Oyster

What is an Oyster card?

    Oyster is the easiest way to pay for journeys on the bus, Tube, tram, DocklandsLight Railway (DLR), London Overground and National Rail journeys in London Youcan store your travel cards, Bus & Tram Pass, season tickets and credit topay for journeys as you go.

Where to get an Oyster card?

There are a number of ways for you to get an Oyster card:

• At over 3,900 Oyster Ticket stops

• At Tube and London Overground station ticket offices

• At some National Rail stations

• At London Travel information Centres

• Online at tfl. gov. uk/oyster

How to use an Oyster card?

    To pay the correct fare on the Tube , DLR, London Overground andNational Rail services, you must always touch in on the yellow Oyster cardreader at the start of your journey, and touch out at the end. If you don't, amaximum cash Oyster fare will be charged. When using the bus or tram, you mustonly touch in at the start, but not at the end of your journey.

   What happens if I don't visit London very often?

    Don't worry. Any pay as you go credit on your card will notexpire (过期), so you cankeep it for your next visit or lend it to a friend.

Fares

Traveling by Tube from Central London (Zone l)to Heathrow (Zone6)

Adult Oyster single fare

£ 4. 20 Monday to Friday 06:30 - 09:30 and 16:00 - 19:00

£ 2. 70 at all other times including public holidays

Adult single cash fare £ 5.00

For further information，visit tfl.gov.uk /fares.

    Apple is to open a research lab in the southern Chinese city of Shenzhen, according to Tim Cook, its chief executive, as it seeks to boost sales in the country and improve ties with the authorities.

    Beijing has been encouraging foreign technology companies to carry out more high-end work on the mainland as part of efforts to revitalize local industry.

    It will be Apple's second facility in China. It already has a new research and development facility in Beijing.

    The two R&D centers were “aimed at strengthening relationships with local partners and universities as we work to support talent development across the country”, Apple said in a statement.

    A closer relationship with the Chinese authorities has been a priority following setbacks for the US technology company this year.

    The iPhone has been losing market share to high-end handsets made by local competitors including Huawei, Vivo and Oppo, which topped the rankings in the second quarter, while Apple languished in fifth place, according to Canalys data.

    Analysts said the announcement of the R&D centre was Mr. Cook's latest attempt to gain favour with Beijing, following the US group's $1billion investment in Didi Chuxing, the Chinese car-hailing company, in May.

    Apple has had to change its approach in China as it faces rising nationalism and high-quality local competition, according to Ge Jia, a tech blogger, who wrote yesterday: “It's time for Apple to cast aside their pride.” “Their previous strategy of only selling devices to China without leaving anything behind is not working any more and they are starting their process of localisation in China through the Shenzhen lab.”

    Most people know precious gemstones (宝石) by their appearances. An emerald flashes deep green, a ruby seems to hold a red fire inside, and a diamond shines like a star. It's more difficult to tell where the gem was mined, since a diamond from Australia or Arkansas may appear the same to one from the Democratic Republic of the Congo. However, recently, a team of scientists has found a way to identify a gemstone's origin.

    Beneath the surface of a gemstone, on the tiny level of atoms and molecules（分子）, lie clues (线索) to its origin. At this year's meeting of the Geological Society of America in Minneapolis, Catherine McManus reported on a technique that uses lasers (激光) to clarify these clues and identify a stone's homeland. McManus directs scientific research at Materialytics, in Killeen, Texas. The company is developing the technique. “With enough data, we could identify which country, which mining place, even the individual mine a gemstone comes from,” McManus told Science News.

    Some gemstones, including many diamonds, come from war-torn countries. Sales of those “blood minerals” may encourage violent civil wars where innocent people are injured or killed. In an effort to reduce the trade in blood minerals, the U.S. government passed law in July 2010 that requires companies that sell gemstones to determine the origins of their stones.

    To figure out where gemstones come from, McManus and her team focus a powerful laser on a small sample of the gemstone. The technique is called laser-induced breakdown spectroscopy. Just as heat can turn ice into water or water into steam, energy from the laser changes the state of matter of the stone. The laser changes a miniscule part of the gemstone into plasma, a gas state of matter in which tiny particles（微粒）called electrons separate from atoms.

    The plasma, which is superhot, produces a light pattern. (The science of analyzing this kind of light pattern is called spectroscopy.) Different elements produce different patterns, but McManus and her team say that gemstones from the same area produce similar patterns. Materialytics has already collected patterns from thousands of gemstones, including more than 200 from diamonds. They can compare the light pattern from an unknown gemstone to patterns they do know and look for a match. The light pattern acts like a signature, telling the researchers the origin of the gemstone.

    In a small test, the laser technique correctly identified the origins of 95 out of every 100 diamonds. For gemstones like emeralds and rubies, the technique proved successful for 98 out of every 100 stones. The scientists need to collect and analyze more samples, including those from war-torn countries, before the tool is ready for commercial use.

