The FFAG R&D and medical application project RACCAM

JACoW web site http://accelconf.web.cern.ch/AccelConf/e06/Pre-Press/WEPCH161.pdf WEPCH161International audienceThe RACCAM project (Recherche en ACCelerateurs et Applications Medicales) has recently obtained fundings, extending over three years (2006-2008), from the French National Research Agency (ANR). RACCAM is a tripartite collaboration, involving (i) the CNRS Laboratory IN2P3/LPSC, (ii) the French magnet industrial SIGMAPHI, and (iii) the nuclear medecine Departement of Grenoble Hospital. The project concerns fixed field alternating gradient accelerator (FFAG) research on the one hand, and on the other hand their application as hadrontherapy and biology research machines. RACCAM's goal is three-fold, (i) participate to the on-going international collaborations in the field of FFAGs and recent concepts of "non-scaling" FFAGs, with frames for instance, the Neutrino Factory (NuFact) and the EMMA project of an electron model of a muon FFAG accelerator, (ii) design, build and experiment a prototype of an FFAG magnet proper to fulfil the requirements of rapid cycling acceleration, (iii) develop the concepts, and show the feasibility, of the application of such FFAG beams to hadrontherapy and to biology research

LTR Retrotransposons in Fungi

Transposable elements with long terminal direct repeats (LTR TEs) are one of the best studied groups of mobile elements. They are ubiquitous elements present in almost all eukaryotic genomes. Their number and state of conservation can be a highlight of genome dynamics. We searched all published fungal genomes for LTR-containing retrotransposons, including both complete, functional elements and remnant copies. We identified a total of over 66,000 elements, all of which belong to the Ty1/Copia or Ty3/Gypsy superfamilies. Most of the detected Gypsy elements represent Chromoviridae, i.e. they carry a chromodomain in the pol ORF. We analyzed our data from a genome-ecology perspective, looking at the abundance of various types of LTR TEs in individual genomes and at the highest-copy element from each genome. The TE content is very variable among the analyzed genomes. Some genomes are very scarce in LTR TEs (<50 elements), others demonstrate huge expansions (>8000 elements). The data shows that transposon expansions in fungi usually involve an increase both in the copy number of individual elements and in the number of element types. The majority of the highest-copy TEs from all genomes are Ty3/Gypsy transposons. Phylogenetic analysis of these elements suggests that TE expansions have appeared independently of each other, in distant genomes and at different taxonomical levels. We also analyzed the evolutionary relationships between protein domains encoded by the transposon pol ORF and we found that the protease is the fastest evolving domain whereas reverse transcriptase and RNase H evolve much slower and in correlation with each other

Competitive Repair by Naturally Dispersed Repetitive DNA during Non-Allelic Homologous Recombination

Genome rearrangements often result from non-allelic homologous recombination (NAHR) between repetitive DNA elements dispersed throughout the genome. Here we systematically analyze NAHR between Ty retrotransposons using a genome-wide approach that exploits unique features of Saccharomyces cerevisiae purebred and Saccharomyces cerevisiae/Saccharomyces bayanus hybrid diploids. We find that DNA double-strand breaks (DSBs) induce NAHR–dependent rearrangements using Ty elements located 12 to 48 kilobases distal to the break site. This break-distal recombination (BDR) occurs frequently, even when allelic recombination can repair the break using the homolog. Robust BDR–dependent NAHR demonstrates that sequences very distal to DSBs can effectively compete with proximal sequences for repair of the break. In addition, our analysis of NAHR partner choice between Ty repeats shows that intrachromosomal Ty partners are preferred despite the abundance of potential interchromosomal Ty partners that share higher sequence identity. This competitive advantage of intrachromosomal Tys results from the relative efficiencies of different NAHR repair pathways. Finally, NAHR generates deleterious rearrangements more frequently when DSBs occur outside rather than within a Ty repeat. These findings yield insights into mechanisms of repeat-mediated genome rearrangements associated with evolution and cancer

