Parvovirus B19. Parvovirus B19 infections in children present as a viral exanthema, and in adults as a cause of arthralgia and arthritis. The incubation period is 7â10 days with non-specific flu-like symptoms in the first week followed by arthralgias or arthritis in up to 60% of patients in the second week.
Variable Torque Motors - American Made Efficiency. One of the largest down-sides to electric motors is their inherent efficiency range and, in hybrid systems, the drag they can create on the drive train.
Variable-frequency drive. A variable-frequency drive (VFD; also termed adjustable-frequency drive, variable speed drive, AC drive, micro drive or inverter drive) is a type of adjustable-speed drive used in electro-mechanical drive systems to control AC motor speed and torque by varying motor input frequency and voltage.