Italian guidelines for primary headaches: 2012 revised version

The first edition of the Italian diagnostic and therapeutic guidelines for primary headaches in adults was published in J Headache Pain 2(Suppl. 1):105–190 (2001). Ten years later, the guideline committee of the Italian Society for the Study of Headaches (SISC) decided it was time to update therapeutic guidelines. A literature search was carried out on Medline database, and all articles on primary headache treatments in English, German, French and Italian published from February 2001 to December 2011 were taken into account. Only randomized controlled trials (RCT) and meta-analyses were analysed for each drug. If RCT were lacking, open studies and case series were also examined. According to the previous edition, four levels of recommendation were defined on the basis of levels of evidence, scientific strength of evidence and clinical effectiveness. Recommendations for symptomatic and prophylactic treatment of migraine and cluster headache were therefore revised with respect to previous 2001 guidelines and a section was dedicated to non-pharmacological treatment. This article reports a summary of the revised version published in extenso in an Italian version

Enhanced electrocaloric and pyroelectric response from ferroelectric multilayers

Room temperature pyroelectric properties and adiabatic temperature change of (001)-textured ferroelectric multilayers on Si are computed by taking into account electrostatic interlayer interactions and thermal strains. We show that by adjusting internal electrical fields through changing relative thicknesses in a multilayer ferroelectric construct, electrothermal properties can be significantly enhanced. A quantitative analysis is provided for BaTiO 3-PbZr0.2Ti0.8O3 (BTO-PZT) and SrTiO3-PbZr0.2Ti0.8O3 (STO-PZT) multilayers. For instance, 0.74×BTO-0.26×PZT and 0.35×STO-0.65×PZT bilayers show ∼120% and 65% increase in electrocaloric response, respectively, compared to PZT films on Si for Δ E=500kV/cm. © 2014 AIP Publishing LLC

Enhanced electrocaloric and pyroelectric response from ferroelectric multilayers

Room temperature pyroelectric properties and adiabatic temperature change of (001)-textured ferroelectric multilayers on Si are computed by taking into account electrostatic interlayer interactions and thermal strains. We show that by adjusting internal electrical fields through changing relative thicknesses in a multilayer ferroelectric construct, electrothermal properties can be significantly enhanced. A quantitative analysis is provided for BaTiO 3-PbZr0.2Ti0.8O3 (BTO-PZT) and SrTiO3-PbZr0.2Ti0.8O3 (STO-PZT) multilayers. For instance, 0.74×BTO-0.26×PZT and 0.35×STO-0.65×PZT bilayers show ∼120% and 65% increase in electrocaloric response, respectively, compared to PZT films on Si for Δ E=500kV/cm. © 2014 AIP Publishing LLC

Hyperbranched polymers. Synthesis, modeling, experimental validation, and rheology of hyperbranched poly(methyl methacrylate) derived from a multifunctional monomer (MFM) route

The synthesis of hyperbranched PMMA has been achieved using a facile one-step batch solution polymerization reaction. The reaction is essentially a linear polymerization doped with appropriate amounts of a multifunctional monomer (MFM) and chain transfer agent (CTA). On this basis, a theoretical model for the MFM reaction has been developed and experimentally validated for the number-aver age molecular weight and degree of branching data, by assuming isothermal batch conditions and employing key reaction parameters from established linear PMMA kinetics. A first comparison of the melt rheology of the hyperbranched polymer with that of the linear one revealed a significant reduction in melt viscosity and shear thinning. It is expected that the generic model developed here will guide the manufacture of other free-radical hyperbranched polymers, of desired architecture or physical properties, using modeling and optimization methods. © 2005 American Chemical Society

Polymerisation of methyl methacrylate in a pilot-scale tubular reactor: Modelling and experimental studies

A pilot-scale tubular reactor fitted with in-line static mixers is experimentally and theoretically evaluated for the polymerisation of methyl methacrylate (MMA). A non-isothermal and non-adiabatic axially dispersed plug-flow model is used to describe the flow characteristics of the reactor. The model is applied to the polymerisation of a concentrated MMA solution (up to 72% (v/v)). Key model parameters were attained through independent bench and pilot-scale experiments. Measured monomer conversions and polymer molecular weight were accurately predicted by model simulation. The presence of static mixers is shown to give near-ideal plug-flow operation for the experimental conditions of this study. Furthermore, an approximately four-fold increase in overall heat transfer coefficient is indicated due to the radial mixing incited by the mixers. Studies also demonstrated the importance of inhibitor kinetics on the dynamic and steady-state performance of the reactor. © 2003 Elsevier Science Ltd. All rights reserved

Hyperbranched polymers. Synthesis, modeling, experimental validation, and rheology of hyperbranched poly(methyl methacrylate) derived from a multifunctional monomer (MFM) route

The synthesis of hyperbranched PMMA has been achieved using a facile one-step batch solution polymerization reaction. The reaction is essentially a linear polymerization doped with appropriate amounts of a multifunctional monomer (MFM) and chain transfer agent (CTA). On this basis, a theoretical model for the MFM reaction has been developed and experimentally validated for the number-aver age molecular weight and degree of branching data, by assuming isothermal batch conditions and employing key reaction parameters from established linear PMMA kinetics. A first comparison of the melt rheology of the hyperbranched polymer with that of the linear one revealed a significant reduction in melt viscosity and shear thinning. It is expected that the generic model developed here will guide the manufacture of other free-radical hyperbranched polymers, of desired architecture or physical properties, using modeling and optimization methods. © 2005 American Chemical Society