Consulta: subjectFacets:"Mantle"
Registros recuperados: 10
Data/hora: 08/06/2024 13:38:37

New insights into the origin and distribution of the DUPAL isotope anomaly in the Indian Ocean mantle from MORB of the Southwest Indian Ridge
Provedor de dados: 5
Autores: Meyzen, Cm; Ludden, Jn; Humler, E; Luais, B; Toplis, Mj; Mevel, C; Storey, M.
We report new Sr, Nd, and Pb isotope data for Mid-Ocean Ridge Basalts (MORB) dredged between 35 and 69 degrees E along a similar to 4100 km section of the Southwest Indian Ridge (SWIR), which is one of the slowest spreading ridges of the global mid-ocean ridge system ( full rate of 16 mm yr(-1)). The SWIR appears isotopically more heterogeneous than other mid-ocean ridges over similar length scales and comparable sampling density. Isotopic variations are generally independent of ridge segmentation, and the degree of heterogeneity decreases from west to east. This decrease in heterogeneity correlates with the observed increase in axial depth and decrease in crustal thickness, commonly attributed to decreasing mantle potential temperature. Data for the...
Tipo: Text
Palavras-chave: Southwest Indian Ridge; MORB; Isotopes; Indian Ocean; Lower crust; Mantle.
Ano: 2005
URL: https://archimer.ifremer.fr/doc/00232/34286/32655.pdf

Ecophysiologie de la reproduction chez l'huître creuse, Crassostrea gigas
Provedor de dados: 5
Autores: Pouvreau, Stephane; Lepennec, M.
The reproductive cycle of Megathura crenulata was documented and quantification of oocyte lipid reserves with lipo-specific stains was explored in both this species and in Crassostrea gigas. The necessity of providing food to female broodstock C. gigas in spring was re-evaluated, because subsequent larval and post-larval rearing performance was not affected by broodstock starvation during conditioning. Developmental study of the organs responsible of particle processing in C. gigas allowed the identification of critical stages related to the ontogenesis of each organ, as well as a better understanding of the evolution of these organs, highly-modified in the Ostreidae. Ciliary type identification and mucocyte mapping from post-larval to adult stage showed...
Tipo: Text
Palavras-chave: Mucocytes; Mantle; Gill; Larvae postlarvae juveniles; Feeding; Crassostrea gigas; Megathura crenulata; Development; Reproduction; Mucocytes; Manteau; Branchie; Larves post larves juvéniles; Alimentation; Crassostrea gigas; Megathura crenulata; Développement; Reproduction.
Ano: 2006
URL: http://archimer.ifremer.fr/doc/2006/rapport-1867.pdf

Chlamydia-like organisms in ctenidia and mantle cells of the Japanese oyster Crassostrea ggias from the French Atlantic coast
Provedor de dados: 5
Autores: Renault, Tristan; Cochennec, Nathalie.
Grossly visible lesions of the ctenidia and occasional mortalities in Japanese oyster Crassostrea gigas from the Atlantic French coast were reported in 1992-1993. From August 1992 to March 1993, 235 living oysters were collected to determine the cause of tissue lesions and mortalities. Microscopical examination of fixed, stained sections revealed that 53 2% of these oysters had ctenidia and mantle lesions associated with irregular basophllic and Feulgen positive cytoplasmic inclusion bodies. Ultrastructurally, the infectious agent was a chlamydia-like organism. Indirect fluorescent and peroxidase conjugated antibody tests suggested that this agent might share common antigens with the prokaryotic agent Chlamydia psittaci, strain ovis
Tipo: Text
Palavras-chave: Mantle; Ctenidia; Chlamydia like organisms; Pacific oyster; Crassostrea gigas.
Ano: 1995
URL: http://archimer.ifremer.fr/doc/1995/publication-2896.pdf

