Abstract: Method for radiographic imaging, in particular for measuring the bone mineral density of an osseous body, this method involving an operation which consists in determining the value of a composite index using, on the one hand, digitized radiological data, and, on the other hand, a three-dimensional generic model of said osseous body.

Abstract: Method for radiographic imaging, in particular for measuring the bone mineral density of an osseous body, this method involving an operation which consists in determining the value of a composite index using, on the one hand, digitized radiological data, and, on the other hand, a three-dimensional generic model of said osseous body.

Abstract: A method of imaging by means of ionizing radiation in which a first measurement f1 is performed by integrating a detection signal generated by each detection cell of an ionizing radiation detector while simultaneously making a second measurement f2 by counting ionizing rays, and then an estimate of the flux is calculated, in particular by using the formula f=&agr;·f1+(1−&agr;)·f2 where &agr; is an increasing function over the range 0 to 1 of a first estimate fe of the flux f, which first estimate is established as a function of at least one of the first and second measurements f1 and f2.

Abstract: This is a method of generating a plurality of images of a substrate from radioactive radiation coming from a plurality of radioactive tracers contained in the substrate. To this end, data representing the different detection signals generated by a detector are memorised, individually for each radioactive emission detected during a certain observation period, then statistical processing of these data is carried out in such a way as to estimate the images of the different tracers which correspond best to the set of memorised data.

Abstract: This detector comprises a gas chamber (2) containing plane electrodes (4, 6, 8) delimiting conversion (C) and amplification (A) gaps. One of the electrodes is perforated with holes (18) and forms the detector cathode (6). The distance between the detector cathode and the anode (8) is less than 500 .mu.m. The intensity of the electric field in the amplification gap is ten times higher than the intensity of the electric field in the conversion gap. Application in particle physics, medicine, biology.

Abstract: A device for forming images of ionizing particles through single-dimensional electrophoresis provided with a multi-wire proportional chamber. The chamber filled with a gas is of asymmetric structure and is formed successively by an entry window for the particles, taken to a negative potential, a multi-wire anode electrode, taken to a potential positive with respect to a reference potential, and a cathode electrode which is placed in the vicinity of the anode electrode. The cathode electrode, which is taken to the reference potential, is formed by a network of parallel electrically conducting strips. Detection of the position of impact of the ionizing particle along the pitch of the network is performed by induction of a delayed electric pulse caused by an avalanche of the ionization electrons issuing from the ionizing particle in the region of the strip situated in line with the impact by the particle in the chamber, the reference time being that of the ionization electrons close to the wires.

Abstract: A method and device are disclosed for determining the distribution of the .beta. rays emerging from a surface. The device comprises an enclosure (3) filled with a gas mixture having a first preamplification chamber (6) between two grids (9 and 10), a second transfer chamber (7) between two grids (10 and (11) and a third multiplication chamber (8) between two grids (11 and 12); as well as three DC voltage sources (13, 14 15); and an impeding assembly (22, 23, 17, 18, 19, 20 and 21).