Recently, online hike-sharing has become the new favorite in China. In major cities, bikes in, yellow, orange, blue, white and green, can be seen almost everywhere on the street. It seems that these bikes appeared suddenly, adding a new beautiful scenery to Chinese cities.

    Both the market and the public welcome online bike-sharing, but is it really a promising business? Well, it depends. After all, online bike-sharing platforms can never get away with huge operating cost and uncertain government policy.

    Some theorists might say that online bike-sharing platforms can earn a fortune simply through deposit. Since users will always need to rent bikes, their deposit will always be kept to online bike-sharing platforms.

    However，although online bike-sharing platforms may be able to use the deposit for other purposes at the primary stage, they will have to set up a special account, so that the deposit shall be used specially for its designated (指定的) purpose. As the market gets increasingly mature, they will have to do so whether to be responsible for users or in consideration of possible government regulations.

    Now that online hike-sharing platforms can，t make profit through deposit，how can they become profitable as fiercer market unfolds? Although Hu Weiwei, CEO of Mobike, stated in an article that she would take Mobike as charitable(慈善的) project if she failed, running a startup is absolutely different from managing a charity organization. After all , she has to pay back investors' billions of investment(投资).

    To make profit, online bike-sharing platforms might have toincrease rent fee for each trip, just as Didi did

    From this aspect, it might be a really good business. If we consider full screen ads fee, recommendation fee for business owners, etc. , its annual income might reach at least RMB 15 billion. If we consider the huge operation cost, including bike repairs，bikes' service life and labor cost, there might not be much net profit left. After all, offline operation cost has always been an unbearable burden for such internet plus mode-based startups.

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    The Best Time to Visit These Pricey Destinations

    If you're going to shell out on a vacation, then you might as well do it right. With that in mind, we've asked a few experts for tips on when to visit some of the most expensive places across the globe. Here's what they had to say.

    Botswana

    Hotels in Botswana are second only to Dubai in terms of average cost per person, per night, at around $257. To make the most of your time there, consider an autumn visit, suggests Sarah Faith of Responsible Travel. “The heat peaks in October—this is the best time to go and see wild animals as they gather around in the Okavango Delta”, says Faith. While wildlife viewing is incredible in Botswana, there's much to enjoy away from the wilderness, too.”

    New York City

    New York is the second-most expensive holiday destination overall and the most expensive place to dine out, with an average meal for two costing around $67. Garrett, the CEO of Discover New York, suggests, “October and June have gorgeous weather, so outdoor activities are a good choice, with sailing, in-depth neighborhood walks and biking.” For great value, she advises traveling in January and February, when the city offers tons of indoor activities, from art galleries and Broadway shows to indoor sports events and thousands of dining options.

    Sydney

    With its incredible surfing beaches, dining scene and friendly locals, Sydney is always a favorite of travelers. It's also expensive. Generally, the shoulder seasons (fall and spring in the U.S.) have the most comfortable weather and fewer crowds than the December-to-February high season. But some months have particular appeal, according to Stuart Rigg, Australian travel specialist for Southern Crossings. April, for example, falls into the low season, which means you'll find hotel deals along with weather that's typically “very pleasant,” Rigg says. “Sydney also has some great events during this low season period,” he adds.

    London

    Petulia Melideo, who runs Context's London walking tours, advises booking well in advance for lower hotel rates, and suggests a wintry visit. “November is a great time for London. The weather is still tolerable—and if it gets too chilly, there are plenty of cozy pubs to pop into,” she says. Other good times to visit include June, which means fewer tourists.

    How to fight California's wildfires? It's an “all of the above” respond.

There might, indeed, be a need to make it easier to thin dying or dead trees out of thickly forested areas, reducing the fuel for wildfires. But the problem is actually more complicated. Even if dead trees are removed, the dry bushes act like kindling (引火物) when wildfires spread.

    Even more to the point, thick forests were not a factor in these recent California's fires. “They're using these fires to talk about forest management that has nothing to do with the landscape in which the fires are occurring,” says Chur Miller. W. M. Keck Professor of Environmental Analysis and History at Pomona College in Claremont, California.

    Climate change is making wildfires worse. The resulting unpredictable weather patterns have created shorter, wetter winters in California, producing a sudden, heavy growth of brushes, grasses and trees. After winter, the state's ongoing drought and record- high summer temperatures draw water out of the plants, making them near-perfect kindling. With the hot and dry Santa Ana winds of fall, fires explode out of control.

    Yet these tragedies can't be blame only on global warming. Wildfires are actually a vital of the state's ecosystem. Lodgepole pines (松树), for example, grow well in fire-prone areas where millions of structures have been built in rural areas of California since the 1940s.When they bum, the cost in lives and treasures skyrockets.

Answering these disasters with a one-dimensional solution helps no one, although it might score short-term political points. The proper response includes placing limits on residential expansion into wildlands; better management and removal of dry brushes and continuously addressing the growing concern of climate changes.

