OK, here are screenshots for my two cities in question, Rostov and Saxon. Both are well past the WWII and just before the spaceship launch. The game is 1.7 mB so it's too large to post. Rostv was captured by the enemy twice and I reclaimed it twice. Saxon was captured once by the enemy and I recaptured it. No other cities showed extra scientists except the noprmal 2 from a research institute.
Extra buildings for each city not in screenshot
Rostov: Industrial park, Public trans, library, university, observatory, research institute, theater, broadcast tower, grocer, supermakter, courthouse, jail, levee
Saxon: factory, coal and hydro plants, indu. park, public trans, library, university, observatory, research inst., broadacast tower, bank, courthouse.
I do not have nmay other saves and I do not recall what building were lost after capture and which I had to rebuild. I am pretty sure the reaserch institutes surved all attacks.