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Aortic valve regurgitation is a not negligible complication of prolonged support with continuous-flow left ventricular assist device (LVAD) and is associated with recurrence of heart failure and reduced survival. Transcatheter aortic valve implantation has been described as a feasible option in this setting, usually with self-expanding prosthesis. Giving the absence of valvular calcification, a proper prosthesis oversizing should be guaranteed in order to achieve sufficient sealing and avoid prosthesis migration or paravalvular leak. Current self-expanding prosthesis may be too small to fit aortic annulus anatomies without calcification and with the need of significant oversize. We report the first case of 32 mm balloon expandable Myval prosthesis implantation in a patient with LVAD-related aortic regurgitation. Large balloon-expandable prosthesis can be considered when a significant oversize is needed.

New generation of district heating had introduced the concept of smart thermal grids, consisting in the bidirectional heat exchange between network and final users. In this context, users substations represent key points for the optimal integration between district heating networks and distributed generators. In this paper several schemes for smart users substations will be presented and the actions required to convert existing substations will be evaluated through a technical analysis.

In this study, the behaviour of a small-scale hybrid energy system is predicted by means of a developed calculation model. In more detail, the experimental setup consists of photovoltaic panels, batteries and an electrolyzer; the mathematical sub-models for each device are provided. These sub-models have been validated by means of experimental data, recorded during laboratory tests. The results show that each sub-model reproduces very well the experimental data and then the whole system model can be applied to identify the optimal management strategy of a solar-to-hydrogen micro-scale system.

The aim of this study was to investigate the safety and efficacy of coronary protection by preventive coronary wiring and stenting across the coronary ostia in patients at high risk for coronary obstruction after transcatheter aortic valve replacement (TAVR).Coronary obstruction following TAVR is a life-threatening complication with high procedural and short-term mortality.Data were collected retrospectively from a multicenter international registry between April 2011 and February 2019.Among 236 patients undergoing coronary protection with preventive coronary wiring, 143 had eventually stents implanted across the coronary ostia after valve deployment. At 3-year follow-up, rates of cardiac death were 7.8% in patients receiving stents and 15.7% in those not receiving stents (adjusted hazard ratio: 0.42; 95% confidence interval: 0.14 to 1.28; p = 0.13). There were 2 definite stent thromboses (0.9%) in patients receiving stents, both occurring after TAVR in "valve-in-valve" procedures. In patients not receiving stents, there were 4 delayed coronary occlusions (DCOs) (4.3%), occurring from 5 min to 6 h after wire removal. Three cases occurred in valve-in-valve procedures and 1 in a native aortic valve procedure. Distance between the virtual transcatheter valve and the protected coronary ostia 4 mm was present in 75.0% of patients with DCO compared with 30.4% of patients without DCO (p = 0.19).In patients undergoing TAVR at high risk for coronary obstruction, preventive stent implantation across the coronary ostia is associated with good mid-term survival rates and low rates of stent thrombosis. Patients undergoing coronary protection with wire only have a considerable risk for DCO.

L’articolo descrive il sistema micro-ORC a banco prova nei laboratori del DIN dell’Università di Bologna. Vengono presentati i layout dell’impianto in analisi e descritti brevemente i componenti principali. Sono quindi riportati gli strumenti implementati per la misura delle grandezze termo-fluidodinamiche che caratterizzano il ciclo, nonché il software di acquisizione ed elaborazione dei dati. Infine vengono mostrate le relazioni utilizzate per il calcolo dei principali indici di prestazione.

the proposed tutorial would like to highlight the potential of polygeneration in the sustainable energy development, as well as associated challenges. In details, the first attempt of the tutorial is to introduce the concept of a polygeneration grid and its main characteristics. Once defined the framework, the role of renewable energies and associated issues, with particular interest to non-programmable sources (such as solar and wind) will be discussed. To accommodate the presence of non-programmable renewables and their intermittent and unreliable nature, storage devices and energy carriers are fundamentals. Both state-of-art and innovative storage technologies will be sort throughout the tutorial. As innovative and promising way to convert electrical power into gaseous energy carriers, the Power-to-Gas (P2G) system will be discussed. In particular, the P2G process links the power grid with the gas grid by converting surplus power into a grid compatible gas via a two-step process: hydrogen production by water electrolysis and its conversion with an external CO2 source to CH4 via methanation. The synthetic fuel generated can be used as a substitute for natural gas or other fossil fuels in a diverse range of applications (e.g. in the industry, mobility and heating sectors and also for electricity generation). Focusing on thermal aspect, Smart District Heating concept will also play an important role by developing future smart energy integrating systems. In the current energy scenario, indeed, it is important to consider a possible integration between networks and distributed generation systems – i.e to realize a bidirectional energy flux at the utilities, replying the concept of electrical smart grid in the thermal energy field. To this purpose, several thermal energy distributed generation systems, such as solar thermal panels or micro-Combined Heat and Power (micro-CHP) generators, can be considered. In this context, the users substations structure and the network management play a fundamental role, as will be discussed during the tutorial. Finally, another central aspect that characterizes multi-input/multi-output energy grids, that will be stressed and discussed during the tutorial, is the optimal load allocation. Indeed, the coupling of various generation technologies, operating with different performance both at design and off-design conditions, requires a proper optimal management strategy since different mix of production can meet the user demand (electrical, thermal and cooling). The operational management has to follow a strategy aiming at some objective like maximization of renewable energy share, minimization of operational cost, minimization of environmental emission etc. Thus, focusing on this issue, an introduction on optimal load allocation techniques (such as genetic algorithm, mixed integer linear programming etc.) is presented.

