Éditeur(s) : HAL CCSD Elsevier
Résumé : International audience
The mycotoxin alternariol (AOH), a frequent contaminant in fruit and grain, is known to induce cellular stress responses such as reactive oxygen production, DNA damage and cell cycle arrest. Cellular stress is often connected to autophagy, and we employed the RAW264.7 macrophage model to test the hypothesis that AOH induces autophagy. Indeed, AOH treatment led to a massive increase in acidic vacuoles often observed upon autophagy induction. Moreover, expression of the autophagy marker LC3 was markedly increased and there was a strong accumulation of LC3-positive puncta. Increased autophagic activity was verified biochemically by measuring the degradation rate of long-lived proteins. Furthermore, AOH induced expression of Sestrin2 and phosphorylation of AMPK as well as reduced phosphorylation of mTOR and S6 kinase, common mediators of signaling pathways involved in autophagy. Transmission electron microscopy analyzes of AOH treated cells not only clearly displayed structures associated with autophagy such as autophagosomes and autolysosomes, but also the appearance of lamellar bodies. Prolonged AOH treatment resulted in changed cell morphology from round into more star-shaped as well as increased β-galactosidase activity. This suggests that the cells eventually entered senescence. In conclusion, our data identify here AOH as an inducer of both autophagy and senescence. These effects are suggested to be to be linked to AOH-induced DSB (via a reported effect on topoisomerase activity), resulting in an activation of p53 and the Sestrin2-AMPK-mTOR-S6K signaling pathway.
ISSN: 0300-483X

hal-01117627
https://hal-univ-rennes1.archives-ouvertes.fr/hal-01117627
https://hal-univ-rennes1.archives-ouvertes.fr/hal-01117627/document
https://hal-univ-rennes1.archives-ouvertes.fr/hal-01117627/file/Autophagy%20and%20senescence_accepted.pdf
PUBMED : 25456271

Éditeur(s) : HAL CCSD American Geophysical Union (AGU)
Résumé : International audience
Sandbox modeling is used to study the deformation of accretionary wedges caused by the subduction of oceanic ridges. The first experiment incorporates a massive ridge within a sand wedge. The wedge thickens and shortens when the forward propagation of the basal decollement ceases. The wedge thickening results in taper change, reactivation of preexisting thrusts, and retreat of the frontal part of the sand wedge. Similar mechanisms may have affected some margins that have undergone ridge subduction such as the Tonga margin after the subduction of the oblique Louisville oceanic ridge. The second experiment shows the effects of an active basement thrust slice as it enters a subduction zone. This process may have happened in the eastern Nankai accretionary wedge. Initially, the wedge in this experiment behaved similarly to that of the first experiment. Rapidly the topographic slope changed, the wedge thickened above the basement slice generating a slope break in the topography; a deeper propagating accretionary wedge again characterized by a small taper developed. These results, when compared with observations made in the Eastern Nankai Trench, are in agreement with the past subduction of a basement thrust slice in this area.
ISSN: 0278-7407

hal-01261549
https://hal.archives-ouvertes.fr/hal-01261549
https://hal.archives-ouvertes.fr/hal-01261549/document
https://hal.archives-ouvertes.fr/hal-01261549/file/Lallemand_et_al-1992-Tectonics.pdf
DOI : 10.1029/92TC00637

Résumé : Herbácea de hasta 1 m de alto; tallos jóvenes pilosos. Hojas en pares o solitarias, de diferentes tamaños pero similares en forma, enteras o sinuado-dentadas, ovadas a ovado-lanceoladas, ápice acuminado, base atenuada. Inflorescencia internodal, racemosa o subumbelifera; corola blanca o lila, con una mancha obscura en la base de cada lóbulo. Fruto globoso de 4 a 7 mm de diámetro.
Herbacée pouvant atteindre 1 m de haut; tiges jeunes pileuses. Feuilles par paires ou solitaires, de différentes tailles mais de forme semblable, entières ou sinuo-dentées, ovées à ovo-lancéolées, à pointe acuminée et à base atténuée. Inflorescence internodale, en grappe ou subombellifère; corolle blanche ou couleur lilas, avec une tache sombre à la base de chaque lobe. Fruit arrondi de 4 à 7 mm de diamètre.
Anthers 1.7 mm or more in length; dull black or green mature fruit; calyx adhering to fruit; fruiting pedicels noticably deflexed; plants of highlands. Herb, up to 1 m high; young stems pilose.  Leaves in pairs or solitary, of different sizes but similar appearance, entire or sinuate-dentate, ovate to ovate-lanceolate; apex acuminate, base attenuate.  Inflorescences internodal, racemose or subumbellate; corolla white or lilac, with a dark spot at the base of each lobe.  Fruit globose, 4-7 mm in diameter.
Nativa de Centroamérica, crece en todo el trópico americano.
Originaire de l’Amérique centrale, présente dans l’ensemble de la zone tropicale américaine, mais jamais signalé aux Petites Antilles.
Native to Central America; grows

