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    You may like chewing gum (口香糖) after meals to stop your breath smelling bad; or your mother might use a special neutralizer (调理剂) to protect her permed hair (烫发). But have you thought about the chemical principles behind such everyday actions?

    On March 2, the Senior 3 students from the IB (International Baccalaureate, 国际文凭) classes at Beijing Huijia Private School presented their discoveries, all in fluent English. This kind of seminar is held every year to show the achievements of the IB chemistry experiment lessons offered by the school. IB is a qualification based on a common curriculum (课程) for students aged 16-18 in any country and is recognized by universities everywhere.

    "Once I saw an advertisement for xylitol (木糖醇) gum," recalled Zhang Xinju. "Suddenly an idea came to my mind: are there any chemical reactions when the xylitol is working on our teeth?"

    Zhang and his partner Bu Xuan visited several hospitals to try and find out. "Doctors know that xylitol can protect teeth, but few could explain how the chemical reactions happen," said the 17-year-old boy.

    Presenting the results of their research in English to an audience of Chinese and foreign judges was never a problem for the students.

    "Textbooks for IB students are in English, and our teachers speak in English," explained Wei Duan and Han Yu, whose research topic was "The Acid-Base Reaction (酸碱反应) in the process of Hair-Perming".

    "In Senior 1 we often referred to Chinese textbooks, but we found we could understand and express it all in English by the second year."

    Lu Jiang, the school's IB chemistry teacher and China's only IB vice-examiner, is proud that her students can apply scientific theories they learn in class to daily life.

    "You might have learned these facts from you kindergarten teachers, but few think about the theories behind them," Lu said. "This kind of practice is intended to develop the scientific thinking they will need in their future studies."

C

    As cultural symbols go, the American car is quite young. The Model T Ford was built at the Piquette Plant in Michigan a century ago, with the first rolling off the assembly line（装配线） on September 27, 1908. Only eleven cars were produced the next month. But eventually Henry Ford would build fifteen million of them.

    Modern America was born on the road, behind a wheel. The car shaped some of the most lasting aspects of American culture: the roadside diner, the billboard, the motel, even the hamburger. For most of the last century, the car represented what it meant to be American—going forward at high speed to find new worlds. The road novel, the road movie, these are the most typical American ideas, born of abundant petrol, cheap cars and a never-ending interstate highway system, the largest public works project in history.

    In 1928 Herbert Hoover imagined an America with "a chicken in every pot and a car in every garage." Since then, this society has moved onward, never looking back, as the car transformed America from a farm-based society into an industrial power.

    The cars that drove the American Dream have helped to create a global ecological disaster. In America the demand for oil has grown by 22 percent since 1990.

    The problems of excessive（过度的）energy consumption, climate change and population growth have been described in a book by the American writer Thomas L. Friedman. He fears the worst, but hopes for the best.

    Friedman points out that the green economy（经济）is a chance to keep American strength. "The ability to design, build and export green technologies for producing clean water, clean air and healthy and abundant food is going to be the currency of power in the new century."

    A new web standard is expected to kill passwords, meaning users will no longer have to remember difficult logins(登录) for each and every website or service they use.

    The Web Authentication (WebAuthn网络认证) standard is designed to replace the password with tools that users already own, such as a security key, a smart phone, a fingerprint scanner or webcam. Instead of having to remember long characters, users can authenticate their login with their body or something they have, communicating directly with the website through Bluetooth, USB or NFC.

    "WebAuthn will change the way that people access the Web," said Jeff Jaffe, CEO of the World Wide Web Consortium (W3C), the body that controls web standards. One example of how WebAuthn will work is that when a user visits a site, they put in a user name and then get a message on their smart phone. Tapping on the message on their phone then logs them into the website without the need for a password.

    WebAuthn promises to protect users against phishing attacks(钓鱼攻击) and the use of stolen information as there will be nothing to steal, the authentication sign is produced and used once by their special tool each time the user enters.

    "After years of increasingly serious data and password being stolen, now it is the time for service providers to end their dependency on easily-attacked passwords and use phishing-resistant FIDO Authentication(快速身份认证联盟) for all websites and apps," said Brett McDowell, CEO of the FIDO Alliance, one of the bodies pushing the new standard.

    WebAuthn should also help people use special login details for each and every service they use, instead of using the same login and password for every site, which many people still do, leaving them further attacked if one site is hacked(黑客攻击).

    The W3C has moved WebAuthn to what's called the "candidate recommendation" stage – the last-but-one step before it becomes an approved web standard – inviting sites and services to begin using it. The web standards body announced that Google, Microsoft and Mozilla had been devoted to supporting WebAuthn, meaning that all major web explorers except Apple's Safari will use the new standard.

