【推荐1】People feel good about recycling, maybe even more so when it comes to electronics. While electronics recycling isn’t bad, making it a panacea(万能药) for the e-waste problem we currently have certainly is. Unfortunately, that’s how we think of recycling and companies are eager to jump on that trend to appear more “green”.

A case in point: Apple. In 2016, there was lots of report on Liam, a robot able to dismantle(拆解) an iPhone in just 11 seconds--- a good way to recycle 1.2 million units a year. That sounds amazing until you take into account the fact that Apple had actually sold 231 million new iPhones the year before. Actually, Liam is the perfect symbol for recycling in the field of high-tech: a drop of green water in an ocean of pollution.

According to a recent UN report, the US produces about 6.3 million tons or 14% of the world’s electronic waste. Worldwide, almost 45 million tons of electronic waste were produced in 2016. Among them, only 20% has been recycled in some shape or form. The remaining 80% made its way to a more environmentally damaging end at the landfill(垃圾清理场).

Of course, we can say it’s time to double our recycling efforts. However, the huge amount of e-waste is impossible to deal with. The UN report points out that while there is an increased focus on recycling today compared to the past, the efforts to reuse used devices simply can’t keep pace with the high consumption rates for new devices.

And in their environmental responsibilities report, Apple admits that 77% of the carbon footprint of their electronics comes from its actual use. The environmental effect of replacing a device, even if it is recycled after, remains significant.

【推荐3】More and more students are going abroad for their furtherstudy Do you want to know some famous colleges and universities?

Started in 1636, Harvar University is the oldest of all the colleges and universities in the United States.Yale University, Princeton University, Columbia University and DartmouthCollege were opened soon after Harvard University. In the early years, these schools weare much alike. Only young men went tocollege. All the students studied the same subjects,and everyonelearned Latin, Greek and Hebrew. Little was known about science then, and one kind of school could teach everything that was known about the world. When the students graduated, most of them became ministers or teachers. In 1782, Harvard University started a medical school for young men who wanted to become doctors. Later, lawyers could receive their training in Harvard University’s law school. In 1825, besides Latin and Greek, Harvard University began teaching modern languages, such as French and German. Soon it began teaching American history. As knowledge increased, Harvard University and other colleges began to teach many new subjects. Students were allowed to choose the subjects that interested them.

Today, there are many different kinds of colleges and universities. Most of thethem are made up of smaller schools that deal with special fields of learning. There’s so much to learn that one kind of school can’t offer it all.

【推荐1】Race walking shares many fitness benefits with running, research shows, while most likely contributing to fewer injuries. It does, however, have its own problem.

Race walkers are conditioned athletes. The longest track and field event at the Summer Olympics is the 50-kilometre race walk, which is about five miles longer than the marathon. But the sport’s rules require that a race walker’s knees stay straight through most of the leg swing and one foot remain in contact with the ground at all times. It’s this strange form that makes race walking such an attractive activity, however, says Jaclyn Norberg, an assistant professor of exercise science at Salem State University.

Like running, race walking is physically demanding, she says. According to most calculations, race walkers moving at a pace of six miles per hour would burn about 800 calories (卡路里) per hour, which is approximately twice as many as they would burn walking, although fewer than running, which would probably burn about 1,000 or more calories per hour.

However, race walking does not pound the body as much as running does, Dr Norberg says. According to her research, runners hit the ground with as much as four times their body weight per step, while race walkers, who do not leave the ground, create only about 1.4 times their body weight with each step.

As a result, she says, some of the injuries associated with running, such as runner’s knee, are uncommon among race walkers. But the sport’s strange form does place considerable stress on the ankles and hips, so people with a history of such injuries might want to be cautious in adopting the sport. In fact, anyone wishing to try race walking should probably first consult a coach or experienced racer to learn proper technique, she says. It takes some practice.

【推荐2】Endangered polar bears are breeding with grizzly bears, creating “pizzly” bears, which is being driven by climate change, scientists say.

As the world warms and Arctic sea ice thins, hungry polar bears are being forced ever further south, where they meet grizzlies, whose ranges are expanding northwards. And with that growing contact between the two come increasing hybrids (杂交种), “pizzly” bears.

With features that could give the hybrids an advantage in warming northern habitats, some scientists guess that they could be here to stay. “Usually, the hybrids, ‘pizzly’ bears aren’t better suited to their environments than their parents, but these hybrids are able to search for a wider range of food sources,” Larisa DeSantis, an associate professor of biological sciences at Vanderbilt University, told Live Science.

The rise of “pizzly” bears appears with polar bears’ decrease: their number may go down by more than 30% in the next 30 years. This sudden fall is related partly to “pizzly” bears taking up polar bears’ ranges, but also to polar bears’ highly specialized diets.

“Polar bears mainly ate soft foods even during the Medieval Warm Period, a previous period of rapid warming,” DeSantis said, referring to fat meals such as seals. “Although all of these hungry polar bears are trying to find other food sources, like seabird eggs, it could be a tipping point for their survival.” Actually, the calories they gain from these sources do not balance out (抵消) those they burn from searching for them. This could result in a habitat ready for the hybrids to move in and take over, leading to a loss in biodiversity if polar bears are replaced.

“We’re having great impacts with climate change on species,” DeSantis said. “The polar bear is telling us how bad things are. In some sense, ‘pizzly’ bears could be a sad but necessary compromise (妥协) given current warming trends.”

【推荐3】We live in a world where it's often not easy to find someone to trust. A smiling person always inspires trust. Even economists consider that smiles are valuable.A smile may increase other people's trust by about 10%.

People may also smile when they are caught doing bad things.According to a study made by LaFrance and Hecht，this can in fact be to their own advantage.We have a tendency to be kinder towards those who make mistakes if they wear a smile while being caught.Even a guilty smile may help you get away pretty easily when you make mistakes.

We may also smile when we hear a piece of good news.In this case，women tend to smile more often than men.Smiling can also be a means of reducing the pain caused by a troubling situation.Even if we force ourselves to smile when we don't want to，this may be enough to lift our spirits just a little bit.

When we feel angry or anxious，our attention tends to narrow down.We can no longer see what's going on around us and we can only notice what is in front of us.But if we smile，we feel better and increase flexibility of our attention and the ability to think.Smiling can help us focus and understand better.

“Keep on smiling，and the world will smile with you.”One of the greatest social pleasure is to smile and be smiled to in return，especially because this comes like a natural thing.

People who smile often live longer.A study based on some pictures taken of some baseball players suggested that those who used to smile a lot survived about 7 years longer than those who did not smile very often.