Both examples can be simply expressed in two separate reifications each. The first example contains two separate statements, one believed by Jane, the other believed by John. Using reification (in Turtle syntax) to express this would yield something like this:
:John :believes [ a rdf:Statement;
rdf:subject :earth ;
rdf:predicate :shape ;
rdf:object :round ] .
:Jane :believes [ a rdf:Statement;
rdf:subject :earth ;
rdf:predicate :shape ;
rdf:object :flat ] .
The second sentence can be expressed in a similar way, as two separate reifications. Marconi believes one thing, Bose believes something else.