Officials had planned to execute its first prisoner by lethal injection last week, but another last-minute delay cast uncertainty on when that will actually happen.
But some batches of heparin containing the contaminant did not elicit adverse reactions, casting uncertainty on their root cause, Dr. Fareed said.
The withdrawal of the Turkish diplomats on Monday cast uncertainty on the fate of other imprisoned journalists, including four from the West who have been held by the Qaddafi government since early April.
Still, though fighting was reported to have died down by late afternoon in Basra, it continued in Baghdad, including heavy combat by Iraqi and American troops and aircraft in the Mahdi Army stronghold of Sadr City, casting uncertainty on the deal.
The release of the emails is a classic "merchants of doubt" tactic, stolen from the tobacco industry who realised that when the scientific case was unanswerable, casting uncertainty on it was a very effective way to block action.
In the Philadelphia suburb of Hilltown Township, which approved limits on cell phones, the law was struck down by a county judge only two days before passage of the Marlboro ordinance, casting uncertainty on the laws in several Pennsylvania towns and raising questions as to whether state motor vehicle laws preclude municipalities from enforcing the measures.
Omar's disappearance had cast uncertainty on the future of the Afghan peace process and even the Taliban itself.
The NYPD's call log shows no such call, casting uncertainty on both the Department and the neighbor's perhaps fictionalized, Brian Williamemorye memory.
During a short break early the next year, after touring Australia and New Zealand, drummer Carey suffered a biceps tear during a skirmish with his girlfriend's dog, casting uncertainty on the band's upcoming concerts in North America.
