Correlative light-electron fractography for fatigue striations characterization in metallic alloys.

The correlative light-electron fractography technique combines correlative microscopy concepts to the extended depth-from-focus reconstruction method, associating the reliable topographic information of 3-D maps from light microscopy ordered Z-stacks to the finest lateral resolution and large focus depth from scanning electron microscopy. Fatigue striations spacing analysis can be precisely measured, by correcting the mean surface tilting with the knowledge of local elevation data from elevation maps. This new technique aims to improve the accuracy of quantitative fractography in fatigue fracture investigations.

Correlative fractography: combining scanning electron microscopy and light microscopes for qualitative and quantitative analysis of fracture surfaces.

Correlative fractography is a new expression proposed here to describe a new method for the association between scanning electron microscopy (SEM) and light microscopy (LM) for the qualitative and quantitative analysis of fracture surfaces. This article presents a new method involving the fusion of one elevation map obtained by extended depth from focus reconstruction from LM with exactly the same area by SEM and associated techniques, as X-ray mapping. The true topographic information is perfectly associated to local fracture mechanisms with this new technique, presented here as an alternative to stereo-pair reconstruction for the investigation of fractured components. The great advantage of this technique resides in the possibility of combining any imaging methods associated with LM and SEM for the same observed field from fracture surface.

Extended depth from focus reconstruction using NIH ImageJ plugins: quality and resolution of elevation maps.

In this work, NIH ImageJ plugins for extended depth-from-focus reconstructions (EDFR) based on spatial domain operations were compared and tested for usage optimization. Also, some preprocessing solutions for light microscopy image stacks were evaluated, suggesting a general routine for the ImageJ user to get reliable elevation maps from grayscale image stacks. Two reflected light microscope image stacks were used to test the EDFR plugins: one bright-field image stack for the fracture of carbon-epoxy composite and its darkfield corresponding stack at same (x,y,z) spatial coordinates. Image quality analysis consisted of the comparison of signal-to-noise ratio and resolution parameters with the consistence of elevation maps, based on roughness and fractal measurements. Darkfield illumination contributed to enhance the homogeneity of images in stack and resulting height maps, reducing the influence of digital image processing choices on the dispersion of topographic measurements. The subtract background filter, as a preprocessing tool, contributed to produce sharper focused images. In general, the increasing of kernel size for EDFR spatial domain-based solutions will produce smooth height maps. Finally, this work has the main objective to establish suitable guidelines to generate elevation maps by light microscopy.

The effects of aging on biceps brachii muscle fibers: a morphometrical study from biopsies and autopsies.

OBJECTIVES: In order to study the morphology and size of muscle fibers, cross sections of biceps brachii samples from autopsies, up to 9 hours after death, and biopsies of 72 subjects were compared. The subjects aged 13 to 84 years in both sexes. METHODS: The samples obtained from autopsies (n=47) were from subjects with sudden death, or who died after acute disease without evidence of neuromuscular involvement. The biopsies (n=25) were from patients with symptoms suggestive of inflammatory or metabolic myopathy, not confirmed morphologically. The lesser diameter of muscle fibers was measured using the ATPase reaction. RESULTS: Morphological analysis showed that aging changes were present from the sixth decade in autopsies, and consisted of atrophy and/or type-grouping. The statistical models adjusted for females in both autopsies and biopsies were linear straight with no variation in fiber size with increasing age. The models adjusted for males in both groups were quadratic, indicating that age influenced the size of different type fibers. In males type 2 were larger than type 1 fibers, and than fibers in females. CONCLUSIONS: These values might be useful as controls, helping interpretation of changes in fiber size in samples obtained from biopsies and autopsies.

Absorçäo óssea podal bilateral progressiva associada a mal perfurante, osteomielite e septicemia fatal / Progressive feet bone absorption in association with \"Mal Perforant\", osteomyelitis and fatal sepsis

Os autores relatam um caso seguido no Hospital das Clínicas da Faculdade de Medicina de Ribeiräo Preto da Universidade de Säo Paulo apresentando uma síndrome trófica cutânea e óssea associada a uma síndrome sensitivo-motora, que evoluiu com mal perfurante plantar e osteomielite complicada com septicemia fatal

Patologia e a formaçäo do médico / Pathology and graduation in medicine

O presente artigo foi adaptado da aula inaugural para o curso de Patologia Geral da Faculdade de Medicina de Ribeiräo Preto (Universidade de Säo Paulo). O autor discorre sobre os objetivos da Patologia, os conceitos fundamentais de Patologia Geral, que permitem ao estudante compreender a extensäo deste ramo da Biologia, as relaçöes entre a Patologia e as Ciências Básicas da Medicina e a forma como ela fornece os substratos morfológico e funcional imprescindíveis ao exercício da Medicina Científica. O autor chama a atençäo para a autópsia como um instrumento essencial à formaçäo do estudante de medicina e à educaçäo continuada do médico. Finalmente comenta os aspectos profissionais da Patologia como Especialidade Médica