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A warm drink of milkbefore bed has long been the best choice for those wanting a good night'ssleep. But now a study has found it really does help people nod off—if it ismilked from a cow at night.

  Researchers have discovered that“night milk” contains more melatonin(褪黑激素), which has been proven tohelp people feel sleepy and reduce anxiety.

  The study, by researchersfrom Seoul, South Korea, involved mice being fed with dried milk powder madefrom cows milked both during the day and at night.

  Those given night milk, whichcontained 10 times the amount of melatonin, were less active and less anxiousthan those fed with the milk collected during daytime, according to the studypublished in The Journal of MedicinalFood.

   Night milk quickened the startof sleep and caused the mice to sleep longer.

   While the effect of cowsmilk harvested at different time has not been tested on humans up to now,taking melatonin drugs has been suggested to those who are struggling to fallasleep at night.

   Previous studies have alsoindicated that milk can be excellent for helping sleep because of the calciumcontent, which helps people to relax.

  Milk is also sugar-free andadditive-free with nutritionists recommending skimmed milk as the best choicebefore bed as it is the least fattening. The more fat you take in beforebedtime, the greater burden you will put on your body at night.

    The Rugby (英式橄榄球) World Cup is currently being held in New Zealand. The tournament, due to finish on October 23, is living up to the famous English saying, “Rugby is a thug's (暴徒) game played gentlemen. ”

    The games are physically aggressive; the tackles (冲撞) on the pitch are brutal; but the end of each match is a civilized affair. Players shake hands and applaud each other. Of course, the other side to this saying is: "Football is a gentleman's game played by thugs. " Indeed, unlike soccer players, rugby players don't often question the referee's (裁判员) decisions or pretend to be injured when they are not.

    “Football could learn a lot from rugby," said Brian Moore, a former England rugby player "The wonderful spirit of rugby is: there is a gentlemanly code to it. You play hard on the pitch, but you always respect your opponent..

    Rugby is mainly played in Europe. Australia, New Zealand and parts of Africa. "It is more enjoyable to play than soccer because you are always involved in the game," said Peter, a Welsh rugby coach. "Rugby is also a far superior test of strength, stamina (耐力) and determination. "

    Most professional rugby players are large, strong and weigh over 90 kilograms. People who play the sport need to be tough and be prepared to get hurt. Black eyes, broken bones, lost teeth and being knocked unconscious—all these are common injuries. Former British Prime Minister Gordon Brown is blind in one eye thanks to a rugby accident at school.

    In England, children begin playing the game at school at the age of 8. When they enter high school, many begin to play full contact rugby. Children are taught to play for around one hour a week during their PE lessons. Most schools have a rugby team. Children who play for the school team are usually the sportiest kids, and are seen as brave and athletic.

    In the world today, all of the people need recreation(消遣). We cannot work all the time if we are going to keep healthy and enjoy life.

    Everyone has his own way of relaxing. Perhaps the most popular form is to take part in sports. There are team sports, such as basketball and football. There are also individual(个人的) sports, such as swimming and running. Skating and mountain climbing are the most popular recreation for people who like to be outdoor. Not everyone who enjoys sports likes to take part in them. Many people like watching them on TV or listening to them on the radio. So many people like some forms of recreation, such as watching TV, singing and dancing. It doesn't matter whether we like indoor recreation or take part in outdoor sports. It is important for everyone to relax from time to time and enjoy some forms of recreation.

    Although his 1-year-old smart-phone still works perfectly, Li Jijia already feels the need to replace it.

    “There are many better ones available now. It's time to upgrade(更新）my phone.”

    Li's impatience is shared by many. Shortly after the season when new products are released（发布，发售）, many consumers feel the urge to upgrade their electronic equipment, even though the ones they have still work just fine.

    As consumers' minds are occupied by Apple's newly released products and debate whether the Google tablet is better than the new Amazon Kindle, it might be time to take a step back and ask: “Do we really need the latest upgrades?”

    According to Donald Norman, an American author, “planned obsolescence (淘汰）” is the trick behind the upgrading culture of today's consumer electronics industry.

    Electronics producers strategically release new upgrades periodically, both for hardware and software, so that customers on every level feel the need to buy the newest version.

“This is an old-time trick—they're not inventing anything new,” Norman said. “This is a wasteful system through which companies--many of them producing personal electronics-- release poor-quality products simply because they know that, in six months or a year, they'll put out a new one.”

    But the new psychology of consumers is part of this system, as Norman admitted, “We now want something new, something pretty, the next shiny thing.” In its most recent year, Apple's profit margin(利润) was more than 21 percent. At Hewlett-Packard, the world's biggest PC maker, it was only 7 percent.

    Apple's annual upgrades of its products create sales of millions of units as owners of one year's MacBook or iPhone line up to buy the newest version, even when the changes are slight.

    As to Li Jijia, the need for upgrading his smart-phone comes mainly from friends and classmates. When they are switching to the latest equipment, he worries about feeling left out.

    “Some games require better hardware to run,” said Li. “If you don't join in, you lose part of the connection to your friends.”

    Last year marked the 100th anniversary of the end of World War I. There were events around the world in memory of those who died in the conflict. We have picked out three of them inEuropean countries. Let's take a look.

    Belgium

    In a park, the famous Belgian artist Koen Vanmechelen had an exhibition called Coming World, Remember Me. The work consisted of 600,000 individual(个别的) clay sculptures, one for each person killed during the World War. In the center of the exhibition was a big egg made of clay, symbolizing a new world.

    UK

    In a small town called Aldridge, almost 100 houses in one street were covered with 24,000 poppies and statues of soldiers. They stood for the men from the area who had been' killed in the war. The flowers were chosen because of a poem written by the Canadian doctor John McCrea in 1915. They made people think of fields of blood.

    France

    The British artist Guy Denning arrived in La Feuille, a small town in the northwest of France, to stick life-size drawings of soldiers who never came back home. Armed with glue and a brush, Denning stuck his drawings carefully on walls. Before long 112 men, mainly young adults, were brought back to mind, if not to life.

Crocodiles today look very similar to ones from 200 million years ago. There are also very few species alive today—just 25. Other animals such as lizards (蜥蜴) and birds have achieved a diversity of many thousands of species in the same amount of time or less.

Prehistory also saw types of crocodile we don't see today, including giants as big as dinosaurs, plant-eaters, fast runners and snake-like forms that lived in the sea. The rate of their evolution is generally slow, but occasionally they evolve more quickly because the environment has changed. In particular, their evolution speeds up when the climate is warmer, and their body size increases.

The body size of crocodiles is important because it interacts with how fast animals grow, how much food they need, how big their populations are and how likely they are to become extinct. The limited diversity of crocodiles and their apparent lack of evolution is a result of a slow evolutionary rate. It seems the crocodiles arrived at a body plan that was very efficient and perfect enough that they didn't need to change it in order to survive. This perfection could be one explanation why crocodiles survived Cretaceous period (白垩纪), in which the dinosaurs died out.

Crocodiles generally develop better in warm conditions because they cannot control their body temperature and require warmth from the environment. The climate during the age of dinosaurs was warmer than it is today, and that may explain why there were many more varieties of crocodiles than we see now. Being able to draw energy from the sun means they do not need to eat as much as a warm-blooded animal like a bird or a mammal (哺乳动物).