Alexander I. Shlyakhter (1951-2000), Russian physicist.
Alexander Shlyakhter studied for his PhD in Leningrad under Dr Yuri Petrov, a prominent reactor designer at Leningrad (now Petersburg) Nuclear Physics Institute in Gatchina. He was known in the physics world for his noting that the existence of the "natural" nuclear reactor at Oklo in Gabon gave evidence that the physical fine structure constant alpha has changed less than 10^-17 per year over the last billion years or so. This idea was picked up and improved upon by Freeman Dyson.
In 1989 he emigrated to the United States and joined Prof. Richard Wilson's group at Harvard University. There he worked on understanding the effects of the radiation "incidents" in the Ural mountains at the Techa River, Kystym and Mayak, on understanding the effects of Chernobyl, and on demonstration that in many fields (including physics) scientists routinely underestimate the uncertainties, and he discussed a procedure for taking this into account.
More information, including scientific papers, is at http://alexonline.info.