The goal is to help create smooth energy-optimal monophasic pulse waveforms for defibrillation using the Luo-Rudy cardiomyocyte membrane computer model. The waveforms were described with the help of the piecewise linear function. Each line segment provides a transition from one present level of the transmembrane potential to the next with a minimal energy value. The duration of the last segment...

was used to deliver rectangular pulses for extracellular field stimulation of individual heart cells. We found that single frog and guinea pig ventricular myocytes are excitable with rectangular pulse field stimulation over a wide range of pulse durations, ranging from 10 msec to as little as 20 ,usec. The excitation field strength varies inversely with pulse duration as described by the Weiss-...

We report on the experimental results of 300 nm features generated on fused silica using a near-infrared (IR) femtosecond laser pulse initiated by an ultraviolet (UV) pulse. With both pulses at a short (~60 fs) delay, the damage threshold of the UV pulse is only 10% of its normal value. Considerable reduction of UV damage threshold is observed when two pulses are at ± 1.3 ps delay. The damage f...

The effects of pulse rate on intensity discrimination were evaluated in 14 subjects with Clarion C-I cochlear implants. Subjects had a standard [Clarion spiral electrode array (SPRL group)] or perimodiolar electrode array [Clarion HiFocus electrode array with electrode positioning system (HF+EPS group)]. Weber fractions for intensity discrimination [ Wf(dB)= 10 log deltaI/I] were evaluated at f...

BACKGROUND Some studies suggest better overall outcomes when right unilateral electroconvulsive therapy (RUL ECT) is given with an ultrabrief, rather than brief, pulse width. METHODS The aim of the study was to test if ultrabrief-pulse RUL ECT results in less cognitive side effects than brief- pulse RUL ECT, when given at doses which achieve comparable efficacy. One hundred and two participan...

By applying a voltage pulse to a scanning tunneling microscope tip the surface under the tip will be modified. We have in this paper taken a closer look at the model of electric field induced surface diffusion of adatoms including the van der Waals force as a contribution in formations of a mound on a surface. The dipole moment of an adatom is the sum of the surface induced dipole moment (which...

OBJECTIVE To evaluate the quantitative advantage of double pulses vs. single pulses in TMS phosphenes evoked from the occipital cortex. METHODS In 10 healthy subjects single pulse thresholds were compared with thresholds from double pulses of equal strength at a stimulus onset asynchrony (SOA) of 2, 5, 10, and 20ms, both with biphasic and monophasic pulse forms. In a second experiment fusion ...

SUZUKI, H. Effects of a Benzodiazepine Antagonist, Ro 15-1788, on Hippocampal Field Potentials in Freely Moving Rats. Tohoku J. Exp. Med., 1991, 165 (4), 261-270 Effects of a benzodiazepine receptor agonist (diazepam) and an antagonist (Ro 15-1788, flumazenil) administered separately or in combination on field potentials recorded from the hippocampal dentate area were examined in unanesthetized...

An undulator is proposed based on the plasma wakefields excited by a laser pulse in a plasma channel. Generation of the undulator fields is achieved by inducing centroid oscillations of the laser pulse in the channel. The period of such an undulator is proportional to the Rayleigh length of the laser pulse and can be submillimeter, while preserving high undulator strength. The electron trajecto...

[1] To better understand the asymmetric distribution of microearthquake aftershocks along the central San Andreas fault, we study dynamic models of slip-weakening ruptures on an interface separating differing elastic half-spaces. Subshear ruptures grow as slightly asymmetric bilateral cracks, with larger propagation velocities, slip velocities, and normal stress changes at the rupture front mov...