This work deals with the short-time effective diffusion coefficient of charged and uncharged liposomes, measured ~as a function of the volume fraction! using fiber optic dynamic light scattering. Particularly, we are interested in the interplay between electrostatic and hydrodynamic interactions on the diffusion of these lipid vesicles. Regarding the charged liposome, it has been found that the...

Abstract. In this article we design the semi-implicit finite volume scheme for coherence enhancing diffusion in image processing and prove its convergence to the weak solution of the problem. The finite volume methods are natural tools for image processing applications since they use piecewise constant representation of approximate solutions similarly to the structure of digital images. They ha...

The partial volume effect is a significant limitation in medical imaging that results in blurring when the boundary between two structures of interest falls in the middle of a voxel. A new anisotropic diffusion method allows one to create interpolated 3D images corrected for partial volume, without enhancement of noise. After a zero-order interpolation, we apply a modified version of the anisot...

We investigate the Brownian motion of hard-sphere colloids near a solid wall by Evanescent Wave Dynamic Light Scattering (EWDLS). We carried out measurements for various volume fractions of sterically stabilized poly(methyl methacrylate) (PMMA) particles over a range of scattering wave vectors, q. While in the dilute regime, the near wall short-time diffusion is significantly slowed down due to...

Packed erythrocytes are ideally suited as a model system for the study of water diffusion in biological tissue, because cell size, membrane permeability, and extracellular volume fraction can be varied independently. We used a pulsed-field-gradient spin echo NMR technique to measure the time-dependent diffusion coefficient D(t) in packed erythrocytes. The long-time diffusion constant, D(eff), d...

PURPOSE COPD is a progressive disease, which can take different routes, leading to great heterogeneity. The aim of the post-hoc analysis reported here was to perform continuous analyses of advanced lung function measurements, using linear and nonlinear regressions. PATIENTS AND METHODS Fifty-one COPD patients with mild to very severe disease (Global Initiative for Chronic Obstructive Lung Dis...

Changes in brain extracellular space (ECS) volume, composition, and geometry are a consequence of neuronal activity, of glial K+, pH, and amino acid homeostasis, and of changes in glial cell morphology, proliferation, and function. They occur as a result of repetitive neuronal activity, seizures, anoxia, injury, inflammation, and many other pathological states in the CNS, and may significantly ...

PURPOSE To derive a mathematical model of TMA+ diffusion across the retina that can be used to estimate the amplitude and kinetics of the light-evoked increase in subretinal hydration and its effect on the concentration of other ions. METHODS All experimental data were obtained in chick retina-pigment epithelium-choroid preparations as described in the accompanying paper. RESULTS Diffusiona...

Changes in extracellular space (ECS) diffusion parameters in astrogliotic tissue around a unilateral cortical stab wound were determined from concentration-time profiles of tetramethylammonium (TMA(+)) using TMA(+)-selective microelectrodes. Three diffusion parameters-ECS volume fraction alpha (alpha = ECS volume/ total tissue volume), tortuosity lambda (lambda(2) = D/ADC; where D is the free a...