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This study investigated the accuracy, drift, and clinical usefulness of a new optical transcutaneous oxygen tension (tcPO 2) measuring technique, combined with a conventional electrochemical transcutaneous carbon dioxide (tcPCO 2) measurement and reflectance pulse oximetry in the novel transcutaneous OxiVenT™ Sensor. In vitro gas studies were performed to measure accuracy and drift of tcPO 2 and tcPCO 2. Clinical usefulness for tcPO 2 and tcPCO 2 monitoring was assessed in neonates. In healthy adult volunteers, measured oxygen saturation values (SpO 2) were compared with arterially sampled oxygen saturation values (SaO 2) during controlled hypoxemia. In vitro correlation and agreement with gas mixtures of tcPO 2 (r = 0.999, bias 3.0 mm Hg, limits of agreement − 6.6 to 4.9 mm Hg) and tcPCO 2 (r = 0.999, bias 0.8 mm Hg, limits of agreement − 0.7 to 2.2 mm Hg) were excellent. In vitro drift was negligible for tcPO 2 (0.30 (0.63 SD) mm Hg/24 h) and highly acceptable for tcPCO 2 (− 2.53 (1.04 SD) mm Hg/12 h). Clinical use in neonates showed good usability and feasibility. SpO 2-SaO 2 correlation (r = 0.979) and agreement (bias 0.13%, limits of agreement − 3.95 to 4.21%) in healthy adult volunteers were excellent. The investigated combined tcPO 2 , tcPCO 2 , and SpO 2 sensor with a new oxygen fluorescence quenching technique is clinically usable and provides good overall accuracy and negligible tcPO 2 drift. Accurate and low-drift tcPO 2 monitoring offers improved measurement validity for long-term monitoring of blood and tissue oxygenation. Keywords Transcutaneous. tcPO 2. tcPCO 2. Oxygen. Fluorescence quenching * Willem van Weteringen

We report high-resolution angle-resolved photoemission experiments on epitaxial thin films of different rare-earth (RE) dihydrides ͑RE= Gd, La͒ and of YH 2 and ScH 2 . It is found through ab initio calculations and confirmed by Fermi surface mapping that the electronic structure becomes very similar upon hydrogenation, rendering the studied dihydrides isoelectronic. We propose that the dihydride phase acts as a common precursor state for the formation of the insulating trihydride phase. For states with higher binding energies (which exhibit considerable H character) the agreement between calculation and measurement is less convincing. Independent of the difficulties to describe these hydrogen related states, we note in the comparison between experiment and calculation a very convincing description of the Fermi surface for the dihydrides. Therefore we trace the apparent inability of density, functional theory to describe the hygrogenation up to the trihydride phase to an insufficient description of hydrogen states in general and, in particular, involving octahedral sites.

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We present a detailed high-resolution angle-resolved photoemission study of the electronic band structure of the room-temperature quasicommensurate charge-density-wave phase of 1T-TaS 2 . In particular, we show that no crossings of the Fermi level are visible in the complete Brillouin zone, indicating that an electron-electron correlation-induced pseudogap in the Ta 5d derived band exists already above the Mott localization-induced transition at 180 K. Moreover, we find that the electronic structure is governed by at least two quasiparticle peaks, which can be assigned to electrons from starlike shells of Ta atoms within the distorted crystal lattice. These peaks show quasilocalized ͑dispersionless͒ behavior in parts of the Brillouin zone where the one-particle band is unoccupied and they follow the one-particle dispersion in the occupied part. In order to address the question of possible Fermi-surface ͑FS͒ nesting, we scanned the remaining remnant FS and found regions with a considerable decrease of spectral weight. However, we find no clear evidence for FS nesting.