Hit Units for Nonlinear Cases

As shown in equations (14)-(16), it is a simple matter to write Y x) [and also S x) and M x)] in lethal hit form because in the purely linear case the relationship between these two variables is simply x = z/ki. Similarly, for the pure power law case qk,pm), we have kgX = z, whence Xz = vz/, and so we can write 

Previously, we showed from equation (19) that the initial slope of the mutant yield curve plotted against dose is nonzero if, and only if, there is a one-lesion component process in mutation induction (see Section 6.1). Equation (43) tells us that the initial slope of the mutant yield curve when plotted against lethal hits is nonzero if, and only if, the monophasic powers by which both killing and mutation increase are equal. 

the complexity of equation (31) is such that it becomes cumbersome to write explicitly F(z), z, and T (0) for cases involving biphasic killing or mutation induction. 

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