At the end of every year, Time picks the best 25 inventions that are “making the world better and smarter”. Here we have picked three of this year's inventions that could be a part of your life in the near future.

The levitating(悬浮的) lightbulb

    This special lightbulb was invented by US artist and scientist Simon Morris. He got the idea of making a lightbulb float from hoverboards(悬浮滑板)，which he used to dream of having as a kid.

    But the floating is not the most amazing part. The rejection force between the opposite ends of the magnets(磁铁)，which were put in the bottom of the bulb and in the wooden base, does the job. What's new here is a technology called induction (电磁感应). It allows the lightbulb to get power from the base even they are not in contact.

Shoes that tie themselves

    They're not what you think-shoelaces that tie themselves in the way we tie them. Instead, the new shoes have small motors that control their laces. When you step in them, your feet will hit a sensor（传感器）in the shoes and the motor will automatically tighten the laces.

    But the shoes weren't just designed for lazy people's needs. They could actually give athletes an advantage during competition. They are also useful for people who cannot move their arms or fingers easily.

The no-touch thermometer

    Taking your body temperature usually means putting a thermometer (体温计) in your armpits (腋窝) and staying still for minutes. It may be easy for you, but it's an impossible task for little kids.

    Now, with the new thermometer, users can simply put it 2.5 centimeters from a patient's forechead and press the button, and it can get the reading in two seconds.

    In cooperation with German experts, several scientists from the University of Bradford believe that they finally solved a mystery that has been confusing millions of people: why our hair turns gray with age.

    The researchers came up with their results by examining native hair and cells from human hair follicles（毛囊）. They say the secret turns out to be hidden in catalase（过氧化氢酶）, which is causing hair to turn gray.

    Catalase production goes down with age and stress, allowing hydrogen peroxide（过氧化氢） in the hair to do its favorite job—making hair gray, and then white, by blocking the normal production of melanin（黑色素）. Melanin is our hair's natural pigment that is responsible for the color of hair. It also determines the color of our eyes and skin.

    Dr. Gerald Weizmann, an editor of a journal, says," All of our hair cells make a tiny bit of hydrogen peroxide, but as we get older, this little bit becomes quite a lot, and our hair turns gray and then white."

    The new study brings hope for millions of people who have to color their hair: to finally obtain some shampoo that will decrease levels of hydrogen peroxide and therefore restore gray or white hair to its natural color or even prevent it from turning gray.

    The researchers are already conducting an experiment with such a drug on a few volunteers with gray hair and expect to get the results in the next two to three months. If everything works out, millions of people will choose between this drug and other previously used expensive dyes. However, even if the drug works, it will take at least several years before it can be brought to the market.

The Secret to Happiness

    A new report makes it clear that when it comes to the life satisfaction of UK citizens, the ball is in the government's court. For some time, sensible people have been arguing that governments need to focus less on economic growth and more on the wellbeing（幸福）of citizens. Be careful what you wish for.

    In response to this demand, from 2011 David Cameron instructed the Office for National Statistics to gather data on people's self-reported happiness and life satisfaction. Little practical good has come from this so far, but a new report by George Bangham for the Resolution Foundation is one of the best attempts to make useful sense of the data. He concludes: "The best prospects for policymakers targeting future increases in national wellbeing lie in raising job quality, raising incomes, particularly at the lower end, and policies to improve security in the housing market."

    The age correlation（相关）turns out to be certainly linked to politics, despite the fact that no political party can make a difference to your date of birth. The happiness of pensioners is not just a function of their age, but of policy. On average, 70-year-old boomers today are the most affluent retirees in history, often owning their own homes and in receipt of generous pensions. People of 70 are not going to be as content in 30 or 40 years' time if they are unable to retire, don't own their homes and have small incomes.

    However, there is one respect in which teens and recent retirees are remarkably similar. Compared to other age groups, they tend to inhabit a sweet spot of having high degrees of freedom. The typical 16-year-old has new freedoms without ever having had any serious responsibilities. The typical 70-year-old, having experienced a lifetime of work and family duties, has a very different kind of freedom, one born from relief.

    Besides, it should not surprise us to find that people tend to be happier when they have fewer worries. But this, too, has important political implications. If the government is really interested in raising overall national happiness, it has to make sure as many citizens as possible feel secure in their health, their housing and their incomes. Different states' records in achieving this is one important reason why Nordic countries repeatedly score highly in international life satisfaction surveys and North America underperforms relative to its GDP.

