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.

    Scientists used to explore (探测) on the surface of the ocean. Now they are exploring below the surface, too. They want to know about ocean water and the plant and animal life deep in the ocean.

    In 1934 the scientist William Beebe dived 3000 feet below the surface in a hollow steel ball. In 1935 August Piccard dived 10330 feet In I960 his son Jean dived to a depth of 35800 feet. All these early dives were deep. But the divers could not stay down for very long. They had to come back up to the surface after a few seconds. Scientists needed to stay down longer to study life below surface. Gradually they succeeded. Cousteau, a Frenchman, was able to keep men down to a depth of 36 feet for one month and to a depth of 90 feet for a week.

    Now scientists are developing even better equipment. With this new equipment, men can stay below the surface for days or even weeks. In 1962 Cousteau set up a research station 35 feet below the surface. Then, in 1964, he set up another station on the ocean floor of the Red Sea. This was the first undersea station to operate without help from the surface.

    Many countries are now studying undersea living. The former Soviet Union has an undersea laboratory in the Crimean Sea. The United States has a laboratory 50 feet down on the ocean floor off the Virgin Islands. In 1970 five men lived there for two weeks. Then a team of five women scientists stayed in the laboratory. Next came other teams of men. All were there to explore the ocean depths and to make plans for the use of its resources. Scientists hope to find enough mineral, vegetable, and animal wealth there to provide food for the entire world.

    Do you want a pleasant holiday? The summer holidays are upon us again. Here is our guide to summer holiday fun in Peterborough!

    Peterborough Museum

    The Age of the Dinosaur is the museum's main attraction this summer. Get close to prehistoric creatures via some great hands-on exhibits! The museum is open from 10:00 a.m. to 5:00 p.m. Monday to Saturday, and from 12:00 p.m. to 4:00 p.m. on Sundays in August.

    Call 01733-864663 for details.

    Saxon Youth Club

    School holiday fun: Young people aged 13—19 will be able to produce their own music, compete in sports activities, or try their hand at cooking at Saxon Youth Club, Saxon Community Centre, Norman Road, Peterborough every Monday and Wednesday from 3:00 p.m. Plus an aeroball tournament will take place on Thursday,12th August between 3:30 p.m. and 6:30 p.m.

    Call 01353-720274 for details.

    Houghton Mill

    Alice Through the Looking Class—a new production of the family favorite on Monday, 30th August. Bring rugs or chairs to sit on and a picnic if you wish to eat during the play. Gates open 5:30 p.m., performance 6:30 p.m.—8:30 p.m. Tearoom will be open until the end of the interval. Adult￡ 10. Child ￡7. Family ￡20.

    Booking advisable on 0845-4505157.

    Farmland Museum and Denny Abbey

    Farmland Games: From Welly Wanging to Pretend Ploughing matches, come and join the Farmland Team. Collect your sporting stickers and create a colorful rosette that is fit for a winner! No need to book, just turn up between 12:00 p.m. and 4:00 p.m. on Thursday, 19th August. Suitable for children aged four and above, each child should be accompanied by an adult and all activities are included in the normal admission. Tickets Cost￡7 per child.

    For further information, call 01223-810080.

    On a Friday night, a poor young artist stood at the gate of the New York railway station, playing his violin. The music was so great that many people stopped to put some money into the hat of the young man.

    The next day, the young artist came to the same place, and put his hat on the ground gracefully. Different from the day before, he took out a large piece of paper and laid it under his hat. Then he began to play the violin. It sounded more pleasant than ever.

    Soon he was surrounded with people who were attracted by the words on that paper. It said, “Last night, a gentleman named George Sang put an important thing into my hat by mistake. Please come to claim (认领) it soon.”

    After about half an hour, a middle-aged man rushed through the crowd to the violinist and said, “Yes, it's you. I knew that you were an honest man and would certainly come here.” The young violinist asked calmly, “Are you Mr George Sang?” The man nodded. The violinist asked, “Did you lose something?”“It's a lottery ticket,” said the man. The violinist took out a lottery ticket on which George Sang's name was seen. “Is it?” he asked. George nodded and took the lottery ticket and kissed it, then danced with the violinist.

    The violinist was a student at an arts college and had planned to attend advanced studies in Vienna. Later his classmate asked the violinist, “At that time you needed money to pay the tuition and you had to play the violin in the railway station every day to make money. Why didn't you keep the lottery ticket for yourself?”

    The violinist said, “Although I don't have much money, I live happily. But if I lose honesty I won't be happy forever.” Through our lives, we can gain a lot and lose so much. But being honest should always be with us.

    China has become the first country to successfully land a spacecraft on the far side of the moon. The Chang'e-4 probe (探测器) has also made the first lunar landing since 1972. It has the task of exploring the side of the moon that never faces the earth. The dark side of the moon is older and has a thicker surface than the visible side. It takes the moon as long to go around on its own axis (轴) as it does for one complete orbit around the Earth.

    The Chinese probe landed in a huge crater 2500 km in diameter and 13 km deep. The crater is one of the oldest parts of the moon and our solar system.

    Scientists hope to learn more about the geology of the far side of the moon. The craft has two cameras on board which will send images back to earth. It will also attempt to send signals to distant regions of space, something that cannot happen on earth because of too much radio noise.

    Chang'e-4 also has instruments on board to examine minerals as well as a container with seeds which will try to create a miniature (微型的) biosphere (生物圈).

Communication with the spacecraft is not easy. Images and other data must be transmitted to a separate satellite because no direct communication with the earth is possible.

    For China the Chang'e-4 mission is an important achievement, because the country has successfully done something no other nation on earth has. It wants to become a leading power in space exploration and has announced plans to send astronauts to the moon and set up its own space station.

Top 4 Amusement Parks in the World

    It's summertime! That means parents have extra time to spend with their children, and what better way to engage in classic fun with family and friends than to visit an amusement park? Take a look at these fun choices — perfect summer trip ideas to fit every budget (预算).

    Cedar Point

    Tickets: $280 for adults, $120 for children

    Praising itself as the roller coaster capital of the world, Cedar Point's 18 coasters will ensure you're riding all day. Reader Alicia Goettemoeller describes the park as a "paradise for excited thrillers" while reader Nick Schuyler says it is "built for grown-up kids."

    Knoebels

    Tickets: $120 for adults, $10 for children

    This old-fashioned amusement park is a must for your old memory games as well as money saving - admittance and parking are free of charge. Reader Tracy Ginsburg Maier says "a family of 4 can enjoy special offer to eat, swim and ride all day for $100" at Knoebels.

    Kings Island

    Tickets: $340 for adults, $160 for children

    Kings Island is one of the most visited theme parks in the US, with more than 3 million visitors per year. The park is especially known for its family-friendly attractions, such as Snoopy Island. Tickets to the main park also include admission to the nearby water park, Boomerang Bay.

    Dells Water Parks

    Tickets: $140 for adults, $80 for children

Wisconsin Dells is a water park with dozens of indoor and outdoor water parks to spread around in. One of them, Noah's Ark, is the largest outdoor water park in the US. Many are open year-round and no charge for children under five.