Abstract:
:Two mechanisms for the interaction of alternating electrical fields with biological tissue are the development of heat, via i(2)R losses, and field-induced force effects, via differences in passive electrical properties. It has been shown that for continuous wave (CW) fields in media of physiologic electrical conductivity, the development of heat (>1 degrees C) always precedes the possible appearance of a field-induced force effect. Using pearl-chain formation as a model effect and experimentally demonstrating that its time constant varies inversely as the square of the electrical field strength, we show that a pulsed field has no greater ability than a CW field of equal rms field strength to produce a field-induced force effect. Thus, the statement above for CW fields can be broadened to include pulsed fields of any description. By relating incident power density to electric field strength in tissue, we show that the American National Standards Institute's radiation protection guide obviates the production of genetic effects in man, if they exist, via field-induced force effects.
journal_name
Biophys Jjournal_title
Biophysical journalauthors
Sher LD,Kresch E,Schwan HPdoi
10.1016/S0006-3495(70)86346-9subject
Has Abstractpub_date
1970-10-01 00:00:00pages
970-9issue
10eissn
0006-3495issn
1542-0086pii
S0006-3495(70)86346-9journal_volume
10pub_type
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