judgement') 2. Luxury in time (between the sacred and ostentatious, the meaning of luxury, the myths of luxury) 3. Luxury and Creation (objects dedicated to luxury, from the creation to the construction of the legend) 4. Luxury industry (haute couture, jewelry, spirits... claws and luxury brands) 5. The economy of luxury (luxury during economic crisis, and the economy of singularities) 6. Luxury in tourism (luxury hotels, luxury destinations) 7. The sustainability of luxury, between renewal and eternity El objetivo de este número de la Revista Estudios Caribeños es de abrir una reflexión sobre el concepto de lujo, de invertir el lujo en todos sus estados. Se trata de interrogar los fundamentos del lujo, de la teoría a la materialidad, de la fabricación a la consumición, entre distinción provocativa y formas de esteticismo de la vida. En este número temático, el lujo está considerado en un enfoque pluridisciplinar, de la filosofía a la sociología, de la economía a planificación del territorio…Las contribuciones podrán abordar el lujo sobre un ángulo específico (economía del lujo, el lujo a través de la historia), tratar una dimensión particular del lujo, a través de un producto emblemático o la construcción de territorios singulares (los territorios del lujo). Una atención particular será llevada a la industria del lujo con sus grandes marcas y lógicas de creación y de producción. En fin, el lujo existe a través de la construcción de sus leyendas que son tantos signos distintivos que estimulan los consumidores ocasionales y exclusivos. Los temas privilegiados serán: 1. El concepto del lujo a través de los diferentes campos disciplinarios (« consumación ostentosa », « distinción provocadora », « estetización de comportamientos, «juicio del mercado « ) 2. El lujo en el tiempo (entre sagrado y ostentatorio, el significado del lujo, los mitos del lujo) 3. El lujo y la creación (los objetos que consagran el lujo, de la creación a la construcción de la leyenda) 4. La industria del lujo (alta costura, joyería, espiritoso… uñas y grandes marcas del lujo) 5. La economía del lujo (el lujo en período de crisis, la economía de las singularidades) 6. El lujo en el campo del turismo (la hostelería de lujo, las destinaciones del turismo de lujo) 7. La duración del lujo, entre renovación y eternidad

Droits : info:eu-repo/semantics/openAccess
urn:doi:10.4000/etudescaribeennes.7310
http://journals.openedition.org/etudescaribeennes/7310

Éditeur(s) : HAL CCSD Wiley-Blackwell
Résumé : International audience
Here, the first description of an epsilon sulfur-oxidizing bacterium from sulfide-rich sediments of marine mangrove in Caribbean is reported. According to TEM, this new strain contains intracytoplasmic large internal sulfur granules as confirmed by EDXS analyses performed using ESEM. The sulfur distribution obtained for this sulfur-oxidizing bacterial strain allows to conclude that elemental sulfur is formed as an intermediate oxidation product and stored intracellularly. According to conventional SEM observations, bacterial cells are ovoid, extremely motile by lophotrichous flagella. Phylogenetic analyses based on the analysis of partial sequence of 16S rDNA confirm that such bacterial strain belongs to the Thiovulum cluster and could be a representative of a new species in this poorly studied genus of sulfur-oxidizing free-living bacteria. Thus, reduced sediment of marine mangrove represents sulfide-rich environment sustaining development of both gamma and epsilon sulfur-oxidizing Proteobacteria
ISSN: 0378-1097

hal-01682113
https://hal.univ-antilles.fr/hal-01682113
DOI : 10.1093/femsle/fnx172

