Cochlea a protein motor called prestin on their outer membranes; it generates additional movement that couples back to the fluid–membrane wave. This "active amplifier" is essential in the ear's ability to amplify weak sounds. The active amplifier also leads to the phenomenon of soundwave vibrations being emitted from the cochlea back into the ear canal through the middle ear (otoacoustic emissions). Otoacoustic emissions are due to a wave exiting the cochlea via the oval window, and propagating back through the middle ear to the eardrum, and out the ear canal, where it can be picked up by a microphone. Otoacoustic emissions
Jock Stirrup resources that Iraq had posed until 2008, Stirrup believed that by 2009 NATO forces were successfully taking the fight to the insurgents, driving them out of towns and villages and thereby allowing governance to improve which would lead to the defeat of the insurgency. Speaking generally on operations in Afghanistan, Stirrup has noted that whilst "the military is a key, an essential element in dealing with those problems, but by and large these problems can only be resolved politically" and that he favoured a pragmatic approach to dealing with former members of the Taliban. By December 2009, Stirrup was expressing