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We tend to think of memory as unique to animals. But it isn’t. Plants also have a form of memory. Yes: they, too, are shaped by what happens to them, and alter their responses to future events based on their experiences in the past.For example, like all plants, wild tobacco, (also called Nicotiana sylvestris) can’t move to escape from its enenfies--the caterpillars (毛虫) and other animals that enjoy eating its leaves. It can, however, act to stop them. It can detect damaged leaves; in response, it produces nicotine. The nicotine travels from the roots, through the sap (树液) and into the leaves~ Nicotine apparently doesn’t taste good: caterpillars fed on leaves from plants that recently experienced damage--and so are high in nicotine--eat much less than caterpillars fed on leaves from previously undamaged plants.But here’s the interesting part. Tobacco plants attacked for the first time take longer to mount their defense than tobacco plants that have previously experienced an attack. This isn’t because the previously attacked plants keep on producing a higher level of nicotine--they don’t. Nicotine is expensive for a plant to make, so they only do it when necessary. And plants that have been attacked twice are faster to respond than plants that have only been damaged once. Somehow, they remember.The physical basis of plant memory is still being figured out. Of course trees don’t have conscious memory. But by now it’s clear that wild tobacco is not the only plant with the capacity for memory, nor is caterpillar attack the only stress that produces such an effect. Drought, cold and altered salt levels in the soil all do so; likewise, exposure to bacteria.If plants remember-can they also forget As far as I can tell, no one knows the answer to this yet. Nor does anyone know how many different kinds of stresses a plant can keep track of at once. But the subject is important, as the stresses plants are exposed to can affect how well they grow. Being able to prime them to respond to pests, or enable them to forget about a drought, could have big implications for agriculture. Wild tobacco can detect damaged leaves and （） in reaction to prevent caterpillars from eating its leaves.
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No one word demonstrated the shift in corporations’ attention in the mid-1990s from processes to people more vividly than the single word "talent". (62) the word lies the idea that more and more corporate (63) .is going to be created by knowledge and by so-called "knowledge workers". (64) labour is worth less; knowledge is worth more.This has significantly shifted the balance of power in the (65) process. Companies used to be (66) about finding enough qualified people to run their operations. What they could not fmd they would train, was the (67) attitude. That might take some time, but in a world where people sought jobs for life time was in the company’s (68) But talent is not patient, and it is not faithful. Many companies found themselves training employees (69) for them to go on and sell their acquired skills to their (70) So now they look for talent that is ready-made.In their eagerness to (71) this talent, companies have gone to considerable lengths to appear especially attractive. They have, (72) , devoted (奉献) a great deal of effort to the design of their websites, often the first (73) of call these days for bright young (74) recruits. They have in many cases (75) their HR departments, in part so that they can (76) their remuneration (报酬 ) packages more finely for the individuals that they really require. And they have altered their approach to issues such as governance and environmental responsibility (77) they know that many of the talented people they are seeking want to work for ethical and (78) employers.Talented people increasingly want to work in places where they can feel good about what they do for most of the day. What’s more, in today’s knowledge-based businesses, these young people are far more (79) of their working environment, of "what’s going on around here", than were their grandparents. It is harder for today’s businesses to (80) from their employees what they are (81) to--even when, as in cases such as Euron and WorldCom, they put a lot of effort into it. 64（）
Let’s face it--there are lots of reasons to hate McDonald’s: calories, cholesterol and, for me at least, that sickening feeling after munching (大口咀嚼) on McNuggets. Then there’s always that kid at the drive-through who forgets the ketchup (番茄酱).Well, add one more reason to spite McDonald’s: as the global economy spirals downward, McDonald’s is minting money. "In the worst of times for the restaurant industry, it’s the best of times for McDonald’s," says Butt Flickinger Ig, managing director of the Strategic Resources Group, a retail-consulting company. In fact, the company’s sales have increased for 55 straight months. Profits grew 11% to $1.2 billion.The pricing of McDonald’s, highlighted by dollar-menu items like apple pies, side salads and yogurt, plus cheap combo meals is a key strength during the recession. In particular, consumers are fleeing casual, family chain restaurants for the convenience and savings of fast food.The economy is not the only reason people are drawn to McDonald’s. T, he company’s management also deserves credit for its success. Back seven years ago, America’s obesity (肥胖) epidemic was a hot topic, and McDonald’s suffered from the strong negative reaction. Stale food and tired stores also kept people away. "McDonald’s was actively persuading customers