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Coronary obstruction is an uncommon and severe complication after a transcatheter aortic valve replacement (TAVR), that occurs during the procedure in the vast majority of patients. In the present case even in the absence of classic risk factors, an acute coronary syndrome occurred one day after TAVR. Selective angiography revealed a severe left main ostium obstruction by the bulky native leaflet calcification. This is the first case of delayed presentation of coronary obstruction with a transfemoral balloon-expandable valve using the Inovare bioprosthesis (Braile Biomedica, Brazil). In addition, after drug-eluting stent placement in the left main coronary, intravascular ultrasound revealed severe stent underexpansion, so that a second layer of a bare-metal stent and high-pressure balloon post-dilatation was necessary to improve the final result. The patient was discharged after 7 days, and at the 6-month follow-up remained asymptomatic. < Learning objective: This case illustrates an unusual cause of an acute coronary syndrome 24 h after a transcatheter aortic valve replacement. This is the first report of this severe complication with delayed presentation following the balloon-expandable Inovare bioprosthesis. Even in the absence of classic risk factors this complication may occur, and percutaneous coronary intervention is feasible in the vast majority of cases, often requiring various percutaneous techniques and intravascular image to improve outcomes.> [ABSTRACT FROM AUTHOR]

Abstract Fiber-Reinforced Polymer (FRP) represents one of the most diffuse and effective strengthening technique for retrofitting columns in existing buildings when presenting insufficient mechanical properties. In fact, the confinement effect provided by wraps with high-tensile strength and stiffness induces significant enhancement of the mechanical behaviour. In this paper experimental results of axial compression tests on both un-confined and FRP-confined prismatic yellow tuff masonry columns are presented. In particular, two types of masonry arrangements, regular and irregular, were reproduced in order to investigate the effectiveness of the confinement on column typologies widely used in the past in Southern Italy and Mediterranean basin. The performed experimental tests allowed to obtain the constitutive axial and transversal stress-strain laws and to evaluate the improvement of the mechanical behaviour, in terms of strength and ductility, due to FRP confinement. The results have highlighted a significant difference in the shape of the constitutive law for confined masonry with respect to the one of confined concrete. Contrary to FRP confined concrete members, in the case of confined masonry members specific theoretical constitutive model has been not yet developed. To this aim, in this paper the various stress-strain laws developed for FRP-confined concrete elements has been applied to masonry elements too and a comparative analyses between experimental and theoretical results has been carried out. [ABSTRACT FROM AUTHOR]

Structural safety assessment of urbanised areas exposed to seismic risk is a complex task and can be approached at different scales. Fragility functions are the most effective tool to perform an estimation of the structural risk, since they describe the exceeding probability of the limit state of interest given a level of ground shaking. The formulation of a fragility function is based on the selection of an Intensity Measure of the ground shaking, commonly represented by peak-ground or spectral parameters or by macroseismic intensity grades. In the present paper, a novel approach to estimate the seismic vulnerability at a large scale of urbanised areas is presented. The scenario earthquakes are selected according to the current formulation of the seismic hazard disaggregation provided by National and International codes, i.e. through the disaggregation in terms of magnitude (M), epicentral distance (R) and number of standard deviation from the median ground motion (ε). To this aim, a vectorial seismic Intensity Measure is assumed to compute structural safety at large scale, and a change of variables is made to turn the traditional fragility curve into a matrix. Typological fragility matrices are processed and combined to define the so-called Urban Fragility Matrices, representative of the vulnerability of selected urban sectors. The procedure is then implemented and validated referring to the city of Pozzuoli (Southern Italy) and its effectiveness validated with reference to the damage survey relative to the 4th October 1983 seismic event which struck the city, resulting a good matching between predicted and observed scenarios. • A novel methodology for probabilistic safety assessment of buildings at large scale has been proposed. • Source-to-site disaggregation of ground motion has been taken into account used to define the seismic fragility. • A new tool, called urban fragility matrices, has been introduced to assess seismic fragility at large scale. • The proposed methodology has been validated with respect to the case study of Pozzuoli (southern Italy). [ABSTRACT FROM AUTHOR]

