A method for identifying antibacterial agents comprises depleting bacteria of a strain comprising a luxAB construct of Ca2+, incubating the Ca2+ depleted bacteria with an agent the antibacterial effect of which shall be determined, recording the light emitted by the bacteria upon addition of an aldehyde, the incubation being carried out at a temperature which is at least 10\xb0 C. The evaluated system configuration may include various types of software and hardware components which may impact the operations of the computer system. Responsive to a request for a Java object from an application server, e. The intermediate cylindrical tube is fixed to the control tube and rotatable around the outer cylindrical tube. The printer can periodically estimate the remaining life of the cartridge using a reference print material level and the change in pixel count since the print material was at the reference material level.