    "While there are many web security problems and we can't fix them all, relying on passwords is one of the weakest links. With WebAuthn's solutions we are removing this weak link," said Jaffe.

    Several sites and services already use similar methods to enter, including Google and Facebook, which can both be entered using a USB security key. But a single cross-platform, cross-service standard approved by the W3C will mean that many more sites and services will be able to kill the password as the login method.

    WebAuthn is the top of many years of work and the change will not happen overnight. But as it increasingly seems unavoidably that our email or other online services will get hacked into, removing the password is an important step in improving online security and making using sites and services easier.

Don't Drop the Ball

    Drop prevention risk assessment is really important. Everyone knows objects get dropped on work sites – there's nothing radical about that. In Australia, mining has the third highest fatality rate of any industry (4.4 fatalities per 100,000 workers in 2015), and in less well-documented areas like India the fatality rate is even higher. A lot of these fatalities come from dropped objects. It's worth trying to address this and work out just how big the risk is and where it comes from. At the end of the day, safety should be a priority in any industry and it should come as no surprise that addressing safety issues early can actually save money, long-term, for companies. It doesn't look good for a mining company if people are getting injured and equipment damaged from falling objects.

    The risks from dropped objects come from all sorts of areas; it's not just a matter of dropped tools. We're talking about sites characterized by a lot of activities, where all sorts of things can come loose or fall, whether its light fittings or objects like rocks falling off transporting belts. The risks are largely personal but are also financial: if a piece of equipment gets damaged it will need replacing. That's a pretty strong inspiration for companies to address these risks. In terms of frequency, here in Australia we're looking at around 18% of compensation claims coming from workers being hit by moving objects, but those are just the claims – the frequency is likely higher. Around 28% of deaths and injuries come from such incidents, too. As I said earlier, that's just Australia; some industries don't keep statistics, but I wouldn't be surprised to find other countries report comparable rates. That's a lot of accidents that could be prevented with adequate safety measures.

    It's important to take an active approach. It's a lot easier and cheaper to address these risks during the installation or maintenance phases by adding barriers to the inside of guard railings on walkways and transporting systems and adding nets to fixed devices. There are safety mechanisms available, but it's up to the companies to install them. It is a lot more efficient to add barriers right from the start rather than waiting for an accident and then thinking, "Should we be safer?", when they should have reduced these risks from the start.

    The new social robots, including Jibo, Cozmo, Kuri and Meccano M.A.X., bear some similarities to assistants like Apple's Siri, but these robots come with something more. They are designed to win us over not with their smarts but with their personality. They are sold as companions that do more than talk to us. Time magazine cheered for the robots that "could fundamentally reshape how we interact with machines." But is reshaping how we interact with machines a good thing, especially for children?

    Some researchers in favor of the robots don't see a problem with this. People have relationships with many kinds of things. Some say robots are just another thing with which we can have relationships. To support their argument, roboticists sometimes point to how children deal with toy dolls. Children animate (赋予…生命) dolls and turn them into imaginary friends. Jibo, in a sense, will be one more imaginary friend, and arguably a more intelligent and fun one.

    Getting attached to dolls and sociable machines is different, though. Today's robots tell children that they have emotions, friendships, even dreams to share. In reality, the whole goal of the robots is emotional trickery. For instance, Cozmo the robot needs to be fed, repaired and played with. Boris Sofman, the chief executive of Anki, the company behind Cozmo, says that the idea is to create "a deeper and deeper emotional connection ... And if you neglect him, you feel the pain of that." What is the point of this, exactly? What does it mean to feel the pain of neglecting something that feels no pain at being neglected, or to feel anger at being neglected by something that doesn't even know it is neglecting you?

    This should not be our only concern. It is troubling that these robots try to understand how children feel. Robots, however, have no emotions to share, and they cannot put themselves in our place. No matter what robotic creatures "say", they don't understand our emotional lives. They present themselves as empathy machines, but they are missing the essential equipment. They have not been born, they don't know pain, or death, or fear. Robot thinking may be thinking, but robot feeling is never feeling, and robot love is never love.

    What is also troubling is that children take robots' behavior to indicate feelings. When the robots interact with them, children take this as evidence that the robots like them, and when robots don't work when needed, children also take it personally. Their relationships with the robots affect their self-esteem (自尊). In one study, an 8-year-old boy concluded that the robot stopped talking to him because the robot liked his brothers better.

    For so long, we dreamed of artificial intelligence offering us not only simple help but conversation and care. Now that our dream is becoming real, it is time to deal with the emotional downside of living with robots that "feel".