Bases biologiques de la production de deux Mollusques d'intérêt économique: reproduction chez Megathura crenulata, reproduction et développement chez Crassostrea gigas
Provedor de dados: 5
Autores: Cannuel, Rozenn.
The reproductive cycle of Megathura crenulata was documented and quantification of oocyte lipid reserves with lipo-specific stains was explored in both this species and in Crassostrea gigas.  The necessity of providing food to female broodstock C. gigas in spring was re-evaluated, because subsequent larval and post-larval rearing performance was not affected by broodstock starvation during conditioning.  Developmental study of the organs responsible of particle processing in C. gigas allowed the identification of critical stages related to the ontogenesis of each organ, as well as a better understanding of the evolution of these organs, highly-modified in the Ostreidae. Ciliary type identification and mucocyte mapping from post-larval to adult stage showed...
Tipo: Text
Palavras-chave: Mucocytes; Mantle; Gill; Larvae postlarvae juveniles; Feeding; Crassostrea gigas; Megathura crenulata; Development; Reproduction; Mucocytes; Manteau; Branchie; Larves post larves juvéniles; Alimentation; Crassostrea gigas; Megathura crenulata; Développement; Reproduction.
Ano: 2005
URL: http://archimer.ifremer.fr/doc/2005/these-1371.pdf

Origine et circulation des fluides dans les sédiments des marges. Contribution de l'hélium et du méthane dans la compréhension des processus. Étude de 2 zones actives
Provedor de dados: 5
Autores: Chaduteau, Carine.
Fluid migration is a very important process in marine sediments on margins. Studying fluids is fundamental to constrain the energy potential of margins. Methane is the predominant gas in marine sediments, deriving primarily from the degradation of organic matter. However methane could be also generated through the serpentinization of mantle rocks underlying the sedimentary cover in some specific geodynamical settings. One way to test this hypothesis is to use helium isotopes, which are known to be powerful tracers of the fluid-mantle interaction. To this purpose, a new method has been developed for the sampling and the quantitative extraction of dissolved helium from sediment pore-waters. During the Zairov2 and Vicking cruises, samples were collected in...
Tipo: Text
Palavras-chave: Mantle; Serpentinization; Advection; Mud volcano; Pockmark; Methane; Helium; Fluid; Margin; Manteau; Serpentinisation; Advection; Volcan de boue; Pockmark; Méthane; Hélium; Fluide; Marge.
Ano: 2008
URL: http://archimer.ifremer.fr/doc/2008/these-3724.pdf

Mantle histology, histochemistry and ultrastructure of the pearl oyster Pinctada margaritifera (L.)
Provedor de dados: 5
Autores: Jabbour-zahab, Roula; Chagot, Dominique; Blanc, François; Grizel, Henri.
The edge and isthmus of the mantle of Pinctada margaritifera (Mollusc, Bivalvia) were studied using light and electron microscopy from a morphological and histochemical point of view. Six areas with several subareas were differentiated in the mantle edge. One of these areas is similar to the epithelium isthmus, Trials to elucidate the nature of the pigment responsible for the black colour of the shell and pearl indicate a melanin-like material. Possible functions of the distinctive epithelial areas in Pinctada margartifera mantle are discussed according to available data on the secretion of organic matrix of the shell, protein sclerotization and deposition of crystals in some pearl-forming molluscs. Three different epithelial areas in the outer mantle edge...
Tipo: Text
Palavras-chave: Bivalvia; Mollusc; Pinctada margaritifera; Pigment; Ultrastructure; Structure; Mantle; Bivalves; Mollusques; Pinctada margaritifera; Pigment; Ultrastructure; Structure; Manteau.
Ano: 1992
URL: http://archimer.ifremer.fr/doc/1992/publication-2770.pdf

Sur une tumeur du manteau de Crassostrea gigas (Thunberg)
Provedor de dados: 5
Autores: Comps, Michel; Quiros-ramos, Hernando; Razet, Daniel.
A tumor of the mantle has been found in Crassostrea gigas coming from oyster-bed of Marennes-Oleron basin. Near the tumor, the shells show a malformation. Microscopic examination shows the connective nature of this tumor, it was covered with an epithelium and consisted of several sinuses filled with leucocytes.
Tipo: Text
Palavras-chave: Shell; Tumor; Mantle; Crassostrea gigas.
Ano: 1973
URL: http://archimer.ifremer.fr/doc/1973/publication-2150.pdf

