Can people change their skin color without suffering like pop king Michael Jackson? Perhaps yes. Scientists have found the gene that determines skin color.

    The gene comes in two versions, one of which is found in 99 percent of Europeans. The other is found in 93 to 100 percent of Africans, researchers at Pennsylvania State University report in the latest issue of Science.

    Scientists have changed the color of a dark-striped zebra-fish（斑马鱼） to uniform gold by inserting a version of the pigment (色素) gene into a young fish. As with humans, zebra-fish skin color is determined by pigment cells, which contain melanin (黑色素). The number, size and darkness of melanin per pigment cell determine skin color.

    It appears that, like the golden zebra-fish, light-skinned Europeans also have a mutation (变异) in the gene for melanin production. This results in less pigmented skin.

    However, Keith Cheng, leader of the research team, points out that the mutation is different in human and zebra-fish genes.

    Humans acquired dark skin in Africa about 1.5 million years ago to protect bodies from ultra-violet rays of the sun (太阳光紫外线), which can cause skin cancer.

    But when modern humans leave Africa to live in northern latitudes, they need more sunlight on their skin to produce vitamin D. So the related gene changes, according to Cheng.

    Asians have the same version of the gene as Africans, so they probably acquired their light skin through the action of some other gene that affects skin color, said Cheng.

    The new discovery could lead to medical treatments for skin cancer. It also could lead to research into ways to change skin color without damaging it like chemical treatment did on Michael Jackson.

    Music is an international language. The songs that are sung or played by instruments are beautiful to all people everywhere.

    Popular music in America is what every student likes. Students carry small radios with earphones and listen to music before class, after class and at lunch. Students with cars buy large speakers and play the music loudly as they drive on the street.

    Adult drivers listen to music on the car radio as they drive to work. They also listen to the news about sports, the weather, politics, and activities of the American people. But most of the radio broadcast is music.

    Pop or popular music singers make much money. They make a CD or tape which radio stations use in every state. Once the popular singer is heard throughout the country, young people buy his or her tapes. Some of the money from these tapes comes to the singer. Wherever the singer goes, all the young people want to meet him or her. Now the singer has become a national star.

    Besides pop music, there are two other kinds of music that is important to Americans. One is called folk music. It tells stories about the common life of Americans. The other is called western or country music. This was started by cowboys who would sing at night to the cows they were watching. Today, any music about country life and the love between a country boy and his girl is called western or country music.

    Smartphones, tablets and laptops make it easy for people to work on the go, but traditionally, printers have been cumbersome to move out of the office. However, the new Zuta Pocket Printer will enable people to print anywhere. The Zuta Pocket Printer was invented by Zuta Labs, based in Jerusalem. This small printer is about 10.2 cm wide and long and 7.5 cm high, and weighs about 350 grams. The company plans to ship its printers to customers in the beginning of 2017.

    This printer can connect wirelessly to smart phones, tablets, laptops and PCs via Wi-Fi, and is supported by Android, iOS, OS X and Windows. A free application from the company lets you use the printer via a mobile appliance; a laptop or PC can also select the printer for Use just like any other wirelessly connected printer. This printer can print one average A4 page, measuring 21 by 29.7 cm. Zuta Labs noted that its printer can print on any standard size piece of paper, and that, in principle, it could print on any surface.

    The printer's," omni-wheels" help it turn and move in any direction on a surface. Laser sensors（激光传感器）help control the movement, speed and location, according to the company.

    Zuta Labs said the printer's rechargeable battery can last about l hour, on average—long enough to print about 60 pages. One ink cartridge（墨盒）can print more than 100 pages, according to the company. Currently, the appliance prints only in black, although Zuta Labs said it plans to have a full-color printer in the future.

For your next out-of-this-world vacation, you now have the option of literally going out of this world—-but it'll cost you $ 40 million. Then again, can you really put a price tag on having the time of your life? According to a new report from Popular Mechanics, Russia is looking to build a luxury hotel in outer space. There you will wake up to a breathtaking blue planet—--the earth! The hotel is expected to be stationed on the International Space Station (ISS).

