![]() | Volcano tourism in St. Lucia and Dominica: Combining Science and Community Auteur(s) : Joseph, Erouscilla Année de publication : Loading the player... Éditeur(s) : Université des Antilles AREBio Groupe de recherche BIOSPHERES : BIOlogie, Sciences Physiques & Humaines pour les énergies Renouvelables, l Extrait de : 1er colloque international BIOSPHERES, du 18 au 20 juin 2019. Université des Antilles Description : Volcano tourism plays an important role in the economies of volcanic islands in the Lesser Antilles. On islands like St. Lucia and Dominica these volcanoes have been utilized as geoparks and the areas even being designated as World Heritage Sites. In many of these islands, farming communities also live on the slopes to these volcanoes and with the increased pursuit of geothermal energy the siting of geothermal operations are also located in close proximity. Volcanic activity, therefore, has a significant impact on these islands at a local and national level. Many volcanomonitoring institutions face the financial and human resources challenge of providing ongoing monitoring services to economically burdened small island states. This has often led to the exploration of alternative low-cost monitoring options and strategies to be adopted by monitoring agencies. One such strategy is the adoption of a volcanic risk reduction approach to research and monitoring activities, which integrates the social and physical sciences through the engagement of local communities as partners with scientists in disaster risk reduction. We present a recent approach adopted using this type of strategy in St. Lucia and lessons learnt from this approach with implications for volcano tourism on island. The potential use of this strategy in Dominica is also presented, given the economic challenges the island currently faces during its ongoing recovery efforts from Hurricane Maria in 2017. Droits : CC-BY-NC-ND - Attribution - Pas d'utilisation commerciale - Pas de modification Permalien : http://www.manioc.org/fichiers/V19086 V19086 | Partager |
![]() | Characterization of potentially avoidable cases in a 1-year series of consecutive cesarean sections in the tertiary maternity unit of Guadeloupe (French West Indies) Auteur(s) : Kadhel, Philippe Delrieu, Delphine Deloumeaux, Jacqueline Ryan, Catherine Janky, Eustase Auteurs secondaires : Institut de recherche, santé, environnement et travail [Rennes] (Irset) ; Université d'Angers (UA) - Université des Antilles et de la Guyane (UAG) - Université de Rennes 1 (UR1) - École des Hautes Études en Santé Publique [EHESP] (EHESP) - Institut National de la Santé et de la Recherche Médicale (INSERM) - Structure Fédérative de Recherche en Biologie et Santé de Rennes ( Biosit : Biologie - Santé - Innovation Technologique ) Service de gynécologie-obstétrique ; Université des Antilles et de la Guyane (UAG) - CHU Pointe à Pitre Université des Antilles et de la Guyane (UAG) Éditeur(s) : HAL CCSD Résumé : International audience Aim The global increase in the rate of cesarean sections (CS) is currently an issue. We aimed to assess the rate of CS locally and to identify cases in which this procedure may have been avoidable. Methods In this prospective consecutive series, we analyzed the 478 CS carried out in our unit in 2009. We analyzed the characteristics of each case, and classified each as potentially avoidable or unavoidable. Results The total rate of CS was 24.0%, including 1.7% that was scored as potentially avoidable. Parity, gestational age at birth, birthweight, cases requiring cervical ripening, cases of labor induction, and CS during labor were all significantly higher or more frequent among potentially avoidable CS. Multivariate analysis indicated that the risk of potentially avoidable CS was positively associated with gestational age and tended to be negatively associated with parity. The main indications for potentially avoidable CS were cervical dystocia and abnormal fetal heart rate, and for unavoidable CS they were abnormal fetal heart rate and history of previous CS. Conclusion Labor, especially when induced, seems to be the key period for the prevention of ‘avoidable’ CS. This is particularly important given that potentially avoidable CS are more frequently associated with uncomplicated pregnancies than are unavoidable CS. A woman's first CS increases the likelihood of CS for subsequent deliveries, so the prevention of the first CS is a key aim for reducing the overall rate of CS Journal of Obstetrics and Gynaecology Research hal-01305484 https://hal-univ-rennes1.archives-ouvertes.fr/hal-01305484 PUBMED : 27094021 DOI : 10.1111/jog.13007 | Partager |
![]() | Mulching effects of fresh Sargassum Seaweed on soil properties and plant growth ; Effets des Sargasses Seaweed sur les propriétés du sol et la croissance des plantes. Auteur(s) : Lopez, Francis Année de publication : Loading the player... Éditeur(s) : Université des Antilles. Service commun de la documentation University of West Indies, Barbados Extrait de : 52e congrès annuel de la Société caribéenne des plantes alimentaires / 52nd annual meeting of the Caribbean food crops society (CFCS), du 10 au 16 juillet 2016. INRA, CFCS Description : Mulch application of Sargassum seaweed (Sargassum spp.) to soil can help to reduce beach contamination in the Caribbean Region while providing beneficial horticultural effects. This study investigated the effects of fresh Sargassum mulch on soil properties and plant growth in a test crop of tomato (Solanum lycopersicum L. â? ? HA 3019â? TM). Fresh Sargassum material (washed and unwashed) was applied as mulches (0, 5 and 8cm thick) to small field plots one week after transplanting of 3-week-old seedlings. The mulch material was raked away from the plots after three weeks exposure. Observations on soil moisture, electrical conductivity, pH and biological activity, and plant growth were made at 1 to 2-week intervals over a 6-week period with additional soil measurements after 10 weeks. Soil biological activity (respiration) was increased by the Sargassum mulch with values being similar for the 5cm and 8cm mulch layers. Soil moisture content, pH and electrical conductivity (EC) were increased as the mulch layer increased and EC values were only marginally reduced by Sargassum washing. An increase in plant growth compared to the control treatment was noted only in the washed Sargassum treatments. Potential benefits of Sargassum seaweed mulches on soil properties and plant growth can be nullified due to soil salinization effects. Siècle(s) traité(s) : 21 Droits : CC-BY-NC-ND - Attribution - Pas d'utilisation commerciale - Pas de modification Permalien : http://www.manioc.org/fichiers/V16269 V16269 | Partager |
![]() | Effect of an herbivorous diet on energy balance of Litopenaeus vannamei at selected ontogenetic stages Auteur(s) : Maldonado, Carlos Cuzon, Gerard Guzman, Emilio Brito, Roberto Soto, Luis Arena, Leticia Gaxiola, Gabriela Éditeur(s) : Elsevier Résumé : Herbivorous (20% vegetable protein, 40% carbohydrate) and carnivorous diets (40% marine animal protein, 20% carbohydrate) were experimentally tested to assess their effect on the energy balance and energetic substrates utilized by postlarvae (PL's /15 days) and juvenile shrimp (3-6 g) of Litopenaeus vannamei. Postlarval stage 60 (PL60, early juveniles) shrimps fed HeD and CaD diets, then late juveniles (3-6 g) acclimated to the same diets were tested for their respective energy partitioning potential. No significant differences (p>0.05) on growth were obtained in early juveniles (mean final wet weight of 0.19 g). However in late juvenile stages a significant difference (p<0.05) in growth rate was observed. In terms of energy partitioning, both early and late juveniles seem to spend more energy in respiratory metabolism than in the elimination of excretion products. A change in feed composition based on quality protein sources induced some modifications on shrimp's activity measured by heat increment. Shrimps fed with an herbivorous diet showed a higher heat increment. Interestingly, the early stages of L vannamei display a remarkable capacity to assimilate a plant protein-based and a high carbohydrate level diet. Such capacity with a stimulation of genes would lead to a good adaptation of juveniles receiving all-plant diets to sustain growth performances up to a marketable size. The implications of these findings for the shrimp farming feeding costs are briefly discussed. (C) 2009 Elsevier B.V. All rights reserved. Aquaculture (0044-8486) (Elsevier), 2009-11 , Vol. 296 , N. 1-2 , P. 123-128 Droits : 2009 Elsevier B.V. All rights reserved. http://archimer.ifremer.fr/doc/2009/publication-7402.pdf DOI:10.1016/j.aquaculture.2009.08.007 http://archimer.ifremer.fr/doc/00000/7402/ | Partager |
