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Imaging of cardiac perfusion with MR is a challenging area of research especially due to the motion of the heart and limited time of data acquisition. Compressed sensing is a popular signal estimation method recently adopted by researchers in MRI which can improve the spatial and/or temporal resolution of the acquired images by reducing the number of necessary samples for image reconstruction. This paper focuses on performance of temporal regularization with total variation and wavelets in compressed sensing. The impact of the choice of regularization parameters on the image quality and the temporal variation of intensity in region of interests (ROIs) are discussed. It is found that selecting the regularization parameter so as to optimize the quality of the reconstructed image sequence as a whole, leads to erroneous reconstruction of certain regions due to over regularization.

Magnetization reversal and magnetoresistance behavior of perpendicularly magnetized [Co/Pd]4/Au/[Co/Pd]2 nanowires J. Appl. Phys. 112, 073902 (2012) Electric-field control of CoFeB/IrMn exchange bias system J. Appl. Phys. 112, 064120 (2012) Critical effect of spin-dependent transport in a tunnel barrier on enhanced Hanle-type signals observed in threeterminal geometry Appl. Phys. Lett. 101, 132411 (2012) Giant tunneling magnetoresistance in epitaxial Co2MnSi/MgO/Co2MnSi magnetic tunnel junctions by halfmetallicity of Co2MnSi and coherent tunneling Appl. Phys. Lett. 101, 132418 (2012) Interface mediated ferromagnetism in bulk CuO/Cu2O composites Appl.Theoretical calculations and models to explain two unusual features of Fe/Cr magnetically layered structures are presented: (I) Strong antiferromagnetic (AF) couplings between Fe layers separated by Cr layers have been found in Fe/Cr/Fe sandwiches and Fe/Cr superlattices. These AF couplings are too strong to be accounted for by dipolar interactions and have to be ascribed to exchange interactions through the Cr layers. The interlayer exchange coupling from numerical calculations of the electronic structure of Fe/Cr superlattices based on the local density approximation is derived. (2) Recently, giant magnetoresistance effects have been found in Fe/Cr magnetically layered structures for currents in the plane of the layers. The spin-dependent scattering at the Fe/Cr interfaces that comes from interface roughness, as well as that in the bulk of the layers are considered. The resistivity of these magnetic superlattices are calculated by adapting the quantum treatment of the electrical conductivity of ultrathin metallic films. We find the resistivity when the Fe moments in adjacent layers are parallel and anti parallel, and compare the results with experimental data.

1994 organic chemistry, review organic chemistry, review Z 0200 09 -320 Synthetic DNA Knots and Catenanes -(79 refs.). -(SEEMAN, N. C.; CHEN, J.; DU, S. M.; MUELLER, J. E.; ZHANG, Y.; FU, T.-J.; WANG, Y.; WANG, H.; ZHANG, S.; New J.