An apparatus for low-damage, anisotropic etching of substrates having the substrate mounted upon a mechanical support located within an ac or dc plasma reactor. An example apparatus to determine a saturation pressure of a fluid includes a housing having a detection chamber and a heater assembly partially positioned within the detection chamber to heat a fluid. Methods of identifying an agent that modulates intracellular calcium, methods to screen for an agent that modulates NFAT regulator function, methods to diagnose unexplained immunodeficiency in a subject, and methods for identifying an agent for treating or preventing a disease or disorder associated with a NFAT regulator protein or calcium signaling are also disclosed. In one embodiment, the re-sequencing methodology of the present invention adapts to the transmission delays across the bonded communications path.