A filter-holder for use in coffee machines, comprising: a cup in which a filter containing the coffee is inserted; at least one delivery spout; and a valve associated with the delivery spout for stabilizing the infusion back-pressure. The difference in ink flow between the supply and return is delivered to the application rollers of a printing press. 1nonane derivatives, pharmaceutical compositions comprising such derivatives and methods of using such derivatives to treat disease states, disorders and conditions mediated by opioid receptors. The same types of impedance elements as the impedance element are interposed in the first and second transmission lines between the first circuit block and the second circuit block.