from coming back," says John Glass, a Morgan Stanley analyst.Since that time, McDonald’s have remodeled 11,000 stores. At a neat and clean restaurant in the Bronx one weekday evening, Brian Waters, a mailman, sat with his 9-year-old son in a booth. The bright dining area featured abstract paintings of New York City’s bridges and the Statue of Liberty. "It used to be dark and dull in here," Waters says. "Now it’s nice and clean. I don’t mind sitting here anymore." Stores have also extended hours: 34% of the company’s 14,000 U.S. restaurants are now open 24/7.The menu got an upgrade too. Obscene "super-size" choices were phased out, and healthier options like apples and salads were added. The company changed its coffee blend; coffee sales have soared 70% over the past two years. Chicken McNuggets nov( consist solely of white meat, which has less fat and fewer calories than the darker-meat mix of old.Like any other business in this environment, McDonald’s faces some potential roadblocks. As the recession wears on, fast-food-service growth may flatten out; plus, McDonald’s can expect more price competition. For exanlple, Steak ’n Shake, the diner-style burger chain in 21 states throughout the Midwest and South, is promoting four different meal combos for less than $4. "In Los Angeles, every other billboard is a 99-cent food price," says Glass. The battle for bargain-hunting eaters is on. But given its recent winning ways, McDonald’s might just add a few more billion served. In what way does Steak ’n Shake constitute the greatest challenge to McDonald’s（）
Several years ago I was teaching a course on the philosophical assumptions and cultural impact of massive multi-user online games at Williams College. The students in the course were very intelligent and obviously interested in the topic.But as the semester progressed, I began to detect a problem with the class. The students were working hard and performing well but there was no energy in our discussions and no passion in the students. They were hesitant to express their ideas and often seemed to be going through the motions. I tried to encourage them to be more venturesome with tactics I had used successfully in the past but nothing worked.One day I asked them what was or, perhaps better, was not going on. Why were they so cautions and where was their enthnsiasm for learning They seemed relieved to talk about it and their response surprised me. Since pre-kindergarten, they explained, they had been programmed to perform well so they could get to the next level. They had been taught the downside of risk and encouraged to play it safe. What mattered most was getting into a good elementary school, middle school and high school so that they would finally be admitted to a top college. Having succeeded beyond their parents’ wildest expectations, they did not know why they were in college and had no idea what to do after graduation.In today’s market-driven economy we constantly hear that choice is the highest good and that competition fuels innovation. But this is not always true. Choice provokes anxiety and competition can quell (压倒) the imagination and discourage the spirit of experimentation that is necessary for creativity. In a world obsessed with ratings, well-meaning parents all too often train their children to jump through the hoops they think will lead to success.This was a bad bet--the course many young people were forced to take has not paid off. The lucrative jobs they expected as a reward for years of hard work have vanished and show little sign of returning in the near future. The difficult truth is that their education has not prepared them for the world they face.Though many young people have become disillusioned with Wall Street and all it represents and would like to pursue alternative careers, they have neither the educational nor financial resources to do so. The situation is critical--colleges and universities must be reformed in ways that allow students to develop the knowledge and skills they need for creative and productive lives. And parents must give their children the freedom to explore possibilities they never could have imagined. In order to become innovative, one must（）
Can Tony Blair Save the World of BooksAt the beginning of A Journey, Tony Blair boasts that he has "the soul of a rebel". Last week, he made good on that boast by conducting a gravity-defying act of literary presumption--pubhshing a hardback of some 720 pages, priced at ~25, tricked out with index, acknowledgments and 32 pages of photographic plates.According to Cathy Rentzenbrink, manager of the Richmond Waterstone’s: "These sales are brilliant and really exciting. You don’t often have customers almost breaking down the door to buy a book, but Blair is totally outselling Mandelson. I’ve not seen anything this big since Harry Potter or Dan Brown. This looks like the Christmas book of the year." She adds: "It’s very rare for a hardback to outsell a future paperback, but this might be one of those exceptions." Rentzenbrink says she does not know its Amazon discount, or if there’s a significant ebook and audiobook sale. What matters is that a fat hardback with a big print run is actually selling.Go into any bookshop today and you will find the unmistakable evidence of a business in the midst of a collective nervous breakdown: hardbacks discounted at 50%; heaped tables of "3 for 2"; and other hints of the death of print: andiobooks and advertisements for the Sony Reader, or the Elonex touch screen, or the Cybook Opus. This year, there are more than 20 competing e-readers.Across the Atlantic, Blair’s