A method and system are provided for determining a condition of a selected region of epithelial tissue. The collet adaptor has a body or arbor with a cylindrical bore for receiving a cylindrical portion of the collet and a tapered surface at its front end for engagement with a tapered split head portion of the collet. The structure also contains a liquid spray system to spray insecticide and deodorant onto the landfill and a fire retardant system which is activated automatically when smoke is detected. According to the invention, the magnet assembly is used for actuating a closing element in a magnet valve. 7, provided that the absorbance of the dyed layer is controlled so that it does not become less than 0. The collecting line has a multiplicity of openings spaced apart in its longitudinal direction.