Development of an optimal analytical protocol for the extraction of persistent organic pollutants adsorbed on plastic debris in the environment

TH028 Development of an optimal analytical protocol for the extraction of persistent organic pollutants adsorbed on plastic debris in the environment K. Sakaguchi-Soeder, Technische Universitaet Darmstadt / Institute IWAR Chair of Material Flow Management and Resource Economy Germany; T. Neuveglise, Technische Universitaet Darmstadt / Department of Civil and Environmental Engineering; A. Goharnia, Technische Universitaet Darmstadt / Institue IWAR Chair of Material Flow Management and Resource Economy; M. Gottschling, Technische Universitaet Darmstadt / Institute IWAR Chair of Material Flow Management and Resource Economy Germany; A. van Oyen, Plastic Partner GmbH. Accumulation of persistent organic pollutants (POPs)-loaded microplastics (MPs) in the aquatic milieu is an emerging issue of international concern. Qualitative/quantitative determination of POPs on MPs is essential for the estimation of the impact of POPs-loaded MPs on a range of marine organisms. In general, hydrophobic pollutants like POPs are first extracted from the matrix, in this case plastic debris, using non-polar solvents. Then, the extract will be cleaned-up and analysed in e.g. gaschromatography/ mass-spectrometry (GC/MS). Some non-polar solvents applied for POP extraction, however, may dissolve plastic debris partially or completely, which disturb subsequence analyses. A number of methods have been reported for the extraction of POPs from MPs. Yet, the validity of these methods have not been fully discussed and the influence of polymers in extraction solvent on subsequent POP analysis has not been thoroughly investigated. The goal of the current study is the development of an optimal analytical protocol to extract POPs from different MPs. Known amounts of POPs were artificially charged on the surface of selected polymer particles, including preproduction resin pellets from different polymer type (polyethylene, PE; polystyrene, PS; polyethylene terephthalate PET, polypropylene, PP; poly vinyl chloride, PVC) in the laboratory. The POPs on plastic particles were extracted in selected solvents using soaking and sonication methods under different conditions. Solvents used in this study include n-hexane (nHex), isopropanol (iPrOH) and dichloromethane (DCM). Extraction methods and conditions were evaluated for a high extraction recovery, a high reproducibility, as well as for a minimal damage of polymer particles, i.e. carriers of POPs. The recovery rate and analytical reproducibility of POP was determined using gas chromatography-mass spectrometry (GC/MS). The loss of plastic weight was measured for the evaluation of the stability of plastic particles under given extraction conditions. Further, we investigated the influence of polymers dissolved in solvent on quantitative analysis for POPs. TU Darmstadt and CARAT are participants of an EU project “PLASTOX”, a consortium of a JPI Oceans’ Joint Action. TU Darmstadt is funded by BMBF

DESIGN OF IBA CYCLONE® 30XP CYCLOTRON MAGNET

IBA is currently developing an evolution of its famous Cyclone® 30 cyclotron. The Cyclone® 30XP cyclotron will be a multi-particle, multiport cyclotron capable of accelerating alpha particles up to 30 MeV (electrostatic extraction), deuteron (D-) beams between 7.5 and 15 MeV and proton (H-) beams between 15 and 30 MeV (stripping extraction). The magnet system has been updated with improved versions of IBA Cyclone 18/9 and Cyclone 70 features. At first, coil dimensions have been updated in order to raise the free space in the median plane to allow mounting a retractable electrostatic deflector system for the extraction of the alpha particle beam. Gradient corrector pole extensions, have been added to ease the alpha beam extraction. Finally, compensation for relativistic effects between H- (q/m=1/1) and D-/alpha (q/m=1/2) beams is made by the use of movable iron inserts located in two valleys, as is done in IBA Cyclone® 18/9 cyclotrons. These modifications could have an adverse effect on the flutter. In addition, the second harmonic induced by the movable iron inserts drives the machine in the 2.νr=2 resonance close to the extraction. As a consequence, modifications on the pole sectors and chamfers have been made in order to improve the flutter and eliminate harmful resonance up to extracted energies. After the presentation of the magnet features, some results on beam extraction are also discussed.IMP;Chinese Academy of Science

