ECR Ion sources for radioactive ion beam production

17th workshop on ECR Ion Sources and their Applications, Lanzhou, Chine (2006)International audienceECRIS's dedicated to radioactive ion producton must be as efficient as those used for production of stable elements, but in addition they are subject to more specific constraints such as radiation hardness, short atom-to-ion transformation time, beam purity and low cost. Up to now, different target/ion-source system (TISSs) have been designed, using singly-charged ECRISs, multi-charged ion sources or an association of singly-to-multi-charged ECRISs. The main goal, constraints and advantages of different existing ECR setups wil be compared before a more detailed description is given of the one designed for the SPIRAL II project and ist future improvements

METALLIC ION DEVELOPMENTS AT GANIL

Radioactive ion beams (RIB) are routinely produced at GANIL by fragmentation of the projectile. A possible way to improve the RIB intensity is to increase the primary beam intensity impinging the target. Although high intensities can be obtained with an ECR ion source for gaseous elements, it is more difficult for metallic elements due to the poor ionization efficiency of the source. This report deals with metallic ion beam production at high intensity. Experimental results for Ca, Ni and Fe are presented. The oven and the MIVOC methods are compared

Combination of immortalization and inducible death strategies to generate a human mesenchymal stromal cell line with controlled survival

The hTERT-immortalization of human bone marrow-derived Mesenchymal Stromal Cells (hMSCs) was proposed to address availability/standardization issues for experimental or clinical studies, but raised concerns due to possible uncontrolled growth or malignant cell transformation. Here we report a method to generate a hMSCs line with controlled survival, through the implementation of a pre-established suicide system (inducible caspase 9, iCasp9) in hTERT-transduced hMSCs. Primary hMSCs were successfully immortalized (< 280PD) and further transduced with the iCasp9 device. A clone was selected and shown to maintain typical properties of primary hMSCs, including phenotype, differentiation and immunomodulation capacities. The successive transductions did not induce tumorigenic transformation, as assessed by analysis of cell cycle regulators and in vivo luciferase-based cell tracking. Cells could be efficiently induced toward apoptosis (< 95%) both in vitro and in vivo. By combining the opposite concepts of `induced-life’ and `inducible-death’, we generated a hMSCs line with defined properties and allowing for temporally controlled survival. The cell line represents a relevant tool for medical discovery in regenerative medicine and a potential means to address availability, standardization and safety requirements in cell & gene therapy. The concept of a hTERT-iCasp9 combination, here explored in the context of hMSCs, could be extended to other types of progenitor/stem cells

Production d'un nouveau faisceau d'ions au GANIL : le Titane

Depuis une trentaine d'années, le GANIL produit et accélère des faisceaux ions stables pour la communauté scientifique. Les ions accélérés sont de type gazeux ou métallique avec des énergies variant de 3,8 à 95Mev/A. Les progrès en termes de production de nouveaux éléments, d'intensité, de stabilité et d e reproductibilité résultent d'une activité continue de développement de nouveaux faisceaux. La production et la fourniture d'un faisceau de Titane 50 est depuis plusieurs années une demande récurrente des physiciens. Pour produire ce faisceau avec une source d'ions de type ECR4, nous nous sommes orientés vers la méthode MIVOC ( M etallic I ons fom V olatile C ompounds) en utilisant un composé organo - métallique, le Titanocène. L'utilisation de cette molécule est désormais envisageable suite au développement d e sa technique de synthèse par l'IPHC de Strasbourg. Après accélération par CSS1, et en prenant les rendements standards des accélérateurs du GANIL, un faisceau de 50 Ti 11+ à 4.8 MeV/A pourra être fourni sur cible avec une intensité de l'ordre 6 μAe (avec un échantillon synthétisé à partir d'un isotope enrichi à 90%)

Short-term feeding behaviour has a similar structure in broilers, turkeys and ducks

1. This study is the first to quantitatively compare the structure of feeding behaviour of broilers, ducks and turkeys as recorded by electronic feeders. It tests the hypothesis that this structure is so similar that the same models would be suitable to group the feeding behaviour of these species into meals. Visits to electronic feeders were recorded from 3470 broilers, 3314 turkeys and 480 ducks. The frequency distributions of the length of short intervals between visits to feeders varied between species as a result of differences in the number of visits within a feeding bout, the frequency of re-visits to the same feeder and probably in the likelihood of birds drinking within meals. The lengths of longer day-time intervals between visits to feeders were all log-normally distributed. Disaggregation of these intervals by feeding strategy (meal frequency) showed that the probability of birds starting to feed increased with time since feeding last in all species, which is consistent with the satiety concept. Two methods, one based on fitting a truncated log-normal, function, the other on observed changes in the probability of birds starting to feed with time since last feeding, gave very similar meal criteria estimates. These ranged from 1050 to 1200 s in broilers, 1650 to 1725s in ducks and 1250 to 1320 s in turkeys. There were large between-species differences in the average number of daily meals, intake per meal, and feeding rate. Despite this variation, the overall structure of feeding behaviour of broilers, ducks and turkeys was so similar that the same models were suitable for application in all three species. This would allow for standardised analyses of feeding behaviour of different avian species kept in different husbandry systems. © 2010 British Poultry Science Ltd

Effect of the plasma chamber radius on the high charge state production in an ECR ion source

International audienceTwo versions of the 18 GHz PHOENIX ECR ion source have been developed in the framework of the SPIRAL2 project. The former design (V2) has a compact plasma chamber volume of 0.6 liter with a diameter of 62 mm. A new design (V3) has been developed at LPSC with a larger diameter of 89 mm (chamber volume 1.4 liter) with enhanced pumping features. Since the two versions have nearly the same axial mirror structure and the same radial magnetic field intensity at the wall, it is of interest to compare their performances as a function of the plasma chamber radius. Experiments have shown an improvement of high charge state production of Argon between V2 (45 µA Ar14+, 6 µA Ar16+) and V3 (120 µA Ar14+, 58 µA Ar16+). Results are discussed and explained as a consequence of the increase of the ECR zone volume