Whenever we see a button, we are eager to press it because we know something will happen. This is true in most cases, for example on a doorbell and on the “on/off” button on the TV. But some buttons are actually fake, like the “close” button on a lift.

    Many people are in the habit of pressing the “close” button because they don't have the patience to wait for the lift doors to shut. But lifts' “close” buttons are a complete scam(骗局), at least in the US-the doors will not close any faster no matter how hard you press.

    It started in the 1990s when the Americans with Disabilities Act was passed in the US, making sure that all lifts stayed open long enough so that people with disabilities could enter. Only US firefighters and repairmen can use the buttons to speed up the door-closing process if they have a code or special keys.

    But to normal lift riders, the buttons aren't completely useless. According to psychologists, fake buttons can actually make you feel better by offering you a sense of control.

    “Perceived (能够感知的)control is very important. It reduces stress and increases well-being,” Ellen J. Langer, a psychology professor, said, “having a lack of control is associated with depression.”

    Experts have revealed that a lot of buttons that don't do anything exist in our lives for this same purpose. For example, many offices in the US have fake thermostats(温度调节器) because people tend to feel better when they think they can control the temperature in their workspace.

    But psychologists found it interesting that even when people are aware of these little “white lies”, they still continue to push fake buttons because as long as the doors eventually close, it is considered to be worth the effort.

    “That habit is here to stay,” John Kounios, a psychology professor, said“Even though I have real doubts about the traffic light buttons, I always press them. After all, I've got nothing else to do while waiting. So why not press the button in the hope that this one will work?”

    An American company has built a new drone（无人机）that could improve the speed of deliveries（送交的货）.

    The drone is very different from other unmanned aircraft.It is made almost completely out of cardboard and has no motor.It can be packed with materials and sealed up with tape.

    Because the drones do not have a motor,they are designed to be dropped from airplanes.Hundreds of drones could be sent out at once.Then they could be automatically guided to where they are supposed to go.The company says these drones could then complete deliveries to different places over an area covering hundreds of kilometers. The drones look bigger than the paper airplanes we used to make as kids.But this light flyer is not a toy.It is aerodynamically designed and equipped with a small computer,a battery and sensors to guide it to the ground.

    The drones are being developed by Otherlab—a technology research company in San Francisco,California.It calls the drone a "Sky Machine."

    The company says it can travel about 150 kilometers at speeds up to 88 kilometers an hour.Now,it can carry materials weighing up to one kilogram,but future models are expected to carry larger loads.

    One of the drone's main advantages is that it does not have a heavy motor or large battery.This allows more room for materials and makes the drone cost less to build and operate.

    The Otherlab development team has called its invention the "Ikea of drones".This is because it is packaged similarly to products from the Swedish furniture maker Ikea.The drone arrives as flat pieces of pre-cut cardboard that can be quickly and easily put together.

    The technology that guides the drone can make it land within 10 meters of its target,according to Otherlab. Unlike other drones,even a crash landing is acceptable.The company says the drones can also be reused.

    Once the drone completes its delivery,it can be thrown away and the cardboard material will likely break down within a few months.

    The company has received money from the U.S. Department of Defense to carry out research on the drones.The money came from the Defense Advanced Research Projects Agency.The agency is attempting to find the best delivery vehicles that can disappear after their missions are complete.The U.S. military has a need for delivery drones.But it wants to simplify and lower the cost of using them.Otherlab's Sky Machines are an attempt to fill that need.

    Military drones can also be stolen and studied by others if found after use.Before they can truly disappear,the electronic materials inside must also somehow disappear.Researchers are still working on ways to get the technology itself to self-destruct.

    What do you use to unlock your cellphone? A password? A fingerprint? Or simply a glance?

    On September 12, 2017, Apple introduced its iPhone X, which has an eye-catching feature—Face ID.

    With Face ID, Apple says, you can unlock your new iPhone by just looking at it. It is powered by a so-called TrueDepth camera system built into the front of the iPhone X.

    When the camera system sees a person's face, it uses 30,000 unseen dots to “map” the shape and outline of the face. A mathematical model of the face will then be created and stored in the phone.

    The next time the person looks at the iPhone X, the same dots are mapped onto his or her face and compared to the stored model. If the two match, then the phone unlocks. This happens in less than a second.

    Apple says the system is smart. If you change your hairstyle, put on sunglasses or makeup, or use the phone in the dark, Face ID still works.

    Although the technology sounds fancy, there are still concerns. For example, will Face ID work for twins?

    According to Apple, the chance of others to unlock your iPhone X using Face ID is one in a million. Face ID can tell the difference between twins, but the error rating（出错率）rises. So one would need to set a password then.

