A bone scan uses radioactive tracers, which are injected into your bloodstream. Use of these radioactive tracers is strictly controlled. Conservative solutes are often used as hydrologic tracers for water movement and transport. An extensive list of radioactive tracers used in hydraulic fracturing can be found below. Five Nobel laureates have been intimately involved with the use of radioactive tracers in medicine. I are used as hydrological tracers. Such cysts can be identified with nuclear imaging combined with specific tracers, such as sestamibi. This assertion was validated by Rudolf Schoenheimer's work with radioisotopes as tracers in 1937. The government contracted match factories to manufacture gunpowder and pyrotechnic fillers like tracers. The first and most widely used tracers are sunspots. His aircraft ran through my tracers, and I saw several explosions on it. Now gun flashes, tracers, and star shell candles stained the inky darkness. Now gun flashes, tracers, and star shell candles stained the black inky darkness. This basic technique may be enhanced significantly by the use of glucose tracers. The first automatic lathes were mechanically automated and controlled by cams or tracers and pantographs.