722 research outputs found

    Evaporating waterbody effects in a simplified urban neighbourhood: A RANS analysis

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    The incorporation of nature-based solutions comprising green and blue infrastructure is often touted as a way to cool cities and enhance pollutant removal. However, there is little agreement between different methodologies to measure the effect of any single intervention. Here, we present 3D steady RANS simulations to investigate the influence of waterbody on in-canyon flow structure, temperature (T*) and water vapour (!*) distribution in a simplified urban neighbourhood. A novel solver that captures evaporation effects is developed and validated against wind tunnel experiments. Simulations are performed under neutral atmospheric conditions for forced -and mixed-convection cases and different air-water temperature differences, indicative of either daytime or night-time conditions. Results under forced convection show minimal impact on the flow structure, whilst T* and !* effects are distributed primarily over and around the water surface. However, the mixed-convection case shows that a cooler waterbody weakens the principal vortex in the open square, whilst T* and !* effects reach further upwind and are more widely distributed in the spanwise direction. A warmer waterbody is shown to disrupt the skimming flow structure, indicating a possible heat and pollutant removal mechanism from around the waterbody and also downwind canyons

    Sub-Nyquist Field Trial Using Time Frequency Packed DP-QPSK Super-Channel Within Fixed ITU-T Grid

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    Sub-Nyquist time frequency packing technique was demonstrated for the first time in a super channel field trial transmission over long-haul distances. The technique allows a limited spectral occupancy even with low order modulation formats. The transmission was successfully performed on a deployed Australian link between Sydney and Melbourne which included 995 km of uncompensated SMF with coexistent traffic. 40 and 100 Gb/s co-propagating channels were transmitted together with the super-channel in a 50 GHz ITU-T grid without additional penalty. The super-channel consisted of eight sub-channels with low-level modulation format, i.e. DP-QPSK, guaranteeing better OSNR robustness and reduced complexity with respect to higher order formats. At the receiver side, coherent detection was used together with iterative maximum-a-posteriori (MAP) detection and decoding. A 975 Gb/s DP-QPSK super-channel was successfully transmitted between Sydney and Melbourne within four 50GHz WSS channels (200 GHz). A maximum potential SE of 5.58 bit/s/Hz was achieved with an OSNR=15.8 dB, comparable to the OSNR of the installed 100 Gb/s channels. The system reliability was proven through long term measurements. In addition, by closing the link in a loop back configuration, a potential SE*d product of 9254 bit/s/Hz*km was achieved

    From building regulations and local health rules to the new local building codes. A national survey in Italy on the prescriptive and performance requirements for a new performance approach

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    BACKGROUND: World Health Organization has highlighted the need to strengthen the relationship between health and built environment factors, such as inappropriate housing conditions. Building Regulations and Local Health Rules provide safety and building hygiene in construction practices. Currently the Italian Government is giving rise to a Building Regulation Type and the paper aims to verify the present contents of recent innovative Local Health Rules and Building Regulations of several Italian municipalities for supporting the performance approach of the future Building Regulations including hygienic issues. METHODS: The analysis examines both Building Regulations and Local Health Rules of a sample of about 550 cities, analysing some specific fields of interest: urban field, outdoor issues, housing features, housing restrictions, and qualitative aspects. RESULTS: The analysis focuses on some specific aspects defining the general data reported in Building Regulations and Local Health Rules, in particular around surfaces, heights, lighting and aeration ratio, basements and semi-basements, gas radon, building greenery, etc. CONCLUSION: The investigation permitted to have a wide vision on the present State of the Art in order to highlight some innovative aspects and design approaches of Building Regulations and Local Health Rules. New perspectives in the new regulations should have a performance approach, starting also from the recent SARS-CoV-2 pandemic

    Multislice computed tomography SYNTAX score for coronary artery disease evaluation prior to transcatheter aortic valve implantation

