In the last few years, an intense R &D activity on particle detectors for future HEP applications has been carried on with the aim of developing new techniques as well as studying the performance of ...already existing detectors when operated in a high rate environment. As for Resistive Plate Chamber detectors, the main challenges to face are the improvement of their detection capabilities and longevity at very high-rates, and the search for new eco-friendly gasmixtures free from greenhouse components. Results obtained in the framework of the RPC ECOGas@GIF++ Collaboration on a thin-Resistive Plate Chamber exposed at the CERN Gamma Irradiation Facility and operated with eco-friendly gas mixtures based on Tetrafluoropropene and Carbon dioxide will be discussed in this paper.
Results obtained by the RPC ECOgas@GIF++ Collaboration, using Resistive Plate Chambers operated with new, eco-friendly gas mixtures, based on tetrafluoropropene and carbon dioxide, are shown and ...discussed in this paper. Tests aimed to assess the performance of this kind of detectors in high-irradiation conditions, analogous to the ones foreseen for the coming years at the Large Hadron Collider experiments, were performed, and demonstrate a performance basically similar to the one obtained with the gas mixtures currently in use, based on tetrafluoroethane, which is being progressively phased out for its possible contribution to the greenhouse effect. Long term aging tests are also being carried out, with the goal to demonstrate the possibility of using these eco-friendly gas mixtures during the whole High Luminosity phase of the Large Hadron Collider.
SHiP (Search for Hidden Particles) is a newly designed fixed target facility, proposed at the CERN SPS accelerator, with the aim of complementing searches for New Physics at LHC by searching for ...light long-lived exotic particles with masses below a few GeV/c2. The sensitivity to Heavy Neutrinos will allow for the first time probing a region of the parameter space where Baryogenesis and active neutrino masses and oscillation could also be explained. A dedicated detector, based on OPERA-like bricks, will provide the first observation of the tau anti-neutrino. Moreover, ντ and ν̄τ cross-sections will be measured with a statistics 1000 times larger than currently available data and will allow extracting the F4 and F5 structure functions, never measured so far. Charm physics studies will be performed with significantly improved accuracy with respect to past experiments.
Resistive Plate Chamber detectors are largely used in current High Energy Physics experiments, typically operated in avalanche mode with large fractions of Tetrafluoroethane (C2H2F4), a gas recently ...banned by the European Union due to its high Global Warming Potential (GWP). An intense R&D activity is ongoing to improve RPC technology in view of future HEP applications. In the last few years the RPC EcoGas@GIF++ Collaboration has been putting in place a joint effort between the ALICE, ATLAS, CMS, LHCb/SHiP and EP-DT Communities to investigate the performance of present and future RPC generations with eco-friendly gas mixtures. Detectors with different layout and electronics have been operated with ecological gas mixtures, with and without irradiation at the CERN Gamma Irradiation Facility (GIF++). Results of these performance studies together with plans for an aging test campaign are discussed in this article.
Background It is difficult to estimate the diagnostic accuracy of biopsy for prostate cancer because men with negative biopsy do not undergo radical prostatectomy and thus have no confirmation of ...biopsy findings. Methods We performed 18-core needle biopsies on autopsy prostates from 164 men who had no history of prostate cancer. Six-core biopsies were taken from each of the mid peripheral zone (MPZ), the lateral peripheral zone (LPZ), and the central zone (CZ). We tested associations between age and tumor characteristics and analyzed the sensitivity of biopsies at each site. All statistical tests were two-sided. Results Prostate cancer was present in 47 (29%) prostates. Of the 47 cancers detected, 20 were clinically significant according to histologic criteria. Tumor volume was associated with tumor grade (P = .012) and with age (P<.001). The biopsies from the CZ did not detect any cancer that was not present in biopsies of either the MPZ or LPZ. The sensitivity of the biopsies taken from the MPZ and LPZ together (53%, 95% confidence interval CI = 38% to 68%) was therefore the same as that of 18-core biopsies and was superior to that of biopsies of the MPZ alone (30%, 95% CI = 17% to 45%) (P = .003). The sensitivities of biopsies from the MPZ for clinically significant and insignificant cancer were 55% (95% CI = 32% to 77%) and 11% (95% CI = 2% to 29%), respectively, compared with 80% (95% CI = 56% to 94%) and 33% (95% CI = 17% to 54%) for those from the MPZ and LPZ combined. Conclusions The ability to detect prostate cancer was more related to the biopsy site than to the number of biopsy cores taken. The 12-core biopsies, six cores each from the MPZ and LPZ, were most likely to detect the majority of clinically significant cancers but also detected many insignificant cancers. When the six-core biopsies from the CZ were added, no increase in sensitivity was observed.
