The major factors contributing to the selectivity of charged synthetic membranes are discussed. Transport through porous polyelectrolyte membranes, containing water-filled interstices, can be predicted approximately from Donnan equilibria, representing the interaction between polyelectrolyte and counter-ions by "ion-binding". A simple relation between permselectivity and maximal salt rejection ...

2010 marked the 50th anniversary of the use of selectivity triangles to characterize chromatographic phases. Such plots ultimately identify and quantify the blend of intermolecular interactions that occur between solutes and solvents/phases. The first chromatographic triangle was proposed by Brown and applied to GC stationary phases. Snyder then developed the influential solvent selectivity tri...

Discriminating ability (selectivity) of chemoreceptor neuron is compared with that of its receptor proteins. The process of neuronal triggering is expected to be cooperative and threshold-type in a sense that the neuron can fire if and only if the number of its receptor proteins, which are bound with odor molecules, is above a definite threshold. Both deterministic and stochastic pictures are c...

The purpose of the Perspectives in General Physiology is to provide a forum where scientific uncertainties or controversies are discussed in an authoritative, yet open manner. The Perspectives are solicited by the editors— often based on recommendations by members of the editorial advisory board. To frame the issue, two or more experts are invited to present brief points of view on the problem;...

Object recognition requires both selectivity among different objects and tolerance to vastly different retinal images of the same object, resulting from natural variation in (e.g.) position, size, illumination, and clutter. Thus, discovering neuronal responses that have object selectivity and tolerance to identity-preserving transformations is fundamental to understanding object recognition. Al...

Orientation selectivity is an important emergent property of neurons in the primary visual cortex, and inhibition is thought to play an important role in establishing this selectivity. But the relationship between strength of inhibition and orientation selectivity is unclear. To investigate this relationship, we electrophoretically applied the inhibitory transmitter GABA and the GABA(A) antagon...

This study focused on the response properties underlying selectivity for the rate of frequency modulated (FM) sweeps in the auditory cortex of anesthetized C57bl/6 (C57) mice. Linear downward FM sweeps with rates between 0.08 and 20 kHz/ms were tested. We show that at least two different response properties predict FM rate selectivity: sideband inhibition and duration tuning. Sideband inhibitio...

SECTION ASSIGNEMENT Neuropharmacology This article has not been copyedited and formatted. The final version may differ from this version. ABSTRACT The present study was planned to investigate the action of pregabalin on voltage-dependent Ca 2+ channels (VDCC) and on novel targets (fusion pore formed between the secretory vesicle and the plasma membrane, exocytotic machinery and mitochondria) th...