0000000000927023
AUTHOR
A. Moretti
K− over K+ multiplicity ratio for kaons produced in DIS with a large fraction of the virtual-photon energy
The K$^{-}$ over K$^{+}$ multiplicity ratio is measured in deep-inelastic scattering, for the first time for kaons carrying a large fraction $z$ of the virtual-photon energy. The data were obtained by the COMPASS collaboration using a 160 GeV muon beam and an isoscalar $^6$LiD target. The regime of deep-inelastic scattering is ensured by requiring $Q^2>1$ (GeV/$c)^2$ for the photon virtuality and $W>5$ GeV/$c^2$ for the invariant mass of the produced hadronic system. Kaons are identified in the momentum range from 12 GeV/$c$ to 40 GeV/$c$, thereby restricting the range in Bjorken-$x$ to $0.010.75$. For very large values of $z$, $i.e.$ $z>0.8$, we observe the kaon multiplicity ratio to fall …
Pegylated interferon α plus ribavirin for the treatment of chronic hepatitis C: A multicentre independent study supported by the Italian Drug Agency
a b s t r a c t Background: Data on the efficacy of Peg-interferon/ribavirin therapy for chronic hepatitis C are mostly derived from treatment of selected patients enrolled in clinical trials. This study aimed to assess the effectiveness of Peg-interferon/ribavirin therapy in “real world” chronic hepatitis C patients in Italy. Methods: Independent observational multicentre study including consecutive patients receiving Peginterferon/ribavirin in the 18 months before (retrospective phase) and after (prospective phase) the start of the study. Results: 4176 patients were eligible. The final study population consisted of 2051 patients in the retrospective and 2073 in the prospective phase. Sust…
Contribution of exclusive diffractive processes to the measured azimuthal asymmetries in SIDIS
Hadron leptoproduction in Semi-Inclusive measurements of Deep-Inelastic Scattering (SIDIS) on unpolarised nucleons allows one to get information on the intrinsic transverse momentum of quarks in a nucleon and on the Boer-Mulders function through the measurement of azimuthal modulations in the cross section. These modulations were recently measured by the HERMES experiment at DESY on proton and deuteron targets, and by the COMPASS experiment using the CERN SPS muon beam and a $^6$LiD target. In both cases, the amplitudes of the $\cos\phi_h$ and $\cos 2\phi_h$ modulations show strong kinematic dependences for both positive and negative hadrons. It has been known since some time that the measu…
Swift GRBs: The early afterglow spectral energy distribution
We present the first results of a program to systematically study the optical-to-X-ray spectral energy distribution (SED) of Swift GRB afterglows with known redshift. The goal is to study the properties of the GRB explosion and of the intervening absorbing material. In this report we present the preliminary analysis on 23 afterglows. Thanks to Swift, we could build the SED at early times after the GRB (minutes to hours). We derived the Hydrogen column densities and the spectral slopes from the X-ray spectrum. We then constrained the visual extinction by requiring that the combined optical/X-ray SED is due to synchrotron, namely either a single power law or a broken power law with a slope ch…
Antiproton over proton and K$^-$ over K$^+$ multiplicity ratios at high $z$ in DIS
The $\bar{\rm p} $ over p multiplicity ratio is measured in deep-inelastic scattering for the first time using (anti-) protons carrying a large fraction of the virtual-photon energy, $z>0.5$. The data were obtained by the COMPASS Collaboration using a 160 GeV muon beam impinging on an isoscalar $^6$LiD target. The regime of deep-inelastic scattering is ensured by requiring $Q^2$ > 1 (GeV/$c$)$^2$ for the photon virtuality and $W > 5$ GeV/$c^2$ for the invariant mass of the produced hadronic system. The range in Bjorken-$x$ is restricted to $0.01 < x < 0.40$. Protons and antiprotons are identified in the momentum range $20 ��60$ GeV/$c$. In the whole studied $z$-region, the $\…
GRB 050410 and GRB 050412: are they really dark gamma-ray bursts?
We present a detailed analysis of the prompt and afterglow emission of GRB 050410 and GRB 050412 detected by Swift for which no optical counterpart was observed. The 15-150 keV energy distribution of the GRB 050410 prompt emission shows a peak energy at 53 keV. The XRT light curve of this GRB decays as a power law with a slope of alpha=1.06+/-0.04. The spectrum is well reproduced by an absorbed power law with a spectral index Gamma_x=2.4+/-0.4 and a low energy absorption N_H=4(+3;-2)x10^21 cm^(-2) which is higher than the Galactic value. The 15-150 keV prompt emission in GRB 050412 is modelled with a hard (Gamma=0.7+/-0.2) power law. The XRT light curve follows a broken power law with the f…
The flaring afterglow of GRB 050730
We present a detailed spectral and temporal analysis of Swift and XMM-Newton observations of GRB 050730. The X-ray afterglow of GRB 050730 was found to decline with time with intense flaring activity superimposed. Evidence of flaring activity in the early UVOT optical afterglow, simultaneous with that observed in the X-ray band, was found. Strong spectral evolution in the X-ray energy band during the flaring activity was present.