http://www.tramil.net/fototeca/plant328

Éditeur(s) : HAL CCSD
Résumé : Spermatogenesis in mammals is a complex biological function including cellular processes such as proliferation, meiosis and differentiation, aiming to the production of male gametes in the testis. If the seminiferous epithelium is well described in terms of organization and cellular morphology of cells that compose it, the processes by which undifferentiated diploid germ cells enter meiosis and give haploid cells that undergo many morphological transformations, are not fully decrypted. These processes rely on the coordinated and sequential expression of genes, including specific products for each stage of germ cell development These gene products are essential at each key stage of spermatogenesis. Transcriptomics since the 1990s, and proteomics since the 2000s have contributed to the improved. understanding of these mechanisms. A long term proteomic study aiming at characterizing the proteomes of Sertoli cells and germ cells, and a recent study that characterized and quantified the transcriptome of isolated rat testicular cells at high resolution using de novo sequencing of transcripts (RNA-Seq), have been the basis of my thesis work. The latter study showed the accumulation of long non-Coding RNAs (lncRNAs) and testicular unannotated transcripts (TUTs) at meiotic and post-Meiotic stages of spermatogenesis in the rat. In this context, my thesis work aimed at validating the coding potential of many genes expressed in germ cells using RNA-Seq combined with shotgun proteomics, a so-Called PIT (Proteomics Informed by transcriptomics) approach. In this approach, the protein sequences translated from the transcripts assembled by RNA-Seq in the different testicular cell types are integrated into a custom database of protein sequences used to query mass spectrometry data obtained from proteins of meiotic and post-Meiotic cells. The PIT approach showed that 69 TUTs or lncRNA (corresponding to 44 loci) code for proteins in meiotic cells and post meiotic cells, and we confirmed experimentally the meiotic and post-Meiotic expression for two new transcripts encoding for VAMP9, a protein of the SNARE family, and a new testicular enolase T-ENOL. The post-Meiotic expression of T-ENOL protein was confirmed by immunohistochemistry using a polyclonal antibody raised against the recombinant protein. This approach also allowed us to identify new isoforms of known proteins, specific to each stage of spermatogenesis. Germ cells and Sertoli cells maintain a dialogue which is necessary to the success of spermatogenesis and spermiogenesis. Another part of my work aimed at identifying membrane proteins, in germ cells and residual bodies, that may be involved in the dialogue between Sertoli cells and germ cells, using a ICPL relative quantification proteomic approach. The ICPL analysis enabled us to establish a list of 166 proteins whose expression is differential between pachytene spermatocytes, round spermatids and residual bodies. Their differential expression suggests that these proteins may play a role in spermiogenesis. Thanks to the Gene Ontology annotations, a list of 8 proteins with a putative role in signal transduction, cell recognition or differentiation, thus potentially involved in the dialogue between Sertoli and germ cells was drawn. In addition, I provided a first proteome of rat Sertoli cells, germ cells and residual bodies obtained by shotgun proteomics.
La spermatogenèse chez les mammifères est une fonction biologique complexe incluant des processus de prolifération cellulaire, de méiose et de différenciation uniques visant à la production des gamètes mâles au sein du testicule. Si l’épithélium séminifère est bien décrit sur le plan de son organisation et de la morphologie des cellules qui le composent, les processus par lesquels les cellules germinales diploïdes indifférenciées entrent en méiose pour donner ensuite des cellules haploïdes subissant par la suite de nombreuses transformations morphologiques, ne sont pas totalement décryptés. Ils reposent sur l’expression coordonnée et séquentielle de gènes dont les produits spécifiques de chaque stade de développement des cellules germinales sont essentiels aux étapes clés de la spermatogenèse. La transcriptomique depuis les années 1990 et la protéomique depuis les années 2000 ont contribué à l’amélioration de la connaissance de ces mécanismes. Une étude protéomique visant à caractériser par des approches systématiques et différentielles les protéomes des cellules de Sertoli et de la lignée germinale, et d’autre part une étude récente, réalisée dans notre unité, qui a permis de caractériser et de quantifier le transcriptome des cellules testiculaires isolées de rat en utilisant le séquençage de novo des transcrits (RNA-Seq), ont été à la base de mes travaux de thèse. Cette dernière étude a mis en évidence l’accumulation de longs ARNs non codants (lncRNAs) et de transcrits testiculaires non annotés (TUTs) aux stades méiotique et post- méiotique de la spermatogenèse chez le rat. Dans ce contexte, mon travail a consisté à valider le potentiel codant de nombreux gènes exprimés dans les cellules germinales par une approche dite PIT (Proteomics Informed by Transcriptomics) couplant protéomique Shotgun et RNA-Seq. Dans ce type d’approche, les séquences protéiques déduites des transcrits des différents types cellulaires, assemblés par RNA-Seq, sont intégrées dans une base personnalisée de séquences protéiques utilisée pour interroger les données de spectrométrie de masse obtenues à partir de protéines de cellules méiotiques et post-Méiotiques. L’approche PIT a permis de montrer que 69 TUTs ou lncRNA (correspondant à 44 loci) codent pour des protéines dans les cellules méiotiques et post méiotiques. L’expression post-Méiotique de deux nouveaux transcrits, l’un codant pour la protéine VAMP9, une protéine de la famille SNARE, et l’autre pour une nouvelle énolase T-ENOL a pu être confirmée. L’expression post-Méiotique de T-ENOL a été confirmée par immunohistochimie à l’aide d’un anticorps polyclonal produit contre la protéine recombinante. Cette approche nous a également permis d’identifier de nouvelles isoformes de protéines connues spécifiques de chaque stade de la spermatogenèse. Les cellules germinales et les cellules de Sertoli entretiennent le dialogue nécessaire au bon déroulement de la spermatogenèse. Une autre partie de mon travail a consisté à identifier des protéines membranaires des cellules germinales et des corps résiduels, susceptibles d’intervenir dans le dialogue entre les cellules de Sertoli et les cellules germinales, par une approche protéomique de quantification relative ICPL. Cette approche a permis d’établir une liste de 166 protéines différentiellement exprimées entre les spermatocytes pachytène, les spermatides rondes et les corps résiduels, qui sont susceptibles de jouer un rôle dans la spermiogénèse. Grâce aux annotations de le Gene Ontology, j’ai pu établir une liste de 8 protéines ayant un rôle supposé dans la transduction du signal, la reconnaissance cellulaire ou bien la différenciation. Par ailleurs, j’ai pu établir par protéomique Shotgun un premier protéome des cellules de Sertoli, des cellules germinales et des corps résiduels chez le rat.
https://tel.archives-ouvertes.fr/tel-01127389

