The Cleveland Clinic says the cause of cluster headaches is in a brain area known as a trigeminal-autonomic reflex pathway.

VOA: special.2010.03.30

Cadmium is a known carcinogen and is similar to lead in that it can hinder brain development in the very young.

VOA: standard.2010.01.11

"When our government has information on a known extremist and that information is not shared and acted upon as it should have been and this extremist boards a plane with dangerous explosives that could cost nearly 300 lives, a systemic failure has occurred.

VOA: standard.2009.12.29

But a local group came to his aid. The Arlington Street People's Assistance Network is also known as A-SPAN.

VOA: special.2010.12.20

By the time he returned to England in October of eighteen thirty-six, he was already a well known geologist and naturalist.

VOA: special.2009.02.25

At U.C.L.A. the man known simply as "Coach" had a record of six hundred twenty wins and one hundred forty-seven losses.

VOA: special.2010.06.10

Many colleges and employers will accept what is known as a GED as the equivalent of a high school diploma.

VOA: special.2009.08.20

He often commented on the fact that he was best known for a part he played for only three years.

VOA: special.2010.03.07

A medical aid program in Kenya offers hope to women and girls suffering from a condition known as fistula.

VOA: special.2010.08.09

And in some cases that might lead to more job interviews than a degree from a lesser known college.

VOA: special.2009.12.03

The chemicals are joining twelve other substances that are already banned under a treaty known as the Stockholm Convention.

VOA: special.2009.06.23

Many students save money by starting their education at a two-year public college, also known as a community college.

VOA: special.2010.04.08

A force known as the Army of the West used the Santa Fe Trail to protect American traders.

VOA: special.2009.03.30

A well-known example was when women's education groups objected to a talking Barbie that declared, among other things, "Math class is tough!"

VOA: special.2009.04.06