Various embodiments of abrasive jet cutting systems are disclosed herein. Further, pharmaceutical compositions for the treatment of gastro-enteritis including -lactalbumin as active compound are described. This electronic part is equipped with a precharge circuit which raises the output power control voltage to produce a predetermined level of output power, while detecting a current flowing through a final-stage power amplifying element, triggered by rise of a supply voltage at start of transmission. During a visit to the client location, a second biometric signature of the healthcare worker is captured. Once consent is indicated, it is communicated from the individual’s computer to another computer such as a server over, for example, a modem connection. The invention can be used, for example, for leak-off control or fluid diversion purposes.