Droits : info:eu-repo/semantics/OpenAccess
NNT : 2014REN1S064
tel-01127389
https://tel.archives-ouvertes.fr/tel-01127389
https://tel.archives-ouvertes.fr/tel-01127389/document
https://tel.archives-ouvertes.fr/tel-01127389/file/2014REN1S064.pdf

Éditeur(s) : HAL CCSD Mineralogical Society of America
Résumé : International audience
Accessory phases are important hosts of trace elements; allanite may contain >90% of the REE in a bulk rock. The mobility and redistribution of several trace elements, notably HREE, Th, U, and Y is thus controlled by reactions involving allanite and other REE phases, as well as several rock-forming minerals. As these elements are commonly concentrated in mature elastic sediments, a suite of impure quartzite was studied. Two eclogite facies samples from the Monometamorphic Cover Complex of the Sesia Zone (Western Italian Alps) are presented in some detail, as they reveal a remarkably rich spectrum of reaction relationships that involve REE phases.;Two allanite-forming reactions were inferred from textures and phase compositions;(1) monazite + Ca-silicate(?) + fluid -> allanite + apatite + thorite;;(2) monazite + thorite + Ca-silicate(?) + fluid -> Th-rich allanite + auerlite +/- apatite.;Petrographic observations and thermodynamic models suggest that allanite entered the HP assemblage at similar to 530 degrees C and 17-18 kbar during prograde metamorphism.;In one sample, allanite is rimmed by epidote rich in Y and HREE that grew at the expense of xenotime. Two net transfer reactions were derived;(3) xenotime + allanite + fluid -> Y-rich epidote + apatite + thorite;;(4) xenotime + allanite + fluid -> Y-rich epidote + aeschynite + thorite + (phosphate?).;Textural relationships and trace element analyses of coexisting allanite/monazite and xenotime/Y-rich epidote reveal systematic partitioning of the REE. Partition coefficients for the HREE are compatible with equilibrium fractionation, whereas those for the LREE show patterns that seem to be inherited from the precursor phases, in this case zircon with variable LREE composition.
ISSN: 0003-004X

hal-00745674
https://hal.archives-ouvertes.fr/hal-00745674
DOI : 10.2138/am.2012.3832

Éditeur(s) : HAL CCSD BioMed Central
Résumé : International audience
Background: End-Stage renal disease (ESRD) causes considerable morbidity and mortality, and significantly alterspatients’ quality of life. There are very few published data on this problem in the French Overseas territories. Thedevelopment of a registry on end stage renal disease in French Guiana in 2011 allowed to describe the magnitudeof this problem in the region for the first time.Methods: Using data from the French Renal Epidemiology and Information Network registry (R.E.I.N). Descriptivestatistics on quantitative and qualitative variables in the registry were performed on prevalent cases and incidentcases in 2011, 2012 and 2013.Results: French Guiana has one of the highest ESRD prevalence and incidence in France. The two main causes ofESRD were hypertensive and diabetic nephropathies. The French Guianese population had a different demographicprofile (younger, more women, more migrants) than in mainland France. Most patients had at least one comorbidity,predominantly (95.3%) hypertension. In French Guiana dialysis was initiated in emergency for 71.3% of patients versus33% in France (p < 0.001).Conclusion: These first results give important public health information: i) End stage renal disease has a very highprevalence relative to mainland France ii) Patients have a different demographic profile and enter care late in thecourse of their renal disease. These data are closer to what is observed in the Caribbean or in Latin America than inMainland France.
ISSN: 1471-2369

inserm-01567222
http://www.hal.inserm.fr/inserm-01567222
http://www.hal.inserm.fr/inserm-01567222/document
http://www.hal.inserm.fr/inserm-01567222/file/2017%2C%20Rochemont%20-%20End%20stage%20renal%20disease.pdf
DOI : 10.1186/s12882-017-0614-6

