As an expert on the science of sleep and sleep disorders, Michael Twery believes “People have good understanding about the necessity of sleeping 7-8 hours in bed. But they undervalue the function of napping in day.”

    For example, many Americans do nap. But one-third of adults in the US are also frequently tired. Someone who naps as a way of paying off a sleep debt may not experience the same improvements from napping as a healthy, well-rested person would.

    Also, many people may not want to admit that they take a nap. That only children, the very old, sick or lazy people nap is a common opinion. In fact, Americans sometimes do very strange things. For those who claim they only sleep five hours a night, they may think they are somehow stronger than the average human—superhuman, if you will.

    Luckily, many offices now offer napping rooms in many U. S. cities. While resting in the middle of the work day may seem like a luxury to Americans, napping is very much part of a normal, everyday life in other parts of the world.

China, generally speaking, is a land of nappers. Researchers recently looked at information provided by nearly 3, 000 Chinese adults, aged 65 years or older. Based on their answers, researchers put them into four groups: non-nappers (0 minutes), short nappers (less than 30 minutes), moderate nappers (30-90minutes), and extended nappers (more than 90 minutes).

    The study found that the hour-long nappers did better on the tests than those who napped for shorter and longer periods. Keep in mind, however, that these are the findings for those over the age of 65.

    Michael Twery notes that an hour long nap may be too long for young, healthy adults. “Currently, 30 minutes is enough to remove the pressure to sleep and will help us feel more awake. If we nap longer, we will get trapped into sleep inertia—a very deep sleep period.”

    Having a smart phone may not be as smart as you think. They may let you surf the Internet, listen to music and take photos wherever you are…but they also turn you into a workaholic（工作狂）,it seems.

    A study suggests that, by giving you access to emails at all times, the smart phone adds as much as two hours to your working day. Experts found that British people work an additional 460 hours a year on average as they are able to respond to emails on their mobiles. The study shows the average UK working day is between 9 and 10 hours, but 2 more hours is spent responding to or sending work emails, or making work calls.

    Almost one in ten admits spending up to three hours outside their normal working day checking work emails. Some workers say they are on call almost 24 hours a day. Nearly two-thirds say they often check work emails just before they go to bed and as soon as they wake up, while over a third have replied to one in the middle of the night. The average time for first checking emails is between 6 a.m and 7 a.m, with more than a third checking their first email in the period, and a quarter checking them between 11 p.m.and midnight.

    Ghadi Hobeika, marketing director of Pixmania, said: “The ability to access millions of Apps has made smart phone invaluable for many people. However, there are disadvantages. Many companies expect their employees to be on call 24 hours a day, seven days a week, and smart phones mean that people cannot get away from work. The more frequently in contact we become, the more is expected of us in a work capacity.”

    A sunflower is a sunflower. A mobile phone is a mobile phone. But can you combine the two to do something for your local environment? As early as next year it may well be possible. When you have finished with your mobile phone you will be able to bury it in a garden or a plant pot and wait for it to flower.

    A biodegradable (生物所能分解的) mobile phone was, this month, introduced by scientists. It is hoped that the new type of phone will encourage consumers to recycle.

    Scientists have come up with a new material over the last five years. It looks like any other plastic and can be hard or soft, and is able to change shape. Over time it can also break down into the soil without giving out any poisonous chemicals. British researchers used the new material to develop a phone cover that contains a sunflower seed. When this new type of cover turns into waste, it forms fertilizers. These feed the seed and help the flower grow.

    Engineers have designed a small transparent (透明的) window to hold the seed. They have made sure it only grows when the phone is throw n away. “We've only put sunflower seeds into the covers so far. But we are working with plant experts to find out which flowers would perform best. Maybe we could put roses in next time.” said one scientist.

    As phone technology is developing so quickly, people are constantly throwing their mobiles away. This means manufacturers are under pressure to find ways of recycling them. Some 650 million mobile phones have been sold this year. Most of them will be throw n away within two years, adding plastic, heavy metal and chemical waste to the environment. A biodegradable cover can offer some relief for nature, according to the scientists.

    “The seed comes out and the flower grows in the pot so you don't have to concern yourself with the phone when you have finished using it,” said Kerry Kirwan. She leads the research team, which is based at the University of Warwick in Britain.

    A killer whale(虎鲸) that can copy words such as “hello” and “bye-bye” is thought to be the first of its kind to copy human speech.

    The female killer whale learned to “speak” some human words by copying a trainer at a park in France. The animal's ability includes speaking the name “Amy” and “one, two, three”.

