Wire arc additive manufacturing (WAAM) is an additive manufacturing process based on gas metal arc welding. It allows the fabrication of large-volume metal components by the controlled deposition and stacking of weld beads. Next to the near-net-shape manufacturing of metal components, WAAM is also applied in the local reinforcement of structural parts, such as shell geometries.
View Article and Find Full Text PDFAn unusual high number of girls were referred to our paediatric endocrine clinic with suspected precocious puberty (PP) since the beginning of the COVID-19 pandemic. We analysed our data and initiated a survey among German paediatric endocrinologists.At our centre, less than 10 patients were diagnosed of PP annually between 2015 and 2019.
View Article and Find Full Text PDFAdditive manufacturing, in particular the powder bed fusion of metals using a laser beam, has a wide range of possible technical applications. Especially for safety-critical applications, a quality assurance of the components is indispensable. However, time-consuming and costly quality assurance measures, such as computer tomography, represent a barrier for further industrial spreading.
View Article and Find Full Text PDFWe report a measurement of the D^{0} and D^{+} lifetimes using D^{0}→K^{-}π^{+} and D^{+}→K^{-}π^{+}π^{+} decays reconstructed in e^{+}e^{-}→cc[over ¯] data recorded by the Belle II experiment at the SuperKEKB asymmetric-energy e^{+}e^{-} collider. The data, collected at center-of-mass energies at or near the ϒ(4S) resonance, correspond to an integrated luminosity of 72 fb^{-1}. The results, τ(D^{0})=410.
View Article and Find Full Text PDFA search for the flavor-changing neutral-current decay B^{+}→K^{+}νν[over ¯] is performed at the Belle II experiment at the SuperKEKB asymmetric energy electron-positron collider. The data sample corresponds to an integrated luminosity of 63 fb^{-1} collected at the ϒ(4S) resonance and a sample of 9 fb^{-1} collected at an energy 60 MeV below the resonance. Because the measurable decay signature involves only a single charged kaon, a novel measurement approach is used that exploits not only the properties of the B^{+}→K^{+}νν[over ¯] decay, but also the inclusive properties of the other B meson in the ϒ(4S)→BB[over ¯] event, to suppress the background from other B meson decays and light-quark pair production.
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