In the FIDA experiment, a pressure gradient generates the flow resulting in a parabolic flow profile. The parabolic flow profile inside the capillary distorts the indicator zone resulting in a concentration gradient between the center and the periphery of the capillary (figure S1). Equation 5 in the main manuscript is valid provided there is sufficient time for radial diffusion, and that advect...

Electrostatic plasma accelerators which avoid the space charge limitations of conventional ion rockets are described. Additional advantages for these devices include moderate requirements on magnetic field strength, and on power level. In cylindrical and annular geometries, neutral plasmas can exhibit axial acceleration under the influence of externally applied axial electrostatic fields in the...

background: carbon monoxide (co) poisoning may lead to hypoxic/anoxic injury and eventually ischemic encephalopathy. magnetic resonance imaging (mri) has a well-recognized role in assessment of the severity of brain damage caused by co poisoning. in this study, we aimed to present and analyze the structural abnormalities in the brain mri and especially in diffusion weighted mri (dwi) images in ...

Introduction: Single-shot echo-planar imaging (SS-EPI) has been widely used for diffusion imaging, primarily due to its rapid data acquisition speed, robustness against motion, and low specific absorption rate (SAR). SS-EPI, however, not only suffers from severe off-resonance effects such as magnetic susceptibility variations but also exhibits severe distortion in non-axial planes due to concom...

MR diffusion kurtosis imaging (DKI) was proposed recently to study the deviation of water diffusion from Gaussian distribution. Mean kurtosis, the directionally averaged kurtosis, has been shown to be useful in assessing pathophysiological changes, thus yielding another dimension of information to characterize water diffusion in biological tissues. In this study, orthogonal transformation of th...

Heart failure (HF) patients show brain tissue loss or injury in autonomic, cognitive, and emotional regulatory areas (1, 2); the regions with tissue injury overlap sites of altered functional MRI signals to autonomic challenges (3, 4). Some structural injury appears on T2-relaxometry procedures, and could result from different pathological processes, including hypoxia/ischemia accompanying perf...

OBJECTIVE To assess whether the pattern of diffusion changes among a cohort of individuals showing BMI-related increases in white matter volume reflects healthy expansion of myelin or damaged white matter. METHODS Diffusion MRI measures (axial, radial, and fractional anisotropy) were obtained from 94 females, aged 52-92. Relationships between BMI and diffusion measures were assessed controlli...

Molecular dynamics simulation was employed to investigate the diffusion behaviors of water molecules within a (5,5) carbon nanocoil (CNC) at different tensile strains, the length and coil diameter of CNC are 22 and 6.83 Ǻ, respectively. Condensed-phase, optimized molecular potentials for atomistic simulation studies were employed to model the interaction between atoms. The results show that the...

The effects of ambipolar diffusion on the linear stability of weakly ionised accretion discs are examined. Earlier work on this topic has focused on axial magnetic fields and perturbation wavenumbers. We consider here more general field and wavenumber geometries, and find that qualitatively new results are obtained. Provided a radial wavenumber and azimuthal field are present along with their a...

Received on: Mar 27, 2012 – Accepted on: Apr 23, 2012 A 65-year-old male patient with no past medical history, complains of sudden loss of memory that lasted about four hours. He was submitted to a magnetic resonance image (MRI) of the cranium, which showed no alterations. Follow-up MRI 48 hours later showed a diffusion restriction focus in the left hippocampus, consistent with the clinical hyp...