Fig. 1From: Low-frequency ultrasound for pulmonary hypertension therapy a Ultrasonic transducer with a cut-out (1) and flat (2) surfaces with laboratory-made controller (3); b layout of the ultrasonic transducer with a cut-out surface: 4—ring-shaped piezoelectric element, 5—back mass, 6—front mass, 7—a preload bolt, 8—copper-nickel electrodesBack to article page