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Programming in high abstraction level can facilitate the development of digital signal processing systems. In the recent 20 years, high-level synthesis (HLS) has made significantly progress. This technique greatly benefits the R&D productivity of the Field Programmable Gate Array (FPGA) developments and helps for adding to the maintainability of the products by automating the C-to-RTL (register transfer language) conversion. However, due to the high complexity and computational intensity, image processing algorithms usually necessitate a higher abstraction environment than C-synthesis, and the current HLS tools do not have the ability of this kind. This paper presents a conception of very high-level synthesis method which allows fast prototyping and verifying the FPGA-based image processing designs in the MATLAB environment. We build a heterogeneous development flow by using currently available tool kits for verifying the proposed approach and evaluated it within two real-life applications. Experiment results demonstrate that it can effectively reduce the complexity of the development by automatically synthesizing the algorithm behavior from the user level into the low register transfer level and give play to the advantages of FPGA related to the other devices.

International audience; We designed stable and highly reproducible hydrogels by external unidirectional diffusion of Fe2+ ions into aqueous solutions of polygalacturonate (polyGal) chains. The Fe2+ ions act as cross-linkers between the Gal units in such a way that both the molar ratio R ([Fe2+]/[Galunits]=0.25) and the mesh size of the polyGal network at the local scale (zeta=75 +/- 5 angstrom) have constant values within the whole gel, as respectively determined by titration and Small Angle Neutron Scattering. From macroscopic point of view, there is a progressive decrease of polyGal concentration from the part of the gel formed in the early stages of the gelation process, which is homogeneous, transparent and whose Young modulus has a high value of similar to 10(5) Pa, up to the part of the gel formed in the late stages, which is heterogeneous, highly turbid and has a much lower Young modulus of similar to 10(3) Pa. Since the local organization of the polyGal chains remains identical all along the hydrogels, this macroscopic concentration gradient originates from the formation of heterogeneities at a mesoscopic length scale during the gelation process. In addition, X-ray Absorption Spectroscopy measurements remarkably reveal that Fe2+ ions keep their +II oxidation state in the whole gels once they have cross-linked the Gal units. These polyGal hydrogels thus protect iron against oxidation and could be used for iron fortification.

International audience; The aim of this study was to investigate the influence of the surface charge and coating of Superparamagnetic Iron Oxide Nanoparticles (SPIONs) on their in vitro and in vivo behaviors. Neutral and negatively-charged PEG-based SPIONs were synthesized and compared to Resovist (R), a carboxydextran-based SPION currently used in clinics. Their cytotoxicity, cell internalization, and potential as contrast agents for magnetic resonance imaging were assessed. Neutral pegylated SPIONs were internalized less readily by the reticuloendothelial system and showed a lower uptake by the liver, compared to negatively-charged SPIONs (with carboxydextran and PEG). These results suggested that the charge of functionalized SPIONs was more relevant for their biological interactions than the nature of their coating.