CORRECTION OF AIRBORNE PUSHBROOM IMAGES ORIENTATION USING BUNDLE ADJUSTMENT OF FRAME IMAGES

To compute hyperspectral orthophotos of an area, one may proceed like for standard RGB orthophotos : equip an aircraft or a drone with the appropriate camera, a GPS and an Inertial Measurement Unit (IMU). The position and attitude data from the navigation sensors, together with the collected images, can be input to a bundle adjustment which refines the estimation of the parameters and allows to create 3D models or orthophotos of the scene. But most of the hyperspectral cameras are pushbrooms sensors : they acquire lines of pixels. The bundle adjustment identifies tie points (using their 2D neighbourhoods) between different images to stitch them together. This is impossible when the input images are lines. To get around this problem, we propose a method that can be used when both a frame RGB camera and a hyperspectral pushbroom camera are used during the same flight. We first use the bundle adjustment theory to obtain corrected navigation parameters for the RGB camera. Then, assuming a small boresight between the RGB camera and the navigation sensors, we can estimate this boresight as well as the corrected position and attitude parameters for the navigation sensors. Finally, supposing that the boresight between these sensors and the pushbroom camera is constant during the flight, we can retrieve it by matching manually corresponding pairs of points between the current projection and a reference. Comparison between the direct georeferencing and the georeferencing with our method on three flights performed during the Leman-Baikal project shows great improvement of the ground accuracy

Relationship between the structure of the flavone-C-glycosides of flax (Linum usitatissimum L.) and their biological activities

International audienceAtibiotics are one of the most important discoveries that have saved and is saving millions of lives in the world, but the emergence of resistant bacteria induces little or not effective for these synthetic products. In some situations the appearance of resistance prevents the treatment of infections caused by bacteria. The discovery of alternative antimicrobial agents has become urgently required.Many products of plant origin, in particular the class of flavonoids, exhibit antibacterial activity often associated with a high level of antioxidant power. Despite the many studies on this issue, the relationship between structure and function is currently poorly understood. To fill this gap, the biological activity of 12 flavone C-glycosides structurally close was studied. The structural variability of these compounds (derived from apigenin and luteolin) depends on the position and nature of the sugars, the number of hydroxyl groups and the presence of a methyl group.Thus, orientin, isoorientin, vitexin, isovitexin, swertisin, swertiajaponin, carlinoside, schaftoside, lucenin-1, lucenin-2, vicenin-1 and vicenin-2 were extracted from the aerial part of winter flax (Linum usitatissimum). The hydroalcoholic extract was purified by preparative HPLC and by the drowning-out crystallization method. Then, the control of the purity (greater than 99%) and the confirmation of the chemical structures were carried out by NMR and LC/MS. Antioxidant activity was tested by methods such as DPPH and FRAP and antimicrobial potential was assessed using common foodborne pathogens such as P. aeruginosa, E. coli, L. monocytogenes, L. innocua, S. arizonae, E. faecalis, S. aureus, B. subtilis

Relationship between the structure of the flavone-C-glycosides of flax (Linum usitatissimum L.) and their biological activities

International audienceAtibiotics are one of the most important discoveries that have saved and is saving millions of lives in the world, but the emergence of resistant bacteria induces little or not effective for these synthetic products. In some situations the appearance of resistance prevents the treatment of infections caused by bacteria. The discovery of alternative antimicrobial agents has become urgently required.Many products of plant origin, in particular the class of flavonoids, exhibit antibacterial activity often associated with a high level of antioxidant power. Despite the many studies on this issue, the relationship between structure and function is currently poorly understood. To fill this gap, the biological activity of 12 flavone C-glycosides structurally close was studied. The structural variability of these compounds (derived from apigenin and luteolin) depends on the position and nature of the sugars, the number of hydroxyl groups and the presence of a methyl group.Thus, orientin, isoorientin, vitexin, isovitexin, swertisin, swertiajaponin, carlinoside, schaftoside, lucenin-1, lucenin-2, vicenin-1 and vicenin-2 were extracted from the aerial part of winter flax (Linum usitatissimum). The hydroalcoholic extract was purified by preparative HPLC and by the drowning-out crystallization method. Then, the control of the purity (greater than 99%) and the confirmation of the chemical structures were carried out by NMR and LC/MS. Antioxidant activity was tested by methods such as DPPH and FRAP and antimicrobial potential was assessed using common foodborne pathogens such as P. aeruginosa, E. coli, L. monocytogenes, L. innocua, S. arizonae, E. faecalis, S. aureus, B. subtilis

Sacral nerve stimulation in faecal incontinence: position statement based on a collective experience.

International audienceOBJECTIVE: Since the first paper published by Matzel et al., in 1995, on the efficacy of sacral nerve stimulation (SNS) in patients with faecal incontinence, the indications, the contraindications, the stimulation technique and follow up of implanted patients have changed. The aim of this article was to provide a consensus opinion on the management of patients with faecal incontinence treated with SNS. METHOD: Recommendations were based on a critical review of the literature when available and on expert opinions in areas with insufficient evidence. RESULTS: We have reviewed the indications and contraindications, proposed an algorithm for patient management showing the place of SNS. The temporary test technique, the implantation technique, the patient follow up and the approach in case of treatment failure were discussed. CONCLUSION: We hope not only to provide a guide on patient management to clinical practitioners interested in SNS but also to harmonize our practices