Bats are the only mammals(哺乳动物) that can fly a great distance, but they have another ability. Many bats live a very long time for an animal of their size. European researchers are studying bats to understand why they lives0 long. They hope to make discoveries aimed at fighting the aging process in human beings.

    Last week, the group of scientists said they had identified important biological qualities in some bat species. The group studied bat chromosomes(染色体), a line of genes found in the nucleus(细胞核) of cells. The scientists were most interested in structures connected to the ends of the chromosomes. They are called telomeres(端粒), which protect the ends of chromosomes and shorten each time a cell divides. Scientists believe this shortening process causes cells to breakdown. They say this is what causes aging.

    The European researchers studied 493 bats from four bat species. The group used information that had been gathered over more than 60 years. Of these animals ，the greater mouse-eared bat generally lived the longest, an average of 37 years. The scientists said this and a related species, which are grouped together under the name Myotis, had telomeres that did not shorten with age. Another Myotis bat holds the record for oldest age, reaching 41years. The scientists' findings suggest that these bats cells have the ability to maintain and repair their telomeres. This, they said, helps guard against the aging process.

    Based on its body size, a bat like the greater mouse-eared bat would be expected to live four years. But, these mammals have been found to live nearly 10 times longer than that. The scientists found that only 19 species of mammals live longer than humans when their body size is considered. Eighteen of these are bats.

    About 5,000 children die each day due to preventable diseases such as cholera and dysentery (痢疾) , which spread when people use unclean water for drinking or cooking. A lack of water for personal health leads to the spread of totally preventable diseases like trachoma, which has blinded some six million people.

    Water troubles also trap many low-income families in a cycle of poverty and poor education and the poorest suffer most from lack of access to water. People who spend much of their time on ill health, caring for sick children, or collecting water at distances averaging 3.75 miles a day don't have educational and economic opportunities to better their lives.

    Agriculture is called the lion's share of freshwater worldwide, using some 70 percent, and industrial uses consume another 22 percent. Water areas have no political borders and nations don't always work together to share common resources, so water can be a frequent source of international conflict as well.

    Day-by-day demand keeps growing, further needing water sources, from great rivers to groundwater. “We're going deeper into debt on our groundwater use,” Postel said, “and that has very significant impacts on global water security. The rate of groundwater consumption has doubled since 1960.”

    Some of Earth's groundwater is fossil water created when Earth's climate was far different. Today such water is as limited as petrol. “But we're pumping much of them out faster than ever,” Postel explained. “Humanity's growing thirst also causes a major problem about water and our ecosystems. And that also creates a cost to us, to our sons and to our grandsons, not just to nature.”

    Every year, millions of people head to London's Trafalgar Square to see Nelson's Column, and the four lion statues that “guard” it. And last month, during the London Design Festival, a bright red lion sculpture was added to the collection.

    But this was more than just a statue: It had a large open mouth, with an LED screen inside it. At the same time, passersby could type in random words on a screen close to the lion, which were used to produce an AI-created poem. The most interesting part of the poems lies in their randomness, as the words that people choose to enter include many things, such as the time, the weather and their mood. In the daytime, the finished poem appeared on the LED screen, but at night, it was projected (投射) onto the lion's body and the famous Nelson's Column, in a 1ovely light display.

    Es Devlin, the sculpture's creator, was inspired by the history behind the four historic lion statues. Edwin Landseer, the designer of the lions, wanted them to look much more animated, but Queen Victoria refused his plan. This made Devlin wonder, "What if we could give a lion a poetic voice?" According to Devlin, although England has seen many poems about national identity in recent years, these works have been lacking imagination. "I wanted to make a piece that was poetic and collective" he told BBC News.

    After standing for almost 180 years, the purpose of Trafalgar Square has changed over the years. But thanks to the high-tech lion and its poetry, the square is standing the test of time.

    There was a lot of news related to artificial intelligence, or AI, and machine learning. Among the stories were two dealing with direct competitions between humans and machines.

