1 . The body gives off many gases. Although some smells may signal a need to bathe or that you ate a certain meal, other gases might point to serious disease. Now, researchers have come up with a system that uses earmuffs to catch the disease-signaling gases. Doctors could get the information as patients wear a set of earmuffs. Results could be ready within minutes.

“The ear is a good place to monitor,” explains Johnson, a biomedical engineer. The ear’s skin is fairly thin, he notes. So gases don’t have to travel far to get out of the blood and escape through skin pores.

To collect the gases, Johnson and his team selected earmuffs that make a tight seal with the head. These are the type people often wear to protect the ears from loud noise. His team made two holes in the muff covering one ear. A tube slowly pumped air in one hole. Another tube pulled air out of the second hole and sent it to a sensor.

In their tests, the team found that they could measure changes in the amount of alcohol coming from the skin of the ear. It could work much like a Breathalyzer that police use to test people for driving drunk. The team invited three men. Each had to avoid drinking alcohol for at least three days before taking part. Once in the lab, these men wore the earmuffs and sat for 10 minutes as the system recorded normal gas levels leaving their ears. Afterward, the men drank a big amount of alcohol. About 7 minutes later, the earmuff system tested out a rise in alcohol leaving the skin. After 50 minutes, alcohol levels reached the peak and continued falling until the test was over.

The team then measured other gases by changing out the sensor. With the right sensor, their earmuff system could test out disease. Later, they replaced the earmuffs with a one-eared version to make it a bit more comfortable.

Johnson imagines another possible benefit. The earmuff system could help doctors tell whether a child’s ear infections have been caused by bacteria or a virus. How? Each type of infection exudes different gases. That, in turn, could guide how doctors cure the disease.

1. What makes the ear a good place to monitor?

A．Its small size.	B．Its thin skin.
C．Its clean surface.	D．Its blood flow.

2. What did Johnson and his team find in their tests?

A．Sensors should be examined in time.	B．Drunk-driving tests were ineffective.
C．Serious diseases were difficult to identify.	D．Their system could be used to tell diseases.

3. What does the underlined word “exudes” in Paragraph 6 most probably mean?

A．Collects.

B．Gives off.

C．Cuts off.

D．Uses.

4. In which section of a magazine is this passage most likely to appear?

A．Politics.

B．Business.

C．Science.

D．Entertainment.