![]() | Potential for use of Sargasum Mulch in Swee Potato production ; Potentiel d'utilisation de Sargasse dans la production de patate douce Auteur(s) : Veira, Andréa K. Année de publication : Loading the player... Éditeur(s) : University of West Indies, Barbados Université des Antilles. Service commun de la documentation Extrait de : 52e congrès annuel de la Société caribéenne des plantes alimentaires / 52nd annual meeting of the Caribbean food crops society (CFCS), du 10 au 16 juillet 2016. INRA, CFCS Description : Practical uses for Sargassum are sought regionally as our coastlines continue to be flooded by sargassum blooms floating ashore. This study investigated the potential benefits of Sargassum (Sargassum spp.) mulch in sweet potato production at Golden Ridge, St. George, Barbados, during a drought period (November 2015-March 2016). Treatment consisted of combinations of two cultivars of sweet potato (?E? and ?CBS 32?, main-plots) and washed/unwashed Sargassum mulches (sub-plots) of different ages (approximately 4 weeks old and fresh, sub-sub-plots) with four replications. Sargassum mulch was applied to the furrows of plots (6m2) four weeks after planting at a rate of 10 t ha-1 and yield, growth and soil parameters were monitored at periodic intervals. Yield (t ha-1) was highest for the 4-weeks old Sargassum mulch treatment, and the number of marketable tubers was highest for the unwashed 4-weeks old Sargassum treatment. The number of tubers with Euscepes postfaciatus (Scarabee) pest damage was decreased by the Sargassum mulch treatments especially for the 4-weeks old unwashed Sargassum. Vine growth was taller for cultivar ?E? and for the washed Sargassum treatments. Chlorophyll indices were higher in ?CBS 32? than in cultivar ?E? and were lower in Sargassum treated plots. Moisture content in the top 10cm of soil was consistently low and greater in plots of cultivar ?E? than in those of ?CBS 32?. There appears to be some potential for the use of aged Sargassum mulches for improving growth, pest management and yields of sweet potato and further investigations are needed. Siècle(s) traité(s) : 21 Droits : CC-BY-NC-ND - Attribution - Pas d'utilisation commerciale - Pas de modification Permalien : http://www.manioc.org/fichiers/V16270 V16270 | Partager |
![]() | Glyceollins trigger anti-proliferative effects through estradiol-dependent and independent pathways in breast cancer cells Auteur(s) : Lecomte, Sylvain Chalmel, Frédéric Ferrière, François Percevault, Frédéric Plu, Nicolas Saligaut, Christian Surel, Claire Lelong, Marie Auteurs secondaires : Institut de recherche, santé, environnement et travail [Rennes] (Irset) ; Université d'Angers (UA) - Université des Antilles et de la Guyane (UAG) - Université de Rennes 1 (UR1) - École des Hautes Études en Santé Publique [EHESP] (EHESP) - Institut National de la Santé et de la Recherche Médicale (INSERM) - Structure Fédérative de Recherche en Biologie et Santé de Rennes ( Biosit : Biologie - Santé - Innovation Technologique ) Analyses et Recherche ; Nutrinov This work was funded by FUI mVolio, Région Bretagne and Rennes Métropole. Éditeur(s) : HAL CCSD BioMed Central Résumé : International audience BACKGROUND: Estrogen receptors (ER) α and β are found in both women and men in many tissues, where they have different functions, including having roles in cell proliferation and differentiation of the reproductive tract. In addition to estradiol (E2), a natural hormone, numerous compounds are able to bind ERs and modulate their activities. Among these compounds, phytoestrogens such as isoflavones, which are found in plants, are promising therapeutics for several pathologies. Glyceollins are second metabolites of isoflavones that are mainly produced in soybean in response to an elicitor. They have potentially therapeutic actions in breast cancer by reducing the proliferation of cancer cells. However, the molecular mechanisms driving these effects remain elusive. METHODS: First, to determine the proliferative or anti-proliferative effects of glyceollins, in vivo and in vitro approaches were used. The length of epithelial duct in mammary gland as well as uterotrophy after treatment by E2 and glyceollins and their effect on proliferation of different breast cell line were assessed. Secondly, the ability of glyceollin to activate ER was assessed by luciferase assay. Finally, to unravel molecular mechanisms involved by glyceollins, transcriptomic analysis was performed on MCF-7 breast cancer cells. RESULTS: In this study, we show that synthetic versions of glyceollin I and II exert anti-proliferative effects in vivo in mouse mammary glands and in vitro in different ER-positive and ER-negative breast cell lines. Using transcriptomic analysis, we produce for the first time an integrated view of gene regulation in response to glyceollins and reveal that these phytochemicals act through at least two major pathways. One pathway involving FOXM1 and ERα is directly linked to proliferation. The other involves the HIF family and reveals that stress is a potential factor in the anti-proliferative effects of glyceollins due to its role in increasing the expression of REDD1, an mTORC1 inhibitor. CONCLUSION: Overall, our study clearly shows that glyceollins exert anti-proliferative effects by reducing the expression of genes encoding cell cycle and mitosis-associated factors and biomarkers overexpressed in cancers and by increasing the expression of growth arrest-related genes. These results reinforce the therapeutic potential of glyceollins for breast cancer. ISSN: 1478-811X hal-01560288 https://hal-univ-rennes1.archives-ouvertes.fr/hal-01560288 DOI : 10.1186/s12964-017-0182-1 PUBMED : 28666461 | Partager |
![]() | Microbial hydrogen production potential in shallow oceanic nepheloid layers. Auteur(s) : Schwarz, J Loeblich, L Schropp, S Éditeur(s) : Actes de colloques. Ifremer Brest [ACTES COLLOQ. IFREMER.]. 