Li1.4Al0.4Ge0.4Ti1.4(PO4)3 promising NASICON-structured glass-ceramic electrolyte for all-solid-state Li-based batteries: Unravelling the effect of diboron trioxide

Li-ion batteries (LIBs) are the ubiquitous technology to power portable electronics; however, for the next-generation of high-performing electrochemical energy storage systems for electric vehicles and smart grid facilities, breakthroughs are needed, particularly in the development of solid-state electrolytes, which may allow for enhanced energy density while enabling lithium metal anodes, combined with unrivalled safety and operative reliability. In this respect, here we present the successful synthesis of a glass-ceramic Li1.4Al0.4Ge0.4Ti1.4(PO4)3 NASICON-type solid-state electrolyte (SSE) through a melt-casting technique. Being grain boundaries crucial for the total ionic conductivity of SSEs, the effect of the addition of diboron trioxide (B2O3, 0.05 wt.%) to promote their liquefaction and restructuring is investigated, along with the effects on the resulting microstructures and ionic conductivities. By the thorough combination of structural-morphological and electrochemical techniques, we demonstrate that bulk materials show improved performance compared to their powder sintered counterpart, achieving remarkable ion mobility (> 0.1 mS cm–1 at –10 °C) and anodic oxidation stability (> 4.8 V vs Li+/Li). The addition of B2O3 positively affects the grain cohesion and growth, thus reducing the extension of the grain boundaries (and the related grain/grain interface resistance) and, therefore, increasing the overall ion mobility. In addition, B2O3 is seen to contrast the microcracks formation in the LAGTP system under study which, overall, shows very promising prospects as SSE for the next-generation of high-energy density, safe lithium-based batteries

From particle systems to the Landau equation: a consistency result

We consider a system of N classical particles, interacting via a smooth, short- range potential, in a weak-coupling regime. This means that N tends to infinity when the interaction is suitably rescaled. The j-particle marginals, which obey to the usual BBGKY hierarchy, are decomposed into two contributions: one small but strongly oscillating, the other hopefully smooth. Eliminating the first, we arrive to establish the dynamical problem in term of a new hierarchy (for the smooth part) involving a memory term. We show that the first order correction to the free flow converges, as N \rightarrow \infty, to the corresponding term associated to the Landau equation. We also show the related propagation of chaos.Comment: 21 page

EMOTIONAL FLUCTUATIONS OF BLOOD PRESSURE IN ADOLESCENTS: INFLUENCE OF THE REPETITION OF THE MEASUREMENT

Background. The optimal methodology to measure blood pressure (BP) in children remains controversial. Particularly relevant is the concern that anxiety may trigger a rising in BP during the first measurement, while the second and/or the third reading is lower because the child is more relaxed. However, experimental data concerning the pattern of repeated readings of BP are almost non existent. Therefore we accurately examined, by a repeated measures ANOVA design, the pressor response of a large group of healthy children, during the adolescent growth, to three consecutive BP measurements separated by one minute. Method. From a larger group of 719 well-being children aged 5-15 years examined in our hospital between July 2004 and March 2005, a cohort of 145 age-eligible children (11-14 years) was selected for this study. In each subject, BP readings were carried out in the supine position placing size-appropriate cuffies on the right arm and by making use of an oscillometric monitor, whose reliability is unaffected by the enviromental noise. Anthropometric parameters also were acquired. Data were analysed with a PC based statistic package (SPSS for Windows) testing the within-subjects differences. Results and conclusions. Data from the study are shown in the figure

Severe parainfluenza pneumonia in a case of transient hypogammalobulinemia of infancy

Human parainfluenza viruses (HPIVs) infection, largely known to cause self-limiting bronchiolitis and pneumonia in immune competent patients, can lead to severe to fatal pulmonary disease in immune disorders, such as primary or acquired-immune deficiencies. We report the case of a 1-year-old child who developed an acute respiratory distress syndrome. Because of a progressive respiratory failure unresponsive to conventional treatment extracorporeal membrane oxygenation (ECMO) was rapidly started. HPIV-3 infection was diagnosed on the rhinopharyngeal fluid and immunological examinations revealed a hypogammaglobulinemia. A combination therapy with ribavirin, intravenous immunoglobulin (IVIG) and steroid under ECMO support was started with considerable improvement. Subsequent analysis and more specific immunological assessment resulted normal confirming the diagnosis of transient hypogammaglobulinemia of infancy (THI). This case highlights the importance of prompt therapy with early ECMO support in combination with ribavirin, IVIG and steroids in patients affected by severe HPIV-3 pneumonia and THI

New findings concerning cardiovascular manifestations emerging from long-term follow-up of 150 patients with the Williams-Beuren-Beuren syndrome.

AIMS: We investigated the prevalence, type, and course of congenital cardiac defects and systemic hypertension in our patients with Williams-Beuren-Beuren syndrome. METHODS AND RESULTS: We reviewed the clinical records of all patients with Williams-Beuren syndrome examined between 1981 and 2006. We identified 150 patients, aged from 7 months to 45 years, with a follow-up from 6 months to 25 years, the mean being 6.4 years. A cardiac anomaly was present in 113 of the 150 patients (75%). Defects were typical in over four-fifths of the group. We found supravalvar aortic stenosis in 73 of 113 patients (64.6%), isolated in 43. Pulmonary stenosis, isolated in 18 cases, was found in 51 of 113 (45.1%), while aortic coarctation and mitral valvar prolapse were each found in 7 (6.2%), 3 of the lesions is isolation. Atypical defects were found in 19 patients, tetralogy of Fallot in 2, atrial septal defects in 4, aortic and mitral valvar insufficiencies in 1 each, bicuspid aortic valves in 2, and ventricular septal defects in 9, 4 of the last being isolated. Systemic hypertension, observed in 33 patients (22%), was poorly controlled in 10. Diagnostic and/or interventional cardiac catheterization was undertaken in 24 patients, with 30 surgical procedures performed in 26 patients. Of the group, 3 patients died. CONCLUSION: Cardiac defects were present in three-quarters of our patients. Pulmonary arterial lesions generally improved, while supravalvar aortic stenosis often progressed. Atypical cardiac malformations, particularly ventricular septal defects, occurred frequently. Systemic hypertension was found in one-fifth, even in the absence of structural cardiac defects. The short-term mortality was low