While space tourism itself isn't exactly a novel idea, the notion of building a hotel out there hasn't been raised before. Really, other companies are still focused on the transportation part of the puzzle—-after all, a trip to space is enough for most folks.

    According to Popular Mechanics, the hotel will include a luxury orbital suite with big windows, personal hygiene(卫生) facilities, exercise equipment, and yes, WiFi. Because if you can't share your experience on social media, did it really even happen?

    Of course, the reasons behind the hotel aren't just for fun and games. Apparently, space tourism might be able to help the Russians pay for another module to add to the International Space Station. Russian space contractor RKK Energia is currently building the first such module, which will give scientists a laboratory and power supply station from which to conduct tests.

    If any of this is going to happen, however, Russia is going to have to hurry. With the ISS expected to be out of use in 2028, there's little time to build the hotel and find wealthy tourists to actually buy a trip into outer space.

    So if you've recently come into a fortune and are interested in what could be the time of your life, ISS is calling your name.

    Artificial intelligence can predict when patients with a heart disorder will die, according to scientists.

    The software learned to analyze blood tests and scans of beating hearts to spot signs that the organ was about to fail. The team, from the UK's Medical Research Council, said the technology could save lives by finding patients that need more aggressive treatment. The results were published in the Journal of Radiology.

    According to the researchers, high blood pressure in the lungs damages part of the heart, and about a third of patients die within five years after being diagnosed. There are treatments: drugs, injections straight into the blood vessels, a lung transplant. But doctors need to have an idea of how long patients might have left, in order to pick the right treatment.

    The software was given scans of 256 patients' hearts, and blood test results. When this data was combined with eight years of patient health records, the artificial intelligence predicted when patients would die.

    The software could look about five years into the future. It correctly predicted those who would still be alive after one year about 80% of the time. The figure for doctors is 60%.

    The team now want to test the software works in other patients in different hospitals before assessing whether it should be made widely available to doctors. The researchers also want to use the technology in other forms of heart failure, such as cardiomyopathy, to see who might need a pacemaker or other forms of treatment.

    Dr Mike Knapton, from the British Heart Foundation, said, "This exciting use of computer software in medical practice will help doctors in the future to make sure that patients are receiving the correct treatment before the condition deteriorates and leaves them needing a lung transplant. The next step is to test this technology in more hospitals with heart disease."

The Big Ben is located in the tower at the eastern end of the Houses of Parliament, Westminster, Greater London. It was designed by Edmund Beckett and Baron Grimthorpe.

The Big Ben is very famous throughout the world, but nobody really knows why it is called Big Ben. There are two hearsays about this. Some people say that it was named after Benjamin Caunt, a boxer, who was called Big Ben. More people believe it was called after Welshman, Sir Benjamin Hall. He was the commissioner(特派员)of the work at the time of its installation in 1859. A story was told that during a debate in the Commons on what to call the bell, Sir Benjamin was about to give his ideas when a MP who sat behind the front bench shouted, "Let's call it Big Ben!" Then this name came into being.

The bell hasn't gone through a smooth road since the beginning of its design. Because there was great disagreement about the design of the clock. It took fifteen years to build. In 1857, the bell was completed and tested on the ground, but a four-foot crack appeared and the bell had to be cast again. Finally, the clock started ticking on 31 May, 1859, and struck its first chime(报时)on 11, July. Then in September, the bell cracked again. It was silent for four years but was eventually turned a quarter of a revolution(旋转). In this way, the crack was not under the striking hammer. Craftsmen made a square above the crack to stop it growing longer and it can still be seen today.

The Big Ben is famous not only for its 13-ton weight, but also for its accuracy(准确性) which is a result of its precise mechanism(机械装置). Even one extra penny's weight on the balance will cause a gain of two fifths of a second in twenty-four hours. Although there have been several problems, the bell is still striking today. Its chimes can be heard all over the world on the B. B. C.