PURPOSE To assess the validity of an MR method of evaluating tissue iron. METHODS The difference between the transverse relaxation rate (R2) measured with a high-field MR instrument and the R2 measured with a lower field instrument defines a measure termed the field-dependent R2 increase (FDRI). Previous in vivo and in vitro studies indicated that FDRI is a specific measure of tissue iron sto...

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...

The S = 1/2 Heisenberg antiferromagnet in the ladder geometry is studied as a model for the spin degrees of freedom of SrCu2O3. The susceptibility and the spin echo decay rate are calculated using a quantum Monte Carlo technique, and the spin-lattice relaxation rate is obtained by maximum entropy analytic continuation of imaginary time correlation functions. All calculated quantities are in rea...

We present a detailed theoretical analysis of the noble-gas nuclear spin relaxation due to the anisotropic magnetic-dipole hyperfine interaction between the noble-gas nucleus and alkali-metal valence electron vis à vis the already well-understood (spin-conserving) isotropic magnetic-dipole hyperfine interaction in alkali-metal–noble-gas systems. We find that, for all pairs in which the noblegas...

First measurements of proton relaxation on chloroplast membranes are presented here. Experiments show that the water proton spin-lattice relaxation rate in chloroplast thylakoid membrane suspensions can be used to monitor membrane-bound manganese. The relaxation effect is reduced to 0.4 of its original value upon manganese extraction by washing with either alkaline Tris buffer or NH2OH/EDTA sol...

I will talk about spin-orbit coupling (SOC) in π-conjugated organicmaterials and its effects on spin characteristics including the spin-relaxation time, spin-diffusion length, and g factor [1]. While π electrons are responsible for low-energy electrical and optical processes in π-conjugated organic solids, σ electrons must be explicitly included to properly describe the SOC. The SOC mixes upand...

Magnetic-based biosensors are attractive for on-site detection of biomarkers due to the low magnetic susceptibility of biological samples. Here, we report a highly sensitive magnetic-based biosensing system that is composed of a miniaturized nuclear magnetic resonance (NMR) device and magnetically engineered nanoferrite particles (NFPs). The sensing performance, also identified as the transvers...

2014 We consider the influence of antiferromagnetic nuclear ordering on the spin-lattice relaxation of the nuclear dipolar energy by paramagnetic impurities. The predictions are different depending whether the correlation time 03C4c of the spin-lattice coupling is shorter or longer than T2. When 03C4c ~ T2, relaxation is slower in the antiferromagnetic than in the paramagnetic state. When 03C4c...