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Electric motors are ubiquitous on spacecraft and their smooth operation relies on the presence of naturally magnetic materials. The employment of conventional metal‐based magnets causes some inconveniences such as high values of specific gravity and the limited reproducibility of complicated geometries. The introduction of novel polymer‐based magnetic materials processed via additive manufacturing represents a brilliant answer to these needs. This paper describes the first‐time development of a polyether ether ketone‐magnetite (Fe3O4) soft magnetic composite. The material was prepared by adding 50 wt% magnetic microparticles to the polymeric matrix. The composite material was extruded in form of filaments and 3D printed via fused filament fabrication. The thermomechanical characterization demonstrated the stability of the material at both processing ad use temperatures, while the magnetic analysis reported a typical soft magnetic behavior with 25.7 A m2 kg−1 magnetization at saturation. The measured properties were employed as inputs for the finite element analysis of an axial flux brushless direct current electric motor, as a proof of concept. The simulation of the electromechanical behavior of the motor showed promising performance for the composite material, reaching the maximum deliverable torque of about 0.8 Nm (compliant to small power aerospace applications such as micro‐actuators and mini control moment gyroscopes) with weight savings up to 50%. [ABSTRACT FROM AUTHOR]

The article presents a case study of a 24-years-old man with a family history of sudden death was scheduled for sudden cardiac death screening at our Center after an episode of syncope. Topics include the alterations related to generation and/or conduction of action potentials in the cardiac tissue can result in the origin and propagation of cardiac arrhythmias, and the heritable mutations in genes that encode heart ion channels are the underlying cause of arrhythmias.

Introduction Methods Results Conclusion The dST‐Tiso is a newly proposed electrocardiographic (ECG) marker during Brugada (BrS) type I pattern, that predicts the likelihood of ventricular arrhythmia (VA) inducibility in patients with ajmaline‐induced pattern. The objective of this study was to validate the effectiveness of this criterion using an independent data set.Consecutive patients exhibiting a BrS type I ECG pattern following ajmaline administration underwent programmed ventricular stimulation (PVS). dST‐Tiso interval was measured in all patients and tested as a predictor for positive VA inducibility.Among 128 patients (median age 43 years, 59% male) with drug‐induced BrS type I ECG pattern who underwent PVS, 32 (25.0%) had VA inducibility that required defibrillation. Compared to noninducible subjects, those with positive PVS were more commonly male (81% vs. 51%, p = 0.003), had longer PQ (165 vs. 160 ms, p = 0.016) and dST‐Tiso (310 vs. 230 ms, p < 0.001) intervals, and shorter QT interval (412 vs. 420 ms, p = 0.022). When treated as a continuous variable, dST‐Tiso confirmed significant association with VA inducibility, with an adjusted odds ratio of 1.02 (95% confidence interval: 1.01–1.03, p < 0.001) for each 1 ms increase in duration. A dST‐Tiso interval >300 ms yielded a sensitivity of 75%, a specificity of 86%, and positive and negative predictive values of 69% and 91%, respectively.The validation of the model based on the dST‐Tiso interval >300 ms confirmed its high accuracy in predicting VA inducibility in drug‐induced BrS type I pattern. This straightforward ECG marker might be linked to the extent of the electrical substrate of the disease. [ABSTRACT FROM AUTHOR]