Deuterium brain imaging at 7T during D O dosing.

Purpose: To characterize the ( H) deuterium MR signal measured from human brain at 7T in participants loading with D O to ˜1.5% enrichment over a six-week period.

Methods: H spectroscopy and imaging measurements were used to track the time-course of H enrichment within the brain during the initial eight-hour loading period in two participants.

Determining T2 relaxation time and stroke onset relationship in ischaemic stroke within apparent diffusion coefficient-defined lesions. A user-independent method for quantifying the impact of stroke in the human brain.

Background And Objective: In hyperacute ischaemic stroke, T2 of cerebral water increases with time. Quantifying this change may be informative of the extent of tissue damage and onset time. Our objective was to develop a user-unbiased method to measure the effect of cerebral ischaemia on T2 to study stroke onset time-dependency in human acute stroke lesions.

The effect of collagen fibril orientation on the biphasic mechanics of articular cartilage.

The highly inhomogeneous distribution of collagen fibrils may have important effects on the biphasic mechanics of articular cartilage. However, the effect of the inhomogeneity of collagen fibrils has mainly been investigated using simplified three-layered models, which may have underestimated the effect of collagen fibrils by neglecting their realistic orientation. The aim of this study was to investigate the effect of the realistic orientation of collagen fibrils on the biphasic mechanics of articular cartilage.

A nuclear magnetic resonance study of water in aggrecan solutions.

Aggrecan, a highly charged macromolecule found in articular cartilage, was investigated in aqueous salt solutions with proton nuclear magnetic resonance. The longitudinal and transverse relaxation rates were determined at two different field strengths, 9.4 T and 0.

Orthogonal invariant sets of the diffusion tensor and the development of a curvilinear set suitable for low-anisotropy tissues.

We develop a curvilinear invariant set of the diffusion tensor which may be applied to Diffusion Tensor Imaging measurements on tissues and porous media. This new set is an alternative to the more common invariants such as fractional anisotropy and the diffusion mode. The alternative invariant set possesses a different structure to the other known invariant sets; the second and third members of the curvilinear set measure the degree of orthotropy and oblateness/prolateness, respectively.

Macroscopic and microscopic study of 1-ethyl-3-methyl-imidazolium acetate-water mixtures.

Mixtures of 1-ethyl-3-methyl-imidazolium acetate ([C2mim][OAc]) and water across the entire composition range, from pure [C2mim][OAc] to pure water, have been investigated using density, viscosity, and NMR spectroscopy, relaxometry, and diffusion measurements. These results have been compared to ideal mixing laws for the microscopic data obtained from the NMR results and macroscopic data through the viscosity and density. It was also found that the mixing of the two fluids is exothermal.

Influence of cellulose on ion diffusivity in 1-ethyl-3-methyl-imidazolium acetate cellulose solutions.

Solutions of microcrystalline cellulose in 1-ethyl-3-methyl-imidazolium acetate have been investigated using pulsed-field gradient (1)H NMR. In all cases the geometrically larger cation was found to diffuse faster than the smaller anion. Arrhenius temperature analysis has been applied to the ion diffusivities giving activation energies.