Interaction vertex imaging (IVI) for carbon ion therapy monitoring: a feasibility study

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Real time monitoring of the Bragg-peak position in ion therapy by means of single photon detection

For real-time monitoring of the longitudinal position of the Bragg-peak during an ion therapy treatment, a novel non-invasive technique has been recently proposed that exploits the detection of prompt -rays issued from nuclear fragmentation. Two series of experiments have been performed at the GANIL and GSI facilities with 95 MeV/u and 305 MeV/u 12C6+ ion beams stopped in PMMA and water phantoms. In both experiments a clear correlation was obtained between the carbon ion range and the prompt photon profile. Additionally, an extensive study has been performed to investigate whether a prompt neutron component may be correlated with the carbon ion range. No such correlation was found. The present paper demonstrates that a collimated set-up can be used to detect single photons by means of time-of-flight measurements, at those high energies typical for ion therapy. Moreover, the applicability of the technique both at cyclotron and synchrotron facilities is shown. It is concluded that the detected photon count rates provide sufficiently high statistics to allow real-time control of the longitudinal position of the Bragg-peak under clinical conditions

Nouvelles méthodes d'imagerie en ligne pour le contrôle de l'irradiation en hadronthérapie

International audienc

[Computerized tomography-guided neurolytic block of the splanchnic nerve].

CT-guided neurolytic splanchnic nerve block is a technique for relieving abdominal cancer pain; the goal is the alcoholic neurolytic interruption of the sensitive structures in retroperitoneal space. CT yields accurate anatomical detailing and the course for needle placement and alcohol spread. January, 1993, to July, 1996, twenty-one bilateral splanchnic nerve blocks were performed through the posterior access. Forty-eight hours after alcoholization, 14 patients (66\%) had complete pain regression; 52\% of the patients needed no analgesics for 6 to 54 days and only 9 patients (42\%) needed another low opioid therapy. Complications included hypotension and diarrhea in all cases. One had a cardiac arrest and died 8 days after the procedure. There were no other complications. The whole procedure usually lasted 60 min (range: 45 to 90 min). Splanchnic nerve neurolysis is a useful treatment in the patients with severe chronic abdominal pain. It is used as a second line treatment when large lesions change celiac anatomy and complicate the percutaneous block of the celiac plexus

Low evidence for extra-pair fertilizations in two reintroduced populations of Griffon Vulture (Gyps fulvus)

The Griffon Vulture (Gyps fulvus) is considered to be socially monogamous. However, extra-pair fertilizations are suspected due to observations of extra-pair copulations in some populations. We performed parentage studies based on ten polymorphic microsatellite markers in two reintroduced colonies of Griffon Vulture. Out of 40 genotyped chicks, we found eight chicks whose genotypes mismatched those of their observed parents. Two could be explained by the occurrence of a null allele at one locus. The six remaining mismatches detected relied on mismatches at one locus, and they were not detected when we increased the potential genotyping error rate. We thus conclude that the Griffon Vulture is genetically monogamous, at least in low-density populations.

Sample environment and experimental set-up for inelastic x-ray scattering measurements of liquid hydrogen fluoride and HFx H2O1-x solutions.

In order to study the dynamic structure factor of hydrogen fluoride and its water solutions, we have realized a sample container able to resist these highly reacting hydrogen-bonded liquids and suitable for near-forward x-ray scattering experiments. The design and development of each part of the apparatus together with a discussion on the choice of the materials is reported. Two cells have been built for pure HF and for (HF)x(H2O)1–x solutions based on similar schemes but developed with different materials and some structural variations. Their contribution to the total scattered intensity has been measured. An example of inelastic x-ray scattering spectra at fixed temperature (T = 283 K) and momentum transfer (Q = 4 nm–1) is reported as a function of the concentration of hydrogen fluoride [(HF)x(H2O)1–x,with x = 0,0.2,0.4,0.73,1]