    Whales and dolphins are among the few animals except humans that can learn to produce a sound just by hearing it. “It is not often seen,” said Dr Josep Call, a co-researcher on the study. “Humans are good at it…Interestingly, the animals that can do best are marine mammals(海洋哺乳动物).” The researchers start to find out whether killer whales could learn new words by copying others. They studied a female named Wikie at Marineland Aquarium in Antibes, France. She was taught to speak human words.

    Dr Jose Abramson, a co-researcher on the study, said basic “conversations” with Wikie may one day be possible. He said,” It has been done before with a famous grey parrot and dolphins using American sign language(手势语).” However, he said they have to be careful about introducing human ideas on animals, as there is more to learn by trying to understand the natural way each kind communicates in its own environment. Wikie made sounds in water, which may be quite different.

    Dr Alex Thornton, senior speaker at the University of Exeter, said they still don't fully understand why some animals learn to copy. Some animals copy sounds to attract possible partners, while others copy sounds to become a member of a group. “Some whales, for example, learn their calls from one another to mark them out as members of their social group,” said Dr Thornton, who doesn't join in the research.

Learning New Vocabulary during Deep Sleep

    Sleeping time is sometimes considered unproductive time. This raises the question whether the time spent asleep could be used more productively, e.g. for learning a new language? Up-to-now sleep research focused on the stabilization and strengthening of memories that had been formed during wakefulness. However, learning during sleep has rarely been examined. There is enough evidence for wake-learned information undergoing a revision by replay in the sleeping brain. The replay during sleep strengthens the still weak memory and leaves the newly acquired information in the pre-existing store of knowledge.

    If re-play during sleep improves the storage of wake-learned information, then first-play, i.e. the initial processing of new information, should also be possible during sleep.

    The research group of Katharina Henke examined whether a sleeping person is able to form new semantic（语义的）associations between played foreign words and translation words during the brain cells' active states, the so-called "Up-states." It turned out to be that what they thought was reasonable. When we reach deep sleep stages, our brain cells progressively coordinate their activity. During deep sleep, the brain cells are commonly active for a brief period of time before they jointly enter into a state of brief inactivity. The active state is called "Up-state" and the inactive state "Down-state". The two states alternate（交替）about every half-second.

    New evidence for sleep-learning challenges current theories of sleep and theories of memory. The concept of sleep that we are separated from the physical environment is no longer reasonable. "It's false that complex learning be impossible during deep sleep," says Simon Ruch, co-first-author. "In how far and with what consequences deep sleep can be applied for the acquisition of new information will be a topic of research in upcoming years," says Katharina Henke.

    The research group of Katharina Henke is part of the Interfaculty Research Cooperation (IRC). Thirteen research groups in medicine, biology and psychology are part of the IRC. The aim of these research groups is to gain a better understanding of the mechanisms（原理）involved in sleep and consciousness.

On a chilly autumn morning in the Italian countryside near Larderello, Tuscany, the misty landscape reminded me why the area is nicknamed the Devil's Valley. The land here is a web of natural cracks in the rock that let a mix of steam and gases reach the surface.

Unlike the rolling hills and cypress-lined roads of other parts of Tuscany, the landscape here is covered with dozens of grey cooling towers puffing white vapors. The deafening roar of a turbine (涡轮机) at the Valle Secolo geothermal (地热的) plant breaks the quietness, but its violent spinning transforms steam rising from underground into energy for 150,000 families in the region. About 30% of Tuscany's electricity comes from this energy source. After producing electricity, the leftover steam heats water for nearby districts.

This underground energy has recently proved a vital resource. Italy greatly depended on Russian fossil fuels and in 2023 Italians bore the world's highest household electricity bills. Factories cut down production and households had to turn down their heaters. But residents of the Larderello area spent the winter in warm homes, thanks to the local geothermal plants working 24/7.

Bruno Della Vedova, president of the Italian Geothermal Union, hopes that in the future other Italian regions could benefit from such a resource, which is extremely important when the whole world looks to transition to renewable energy.

While countries like Iceland and Kenya are taking advantage of their geothermal resources, the industry's growth has made slow progress in Italy. High set-up costs and difficulties in extraction present significant barriers. And new plants often run into opposition from nearby communities over health concerns.

Italy sits on a geothermal sweet spot. Especially below Larderello, as Della Vedova says. A vast reservoir (储备) of steam and water is trapped between Earth's inner heat and a layer of clay-heavy rocks. High temperatures lead to the formation of steam directly inside the reservoir, providing a significant source of energy.

But while heat from Earth's core is practically endless, the water it heats within the planet are not. So Della Vedova says restoring underground water supplies and using them sustainably is critical for the future. "We can't take advantage of a geothermal resource at will," he says.