Cherenkov light imaging tests with state-of-the-art solid state photon counter for the CLAS12 RICH detector

A large area ring-imaging Cherenkov detector will be operated for hadron identification in the 3GeV/c to 8GeV/c momentum range at the CLAS12 experiment at the upgraded continuous electron beam accelerator facility of Jefferson Lab. The detector, consisting of aerogel radiator, composite mirrors and photon counters, will be built with a hybrid optics design to allow the detection of Cherenkov light for both forward and large angle hadron tracks. The active area has to be densely packed and highly segmented, covering about 1m2 with pixels of 6mm2, and to allow a time resolution of 1. ns. A technology that can offer a cost-effective solution and low material budget could be Silicon Photomultipliers (SiPM) thanks to their high gain at low bias voltage, fast timing, good single-photoelectron resolution and insensitivity to magnetic fields. An investigation is ongoing on samples of 3×3mm2 SiPM of different micro-cell size to assess the single photon detection capability in the presence of high dark count rate due to thermal generation effects, after-pulses or optical cross-talk and to study the response to the moderate radiation damage expected at CLAS12. In this work, a brief review of the latest and most interesting results from these studies will be shown

Genetic polymorphisms of vitamin D pathway predict antiviral treatment outcome in slow responder naive patients with chronic hepatitis C.

Vitamin D serum levels seem to influence antiviral response in chronic hepatitis C. Vitamin D pathway is controlled by genes presenting functional single nucleotide polymorphisms (SNPs). Data regarding the association between these polymorphisms and the rate of sustained viral response (SVR) following antiviral treatment in chronic hepatitis C virus (HCV) infection are largely incomplete. Aim of this study was to evaluate if the carriage of different SNPs of these genes could influence the rate of SVR in patients treated with interferon plus ribavirin. Two hundred and six HCV positive patients treated with PEG-interferon plus ribavirin were retrospectively evaluated. Polymorphic loci rs7041 G>T and rs4588 C>A of the vitamin D transporter GC-globulin, rs10741657 G>A of the vitamin D 25 hydroxylase CYP2R1 and rs10877012 G>T of vitamin D 1-hydroxylase CYP27B1 were genotyped. A genetic model named VDPFA (vitamin D Pathway Functional Alleles) was constructed considering for each patient the sum (from 0 to 8), derived from every functional allele carried, associated with the achievement of SVR. Three groups were identified: those carrying ≤4 VDPFA (N=108), those carrying 5-6 VDPFA (N=78) and those carrying ≥7 VDPFA (N=20). Significant associations were found between the rates of SVR and the VDPFA value both in all (61/108, 53/78, 17/20, p=0.009) and in 1/4-5 HCV genotypes (17/56, 23/43, 6/8, p=0.003). Moreover in patients who don't achieve rapid viral response (RVR) SVR and VDPFA were found to be in stronger associations in all (12/55, 17/39, 7/9, p<0.001) and in 1/4-5 HCV genotypes (4/41, 12/31, 5/6, p=0.001). VDPFA value ≥7 could aid to select, among RVR negative difficult to treat 1/4-5 HCV genotypes, those achieving SVR. These observations could permit to extend the indication to adopt dual antiviral therapy beyond RVR positivity rule without reducing the chances of SVR

Viral response in relationship with Vitamin D Pathway Functional Alleles (VDPFA).

<div><p><b><i>Panel </i><i>A</i></b> Rates of rapid viral response (RVR), complete early viral response (cEVR), end of treatment viral response (EOT) and sustained viral response (SVR) in relationship with the number of Vitamin D Pathway Functional Alleles (VDPFA) carried. Data refer to all patients. Statistical analysis was performed by means of chi-square test for linear trend.</p> <p><b><i>Panel </i><i>B</i></b> Rates of rapid viral response (RVR), complete early viral response (cEVR), end of treatment viral response (EOT) and sustained viral response (SVR) in relationship with the number of Vitamin D Pathway Functional Alleles (VDPFA) carried. Data refer to difficult to treat HCV genotypes. Statistical analysis was performed by means of chi-square test for linear trend.</p></div

Effect of Vitamin D Pathway Functional Alleles (VDPFA) on antiviral response in RVR negative patients.

