Complex sentence: Eight top scientists have disappeared, after responding to advertisements that have been placed in newspapers, for top level scientists in different fields of research, all offering very attractive rates of pay, but with the precondition that all applicants to be married with no children.
Split into simpler sentences: Eight top scientists have disappeared after responding to advertisements that have been placed in newspapers for top level scientists in different fields of research. All of the advertisements are offering very attractive rates of pay but with the precondition that all applicants to be married with no children.