Éditeur(s) : HAL CCSD American Geophysical Union
Résumé : International audience
We recover the Holocene earthquake history of seven seismogenic normal faults in the Fucino system, central Italy. We collected 800 samples from the well-preserved limestone scarps of the faults and modeled their 36Cl concentrations to derive their seismic exhumation history. We found that > 30 large earthquakes broke the faults in synchrony over the last 12 ka. The seven faults released strain at the same periods of time, 12-9 ka, 5-3 ka, and 1.5-1 ka. On all faults, the strain accumulation and release occurred in 3-6 ka supercycles, each included a 3-5 ka phase of slow (≤ 0.5-2 mm/yr) strain accumulation in relative quiescence, followed by a cluster of three to four large earthquakes or earthquake sequences that released most of the strain in < 1-2 ka. The large earthquakes repeated every 0.5 ± 0.3 ka during the paroxysmal phases and every 4.3 ± 0.9 ka between those phases. Earthquakes on the northern faults produced twice larger surface slips (~ 2 m) and had larger magnitudes (Mw 6.2-6.7) than those on the southern faults. On most faults, the relative strain level was found to control the amount of slip and the time of occurrence of the next large earthquake. Faults entered a phase of clustered activity once they had reached a specific relative strain threshold. The Tre Monti fault is identified as the most prone to break over the next century. Our data document earthquake synchrony and clustering at a broader space and time scale than has been reported to date.
ISSN: 0148-0227

hal-00903460
https://hal.archives-ouvertes.fr/hal-00903460
DOI : 10.1002/jgrb.50299

Éditeur(s) : Elsevier
Résumé : To improve the knowledge of the survival of enteric viruses in a marine environment, the influence of physico-chemical parameters (temperature, UV, salinity) on the survival of infectious poliovirus 1 and hepatitis A Virus (HAV) in seawater was first studied, the influence of suspended solids (SS) on poliovirus adsorption and survival in seawater was then evaluated and the detection of rotavirus genome in environmental samples (shellfish, river water, treated wastewater) was finally investigated. The results show that temperature has a major impact on virus survival in seawater as the time necessary to inactivate 90 % of the virus (T-90) is 671 days at 4 degrees C and only 25 days at 25 degrees C. Ultraviolet light (42 mW s cm(-2)) rapidly inactivates viruses but HAV is more resistant (T-90 = 2.6 min) than the poliovirus 1 (T-90 = 1.3 min). By contrast, seawater salinity has no effect on virus survival. In presence of SS, 90 % to 99.9 % of the viruses were adsorbed. This adsorption does not provide any protection for viruses with low SS concentrations (3 and 15 mg L-1) but a slight increase in virus survival was observed with a high SS concentration (500 mg L-1). Finally environmental sample analysis indicated that 20 % shellfish, about 40 % river water and 40 % treated wastewater tested positive for the rotavirus genome.
Ce travail a pour but de mieux comprendre le devenir des virus en milieu marin. Dans ce cadre, l'influence de certains paramètres physicochimiques (température, UV et salinité) sur le pouvoir infectieux du poliovirus 1 et du virus de l'hépatite A (VHA) en eau de mer a été évalué, puis l'adsorption du poliovirus 1 sur les matières en suspension (MES) a été étudié, ainsi que les conséquences sur le pouvoir infectieux du virus et enfin le génome des rotavirus a été recherché en milieu naturel (eaux et coquillages). Les résultats montrent que la température est un paramètre important pour la survie des virus puisque le temps nécessaire à inactiver 90 % des virus (T90) en eau de mer est de 671 j à 4 °C alors qu'il est seulement de 25 j à 25 °C. Le rayonnement ultraviolet (42 mW s cm−2) testé en pilote expérimental, permet d'obtenir une inactivation rapide du poliovirus 1 (T90 = 1,3 min). Le VHA est plus résistant avec un T90 = 2,6 min. En revanche la salinité de l'eau de mer n'a pas d'influence sur la survie des virus. En ce qui concerne l'influence des MES, les résultats montrent qu'en présence de 3, 15 et 500 mg L−1 de Na-montmorillonite la majorité des virus est adsorbée (90 à 99,9 %). Cet état adsorbé ne procure aucune protection aux virus pour les faibles concentrations de MES (3 et 15 mg L−1) alors qu'une augmentation significative de survie est observée pour les fortes concentrations (500 mg L−1). Enfin, l'analyse d'échantillon de l'environnement a montré que 20 % des fruits de mer, environ 40 % des eaux de rivière et environ 40 % des eaux usées traitées testées contenaient du génome de rotavirus.
Oceanologica Acta (0399-1784) (Elsevier), 1998-11 , Vol. 21 , N. 6 , P. 983-992

Droits : 1998 Ifremer / CNRS / IRD - Published by Elsevier SAS
http://archimer.ifremer.fr/doc/1998/publication-846.pdf
DOI:10.1016/S0399-1784(99)80020-6
http://archimer.ifremer.fr/doc/00000/846/

Éditeur(s) : HAL CCSD Springer-Verlag
Résumé : The Chile-Argentina Patagonian Cordillera is a natural laboratory to study the interactions between oceanic and continental lithosphere during the subduction of an active spreading ridge beneath a continent. Subduction of the South Chile spreading ridge, which separates the Nazca plate from the Antarctic plate, started around 15–14 Ma at the southern tip of Patagonia. Presently, the southernmost segment of the Chile Ridge enters the Peru-Chile trench at 46°S, at the site of the Chile Triple Junction (CTJ). We review the main events which occurred on land in the CTJ region (46–47°S), related with processes of ridge subduction. We summarize tectonic, sedimentary, and magmatic features in a 30 Ma-to Present chronological table. A preridge subduction stage, from 30 to 15 Ma, is characterized by the onset and growth of Patagonian relief and by a shift from marine to continental detrital sedimentation in the foreland at 20–22 Ma. The change from pre-ridge subduction to ridge subduction is marked on land by a transition from calc-alkaline to alkaline volcanism, at 14–12 Ma, and by the onset of eruption of very large fl ood basalt provinces (future volcanic plateaus) following rapid erosion of the eastern foreland belt. Post-plateau basaltic volcanism (<4 Ma) is coeval with a period of tectonic and morphological rejuvenation during which the eastern foreland of the Cordillera has been affected by extensional/transtensional tectonics. We place these events in the framework of a tectonomagmatic model involving the opening of slab windows due to both slab tear and ridge axis subduction.
Subduction Zone Geodynamics

hal-00421053
https://hal.archives-ouvertes.fr/hal-00421053
DOI : 10.1007/978-3-540-87974-9_12

