Work of the motor units in human antagonists during rhythmic movements.

Firing of single motor units (MUs) from m. biceps brachii and m. triceps brachii has been studied with rhythmic successive flexion and extension in the elbow.

Variability of the interimpulse intervals of motor units upon voluntary activation.

Twenty subjects were investigated for voluntary control of separate motor units (MU) in the biceps brachii muscle under visual and auditory feedback. After 20-fold repetition of the task for sustaining stable firing frequency it turned out that in every trial the frequency was different and the variability of the interimpulse intervals changed in an unexpected way. It increased with the lengthening of the interimpulse intervals, but in an uneven manner.

Disinfectant effect of performic acid.

1. Performic acid applied at short exposures to various kinds of microorganisms known for their resistance shows a strong bactericidal and sporicidal effect. 2.