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The Dark Energy Survey Collaboration has completed construction of the Dark Energy Camera (DECam), a 3 square degree, 570 Megapixel CCD camera which will be mounted on the Blanco 4-meter telescope at CTIO. DECam will be used to perform the 5000 sq. deg. Dark Energy Survey with 30% of the telescope time over a 5 year period. During the remainder of the time, and after the survey, DECam will be available as a community instrument. All components of DECam have been shipped to Chile and post-shipping checkout finished in Jan. 2012. Installation is in progress. A summary of lessons learned and an update of the performance of DECam and the status of the DECam installation and commissioning will be presented.

Heat and charge transport perpendicular to the plane in five Co/Cu stacks are studied using AC temperature gradients in the presence of a DC current. Large peaks in AC voltage response versus applied field are observed. This effect, measured only in reversible magnetization reversal modes and at sharp values of magnetic fields, suggests that an extra dissipation process is produced at well-defined magnetic configurations.

Reference EPFL-ARTICLE-147569doi:10.1103/PhysRevB.73.052410View record in Web of Science Record created on 2010-03-23, modified on 2017-05-12

Spin-dependent transport in granular metallic nanostructures has been investigated by means of a thermoelectric measurement. Cobalt clusters of well-defined size ( = 15 and 600), embedded in copper and silver matrices, show magnetic field responses of up to several hundred percent at low temperature. The experimental observations are identified as due to spin mixing. The influence of cluster size and matrix are discussed.

The mixed effects of heat and charge transports have been studied at room temperature for NiCu and CoCu multilayers with currents perpendicular to the interfaces as well as Ni and Co homogeneous nanowires. In order to carry out this analysis, magnetothermogalvanic voltage (MTGV) measurements have been performed. The method consists in monitoring an alternating voltage response that arises when an oscillation of the temperature of the nanostructure is applied and a steady current crosses the nanostructure. Different responses were observed for thicknesses of the ferromagnetic layer larger or shorter than the spin diffusion length. Qualitatively different MTGV profiles were also observed for Ni and Co homogeneous nanowires. These results demonstrate the importance of spin relaxation processes produced in ferromagnetic/nonferromagnetic (FM/NF) interfaces as well as in FM layers for the MTGV response. © 2006 American Institute of Physics.

The spin transfer torque model applied in the context of a Fokker-Planck analysis (Li and Zhang 2004 Phys. Rev. B 69 134416) is shown to account for a complete set of statistical data for switching times obtained with pseudo spin-valves (Fabian et al 2003 Phys. Rev. Lett. 91 257209). Current densities of the order of 10(7) A cm(-2) injected in Co/Cu/Co bilayers electrodeposited in nanoporous membranes gave rise to magnetization switching. Statistics could be accumulated on one single nanowire at a time: the field at which the average residence times in parallel and antiparallel configurations were equal, these times as a function of current, and the ratio of the times as a function of current and field.

Heat transport perpendicular to the plane of magnetic multilayers is monitored with ac temperature gradients in the presence of a direct charge current. A very strong dependence on the applied magnetic field of the voltage response to the ac gradient is observed using Co∕Cu multilayered nanowires. The effect is interpreted as a Peltier effect for a one-dimensional heat flux.

Glioblastoma multiforme (GBM) is the most common primary brain tumour in adults and one of the most aggressive cancers. PARP-1 is a nuclear protein involved in multiple facets of DNA repair and transcriptional regulation. In this study we dissected the action of PARP inhibition in different GBM cell lines with either functional or mutated PTEN that confers resistance to diverse therapies. In PTEN mutant cells, PARP inhibition induced a severe genomic instability, exacerbated homologous recombination repair (HR) deficiency and down-regulated the Spindle Assembly Checkpoint (SAC) factor BUBR1, leading to mitotic catastrophe (MC). EGFR gene amplification also represents a signature of genetic abnormality in GBM. To more effectively target GBM cells, co-treatment with a PARP inhibitor and an EGFR blocker, erlotinib, resulted in a strong suppression of ERK1/2 activation and in vivo the combined effect elicited a robust reduction in tumour development. In conclusion, PARP inhibition targets PTEN-deficient GBM cells through accentuation of SAC repression and aggravation of HR deficiency, leading to the induction of genomic instability and eventually deriving to mitotic catastrophe (MC); the inhibition of PARP and co-treatment with an inhibitor of pro-survival pathways strongly retarded in vivo gliomagenesis.

Galaxy surveys require support from massive datasets in order to achieve precise estimations of cosmological parameters. The CosmoHub platform (https://cosmohub.pic.es), a web portal to perform interactive analysis of massive cosmological data, and the SciPIC pipeline have been developed at the Port d'Informaci\'o Cientifica (PIC) to provide this support, achieving nearly interactive performance in the processing of multi-terabyte datasets. Cosmology projects currently supported include European Space Agency Euclid space mission, the Dark Energy Survey (DES), the Physics of the Accelerating Universe (PAU) survey and the Marenostrum Institut de Ciencies de l'Espai Simulations (MICE). Support for additional projects can be added as needed. CosmoHub enables users to interactively explore and distribute data without any SQL knowledge. It is built on top of Apache Hive, part of the Apache Hadoop ecosystem, which facilitates reading, writing, and managing large datasets. More than 50 billion objects, from public and private data, as well as observed and simulated data, are available. Over 500 registered scientists have produced about 2000 custom catalogs occupying 10TiB in compressed format over the last three years. All those datasets can be interactively explored using an integrated visualization tool. The current implementation allows an interactive analysis of 1.1 billion object datasets to complete in 45 seconds. The SciPIC scientific pipeline has been developed to efficiently generate mock galaxy catalogs using as input a dark matter halo population. It runs on top of the Hadoop platform using Apache Spark, which is an open-source cluster-computing framework. The pipeline is currently being calibrated to populate the full sky Flagship dark matter halo catalog produced by the University of Zurich, which contains about 44 billion dark matter haloes in a box size of 3.78 Gpc/h. The resulting mock galaxy catalog is directly stored in the CosmoHub platform.

• Three hundred seventeen patients with toxic oil syndrome caused by ingestion of denatured rapeseed oil were followed up after one year. Total mortality for the 317 patients was 4.4%. After 12 months, 3.2% of the surviving patients have a severe motor neuropathy, 52.9% are asymptomatic, and the remaining 39.4% have mild residual myalgia. The cause of death in seven patients during the acute phase of toxic oil syndrome was respiratory failure due to interstitial pneumonitis with cerebral edema. The death of five patients in the second phase was due to motor neuropathy that involved respiratory muscles and was complicated by aspiration pneumonia. ( Arch Intern Med 1984;144:254-256)