Before revision:  And it is constructive in the sense that solutions to one of the inequality systems determine state and parameter vectors where the underlying mass action systems -- under explicitly stated genericity conditions -- undergo a saddle-node bifurcation  .
After revision:  And it is constructive in the sense that solutions to one of the inequality systems determine state and parameter vectors where the underlying mass action systems -- under explicitly stated genericity conditions -- a saddle-node bifurcation .