The effect of stress anisotropy on the brittle failure of granite is investigated under uniaxial compression. Non‐standard asymmetric compression tests are performed on cores of Aue granite (diameter 52 mm, length 100 mm), in which 20 per cent of the core top surface remains unloaded. The edge of the asymmetric steel loading plate acts as a stress concentrator, from where a shear rupture is initiated. The propagation of the fracture‐related process zone from top to bottom of the core is mapped by microcrack‐induced acoustic emissions. Compared to standard uniaxial tests with symmetric loading, in the asymmetric tests both a greater quantity and more localized distributions of emission event hypocentres are observed. The maximum event density doubles for asymmetric (20 events per 10−6 m3) compared to symmetric tests. The cluster correlation coefficient, a measure of strain localization in the faulting process, reaches 0.15 for symmetric and 0.30 for asymmetric tests. The clustering of events, however, is found post‐failure only. Three different amplitudes are used to determine b‐values discussed as a possible failure precursor. Focal amplitudes determined at a 10 mm source distance and maximum amplitudes measured at eight piezoceramic sensors lead to b‐values that drop before rock failure. First‐pulse amplitudes automatically picked from emission wavelets show no anomaly. First‐motion polarity statistics of amplitudes indicate that a shear‐crack‐type radiation pattern is responsible for 70 per cent of the failure of granite, irrespective of stress boundary conditions. For type‐S events with an equal percentage of dilatational and compressional first motions, focal mechanisms are determined by fitting measured first‐pulse amplitudes to an assumed double‐couple radiation pattern. While hypocentres of large type‐S events align parallel to the later fracture plane, their fault plane solutions show no coherent pattern. Spatial views of fracture planes reconstructed from X‐ray computed tomograms reveal local small‐scale changes in fracture plane orientation. Nodal planes from average fault plane solutions of the microscopic acoustic emission events coincide with the overall orientation of the macroscopic fracture plane azimuth (strike angle) determined from thin sections and tomograms.

Because of its structure, the novel CGUARD EPS stent is characterized by a high flexibility combined with a high radial force and very good plaque coverage. These first clinical results demonstrate a very safe implantation behavior without any stroke up to 6 months after the procedure.

The first clinical results showed a safe implantation behavior without the occurrence of any ischemia. The structure of the new CASPER-RX stent creates an acceptable flexibility, low radial force, and high collapse pressure. The large foreshortening during implantation should be considered as well as the higher bending stiffness, especially when used in elongated carotid arteries.

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The treatment of choice in nondisplaced hook of hamate fractures is conservative, with lower arm splinting. Displaced fractures should be treated operatively, whereby excision of the fragment or open reduction and internal fixation are described. A hamulus ossis hamati fracture was verified in 14 patients (mean age, 42 years; range, 21 to 73 years) including 11 men and three women. In six patients (42.9 percent), conservative treatment was initiated immediately after trauma with a lower arm cast for 6 weeks, and eight patients (57.1 percent) were operated on primarily. In five patients (35.7 percent), the fragment was excised, and in three patients (21.4 percent), an open reduction and internal fixation was performed using a screw. In five of six patients treated conservatively, nonunion of the fracture with persisting clinical symptoms developed. All of those patients were treated operatively, whereby three patients underwent excision and two patients underwent screw fixation, which led to elimination of the symptoms. One patient was asymptomatic despite nonunion of the fracture and rejected surgery. All of the eight patients operated on primarily were asymptomatic 3 months after surgery. Therefore, the success rate of primary surgical treatment (eight of eight) was significantly higher compared with conservative treatment(one of six). Finally, all 14 patients were asymptomatic at late postoperative follow-up. The clinical outcome of patients with hook of hamate fractures treated conservatively was disappointing. Therefore, primary surgical treatment is recommended. In our patients, excision and open reduction and internal fixation led to comparable results.