Some economists think the plan needs to provide as much as one trillion dollars or more to be effective.

VOA: special.2009.01.09

He says the study shows that, in theory,white roofs could be effective in reducing urban heat.

VOA: special.2010.03.02

But recent findings suggested that tPA may be effective in saving brain tissue even if three to four and a half hours have passed.

VOA: special.2009.09.22

But recent findings have suggested that tPA may be effective in saving brain tissue even if three to four and a half hours have passed.

VOA: special.2009.08.12

Farmers may think trees will take too long to grow and be effective.

VOA: special.2009.09.08

He believes the treatment could also be effective in human beings.

VOA: special.2010.03.16

So they can often be effective instruments of public diplomacy.

VOA: special.2010.06.21

Republicans on the financial services committee, including Representative Scott Garrett, voiced concerns that greater regulation may not be effective.

VOA: standard.2009.03.26

French says that, in addition to identifying how tele-rehabilitation could be effective, the experiment revealed limitations in the use of technology.

VOA: standard.2010.06.14

I expect a robust agreement at Copenhagen summit meeting that will be effective immediately and include specific recommendations on mitigation,adaptation, finance and technology.

VOA: standard.2009.12.09

Above all they need the political will behind them. And then they can be effective."

VOA: standard.2009.11.17

"They can work, they can be effective. They need to be adequately resourced.

VOA: standard.2009.11.17

Dr.Lepora says she will probably return to MSF, because she says once she learned how to be effective in a crisis situation, she finds it very difficult not to act when another crisis comes up.

VOA: standard.2010.06.29

Carol Pandak says tests found the new vaccine to be thirty percent more effective than the trivalent vaccine.

VOA: special.2010.01.18