Methods of prognosis and of prophylactic and therapeutic treatment of tumors based on the involvement of galectin-1 and galectin-4 in tumor development are described. In one embodiment, the ESD clamp includes: a silicon controlled rectifier ; and a trigger circuit for providing a tunable trigger voltage to turn on the SCR, the trigger circuit including a metal-insulator transition material. Values of the components of the circuitry may be selectively and independently chosen to synthesize a variable range of negative capacitance and thus produce a negative capacitance approximately equal in magnitude to a unique capacitance associated with the bondpad of a variety of integrated circuits. The circuit simulator employs fault sensitivity analysis for amenable cells for greatly accelerated fault detection. The devices can be operated to dispense liquid in response to input of an identification code which is generated when the user prepays, for example through a web interface, a mobile application, a point of sale tool, or a tablet application. A system and method of evaluating pulmonary embolism in a subject may include measuring end tidal partial pressure of exhaled carbon dioxide in the subject, wherein the measurement is made orally, obtaining a clinical approximation of dead space ventilation based on the measurement, and excluding pulmonary embolism when the end tidal partial pressure of exhaled carbon dioxide reaches a threshold.