HREM of the [111] surfaces of iron oxide nanoparticles.

Mixed phase Fe3O4-gamma-Fe2O3 (magnetite-maghemite) iron oxide nanoparticles have been fabricated by colloidal routes. HRTEM/HRSTEM images of the nanoparticles show the presence of [111] facets that terminate with enhanced contrast, which is shown to be caused by the presence of additional cations at the edges of the nanoparticles. HRTEM images were taken on a FEI CM200 FEGTEM, a JEOL 3100 with a LaB6 source, and a double aberration corrected JEOL-JEM 2200FS FEGTEM. The enhanced contrast effect was observed on the [111] surface atomic layers resolved using each machine. HRSTEM images, taken on an aberration corrected STEM, resolved enhanced contrast at specific surface sites. Exit wave reconstruction was also carried out on focal series taken on a double aberration corrected JEOL-JEM 2200FS and showed similar highly resolved enhanced contrast at specific surface cation sites. It is apparent that additional cations are occupying the [111] terminating layers of these nanoparticle surfaces. The use of different microscopes and techniques in this paper provides strong evidence that the enhanced contrast is a real effect and not an effect caused by microscope aberrations.

An approach to the systematic distortion correction in aberration-corrected HAADF images.

Systematic distortion has been analysed in high-angle annular dark-field (HAADF) images which may be caused by electrical interference. Strain mapping techniques have been applied to a strain-free GaAs substrate in order to provide a broad analysis of the influence of this distortion on the determination of local strain in the heterostructure. We have developed a methodology for estimating the systematic distortion, and we correct the original images by using an algorithm that removes this systematic distortion.

[Do physicians know if their patients are satisfied? A study in general practice carried out by medical students]. / Vet legen om pasienten er tilfreds? En studentundersøkelse utført i allmennpraksis.

A doctor's ability to assess to what degree his patients are satisfied may indicate how well the patient and the doctor communicate. The main intention of this study was to evaluate the doctor's ability to register a patient's level of satisfaction after a consultation. 19 doctors from six medical centres in Eastern Norway participated. In 50% of the 216 consultations the doctors were able to state exactly how satisfied the patients were. In most of the cases with a mismatch between the doctor's and his patient's ratings the patients were more satisfied than the doctors realized. In some of these cases, however, the doctors failed to observe that the patients were dissatisfied. Male doctors were able to state the patients' level of satisfaction more accurately than female doctors were. Doctors with more experience were also more accurate in their assessments. The method of research used in this area can be problematic. A more reliable and valid questionnaire should be developed.