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...

Direct estimates of the radial diffusion coefficient • for 1.3-2.3 MeV protons in rr interplanetary space are made by comparing simultaneous observations of the diffusive anisotropy and radial gradient of these particles within recurrent streams. The 1.3-2.3 MeV proton anisotropy has been measured at 1 AU by the Caltech Electron/Isotope Spectrometers on IMP-7 and 8 during recurrent proton event...

We propose a theoretical prototype of a micro-scale turbine externally driven by diffusive heat flux without the need for macroscopic particle flux, which is in sharp contrast to conventional turbines. The prototypes are described analytically and validated by computer simulations. Our results indicate that a micro-scale turbine composed of anisotropic blades can rotate unidirectionally in an e...

This manuscript describes a new method to generate purely diffusive chemical gradients that can be modified in time. The device is simple in its design and easy to use, which makes it amenable to study biological processes that involve static or dynamic chemical gradients such as chemotaxis. We describe the theory underlying the convection-free gradient generator, illustrate the design to imple...

The law of conservation of linear momentum is applied to surface gas exchanges, employing scale analysis to diagnose the vertical velocity (w) in the boundary layer. Net upward momentum in the surface layer is forced by evaporation (E) and defines non-zero vertical motion, with a magnitude defined by the ratio of E to the air density, as w = E ρ . This is true even right down at the surface whe...

Low dialysate sodium concentrations have been associated with intradialytic symptoms such as muscle cramps and hypotensive episodes. High dialysate sodium concentrations lead to sodium loading, thirst and subsequent increase in interdialytic weight gain and hypertension. The optimal dialysate sodium concentration for an individual depends on the serum sodium concentration. The difference betwee...