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A scorching sun, an endless sea of sand and a waterless, forbiddingly lonely land—that is the image most people have of deserts. But how true is this picture Deserts are dry lands where rainfall is low. This is not to say rain never falls in deserts: it may fall once or twice a year in a fierce torrent that fades almost as soon as it has begun, or which evaporates in the hot air long before it has got anywhere near the earth. It may fall in a sudden sweeping flood that carries everything in its path. Rains may only come once in five or six years or not fall for a decade or more. The Mojave desert in the United States remained dry for twenty-five years. Without water no living thing can survive, and one feature of the true desert land-scape is the absence of vegetation. With little rain and hardly any vegetation the land suffers under the sun. There are virtually no clouds or trees to protect the earth’s surface and it can be burning hot. Under the sun, soils break up and crack. Wind and torrential rain sweep away and erode the surface further. Eight million square kilometers of the world’s land surface is desert. Throughout history deserts have been expanding and retreating again. Cave paintings show that parts of the Sahara Desert were green and fertile about 10,000 years ago, and even animals like elephants and giraffes roamed the land. Fossil and dunes found in fertile and damp parts of the world show that these areas were once deserts. But now the creation of new desert areas is happening on a colossal scale. Twenty million square kilometers, an area twice the size of Canada, is at a high to very high risk of becoming desert. With a further 1.25 million square kilometers under moderate risk, an area covering 30% of the earth’s land surface is desert, becoming desert, or in danger of becoming desert. The rate of growth of deserts is alarming. The world’s dry lands which are under threat include some of the most important stock-rearing and wheat-growing areas and are the homes of 600～700 million people. These regions are becoming deserts at the rate of more than 58,000 square kilometers a year or 44 hectares a minute. In North Africa at least 100,000 hectares of cropland are lost each year. At this rate there is a high risk that we will be confined to living on only 50% of this planet’s land surface within one more century unless we are able to do something about it. What does the passage tell us about rainfall in the desert
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When catastrophic floods hit Bangladesh, TNT’s emergency-response team was ready. The logistics giant, with headquarters in Amsterdam, has 50 people on standby to intervene anywhere in the world at 48 hours’ notice. This is part of a five-year-old partnership with the World Food Program (WFP), the UN’s agency that fights hunger. The team has attended to some two dozen emergencies, including the Asian tsunami in 2004. "We’re just faster," says Ludo Oelrich, the director of TNT’s "Moving the World" program. Emergency help is not TNT’s only offering. Volunteers do stints around the world on secondment to WFP and staff are encouraged to raise money for the program (they generated euro2.5m last year). There is knowledge transfer, too: TNT recently improved the school-food supply chain in Liberia, increasing WFP’s efficiency by 15-20%, and plans to do the same in Congo. Why does TNT do these things "People feel this is a company that does more than take care of the bottom line," says Mr. Oelrich. "It’s providing a soul to TNT." In a 2006 staff survey, 68% said the pro-bono activities made them prouder to work at the company. It also helps with recruitment: three out of four graduates who apply for jobs mention the WFP connection. Last year the company came top in the Dow Jones Sustainability Index. TNT’s experience illustrates several trends in corporate philanthropy. First, collaboration is in, especially with NGOs. Companies try to pick partners with some relevance to their business. For TNT, the food program is a good fit because hunger is in part a logistical problem. Standard Chartered, a bank, is working with the Bangladesh Rural Advancement Committee on microfinance and with other NGOs on a campaign to help 10m blind people. Coca-Cola has identified water conservation as critical to its future as the world’s largest drinks company. Last June it announced an ambitious collaboration with WWF, a global environmental organization, to conserve seven major freshwater fiver basins. It is also working with Greenpeace to eliminate carbon emissions from coolers and vending machines. The co-operation is strictly non-financial, but marks a change in outlook. "Ten years ago you couldn’t get Coca-Cola and Greenpeace in the same room," says Neville Isdell, its CEO. Second, what used to be local community work is increasingly becoming global community work. In the mid-1990s nearly all IBM’s philanthropic spending was in America; now 60% is outside. Part of this involves a corporate version of the peace corps: young staff get one-month assignments in the developing world to work on worthy projects. The idea is not only to make a difference on the ground, but also to develop managers who understand how the wider world works. Third, once a formal program is in place, it becomes hard to stop. Indeed, it tends to grow, not least because employees are keen. In 1996 KPMG allowed its staff in Britain to spend two hours a month of their paid-for time on work for the community. Crucially for an accountancy firm, the work was given a time code. After a while it came to be seen as a business benefit. The program has expanded to half a day a month and now adds up to 40,000 donated hours a year. And increasingly it is not only inputs that are being measured but outputs as well. Salesforce.com, a software firm, tries to measure the impact of its volunteer programs, which involved 85% of its employees last year. All this has meant that straightforward cash donations have become less important. At IBM, in 1993 cash accounted for as much as 95% of total philanthropic giving; now it makes up only about 35%. But cash still matters. When Hank Paulson, now America’s treasury secretary, was boss of Goldman Sachs, he was persuaded to raise the amount that the firm chipped in to boost employees’ charitable donations. Now it is starting a philanthropy fund aiming for $1 billion to which the partners will be encouraged to contribute a share of their pay. No doubt that is good for the bank’s soul. Which of the following is NOT an NGO
已知f(x)=loga(x+1)，点P是函数y=f(x)图象上任意一点，点P关于原点的对称点Q的轨迹是函数y=g(x)的图象． (1)当0＜a＜1时，解不等式：2f(x)+g(x)≥0； (2)当a＞1，x∈[0，1]时，总有f(x)+g(x)≥m恒成立，求m的范围.
Beginning in October, more than 13,000 McDonald’s restaurants in America will use a new kind of cooking oil. McDonald’s aims to make its French fries and other fried foods healthier.The change will not affect the taste or the number of calories in the food. But by changing the cooking oil, McDonald’s says, it hopes to cut by nearly half the amount of trans-fatty acids(转换脂肪酸) in French fries and reduce the amount of saturated fats(饱和脂肪) by 16 percent. Scientists believe that trans-fatty acids and saturated fats raise cholesterol(胆固醇) levels and increase the risk of heart disease.McDonald’s new step is important because McDonald’s is an industry leader and other fast-food chains and food processors may follow the lead.For McDonald’s, the action comes at a time when Americans are becoming more and more concerned about; obesity(肥胖) is an increasing pressure on food companies to offer healthy food to consumers.After three years of study, McDonald’s officials say they are switching oil that is lower in saturated fats and trans-fatty acids. McDonald’s says the change will not cause higher coats for consumers.Though there is some change, scientists say that the amount of trans-fat in foods at McDonald’s and at other fast-food companies is still important. More than 13,000 McDonald’s restaurants in America will use a new kind of cooking oil to（）
Man: That’s the most boring seminar I’ve been to in a long time. Woman: Well, it wasn’t the regular speaker. She got sick at the last minute. Man: I’m surprised they didn’t have a better substitute. Question: What does the man mean
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