Filament is a continuous strand consisting of anything from 1 filament to many. "Filament notching" is due to uneven evaporation of the filament. These tubes instead operate with high negative voltages on the filament and cathode. Consider a tungsten light-bulb filament. Light loss is due to filament evaporation and bulb blackening. Precursor compositions and mechanical processes used during spinning filament yarns may vary among manufacturers. This is a cathode that is not heated by a filament. Actin nucleation is an initial step in the formation of an actin filament. The heated filament emits light that approximates a continuous spectrum. The titin protein is located between the myosin thick filament and the Z disk. The tungsten filament lasted longer and gave brighter light than the traditional carbon filament. All magnetrons contain a small amount of thorium mixed with tungsten in their filament. Edison began commercial production of carbon filament bulbs in 1880. Crossbridge cycling is a sequence of molecular events that underlies the sliding filament theory. GE's efforts came to fruition with the invention of a tungsten-based filament.