This invention provides for labeling reagents, labeled targets and processes for preparing labeling reagents. The pump head rollers are mounted radially from the axis of rotation of the pump motor and compress the elastomeric flow channels against the rigid substrate. Additionally, such opto-electronic modules may include illuminating optics, imaging optics, andor image manipulation and processing elements. The projection is lower than an engaging portion and is movable along the longitudinal direction between the engaging portion and the leading end of the pen shaft. The notifications may also be annotated with compensation data that defines the financial terms under which the notifications may be provided to others.