Multiplicity Studies and Effective Energy in ALICE at the LHC

In this work we explore the possibility to perform ``effective energy'' studies in very high energy collisions at the CERN Large Hadron Collider (LHC). In particular, we focus on the possibility to measure in $pp$ collisions the average charged multiplicity as a function of the effective energy with the ALICE experiment, using its capability to measure the energy of the leading baryons with the Zero Degree Calorimeters. Analyses of this kind have been done at lower centre--of--mass energies and have shown that, once the appropriate kinematic variables are chosen, particle production is characterized by universal properties: no matter the nature of the interacting particles, the final states have identical features. Assuming that this universality picture can be extended to {\it ion--ion} collisions, as suggested by recent results from RHIC experiments, a novel approach based on the scaling hypothesis for limiting fragmentation has been used to derive the expected charged event multiplicity in $AA$ interactions at LHC. This leads to scenarios where the multiplicity is significantly lower compared to most of the predictions from the models currently used to describe high energy $AA$ collisions. A mean charged multiplicity of about 1000-2000 per rapidity unit (at $\eta \sim 0$) is expected for the most central $Pb-Pb$ collisions at $\sqrt{s_{NN}} = 5.5 TeV$.Comment: 12 pages, 19 figures. In memory of A. Smirnitski

Study of QGP signatures with the phi->K+K- signal in Pb-Pb ALICE events

The phi->K+K- decay channel in Pb-Pb collisions at LHC is studied through a full simulation of the ALICE detector. The study focuses on possible signatures in this channel of quark-gluon plasma (QGP) formation. On a basis of 10^6 collisions at high centrality some proposed QGP signatures are clearly visible both in K+K- invariant mass and transverse mass distributions. The high significance of this observation appears to reside heavily on the use of the TOF (Time Of Flight) system of ALICE in addition to its central tracking detectors.Comment: 9 pages, 7 figures, to appear in EPJ

How do cardiologists select patients for dual antiplatelet therapy continuation beyond 1 year after a myocardial infarction? Insights from the EYESHOT Post-MI Study

Background: Current guidelines suggest to consider dual antiplatelet therapy (DAPT) continuation for longer than 12 months in selected patients with myocardial infarction (MI). Hypothesis: We sought to assess the criteria used by cardiologists in daily practice to select patients with a history of MI eligible for DAPT continuation beyond 1 year. Methods: We analyzed data from the EYESHOT Post-MI, a prospective, observational, nationwide study aimed to evaluate the management of patients presenting to cardiologists 1 to 3 years from the last MI event. Results: Out of the 1633 post-MI patients enrolled in the study between March and December 2017, 557 (34.1%) were on DAPT at the time of enrolment, and 450 (27.6%) were prescribed DAPT after cardiologist assessment. At multivariate analyses, a percutaneous coronary intervention (PCI) with multiple stents and the presence of peripheral artery disease (PAD) resulted as independent predictors of DAPT continuation, while atrial fibrillation was the only independent predictor of DAPT interruption for patients both at the second and the third year from MI at enrolment and the time of discharge/end of the visit. Conclusions: Risk scores recommended by current guidelines for guiding decisions on DAPT duration are underused and misused in clinical practice. A PCI with multiple stents and a history of PAD resulted as the clinical variables more frequently associated with DAPT continuation beyond 1 year from the index MI

The ALICE experiment at the CERN LHC

ALICE (A Large Ion Collider Experiment) is a general-purpose, heavy-ion detector at the CERN LHC which focuses on QCD, the strong-interaction sector of the Standard Model. It is designed to address the physics of strongly interacting matter and the quark-gluon plasma at extreme values of energy density and temperature in nucleus-nucleus collisions. Besides running with Pb ions, the physics programme includes collisions with lighter ions, lower energy running and dedicated proton-nucleus runs. ALICE will also take data with proton beams at the top LHC energy to collect reference data for the heavy-ion programme and to address several QCD topics for which ALICE is complementary to the other LHC detectors. The ALICE detector has been built by a collaboration including currently over 1000 physicists and engineers from 105 Institutes in 30 countries. Its overall dimensions are 161626 m3 with a total weight of approximately 10 000 t. The experiment consists of 18 different detector systems each with its own specific technology choice and design constraints, driven both by the physics requirements and the experimental conditions expected at LHC. The most stringent design constraint is to cope with the extreme particle multiplicity anticipated in central Pb-Pb collisions. The different subsystems were optimized to provide high-momentum resolution as well as excellent Particle Identification (PID) over a broad range in momentum, up to the highest multiplicities predicted for LHC. This will allow for comprehensive studies of hadrons, electrons, muons, and photons produced in the collision of heavy nuclei. Most detector systems are scheduled to be installed and ready for data taking by mid-2008 when the LHC is scheduled to start operation, with the exception of parts of the Photon Spectrometer (PHOS), Transition Radiation Detector (TRD) and Electro Magnetic Calorimeter (EMCal). These detectors will be completed for the high-luminosity ion run expected in 2010. This paper describes in detail the detector components as installed for the first data taking in the summer of 2008

