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    Have you ever wondered why the roots of the plants always know which way to grow—into the soil but not above it? Some British scientists have recently solved this mystery.    

      It turns out that roots have special hairs that tie them into the soil and help them grow their way past obstacles, a team at the John Inners Center in Norwich reports in the February 29 issue of Journal Science.

    "The key is in the fuzzy(有绒毛的) coat of hairs on the roots of plants," says professor Liam Dolan. "We have found a growth control system that enables these hairs to find their way and to become longer when their path is clear."

    Root hairs explore the soil in much the same way a person would feel their way in the dark. If they come across an obstacle, they make their way around until they can continue growing in an opening. I the meantime, the plant is held in place as the hairs grip the soil.

    The hairs are guided by a clever chemical trick. A protein(蛋白质) at the tip of the root hairs called RHD2 helps them to take calcium(钙) from the soil. Calcium makes the hairs grow, and produce more RHD2, and take more calcium.

    But when an obstacle blocks the hair's path, or the hair reaches the surface of the soil, the cycle is broken and growth starts in another direction.

    This system gives plants the flexibility to explore a complex environment and to live in even the most unpromising soils, says Dolan.

    In poor soils such as in parts of Australia and Africa, native plants have adapted by producing enormous numbers of root hairs. A better understanding of this adaptation will allow scientists to develop hairy rooted crops that can grow in unfriendly environments.

    According to Dolan, "Research in the John Inners Center is taking a breeding approach(育种方法) to increase hair length in wheat but it will be some time before new cultivars(栽培变种) are developed."

    A girl became a volunteer in the activities of Deathbed Care, which meant visiting and taking care of a patient suffering from an incurable disease with days numbered.

    The girl was assigned to look after an old man suffering from cancer whose children lived abroad. Their living conditions were not satisfactory while the old man had a lot of savings. She was expected to comfort him and keep up his spirits.

    Every Saturday the girl came on time to keep him company, telling him stories. When he was having an intravenous drip (静脉滴注), she would help massage his arms. The doctor found the patient much improved mentally. The old man began to involve himself actively in the medical treatment and he seldom shouted at others.

    But something that happened made the doctor uneasy and puzzled. Each time the girl left, the old man would give her some money. The doctor did nothing to interfere (干涉), unwilling to offend the old man. A month later the old man showed evident signs of decline after suffering coma (昏迷) a few times.

    When rescued from the latest coma, the old man told the doctor his last wish, “I have deep sympathy for the girl. Will you be kind enough to help her finish her studies？”

    But the doctor knew that her family was well­off and she had no difficulty pursuing her studies.  Sometimes she even came to the hospital in her father's car.

    When the girl came at the weekend after the death of the old man, the doctor told her the bad news. She was very sad and burst into tears. Then she handed $ 500 to the doctor, saying, “The old man had all along thought I came to do the job because of poverty. He gave me money so that I could continue my schooling.” Now he got the answer to the puzzle. In the last period of his life, the old man found it a real pleasure to be able to help a girl badly in need.

    It was the day after Halloween when my grandmother was admitted to the hospital with the worst headache she'd ever had. While posing in our costumes the night before, we knew something was wrong, just not how wrong.

    Grandma's house was the central gathering place of my family. Sunday lunches, birthday dinners, Easter, Thanksgiving, and Christmas — all were our traditions, with her as hostess. While my parents were busy running their small business, there were many nights when Grandma fed me and put me to bed in her spare room, until they came to get me. I spent my summers at Grandma's and I went everywhere with her. I couldn't imagine a time when she wouldn't be around me.

    Then November 1,1991 began her month-long stay in the hospital—she suffered from a rare infection (感染)called nocardia asteroides. After being born in the year of the Great Depression, living through World War II, raising three kids, and being widowed at the age of 48, Grandma never expected to live into her seventies. The infection in her brain seemed to confirm that she wasn't long for this world. But that's not the end of her story. A team of doctors successfully removed the abscess(脓肿), and Grandma even made it into a local medical journal. Her doctor called her “the brain lady”.

    Grandma celebrated her 85^th birthday in March this year. In the almost 23 years since her recovery, she's seen two of her four grandchildren get married and welcomed three great-grandsons. Although they damage something in her house, she loves it when my two boys come over. And while I know they make her day, seeing her love blossom for another generation makes my day too. Happy Grandparents' Day to my amazing grandmother!

    Sometimes it can be easy to become too satisfied when it comes to living sustainably. We may all have recycling bins in our kitchens, but here are some ways you can live more sustainably.

