Acylsulfonamide safety-catch linker : promise and limitations for solid-phase oligosaccharide synthesis

Safety-catch linkers are useful for solid-phase oligosaccharide synthesis as they are orthogonal to many common protective groups. A new acylsulfonamide safety-catch linker was designed, synthesized and employed during glycosylations using an automated carbohydrate synthesizer. The analysis of the cleavage products revealed shortcomings for oligosaccharide synthesis

GePEToS : A Geant4 Monte Carlo simulation package for Positron Emission Tomography

GePEToS is a simulation framework developed over the last few years for assessing the instrumental performance of future PET scanners. It is based on Geant4, written in Object-Oriented C++ and runs on Linux platforms. The validity of GePEToS has been tested on the well-known Siemens ECAT EXACT HR+ camera. The results of two application examples are presented : the design optimization of a liquid Xe micro-PET camera dedicated to small animal imaging as well as the evaluation of the effect of a strong axial magnetic field on the image resolution of a Concorde P4 micro-PET camera.Comment: 5 pages, 12 figures, submitted to IEEE Transactions on Nuclear Scienc

Premiers résultats des plongées Nautile de la campagne SUBPSO 1 sur la zone de collision "ride des Loyauté arc des Nouvelles-Hébrides" (Sud-Ouest Pacifique)

International audienceFour dives were conducted over the collision zone "Loyalty ridge/New Hebrides arc". On the Loyalty ridge, basaltic and rhyolitic breccias overlain by reef limestones were observed. An andesitic volcaniclastic sequence outcrops on the western flank of the New Hebrides arc. Near the trench, the Loyalty ridge has been sliced by normal faults along which the reef limestones collapsed of at least 4,000m. The unusual existence ofSW verging anticlines on the outer wall, 1,000m above the trench, was confirmed. These folds affect rocks ofthe lowerpartofthe ridge flank.Quatre plongées, réalisées sur la zone de collision «ride des Loyauté/arc des NouvellesHébrides », ont permis d'observer: (1) sur la ride des Loyauté, en mur externe de la fosse, des formations volcano-détritiques basaltiques et rhyolitiques, coiffées par des calcaires récifaux, le toutintensément fracturé; (2) sur le flanc occidental de l'arc néo-hébridais, en mur interne de la fosse, une série volcano-détritique andésitique. A l'approche de la fosse, des failles normales ont découpé la ride des Loyauté, amenant les calcaires récifaux jusqu'à des profondeurs de plus de 4000m. Enfin, la présence inhabituelle de plis déjetés vers le SW sur le mur externe, 1000 m au-dessus de la fosse, a été confirmée; ils semblent s'être développés aux dépens de matériel de la partie inférieure du flanc de la ride

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

Electrical tests of e. m. barrel presampler sectors

A description of the tests and electronics used to control the presampler sectors, before and after their assembly, is given. An example of the results obtained for the first two sectors, tested at room and liquid nitrogen temperatures, is shown

Electronic tests of the barrel presampler mother boards

The electrical characteristics of the barrel presampler mother boards are recalled. The results of the tests of the first full-size mother board are presented. They satisfy our specifications

Premiers résultats des plongées de la campagne SUBPSO 1 dans la zone de collision des rides d'Entrecasteaux et de l'arc des Nouvelles-Hébrides

International audienceGeological cross-sections,constructed from observations and samples collected during seven dives of theFrench submersible Nautile,reveal that the inner wall of the New Hebrides trench, in front of the North d'Entrecasteaux ridge and the Bougainville guyot,is primarily composed of volcanic and volcaniclastic rocks, most likely shed from the arc. Observations indicate that the bedding of thearc-slope rocks,which generally slopes trench ward in this collision zone,dips steeply (40-80°) arcward near the contact of the colliding features. In this particular area, arc-slope rocks are generally highly fractured and sheared, an exception being rocks forming the ridge east of the Bougainville guyot.Arc-slope rocks are deeply incised by erosional channels and show numerous fresh slump scars. These scars confirm the importance of mass wasting along the deformation front. No evidence for fluid venting,such as clams and mud volcanoes,was observed during the dives.Les coupes géologiques réalisées à partir de sept plongées du Nautile ont montré que le mur interne de la fosse des Nouvelles-hébrides,en face de la ride Nord d'Entrecasteaux et du guyot Bougainville,est essentiellement constitué par des formations volcaniques et volcano-détritiques provenant probablement de l'arc. Ces formations, généralement inclinées vers la fosse, ont,au contact de la ride et du guyot,rebroussées vers le haut et pentées de 40 à 80°vers l'arc. A ces niveaux,les roches sont intensément fracturées et cisaillées à l'exception de celles constituant le bourrelet qui surplombe le toit du guyot Bougainville.Le mur interne présente enfin une morphologie remarquable comprenant des loupes d'arrachement gravitaire,des chenaux d'érosion, des canyons et,localement,des marmites de géant.Ces figures confirment l'importance de l'érosion gravitaire le long du front de déformation.Aucune manifestation de sorties de fluides n'a été observée lors de ces plongées

Geology of the d'Entrecasteaux - New Hebrides arc collision zone : results from a deep submersible survey

International audienceDuring the SuBPSOl cruise, seven submersible dives were conducted between water depths of 5350 and 900 m over the collision zone between the New Hebrides island arc and the d'Entrecasteaux Zone (DEZ). The DEZ, a topographic high on the Australian plate, encompasses the North d'Entrecasteaux Ridge (NDR) and the Bougainville guyot, both of which collide with the island-arc slope. In this report we use diving observations and samples, as well as dredging results, to analyse the geology of the Bougainville guyot and the outer arc slope in the DEZ-arc collision zone, and to decipher the mechanisms of seamount subduction. These data indicate that the Bougainville guyot is a middle Eocene island arc volcanocapped with reef limestones that appear to have been deposited during the Late Oligocene to Early Miocene and in Miocene-Pliocene times. This guyot possibly emerged during the Middle and Late Miocene, and started to sink in the New Hebrides trench after the Pliocene. The rocks of the New Hebrides arc slope, in the collision zone, consist primarily of Pliocene-Recent volcaniclastic rocks derived from the arc, and underlying fractured island-arc volcanic basement, possibly of Late Miocene age. However, highly sheared, Upper Oligocene to Lower Miocene nannofossil ooze and chalk are exposed at the toe of the arc slope against the northern flank of the NDR. Based on a comparison with cores collected at DSDP Site 286, the ooze and chalk can be interpreted as sediments accreted from the downgoing plate. East of the Bougainville guyot an antifonn that developed in the arc slope as a consequence of the collision reveals a 500-m-thick wedge of strongly tectonized rocks, possibly accreted from the guyot or an already subducted seamount. The wedge that is overlain by less deformed volcaniclastic island-arc rocks and sediments includes imbricated layers of Late Oligocene to Early Miocene reef and micritic limestones. This wedge, which develops against the leading flank of the guyot, tends to smooth its high-drag shape. A comparison between the 500-m-thick wedge of limestones that outcrops southeast of the guyot and the absence of such a wedge over the flat top of the guyot, although the top is overthrust by island-arc rocks and sediments, can be interpreted to suggest that the wedge moves in the subduction zone with the guyot and facilitates its subduction by streamlining