Éditeur(s) : HAL CCSD
Résumé : International audience
Les plages sableuses constituent une frontière mobile et poreuse entre l'océan ouvert et la terre. La compréhension de la circulation dans les nappes de plage est importante pour une variété de processus physiques, biologiques et chimiques. On cherche à caractériser in-situ la dynamique souterraine sous la zone de swash. Le site atelier est la plage microtidale de Rousty (Camargue, France). L'étude, réalisée sur 48h les 13 et 14 décembre 2014, fait partie d'une plus grande campagne de mesure visant à caractériser la réponse hydro-morphologique de la plage de Rousty à une saison hivernale. La période présentée ici correspond à la phase de déclin d'une tempête modérée. La stratégie retenue dans le cadre de ce projet a été de déployer un réseau de15 capteurs de pression enterrés sous la zone de swash. Les caractéristiques des vagues incidentes, à la fois au large et dans la zone de surf interne, ont été mesurées conjointement à l'utilisation d'un LiDAR terrestre haute fréquence permettant de suivre la surface libre et l'évolution du lit sableux à haute fréquence sur la zone de swash. L'analyse des données moyennées dans le temps a mis en évidence la présence d'un schéma de circulation relativement robuste sous la zone de swash, qui se décale vers le large en suivant la descente du niveau moyen et la diminution de l'activité des vagues. La tendancedominante est un écoulement vers le large, avec une intensité maximale de l'ordre de 0.1mm/s modulé par des infiltrations et exfiltrations dans les parties hautes et basses de la zone de swash, respectivement. L'analyse haute fréquence à des événements de swash sélectionnés ont mis en évidence uncycle souterrain caractéristique.
XIV èmes Journées Nationales Génie Côtier – Génie Civil
toulon, France

hal-01357778
https://hal.archives-ouvertes.fr/hal-01357778

Résumé : Hierba bulbífera escamosa, bulbos divididos de hasta 10 cm de diámetro, tunicados. Hojas basales, de hasta 40 cm, huecas, semicirculares en sección transversal. Escapo de hasta 60 cm de altura. Abundantes flores moradas o casi blancas, agrupadas en una umbela grande, esférica, con 2 a 3 brácteas. Fruto capsular. Raras veces llega a producir semillas.
Herbe bulbeuse à écailles, bulbes divisés pouvant atteindre 10 cm de diamètre, tuniqués. Feuilles basales, pouvant atteindre 40 cm, creuses, semi-circulaires en section transversale. Hampe florale pouvant atteindre 60 cm de haut. Fleurs abondantes, violettes ou presque blanches, groupées en une grande ombelle sphérique, de 2 à 3 bractées. Fruit capsulaire. Produit rarement des graines.
Bulbous and scaly herb; bulbs up to 10 cm in diameter, tunicated.  Leaves basal, up to 40 cm in length, hollow, semi-circular or in cross-section.  Scape up to 60 long.  Flowers numerous, purple or almost white, grouped in large, spherical umbel, with 2 to 3 bracts.  Fruit capsular.
Oriunda de Asia occidental es extensamente cultivada en el mundo entero.
Originaire d&rsquo;Asie occidentale; sa culture est très répandue dans le monde entier.
Native to western Asia, widely cultivated around the world.

http://www.tramil.net/fototeca/plant408

Éditeur(s) : Scientific Technical Research Council Turkey-tubitak
Résumé : In 2002, the Bosphorus outlet was mapped using an EM 300 multibeam echo-sounder together with a Chirp sonar system. This survey, carried out on board the Ifremer RV 'Le Suroit' in the frame of the BlaSON project, completes the data previously acquired directly at the mouth of the Bosphorus by Di Iorio et al. (1999) in the frame of a NATO SACLANT Undersea Research project using jointly the NATO RV Alliance, and the Turkish Navy Survey ship 'Cubuklu'. This acoustic imaging has identified a canyon system at the slope and a shallow marine fan, which contains shelf incisions extending the Istanbul Strait incision. Multibeam bathymetry, ultra-high resolution seismic profiling and coring correlations on this subaqueous fan area allowed reconstruction of morphology and patterns of sediment distribution indicative of high energy sediment transport processes. The discovery of a shallow water/shelf type fan directly off shore from the Bosphorus and connected to its outlet is consistent with the theories of sudden discharges of large volumes of water. Age dating obtained at the bottom of this subaqueous shelf fan yielded an age of 6700 yr C-14 BP (uncorrected age) for the first marine mollusc encountered at the base. This is in accordance with a last and abrupt reconnection of the Marmara Sea to the Black Sea. A detailed morphological map of the shelf and slope along with seismic profile interpretation and core correlation is presented here. A synthesis is proposed to explain the formation of this subaqueous fan and its relationship with the last connection between Black and Marmara seas aft er the Last Glacial Maximum. This interpretation can be summarized as follows: stage A corresponds to the first erosion surface seen on the shelf related to the Last Glacial Maximum low stand; stage B is the ravine surface onlapping to ca. -30, -40 m; stage C is a second erosional surface related to a sea level fall and eroding most of underlying Unit 1B; and stage D corresponds to the onset of the fan deposit during a period of high water run-off from the Black Sea entering from the Bosphorus. Avulsion branches show that this fan has been active for a long time.
Turkish Journal Of Earth Sciences (1300-0985) (Scientific Technical Research Council Turkey-tubitak), 2011 , Vol. 20 , N. 3 , P. 287-305

