“One thing I enjoy about my job is that I can work on something that is actually active,” says Game McGimsey, an American volcanologist (火山学家). Part of his job includes keeping an eye on Alaska's many active volcanoes and giving people a heads-up when a volcano might erupt (喷发).

    Like most jobs in the sciences, volcanology requires a lot of education. McGimsey received an undergraduate degree in geology at the University of North Carolina, then landed an internship (实习期) with a geologist at the USGS (美国地质勘探局) whose area of expertise was volcanoes. After earning a graduate degree at the University of Colorado, McGimsey accepted a job with the USGS and has been with the Alaska Volcano Observatory for 25 years.

    Volcanoes can influence the world in ways we might not think about. For example, on Dec. 15, 1989, a 747 jetliner (a large airplane) flew through a thick ash (灰) cloud produced by Mount Redoubt, an Alaskan volcano that hadn't erupted in 25 years. The ash caused all four engines to die, and the plane's electronics went dead.

    “The plane was within several thousand feet of flying into the mountains below when the pilots got a couple of the engines restarted and landed safely in Anchorage,” McGimsey says. It cost nearly $80 million to repair the damage to the plane.

    Such situations show just how dangerous volcanoes can be. However, volcanologists know the risks and are prepared to protect themselves.

    “There is certainly a higher danger level in volcanology than some other jobs,” McGimsey admits. “We understand how serious the danger is, and we don't like taking unnecessary chances. We avoid getting too close to an erupting volcano, because it's not worth injury or death simply to get a rock or a photograph.”

    The iPhone, the iPad: each of Apple's products sounds cool and has become a fad(一时的风尚). Apple has cleverly taken advantage of the power of the letter “i” --and many other brands are following suit. The BBC's iPlayer--which allows Web users to watch TV programs on the Internet--used the title in 2008. A lovely bear--popular in the US and UK--that plays music and video is called “iTeddy”. A slimmed-down version(简装本) of London's Independent newspaper was started last week under the name “i”.

    In general, single-letter prefixes(前缀) have been popular since the 1990s, when terms such as e-mail and e-commerce(电子商务) first came into use.

    Most “I” products are targeted at(针对) young people and considering the major readers of Independent's “I”, it's no surprise that they've selected this fashionable name.

    But it's hard to see what's so special about the letter “i”. Why not use “a”, “b”, or “c” instead? According to Tony Thorne, head of the Language Center at King's College, London, “i” works because its meaning has become ambiguous. When Apple uses “i”, no one knows whether it means Internet, information, individual or interactive, Thorne told BBC Magazines. “Even when Apple created the iPod, it seems it didn't have one clear definition(定义),” he says.

    “However, thanks to Apple, the term is now connected with portability (轻便).” adds Thorne.

    Clearly the letter “i” also agrees with the idea that the Western World is centered on the individual. Each person believes they have their own needs, and we love personalized products for this reason.

    Along with “Google” and “blog”, readers of BBC Magazines voted “I” as one of the top 20 words that have come to define the last decade(十年).

    But as history shows, people grow tired of fads. From the 1900s to 1990s, products with “2000” in their names became fashionable as the year was connected with all things advanced and modern. However, as we entered the new century, the fashion disappeared.

    If you live in a big city, there are many thing to drive you crazy on your daily route, and it's not just overcrowded subway trains.

    Vicky Zhao is a mainlander working in Hong Kong. For her, one thing she can't put up with is people standing on the wrong side of the escalator(自动扶梯) in subway stations. "Escalators help us move faster and save time. It isn't a place to rest," the 24-year-old says. "I often see tourists block the way with their suitcases or chatting on the escalators during rush hours. It annoys me to no end."

    Admitting she is not the patient type, Zhao says things are much better in Hong Kong than in cities on the mainland where "stand right, walk left" signs are often ignored.

    The logic behind the "stand right, walk left" escalator etiquette(礼仪) seems obvious. Even though you may want to catch your breath while you're transported up or down, you should still consider others and leave enough space for people in a hurry, so that they can run and catch the train.

    Many cities' escalators, including London's and Beijing's, use the "stand right, walk left" system to speed up the flow of people. (Australia is an exception and you should stand on the left side instead.) But some cities discourage people from moving on escalators out of safety reasons. In Hong Kong's subway stations there are regular announcements asking people to "stand still" on escalators. Even so, most people in this fast-paced city observe the "stand right, walk left" etiquette.

    But the people who stand on escalators defend themselves by telling the walkers not to be so impatient. The BBC quotes one stander as saying: "If the person is in such a rush, why not just take the stairs? Even when the escalator is packed and there's nowhere to move, I see these same people complaining about not being able to pass."

    Whatever the escalator etiquette is in the place you live or visit, do what most people are doing and always be mindful of others: leave enough space between each other, don't stay at the end of the escalator, and if someone is blocking your way, a simple "excuse me" is enough.

    Since English biologist Charles Darwin published On the Origin of Species in 1859, scientists have vastly improved their knowledge of natural history. However, a lot of information is still of the speculation, and scientists can still only make educated guesses at certain things.