1986 Résumé : Seawater samples taken from shallow suspended particle maxima (20-57m) at or near the base of the surface mixed layer in various oceanic areas were tested for their potential to produce hydrogen (H sub(2)) gas. Results suggest that hydrogen can be bacterially produced through a fermentative process in microanaerobic niches within particulate matter. The organisms responsible for this process are ubiquitous within the temperate and tropical waters sampled. Enumeration of potential H sub(2)-producing bacteria using fluorescent antibody techniques yielded a maximum at the base of the surface mixed layer, the same depth where the greatest H sub(2) gas production potential was observed. Hydrogen-producing bacteria comprised up to 15% of the total bacterial direct count (AODC). Findings indicate that bacteria associated with shallow nepheloid layers are capable of producing gas and thus contributing to the observed supersaturated gas concentration in the marine environment. Des échantillons d'eau de mer contenant des particules en suspension ont été prélevés en zone peu profonde (20 à 57 m) sur ou près de la couche brassée de surface en différents points de l'océan et ont été testés pour leur potentiel de production d'H2. Les résultats suggèrent que l'hydrogène peut être produit, par les bactéries, lors d'un processus fermentatif dans des microniches anaérobies de la matière particulaire. Les organismes responsables de ce processus sont ubiquistes dans les échantillons provenant des eaux tempérées el tropicales. Les numérations maximales de bactéries potentiellement productrices d'hydrocele, faites par des techniques d'anticorps fluorescents, sont obtenues à la base de la couche brassée de surface ; à cette même profondeur est observé le potentiel de production d'hydrogène le plus important. Les bactéries productrices d'hydrogène constituent jusqu'à 15 % des numérations bactériennes totales, effectuées par comptage direct (AODC). Ces observations indiquent que les bactéries associées aux couches nephéloïdes peu profondes sont capables de produire de l'hydrogène et contribuent ainsi à la sursaturation en gaz observée dans le milieu marin. Droits : info:eu-repo/semantics/openAccess http://archimer.ifremer.fr/doc/1984/acte-962.pdf http://archimer.ifremer.fr/doc/00000/962/ | Partager |
![]() | Phylogenetic and Functional Diversity of Microbial Communities Associated with Subsurface Sediments of the Sonora Margin, Guaymas Basin Auteur(s) : Vigneron, Adrien Cruaud, Perrine Roussel, Erwan Pignet, Patricia Caprais, Jean-claude Callac, Nolwenn Ciobanu, Maria Cristina Godfroy, Anne Éditeur(s) : Public Library Science Résumé : Subsurface sediments of the Sonora Margin (Guaymas Basin), located in proximity of active cold seep sites were explored. The taxonomic and functional diversity of bacterial and archaeal communities were investigated from 1 to 10 meters below the seafloor. Microbial community structure and abundance and distribution of dominant populations were assessed using complementary molecular approaches (Ribosomal Intergenic Spacer Analysis, 16S rRNA libraries and quantitative PCR with an extensive primers set) and correlated to comprehensive geochemical data. Moreover the metabolic potentials and functional traits of the microbial community were also identified using the GeoChip functional gene microarray and metabolic rates. The active microbial community structure in the Sonora Margin sediments was related to deep subsurface ecosystems (Marine Benthic Groups B and D, Miscellaneous Crenarchaeotal Group, Chloroflexi and Candidate divisions) and remained relatively similar throughout the sediment section, despite defined biogeochemical gradients. However, relative abundances of bacterial and archaeal dominant lineages were significantly correlated with organic carbon quantity and origin. Consistently, metabolic pathways for the degradation and assimilation of this organic carbon as well as genetic potentials for the transformation of detrital organic matters, hydrocarbons and recalcitrant substrates were detected, suggesting that chemoorganotrophic microorganisms may dominate the microbial community of the Sonora Margin subsurface sediments. Plos One (1932-6203) (Public Library Science), 2014-08 , Vol. 9 , N. 8 , P. e104427 Droits : This is an open-access article, free of all copyright, and may be freely reproduced, distributed, transmitted, modified, built upon, or otherwise used by anyone for any lawful purpose. The work is made available under the Creative Commons CC0 public domain dedication. http://archimer.ifremer.fr/doc/00203/31408/29801.pdf DOI:10.1371/journal.pone.0104427 http://archimer.ifremer.fr/doc/00203/31408/ | Partager |
![]() | Potential Effect of Freshwater Virus on the Structure and Activity of Bacterial Communities in the Marennes-Oléron Bay (France) Auteur(s) : Auguet, Jean-christophe Montanie, Helene Hartmann, Hans Lebaron, P. Casamayor, E. O. Catala, P. Delmas, Daniel Éditeur(s) : Springer Résumé : Batch culture experiments using viral enrichment were conducted to test the response of a coastal bacterial community to autochthonous (i.e., co-existing) or allochthonous riverine viruses. The effects of viral infections on bacterial dynamics and activity were assessed by epifluorescence microscopy and thymidine incorporation, respectively, whereas the effect of viral infection on bacterial community composition was examined by polymerase chain reaction-single strand conformation polymorphism 16S ribosomal RNA fingerprinting. The percentages of high nucleic acid-containing cells, evaluated by flow cytometry, were significantly correlated (r (2) = 0.91, n = 12, p < 0.0001) to bacterial production, making this value a good predictor of active cell dynamics along the study. While confinement and temperature were the two principal experimental factors affecting bacterial community composition and dynamics, respectively, additions of freshwater viruses had significant effects on coastal bacterial communities. Thus, foreign viruses significantly reduced net bacterial population increase as compared to the enrichment treated with inactivated virus. Moreover, freshwater viruses recurrently and specifically affected bacterial community composition, as compared to addition of autochthonous viruses. In most cases, the combined treatment viruses and freshwater dissolved organic matter helped to maintain or even enhance species richness in coastal bacterial communities in agreement to the 'killing the winner' hypothesis. Thus, riverine virus input could potentially influence bacterial community composition of the coastal bay albeit with modest modification of bulk bacterial growth. Microbial Ecology (0095-3628) (Springer), 2009-02 , Vol. 57 , N. 2 , P. 295-306 Droits : 2009 Springer http://archimer.ifremer.fr/doc/2009/publication-6636.pdf DOI:10.1007/s00248-008-9428-1 http://archimer.ifremer.fr/doc/00000/6636/ | Partager |
![]() | Post-Traumatic Stress Disorder among Incomers in Remire-Montjoly Prison, French Guiana ; Le Trouble de Stress Post-traumatique parmi les Détenus en Centre Pénitentiaire en Guyane Française Auteur(s) : Arnal, Romain Ayhan, Gülen Pinganaud, Éric Basurko, Célia Jehel, Louis Auteurs secondaires : Service de psychiatrie et psychologie médicale et addictologie ; CHU de la Martinique Centre d'Investigation Clinique Antilles-Guyane (CIC - Antilles Guyane) ; Université des Antilles et de la Guyane (UAG) - Institut National de la Santé et de la Recherche Médicale (INSERM) - CHU de Pointe-à-Pitre - Centre Hospitalier de Cayenne Andrée Rosemon - CHU de Fort de France Unité fonctionnelle de psychiatrie intra-carcérale (UFPI) ; Centre Hospitalier de Cayenne Andrée Rosemon Centre de recherche en épidémiologie et santé des populations (CESP) ; Université de Versailles Saint-Quentin-en-Yvelines (UVSQ) - Université Paris-Sud - Paris 11 (UP11) - Assistance publique - Hôpitaux de Paris (AP-HP) - Hôpital Paul Brousse - Institut National de la Santé et de la Recherche Médicale (INSERM) Université des Antilles (Pôle Martinique) ; Université des Antilles (UA) Éditeur(s) : HAL CCSD Résumé : International audience Despite the recent interest in psychiatric illness in prison, the psychopathology of the Remire-Montjoly prison population remains largely unknown. Subject to significant population movements, French Guiana and its prison houses a very mixed population in which recent history has left a strong mark (earthquake in Haïti, civil war in Suriname, violence related to gold mining population and drug trafficking). These negative life events appear as potential vectors of psychological trauma. Additionally, strong links have been established in the literature between post-traumatic stress disorder (PTSD) and many other psychiatric disorders, including suicidal behavior and addictions. Under