SELECTIVE OVERHEATING OF SINGLE CELLS IN BIOLOGICAL TISSUES BY MEANS OF ULTRASHORT-WAVE PERMEATION
H. Schaefer, H. Schwan · 1947
A 1947 theoretical and experimental analysis found that ultrashort-wave permeation selectively overheats macroscopic objects but not microscopic particles such as single cells.
Plain English Summary
This 1947 study by H. Schaefer and H. Schwan examined the conditions under which ultrashort-wave permeation can produce selective heating of single cells in biological tissues. It confirms that selective overheating occurs for macroscopic objects but not for microscopic particles, where the excess temperature depends greatly on particle size and cannot reach even one thousandth of a degree. Practical conditions would require extraordinarily high field intensities of about 2 kV/cm.
Why This Matters
This 1947 study examines whether ultrashort-wave permeation can selectively overheat single cells such as bacteria or blood cells, a question that drew much attention in the early stages of ultrashort-wave therapy. The authors' theory confirms the positive results on macroscopic objects, such as small fish in the field of a strong oscillator, and the negative results on microscopic particles, such as yeast cells and paramecia.
For a 20-micron particle, a 1 degree excess temperature requires a field intensity of 2 kV/cm, which would produce a rapid temperature rise of more than 100 degrees per second even in tissue with poor conductivity and cannot technically be produced over large areas of the body. The authors found that earlier positive results in bacterial cultures cannot be explained by direct selective overheating of individual bacteria. They offer two possible interpretations, aggregate formation of bacteria into groups or an additional unknown effect, and state that there are no concrete indications for specific athermic effects.
Finding
The theory did not, however, confirm the numerous positive effects reported in bacterial cultures (Haase and Schliephake (1). This discrepancy will be taken up below.
In their words
“The theory did not, however, confirm the numerous positive effects reported in bacterial cultures (Haase and Schliephake (1). This discrepancy will be taken up below.”
Figures from the Original Paper
Diagram extracted from the original research document.
Study Details
To investigate the conditions under which ultrashort-wave permeation can produce selective heating of single cells in biological tissues, specifically examining the theoretical and experimental feasibility of selective overheating of individual bacteria or cells.
The study presents a mathematical theory of selective heating based on analysis of heat distribution...
The study confirms that selective overheating occurs for macroscopic objects but not for microscopic...
The phenomenon of selective overheating is highly dependent on particle size. Macroscopic effects are possible while microscopic particle heating does not achieve significant temperature elevation. The theoretical framework confirms that while the process can theoretically produce temperature differences, practical implementation requires field intensities that are technically unfeasible for large area treatment. The discrepancy between theoretical predictions and experimental observations in bacterial cultures suggests either aggregate formation or unknown non-thermal effects.
Show BibTeX
@article{selective_overheating_of_single_cells_in_biological_tissues_by_means_of_ultrasho_g6888,
author = {H. Schaefer and H. Schwan},
title = {SELECTIVE OVERHEATING OF SINGLE CELLS IN BIOLOGICAL TISSUES BY MEANS OF ULTRASHORT-WAVE PERMEATION},
year = {1947},
}