1.   A study at Duke University explored how fragrant aromas might sweeten the interpersonal atmosphere on New York City subways.

2.   Beijing frequently times such releases to sweeten the atmosphere for important meetings with high-level U.S. officials.

3.   But it has tried to sweeten the atmosphere, canceling a military display and visits abroad by its vice president that could have riled Beijing.

4.   He noted that to sweeten the atmosphere, Hayes promised not to run for a second term.