The World Health Organization says that the disease polio is no longer widespread in India. In 2009，half of the world's cases of polio were there. But In 2011, there was only one new case of polio in the country.

    Polio is caused by a virus. It spreads very quickly from one person to another. Victims often lose the use of their arms and legs. In the most serious cases, polio can kill a person.

    Twenty-five years ago, polio affected about 200, 000 children in India each year. The United Nations children's organization, UNICEF, sent teams of health workers into local villages. Team members told families in their neighborhood about the importance of giving liquid medicine to children to protect them against polio.

    But it was not easy at first. A member said, “They used to think that our children will not be able to have children when they grow up if they get the drop. They used to think like this. But now they don't. Now they allow their kids to get the drops.” Now things have changed. Asma Khatun is a mother in the town of Ghaziabad in the northern state of Utter Pradesh. She said, “Whenever anyone comes, we get the children vaccinated(接种疫苗). Even if nobody came to our house, we would send our children to a clinic to get vaccinated.

    A local Muslim leader says the vaccination campaign has been successful because it is supported by religious leaders. He said, “The polio vaccination campaign has been successful here because our Muslim scholars are with us.

    With their support, we are able to make people understand that giving children the vaccine is beneficial and crucial.”

    The Indian government has now launched a new campaign to vaccinate 170 million children under the age of five. The campaign will target newborn babies, migrants and people living in poor, crowded areas where the disease spreads more quickly.

    Of all nature's disasters, forest fires are often considered the most frightening. Moving at lightning speed, huge walls of flames can burn acres of land in just a few minutes. And although technology, including the use of fire-retardant chemicals, has greatly helped the fight against forest fires, they still do great damage.

    According to the National Interagency Fire Center, the fire season last year was the worst on record in terms of the number of fires and acres burned. There were 96. 385 fires and 9.873429 acres affected by fire in a year that was 125% more destructive(毁灭性的) than the10-year average. These fires cost the federal government $1.5 billion to fight, and this figure does not include the money spent by local and state governments as part of the effort.

    Fires in the southern states represented half of the national total last year with Texas, Oklahoma and Arkansas being home to a usually high amount of activity. Wildfire has also taken place in Western states such as California, Colorado and Alaska throughout the past 10 years.

    It is said that two-thirds of forest fires are started accidentally by people. Almost one quarter are purposely set, while lighting causes 10%.

    Forest fires can have advantageous effects. Charcoal(木炭) enriches soil and some plant species(种类) grow well after fire. The cones of the jack pine tree, for example, will not spread their seeds unless there is heat. Douglas fir trees grow best in open sunlight areas after fire.

    Obama, Lady Gaga and Steve Jobs—what do they have in common? They are, of course, all Americans. And according to a survey by social networking site baidu.com, they all best illustrate the word “cool”.

    But just what does it mean to say someone is “cool”? Most would answer that it is something to do with being independent-minded and not following the crowd.

    Yale University art professor Robert Farris Thompson says that the term “cool” goes back to 15th century West African philosophy. “Cool” relates to ideas of grace under pressure.

    “In Africa,” he writes, “coolness is a positive quality which combines calmness, silence, and life.”

    The modern idea of “cool” developed largely in the US in the period after World War II. “Post-war 'cool' was in part an expression of war-weariness… it went against the strict social rules of the time,” write sociologists Dick Pountain and David Robins in Cool Rules: Anatomy of an Attitude.

    But it was the American actor James Dean who became the symbol for “cool” in the hugely successful 1955 movie Rebel without a Cause. Dean plays a tough guy who disobeys his parents and the authorities. He always gets the girl, smokes cigarettes, wears a leather jacket and beats up bullies. In the movie, Dean showed what “cool” would mean to American young people for the next 60 years.

    Today the focus of “cool” has changed to athletics stars. Often in movies about schools, students gain popularity on the athletics field more than in the classroom. This can be seen quite clearly in movies like Varsity Blues and John Tucker Must Die.

