A handshake is one of the most common ways to greet others, but US President Donald Trump's unusual method has been put under the microscope lately.

    Much like an arm wrestler in a match, the recently-elected leader has a habit of yanking (猛拉) people's hands toward himself during handshakes. And while a typical handshake is only brief, the one between him and Japanese Prime Minister Shinzo Abe on Feb 10 lasted a full 19 seconds.

    Simply having a strong hand is not the explanation here. According to Darren Stanton, a body language expert from the UK, while handshakes are usually an exchange of kindness, Trump uses his as a way to show power and control, regardless of how uncomfortable it makes people. “It is as if to say, 'Hey, I'm in charge, don't mess with me,' ” Stanton told The Independent.

    Apart from Trump's “yank-shake”, there are other ways people display power with their hands. At business talks or political meetings, for example, some people may rotate (旋转) their wrists during handshakes so that their hand ends up on top instead of underneath. Some may squeeze so hard that it leaves the other person's hand in pain.

    According to Stanton, by pulling people into his personal space, Trump is also testing whether they are willing to cooperate with him. “For example, if someone was resistant to being yanked towards him and stood their ground, he would know that he has work to do with them before he got what he wanted,” Stanton told Express.

    This is probably why on Feb 13 when Canadian Prime Minister Justin Trudeau visited the White House, all eyes were on how he was going to handle Trump's handshake. Fortunately, Trudeau managed to avoid the embarrassment by grabbing Trump's shoulder to stop himself being pulled in. Afterward, some Twitter users wrote that this proved Trudeau's strong leadership, with one even calling the moment “one of Canada's greatest victories”.

    Vice magazine summed up the exchange between the two leaders as: “... no regular handshake. This was the first shot in a bloodless war.”

    No country in the world has more daily newspapers than the US. There are almost 2,000 of them, as compared with 180 in Japan, 164 in Argentina and 111 in Britain. The quality of some American papers is extremely high and their views are quoted all over the world. Famous dailies like the Washington Post or the New York Times have a powerful influence all over the country. However, they are not national newspapers in the sense that The Times is in Britain or Le Monde is in France, since each American city has its own daily newspaper. The best of these presents detailed description of national and international news, but many tend to limit themselves to state or city news.

    Like the press in most other countries, American newspapers range from the “sensational” which feature crime and gossip (闲谈), to the “serious”, which focus on factual news and the analysis of world events. But with few exceptions, American newspapers try to entertain as well as give information, for they have to compete with the attraction of television.

    Just as American newspapers satisfy all tastes, so do they also try to attract readers of all political parties. A few newspapers support extremist (极端主义的) groups on the far right and on the far left, but most daily newspapers try to attract middle-of-the-road Americans who are moderate (中立的). Many of these papers print columns by well-known journalists of different political and social views, in order to present a balanced picture.

    As in other countries, American newspapers can be either responsible or irresponsible, but it is generally accepted that the American press serves its country well and that it has more than once courageously exposed political scandals (丑闻) or crimes, for instance, the Watergate Affair (水门事件). The newspapers drew the attention of the public to the horrors of the Vietnam War.

    Dr. Sasaki knew the first-night effect probably has something to do with how humans evolved.

    The puzzle was what benefit would be gained from it when performance might be affected the following day. She also knew from previous work conducted on birds and dolphins that these animals put half of their brains to sleep at a time so that they can rest while remaining alert enough to avoid predators (捕食者). This led her to wonder if people might be doing the same thing. To take a closer look, her team studied 35 healthy people as they slept in the unfamiliar environment of the university's Department of Psychological Sciences. The participants each slept in the department for two nights and were carefully monitored with techniques that looked at the activity of their brains. Dr. Sasaki found, as expected, the participants slept less well on their first night than they did on their second, taking more than twice as long to fall asleep and sleeping less overall. During deep sleep, the participants' brains behaved in a similar manner seen in birds and dolphins. On the first night only, the left hemispheres (半球) of their brains did not sleep nearly as deeply as their right hemispheres did.

    Curious if the left hemispheres were indeed remaining awake to process information detected in the surrounding environment, Dr. Sasaki re-ran the experiment while presenting the sleeping participants with a mix of regularly timed beeps (蜂鸣声) of the same tone and irregular beeps of a different tone during the night. She worked out that, if the left hemisphere was staying alert to keep guard in a strange environment, then it would react to the irregular beeps by stirring people from sleep and would ignore the regularly timed ones. This is precisely what she found.

