Azimuthal anisotropy of charged jet production in root s(NN)=2.76 TeV Pb-Pb collisions

We present measurements of the azimuthal dependence of charged jet production in central and semi-central root s(NN) = 2.76 TeV Pb-Pb collisions with respect to the second harmonic event plane, quantified as nu(ch)(2) (jet). Jet finding is performed employing the anti-k(T) algorithm with a resolution parameter R = 0.2 using charged tracks from the ALICE tracking system. The contribution of the azimuthal anisotropy of the underlying event is taken into account event-by-event. The remaining (statistical) region-to-region fluctuations are removed on an ensemble basis by unfolding the jet spectra for different event plane orientations independently. Significant non-zero nu(ch)(2) (jet) is observed in semi-central collisions (30-50% centrality) for 20 <p(T)(ch) (jet) <90 GeV/c. The azimuthal dependence of the charged jet production is similar to the dependence observed for jets comprising both charged and neutral fragments, and compatible with measurements of the nu(2) of single charged particles at high p(T). Good agreement between the data and predictions from JEWEL, an event generator simulating parton shower evolution in the presence of a dense QCD medium, is found in semi-central collisions. (C) 2015 CERN for the benefit of the ALICE Collaboration. Published by Elsevier B.V. This is an open access article under the CC BY license (http://creativecommons.org/licenses/by/4.0/).Peer reviewe

Production of He-4 and (4) in Pb-Pb collisions at root(NN)-N-S=2.76 TeV at the LHC

Results on the production of He-4 and (4) nuclei in Pb-Pb collisions at root(NN)-N-S = 2.76 TeV in the rapidity range vertical bar y vertical bar <1, using the ALICE detector, are presented in this paper. The rapidity densities corresponding to 0-10% central events are found to be dN/dy4(He) = (0.8 +/- 0.4 (stat) +/- 0.3 (syst)) x 10(-6) and dN/dy4 = (1.1 +/- 0.4 (stat) +/- 0.2 (syst)) x 10(-6), respectively. This is in agreement with the statistical thermal model expectation assuming the same chemical freeze-out temperature (T-chem = 156 MeV) as for light hadrons. The measured ratio of (4)/He-4 is 1.4 +/- 0.8 (stat) +/- 0.5 (syst). (C) 2018 Published by Elsevier B.V.Peer reviewe

Pseudorapidity and transverse-momentum distributions of charged particles in proton-proton collisions at root s=13 TeV

The pseudorapidity (eta) and transverse-momentum (p(T)) distributions of charged particles produced in proton-proton collisions are measured at the centre-of-mass energy root s = 13 TeV. The pseudorapidity distribution in vertical bar eta vertical bar <1.8 is reported for inelastic events and for events with at least one charged particle in vertical bar eta vertical bar <1. The pseudorapidity density of charged particles produced in the pseudorapidity region vertical bar eta vertical bar <0.5 is 5.31 +/- 0.18 and 6.46 +/- 0.19 for the two event classes, respectively. The transverse-momentum distribution of charged particles is measured in the range 0.15 <p(T) <20 GeV/c and vertical bar eta vertical bar <0.8 for events with at least one charged particle in vertical bar eta vertical bar <1. The evolution of the transverse momentum spectra of charged particles is also investigated as a function of event multiplicity. The results are compared with calculations from PYTHIA and EPOS Monte Carlo generators. (C) 2015 CERN for the benefit of the ALICE Collaboration. Published by Elsevier B.V. This is an open access article under the CC BY license (http://creativecommons.org/licenses/by/4.0/).Peer reviewe

Higher Liver Volume is a Non-Invasive Indicator of Hepatic Reserve in Cirrhotic Patients Undergoing Treatment for Hepatitis C Virus Infection

