An improved method for controlling intraocular pressure during ophthalmic surgery. The latch interlocks with a stop on the coupling body to provide a passive lock when the arm is closed. The validity of the signal is determined based on at least of a number, a spacing, and a magnitude of the frequency domain peaks in the transformed signal. The semiconductor material slices can be between front gates and back gates. The rank aggregation system then learns weights for each of the ranking sources by attempting to optimize the difference between the relative rankings of pairs of entities using the weights and the relative rankings of pairs of entities of the training data.