PURPOSE The h current (I(h)) is a hyperpolarization-activated current that plays important roles in the physiological functions of different types of cells. In the retina of lower vertebrates, I(h) contributes to the rod responses to light stimuli by bringing the membrane potential back to the dark level in the presence of continuous light. The purpose of this study was to determine how dopamin...

Inactivation of slow Ca2+ channels was studied in intact twitch skeletal muscle fibers of the frog by using the three-microelectrode voltage-clamp technique. Hypertonic sucrose solutions were used to abolish contraction. The rate constant of decay of the slow Ca2+ current (ICa) remained practically unchanged when the recording solution containing 10 mM Ca2+ was replaced by a Ca2+-buffered solut...

We introduce a method that permits faithful extraction of the decay time course of the synaptic conductance independent of dendritic geometry and the electrotonic location of the synapse. The method is based on the experimental procedure of Pearce (1993), consisting of a series of identical somatic voltage jumps repeated at various times relative to the onset of the synaptic conductance. The pr...

Abstract: This paper studies the development and decay of surface discharge under various voltage waveforms and electrode shapes in air at atmospheric pressure. The electro-optical Pockels method is utilised to measure and quantify the distribution of surface charge. Charge is deposited on the surface of the Bismuth Silicon Oxide (BSO) sensing crystal from a high voltage needle or mushroom elec...

The permeability or crossover characteristics of a typical perfluorosulfonic acid base type membrane are used for the temporal and spatial estimations of nitrogen concentration along the anode channels of a polymer electrolyte membrane fuel cell stack. The predicted nitrogen accumulation is then used to estimate the impact of local fuel starvation on stack voltage through the notion of apparent...

In this paper, we present the direct observation of quantum size effects (QSE) on the work function in ultrathin Pb films. By using scanning tunneling microscopy and spectroscopy, we show that the very existence of quantum well states (QWS) in these ultrathin films profoundly affects the measured tunneling decay constant kappa, resulting in a very rich phenomenon of "quantum oscillations" in ka...

In recent decades, fuel cells have been widely used in energy generation. In a PEMFC, considering the specific application, two types of oxidants are used. Durability tests, which are highly costly products,  are of crucial importance in evaluating the lifetime of fuel cells. The purpose of the present paper is to investigate the performance of a fuel cell by changing the type of oxidant from a...

Diffusion of metal atoms onto a molecular monolayer attached to a conducting surface permits electronic contact to the molecules with minimal heat transfer or structural disturbance. Surface-mediated metal deposition (SDMD) involves contact between "cold" diffusing metal atoms and molecules, due to shielding of the molecules from direct exposure to metal vapor. Measurement of the current throug...

This paper provides a complete physical picture of optical response time as a function of cell gap (d) in a wide voltage regime. Normally both rise and decay times are known to be proportional to d in the small angle approximation (Vth < V < ffiffiffi 2 p Vth), and in the high voltage regime where Vp < V < Vi the optical decay time is independent of d. In this paper, we found that between these...

the goal of this study was to determine the effects of the l-type calcium channel blockers verapamil and diltiazem on the currents of voltage-gated potassium channel (fkv1.4δn), an n-terminal-deleted mutant of the ferret kv1.4 potassium channel. measurements were made using a two electrode voltage clamp technique with channels expressed stably in xenopus oocytes. the fkv1.4δn currents displayed...