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Agreement of left ventricular mass in steady state free precession and delayed enhancement MR images : Implications for quantification of fibrosis in congenital and ischemic heart disease

Background: Left ventricular mass (LVM) is used when expressing infarct or fibrosis as a percentage of the left ventricle (LV). Quantification of LVM is interchangeably carried out in cine steady state free precession (SSFP) and delayed enhancement (DE) magnetic resonance imaging (MRI). However, these techniques may yield different LVM. Therefore, the aim of the study was to compare LVM determined

Color structure for soft gluon resummation: A General recipe

A strategy for calculating the color structure needed for soft gluon resummation for processes with any number of colored partons is introduced using a Nc → ∞inspired basis. In this basis a general formalism can be found at the same time as the calculations are simplified.The advantages are illustrated by recalculating the soft anomalous dimension matrix for the processes gg → gg, qq → qqg and qq

The theory of dynamical random surfaces with extrinsic curvature

We analyse numerically the critical properties of a two-dimensional discretized random surface with extrinsic curvature embedded in a three-dimensional space. The use of the toroidal topology enables us to enforce the non-zero external extension without the necessity of defining a boundary and allows us to measure directly the string tension. We show that a phase transition from the crumpled phase

Multiple interactions, diffraction, and the BFKL pomeron

In high energy pp scattering the inclusive cross section for minijet production is very large. Unitarity then implies a high probability for multiple interactions, and a large diffractive cross section. As the proton has a substructure in terms of parton cascades, the diffraction is not only elastic, but has a large component of diffractive excitation. The cascades can fill the whole rapidity ran

Negative predictive value and potential cost savings of acute nuclear myocardial perfusion imaging in low risk patients with suspected acute coronary syndrome : A prospective single blinded study

Background: Previous studies from the USA have shown that acute nuclear myocardial perfusion imaging (MPI) in low risk emergency department (ED) patients with suspected acute coronary syndrome (ACS) can be of clinical value. The aim of this study was to evaluate the utility and hospital economics of acute MPI in Swedish ED patients with suspected ACS. Methods: We included 40 patients (mean age 55

Spiral wound modules for high viscosity solutions at high temperature: Carrageenan concentration with ultrafiltration

Spiral wound modules are the most common modules in the industry due to their low investment and replacement costs plus high packing density. The use of spiral wound modules is often restricted to feed streams with a low temperature (< 75°C) and a low viscosity. The focus of this paper is on a new generation of spiral wound modules, which has been introduced by Alfa Laval Membrane Technology for t

Disappearance of myocardial perfusion defects on prone SPECT imaging : Comparison with cardiac magnetic resonance imaging in patients without established coronary artery disease

Background: It is of great clinical importance to exclude myocardial infarction in patients with suspected coronary artery disease who do not have stress-induced ischemia. The diagnostic use of myocardial perfusion single-photon emission computed tomography (SPECT) in this situation is sometimes complicated by attenuation artifacts that mimic myocardial infarction. Imaging in the prone position ha

Scaling properties at the crumpling transition

We investigate numerically a dynamically triangulated random surface with extrinsic curvature embedded in a three-dimensional space. Toroidal topology is used, to allow for string tension measurements by a new method. A high statistics test of the finite-size scaling of the specific heat is performed.

Assessing the Effects of Climate Change and Air Pollution on Soil Properties and Plant Diversity in Northeastern U.S. Hardwood Forests : Model Setup and Evaluation

The integrated forest ecosystem model ForSAFE-Veg was used to simulate soil processes and understory vegetation composition at three—sugar maple, beech, yellow birch—hardwood forest sites in the Northeastern United States (one at Hubbard Brook, NH, and two at Bear Brook, ME). Input data were pooled from a variety of sources and proved coherent and consistent. While the biogeochemical component For

Physics beyond instantons. Measuring the physical correlation length

In broken-symmetry phases of models with discrete global symmetry, the physical correlation length can be measured using time-slice correlators projected to non-zero momenta. A transfer matrix based argument is used to construct the finite-size scaling for this quantity. We extract the correlation length for the two-dimensional ten-state Potts model by this means, and the surface tension from the

Hadronic correlation functions in the QCD plasma phase

We present results for static hadronic correlation functions in the high temperature phase of QCD, obtained by the MTc collaboration. The measured screening lengths are compared with values for a gas of free quarks. In the ρ{variant} and N channels deviations from free quark propagation are found to be small at temperatures T ≥ 1.5Tc.

The heavy quark potential in SU(2) gauge theory at high temperature

We present a detailed investigation of the heavy quark potential in the deconfined phase of pure SU(2) gauge theory at intermediate temperatures. The analysis is based on close comparison of numerical and analytical methods. The extent of the short-distance range, where because of asymptotic freedom perturbation theory gives a good description of the interaction, is determined. Slightly beyond the

Spectral density analysis of the chiral transition in nf=4 finite temperature QCD

We apply the spectral density reweighting technique to the analysis of the chiral phase transition in finite-temperature lattice quantum chromodynamics (QCD) with four flavors of dynamical staggered fermions and mqa=0.025. Our simulations were performed using the hybrid Monte Carlo method for LtL3 lattices with Lt=4 and L=6, 8 and 10. We calculate partition function zeros, as well as the maxima of

Identification of residual ischemia, infarction, and microvascular impairment in revascularized myocardial infarction using 64-slice MDCT

This study aimed to assess the potential of 64-slice MDCT in characterizing revascularized infarcted myocardium at the cellular and microvascular levels. Pigs (n=7) underwent 2 h left anterior descending coronary artery occlusion/reperfusion. In acute (2-4 h) and subacute (1 week) infarction, first-pass perfusion (FPP) (1 ml/kg of 300 mg/ml Omnipaque) was performed using a cine (rotation time 60 s

Critical properties of the dynamical random surface with extrinsic curvature

We analyze numerically the critical properties of a two-dimensional discretized random surface with extrinsic curvature embedded in a three-dimensional space. The use of the toroidal topology enables us to enforce the non-zero external extension without the necessity of defining a boundary and allows us to measure directly the string tension. We show that a most probably second- order phase transi

Dynamics near a first-order phase transition with the Metropolis and Swendsen-Wang algorithms

We have simulated the 10-state 2d Potts model with the Metropolis and Swendsen-Wang algorithms, in order to compare their performances near a first-order phase transition. We show that a simple Markov model relates the frequencies of the flips between coexisting phases and the auto-correlation times. It leads to a coherent description of the dynamics. The ratio of the algorithm efficiencies has li