2,744 research outputs found

    Non-annular, hemispheric signature of the winter North Atlantic Oscillation

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    Sensitivity experiments with an atmospheric general circulation model (AGCM) without a proper stratosphere are performed to locally force a North Atlantic oscillation (NAO)-like response in order to analyse the tropospheric dynamics involved in its hemispheric extent. Results show that the circulation anomalies are not confined to the North Atlantic basin not even within the first 10 days of integration, where the atmospheric response propagates downstream into the westerly jets. At this linear stage, transient-eddy activity dominates the emerging, regional NAO- like pattern while zonal-eddy coupling may add on top of the wave energy propagation. Later at the quasi-equilibrium nonlinear stage, the atmospheric response emphasizes a wavenumber-5 structure embedded in the westerly jets, associated with transient-eddy feedback upon the Atlantic and Pacific storm-tracks. This AGCM waveguided structure rightly projects on the observational NAO-related circumglobal pattern, providing evidence of its non-annular character in the troposphere. These findings support the view on the importance of the circumglobal waveguide pattern on the development of NAO-related anomalies at hemispheric level. It could help to settle a consensus view of the Arctic Oscillation, which has been elusive so far.This work has been partially supported by the CANON Foundation in Europe (Grant 2011-062). JG-S was partially supported by the H2020-funded MSCA-IF-EF DPETNA project (GA No. 655339). Thanks to Mashiro Watanabe and Masato Mori (AORI, University of Tokyo) for useful discussions in the early stages of this study. Thanks also to Francisco J. Doblas-Reyes (BSC, Spain) and Pablo Zurita-Gotor (UCM, Spain) for their help during the review process. Technical support at BSC (Computational Earth Sciences group) is sincerely acknowledged. The authors are grateful to the anonymous reviewers for their encouragement and helpful suggestions.Peer ReviewedPostprint (author's final draft

    The Sustainable Management of Metals: An Analysis of Global Research

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    The objective of this study was to analyze research trends in the field of sustainable management of metals on a global level between 1993 and 2017. To do so, a bibliometric analysis was carried out on a total of 6967 articles. The results revealed the growing interest in this research field, particularly over the last five year-period during which 63% of all articles were published. The three journals in which most articles had been published were the Journal of Cleaner Production, ACS Sustainable Chemistry and Engineering, and Chemsuschem. The countries that published the most articles were China, the United States, India, Germany, and the United Kingdom. A sizeable network of collaboration has been established between countries for the joint publication of studies. The main lines of research have been focused on metal decontamination in water and soil, waste management oriented towards reuse and recycling, and the innovation of processes for cleaner and more efficient production. The results revealed the need for comprehensive studies that integrate different disciplines within the same analytical framework, and to promote research that contributes to the different dimensions of sustainability (environmental, economic, and social)

    Influence of Reynolds number on theoretical models for trailing vortices

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    We conduct direct numerical simulations for a NACA0012 airfoil at Reynolds numbers (Re) ranging from 300 to 7000 to determine the wake behavior behind this wing profile. We characterize the structure of the wing-tip vortex, finding a reasonable agreement with experimental results at Re=7000. In addition, we model the trailing vortex theoretically, thus obtaining the parameters for Batchelor’s and Moore and Saffman’s models. We compare the results of the best fitting for the axial vorticity and the azimuthal velocity, finding only small discrepancies. The main contribution of this research work is to study the evolution of these theoretical parameters as function of the Reynolds number. We observe that the wake becomes unstable at Re ≈1200, in agreement with previous results. These instabilities in the wake behind the wing produce a change in the trend of theoretical parameters (keywords: vortex dynamics, trailing vortices, theoretical models).Universidad de Málaga. Campus de Excelencia Internacional Andalucía Tech

    Bullous pemphigoid and dipeptidyl peptidase-4 inhibitors: The importance of the pharmacotherapeutic history

