A simple pharmacokinetic model to explain the time course of [O-15]water in human whole blood after bolus injection is described. The model has been derived from measurements in twelve healthy volunteers who were measured repeatedly, resulting in 67 datasets, made in the context of PET blood flow studies. In contrast to traditional volume of distribution estimates of total body water (TBW) which rely on measurements after many hours, the model and data provide insights into the fast uptake components in the distribution of water in the body. Data fitting shows that the volume of distribution of fast exchanging tissues is 21 l, TBW was calculated to be 37 l. Monte Carlo simulation showed that the expected inaccuracy of determination of parameters due to unsystematic sources in the measurement data was around 5% for most parameters. Our data show that water extraction to tissue is somewhat higher than would be predicted from the tabulated values, probably because skeletal blood flow is sensitive to physiological status and environmental conditions. The study provides valuable reference data on the distribution and kinetics of water in man. Using the parameters and model from this study, reference input time-activity curves can be calculated, e.g. for the Monte Carlo study of error propagation in PET studies.

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ZnMgTe/ZnTe waveguide is a high potential electro‐optical device. Thick and high Mg composition cladding layers are required for high optical performance waveguides. However, adding Mg would increase the lattice mismatch between ZnMgTe and ZnTe which would cause dislocation defects and generate asperities at interfaces. In this article, influence of the lattice mismatch strain to the waveguide surface morphology was studied. Waveguide structures were prepared by molecular beam epitaxy. The surface morphologies were observed using atomic force microscope and propagation loss of the waveguides were studied. Total of 0.5–0.7 μm asperities were observed on the surface of waveguides with 20% of Mg composition and 1.2 μm of the total cladding layer thickness. The asperities on the surface became larger (1.0–1.2 μm) when the Mg composition increased to 40%. The propagation loss of the waveguide was suppressed to 7 dB by tuning the growth parameters and the resulting interface roughness.

ZnTe epilayers were grown on R ‐plane ($ 10 \bar 1 4 $) and S ‐plane ($ 10 \bar 1 1 $) sapphire substrates by molecular beam epitaxy, and the crystal orientation and the optical property were studied. The crystal orientation of ZnTe layers on sapphire substrates was studied using X‐ray diffraction pole figure measurements. It was confirmed that (111)‐oriented domains were formed on the R ‐plane as well as on the S ‐plane substrate. Layers grown on R ‐plane exhibited higher film quality. From the low‐temperature photoluminescence, emissions caused by ZnTe exciton were observed. (© 2016 WILEY‐VCH Verlag GmbH & Co. KGaA, Weinheim)