Projection of a quantum state on eigenstates of average Hamiltonian

Magnetization transfer in a partly deuterated lyotropic liquid crystal by single- and dual-frequency RF irradiations

The mechanism of magnetization transfer (MT) in a lyotropic liquid crystal made of sodium dodecyl sulfate, decanol, and water molecules is investigated by using deuterated molecules and single- and dual-frequency RF irradiations. The resulting Z-spectra suggest that the decanol molecules are mainly responsible for the MT effects in this system, through proton exchange to water. This is further confirmed by monitoring the relaxation of dipolar order, which allows one to estimate the transfer rate of magnetization from decanol to water. The potential benefits of using dual-frequency RF irradiation for inducing MT effects are explored through numerical solutions to a MT model based on Provotorov's partial saturation theory.

Regional right ventricular wall motion in tetralogy of fallot: a three dimensional analysis

We observed an abnormal contraction pattern in the right ventricle (RV) in postoperative tetralogy of Fallot (TOF) patients when measuring the regional contribution to global stroke volume (rSV) of 20 RV slices from apex to base. We compared the rSV method's performance with the centersurface method which offers greater flexibility in defining regions of interest. We reconstructed the RV in 3D from manually traced borders in 20 repaired TOF patients and nine normal subjects from cardiac magnetic resonance images. Wall motion was measured as the local orthogonal distance between the RV endocardium at end diastole and end systole. The RV was divided into septum, conus, and 10 free wall regions. For comparison with the rSV method the free wall regions were grouped into apical, mid, and basal levels. The RV was also divided into two other 3-part models for comparison. Both rSV and centersurface methods showed that TOF patients have diminished function at the base and increased function at the apex compared to normal. The other 3-part models were less informative because large region size obscured local function abnormalities. Septal and free wall motion differed between the groups. Two analysis methods agreed that patients with TOF have a pattern of relatively increased wall motion at the apex and diminished function at the base compared to normal. The centersurface analysis showed that characterization of the RV's complex pattern of regional function requires more than three RV subdivisions.

Numerical simulation of NQR/NMR: Applications in quantum computing

A numerical simulation program able to simulate nuclear quadrupole resonance (NQR) as well as nuclear magnetic resonance (NMR) experiments is presented, written using the Mathematica package, aiming especially applications in quantum computing. The program makes use of the interaction picture to compute the effect of the relevant nuclear spin interactions, without any assumption about the relative size of each interaction. This makes the program flexible and versatile, being useful in a wide range of experimental situations, going from NQR (at zero or under small applied magnetic field) to high-field NMR experiments. Some conditions specifically required for quantum computing applications are implemented in the program, such as the possibility of use of elliptically polarized radiofrequency and the inclusion of first- and second-order terms in the average Hamiltonian expansion. A number of examples dealing with simple NQR and quadrupole-perturbed NMR experiments are presented, along with the proposal of experiments to create quantum pseudopure states and logic gates using NQR. The program and the various application examples are freely available through the link http://www.profanderson.net/files/nmr_nqr.php.