these conditions, we felt it essential to focus on the identification of PTSD in this sensitive population.Through adapted reception interviews, we tried to identify the PTSD, to describe by means of socio-demographic factors the studied population and to detect psychiatric comorbidities. The screening tool was the M.I.N.I. 5.0, which identifies 17 psychiatric disorders including the PTSD, based on the DSM IV definition. The target population was the prison incomers, agreeing to participate in the study, aged more than 18 years old and imprisoned between 18 January 2013 and 31 December 2013. To this date, 549 inmates were included in the study.The main result of this study was a prevalence of PTSD of 17% for incomers in detention. We found that the PTSD+ population is more likely to be female (15% against 7% p = 0.0246), which is consistent with the literature data. The M.I.N.I. 5.0 showed a higher prevalence of psychiatric disorders in the PTSD+ group. This association was confirmed in several types of pathology like mood disorders including: major depressive episode and manic or hypomanic episode, suicidal risk, some anxiety disorders including: panic disorder, obsessive-compulsive disorder and generalized anxiety disorder. Strong association was found for current major depressive episode, current manic or hypomanic episode and suicidal risk (p < 0.005).The prevalence of PTSD is very high in this study, about 24 times higher than in a general population survey using the same screening tool.A large number of comorbidities have been identified, which corresponds to those described in the literature. The specific issues of psychiatry in prison lead us to examine more specifically the significance of the results about suicide risk. A comprehensive suicide risk (sum of medium and high risk screened by the M.I.N.I.) was found in significantly more PTSD+ inmates (17% versus 7%, p = 0.005). This study supports the need for routine screening of PTSD among incomers in detention. This disease is both worrying and common in this population but the real issues are the comorbidities. Suicidal potential is among the most important issues in detention. Its evaluation should be completed by an early recognition of a PTSD. Soumis à des mouvements de population importants, la Guyane Française et son centre pénitentiaire abritentune population métissée chez qui l’histoire récente a laissé une empreinte forte (tremblement de terre en Haïti,guerre civile au Suriname, violence liée à l’orpaillage et au trafic de stupéfiants). Ces événements de vienégatifs apparaissent comme autant de vecteurs potentiels de psychotraumatismes. Dans ces conditions, il nous a paru essentiel de mettre l’accent sur le repérage du TSPT (Trouble de Stress Post-traumatique) dans cette population sensible. A l'aide d’entretiens d’accueil dédiés nous nous sommes proposé de repérer les TSPT, de décrire sur un plan sociodémographique la population étudiée et de rechercher les comorbidités psychiatriques. Le résultat principal de cette étude était une prévalence du TSPT de 17% chez les arrivants en détention. Le MINI 5.0 a montré une prévalence plus élevée des pathologies psychiatriques dans le groupe présentant un TSPT avec un lien très fort (p<0.005) pour l’épisode dépressif majeur actuel, l’épisode (hypo)maniaque actuel et le risque suicidaire. Cette étude appuie la nécessité d’avoir un dépistage systématique du TSPT chez les arrivants en détention. Cette pathologie est à la fois fréquente dans cette population et invalidante mais ce sont ses comorbidités, dont le potentiel suicidaire, qui font tout l’enjeu d’un repérage précoce. ISSN: 0383-6320 inserm-01421075 http://www.hal.inserm.fr/inserm-01421075 http://www.hal.inserm.fr/inserm-01421075/document http://www.hal.inserm.fr/inserm-01421075/file/2016%2C%20Arnal%20-%20Post-Traumatic%20Stress%20Disorder%20among%20Incomers%20in%20Remire-Montjoly%20Prison%2C%20French%20Guiana.pdf PUBMED : 27570960 | Partager |
![]() | Alkaline volcanism associated with early stage of rifting : East African Rift, Tanzania, Manyara basin ; Volcanisme alcalin associé à l'initiation de la rupture continentale : Rift Est Africain, Tanzanie, bassin de Manyara Auteur(s) : Baudouin, Céline Auteurs secondaires : Géosciences Montpellier ; Université des Antilles et de la Guyane (UAG) - Institut national des sciences de l'Univers (INSU - CNRS) - Université de Montpellier (UM) - Centre National de la Recherche Scientifique (CNRS) Université Montpellier Fleurice Parat Christel Tiberi Éditeur(s) : HAL CCSD Résumé : East African Rift (EAR) is the divergent plate boundary. EAR exposes different stages of extension, from early stage rifting in Tanzania to oceanic accretion in Afar (Ethiopia). Manyara basin is the southernmost rift system of the east branch of EAR with recent volcanism (< 1.5 Ma) and a seismic swarm in the lower crust (20 – 40 km). Due to its location and tectonic setting, the Manyara basin offers the opportunity to study the earliest stage of rift initiation. Manyara volcanism is composed of several types of hyper-alkaline lavas as Mg-nephelinites (Mg# > 55) (Labait, Kwaraha), calciocarbonatite (Kwaraha) and evolved nephelinites (Mg# < 35) (Hanang).Mg-nephelinites (Labait and Kwaraha) are primary lavas mainly composed of olivine and clinopyroxene (cpx). Geochemical modelling from trace elements suggests that these primary magmas result from a degree of partial melting < 1 % from a CO2-garnet-phlogopite-bearing peridotite. These magmas have an asthenospheric source at depth > 120 km (lava carries xenoliths with equilibrium conditions > 4 GPa). The minerals were crystallized from a magma with a low H2O content (0.1 and 0.5 wt% H2O). The calciocarbonatite and evolved nephelinites are derived from Mg-nephelinites by fractional crystallization and immiscibility processes. Hanang nephelinites are silica- and alkaline-rich lavas (44.2 – 46.7 wt % SiO2, 9.5 –12.1 wt % Na2O+K2O, respectively) composed by cpx, Ti-garnet, nepheline, apatite and titanite. Complex zonation of cpx (e.g. abrupt change of Mg#, Nb/Ta, and H2O) and trace element patterns of nephelinites record magmatic differentiation involving open system with carbonate-silicate immiscibility and primary melt replenishment. The low H2O content of cpx (3 – 25 ppm wt. H2O) indicates that at least 0.3 wt % H2O was present at depth during carbonate-rich nephelinite crystallization at 340 – 640 MPa and 1050 – 1100 °C. The study of hosted-nepheline melt inclusions from Hanang allows constraining the late magmatic evolution of nephelinites during storage and magma ascent. Melt inclusions are composed by a silicate trachytic glass, a carbonate phase and a shrinkage bubble. Trachytic glass contains high content in CO2 (0.43 wt %, SIMS analyses), sulfur (0.21 – 0.92 wt % S), chlorine (0.28 –0.84 wt % Cl) and H2O low content (< 0.1 wt %, Raman analyses). Immiscibility process leading to the formation of carbonate occurs in a closed system during rapid magma ascent between 200 – 500 MPa. The carbonate phase is a Ca-Na-K-S-rich and anhydrous carbonate (33 wt % CaO, 20 wt % Na2O, 3 wt % K2O, and 3 wt % S). The pre-immiscible liquid has a phonolitic composition with 6 ± 1.5 wt % CO2 at 700 MPa. A preliminary study of melt inclusions by XANES spectroscopy and whole rocks by Mössbauer spectroscopy was used to determine these Manyara lavas were formed at oxidizing conditions (~ ΔFMQ +1.5).The early stage rifting volcanism (Manyara Basin) is characterized by CO2-rich and H2O-poor magmas from at least 120 km below the rift escarpment. The presence of CO2-rich magmas and the small amount of volcanic rocks erupted at the surface may indicate that the storage and percolation of these magmas at depth is a potential trigger for deep seismic swarms. Le rift Est africain (REA) est une frontière de plaque en extension. Ce rift