    Whichever way you look at it, there is no escaping the conclusion that increasing wellbeing across society requires joined-up, long-term policy efforts. This is exactly what the Resolution Foundation recommends.

    Donna Strickland is a professor in the Department of Physics and Astronomy. Professor Strickland is one of the recipients( 受领者) of the Nobel Prize in Physics 2018 with Gérard Mourou, her PhD supervisor at the time. They published this Nobel-winning research in 1985 when Strickland was a PhD student at the University of Rochester in New York state. Together they paved the way toward the most intense laser pulses ever created.

    Professor Donna Strickland is only the third woman ever to have won a Nobel Prize in physics. She and her fellow winners were honored for what the Nobel Committee called ground-breaking inventions in laser physics. Professor Strickland devised a way to use lasers as very precise drilling or cutting tools. Millions of eye operations are performed every year with these sharpest of laser beams.

—"How surprising do you think it is that you're the third woman to win this prize? "

—"Well, that is surprising, isn't it? I think that's the story of Maria that people want to talk about — that why should it take 60 years? There are so many women out there doing fantastic research, so why does it take so long to get recognized? "

    Physics still has one of the largest gender gaps in science. One recent study concluded that at the current rates it would be more than two centuries until there were equal numbers of senior male and female researchers in the field.

    The last woman to win a physics Nobel was German-born Maria Goeppert-Mayer for her discoveries about the nuclei of atoms. Before that it was Marie Curie, who shared the 1903 prize with her husband, Pierre. This year's winners hope that breaking this half century hiatus will mean the focus in future will be on the research, rather than the gender of the researcher.

    If you follow these insider tips, your photos will look like you had the place to yourself at the popular tourist attractions.

    Vatican Museums: Vatican City

    The Vatican draws more than five million people each year, and queues can reach four hours during peak season. Christie Hudson, senior communications manager at Expedia, recommends, choosing a skip-the-1ine tour. "This not only lets you avoid the ticket counter, but also includes the use of a private partner entrance." Extra time to visit the Sistine Chapel? Yes!

    Bamboo Forest: Kyoto, Japan

    Bamboo Forest is the most worthy sight in Kyoto. If you're longing to enjoy the pathways and take pictures in total quietness, Kyoto Arashiyama Travel Guide recommends hitting the famous Bamboo Grove Path as early in the morning as possible—think 7 a.m. if you're up for it. Don't miss these hidden treasures you can only witness in Japan.

    Chichen Itza: Yucatán, Mexico

    Home to E1 Castillo and the Temple of the Warriors, Chichen Itza is a must-see. Want to beat the rush? Schedule an early tour that takes place before a site opens to the public. Led by an archaeologist guide, it's full of fascinating insights and facts—without tons of pack-wearing tourists.

    Louvre Museum: Paris, France

    The Louvre is one of the most popular museums on the planet. If waiting around in line to get in isn't the way you prefer to spend your time in Paris, consider purchasing a reserved ticket. This will give you entry to the pyramid within a half-hour window. The Louvre is also open until 9:45 p. m. on Wednesdays and Fridays, if you're up for some late-night art visits.

Street art is a very popular form of art that is spreading quickly all over the world. You can find it on buildings, sidewalks, street signs and trash cans from Tokyo to Paris, from Moscow to Cape Town. Street art has become a global culture and even art museums and galleries are collecting the works of street artists. 

Street art started out very secretly because it was illegal to paint on public and private property without permission. People often have different opinions about street art. Some think it is a crime and others think it is a very beautiful new form of culture. 

Art experts claim that the street art movement began in New York in the 1960s. Young adults painted words and other images on walls and trains. This colourful style of writing became known as graffiti. Graffiti art showed that young people wanted to rebel against society. They travelled around cities to create paintings that everyone could see. In many cases, they had trouble with the police and the local government. 

Street artists do their work for different reasons. Some of them do not like artists who make so much money in galleries and museums. They choose street art because it is closer to the people. Some artists try to express their political opinions in their work. They often want to protest against big firms and corporations. Others like to do things that are forbidden and hope they don't get caught. Advertising companies also use street art in their ads because it gives people the impression of youth and energy. 

Today, the Internet has a big influence on street art. Artists can show their pictures to audience all over the world. Many city residents, however, say that seeing a picture on the Internet is never as good as seeing it alive. The street art movement lives with the energy and life of a big city. There, it will continue to change and grow.