Imagine living and working deep in the ocean. For some people, this idea might sound a little frightening. Others are fascinated by the chance to experience a mysterious world that so few humans get to see firsthand. Aquarius Reef Base is an undersea laboratory (n. 实验室) and habitat (n. 栖息地) located about 4.5 miles (7.24 kilometers) off the coast of Key Largo, Florida. It sits in a sandy area near a coral reef, about 60 feet (18.29 meters) below the ocean\'s surface.

Aquarius is owned by the National Oceanic and Atmospheric Administration (NOAA) and is operated by Florida International University. Scientists live in the Aquarius for 10 to 14 days at a time. There, they have the chance to spend 8 hours a day in the ocean without having to return to the surface. Aquarius is equipped with a shower, a toilet, a microwave, a refrigerator, computers, and Internet connection. The vessel measures about 43 feet (13 meters) long and 9 (2.7 meters) feet wide. Since 1993, more than 115 missions have been completed on Aquarius!

One of the greatest benefits to scientists working in Aquarius (often known as \"aquanauts\") is that they do not need to surface regularly, the way scuba divers do. Decompression (n. 减压) sickness is always a risk to scuba divers. Also known as \"the bends,\" it is the result of the pressure (n. 压强) differences deep underwater and at the surface. Common symptoms are joint pain (n. 关节疼痛), rashes, headaches, and dizziness. In severe vases, it can result in death. Aquanauts do not need to surface after a dive. They just return to Aquarius, which is pressurized. At the end of a mission, the scientists spend about 17 hours undergoing decompression. The pressure in Aquarius is slowly reduced over that time, so that the scientists can return to the surface without any ill effects.

The goal of the undersea explorer who work and live in Aquarius are diverse. The one thing they have in common is the desire to learn about and protect the oceans. Aquarius\'s nearness to a coral reef (n. 珊瑚礁) offers scientists an up-close look at this amazing habitat. Coral reefs around the world are threatened by pollution (n. 污染), overfishing, and climate change (n. 气候变化). Scientists can perform experiments, record observations, and take samples that allow them to better understand the reefs and their role in underwater ecosystems (n. 生态系统). In addition, they can determine the ways that human can best protect the reefs and save them from more damage.

One example of research done on Aquarius involves looking at the effect of UV rays on coral. Coral produces a chemical that protects it from UV rays. This is similar to the way sunblock protects humans. A decrease in the ozone layer (n. 臭氧层), the result of pollution, is causing UV rays to become more intense. This means that a coral reef\'s natural protection is no longer as effective as it once was.

Going forward, Florida International University hopes to offer more educational opportunities via Aquarius. What better way to create enthusiasm and a sense of responsibility for the oceans than to allow students to closely observe what is at risk? Classes are already sometimes taught in real time from Aquarius. There are several observation windows, so a simple Internet connection can allow students the experience of watching the undersea activities around the lab.

问题:

1. What causes \"the bends\"?

2. Aquarius is currently located off the coast of __________. (填空题)

3. What kind of research can aquanauts do on the nearby coral reef?