Automatic spawning detection in oysters: a fault detection approach
Using measurements of valve activity in a population of bivalves under natural environmental condition (16 oysters in the Bay of Arcachon, France), an algorithm for the automatic detection of spawning period of oysters is proposed. The algorithm is based on the fault detection approach and it works through the estimation of velocity of valves movement activity, which can be obtained by calculating the time derivative of the valves distance. A summarized description on the method used for the derivative estimation is provided, followed by the associated signal processing and decision making algorithm to determine spawning from the velocity signal. A protection from false spawning detection is also considered by analyzing the synchronicity in spawning. Through this study, it is shown that spawning in a population of oysters living in their natural habitat (i.e. in the sea) can be automatically detected without any human expertise, like visual analysis.
(17/07/2015)
NON-A, Inria, CRIStAL, CNRS, EPOC, EPHE, PSL, UB, INSU - CNRS, CNRS
Pinus nigra (European black pine) as the dominant species of the last glacial pinewoods in south-western to central Iberia: a morphological study of modern and fossil pollen
AimOur aim was to discriminate different species ofPinusvia pollen analysisin order to assess the responses of particular pine species to orbital and millen-nial-scale climate changes, particularly during the last glacial period.LocationModern pollen grains were collected from current pine populationsalong transects from the Pyrenees to southern Iberia and the Balearic Islands.Fossil pine pollen was recovered from the south-western Iberian margin coreMD95-2042.MethodsWe measured a set of morphological traits of modern pollen fromthe Iberian pine speciesPinus nigra,P. sylvestris,P. halepensis,P. pineaandP. pinasterand of fossil pine pollen from selected samples of the last glacialperiod and the early to mid-Holocene. Classification and regression tree(CART) analysis was used to establish a model from the modern dataset thatdiscriminates pollen from the different pine species and allows identification offossil pine pollen at the species level.ResultsThe CART model was effective in separating pollen ofP. nigraandP. sylvestrisfrom that of the Mediterranean pine group (P. halepensis,P. pineaandP. pinaster). The pollen ofPinus nigradiverged from that ofP. sylvestrisby having a more flattened corpus. Predictions using this model suggested thatfossil pine pollen is mainly fromP. nigrain all the samples analysed.Pinus syl-vestriswas more abundant in samples from Greenland stadials than Heinrichstadials, whereas Mediterranean pines increased in samples from Greenland in-terstadials and during the early to mid-Holocene.Main conclusionsMorphological parameters can be successfully used toincrease the taxonomic resolution of fossil pine pollen at the species level forthe highland pines (P. nigraandP. sylvestris) and at the group of species levelfor the Mediterranean pines. Our study indicates thatP. nigrawas the domi-nant component of the last glacial south-western/central Iberian pinewoods,although the species composition of these woodlands varied in response toabrupt climate changes.
(Journal of Biogeography. vol. 42, n° 0305-0270, pp. 1998-2009, 08/07/2015)
EPOC, EPHE, PSL, UB, INSU - CNRS, CNRS
Transferts et accumulations sur les marges du Golfe de Gascogne : architecture, fonctionnement et contrôles.
Ce travail présente une analyse de la morphologie et de la dynamique sédimentaire des systèmes turbiditiques actuels du Cap-Ferret et de Capbreton (sud du Golfe de Gascogne). La reconnaissance effectuée sur le système de Capbreton est la première à le considérer dans son ensemble. Ce travail se base sur des données acoustiques de subsurface (sondeur multifaisceaux, sondeur de sédiments Chirp) et de carottages issues de la campagne océanographique Sargass menée par l’Université de Bordeaux. L’analyse morpho-bathymétrique révèle l’organisation amont-aval des géométries sédimentaires dans ces systèmes et, couplée aux données sédimentaires, de préciser les processus de dépôts liés aux écoulements gravitaires. Le fonctionnement holocène du canyon de Capbreton montre des processus gravitaires haute fréquence, révélant son rôle de dépôt-centre pour le sud du golfe de Gascogne. Dans le système du Cap-Ferret, la zone de transition chenal-lobe a été investiguée à fine échelle, documentant ainsi des structures sédimentaires rarement identifiées avec ce niveau de détails dans les systèmes turbiditiques modernes. La dynamique sédimentaire de chacun de ces systèmes est soumise à des forçages auto-cycliques et glacio-eustatiques qui affectent chacun des systèmes de façons différentes. Ces informations ont permis de proposer un modèle régional de fonctionnement sédimentaire au cours des derniers 50 000 ans.