BACKGROUND: Nearly all patients with hepatitis C virus (HCV) infection can be treated successfully and achieve a virolgical cure; however, cure does not ensure the return of normal liver function. Non-invasive markers are needed to identify patients at high risk for continued liver dysfunction despite HCV cure. OBJECTIVES: To evaluate liver volume, spleen volume, and model for end-stage liver disease (MELD) score prior to treatment as predictors of continued liver dysfunction post-cure. METHODS: Multivariable logistic regression was used to identify factors associated with post-cure liver dysfunction, defined as serum albumin below the lower limit of normal. Liver and spleen volumes were calculated from computed tomography (CT) and magnetic resonance images (MRI). RESULTS: One-predictor logistic regression models revealed that greater pre-treatment liver volume per ideal body weight [odds ratio (OR): 1.2 per mL/kg, p=0.008], lower pre-treatment spleen volume per ideal body weight (OR: 0.89 for every mL/kg, p=0.032), and lower pre-treatment MELD score (OR: 0.56 for every 1 unit increase in MELD score, p=0.002) were significantly related to recovery (albumin normalization). SIGNIFICANCE: Liver volume, spleen volume, and the MELD score may all help to identify high-risk patients

Liver Stiffness Decreases Rapidly in Response to Successful Hepatitis C Treatment and Then Plateaus

<div><p>Background and Aim</p><p>To investigate the impact of a sustained virological response (SVR) to hepatitis C virus (HCV) treatment on liver stiffness (LS).</p><p>Methods</p><p>LS, measured by transient elastography (FibroScan), demographic and laboratory data of patients treated with interferon (IFN)-containing or IFN-free regimens who had an SVR24 (undetectable HCV viral load 24 weeks after the end of treatment) were analyzed using two-tailed paired t-tests, Mann-Whitney Wilcoxon Signed-rank tests and linear regression. Two time intervals were investigated: pre-treatment to SVR24 and SVR24 to the end of follow-up. LS scores ≥ 12.5 kPa indicated LS-defined cirrhosis. A p-value below 0.05 was considered statistically significant.</p><p>Results</p><p>The median age of the patients (n = 100) was 60 years [IQR (interquartile range) 54–64); 72% were male; 60% were Caucasian; and 42% had cirrhosis pre-treatment according to the FibroScan measurement. The median LS score dropped from 10.40 kPa (IQR: 7.25–18.60) pre-treatment to 7.60 kPa (IQR: 5.60–12.38) at SVR24, p <0.01. Among the 42 patients with LS-defined cirrhosis pre-treatment, 25 (60%) of patients still had LS scores ≥ 12.5 kPa at SVR24, indicating the persistence of cirrhosis. The median change in LS was similar in patients receiving IFN-containing and IFN-free regimens: -1.95 kPa (IQR: -5.75 –-0.38) versus -2.40 kPa (IQR: -7.70 –-0.23), p = 0.74. Among 56 patients with a post-SVR24 LS measurement, the LS score changed by an additional -0.90 kPa (IQR: -2.98–0.5) during a median follow-up time of 1.17 (IQR: 0.88–1.63) years, which was not a statistically significant decrease (p = 0.99).</p><p>Conclusions</p><p>LS decreased from pre-treatment to SVR24, but did not decrease significantly during additional follow-up. Earlier treatment may be needed to reduce the burden of liver disease.</p></div

Changes in Liver Stiffness (pre-treatment to SVR24): IFN vs IFN-free Regimens.

<p>Changes in Liver Stiffness (pre-treatment to SVR24): IFN vs IFN-free Regimens.</p

Pre-treatment versus SVR24 liver stiffness.

<p>Comparison of pre-treatment to SVR24 LS in kPa stratified by METAVIR fibrosis stage with (A) depicting median and interquartile ranges for pre-treatment scores and (B) depicting median and interquartile ranges for SVR24 scores. The vertical axis is the liver stiffness in kPa and the horizontal axis is the METAVIR fibrosis stage and the number of patients in each fibrosis stage. The top and bottom boxes represent interquartile ranges (interquartile 1 and interquartile 3 respectively). The lines through the boxes represent median values. The whiskers at the end of the box represent the maximum and minimum values.</p

Estimated Fibrosis Stage using Fibroscan at SVR24 Stratified by the Pre-treatment Stiffness Score.

<p>Estimated Fibrosis Stage using Fibroscan at SVR24 Stratified by the Pre-treatment Stiffness Score.</p

Model of changes in liver stiffness overtime.

<p>This model graph shows a percentage decrease in liver stiffness from pre-treatment to post-SVR24. The initial decline in liver stiffness is most likely due to regression of liver inflammation. After SVR24 there was little change in liver stiffness over time as indicated in <a href="http://www.plosone.org/article/info:doi/10.1371/journal.pone.0159413#pone.0159413.g003" target="_blank">Fig 3</a>.</p