Droits : 2011 TÜBİTAK
http://archimer.ifremer.fr/doc/00036/14676/13677.pdf
http://archimer.ifremer.fr/doc/00036/14676/

Éditeur(s) : Elsevier Science Bv
Résumé : Coastal and estuarine systems provide nursery grounds for many marine fish species. Their productivity has been correlated with terrigeneous inputs entering the coastal-estuarine benthic food web, thereby favouring the establishment of fish juveniles. Studies in these ecosystems often describe the nursery as a single large habitat without verifying nor considering the presence of contiguous habitats. Our study aimed at identifying different habitats based on macrozoobenthic communities and morpho-sedimentary characteristics and assessing the trophic interactions between fish juveniles and their benthic preys within these habitats. It included 43 sampling sites covering 5 habitats in which we described taxonomically and quantitatively the invertebrates and fish communities with stable isotopes and gut contents. It suggested that the benthic common sole Solea solea displayed feeding plasticity at the population level, separating the juveniles (G0) from the older fish (G1) into different "feeding sub-populations". Size-based feeding plasticity was also observable in the spatial occupancy of that species in the studied bay. The demersal pouting, Trisopterus luscus, equally used the different habitats but displayed low feeding plasticity across and inside each habitat. Stable isotopes proved to be powerful tools to study the spatial distribution of trophic interactions in complex ecosystems like the bay of Vilaine and to define optimal habitats for fish that use the coastal-estuarine ecosystem as nursery grounds.
Journal Of Sea Research (1385-1101) (Elsevier Science Bv), 2013-08 , Vol. 81 , P. 40-48

Droits : 2013 Elsevier B.V. All rights reserved
http://archimer.ifremer.fr/doc/00151/26226/24327.pdf
DOI:10.1016/j.seares.2013.03.013
http://archimer.ifremer.fr/doc/00151/26226/

Éditeur(s) : Université des Antilles Études caribéennes
Résumé : Sur la terre ferme, la sécurité est devenue un thème récurrent de la vie politique, des imaginaires voire de la réalité. Dans le monde de la croisière au contraire, la communication vend un univers idyllique. Or la réalité de la vie à bord du navire n’est pas faite que de bonheur, et les armateurs, les voyagistes, les équipages et les autorités administratives anticipent des situations qui mettent en péril les passagers. La gestion des épidémies ne se limite pas à la grippe H1N1, moment exceptionnel qui cache la réalité fréquente des épidémies de gastro-entérite. Le quotidien sécuritaire est aussi constitué par les risques plus traditionnels : le feu et le naufrage. La croisière également s’accompagne de viols et violences sur des croisiéristes, voire de disparitions de passagers. Ces trois dangers de la croisière font l’objet de mesures de santé publique, de définition de normes de sécurité internationales depuis 1914, et de mesures législatives récentes, puisque le dernier texte a été promulgué par le président Obama en juillet 2010. L’Europe montre un retard important dans l’organisation de cette politique, gage de développement de l’industrie de la croisière.
On land, security has become a recurring theme in the political life of the imagination or reality. In the world of cruising the contrary, communication sells idyllic world. The reality of life on the ship is not made that happiness, and shipowners, operators, crews and administrative authorities anticipate situations that endanger passengers. Outbreak management is not limited to the H1N1 exceptional moment that hides the reality of frequent outbreaks of gastroenteritis. The daily safe is also constituted by the more traditional risks: fire and sinking. The cruise also accompanied by rape and violence on cruise or disappearances of passengers. These three dangers of the cruise are the subject of public health measures, definition of international safety standards since 1914, and recent legislation, since the final text was issued by President Obama in July 2010. Europe shows a significant delay in the organization of the political guarantee for the development of the cruise industry.

Droits : info:eu-repo/semantics/openAccess
urn:doi:10.4000/etudescaribeennes.5220
http://journals.openedition.org/etudescaribeennes/5220

