Justin Bieber used to be an ordinary Canadian boy, but his life totally changed in 2008. With his great musical talent, this seventeen-year-old boy has become a superstar in the music industry.

    Justin Drew Bieber was born in 1994 in Stratford, Ontario and was raised by his single mother. Bieber learned to play musical instruments when he was very young. In 2007, he took part in a local singing competition in his hometown, and he did it just for fun. He never took singing lessons before but surprisingly he placed second in the competition. Then, with the help of his mother, he uploaded (上传) videos of him singing on a website and they successfully attracted the attention of thousands of viewers. His videos got popular through word of mouth and some of them have received up to 10,000,000 views.

    Justin Bieber would have never gotten a career in the music business without his videos. Scooter Braun, a former marketing executive (主管) of So So Def Recordings, had watched Bieber's videos and he was impressed by the boy's talent. Braun then contacted Bieber and he flew the boy into Atlanta seven months after the first video was posted. Bieber showed his talent in singing as well as his ability in playing musical instruments. He then got a record deal.

    In 2009, Justin Bieber released (发行) his first single “One Time” while he was recording the debut album (首张专辑). The single “One Time” tells a story about love. This song had success not only in Canada and the US, but also in the international market. Then he released his debut album “My World 2.0” in 2010 and the song “Baby” became the lead single. This album successfully entered the Top Ten Charts in seven countries. In June 2010, he started his first world tour in Hartford, Connecticut. One month later, he started recording his second album.

    When I left my bag on a train, I lost my most precious possession, a small framed photograph of my great grandparents, Emily and Gordon Baker. The frame was made of silver, with an elegant flower design in one corner. The photograph was taken in March 1939 0n their wedding day. Emily looked very happy, and Gordon looked rather a larmed.  A few months later, he was killed in action in North Africa. I received the photograph when my aunt Mabel died.

    I'm a student at Edinburgh University and I live in an old Edwardian house.  At the end of last term, I packed a large bag and a small bag and set off for London, where I was planning to catch the Eurostar train to Paris. Minutes after getting off the train at Kings Cross Station, I realized that I'd left the small bag in the overhead luggage rack. I ran back to the train, but it had already left the platform. www..com

    This all happened several months ago, and I had become resigned to the loss of my most precious possession. then last week, something extraordinary happened. I logged onto the site ~ eBay and looked for a silver photo frame and I found it ! The photo of my great grandparents was on eBay !

    I called the person who was advertising it.   He was a little suspicious(怀疑 )  at first, and told me that he had bought it from a stall at an antique market. After we talked for a while, he asked if there was any way I could prove it was mine. All I could think of was that the photo was taken in March 1939. He opened the frame and made sure that this date was written by hand on the back of the photograph.

    “It's definitely yours. " he said.  "Come and get it ! "

    Can exercise during childhood protect you against memory loss many decades later?Exercise early in life seems to have lifelong benefits for the brain,in rats at least.

    "This is an animal study,but it shows that physical activity at a young age is very important一not just for physical development,but for the whole lifelong track of cognitive（认知的）development during ageing,"says Martin Wojtowicz of the University of Toronto,Canada."In humans,it may delay the appearance of Alzheimer's symptoms（阿兹海默氏症）,possibly to the point of preventing them."

    Wojtowicz's team divided 80 young male rats into two equal groups,and placed running wheels in the cages of one group for a period of six weeks.Around four months later—when the rats had reached middle age—the team taught all the rats to connect an electric shock with being in a specific box.When placed in the box,they froze with fear.

    Two weeks later,the team tested the rats in three situations: exactly the same box in the same room,the same box with the room arranged differently,and a completely different box in a different room.

    The rats without access to a running wheel when they were young now froze the same percentage of times in each of these situations,suggesting they couldn't remember which one was dangerous.But those that had been able to run in their youth froze 40 to 50 percent less in both changed box settings.

    “The results suggest the amount of physical activity when we're young,at least for rats,has influence on brain and cognitive health—in the form of better memories—when we're older,"says Arthur Kramer of Northeastern University in Boston,who has found that,in humans,exercise promotes the growth of new brain cells.

