Methods of generating cell lines with a sequence variation or copy number variation of a gene of interest, methods of use thereof, and cell lines with a sequence variation or copy number variation of a gene of interest are provided. In the method, at least first data is determined, which is at least one of the following: the power input in the actuator, the crushing force, the particle distribution of the crushed material produced by the crusher, or the quantity of crushed material produced by the crusher. A seat is mounted to the frame to support the user using the crankset in the pedaling actuation. A retrofit element may include a light-affecting material arranged to span across a portion of a light output surface or area of a lighting device and structure arranged for removable attachment to the lighting device.