The tran-scription factor CF2 is a mediator of EGF-R-activated dorsoventrai patterning in Drosophila

A composition is disclosed of malonic acid, a resinous carrier, and a solvent. The composition is applied to a portion of an electrical apparatus which is exposed to a fluid stream. The solvent in the composition is evaporated to produce a thermo-particulating coating. When the electrical apparatus overheats the malonic acid in the coating forms particles in the fluid stream which are detected by a monitor.