465 research outputs found

    Nuevo mĂ©todo de preparaciĂłn de soforosa y kojibiosa a partir de 1,6-anhidro-β-D-glucopiranosa

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    A new method for the preparation of the dissaccharides sophorose and kojibiose by theatment of the 1,6-anhydro-β-D-glucopyranose in DMFHCl 0,03 N under mild conditions is reported.Se describe un nuevo método para la preparación de los disacáridos soforosa y kojibiosa por tratamiento en condiciones suaves de 1,6-anhidro-β-D-glucopiranosa en DMF-HCl 0,03 N

    Oligomerización dé aldohexosas en DMF-HCl. Estudio del mecanismo

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    On the basis of the obtained data for acid catalysed oligomerization reactions of D-glucose, D-galactose, D-manose and L-rhamnose in DMFHCl, mechanistic schemes are proposed.Basándose en los datos obtenidos en reacciones de oligomerización catalizadas por ácidos de D-glucosa, D-galactosa, D-manosa y L-rhamnosa en DMF-HGl se proponen esquemas mecanísticos para cada caso

    Modelling the hydrodynamic conditions associated with Dinophysis blooms in Galicia (NW Spain)

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    The northwestern Iberian coast (Galician RĂ­as and shelf) is frequently affected by toxic harmful algal blooms (HABs) (mainly Dinophysis spp.), leading to lengthy harvesting closures in a region where aquaculture has a strong socioeconomic impact. The project ASIMUTH (http://www.asimuth.eu) aimed to develop forecasting capabilities to warn of impending HABs along the European Atlantic coast. Simulations with the ROMS model (hydrodynamical and ecological simulations complemented with Lagrangian particle tracking simulations) of the Galician coastal circulation have been performed in the framework of the ASIMUTH project to characterize and forecast oceanographic conditions before and during HAB periods. In this work, we present the Galician ASIMUTH forecast system and demonstrate its skill in predicting HAB transport and its usefulness to provide assessment for the management of the areas affected by toxic outbreaks. Experience gained during DSP events in 2005 and 2013 is shown. We also describe the Galician pilot HAB bulletins, aimed at distributing forecasts of HAB events that might induce closures of harvesting areas or, when the areas are already closed, at giving information on forthcoming oceanographic conditions that could favour or hamper the opening of an area. Our results show that the model forecasts and the bulletins can provide early warning of the risk of Dinophysis spp. events and the risk of closures linked to the presence of DSP toxins above regulatory levels in harvesting areas.VersiĂłn del editor3,083

    Numerical simulations with the ASIMUTH forecast system for understanding and forecasting HAB events in Galicia (NW Spain)

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    Simulations with the model ROMS (hydrodynamical and ecological simulations complemented with Lagrangian particle-tracking simulations) have been performed in the framework of the project ASIMUTH (http://www.asimuth.eu) which aims to develop forecasting capabilities to warn of impending harmful algal blooms (HABs) along the European Atlantic coast. In this contribution, we will report on the skill of the ASIMUTH forecast system in predicting transport of HABs and in assessing the area affected by HABs in the upwelling-influenced Galician rias (NW Spain) with the experience gained in years 2013 and 2014.ASIMUTH FP7/26186

    Outer Regions of the Milky Way

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    With the start of the Gaia era, the time has come to address the major challenge of deriving the star formation history and evolution of the disk of our MilkyWay. Here we review our present knowledge of the outer regions of the Milky Way disk population. Its stellar content, its structure and its dynamical and chemical evolution are summarized, focussing on our lack of understanding both from an observational and a theoretical viewpoint. We describe the unprecedented data that Gaia and the upcoming ground-based spectroscopic surveys will provide in the next decade. More in detail, we quantify the expect accuracy in position, velocity and astrophysical parameters of some of the key tracers of the stellar populations in the outer Galactic disk. Some insights on the future capability of these surveys to answer crucial and fundamental issues are discussed, such as the mechanisms driving the spiral arms and the warp formation. Our Galaxy, theMilkyWay, is our cosmological laboratory for understanding the process of formation and evolution of disk galaxies. What we learn in the next decades will be naturally transferred to the extragalactic domain.Comment: 22 pages, 10 figures, Invited review, Book chapter in "Outskirts of Galaxies", Eds. J. H. Knapen, J. C. Lee and A. Gil de Paz, Astrophysics and Space Science Library, Springer, in pres

