A micro-radiation therapy apparatus includes an isotope-based micro-radiotherapy brachytherapy small animal irradiator useful for radiating a biological system, the irradiator having an external radiation source proximate the biological system comprising a collimated radiation beam. An insulation layer for impedance value adjustment is formed throughout a principal surface of a first magnetic substrate. The multiple integrated circuit chip structure has an interchip interface circuit to selectively connect internal circuits of the integrated circuits to test interface circuits having ESD protection circuits and inputoutput circuitry designed to communicate with external test systems during test and burn-in procedures. The information may be transmitted to one or more servers. The flow of liquid through the capillary restriction, the pressure variation rate and known dimensions of the system can be used typically by a processor to determine a rheological property of a fluid.