U.N. Secretary-General Kofi Annan held separate meetings with Israeli and Palestinian leaders today to try to stanch two weeks of bloodshed. The U.N. chief, leading world efforts to halt violence that has killed 90, all but five of them Palestinians or Israeli Arabs, met Israeli Prime Minister Ehud Barak before heading to Gaza to see Palestinian President Yasser Arafat. According to the U.N. Children’s Fund — that’s UNICEF — 22 children under the age of 18 have been killed, more than 1,000 wounded, in the violence.