Éditeur(s) : HAL CCSD
Résumé : Croton urucurana Baillon (Euphorbiaceae), plant species popularly known in Brazil as “sangra-d’água”, is commonly found in Mato Grosso do Sul State (midwestern Brazil), where its latex is popularly used to treat several types of cancer. Despite the ethnopharmacological significance of the species, no phytochemical or cytotoxic studies of its latex have been published. In this context, the aim of the present study was to assess the cytotoxic activity of crude extracts, fractions and isolated compound from the latex of C. urucurana and to investigate the effects of crourorb A1 on the viability, apoptosis, cell cycle and cell migration of human hepatocarcinoma cell lines (Huh-7). Also, we have evaluated the viability of Huh-7 cells treated with crourorb A1 in 3D collagen gels. The cytotoxicity was detected using the sulforhodamine B (SRB) assay against six human cancer cells lines and one nontumor NIH/3T3 cell line (murine fibroblast). Studies on the mechanism of cell death of crourorb A1 were conducted in different test systems in vitro. The bioactive ethyl acetate phase obtained from the latex of C. urucurana afforded a novel cyclic peptide, [1−9-NαC]-crourorb A1, that proved active against NCIADR/ RES (ovary, multidrug-resistance phenotype) cells with the same potency as doxorubicin (positive control) and inactive up to the highest concentration tested against nontumor NIH/3T3 cells (GI50 = > 250 μg/mL). Crourorb A1 treatment decreases the cell viability of Huh-7 at dose and time dependent manner associated with induction of apoptosis by caspase 3/7 activation and increasing expression of pro-apoptotic proteins: Bak, Bid, Bax, Puma, Bim, and Bad and clived-caspase3 protein. The JNK/MAP pathway is involved in this induced cell death. Crourorb A1 effect is also associated with G2/M phase cell cycle arrest. In parallel, we observed that crourorb A1 treatment resulted in an increase of cyclin-dependent kinase (CDK1), cyclin B1 and cyclin D1 expressions. A significant reduction of Huh-7 cells migration by crourorb A1 can be assessed and we also show that cells grown on 3D collagen gels exhibited increased resistance to crourorb A1 when compared to 2D cell culture.
Croton urucurana Baillon (Euphorbiaceae), est une plante très connue et utilisée en médecine traditionnelle au Brésil, la «sangra-d’água» retrouvée dans l'État du Mato Grosso do Sul (région Centre-Ouest du Brésil). Son latex est abondamment utilisé en médecine traditionnelle dans le traitement de plusieurs types de cancer. En dépit de son importance ethnopharmacologique, on ne trouve aucune étude sur sa composition chimique ou sur sa potentielle activité anti-cancéreuse. L’objectif de ce travail a été d'évaluer l'activité cytotoxique des extraits totaux, fractions d’extraits et de molécules purifiées, isolées du latex de C. urucurana. Nous avons étudié plus particulièrement les effets du crourorb A1 sur la viabilité, l'apoptose, le cycle cellulaire et la migration de cellules issues de carcinome hépatocellulaire humaine (Huh-7). Nous avons également évalué l’effet du crourorb A1sur la viabilité des cellules Huh-7 cultivées dans les gels de collagène en 3D. L' activité cytotoxique ont été réalisées par le test à la sulforhodamine B sur six lignées cellulaire cancéreuses et sur une lignée cellulaire non cancéreuse de fibroblastes murins, les cellules NIH/3T3. L'étude phytochimique de la fraction ‘acétate d'éthyle’ du latex de C. urucurana bioguidé a permis d’obtenir un nouveau cyclopeptide que nous avons nommé [1-9-NαC]-crourorb A1. Le crourorb présente une cytotoxicité puissante sur la lignée cellulaire cancéreuse NCI-ADR/RES (ovaire, le phénotype de multirésistance) à un niveau équivalent à celle de la doxorubicine (témoin positif). Ce composé est de plus pratiquement inactif (GI50 = >250 μg/mL) sur la lignée non cancéreuse NIH/3T3. L'évaluation de la cytotoxicité in vitro du crourorb A1 (test wst1) sur les cellules Huh-7 a démontré que la viabilité des cellules est inhibée de manière dose et temps-dépendant. Nous avons mesuré une forte activation des caspases 3 et 7 et une nette augmentation de l’expression des protéines pro-apoptotiques (Bak, Bid, Bax, Puma, Bim et Bad) ainsi que de la caspase 3 clivée par le crourorb A1. Nous avons également déterminé que la voie de signalisation JNK-MAPkinase semble nécessaire à l’induction de la mort cellulaire des cellules Huh-7 traitées au crourorb A1. Le crourob A1 induit un arrêt du cycle cellulaire en phase G2/M. En parallèle, les expressions de la cycline-dépendante kinase CDK1, des cyclines B1 et D1 sont augmentées après traitement au crourorb A1. De plus, le crourorb A1 a un effet inhibiteur significatif de la migration des cellules Huh-7, en présence ou absence de mitomycine C. Nous avons également confirmé, l’effet inhibiteur du crourob A1 sur la viabilité des cellules Huh7 cultivées en 3D dans les gels de collagène 1 et démontré que les cellules cultivées en 3D semblent plus résistantes au crourorb A1 par rapport aux cultures en monocouche 2D.
Croton urucurana Baillon (Euphorbiaceae) é uma espécie arbórea conhecida popularmente no Brasil como “sangra d´água”, comumente encontrada no estado de Mato Grosso do Sul, onde seu látex tem sido utilizado na medicina popular no tratamento de vários tipos de câncer. Apesar de sua importância etnofarmacológica, não há relatos de estudos relacionados à sua composição química ou atividades anticâncer na literatura. Nesse contexto, o objetivo do presente estudo foi avaliar a atividade citotóxica de extratos, fases, frações e da substância isolada do látex de C. ururucurana e investigar os mecanismos celulares e moleculares in vitro responsáveis pela citotoxicidade da substância isolada considerando seu potencial apoptótico e influência sobre a progressão do ciclo celular em uma linhagem de hepatocarcinoma celular humano (Huh-7), bem como, os efeitos desta substância sobre a migração e viabilidade de células Huh-7 cultivadas em geis de colágeno em 3D. O ensaio de citotoxicidade in vitro foi realizado com o corante sulforrodamina B (SRB) em seis linhagens de células neoplásicas humanas e uma linhagem de células não neoplásicas NIH/3T3 (fibloblasto murinho). Os estudos de mecanismos de ação com crourorb A1 foram conduzidos em diferentes sistemas-teste in vitro. O estudo fitoquímico biomonitorado da fase bioativa acetato de etila do látex de C. urucurana resultou no isolamento de um novo ciclopeptídeo denominado [19-NαC]-crourorb A1, que apresentou potente atividade citotóxica frente à linhagem de células neoplásicas NCI-ADR/RES (ovário com fenótipo de resistência a múltiplos fármacos), com a mesma potência que a doxorrubicina (controle positivo), e foi inativa até a maior concentração testada (GI50 = >250 μg/mL) frente à linhagem de células não neoplásicas 3T3. A exposição de células Huh-7 ao crourorb A1 resultou em uma diminuição da viabilidade celular de maneira dose e tempo-dependentes. Nós observamos um aumento da atividade de caspases 3 e 7 e um aumento da expressão de proteínas próapoptóticas (Bak, Bid, Bax, Puma, Bim e Bad) e caspase 3 clivada após tratamento com crourorb A1. Além disso, observamos que a via de sinalização celular MAP/JNK foi necessária para induzir a morte celular em células Huh-7 tratadas com crourorb A1. Os efeitos de crourorb A1 foram também associados com o acúmulo de células na fase G2/M do ciclo celular. Em paralelo, as expressões da cinase dependente da ciclina (CDK1), ciclina B1 e ciclina D1 foram aumentadas após tratamento com crourorb A1. Foi demonstrado também o envolvimento de crourorb A1 na redução da migração de células Huh-7 cultivadas na presença e ausência de mitomicina C. A avaliação da viabilidade de células Huh-7 cultivadas em geis de colágeno em 3D apontou uma maior resistência destas células ao crourorb A1 quando comparadas com a cultura de células em 2D.
https://tel.archives-ouvertes.fr/tel-01478286

