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Shape memory alloys (SMAs) and ferromagnetic shape memory alloys (FeSMAs) have recently attracted interest for solid state refrigeration applications. Among NiMnGa-based quaternary systems, NiMnGaCu exhibits an interesting giant magnetocaloric effect thanks to the overlapping of the temperatures related to the magnetic transition and the thermoelastic martensitic transformation (TMT); in particular, for compositions with Cu content of approximately 6 at%. In the present work, we investigated the improvement effect of TMT on the total entropy change (ΔS) in the elastocaloric performances of polycrystalline Ni50Mn18.5Cu6.5Ga25 at% alloy samples, just above room temperature. We report an extensive calorimetric and thermomechanical characterization to explore correlations between microstructural properties induced by the selected thermal treatment and elastocaloric response, aiming at providing the basis to develop more efficient materials based on this quaternary system. Both ΔT and ΔS values obtained from mechanical curves at different temperatures and strain recovery tests under fixed load vs. T were considered. Maximum values of ΔS = 55.9 J/KgK and ΔT = 4.5 K were attained with, respectively, a stress of 65 MPa and strain of 4%. The evaluation of the coefficient of performance (COP) was carried out from a cyclic test. [ABSTRACT FROM AUTHOR]

Conventional high-chromium ferritic / martensitic steels, such as T91 and AISI 316 L as well as the new oxide dispersed strengthened (ODS) steels, i.e. Fe-Cr (ferritic or martensitic) with a fine Y2O3 dispersion, are promising candidates as structural materials for applications in aggressive environments. In order to improve the efficiency and lifetime of structural materials for liquid metal fast reactor (LMFR), where liquid lead (Pb) is used as coolant, the investigations are currently focused on the interfacial phenomena occurring at the liquid Pb/steel interfaces. The better understanding of the interfacial phenomena is the key issue for the selection of structural materials meeting the requirements of the demanding application. In the present work, a fundamental study on the wetting characteristics and the interfacial phenomena of liquid Pb in contact with T91, AISI 316L, ODS-12Cr and ODS-14Cr steels over the temperature range 550-820°C and under different oxygen containing atmospheres is reported. [ABSTRACT FROM AUTHOR]

Aims: The aim of this study is to report heart failure hospitalization (HFH) rates and associated costs within 12 months following implantable cardioverter defibrillator (ICD)/cardiac resynchronization therapy defibrillator (CRT‐D) device replacement or upgrade from ICD to CRT‐D. Methods and results: The DEtect long‐term COmplications after icD rEplacement (DECODE) was a prospective, single‐arm, multicentre cohort study that explored complications in ICD/CRT‐D recipients. All clinical and survival data at 12 months were prospectively analysed. For each adjudicated HFH, admission and discharge dates and ICD‐9‐CM diagnosis and procedure codes were recorded. The reimbursement for each HFH was calculated for each diagnosis‐related group code. Between 2013 and 2015, 983 patients (mean age 71 years, male 76%, mean left ventricular ejection fraction 35%, and New York Heart Association Class I/II 75.6%) were enrolled. Patients underwent device replacement (900; 91.6%, 446 ICD/454 CRT‐D) or ICD upgrade to CRT‐D (83; 8.4%). Post‐replacement hospitalizations occurred in 220 patients, with the primary discharge diagnosis identifying cardiovascular causes in 175 patients (80%). Fifty‐five (5.6%) patients experienced at least one HFH. Overall, 91 HFH events occurred (9.6% event rate, 95% confidence interval: 7.7–11.7) in 70 patients; 66 (6.7%) patients died, 40 (60.6%) of cardiovascular causes. The HFH rate was significantly higher following upgrades, and the occurrence of HFH was associated with an 11‐fold increased mortality risk (95% confidence interval: 5.9–20.5, P < 0.0001). Medical diagnosis‐related group accounted for 91.2% of HFH; the mean cost per HFH was €5662 ± 9497, and the mean cost per patient was €9369 ± 12 687. On multivariate analysis, predictors of HFH were atrial fibrillation, chronic kidney disease, and all‐cause hospitalization within 30 days prior to the procedure. Conclusions: In the DECODE registry, HFH and mortality rates in the year following ICD/CRT‐D replacement or upgrade were low. In this particular subset, underlying cardiac disease was the main driver of HFH, mortality, and higher healthcare expenditures. [ABSTRACT FROM AUTHOR]

The extended x-ray absorption fine structure at the Ln [L.sub.III] edges were used to study the local chemical environment of [Nd.sup.3+], [Eu.sup.3+], and Er.sup.3+] luminescent centers in various lead germanate glasses.The results showed that for all the [Ln.sup.3+] ions, first coordination sphere is more symmetrical in glasses with high lead concentration than in glasses with low Pb content.

