The two photocells are linked to the Tree: the Pre-Stage, and the Stage lights. When the car inches forward and blocks the first photocell, the Pre-Stage light comes on, indicating that the driver is close to the starting line. Most tracks have a rollout, or distance between the Pre-Stage and Stage beams of 6-8.
Batten disease is named after the British pediatrician Frederick Batten, who first described it in 1903. Also known as Spielmeyer-Vogt-SjÃ¶gren-Batten disease, it is the most common form of a group of disorders called neuronal ceroid lipofuscinosis (or NCLs).
Hyperthyroidism (Thyrotoxicosis) Graves-Basedow disease is named after the Irish physician (Robert Graves) and the German physician (Karl von Basedow) who described several cases in 1835 and 1840. It was actually first described by Parry a few years earlier. In Europe the disease is known as Basedowâs disease.