In a line-type printer head, a plurality of head chips are arranged side by side in a printing direction, and each of the head chips has a plurality of discharging portions aligned in the printing line direction so as to discharge ink droplets. Because the host based caching may make use of knowledge about what data is being cached, improved performance may be achieved in some cases. In other embodiments, the inventors have shown that there is improved Ad-p53 production with cells grown in serum-free conditions, and in particular in serum-free suspension culture. A couch on which a patient is lying is moved until a tumor substantially reaches an extension of an ion beam path in the irradiating unit.