313 research outputs found

    The rare case of positive FDG-positron emission tomography for giant cavernous hemangioma of the liver

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    Hemangioma is the most common benign liver tumor and the second most common liver tumor after metastases. Large hemangiomas are often heterogeneous. When they exceed 4 cm in diameter, they are termed giant hemangiomas. These giant hemangiomas often present heterogeneous patterns. These heterogeneous appearances are shown because of intratumoral changes due to several degenerative phenomena. PET/CT is reported to be useful for the differentiation of benign from malignant liver lesions. We report the case of a large hepatic hemangioma characterized by high FDG uptake

    Coexistence of supersymmetric and supersymmetry-breaking states in spherical spin-glasses

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    The structure of states of the perturbed p-spin spherical spin-glass is analyzed. At low enough free energy metastable states have a supersymmetric structure, while at higher free energies the supersymmetry is broken. The transition between the supersymmetric and the supersymmetry-breaking phase is triggered by a change in the stability of states

    Evaluating meteorological climate model inputs to improve coastal hydrodynamic studies

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    Abstract. This work compares meteorological results from different regional climate model (RCM) implementations in the Mediterranean area, with a focus on the northern Adriatic Sea. The need to use these datasets as atmospheric forcings (wind and atmospheric pressure fields) for coastal hydrodynamic models to assess future changes in the coastal hydrodynamics, is the basis of the presented analysis. It would allow the assessment of uncertainties due to atmospheric forcings in providing coastal current, surge and wave climate changes from future implementations of hydrodynamic models. Two regional climate models, with different spatial resolutions, downscaled from two different global climate models (whose atmospheric components are, respectively, ECHAM4 and ECHAM5), were considered. In particular, the RCM delivered wind and atmospheric pressure fields were compared with measurements at four stations along the Italian Adriatic coast. The analyses were conducted using a past control period, 1960–1990, and the A1B IPCC future scenario (2070–2100). The chosen scenario corresponds to a world of very rapid economic and demographic growth that peaks in mid-century, with a rapid introduction of new efficient technologies, which balance fossil and non-fossil resources (IPCC, 2007). Consideration is given to the accuracy of each model at reproducing the basic statistics and the trends. The role of models' spatial resolution in reproducing global and local scale meteorological processes is also discussed. The Adriatic Sea climate is affected by the orography that produces a strengthening of north-eastern katabatic winds like bora. Therefore, spatial model resolution, both for orography and for a better resolution of coastline (Cavaleri et al., 2010), is one of the important factors in providing more realistic wind forcings for future hydrodynamic models implementations. However, also the characteristics in RCM setup and parameterization can explain differences between the datasets. The analysis from an ensemble of model implementation would provide more robust indications on climatic wind and atmospheric pressure variations. The scenario-control comparison shows a general increase in the mean atmospheric pressure values while a decrease in mean wind speed and in extreme wind events is seen, particularly for the datasets with higher spatial resolution

    SINTA - SImulations of climate chaNge in the mediTerranean Area - Final scientific report

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    This SINTA Project establish a scientific cooperation between the Italian Scientific Institution INGV (National Institute of Geophysics and Volcanology) and the Serbian Scientific Institutions such as the Republic HydroMeteorological Service (RHMSS) and the University of Belgrade (UB). INGV contributes the global models, University of Belgrade and RHMSS contribute their expertise on regional models, parameterization ofphysical processes and numerical schemes. In particular, the main objectives of this Project are: 1) Perform a set of global simulations with a Global Climate Model (GCM) available at INGV; 2) Perform a set of regional simulations with the UB Regional Climate Model (RCM) forced by boundary conditions from the GCM simulations; 3) Test the convection parameterization developed at UB in the INGV global model; 4) Training and visit exchanges of Serbian scientists in Italy

