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In this paper, using suitable three-dimensional finite element method (FEM) approaches, either in frequency or in time domain, we will analyze the real magnetic behavior of a commercial Epstein machine, prescribed as standard magnetic measurement system. The analysis of magnetic field and eddy currents explains some facts that can affect the accuracy of Epstein frames as measuring systems for the magnetic characterization of laminated Si-Fe steels. The same FEM approaches shall be applied here to outline and define quantitatively some advantages in accuracy can be obtained using Single Sheet testers instead of Epstein frames. Index Terms--Epstein frame, magnetic steel, nonlinear FEM analysis, Single Sheet tester.

The sintering is an essential step in the processing of ceramics materials. A number of researchers have reported new techniques for sintering. However, in general, the process still demands high temperatures. This paper reports the results of the cold sintering of ZnO-BaTiO3 composites. The microstructural, structural, and electric properties of the composite were studied. We obtained high densities (>95%) for pure ZnO and for the composition with 10 wt% of BaTiO3 at a low temperature of sintering (250 °C/1 h). The increase of BaTiO3 content reduced the grain size and degraded the sinterability of ZnO. The crystalline structure was investigated by X-ray diffraction and confirmed the separation of the phases after the cold sintering. The BaTiO3 added in the composite reduced the values of conductivity, permittivity, and also the dielectric loss. [ABSTRACT FROM AUTHOR]

Real-life data concerning dupilumab effectiveness and safety in adolescents (aged >= 12 to <18 years) with moderate to severe atopic dermatitis (AD) are rarely reported.1 In two adolescence studies, the phase III randomized, placebo-controlled, clinical trial (LIBERTY AD ADOL)2 and the phase IIa and subsequent phase III open-label extension (LIBERTY AD PED-OLE)3 dupilumab produced significant improvement in signs and symptoms at Week 16, with a good safety profile. The issue of dupilumab therapy was under debate during COVID-19 pandemic first wave.4 In the Italian experience on 1576 patients under dupilumab treatment, 15 patients contracted SARS-CoV-2 infection with a good clinical outcome, confirming that dupilumab should be continued during the COVID-19 pandemic.5 Nevertheless, systematic studies are needed to evaluate the effect of dupilumab in patients with SARS-CoV-2 infection. Two of our patients (22.2%) achieved completely clear skin, compared with none of patients included in the previous trials.2,3 Additionally, we observed a greater improvement in patients with low BMI and high EASI at baseline. [Extracted from the article]

The structural, dielectric, and vibrational properties of pure and rare earth (RE)-doped Ba0.77Ca0.23TiO3 (BCT23; RE = Nd, Sm, Pr, Yb) ceramics obtained via solid-state reaction were investigated. The pure and RE-doped BCT23 ceramics sintered at 1450 °C in air for 4 h showed a dense microstructure in all ceramics. The use of RE ions as dopants introduced lattice-parameter changes that manifested in the reduction of the volume of the unit cell. RE-doped BCT23 samples exhibit a more homogenous microstructure due to the absence of a Ti-rich phase in the grain boundaries as demonstrated by scanning electron microscopy imaging. The incorporation of REs led to perturbations of the local symmetry of TiO6 octahedra and the creation of a new Raman mode. The results of Raman scattering measurements indicated that the Curie temperature of the ferroelectric phase transition depends on the RE ion and ion content, with the Curie temperature shifting toward lower values as the RE content increases, with the exception of Yb3+ doping, which did not affect the ferroelectric phase transition temperature. The phase transition behavior is explained using the standard soft mode model. Electronic paramagnetic resonance measurements showed the existence of Ti vacancies in the structure of RE-doped BCT23. Defects are created via charge compensation mechanisms due to the incorporation of elements with a different valence state relative to the ions of the pure BCT23 host. It is concluded that the Ti vacancies are responsible for the activation of the Raman mode at 840 cm-1, which is in agreement with lattice dynamics calculations. [ABSTRACT FROM AUTHOR]