Washington and Boston, for instance, have employed sensors to detect the presence of biochemical agents in their subway systems.

The presence of deteriorating agents is a problem which can be tempered by selecting archival quality materials, such as acid free paper.

"We already know that the presence of agents doesn't slow you down," he said, kissing her.

The governor alone can sentence a person to death and all capital publishments to take place in the presence of accredited agents of the government.

The presence of strong oxidising agents or formaldehyde can cause false positives.

This reaction can be inhibited in the presence of antioxidant agents.

But American weapons experts have been collecting samples among the debris to test for the presence of dangerous chemicals or biological agents.

By all indications the various enigmatic events on Earth could only be accounted for by the presence of foreign agents.

An overriding long-term objective to avoid completely the presence of zoonotic agents in the feed and food chain is unrealistic.

If proved, the presence of Iranian agents inside Iraq would be potentially explosive here.