An electric control system for a pulse width modulated inverter connected in parallel to an electricity distribution network for correcting or minimizing a voltage total harmonic distortion of the distribution network includes a sampler of the voltage of the electricity distribution network for obtaining samplings of the distribution network. A first strip on the substrate has a first surface wettability and a second strip on the substrate has a second surface wettability different from the first surface wettability. The systems and methods hold the blood collection tube a predetermined radial distance from the incident light source where a linear relationship exists between sensed reflected light measured by the optical sensor and red blood cell hematocrit in a range of at least 10 to 90. 150<4\xd7\u03c0\xd7D\xd7\u03bcava,T=7000<400<1>. The light projection system can include a light intensity sensor in an image path, in a light-source subsystem light-dump path, in a light-modulation subsystem light-dump path, in a position to measure light leaked from optical components, or combinations thereof. The delivery of individual V-pulses to the heart of the patient may be timed relative to the ends of individual far-field atrial events.