A common type of metastability is isomerism. Any discussion of sonoluminescence must include a detailed analysis of metastability. Care must be taken when building clock domain crossing circuitry to avoid metastability. Clocked sequential systems are one way to solve metastability problems. A common example of metastability in science is isomerisation. SDS resistance is based on a metastability of the protein fold. Here, the term metastability is used rather loosely. Kelso has worked on metastability in neuroscience. He can also be hyperpolarized using metastability exchange optical pumping (MEOP). Serious computer and digital hardware bugs caused by metastability have a fascinating social history. Although in some models the NTS charge is bounded by the stability (or metastability) condition. A ball resting in a hollow on a slope is a simple example of metastability. Metastability is an instance of the paradox. This is because metastability is more than simply a matter of circuit design. For example, many serpins (serine protease inhibitors) show this metastability.