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Why does cream go bad faster than butter? Some researchers think they have the answer, and it comes down to the structure of the food, not its chemical composition—a finding that could help rid some processed foods of chemical preservatives.Cream and butter contain pretty much the same substances, so why cream should sour much faster has been a mystery. Both are emulsions—tiny globules (小球体)of one liquid evenly distributed throughout another. The difference lies in what’s in the globules and what’s in the surrounding liquid, says Brocklehurst, who led the investigation.In cream, fatty globules drift about in a sea of water. In butter, globules of a watery solution are locked away in a sea of fat. The bacteria which make the food go bad prefer to live in the watery regions of the mixture. “This means that in cream, the bacteria are free to grow throughout the mixture.” He says.When the situation is reversed, the bacteria are locked away in compartments buried deep in the sea of fat. Trapped in this way, individual colonies cannot spread and rapidly run out of nutrients. They also slowly poison themselves with their waste products. “In butter, you get a self-limiting system which stops the hotelier growing.” Says Brocklehurst.The researchers are already working with food companies keen to see if their products can be made resistant to bacterial attack through alterations to the food’s structure. Brocklehurst believes it will be possible to make the emulsions used in salad cream, for instance, more like that in butter. The key will be to do this while keeping the salad cream liquid and not turning it into a solid lump.1.The significance of Brocklehurst’s research is that(  ).2.According to the researchers, cream sours faster than butter because bacteria  (  ).  3.According to Brocklehurst, we can keep cream fresh by (  ).  4.The word ‘‘colonies’’ refers to  (  ).  5.Commercial application of the research finding will be possible if salad cream can be made resistant to bacterial attack(  ).

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Global warming is causing more than 300,000 deaths and about $125 billion in economic losses each year, according to a report by the Global Humanitarian Forum, an organization led by Kofi Annan, the former United Nations secretary general.The reports, to be released Friday, analyzed data and existing studies of health, disaster, population and economic trends. It found that human-influenced climate change was raising the global death rates from illnesses including malnutrition and heat-related health problems.But even before its release, the report drew criticism from some experts on climate and risk, who questioned its methods and conclusions.Along with the deaths, the report said that the lives of 325 million people, primarily in poor countries are being seriously affected by climate change. It projected that the number would double by 2030.Roger Pielke Jr., a political scientist at the University of Colorado, Boulder, who studies disaster trends, said the Forum’s report was “a methodological embarrassment” because there was no way to distinguish deaths or economic losses related to human-driven global warming amid the much larger losses resulting from the growth in populations and economic development in vulnerable regions. Dr. Pielke said the climate change is an important problem requiring our utmost attention.” But the report, he said, “will harm he cause for action on both climate change and disasters because it is so deeply flawed.”However, Soren Andreasen, a social scientist at Dalberg Global Development Partners who supervised the writing of the report, defended it, saying that it was clear that the numbers were rough estimates. He said the report was aimed at world leaders, who will meet in Copenhagen in December to negotiate a new international climate treaty.In a press release describing the report, Mr. Annan stressed the need for the negotiations to focus on increasing the flow of money from rich to poor regions to help reduce their vulnerability to climate hazards while still curbing the emissions of the heat-trapping gases. More than 90% of the human and economic losses from climate change are occurring in poor countries, according to the report.1.What is the finding of the Global Humanitarian Forum?2.What do we learn about the Forum’s report from the passage?3.What does Dr. Pielke say about the Forum’s report?4.What is Soren Adreasen’ s view of the report?5.What does Kofi Annan say should be the focus of the Copenhagen conference?

