The thermodynamic behavior of QCD matter at high temperature is currently studied by lattice QCD theory. The main features are the fast rise of the energy density \(\epsilon\) around the critical ...temperature \(T_c\) and the large trace anomaly of the energy momentum tensor \(< \Theta_\mu^\mu >=\epsilon - 3 P\) which hints at a strongly interacting system. Such features can be accounted for by employing a massive quasi-particle model with a temperature-dependent bag constant. Recent lattice QCD calculations with physical quark masses by the Wuppertal-Budapest group have shown a slower increase of \(\epsilon\) and a smaller \(<\Theta_\mu^\mu>\) peak with respect to previous results from the hotQCD collaboration. We investigate the implications of such differences from the point of view of a quasi-particle model, also discussing light and strange quark number susceptibilities. Furthermore, we predict the impact of these discrepancies on the temperature-dependence of the transport properties of matter, like the shear and bulk viscosities.
The two key observables related to heavy quarks that have been measured in RHIC and LHC energies are the nuclear suppression factor \(R_{AA}\) and the elliptic flow \(v_2\). Simultaneous description ...of these two observables is a top challenge for all the existing models. We have highlighted how a consistent combination of four ingredients i.e the temperature dependence of the energy loss, full solution of the Boltzmann collision integral for the momentum evolution of heavy quark, hadronization by coalescence, then the hadronic rescattering, responsible to address a large part of such a puzzle. We have considered four different models to evaluate the temperature dependence of drag coefficients of the heavy quark in QGP. All these four different models are set to reproduce the same \(R_{AA}\) as of the experiments. We have shown that for the same \(R_{AA}\), the \(v_2\) could be quite different depending on the interaction dynamics as well as other ingredients.
Heavy quark \(R_{AA}\) and \(v_2\) have been calculated at RHIC energy considering initial conditions with and without pre-equilibrium phase to highlight the effect of the latter on heavy quark ...observables. The momentum evolution of the heavy quark has been studied by means of the Boltzmann transport equation. To model the pre-equilibrium phase we have used the KLN initial condition. We have found that the pre-equilibrium phase impacts the \(R_{AA}\) of about 20-25 \(\%\) whereas the impact on \(v_2\) is very negligible. We have also calculated heavy quark \(R_{AA}\) and \(v_2\) in the case of initializations with early thermalized quark-gluon plasma. We have checked that the particular form of the initial spectrum is not very important for \(R_{AA}\), the larger energy density being more important. In fact, comparing the results obtained within the two initializations we have found that one can mimic the impact of the pre-equilibrium phase using a early thermalized QGP medium.
The heavy quarks constitutes a unique probe of the quark-gluon plasma properties. Both at RHIC and LHC energies a puzzling relation between the nuclear modification factor \(R_{AA}(p_T)\) and the ...elliptic flow \(v_2(p_T)\) has been observed which challenged all the existing models, especially for D mesons. We discuss how the temperature dependence of the heavy quark drag coefficient is responsible for a large part of such a puzzle. In particular, we have considered four different models to evaluate the temperature dependence of drag and diffusion coefficients propagating through a quark gluon plasma (QGP). All the four different models are set to reproduce the same \(R_{AA}(p_T)\) observed in experiments at RHIC and LHC energy. We point out that for the same \(R_{AA}(p_T)\) one can generate 2-3 times more \(v_2\) depending on the temperature dependence of the heavy quark drag coefficient. A non-decreasing drag coefficient as \( T \rightarrow\ T_c \,\) is a major ingredient for a simultaneous description of \(R_{AA}(p_T)\) and \(v_2(p_T)\).
In this talk we review, the quasiparticle description of the hot Yang-Mills
theories, in which the quasiparticles propagate in (and interact with) a
background field related to Z(N)-lines. We compare ...the present description with
a more common one in which the effects of the Z(N)-lines are neglected. We show
that it is possible to take into account the nonperturbative effects at the
confinement transition temperature even without a divergent quasiparticle mass.
One of the primary aims of the ongoing nuclear collisions at Relativistic Heavy Ion Collider (RHIC) and Large Hadron Collider (LHC) energies is to create a Quark Gluon Plasma (QGP). The heavy quarks ...constitutes a unique probe of the QGP properties. Both at RHIC and LHC energies a puzzling relation between the nuclear modification factor \(R_{AA}(p_T)\) and the elliptic flow \(v_2(p_T)\) related to heavy quark has been observed which challenged all the existing models.\\ We discuss how the temperature dependence of the heavy quark drag coefficient can address for a large part of such a puzzle. We have considered four different models to evaluate the temperature dependence of drag and diffusion coefficients propagating through a quark gluon plasma (QGP). All the four different models are set to reproduce the same \(R_{AA}(p_T)\) experimentally observed at RHIC energy. We have found that for the same \(R_{AA}(p_T)\) one can generate \(2-3\) times more \(v_{2}\) depending on the temperature dependence of the heavy quark drag coefficient.
In this talk we review, the quasiparticle description of the hot Yang-Mills theories, in which the quasiparticles propagate in (and interact with) a background field related to Z(N)-lines. We compare ...the present description with a more common one in which the effects of the Z(N)-lines are neglected. We show that it is possible to take into account the nonperturbative effects at the confinement transition temperature even without a divergent quasiparticle mass.
Some case reports suggest that protein C zymogen supplementation may improve the outcome of patients with congenital or acquired protein C deficiency, such as sepsis-induced purpura fulminans. We ...describe the case report of a patient suffering from meningitis who developed a bleeding complication after recombinant human activated protein C administration and was successfully treated without any further bleeding complication with protein C concentrate. Protein C concentrate can be considered in adult patients with meningitis, even if at risk or in the presence of bleeding.
Introduction. In many countries the demand for intensive care beds exceeds their availability. The Medical Emergency Team (MET) can manage critically ill patients outside the intensive care unit ...(ICU). Hospital mortality rate for patients admitted to general wards and assisted by the MET was never compared to the predicted mortality for the same group of patients in an ICU setting. Methods. Single-centre, prospective, observational study on consecutive adult patients assisted by the MET in all general wards and in the Emergency Department of a 1100-bed teaching Hospital. Patients with a 'do-not-attempt-resuscitation' decision were excluded. Results. Eighty-two consecutive patients were included. Observed hospital mortality was 34.1% (28 patients), while the Simplified Acute Physiology Score II (SAPS II) predicted a mortality for the first MET visit of 17% (p=0.02). Patients transferred to an ICU, but not during the first MET evaluation (delayed ICU admission), had worse than predicted outcomes, while patients immediately transferred to an ICU showed hospital mortality similar to the predicted one. The fifty patients treated for acute respiratory failure (especially those with pneumonia - 12 patients) had the worst observed/predicted hospital mortality ratio (3.0 for acute respiratory failure, p=0.02; 8.06, p=0.03 for pneumonia patients). Conclusions. Critically ill patients who remained in general wards or who were admitted to the ICU with some delay had markedly higher hospital mortality than the SAPS II predicted hospital mortality, even if they were assisted by the MET.
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