présente plusieurs stades d’extension, de l’initiation du rift en Tanzanie jusqu’à l’accrétion océanique en Afar. Le bassin de Manyara se situe le plus au sud de branche Est du REA. Il est caractérisé par la présence de volcanisme récent (< 1,5 Ma) et d’un essaim sismique dans la croûte inférieure (20 – 40 km). De par sa localisation et son contexte tectonique, le bassin de Manyara offre l’opportunité d’étudier le stade le plus précoce de l’initiation du rift. Le bassin de Manyara est composé de plusieurs types de laves hyperalcalines, les néphélinites magnésiennes (Mg# > 55) (Labait, Kwaraha), de calciocarbonatite (Kwaraha) et des néphélinites différenciées (Mg# < 35) (Hanang).Les néphélinites magnésiennes (Labait et Kwaraha) sont des laves primaires composées d’olivines et de clinopyroxènes (cpx). La modélisation géochimique des éléments en trace suggère que ces magmas primaires résultent d'un degré de fusion partielle ≤ 1 % à partir d'une péridotite à grenat et phlogopite. Ces magmas proviennent d’une profondeur > 120 km (présence de xénolites avec des conditions d’équilibre > 4 GPa). Les minéraux ont cristallisés à partir d’un magma pauvre en eau (0,1 et 0,5 pds % H2O). La calciocarbonatite et les néphélinites différenciés sont issues des néphélinites magnésiennes par cristallisation fractionnée et processus d’immiscibilité. Les néphélinites du Hanang sont riches en éléments alcalins (9,5 – 12,1 pds % Na2O+K2O) et en silice (44,2 – 46,7 pds% SiO2) et sont composés de cpx, grenat, néphéline, titanite et apatite. La zonation complexe dans les cpx (par exemple, changement brusque de Mg#, Nb/Ta, et H2O) implique une différenciation magmatique en système ouvert avec immiscibilité de liquide carbonaté et silicaté ainsi qu’un remplissage de la chambre magmatique avec des liquides primaires. La faible teneur en eau des cpx (3 – 25 ppm H2O) indique la présence d’un magma pauvre en eau (0,3 pds % H2O) lors de la cristallisation des cpx à des conditions crustales (340 – 640 MPa et 1050 – 1100 °C). L’étude des inclusions vitreuses dans les néphélines de Hanang permet de contraindre l'évolution magmatique tardive des néphélinites et le comportement des éléments volatils (CO2, H2O, S, F, Cl) lors du stockage et de la remontée du magma. Les inclusions vitreuses sont composées d’un verre trachytique, d’une phase carbonatée et d’une bulle de rétraction. Le verre trachytique contient du CO2 (0,43 pds % CO2, analyses SIMS), du soufre (0,21 à 0,92 pds% S), du chlore (0,28 – 0,84 pds % Cl) et très peu d’H2O (< 0,1 pds % H2O, analyses Raman). Le processus d’immiscibilité conduisant à la formation du carbonate se produit dans un système fermé pendant l'ascension rapide du magma, entre 200 – 500 MPa. La phase carbonatée est un carbonate anhydre et riche en Ca-Na-K-S (33 pds % CaO, 20 pds % Na2O, 3 pds % K2O, et 3 pds % S). Le liquide pré-immiscible a une composition phonolitique avec 6 ± 1,5 pds % CO2 à une pression de 700 MPa. Une étude préliminaire des inclusions par spectroscopie XANES et des roches par spectroscopie Mössbauer a permis de déterminer que les laves de Manyara se sont formées à conditions oxydantes (~ ∆FMQ +1,5).À l’initiation du rift, le volcanisme dans le bassin de Manyara est caractérisé par des magmas riches en CO2 et pauvres en H2O issus d’au moins 120 km de profondeur sous l'escarpement du rift. La présence de ces magmas riches en CO2 et la faible quantité de roches volcaniques émises à la surface peuvent indiquer que le piégeage et la percolation de ces magmas en profondeur est un déclencheur potentiel des essaims sismiques profonds. https://tel.archives-ouvertes.fr/tel-01563231 NNT : 2016MONTT114 tel-01563231 https://tel.archives-ouvertes.fr/tel-01563231 https://tel.archives-ouvertes.fr/tel-01563231v2/document https://tel.archives-ouvertes.fr/tel-01563231/file/2016_BAUDOUIN_archivage.pdf | Partager |
![]() | Invasion Is a Community Affair: Clandestine Followers in the Bacterial Community Associated to Green Algae, Caulerpa racemosa, Track the Invasion Source Auteur(s) : Aires, Tania Serrao, Ester A. Kendrick, Gary Duarte, Carlos M. Arnaud-haond, Sophie Éditeur(s) : Public Library Science Résumé : Biological invasions rank amongst the most deleterious components of global change inducing alterations from genes to ecosystems. The genetic characteristics of introduced pools of individuals greatly influence the capacity of introduced species to establish and expand. The recently demonstrated heritability of microbial communities associated to individual genotypes of primary producers makes them a potentially essential element of the evolution and adaptability of their hosts. Here, we characterized the bacterial communities associated to native and non-native populations of the marine green macroalga Caulerpa racemosa through pyrosequencing, and explored their potential role on the strikingly invasive trajectory of their host in the Mediterranean. The similarity of endophytic bacterial communities from the native Australian range and several Mediterranean locations confirmed the origin of invasion and revealed distinct communities associated to a second Mediterranean variety of C. racemosa long reported in the Mediterranean. Comparative analysis of these two groups demonstrated the stability of the composition of bacterial communities through the successive steps of introduction and invasion and suggested the vertical transmission of some major bacterial OTUs. Indirect inferences on the taxonomic identity and associated metabolism of bacterial lineages showed a striking consistency with sediment upheaval conditions associated to the expansion of their invasive host and to the decline of native species. These results demonstrate that bacterial communities can be an effective tracer of the origin of invasion and support their potential role in their eukaryotic host's adaptation to new environments. They put forward the critical need to consider the 'meta-organism' encompassing both the host and associated micro-organisms, to unravel the origins, causes and mechanisms underlying biological invasions. Plos One (1932-6203) (Public Library Science), 2013-07 , Vol. 8 , N. 7 , P. - Droits : 2013 Aires et al. This is an open-access article distributed under the terms of the Creative Commons Attribution License, which permits unrestricted use, distribution, and reproduction in any medium, provided the original author and source are credited. http://archimer.ifremer.fr/doc/00157/26791/24886.pdf DOI:10.1371/journal.pone.0068429 http://archimer.ifremer.fr/doc/00157/26791/ | Partager |
![]() | Larval Dispersal Modeling of Pearl Oyster Pinctada margaritifera following Realistic Environmental and Biological Forcing in Ahe Atoll Lagoon Auteur(s) : Thomas, Yoann Dumas, Franck Andrefouet, Serge Éditeur(s) : Public Library Science Résumé : Studying the larval dispersal of bottom-dwelling species is necessary to understand their population dynamics and optimize their management. The black-lip pearl oyster (Pinctada margaritifera) is cultured extensively to produce black pearls, especially in French Polynesia's atoll lagoons. This aquaculture relies on spat collection, a process that can be optimized by understanding which factors influence larval dispersal. Here, we investigate the sensitivity of P. margaritifera larval dispersal kernel to both physical and biological factors in the lagoon of Ahe atoll. Specifically, using a validated 3D larval dispersal model, the variability of lagoon-scale connectivity is investigated against wind forcing, depth and location of larval release, destination location, vertical swimming behavior and pelagic larval duration (PLD) factors. The potential connectivity was spatially weighted according to both the natural and cultivated broodstock densities to provide a realistic view of connectivity. We found that the mean pattern