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    Background: Coronary computed tomography angiography (CCTA) is a useful tool for the evaluation of coronary anatomy prior to both surgical and transcatheter aortic valve implantation (TAVI). Multislice Computed Tomography (MSCT) SYNTAX score (SXscore) strongly correlates with the traditional angiographic SXscore, and the latter has proven to predict cardiovascular events in patients with coronary artery disease (CAD) referred to TAVI. Purpose: The aim of the study is to evaluate the feasibility and accuracy of the calculation of MSCT SXscore in TAVI patients, compared to the gold standard angiographic SXscore. Materials and methods: We evaluated 65 patients eligible for TAVI who underwent both CCTA and invasive coronary angiography (ICA) prior to valve replacement. CCTA was compared to ICA in terms of sensitivity, specificity, and positive and negative predictive values. CCTA performance was evaluated at 3 levels: patient level, vessellevel and segmentlevel. MSCT SXscore was calculated, when possible (i.e. only in fullyevaluable scans), and compared to the angiographic SXscore. Results: Overall CCTA diagnostic performance was good, with high sensitivity and negative predictive values (97.2% and 96.0%, respectively) and good agreement with ICA (k=0.81). As expected, specificity and positive predictive values were lower (82.8% and 87.5%, respectively). At vessellevel, the circumflex artery (CA) was more often misdiagnosed than the other arteries. We were able to calculate MSCT SXscore in 50/65 scans (76.9%). The correlation between MSCT and angiographic SXscore was excellent (Pearson's R=0.965, P<0.001). Conclusions: MSCT SXscore emerges as an interesting tool with strong agreement with angiographic SXscore, providing a noninvasive ambulatory alternative to assess CAD severity in TAVI patients

    A proposal of hygienic and sanitary standards for the new Building Code in Italy

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    The traditional emphasis of Public Health on the type and quality of housing today merges with other wider determinants of health such as: the neighbourhood, the community and the "place" where a home is located, but also the policies that make access to a healthy home within everyone's reach. At the neighbourhood scale, context-related aspects heavily influence the internal quality and real usability of the buildings themselves, with particular reference to factors such as the quality of the site, the relationship between the building and the context, the presence and quality of the greenery and open spaces surrounding the building, as well as all measures that make it possible to reduce the building's impact on the environment, to protect it against environmental pollution, and to manage the building in an integrated manner for maintenance purposes. Creating healthy living environments means referring to the different dimensions mentioned above, and this not only requires the attention of Public Health operators, but also implies an integration of vision and objectives among various professional skills and competences that puts health at the center of all policies. This proposal, which starts from the analysis of existing local hygiene regulations and scientific literature, aims to take stock of a number of areas considered fundamental for the assessment of building hygiene aspects, with particular reference to the eco-sustainability of buildings and adaptation to climate change. The aspects identified can be considered as a starting point for the preparation of integrated building and hygiene regulations based on documented effective practices for the protection of Public Health

    Comparing the safety and effectiveness of five leading new-generation devices for transcatheter aortic valve implantation: Twelve-month results from the RISPEVA study

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    Objectives. The management of severe aortic stenosis has been revolutionized by the introduction of transcatheter aortic valve implantation (TAVI), especially in patients at intermediate, high, or prohibitive surgical risk. There is uncertainty, however, regarding the comparative effectiveness and safety of contemporary TAVI devices. Methods. We queried detailed data from the ongoing national Italian TAVI registry and compared baseline features, procedural details, and 12-month outcomes of Acurate Neo (Boston Scientific), Evolut Pro/R (Medtronic), Lotus (Boston Scientific), Portico (Abbott Vascular), and Sapien/ Sapien S3 Ultra (Edward Lifesciences) transcatheter aortic valves. Several endpoints were collected and appraised, including the composite of death, stroke, myocardial infarction (MI), major bleeding, major vascular complication, surgical aortic valve replacement and transcatheter aortic valve reimplantation, which were deemed major adverse events (MAEs). Results. A total of 1976 patients were included, with 234 treated with Acurate, 703 with Evolut, 151 with Lotus, 347 with Portico, and 541 with Sapien. Twelve-month events were not significantly different among the 5 devices, including death (P=.29) and MAE (P=.21), with the notable exception of major vascular complications, which were more common with Acurate and Sapien (P<.001) and permanent pacemaker implantation, which was more frequent with Lotus and Evolut (P<.001). Differences in MAE were more pronounced in women and subjects with prior cardiac surgery, with the lowest event rates in the Evolut group. Propensity-score adjusted analysis suggested that Acurate, Evolut, Portico, and Sapien were all associated with similarly favorable results, whereas adverse events were more evident with Lotus (P<.05). Conclusion. Leading current-generation TAVI devices offer similarly favorable results at mid-term follow-up

