On May 23, 1989, Stefania Follini came out from a cave at Carlsbad, New Mexico. She hadn't seen the sun for eighteen and a half weeks. Stefania was in a research program, and the scientists in the program were studying body rhythms. In this experiment Stefania had spent 130days in a cave, 30 feet in depth.

    During her time in the cave, Stefania had been completely alone except for two white mice. Her living place had been very comfortable, but there had been nothing to tell her the time. She'd had no clocks or watches, no television or radio. There had been no natural light and the temperature had always been kept at 21℃.

    The results were very interesting. Stefania had been in the cave for over four months, but she thought she had been there for only two. Her body clock had changed. She hadn't kept to a 24-hour day, she had stayed awake for 20～25 hours and then had slept for 10 hours. She had eaten fewer meals and had lost 171bs in weight as a result! She had also become rather depressed.

    How had she spent her time in the cave? As part of the experiment she'd done some physical and mental tests. She'd recorded her daily activities and the results of the tests on a computer. This computer had been specially programmed for the project. Whenever she was free, she'd played cards, read books and listened to music. She'd also learned French from tapes.

    The experiment showed that our body clocks are affected by light and temperature. For example， the pattern of day and night makes us wake up and go to sleep. However, people are affected in different ways. Some people wake up naturally at 5:00 a.m., but others don't start to wake up till 9:00 or 10:00 a.m. This affects the whole daily rhythm. As a result the early risers are at their best in the late morning. The late risers, on the other hand, are tired during the day and only come to life in the afternoon or evening!

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Murcia

    I have spent about 8 months living in Murcia and I feel that I should put it as number one on my list. On my return from exploring other cities, I always feel like I'm returning home when I set foot in Murcia. The city centre is full of life and energy and has an incredible atmosphere all year round. Although the accent takes you a little time to get used to at first, you will adjust to it. Murcia is also home to some gorgeous(壮丽的) beaches and amazing coastal views. So it really does have the best of both worlds!

Gibraltar

    I visited Gibraltar during the Easter holidays and I was totally surprised by the beauty of Gibraltar! From a short cable car riding up to the top of the rock you are met with splendid views over the coast and the adorable monkeys which curiously come to greet you on your arrival. Make sure to hide all your food because they think it's a gift for them!

Valencia

    Valencia is beautiful. It's as simple as that! The river-area is so exciting and full of life, all the way up to the science museum and beaches. However, I was a little confused by the fact that the river had long been filled in and turned into a park, yet people still referred to it as The River.

Alicante

    I have spent many a weekend in Alicante, making the most of the beautiful beach in low season, before all the tourists arrive. May is the high season here, so I'd definitely recommend a visit in April, September, or October, just before or after the holiday season.

    It's not easy being a teenager— nor is it easy being the parent of a teenager. You can make your child feel angry, hurt, or misunderstood by what you say without realizing it yourself. It is important to give your child the space he needs to grow while gently letting him know that you'll still be there for him when he needs you.

    Expect a lot from your child, just not everything. Except for health and safety problems, such as drug use or careless driving; consider everything else open to discussion. If your child is unwilling to discuss something, don't insist he tell you what's on his mind. The more you insist, the more likely that he'll clam up. Instead, let him attempt to solve things by himself. At the same time, remind him that you're always there for him if he seeks advice or help. Show respect for your teenager's privacy (隐私). Never read his mail or listen in on personal conversations.

    Teach your teenager that the family phone is for the whole family. If your child talks on the family's telephone for too long, tell him he can talk for 15 minutes, but then he must stay off the phone for at least an equal period of time. This not only frees up the line so that other family members can make and receive calls, but teaches your teenager moderation (节制). Or if you are open to the idea, allow your teenager his own phone that he pays for with his own pocket money or a part-time job.

    Claude Monet, Pablo Picasso and Leonardo da Vinci ... the art world has never lacked talent. And now, a new painter is ready to join the list although this one isn't even human.

    Next month, auction house Christie's Prints and Multiples will make history by offering the first piece of art created by artificial intelligence (AI) for sale. The painting is a portrait of a man called Edmond De Bela- my, and is expected to be sold for up to $10,000.