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    A 97-year-old man with a history of type II diabetes mellitus was treated with oral antidiabetic agents. He went to the emergency department after the appearance of blister-like itchy lesions on the abdomen and extremities since 2 months. The examination revealed eczematous lesions on the back, abdomen and extremities along with tense blisters on an erythematous base and serous content (figure 1A). In the blood test carried out, 285?mg/dL glucose and 7.1% eosinophilia stood out, with no associated leucocytosis or other relevant findings. Positive glycosuria (+++) was observed in urinalysis without other alterations. A skin biopsy was performed for histological and immunofluorescence studies that confirmed the diagnosis of bullous pemphigoid (figure 1B–D). Given the poor control of autoimmune blistering disease, possible triggers were looked for and linagliptin intake could be associated with the appearance of skin lesions 1?month earlier. ..

    Incidence, risk factors, and evolution of venous thromboembolic events in patients diagnosed with pancreatic carcinoma and treated with chemotherapy on an outpatient basis.

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    Background Pancreatic carcinoma is one of the tumors associated with a higher risk for thromboembolic events, with incidence rates ranging from 5% to 41% in previous retrospective series. Patients and methods We conducted a retrospective study in eleven Spanish hospitals that included 666 patients diagnosed with pancreatic carcinoma (any stage) between 2008 and 2011 and treated with chemotherapy. The main objective was to evaluate the incidence of venous thromboembolic events (VTE) in this population, as well as potential risk factors for thrombosis. The impact of VTE on mortality was also assessed. Results With a median follow-up of 9.3 months, the incidence of VTE was 22.1%; 52% were diagnosed incidentally. Our study was unable to confirm the ability of the Khorana score to discriminate between patients in the intermediate or high risk category for thrombosis. The presence of VTE proved to be an independent prognostic factor associated with increased risk of death (HR 2.39, 95% CI 1.96–2.92). Symptomatic events correlated with higher mortality than asymptomatic events (HR 1.72; 95% CI, 1.21–2.45; p = 0.002), but incidental VTE, including visceral vein thrombosis (VVT), negatively affected survival compared to patients without VTE. Subjects who developed VTE within the first 3 months of diagnosis of pancreatic carcinoma had lower survival rates than those with VTE after 3 months (HR 1.92, 95% CI 1.30–2.84; p<0.001). Conclusions Pancreatic carcinoma is associated with a high incidence of VTE, which, when present, correlates with worse survival, even when thrombosis is incidental. Early onset VTE has a particularly negative impact.post-print1290 K

    Present and future of the OTELO project

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    OTELO is an emission-line object survey carried out with the red tunable filter of the instrument OSIRIS at the GTC, whose aim is to become the deepest emission-line object survey to date. With 100% of the data of the first pointing finally obtained in June 2014, we present here some aspects of the processing of the data and the very first results of the OTELO survey. We also explain the next steps to be followed in the near future.Comment: Oral contribution presented in the XI Scientific Meeting of the Spanish Astronomical Society held on September 8-12, in Teruel, Spain (7 pages, 2 figures, 1 table). To appear in Highlights of Spanish Astrophysics VIII, Proceedings of the XI Scientific Meeting of the Spanish Astronomical Society. Eds. A. J. Cenarro, F. Figueras, C. Hern\'andez-Monteagudo, J. Trujillo, L. Valdiviels

    Room-temperature ferromagnetism in the mixtures of the TiO₂ and Co₃O₄ powders

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    We report here the observation of ferromagnetism (FM) at 300 K in mixtures of TiO₂ and Co₃O₄ powders despite the antiferromagnetic and diamagnetic characters of both oxides, respectively. The ferromagnetic behavior is found in the early stages of reaction and only for TiO₂ in anatase structure; no FM is found for identical samples prepared with rutile-TiOÂČ. Optical spectroscopy and x-ray absorption spectra confirm a surface reduction of octahedral Co^(+3) -> Co^(+2) in the mixtures which is in the origin of the observed magnetism
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