    The development of parental monitoring during adolescence : A meta-analysis

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    As adolescents grow up, one of the important developmental tasks is to individuate themselves and to become more autonomous from parents. This requires a realignment of the parent-adolescent communication. The current meta-analytic study aims at identifying developmental changes in parent-adolescent communication, conceptualized within the parental monitoring framework, as entailing parental solicitation, control and knowledge, and adolescent’s disclosure and secrecy. Thirty-one longitudinal studies published between 2000 and 2015 were identified and included in the current meta-analysis. Informants, age at assessment and study duration were tested as moderators. Results showed a low to medium normative decline in parental control (Cohen’s d = −.395, 95% CI [−.541, −.249]), knowledge (d = −.245,95% CI [−.331, −.160] and adolescence disclosure (d = −.147, 95% CI [−.204, −.090]), and an increase in adolescent’s secrecy (d = .194, CI [031, .356]). Parental solicitation decreased based on parents’ (d = −.242, 95% CI[−.376, −.109]) but not on adolescents’ reports (d = .038, 95% CI[−.099, .175]). Another significant moderator was the duration of the study, with studies longer than 2 years being able to detect a more pronounced change in parental control than studies lasting less than 2 years (≤2 years, d = −.139 vs. duration > 2 years, d = −.581). Limitations of the current knowledge and new directions of studies are discussed.Peer reviewe

    are drug eluting stents superior to bare metal stents in patients with unprotected non bifurcational left main disease insights from a multicentre registry

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    Aims To compare long-term clinical outcome following drug-eluting stents (DES) or bare-metal stents (BMS) implantation on lesions located at the ostium or the shaft of the left main in a large real-world population. The advent of DES decreased the risk of unprotected left main coronary artery (ULMCA) restenosis when compared with BMS, but it is unclear if this advantage continues when non-bifurcational lesions are considered. Methods and results The GISE-SICI registry is a retrospective, observational multicentre registry promoted by the Italian Society of Invasive Cardiology in which 19 high-volume participating centres enrolled 1453 consecutive patients who underwent percutaneous coronary intervention on ULMCA between January 2002 and December 2006. From the registry, a total of 479 consecutive patients with ostial and shaft lesions who underwent DES ( n = 334) or BMS ( n = 145) implantation were analysed with extensive multivariable and propensity score adjustments. At 3-year follow-up, risk-adjusted survival rates were higher in patients treated with DES than in those treated with BMS. The adjusted hazard ratio (HR) for the risk of mortality after DES implantation relative to BMS implantation was 0.37 (95% CI: 0.15–0.96, P = 0.04). The adjusted HR for the risk of cardiac mortality was 0.31 (95% CI: 0.09–1.04, P = 0.06). The adjusted 3-year rates of target lesion revascularization (TLR) were not significantly lower in the DES group than in the BMS group ( P = 0.60). Conclusion In a large population of patients with lesions located at the ostium or the shaft of the left main in a real-world setting, DES were associated with favourable clinical outcomes when compared with BMS, although there was no evidence of a significant reduction in TLR with DES vs. BMS
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