Plastic is easy, convenient, cheap and long-lasting, but it does great harm to the environment.

    Since plastic entered mass production, 8 billion tons have been produced – and we aren't very good at recycling. By 2015, 6,945 tons of plastic waste had formed, with around 9 percent of it getting recycled. About 79 percent of it ends up in landfills or around the environment, including the ocean. We may end up drowning in plastic before long.

    Chemists at Colorado State University have found a polymer（聚酯）that has many of the qualities of plastics – it's light, strong, durable and heat-resistant – but that can be changed back to its original small-molecule（分子）state for complete recycling. Even after being recycled, the polymer can be turned back into its plastic-like state, and this can be done quickly and cheaply.

    This new polymer has all the good qualities of plastics, yet it is relatively easy to make and to recycle. Making it requires room temperature conditions, a short reaction time to bond the monomer（单体）into polymers and only a small amount of the catalyst（催化剂）remains in the end product. It has a high molecular weight, stands up to heat and generally behaves like plastic. Recycling it requires similarly little effort. Mild lab conditions are required and so is a catalyst. Once applied, the polymers are once again monomers in a matter of minutes and can be used to create another product.

    But don't get too excited about this just yet. Scientists stressed that the polymer isn't ready for mass products just yet. There's still plenty of development to do, including making it more economical to produce and recycle.

    An autonomous vehicle designed for making local commerce deliveries was uncovered by Nuro. The vehicle is about the height of an SW but far narrower than a typical car. The electric car features four outside compartments（暗格）—two on each side -to hold separate deliveries. Each compartment can be tailored to a specific use, such as cooking a pizza or refrigerating a package.

    “We can use self-driving technology to deliver anything, anytime, anywhere for basically all local goods and services,” Nuro co-founder Dave Ferguson said. “Consumers used to be okay with two-week paid shipping. It became two-week free delivery, followed by one week, two days, and the same day. Now same-day delivery isn't fast enough for some customers.”

    Nuro isn't alone in building robots for local commerce deliveries. Earlier this month, Toyota, a Japanese car company, uncovered a concept vehicle that could be used for package delivery. A handful of startups—including Starship Technologies, Marble and Dispatch—are testing small robots for deliveries on sidewalks.

    Nuro's vehicle will likely face legal hurdles. Fully autonomous vehicles without a test diver aren't legal in California today, and many companies have shifted testing o states where regulators are more welcoming of autonomous vehicles, such as Arizona.

    Nuro expects to face fewer challenges because it doesn't carry passengers. Nuro's narrow size may also be helpful when navigating streets and avoiding pedestrians. The vehicle isn't equipped with any special features to communicate with pedestrians or other road users. Some companies have tested and patented solutions such as digital screens that signal the car's next move. Ferguson said his team conducted studies and found that such techniques could confuse people. Nuro believes it's better to make sure the car performs predictably, so that human drivers know what to expect from it.

    “We feel by creating this new technology that's going to enable this last mile delivery, we're going to be creating new markets and doing things that previously weren't possible,” Ferguson said. “This is not swapping out jobs with robots. It's creating new markets. There will definitely be new employment opportunities.”

    About aspirin(阿司匹林)

    Aspirin is a commonly used drug which can be taken to relieve discomfort caused by numerous medical problems including headaches, toothache, inflammation and infections. It is also suitable to treat colds and flu-like symptoms, and to reduce a high temperature.

    Who can take aspirin?

    Adults and children over 16 years of age.

    Who should not take aspirin?

    Women who are pregnant, or plan to become pregnant. Aspirin may harm your unborn baby.

    Women who are breast-feeding. Aspirin can pass into your breast milk and may harm your baby.

    People who have any problems with the way the liver works or with the way the kidneys work.

    How to take aspirin:

    Take aspirin after meals, with a full glass of water or milk.

    The recommended dose(剂量) ranges from two to three tablets at a time. Never take more than 4g (12 tablets) in any 24-hour period.

    You must not take these tablets with any other medicine which contains any aspirin or painkiller.

    How to store aspirin:

    Keep all medicines out of the reach and sight of children.

