Constructing More Accurate Phylogenetic Trees for Highly Divergent Sequences using ClustalW.

A dual purpose suction cleaning apparatus includes an open-topped container adapted for the collection of a liquid and a motor driven air suction unit for applying suction to the container. In use, either a detachable reservoir unit, or a detachable connector member is interposed between the air suction unit and the container so that in the one case the apparatus serves as a water extraction cleaner, whereas in the other case it operates as a normal dry vacuum cleaner. The inter-changeable reservoir unit and connector member are each formed as self-contained units by means of which the exhaust air flow from the suction unit is directed by the reservoir unit so as to displace liquid therefrom, but is diverted to atmosphere by the connector member. A filter element for dry dust collection may be incorporated in the connector member or a separate dust collecting bag may be provided in the container.