A folding knife incorporates an opening assist mechanism that functions to drive the blade from the closed to the open position. In the method, the fluorochemical surfactant is recovered by subjecting the aqueous solution containing the fluorochemical surfactant to a filtration treatment step with a reverse osmosis membrane so as to obtain from the aqueous solution, a concentrated aqueous solution in which the concentration of the fluorochemical surfactant is increased. The legacy long training field and the N\u22121 high throughput long training fields can be transmitted in N time slots using an N\xd7N orthogonal matrix, such as a Walsh matrix or a Fourier matrix. The tools may also provide glyph substitution tables that include Unicode fields for storing Unicode representations of characters, along with first and second glyph fields for storing glyphs of the characters. The mattress is supported by an air filtration foundation capable of creating an air flow within the mattress. Such a preparation can be sued in the prophylaxis andor treatment of a medical condition.