Previous work has shown that undissociated forms of organic acids, such as formic, acetic, and propionic acids, increase the permeability of barley roots to ions. The work here was undertaken to test whether these undissociated acids affect the lipids from the root membranes in such a way as to account for the permeability increase. Relative amounts of the principal fatty acids from barley root...

We apply an accurate numerical scheme to solve for Stokes flow directly on binarized three-dimensional rock images, such as those obtained by micro-CT imaging. The method imposes no-flow conditions exactly at the solid boundaries and employs an algebraic multigrid method to solve for the resultant set of linear equations. We compute the permeability of a range of consolidated and unconsolidated...

Refuse degradation and landfill leachate treatment are the main research directions of landfill technology at present, but permeability characteristics of landfill body are paid little attention on. According to this actuality, the study selected four kinds of landfill's bodies under different pressures as study objects and tested the permeability characteristics in the stage of main compressio...

Three commonly used methods to determine the principal moments of inertia of a plane area and their directions are based on: (i) the stationarity condition for the axial moment of inertia, (ii) the eigenvalue analysis, and (iii) Mohr’s circle. In this paper we provide two new derivations, which are based on: (a) the matrix diagonalization and the invariant tensor properties, and (b) the conjuga...

Hillslope scale runoff is generated as a result of interacting factors that include water influx rate, surface and subsurface properties, and antecedent saturation. Heterogeneity of these factors affects the existence and characteristics of runoff. This heterogeneity becomes an increasingly relevant consideration as hydrologic models are extended and employed to capture greater detail in runoff...

Biliary excretion (BE) is a major elimination pathway, and its prediction is particularly important for optimization of systemic and/or target-site exposure of new molecular entities. The objective is to characterize the physicochemical space associated with hepatobiliary transport and rat BE and to develop in silico models. BE of 123 in-house compounds was obtained using the bile-duct cannulat...

on the permeability of protoplasmic membranes to water. Our experimental tissue was the hypocotyl of Helianthus annuus. We have observed the effect of such factors on the permeability of the cells toward water passing both in the inward and in the outward directions. The rate of entry of water into uniform segments of tissue is a function of A, the difference in diffusion pressure deficit (DPD)...

Human aquaporin 4 has been studied using molecular dynamics (MD) simulations in the absence and presence of pulses of external static electric fields. The pulses were 10 ns in duration and 0.012-0.065 V/Å in intensity acting along both directions perpendicular to the pores. Water permeability and the dipolar response of all residues of interest (including the selectivity filter) within the pore...

The concept of a differential Shack-Hartmann (DSH) curvature sensor was recently proposed, which yields wavefront curvatures by measuring wavefront slope differentials. As an important feature of the DSH curvature sensor, the wavefront twist curvature terms can be efficiently obtained from slope differential measurements, thus providing a means to measure the Monge-equivalent patch. Specificall...

When performing subspace modelling of data using Principal Component Analysis (PCA) it may be desirable to constrain certain directions to be more meaningful in the context of the problem being investigated. This need arises due to the data often being approximately isotropic along the lesser principal components, making the choice of directions for these components more-or-less arbitrary. Furt...