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The Vickers indentation zones in Al[sub 2]O[sub 3]-SiC-TiC ceramics were studied by scanning laser photoacoustic microscopy. It is shown that the method of photoacoustic microscopy with a piezoelectric detector is sensitive to external mechanical stresses. Variation of the photoacoustic response signal under the action of normal and tangent stresses in the vicinity of radial cracks was determined. The photoacoustic data can be used to estimate the stress intensity coefficients at the crack end. [ABSTRACT FROM AUTHOR]

The Vickers indentation zones in Al[sub 2]O[sub 3]-SiC-TiC ceramics were studied by scanning laser photodeflection and photoacoustic microscopy. The method of photoacoustic microscopy with piezoelectric detector (PAMPD) is sensitive to the internal stress distribution in the material. The effect of annealing on the PAMPD signal of the Al[sub 2]O[sub 3]-SiC-TiC ceramics was studied. An increase in the annealing time is accompanied by decrease in the PAMPD response from the vertices of radial cracks. [ABSTRACT FROM AUTHOR]

The in-plane resistance of single crystal non-magnetic Lu[sub x]Y[sub 1-x]Ni[sub 2]B[sub 2]C and magnetic Lu[sub x]Gd[sub 1-x]Ni[sub 2]B[sub 2]C samples as a function of the magnitude and direction of the magnetic field and temperature have been measured. The superconducting upper critical field H[sub c2](T) is anisotropic for both. A positive curvature in H[sub c2](T) near T[sub c](x) is clearly observed only for the non-magnetic impurity. At low temperature H[sub c2](T) for the sample with magnetic impurities is strongly reduced. Thermopower, thermal conductivity and resistivity as a function of temperature are also reported for Lu[sub x]Gd[sub 1-x]Ni[sub 2]B[sub 2]C. [ABSTRACT FROM AUTHOR]

Introduction: deep cannulation of the common bile duct is essential in endoscopic retrograde cholangiopancreatography (ERCP). However, cannulation is not possible in approximately 20 % of the cases with the usual techniques. Pre-cutting is an alternative that allows cannulation in difficult cases although its success is not guaranteed. Repeating the ERCP within three days of a failed pre-cut is an acceptable option., Objective: to determine if an ERCP performed three days after a failed pre-cut papillotomy allows the bile duct to be cannulated without increasing complication rates., Patients and Methods: patients who underwent an ERCP plus pre-cut were included, in whom the common bile duct could not be cannulated and who also underwent a new ERCP three days after the initial pre-cut. The primary objective was a successful biliary cannulation in the second ERCP and the secondary objective were the complications of the initial pre-cut., Results: forty patients with an average age of 65 years were identified and 57 % were male. The indications for ERCP were choledocholithiasis in 95 %, biliary fistula in 2.5 % and pancreatic neoplasia in 2.5 %. The ERCP was repeated three days later in 92.5 % of the cases and the biliary cannulation was successful in 78.3 %., Conclusions: a new ERCP performed within three days of a failed pre-cut is justifiable since it has a significant success rate. Bile duct cannulation is achieved in three out of four patients, with an acceptable percentage of complications.