    In one competition, machines that used AI performed better than human beings in a high-level reading test. Two natural language processing tools beat human in the experiment. One of the tools was built by the American technology company Microsoft. The other was created by Chinese online seller Alibaba Group.

    In another competition, a computer took on humans in live, public debates.

    The event demonstrated how AI-powered computers are increasingly being developed to think ' and sound like humans. The organizer of the debates, U. S. technology company IBM, announced split results. It said a majority of those watching said they felt the machine had done more to improve their knowledge of the subject. But, the human got more praise for communicating their ideas.

    This year, we also explored the many ways AI and machine learning are now being used. For example, some U. S. judges use machine learning systems to help them decide when, and for how long, criminals should be jailed. The system uses computers to examine data from thousands of court cases.

    One fast-growing area of AI is facial recognition, which is increasingly being used for security purposes. Recently, Atlanta's Hartsfield-Jackson airport became the first in the U. S. to permit passengers to use facial recognition technology to get on flights. A Chinese company showed off an AI system it developed to recognize individuals by body shape and walking movements. The system is already being used by Chinese police in Beijing and Shanghai.

    In addition, machine learning was used during 2018 to predict results of the World Cup soccer competition. The technology also created artwork that sold for a large amount of money. And it is being used to help farmer save time and money, while reducing environment-harming chemicals. Other technology systems are being used to follow farm animals and wildlife to collect information on their activities.

    Once upon a time, there was a little boy who wanted to meet the king. He set off, walking towards the king's castle. After many years of walking, the king's castle came into his view. However, as the boy drew closer to the outside of the castle, the guards took notice of him.

    "Get out of here!" commanded the guards.

    Well, the little boy didn't have to be told twice. He turned...and ran right away. All he wanted to do was to tell the king wonderful things, and see all the beautiful things in the king's house. But he couldn't even get near the castle! The boy finally stopped running, sat down and cried.

    A young man happened to be coming down the path at the very moment. He saw the little boy and came up. "What's wrong, young man?" he asked.

    "Sir, I walked and walked just to see the king. But these guards made me frightened. I wanted to tell the king how lovely everything is and just tell the king that I just wanted to see him!"

    The man looked at the little boy thoughtfully. "Look, why don't you try again. Don't lose heart. I'll come with you this time."

    The little boy got up and took the man's hand. The king's guards spotted them.

    "Look, mister, we don't have to do this...I don't want you to get hurt. We can just turn around now."

    The man held the little boy's hand and went on. The boy really thought the man might be crazy until he looked back up at the guards. They were all smiling now. The little boy was surprised.

    "Who are you?" asked the little boy in surprise.

    "Why, I'm the king's son. You can enter the castle and be with the king," said the man.

    The little boy broke into a huge smile.

    A new study has found the amount of antibiotics(抗生素)given to farm animals is expected to increase by two-thirds over the next 15 years. Researchers are linking the growing dependence on the drugs to the increasing need for meat, milk and eggs. However, the drugs could quicken the development of antibiotic-resistant infections(感染). Such infections are already a major public, health concern in the United States.

    The World Health Organization notes when people stop living in poverty(贫困), the first thing they want to do is eat better, rather than earn more money. For most people, that means their diet should contain more meat. With the rapid development of Asia, people there are eating nearly four times as much meat, milk and other milk products as they did 50 year ago.

    To meet the need, farmers have put many animals into smaller spaces. As the animals are crowded together, the easiest way to deal with some of the problems of crowding is to give them antibiotics. It's clear that antibiotics help animals stay healthy in a crowded environment and grow faster. But bacteria can develop resistance to the drugs gradually.

    Nowadays, doctors find antibiotics that once worked against the infections no longer work. The bacteria have learned ways to fight against the drugs. The heavy use of antibiotics in animals is responsible for the growth of antibiotic resistance worldwide. In the United States, at least two million people get drug-resistant infections each year and at least 23,000 die from an infection.

    Europe has banned the use of antibiotics to increase animal growth. And the United States is hoping to persuade farmers to stop using antibiotics for that purpose.