NNT : 2016REN1B010
tel-01478286
https://tel.archives-ouvertes.fr/tel-01478286
https://tel.archives-ouvertes.fr/tel-01478286/document
https://tel.archives-ouvertes.fr/tel-01478286/file/DE-MATOS-CANDIDO-BACANI-Priscila.pdf

Éditeur(s) : Université des Antilles Études caribéennes
Résumé : El presente artículo tiene como objetivo, valorar la conducta ética del profesional en turismo como elemento incidente en el servicio innovador y sostenible de la actividad turística. Es un análisis crítico ya que en él se da una relación constructiva de la teoría y la práctica, de lo que es y el deber ser de las ejecuciones de los profesionales del turismo. Para su abordaje se procedió a un estudio documental, basado en la revisión bibliográfica de material actualizado sobre el tema en cuestión, llegando a la conclusión de que toda innovación turística, desde la identificación y conversión de recurso turístico hasta su puesta en valor como producto turístico, requiere de un sistema de información turística, de una tecnología. Además el turismo sostenible es una estrategia que promueve el desarrollo de comunidades con riquezas paisajísticas, culturales, ambientales, etc. La práctica ética del profesional en turismo es determinante en la calidad del servicio hotelero innovador y en esa medida se contribuye a que éste sea sostenible en el tiempo.
This article aims, assess the ethical conduct of professional tourism as an element incident innovative and sustainable tourism service. It is a critical analysis since it constructive relationship of theory and practice, of what is and what ought to be the executions of tourism professionals is given. For your approach proceeded to a desk study, based on a literature review of current on the subject matter material concluding that all tourism innovation, from identification and conversion of resource to its value as a tourism product requires a tourist information system, a technology. Furthermore sustainable tourism is a strategy that promotes the development of communities Scenic, cultural, environmental wealth, etc. The practice of professional ethics in tourism is crucial to the quality of service and innovative Hotelier this measure helps to make it sustainable over time.

Droits : info:eu-repo/semantics/openAccess
urn:doi:10.4000/etudescaribeennes.9452
http://journals.openedition.org/etudescaribeennes/9452