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Abstract: The stellarator Wendelstein 7-X (W7-X) is presently under construction at the Max-Planck-Institut für Plasmaphysik in Greifswald, Germany. The plasma density profile will be measured by two-colour interferometry where for each line of sight through the plasma the phase shifts of two far-infrared laser beams are compared. Due to the 3D shape of the superconducting coils in W7-X, opposite ports are not available. Instead, corner cube retro-reflectors (CCR) will be incorporated in the plasma vessel heat shield that reflect the beams back to the entrance window and diagnostic. This requires high accuracy of the reflecting surfaces which will be subjected to thermal loads from plasma radiation and therefore be heated up, displaced and deformed during operation. ANSYS is used to perform coupled thermo-mechanical analyses of the CCR, including plasma radiation, thermal conduction, and radiation between all parts. The resulting displacements provide the inputs to MATLAB routines which then yield local deformations, curvature radii, and tilting of the reflecting surfaces. This information is used to optimize the design of the CCR and their fixations. [Copyright &y& Elsevier]

Abstract: The Electron Cyclotron Emission diagnostic will be the main tool for the measurement of the electron temperature profile in the stellarator Wendelstein 7-X presently under construction in Greifswald, Germany. Design criteria and constraints for the ECE diagnostic are discussed. The resulting set-up is introduced with respect to the line of sight and the in-vessel optics. The 32-channel heterodyne radiometer system already used at the predecessor experiment Wendelstein 7-AS is adapted to the conditions at Wendelstein 7-X. [Copyright &y& Elsevier]

Background: Besides modern virus-screening methods, the avoidance of transfusion transmission of viral diseases is based on the best possible selection of healthy donors. Unfortunately, most of the relevant behavior-related risk factors are not accessible to objective verification. Drug screening can be used to validate a defined section of donor statements. It may be assumed that donors who conceal drug consumption may also conceal other relevant risk factors., Study Design and Methods: Hair and urine samples from 186 young potential donors who denied having consumed drugs were investigated by gas chromatography with mass selective detection and a urine fluorescence polarization immunoassay for cannabinoids, amphetamine and amphetamine derivatives, cocaine, and opiates., Results: Ten potential donors with 14 positive results on hair and urine analyses (6x cannabinoids, 4x cocaine, 1x opiates, 3x dihydrocodeine) could be identified in the population investigated., Conclusions: The donor history is not adequate for identifying potential donors with risk factors. Deliberately false statements concerning risk factors are a clear breach of trust between the blood bank and potential donors. These unreliable donors represent an incalculable risk for the transfusion recipient. Therefore, it is appropriate to validate donor statements about drug consumption by random hair and urine analyses and to exclude from the donor pool all persons revealed as drug users.