Disposing (处理) of waste has been a problem since humans started producing it. As more and more people choose to live close together in cities，the waste disposal problem becomes increasingly difficult.

    During the eighteenth century，it was usual for several neighboring towns to get together to select a faraway spot as a dump site. People would transport household rubbish，rotted wood and old possessions to the site. Regularly some of the trash was burned and the rest was buried. The unpleasant sights and smells caused no problem because nobody lived close by. Factories and some other industrial sites also had waste to be disposed of. Those located on rivers often just poured the unwanted remains into the water. Others built huge burners with chimneys to deal with the problem.

    Several facts make these choices unacceptable to modern society. The first problem is space. Dumps(垃圾场)， are most needed in heavily populated areas. Such areas rarely have empty land suitable. Farm areas are refusing to accept rubbish from elsewhere，cheap land in major city areas to dispose wastes is nonexistent(不存在的). Awareness of pollution dangers has resulted in more strict rules of waste disposal. Pollution of rivers，ground water，land and air is a price people can no longer pay to get rid of waste. The amount of waste，however， continues to grow.

    Recycling efforts have become commonplace，and many towns require their people to take part. Even the most efficient recycling programs，however，can hope to deal with only about 50 percent of a city's reusable waste，so more people should be involved in recycling programs.

    The number of accidents involving pedestrians (行人) wearing headphones is on the rise, a report suggests, causing fresh warning from road safety groups in Britain.

    A US-based study found a total of 116 reports of death or injury to pedestrians wearing headphones between 2004 and 2011, jumping from 16 in 2005 to 47 in 2011.

    Most victims were men (68%) and under the age of 30 (67%), with around one in ten of all cases (9%) under the age of 18.Some 89% of the cases occurred in urban areas and more than half (55%) of the victims were struck by trains .

Eighty-one of the 116 accidents (70%) resulted in the person's death—even though a warning was sounded in around a third of the cases.

    The study concluded, “The use of headphone may be a safety risk to pedestrians , especially in environments with moving vehicles（cars）. Further research is needed to determine if and how headphone use threatens pedestrian safety.” British road safety groups warned pedestrians to be careful.

    Floor Lieshout, director of Youth For Road Safety, said,“ This study shows once more the importance of using all of our senses while we are near traffic. It is important that we find an attractive way to make youth learn about the risks of wearing headphones in traffic.”

    Andrew Howard, who is the head of road safety at the Automobile Association, added that some pedestrians can be “so focused in their own little world they forget the world going on around them”. That can include headphone wearers, Howard said, but also people talking on phones.

    However, Howard said that more researches needed to be done.

    Earlier studies have shown that people wearing headphones or talking on phones can suffer “inattentional blindness” which makes them isolated (孤立) from the world around them .

    Ian Harvey, at the charity Civic Voice, said that “ to defeat isolation and to help build a civic(文明的) society, people need to interact(交往) with each other .

    He said,“ A basis for any civilized society is communication—Surfing the web, listening to MP3s, reading blogs or sending e-mail is not interacting with a person; it's interacting with a machine.

    “If people feel socially isolated, they need to have more face-to-face interactions with other human beings and in time, will begin to feel happier and more connected to the world and place they live in.”

    Maybe it has been the influence of the current scene: the type among urban biking. Apparently, urban biking requires entirely different bikes than suburban hiking does and therefore a Bike Design Project started where five design studios across five cities had to come up with a perfect urban bike. The winning bike will be manufactured for a limited run of 100 hikes and will be in stores next year. Industry, a Portland-based studio, came up with a very interesting bike: one that uses bluetooth and handlebars (车把手) that tell you when to stop or turn.

    Industry worked together with Ti Cycles to create a bike with a 3D printed titanium frame (钛框架). The hike is called Solid and can be connected to a smartphone APP: My Bike. This APP alarms a user when a light needs replacement and if something gets wrong with one's brakes. There is also software called Discover My City, which has a series of routes through Portland's most trendy neighborhoods, with suggestions about where to eat and shop.

    Nevertheless, the idea with cycling is that you need to focus on the road and not on your smartphone. This bike therefore uses integrated feedback on handlebars. Those handlebars tell a user when to turn, as they will buzz when a turn appears. As you are getting closer, they will buzz more frequently. And then there is the possibility to control your light via built-in sensors and change gears by pressing an electronic button.

