This letter is concerned with imaging a 3-D scene from a set of 2-D laser images of backscattered intensity without prior knowledge. The interaction between an electromagnetic wave and a medium can be understood and modeled in different ways. In the configuration considered here, the interactions result in a 3-D projection of the scene. After inspection in the measured signal, the reflection data appear as a sum of point spread functions with or without angular limitations. The approach proposed here consists thus in considering reflection data as an incomplete data set of Radon kind used in conventional computerized tomography. Under this approximation, reconstruction techniques, such as the well-known filtered back projection or the Feldkamp algorithm, can be exploited. The advantage of this approach is to provide isosurfacic reconstructions of the scene from reflective data performed with real-time computation times and without prior information. Simulation results on a real laser tomographic data set attest of the strength and of the relevancy of the proposed method.

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This paper deals with new optical non-conventional 3D laser imaging. Optical non-conventional imaging explores the advantages of laser imaging to form a three-dimensional image of the scene. 3D laser imaging can be used for threedimensional medical imaging, topography, surveillance, robotic vision because of ability to detect and recognize objects. In this paper, we present a 3D laser imaging for concealed object identification. The objective of this new 3D laser imaging is to provide the user a complete 3D reconstruction of the concealed object from available 2D data limited in number and with low representativeness. The 2D laser data used in this paper come from simulations that are based on the calculation of the laser interactions with the different interfaces of the scene of interest and from experimental results. We show the global 3D reconstruction procedures capable to separate objects from foliage and reconstruct a threedimensional image of the considered object. In this paper, we present examples of reconstruction and completion of three-dimensional images and we analyse the different parameters of the identification process such as resolution, the scenario of camouflage, noise impact and lacunarity degree.

Objectives Currently, two classes of oral anticoagulants are available in nursing home residents: vitamin K antagonists (VKA) and direct oral anticoagulants (DOAC). DOACs have a higher net clinical benefit than VKAs but DOACs are about 10 times more expensive than VKAs. The objective of our study was to assess and compare the overall costs of anti-coagulant strategy (VKA or DOAC), i.e., including drugs, laboratory costs and time spent in human capital (nurses and medical time) in nursing homes in France. Methods This was an observational, multicenter, prospective study including nine nursing homes in France. Among these nursing homes, 241 patients aged 75 years and older and treated with VKA (n = 140) or DOAC (n = 101) therapy accepted to participate in the study. Results During the 3-month follow-up period, the adjusted mean costs per patient were higher for VKA than DOACs for nurse care (€327 (57) vs. €154 (56), p<.0001) for general practitioner care (€297 (91) vs. €204 (91), p = 0.02), for coordinating physicians care (€13 (7) vs. €5 (7), p < 0.07), for laboratory tests (€23 (5) vs. €5 (5), p<.0001), but were lower for drug costs (€8 (3) vs. €165 (3), p<.0001). The average overall cost for 3 months per patient was €668 (140) with VKA vs. €533 (139) with DOAC (p = 0.02). Conclusion Our study showed that in nursing homes despite a higher drug cost, DOAC therapy is associated with a lower total cost and less time used by nurses and physicians for drug monitoring when compared to VKA.