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Career situation of first and presenting author Post-doctoral fellow. Introduction The use of methotrexate (MTX) for the treatment of rheumatoid arthritis (RA) is limited by serious adverse effects. Some effects, such as stomatitis and gastric ulcer, can be alleviated by folate supplement. Others are folate-independent, e.g. fibrosis of liver and lung. Moreover, MTX further elevates the micronuclei count, which is generally already increased in RA. In RA, inflamed tissue is characterized by up to 100-fold increased concentrations of reactive oxygen species (ROS, including hydrogen peroxide) compared to healthy tissue. A novel MTX prodrug, ROS101 in development for the treatment of RA, releases MTX at exposure to ROS. This restricts MTX exposure to target tissues with increased ROS levels, e.g. the synovial membrane in RA. Objectives To investigate the effect and toxicity of a targeted MTX prodrug in a rat CIA model of rheumatoid arthritis. Methods ROS101 was tested in a collagen induced arthritis (CIA) model in dark agouti (DA) rats (10 per group) against vehicle and 0.3 mg MTX i.p./day at equimolar doses. Arthritis was induced by s.c. injection of an emulsion of collagen type II in complete Freund’s adjuvant. Treatment was initiated at a mean arthritis severity score of 2/60. Blinded disease evaluation took place 3 times/week from day 10. Bone marrow cells for micronucleus test were obtained from the femur, pictures captured with LARS.4.8 software and analyzed blinded. Individual rat data were included until termination. Results Mean and maximum arthritis severity score was reduced in rats in the ROS101 group compared to vehicle (mean score 6.3±3.1 vs. 14.1±3.3, mean±SEM); (max score 12.6±5.3 vs. 32.3±5.3, mean±SEM, p Conclusions The CIA study in rats indicates that the MTX prodrug ROS101 may be efficacious for the treatment of RA at an equimolar dose compared to MTX, while avoiding adverse effects known to restrict treatment with MTX. Acknowledgements C.A. Hansen, co-founder of ROS Therapeutics. Disclosure of Interest V. Previtali: None declared, N. Woodworth: None declared, M. Hopkins: None declared, J. Petersen Shareholder of: ROS Therapeutics, Consultant for: ROS Therapeutics, I. Ahnfelt-Ronne Shareholder of: ROS Therapeutics, Consultant for: ROS Therapeutics, M. Clausen Shareholder of: ROS Therapeutics.

The effect of multiple volume reflections in one crystal was observed in each of several bent silicon strips for 400 GeV/c protons. This considerably increased the particle deflections. Some particles were also deflected due to channeling in one of the subsequent strips. As a result, the incident beam was strongly spread because of opposite directions of the deflections. A modified multi-strip deflector produced by periodic grooves on the surface of a thick silicon plate was used for these measurements. This technique provides perfect mutual alignment between crystal strips. Such multi-strip deflector may be effective for collider beam halo collimation and a study is planned at the CERN SPS circulating beam.

Spectral maxima of parametric X-ray radiation (PXR) produced by 400 GeV/c protons in bent silicon crystals aligned with the beam have been observed in an experiment at the H8 external beam of the CERN SPS. The total yield of PXR photons was about 10-6 per proton. Agreement between calculations and the experimental data shows that the PXR kinematic theory is valid for bent crystals with sufficiently small curvature as used in the experiment. The intensity of PXR emitted from halo protons in a bent crystal used as a primary collimator in a circular accelerator may be considered as a possible tool to control its crystal structure, which is slowly damaged because of irradiation. The intensity distribution of PXR peaks depends on the crystal thickness intersected by the beam, which changes for different orientations of a crystal collimator. This dependence may be used to control crystal collimator alignment by analyzing PXR spectra produced by halo protons., peer-reviewed

Experiments were performed at the CERN SPS with 120 GeV/c stored proton beams to assess the possibility of beam halo collimation assisted by bent crystals. A bent crystal was used to deflect horizontally by an angle of about 170 mu rad the beam halo protons in channeling states directing them into a 60 cm long tungsten absorber. The halo loss rate due to nuclear inelastic interactions of protons in the aligned crystal was up to five times smaller than for its amorphous orientation. Channeled fractions, (75 +/- 4)% and (85 +/- 5)% for the two tested silicon crystals, were measured by intercepting the deflected beam with another collimator located between the crystals and the absorber. The pixel detector (MEDIPIX) installed in a Roman pot inside the beam pipe was used to obtain visual images of the deflected beam. (C) 2010 Elsevier B.V. All rights reserved.

The knowledge of the critical current density in a wide temperature and applied magnetic field range is a crucial issue for the design of a superconducting magnet, especially for determining both current and temperature margins. The critical current density of LHC-type Nb-Ti strands of 0.82 and 0.48 mm diameter was measured by means of critical current and magnetization measurements at both 4.2 K and 1.9 K and for a broad magnetic field range (up to 11 T). For the magnetic field range common to both measurement methods, critical current density values as extracted from transport current and from magnetization data are compared and found fairly consistent. Our experimental data are compared to other sets from literature and to scaling laws as well

The Nb-Ti hard conductors used in LHC dipole and quadrupole magnets are Rutherford cables composed of several tens of strands. During the cabling process, the strands are severely compacted especially at the thin edge of the cable. In order to assess, on the whole wire length, the deformation effect on the transport current of the wires, LHC-type Nb-Ti superconducting strands of various types were flattened by means of rollers. The critical current was then measured as a function of deformation and applied magnetic field at both 4.3 K and 1.9 K. The measurements were performed for both orientations (flat face perpendicular or parallel to magnetic field). The critical current density anisotropy of such deformed strands and the correlation with magnetization effects are discussed. This study permits to better understand and to quantify the critical current degradation of few percent observed in strands due to cabling. Comparisons with wires extracted from Rutherford cables are presented