    In other words, the solution isn't either/or. It's all of the above.

    After many considerations and years of heated argument, gray wolves were brought back to Yellowstone National Park. Fourteen wolves were caught in Canada and transported to the park. By last year, the Yellowstone wolf population had grown to more than 170 wolves.

    Gray wolves once were seen here and there in the Yellowstone area and much of the continental United States, but they were gradually displaced by human development. By the 1920s, wolves had practically disappeared from the Yellowstone area. They went farther north into the deep forests of Canada, where there were fewer humans around.

    The disappearance of the wolves had many unexpected results. Deer and elk populations — major food sources for the wolf — grew rapidly. These animals consumed large amounts of vegetation (植被), which reduced plant diversity in the park. In the absence of wolves, coyote populations also grew quickly. The coyotes killed a large percentage of the park's red foxes, and completely drove away the park's beavers.

    As early as 1966, biologists asked the government to consider reintroducing wolves to Yellowstone Park. They hoped that wolves would be able to control the elk and coyote problems. Many farmers opposed the plan because they feared that wolves would kill their farm animals or pets.

    The government spent nearly 30 years coming up with a plan to reintroduce the wolves. The U.S. Fish and Wildlife Service carefully monitors and manages the wolf packs in Yellowstone. Today, the debate continues over how well the gray wolf is fitting in at Yellowstone. Elk, deer, and coyote populations are down, while beavers and red foxes have made a comeback. The Yellowstone wolf project has been a valuable experiment to help biologists decide whether to reintroduce wolves to other parts of the country as well.

    Many of us know about Russia's Lake Baikal from our textbooks, or by listening to Chinese singer Li Jian's hit song, Lie Baikal. But over the past decade, the world's deepest freshwater lake has been in the spotlight for an extreme sport.

    Each March since 2005, about 150 people from around the world sign up for the Baikal Ice Marathon. They come to explore the lake's breathtaking beauty and challenge themselves in unpredictable conditions. The 26-mile (41.84-kilometers) journey starts on the lake's eastern shore. In March, the ice is a meter thick and iron-hard. Runners cross this frozen surface, finishing on the western side of the lake.

    Known as the "blue eye of Siberia", Lake Baikal has exceptionally clear waters. This means its ice is almost perfectly transparent (透明的). "Seen from above, a runner on the ice looks as if he or she were jogging through space." The New York Times noted.

    The landscape might be beautiful, but it's also harsh. Strong winds blast (侵袭) across the lake and frostbite can occur within half an hour. Runners say the cold climate is what draws them. They want to test their limits.

    "When you are in such an environment, you don't have cars around you, and you don't have the noise around. I think these extreme races allow you to be alone with nature." Alicja Barahona, a 64-year-old runner from the US, told ABC news.

    The location offers some strange and unique characteristics for this marathon. The finishing line is visible from the start, but the endless white offers no progress markers. The race also ends with little fanfare (隆重的欢迎). Tourists crowding the ice are mostly addicted to snapping selfies (自拍) and just ignore the runners.

    For some runners, the absence of spectators makes the race more challenging, because it's lonely. They must fight with themselves. "You are alone on Baikal. It is your race. You are alone with yourself. All you need to do is to defeat yourself." Veronique Messina, a French runner, told the Telegraph.

    Alison Malmon was trapping up (完成) the end of her freshman year at the University of Pennsylvania, US when she got the news: Her older brother Brian, a student at Columbia University, was suffering from mental illness.

    Inspired by this, Malmon formed a group at her university to empower (使能够) students to talk openly about mental health. It soon blossomed into a national organization that today has more than 450 campus chapters. Leaders with the organization spend their time talking with college students about the pressure that today's young people face.

    "What you hear often is just a need to be perfect," said Malmon, "and a need to present oneself as perfect."

    And a new study in the UK proved that this need for perfectionism is simply part of today's society. In the study, two researchers studied more than 40,000 students from the US, Canada, and the UK. They found that what they called "socially prescribed(社会定向型的) perfectionism" increased by a third between 1989 and 2016.

    Lead researcher Thomas Curran said that while so many of today's young people try to present a perfect appearance online, social media isn't the only reason behind this trend. Instead, he said, it may be driven by competition in modern society, meaning young people can't avoid being sorted and ranked in both education and employment. That comes from new norms(准则) like greater numbers of college students, standardized testing and parenting that increasingly emphasizes success in education.

    For example, in 1976, half of high school seniors expected to get a college degree of some kind. By 2008, more than 80 percent expected the same. The researchers also said changes in parenting styles over the last two decades might have had an impact. As parents feel increased pressure to raise successful children, they in turn pass their "achievement anxieties" onto their kids through "excessive(过多的) involvement in their child's routines, activities or emotions"

    Those in the mental health community like Malmon say they're concerned about the impact the culture of perfectionism has on mental health on campuses. "Mental health has truly become this generation's social justice issue," she said. "It's our job to equip them with the tools and to let people know that it's not their fault."