A new model is proposed to explain the transport properties of Agl-based fast ion conducting glasses. The nature of glass network, and namely its connectivity and dimensionality, plays a significant role only for iodine/oxygen values, originating the transport and thermal anomalies observed in borate and phosphate glasses.

Atrial fibrillation (AF) carries out a 5-fold increase in stroke risk, related to embolization of thrombi clotting in left atrium (LA). Left atrial appendage (LAA) is the site with the highest blood stasis which causes thrombus formation. About 90 % of the intracardiac thrombi in patients with cardioembolic events originally develop in the LAA. Recent studies have been focused on the association between LAA anatomical features and stroke risk and provided conflicting results. Haemodynamic and fluid dynamic information on the LA and mostly on the LAA may improve stroke risk stratification. Therefore, the aim of this study was the design and development of a workflow to quantitatively define the influence of the LAA morphology on LA hemodynamics. Five 3D LA anatomical models, obtained from real clinical data, which were clearly different as regard to LAA morphology were used. For each LAA we identified and computed several parameters describing its geometry. Then, one LA chamber model was chosen and a framework was developed to connect the different LAAs belonging to the other four patients to this model. These new anatomical models represented the computational domain for the computational fluid dynamics (CFD) study; simulations of the hemodynamics within the LA and LAA were performed in order to evaluate the interplay of the LAA shape on the blood flow characteristics in AF condition. CFD simulations were carried out for five cardiac cycles. Blood velocity, vorticity, LAA orifice velocity, residence time computed in the five models were compared and correlated with LAA morphologies. Results showed that not only complex morphologies were characterized by low velocities, low vorticity and consequently could carry a higher thrombogenic risk; even qualitatively simple morphologies showed a thrombogenic risk equal, or even higher, than more complex auricles. CFD results supported the hypothesis that LAA geometric characteristics plays a key-role in defining thromboembolic risk. LAA geometric parameters could be considered, coupled with the morphological characteristics, for a comprehensive evaluation of the regional blood stasis. The proposed procedure might address the development of a tool for patient-specific stroke risk assessment and preventive treatment in AF patients, relying on morpho-functional defintion of each LAA type. [ABSTRACT FROM AUTHOR]

Background: The impact on long-term outcomes of implantable cardioverter defibrillators (ICDs) and biventricular defibrillators for cardiac resynchronization (CRT-D) devices in 'real world' patients with heart failure (HF) needs to be assessed in terms of clinical effectiveness.Methods and Results: A registry including consecutive HF patients who underwent a first implant of an ICD (891 patients) or a CRT-D device (709 patients) in 2006-2010 was followed (median 1487 days and 1516 days, respectively), collecting administrative data on survival, all-cause hospitalizations, cardiovascular or HF hospitalizations, and days alive and out of hospital (DAOH). Survival free from death/cardiac transplant was 61.9% and 63.8% at 5 years for ICD and CRT-D patients, respectively. Associated comorbidities (Charlson Comorbidity Index) had a significant impact on death/cardiac transplant, as well as on hospitalizations. The median values of DAOH% were 97.4% for ICD and 97.7% for CRT-D patients, but data were highly skewed, with the lower quartile of DAOH% values including values ranging between 0% and 52.8% for ICD and between 0% and 56.1% for CRT-D patients. Charlson Comorbidity Index was a very strong predictor of DAOH%.Conclusions: Patients who were implanted in 'real world' clinical practice with an ICD or a CRT-D device have, on average, a relatively favourable outcome, with a survival of around 62-64% at 5 years, but with an important burden of hospitalizations. Comorbidities, as evaluated by means of the Charlson Comorbidity Index, have a significant impact on outcomes in terms of mortality/heart transplant, hospitalizations and days spent alive and out of hospital. [ABSTRACT FROM AUTHOR]

