Strangeness production within Parton-Hadron-String Dynamics (PHSD)

The Parton-Hadron-String Dynamics (PHSD) transport approach consistently simulates the full evolution of a relativistic heavy-ion collision from the initial hard scatterings string formation through the dynamical deconfinement phase transition to the quark gluon plasma (QGP), to the hadronization and to subsequent interactions in the hadronic phase. The transport theoretical description of quarks and gluons is based on a dynamical quasiparticle model for partons matched to reproduce recent lattice QCD results in thermodynamic equilibrium. The transition from partonic to hadronic degrees of freedom is described by covariant transition rates for the fusion of quark-antiquark pairs or three quarks (antiquarks). Studying Pb+Pb reactions from 40 to 158 A GeV, we find that at most 40% of the collision energy is stored in the dynamics of the partons. This implies that a large fraction of non-partonic, i.e. hadronic or string-like matter, which can be viewed as a hadronic corona, is present in these reactions, thus neither hadronic nor purely partonic models can be employed to extract physical conclusions in comparing model results with data. On the other hand, comparing the PHSD results to those of the Hadron-String Dynamics (HSD) approach without the phase transition to QGP, we observe that the existence of the partonic phase has a sizeable influence on the transverse mass distribution of final kaons due to the repulsive partonic mean fields and initial partonic scattering. Furthermore, we find a significant effect of the QGP on the production of multi-strange antibaryons due to a slightly enhanced s+sbar pair production in the partonic phase from massive time-like gluon decay and to a more abundant formation of strange antibaryons in the hadronization process.Comment: Talk given at the International Conference Strangeness in Quark Matter 2009 (SQM 09

Is soft physics entropy driven?

The soft physics, pT < 2 GeV/c, observables at both RHIC and the SPS have now been mapped out in quite specific detail. From these results there is mounting evidence that this regime is primarily driven by the multiplicity per unit rapidity, dNch/deta. This suggests that the entropy of the system alone is the underlying driving force for many of the global observables measured in heavy-ion collisions. That this is the case and there is an apparent independence on collision energy is surprising. I present the evidence for this multiplicity scaling and use it to make some extremely naive predictions for the soft sector results at the LHC.Comment: Proceedings of Hot Quarks 2006. 8 figures, 6 page

Design and test of the final ALICE SDD CARLOS end ladder board

The paper presents the design and test of the final prototype of the CARLOS (Compression And Run Length Encoding Subsystem) end ladder board that is going to be used in the ALICE experiment at CERN. This board is able to compress data coming from one Silicon Drift Detector (SDD) front-end electronics and to send them towards the data concentrator card CARLOSrx in counting room via a 800 Mb/s optical link. The board design faces several constraints, mainly size (54x49 mm) and radiation tolerance: for this reason the board contains several CERN developed ASICs. A test setup has been realized for selecting the good devices among the 500 cards already produced

Is Anomalous Production of Omega and anti-Omega Evidence for Disoriented Chiral Condensates?

No conventional picture of nucleus-nucleus collisions has yet been able to explain the abundance of Omega and anti-Omega hyperons in central collisions between Pb nuclei at 158 A GeV at the CERN SPS. We argue that this is evidence that they are produced as topological defects arising from the formation of disoriented chiral condensates (DCC) with an average domain size of about 2 fm.Comment: version 2 containing formulas, accepted by PR

Recent Results on Strangeness Production at RHIC

Due to its large acceptance, the STAR experiment has acquired a wealth of data on strangeness production for a variety of collisions systems and energies, from p+p to Au+Au. By using the yields and spectra, we address the evolution of the bulk system, including strangeness enhancement and the flavour dependence of radial and elliptic flow. Utilising the fact that we can identify strange baryons and mesons, we investigate different hadronization mechanisms in the intermediate and high p$_{T}$ regions. The ratios of the particle yields, measured to high p$_{T}$, are used to further investigate the range and applicability of the previously reported anomalous baryon production. We also study two-particle azimuthal correlations of identified particles in order to investigate any flavour dependence of jet fragmentation in the available p$_{T}$ range. Data was presented for a number of different collision systems and energies.Comment: Proceedings of SQM'06 Conference, LA, 2006 (submitted to J. Phys. G

an 8-year multi-centre observational study

Background Malaria remains one of the most serious infections for travellers to tropical countries. Due to the lack of harmonized guidelines a large variety of treatment regimens is used in Europe to treat severe malaria. Methods The European Network for Tropical Medicine and Travel Health (TropNet) conducted an 8-year, multicentre, observational study to analyse epidemiology, treatment practices and outcomes of severe malaria in its member sites across Europe. Physicians at participating TropNet centres were asked to report pseudonymized retrospective data from all patients treated at their centre for microscopically confirmed severe Plasmodium falciparum malaria according to the 2006 WHO criteria. Results From 2006 to 2014 a total of 185 patients with severe malaria treated in 12 European countries were included. Three patients died, resulting in a 28-day survival rate of 98.4%. The majority of infections were acquired in West Africa (109/185, 59%). The proportion of patients treated with intravenous artesunate increased from 27% in 2006 to 60% in 2013. Altogether, 56 different combinations of intravenous and oral drugs were used across 28 study centres. The risk of acute renal failure (36 vs 17% p = 0.04) or cerebral malaria (54 vs 20%, p = 0.001) was significantly higher in patients ≥60 years than in younger patients. Respiratory distress with the need for mechanical ventilation was significantly associated with the risk of death in the study population (13 vs 0%, p = 0.001). Post-artemisinin delayed haemolysis was reported in 19/70 (27%) patients treated with intravenous artesunate. Conclusion The majority of patients with severe malaria in this study were tourists or migrants acquiring the infection in West Africa. Intravenous artesunate is increasingly used for treatment of severe malaria in many European treatment centres and can be given safely to European patients with severe malaria. Patients treated with intravenous artesunate should be followed up to detect and manage late haemolytic events