chunky memoir (回忆录) will seem even more antique. The American reading public is adopting the ebook with the enthusiasm of a great cousumer society. Wherever you go in the US, the electronic print of the hand-held screen glows like fairytale magic. Ebook sales are soaring, accompanied by terrible predictions about the future of publishing. The picture is all the more disturbing because it’s so hard to interpret, with competing diagnoses. Are we in intensive care or the morgue (太平间)Since 2000, the Anglo-American book business has been rocked by great disturbance. Google has digitised some 10 million titles. Barnes and Noble is for sale. Borders, bankrupt in the UK, clings on in the US. Here, Waterstone’s parent company, HMV, wants to sell. Amazon’s market share continues to soar. Asda, Tesco and the supermarket chains are said to be draining the life out of independent bookselling. In the US, it’s claimed that ebooks are now outselling many hardbacks. By the end of this year, 10.3 million Americans are expected to own e-readers, buying an estimated 100m ebooks.In the UK, electronic publishing lags behind the US, but many of the brightest publishing brains, notably Enhanced Editions, are looking hard at the potential of the book as application. Only a few people would dispute that it’s a matter of time before the ebook joins the iPod and the mobile phone as a vital component of the way we live. Ebooks, indeed, are already integral to the iPad and last week Amazon launched a sales campaign for its latest Kindle. Deplore this if you must, but be prepared: even the Oxford English Dictionary is now conceding that its third edition, 21 years in the making, will be published not on paper but online.The ￡25 hardback of Blair’s A Journey will certainly become a traditional bestseller. But many nervous industry observers are watching to see how many ebooks it sells. Within the book trade itself, all the main players (agents, editors, booksellers) have converted to e-reading, and now some authors are exploring the potential of the new technology. Stephen Fry is said to be developing a revolutionary application for his forthcoming autobiography. Yet many traditional publishers privately say that printed books will continue to be manufactured, bought and cherished.The buzz surrounding last week’s Kindle launch raises the possibility that the book is about to become swallowed up by an "iPod moment" for literature, similar to the transformation wrought on the music industry by downloading. Who knows Here’s where gazing into the crystal ball for the biggest IT revolution in 500 years gets really difficult.Tim Waterstone, who has had an unusual sense of what the British book buyer wants, remains sceptical. He concedes that the reference book market (dictionaries, encyclopedias) is "certain to go online". But what about fiction Biography Poetry Children’s books "Personally," he says, "I don’t think so."Like many great booksellers, Waterstone is a cultural conservative. As he talks, he spots a paperback classic on his 17:year-old daughter’s bookshelves, and launches into the old defence of ink and paper. "That’s incredible value," says Waterstone. "She’s a child of the digital age and she’s still buying books." So what’s the future A long pause. "The only honest thing to say is: I really don’t know."Another innovator, the writer Will Serf--whose Walking to Hollywood, an introduction for the movie business, has just been published--is in no doubt. "I’ve unknowingly acquired a Kindle," says Serf, "and I find that everything I read on it, especially Stieg Larsson, becomes nonsense. I’m inclined to blame the technology. With no physical similarity I think the text loses its .weight." Serf confesses to being unsure how much of his own backlist is available in ebook form.Sells response to the e-reader is echoed on the shop floor of Waterstone’s. Next to a discreet sign advertising "reading accessories" I found Elizabeth Squires, a mother of two, hesitated to buy Blair. This would be a departure for her because she buys "20 or 30 new books a year, all paperback, all fiction". Half of these she gets from Amazon. Audiobooks "Strictly for the kids." An ebook "No. Why should I I haven’t got anything to read it on." Is she tempted "I’ve been thinking about buying the Kindle, but it would never replace my book collection. Book lovers will always love books. There’s something irreplaceabie about a book. It gives you a physical, even an aesthetic, experience. For me, it’s an emotional thing. My books are my friends. There’s something about having a book in bed, about holding it, even smelling it, that I could never get from an e-reader. Isn’t the first thing you do when you move house, to rearrange your books"Elsewhere, the rearrangement of the book trade continues quickly. Last week’s New York Times Book Review contained no fewer than three separate items about the death of print. But paradoxically, the age of digitisation is both a golden age of ink and a boom time for narrative, in many media, on countless "platforms", from blogs, audiobooks to television soaps and Facebook.Bookshops are changing. The worst are becoming novelty item and greetings card booth, but the good ones are selling more books than ever, and the publishers, cursing the climate and moaning as usual about the state of the harvest, show few signs of cutting back on their output. Blair’s success suggests that the book-buying public may talk digital but actually buy printed books. How does Tim Waterstone think about the future of paper book（）
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