But many teenagers also think being smart is cool. Chess and other thinking games have been becoming more popular in schools.

    “Call it the Harry Potterization of America—a time when being smart is the new cool,” writes journalist Joe Sunnen.

    A new study, conducted by British company Mindlab International, has found that listening to music at work increases accuracy (精确) and speed, The Telegraph reported.

    Perhaps, some parents disagree with this idea, saying, "Switch off the music and concentrate!" Well, if that's the case with your parents, you might now be able to convince them that you have science on your side.

    The company gave 26 participants （参与者）a series of different tasks for five days in a row, including spell checking, mathematical word problems, data entry, and abstract reasoning. The participants completed these tasks while listening to music or no music at all.

    The results showed that while music was playing, 88% of participants produced their most accurate test results and 81% completed their fastest work. David Lewis, chairman of Mindlab International, told The Telegraph, "Music is a very powerful management tool if you want to increase not only the efficiency of your workforce but also their emotional state, they are going to become more positive about the work."

    However, you may have a list of your favorite songs, but not all kinds of music match all homework. For maths or other subjects involving numbers or attention to detail, you should listen to classical music, the study found. In the study, pop music enabled participants to complete their tasks 58% faster than when listening to no music at all. If you are reviewing your English writing, pop music is the best choice, as it is the best kind for spell checking. It cut mistakes by 14%, compared to listening to no music. After finishing your homework, do you often take time to check your answers? Maybe, some dance music is suitable for you.

    The Eiffel Tower is very famous in France. It is visited by 7 million visitors a year. The Eiffel Tower was designed by Gustave Eiffel in the late 19th century. On Monday, March 31st, 2019, it turned 130.

    The look of the Eiffel Tower is greatly loved by people today, but things were different when the design was first shown to the public. Many French artists thought that the design was ugly. However, Eiffel did not change a thing. He believed that once it was completed, people in Paris and visitors around the world would love the tower. He was certainly right.

    The tower became popular with the public as soon as it opened on March 31st, 1889, two years after the construction began. Over 3,000 people came to look at this new tower and even made the effort to climb the 1,710 stairs to the top. The 984-foot-tall Chrysler Building in New York City beat it.

    Today, the tower houses a number of restaurants on its first and second levels. The third level has been turned into a vast platform (平台). From there visitors can see the entire city of Paris. While visitors are allowed to take the stairs to the first two levels, the platform can only be got to by taking the elevators.

    To ensure that the “Iron Lady” always looks good, the tower is cleaned and repainted every eight years. It's an effort that takes a team of 25 workers, an entire year. If you travel to Paris one day, don't miss it, the excellent achievement.

    According to a recent study, a new genetically modified rice can prevent infections of HIV, the virus responsible for the disease AIDS.

    The study reports the newly-developed rice produces proteins that attach directly to the HIV virus. This process prevents the virus from mixing with human cells. The scientists say it can remove the effect of the virus and block its spreading.

    The Joint United Nations Program on HIV/AIDS reports that worldwide, nearly 37 million people were living with HIV in 2017. The organization says the largest number of those are in developing countries. Nearly two-thirds of HIV cases are in Africa. Now there is no cure for HIV/AIDS though there have been developments in oral drug treatments to slow the progression of the disease.

    The new study predicts the rice-based method will lead to long-term use of the anti-HIV treatment across the developing world. Researchers said the "groundbreaking" discovery is "realistically the only way" that anti-HIV combination treatments can be produced at a cost low enough for the developing world.

    They say the easiest and most cost-effective way to use the rice will be to make it into a cream to be put on the skin. The HIV-fighting proteins can then enter the body through the skin. People all over the world could grow the rice and make the cream themselves. This would prevent the cost and travel required for many patients to receive treatments and medicine.

    The process of changing the genetic structure of food crops has been debated for some time. Critics of genetically engineered crops believe they can harm people. The scientific team says further testing is needed to ensure that the genetic engineering process does not produce any additional chemicals that could be dangerous to people.