Nanostructure of a cold drawn tempered martensitic steel

The carbon atom distribution in a tempered martensitic steel processed by cold drawing was investigated with a three-dimensional atom probe. Data clearly show that cementite starts to decompose at the early stage of deformation. This indicates that the driving force of cementite decomposition during plastic deformation is not related to a strong increase of the interfacial energy. Carbon atmospheres were also analysed. They probably result from pipe diffusion of carbon atoms along dislocations pined by Fe3C carbides.Comment: 12 page

An automatic virtual patient reconstruction from CT-scans for hepatic surgical planning

International audiencePROBLEM/BACKGROUND: In order to help hepatic surgical planning we perfected automatic 3D reconstruction of patients from conventional CT-scan, and interactive visualization and virtual resection tools. TOOLS AND METHODS: From a conventional abdominal CT-scan, we have developed several methods allowing the automatic 3D reconstruction of skin, bones, kidneys, lung, liver, hepatic lesions, and vessels. These methods are based on deformable modeling or thresholding algorithms followed by the application of mathematical morphological operators. From these anatomical and pathological models, we have developed a new framework for translating anatomical knowledge into geometrical and topological constraints. More precisely, our approach allows to automatically delineate the hepatic and portal veins but also to label the portal vein and finally to build an anatomical segmentation of the liver based on Couinaud definition which is currently used by surgeons all over the world. Finally, we have developed a user friendly interface for the 3D visualization of anatomical and pathological structures, the accurate evaluation of volumes and distances and for the virtual hepatic resection along a user-defined cutting plane. RESULTS: A validation study on a 30 patients database gives 2 mm of precision for liver delineation and less than 1 mm for all other anatomical and pathological structures delineation. An in vivo validation performed during surgery also showed that anatomical segmentation is more precise than the delineation performed by a surgeon based on external landmarks. This surgery planning system has been routinely used by our medical partner, and this has resulted in an improvement of the planning and performance of hepatic surgery procedures. CONCLUSION: We have developed new tools for hepatic surgical planning allowing a better surgery through an automatic delineation and visualization of anatomical and pathological structures. These tools represent a first step towards the development of an augmented reality system combined with computer assisted tele-robotical surgery

Nanostructure of a cold drawn tempered martensitic steel

12 pagesThe carbon atom distribution in a tempered martensitic steel processed by cold drawing was investigated with a three-dimensional atom probe. Data clearly show that cementite starts to decompose at the early stage of deformation. This indicates that the driving force of cementite decomposition during plastic deformation is not related to a strong increase of the interfacial energy. Carbon atmospheres were also analysed. They probably result from pipe diffusion of carbon atoms along dislocations pined by Fe3C carbides

Crystallization of (±)-Modafinil in Gel: Access to Form I, Form III, and Twins

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Smoothness and degrees of freedom restrictions when using SPM 99

In NeuroImage 13(6 supplement 1):259International audienceno abstrac

Crystallization of (±)-Modafinil in Gel: Access to Form I, Form III, and Twins

International audienc

Comparison at the microscopic scale of mixed fatty acid-protein Langmuir-Blodgett films resulting from horizontal or vertical transfer

Mixed Langmuir films in which behenic acid and glucose oxidase are associated have been transferred by vertical or horizontal lifting methods onto pyrolytic graphite. The resulting films have been compared by scanning electron microscopy and by scanning force microscopy. The structures observed at the microscopic scale are different for the two transfer techniques in terms of homogeneity, dimensions and orientations. At a nanoscopic scale however, the organization of enzyme molecules is quite analogous in both cases.Des films mixtes de Langmuir associant acide béhénique et glucose oxydase ont été transférés par des techniques de transfert horizontal ou de transfert vertical sur graphite pyrolytique. La structure de ces films a été comparée par microscopie électronique à balayage et par microscopie à force atomique aux échelles microscopique et nanoscopique. Les structures observées à l'échelle du micromètre sont assez différentes pour les deux types de transfert (homogénéité, tailles caractéristiques, orientations). L'arrangement des molécules d'enzyme est toutefois comparable à l'échelle submicromètrique dans les deux cas

Incorporation of a Hydrophobic Antibacterial Peptide into Amphiphilic Polyelectrolyte Multilayers: A Bioinspired Approach to Prepare Biocidal Thin Coatings

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Une étude TEMP d'activation mnésique réalisée grâce à des recalages d'images 3D

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SPECT memory activation studies thanks to non-rigid automated 3D image registration

International audienceno abstrac