Their findings could help to engineer plants that grow better and more effectively in conditions with higher levels of carbon dioxide.

VOA: special.2010.01.26

The exploration vehicle will be able to measure methane even at very low levels in many places on the surface.

VOA: special.2009.12.30

The Justice Department says rates in recent years fell to levels last seen in the middle of the nineteen sixties.

VOA: special.2009.12.19

One-third of those asked said stress levels about their financial situation are much higher now than a year ago.

VOA: special.2010.10.12

The agreement sets targets to prevent the Earth's average temperature from rising more than two degrees Celsius above pre-industrial levels.

VOA: special.2009.12.26

If several of these conditions are present at the same time, a person's body temperature may rise above safe levels.

VOA: special.2010.07.27

Mister Schroeder says that carbon dioxide levels in the atmosphere are much higher now than they were in the past.

VOA: special.2010.01.26

A published report says the genetic changes could be linked to stress levels during this method of giving birth.

VOA: special.2009.11.24

The four levels of rooms center on a beautiful courtyard with a glass ceiling to let light shine in.

VOA: special.2009.01.11

All agreed that global temperatures should not rise by more than an average of two degrees Celsius above pre-industrial levels.

VOA: special.2009.07.11

He says they might be trying to increase their dopamine levels to make up for the deficits in their reward system.

VOA: special.2009.09.16

They found the highest levels of solar activity cause small, but far-reaching effects on weather systems around the world.

VOA: special.2009.09.29

Later,she raised money to help poor immigrant women who had been passengers on the lower levels of the Titanic.

VOA: special.2010.03.08

He says they might be attempting to increase their dopamine levels to make up for the deficits in their reward system.

VOA: special.2009.09.29