Background: The impact on long-term outcomes of implantable cardioverter defibrillators (ICDs) and biventricular defibrillators for cardiac resynchronization (CRT-D) devices in 'real world' patients with heart failure (HF) needs to be assessed in terms of clinical effectiveness. Methods and results: A registry including consecutive HF patients who underwent a first implant of an ICD (891 patients) or a CRT-D device (709 patients) in 2006-2010 was followed (median 1487 days and 1516 days, respectively), collecting administrative data on survival, all-cause hospitalizations, cardiovascular or HF hospitalizations, and days alive and out of hospital (DAOH). Survival free from death/cardiac transplant was 61.9% and 63.8% at 5 years for ICD and CRT-D patients, respectively. Associated comorbidities (Charlson Comorbidity Index) had a significant impact on death/cardiac transplant, as well as on hospitalizations. The median values of DAOH% were 97.4% for ICD and 97.7% for CRT-D patients, but data were highly skewed, with the lower quartile of DAOH% values including values ranging between 0% and 52.8% for ICD and between 0% and 56.1% for CRT-D patients. Charlson Comorbidity Index was a very strong predictor of DAOH%. Conclusions: Patients who were implanted in 'real world' clinical practice with an ICD or a CRT-D device have, on average, a relatively favourable outcome, with a survival of around 62-64% at 5 years, but with an important burden of hospitalizations. Comorbidities, as evaluated by means of the Charlson Comorbidity Index, have a significant impact on outcomes in terms of mortality/heart transplant, hospitalizations and days spent alive and out of hospital. [ABSTRACT FROM AUTHOR]

Abstract: Boron neutron capture therapy (BNCT) is a radiotherapy treatment based on the accumulation in the tumor of a 10B-containing drug and subsequent irradiation with low energy neutrons, which bring about the decay of 10B to 7Li and an α particle, causing the death of the neoplastic cell. The effectiveness of BNCT is limited by the low delivery and accumulation of the used boron-containing compounds. Here we report the development and the characterization of BPO4 nanoparticles (NPs) as a novel possible alternative drug for BNCT. An extensive analysis of BPO4 NP biocompatibility was performed using both mature blood cells (erythrocytes, neutrophils and platelets) and a model of hematopoietic progenitor cells. A time- and concentration-dependent cytotoxicity study was performed on neoplastic coloncarcinoma and osteosarcoma cell lines. BPO4 functionalization with folic acid, introduced to improve the uptake by tumor cells, appeared to effectively limit the unwanted effects of NPs on the analyzed blood components. From the Clinical Editor: Boron neutron capture therapy (BNCT) is a radiotherapy treatment modality based on the accumulation of a 10B-containing drug and subsequent irradiation with low energy neutrons, inducing the decay of 10B to 7Li and an α particle, causing neoplastic cell death. This team of authors reports on a folic acid functionalized BPO4 nanoparticle with improved characteristics compared with conventional BNCT approaches, as demonstrated in tumor cell lines, and hopefully to be followed by translational human studies. [Copyright &y& Elsevier]

Polybenzimidazoles are promising materials to replace Nafion™ as the electrolyte in HT-PEMFCs. One of their problems is striking the proper balance between the H3PO4 doping level, which controls the proton conductivity, and the long-term stability properties of the membrane. Monomer modification is a promising way to maintain high conductivity levels with reduced doping. Here, we reported a novel and facile approach to obtaining an easy modular and reproducible sulfonation degree. Some aryloxy-based polybenzimidazoles were synthesized and sulfonated with different amounts of –SO3H. We prepared many electrolyte membranes by doping the pristine polymers in solutions with different H3PO4 concentrations. The sulfonation degree greatly affected both acid uptake and conductivity. In particular, the membranes holding more protogenic groups absorbed less acid than the monosulfonated ones. However, polysulfonation was particularly efficient in improving proton conductivity at low relative humidity and doping level. We performed MEAs tests at 150 °C using H2 and air as the reactant gases, without any external humidification. We obtained power densities higher than 320 mW cm−2, with fuel cell performances of approximately 580 mV at 0.2 A cm−2, independent of the number of sulfonic groups. Preliminary durability tests did not show any membrane degradation over a 190 hour period. The reported membranes are therefore suitable for use in HT-PEMFCs. [ABSTRACT FROM AUTHOR]

AgI : AgPO[sub 3] glasses are an interesting model system in which to address the relationships between carrier density and mobility, transport mechanism and medium-range order in fast ion-conducting glasses. In this paper we discuss an anomaly observed in the dc conductivity behaviour below room temperature. This anomaly is related to the opening of percolative channels for AgI contents higher than 30 mol%. Solid-state [sup 109]Ag nuclear magnetic resonance (NMR) measurements on the 1 : 1 AgI : AgPO[sub 3] glass allow us to determine the change in the number of mobile carriers over all the temperature region where the anomaly is observed. [ABSTRACT FROM AUTHOR]

Two composite gel electrolytes prepared from mixtures of poly(acrylonitrile) (PAN), propylene carbonate (PC), ethylene carbonate (EC) and LiClO have been studied with differential scanning calorimetry (DSC) andLi-Li NMR. The data allow estimation of ionic conductivities, local (short range) diffusivities, and lattice dynamics. Furthermore, they point to an unexpected behavior of the Li-rich sample that hints to a complex LiClO-PAN phase diagram. [ABSTRACT FROM AUTHOR]