Éditeur(s) : Wiley-blackwell Publishing, Inc
Résumé : Oceanic larvae of the European (Anguilla anguilla) and American (A. rostrata) eels have to cross the Atlantic Ocean from the Sargasso Sea to European or North American coasts before entering continental habitats. In some European rivers, eel recruitment is now < 1% of levels in the 1980s. A better understanding of the effects of anthropogenic pressures and environmental fluctuations on eel larvae and subsequent recruitment is a prerequisite to build efficient management plans. The present paper provides insight into the critical oceanic phase of the eel life cycle with a focus on the duration of the larval migration whose estimates varies between 7 months and more than 2 years in both species. Does this range correspond to a natural variability in larval duration or does it stem from methodological artefacts? We first review the different methods used to estimate the duration of larval migration and critically describe their possible sources of misinterpretation. We then evaluate the consistency of these methods with the current knowledge about the ecology and physiology of eel larvae and the physical oceanography. While a moderate discrepancy in migration duration was found between methods for the American eel, the discrepancy was large in the European eel. In this species, otolith microstructure studies indicated migration durations between 7 and 9 months, while other methods pointed to durations of about 2 years. We show that estimates in favour of a long migration duration seem more robust to methodological caveats than methods estimating short durations of migration.
Fish And Fisheries (1467-2960) (Wiley-blackwell Publishing, Inc), 2010-09 , Vol. 11 , N. 3 , P. 289-306

Droits : 2010 Blackwell Publishing Ltd.
http://archimer.ifremer.fr/doc/00011/12208/9033.pdf
DOI:10.1111/j.1467-2979.2010.00362.x
http://archimer.ifremer.fr/doc/00011/12208/

Éditeur(s) : HAL CCSD Oxford University Press (OUP)
Résumé : International audience
Convergent plate margins typically experience a transition from subduction to collision dynamics as massive continental blocks enter the subduction channel. Studies of high-pressure rocks indicate that tectonic fragments are rapidly exhumed from eclogite facies to mid-crustal levels, but the details of such dynamics are controversial. To understand the dynamics of a subduction channel we report the results of a petrochronological study from the central Sesia Zone, a key element of the internal Western Alps. This comprises two polymetamorphic basement complexes (Eclogitic Micaschist Complex and Gneiss Minuti Complex) and a thin, dismembered cover sequence (Scalaro Unit) associated with pre-Alpine metagabbros and metasediments (Bonze Unit). Structurally controlled samples from three of these units (Eclogitic Micaschist Complex and Scalaro-Bonze Units) yield unequivocal petrological and geochronological evidence of two distinct high-pressure stages. Ages (U-Th-Pb) of growth zones in accessory allanite and zircon, combined with inclusion and textural relationships, can be tied to the multi-stage evolution of single samples. Two independent tectono-metamorphic 'slices' showing a coherent metamorphic evolution during a given time interval have been recognized: the Fondo slice (which includes Scalaro and Bonze rocks) and the Druer slice (belonging to the Eclogitic Micaschist Complex). The new data indicate separate stages of deformation at eclogite-facies conditions for each recognized independent kilometer-sized tectono-metamorphic slice, between ∼85 and 60 Ma, with evidence of intermittent decompression (ΔP ∼ 0*5 GPa) within only the Fondo slice. The evolution path of the Druer slice indicates a different P-T-time evolution with prolonged eclogite-facies metamorphism between ∼85 and 75 Ma. Our approach, combining structural, petrological and geochronological techniques, yields field-based constraints on the duration and rates of dynamics within a subduction channel.
ISSN: 0022-3530

hal-01054335
https://hal.archives-ouvertes.fr/hal-01054335
DOI : 10.1093/petrology/egu029

Éditeur(s) : HAL CCSD Oxford University Press
Résumé : International audience
It was recently reported that the sizes of many mRNAs change when budding yeast cells exit mitosis and enter the meiotic differentiation pathway. These differences were attributed to length variations of their untranslated regions. The function of UTRs in protein translation is well established. However, the mechanism controlling the expression of distinct transcript isoforms during mitotic growth and meiotic development is unknown. In this study, we order developmentally regulated transcript isoforms according to their expression at specific stages during meiosis and gametogenesis, as compared to vegetative growth and starvation. We employ regulatory motif prediction, in vivo protein-DNA binding assays, genetic analyses and monitoring of epigenetic amino acid modification patterns to identify a novel role for Rpd3 and Ume6, two components of a histone deacetylase complex already known to repress early meiosis-specific genes in dividing cells, in mitotic repression of meiosis-specific transcript isoforms. Our findings classify developmental stage-specific early, middle and late meiotic transcript isoforms, and they point to a novel HDAC-dependent control mechanism for flexible transcript architecture during cell growth and differentiation. Since Rpd3 is highly conserved and ubiquitously expressed in many tissues, our results are likely relevant for development and disease in higher eukaryotes.
ISSN: 0305-1048

Droits : http://creativecommons.org/licenses/by/
hal-01122128
https://hal-univ-rennes1.archives-ouvertes.fr/hal-01122128
https://hal-univ-rennes1.archives-ouvertes.fr/hal-01122128/document
https://hal-univ-rennes1.archives-ouvertes.fr/hal-01122128/file/The%20conserved%20histone%20deacetylase.pdf
DOI : 10.1093/nar/gku1185

