Polytypism in mcalpineite: a study of natural and synthetic CuTeO.

Synthetic and naturally occurring forms of tricopper orthotellurate, CuTeO (the mineral mcalpineite) have been investigated by 3D electron diffraction (3D ED), X-ray powder diffraction (XRPD), Raman and infrared (IR) spectroscopic measurements. As a result of the diffraction analyses, CuTeO is shown to occur in two polytypes. The higher-symmetric CuTeO-1C polytype is cubic, space group Ia3, with a = 9.

Identification of Immune Activation Markers in the Early Onset of COVID-19 Infection.

This study aimed to determine the specific cytokine profile in peripheral blood during the early onset of COVID-19 infection. This was a cross-sectional exploratory, single center study. A total of 55 plasma samples were studied.

Nollmotzite, Mg[U(UO)OF]·4HO, the first natural uranium oxide containing fluorine.

Nollmotzite (IMA2017-100), Mg[U(UO)FO](HO), is a new uranium oxide fluoride mineral found in the Clara mine, Black Forest Mountains, Germany. Electron microprobe analysis provided the empirical formula (MgCu)[U(UO)OF][(HO)(OH)] based on three U and 15 O + F atoms per formula unit. Nollmotzite is monoclinic, space group Cm, with a = 7.

Emergent Momentum-Space Skyrmion Texture on the Surface of Topological Insulators.

The quantum anomalous Hall effect has been theoretically predicted and experimentally verified in magnetic topological insulators. In addition, the surface states of these materials exhibit a hedgehoglike "spin" texture in momentum space. Here, we apply the previously formulated low-energy model for BiSe, a parent compound for magnetic topological insulators, to a slab geometry in which an exchange field acts only within one of the surface layers.