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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.

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.