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A recurring criticism of the UK’s university sector is its perceived weakness in translating new knowledge into new products and services.Recently, the UK National Stem Cell Network warned the UK could lose its place among the world leaders in stern cell research unless adequate funding and legislation could be assured. We should take this concern seriously as universities are keys in the national innovation system.However, we do have to challenge the unthinking complaint that the sector does not do enough in taking ideas to market. The most recent comparative data on the performance of universities and research institutions in Australia, Canada, USA and UK shows that, from a relatively weak starting position, the UK now leads on many indicators of commercialization activity.When viewed at the national level, the policy interventions of the past decade have helped transform the performance of UK universities. Evidence suggests the UK’s position is much stronger than in the recent past and is still showing improvement. But national date, asks the very large variation in the performance of individual universities. The evidence shows that a large number of universities have fallen off the back of the pack, a few perform strongly and the rest chase the leaders.This type of uneven distribution is not peculiar to the UK and mirrored across other economic. In the UK, research is concentrate; less than 25% of universities receive 75% of the research funding. These same universities are also the institutions producing the greatest share of PhD graduates, science citations, patents and license income. The effect of policies generating long-term resource concentration have also created a distinctive set of universities which are research-led and commercially active. It seems clear that the concentration of research and commercialization work creates differences between universities.The core objective for universities which are research-led must be to maximize the impact of their research efforts. These universities should be generating the widest range of social economic and environmental benefits. In return for the scale of investment they should share their expertise in order to build greater confidence in the sector.Part of the economic recovery of the UK will be driven by the next generation of research commercialization spilling out of our universities. There are three dozen universities in the UK which are actively engaged in advanced research training and commercialization work.If there was a greater coordination of technology transfer offices within regions and a simultaneous investment in the scale and functions of our graduate schools, universities could, and should, play a key role in positioning the UK for the next growth cycle.1.What does the author think of UK universities in terms of commercialization?2.What does the author say about the national data on UK universities’ performance in commercialization?3.We can infer from Paragraph 5 that “policy interventions” refers to (  ).4.What does the author suggest research-led universities do?5.How can the university sector play a key role in the UK’s economic growth?

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What’s the one word of advice a well-meaning professional would give to a recent college graduate? China? India! Brazil? How about trade?When the Commerce Department reported last week that the trade deficit in June approached $50 billion, it set off a new round of economic doom saying. Imports, which soared to $200.3 billion in the month, are subtracted in the calculation of gross domestic product. The larger the trade deficit, the smaller the GDP. Should such imbalances continue, pessimists say, they could contribute to slower growth.But there’s another way of looking at the trade data. Over the past two years, the figures on imports and exports seem not to signal a double-dip recession—a renewed decline in the broad level of economic activity in the United States—but an economic expansion.The rising volume of trade—more goods and services shuttling in and out of the United States—is good news for many sectors. Companies engaged in shipping, trucking, rail freight, delivery, and logistics have all been reporting better than expected results. The rising numbers signify growing vitality in foreign markets—when we import more stuff, it puts more cash in the hands of people around the world, and U.S. exports are rising because more foreigners have the ability to buy the things we produce and market. The rising tide of trade is also good news for people who work in trade sensitive businesses, especially those that produce commodities for which global demand sets the price—agricultural goods, mining, metals, oil.And while exports always seem to lag, U.S. companies are becoming more involved in the global economy with each passing month. General Motors sells as many cars in China as in America each month. While that may not do much for imports, it does help GM’s balance sheet and hence makes the Jobs of U.S.-based executives more stable.One great challenge for the U.S. economy is slack domestic consumer demand. Americans are paying down debt, saving more, and spending more carefully. That’s to be expected, given what we’ve been through. But there’s a bigger challenge. Can U.S.-based businesses, large and small, figure out how to get a piece of growing global demand? Unless you want to pick up and move to India or Brazil, or China, the best way to do that is through trade. It may seem obvious, but it’s no longer enough simply to do business with our friends and neighbors here at home.Companies and individuals who don’t have a strategy to export more, or to get more involved in foreign markers, or to play a role in global trade, are shutting themselves out of the lion’s share of economic opportunity in our world.1.How do pessimists interpret the U.S. trade deficit in June?2.What does the author say about the trade data of the past two years?3.Who particularly benefit from the rising volume of trade?4.What is one of the challenges facing the American economy?5.What is the author’s advice to U.S. companies and individuals?

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