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Hybrid Monte Carlo simulation of four flavour QCD at finite temperature

In this talk I present results obtained by the MTc collaboration. We are performing an extensive numerical study of the finite temperature phase transition in lattice QCD with four flavours of staggered fermions. Here we report results for quark mass mq/T = 0.2 and preliminary data for mq/T = 0.08, obtained on 8 × 123 and 8 × 163 lattices, respectively, by using the hybrid Monte Carlo method. In a

Performance of top-quark and W -boson tagging with ATLAS in Run 2 of the LHC

The performance of identification algorithms (“taggers”) for hadronically decaying top quarks and W bosons in pp collisions at s = 13 TeV recorded by the ATLAS experiment at the Large Hadron Collider is presented. A set of techniques based on jet shape observables are studied to determine a set of optimal cut-based taggers for use in physics analyses. The studies are extended to assess the utility

Quantitative MR measurements of regional and global left ventricular function and strain after intramyocardial transfer of VM202 into infarcted swine myocardium

Previous studies have shown the beneficial effects of the hepatocyte growth factor (HGF) gene on myocardial perfusion and infarction size but not on the regional strain in relationship to global left ventricular function. A noninvasive magnetic resonance (MR) study was performed to determine the effect of a new HGF gene, VM202, expressing two isoforms of HGF, on regional and global left ventricula

The correlation lengths and the order of the phase transition in three-dimensional Z 3 symmetric models

We present a high statistics Monte Carlo investigation of three-dimensional Z 3 symmetric models, which are related to SU(3) pure gauge theory at finite temperature. From the finite size scaling behaviour of bulk properties and the existence of metastable states, we conclude that these models exhibit a first-order phase transition. We have also performed detailed correlation length measurements i

Flavour degrees of freedom and the transition temperature in QCD

We study the finite temperature transition in QCD with four flavours of dynamical quarks. Our simulation is performed on an 8×16 3 lattice for quarks of mass ma=0.01. At the coupling β c =5.15, we find long-lived metastable states, as well as an abrupt change in the entropy density, suggesting a first order phase transition. Using presently available results from corresponding calculations of the

Lattice QCD with small number of flavours

The finite temperature behaviour of lattice QCD with dynamical quarks for small number of flavours Nf is investigated. Simulations have been performed on lattices of size N3σ·4 with Nσ=8 and 12 and staggered fermions of mass ma=0.1 using a hybrid algorithm. We find that the two state signal at the critical point of the pure gauge theory, which is taken as sign for a fiorst order phase transition,

Intracoronary Injection of Contrast Media Maps the Territory of the Coronary Artery. An MRI Technique for Assessing the Effects of Locally Delivered Angiogenic Therapies

Rationale and Objectives: The effects of locally delivered angiogenic factors or stem cells on the coronary artery perfusion territory are not well defined. Therefore, the aim of this study was to determine the ability of the selective injection of magnetic resonance contrast media (MR-CM) to map and quantify the territories of the major coronary arteries. Materials and Methods: Selective coronary

The finite temperature phase transition in four flavour QCD on an 8×12 3 lattice

We present results of a numerical study of lattice QCD with four dynamical flavours of staggered fermions, performed by using a hybrid Monte Carlo algorithm on an 8×12 3 lattice. We find a rapid change in the average value of the Polyakov loop at β c =5.25±0.025 for a quark mass ma=0.025; at this mass value, the behaviour of the chiral order parameter, 〈ΨΨ〉 does not yet allow an independent deter

A random surface representation of Wilson loops in Z(2) gauge theory

We study a random surface representation of Wilson loops in Z(2) gauge theory. The weights consist of an area factor, which dominates at strong coupling, and an excluded volume factor flavouring crumpled surfaces. We examine the latter one in some detail in three as well as four dimensions by use of Monte Carlo methods. In three dimensions, the critical behaviour of the surfaces is found to be det

The effective string and SU(2) lattice MC data

We present high statistics MC calculations of the static potential in three-dimensional SU(2) for a wide range of β values on a 243 lattice. The deviations from area law are unambiguously demonstrated by use of 2nd lattice R derivative. After a clear crossover at β=4.5 the data show signs of an effective string roughening up to β=6.5, while scaling is not strictly obeyed in this interval. Pure fer

Compact three-dimensional U(1) gauge theory reexamined

Convincing evidence of a nonvanishing string tension in the continuum limit of compact three-dimensional U(1) gauge theory is presented. It is based on Monte Carlo measurements of Wilson loops on a 323 lattice at =2.0 and 2.2. The observed string tensions at these couplings are consistent with the Polyakov theory. Also, a very clean signal of a string vibrational contribution to the potential is o

Myocardial microinfarction aF Ter coronary microembolization in swine : MR imaging characterization

Purpose: To use first-pass perfusion and delayed-enhanced (DE) magnetic resonance (MR) imaging for the detection of the early effects of coronary microembolization on myocardial perfusion and viability. Materials and Methods: Approval was obtained from the institutional committee on animal research. A hybrid x-ray and MR imaging system was used to guide the endovascular catheter and quantify the l

Measurement of Tc in the scaling region of (2+1)-dimensional SU(2) lattice gauge theory

The deconfinement temperature Tc of (2+1)-dimensional SU(2) gauge theory is measured on lattice sizes varying from 2 × 202 to 6 × 602 and with β in the rate 3-9. Approximative scaling is found for β > 6.5 and Tc/√σ = 0.94 ± 0.03 is obtained. This value is in excellent agreement with (3/π) 1 2, as predicted from the breakdown of SU(2) confinement in terms of an effective scalar string theory.

Numerical evidence for a mass gap in three-dimensional SU(2)

Numerical evidence for a nonvanishing 0++ glueball mass in three-dimensional SU(2) is presented. By using a long-distance correlation Monte Carlo method we obtain m0++ = (4.7±1.2)√σ in the β-range 4.0-6.5. The measurements are consistent with 1/β-scaling. The relevance of this result for SU(2) in four dimensions at finite temperature is briefly discussed.

Experimental and Numerical Investigations of Heat Transfer related to Gas Turbine Applications

Gas turbines are broadly used in aerospace and marine propulsion and power production etc.Investigation of heat transfer in gas turbines is a long-lasting and still an active subject ofresearch due to its tremendous importance. Thermal efficiency, durability and fatigue lifetimeof a gas turbine greatly rely on the heat transfer characteristics of gas turbine components.According to the first law o

Assessing cereal grain quality with a fully automated instrument using artificial neural network processing of digitized color video images

A fully integrated instrument for cereal grain quality assessment is presented. Color video images of grains fed onto a belt are digitized. These images are then segmented into kernel entities, which are subject to the analysis. The number of degrees of freedom for each such object is decreased to a suitable level for Artificial Neural Network (ANN) processing. Feed- forward ANN's with one hidden

Delta 2.0 - A program for finding dependencies in tables of data

A package written in C for identifying variable dependencies in tables of data is presented. The key ingredient is the δ-test, which establishes dependency structures by exploiting the properties of continuous functions using conditional probabilities formed out of the data. The method estimates most relevant variables, embedding dimensions and noise levels. The program, which is self-contained, a

Solving optimization problems with mean field methods

A brief review is given for the use of feed-back artificial neural networks (ANN) to obtain good approximate solutions to combinatorial optimization problems. The key element is the mean field approximation (MFT), which differs from conventional methods and "feels" its ways towards good solutions rather than fully or partly exploring different possible solutions. The methodology, which is illustra