The mechanism of inward rectification was examined in cell-attached and inside-out membrane patches from Xenopus oocytes expressing the cloned strong inward rectifier HRK1. Little or no outward current was measured in cell-attached patches. Inward currents reach their maximal value in two steps: an instantaneous phase followed by a time-dependent "activation" phase, requiring at least two expon...

We report an experimental study of femtosecond optically excited emission of terahertz frequency electromagnetic radiation from GaxIn1−xAs bulk crystals with alloy composition in the range between 0 x 0.65. The terahertz-emission mechanisms in bulk GaxIn1−xAs were studied as a function of carrier mobility, carrier concentrations, band gap as well as polycrystal grain size. Our experiments and a...

How spatial and temporal information are integrated to determine the direction of cell migration remains poorly understood. Here, by precise microfluidics emulation of dynamic chemoattractant waves, we demonstrate that, in Dictyostelium, directional movement as well as activation of small guanosine triphosphatase Ras at the leading edge is suppressed when the chemoattractant concentration is de...

In this paper, an algorithm for rectifying heterogeneous and uncalibrated pairs of stereo images is presented. In particular, a pair of images is captured by using a combination of static and dynamic cameras at unequal zoom, thus having different focal lengths and/or image resolutions. The rectification of such pairs of images is made in two steps. In the first step, image shrinking based on fo...

We propose a new rectification method for aligning epipolar lines of a pair of stereo images taken under any camera geometry. It effectively remaps both images onto the surface of a cylinder instead of a plane, which is used in common rectification methods. For a large set of camera motions, remapping to a plane has the drawback of creating rectified images that are potentially infinitely large...

The characteristics of the cell membrane seem to be of primary importance in the case of both conduction and contraction. Among the membrane qualities recently discovered is electrical rectification; ~z., the ability of the membrane to permit electrical current to pass more easily outward than inward (Cole and Curtis, 1941; Guttman and Cole, 1941). The present paper constitutes an at tempt to s...

The effect of glycerol treatment on the membrane currents and tension development was studied in voltage clamped snake muscle fibers. In muscle fibers which were exposed for 1 h to a normal saline containing 400 mM glycerol and then returned to a normal medium, graded depolarizations did not accompany contractile responses. However, when the fiber was depolarized to a certain level, an incremen...

The ionic current rectification (ICR) is studied theoretically by considering a pH-regulated, conical nanopore. In particular, the effect of electroosmotic flow (EOF), which was often neglected in previous studies, is investigated by solving a set of coupled Poisson, Nernst-Planck, and Navier-Stokes equations. The behaviors of ICR under various conditions are examined by varying solution pH, bu...

We investigated a mechanism of rectification in diblock oligomer diode molecules that have recently been synthesized and showed a pronounced asymmetry in the measured I-V spectrum. The observed rectification effect is due to the resonant nature of electron transfer in the system and the localization properties of bound state wave functions of resonant states of the tunneling electron interactin...

We present an efficient method for character skew rectification in scene text images. The method is based on a novel skew estimators, which exploit intuitive glyph properties and which can be efficiently computed in a linear time. The estimators are evaluated on a synthetically generated data (including Latin, Cyrillic, Greek, Runic scripts) and real scene text images, where the skew rectificat...