Objectives: To compare the long-term clinical outcomes of paclitaxel drug-coated-balloons (DCB) and everolimus-eluting-stents (EES) following the treatment of de novo small vessel coronary artery disease. Background: It is currently unclear whether treatment of de novo small vessel coronary disease with DCB is comparable to second generation drug-eluting stents, which are the current standard of care. Methods: The present study enrolled 90 patients with small vessel coronary disease from the DCB treatment arm of the BELLO (Balloon Elution and Late Loss Optimization) trial and 2,000 patients treated with EES at the San Raffaele Scientific Institute. Propensity score matching was performed to adjust for differences in baseline clinical and angiographic characteristics, yielding a total of 181 patients: 90 patients with 94 lesions receiving DCB and 91 patients with 94 lesions receiving EES. Major adverse cardiac events (MACE) were defined as the composite of cardiac death, recurrent non-fatal myocardial infarction, and target vessel revascularization. Results: After propensity score matching, baseline clinical and angiographic characteristics were similar between the two groups. The cumulative MACE rate at 1-year was 12.2% with DCB and 15.4% with EES (P = 0.538). Patients in the DCB group had similar TLR rates as compared to EES over the same interval (4.4% vs. 5.6%; P = 0.720). There were no cases of definite or probable stent or vessel thrombosis. Conclusions: The use of paclitaxel-DCB appears to be associated with similar clinical outcomes when compared to second-generation-EES in small coronary artery disease. The findings of this study should be confirmed with larger prospective randomized studies with longer follow-up. © 2017 Wiley Periodicals, Inc.

Recenti vicende umane e giuridiche hanno portato in primo piano il tema del testamento biologico e del rapporto tra l’uomo, la malattia e la morte. L’interrogativo sulla morte è connesso con quello della vita umana che viene considerata ora come la semplice sopravvivenza dell’organismo biologico, ora come un’esperienza che racchiude aspetti emotivi, affettivi e relazionali. Le discipline psicologiche possono aiutare a riflettere sul rapporto della società contemporanea con la malattia e con la morte, sui riti che accompagnano tali esperienze, sui processi decisionali che sottostanno al testamento biologico. Nell’epoca contemporanea la medicina si accosta al morente con l’idea di vincere la morte e ritardare il suo avvento, invece di tendere alla coniugazione degli aspetti tecnici con quelli umani e relazionali. Il testamento biologico può essere considerato come uno strumento che permette di recuperare la consapevolezza sulle tematiche connesse alla morte, di implementare la relazione terapeutica e di migliorare la qualità della vita nell’ultima fase dell’esistenza umana.

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We propose an intelligent sensor system based on a new sensing methodology, relying also on 3D map reconstruction techniques, for computing with high precision, in real-time and without human intervention the parameters needed for stream-flow computation: water levels, morphology of the streams of all potentially flooded areas by each controlled stream. The collected data will be continuously transmitted, through a communication infrastructure, to software agents designed to compute the stream-flow and to quantify the spatial distribution of flood risk for each controlled watershed. The computed risks, together with other data coming from other sources (barometric sensors, camera operators of public organizations, emergency agencies, private citizens), will be analyzed by a diagnostic decision system implementing a risk-alert scheduling strategy. This system will be able to diagnose the health state of the controlled environment and to define specialized alarm levels for each potentially interested area that will be used to alert all citizens (ubiquity) locally present (alerting locality).© 2014 Published by Elsevier B.V. Open access under CC BY-NC-ND license

Het Nieuwe Werken is al sinds begin jaren negent ig in opkomst en raakt steeds meer ingeburgerd, zowel bij private als bij publieke organisaties. Dit artikel gaat in op de belangrijkste kenmerken en drijfveren, ervaringen van gebruikers, vereiste gebouweigenschappen en instrumenten ter ondersteuning van de besluitvorming.

