The phrase "a single case where" is correct and usable in written English.
It can be used to refer to one specific instance or example of something occurring or being true.
Example: "There is a single case where the experiment yielded unexpected results, leading to further investigation."
Alternatives: "one instance in which" or "a solitary example of".
Feinstein said its investigators had not found a single case where that was true.
I do not know of a single case where a self-proclaimed feminist has physically castrated a man.
In my years in the agency, I cannot recall a single case where anyone was fired for failing to perform.
We don't have a single case where we have a businessman in jail for price fixing or monopoly practices.
Mr. Wall said his adversaries "can't point to a single case" where that had been a problem.
There wasn't a single case where coins were flipped about 7000 times and we got fewer than 3322 or more than 3636 heads or tails!
It is to be noted that § 9, which is complete in itself, makes no provision, in terms, for review of a certification by the Board and authorizes no use of the certification or of the record in a certification proceeding, except in the single case where there is a petition for enforcement or review of an order restraining an unfair labor practice as authorized by § 10(c).
However, in the single case where a sample was taken obliquely in a patient treated with ACI and mosaicplasty combined, this showed complete integration across all regions of the sample (see Fig. 1).
"It is absolutely classic -- we've seen this in every single case where a woman has stepped forward and made an allegation and gotten any kind of notoriety," said Susan Barnes, a lawyer who has represented military women who have brought sexual harassment cases.
Hence, the only scenario in which condition 2 potentially threatens Qualitative Stability in GRNs is a 'daisy chain' of linked 2-node feedback loops; in the single case where such a daisy chain is observed (in P. aeruginosa) both 2-node feedback loops are of the positive/negative type and so result in a form compatible with Qualitative Stability.
Therefore the only scenario in which condition 2) potentially threatens Qualitative Stability in GRNs is a 'daisy chain' of linked 2-node feedback loops; in the single case where such a daisy chain is observed (in P. aeruginosa) both 2-node feedback loops are of the positive/negative type and so are compatible with Qualitative Stability.