Objectives This study sought to assess the influence of baseline right bundle branch block (RBBB) on all-cause and cardiovascular mortality as well as sudden cardiac death (SCD) among patients undergoing transcatheter aortic valve replacement (TAVR). Background Few data exist regarding the late clinical impact of pre-existing RBBB in TAVR recipients. Methods A total of 3,527 patients (mean age 82 ± 8 years, 50.1% men) were evaluated according to the presence of RBBB on baseline electrocardiography. Intraventricular conduction abnormalities were classified according to the American Heart Association, American College of Cardiology Foundation, and Heart Rhythm Society recommendations for standardization and interpretation of the electrocardiogram. TAVR complications and causes of death were defined according to Valve Academic Research Consortium 2 definitions. Results RBBB was present on baseline electrocardiography in 362 patients (10.3%) and associated with higher 30-day rates of permanent pacemaker implantation (PPI) (40.1% vs. 13.5%; p < 0.001) and death (10.2% vs. 6.9%; p = 0.024). At a mean follow-up of 20 ± 18 months, pre-existing RBBB was independently associated with all-cause mortality (hazard ratio [HR]: 1.31; 95% confidence interval [CI]: 1.06 to 1.63; p = 0.014) and cardiovascular mortality (HR: 1.45; 95% CI: 1.11 to 1.89; p = 0.006) but not with SCD (HR: 0.71; 95% CI: 0.22 to 2.32; p = 0.57). Patients with pre-existing RBBB and without PPI at discharge from the index hospitalization had the highest 2-year risk for cardiovascular death (27.8%; 95% CI: 20.9% to 36.1%; log-rank p = 0.007). In a subanalysis of 1,245 patients without PPI at discharge from the index hospitalization and with complete follow-up regarding the need for PPI, pre-existing RBBB was independently associated with the composite of SCD and PPI (HR: 2.68; 95% CI: 1.16 to 6.17; p = 0.023). Conclusions Pre-existing RBBB was found in 10% of TAVR recipients and was associated with poorer clinical outcomes. Patients with baseline RBBB without permanent pacemakers at hospital discharge may be at especially high risk for high-degree atrioventricular block and/or SCD during follow-up. Future studies should evaluate strategies aimed at the early detection of patients at risk for late development of high-degree atrioventricular block. [ABSTRACT FROM AUTHOR]

• Experimental program on monotonic behavior of masonry spandrels reinforced by thin-steel stripes. • Seventeen tests on H -shaped scaled specimens. • Effect of different slenderness ratios on monotonic behavior. • Effect of different strengthening configurations to prevent brittle failure mechanisms. • Analysis of the benefits provided by steel stripes reinforcement on strength, stiffness and ductility. This paper presents the results of an experimental program conducted on H -shaped reduced-scale reinforced masonry spandrels subjected to monotonic loadings. It summarized tests units, test set-up and experimental results relative to seventeen samples reinforced by thin-steel stripes arranged with different configurations, and compared with those unreinforced. The first configuration comprised masonry spandrels strengthened by unbonded horizontal and diagonal steel stripes (i.e., stripes connected by means of threaded rods to the nodal area of the panel), while the second masonry spandrels reinforced by bonded horizontal stripes (i.e., stripes connected with 5 or 13 threaded rods over the spandrel length). For each reinforcement configuration, slender, intermediate and squat slenderness ratios have been considered for the samples. The conducted research investigated the effectiveness of the reinforcement to enhance the seismic response of the spandrels. Test results demonstrated that the application of steel stripes is beneficial in changing the failure modes from shear-dominated into flexural-dominated, especially for intermediate and squat panels prone to brittle shear mechanisms. Despite that increases of strength are reduced with respect to unreinforced samples, when reinforced the post-peak response changes significantly being it characterized by a remarkable ductile response for whatever spandrels' slenderness ratios. [ABSTRACT FROM AUTHOR]

