Before the laser, scientists developed a similar device: a maser which stands for Microwave Amplification by Stimulated Emission of Radiation.

VOA: special.2010.09.01

So for the ten patients in the study, doctors used a low amount of radiation to destroy only some of their marrow.

VOA: special.2009.12.16

They found that in many cases, the risk of developing cancer from the radiation outweighed the risk of a serious brain injury.

VOA: special.2009.10.28

Another was a set of special instruments that helped measure the effects of the sun's radiation on the outside of the aircraft.

VOA: special.2010.07.07

But a recent study warned that more children than necessary are being exposed to radiation this way.

VOA: special.2009.10.28

People can get cancer from low doses of ionizing radiation, the kind released in a nuclear accident.

VOA: special.2011.03.16

The patient does not get much radiation from the process, which lasts only a few minutes.

VOA: special.2010.08.31

The most important was the discovery of a belt of radiation around the Earth.

VOA: special.2009.06.10

Microwaves are a form of electromagnetic radiation similar to, but shorter than,radio waves.

VOA: special.2010.09.01

every year, the government is under pressure to make an official recommendation on how much radiation is safe during a CT scan.

VOA: standard.2010.04.07

In a real nuclear attack, hundreds of thousands of people would have to be decontaminated from radiation.

VOA: standard.2010.07.21

In two other cities, Los Angeles,California and Huntsville,Alabama, a study also showed significant differences in radiation.

VOA: standard.2010.01.30

But some doctors say the CT scan exposes patients unnecessarily to harmful radiation, as much radiation as a patient might receive from 400 chest x-rays.

VOA: standard.2010.04.07

Journal editor Catherine DeAngelis says another article describes the high success rate of tumor control for a new form of radiation for inoperable lung cancer.

VOA: standard.2010.03.25

It exposes a patient to much larger doses of radiation than the usual x-ray.

VOA: standard.2010.01.30

Experts say terrorist groups are seeking materials for a crude nuclear device - a so-called "dirty bomb" - that would have limited blast potential but could spread radiation in a major urban area.

VOA: standard.2010.04.11

The United Nations Environment Program said many inhabitants of towns in northeast Somalia suffered from diseases consistent with radiation sickness following a Tsunami in 2004, that may have stirred up tons of nuclear and toxic waste.

VOA: standard.2009.10.30

In mid-April,Kenya signed a deal, which will allow the United States to install radiation sensors and other equipment at its busy Mombasa seaport to detect any nuclear or radiological materials that could be smuggled in to be used in a weapon.

VOA: standard.2009.05.01