Present perfect participle Vs. present participle

[KorawatT384]

Dear GMAT instructors,

I have a question about the usage of present perfect participle ie. having + V3 as a modifier. Is it ever correct to use this type of modifier on GMAT. I have done hundreds of problems and have never seen a single correct answer that uses present perfect participle. Have you ever seen any correct answer that uses present perfect participle? If so, could you please post a link to that. If not, could you explain the correct usage of this particular modifier? What tense should be used in the main clause if we were to use this kind of modifier?


In these two sentences, which one is correct?
Having created experiments, scientists showed that blah blah.
Vs.
Creating experiments, scientists showed that blah blah.

Thank you

[RonPurewal]

some-patients-who-do-not-respond-t4380.html

also, there's problem 51 in the SC chapter of the 2016 OG (sentence starts with "Neuroscientists..." -- we can't reproduce OG problems here)