    Scientists like Barbara Dutrow, a mineralogist from Louisiana State University in Baton Rouge, find the technique exciting. “This is a basic new tool that could provide a better fingerprint of a material from a particular locality,” she told Science News.

    Most people looking for ways to quit smoking worry about weight gain, and with good reason. Smokers who quit tend to pack on an average of 5 pounds after they stop smoking cigarettes. A new study, published by the journal Science, explains why this happens.

    The new research explains that nicotine appears to combine with appetite-regulating neurons (调节食欲的神经元) in the brain, besides the receptors (感受器) that bring about addiction. These neurons help regulate how much food gets consumed, but under the influence of nicotine, they lose their self-control. This is why when smokers quit, they tend to eat more and gain weight.

    The researchers believe that their discovery will lead to the development of drugs that aim at nicotine receptors on brain cells that control appetite. In the future, weight gain may no longer be a reason for smokers to delay the decision to kick the habit, but that's no reason to wait. Nicotine-replacement treatment, while not for everyone, can help. Here are a few more ways to quit smoking and stay slim.

    Drink water. To improve metabolic (新陈代谢的) rates, make half of those glasses ice water. Juice can be too high in calories, something you'll want to keep an eye on your journey toward being a slimmer non-smoker. Plan your snacks. Healthy snacks help keep your metabolism working, so you continue to burn calories while stopping wild hunger pain, or fake hunger.

    Keep moving. Exercise kills two birds with one stone. It helps you burn calories and prevents you from eating when you're not truly hungry. It's also a feel-good stress reliever (缓解物). Focus on your fitness and how being healthy makes you feel. Make exercise a goal and think of quitting as your reward for being physically fit.

Robots have long been drawing inspiration from animals, with the creation of robot dogs or snake-shaped robots. And yet, the field of robotics is far less enthusiastic about the other kind of living things—plants. Barbara Mazzolai, an Italian roboticist owes this to a misconception about plant behavior: that they cannot move or think. "It's not true at all," she says. To challenge this view, Dr Mazzolai and her team recently launched a machine called "FiloBot", a robot based on a climbing species.

To survive, a climbing plant must switch between several different behaviors. In forest environments, it must first grow out of the soil and travel along the ground in search of a support to hold onto, such as a nearby tree. Once a support is located, though, the plant fixes itself around the object and then growing towards the light. To choose the best angle to grow upwards, a climbing plant uses its shoots(芽) to receive information about light and gravity.

FiloBot has sensors on its main shoot. It can 3D-print its body with plastic and grow at a controllable rate. These functions researchers found, enabled FiloBot to cross gaps, and find things to attach to. The lack of heavy on-board computing device means that it is light and requires minimal care, while its slow pace means that it doesn't disturb things around it, making it possible to move through a complex, unseen environment, or monitoring disaster sites.

For now, FiloBot is still being tested. Its tendrils(卷须) have not left the laboratory. Still, it has already been employed in deconstructing plant behaviour. For example, it was long assumed that climbing plants find their supports by growing towards shade, though the exact mechanism was unclear. FiloBot could imitate this behaviour by detecting far-red light, which is typical of shaded areas, providing clues to how plants do it.

Dr Mazzolai hopes that such projects will inspire other roboticists to take their cues from plants and develop completely new technologies.

China has set new rules limiting the amount of time children can play online games. The rules limit children to just three hours of online game playing a week. That is one hour between 8 p. m. and 9 p. m. on Friday, Saturday and Sunday most weeks. 

Li Zhanguo has two children aged 4 and 8. Even though they do not have smartphones, they enjoy playing online games. Like many other parents. Li is happy with new government rules. But experts say it is unclear if such policies can help prevent addiction to online games. Children might just get addicted to social media instead. In the end, experts say, parents should be the ones to set limits and support good practice. 

There has been a growing concern in China about gaming addiction among children. Government reports in 2018 found that about one in ten Chinese children were addicted to the Internet. The new rules are part of an effort to prevent young people from spending too much time on unhealthy entertainment. That includes what officials call the "irrational fan culture" 

Under the new rules, the responsibility for making sure children play only three hours a day as largely on Chinese gaming companies like Net Ease and Ten cent. Companies have set up real-name registration systems to prevent young users from going past game time limits. They have used facial recognition technology to check their identities. And they have also set up a program that permits people to report what is against the law. It is unclear what punishments gaming companies may face if they do not carry out the policies. And even if such policies are performed, it is also unclear whether they can prevent online addiction. 

A specialist treating Internet addiction expects about 20 percent of children will find ways to break the rules by borrowing accounts of their older relatives and find a way around facial recognition. In his opinion, short-video alps such as Douyin and Kuaishou are also very popular in China. They are not under the same restrictions as games.