The Next European Dipole (NED) project is a EU funded program aiming at the realization of a 15 T accelerator-type of Nb3Sn dipole magnet. The objective of NED phase one is developing high performance Nb3Sn conductor in collaboration with European industry. The envisaged Rutherford type of cable consists of about 40 superconducting strands exhibiting a noncopper critical current density of 1500 A/mm2 at 4.2 K and 15 T. In the frame of conductor development, adequate critical current measurements in terms of accuracy and reproducibility should be ensured to qualify the ambitious strands produced. Therefore, a NED working group focuses at the establishment and implementation of appropriate and standardized procedures for sample preparation and mounting, critical current measurement, data analysis and reporting. A cross-calibration program between the institutes involved has been initiated by exchanging samples of Nb3Sn conductor from a single billet for critical current measurements, prepared at each institute. The experimental results of this program and the conclusive procedures for NED critical current measurements are presented and discussed

The transport properties of powder-in-tube processed superconducting tapes based on the Bi-2223 and MgB/sub 2/ compounds were measured at liquid helium temperature as a function of the magnetic field amplitude and orientation with respect to the conductors. Critical current measurements on short samples were performed in a magnetic field up to 20 T. From this data, we found that commercial multifilamentary Bi-2223 tapes, in spite of the well-established processing route, show some differences over a standard common trend, if manufactured by different suppliers. Nevertheless they all carried remarkable transport currents up to the highest magnetic field of measurement. The transport properties of MgB/sub 2/ tapes presented very different features depending on the thermo-mechanical treatment they were subjected to during the fabrication process. A small critical current was measured at a field as high as 16 T on a multifilamentary MgB/sub 2/ tape. In the magnetic field domain below 1 T, MgB/sub 2/ tapes carried critical currents in excess of 1000 A at a critical current density of greater than 4/spl middot/10/sup 5/ A/cm/sup 2/.

Nickel-sheathed MgB2 tapes were fabricated by means of the powder-in-tube method with a monocore configuration of the superconductor. The metallic tubes were filled with commercial reacted powders and cold-worked, respectively, by groove rolling, drawing, and rolling to flat tapes of about 4 mm in width and 0.35 mm in thickness. Portions of the manufactured conductors were heat-treated in an argon atmosphere at temperatures up to 940 °C. Conductors were characterized by transport measurements to determine the magnetic field dependence of the critical current density, the irreversibility line, as well as to establish an initial relationship between the thermo-mechanical treatment and the current carrying capacity of the manufactured MgB2 samples. Our optimized samples for the low field operation carry a critical current density of at least 4 × 105 A cm−2 at 4.2 K, 1 T. The main outcome of this study, however, is that the optimal heat treatment condition changes if the MgB2 conductor has to be employed respectively for a low- or high-field operation. Finally, the first successful demonstration of the current carrying capability of longer MgB2 tapes is also reported in this paper.

In the last years the LHC collimation system has been performing over the expectations, providing the machine with a nearly perfect efficient cleaning system[1]. Nonetheless, when trying to push the existing accelerators to and over their design limits, all the accelerator components are required to boost their performances. In particular, in view of the high luminosity frontier for the LHC, the increased intensity would ask for a more efficient cleaning system. In this framework innovative collimation solutions are under evaluation[2]: one option is the usage of an hollow electron lens for beam halo cleaning. This work intends to study the applicability of an the hollow electron lens for the LHC collimation, by evaluating the case of the existing Tevatron e-lens applied to the nominal LHC 7 TeV beam. New e-lens operation modes are here proposed to standard enhance the electron lens halo removal effect.

The time evolution of beam losses during a collimator scan provides information on halo diffusion and population. This is an essential input for machine performance characterization and for the design of collimation systems. Beam halo measurements in the CERN Large Hadron Collider were conducted through collimator scrapings in a dedicated beam study for the first time at 4 TeV. Four scans were performed with two collimators, in the vertical plane for beam 1 and horizontally for beam 2, before and after bringing the beams into collisions. Inward and outward steps were performed. A diffusion model was used to interpret the observed loss rate evolution in response to the collimator steps. With this technique, diffusion coefficients were estimated as a function of betatron oscillation amplitude from approximately 3 to 7 standard deviations of the transverse beam distribution. A comparison of halo diffusion and core emittance growth rates is also presented., peer-reviewed

The Next European Dipole (NED) Joint Research Activity was launched on 1st January 2004 to promote the development of high performance Nb$_{3}$Sn conductors in collaboration with European industry (aiming at a non-copper critical current density of 1500 A/mm2 at 4.2 K and 15 T) and to assess the suitability of Nb$_{3}$Sn technology to the next generation of accelerator magnets (aiming at an aperture of 88 mm and a conductor peak field of ~ 15 T). It is part of the Coordinated Accelerator Research in Europe (CARE) project, involves eight collaborators and is half-funded by the European Union. After briefly recalling the Activity organization, we report the main progress achieved over the last year, which includes: the manufacturing of a double-bath He II cryostat for heat transfer measurements through Nb$_{3}$Sn conductor insulation, detailed quench computations for various NED-like magnet configurations, the award of two industrial subcontracts for Nb$_{3}$Sn conductor development, the first results of a cross-calibration program of test facilities for Nb$_{3}$Sn wire characterization, detailed investigations of the mechanical properties of heavily cold-drawn Cu/Nb/Sn composite wires and the preliminary assessment of a new insulation system based on polyimide-sized fiber glass tapes. Last, we briefly review the efforts of an ongoing Working Group on magnet design and optimization.