Tropospheric pathways of the late-winter ENSO teleconnection to Europe

The late-winter signal associated with the El Niño-Southern Oscillation (ENSO) over the European continent is unsettled. Two main anomalous patterns of sea-level pressure (SLP) can be identified: a “wave-like” pattern with two opposite-signed anomalies over Europe, and a pattern showing a single anomaly (“semi-isolated”). In this work, potential paths of the tropospheric ENSO teleconnection to Europe and their role in favoring a more wave-like or semi-isolated pattern are explored. Outputs from historical runs of two versions of the MPI-ESM coupled model, which simulate these two types of patterns, are examined. A novel ray-tracing approach that accounts for zonal asymmetries in the background flow is used to test potential propagation paths in these simulations and in observations; three source regions are considered: the tropical Pacific, the North America/North Atlantic, and the tropical Atlantic. The semi-isolated pattern is suggested to be related to the well-known Rossby wave train emanating from the tropical Pacific, either via a split over northern North America or via reflection due to inhomogeneities in the background flow. The wave-like pattern, in turn, appears to be related to a secondary wave train emerging from the tropical Atlantic. The competition between these two pathways contributes to determining the actual surface response.B.M. and J.G.-S. were supported by the “Contratos Predoctorales para la Formación de Doctores” (BES-2016-076431) and “Ramón y Cajal” (RYC-2016-21181) programmes, respectively. Tercio Ambrizzi was supported by the National Institute of Science and Technology for Climate Change Phase 2 under CNPq Grant 465501/2014-1, 301397/2019-8; FAPESP Grants 2014/50848-9 and 2017/09659-6. This study also received funding from the Spanish ATLANTE project (PID2019-110234RB-C21). We acknowledge the World Climate research Programme’s Working Group on Coupled Modelling, which is responsible for CMIP. Technical support at BSC (Computational Earth Sciences group) is sincerely acknowledged. We also thank the two anonymous reviewers for their valuable insights.Peer ReviewedPostprint (published version

Tropospheric pathways of the late-winter ENSO teleconnection to Europe

The late-winter signal associated with the El Niño-Southern Oscillation (ENSO) over the European continent is unsettled. Two main anomalous patterns of sea-level pressure (SLP) can be identified: a "wave-like" pattern with two opposite-signed anomalies over Europe, and a pattern showing a single anomaly ("semi-isolated"). In this work, potential paths of the tropospheric ENSO teleconnection to Europe and their role in favoring a more wave-like or semi-isolated pattern are explored. Outputs from historical runs of two versions of the MPI-ESM coupled model, which simulate these two types of patterns, are examined. A novel ray-tracing approach that accounts for zonal asymmetries in the background flow is used to test potential propagation paths in these simulations and in observations; three source regions are considered: the tropical Pacific, the North America/North Atlantic, and the tropical Atlantic. The semi-isolated pattern is suggested to be related to the well-known Rossby wave train emanating from the tropical Pacific, either via a split over northern North America or via reflection due to inhomogeneities in the background flow. The wave-like pattern, in turn, appears to be related to a secondary wave train emerging from the tropical Atlantic. The competition between these two pathways contributes to determining the actual surface response

The use of a combined bipedicled axial perforator based fasciocutaneous flap for the treatment of a traumatic diabetic foot wound: a case report

The axial and perforator vascularised fasciocutaneous flaps are reliable and effective treatment methods for covering lower limb post-traumatic, septic, Charcot, and diabetic foot wounds. The authors describe the unique utilisation of a hybrid flap as an axial-perforator flap combination for the treatment of a traumatic diabetic foot wound

Experimental Aspects for CeO2 Nanoparticles Synthesis and Characterization

In recent years, cerium oxide (CeO2, or ceria) became a versatile nanostructured material because of its unique properties derived from the low dimensionality and high surface area. It was also extensively studied due to its practical performances in many scientific and industrial applications, such as fuel cells, luminescent materials, gas sensors, insulators, white LEDs, etc. In this paper, the research focused on the synthesis and characterization of cerium oxide powder manufactured by the co-precipitation method, using inorganic cerium salt (Ce(NO3)3) and the precipitating agent (NaOH). In order to optimize the CeO2 particles synthesis process, the parameters of the process were monitored to obtain the quantitative precipitate and to optimize the heat treatment. The precursors type and concentration used, reaction temperature and time, the pH of reaction medium and order of the precipitating agent addition are the main factors influencing the particle size and morphology of cerium oxide nanoparticles. The physico-chemical properties of the cerium oxide nanoparticles were determined by Fourier transform infrared spectroscopy (FTIR), X-ray diffraction (XRD), and scanning electron microscopy (SEM), energy dispersive X-ray analysis (EDX). The FTIR spectrum of the CeO2 particles calcinated at 550 °C, in normal atmosphere, exhibits a strong band at 482 cm-1 corresponding to Ce-O stretching vibration. The XRD pattern confirmed the crystalline nature of the CeO2 nanoparticles with a cubic structure and average crystallite size around 15 nm. Moreover, EDX analysis confirms the presence of the Ce and O atoms corresponding to the theoretical formula. The morphology and microstructure were studied using SEM analysis