137 research outputs found

    IFCP Riemann solver: Application to tsunami modelling using GPUs

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    In this work, we present a simplified two-layer model of Savage-Hutter type to simulate tsunamis generated by landslides (see (Fern´andez et al. 2008)). A layer composed of fluidized granular material is assumed to flow within an upper layer composed of an inviscid fluid (e.g. water). The sediment layer ismodelled by a Savage-Hutter type model where buoyancy effects have been considered. The system is discretized using IFCP finite volume scheme. The first order IFCP scheme was introduced in (Fern´andez et al. 2011) and it is constructed by using a suitable decomposition of a Roe matrix by means of a parabolic viscosity matrix, that captures information of the intermediate fields (Intermediate Field Capturing Parabola). Its extension to high order and two-dimensional domains is straightforward. To conclude, some numerical examples are presente

    Expanded equine cumulus-oocyte complexes exhibit higher meiotic competence and lower glucose consumption than compact cumulus-oocyte complexes

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    Publicado en: Reproduction, Fertility and Development 30(2) 297-306 https://doi.org/10.1071/RD16441 Submitted: 4 November 2016 Accepted: 6 June 2017 Published: 6 July 2017Equine cumulus-oocyte complexes (COCs) are classified as compact (cCOC) or expanded (eCOC) and vary in their meiotic competence. This divergence could be related to different glucose metabolism. To test this hypothesis eCOCs, cCOCs, and expanded or compact mural granulosa cells (EC and CC respectively) were matured in vitro for 30 hours and the maturation rate, glucose metabolism, and expression of genes involved in glucose transport, glycolysis, apoptosis and meiotic competence were determined. Significant differences were found between eCOCs and cCOCs maturation rates (50% vs. 21.7 %; n = 192 and 46 respectively, p < 0.001), glucose consumption (1.8 ± 0.5 vs. 27.9 ± 5.9 nmol/COC; mean ± SEM), pyruvate production (0.1 ± 0.0 vs. 2.4 ± 0.8 nmol/COC; mean ± SEM) and lactate production (4.7 ± 1.3 vs. 64.1 ± 20.6 nmol/COC; mean ± SEM) respectively (p < 0.05). Moreover, similar glucose consumption was observed for EC and CC. Hyaluronan binding protein (TNFAIP6) expression was increased in eCOCs and EC, solute carrier family 2 (facilitated glucose transporter) member 1 (SLC2A1) was increased in eCOCs, while glycolysis-related enzymes and solute carrier family 2 (facilitated glucose transporter) member 3 (SLC2A3) expression did not vary between COCs or mural granulosa cell type. Our data demonstrate that metabolic and genomic differences exist between eCOCs and cCOCs and mural granulosa cells in the horse.This work was financed by AGL2015-66145-R funding from the Spanish Ministry of Economy, Industry and 364 Competitiveness and by AGL2015-73249-JIN(AEI/FEDER/UE) from the "Agencia Estatal de Investigación" 365 (AEI) (Spanish Ministry of Economy, Industry and Competitiveness) and "Fondo Europeo de Desarrollo 366 Regional" (FEDER). Beatriz Macías-García holds a postdoctoral grant "Juan de la Cierva Incorporación"(IJCI-367 2014-19428) from the Spanish Ministry of Economy, Industry and Competitiveness. L.G.-F. (Grant reference: 368 SFRH/BPD/85532/2012) and B. M.-G. (Grant reference: SFRH/BPD/84354/2012) were also partially funded by 369 Fundação para a Ciência e a Tecnologia (Portuguese Ministry for Science, Technology and Higher Education) co370 funded by Programa Operacional Potencial Humano (POPH) financed by European Social Fund (ESF) and 371 Portuguese national funds from Ministry for Science, Technology and Higher Education. The authors thank 372 CECA/ICETA (University of Porto) for funding the abattoir dislocations. The collaboration of Linda Rosa 373 Abattoir is highly appreciated. The authors wish to thank the Laboratory of Applied Physiology (Department of 374 Aquatic Production) of the ICBAS (University of Porto) and especially Mariana Hinzmann for allowing us to use 375 their fluorescence microscope. RNAlater was kindly provided by Dr. Michael Jowers

