Direct current shock pulses

For ventricular tachycardia in patients without a pulse, immediately give a precordial thump or apply synchronized direct-current countershock at 1-3 J/kg. If this is not successful, begin CPR and apply countershock at 3-5 J/kg administer amiodarone and/or lidocaine and repeated counter-shocks as recommended in ACLS guidelines. 

Attempts to collect eggs and sperm should be made between 9 pm and 1 am. Either place beakers of animals in the dark, or (more reliably) use a stimulator to give a brief (2-s) nonlethal shock of direct current (50 V in 10-ms pulses) to a beaker of animals. 

Nonlinear properties of normal dielectrics can be studied in the elastic regime by the method of shock compression in much the same way nonlinear piezoelectric properties have been studied. In the earlier analysis it was shown that the shape of the current pulse delivered to a short circuit by a shock-compressed piezoelectric disk was influenced by strain-induced changes in permittivity. When a normal dielectric disk is biased by an electric field and is subjected to shock compression, a current pulse is also delivered into an external circuit. In the short-circuit approximation, the amplitude of this current pulse provides a direct measure of the shock-induced change in permittivity of the dielectric. 

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