(08/07/2015)
EPOC, EPHE, PSL, UB, INSU - CNRS, CNRS
Genotoxic and immunotoxic potential effects of selected psychotropic drugs and antibiotics on blue mussel (Mytilus edulis) hemocytes.
The potential toxicity of pharmaceuticals towards aquatic invertebrates is still poorly understood and sometimes controversial. This study aims to document the in vitro genotoxicity and immunotoxicity of psychotropic drugs and antibiotics on Mytilus edulis. Mussel hemocytes were exposed to fluoxetine, paroxetine, venlafaxine, carbamazepine, sulfamethoxazole, trimethoprim and erythromycin, at concentrations ranging from μg/L to mg/L. Paroxetine at 1.5 μg/L led to DNA damage while the same concentration of venlafaxine caused immunomodulation. Fluoxetine exposure resulted in genotoxicity, immunotoxicity and cytotoxicity. In the case of antibiotics, trimethoprim was genotoxic at 200 μg/L and immunotoxic at 20 mg/L whereas erythromycin elicited same detrimental effects at higher concentrations. DNA metabolism seems to be a highly sensitive target for psychotropic drugs and antibiotics. Furthermore, these compounds affect the immune system of bivalves, with varying intensity. This attests the relevance of these endpoints to assess the toxic mode of action of pharmaceuticals in the aquatic environment.
(Environmental Pollution. vol. 202, n° 0269-7491, pp. 177-186, 01/07/2015)
INRS-AFSB, INRS, EPOC, EPHE, PSL, UB, INSU - CNRS, CNRS, LEMAR, IRD, IFREMER, UBO EPE, CNRS, UB
Responses of cytochrome P450, GST, and MXR in the mollusk Corbicula fluminea to the exposure to hospital wastewater effluents
Pharmaceutical products are a major group of chemical compounds that are continuously released into the environment. The primary pathway of pharmaceuticals to the aquatic environment is the discharge of wastewater effluents. The Psychiatric hospital of Montpon (Dordogne, France) operates with its wastewater treatment plant. We first evaluated the presence and concentrations of 27 pharmaceuticals compounds in these effluents. All of the 27 compounds were detected in these wastewater effluents at concentrations ranging between 37,500 ng L−1 (paracetamol) and 150 ng L−1 (citalopram). The aim of the study was then to evaluate the exposure effects of the effluents on cytochrome P450, GST, and MXR responses in Corbicula fluminea gills and digestive glands. Experiments on clams exposed during 1, 3, 7 14, and 21 days revealed a strong and continuous overexpression of mdr1 (multidrug resistant 1) gene expression in gills and transitory variations in pi-gst expression and GST activity. EROD activity increased also transitory after 1 day in the digestive gland of exposed clams. These results indicated that in the effluent, some molecules have undergone metabolism of phase 1 and/or phase 2.
(Environmental Science and Pollution Research. vol. 22, n° 0944-1344, pp. 11033-11046, 01/07/2015)
VAcBio, INUC, Comue de Toulouse, LECA, UJF, USMB [Université de Savoie] [Université de Chambéry], CNRS, EPOC, EPHE, PSL, UB, INSU - CNRS, CNRS, INUC, Comue de Toulouse, GEODE, UT2J, Comue de Toulouse, CNRS
The silicon isotope composition of Ethmodiscus rex laminated diatom mats from the tropical West Pacific: Implications for silicate cycling during the Last Glacial Maximum
The cause of massive blooms of Ethmodiscus rex laminated diatom mats (LDMs) in the eastern Philippine Sea (EPS) during the Last Glacial Maximum (LGM) remains uncertain. In order to better understand the mechanism of formation of E. rex LDMs from the perspective of dissolved silicon (DSi) utilization, we determined the silicon isotopic composition of single E. rex diatom frustules (δ 30 Si E. rex) from two sediment cores in the Parece Vela Basin of the EPS. In the study cores, δ 30 Si E. rex varies from À1.23‰ to À0.83‰ (average À1.04‰), a range that is atypical of marine diatom δ 30 Si and that corresponds to the lower limit of reported diatom δ 30 Si values of any age. A binary mixing model (upwelled silicon versus eolian silicon) accounting for silicon isotopic fractionation during DSi uptake by diatoms was constructed. The binary mixing model demonstrates that E. rex dominantly utilized DSi from eolian sources (i.e., Asian dust) with only minor contributions from upwelled seawater sources (i.e., advected from Subantarctic Mode Water, Antarctic Intermediate Water, or North Pacific Intermediate Water). E. rex utilized only ~24% of available DSi, indicating that surface waters of the EPS were eutrophic with respect to silicon during the LGM. Our results suggest that giant diatoms did not always use a buoyancy strategy to obtain nutrients from the deep nutrient pool, thus revising previously proposed models for the formation of E. rex LDMs.