    Apple also emphasizes that Face ID only unlocks when you stare at it. It is what Apple calls “attention aware”. So the phone won't unlock if you are just glancing at the phone for the time. It won't work either if someone puts the phone at your sleeping face or your photo.

    Recently, many e-commerce platforms, including Didi Taxi, Ctrip, Fliggy, JD ad Taobao, have been uncovered that they are cheating their frequent customers. Their ways are pretty clever. When there are new users or conservative old users, they will give a quite appealing price to attract them into registering and buying goods. However, their big data is not that friendly to the stable users and frequent visitors. The system always offers them higher price for the same products or service. How does this happen? According to the data analysis, the system knows clearly that although they feel the price is high, they will finally pay the bill. By collecting and analyzing users' profiles, buying habits and other information, big data recommends the same products to different users with different prices.

Companies also try other ways to make money, making online consumption far more worrying. For example, video websites always offer 120 seconds' advertisements, which drives people crazy. And even if you pay for the membership to get rid of the ads, you have to “enjoy” 15-second “private” ads. By broadcasting them, companies make huge profits — second to the membership fees. Also, owning 100Mbps network, you still put up with the slow speed when you are downloading a song. You have no choice but to become a VIP when you seek high quality services. Users seem to be lambs(羊羔) among wolves. Even though they say,” Since you have money, I'll charge you more”, we can't do anything about it.

    It pains us that we haven't figured out a way to deal with the problem. The only thing we can do is replacing our iPhones with Android phones if we want to buy a membership card, and applying for new accounts if we want cheaper hotels. Not finding a way to fight back, we can't do anything but accept them passively.

    The national environmental watchdog has declared that boosting efforts to cut air pollution in northern China, especially winter smog from the burning of coal, is a mission for this year.

    Burning coal for winter heating has been listed as one of the primary causes of air pollution, Chen Jining, minister of environmental protection, said on Monday at the annual meeting on environmental protection in Beijing.“As much as 60 percent of smog content is caused by coal burning in the starting phase of each smog”, said Fang Li, an official with Beijing's Environmental Protection Bureau. Therefore, Beijing has declared that it will wipe out coal use in its most rural areas by 2020.

    To start with, Beijing will replace coal-fired heating stoves with those powered by electricity or gas in 400 villages this year, before taking the campaign to the districts of Chaoyang, Haidian, Fengtai and Shijingshan by 2017,said Guo Zihua, a municipal rural development official. Beijing's downtown districts of Dongcheng and Xicheng eliminated coal burning last year, officials said.

    The capital and other places in northern China experienced several smog alerts in November and December, when peak readings were many times higher than the national safety level. Obviously, the situation is deteriorating, and will become a norm. So the government came up with a “smog subsidy (津贴)” for those who work outdoors, and 95 percent of the respondents to a survey support it.

    The Trade Union in Zhengzhou City surveyed subscribers to its official WeChat account and found that 88 percent of nearly 400 respondents said priority should be given to outdoor workers on smoggy days But 9 percent said air pollution affects everyone so it would be unfair to only address the concerns of people who work outdoors.

    Over half of the respondents think the extra subsidy, if applied, could come in the form of protective tools or cash. Twenty-two percent said money is the easiest way. To finance the proposed subsidy, 53 percent think the government and companies should jointly pay the bill, while 44 percent said central and regional governments should be responsible.

    The spine (脊柱) stands at the center of your health, providing your body with structure and support. It also contains a major collection of nerves that deliver electric signals from the rest of the body to your brain. So it's important to take care of it.

    Staying in a good position is one of the most important things to keep your spine healthy. A proper position means standing or sitting while keeping your spins straight, except for its natural bending. Positions play a vital part even when you're asleep. Stomach sleeping is far from a good idea. Many people prefer sleeping on their side, which is in the interests of their spine. Sleeping on your back has lots of benefits yet can cause lower back pain and put some pressure on your spine.

    Staying still for too long — even if your position is good — can be hard on your back. Especially if you work at a task most of the day, it's important to get up and stretch (伸展) periodically. Strength exercises with light weights like push-ups can also help by strengthening the muscles. However, don't overdo the exercise, as repeated movements can hurt the muscles around the spine, as trying to lift heavy weights with poor technique.

    Vitamins also affect the health of your spine. In particular, vitamin B and omega-3 fatty acids help keep nerves healthy. Another important part is vitamin D, which is required for strong bones. Vitamin D can come from some foods, but it's also absorbed from sunlight, so it may help to do some exercises outside. At last, many of the actions necessary to keep a spine healthy are similar to those used to protect your health in other ways. So protect your back, and the rest of the body will benefit.