All Outputs (21)

Deuterium brain imaging at 7T during D2O dosing (2022)
Journal Article

Purpose To characterize the (2H) deuterium MR signal measured from human brain at 7T in participants loading with D2O to ˜1.5% enrichment over a six-week period. Methods 2H spectroscopy and imaging measurements were used to track the time-course... Read More about Deuterium brain imaging at 7T during D2O dosing.

A Comparison of T2 Relaxation-Based MRI Stroke Timing Methods in Hyperacute Ischemic Stroke Patients: A Pilot Study (2020)
Journal Article

Background: T2 relaxation-based magnetic resonance imaging (MRI) signals may provide onset time for acute ischemic strokes with an unknown onset. The ability of visual and quantitative MRI-based methods in a cohort of hyperacute ischemic stroke patie... Read More about A Comparison of T2 Relaxation-Based MRI Stroke Timing Methods in Hyperacute Ischemic Stroke Patients: A Pilot Study.

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 (2019)
Journal Article

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 measu... Read More about 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.

Quantifying T2 relaxation time changes within lesions defined by apparent diffusion coefficient in grey and white matter in acute stroke patients (2019)
Journal Article

The apparent diffusion coefficient (ADC) of cerebral water, as measured by diffusion MRI, rapidly decreases in ischaemia, highlighting a lesion in acute stroke patients. The MRI T2 relaxation time changes in ischaemic brain such that T2 in ADC lesion... Read More about Quantifying T2 relaxation time changes within lesions defined by apparent diffusion coefficient in grey and white matter in acute stroke patients.

Observation of angular dependence of T1 in the human white matter at 3T (2019)
Journal Article

Background and Objective: Multiple factors including chemical composition and microstructure influence relaxivity of tissue water in vivo. We have quantified T1 in the human white mater (WM) together with diffusion tensor imaging to study a possible... Read More about Observation of angular dependence of T1 in the human white matter at 3T.

Imaging of nuclear magnetic resonance spin-lattice relaxation activation energy in cartilage (2018)
Journal Article

Samples of human and bovine cartilage have been examined using magnetic resonance imaging to determine the proton nuclearmagnetic resonance spin-lattice relaxation time, T1, as a function of depth within the cartilage tissue. T1 was measured at five... Read More about Imaging of nuclear magnetic resonance spin-lattice relaxation activation energy in cartilage.

Grassmann variables and pseudoclassical Nuclear Magnetic Resonance (2016)
Journal Article

The concept of a propagator is useful and is a well-known object in diffusion NMR experiments. Here, we investigate the related concept; the propagator for the magnetization or the Green's function of the Torrey-Bloch equations. The magnetization pro... Read More about Grassmann variables and pseudoclassical Nuclear Magnetic Resonance.

The effect of collagen fibril orientation on the biphasic mechanics of articular cartilage (2016)
Journal Article

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-la... Read More about The effect of collagen fibril orientation on the biphasic mechanics of articular cartilage.

A nuclear magnetic resonance study of water in aggrecan solutions (2016)
Journal Article

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 strength... Read More about A nuclear magnetic resonance study of water in aggrecan solutions.

A nondestructive method to distinguish the internal constituent architecture of the intervertebral discs using 9.4 tesla magnetic resonance imaging (2015)
Journal Article

Study Design. An in vitro study of the intervertebral disc (IVD) structure using 9.4T magnetic resonance imaging (MRI). Objective. Investigate the potential of ultrahigh-field strength MRI for higher quality 3-dimensional (3D) volumetric MRI datasets... Read More about A nondestructive method to distinguish the internal constituent architecture of the intervertebral discs using 9.4 tesla magnetic resonance imaging.

Orthogonal invariant sets of the diffusion tensor and the development of a curvilinear set suitable for low-anisotropy tissues (2013)
Journal Article

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

Macroscopic and microscopic study of 1-Ethyl-3-methyl-imidazolium acetate-water mixtures (2012)
Journal Article

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 mea... Read More about Macroscopic and microscopic study of 1-Ethyl-3-methyl-imidazolium acetate-water mixtures.

Spin-lattice relaxation rates and water content of freeze-dried articular cartilage (2012)
Journal Article

Objective: Nuclear magnetic resonance (NMR) spin-lattice relaxation rates were measured in bovine and porcine articular cartilage as a function of water content. Methods: Water content was varied by freeze-drying samples for short periods of time (up... Read More about Spin-lattice relaxation rates and water content of freeze-dried articular cartilage.

Influence of cellulose on ion diffusivity in 1-ethyl-3-methyl-imidazolium acetate cellulose solutions (2010)
Journal Article

Solutions of microcrystalline cellulose in 1-ethyl-3-methyl-imidazolium acetate have been investigated using pulsedfield gradient 1H NMR. In all cases the geometrically larger cation was found to diffuse faster than the smaller anion. Arrhenius tempe... Read More about Influence of cellulose on ion diffusivity in 1-ethyl-3-methyl-imidazolium acetate cellulose solutions.

Two-dimensional NMR of velocity exchange: VEXSY and SERPENT (2001)
Journal Article

Two different multidimensional pulsed field gradient sequences are compared which have the purpose of correlating spin displacements in different time intervals with each other. The simplest possible sequence, three-pulse SERPENT, measures displaceme... Read More about Two-dimensional NMR of velocity exchange: VEXSY and SERPENT.

Pore-scale network modelling of flow propagators derived from pulsed magnetic field gradient spin echo NMR measurements in porous media (2000)
Journal Article

Pulsed magnetic field gradient spin echo (PGSE) NMR experiments carried out on porous media where fluid flow is occurring, may be analyzed to give the propagator, P(ξ,t), This quantity is the ensemble density distribution of particle (nuclei) displac... Read More about Pore-scale network modelling of flow propagators derived from pulsed magnetic field gradient spin echo NMR measurements in porous media.

Time Correlations in Fluid Transport Obtained by Sequential Rephasing Gradient Pulses (1999)
Journal Article

We present a basic experiment by which the evolution of the displacement probability density (propagator) of static or flowing fluid in N successive time intervals is obtained by single labeling, coupled with multiple rephasing events during the cour... Read More about Time Correlations in Fluid Transport Obtained by Sequential Rephasing Gradient Pulses.

The characterisation of fluid transport in porous solids by means of pulsed magnetic field gradient NMR (1998)
Journal Article

The determination, by pulsed field gradient (PFG) nuclear magnetic resonance (NMR), of the probability distributions (propagators) of displacements for fluids undergoing transport by both flow and self- diffusion within porous solids is outlined. The... Read More about The characterisation of fluid transport in porous solids by means of pulsed magnetic field gradient NMR.

Predictions for pulsed-field-gradient NMR experiments of diffusion in fractal spaces (1997)
Journal Article

In this paper, theoretical predictions are made for pulsed-field-gradient NMR experiments of diffusion in fractal spaces. We obtain the general q-space behaviour of the NMR signal, which upon Fourier transformation, delivers the probability density f... Read More about Predictions for pulsed-field-gradient NMR experiments of diffusion in fractal spaces.

Magnetic resonance imaging of peripheral vascular disease and muscle atrophy in diabetes (1994)
Journal Article

Knowledge of the state of tissue hydration in patients suffering from peripheral vascular disease and neuropathy as a result of diabetes is important in their treatment. Further, because magnetic resonance imaging (MRI) is uniquely able to generate i... Read More about Magnetic resonance imaging of peripheral vascular disease and muscle atrophy in diabetes.