Undetectable HCV-RNA at treatment-week 8 results in high-sustained virological response in HCV G1 treatment-experienced patients with advanced liver disease: The International Italian/Spanish Boceprevir/Peginterferon/Ribavirin Name Patients Program
In many countries, first-generation protease inhibitors (PIs)/peginterferon/ribavirin (P/R) still represent the only treatment option for HCV-infected patients. Subjects with advanced disease and previous failure to P/R urgently need therapy, but they are under-represented in clinical trials. All treatment-experienced F3/4 Metavir patients who received boceprevir (BOC)+P/R in the Italian-Spanish Name Patient Program have been included in this study. Multivariate logistic regression analysis (MLR) was used to identify baseline and on-treatment predictors of SVR and adverse events (AEs). Four hundred and sixteen patients, mean age 57.7 (range 25-78 years), 70% males, 69.5% (289/416) F4, 14% (…
Longitudinal double-spin asymmetry A1p and spin-dependent structure function g1p of the proton at small values of x and Q2
Abstract We present a precise measurement of the proton longitudinal double-spin asymmetry A 1 p and the proton spin-dependent structure function g 1 p at photon virtualities 0.006 ( GeV / c ) 2 Q 2 1 ( GeV / c ) 2 in the Bjorken x range of 4 × 10 − 5 x 4 × 10 − 2 . The results are based on data collected by the COMPASS Collaboration at CERN using muon beam energies of 160 GeV and 200 GeV . The statistical precision is more than tenfold better than that of the previous measurement in this region. In the whole range of x , the measured values of A 1 p and g 1 p are found to be positive. It is for the first time that spin effects are found at such low values of x .
Detection of Babesia bovis and B. bigemina in Dama dama
Transverse extension of partons in the proton probed in the sea-quark range by measuring the DVCS cross section
Physics letters / B B793, 188-194 (2019). doi:10.1016/j.physletb.2019.04.038
Corrigendum to “Transverse extension of partons in the proton probed in the sea-quark range by measuring the DVCS cross section” [Phys. Lett. B 793 (2019) 188]
Physics letters / B B 800, 135129 (2020). doi:10.1016/j.physletb.2019.135129
Rest frame light curves of Swift GRBs
Measurement of the cross section for hard exclusive π0 muoproduction on the proton
Physics letters / B B805, 135454 (2020). doi:10.1016/j.physletb.2020.135454
COVID-19: opinions and behavior of Italian general population during the first epidemic phase
Background and aim: On January 9, 2020, the World Health Organization (WHO) declared that Chinese health authorities had identified a new coronavirus strain never before isolated in humans, the 2019-nCoV later redefined SARS-CoV-2, that still today represent a public health problem. The present survey started on 10 February 2020 with the aim of a) assessing the risk perception in healthcare workers and young students, following the evolution of attitudes, perception and knowledge over time, b) provide useful information to the general population during survey. Results: A study sample consisting of 4116 Italian in-dividuals of both sexes was enrolled. High levels of risk perception, low perc…
Pile-up correction for the Swift-XRT observations in WT mode
The detector at the focal plane of the Swift X-ray Telescope (XRT) supports four readout modes, automatically changed on board, to cover the dynamical range of fluxes and rapid variability expected from GRB afterglows. The Windowed Timing (WT) mode is used for sources with flux higher than a few mCrab and is obtained by compressing 10 rows into a single row, and then reading out only the central 200 columns of the CCD. Point sources with a rate above ~300 c/s produce severe pile-up in the central region of the Point Spread Function. This paper presents three methods to correct the effects of the pile-up in WT mode. On ground calibration results and data from the very bright GRB 060124 are u…
Inspiratory Effort and Respiratory Mechanics in Patients with Acute Exacerbation of Idiopathic Pulmonary fibrosis: A Preliminary Matched Control Study.
Background: Patients with acute exacerbation of idiopathic pulmonary fibrosis (AE-IPF) may experience severe acute respiratory failure, even requiring ventilatory assistance. Physiological data on lung mechanics during these events are lacking. Methods: Patients with AE-IPF admitted to Respiratory Intensive Care Unit to receive non-invasive ventilation (NIV) were retrospectively analyzed. Esophageal pressure swing (ΔPes) and respiratory mechanics before and after 2 hours of NIV were collected as primary outcome. The correlation between positive end-expiratory pressure (PEEP) levels and changes of in dynamic compliance (dynCRS) and PaO2/FiO2 ratio was assessed. Further, an exploratory compar…
Transverse-momentum-dependent Multiplicities of Charged Hadrons in Muon-Deuteron Deep Inelastic Scattering
A semi-inclusive measurement of charged hadron multiplicities in deep inelastic muon scattering off an isoscalar target was performed using data collected by the COMPASS Collaboration at CERN. The following kinematic domain is covered by the data: photon virtuality $Q^{2}>1$ (GeV/$c$)$^2$, invariant mass of the hadronic system $W > 5$ GeV/$c^2$, Bjorken scaling variable in the range $0.003 < x < 0.4$, fraction of the virtual photon energy carried by the hadron in the range $0.2 < z < 0.8$, square of the hadron transverse momentum with respect to the virtual photon direction in the range 0.02 (GeV/$c)^2 < P_{\rm{hT}}^{2} < 3$ (GeV/$c$)$^2$. The multiplicities are pres…
Triangle Singularity as the Origin of the a1(1420)
The COMPASS Collaboration experiment recently discovered a new isovector resonancelike signal with axial-vector quantum numbers, the a 1 ( 1420 ) , decaying to f 0 ( 980 ) π . With a mass too close to and a width smaller than the axial-vector ground state a 1 ( 1260 ) , it was immediately interpreted as a new light exotic meson, similar to the X , Y , Z states in the hidden-charm sector. We show that a resonancelike signal fully matching the experimental data is produced by the decay of the a 1 ( 1260 ) resonance into K * ( → K π ) K ¯ and subsequent rescattering through a triangle singularity into the coupled f 0 ( 980 ) π channel. The amplitude for this process is calculated using a new a…
The short GRB 051210 observed by Swift
We report on the short GRB051210 detected by the Swift-BAT. The light curve, on which we focus mainly, shows a hint of extended emission in the BAT energy range, a steep decay of the X-ray emission, without any flattening or break, and two small flares in the first 300 sec. The emission fades out after ~1000 s.
