Most drinks stating that they are fruit flavored contain no fruit at all, while most of the rest contain only a small quantity of fruit, according to a study carried by the British Food Commission.

    "Shoppers need to check the labels before buying drinks, though sometimes the actual content can be nonexistent," said Food Commission spokesperson Ian Tokelove. "Food production is highly competitive. {#blank#}1{#/blank#} It will increase profits, and consumers won't always realize they are being tricked."

    Flavorings are focused on the flavors of natural food products such as fruits, meats and vegetables, or creating flavor for food products that do not have the desired flavors. Researchers analyzed the contents of 28 strawberryflavored products sold in stores.{#blank#}2{#/blank#} Of the 11 products that did contain strawberries, five of them contained less than one percent real fruit. In addition, each juice box contained nearly eight teaspoons of sugar.

    {#blank#}3{#/blank#} Let's take jam as an example. Some strawberryflavored jam was labeled as containing no artificial color1 s, flavors, or sweeteners, but it contained ly no strawberries at all.

    {#blank#}4{#/blank#} Consumers have the rights to know clearly about what they have bought. Under current UK law, food packages do not have to distinguish between natural and artificial flavoring. "Describing a product as strawberry flavor and covering the surface of the packet with pictures of strawberries is misleading.{#blank#}5{#/blank#} Unfortunately, it is also legal and widespread," Tokelove said. "It's time to take measures to protect the consumers' rights."

A. They found that about 60 percent of them didn't contain any fruit at all.

B. Even products advertised as more natural often contained no fruit.

C. The products which contain real fruit are popular with people.

D. Actually the product contains just a tiny percentage of strawberry or even no fruit at all.

E. It is important and necessary to demand a small amount of flavoring in the products.

F. If companies can cut their costs by using flavoring, they are likely to do so.

G. The Food Commission suggested all flavors used in a product should be listed on the packaging.

    In recent years, remote-sensing technologies have become ordinary in archaeological fieldwork（实地考察）. Such tools for excavation produce rapid results and cause no damage to archaeological sites. They are highly accurate and usually cost effective. Here are three of the modern archaeologist's most trusted remote-sensing tools.

    As the simplest of the remote-sensing techniques that archaeologists use, aerial（空中的）photography allows experts to see aspects of a site that may be invisible from the ground, such as the way in which something such as a town, garden, or building is arranged and traces of old walls and roads. The technique involves taking photographs with conventional cameras and filming from airplanes, helicopters, hot-air balloons, or other airborne vehicles.

    Geographic Information System (GIS) contains a large amount of field data archaeologists typically collect in and around excavation sites. While in the field, archaeologists use GIS on their computers to make and manage detailed site maps, and they can combine the results of remote-sensing tests with maps of the region created with the aid of Global Positioning System. Resulting maps sort the most archeologically promising areas and display these sites three-dimensionally.

    Ranging in size from small handled models that one places against the ground to larger ones that one across a site, Ground Penetrating Radar (GPR) devices use low-power radio waves to detect changes underground. Unlike traditional radar, which broadcasts into the air and uses a dish to focus the returned waves, GPR uses a small but sensitive receiver placed directly against the ground. Depending on their needs, archaeologists can adjust radio frequencies upward for shallow sites or downward for deeper areas, though GPR devices produce the greatest definition（清晰度）when reading depths of three feet or less.

    A large body of research has been developed in recent years to explain many aspects of willpower. Most of the researchers exploring self-control do so with an obvious goal in mind: How can willpower be strengthened? If willpower is truly a limited resource, as the research suggests, what can be done to make it stay strong?

    Avoiding temptation (诱惑) is an effective method for maintaining self-control, which is called the "out of sight, out of mind" principle. One recent study, for instance, found office workers less attracted to candy in the desk drawer than that on top of their desks, in plain sight.

    The research suggesting that we possess a limited reservoir of self-control raises a troubling question. When we face too many temptations, are we to fail? Not necessarily. Researchers don't believe that one's willpower is ever completely exhausted. Rather, people appear to hold some willpower in reserve, saved for future demands. The right motivation allows us to tap into those reserves, allowing us to carry on even when our self-control strength has been run down. High motivation might help overcome weakened willpower-at least to a point.

    Willpower may also be made less vulnerable (脆弱) to being exhausted in the first place. Researchers who study self-control often describe it as being like a muscle that gets tired with heavy use. But there is another aspect to the muscle comparison, they say. While muscles become exhausted by exercise in the short term, they are strengthened by regular exercise in the long term. Similarly, regular practices of self-control may improve willpower strength.

    The evidence from willpower-exhaustion studies also suggests that making a list of resolutions on New Year's Eve is the worst possible approach. Being exhausted in one area can reduce willpower in other areas, so it makes more sense to focus on a single goal at a time. In other words, don't try to quit smoking, adopt a healthy diet and start a new exercise plan at the same time. Taking goals one by one is a better approach. Once a good habit is in place, Baumeister says, you'll no longer need to draw on your willpower to maintain the behavior. Eventually healthy habits will become routine, and won't require making decisions at all.

