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Lens-based water-window X-ray microscopy allows two- and three-dimensional (2D and 3D) imaging of intact unstained cells in their near-native state with unprecedented contrast and resolution. Cryofixation is essential to avoid radiation damage to the sample. Present cryo X-ray microscopes rely on synchrotron radiation sources, thereby limiting the accessibility for a wider community of biologists. In the present paper we demonstrate water-window cryo X-ray microscopy with a laboratory-source-based arrangement. The microscope relies on a lambda = 2.48-nm liquid-jet high-brightness laser-plasma source, normal-incidence multilayer condenser optics, 30-nm zone-plate optics, and a cryo sample chamber. We demonstrate 2D imaging of test patterns, and intact unstained yeast, protozoan parasites and mammalian cells. Overview 3D information is obtained by stereo imaging while complete 3D microscopy is provided by full tomographic reconstruction. The laboratory microscope image quality approaches that of the synchrotron microscopes, but with longer exposure times. The experimental image quality is analyzed from a numerical wave-propagation model of the imaging system and a path to reach synchrotron-like exposure times in laboratory microscopy is outlined.

The alkaline electrolyzer industry is facing the imminent necessity of replacing the asbestos diaphragms with a separator made of a new environmentally friendly material. The influence of a diaphragm's material and porosity on the ionic conductivity was studied for asbestos, zirconium dioxide, wollastonite and olivine diaphragms. Developed electrochemical impedance spectroscopy (EIS) set-up with four-electrode cell offers the possibility for an accurate measurement of diaphragms’ ionic conductivity and enables its correlation to the materials porosity and tortuosity. The ion conductivity of investigated diaphragms approaches zero value for total porosities below 20% and increases when increasing porosities in agreement with Archie's law.

We describe the fabrication and evaluation of platinum zone plates for 5-12 kV X-ray imaging and focusing. These nano-scale circular periodic structures are fabricated by filling an e-beam generated mold with Pt in an electroplating process. The plating recipe is described. The resulting zone plates, having outer zone widths of 100 and 50 nm, show good uniformity and high aspect ratio. Their diffraction efficiencies are 50-70% of the theoretical, as measured at the European Synchrotron Radiation Facility. Platinum shows promise to become an attractive alternative to present hard X-ray zone plate materials due to its nano-structuring properties and the potential for zone-plate operation at higher temperatures.

Solid oxide electrolyser cells (SOECs) have great potential for efficient and economical production of hydrogen fuel. Element diffusion between the Ni-cermet electrode and the metal substrate of metal supported cells (MSC) is a known problem in fuel cell and electrolysis technology. In order to hinder this unintentional mass transport, different ceramic diffusion barrier layers (DBLs) are included in recent cell design concepts. This paper is based on wavelength dispersive X-ray fluorescence investigations of different SOEC and focuses on Fe, Cr and Ni diffusion between the metal grains of the cathode and the metal substrate. Due to the low detection limits and therefore high analytical sensitivity, wavelength dispersive electron probe microanalysis (EPMA) provides a precise method to determine element distribution, absolute element concentration and changes between the reference material and aged cells on a microstructural level by element mappings and concentration profiles. The results of this work show considerable concentration gradients in the metal grains caused by mass exchange during cell operation. Diffusion can be inhibited significantly by integrating different ceramic DBLs of doped LaCrO₃-type or doped LaMnO₃-type perovskite, either by vacuum plasma spraying (VPS) or physical vapour deposition technique (PVD).

Die Gruppe der Melanoma-Antigene (MAGE) scheint in vielen malignen Tumoren eine wichtige Rolle zu spielen. Melanoma-Antigene werden in einer Vielzahl von malignen Geweben expremiert und kommen außer in Hoden und Plazenta nicht im Normalgewebe vor. So können diese tumorassoziierten Proteine als potentielle Ziele in der Immunotherapie gegen Karzinome Anwendung finden, da Sie von autologen zytotoxischen T Lymphozyten erkannt werden können.Ziel dieser Studie ist es das Vorkommen von MAGE-A3 in Tumoren der Kopf-Halsregion zu untersuchen.Die Identifikation von MAGE-A3 in Tumorgewebsproben wurde mittels Reverser Transkription mit anschließender Polymerasekettenreaktion (RT-PCR) und Immunfluoreszenz durchgeführt. Von den 40 untersuchten Plattenepithelkarzinomen expremierten 23 MAGE A3. Die Präsenz des Antigens korrelierte weder mit dem Alter noch dem Tumorstadium der jeweiligen Patienten. Eine leichte Korrelation der Präsenz des Antigens mit der Tumorlage scheint in diesen 40 Proben jedoch vorzuliegen.Die Ergebnisse der RT-PCR konnten jeweils mittels Immunfluoreszenz verifiziert werden. Eine potentielle Immuntherapie gegen MAGE-A3 könnte so vielleicht auch in Tumoren der Kopf-Halsregion in Zukunft denkbar sein