    Towards a HAB forecast service in the Galician region

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    We will present the recent developments of our forecasting capabilities to warn of impending harmful algal blooms (HABs) in Galicia, where aquaculture has a strong socio-economic impact. A HAB warning service for monitoring agencies and the aquaculture industry has been developed as a demonstration of a Copernicus marine downstream service coupled to the MyOcean service. In this contribution, we describe the Galician ASIMUTH forecast system and demonstrate its skill in predicting HAB transport and its usefulness to provide assessment for the management of the areas affected by toxic outbreaks. We also describe the Galician pilot HAB bulletins, aimed at distributing forecasts of HAB events that might induce closures of harvesting areas or, when the areas are already closed, at giving information on forthcoming oceanographic conditions that could favour or hamper the opening of an area. Our results show that the model forecasts and the bulletins can provide early warning of the risk of Dinophysis spp. events and the risk of closures linked to the presence of toxins above regulatory levels in harvesting areas.Instituto Español de Oceanografí

    MastectomĂ­a contralateral profilĂĄctica con reconstrucciĂłn inmediata en pacientes con cĂĄncer de mama unilateral sin mutaciĂłn germinal en BRCA1/2

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    IntroducciĂłn No existe un consenso sobre las indicaciones de mastectomĂ­a contralateral en pacientes diagnosticadas de cĂĄncer de mama unilateral sin mutaciĂłn germinal en BRCA1/2. Estudios previos han identificado algunos factores que pueden influir en la toma de la decisiĂłn dependientes del tumor, como el tamaño o histologĂ­a, de la paciente, como la edad, y de la cirugĂ­a como la posibilidad de realizar una reconstrucciĂłn inmediata o la experiencia del cirujano. MĂ©todos Estudio retrospectivo de una cohorte de 176 pacientes diagnosticadas de CM entre 2010 y 2016 a las que se les realizĂł cirugĂ­a mamaria. Se ha analizado la asociaciĂłn de caracterĂ­sticas del tumor y de la paciente con la toma de decisiĂłn de realizar mastectomĂ­a contralateral (MC) o no-MC. Asimismo, se han analizado los datos relacionados con la cirugĂ­a y la recurrencia por grupos mediante la curva de incidencia acumulada y el test de Gray. Resultados El nĂșmero de MC se ha incrementado en nuestro centro. No hemos encontrado diferencias significativas en el desarrollo de complicaciones posquirĂșrgicas entre los 2 grupos de pacientes, pero sĂ­ en la estancia hospitalaria, siendo superior para MC. TambiĂ©n hemos observado diferencias entre ambas cohortes en edad y tipo de tumor, siendo la MC mĂĄs frecuente en aquellas pacientes mĂĄs jĂłvenes y subtipo luminal A. Hemos hallado diferencias en la incidencia acumulada de recidiva entre ambos subgrupos (p = 0, 034). Conclusiones En nuestra cohorte la MC se realiza mĂĄs frecuentemente en pacientes mĂĄs jĂłvenes y con cĂĄncer de mama luminal A. Introduction: There is no consensus on the indications for contralateral mastectomy (CM) in patients diagnosed with unilateral breast cancer without germline BRCA1/2 mutations. Prior studies have identified some factors that could influence decision-making. These factors include tumoural size and histological type; patient-related factors, such as age; and surgical factors such as the possibility of immediate reconstruction and the surgeon''s experience. Methods: Retrospective study of a cohort of 176 patients diagnosed with breast cancer between 2010 and 2016 who underwent breast surgery. We analysed the association between tumoural and patient-related characteristics with the decision to perform CM or not. We also analysed data related to surgery and recurrence by groups by using the cumulative incidence curve and the Gray test. Results: The number of CM has increased in our centre. We found no significant differences in the occurrence of post-surgical complications between the two patient groups but length of hospital stay was higher in CM. We also found differences between the two cohorts in age and tumoural type, with CM being more frequent in younger patients and those with luminal A subtype. Differences were found in the cumulative incidence of recurrence between subgroups (p = 0.034). Conclusions: In our cohort, CM was more frequent in younger patients and in those with luminal A breast cancer