    One subject that they guess about is why some 400 million years ago, animals in the sea developed limbs (肢) that allowed them to move onto and live on land.

    Recently, an idea that occurred to the US paleontologist (古生物学家) Alfred Romer a century ago became a hot topic once again.

    Romer thought that tidal (潮汐的) pools might have led to fish gaining limbs. Sea animals would have been forced into these pools by strong tides. Then, they would have been made either to adapt to their new environment close to land or die. The fittest among them grew to accomplish the transition (过渡) from sea to land.

    Romer called these earliest four-footed animals “tetrapods”. Science has always thought that this was a credible theory, but only recently has there been strong enough evidence to support it.

    Hannah Byrne is an oceanographer (海洋学家) at Uppsala University in Sweden. She announced at the 2018 Ocean Sciences Meeting in Oregon, US, that by using computer software, her team had managed to link Homer's theory to places where fossil deposits (沉积物) of the earliest tetrapods were found.

    According to the magazine Science, in 2014, Steven Balbus, a scientist at the University of Oxford in the UK, calculated that 400 million years ago, when the move from land to sea was achieved, tides were stronger than they are today. This is because the planet was 10 percent closer to the moon than it is now.

    The creatures stranded in the pools would have been under the pressure of “survival of the fittest”, explained Mattias Green, an ocean scientist at the UK's University of Bangor. As he told Science, “After a few days in these pools, you become food or you run out of food... the fish that had large limbs had an advantage because they could flip (翻转) themselves back in the water.”

    As is often the case, however, there are others who find the theory less convincing. Cambridge University's paleontologist Jennifer Clark, speaking to Nature magazine, seemed unconvinced. “It's only one of many ideas for the origin of land-based tetrapods, any or all of which may have been a part of the answer,” she said.

    Kerala, India, has placed a tax on hamburgers, pizza and other fast food. The 14.5 percent tax will be added to foods at restaurants such as McDonald's, Pizza Hut and Burger King.

    The tax is being called a "fat tax" because it adds cost to foods considered high in fat and calories. It is the first fast food tax enacted in India, where obesity levels are rising in the growing middle class.

    Kerala's Finance Minister Thomas Isaac suggested the tax after learning of similar measures in other countries. He hopes it will get people to choose to eat healthy food, which he said is "going out of fashion."

    Dr. Anoop Misra at New Delhi's Fortis Hospital strongly supports the" fat tax" as a way to reduce the number of diabetes cases in young people.

    A government finance official in central Gujarat says that the state is considering a similar 14.5 percent tax." This idea can also be adopted in the state, as we also have high consumption of junk and unhealthy food," the official said.

    Critics of the tax say it probably will not stop people from buying fast food. IT engineer Gaurav Singh wants the government to focus on education and awareness instead of taxing fast food.

    "The one food that is eaten widely in Kerala is the 'paratha', which is basically high in fat, high in refined(精制的)flour, and it is cheap. It can't be taxed because it is highly unorganized."

    Some doctors and health experts say the tax should also include other snack foods and sugary drinks sold across the country.

    One fast food customer In New Dehli, Vijay Deoli believes the government should deal with more important issues. "First you have to clear up the air, the water, etc. This is a small thing."

    Others say the government should do more to bring attention to fast food and obesity rather than changing people's choices.

    Many health experts agree that bringing attention to the issue is important. But Dr. Misra thinks education alone does not work.

    He compared the tax to a law passed several years ago that got people to wear seat belts to avoid paying a fine. "Laws can change people's habits."

    Japanese researchers made a botanical announcement on Monday that quickly circled the world. They had developed a banana with an eatable peel (皮)—the Mongee banana.

    The technique used by scientists at D&T Farm is called "freeze thaw awakening". The process involves starling banana trees out in an environment that's nearly minus-80 degrees Fahrenheit, then moving the trees with their still-ripening bananas to a climate of around 80 degrees - an environment banana trees typically grow in the entire time. The extreme temperature change puts the banana's growth into a superfast-speed mode. In this case, the fruit ripens before the skin can catch up. The result is soft and thin skin that hasn't fully developed.

    The banana has been produced only in small amount so far, so customers face a steep bill to save themselves the bother of peeling their banana: it is currently priced at 648 yen ($6) a piece. There's also the question of whether a banana peel is actually worth eating and whether regular banana peels had, rather suddenly, become too big a problem for people who slip on them to bear anymore.

    And what about shipping? For most of the fruit's history, the peel has provided protection, allowing it to travel long distances from where it's grown to nearly every country on Earth. A softer banana would be a step back from regular banana varieties that travel thousands of miles.

    But the banana in the news is arguably good, particularly for a fruit that rarely receives its share of attention. Bananas are the most  consumed fruit in Japan, and also in the U.S. So even if eatable-peel bananas don't ensure plentiful bananas, or even necessarily nutritious bananas, they still look great on Instagram, which probably ensures them a future in Japan's famous luxury (奢侈) fruit markets.