The Tunisian Foreign Ministry announced that Libyan leader Colonel Moammar Al Kaddafy arrived in Tunis this morning, Monday, for a "brotherly and recreational" visit, at the invitation of Tunisian President Zine El Abidine Bin Ali.
Can we say the following?
Libya's leader Colonel Muammar Qaddafi arrived in Tunisia at the invitation of President Zine El Abidine Bin Ali.

yes

Stefano Falconi, director of finance at the Massachusetts Institute of Technology (MIT), has joined Carnegie Mellon as its vice president for administration and chief financial officer. Falconi succeeds Jeff Bolton, who left the university last July to become chief financial officer at the Mayo Foundation in Rochester, Minn.
Can we say the following?
The Massachusetts Institute of Technology (MIT) appoints Stefano Falconi as chief financial officer.

no

In the two weeks since his death, police have been posted outside the Beijing home where Mr. Zhao spent his last 15 years under house arrest and where hundreds have been assembling to pay tribute. Agents have been turning many of the mourners away.
Can we say the following?
Mr. Zhao died in Beijing.

yes

Washington Scientists have identified a hormone that significantly extends the lifespan of mice, a discovery that could mark a crucial step toward developing drugs that boost longevity in people.
Can we say the following?
Texas researchers have found a naturally occurring hormone that can extend the lifespan of mice by as much as 30%, a discovery that opens a new avenue of research into human longevity.
no