Rome — Doctors and medical groups around the world last weekend reacted with strong opposition to the news that an Italian specialist is on the brink of cloning the first human baby.

Dr. Severino Antinori, who is the head of a hospital in Rome, has been referred to in an Arab newspaper as claiming that one of his patients is eight weeks pregnant (怀孕) with a cloned baby.

Antinori refused to comment on the reports, but in March 2001 he said he hoped to produce a cloned embryo (卵) for implantation within two years. So far seven different kinds of mammals have already successfully cloned, including sheep, cats and most recently rabbits.

Doctors showed their doubt and were strongly opposed although they admit that human cloning would finally come true unless there was a world wide ban on the practice.

Professor Rudolf Jaenisch of the Whitehead Institute for Biomedical Research at the Massachusetts Institute of Technology: “I find it astonishing that people do this where the result can be foretold that it will not be a normal baby. It is using humans as guinea pigs. It makes people feel sick.”

But Ronald Green, director of the Ethics Institute at Darmouth College in the US, said it is unlikely that an eight-week-old pregnancy would lead to a birth.

So far all cloned animals have suffered from some different serious disorders, many of them dying soon after their births.

Doctors are opposed to human cloning because they are worried about the welfare of the cloned child if there is one.

“There are no benefits of cloned human beings, just harm,” said Dr .Michael Wilks of the UK.

NATIONAL GEOGRAPHIC NEWS

Warning from Experts

A growing amount of human- made orbital debris(太空轨道残骸)---from rocket stages and out-of-date satellites---- is circling the Earth. Scientists say the orbital debris, better known as space junk, poses an increasing threat to space activities. “This is a growing environmental problem,” said Nicholas Johnson, the chief scientist and program manager for orbital debris at NASA(美国航空航天局) in Houston, Texas.

Johnson and his team have developed a computer model capable of simulating past and future amounts of space junk. The model predicts that even without future rocket or satellite launches, the amount of debris in low orbit around Earth will steady through 2055, after which it will increase. While current efforts have focused on limiting future space junk, these scientists say removing large pieces of old space junk will soon be necessary.

Since the first launch of satellite in 1957, humans have been generating space junk. The U.S. Space Surveillance Network is currently tracking over 13,000 human-made objects larger than ten centimeters in diameter orbiting the Earth. “Of the 13,000 objects, over 40 percent came from breakups of both spacecraft and rocket bodies,” Johnson said. In addition, there are hundreds of thousands of smaller objects in space. These include everything from pieces of plastic to bits of paint. Much of this smaller junk has come from exploding rocket stages. Stages are sections of a rocket that have their own fuel or engines.

These objects travel at speeds over 35,000 kilometers an hour. At such high speed, even small junk can tear holes in a spacecraft or disable a satellite by causing electrical shorts that result from clouds of superheated gas.

Johnson believes it may be time to think about how to remove junk from space. Previous proposals range from sending up spacecrafts to grab junk and bring it down to using lasers to slow an objects orbit to cause it to fall back to Earth more quickly. Given current technology, those proposals appear neither technically nor economically practical, “Space junk is like any environmental problem,” Johnson admits. “It’s growing. If you don’t deal with it now, it will only become worse, and the solutions in the future are going to be even more costly.”

Daily life has its satisfactions. The perfect reply to a friend’s text message. The first after-work drink. The sound of another government U-turn. But do any really compare to the joy of going to sleep? That moment when all the mess disappears into the embrace of a mattress(床垫)?

Somehow we have pushed this pleasure to the back of the queue. A third of American adults report sleeping less than the recommended seven hours. Many of us feel a lack of rest.

Stressing ourselves out about a lack of sleep can make the problem worse. In his book Overcoming Insomnia and Sleep Problems, Oxford professor Colin Espie writes about “orthosomnia(完美睡眠症)”, where people are so focused with sleeping well that they become too anxious to do so. The marketing of sleeping aids adds to this.

Espie says we each have a sleep pattern that, like a shoe size, we figure out through trial and error. The research on bedtimes between 10pm and 11pm will cheer those who leave parties early and give up late-night football highlights, but it establishes no causal link. Genetically, some humans are larks(百灵鸟) and some are owls(猫头鹰); the larks may just have better cardiovascular(心血管) health. For an owl to try to fight their natural schedule, and sleep earlier, wouldn’t necessarily help.

Once we weren’t urged to sleep until we were dead. Now we are told to sleep or we’ll be dead. Taking our biology seriously suggests that Netflix should not try to compete with sleep, and the city that never sleeps is not as cool as it sounds. But nowadays sleep is becoming something that people try to excel at. About that I’m unconvinced. A good night’s sleep is a pleasure. As far as possible, it should also remain a simple one.