Tympanic membrane retraction used to manage tympanic membrane retraction, with the aims of preventing or relieving hearing loss and cholesteatoma formation. As retraction pockets may remain stable or resolve spontaneously, it may be appropriate to observe them for a period of time before considering any active treatment. The Valsalva maneuver increases middle ear pressure and can push a retracted eardrum out of the middle ear if is not adherent to middle ear structures. Hearing may improve as a result, however it can be a painful maneuver. The benefits are typically only temporary. Middle ear pressure can also be increased by Politzerization and with
Membrane gas separation can be economically competitive with older and more common technologies such as amine-based absorption. Currently, both membrane and amine-based absorption processes can be designed to yield a 90% CO capture rate. For carbon capture at an average 600 MW coal-fired power plant, the cost of CO capture using amine-based absorption is in the $40–100 per ton of CO range, while the cost of CO capture using current membrane technology (including current process design schemes) is about $23 per ton of CO. Additionally, running an amine-based absorption process at an average 600 MW coal-fired power plant consumes about 30% of the