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Summary of $ \alpha $ threshold values

For the system to be able to sustain $ k$ switch elements "on" at the same time, the condition $ \alpha<1/k^2$ must be met (for $ \sigma \gg 1$, this condition is also sufficient). Thus, for $ \alpha>1/4$, only 1 switch element can be on at a time. The corresponding equilibrium value is a decreasing function of $ \alpha $. For $ \alpha>\frac{\sigma^{2}}{4\left(n\sigma +1 \right)}$, there is an "extinction domain" around the diagonal $ x_1=..=x_n$: matching sufficiently closely the concentrations of the switch elements, at whatever value, makes the system switch off all switch elements. For large $ \sigma $, the extent of this domain is small, except in a very narrow range of $ \alpha $ values. Finally, for $ \alpha>\frac{\sigma^2}{4\left( \sigma +1 \right)}$, a condition which becomes $ \alpha > \sigma/4$ for large $ \sigma $, there are no non-0 steady states.