    The work, which features a man with a mysterious look on his face, was created by software developed by the French art group Obvious. Laugero-Lasserre, an art collector, called the work "grotesque and amazing at the same time". This isn't the first example of Al-produced artwork, as AI has already been used to write poems and compose .songs. However, many people doubt whether it should be called art at all.

According to Russian writer Leo Tolstroy (1828 -1910), art is about creating emotion (情感). It's "a means of …joining people together in the same feelings' he once said.

So, if the emotion behind art is what makes it, the ability to create and use tools is what makes human Icings different from other species. And as a tool itself, the AI technology used to create the portrait is the result of a lot of effort made by several designers. Together, they "fed" the AI a huge collection of paintings from the 14th to the 18th centuries, until it was able to work out how to make similar paintings of its own.

    The introduction of AI art could be the beginning of a new artistic movement. However, not everyone is ready to welcome these high-tech artists just yet.

    "The human mind is what's behind the AI technology. And the human mind is not a cold, hard fact," said Oscar Schwartz, a professor of AI. "Rather, it in something that's created with our opinions and something that changes over

    I began cycling in 2004 when I was a poor student. It was dangerous, sure, but cycling is the fastest, cheapest point-to-point form of transport in Melbourne. I own a car now, but that's just for transporting the baby or groceries.

    I hate driving. So it's been quite encouraging watching the growth in cyclist numbers over the past decade. It is said that over 10,000 cyclists enter the CBD (Central Business District) each day, taking pressure off public transport. But as more people take to cycling as a way of transport, the number of cyclists seriously injured or killed keeps increasing. And that is a sign that our infrastructure (基础设施) is still not good enough.

    Melbourne was once a dream for cyclists—flat, long, wide roads, with plenty of paths along rivers. Now, cycling can be deadly, with roads taken up by cars. I have a friend who broke her back and was lucky to escape death and others with broken bones. In my time riding, I've been forced off the road by a truck, cut off by four-wheel drives, and told to get off the road. Drivers are a particularly rude to cyclists. And that's a sign of exactly one thing: inadequate infrastructure.

    We shouldn't need to be taught how to coexist in the same narrow space. Drivers and cyclists should be kept apart. Designing bike paths so riders are channelled between moving cars and parked cars is deadly. All it takes is one daydreaming driver to fling open the door and you are gone. That's what happened to the young university student James.

    This year, there are to be new cycling lanes (车道) built on Glen Road, where James died in 2010. But these lanes are not safe. Cyclists must still pass between two rows of cars.

    Compared with solar and wind energy, which are booming, tidal (潮汐的) power is a loser in the clean - energy competition. But if you did want to build a tidal power station, there are few better sites than the mouth of the River Severn, in Britain. Its tidal range, the difference in depth between high and low tides, of around 15 metres is among the largest in the world.

    Engineers and governments have been toying with the idea since at least 1925. But none of the suggested projects has materialised. Price is one objection. A study thought that tidal energy might cost between ￡216 and ￡368 ($306 - 521) per MWh of electricity by 2025, compared with ￡58 - 75 for seagoing wind turbines (轮机) and ￡55 - 76 for solar panels. Environmentalists also worry that any plant would change the tides, making life harder for wildlife.

    An engineer called Rod Rainey thinks he has a way around both problems. He plans to replace the conventional turbines of previous plans with a much older technology. Specifically, he plans to span (横跨) the river mouth with a line of water wheels. This is a design that dates back to the early days of the Industrial Revolution. Examples can be found fixed to the sides of old watermills (水磨).

    But there would be nothing old - fashioned about Mr Rainey's wheels. Thirty metres high and sixty wide, they would be made from ordinary steel. Two hundred and fifty of them, along with the supporting structures, would be floated into place and secured to the seabed, creating a line 15km long. Together, they could supply power at an avenge ate of 4GW. That is about as much as two biggish nuclear power stations would manage. Substituting one of the wheels with a set of locks would provide a shipping channel about twice the width of Panama Canal, permitting upstream ports such as Avonmouth and Cardiff to continue operating.