    A medical study has shown that excess(过度的)coffee drinking could cause heart attacks in people who do not metabolize(使新陈代谢)caffeine fast enough.

    The study, published recently in the Journal of the American Medical Association, says an enzyme(酶)that metabolizes caffeine in the liver works differently in some people, depending on the make­up of the gene(基因). People who have a slow version (版本)of the enzyme are at a greater risk(风险)of a heart attack when they drink more coffee. The risk had something to do with a person's age and how many cups of coffee he drinks.

    The team from the University of Toronto in Canada studied 4,024 people living in coffee­rich Costa Rica between 1994 and 2004, of whom half suffered non­fatal(非致命的)heart attacks. They found slightly more than half had the slow version of the gene, while the rest had the fast form.

    Two to three cups of coffee a day increased the possibilities of a heart attack by 36 percent for those with the slow­acting gene and four or more cups a day lifted it by 64 percent.

    But those under 50 who had the fast version of the gene had a lower risk of heart disease, even with four or more cups a day.

    Those with the fast­acting gene who drank two to three cups of coffee a day had 22 percent reduced possibilities of having a heart attack, but drinking four or more cups a day only lessened the risk by 1 percent. Scientists recommend limiting coffee consumption(消耗量)to within four cups a day.

    When athletes at the 2020 Tokyo Olympics collect their medals, they'll not only be wearing something that celebrates their sporting performance, but something that symbolizes lastingness. For both the 2020 Olympics and Paralympics, organizers aim to make all of the gold, silver, and bronze medals out of used electronics. This strong message about how to make use of e-waste has gotten a lot of Japan involved.

    Starting in April 2017, the Japanese Olympic Committee began collecting old laptops, digital cameras, smartphones, and other abandoned electronics. The initiative (倡议) has achieved great success. Already, the quantity needed for bronze medals has been met, and they're in the homestretch for silver and gold medals, meaning the collection process can pack up at the end of March.

    When looking just at the number of cell phones collected, the amount of waste is shocking. In a period of about 18 months, a little over 5 million smartphones were collected thanks to cooperation with NTT DOCOMO. Japan's largest mobile phone operator allowed the public to turn in phones at their shops, which counted a lot in the project's success.

    After being taken apart and sorted, the small electronics underwent a smelting process to extract (提炼) all the gold, silver, and bronze elements. Thanks to this initiative, the worldwide struggle with e-waste will have a global platform. According to a study published by the United Nations University—44.7 million metric tons of e-waste were made in 2016. Only 20% of that was actually recycled. Unfortunately, this figure is set to rise significantly in the coming years, moving to 52.2 million metric tons by 2021. So while the Tokyo Olympics initiative might be just a drop in the bucket, it's a good start in showing what the public can do if they're made more aware of the issue.

    The fridge is considered necessary. It has been so since the 1960s when packaged food list appeared with the label: "Store in the refrigerator."

    In my fridge less Fifties childhood, I was fed well and healthy. The milkman came every day, the grocer, the butcher, the baker, and the ice-cream man delivered two or three times each w eek. The Sunday meat would last until Wednesday and the bread and milk left became all kinds of cakes. Nothing was wasted, and w e w ere never troubled by rotten food. Thirty years on, food deliveries have stopped, and fresh vegetables are almost impossible to get in the country.

    The invention of the fridge contributed comparatively little to the art of food preservation. Many well-tried techniques already existed — natural cooling, drying, smoking, salting, sugaring, bottling...

    What refrigeration did promote was marketing — marketing hardware and electricity, marketing soft drinks, marketing dead bodies of animals around the world in search of a good price.

    Consequently, most of the world's fridges are to be found, not in the tropics where they might prove useful, but in the rich countries with mild temperatures where they are climatically almost unnecessary. Every winter, millions of fridges hum (make a low continuous sound) away continuously, and at vast expense, busily maintaining an artificially-cooled space inside an artificially-heated house —while outside, nature provides the desired temperature free of charge.

    The fridge's effect upon the environment has been clear, while its contribution to human happiness has been unimportant. If you don't believe me, try it yourself, invest in a food cupboard and turn off your fridge next winter. You may miss the hamburgers, but at least you'll get rid of that terrible hum.