The Fire Risk in Photovoltaic Installations – Checking the PV Modules Safety in Case of Fire☆

Abstract The installation of photovoltaic systems on buildings involves several problems, including the risk of fire (2011, Italy: 298 Fire fighters interventions; 2012, Germany: 390 established PV plant fires), which many countries are trying to solve. Standards focused specifically on fire behavior of PV modules don't exist yet. Currently, test protocols focused on other equipment are used to test PV modules fire reaction. About that, a research program was carried out to do a short analysis of PV systems fire events and to analyze the current test protocols to identify criticalities and possible improvements / protocols variants

The Fire Risk in Photovoltaic Installations - Test Protocols For Fire Behavior of PV Modules

Abstract The fire risk in the photovoltaic systems has emerged over the years as not negligible, setting in motion a process, which involves various organizations (control Authorities, standardization bodies, modules manufacturers, etc.) for achieving the codification of construction, design and installation of these systems and their components to minimize fire risk. Currently, European standards focused specifically on fire behavior of PV modules don't exist yet, so test protocols focused on other equipment are used to test PV modules reaction to fire. About that, a research program was carried out to do a short analysis of PV systems fire events, to analyze the current test protocols and for identifying their criticalities and possible improvements. In particular, some variants of these protocols have been developed basing on some of the existing test protocols in standard harmonized at European level about reaction to fire of construction products. These variants have been designed for being specific test tools for determination of reaction to fire features of PV modules with main attention to important peculiarities such as: modules inclination, initial fire particularly aggressive

An Unusual Hypopharyngeal Foreign Body Causing Dyspnea After Vertebroplasty

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AN INTRODUCTION TO THE BOLTZMANN FACTOR BY USING INFORMATION TECHNOLOGY TOOLS

Abstract We present an experiment and simulations aimed at introducing the Boltzmann factor mathematical expression and at illustrating the fundamental concepts on which it is grounded. The experiment uses an easily available Microcomputer Based Laboratory apparatus. Simulations are developed in the Net-Logo environment that, besides having a friendly user-interface, allows an easy interaction with the algorithm. The approach supplies a pedagogical support for the introduction of the Boltzmann factor at undergraduate level to students without a background in statistical mechanics

Ambipolar suppression of superconductivity by ionic gating in optimally-doped BaFe2(As,P)2 ultrathin films

Superconductivity (SC) in the Ba-122 family of iron-based compounds can be controlled by aliovalent or isovalent substitutions, applied external pressure, and strain, the combined effects of which are sometimes studied within the same sample. Most often, the result is limited to a shift of the SC dome to different doping values. In a few cases, the maximum SC transition at optimal doping can also be enhanced. In this work, we study the combination of charge doping together with isovalent P substitution and strain by performing ionic gating experiments on BaFe$_2$(As$_{0.8}$P$_{0.2}$)$_2$ ultrathin films. We show that the polarization of the ionic gate induces modulations to the normal-state transport properties that can be mainly ascribed to surface charge doping. We demonstrate that ionic gating can only shift the system away from the optimal conditions, as the SC transition temperature is suppressed by both electron and hole doping. We also observe a broadening of the resistive transition, which suggests that the SC order parameter is modulated nonhomogeneously across the film thickness, in contrast with earlier reports on charge-doped standard BCS superconductors and cuprates.Comment: 10 pages, 5 figure

Therapy with different dose regimens of rituximab in patients with active moderate-to-severe Graves' Orbitopathy

Background: Immunosuppressive therapy of Graves’ orbitopathy (GO) is indicated during the active phase of disease. Intravenous steroids (IVGC) are effective in about 70% of patients, although unresponsiveness or relapse are observed. In previous studies, rituximab (RTX) has been shown to be effective in inactivating moderate-to-severe GO when used early in the disease, but its optimal dosage has never been studied in randomized clinical trials. Aim of this study was to compare the efficacy and safety of different doses of RTX, based on a post-hoc analysis of two open label studies and one prospective trial randomized to IVGC. Methods: of 40 patients (35 women, 5 men), with active moderate-to-severe GO treated with RTX, 14 received a single dose of 100 mg (Group 1), 15 a single dose of 500 mg (Group 2) and 11 two 1000 mg doses, administered one week apart (Group 3). Thyroid function, TSH-receptor antibodies (TRAb) and peripheral CD19+ cells were measured. Primary endpoint was disease inactivation, measured as a decrease of the Clinical Activity Score (CAS) of at least two points. Secondary endpoints were improvement of proptosis, diplopia, quality of life and safety. Results: Baseline CAS decreased significantly in all groups (P<0.0001), independently of GO duration or whether patients had newly occurring or relapsing GO after IVGC. Proptosis did not significantly change. There was an inverse correlation between the Gorman score for diplopia and RTX dose (P<0.01). The appearance score of the GO-QoL improved in Group 1 (P=0.015), and the visual function score, in Group 2 (P=0.04). A reduction of serum TRAb was observed in Group 1 (P=0.002) and Group 2 (P<0.0002), but not in Group 3. CD19+ cell decreased in all groups (P<0.01), independently of the dose. Conclusions: We studied the optimal dosage of RTX in the treatment of active moderate-to-severe GO. In this analysis, we considered the efficacy of RTX in inactivating GO, in changing its natural course, its effect on disease severity and on the patients’ quality of life. Based on our clinical findings, and balancing the cost of therapy, a single 500 mg dose regimen is suggested in the majority of patients

Collisions and mechanical wave propagation in elastic rods

Some results from experiments intended to measure the propagation speed of sound waves produced by collisions between small bodies and metallic rods are analysed. Elementary models of elastic collision and of the reflection and transmission of waves at media boundaries are discussed and tested with experimental data, in the framework of a workshop on mechanical wave propagation that featured at the University of Palermo in a two-year graduate programme for prospective physics teachers and in courses for undergraduate engineering and physics students