    Although the bicycle looks highly interesting and can be seen as a piece of art for the designing world, we don't know if we would like our bike to have an automatic buzz when we are approaching a turn. On the other side, it could add some extra safety to traffic in general. Whether you like the bike or not, you have to admit the Portland-based studio brings the concept of urban biking to a whole new level.

    Have you ever run into a careless cell phone user on the street? Perhaps they were busy talking, texting or checking updates on WeChat without looking at what was going on around them. As the number of this new “species” of human has kept rising, they have been given a new name — phubbers（低头族）.

    Recently, a cartoon created by students from China Central Academy of Fine Arts put this group of people under the spotlight. In the short film, phubbers with various social identities bury themselves in their phones. A doctor plays with his cell phone while letting his patient die, a pretty woman takes selfie（自拍照）in front of a car accident site, and a father loses his child without knowing about it while using his mobile phone. A chain of similar events eventually leads to the destruction of the world.

    Although the ending sounds overstated, the damage phubbing can bring is real. Your health is the first to bear the effect and result of it. “Constantly bending your head to check your cell phone could damage your neck,” Guangming Daily quoted doctors as saying. “the neck is like a rope that breaks after long-term stretching.” Also, staring at cell phones for long periods of time will damage your eyesight gradually, according to the report.

    But that's not all. Being a phubber could also damage your social skills and drive you away from your friends and family. At reunions with family or friends, many people tend to stick to their cell phones while others are chatting happily with each other and this creates a strange atmosphere, Qilu Evening News reported.

    It can also cost you your life. There have been lots of reports on phubbers who fell to their death, suffered accidents, and were robbed of their cell phones in broad daylight.

I will never forget the year 1979. I was just ten years old when my father decided to take me to see a stunt (特技) show starring the famous motorcyclist, Evel Knievel. After seeing the amazing stunts, I started dreaming about riding bikes and performing stunts myself one day.

My whole childhood was spent at skate parks; there was a group of us that would go there every day after school with our BMX bikes (a type of bicycle designed to ride on rough ground). After all, I would need to get some practice if I was going to be like my hero!

My later teenage years were spent competing in endless BMX freestyling championships; some I won and others I lost. But it was never about the trophies (奖杯). The atmosphere was magical, with over 1,000 riders at some events. I just loved the rush of energy I got from this, and from continuously trying newer, more daring stunts.

In 1995, I was chosen to compete in an important international action sports competition. For once in my life I was nervous. I landed badly on my hand and got injured. It took me out of the sport for a while, but my attitude was: "If others have suffered more and gone on, then why can't I?" I had once read that Evel Knievel suffered a total of thirty­five broken bones.

When the International Olympic Committee made BMX an Olympic sport, I couldn't have been more delighted! The way I see it, the sport finally got the recognition it deserved. Its entry into the Olympics encourages more people to take it up seriously.

I have heard some people say that BMX is too dangerous for kids. The risks, though, are really no greater than, say skateboarding. With riders pushing the limits far beyond what I could ever have imagined when I first started riding professionally, BMX seems set to remain one of the most exciting sports in history.

People who routinely eat a lot of red meat may be increasing their risk of developing Type 2 diabetes （糖尿病）, according to a new study. Processed red meats, like bacon and hot dogs, are linked to an even higher risk.

Researchers tracked the eating habits of more than 200,000 people engaged in long-term health studies for up to 36 years and found that those who regularly consumed a lot of red meat — more than a serving per day — had a significantly higher risk of developing Type 2 diabetes.

"When we looked at the women and men who consumed the most red meat compared to the least, we found about a 50% increase in risk," says study author Dr. Walter Willett of the Harvard T. H. Chan School of Public Health. The results were published in The American Journal of Clinical Nutrition.

It turned out that the participants in the study who consumed high amounts of red meat also had higher body weight. They consumed more calories （热量） and were less physically active compared with those who consumed the least red meat.

Given that, in the US, only about 4% of people are identified as vegetarians and only 1%vegans, it's not realistic to think that people will give up red meat altogether. So how much red meat is OK to consume? US dietary guidelines don't clearly state an amount, but a recent review of observational studies suggests it's reasonable to limit daily consumption of unprocessed red meat to 50 to 100 grams to prevent high blood pressure and heart diseases. Willett's recommendation goes even further. "A limit of one serving per week of red meat would be reasonable for people wishing to improve health and well-being," Willett says.

Given the large body of evidence that links too much red meat consumption to increased risks of heart disease and cancer, Christopher Gardner, a food scientist at Stanford University, points out that recommendations to limit the consumption of red meat, particularly processed red meat, have been made by many national and global health organizations.