20 research outputs found

    Disentangling diverse responses to climate change among global marine ecosystem models

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    Climate change is warming the ocean and impacting lower trophic level (LTL) organisms. Marine ecosystem models can provide estimates of how these changes will propagate to larger animals and impact societal services such as fisheries, but at present these estimates vary widely. A better understanding of what drives this inter-model variation will improve our ability to project fisheries and other ecosystem services into the future, while also helping to identify uncertainties in process understanding. Here, we explore the mechanisms that underlie the diversity of responses to changes in temperature and LTLs in eight global marine ecosystem models from the Fisheries and Marine Ecosystem Model Intercomparison Project (FishMIP). Temperature and LTL impacts on total consumer biomass and ecosystem structure (defined as the relative change of small and large organism biomass) were isolated using a comparative experimental protocol. Total model biomass varied between −35% to +3% in response to warming, and -17% to +15% in response to LTL changes. There was little consensus about the spatial redistribution of biomass or changes in the balance between small and large organisms (ecosystem structure) in response to warming, an LTL impacts on total consumer biomass varied depending on the choice of LTL forcing terms. Overall, climate change impacts on consumer biomass and ecosystem structure are well approximated by the sum of temperature and LTL impacts, indicating an absence of nonlinear interaction between the models’ drivers. Our results highlight a lack of theoretical clarity about how to represent fundamental ecological mechanisms, most importantly how temperature impacts scale from individual to ecosystem level, and the need to better understand the two-way coupling between LTL organisms and consumers. We finish by identifying future research needs to strengthen global marine ecosystem modelling and improve projections of climate change impacts

    Feasibility studies of time-like proton electromagnetic form factors at PANDA at FAIR

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    Simulation results for future measurements of electromagnetic proton form factors at \PANDA (FAIR) within the PandaRoot software framework are reported. The statistical precision with which the proton form factors can be determined is estimated. The signal channel pˉpe+e\bar p p \to e^+ e^- is studied on the basis of two different but consistent procedures. The suppression of the main background channel, i.e.\textit{i.e.} pˉpπ+π\bar p p \to \pi^+ \pi^-, is studied. Furthermore, the background versus signal efficiency, statistical and systematical uncertainties on the extracted proton form factors are evaluated using two different procedures. The results are consistent with those of a previous simulation study using an older, simplified framework. However, a slightly better precision is achieved in the PandaRoot study in a large range of momentum transfer, assuming the nominal beam conditions and detector performance

    Study of doubly strange systems using stored antiprotons

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    Bound nuclear systems with two units of strangeness are still poorly known despite their importance for many strong interaction phenomena. Stored antiprotons beams in the GeV range represent an unparalleled factory for various hyperon-antihyperon pairs. Their outstanding large production probability in antiproton collisions will open the floodgates for a series of new studies of systems which contain two or even more units of strangeness at the P‾ANDA experiment at FAIR. For the first time, high resolution γ-spectroscopy of doubly strange ΛΛ-hypernuclei will be performed, thus complementing measurements of ground state decays of ΛΛ-hypernuclei at J-PARC or possible decays of particle unstable hypernuclei in heavy ion reactions. High resolution spectroscopy of multistrange Ξ−-atoms will be feasible and even the production of Ω−-atoms will be within reach. The latter might open the door to the |S|=3 world in strangeness nuclear physics, by the study of the hadronic Ω−-nucleus interaction. For the first time it will be possible to study the behavior of Ξ‾+ in nuclear systems under well controlled conditions

    Informe nº 1: Impacte de la pandèmia en l’atenció al part de les dones amb resultat positiu de COVID-19

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    El mes de març de l’any 2020 la pandèmia global provocada per la COVID-19 va generar una crisi sanitària i de cures a nivell internacional. A Catalunya, com a molts altres indrets de l’Estat espanyol, d’Europa i del món, els serveis sanitaris es van veure desbordats i van entrar en risc de col·lapse, no només per donar resposta als estralls causats per la nova malaltia sinó per atendre altres situacions, com ara l’atenció a les dones embarassades abans, durant i després del part. En aquest context, les mesures adoptades en els serveis de salut per fer front a l’escenari d’emergència van resultar en alteracions importants dels processos d’atenció a la maternitat tal i com es venien realitzant fins el moment i, fins i tot, algunes veus van denunciar que els drets sexuals i reproductius de les dones en situació d’embaràs, part o postpart s’estaven veient subordinats a les exigències de la gestió de la pandèmia i, en algunes ocasions, vulnerats. Partint de l’interès en entendre la mesura i la manera en què es va veure afectada l’atenció sanitària a les dones en un moment tan fonamental de les seves vides, des del Grup de Recerca Societats, Polítiques i Comunitats Inclusives (SopCI) i la Càtedra UNESCO Dones, Desenvolupament i Cultures de la Universitat de Vic-Universitat Central de Catalunya vam impulsar el projecte de recerca Drets sexuals i reproductius en temps de pandèmia: maternitat i COVID-19 a Catalunya. El projecte va rebre inicialment el finançament del Ministeri d’Igualtat (Secretaria d’Estat d’Igualtat i contra la Violència de Gènere/Pacto de Estado contra la Violencia de Género). Posteriorment també ha rebut suport de la Secretaria d’Universitats i Recerca del Departament d’Empresa i Coneixement de la Generalitat de Catalunya (2017SGR0657). L’estudi va estar aprovat pel Comitè d’Ètica per a la Recerca de la Universitat de Vic-Universitat Central de Catalunya. Més enllà de les publicacions i altres resultats científics que es puguin derivar del projecte, des de l’equip d’investigació considerem que les dades que se n’han generat són de gran rellevància per, en primer lloc, visibilitzar situacions, no sempre positives, que milers de dones a Catalunya van haver de viure en un moment de les seves vides de màxima vulnerabilitat i necessitat de cura i acompanyament. D’altra banda, també ens sembla important publicar els principals resultats de la investigació en aquest format divulgatiu d’informe breu per fer-los fer accessibles a diferents públics.2017SGR065

