Devices and methods comprise or provide an ECG recording device containing a mailable base and electrode assembly andor other means engageable with the base to receive ECG signals from a subject during a self-administered ECG examination. Preferably, the ferroelectric stack includes conductive metal oxide electrodes sandwiching the ferroelectric layer. In some embodiments, a higher ranked application is allocated more resources. An additional aspect of this method is terminating the flow of the first precursor andor the flow of the purge gas based on the monitored parameter of the quantity of the first precursor andor the purge gas. , Crystallization and stabilization of said melt with the aid of said scraped surface heat exchanger, Optionally, extrusion of the thus chilled mixture in block shape.