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The article discusses a presentation by Bortolo Giuliano Maino at the 6th International Orthodontic Congress held in Paris, France, about two intraoral anchorage devices, the Spider Screw and the Midplant. Maino described the application of the devices and their flexibility in both adult and growing patients. He cited the advantage of the use of the Spider Crew in many clinical situations. He also highlighted the reliability of Midplant as an osseointegrated anchorage system.

Abstract: The assembly of the Corsica–Sardinia Batholith (C–SB) coincides with final shaping of the Variscan belt and represents a key structure to unravel the feedbacks between partial melting, rheology and the evolution of collisional orogens. This paper presents a model for the genesis of the Arzachena pluton (AZN), one of the major calc-alkaline massifs of the C–SB, based on U–Pb zircon dating, thermobarometry and structural analysis. Major and trace element compositions indicate that AZN has hybrid characteristics between that of typical S- and I-type granites, that could be explained in terms of incremental melting of a heterogeneous crustal source made of metatexites and Ordovician calc-alkaline granitoids. Growth of the pluton started around 320–315Ma with the emplacement at middle crustal level (0.37–0.4GPa) of granodioritic melts within narrow, conjugate, NW–SE sinistral and E–W dextral shear zones. The main growth stage (311+6/−4Ma) is marked by emplacement of large volumes of monzogranitic melts that induced a local decrease of the crustal strength expressed by horizontal channel flow driven by the gravity. Finally (307.6±3.5Ma), leucogranites emplaced within radial and peripheral dilatant fractures developed during the cooling of the main body. The transition from magmatic to sub-magmatic and HT-solid state fabric observed throughout AZN indicates that deformation plays a non-trivial role during the growth of the magmatic system. Restoring the position of the Corsica–Sardinia block to early Permian coordinates allow to recast the birth of the C–SB in a consistent geodynamic framework that conciliates the development of conjugates strike-slip structures, the oroclinal bending of the chain and the thermal relaxation. This study indicates that the C–SB had an active role during post-orogenic extension rather than being just a consequence of it. [Copyright &y& Elsevier]

Abstract: An upgrade proposal for the LHCb RICH detectors at the Large Hadron Collider at CERN is being developed at the INFN section of Milano Bicocca, based on multi-anode photomultiplier tubes. The application requires the fast readout of Cherenkov rings of photons, with single photon sensitivity, at an event rate up to 40MHz. The proposed readout chain is tailored for the R7600 multi-anode photomultiplier tubes from Hamamatsu, which proved to fit the single photon sensitivity requirement. The readout electronics for each pixel will be composed of an analog pulse shaper, a binary discriminator and additional digital circuitry to count the pulses. A prototype of the analog shaper was built with commercial discrete transistors in Silicon–Germanium (SiGe) Heterojunction technology. The tradeoff between response speed and power dissipation was investigated; and power as low as a few mW per channel could be achieved with response times of the order of one nanosecond. Furthermore, noise and jitter were evaluated, showing very good performances of the prototype. [Copyright &y& Elsevier]