Attributes of flares in Gamma Ray Bursts: sample I
We discuss some of the preliminary results and findings derived from the analysis of a first sample of flares detected by the XRT on board Swift. The analysis shows that the morphology of flares is the one we expect from the collision of ultra-relativistic shells as it happens during the internal shock model proposed by Rees and Meszaros in 1994. Furthermore the Delta(t)/t ratio and the decay-time to rise-time ratio have mean values that are in good agreement with the values observed in the prompt emission pulses that are believed to originate from internal shocks. The conclusion is that the flare analysis favors the internal shock as due to shells that have been ejected by the central engi…
GRB 050904 at redshift 6.3: observations of the oldest cosmic explosion after the Big Bang
We present optical and near-infrared observations of the afterglow of the gamma-ray burst GRB 050904. We derive a photometric redshift z = 6.3, estimated from the presence of the Lyman break falling between the I and J filters. This is by far the most distant GRB known to date. Its isotropic-equivalent energy is 3.4x10^53 erg in the rest-frame 110-1100 keV energy band. Despite the high redshift, both the prompt and the afterglow emission are not peculiar with respect to other GRBs. We find a break in the J-band light curve at t_b = 2.6 +- 1.0 d (observer frame). If we assume this is the jet break, we derive a beaming-corrected energy E_gamma = (4-12)x10^51 erg. This limit shows that GRB 050…
Efficacy and safety of Boceprevir-based therapy in HCVG1 treatment-experienced patients with advanced fibrosis/cirrhosis: Italian NPP survey
S. Bruno1, S. Bollani1, A.L. Zignego2, V. Calvaruso3, C. Magni4, S. Landonio4, M. Rizzetto5, A. Ciancio5, A. Mangia6, V. Piazzolla6, M. Caremani7, S. Piovesan8, L. Cavalletto9, S. Babudieri9, A. Moretti 10, C. Colletta11, M. Massari12, S. Fangazio13, F. Mazzotta14, L. Muratori15, A.E. Colombo16, M. Zuin17, A. Traverso18, T. Santantonio19, F. Farina20, E. Marchionne21, G. Serviddio22, M. Russello23, A. Licata24, A. Craxi3, V. Di Marco3 1 Internal Medicine, AO Fatebenefratelli e Oftalmico, Milano, Italy 2 Internal Medicine, Universita di Firenze, Italy 3 Gastroenterology, Universita di Palermo, Italy 4 Infectiuos Diseases, Ospedale Sacco, Milano, Italy 5 Gastroenterology, Universita di Torino…
Children with special health care needs attending emergency department in Italy: analysis of 3479 cases
Abstract Background Although children with special health care needs (CSHCN) represent a minority of the population, they go through more hospitalizations, more admissions to the Emergency Department (ED), and receive a major number of medical prescriptions, in comparison to general pediatric population. Objectives of the study were to determine the reasons for admission to the ED in Italian CSHCN, and to describe the association between patient’s demographic data, clinical history, and health services requirements. Methods Ad hoc web site was created to collect retrospective data of 3479 visits of CSHCN to the ED in 58 Italian Hospitals. Results Seventy-two percent of patients admitted to …
Multiclass HCV resistance to direct-acting antiviral failure in real-life patients advocates for tailored second-line therapies
Background & Aims: Despite the excellent efficacy of direct-acting antivirals (DAA) reported in clinical trials, virological failures can occur, often associated with the development of resistance-associated substitutions (RASs). This study aimed to characterize the presence of clinically relevant RASs to all classes in real-life DAA failures. Methods: Of the 200 virological failures that were analyzed in 197 DAA-treated patients, 89 with pegylated-interferon+ribavirin (PegIFN+RBV) and 111 without (HCV-1a/1b/1g/2/3/4=58/83/1/6/24/25; 56.8% treatment experienced; 65.5% cirrhotic) were observed. Sanger sequencing of NS3/NS5A/NS5B was performed by home-made protocols, at failure (N= 200) and w…