University of Ioannina

About: University of Ioannina is a education organization based out in Ioannina, Greece. It is known for research contribution in the topics: Population & Large Hadron Collider. The organization has 7654 authors who have published 20594 publications receiving 671560 citations. The organization is also known as: Panepistimio Ioanninon.

Prompt and non-prompt J/ψ production in pp collisions at √s = 7 TeV

Abstract: The production of J/psi mesons is studied in pp collisions at sqrt(s)=7 TeV with the CMS experiment at the LHC. The measurement is based on a dimuon sample corresponding to an integrated luminosity of 314 inverse nanobarns. The J/psi differential cross section is determined, as a function of the J/psi transverse momentum, in three rapidity ranges. A fit to the decay length distribution is used to separate the prompt from the non-prompt (b hadron to J/psi) component. Integrated over J/psi transverse momentum from 6.5 to 30 GeV/c and over rapidity in the range |y| < 2.4, the measured cross sections, times the dimuon decay branching fraction, are 70.9 \pm 2.1 (stat.) \pm 3.0 (syst.) \pm 7.8(luminosity) nb for prompt J/psi mesons assuming unpolarized production and 26.0 \pm 1.4 (stat.) \pm 1.6 (syst.) \pm 2.9 (luminosity) nb for J/psi mesons from b-hadron decays.

Tension and constraints on modified gravity parametrizations of $G_{\textrm{eff}}(z)$ from growth rate and Planck data

Abstract: We construct an updated and extended compilation of growth-rate data based on recent redshift-space distortion measurements. The data set consists of 34 data points and includes corrections for model dependence. In order to minimize overlap and maximize the independence of the data points, we also construct a subsample of this compilation (a ``gold'' growth data set) which consists of 18 data points. We test the consistency of this data set with the best-fit $\mathrm{Planck}15/\mathrm{\ensuremath{\Lambda}}\mathrm{CDM}$ parameters in the context of General Relativity using the evolution equation for the growth factor $\ensuremath{\delta}(a)$ with a $w\mathrm{CDM}$ background. We find tension at the $\ensuremath{\sim}3\ensuremath{\sigma}$ level between the best-fit parameters $w$ (the dark energy equation of state), ${\mathrm{\ensuremath{\Omega}}}_{0m}$ (the matter density parameter), and ${\ensuremath{\sigma}}_{8}$ (the matter power spectrum normalization on scales $8{h}^{\ensuremath{-}1}\text{ }\text{ }\mathrm{Mpc}$) and the corresponding $\mathrm{Planck}15/\mathrm{\ensuremath{\Lambda}}\mathrm{CDM}$ parameters ($w=\ensuremath{-}1$, ${\mathrm{\ensuremath{\Omega}}}_{0m}=0.315$, and ${\ensuremath{\sigma}}_{8}=0.831$). We show that the tension disappears if we allow for evolution of the effective Newton constant, parametrized as ${G}_{\mathrm{eff}}(a)/{G}_{\mathrm{N}}=1+{g}_{a}(1\ensuremath{-}a{)}^{n}\ensuremath{-}{g}_{a}(1\ensuremath{-}a{)}^{2n}$ with $n\ensuremath{\ge}2$ where ${g}_{a}$ and $n$ are parameters of the model, $a$ is the scale factor, and $z=1/a\ensuremath{-}1$ is the redshift. This parametrization satisfies three important criteria: a) positive energy of the graviton (${G}_{\mathrm{eff}}g0$), b) consistency with big bang nucleosynthesis constraints (${G}_{\mathrm{eff}}(a\ensuremath{\ll}1)/{G}_{\mathrm{N}}=1$), and c) consistency with Solar System tests (${G}_{\mathrm{eff}}(a=1)/{G}_{\mathrm{N}}=1$ and ${G}_{\mathrm{eff}}^{\ensuremath{'}}(a=1)/{G}_{\mathrm{N}}=0$). We show that the best-fit form of ${G}_{\mathrm{eff}}(z)$ obtained from the growth data corresponds to weakening gravity at recent redshifts (decreasing function of $z$), and we demonstrate that this behavior is not consistent with any scalar-tensor Lagrangian with a real scalar field. Finally, we use MGCAMB to find the best-fit ${G}_{\mathrm{eff}}(z)$ obtained from the Planck cosmic microwave background power spectrum on large angular scales and show that it is a mildly increasing function of $z$, in $3\ensuremath{\sigma}$ tension with the corresponding decreasing best-fit ${G}_{\mathrm{eff}}(z)$ obtained from the growth data.

Multivariate and network meta-analysis of multiple outcomes and multiple treatments: rationale, concepts, and examples

Abstract: Organisations such as the National Institute for Health and Care Excellence require the synthesis of evidence from existing studies to inform their decisions—for example, about the best available treatments with respect to multiple efficacy and safety outcomes. However, relevant studies may not provide direct evidence about all the treatments or outcomes of interest. Multivariate and network meta-analysis methods provide a framework to address this, using correlated or indirect evidence from such studies alongside any direct evidence. In this article, the authors describe the key concepts and assumptions of these methods, outline how correlated and indirect evidence arises, and illustrate the contribution of such evidence in real clinical examples involving multiple outcomes and multiple treatments

Kounis syndrome: a new twist on an old disease

Abstract: Kounis syndrome is the concurrence of acute coronary syndromes with conditions associated with mast cell activation, such as allergies or hypersensitivity and anaphylactic or anaphylactoid insults that can involve other interrelated and interacting inflammatory cells behaving as a ‘ball of thread’. It is caused by inflammatory mediators such as neutral proteases including tryptase and chymase, arachidonic acid products, histamine, platelet activating factor and a variety of cytokines and chemokines released during the activation process. Platelets with FCeRI and FCeRII receptors also participate in the above cascade. Vasospastic allergic angina, allergic myocardial infarction and stent thrombosis with occluding thrombus infiltrated by eosinophils and/or mast cells constitute the three reported variants of this syndrome. Kounis syndrome is a ubiquitus disease that represents a magnificent natural paradigm and nature’s own experiment, in a final trigger pathway implicated in cases of coronary artery spasm a...