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A considerable number of detailed investigations have been carried out on the deposition and characterisation of molybdenum and molybdenum-titanium-nitride films by employing a variety of techniques. However, very little is currently known about the effect of composition (N-2/Ar flow rate) on the corrosion properties of MoN and MoTiN thin films for aggressive ambient conditions. In this work, the electrochemical and corrosion behaviour of MoN and MoTiN thin films, produced by Physical Vapour Deposition (PVD) with different N2/Ar flow rates, has been investigated by Electrochemical Impedance Spectroscopy (EIS) in aerated alkaline chloride solution and compared with the behaviour of pure molybdenum in the same environment. Results obtained indicate that increasing nitrogen content in the film leads to a beneficial effect on the corrosion resistance, but results in decreased electrical conductivity of the film that may limit their application as back contact in photovoltaic modules.

International audience; The variability assessment of the rib bone mechanical properties during the growth process is still missing. These properties could not be obtained in vivo on children. Relationships have been obtained between Hounsfield Units from computed tomography (CT) and mechanical properties (e.g. for the cortical bone on adults). As a first step for investigation of the mechanical properties of child ribs, the aim of this study was to determine the Hounsfield Units variation of child ribs from CT‐scan data, by rib level, along the rib and within the rib sections. Twenty‐seven right ribs of levels 4, 6 and 9 were processed from 11 thoracic CT scans of children without bone lesions aged between 1 and 10 years. A first set of 10 equidistributed cross‐sections normal to the rib midline were extracted. Sixteen equally distributed elements defined 4 areas into the cortical band: internal, external, caudal and cranial. Within the rib sections, Hounsfield Units were found significantly higher in internal and external areas than in caudal and cranial. In a further step using calibrated CT scans, it would be possible to derive the mechanical properties of in vivo child ribs using bone density correlation with Hounsfield Units.

1 - Article; Ligart project aimed to propose a new generation of artificial ligament which can be considered as "bioactive" and "biointegrable" destined to be used in anterior cruciate ligament (ACL) reconstruction surgery of patients with knee ACL rupture frequently related to contact and pivoting sports. Such bioactive ligament will allow preventing hostile host response due to the presence of a bioactive polymer grafted on its surface. The LARS prosthetic ligament made of poly (ethylene terephtalate) is chemically grafted by a "bioactive" and "biomimetic" polymer, which will allow masking the synthetic origin of the material and controlling collagen secretion. fibroblasts proliferation and inflammatory response. The bioactive ligament can be considered as "biointegrated", i.e. integrated by the living system: it induces controlled fibroblast cell proliferation and colonization along the PET fibres of the joint part of the prosthetic ligament, ensure and/or steady appropriate mechanical behaviour of the ligament which can be compared to that of the biological ACL, decrease the inflammatory response and prevent acute synovites extensively described in the case of the first generation of synthetic ligament. Fifty-six sheep divided in two series devoted to the evaluation of (1) the biological response (histology, molecular biology, SEM) and (2) the biomechanical behaviour were implanted with bioactive polymer grafted or commercial ACL for 3 or 12 months. Results show that the grafting of PET ligament by the bioactive polymer sensitively improves the biological response at 3 and 12 months. Preclinical study in clog has started and experiments on human are scheduled in the next future.

A three-dimensional segmental analysis was performed on the stereoradiographic reconstructions of ten right thoracic scoliotic patients. From the quantitative model of the spine and pelvis, the vertebral and intervertebral orientations were computed pre and post operatively. These orientations allow to determine the apical and junctional zones of the high thoracic, thoracic and lumbar curves. The apical zone corresponds to the maximum of vertebral axial rotation. Pre operatively, the tendency was T7 for the thoracic transverse apex with 20 AE of axial rotation. The junctional zone corresponds to the maximum of vertebral lateral rotation and the maximum of intervertebral axial rotation. The tendency was T5 and T12 for the junctional vertebrae of the thoracic curve with, at both levels, 30 AE of vertebral lateral rotation and 10 AE of intervertebral axial rotation. The surgical correction obtained by in situ contouring technique was evaluated through these 3D orientations. The vertebral axial rotation at the high thoracic, thoracic and lumbar apex was corrected with respectively 52%, 60% and 60%.

Stereoradiography is a well known method to obtain 3D images of the spine and the thorax. The main algorithm used is the DLT, which is a very general one yielding to 11 implicit parameters per view. In order to calibrate the geometrical configuration of the stereoradiographic setup with this algorithm, there is a need of a wide calibrating object, leading to systems hard to use in clinical practice. The aim of this work was to modify the algorithm in order to simplify the calibration object. We used assumptions related to the specific case of stereoradiography, which reduced the problem of calibration to only 6 independent explicit parameters. A geometrical calibration performed plane by plane enabled to design a singular calibration object composed of steel balls along two vertical lines and three horizontal ones. A simulation of real configuration both for the previous method and the current algorithm associated to the singular calibrating object give for thirty 3D points a 2 RMS (95% confidence interval) error of reconstruction of respectively 0.6 and 0.3 mm. This study yielded to the transfer in clinics of two simplified systems of calibration which will be easier to use in clinical practice.