of potential connectivity was driven by the southwest and northeast main barotropic circulation structures, with high retention levels in both. Destination locations, spawning sites and PLD were the main drivers of potential connectivity, explaining respectively 26%, 59% and 5% of the variance. Differences between potential and realistic connectivity showed the significant contribution of the pearl oyster broodstock location to its own dynamics. Realistic connectivity showed larger larval supply in the western destination locations, which are preferentially used by farmers for spat collection. In addition, larval supply in the same sectors was enhanced during summer wind conditions. These results provide new cues to understanding the dynamics of bottom-dwelling populations in atoll lagoons, and show how to take advantage of numerical models for pearl oyster management. Plos One (1932-6203) (Public Library Science), 2014-04 , Vol. 9 , N. 4 , P. e95050 Droits : 2014 Thomas et al. This is an open-access article distributed under the terms of the Creative Commons Attribution License, which permits unrestricted use, distribution, and reproduction in any medium, provided the original author and source are credited http://archimer.ifremer.fr/doc/00197/30843/29210.pdf DOI:10.1371/journal.pone.0095050 http://archimer.ifremer.fr/doc/00197/30843/ | Partager |
![]() | Yield surfaces and plastic potentials of cemented granular materials from discrete element simulations Auteur(s) : Estrada, Nicolas Taboada, Alfredo Auteurs secondaires : Universidad de los Andes [Bogota] Risques ; Géosciences Montpellier ; Université des Antilles et de la Guyane (UAG) - Institut national des sciences de l'Univers (INSU - CNRS) - Université de Montpellier (UM) - Centre National de la Recherche Scientifique (CNRS) - Université des Antilles et de la Guyane (UAG) - Institut national des sciences de l'Univers (INSU - CNRS) - Université de Montpellier (UM) - Centre National de la Recherche Scientifique (CNRS) Éditeur(s) : HAL CCSD Elsevier Résumé : This paper presents a numerical investigation on the mechanical behavior of cemented granular materials by means of discrete element simulations. In particular, two conceptual elements of this behavior were explored: the yield surfaces and the plastic potentials, as defined in the framework of elastoplastic constitutive models. For this purpose, we implemented a contact model that mimics the mechanical behavior of cemented bonds, we constructed a set of polydisperse samples with different solid fractions, and we tested these samples by means of a biaxial device with four rigid walls. The yield surfaces and plastic potentials were thus obtained and analyzed as functions of the solid fraction of the material, drawing interesting conclusions, confirming previous experimental findings, and, consequently, evidencing the great potential of discrete element simulations in exploring the behavior of real cemented geomaterials. ISSN: 0266-352X hal-00853748 https://hal.archives-ouvertes.fr/hal-00853748 DOI : 10.1016/j.compgeo.2012.11.001 | Partager Voir aussi Granular materials Cementation Elastoplasticity Yield surface Plastic potential Flow rule Discrete element method [SDU.STU.GP] Sciences of the Universe [physics]/Earth Sciences/Geophysics [physics.geo-ph] [PHYS.PHYS.PHYS-GEO-PH] Physics [physics]/Physics [physics]/Geophysics [physics.geo-ph] [SDE.MCG] Environmental Sciences/Global Changes |
![]() | Evaluation of P-Glycoprotein Inhibitory Potential Using a Rhodamine 123 Accumulation Assay Auteur(s) : Jouan, Elodie Le Vée, Marc Mayati, Abdullah Denizot, Claire Parmentier, Yannick FARDEL, Olivier Auteurs secondaires : Institut de recherche, santé, environnement et travail [Rennes] (Irset) ; Université d'Angers (UA) - Université des Antilles et de la Guyane (UAG) - Université de Rennes 1 (UR1) - École des Hautes Études en Santé Publique [EHESP] (EHESP) - Institut National de la Santé et de la Recherche Médicale (INSERM) - Structure Fédérative de Recherche en Biologie et Santé de Rennes ( Biosit : Biologie - Santé - Innovation Technologique ) Technologie Servier ; Technologie Servier CHU Pontchaillou [Rennes] Éditeur(s) : HAL CCSD Résumé : International audience In vitro evaluation of P-glycoprotein (P-gp) inhibitory potential is now a regulatory issue during drug development, in order to predict clinical inhibition of P-gp and subsequent drug-drug interactions. Assays for this purpose, commonly based on P-gp-expressing cell lines and digoxin as a reference P-gp substrate probe, unfortunately exhibit high variability, raising thus the question of developing alternative or complementary tests for measuring inhibition of P-gp activity. In this context, the present study was designed to investigate the use of the fluorescent dye rhodamine 123 as a reference P-gp substrate probe for characterizing P-gp inhibitory potential of 16 structurally-unrelated drugs known to interact with P-gp. 14/16 of these P-gp inhibitors were found to increase rhodamine 123 accumulation in P-gp-overexpressing MCF7R cells, thus allowing the determination of their P-gp inhibitory potential, i.e., their half maximal inhibitor concentration (IC50) value towards P-gp-mediated transport of the dye. These IC50 values were in the range of variability of previously reported IC50 for P-gp and can be used for the prediction of clinical P-gp inhibition according to Food and Drug Administration (FDA) criteria, with notable sensitivity (80%). Therefore, the data demonstrated the feasibility of the use of rhodamine 123 for evaluating the P-gp inhibitory potential of drugs Pharmaceutics hal-01305488 https://hal-univ-rennes1.archives-ouvertes.fr/hal-01305488 DOI : 10.3390/pharmaceutics8020012 PUBMED : 27077878 | Partager |
![]() | Effet des conditions environnementales sur le développement des pathologies à Vibrio dans les élevages de crevettes en Nouvelle-Calédonie Auteur(s) : Lemonnier, Hugues Éditeur(s) : Université de La Rochelle Résumé : Shrimp aquaculture in New Caledonia is a developing industry, exclusively based on the species Litopenaeus stylirostris. However, it is subject to mortalities during grow out as observed all over the world. Since 1993, shrimp reared during the cold period are affected by a disease named "syndrome 93". As a consequence, the whole industry has become seasonal and produces essentially during the warm season. The climatic conditions during the periods of transition between the two main seasons could be responsible for an environmental stress and the origin reason for mortality outbreaks. Stocking density is the main risk factor. It increases the probability of the appearance and development of the epizooty in the pond. The "Summer Syndrome", a septicemic vibriosis caused by Vibrio nigripulchritudo, was identified for the first time in December 1997 in an intensive shrimp farm (DF). It has become enzootic ever since and is expressed after 50d of rearing. Since 2003, two others farms located near DF have developed the disease. As a consequence, the summer syndrome is considered to be a potential threat for all the industry. Between 1991 and 2005, the increase of feed input and nitrogen levels in feed has led to a significant increase in the growth rate over the years in the farms affected by the disease. In consequence, an early eutrophication of the water is observed, which is concomitant with the beginning of the mortality outbreaks. An early eutrophication and the virulence level of the pathogen are considered as the main risk factors of the disease. Factors may act synergistically to explain the summer syndrome. As part of a multidisciplinary approach (pathology physiology environment), two high-frequency surveys were carried out to analyse the pond ecosystem. Since the feed quantity increases with the biomass of shrimp, the eutrophication level