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National audience; Large part of the existing European legislation on railway noise impact assessment refers to indicators based on long term weighted averages of acoustic intensities (Ldn, Lden, Leq). However, several studies have pointed out that noise event indicators (Lmax, SEL) are more appropriate in order to evaluate annoyance due to intermittent noise sources, such as those due to rail traffic. The computation of these short-term averaged indicators requires the estimation of the instantaneous sound level in the surrounding areas, over a region of several square kilometres. To that purpose we have developed an analytical model, named TR-Noise. TR-Noise adopts a quasi-steady description of outdoor noise propagation to compute cartography of instantaneous sound level and hence the indicators averaged on any timeframe, including short-term. The noise sources are modelled as a weighted sum of monopole and dipole moving at steady velocity along a rail track. The model of sound propagation is based on the ISO/DIS 9613-2 International Standards and takes into account different mechanisms of sound attenuation in the ambient. The model has been used to study the impact assessment of a new railway in a dense populated alpine valley in Italy. Firstly, the model was calibrated by means of a field measurement campaign. Sound level measurements performed close to the rail track have been used to estimate the intensity of the source strength related to different kind of trains. Measurements at larger distances from the rail track allowed us to evaluate the performances of the model and to define the influence of the different factors contributing to sound attenuation. Finally, the model has been used to simulate sound level cartographies due to future scenarios of rail traffic and evaluate their impact on the population.

An assessment of the impact of cruise ship emissions while hotelling in the port of Naples has been studied by means of wind tunnel and computational fluid dynamics (CFD) models. An area of about 1.2 km2 was reproduced at a scale of 1:500 for the wind tunnel experiments. The worst but most emission scenario with three cruise ships emitting at the same time was studied. Wind blows from the south-east with a speed of 3 m/s at funnel height in neutral stability conditions of the atmospheric boundary layer. Two different values of the velocity ratio UR = 1 and UR = 4 (funnel gas velocity/wind speed) were considered. In the experiments, Ethane was used as the tracer gas and the concentration was measured at 35 receptor points inside the urban structure and at different heights. Experimental data show good agreement with those estimated by numerically solving steady Reynolds-Averaged Navier-Stokes (RANS) with the k-ω shear-stress transport (SST) turbulence model. The results were used to analyse the accuracy of the predictions of the model CALifornia Puff (CALPUFF), testing two model options: the building downwash module and the parameterisation of the dispersion coefficients. The CALPUFF results are less accurate than the CFD simulations and show a general tendency to underestimate the experimental data. The optimization process improves the performance of CALPUFF. Finally, a more comprehensive analysis of the effect of a varying UR in the range 0.25–16 was undertaken using numerical models. The research provides useful insights to improve the assessment of the impact of ship emissions in port cities.

OBJECTIVES: Transapical off-pump NeoChord repair is a novel minimally invasive surgical procedure to treat degenerative mitral valve regurgitation. The aim was to evaluate 1-year clinical results of the NeoChord procedure in a consecutive cohort of patients. METHODS: Between February 2013 and July 2016, 213 patients were enrolled in the NeoChord Independent International Registry. All patients presented severe mitral regurgitation due to flail/prolapse of 1 or both leaflets, and they all completed postoperative echocardiographic assessment up to 1 year. We identified the primary end point as composed of procedural success, freedom from mortality, stroke, reintervention, recurrence of severe mitral regurgitation, rehospitalization and decrease of at least 1 New York Heart Association functional class at 1-year follow-up. We also compared outcomes according to the anatomical classification (Type A: isolated central posterior leaflet disease; Type B: posterior multisegment disease; Type C: anterior, bileaflet, paracommissural disease with/without leaflet/annular calcifications). RESULTS: The median age was 68 years (interquartile range 56-77), and the median EuroSCORE II was 1.05% (interquartile range 0.67-1.76). The number of Type A, B and C patients was 82 (38.5%), 98 (46%) and 33 (15.5%), respectively. Procedural success was achieved in 206 (96.7%) patients. At 1-year follow-up, overall survival was 98 ± 1%. Composite end point was achieved in 84 ± 2.5% for the overall population and 94 ± 2.6%, 82.6 ± 3.8% and 63.6 ± 8.4% in Type A, Type B and Type C patients, respectively (P < 0.0001). CONCLUSIONS: These results demonstrate that the NeoChord procedure is safe, effective and reproducible. Clinical and echocardiographic efficacy is maintained up to 1 year with significant differences among the anatomical groups. Specific anatomical selection criteria are necessary to achieve stable results.