    When one of your car tires goes flat, there are two things you can do, you can complain and change it or, if you don't have a spare, stand helplessly beside the road and hope someone comes to your rescue. Now comes a third choice, called Quickwheel. It is designed to get disabled motorists rolling again as quickly as possible.

Quickwheel is basically a tiny emergency trailer—complete with three tough little wheels of its own-- that supports the flat tire and enables the motorists to drive to a service station without losing much time or expending much energy. The product is made in the US. Company, Quickwheel Inc. of Greenwich, Connecticut. According to the firm's president, Robert Bockweg, the product meets each of the major worries that customers relate with flat tires: safe, lost time and physical labor.

    To use it, motorists simply unfold the product to its fully extended position, set it in front of the disabled tire, drive the car onto the Quickwheel's ramp (斜板) and fix a special safety strap over the tire. The tire is then locked in Quickwheel's metal frame. Its three wheels do the rest of the work. According to Quickwheel Inc, its product can be driven “for miles” at the speed of up to 45 miles per hour “without any noticeable change in the vehicle's braking or steering operation”. The company also says that it can be used on just about any type of car, jeep, mini-van or trailer. (拖车)

    Bockweg says that Quickwheel will be sold first in the United States, at a price of 150 dollars. Sales agreements now being talked over should make the product ready for use in Japan, Canada and Western Europe in the near future.

    Stocky, slow-moving whale, rarely grows beyond 15 metres in length

    Flippers are a third of body length; variable dorsal fin size and shape; saw-toothed trailing edge on flukes, often raised when diving

    Bumpy tubercles on top of head

    Body colour is dark brown to black; often extensive white on flippers and underside of body and flukes; such patterns enable individual recognition

    Bushy blow, occasionally V-shaped

    270-400 olive baleen plates

    Humpback whales belong to the rorqual (groove-throated) family, which includes fin, sei, Bryde's, minke and blue whales. The big family migrate between winter tropical breeding areas (North West Shelf, Great Barrier Reef, New Caledonia, Vanuatu, Fiii, Tonga) and summer Antarctic feeding areas. Once common in New Zealand waters, humpbacks are now rarely seen and may migrate further offshore. Males compete for mates either by physical fight or by song. Females give birth to their young every two to three years; some non-breeding females probably remain in the southern waters during winter. Young humpback whales return to their area of birth but in later life some wander between breeding areas. Humpbacks eat small shrimps and other schooling prey, such as fish, forming small, cooperative groups of two to three individuals to feed.

    Similar species: Easily identifiable due to a 'hump' back when submerging, but at a distance may be confused with other species that raise their flukes when diving, such as sperm, right and blue whales.

    Protection status: Recovering well from past whaling and now numerous in some former migration and aggregation areas, rarely seen in others.

A pair of researchers with Leibniz University of Hannover has demonstrated the means by which robots might be programmed to experience something similar to pain in animals. As part of their demonstration at last week's IEEE International Conference on Robotics and Automation held in Stockholm, Johannes Kuehn and Sami Haddaddin showed how pain might be used in robots, by interacting with a BioTac fingertip sensor on the end of a Kuka robotic arm that had been programmed to react differently to differing amounts of pain.

The idea of developing an artificial robot nervous system may seem contrary to all expectations, but Kuehn says doing so is important in the same way that it is good for humans to feel pain. "Pain is a system that protects us, "says Kuchn. "When we avoid the source of pain, it helps us not get hurt. "So when robots can feel and react to pain, they will become smart enough to avoid it. The more dangerous the robot registers the threat to be, the faster it will withdraw and avoid the source of danger. Additionally, Kuehn and Haddadin say humans working alongside robots that feel pain, especially those in heavy machinery, will be protected around them.

They have tested out some of their ideas using a robotic arm with a fingertip sensor that can detect pressure and temperature. It uses a robot-tissue patch(小片)modeled on human skin to decide how much pain should be felt and thus what action to take. For example, if the arm feels light pain, it slowly withdraws until the pain stops, and then returns to its original task; severe pain, meanwhile, causes the arm to go into a kind of lockdown mode until it can get help from a human operator.

Such robots are likely to raise a host of questions, of course, if they become more common —if a robot acts the same way a human does when touching a hot plate, are we to believe it is truly experiencing pain? Only time will tell of course, but one thing that is evident, Kuehn and Haddadin's work could lead to robots that are more human-like than ever.