of the pond ecosystem will also tend to increase with the duration of rearing. During the first part of the rearing, the abundance of each picoplankton type is exceptionally high and picophytoplankton dominated the autotrophic compartment. The nanophytoplankton dominated the second part of the rearing and was more unstable. The shift from pico to nanophytoplankton could be considered as an environmental stress and was observed in relation to the beginning of the mortalities, whatever the disease. Shift intensity could play a role by inducing directly or indirectly a stress for shrimp and/or a growth and/or virulence factors of the pathogen. Results from sediment studies show that mortality was best characterized by TAN concentration in pore water and even more when the TAN concentration was high. TAN and pH are potential stress factors for shrimp reared in ponds affected by these diseases. L'aquaculture mondiale de crevettes est un secteur à très forte croissance. Toutefois, les problèmes liés aux maladies dans les élevages ne cessent d'augmenter depuis 1980. Au cours du développement de la filière de Nouvelle-Calédonie, deux épisodes saisonniers de mortalités associées à la présence de Vibrio pathogènes sont apparus et ont fortement perturbé les techniques et les schémas de production. Les premières mortalités hivernales, décrites sous le nom de « syndrome 93 » ont été observées en mai 1993. Elles ont affecté depuis tous les élevages de saison froide de toutes les fermes de production. Les conditions climatiques pendant les périodes de transitions entre les deux principales saisons caractérisant le climat de la Nouvelle-Calédonie, seraient responsables d'un stress environnemental à l'origine du déclenchement du syndrome 93. La densité initiale d'ensemencement, apparaît comme le principal facteur de risque, augmentant la probabilité d'apparition de la maladie et l'ampleur de ses effets. Le « syndrome d'été » a été identifié pour la première fois en 1997 dans une ferme pratiquant une production intensive. Il s'est déclaré depuis 2003 dans deux autres fermes géographiquement proches. Les mortalités apparaissent 58 jours en moyenne après l'ensemencement des post-larves dans les bassins. La recherche d'une croissance maximale des animaux a induit, avec les années, une intensification progressive du système caractérisée par une augmentation de la quantité d'aliment distribuée. L'examen des données historiques fait apparaître une eutrophisation du milieu de plus en plus précoce concomitante au déclenchement des mortalités. En l'état actuel de nos connaissances, cette évolution précoce de l'écosystème en présence de façon récurrente de la souche hautement pathogène du Vibrio incriminé et à une période où la fréquence des mues des crevettes est élevée, constitue le principal facteur de risque de la maladie. Avec l'apport croissant en aliment, la colonne d'eau évolue vers une autotrophie croissante alors que le sédiment devient de plus en plus hétérotrophe au fur et à mesure que l'élevage progresse. Au cours du processus d'eutrophisation, le compartiment autotrophe montre une succession de deux assemblages. Le picophytoplancton domine sur la première partie de l'élevage et laisse place à du nanophytoplancton en seconde partie. Cette phase de transition, concomitante à l'apparition des mortalités quel que soit le syndrome, caractérise un stress environnemental dont l'intensité pourrait favoriser ou non le déclenchement des mortalités. Les suivis de différents indicateurs dans les sédiments - pH, potentiel d'oxydoréduction et concentration en ammoniaque dans l'eau interstitielle indiquent dans les bassins déclarant les épizooties des conditions qui ont été définies expérimentalement comme potentiellement plus stressantes pour les animaux. Droits : info:eu-repo/semantics/openAccess http://archimer.ifremer.fr/doc/2007/these-2643.pdf http://archimer.ifremer.fr/doc/00000/2643/ | Partager |
![]() | Seasonal Pattern of the Biogeochemical Properties of Mangrove Sediments Receiving Shrimp Farm Effluents (New Caledonia) Auteur(s) : Marchand, Cyril Molnar, N. Deborde, Jonathan Della Patrona, Luc Meziane, Tarik Éditeur(s) : OMICS Publishing Group Résumé : Coastal tropical shrimp farming may impact the adjacent ecosystems through the release of large quantities of effluents rich in nutrients. In New Caledonia, mangroves are considered as a natural biofilter to reduce impacts on the surrounding World Heritage listed lagoon. Our main objective was to understand the influence of effluent discharge on the biogeochemistry of mangrove sediments. A monitoring of the physico-chemical parameters of mangrove sediments was carried out during a whole year, including active and non active periods of the farm. The parameters studied were: i) benthic primary production (Chl-a concentrations), ii) physico-chemical parameters of sediments (redox potential, pH, salinity, TOC, TN, TS, δ13C and δ15N), iii) concentrations of dissolved nitrogen, iron and phosphorus. A mangrove developing in the same physiographic conditions, presenting the same zonation, and free of anthropogenic input was used as reference. The concentration of benthic Chl-a measured at sediment surface in the effluent receiving mangrove was twice to three times that measured in the control zone whatever the season. We thus suggest that nutrients inputs significantly increased the phytobenthic production in the effluent receiving mangrove during the whole year, even after the cessation of discharges and because of natural seasonal dynamic of phytobenthos. Although the flow of surface OM was increased, the OM content at depth was not higher than in the control mangrove. However, the contribution of mangrove detritus to the sedimentary organic pool was higher probably as a result of higher density and much greater individual size of the mangrove trees. Unlike the control mangrove sediment, the effluent receiving mangrove sediment was not stratified, redox potential values were high and presence of Fe3+ was detected down to 50 cm depth, probably as a result of a larger root system, allowing a better sediment oxygenation and accentuated OM decomposition processes, and thus limiting ecosystem saturation. Journal of Aquaculture Research & Development (21559546) (OMICS Publishing Group), 2014-07-03 , Vol. 5 , N. 5 , P. 1-13 Droits : 2014 Marchand C, et al. This is an open-access article distributed under the terms of the Creative Commons Attribution License, which permits unrestricted use, distribution, and reproduction in any medium, provided the original author and source are credited. http://archimer.ifremer.fr/doc/00251/36253/34801.pdf DOI:10.4172/2155-9546.1000262 http://archimer.ifremer.fr/doc/00251/36253/ | Partager |