The production of biodiesel as a fuel in diesel engines greatly increased in recent years and is expected to grow more and more in the near future. Increasing biodiesel consumption requires optimized ...production processes allowing high production capacities, simplified operations, high yields, and the use of more economic feedstocks such as waste oils and fats. However, the latter often contain large amounts of free fatty acids and cannot be processed with the commonly practiced technology based on the use of alkaline catalysts in the homogeneous phase that requires the use of highly refined oil as raw materials. Therefore, the development of processes for low-cost biodiesel production requires the individuation of heterogeneous catalysts that are very efficient in promoting the transesterification reaction also in the presence of free fatty acids and water, allowing the prompt separation of pure glycerol and not requiring expensive purification of this byproduct. In the present contribution, the performances of different heterogeneous catalysts are compared both in the absence and in the presence of free fatty acids. In some cases, the resistance of the catalysts to the presence of water and the eventual deactivating effects after the first use have also been tested. The catalysts considered are both basic and acidic in nature, such as hydrotalcite, MgO, TiO2 grafted on silica, vanadyl phosphate, and different metals-substituted vanadyl phosphate of the type Me(H2O) x VO1- x PO4·2H2O, where Me is a trivalent cation such as Al, Ga, Fe, and Cr and where x = 0.18−0.20. Finally, the understanding of the kinetic behavior of the most stable catalyst TiO2/SiO2 has been deepened.
The technique of nuclear emulsions for high-energy physics experiments is being revived, thanks to the remarkable progress in measurement automation achieved in the past years. The present paper ...describes the features and performances of the
European Scanning System, a last-generation automatic microscope working at a scanning speed of
20
cm
2
/
h
. The system has been developed in the framework of the OPERA experiment, designed to unambigously detect
ν
μ
→
ν
τ
oscillations in nuclear emulsions.
The use of nuclear emulsions in very large physics experiments is now possible thanks to the recent improvements in the industrial production of emulsions and to the development of fast automated ...microscopes. In this paper the hardware performances of the
European Scanning System (ESS) are described. The ESS is a very fast automatic system developed for the mass scanning of the emulsions of the OPERA experiment, which requires microscopes with scanning speeds of
∼
20
cm
2
/
h
in an emulsion volume of
44
μ
m
thickness.
Ustekinumab (UST) is an anti-IL12/23 antibody for the treatment of Crohn's Disease (CD). The aim of this study was to compare the efficacy and safety of UST in a large population-based cohort of CD ...patients who failed previous treatment with other biologics.
194 CD patients (108 males and 86 females, mean age 48 years (range 38-58 years) were retrospectively reviewed. 147 patients were already treated with anti-TNFα (75.8%), and 47 (24.2%) patients were already treated with anti-TNFα and vedolizumab. Concomitant treatment with steroids was present in 177 (91.2%) patients.
At week 12, clinical remission was achieved in 146 (75.2%) patients. After a mean follow-up of 6 months, clinical remission was maintained in 135 (69.6%) patients; at that time, mucosal healing was assessed in 62 (31.9%) patients, and it was achieved in 33 (53.2) patients. Three (1.5%) patients were submitted to surgery. Steroid-free remission was achieved in 115 (59.3%) patients. Both serum C-Reactive Protein and Fecal Calprotectin (FC) levels were significantly reduced with respect to baseline levels during follow-up. A logistic regression, UST therapy as third-line therapy (after both anti-TNFα and vedolizumab), FC >200 µg/g, and HBI ≥8 were significantly associated with lack of remission. Adverse events occurred in 5 (2.6%) patients, and four of them required suspension of treatment.
UST seemed to be really effective and safe in CD patients unresponsive to other biologic treatments, especially when used as second-line treatment.
PDF
