Recently, South Korean star PSY's “Gangnam style” video has been popular on the Internet. It has become most people's favorite music.

In fact, the song has set the Guinness World Record for the most popular video in the history of the Internet. More than two million people have said “like” since the song was on the Internet on July 15.

    PSY's special dance moves and funny horse riding style have attracted many people. Although many people do not understand the language, the video has become the talk of the Internet. The song has come to first place in the music charts in 31 countries, including the United States, the United Kingdom, and Canada.

    “I just sang for my South Korean fans. I have never expected it to be popular in other countries,” PSY told the reporters on a concert. The song was so popular that a few of South Korean's politicians showed PSY's moves to attract supporters.

    “The song came out in mid-July. It sings about the rich life of South Korea--especially Gangnam in Seoul, where a lot of rich people live.

    Millions of people have watched the video. Many stars, such as Katy Perry, Robbie Williams and Nelly Furtado said that they love the song. These stars performed part of the song at a recent concert.

    Riding high on the success of “Gangnam Style”, PSY was signed by Scooter Braun to Braun's Schoolboy Records, a label distributed by Universal Republic.

    PSY has written many hit songs of varying styles for different singers. Prior to “Gangnam Style” his most famous composition perhaps was Lee Seung Gi's debut(首次亮相) song “Because You Are My Woman”.

    In its early history, Chicago had floods frequently, especially in the spring, making the streets so muddy that people, horses, and carts got stuck. An old joke that was popular at the time went something like this: A man is stuck up to his waist in a muddy Chicago street. Asked if he needs help, he replies,“No, thanks. I've got a good horse under me.”

    The city planners decided to build an underground drainage(排水) system, but there simply wasn't enough difference between the height of the ground level and the water level. The only two options were to lower the Chicago River or raise the city.

    An engineer named Ellis Chesbrough convinced the city that it had no choice but to build the pipes above ground and then cover them with dirt. This raised the level of the city's streets by as much as 12 feet.

    This of course created a new problem: dirt practically buried the first floors of every building in Chicago. Building owners were faced with a choice: either change the first floors of their buildings into basements, and the second stories into main floors, or hoist the entire bulidings to meet the new street level. Small wood-frame buildings could be lifted fairly easily. But what about large, heavy structures like the Tremont Hotel, which was a six-story brick building?

    That's where George Pullman came in. He had developed some house-moving skills successfully. To lift a big structure like Tremont Hotel, Pullman would place thousands of jackscrews(螺旋千斤顶) beneath the building's foundation. One man was assigned to operate each section of roughly 10 jackscrews. At Pullman's signal each man turned his jackscrew the same amount at the same time, thereby raising the building slowly and evenly. Astonishingly, the Tremont Hotel stayed open during the entire operation, and many of its guests didn't even notice anything was happening.

    Some people like to say that every problem has a solution. But in Chicago's early history, every engineering solution seemed to create a new problem. Now that Chicago's waste water was draining efficiently into the Chicago River, the city's next step was to clean the polluted river.

    Exposing living tissue to subfreezing temperatures for long can cause permanent damage. Microscopic ice crystals (结晶体) cut cells and seize moisture (潮气), making donor organs unsuitable for transplantation. Thus, organs can be made cold for only a few hours ahead of a procedure. But a set of lasting new antifreeze compounds (化合物)—similar to those found in particularly hardy (耐寒的) animals—could lengthen organs' shelf life.

    Scientists at the University of Warwick in England were inspired by proteins in some species of Arctic fish, wood frogs and other organisms that prevent blood from freezing, allowing them to flourish in extreme cold. Previous research had shown these natural antifreeze molecules (分子) could preserve rat hearts at -1.3 degrees Celsius for up to 24 hours. But these proteins are expensive to extract (提取) and highly poisonous to some species. “For a long time everyone assumed you had to make synthetic (人造的) alternatives that looked exactly like antifreeze proteins to solve this problem, ”says Matthew Gibson, a chemist at Warwick who co-authored the new research. “But we found that you can design new molecules that function like antifreeze proteins but do not necessarily look like them.”