![]() | Langoustes et scyllares des petites Antilles Auteur(s) : Morice, Jean Éditeur(s) : ISTPM Résumé : Crayfishing is not particularly organized in the French islands as their population is not fond of large crustaceans. However, young crayfishes, about the size of the European scampi are ordered by rich Creoles for receptions or family gatherings. But lobsters, heavier than 0.750 to 1 kilo are eaten only by Europeans.Any fisherman who is asked to provide 10 kilos of crayfish catches them very quickly with a brass snare or a hook placed underneath the rocks. Some artisans gather the crustaceans in large rectangular baskets made of wire mesh and called "gardes", to wait for the potential customer. There is no specific pot for this type of fishing whereas Creole wicker makers worked hard on the creation of tools both complex and difficult to make to catch small morays; a fish which does not have a great commercial value.Consequently, it is impossible to precisely assess the importance of the exploitable large crustacean stock based on the catches of the Creole fishermen. If the performances of some crayfish boats from Douarnenez, using Mauritanian nets on the banks of St-Martin, can be considered as extremely satisfactory, it is not the case of other attempts. A whole study has to be undertaken. This note is only the beginning of a larger work focusing on the natural history of the crayfishes and Spanish lobsters in the waters of the arc of the Petites Antilles. La pêche des langoustes n'est pas spécialement organisée dans les îles françaises, la population n'étant que peu friande de gros crustacés. Toutefois de jeunes langoustes, de la taille de la langoustine européenne sont commandées aux pêcheurs par les riches créoles, à l'occasion de réceptions ou de fêtes familiales; mais les « homards») dépassant le poids de 0,750 à 1 kilo sont consommés seulement par les Européens. Le pêcheur. auquel on demande de fournir 10 kilos de langoustes, les capture rapidement au collet de laiton ou au crochet sous les cayes, Certains artisans rassemblent les crustacés dans de grandes nasses rectangulaires de grillage métallique, appelées « gardes », en attendant l'acheteur éventuel. Il n'existe pas de type de casier spécial à cette pêche, alors que les vanniers créoles se sont ingéniés, par exemple, à créer des engins compliqués et difficiles à construire pour capturer les petites murènes appelées « moringues » qui n'ont pourtant que peu de valeur commerciale. Il est donc impossible de se faire une idée précise de l'importance du stock de gros crustacés exploitable en se basant sur les apports des pêcheurs créoles. Si les rendements de certains langoustiers douarnenistes, travaillant au filet mauritanien sur les bancs de St-Martin, ont pu être considérés comme extrêmement satisfaisants, il n'en est pas de même à propos d'autres tentatives. Il y a là toute une étude à entreprendre. Cette note n'est que le début d'un travail concernant l'histoire naturelle des langoustes et scyllares des eaux de l'arc des Petites Antilles. [OCR NON CONTRÔLE] Revue des Travaux de l'Institut des Pêches Maritimes (0035-2276) (ISTPM), 1958-03 , Vol. 22 , N. 1 , P. 105-114 Droits : Ifremer http://archimer.ifremer.fr/doc/1958/publication-4567.pdf http://archimer.ifremer.fr/doc/00000/4567/ | Partager |
![]() | The transition zone between the Pernambuco-Alagoas Domain and the Sergipano Belt (Borborema Province, NE Brazil): Geochronological constraints on the ages of deposition, tectonic setting and metamorphism of metasedimentary rocks Auteur(s) : Neves, Sergio p. Rangel Da Silva, Jose Mauricio BRUGUIER, Olivier Auteurs secondaires : Universidade Federal de Pernambuco, Recife Géosciences Montpellier ; Université des Antilles et de la Guyane (UAG) - Institut national des sciences de l'Univers (INSU - CNRS) - Université de Montpellier (UM) - Centre National de la Recherche Scientifique (CNRS) Dynamique de la Lithosphere ; Géosciences Montpellier ; Université des Antilles et de la Guyane (UAG) - Institut national des sciences de l'Univers (INSU - CNRS) - Université de Montpellier (UM) - Centre National de la Recherche Scientifique (CNRS) - Université des Antilles et de la Guyane (UAG) - Institut national des sciences de l'Univers (INSU - CNRS) - Université de Montpellier (UM) - Centre National de la Recherche Scientifique (CNRS) Éditeur(s) : HAL CCSD Elsevier Résumé : International audience Metasedimentary rocks in the transition zone between the Pernambuco-Alagoas Domain and the Sergipano Belt (southern Borborema Province, NE Brazil) were studied in order to place constraints on the geological evolution of this portion of West Gondwana. High-grade metamorphic conditions are recorded by the garnet-sillimanite assemblage and common anatexis in pelitic paragneisses. Two samples dated by LA-ICP-MS in the north yielded a predominance of early Neoproterozoic detrital zircons, with age peaks between 990 Ma and 827 Ma, with the youngest grain suggesting deposition after 670 Ma. Low Th/U zircons (Th/U < 0.1) in these samples display a significant spread in ages, from 691 to 568 Ma. One sample in the south is dominated by a homogenous population of Paleoproterozoic grains, with a 2200 Ma peak. The southernmost sample also contains Paleoproterozoic zircons but the most abundant population is Neoproterozoic, and characterized by age peaks at c. 670, 647 and 623 Ma. These results show that deposition of sediments in the southern PEAL Domain and in the northern Sergipano Belt occurred in the Late Neoproterozoic. The differing age spectra between samples are correlated with potential source rocks in the study area or in its proximity, reflecting variable input from local sources. The data are interpreted to indicate that during the course of an extensional event at c. 673-647 Ma, Tonian granitic intrusions and synextensional metamorphic rocks were unroofed and eroded to provide zircons for sediments deposited in the north, whereas Paleoproterozoic and synextensional magmatic rocks were the main sources for sediments in the south. Peak metamorphic conditions and contractional deformation are constrained to c. 630-600 Ma. ISSN: 0895-9811 hal-01468011 https://hal.archives-ouvertes.fr/hal-01468011 DOI : 10.1016/j.jsames.2016.09.010 | Partager |
![]() | Analyzing the market position of fish species subject to the impact of long-term changes: a case study of French fisheries in the Bay of Biscay Auteur(s) : Le Floc' H, P Poulard, Jean-charles Thebaud, Olivier Blanchard, Fabian Bihel, J Steinmetz, Fabien Éditeur(s) : EDP Sciences Résumé : Market position and its evolution were analysed in nine key fish and cephalopod species subject to long-term changes, using the Bay of Biscay fisheries as a case study. Although such long term changes have already been documented, and in some cases shown to be related to the impacts of fishing, changes in the physical environment, or both, relatively little work has been devoted to their potential consequences in economic terms. The nature and extent of these consequences was determined in the present study by looking at the composition of the affected fish production, and the status of different fish products on the markets. We propose a methodology to characterize market position for this set of nine species. The selected species represent a significant part of the gross turnover of French fishing fleets operating in the bay. These species were characterized in terms of their potential sensitivity to fishing and changes in environmental conditions due to global warming. We separated species potentially positively (Engraulis encrasicolus and Lophius budegassa) and negatively affected (Pollachius pollachius and Lophius piscatorius) by warming. Evolution of the value of production of the nine species was then depicted using analysis of macro-economic index (production and potential consumption) and price indices. This revealed the relatively high sensitivity of domestic production to the market crisis that occurred in France in the early 1990s, compared to imported and exported products. The relative position of individual species, with respect to the market and its evolution between 1990 and 2005, was analyzed by multi-factorial analysis. Results derived from the analysis clearly distinguish two groups of species, the first characterized by higher prices (monkfish, Nephrops, sole, seabass) and the second by larger volumes available on the French market (pollack, hake, anchovy, sardine, cuttlefish). We conclude that a major part (69 to 87%) of the gross turnover associated with catches of these fish species in the Bay of Biscay remains potentially unaffected by long-term changes related to climate. Aquatic Living Resources (0990-7440) (EDP Sciences), 2008-07 , Vol. 21 , N. 3 , P. 307-316 Droits : EDP Sciences, IFREMER, IRD 2008 http://archimer.ifremer.fr/doc/2008/publication-4716.pdf DOI:10.1051/alr:2008047 http://archimer.ifremer.fr/doc/00000/4716/ | Partager |