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In this paper we propose an algorithm for automatic transformation of a graph into a 3D Virtual World and its Euclidean map, using the rectangular dualization technique. The nodes of the initial graph are transformed into rooms, the connecting arcs between nodes determine which rooms have to be placed next to each other and define the positions of the doors connecting those rooms. The proposed algorithm is general enough to be used for automatic generation of 3D Virtual Worlds representation of any planar graph, however, our research is particulary focused on the automatic generation of 3D Electronic Institutions from the Performative Structure graph. Copyright © 2007, Australian Computer Society, Inc.

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The Indiana MAS project, funded by the Italian Ministry of Education, University and Research "Futuro in Ricerca 2010" program, aims at providing a framework for the digital protection and conservation of rock art natural and cultural heritage sites, by storing, organizing and presenting information about them in such a way to encourage scientific research and to raise the interest and sensibility towards them from the common people. The project involves two research units, namely Genova (Dipartimento di Informatica, Bioingegneria, Robotica e Ingegneria dei Sistemi) and Salerno (Dipartimento di Matematica e Informatica), for a period of 36 months, starting from march 8th, 2012. The technologies adopted in the project range from agents to ontologies, as requested by the complex nature of the platform, where each module is devoted to a specific task: sketch and symbol recognition, semantic interpretation of complex visual scenes, multi-language text understanding, storing, classification and indexing of multimedia and heterogeneous digital objects. All of them should cooperate and coordinate in order to enable higher level components to reason on them and to detect relationships among different digital objects, hence providing new hypothesis based on such relationships.

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Severe aortic stenosis (AS) is often associated with ascending aorta dilation (AAD). AAD is amenable to surgical correction combined with aortic valve replacement. Transcatheter aortic valve implantation (TAVI) might represent a valid therapeutic option in these patients when AAD correction Is not indicated. The aim of the present study is to evaluate the impact of concomitant AAD on early and mid-term outcomes after TAVI for symptomatic severe AS.

Understanding the flow of information in Deep Neural Networks (DNNs) is a challenging problem that has gain increasing attention over the last few years. While several methods have been proposed to explain network predictions, there have been only a few attempts to compare them from a theoretical perspective. What is more, no exhaustive empirical comparison has been performed in the past. In this work, we analyze four gradient-based attribution methods and formally prove conditions of equivalence and approximation between them. By reformulating two of these methods, we construct a unified framework which enables a direct comparison, as well as an easier implementation. Finally, we propose a novel evaluation metric, called Sensitivity-n and test the gradient-based attribution methods alongside with a simple perturbation-based attribution method on several datasets in the domains of image and text classification, using various network architectures., Comment: ICLR 2018

Background The aim of the study was to demonstrate the safety and effectiveness of a suture-mediated vascular closure device to perform hemostasis after an axillary artery access during endovascular procedures on the aortic valve, the aorta and its side branches. Methods A physician-initiated, international, multicenter, retrospective registry was designed to evaluate the success rate (VARC-2 reporting standards) of percutaneous transaxillary access closure with a suture-mediated closure device. Secondary end points were minor access vascular complications, transient peripheral nerve injury, stroke, and influence on periprocedural outcomes of puncture technique. Results Three hundred thirty-one patients (median age, 76 years; 69.2% males) in 11 centers received a percutaneous transaxillary access during endovascular cardiac (n = 166) or vascular (n = 165) procedures. The closure success rate was 84.6%, with 5 open conversions (1.5%), 45 adjunctive endovascular procedures (13.6%), and 1 nerve injury (0.3%). Secondary closure success was obtained in 325 patients (98%) after 7 bare stenting, 37 covered stenting, and 1 thrombin injection. Introducer sheaths 16F or larger (odds ratio, 3.70; 95% confidence interval, 1.22-11.42) and balloon-assisted hemostasis (odds ratio, 4.45; 95% confidence interval, 1.27-15.68) were associated with closure failure. A threshold of five percutaneous axillary accesses was associated with decreased rates of open conversion, but not with increased primary closure success. Primary closure success was 90.3% in the 175 patients with sheaths smaller than 16F, performed after the first 5 procedures in each center. Temporary nerve injury and stroke were observed in 2% and 4% of patients, respectively. Conclusions Percutaneous transaxillary aortic procedures, in selected patients, can be performed with low rates of open conversion. The need for additional endovascular bailout procedures is not negligible when introducers sheaths 16F or larger are required.