Crustal structure of a super-slow spreading centre: a seismic refraction study of Mohns Ridge, 72 degrees N
Provedor de dados: 5
Autores: Klingelhofer, Frauke; Geli, Louis; Matias, Luis; Steinsland, N; Mohr, J.
A series of eight high-resolution seismic refraction profiles from the ultra-slow spreading (16 mm yr(-1) full spreading rate) Mohns Ridge in the Norwegian-Greenland Sea has been treated with modern inversion methods. The profiles were shot parallel to the ridge at an off-axis distance of 0-135 km corresponding to crustal ages of 0-22 Ma. The resulting models are constrained by synthetic seismograms and gravity modelling.The crustal thickness in all profiles is well below the global average for typical oceanic crust, and shows a high variability with a mean thickness of 4.0 +/- 0.5 km. This is mainly due to a very thin and variable lower crustal layer (Layer 3). Generally, the crust is thicker beneath basement highs and thinner beneath basins, implying...
Tipo: Text
Palavras-chave: Seismic refraction; Oceanic crust; Mohns Ridge; Mantle.
Ano: 2000
URL: https://archimer.ifremer.fr/doc/2000/publication-681.pdf

Different secretory repertoires control the biomineralization processes of prism and nacre deposition of the pearl oyster shell
Provedor de dados: 5
Autores: Marie, Benjamin; Joubert, Caroline; Tayale, Alexandre; Zanella-cleon, Isabelle; Belliard, Corinne; Piquemal, David; Cochennec-laureau, Nathalie; Marin, Frederic; Gueguen, Yannick; Montagnani, Caroline.
Mollusca evolutionary success can be attributed partly to their efficiency to sustain and protect their soft body with an external biomineralized structure, the shell. Current knowledge of the protein set responsible for the formation of the shell microstructural polymorphism and unique properties remains largely patchy. In Pinctada margaritifera and Pinctada maxima, we identified 80 shell matrix proteins, among which 66 are entirely unique. This is the only description of the whole "biomineralization toolkit" of the matrices that, at least in part, is thought to regulate the formation of the prismatic and nacreous shell layers in the pearl oysters. We unambiguously demonstrate that prisms and nacre are assembled from very different protein repertoires....
Tipo: Text
Palavras-chave: Mantle; Mollusk shell matrix proteins; Proteome; Transcriptome; Evolution.
Ano: 2012
URL: http://archimer.ifremer.fr/doc/00118/22959/20922.pdf

The Lages diatremes: mineral composition and petrological implications
Provedor de dados: 42
Autores: Barabino,Giancarlo; Gomes,Celso B.; Traversa,Gianbosco.
Chemical data of heavy minerals from Lages diatremes in southern Brazil have been studied with the aim of characterizing the sample source(s). Three groups of minerals are recognized: I) aluminian-chromian pyroxene, pyrope garnet and chromian spinel, which represent disaggregated fragments of spinel, spinel+garnet and garnet facies peridotite; II) low-Cr aluminian pyroxene that occurs as megacrysts are high pressure phases (7-12 kb) being crystallized from an alkaline-like evolving magma; III) low-Cr aluminian diopside of crustal origin. Evidence of carbonatitic cryptic metasomatic enrichment is shown by clinopyroxenes of Groups I and II. The data do not support a kimberlitic affinity as it has been suggested for the diatremes. Rather, they are interpreted...
Tipo: Info:eu-repo/semantics/article
Palavras-chave: Brazil; Mantle; Clinopyroxene; Megacryst; Metasomatism.
Ano: 2007
URL: http://www.scielo.br/scielo.php?script=sci_arttext&pid=S0001-37652007000300010