Abstract: A multi-well assembly according to one embodiment comprises a multi-well block and a guide plate. The multi-well block defines a plurality of wells, with each well having a fluid-impermeable bottom surface. The guide plate defines a plurality of fluid passageways corresponding to the wells of the multi-well block. The guide plate is configured such that, whenever the guide plate is registered with the multi-well block, fluid communication is established between each well and an associated fluid passageway. The guide plate enables iterative chemical or biological processes using multiple multi-well blocks. A seal plate is configured to cut fluid communication conferred by the guide plate via registration with the guide plate, or via registration with the multi-well block (once the guide plate is removed). The seal plate allows iterative chemical or biological processes within a single multi-well block.

Abstract: Apparatus for aligning the optical systems of a lamphouse and a movie projector in the form of a laser alignment tool having a single beam laser with a diffraction grating to split the beam into multiple beams and the laser diode module is housed in a cylindrical casing. The diffraction grating splits the single laser into a specific number of beams of equal intensity, consisting of a center beam and each of the beams to either side of it at equal angles. The laser alignment tool has a geared motor with an adjustable speed which rotates the diffraction grating so that each angled beam sweeps a concentric circle with respect to the other beams. The diffraction grating is interchangeable so that the laser alignment tool can be used for lamphouse systems with varying focal lengths or for other applications such as reflector inspection. The motor may be turned on or off while the laser is kept on. The speed of rotation of the beams is controlled by varying the voltage to the motor.