performance and aging of opera bakelite rpcs

OPERA is an experiment dedicated to the observation of νμ into ντ oscillations through τ appearance on the CNGS beam. The experiment is composed by two identical super-modules, each with a target section (made of emulsion/lead bricks alternated to a scintillator Target Tracker) and a muon spectromter (instrumented with bakelite electrodes RPCs and drift tubes). The OPERA RPC system is composed of about 1000 RPCs for an instrumented area of 3000 m2. The RPCs are operated in streamer mode and flushed with the gas mixture Ar/C2H2F4/i−C4H10/SF6 = 75.4/20.0/4.0/0.6 at five refills/day in open flow. The present performance of the RPC system after six years of operation are presented. The aging status of the detector is also described

EGFR and K-Ras mutations in women with lung adenocarcinoma: implications for treatment strategy definition.

BackgroundWe aimed at investigating the outcomes of female patients with stage IIIB-IV adenocarcinoma of the lung according to EGFR and K-Ras mutational status.MethodsOne hundred and three consecutive female patients genotyped at a single Italian Institution were analyzed. Patients were planned to receive first-line platinum-based chemotherapy (CT) and a salvage treatment with anti-EGFR tyrosine-kinase inhibitors (TKIs) was proposed irrespective of tumor mutational status. EGFR (exons 18¿21) and K-Ras (exon 2, codons 12¿13) mutations were evaluated by real-time PCR and pyrosequencing. The association of mutational status with clinical variables and treatment benefit was investigated by chi-square test and log-rank test.ResultsEGFR and K-Ras mutations were found in 31 (30%) and 13 (15%) cases, respectively. Sixty-six patients received platinum CT: no correlation was observed between EGFR or K-Ras mutational status and response rate (RR) (p¿>¿0.05). However, patients treated with first-line CT harboring EGFR activating mutations experienced a significantly reduced progression-free survival (PFS) in comparison with wild-type ones (4.4 vs. 6.4 months, respectively; HR 0.597, 95%CI 0.287-0.975; p¿=¿0.048). Thirty-nine patients received salvage treatment with erlotinib: EGFR activating mutations were significantly correlated with RR (60% vs. 12.5%; p¿=¿0.004) and PFS (11.4 vs. 4.5 months; HR 0.491, 95%CI 0.216-0.936; p¿=¿0.044). Responses to erlotinib were not reported among women with K-Ras mutant tumors, while 50% of those with wild-type K-Ras achieved an objective remission (p¿=¿0.296). Median PFS (3.5 vs. 8.8 months; HR 0.284, 95%CI 0.015-0.510; p¿=¿0.010) and OS (3.9 vs. 19.8 months; HR 0.158, 95%CI 0.001-0.075; p¿<¿0.001) were significantly shorter among K-Ras mutant patients treated with TKI.ConclusionsIn our population of Caucasian women with advanced lung adenocarcinoma we observed that the presence of EGFR activating mutations correlates with a significant reduction in the benefit from first-line platinum-based CT, emphasizing the importance of an upfront use of anti-EGFR TKIs in this patient subset. K-Ras mutations seem to correlate with a detrimental effect from anti-EGFR TKI, but this finding deserves further investigation

Time correlation measurements from extensive air showers detected by the EEE telescopes

Time correlated events due to cosmic muons from extensive air showers have been detected by means of telescope pairs of the EEE (Extreme Energy Events) Project array. The coincidence rate, properly normalized for detector acceptance, efficiency and altitude location, has been extracted as a function of the relative distance between the telescopes. The results have been also compared with additional measurements carried out by small scintillator detectors at various distances

Recent results and performance of the multi-gap resistive plate chambers network for the EEE Project

The Extreme Energy Events (EEE) Project is devoted to the study of Extensive Atmospheric Showers through a network of muon telescopes, installed in High Schools, with the further aim of introducing young students to particle and astroparticle physics. Each telescope is a tracking detector composed of three Multi-gap Resistive Plate Chambers (MRPC) with an active area of 1.60 × 0.80 m(2). Their characteristics are similar to the ones built for the Time Of Flight array of the ALICE Experimentat LHC . The EEE Project started with a few pilot towns, where the telescopes have been taking data since 2008, and it has been constantly extended, reaching at present more than 50 MRPCs telescopes. They are spread across Italy with two additional stations at CERN, covering an area of around 3 × 10(5) km(2), with a total surface area for all the MRPCs of 190 m(2). A comprehensive description of the MRPCs network is reported here: efficiency, time and spatial resolution measured using cosmic rays hitting the telescopes. The most recent results on the detector and physics performance from a series of coordinated data acquisition periods are also presented

The DarkSide direct dark matter search with liquid argon

International audienceThe DarkSide-50 direct dark matter detector is a liquid argon time projection chamber (TPC) surrounded by a liquid scintillator neutron veto (LSV) and a water Cerenkov muon veto (WCV). Located under 3800 m.w.e. at the Laboratori Nazionali del Gran Sasso, Italy, it is the only direct dark matter experiment currently operating background free. The atmospheric argon target was replaced with argon from underground sources in April, 2015. The level of 39Ar, a β emitter present in atmospheric argon (AAr), has been shown to have been reduced by a factor of (1.4 ± 0.2) x 103. The combined spin-independent WIMP exclusion limit of 2.0 x 10−44 cm2 (mχ = 100 GeV/c2) is currently the best limit on a liquid argon target