Houses fall down. Trees fall over. Large holes form in the ground. Could Alaska be sinking? That's what some villagers in Alaska have been asking themselves recently and scientists think they know why. Warmer temperatures may be causing Alaska's frozen ground to thaw (解冻).

    About 85 percent of Alaska's land surface has permafrost (永久冻结带). Permafrost supports the ground above it—including trees, houses, and roads. But why is the permafrost thawing?

    Some scientists say that human-caused pollution is leading to global warming. And most scientists agree that Alaska has been getting warmer. They say that the warmer temperature is causing permafrost to thaw in some areas. The thawing permafrost can cause problems for people, plants, and animals.

    The collapsing (倒塌) is a problem in the villages in Alaska which are built on permafrost, and some of them may have to move to safer ground, where there is no permafrost.

    The Alaskan town of Glennallen saw its old post office collapse. And, according to James Walters, a permafrost expert at the University of Northern Iowa, house-moving companies have been very busy.

    “Melting permafrost can also destroy trees and forests,” Walters said. “When holes in the ground form, trees fall into them and die. This could turn a forest into a swamp (沼泽), and animals which need the forests will have to move elsewhere.”

    “The melting could cause severe problems.” Walters says, “This could take hundreds of years, but in the end Alaska will look quite different from what it looks like now.”

    Soft winds blew throughout the Windy City today. We welcomed the winds, as it was another hot day in Chicago. The wind blew, bringing us some coolness and making the weather not that hot. But it was a beautiful summer day with a blue sky.

    Chicago is a great city for eating, and we have enjoyed tasting the different foods. Last night, we tried one of the city's most famous foods: deep-dish pizza. Chicago claims credit for the rich and cheesy thick-crust pizza, covered with a sweet tomato sauce. We topped it with olives and green peppers.

    We were touring the city, mainly looking for delicious local foods. Today, we enjoyed a Polish specialty at lunch: Pierogis, an Eastern European dumpling-like dish, filled with foods like potatoes, cheese, mushrooms, cabbage and meat. Polish immigrants started settling in Chicago in the 1850s, and the city has one of the largest Polish communities in the U.S.

    We took a break from exploring the city to talk with some of you! Ashley and Caty logged onto the Internet for an on-the-road version of TALK2US. We spoke to an English teacher in Tokyo, Japan, and a graduate student in India.

    Meanwhile, Adam searched for some locations around the city to shoot some video. He chose a spectacular spot: Navy Pier, Chicago's most-visited attraction. The winds from Lake Michigan keep visitors cool, and the view of the Chicago skyline never fails to impress. In fact, the view made all of us head over heels!

    Our time in Chicago has come to an end. Tomorrow, the true journey begins, as we pass through Illinois and into Missouri via Route 66. Springfield, the home of Abe Lincoln, and St. Louis, the "gateway to the West," wait for us.

Music

    Opera at Music Hall: 1243 Elm Street. The season runs June through August, with additional performances in March and September. The Opera honors Enjoy the Arts membership discounts. Phone: 241-2742. http://www. cityopera.com.

    Chamber Orchestra: The orchestra plays at Memorial Hall at 1406 Elm Street, which offers several concerts from March through June. Call 723-1182 for more information. http://www.chamberorch.com.

    Symphony Orchestra: At Music Hall and Riverbend. For ticket sales, call 381-3300. Regular season runs September through May at Music Hall and in summer at Riverbend. http://symphony.org/home.asp

    College Conservatory of Music (CCM): Performances are on the main campus (校园) of the university, usually at Patricia Cobbett Theater. CCM organizes a variety of events, including performances by the well-known LaSalle Quartet, CCM's Philharmonic Orchestra, and various groups of musicians presenting Baroque through modern music. Students with I.D. cards can attend the events for free. A free schedule of events for each term is available by calling the box office at 556-4183. http://www.ccm.uc.edu/events/calendar.

    Riverbend Music Theater: 6295 Kellogg Ave. Large outdoor theater with the closest seats under cover (price difference). Big name shows all summer long! Phone: 232-6220. http://www.riverbendmusic.com.

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    Last year DeepMind's AlphaGo programme took on and beat two of the world's best players of the Chinese game of Go（围棋）-an unbelievable achievement seen as a milestone in the development of artificial intelligence (A). That programme was trained by first giving it vast amounts of data from amateur and professional games.