    Preliminary data on the ovarian histological structures observed in black hakes (M. polli and M. senegalensis) off Mauritania

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    The black hakes, Merluccius polli and M. senegalensis, are target species of a trawl Spanish fleet in Mauritanian waters. M. polli is a deep-water hake while M. senegalensis shows a shallower distribution. Both species are mixed in the landings, although the deeper hake totals a greater fraction (85%) of the catch due to the fishing strategy of the trawl fleet. The female gonads of both hakes were collected during an experimental survey carried out in the Mauritanian EEZ. Mature ovaries were examined from the start of the reproductive season in this area. Ovaries were processed by a standard histological technique. Histological characteristics of ovarian tissues and oocyte stages were studied by light microscopy. The ovaries of black hakes showed various stages of oocyte development from the small sized, chromatin nuclear and perinucleolar oocytes, and the medium sized, cortical alveoli and vitellogenic oocytes. This last stage presents yolk granules occupying the cytoplasm at different levels. In the case of M. senegalensis, the presence of large sized oocytes with early migration of the nucleus to the animal pole, as well as fusion of oil droplets indicate maturation and imminent spawning, thus, indicating an earlier spawning than M. polli. Furthermore, postovulatory follicles observed in M. senegalensis indicate a recent batch spawning episode. This result is concordant with the values of GSI obtained for both species in these waters. The reproductive period extends from October to Mars with a defined peak in December - January for females of both hakes, although the shallower species, M. senegalensis, shows an earlier spawning in this study. Atretic stages were observed, but their incidence was low because the sampling corresponds to the beginning of the spawning period. The species are multiple batch spawners as suggested by their oocyte size frequency distribution in the ovary. The present study is a first approach to ovarian histology of M. polli and M. senegalensis, and intended to provide basic knowledge for further detailed studies on the reproductive biology of these species, essential for an adequate assessment of this stock.Instituto Español de Oceanografía (IEO

    Caracterización de uniones material compuesto-hormigón mediante ensayos de pelado, cortadura, tracción plana y torsión

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    XI CONGRESO NACIONAL DE MATERIALES COMPUESTOS. Celebrado en Móstoles los días 6, 7 y 8 de julio de 2015El presente trabajo se centra en el análisis de diferentes ensayos que permiten determinar la calidad de la unión entre laminados de material compuesto y hormigón. Los ensayos considerados han sido: Pull Off (ensayo a tracción), Shear Torsion (ensayo de torsión), Lap Shear (ensayo de cortadura) y Lap Peeling (ensayo de pelado). La fabricación de las probetas se ha llevado a cabo siguiendo tres procedimientos: por apilado e impregnación manual del material compuesto sobre el hormigón, mediante pegado de laminados de material compuesto prefabricados y mediante impregnación insitu del material compuesto sobre el hormigón a través de técnicas de infusión de resina líquida. Además, dichos ensayos se han realizado sobre probetas de hormigón con dos tratamientos superficiales: amoladora y lija de grano grueso. Tras la realización de los ensayos se ha constatado que predomina la rotura por el hormigón sobre roturas adhesivas o cohesivas, lo que indica una buena adhesión entre éste y el material compuesto, para todos los métodos de fabricación de la unión y tratamientos superficiales del hormigónCentro para el Desarrollo Tecnológico e Industrial (CDTl) lTC-20131020Fondos Europeos de Desarrollo Regional (FEDER) lTC-2013102

    STANDARDIZED CATCH RATES OF ALBACORE (THUNNUS ALALUNGA BONNATERRE, 1788) IN THE SPANISH SURFACE LONGLINE FISHERY IN THE WESTERN MEDITERRANEAN IN THE PERIOD 2009-2019

