197 research outputs found
Performance of the readout system for MONOLITH
Abstract In this paper, we describe the performance of the readout system for MONOLITH developed at the LNGS. This system is based on the use of flat cables as readout elements, instead of the conventional copper strips. The advantages of flat cable strips are the good performance, the easy installation and the possibility to realize complex readout systems. The X -coordinate readout system (X-system) is composed by 15 m long, Flat Cable Strips (FCS). The distribution of the time difference between the streamer signals transmitted at both the ends of the X-system FCS has a sigma resolution of the order of 100 ps . This resolution allows the measurement of the particle direction by means of the time-of-flight technique and can be exploited to measure the Y -coordinate with a resolution in the order of 1 cm . The Y -coordinate system is composed by short FCS connected together by a flat cable acting as a bus line. It allows the installation of the electronics outside the apparatus minimizing the number of channels
Performance of glass RPC with industrial silk-screen-printed electrodes
In this paper we describe the performance of several Glass RPCs, where the water-based graphite coating is replaced by a synthetic coating applied using the screen printing technique. As expected, the performance of the detectors is good and reproducible due to the accurate control of the coating resistivity value. The resistance of the coating to the action of mechanical and chemical agents permits an easy electrode cleaning and mounting with respect to the RPC coated with the graphite varnish. This coating, together with the use of float glass as electrode material, allows an industrial production, where the detector characteristics can be tailored as a function of the experiment requirements
Cancer Stem Cells Sensitivity Assay (STELLA) in Patients with Advanced Lung and Colorectal Cancer: A Feasibility Study.
Cancer stem cells represent a population of immature tumor cells found in most solid tumors. Their peculiar features make them ideal models for studying drug resistance and sensitivity. In this study, we investigated whether cancer stem cells isolation and in vitro sensitivity assay are feasible in a clinical setting.
METHODS:
Cancer stem cells were isolated from effusions or fresh cancer tissue of 23 patients who progressed after standard therapy failure. Specific culture conditions selected for immature tumor cells that express markers of stemness. These cells were exposed in vitro to chemotherapeutic and targeted agents.
RESULTS:
Cancer stem cells were extracted from liver metastases in 6 cases (25%), lung nodules in 2 (8%), lymph node metastases in 3 (12.5%) and pleural/peritoneal/pericardial effusion in 13 (54%). Cancer stem cells were successfully isolated in 15 patients (63%), including 14 with lung cancer (93.3%). A sensitivity assay was successfully performed in 7 patients (30.4%), with a median of 15 drugs/combinations tested (range 5-28) and a median time required for results of 51 days (range 37-95).
CONCLUSION:
The approach used for the STELLA trial allowed isolation of cancer stem cells in a consistent proportion of patients. The low percentage of cases completing the full procedure and the long median time for obtaining results highlights the need for a more efficient procedure.
TRIAL REGISTRATION:
ClinalTrials.gov NCT01483001
Ageing and recovering of glass RPC
The glass Resistive Plate Chambers efficiency before and after water vapour flushing have been studied. The efficiency has been observed to rapidly drop to the level of 30% after a few days. After few hours of ammonia flushing, a full recover of the device occurred. Surprisingly, further flushing with water vapour had no effect on the efficiency, suggesting a treatment before the use in an experiment and/or whenever the performance is poor. In this work experimental results on tests at high temperature (up to 55âC), high rate (up to 100Hz/cm2) and ageing (up to 10mC/cm2) are reported
Glass resistive plate chambers in the OPERA experiment
Abstract OPERA is an underground neutrino oscillation experiment to search for Îœ Ï appearance from a pure Îœ ÎŒ beam produced at CERN. To flag the events due to the neutrino interactions with the rock surrounding the OPERA detector, a large VETO system, based on the use of Glass Resistive Plate Chambers (GRPC) has been realized. We describe the detectors, the tests performed before the installation in the underground laboratories and the monitor system for the water pollution in the GRPC gas mixture
The Extreme Energy Events HECR array: status and perspectives
The Extreme Energy Events Project is a synchronous sparse array of 52
tracking detectors for studying High Energy Cosmic Rays (HECR) and Cosmic
Rays-related phenomena. The observatory is also meant to address Long Distance
Correlation (LDC) phenomena: the network is deployed over a broad area covering
10 degrees in latitude and 11 in longitude. An overview of a set of preliminary
results is given, extending from the study of local muon flux dependance on
solar activity to the investigation of the upward-going component of muon flux
traversing the EEE stations; from the search for anisotropies at the sub-TeV
scale to the hints for observations of km-scale Extensive Air Shower (EAS).Comment: XXV ECRS 2016 Proceedings - eConf C16-09-04.
