Abstract: A lock operated by the introduction of a coin into a chamber in the lock. A scanning member scans the size of the introduced coin. The scanning member includes at least one recess for receipt of a releasing member adapted to move into said recess to cause release of a locking member to permit removal thereof from the lock.

Abstract: In a method of separating bacteria from a bacteria containing liquid sample by means of a dish-like centrifuge container (21) having an upper opening (25) defined by a radially inwardly extending rim portion (24), the following sequential steps are carried out. The centrifuge container is rotated at a high rotational speed. A volume of a high density component of a density higher than the density of the bacteria is introduced into the centrifuge container, whereupon a volume of a low density component having a density lower than the density of the bacteria is introduced into the container so that a two component gradient separation layer (60) comprising a high density layer (61) and a low density layer (62) is formed within the centrifuge container (21).