    Structural and thermal analyses of zinc and lactose in homeopathic triturated systems

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    BACKGROUND: A series of different experimental approaches was applied in Zincum metallicum (Zinc met.) samples and lactose controls. Experiments were designed to elucidate the effect of zinc trituration and dynamization on physicochemical properties of homeopathic formulations, using lactose as excipient. METHODS: Zinc met. potencies (Zinc met 1-3c) were triturated and dynamized using lactose as excipient, according to Brazilian Homeopathic Pharmacopoeia. Lactose samples (LAC 1-3c) were also prepared following the same protocol and used as controls. The samples were analyzed structurally by Atomic Absorption Spectroscopy (AAS), X-ray Diffraction (XRD), Transmission Electron Microscopy (TEM) with Energy Dispersive X-ray Spectroscopy (EDX) and Scanning Electron Microscopy (SEM), and thermodynamically by Thermogravimetry (TG) and Differential Scanning Calorimetry (DSC). RESULTS: AAS analysis detected 97.0 % of zinc in the raw material, 0.75 % (Zinc met 1c) and 0.02% (Zinc met 2c). XRD analysis showed that inter-atomic crystalline spacing of lactose was not modified by dynamization. Amorphous and crystalline lactose spheres and particles, respectively, were observed by TEM in all samples, with mean size from 200 to 800 nm. EDX obtained with TEM identified zinc presence throughout the amorphous matter but individualized zinc particles were not observed. SEM images obtained from dynamized samples (LAC 1c and Zinc met 1c) with electron backscattering could not identify zinc metal grains. The dynamization process induced Derivatives of Thermal Gravimetric (DTg) peak modification, which was previously centered near 158\ub0C to lactose, to a range from 140 to 170\ub0C, suggesting the dynamization process modifies the temperature range of water aggregation. Thermal phenomena were analyzed and visualized by Analysis of Variance (ANOVA) and Principal Component Analysis (PCA) statistics. Both indicated that fusion enthalpy of dynamized samples (DynLAC 1-3c; DynZn 1-3c) increased 30.68 J/g in comparison to non-dynamized lactose (LAC; p < 0.05). CONCLUSIONS: Our results suggested no structural changes due to the trituration and dynamization process. However, TG and DSC analyses permit the differentiation of dynamized and non-dynamized groups, suggesting the dynamization process induced a significant increase in the degradation heat. These results call for further calorimetric studies with other homeopathic dilutions and other methodologies, to better understand the dynamics of these systems

    Technical Design Report for the Panda Forward Spectrometer Calorimeter

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    This document is devoted to the electromagnetic calorimeter of the Forward Spectrometer and describes the design considerations, the technical layout, the expected performance, and the production readiness

    Technical Design Report for the Panda Forward Spectrometer Calorimeter

    No full text
    This document is devoted to the electromagnetic calorimeter of the Forward Spectrometer and describes the design considerations, the technical layout, the expected performance, and the production readiness

    Centrality dependence of the charged-particle multiplicity density at mid-rapidity in Pb-Pb collisions at sNN\sqrt{s_{NN}} = 2.76 TeV

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    The centrality dependence of the charged-particle multiplicity density at mid-rapidity in Pb-Pb collisions at sNN\sqrt{s_{NN}} = 2.76 TeV is presented. The charged-particle density normalized per participating nucleon pair increases by about a factor 2 from peripheral (70-80%) to central (0-5%) collisions. The centrality dependence is found to be similar to that observed at lower collision energies. The data are compared with models based on different mechanisms for particle production in nuclear collisions.The centrality dependence of the charged-particle multiplicity density at mid-rapidity in Pb-Pb collisions at sNN\sqrt{s_{\rm NN}} = 2.76 TeV is presented. The charged-particle density normalized per participating nucleon pair increases by about a factor 2 from peripheral (70-80%) to central (0-5%) collisions. The centrality dependence is found to be similar to that observed at lower collision energies. The data are compared with models based on different mechanisms for particle production in nuclear collisions
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