• Experimental investigation on monotonic and cyclic behaviour of masonry spandrels reinforced by FRP. • Twenty-four tests on H-shaped scaled specimens. • Effect of different slenderness ratios on monotonic and cyclic behaviour. • Different strengthening configurations to prevent brittle failure modes. • Beneficial effect of some FRP configurations in term of strength, stiffness and ductility increases. This paper deals with the experimental monotonic and cyclic behavior of masonry spandrels reinforced with Fiber Reinforced Polymers (FRP). The research is a part of a wider program, started by the authors in the last decade, regarding the analysis of the seismic behavior of masonry spandrels in historical buildings of the Mediterranean area. The paper summarizes the properties of the test units, the test set-up and the results of the experimental monotonic and cyclic behavior conducted on twenty-four scaled down H -shaped spandrels made with homogeneous material (e.g. mortar with low tensile strength). Both unreinforced and FRP-reinforced specimens with three different slenderness ratios – e.g. slender, intermediate and squat – and three different arrangements of FRP laminates have been considered for the tests. The main objective has been to verify the possibility of preventing brittle failure modes, typical of spandrels subjected to in-plane seismic actions (e.g. diagonal cracking), and of increasing their strength by applying specific reinforcement systems, so encouraging more ductile behavior characterized by toe-crushing at the ends of the spandrels itself. [ABSTRACT FROM AUTHOR]

In early piggyback liver transplantation (LT) descriptions, the common stump of the middle and left hepatic veins (ML) was used for upper caval anastomosis. In this variant, stenosis or kinking of graft venous outflow path was frequent. Over time, most authors adopted the use of the recipient's right, middle, and left hepatic veins (RML) or a side-to-side anastomosis (SS) between the graft's and recipient's inferior vena cava (IVC). Nonetheless, partial IVC clamping required in RML and SS can reduce IVC flow. Since 1998, we incorporated a modified piggyback procedure using the recipient's right and middle hepatic veins (RM) to simultaneously achieve better preservation of IVC flow and a wide and well-positioned anastomosis. The aim of this study is to describe the RM method and to compare this technique with other standard variants of piggyback LT. We conducted a retrospective analysis of 477 piggyback LTs classified in 4 groups: ML (n = 102); RM (n = 171); RML (n = 150); and SS (n = 54). The incidence of venous outflow block was 3.9% (4/102) in ML, 2.3% (4/171) in RM, 0% (0/150) in RML, and 3.7% (2/54) in SS (P =.049). On Bonferroni multiple comparison analysis, no statistically significant paired difference was identified. Results showed that 1-, 3-, 5-, and 10-year patient survival was 76%, 67%, 63%, and 51% in the ML group; 80%, 71%, 68%, and 62% in the RM group; 77%, 75%, 70%, and 64% in the RML group; and 76%, 76%, 76%, and 70% in the SS group, respectively (P =.193). The RM modified piggyback LT technique is feasible and safe. [ABSTRACT FROM AUTHOR]

Background Little evidence exists of the burden and predictors of cardiac death after transcatheter aortic valve replacement (TAVR). Objectives The purpose of this study was to assess the incidence and predictors of cardiac death from advanced heart failure (HF) and sudden cardiac death (SCD) in a large patient cohort undergoing TAVR. Methods The study included a total of 3,726 patients who underwent TAVR using balloon (57%) or self-expandable (43%) valves. Causes of death were defined according to the Valve Academic Research Consortium–2. Results At a mean follow-up of 22 ± 18 months, 155 patients had died due to advanced HF (15.2% of total deaths, 46.1% of deaths from cardiac causes) and 57 had died due to SCD (5.6% of deaths, 16.9% of cardiac deaths). Baseline comorbidities (chronic obstructive pulmonary disease, atrial fibrillation, left ventricular ejection fraction ≤40%, lower mean transaortic gradient, pulmonary artery systolic pressure >60 mm Hg; p < 0.05 for all) and 2 procedural factors (transapical approach, hazard ratio [HR]: 2.38, 95% confidence interval [CI]: 1.60 to 3.54; p < 0.001; presence of moderate or severe aortic regurgitation after TAVR, HR: 2.79, 95% CI: 1.82 to 4.27; p < 0.001) independently predicted death from advanced HF. Left ventricular ejection fraction ≤40% (HR: 1.93, 95% CI: 1.05 to 3.55; p = 0.033) and new-onset persistent left bundle-branch block following TAVR (HR: 2.26, 95% CI: 1.23 to 4.14; p = 0.009) were independently associated with an increased risk of SCD. Patients with new-onset persistent left bundle-branch block and a QRS duration >160 ms had a greater SCD risk (HR: 4.78, 95% CI: 1.56 to 14.63; p = 0.006). Conclusions Advanced HF and SCD accounted for two-thirds of cardiac deaths in patients after TAVR. Potentially modifiable or treatable factors leading to increased risk of mortality for HF and SCD were identified. Future studies should determine whether targeting these factors decreases the risk of cardiac death. [ABSTRACT FROM AUTHOR]