    ⒈Put an end to plastic water bottles and one-off coffee cups

    The only way this is going to work is that if you have reusable options you really love, invest in a great water bottle. This is an advance payment, but it will save you money in the long run. A 750ml bottle of Evian costs 90p in Tesco, meaning if you buy one every two days you could save £10 within three weeks by filling up a reusable bottle at home.

    ⒉_______________________________________

    The high street is problematic on so many different levels. Not only are you buying items with questionable supply chains, but the carbon footprint of each product is shocking as well. Online shopping is even worse, with overpackaging for each item and the emissions from delivery trucks. The answer is to stick to reach-me-down or previously owned items as much as possible. Not only will this save you money, but there's also a sense of satisfaction in finding a hidden treasure from the flea market where you find outstanding bargains or something used, which you simply can't get from shopping in Wal-Mart or on Amazon.

    ⒊Think hard about your transportation

    Even if your car is supposedly a low-emissions model, it's still going to be a huge contribution to your carbon footprint. There are times when getting in a car can't be avoided, but if you can substitute just one flight a year with a train, one car journey a week with a bus, and one bus a month with a bike ride, you'll find that making more mindful transport decisions can easily make your day-to-day life more environmentally friendly with little effort.

    ⒋Try to buy local, seasonal produce

    You may think buying strawberries in December or courgettes in spring is no big deal, but the chemicals and fuel used to artificially copy the right environment for them to grow create harmful gas emissions. Similarly, the environmental impact of transporting produce from another country is huge. Buying from local farmers also means you can often ignore the huge amounts of packaging the supermarkets use.

The Kids' Farm

    While kids visit vegetable plots and animal contact areas, they will learn that most of the food we eat every day comes from farms, and that taking care of animals takes time, commitment and knowledge.

    Kids can see our cows, donkeys, goats, alpacas, pigs, etc. and learn all about looking after farm animals. At the Caring Corral, they will have a chance to touch cows and donkeys, under staff members' supervision.

    Please Note:

    ●Any time you touch an animal, there is a risk of spreading germs (细菌). Visitors to the Kids' Farm should wash their hands after touching the animals.

    ●The Caring Corral is open only when the staff are available; hours are limited.

    ●The Kids' Farm uses pizza to teach kids how many kinds of food grow. Hands-on exhibits show how pizza ingredients go from the farm to the pizza. The Pizza Garden has slice-shaped plots of growing ingredients, including tomatoes, wheat and herbs.

    ●The 22-foot-wide Giant Pizza gives kids a place to play with oversized toppings and each other.

    ● During the busier season (beginning in June), a free shuttle picks up visitors in need of a lift at the Kids' Farm and drops them off at the Panda Plaza/the Bus Lot from 11 a. m. to 6 p.m.

    Auctions(拍卖行) are everywhere. Here are just a few standouts and some of the areas they specialize in. All have brick-and-mortar(实体的) sales rooms in addition to online buying.

    Leslie Hindman Auctioneers

    Headquarters(总部): Chicago

    Founded: 1982

    Best bets: contemporary art, jewelry

    The founder, Leslie Hindman, has been on an expansion kick from her Chicago base and now runs eight offices across the country. Ms. Hindman said that plenty of items sell at her house for around $500. As in the auction world generally, jewelry and contemporary art receive lots of attention from bidders(出价者), and in2017 a diamond ring sold for $97,000.

    Swann Auction Galleries

    Headquarters: New York

    Founded: 1941

    Best bets: books, works on paper, African-American art

    Founded as a rare-book auctioneer, Swann still holds dozens of such sales a year. The president, Nicholas D. Lowry, noted that Swann was the first auction house to sell old photographs, in 1952.The house has also had a department of African-American art for 12 years.

    Stair Galleries

    Headquarters: Hudson, N.Y.

    Founded: 2001

    Best bets: English and Continental furniture and paintings, modern and contemporary art

    Colin Stair, the founder and president, comes from a long line of antiques dealers (商人). Stair is frequented by dealers and bargain hunters, and it's a place to find interesting things like a George I carved walnut wing armchair, coming up as part of a sale on April 28 and 29.

    Heritage Auctions

    Headquarters: Dallas

    Founded: 1983

    Best bets: coins, sports memorabilia, movie posters

    With roots in coin auctions, Heritage has grown quite large. But their bread and butter are items that the company president, Greg Rohan, calls "the kinds of things that everyone has." "People aren't buying what were selling for decoration or for resale," he added. "They're buying things they absolutely love."