    Seasonal prediction of the boreal winter stratosphere

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    The predictability of the Northern Hemisphere stratosphere and its underlying dynamics are investigated in five state-of-the-art seasonal prediction systems from the Copernicus Climate Change Service (C3S) multi-model database. Special attention is devoted to the connection between the stratospheric polar vortex (SPV) and lower-stratosphere wave activity (LSWA). We find that in winter (December to February) dynamical forecasts initialised on the first of November are considerably more skilful than empirical forecasts based on October anomalies. Moreover, the coupling of the SPV with mid-latitude LSWA (i.e., meridional eddy heat flux) is generally well reproduced by the forecast systems, allowing for the identification of a robust link between the predictability of wave activity above the tropopause and the SPV skill. Our results highlight the importance of November-to-February LSWA, in particular in the Eurasian sector, for forecasts of the winter stratosphere. Finally, the role of potential sources of seasonal stratospheric predictability is considered: we find that the C3S multi-model overestimates the stratospheric response to El Niño–Southern Oscillation (ENSO) and underestimates the influence of the Quasi–Biennial Oscillation (QBO)

    Socio-demographic characteristics and cognitive performance in oldest old subjects asking for driving license renewal

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    Background: No papers have examined the relationship between socio-demographic characteristics and cognitive performance in oldest old subjects (i.e, > = 80 years old) asking for driving license renewal. We hypothesize that, even in this highly functioning population, age, sex, and education influence cognitive performance, expressed as total or single domain (raw) test scores. This research question allows to describe, identify, and preserve independence of subjects still able to drive safely. Methods: We examined cross-sectionally a cohort of > = 80 years old subjects (at enrollment) asking for driving license renewal in the Milan area, Italy, 2011\u20132017. The analysis was restricted to 3378 first and 863 second visits where individual\u2019s cognitive performance was evaluated. According to the study protocol, the Mini Mental State Examination (MMSE) test was administered at the first visit for driving license renewal and the Montreal Cognitive Assessment (MoCA) test at the second visit, following an additional renewal request. Ordinary least squares regression models were fitted at either time points. In each model, we included age, sex, and education as independent variables, whereas the dependent variable was total or single domain score for either test. In total, we fitted 15 regression models to assess our research hypothesis. Results: The median subject in our sample reached the maximum scores on domains targeting operational and tactical abilities implied in safe driving, but had sub-optimal scores in the long-term memory domain included among the strategic abilities. In multiple models, being > = 87 (versus 80- < 86 years old) significantly decreased the mean total and memory scores of MMSE, but not those of the MoCA. Females (versus males) had significantly higher mean total and long-term memory scores of either tests, but not other domains. Mean total and single domain scores increased for increasing education levels for either tests, with increments for high school graduates being ~ 2 of those with (at most) a junior high school diploma.Conclusions: Sex and education, as well as age to a lesser extent, predict cognitive functioning in our oldest old population, thus confirming that concepts like cognitive reserve and successful ageing are valuable constructs in the identification of older subjects still able to drive

    Coupled ocean-atmosphere modeling and predictions

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    Key aspects of the current state of the ability of global and regional climate models to represent dynamical processes and precipitation variations are summarized. Interannual, decadal, and globalwarming timescales, wherein the influence of the oceans is relevant and the potential for predictability is highest, are emphasized. Oceanic influences on climate occur throughout the ocean and extend over land to affect many types of climate variations, including monsoons, the El Niño Southern Oscillation, decadal oscillations, and the response to greenhouse gas emissions. The fundamental ideas of coupling between the ocean-atmosphere-land system are explained for these modes in both global and regional contexts. Global coupled climate models are needed to represent and understand the complicated processes involved and allow us to make predictions over land and sea. Regional coupled climate models are needed to enhance our interpretation of the fine-scale response. The mechanisms by which large-scale, low-frequency variations can influence shorter timescale variations and drive regionalscale effects are also discussed. In this light of these processes, the prospects for practical climate predictability are also presented.AJMwas supported by theNSFEarth System Modeling Program (OCE1419306) and the NOAA Climate Variability and Prediction Program (NA14OAR4310276). HS thanks the Office of Naval Research for support under N00014-15-1-2588. LPP was supported by “Advanced Studies in Medium and High Latitudes Oceanography” (CAPES 23038.004304/2014-28) and “National Institute of Science andTechnology of the Cryosphere” (CNPq/PROANTAR704222/2009). VM was supported by NOAA grant NA12OAR4310078. TGJ was supported by the U. S. Naval Research Laboratory 6.2 project “Fresh Water Balance in the Coupled Ocean-Atmosphere System” (BE-435-040-62435N-6777) YHT was supported by the MOST grant 106-2111-M-002-001, Taiwan
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