(Paleoceanography. vol. 30, n° 0883-8305, pp. 803-823, 01/07/2015)
UC, RWTH Aachen, MSI, UC Santa Barbara, UC, UCLouvain, EPOC, EPHE, PSL, UB, INSU - CNRS, CNRS
Occurrence of pharmaceutical compounds and pesticides in aquatic systems
This paper deals with the detection and quantification of APIs and other priority substances in the Arade River estuary (Portugal) providing the usefulness of Polar Organic Compound Integrative Samplers (POCIS). Thirteen APIs were detected whose variation was site and time dependent. Caffeine was at the highest concentration (804 ± 209 ng/L) followed by theophylline (184 ± 44 ng/L). Other APIs were analgesic, anticonvulsant, non-steroidal anti-inflammatory drugs, anti-lipidemic, anxiolytic and antidepressants. Twenty pesticides comprising atrazine, diuron, isoproturon, terbutryn and simazine included in the Water Framework Directive priority list were also site and time dependent. Carbendazim occurred at the highest concentration (45 ± 18 ng/L at site 1) but atrazine, diuron, isoproturon and simazine levels were below the Environmental Quality Standards. Although the summer impact was unclear, the results highlighted POCIS suitability for profiling these contaminants. This is to our knowledge the first study concerning APIs and pesticides in this area.
(Marine Pollution Bulletin. vol. 96, n° 0025-326X, pp. 384-400, 01/07/2015)
UAlg, EPOC, EPHE, PSL, UB, INSU - CNRS, CNRS
Etude expérimentale des effets des conditions environnementales (température, oxygène, polluants) sur la survie, le développement et le comportement des stades embryo-larvaires d'esturgeon européen, Acipenser sturio
L'esturgeon européen Acipenser sturio est un poisson migrateur amphihalin qui a connu un fort déclin au cours du 20ème siècle. La dernière population vit dans le bassin Gironde-Garonne-Dordogne (GGD) et sa dernière reproduction connue date de 1994. Les individus relachés lors de repeuplements sont supposés venir se reproduire prochainement. Du fait du changement global et de l'évolution des activités humaines, une meilleure connaissance de la vulnérabilité des jeunes stades de A. sturio vis-à-vis de la température, de la disponibilité en oxygène et des polluants s'est avérée nécessaire. La sensibilité aux conditions oxythermiques actuelles et à venir a été évaluée ainsi que la qualité des sédiments des frayères. Enfin, la sensibilité des jeunes stades de cette espèce à des mélanges de polluants représentatifs du bassin GGD a été également évaluée. Une forte sensibilité des jeunes stades de A. sturio au taux d'oxygène a été mise en évidence. Les fenêtres optimales et critiques de tolérance ont été estimées. La toxicité des sédiments de frayères de Dordogne est globalement supérieur à celle des sédiments de frayères de Garonne. Beauregard et Pessac-sur-Dordogne semblent être respectivement les sites les plus favorables et défavorables aux jeunes stades. La sensibilité de A. sturio aux polluants rencontrés dans le bassin est relativement faible. Les conditions environnementales actuelles du bassin GGD semblent globalement satisfaisantes pour accueillir le développement de jeunes stades de A. sturio. Les données collectées dans cette étude pourront servir pour d'autres programmes de réintroduction de cette espèce.
(pp. 222, 25/06/2015)
UR EABX, IRSTEA, EPOC, EPHE, PSL, UB, INSU - CNRS, CNRS
Velocity estimation of valve movement in oysters for water quality surveillance
The measurements of valve opening activity in a population of oysters under natural environmental conditions are used to estimate the velocity of their valve movement activity. Three different differentiation schemes were used to estimate the velocity, namely an algebraic-based differentiator method, a non-homogeneous higher order sliding mode differentiator and a homogeneous finite-time differentiator. The estimated velocities were then used to compare the performances of these three different differentiators. We demonstrate that this estimated velocity can be used for water quality monitoring as the differentiators can detect very rapid change in valve movements of the oyster population resulting from some external stimulus or common input.
(24/06/2015)
NON-A, Inria, CRIStAL, CNRS, CRIStAL, CNRS, EPOC, EPHE, PSL, UB, INSU - CNRS, CNRS