Abstract: The present disclosure is directed to a dual-mode control circuit for a microelectromechanical system (MEMS) gyroscope. A control circuit is coupled to a Lissajous frequency modulated (LFM) gyroscope to control amplitude of oscillation of a mass along two directions. The amplitude of oscillation is controlled by an automatic gain control (AGC) loop which allows the same amplitude of oscillation in both directions. An AGC is implemented with a combination of proportional control (P-type) and integral control (I-type) paths that maintain the correct Lissajous pattern of the oscillation of the mass. The AGC may include a dual-mode stage which is able to switch between a P-type control path and an I-type control path based on the operation of the LFM gyroscope. A fast start-up phase may be controlled by the P-type control path while the I-type path is pre-charged to be ready to use in a steady state condition.

Abstract: Type I collagen gel with an H.sub.2 O content not exceeding 20% by weight, in the form of a sheet of thickness between 0.02 and 2 mm, of compact transparent structure, with a capacity for absorbing aqueous biological liquids limited to a maximum of 15 times its weight, being free from native collagen degradation products, and suitable for the therapeutic treatment of wounds and burns.

Abstract: A process is described for producing pure crystalline products, in particular penicillin and cephalosporin, wherein the desired product, prepared according to a known method, is treated with ethanol in one or two steps, whereby the crystallization of the pure product and impurity separation are achieved.

Abstract: A process for preparing rifamycin S from rifamycin O. Rifamycin O is dissolved in a mixture of an organic solvent and an alcohol at room temperature. The rifamycin O is then hydrolyzed with a mineral acid and the thus obtained rifamycin S is purified by crystallization.