On Monday, the Centers for Disease Control and Prevention predicted that 42% of Americans could be overweight by 2030. Our expanding waistlines lead to not only a medical problem, but according to a recent article In The New York Times, it could also endanger personal safety in some situations—in an airplane crash, for example.

    The New York Times' Christen Negroni reports that engineers and scientists are questioning whether airplane seats are adequately constructed to protect overweight travelers. Government standards for airplane seat strength（强度）— first set moe than 60 years ago — require that the seats be made for a passenger weighing 170 pounds (77kg). Today, the average American man weighs nearly 194 pounds (88kg) and the average woman 165 pounds (75kg). Negroni reports:

    “If a heavier person completely fills seat, the seat is not likely to behave as intended during a crash,” said Robert Salazar, the leading scientist at the Center for Applied Biomechanics at the University of Virginia. “The energy absorption that is built into the aircraft seat is likely to be overpowered and the passengers will not be protected properly.”

    “Nor would the injury be limited to that passenger only,” Dr. Salzar said. “If a seat or a seat belt fails,” he said, “those people who are seated nearby could be endangered from 'the uncontrolled movements of the passenger'.”

    Most complaints about airplane seats focus on their lack of comfort and high ticket price, and whether overweight passengers should be made to buy two seats. But The New York Times' article brings up another reason to feel anxious about flying. Investigators of the issue got in touch with the airplane seat and seat belt makers, but they refused to comment on the problem. Experts agreed that crash testing should be done with overweight dummies （人体模型）. Both airplane seats and seat belts should be tested, they said.

    Fortunately, however, according to Nora Marshall, a senior adviser at the National Transportation Safety Board, the board's investigators have never seen an accident involving a commercial plane in which the weight of a passenger was a problem.

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    We all have different ways to navigate (导航) when lost—whether asking a stranger for help, consulting an old-school map or simply following our nose. But on a bike, the risks are higher. One wrong turn or that you're in a traffic jam with two lanes between your bike and the nearest pavement may ruin your good mood. Although cyclists, of course, managed to navigate before smart phones, cyclists can make two choices: a few stay calm and embrace getting lost, and the rest turn to a navigation app.

    Google Maps added a directions function for cyclists in 2015 in the US and Canada, and two years later across Europe. And while there are dozens of other apps now offering a similar service, Google Maps has the demerits for many, so the app seems to be falling behind expectations.

    As someone with no sense of direction, I knew it wouldn't be easy when I started cycling earlier this year. I appreciated that the app gave me two warnings before I needed to turn off a road, and automatically recalculated my route if I accidentally went off course. But still, it wasn't a smooth process. Google Maps thought I could cut across a double carriageway with no breaks in its barrier, assumed I knew what it meant when it told me to “head west”, and thought nothing of taking me the wrong way down a busy one-way street.

    Cyclists don't just want safety—they want convenience. Londoner Robson Smith regularly cycles between Clap ham and the City of London and would like to see Google Maps calculate routes where his bike is allowed on public transport and more choice of the type of routes he can take. “Google tends to calculate the most common and comfortable cycle routes. It would be better to have an option which included the fastest route, regardless of comfort,” he says.

    For this reason, Robson says he uses the app Cycle Streets instead. It offers a choice of four different route modes, based on the type the user wants, and saves previous routes. It also tells you how many calories a route burns, how many traffic lights you wilt encounter, and how busy it is.

    Based on new analysis, we are rapidly approaching major climate change and the effects on society and the environment could be quite severe. Geographers predict that within the next eighty years, current world climate zones could shift and some could completely disappear. Polar regions will get colder while tropical regions will get even hotter, forcing animals to migrate  (迁徙) north.

    Climate changes like these could lead to the spread of diseases. Tropical storms and hurricanes will not only increase but may also become more intense. If the changes come too quickly, animal and plant species may not be able to adapt fast enough and could disappear.

    According to Science Daily, a new study predicts that by the year 2100, many of today's familiar climates will be replaced by climates unknown in today's world. It is urgent that we reduce the risks of these far-reaching consequences for the whole world. The planet itself has been showing signs of change. In 2004, a serious tsunami created by a major earthquake killed thousands in Sumatra and in 2008, thousands died in China because of another severe earthquake. Egypt was hit in 2009 with a major earthquake and Haiti was devastated in 2010 by yet another massive earthquake.

    Within just the last few months, new reports from around the world have been coming in and most agree that our climate situation is much worse than previously thought. At this point, it doesn't matter what is causing it, but rather, what can be done about it. What's more, our world is getting more and more unstable every year. There is war and threat of war everywhere. Natural disasters are becoming more frequent and serious.

    However, other planets are experiencing global warming as well as our own and some scientists believe there may be some connection between this. No one knows anything for sure at this point because there is simply not enough data.