Drug micro-carriers with a hyaluronic acid corona toward a diffusion-limited aggregation within the vitreous body

Posterior eye segment diseases are treated through monthly intravitreal injections, that evoke serious side effects. A promising approach to reduce injection frequency consists in producing biodegradable microspheres (MPs) releasing the protein in the vitreous body for long times. Moreover, a rational design of these MPs requires a discouraged diffusion/sedimentation within the intravitreal space, which are detrimental for the vision and the control over drug release kinetics. In this work, poly(lactic-co-glycolic acid) (PLGA)-based MPs encapsulating bovine serum albumin (BSA) were coated with hyaluronic acid (HA) at two molecular weights and tested for their release, diffusion and degradation features in simulated vitreous body (SVB). Results indicate that HA corona prolongs MP degradation time and BSA release. Furthermore, HA coating increased the affinity between MPs and SVB, thereby repressing device transport compared to control PLGA MPs. Results hold promise for the possible application of HA-decorated MPs for intravitreal injection of protein drugs

Noninvasive Diagnosis of Incomplete Endovascular Aneurysm Repair: D-Dimero assay to detect type I Endoleaks and nonshrinking aneurisms

Rationale: Persistent endoleaks(EL) due to inadequate stent attachment or fixation, have been generally considered a treatment failure, thus a primary endpoint in long term follow ups, even if most recently the axiom EL-increased AAA volume-rupture has been criticized. Since it has been shown that even patients with a negative early follow up are not exempt from risks for late endoleak formation or rupture , a warning has been raised in that all patients treated with endovascular devices should be carefully followed lifetime. Therefore , non invasive and non expensive tools for detection of an imperfect endograft functioning are needed.Thesis: in presence of a demonstrable peri graft flow and generally in case of an increasing sac volume, active intravascular thrombus formation occurs and specific markers for endogenous fibrinolysis could detect them and alert for further investigation. D \u2013Dimer (D-D) is a plasmin resistant fibrin fragment which , in the diagnosis of intra vascular thrombosis, has shown high specificity ,sensitivity and high negative predictive value. Methods: We analyzed the D -D blood level in 83 patients selected by the following carachteristics:1. affected by AAA, 2.evaluated and treated with endovascular exclusion with AneuRx Endograft, in follow up after an implant with 3. no endoleak and decreasing volume, 4. with type I endolaeks, 5. Type 2 endoleaks, with 6. Invariated or increased or 7. decreased sac maximal diameter.Plasma was drown in correspondence of the TC scan and clinical monitoring relative to which information on AAA where drown. Plasma was frozen and analyzed for D-D through a Latex quantitative test. Results were stratified according to the patient\u2019s clinical stage. Results: D-D values presented a high interpersonal variability with generally width standard deviations. D \u2013D values do not significantly varied among patients with stable AAA and age matched controls ( 238\ub1245 vg/ml vs 421\ub1 400vg/ml, p> 0.05) . D- D values increase significantly (727\ub1 345 vg/ml vs 421\ub1400 vg/ml p<0.05) immediately after treatment (4th p.o. day). Values do not significantly vary at various distance from the procedure if there is no EL and AAA volume decrease or if Type 2 EL were present. D-D values significantly increased (1931\ub1 924 vg/ml, p< 0.005 vs all other groups) in case of Type 1 EL and in case of EL with unmodified or increasing AAA diameters in comparison with EL and decreasing diameters (1177\ub1 773 vg/ml vs 778\ub1466 vg/ml, p< 0.005).Conclusion: elevated D-D may prove to be a useful arker for fixation problems after endovascular repair and may help rule out of type I endoleak, thus excluding patients from unnecessary invasive tests