Introduction Recent studies have shown that T2 relaxation may be anisotropic [1-4]. This anisotropy has been attributed to the microscopic (sub-voxel level) anisotropic distribution of susceptibility perturbers. In white matter fiber bundles, these anisotropic pertubations could originate from compounds such as lipid and ferritin that may align with axons, and could generate magnetic field vari...

A dynamic Cournot duopoly game, whose time evolution is modeled by the iteration of a map T : …x; y† ! …r1…y†; r2…x††, is considered. Results on the existence of cycles and more complex attractors are given, based on the study of the one-dimensional map F …x† ˆ …r1 r2†…x†. The property of multistability, i.e. the existence of many coexisting attractors (that may be cycles or cyclic chaotic sets...

UNLABELLED Attenuation correction (AC) is a critical requirement for quantitative PET reconstruction. Accounting for bone information in the attenuation map (μ map) is of paramount importance for accurate brain PET quantification. However, to measure the signal from bone structures represents a challenging task in MR. Recent (18)F-FDG PET/MR studies showed quantitative bias for the assessment o...

OBJECTIVE To explore the transverse relaxation rate with gradient echo R2(*) changes in patients with Parkinsonian variant of multiple system atrophy (MSA-P) with a voxel-based analysis of R2(*) map. METHODS Whole brain structural images and multi-echo T2(*) weighted image were acquired in 27 patients with probable MSA-P and 24 healthy individuals. R2(*) maps of the MSA-P were compared with t...

PURPOSE To introduce macroscopic B0 field inhomogeneity-compensated volumetric R2 * mapping method with a three-dimensional (3D) z-shim multi-echo acquisition. METHODS The proposed z-shim sequence acquired conventional and z-shimmed echoes alternately with bipolar readout gradients. A constant-valued z-shim gradient was applied prior to each negative readout gradient lobe. A phase combination...

The respective contribution of systemic vascular resistance (R) and total arterial compliance (C) to the arterial load remains to be established in humans. Effective arterial elastance (Ea), i.e., the left ventricular end-systolic pressure (LVESP)-over-stroke volume ratio, is a reliable estimate of arterial load. It is widely accepted that Ea mainly relates to mean aortic pressure (MAP) and thu...

OBJECTIVES/HYPOTHESIS The aim of this study was to discover the optimal effect-site concentration of remifentanil for cough prevention that does not delay awakening or cause respiratory depression during emergence from anesthesia with propofol and remifentanil in laryngomicrosurgery patients. STUDY DESIGN Prospective, randomized, controlled trial. METHODS One hundred five patients were rand...

Let F= (f, g) : R2 → R2 be a polynomial map such that det DF(x) is different from zero for all x ∈ R2. We assume that the degrees of f and g are equal. We denote by f and G the homogeneous part of higher degree of f and g, respectively. In this note we provide a proof relied on qualitative theory of differential equations of the following result: If f and g do not have real linear factors in co...