Les enjeux économiques de ľinterconnexion des réseaux

The network interconnection and its regulation consist in solving the following dilemma: increase competition and preserve the universal service through access charges, which symbolizes today institutional organization within the telecommunication industry. This paper presents some of the economic and social factors that drive the interconnection policies namely ona (open network architecture) in the United States, or onp (open network provision) in Europe. In the first section, we list some social and economical issues related to open network policies. In the second section, we study the different answers brought up by the regulator through alternative interconnection price formulas. In conclusion, we discuss the stakes and risks of interconnection, while the technological evolution of network introduces intelligent software in switching équipement and implements the tremendous abilities of the digital broadband networks.     

Digital Surface of Revolution with Hand-Drawn Generatrix

In this paper we present a simple method to create general 3D digital surfaces of revolution based on a 2D implicit curve of revolution (therefore not limited to a circle) and a hand-drawn generatrix. Our method can handle any sequence of Euclidean 2D points, which represents a curve, as generatrix. One can choose the topology of the surface that may have 1-tunnels, 0-tunnels or no tunnels with applications in 3D printing for instance. An online tool that illustrates the method is proposed.     

Natural Ligands of Porcine Olfactory Binding Proteins

Knowledge of endogenous ligands of olfactory binding proteins is a prerequisite for studying their role in odor and pheromone transduction. Here, we report the extraction, derivatization, and characterization by gas chromatography-mass spectrometry of the natural ligands of pig, Sus scrofa (L.), Von Ebner’s Gland protein (VEG) and odorant binding protein (OBP). We identified two isoforms (VEG1 and VEG2), which differed only by the linkage of an O-N-acetylglucosamine (O-GlcNac) group on VEG1. The natural ligands of VEG1 were characterized as two isomers of testosterone, whereas ligands of VEG2 and OBP were fatty acids or their derivatives. Our findings suggest that the binding specificity of VEG1 for steroids is governed by the presence of an O-GlcNac moiety on the protein. This specificity was confirmed by the binding of radiolabeled testosterone only by VEG1 in an in-gel binding assay. This is the first evidence for a post-translational modification in the process of odorant discrimination by olfactory binding proteins.     

Ellipsometry of reflected and scattered fields for the analysis of substrate optical quality

Specular ellipsometry is a well-known and efficient technique to characterize surfaces and coatings. This technique has been extended to the measurement of scattered light. We present an experimental setup, using a polarization modulator, which permits us to characterize transition layers and roughness without a calibration procedure. Experimental results are presented concerning transition layers for damage threshold applications and for rough surfaces or bulks.     

One Step Synthesis of Gold‐Loaded Radial Mesoporous Silica Nanospheres and Supported Lipid Bilayer Functionalization: Towards Bio‐Multifunctional Sensors

A simple synthetic route is developed to achieve gold functionalized radial mesoporous silica nanoparticles (Au‐MsNP) synthesized by a one step procedure fully compatible with basic conditions required for the preparation of monodispersed nanospheres. In a second step, Au‐MsNP particles have been coated with phospholipid bilayers in order to design an advanced biofunctional platform with the gold metallic nanoparticles previously grown into the pore channels and responsible for a plasmonic activity relevant for biosensing. The size of Au‐MsNP is checked by dynamic light scattering while zeta potential measurements reflect their surface charge. The particle morphology is characterized by transmission and scanning electron microscopy and the Si/Au ratios are obtained from energy dispersive X‐ray analysis. The textural properties of Au‐MsNP, specific surface area and pore size, are determined from N₂ adsorption. The supported bilayers are achieved from vesicles of different phospholipids incubated with Au‐MsNP particles. The coating efficiency is investigated by zeta potential and cryo‐ transmission electron microscopy. The plasmonic activities of bare Au‐MsNP particles and coated lipid bilayer Au‐MsNP platform are evidenced for two model systems: direct adsorption of bovine serum albumin and molecular recognition events between avidin molecules and biotin receptors integrated in the supported lipid bilayer.     

Fabrication and micromechanical characterization of polycrystalline diamond microcantilevers

The exceptional chemical, mechanical and thermal properties of diamond make this material the ideal choice for resonant MEMS. Micro-cantilevers designed for biochemical applications have been fabricated using CVD diamond. In this work, the mechanical properties of these cantilevers were investigated by two different techniques: bending test using a Contact Surface Profilometer and resonant test, using a Laser Doppler Vibrometer. The Young’s Modulus of diamond thin film was estimated by these two tests. For the resonance test, the estimated values are comprised between 930 and 1300 GPa while bending test gives values between 950 and 1030 GPa. The load–displacement characteristics and the fracture point (or ultimate stress) have also been investigated.     

Bimodal Detection of Proteins by 129Xe NMR and Fluorescence Spectroscopy

A full understanding of biological phenomena involves sensitive and noninvasive detection. Herein, we report the optimization of a probe for intracellular proteins that combines the advantages of fluorescence and hyperpolarized ¹²⁹Xe NMR spectroscopy detection. The fluorescence detection part is composed of six residues containing a tetracysteine tag (−CCXXCC−) genetically incorporated into the protein of interest and of a small organic molecule, CrAsH. CrAsH becomes fluorescent if it binds to the tetracysteine tag. The part of the biosensor that enables detection by means of ¹²⁹Xe NMR spectroscopy, which is linked to the CrAsH moiety by a spacer, is based on a cryptophane core that is fully suited to reversibly host xenon. Three different peptides, containing the tetracysteine tag and four organic biosensors of different stereochemistry, are benchmarked to propose the best couple that is fully suited for the in vitro detection of proteins.     

Spectral beam combining of a single-mode 980-nm laser array for pumping of erbium-doped fiber amplifiers

With a view to improve the power level and brightness of semiconductor pump lasers, we have resorted to a scalable implementation and achieved spectral beam combining through a low-quality-factor external cavity. For that purpose, a high-power single-mode laser array emitting up to 2.1 W at 3.2 A at 980 nm has been realized, which delivers 1.5 W in external cavity. A power of 0.66 W was finally coupled into the single-mode fiber, with a coupling efficiency of 44%. Pumping experiments of an erbium-doped fiber amplifier utilizing this laser have demonstrated efficiency and noise characteristics similar to what is usually obtained with conventional sources, with the noteworthy advantage of a lower gain excursion over the C-band.