    Search for direct production of charginos and neutralinos in events with three leptons and missing transverse momentum in √s = 7 TeV pp collisions with the ATLAS detector

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    A search for the direct production of charginos and neutralinos in final states with three electrons or muons and missing transverse momentum is presented. The analysis is based on 4.7 fb−1 of proton–proton collision data delivered by the Large Hadron Collider and recorded with the ATLAS detector. Observations are consistent with Standard Model expectations in three signal regions that are either depleted or enriched in Z-boson decays. Upper limits at 95% confidence level are set in R-parity conserving phenomenological minimal supersymmetric models and in simplified models, significantly extending previous results

    Jet size dependence of single jet suppression in lead-lead collisions at sqrt(s(NN)) = 2.76 TeV with the ATLAS detector at the LHC

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    Measurements of inclusive jet suppression in heavy ion collisions at the LHC provide direct sensitivity to the physics of jet quenching. In a sample of lead-lead collisions at sqrt(s) = 2.76 TeV corresponding to an integrated luminosity of approximately 7 inverse microbarns, ATLAS has measured jets with a calorimeter over the pseudorapidity interval |eta| < 2.1 and over the transverse momentum range 38 < pT < 210 GeV. Jets were reconstructed using the anti-kt algorithm with values for the distance parameter that determines the nominal jet radius of R = 0.2, 0.3, 0.4 and 0.5. The centrality dependence of the jet yield is characterized by the jet "central-to-peripheral ratio," Rcp. Jet production is found to be suppressed by approximately a factor of two in the 10% most central collisions relative to peripheral collisions. Rcp varies smoothly with centrality as characterized by the number of participating nucleons. The observed suppression is only weakly dependent on jet radius and transverse momentum. These results provide the first direct measurement of inclusive jet suppression in heavy ion collisions and complement previous measurements of dijet transverse energy imbalance at the LHC.Comment: 15 pages plus author list (30 pages total), 8 figures, 2 tables, submitted to Physics Letters B. All figures including auxiliary figures are available at http://atlas.web.cern.ch/Atlas/GROUPS/PHYSICS/PAPERS/HION-2011-02

    Patterns of ash (Fraxinus excelsior L.) colonization in mountain grasslands: the importance of management practices

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    International audienceWoody colonization of grasslands is often associated with changes in abiotic or biotic conditions or a combination of both. Widely used as fodder and litter in the past traditional agro-pastoral system, ash (Fraxinus excelsior L.) has now become a colonizing species of mountain grasslands in the French Pyrenees. Its present distribution is dependent on past human activities and it is locally controlled by propagule pressure and abiotic conditions. However, even when all favourable conditions are met, all the potentially colonizable grasslands are not invaded. We hypothesize that management practices should play a crucial role in the control of ash colonization. From empirical field surveys we have compared the botanical composition of a set of grasslands (present and former) differing in management practices and level of ash colonization. We have displayed a kind of successional gradient positively linked to both ash cover and height but not to the age of trees. We have tested the relationships between ash presence in grassland and management types i.e. cutting and/or grazing, management intensity and some grassland communities' features i.e. total and local specific richness and species heterogeneity. Mixed use (cutting and grazing) is negatively linked to ash presence in grassland whereas grazing alone positively. Mixed use and high grazing intensity are directly preventing ash seedlings establishment, when low grazing intensity is allowing ash seedlings establishment indirectly through herbaceous vegetation neglected by livestock. Our results show the existence of a limit between grasslands with and without established ashes corresponding to a threshold in the intensity of use. Under this threshold, when ash is established, the colonization process seems to become irreversible. Ash possesses the ability of compensatory growth and therefore under a high grazing intensity develops a subterranean vegetative reproduction. However the question remains at which stage of seedling development and grazing intensity these strategies could occur
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