<p>Rates of sustained viral response (SVR) in patients not achieving rapid viral response (RVR negative) in relationship with the number of Vitamin D Pathway Functional Alleles (VDPFA) carried. Statistical analysis was performed by means of chi-square test for linear trend.</p

Prevalent use of Combined Prophylaxis of Hepatitis B after liver transplantation in Italy: Results of a national survey in a large cohort

BACKGROUND: Prophylaxis of hepatitis B after liver transplantation with antiviral(s) and immunoglobulins efficiently protect the majority of recipients; however recent experiences suggest a decline of HBsag-positive candidates and the use of hepatitis B immunoglobulin-free schedules. MetHoDs: this national survey evaluated the epidemiology and clinical results of hepatitis B prophylaxis among 10,365 liver transplants performed in 25 years in 13 italian centers. RESULTSː With a percentage of 22, 2260 procedures were performed in HBsAg-positive recipients and 714 out of 1080 anti-HBc-positive grafts were used in HBsag-negative recipients; a total of 2974 patients (29%) were considered at risk of hepatitis B after liver transplantation. similar rates (18% of HBsag-positive candidates and 15% of anti-HBc-positive grafts) were registered in the last collected year. combined prophylaxis with Hepatitis B immunoglobulins remained prevalent among centers and was effective in 96% of HBsag-positive recipients and in 94% of HBsag-negative recipi-ents of anti-HBc-positive grafts.CONCLUSIONS: Data from this survey confirm: the excellent results of combined prophylaxis; the past and persistent use of Hepatitis B immunoglobulin-on and only rare -off prophylactic regimens, in contrast with the newest reports; the increasing use of anti-HBc-positive grafts; the past and present high prevalence of HBsag-positive recipients, due to an increase in candidates with either hepatocellular carcinoma and Hepatitis Delta Virus coinfection in the last years

The LHCb upgrade I

International audienceThe LHCb upgrade represents a major change of the experiment. The detectors have been almost completely renewed to allow running at an instantaneous luminosity five times larger than that of the previous running periods. Readout of all detectors into an all-software trigger is central to the new design, facilitating the reconstruction of events at the maximum LHC interaction rate, and their selection in real time. The experiment's tracking system has been completely upgraded with a new pixel vertex detector, a silicon tracker upstream of the dipole magnet and three scintillating fibre tracking stations downstream of the magnet. The whole photon detection system of the RICH detectors has been renewed and the readout electronics of the calorimeter and muon systems have been fully overhauled. The first stage of the all-software trigger is implemented on a GPU farm. The output of the trigger provides a combination of totally reconstructed physics objects, such as tracks and vertices, ready for final analysis, and of entire events which need further offline reprocessing. This scheme required a complete revision of the computing model and rewriting of the experiment's software

The LHCb upgrade I

International audienceThe LHCb upgrade represents a major change of the experiment. The detectors have been almost completely renewed to allow running at an instantaneous luminosity five times larger than that of the previous running periods. Readout of all detectors into an all-software trigger is central to the new design, facilitating the reconstruction of events at the maximum LHC interaction rate, and their selection in real time. The experiment's tracking system has been completely upgraded with a new pixel vertex detector, a silicon tracker upstream of the dipole magnet and three scintillating fibre tracking stations downstream of the magnet. The whole photon detection system of the RICH detectors has been renewed and the readout electronics of the calorimeter and muon systems have been fully overhauled. The first stage of the all-software trigger is implemented on a GPU farm. The output of the trigger provides a combination of totally reconstructed physics objects, such as tracks and vertices, ready for final analysis, and of entire events which need further offline reprocessing. This scheme required a complete revision of the computing model and rewriting of the experiment's software

The LHCb upgrade I

International audienceThe LHCb upgrade represents a major change of the experiment. The detectors have been almost completely renewed to allow running at an instantaneous luminosity five times larger than that of the previous running periods. Readout of all detectors into an all-software trigger is central to the new design, facilitating the reconstruction of events at the maximum LHC interaction rate, and their selection in real time. The experiment's tracking system has been completely upgraded with a new pixel vertex detector, a silicon tracker upstream of the dipole magnet and three scintillating fibre tracking stations downstream of the magnet. The whole photon detection system of the RICH detectors has been renewed and the readout electronics of the calorimeter and muon systems have been fully overhauled. The first stage of the all-software trigger is implemented on a GPU farm. The output of the trigger provides a combination of totally reconstructed physics objects, such as tracks and vertices, ready for final analysis, and of entire events which need further offline reprocessing. This scheme required a complete revision of the computing model and rewriting of the experiment's software

The LHCb upgrade I

International audienceThe LHCb upgrade represents a major change of the experiment. The detectors have been almost completely renewed to allow running at an instantaneous luminosity five times larger than that of the previous running periods. Readout of all detectors into an all-software trigger is central to the new design, facilitating the reconstruction of events at the maximum LHC interaction rate, and their selection in real time. The experiment's tracking system has been completely upgraded with a new pixel vertex detector, a silicon tracker upstream of the dipole magnet and three scintillating fibre tracking stations downstream of the magnet. The whole photon detection system of the RICH detectors has been renewed and the readout electronics of the calorimeter and muon systems have been fully overhauled. The first stage of the all-software trigger is implemented on a GPU farm. The output of the trigger provides a combination of totally reconstructed physics objects, such as tracks and vertices, ready for final analysis, and of entire events which need further offline reprocessing. This scheme required a complete revision of the computing model and rewriting of the experiment's software