    The new AlphaGo Zero began with a blank board and nothing but the rules of Go and set about playing against itself. Within three days it was so advanced that it took on the previous version, which had taken months to develop, and defeated it by a hundred games to zero.

    DeepMind says that creating knowledge from first principles without learning from human expertise（专门技能）is an important step in developing artificial intelligence. The company's founder Demis Hassabis said this breakthrough could help in real world problems such as designing new drugs or discovering new materials.

    In 1997, Garry Kasparov was defeated by Deep Blue, a computer program written by IBM, running on a supercomputer. This was the first time that a ruling world chess champion was defeated by a computer program in tournament conditions. Superficially, AlphaGo's win against Lee Sedol can be compared to Deep Blue's win against Gary Kasparov, which happened almost 20 years ago. So: what's the big deal? We have to understand the differences between chess and Go.

    In chess, each player begins with 16 pieces of six different types. Each piece of type moves differently. The goal of the game is to seize the other player's king. Go starts with an empty board. The goal of the game is to gain as much territory（领地）as possible.

    Although the rules of Go might appear simpler than those of chess, the complexity of Go is higher. Also, games usually last longer for lots of moves. A typical game in Go might last for 150 moves vs.80 in chess.

    When men get together, they seldom talk about their feelings or inner thoughts. However, they talk about a lot, like their newest computer, how to repair their car, or even business.

    Talk might move to the best place to find fish or women, jump to computer games, then continue to the sport of the season. They also like to tell jokes each other and spend a fair amount of time playing one-up and boasting (吹牛). Men seldom call each other to chat.

    When man meets woman, he usually wants to make a good impression. Many single men try hard to carry on amusing, fun, and pleasant conversations. They use conversation to discover her interests and feelings in order to learn how to be attractive to her.

    Some men, either out of nervousness or ignorance, spend most of the time talking about themselves, often appearing to show off their achievements or talk endlessly about their problems or work. Even the quietest man talks to his woman when love is new.

    When women get together, they talk about feelings and relationships, their work and their family. They enjoy talking but also want the give and take of talk, then listen. Women often call each other to chat. Conversation is an important part of most women's lives.

    As relationships progress, however, many a man turns on the television and forgets how to talk. This raises anger and cry from his woman partner who says, “You never talk to me anymore.” Some men start talking. Many, however, mainly discuss their own achievements and problems.

    When the woman starts talking about her favorite subjects: feelings, family, relationships, friends and her work, many men lose interest or bring the conversation back to themselves. Pretty soon, the man is back to staring at the television each night, wondering where his relationship has gone. The woman is talking to her friends, mom, sister, or neighbor, often about that very relationship and how she is hurting.

    In 2015, a man named Nigel Richards memorized 386, 000 words in the entire French Scrabble Dictionary in just nine weeks. However, he does not speak French. Richards' impressive feat is a useful example to show how artificial intelligence works—real AI. Both of Richard and AI take in massive amounts of data to achieve goals with unlimited memory and superman accuracy in a certain field.

    The potential applications for AI are extremely exciting. Because AI can outperform humans at routine tasks—provided the task is in one field with a lot of data—it is technically capable of replacing hundreds of millions of white and blue collar jobs in the next 15 years or so.

    But not every job will be replaced by AI. In fact  four types of jobs are not at risk at all. First, there are creative jobs. AI needs to be given a goal to optimize. It cannot invent, like scientists, novelists and artists can. Second, the complex, strategic jobs—executives, diplomats, economists — go well beyond the AI limitation of single-field and Big Data. Then there are the as-yet-unknown jobs that will be created by AI.

    Are you worried that these three types of jobs won't employ as many people as AI will replace? Not to worry, as the fourth type is much larger: jobs where emotions are needed, such as teachers, nannies and doctors. These jobs require compassion, trust and sympathy—which AI does not have. And even if AI tried to fake it, nobody would want a robot telling them they have cancer, or a robot to babysit their children.

    So there will still be jobs in the age of AI. The key then must be retraining the workforce so people can do them. This must be the responsibility not just of the government, which can provide funds, but also of corporations and those who benefit most.