Several problems in the physics of L→H transition and pedestal formation are examined using a simple and universal sandpile model, which incorporates key features of a confined plasma, namely, diffusion, shear induced bistability of turbulent transport, and a local magnetohydrodynamic !MHD" limit on the gradient. The main focus of this study is the effect of ambient diffusion, representative of...

We analyze the unforced and deterministically forced Burgers equation in the framework of the (diffusive) interpolating dynamics that solves the so-called Schrödinger boundary data problem for the random matter transport. This entails an exploration of the consistency conditions that allow to interpret dispersion of passive contaminants in the Burgers flow as a Markovian diffusion process. In g...

The technique of DGT (diffusive gradients in thin films) was applied to obtain high-resolution vertical profiles of dissolved reactive phosphorus (DRP) in sediment porewater of Lake Chaohu, a shallow eutrophication lake. Three kinds of DGT probes (with three thicknesses of diffusive gel: 0.38 mm, 0.78 mm and 1.18 mm) measured vertical concentration and induced flux from solid to solution phase ...

Microtubules (MTs) nucleated by centrosomes form star-shaped structures referred to as asters. Aster motility and dynamics is vital for genome stability, cell division, polarization and differentiation. Asters move either toward the cell center or away from it. Here, we focus on the centering mechanism in a membrane independent system of Xenopus cytoplasmic egg extracts. Using live microscopy a...

Sodium mass balance is primarily dependent on two factors: dietary salt intake and sodium removal during haemodialysis (HD). Salt intake during the interdialysis period is dependent on patient behaviour and is a strong driver of volume overload [1]. The average American consumes ∼149 mmol/day [2]; most Western societies consume between 150 and 250 mmol/day [3]. There is evidence that HD patient...

The diffusive streaming of 1.3to 2.3-MeV per nucleon protons has been found to be predominantly toward the sun during periods between prompt solar particle events. This sunward streaming occurs for essentially all proton intensities from <0.012 to 1.2 (cm •' s sr MeV) -• and for all solar wind velocities. The average radial component (16% + 3%) of the diffusive anisotropy of 1.4to 2.4-MeV per n...

As a counterpoint to classical stochastic particle methods for diffusion, we develop a deterministic particle method for linear and nonlinear diffusion. At first glance, deterministic particle methods are incompatible with diffusive partial differential equations since initial data given by sums of Dirac masses would be smoothed instantaneously: particles do not remain particles. Inspired by cl...