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The Large Hadron Collider (LHC) of CERN is a circular machine using superconducting magnets to achieve the large bending fields required to run two proton beams up to a 7 TeV energy. The maximum foreseen luminosity is set to L = 1034 cm2s-1. Halo particles that drifted away from the core of the beam must be removed for superconducting quenches to be avoided. This is achieved with a multi-stage cleaning system using two-sided collimators located at adequate positions in the machine. Due to the high luminosity value, the required inefficiency of the LHC collimation regions must be much lower than any other machine, around 0.00002 % in the top energy case. Detailed simulations ofrealistic operational conditions were performed to address the sensitivity ofthe cleaning system. Bearn 10ss maps show the distribution oflocal proton losses around the machine to the 10 cm level. The level of performance ofthe LHC collimation system is given in the ideal machine case and for a realistic scenario of orbit perturbation : the machine can only be run with respectively 43 % (ideal case) and 27 % (error model) of the nominal machine intensity. A list of characteristic loss locations is also given to help monitor beam losses at optimal locations regarding machine protection issues. A prototype collimator was tested in real LHC-like beam conditions. The control of the collimator gap was achieved down to the 50 μm 1evel, and interesting results on the actual beam physics with collimation were also obtained. The robustness of the graphite collimator jaws was also tested and results were compared with simulation programs to validate aIl previous estimates on energy deposition studies.

"Is Colombia going to be NATO's next global partner? In June 2013, the question was already worthy of attention, when Colombia and NATO entered into an 'Agreement on the Security of Information' that was signed between then-NATO Deputy Secretary General Ambassador Alexander Vershbow and Colombia's Defence Minister Juan Carlos Pinzón. While the deal encompassed not much more than sharing intelligence in areas of common concern, the agreement surely was 'a first step for future cooperation in the security field' and Ambassador Vershbow remarked that 'Colombia's expertise in enhancing integrity in the military is precisely the kind of substantive contribution that exemplifies the added value of cooperation." The question seems more immediate today, as Colombia has entered a new era, with the beginning of the demobilization of the Revolutionary Armed Forces of Colombia - People's Army (Fuerzas Armadas Revolucionarias de Colombia - Ejército del Pueblo - FARCEP), once the largest and oldest insurgency in Latin America, and the start of negotiations with other rebel groups ... A partnership with NATO would therefore serve as a way to acknowledge, encourage, and empower those who would like Colombia to move beyond its legacy of internal conflict to become a firm actor in international security"--Pages 1-2.

The Science of Synthesis Editorial Board, together with the volume editors and authors, is constantly reviewing the whole field of synthetic organic chemistry as presented in Science of Synthesis and evaluating significant developments in synthetic methodology. Four annual volumes updating content across all categories ensure that you always have access to state-of-the-art synthetic methodology.

A novel about rival spies who cooperate in order to stop an international group of murderers.

"The Delaunays' efforts to ensure that their work would be perceived as they had conceived it prompted several essays and lectures, numerous letters, and volumes of notebooks, most of which have never been translated into English. The light they shed on the life and thought of this exciting period in the history of art will be invaluable to any student of modern art"--