Before revision:  We then show that, if the input is persistent, then the positive part of the log-likelihood ratio can be approximately computed by using the continuous-time signals of the number of active TF molecules and the number of bound promoters  . Finally, we show how we can use a coherent feedforward loop  to approximately compute this log-likelihood ratio.
After revision:  We then show that, if the input is persistent, then the positive part of the log-likelihood ratio can be approximately computed by using the continuous-time signals of the number of active TF molecules and the number of bound promoters when the input is persistent . Finally, we show how we can use a coherent feedforward loop to approximately compute this log-likelihood ratio.