    All Poetry, the largest poetry writing group, would improve poets' works, create a fan base, and read the best poetry of our generation. It is the home base for poets. Many poets are willing to show their works and over 500,000 poets get feedback（反馈）and improve their poetry. Both beginners and experts are welcomed. All Poetry helps poets learn what they need to improve.

    Writing groups

    All Poetry is designed as a big writing group. Every poem gets several .encouraging comments. We also have private comments for friends.

    Award-winning poets

    The best poems are featured, and many poets have won national contests. Experts encourage amateurs（业余爱好者）to improve their poems.

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    All contests are totally free and some are with cash prizes. Dozens of free contests are started every day. Let fair judging inspire you.

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     “All Poetry has helped me improve my work so much! I'm now so much more confident about my use of concrete images, and other poetic devices. My own poetry is well received and appreciated and that makes me very happy.”

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    “As a member, I've made some good friends at All Poetry. I really appreciate the exchange of constructive comments and general contact with some excellent writers of poetry.”

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What Is Social Media?

    Not many people ask the question “what is social media?” anymore. Social media has been around for years now, and most of us would probably describe it as any Internet medium that can be used to share information with others, including blogs, forums, applications, games, websites and other stuff.

    But let me ask you this: what exactly is so “social” about sitting before a computer setting up a blog and blogging for days without anybody reading it, or scrolling through your Facebook feed of information from 500 friends you barely know? If you ask me, it can be way more anti-social than anything.

    Social media is not a “thing”. It's not just Facebook, WeChat and Weibo It's more of a frame of mind and a state of being. It's about how you use it to improve your relationships with other people in real life. However, we tend to rely on technology and social media so much that it can actually tear apart those relationships.

    Social media isn't about numbers. When someone says “social media,” web giants like Facebook, Twitter, WeChat and Weibo instantly pop into our minds, often because they have more updates, more friends, more followers, more links, more photos, more everything. We tend to get distracted by the number game, thinking “volume, volume, volume”. It's led to a lot of meaningless noise and information overload. As the old saying goes, quality over quantity is usually the way to go. So, social media is not just about lots of people aimlessly pushing around lots of information.

    Social media needs to have an “IRL” factor-an Internet slang standing for “In Real Life”. It should affect how a person thinks or acts offline. After all, social media shouldn't be an end in itself. It was built to enhance your actual social life, in real life. Take for example an event that a person attends because they are invited by the host on Facebook through a Facebook event page. Something like that definitely has the IRL factor. Likewise, a WeChat photo that touches someone so much that they feel the need to bring it up and describe it to someone else during a dinner date also has the IRL factor.

    So, is it really considered to be social to spend an hour scrolling through photos on Weibo, with no thoughtful or emotional effect and no interaction with others? In fact, there is no wall between real life and Internet life where true social media exists. Social media is not a specific place on the Internet or just a thing you use to see what other people are doing. It's all about creating meaningful experiences and relationships wherever you may be.

    With its snow-covered mountains and a variety of wildlife, Yellow Stone National Park is one of the scenic treasures of the United States. Located primarily in Wyoming, the park hosts millions of visitors every year. If you plan to travel within the park, keep in mind advice from the National Park Service.

    Seasonal Travel

    Travel varies vastly from season to season. Roads are generally open in the summer except for cases of rock or mud slides, wild fires, accidents or road construction. Early snows in the fall can cause some roads to close temporarily. In the winter almost all roads are closed to motor vehicles, but snowmobiles and other snow vehicles with tracks are allowed. Roads begin to open for the spring by the latter part of April but can close if snowfall continues.

    Driving Time

    Grand Loop is the main road through Yellowstone National Park; it passes by most of the major attractions. These include Old Faithful, Yellowstone Lake and the Grand Canyon of Yellowstone. The maximum speed limit on the Grand Loop is 45 miles per hour, but the speed limit drops during some of the winding and twisting sections of this narrow road. Allow yourself at least two days to fully travel the loop due to the size of the park and being sometimes stuck in heavy traffic.

    Safety Awareness

    Buffalo(水牛)often block the roads in the park as they move through the fields. If a group is traveling across the road you are on  you can either wait for them to pass or find an alternative route. If you get out of your vehicle, the National Park Service says to stay at least 25 yards from any buffalo (and 100 yards or more away from bears and wolves). Buffalo are particularly unpredictable and charge people at speeds up to 30 mph.

    You can take your bicycle on any public roads and routes designed for bikes, but bicycles are not allowed on the park roads which are narrow with few shoulders. Altitudes range from 5, 300 to 8, 860 feet. The National Park Service recommends cyclists wear helmets and noticeable clothing.