    Store aspirin in a cool, dry place, away from direct heat and light.

    Do not put aspirin in the bathroom because the dampness there can cause it to lose its effectiveness.

    Throw away aspirin that smells strongly of vinegar.

    Possible side effects:

    Feeling sick, increased risk of bleeding, stomach pain, indigestion and heartburn are common. If these effects continue, contact your doctor.

    Ringing in the ears, difficulty breathing, dizziness, and mental confusion are rare. If these occur, stop taking the drug and contact your doctor for further advice.

    This year marks the 170th anniversary of Paul Gauguin's birth. He lived for just 54 years but he packed his brief life with activity.

    The French painter spent his early childhood in Peru before returning to France. As an adult, he continued to travel a lot. Most famously, he spent much of the last decade of his life in Tahiti, an island in southern Pacific Ocean. Indeed, Gauguin is best known for his colorful paintings of Tahitians and their culture.

    The restlessness of this great painter has been normal among modern artists since the middle of the 19th century. They're never satisfied for long with a certain style or way of life. Once something becomes conventional, it's turned down.

    The artistic culture that Gauguin developed from was that of Impressionism (印象派). Painters like Claude Monet had wanted to paint how they saw the world, not how their teachers taught them it should be seen. Gauguin, and similar artists like his friend Vincent van Gogh, moved even further away from "respectable" art than the Impressionists. For them, it was not simply a matter of seeing the world differently, but feeling and thinking about it differently, too.

    Gauguin saw, felt and thought differently from most members of European society. He thought that European culture was too fancy and not spontaneous. This is why he turned to the traditions of other parts of the world, like Africa, and, eventually, Tahiti. Artists like Gauguin used the word "primitive" for these cultures, but not as a negative term. For him, Europe, in becoming modem, industrial and scientific, seemed less natural than other parts of the world.

    In truth, Gauguin's paintings may be unconventional but they are certainly not "primitive". They are the work of a painter with great awareness of what he was doing. It was this awareness that made him such an important painter for those that came after, in the 20th century. When we look closely at the works of Gauguin we begin to understand Pablo Picasso, and especially Henri Matisse, a little better.

    Mill 180 Park is truly a park for the 2lst century, designed to copy all of the great urban parks -Central Park in New York City, Hyde Park in London and Ueno Park in Tokyo. Through the use of computerized sound and some other modern systems, we've brought the outside in, surrounding our visitors with green space and a remarkable sense of the natural world.

    We spent a lot of time trying to learn why these parks are so beloved, what makes them work so well for their sponsors, and how they provide a place of rest for so many.

Each day, 10-year-old Seth asked his mom for more and more lunch money. Yet he seemed skinnier than ever and came home from school hungry. It turned out that Seth was handing his lunch money to fifth grader, who was threatening to beat him up if he didn't pay.

Most kids have been made fun of by a brother or a friend at some point. And it's not usually harmful when done in a playful and friendly way, and both kids find it funny. But when teasing becomes hurtful, unkind, and constant, it crosses the line into bullying and needs to be stopped.

Bullying is intentional torment(折磨)in physical or psychological ways. It can range from hitting, name-calling and threats to blackmailing(勒索)money and possessions. Some kids bully others by deliberately separating them and spreading rumours about them. Others use social media or electronic messaging to make fun of others or hurt their feelings.

It's important to take bullying seriously and not just brush it off as something that kids have to tolerate. The effects can be serious and affect kids' sense of safety and self-worth. In severe cases, bullying has contributed to tragedies, such as suicides and school shootings.

Kids bully for a variety of reasons. Sometimes they pick on kids because they need a victim—someone who seems emotionally or physically weaker, or just acts or appears different in some way—to feel more important, popular, or in control. Although some bullies are bigger or stronger than their victims, that's not always the case.

Sometimes kids bully others because that's the way they've been treated. They may think their behavior is normal because they come from families or other settings where everyone regularly gets angry and shouts or calls each other names.

Unless your child tells you about bullying—or has visible injuries—it can be difficult to figure out if its happening.