We have studied the elastic scattering of the exotic 17F nuclei from 208Pb at Coulomb barrier energies. For the measurement we used a new detector array with pixel structure and a large solid angle. Optical potential analysis shows that 17F has an imaginary potential much less deep than 19F. Information on the exclusive 17F breakup cross section has been deduced too. [Copyright &y& Elsevier]

The EXOTIC collaboration is installing a facility for the in flight production of exotic ion beams at INFN Legnaro National Laboratories (LNL). The RIBs are produced in inverse kinematics mode via intense TANDEM/ALPI primary beams hitting a light gas target (H, d, 3He, 4He). The results of the optics calculation for 17F produced by the 17O(p,n)17F reaction are presented. Special care has been adopted to stop, at several points perpendicular to the beam direction, the contaminants due to the primary beam. [Copyright &y& Elsevier]

PRISMA is a magnetic spectrometer for heavy ions under construction at Legnaro, with very large solid angle (80 msr), wide momentum acceptance (± 10%) and good mass resolution via TOF measurement; it will be dedicated to the study of nuclear dynamics and nuclear structure with stable and exotic ion beams. This is a review of its main features and of the present status of the project. [Copyright &y& Elsevier]

• The stop-splayed scarf joint unreinforced and reinforced with timber pegs are studied. • The stop-splayed scarf joint unreinforced and reinforced with steel pins are studied. • Three samples of fir scarf joints with different configurations have been tested. • The results have been presented in tabular and graphical form. • Comparison of the experimental and theoretical results have been discussed. In restoring ancient timber structures, employing traditional connections would be advisable with the aim of minimal modification of the overall structural behaviour. Moreover, instead of steel connectors or adhesive resins and rods, commonly used in interventions, employing timber pegs can be an efficient solution. Nevertheless, the lack of design rules for traditional timber joints or for timber pegged connections in European codes doesn't encourage this more conservative approach. In this study, stop-splayed scarf joints behaviour before and after reinforcement with steel pins or timber pegs is experimentally investigated, in order to understand the role of the fastener inside this carpentry joint and check the reliability of existing design methods. The experimental program has two steps: in the first one, three samples of fir scarf joints without fasteners, with timber pegs and with steel pins have been tested, trying to define the forces distribution among the different resisting elements. In the second phase, two samples of simple shear plane joints, made with the same timber and fastened with both timber pegs and steel pins have been tested to improve the analysis of fastener role in reinforced scarf joint behaviour. [ABSTRACT FROM AUTHOR]

Abstract: The dynamical dipole mode, excited in charge asymmetric heavy-ion collisions, was investigated in the mass region of the 192Pb compound nucleus, formed by using the 40,48Ca + 152,144Sm reactions at ∼11 MeV/nucleon. Preliminary results of this measurement, concerning both fusion-evaporation and fission events are presented. As a fast cooling mechanism on the fusion path, the dynamical dipole mode could be useful for the synthesis of super heavy elements through “hot” fusion reactions. [Copyright &y& Elsevier]