Strangeness enhancements at central rapidity in 40 A GeV/c Pb-Pb collisions

Results are presented on neutral kaon, hyperon and antihyperon production in Pb-Pb and p-Be interactions at 40 GeV/c per nucleon. The enhancement pattern follows the same hierarchy as seen in the higher energy data - the enhancement increases with the strangeness content of the hyperons and with the centrality of collision. The centrality dependence of the Pb-Pb yields and enhancements is steeper at 40 than at 158 A GeV/c. The energy dependence of strangeness enhancements at mid-rapidity is discussed.Comment: 15 pages, 10 figures and 3 tables. Presented at International Conference on Strangeness in Quark Matter (SQM2009), Buzios, Rio de Janeiro, Brazil, 27 Sept - 2 Oct 2009. Submitted to J.Phys.G: Nucl.Part.Phys, one reference adde

Strangeness and Quark Gluon Plasma

A brief summary of strangeness mile stones is followed by a chemical non-equilibrium statistical hadronization analysis of strangeness results at SPS and RHIC. Strange particle production in AA interactions at \sqrt{s_{NN}}\ge 8.6 GeV can be understood consistently as originating from the deconfined quark--gluon plasma in a sudden hadronization process. Onset of QGP formation as function of energy is placed in the beam energy interval 10--30A GeV/c. Strangeness anomalies at LHC are described.Comment: 30 pages including numerouse figures, tables. Opening Lecture: Strangeness and Quark Gluon Plasma -- what has been learned so far and where do we go at SQM2003, North Carolina, March 2003, submitted to J. Phys.

Adherence in HIV-positive patients treated with single-tablet regimens and multi-pill regimens: findings from the COMPACT study

The use of Combination AntiRetroviral Therapy (cART) has decreased the morbidity and mortality of patients infected with HIV. However, adherence to cART remains crucial to prevent virological failure and disease progression. The aim of this study was to assess adherence to treatment among patients treated with Single Tablet Regimen (STR) or with multi-pill regimens based on Protease Inhibitors (PI), Non-Nucleoside Reverse-Transcriptase Inhibitors (NNRTI), or raltegravir (RAL). An observational retrospective cohort analysis based on administrative and clinical databases was conducted at the National Institute for Infectious Diseases (Rome, Italy). HIV-positive patients treated with a cART between Jan 1st, 2008&#x2013;Dec 31st, 2010 were included. Patients were followed-up for one year since the first prescription during the inclusion period or up to death or switch of at least one drug of the regimen. Adherence and selective non-adherence (days without backbone or 3rd drug) were calculated using pharmacy refill compliance [1]. cART regimens were classified based on number of daily pills (STR vs multi-pill regimen) and on type of third drug. Viral Load (VL) and CD4 cell counts at the end of the follow-up were evaluated. A total of 1,604 patients were analyzed, 70.0% male, age 45.0&#x00B1;8.7, 14.3% newly treated. Patients on STR were 159 (9.9%), PI 878 (54.7%), NNRTI 523 (32.6%), RAL 44 (2.7%). Presence of at least one AIDS-defining conditions (according to Centers for Disease Control classification) was 30% in the STR group, 34% PI, 26% NNRTI, 34% RAL (p=n.s.). Adherence was 80.4&#x00B1;14.7% for STR, 71.8&#x00B1;21.8% PI, 77.1&#x00B1;20.3% NNRTI, 74.0&#x00B1;22.4% RAL. Selective non-adherence was 5.5% (18 days) PI, 2.8% (8 days) NNRTI, 12.5% (43 days) RAL (Figure 1). At the end of the follow-up, VL/CD4 values were available among 709 patients (44%); CD4 count &#x003E;500 cell/mm3 was observed among 61% of patients on STR, 44% PI, 48% NNRTI, 42% RAL and VL &#60; 50 copies/ml was observed among 96% of patients on STR, 78% PI, 88% NNRTI, 87% RAL. Interruptions in cART refill remain a relevant problem across all cART regimens. Patients on STR displayed a higher adherence rate compared to multi-pill regimes (PI, NNRTI, and RAL), primarily due to lack of selective non-adherence. Patients on STR experienced also higher rates of VL &#60; 50 and CD4 &#x003E; 500. The use of an STR regimen appears an effective therapeutic option to avoid selective non-adherence and, consequently, to prevent virological failure and disease progression