KRAS has a role in acquired resistance to EGFR-TKIs in NSCLC: an analysis on circulating tumor DNA
Abstract not availabl
Results from the first use of low radioactivity argon in a dark matter search
Liquid argon is a bright scintillator with potent particle identification
properties, making it an attractive target for direct-detection dark matter
searches. The DarkSide-50 dark matter search here reports the first WIMP search
results obtained using a target of low-radioactivity argon. DarkSide-50 is a
dark matter detector, using two-phase liquid argon time projection chamber,
located at the Laboratori Nazionali del Gran Sasso. The underground argon is
shown to contain Ar-39 at a level reduced by a factor (1.4 +- 0.2) x 10^3
relative to atmospheric argon. We report a background-free null result from
(2616 +- 43) kg d of data, accumulated over 70.9 live-days. When combined with
our previous search using an atmospheric argon, the 90 % C.L. upper limit on
the WIMP-nucleon spin-independent cross section based on zero events found in
the WIMP search regions, is 2.0 x 10^-44 cm^2 (8.6 x 10^-44 cm^2, 8.0 x 10^-43
cm^2) for a WIMP mass of 100 GeV/c^2 (1 TeV/c^2 , 10 TeV/c^2).Comment: Accepted by Phys. Rev.
Introducing the âanalogs for Venusâ geologically recent surfacesâ initiative: an opportunity for identifying and analyzing recently active volcano-tectonic areas of Venus trough a comparative study with terrestrial analogs
Several missions to Venus have been recently selected for launch [1â6], opening a new era for the exploration of the planet. One of the key questions that the future missions need to address is whether Venus is presently volcanically active [7â15]. Studying areas of active volcanism and tectonism on Venus is crucial to reveal clues about the geologic past of the planet, as well as provide information about the volatile content of its interior and the formation of its dense atmosphere. The âAnalogsfor VENusâ GEologically Recent Surfacesâ (AVENGERS) initiative aims to build a comprehensive database of terrestrial analog sites for the comparative study of recent and possibly on- going volcanic activity on Venus. Besides its scientific relevance, the AVENG- ERS initiative also acts as a bridge for international scientific collaboration, including the leadership and/or team members from the currently selected missions to Venus
Characterization of SABRE crystal NaI-33 with direct underground counting
Ultra-pure NaI(Tl) crystals are the key element for a model-independent
verification of the long standing DAMA result and a powerful means to search
for the annual modulation signature of dark matter interactions. The SABRE
collaboration has been developing cutting-edge techniques for the reduction of
intrinsic backgrounds over several years. In this paper we report the first
characterization of a 3.4 kg crystal, named NaI-33, performed in an underground
passive shielding setup at LNGS. NaI-33 has a record low K contamination
of 4.30.2 ppb as determined by mass spectrometry. We measured a light
yield of 11.10.2 photoelectrons/keV and an energy resolution of 13.2%
(FWHM/E) at 59.5 keV. We evaluated the activities of Ra and Th
inside the crystal to be Bq/kg and Bq/kg,
respectively, which would indicate a contamination from U and
Th at part-per-trillion level. We measured an activity of 0.510.02
mBq/kg due to Pb out of equilibrium and a quenching factor of
0.630.01 at 5304 keV. We illustrate the analyses techniques developed to
reject electronic noise in the lower part of the energy spectrum. A cut-based
strategy and a multivariate approach indicated a rate, attributed to the
intrinsic radioactivity of the crystal, of 1 count/day/kg/keV in the
[5-20] keV region
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