    Most natural antifreeze molecules have a mixture of regions that either attract or repel water. Scientists do not know exactly how this process prevents ice crystal formation, but Gibson thinks it might throw water molecules into push-pull chaos that prevents them from tuning into ice. To copy this mechanism, he and his colleagues synthesized spiral-shaped molecules that were mostly water-repellent—but had iron atoms at their centers that made them hydrophilic, or water-loving. The resulting compounds were surprisingly effective at stopping ice crystals from forming. Some were also harmless to the roundworm Caenorhabditis elegans, indicating they might be safe for other animals.

    “These compounds are really cool because they are not proteins—they are other types of molecules that nonetheless can do at least part of what natural antifreeze proteins do, ”says Clara do Amaral, a biologist at Mount St. Joseph University, who was not involved in the research. Gibson's antifreeze compounds will still need to be tested in humans, however, and may be only part of a solution. “We don't have the whole picture yet,”do Amaral adds. “It's not just one magical compound that helps freeze-tolerant organisms survive. It's a whole suite of adaptations.

    How do you get a man to do his share of the housework? If you are like most women, you've faced this question the hard way.

    A man will enjoy a clean, orderly house, but he usually won't make the effort to clean or organise it. This doesn't mean that a woman has to do all the housework; she may have to manage many of the household duties, and request her partner's participation(参与). A woman can often say that men and women should take equal responsibility(责任) for housework.

    Very few men are raised to be fully responsible for housework, and many men look on housework as women's work. On the other hand, most men will readily work around the yard, make repairs and complete projects on weekends or evenings, and it's important that you give your man appreciation(欣赏) for those things, too. Most men will take on a little housework around the house if asked politely. They are even more likely to do housework if they can choose what they want to do, and do it without being monitored(监视).

    Here's the key: men want to feel that they are doing housework either because they want to do a task, or because they simply want to please their women. Men are much less likely to take on household tasks they consider uninteresting and unimportant. In other words, men are likely to do a household task just for the good of the house.

    When I was in the eighth grade, one caring teacher of mine taught me several useful little techniques. He told me to keep a notebook nearby when I was reading and that I should try to figure out what the main idea of every paragraph was so that I could understand the passages better. It seemed awfully boring at that time, but I decided to give it a try anyway.

    It didn't take long before I started reading a book called How to Read a Book that would completely change how I thought about the written word. Thanks to these techniques, I learned to get the most out of reading. I kept applying them over the years until I finally came up with a lot of little techniques for reading a book.

    I also eventually came to learn that there were a lot of different kinds of reading. For example, when I read a Stephen King novel, the interesting plot made me completely relaxed. Then there's reading to learn new things, which is what I do when I read personal finance books. There's also reading to understand and grow, which is easily the hardest and the most rewarding. The last kind of reading involves taking a piece of literature or a nonfiction book that you might read for simple pleasure and transforming it into something life-changing, or something that causes you to question some of your deeply-held ideas and beliefs.

    How to Read a Book really focuses on the latter two: books that you read to learn about a new topic or to learn a skill, and books that you read to learn about yourself. If you've ever been drawn to read to really improve yourself, this book is well worth the time to read even if it's a bit dry at times. Let's dig in.

    War can be deadly for wildlife, too. A new study reports that war is the biggest threat to Africa's elephants, rhinoceroses, and other animals. Researchers examined how years of conflict in Africa have affected populations of large animals. More than 70 percent of Africa's protected wildlife areas have been within a war zone at some point in the last 70 years. The more frequent the fighting, the greater the drop in animal populations, said Josh Daskin, an ecologist at Yale University. He was the lead author of the study, which was published Wednesday in the journal Nature.

    It takes very little conflict, as much as one conflict in about 20 years, for the average wildlife population to be declining, Daskin said. "Areas with frequent fighting — but not necessarily the bloodiest fighting—lose 35 percent of their large animal populations during each year of war," he said.

Some animals get killed by weapons of war. Yet, many also die because of changes in social and economic conditions in an area as a result of war, said Rob Pringle. He is an ecologist at Princeton University and the study's co-author. "People in and around war zones are poor and hungrier. So they may begin to illegally hunt animals for valuable tusks or hunt protected animals to eat," Pringle said. "And during wartime, animal conservation programs do not have as much money or power to protect wildlife."

    The new study examined the entire African continent over 65 years. The researchers looked at 10 different factors that could change population numbers. They included war, drought, animal size, protected areas and human population density. The number of wars had the biggest effect on wildlife population. The intensity of the wars — measured in the number of human deaths — had the least effect on animals.