    A team of international scientists is due to set off for the world's biggest iceberg in a mission aiming to answer fundamental questions about the impact of climate change in the polar regions. The scientists, led by the British Antarctic Survey (BAS), are trying to reach a newly revealed ecosystem that had been hidden for 120,000 years below the Larsen C ice shelf.

    Last year, part of the Larsen C ice shelf calved (崩解) away, forming a huge iceberg-A68—which is four times bigger than London, and revealing life beneath for the first time. Now scientists say it is a race against time to explore these new ecosystems before they are transformed to the light. Marine biologist Dr Katrin Linse from the BAS is leading the mission.

    "The calving of A68 provides us with a unique opportunity to study marine life as it responds to a huge environment change," she said. "It is important that we get there quickly before the undersea environment changes as sunlight enters the water."

    Professor David Vaughan, science director at the BAs, said, "We need to be bold (大胆的) on this one. Larsen C is a long way south and there's lots of sea ice in the area, but this is important science, so we will try our best to get the team where they need to be. He said climate change had already affected the sea around Antarctica and is warming some coastal waters. "Future warming may make some habitats warm. Where these habitats support unique species that are adapted to love the cold and not the warm, those species are going to either move or die."

    There is growing concern about the possible impact of climate change in the Antarctic. Earlier this month, a report revealed that melting ice sheets in Greenland and Antarctica are speeding up the already fast pace of the sea level rise. The research, published by the National Academies of Science, Engineering and Medicine, said, "At the current rate, the world's ocean will be, on average, at least 60cm higher by the end of the century." However, it found that the process is accelerating, and more than three quarters of the acceleration since 1993 is due to melting ice sheets in Greenland and Antarctica, the study shows.

    Breathing dirty air comes at a high price. Air pollution lowers the average life spans (寿命) by a year worldwide and in more polluted parts of Asia and Africa, dirty air shortens lives up to twice that much. Scientists shared their new findings in Environmental Science & Technology Letters. The study used data gathered in 2016 as part of a project known as the Global Burden of Disease and was the first major country-by-country look at the connection between the length of life and what's known as fine PM.

    Air pollution has been linked to many health problems. Most earlier studies had looked at how tiny air pollutants affected rates of illness or death. Joshua Apte is an environmental scientist at the University of Texas at Austin. By looking at life expectancy (预期寿命), his team had hoped to make the threat easier to understand. PM2.5 is what scientists call tiny particles (颗粒) of pollution in the air. Higher levels of PM2.5 can cause health problems and cut months, if not years, from the average length of life. This analysis shows how pollution affects life expectancy in different parts of the world.

    The World Health Organization (WHO) recommends limiting PM2.5 to 10 micrograms per cubic meter of air. Apte's group calculated how holding pollution to this low level would help people. In countries with very dirty air, meeting this standard would lengthen people's lives. However, in countries whose air already meets this standard, the study shows no gain in life expectancy. In other words, meeting the WHO standard won't reduce health costs resulting from dirty air because even below 10 micrograms per cubic meter, pollution still causes serious risks. Meanwhile, the scientists compared how other threats including smoking and cancer shorten the length of life across the globe.

A new study reveals that pigeons (鸽子) can tackle some problems just like artificial intelligence, enabling them to solve difficult tasks that might challenge humans. Previous research has theorized that pigeons employ a problem-solving strategy, involving a trial-and- error approach, which is similar to the approach used in AI models but differs from humans' reliance on selective attention and rule use. To examine it, Brandon Turner, a psychology professor at the Ohio State University, and his colleagues conducted the new study. 

In the study, the pigeons were presented with various visual images, including lines of different widths and angles, and different types of rings. The pigeons had to peck (啄) a button on the right or left to indicate the category to which the image belonged. If they got it correct, they received food; if they were wrong, they received nothing. Results showed that, through trial and error, the pigeons improved their accuracy in categorization tasks, increasing their correct choices from about 55% to 95%. 

Researchers believed pigeons used associative learning, which is linking two phenomena with each other. For example, it is easy to understand the link. between "water" and "wet". "Associative learning is frequently assumed to be far too primitive to. explain complex visual categorization like what we saw the pigeons do," Turner said. But that's exactly what the researchers found. 

The researchers' AI model tackled the same tasks using just the two simple mechanisms that pigeons were assumed to use: associative learning and error correction. And, like the pigeons, the AI model learned to make the right predictions to significantly increase the number of correct answers. For humans, the challenge when given tasks like those given to pigeons is that they would try to come up with rules that could make the task easier. But in this case, there were no rules, which upsets humans. 

What's interesting, though, is that pigeons use this method of learning that is very similar to AI designed by humans, Turner said. "We celebrate how smart we are that we designed artificial intelligence: at the same time, we regard pigeons as not clever animals," he said.