DESIGN OF IBA CYCLONE®11 CYCLOTRON MAGNET

The development of a new Cyclone®11 11MeV Hcyclotron is in progress at IBA. Such machine is designed for the production of radionuclides for nuclear medicine. This cyclotron is based on the existing Cyclone®10 that has been boosted to more than 11 MeV with as minor as possible change to the Cyclone®10 geometry. At first, the magnetic field has been raised by a small reduction of the valley depth. Additionally, the main coil current has been increased. Pole edge milling has been used to obtain the isochronous magnetic field shape. Beam optics in the magnet is excellent. Extraction is ensured by means of stripper foils mounted on carousels located at different azimuths allowing installation up to eight targets and dual beam extraction.IMP;Chinese Academy of Science

A procedure to evaluate different techniques for the extraction of pollutants from plastic debris in the environment

Once entered in the aquatic milieu, plastic wastes will be weathered and fragmented into smaller pieces. While migrating long distance for a long time, these plastic fragments accumulate a variety of pollutants including persistent organic pollutants (POPs) on their surface. For the estimation of ecological impacts of plastic debris in the environment on a range of marine organisms, therefore, it is important to understand the nature and extent of pollutants enriched on plastic debris. A number of methods are reported for the extraction of pollutants from plastic debris. However, it is difficult to compare different techniques or different conditions for the extraction of pollutants accumulated on plastic fragments, mainly, due to a lack of standardized methods for the determination of the efficiency of pollutant-extraction by different techniques. Here, we propose a procedure to evaluate different techniques for the extraction of pollutants from plastic debris in the environment. Firstly, we propose a quick and reproducible method for the production of plastic debris charged by a known amount of pollutants on the surface. The pollutantloaded plastic debris could be used as a reference material to determine the extraction efficiency. Using this quick method, we prepared resin pellets from five different polymer types charged by known amounts of pollutants. Pollutants selected for this study have a range of octanol/water partition coefficients (log Kow) between 3 and 6. Properties of the pellets were determined by CARAT GmbH (Bocholt, Germany). Secondly, we propose a procedure for the evaluation of extraction techniques. Extraction techniques and conditions are to be evaluated for a high extraction recovery, a high reproducibility, as well as for a minimal damage of plastic debris, i.e. carriers of pollutants. Here, we evaluated extraction efficiency by soaking and sonication in different solvents using the resin pellets charged with a known amount of pollutants. The extraction recovery was determined by comparing the extracted mass to the original mass of the pollutant on the pellets. Further, the loss of plastic weight was measured for the evaluation of the stability of plastic particles under given extraction conditions. TU Darmstadt and CARAT are participants of an EU project “PLASTOX”, a consortium of a JPI Oceans’ Joint Action. TU Darmstadt is funded by BMBF

UPGRADE OF IBA CYCLONE® 3 CYCLOTRON

Some specific applications of 15O2 need a stand alone production machine to avoid disrupting the hospital main PET cyclotron. Due to recent renewal in interest, IBA has decided to improve the design of its Cyclone® 3 which accelerates D+ ions to energy of more than 3 MeV and which was originally developed for this purpose. The main improvement relates to the magnetic structure. In the existing design the vertical focusing is obtained by four straight pole-sectors that are mounted on the circular base of the pole. In the new design these are replaced by three spiralled pole sectors. This modification changes the rotational symmetry from four to three and improves the vertical focusing properties of the machine. Also the main coil and the return yoke were slightly modified. This allowed increasing the extraction energy by about 10 % from 3.3 MeV to 3.6 MeV. This new design will improve the transmission in the cyclotron and will result in an extraction efficiency of more than 80% using an electrostatic deflector. For the prototype the goal is to obtain an extracted current of 50 μA. This value should rise to 70 μA for subsequent machines, representing a doubling of the existing performance. In the paper, results of magnetic field optimization and extraction calculations are presented.IMP;Chinese Academy of Science