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    Standardized relative abundance indices of albacore (Thunnus alalunga Bonnaterre, 1788) caught by the Spanish surface longline (LLALB) in the western Mediterranean Sea were estimated for the period 2009-2019. Yearly standardized CPUE were estimated through Generalized Linear Mixed Effects Models (GLMM) under a negative binomial error distribution assumption. The main factors in the standardization analysis were year and season (quarter). The index shows an increasing trend from the beginning of the series (2009) to a maximum in 2011; following a decrease up to 2013, and a relatively stable trend fluctuating around a level three and a half times lower compared to the maximum abundance for the period 2013-2019.En prens

    North Atlantic oscillation affects the physical condition of migrating bullet tuna Auxis rochei (Risso, 1810) from the Western Mediterranean Sea

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    Climate oscillations exert direct control over the environment in which they occur and may influence the physical condition of migratory marine species, such as tuna, as reported by several authors. The main aim of thisstudywastoexploretheassociationbetweenthepotentialeffectsoftheNorthAtlanticOscillation(NAO)on thefitness condition of bullet tuna (Auxis rochei) migrating to the Spanish Mediterranean Sea. A total of 2357 length-weight pairs of data obtained from individuals collected on the Spanish Mediterranean coast were analysed. A non-parametric Spearman test was used to investigate correlations between the atmospheric oscillation indexes and two physical condition indexes. The results suggest that, in general, positive phases of the NAO index improve the physical condition offish migrating to spawning grounds in the Mediterranean Sea. These results could be explained by changes in the dominant winds, which could favour pre-spawning migration, and by nutrients availability, which guarantees their recovery after the spawning period.En prens

    Standardized catch rates for Mediterranean swordfish (Xiphias gladius Linnaeus, 1758) from the Spanish longline fishery. 1988-2017.

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    Standardized relative abundance indices for swordfish (Xiphias gladius Linnaeus, 1758) caught by the Spanish surface longline in the western Mediterranean Sea were estimated for the period 1988-2017. Standardized CPUEs were estimated through a General Linear Mixed Modeling (GLMM) approach under a negative binomial (NB) error distribution assumption. The main factors in the standardization analysis were fishing area and time of the year (quarter). The standardized index showed notable annual fluctuations without any definite trend for the period under study

    Historical and ecological drivers of the spatial pattern of Chondrichthyes species richness in the Mediterranean Sea

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    Chondrichthyes, which include Elasmobranchii (sharks and batoids) and Holocephali (chimaeras), are a relatively small group in the Mediterranean Sea (89 species) playing a key role in the ecosystems where they are found. At present, many species of this group are threatened as a result of anthropogenic effects, including fishing activity. Knowledge of the spatial distribution of these species is of great importance to understand their ecological role and for the efficient management of their populations, particularly if affected by fisheries. This study aims to analyze the spatial patterns of the distribution of Chondrichthyes species richness in the Mediterranean Sea. Information provided by the studied countries was used to model geographical and ecological variables affecting the Chondrichthyes species richness. The species were distributed in 16 Operational Geographical Units (OGUs), derived from the Geographical Sub-Areas (GSA) adopted by the General Fisheries Commission of the Mediterranean Sea (GFCM). Regression analyses with the species richness as a target variable were adjusted with a set of environmental and geographical variables, being the model that links richness of Chondrichthyes species with distance to the Strait of Gibraltar and number of taxonomic families of bony fishes the one that best explains it. This suggests that both historical and ecological factors affect the current distribution of Chondrichthyes within the Mediterranean Sea.Postprin

    Biological aspects of little tunny Euthynnus alletteratus from Spanish and Portuguese waters.

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    This study provides information on some biological aspects of Euthynnus alletteratus from the western Mediterranean (Spanish coast) and in the Atlantic Ocean (south of Iberian Peninsula). A total of 1266 individuals were measured between 2003 and 2017. The L-W relationship was calculated with W equal to 0.01242 FL3.058 . Histological analysis of the ovaries and the monthly variation of the gonadosomatic index for both sexes suggested that the spawning season for Euthynnus alletteratus in the western Mediterranean Sea takes place from June to August. The lengths at first maturity (L50) were estimated to be 50.1 cm and 43.4 cm FL for female and male, respectively. Age at first maturity (A50) was calculated
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