Fifteen adult mongrel dogs underwent two-stage occlusion of the midor distal left anterior descending coronary artery and then a reperfusion stage. The dogs were studied 3-30 days later to determine strength-interval relations in a canine model of chronic myocardial infarction. These dogs were susceptible to the initiation of sustained ventricular tachyarrhythmias with the introduction of one, ...

Fifteen adult mongrel dogs underwent two-stage occlusion of the mid- or distal left anterior descending coronary artery and then a reperfusion stage. The dogs were studied 3-30 days later to determine strength-interval relations in a canine model of chronic myocardial infarction. These dogs were susceptible to the initiation of sustained ventricular tachyarrhythmias with the introduction of one...

Electronic retinal prostheses represent a potentially effective approach for restoring some degree of sight in blind patients with retinal degeneration. However, levels of safe electrical stimulation and the underlying mechanisms of cellular damage are largely unknown. We measured the threshold of cellular damage as a function of pulse duration, electrode size, and number of pulses to determine...

In this research, the performance of ultrasonic pulse velocity (UPV) in concrete is examined as a nondestructive experiment in order to estimate mechanical (compressive and tensile strength) and durability (water absorption) properties of fiber-reinforced self-compacted concrete For this purpose 11 mixture designs containing 3 types of fibers (steel: 0.1, 0.2, 0.3 and 0.4 percent by volume, Pol...

Introduction: Electroporation is a practical technique used to transport the molecules across the cell membrane. The utilization of fluorescent molecules is the method widely used to evaluate the electropermeability of cell membrane as a result of pulse application. It is also possible to use mathematical methods to predict the changes caused in cell electropermeability as a result of the chang...

Treatment of erythrocyte ghosts in random positions in a suspension with membrane fusion-inducing direct current electric field pulses causes the membranes to become fusogenic. Significant fusion yields are observed if the membranes are dielectrophoretically aligned into membrane-membrane contact with a weak alternating electric field as much as 5 min after the application of the pulses. This d...

The effect of subthreshold depolarization on mechanical threshold was investigated in tetrodotoxin-poisoned mammalian and amphibian skeletal muscle fibers using a two-microelectrode voltage-clamp technique. Mechanical threshold was determined with a 2-ms test pulse. The immediate effect of depolarization was inhibition of the mechanical system. The consequent increase in the test pulse threshol...

Double light pulse resolution required longer inter-pulse time intervals of short duration of the pulse. The threshold of double pulse discrimination was not contingent upon the actual phase of cardiac or respiratory cycle.