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Background: Dialysis and kidney transplant patients are vulnerable populations for COVID-19 related disease and mortality. Methods: We conducted a prospective study exploring the eight week time course of specific cellular (interferon-I³ release assay and flow cytometry) or/and humoral immune responses (ELISA) to SARS-CoV-2 boost vaccination in more than 3100 participants including medical personnel, dialysis patients and kidney transplant recipients using mRNA vaccines BNT162b2 or mRNA-1273. Results: SARS-CoV-2-vaccination induced seroconversion efficacy in dialysis patients was similar to medical personnel (> 95%), but markedly impaired in kidney transplant recipients (42%). T-cellular immunity largely mimicked humoral results. Major risk factors of seroconversion failure were immunosuppressive drug number and type (belatacept, MMF-MPA, calcineurin-inhibitors) as well as vaccine type (BNT162b2 mRNA). Seroconversion rates induced by mRNA-1273 compared to BNT162b2 vaccine were 97% to 88% (p

In recent years, a wide range of generalized barycentric coordinates has been suggested. However, all of them lack control over derivatives. We show how the notion of barycentric coordinates can be extended to specify derivatives at control points. This is also known as Hermite interpolation. We introduce a method to modify existing barycentric coordinates to higher order barycentric coordinates and demonstrate, using higher order mean value coordinates, that our method, although conceptually simple and easy to implement, can be used to give easy and intuitive control at interactive frame rates over local space deformations such as rotations.

The computation of the curvature of smooth surfaces has a long history in differential geometry and is essential for many geometric modeling applications such as feature detection. We present a novel approach to calculate the mean curvature from arbitrary normal curvatures. Then, we demonstrate how the same method can be used to obtain new formulae to compute the Gaussian curvature and the curvature tensor. The idea is to compute the curvature integrals by a weighted sum by making use of the periodic structure of the normal curvatures to make the quadratures exact. Finally, we derive an approximation formula for the curvature of discrete data like meshes and show its convergence if quadratically converging normals are available.

Room-temperature electronic properties of semiconductors, especially in the case of higher charge densities, are commonly discussed in terms of single-particle excitations -- free electrons and holes. Many-particle effects, such as the formation of excitons (Coulomb-bound electron-hole pairs), are usually seen as low-temperature and low-density phenomena. In this paper, using ultrafast terahertz and photoluminescence measurements, the authors find that under certain conditions typical for wide-band-gap semiconductors, the radiative excitons can be efficiently formed at high charge density and at room temperature. This effect is believed to contribute to the extraordinarily high quantum efficiency of group III nitride light emitters.

We compare radiative and nonradiative recombination in polar and nonpolar GaInN/GaN quantum wells and demonstrate that purely radiative recombination can be achieved even at room temperature. The radiative recombination is due to free excitons, which partially dissociate at elevated temperatures. Nonradiative recombination is strongly inhibited in the polar case but not in the nonpolar case.