Abstract: A ventilated shoe or insole having a uniform and continuous air channel extending from the heel portion of the sole portion or insole to the toe portion and opening, at the rear end thereof, into the air space outside the shoe or outside the insole, and at the front end thereof, into the inside of the shoe or onto the upper surface of the insole. According to the invention, the air channel is a channel formed by an elastic supporting structure and having a substantially standard cross section that as the stepping motion proceeds, closes tightly phase by phase substantially along the entire stretch thereof under the weight of the foot for transferring air according to the hose pump principle from outside of the shoe or insole into the inside of the shoe or into the upper surface of the insole along the air channel.

Abstract: A packing element for a biological filter or for use in mass transfer has a plurality of trickling faces along which the liquid or gas to be treated flows. The faces are disposed on at least one rim of the element at an angle between 3.degree. and 40.degree. relative to the vertical axis of the element, and have relatively large surface areas. The apex angle of the element is about 140.degree. to about 180.degree., the height of the element being greatest at its center portion. Rounded projecting portions cause randomly introduced elements to become oriented automatically so that the vertical axis is aligned with the liquid or gas flow and the element in a horizontal position. Additionally, a ductlike member is provided at the upper edge on at least one of the at least one rims, to more effectively distribute the liquid or gas flow on the trickling faces.