The present invention provides methods for lysing a thrombus or ablating a mass in a subject by administering a plurality of biodegradable nanoparticles and delivering ultrasound to the subject. Embodiments include systems and methods for translating Ethernet Passive Optical Network upstream time grants to OFDMA resources represented by individual subcarriers of an upstream OFDMA frame. The burst length regulating block sets a second burst length at a test mode which is longer than a first burst length at a normal mode.