Éditeur(s) : HAL CCSD Wiley-Blackwell
Résumé : International audience
AIMS: Virus detection has often been difficult due to a low concentration in water. In this study, we developed a new procedure based on concentration of virus particles on an innovative support: poly-L-lysine dendrigrafts (DGL), coupled with directed nucleic acid extraction and real-time PCR quantification. METHODS AND RESULTS: This method was evaluated using the bacteriophage MS2 as a model virus. This virus exhibited the size and structural properties of human pathogenic enteric viruses and has often been used to assess new supports of concentration. Moreover, this bacteriophage is also a faecal contamination indicator. In this study, many water filtration conditions were tested (volume of water, concentration, etc.), and more than 80% of bacteriophage were recovered after filtration on polymer, in most conditions. We demonstrated that the method was linear (slope = 0*99 ± 0*04 and Y intercept when x = -0*02 ± 0*28), valid (as manipulators, tested concentrations, volumes of sample and batch of polymer did not have any influence on concentration) and sensitive (allowing to concentrate up to 16,600-fold 1 l of sample and to detect and quantify down to 750 GC l(-1) and 7500 GC l(-1), respectively). CONCLUSIONS: To conclude, this support exhibits high interest to retain viruses and to allow to detect low concentration of virus in water. SIGNIFICANCE AND IMPACT OF THE STUDY: This study gives valuable advance in the methods of concentration and diagnosis of virus in water.
Journal of Applied Microbiology

hal-00828987
https://hal.archives-ouvertes.fr/hal-00828987
DOI : 10.1111/jam.12209
PUBMED : 23551794

Éditeur(s) : HAL CCSD Elsevier
Résumé : International audience
Orogenic lherzolites exhibit a specific (although reproducible) platinum-group element signature characterized by slight positive deviations of Pd/Ir, Rh/Ir and Ru/Ir ratios from the canonical chondritic model. Such a signature was alternatively considered to be a compositional feature of the primitive upper mantle or resulting from sulfide melt addition by refertilisation reactions in the continental lithosphere. To shed additional light on this conundrum, the distribution of PGE in FON B 93, an unserpentinized, fertile (3.24% Al2O3) orogenic lherzolite (French Pyrenees) used as in-house standard by our group, has been studied to different scales, from the bulk rock to trace minerals. In addition to new ICPMS analyses after separation into Nis and Te coprecipitation, its whole-rock PGE concentrations were redetermined by three different laboratories using very precise ID-ICP-MS methods after digestion of the sample in Carius tube at T=250 degrees C and 320 degrees C or in high-pressure asher (HPA-S). The four methods produce reproducible Ru, Rh and Pd contents (7.1 +/- 0.18 ppb; 1.43 +/- 0.05 ppb; 7.1 +/- 0.30 ppb) whereas the non-ID NiS-fire assay method underestimates the Os and Ir concentrations by c.a. 10 and 15% compared to ID-ICP-MS analyses (4.40 +/- 0.07 and 4.00 +/- 0.17 ppb, respectively). Platinum was the most difficult to analyse. If performed on powder aliquots smaller than 3 g, the ID-ICP-MS analyses generate strong nugget effects while the non-ID NiS-fire assay method yields statistically lower (but highly reproducible) Pt concentrations (6.92 +/- 0.26 ppb). These features reflect the strong partitioning of Pt into trace phases that SEM and laser ablation-ICP-MS analyses on thin sections identify as both high-temperature Pt-Ir-Os alloys and Pt-(Pd) tellurides of likely subsolidus origin; ten to fifteen grains ranging in maximum dimension from a few micrometres to a few hundreds of nanometers, were identified by standard polished thin section. LA-ICP-MS data on base metal sulfides (25 grains analysed), coupled with the whole-rock S concentration (277 +/- 10 ppm) and modal composition of the BMS (90% pentlandite+accessory pyrite and secondary pyrrhotite + 10% chalcopyrite) allowed the contribution of the BMS phase to the PGE budget of FON B 93 to be estimated. Except Pt that exhibits a 95% deficit in the BMS phase, the PGE concentrations measured by ID-ICP-MS can be balanced by BMS while Al-spinel is a negligible contributor, accounting for less than 0.5% of the Ru budget. The occurrence of Pt in trace phases may bias the whole-rock Pt concentrations because 1) mechanical collection of Pt-rich trace phases remains problematic with the Nis button, and 2) Pt-Ir-Os alloys may be prone to digestion problems in conventional Carius tube procedures. Since they could be stable at mantle depth, such refractory alloys that contain Os and Ir may also have enhanced the heavy PGEs/light PGEs fractionation. Our observations likely pertain to orogenic lherzolites as a whole because BMS assemblages in these mantle rocks record evolution at low sulfur fugacity, which prevents Pt-Ir-Os alloy from entering the Mss in the mantle; moreover, at subsolidus temperature, pentlandite, the major BMS, cannot accommodate 0 valence state Pt.
ISSN: 0009-2541

hal-00411486
https://hal.archives-ouvertes.fr/hal-00411486
DOI : 10.1016/j.chemgeo.2007.06.030

Éditeur(s) : HAL CCSD American Association for the Advancement of Science
Résumé : International audience
Sediments cored along the southwestern Iberian margin during Integrated Ocean Drilling Program Expedition 339 provide constraints on Mediterranean Outflow Water (MOW) circulation patterns from the Pliocene epoch to the present day. After the Strait of Gibraltar opened (5.33 million years ago), a limited volume of MOW entered the Atlantic. Depositional hiatuses indicate erosion by bottom currents related to higher volumes of MOW circulating into the North Atlantic, beginning in the late Pliocene. The hiatuses coincide with regional tectonic events and changes in global thermohaline circulation (THC). This suggests that MOW influenced Atlantic Meridional Overturning Circulation (AMOC), THC, and climatic shifts by contributing a component of warm, saline water to northern latitudes while in turn being influenced by plate tectonics.
ISSN: 0036-8075

hal-01054316
https://hal.archives-ouvertes.fr/hal-01054316
DOI : 10.1126/science.1251306