Joint Shape and Motion Estimation using Markovian Fields : Application to Multislice Computed Tomography Cardiac Imaging

We propose a method for joint surface and non-rigid motion estimation from three-dimensional dynamic sequences. Based on a surface-volume matching, it provides, from one first segmented surface, both motion and deformations of the object of interest along the whole sequence. A Markovian model, combined with a simulated annealing process, estimates the correspondences between the nodes of the surface mesh modeling the object of interest at one time and the voxels of the volume representing the object at the following time. The method has been applied to cardiac surface and motion extraction in Multislice Computed Tomography. Tests realized with simulated motion and on real data have provided promising results.Une méthode d'estimation conjointe de forme et de mouvement non rigide à partir de séquences temporelles tridimensionnelles est proposée. Reposant sur une mise en correspondance surface-volume, elle permet, à partir d'une première segmentation de l'objet d'intérêt, d'estimer le mouvement de l'objet et ses déformations sur toute la séquence temporelle d'observation. Une modélisation markovienne combinée à un algorithme de recuit simulé estime les correspondances entre les noeuds du maillage de surface modélisant l'objet à un instant et les voxels du volume représentant l'objet à l'instant suivant. La méthode a été appliquée à l'extraction de formes et de mouvements cardiaques en tomodensitométrie multibarrette. Les tests, réalisés à la fois avec des mouvements simulés et sur des données réelles, ont donné des résultats prometteurs

Structured Biotinylated Poly(3,4-Ethylenedioxypyrrole) Electrodes for Biochemical Applications

The immobilization of biotin on transducer surfaces is a very important step for the fabrication of biosensors for many applications (immunoassay, DNA-hybridization assays, targeted imaging). Biotinylated polypyrroles have been studied and tested but gave rise to problems of polymerization and stability due to the intrinsic properties of pyrrole. As an alternative, biotinylated pyrroles were often used in a copolymerization with pyrrole or with an amphiphilic pyrrole derivative in a copolymerization to reduce the problems due to the pyrrole substitution. To find a new strategy, this paper presents the homopolymerization, instead of the use of a copolymerization, by replacing pyrrole by 3,4-ethylenedioxypyrrole bearing biotinylated substituent. We report the synthesis, characterization and electrochemical properties of two biotinylated 3,4-ethylenedioxypyrroles differing by the length of the alkyl spacer (ethyl or dodecyl) as well as the characterization of the corresponding polymer films. We successfully show, by cyclic voltammetry, that these monomers polymerize perfectly and give relatively stable polymer films. The increase of the alkyl spacer improves the polymerization and increases the polymer stability. For the first time, we also studied the surface morphology of an electrodeposited biotinylated polymer. The electrodeposition of these biotinylated derivatives gave rise to the ability to modulate the surface microstructuration, which consists of microspheres or cauliflower-like microstructures according to the length of the alkyl spacer.JRC.I.4-Nanobioscience

Gravel bed-river morphodynamics and large wood budgeting

International audienc

Gravel bed-river morphodynamics and large wood budgeting

International audienc

Développement pour l'analyse de bilan ligneux à l'échelle d'un corridor fluvial : le cas de la rivière Saint-Jean en Gaspésie (Canada)

International audienc

Assessment of the annual dynamics of large woods along a 60 km semi-alluvial river section of the Gaspe Peninsula, Quebec, Canada, feedbacks from 3 years field surveys combined with airbone and ground images

International audienc

Des outils de gestion pour la dynamique des bois morts : le cas du corridor fluvial de la rivière Saint-Jean, Gaspé

International audienc

Développement pour l'analyse de bilan ligneux à l'échelle d'un corridor fluvial : le cas de la rivière Saint-Jean en Gaspésie (Canada)

International audienc

Des outils de gestion pour la dynamique des bois morts : le cas du corridor fluvial de la rivière Saint-Jean, Gaspé

International audienc

Assessment of the annual dynamics of large woods along a 60 km semi-alluvial river section of the Gaspe Peninsula, Quebec, Canada, feedbacks from 3 years field surveys combined with airbone and ground images

International audienc