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We studied the impact of soft ferromagnetic permalloy (Py) on the shielding currents in a strong-pinning superconductor—YBa2Cu3O7−δ with Ba2Y(Nb/Ta)O6 nano-precipitates—by means of scanning transmission x-ray microscopy. Typically and in particular when in the thin film limit, superconductor/ferromagnet (SC/FM) bilayers exhibit isotropic properties of the flux line ensemble at all temperatures. However, in elements with small aspect ratio a significant anisotropy in flux penetration is observed. We explain this effect by local in-plane fields arising from anisotropic magnetic stray fields originated by the ferromagnet. This leads to direction-dependent motion of magnetic vortices inside the SC/FM bilayer. Our results demonstrate that small variations of the magnetic properties can have huge impact on the superconductor.

Magnetic imaging of superconductors typically requires a soft-magnetic material placed on top of the superconductor to probe local magnetic fields. For reasonable results the influence of the magnet onto the superconductor has to be small. Thin YBCO films with soft-magnetic coatings are investigated using SQUID magnetometry. Detailed measurements of the magnetic moment as a function of temperature, magnetic field and time have been performed for different heterostructures. It is found that the modification of the superconducting transport in these heterostructures strongly depends on the magnetic and structural properties of the soft-magnetic material. This effect is especially pronounced for an inhomogeneous coating consisting of ferromagnetic nanoparticles.

Scanning transmission x-ray microscopy has been used to image electric currents in superconducting films at temperatures down to 20 K. We detect significant deviations from a regular current path driven by macroscopic geometrical constraints. The magnetic stray field of supercurrents in a thin YBaCuO film is mapped into a soft-magnetic coating of permalloy. The so-created local magnetization of the ferromagnetic film can be detected by dichroic absorption of polarized x rays. To enable high-quality measurements in transmission geometry, the whole heterostructure of ferromagnet, superconductor, and single-crystalline substrate has been thinned to an overall thickness of less than 1 \textmu{}m. With this technique, local supercurrents can be analyzed in a wide range of temperatures and magnetic fields. The less than 100 nm spatial resolution of the magnetic signal together with simultaneously obtained nanostructural data allow the correlation of local supercurrents with the micro- and nanostructure of the superconducting film.

Magneto-optical Kerr-effect (MOKE) measurements of superconducting films with soft-magnetic coatings are performed at low temperatures using a laser-based MOKE set-up. An elaborate measurement scheme with internal reference allows the quantitative comparison of the temperature dependent Kerr-amplitude with the magnetic field generated by supercurrents. For this purpose, an amorphous CoFeB thin film exhibiting a large Kerr-signal is deposited directly on top of the YBCO superconductor acting as field sensing layer. It is shown that the resulting magnetic hysteresis loops of the soft-magnetic film can be used to reconstruct the electric properties of the superconductor.

Die Beurteilung der Operabilitat eines Patienten erfordert ein sorgfaltiges Abwagen von Befunden der Allgemeinuntersuchung und eine Prufung der respiratorischen Reserven. Dadurch werden bei Wahloperationen das Risiko der postoperativen Komplikationen vermindert und die Erfolgsaussichten verbessert. Differenzierte Methoden der Lungenfunktionsprufungen sollen bei Anzeichen einer Atemstorung vor jeder Oberbauch- und Thoraxoperation sowie bei respiratorisch gefahrdeten Patienten uber 60 Jahren zur Anwendung gelangen. Eine Vorbehandlung betrifft vor allem Patienten mit obstruktiver Ventilationsstorung und umfast eine antibronchitische Therapie mit Antibiotics, Aerosolen und Beatmungsinhalationen.

Ein Blutersatz mit stromafreier Haemoglobin-Losung last folgende Vorteile erwarten: 1. Im Gegensatz zu den ublichen Plasmaexpandern ist mit der Haemoglobin-Losung neben dem Volumenersatz auch ein Sauerstoff-Transport moglich. 2. Gegenuber Konservenblut hat die Haemoglobin-Losung den Vorteil einer blutgruppen-unabhangigen Ubertragbarkeit sowie den Vorteil der Hepatitis-Sicherheit.

Im Berichtszeitraum vom Oktober 1970 bis Mai 1973 wurden auf der Beatmungsstation der Universitatskliniken Heidelberg, die unter anaesthesiologischer Leitung steht, 286 Patienten behandelt. Neben der Beatmungsstation existieren an unserer Klinik mehrere fachgebundene Intensiveinheiten sowie eine allgemeinchirurgische Wachstation. Unsere Patienten sind daher ein ausgewahltes Krankengut, bei welchem die respiratorische Insuffizienz im Vordergrund steht.