A warm drink of milk before bed has long been the best choice for those wanting a good night's sleep. But now a study has found it really does help people nod off—if it is milked from a cow at night.

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

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

       Those givennight milk, which contained 10 times the amount of melatonin, were less active and less anxious than those fed with the milk collected during daytime, according to the study published in The Journal of Medicinal Food.

       Night milk quickened the start of sleep and caused the mice to sleep longer.

       While the effect of cows milk 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 fall asleep at night.

Previous studies have also indicated that milk can be excellent for helping sleep because of the calcium content, which helps people to relax.

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

    Over the last week, a "poisonous kale（甘蓝菜）" theory has been going widespread after an article warned that the vegetable was associated with a variety of medical conditions. It's time to separate fear from fact on the health benefits of kale.

    As a member of the cabbage family, kale is low in calories and rich in nutrients and minerals, especially vitamin A,C and K. Consumed for thousands of years, it's been a health plus for millions of eaters throughout the world.

    However, numerous web articles have reported on some evidence offered by a medicine researcher. The researcher found that thallium（铊）was detected in a few people who were heavy consumers of kale. Thallium is a heavy metal often found in trace amounts（微量）in soil and minerals. His conclusion was that these medical conditions were connected to the impact that trace amounts of thallium detected in some kale samples had on the body.

    I don't think the conclusion is based on a strict scientific basis. It's essential to point out that the original report was in a web magazine, not a scientific journal which is subject to peer review by other scientists. A scientific review includes a careful evaluation of how the findings and conclusions were made. Certain factors are critical before an evidence-based conclusion can be made, such as: how many people were in a study; how well controlled were other factors; how much kale was consumed and for how long; how much thallium was in the kale.

    It is a fact that kale and other vegetables can absorb thallium from the soil. But the ability for a plant to absorb traces of a chemical does not automatically make it harmful to your health. And even finding measurable amounts of thallium in someone's body doesn't imply that the thallium is causing an ill health effect, according to the CDC.

    But we can still learn a lesson from this. Plants grow in soil. Growers must continue to be careful in monitoring the quality of their soil. And what about consumers? Eat your kale—and include lots of other colorful fruits and vegetables. As with all things in nature, variety is key for good health.

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    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.

    Two of the saddest words in the English language are "if only". I live my life with the goal of never having to say those words, because they convey regret, lost opportunities, mistakes, and disappointment.

    My father is famous in our family for saying "Take the extra minute to do it right." I always try to live by the "extra minute" rule. When my children were young and likely to cause accidents, I always thought about what I could do to avoid an "if only" moment, whether it was something minor like moving a cup full of hot coffee away from the edge of a counter, or something that required a little more work such as taping padding (衬垫) onto the sharp corners of a glass coffee table.

    I don't only avoid those "if only" moments when it comes to safety. It's equally important to avoid "if only" in our personal relationships. We all know people who lost a loved one and regretted that they had foregone an opportunity to say "I love you" or "I forgive you." When my father announced he was going to the eye doctor across from my office on Good Friday, I told him that it was a holiday for my company and I wouldn't be here. But then I thought about the fact that he was 84 years old and I realized that I shouldn't give up an opportunity to see him. I called him and told him I had decided to go to work on my day off after all.

    I know there will still be occasions when I have to say "if only" about something, but my life is definitely better because of my policy of doing everything possible to avoid that eventuality. And even though it takes an extra minute to do something right, or it occasionally takes an hour or two in my busy schedule to make a personal connection, I know that I'm doing the right thing. I'm buying myself peace of mind and that's the best kind of insurance for my emotional well-being.

    It seems as if Christmas and their birthday aren't enough. Kids have another day which revolves (围绕) around them. There are a lot of funny activities in Shanghai especially for families as Children's Day falls on 1^st June.

    ①Indoor activities at Big E

    Big E is a great place for kids. All kinds of ball games can be found here. This Sunday, there are some other interesting activities: free movies and a magic show with three sessions (场) between 9 a. m. and 6 p. m.

    ②The Wizard of Oz at Kerry Hotel

    If eating and relaxing is what your family are interested in, Kerry Hotel should be your favourite place. The COOK and The MEAT both offer excellent brunch (早午餐) every weekend. Besides, The BREW will organize The Wizard of Oz for children in a repeat of its special Easter performance.

    ③Brunch at City Bistro

    If you're looking for a restaurant with a more relaxing atmosphere and lower price than either The COOK or The MEAT, then go to City Bistro. A special discount on its brunch this Sunday has never happened before. While parents are enjoying the food, their children can play in the kids' corner and let parents catch their breath.

    ④Children's exhibition at Gallery G1

    If going out for brunch is too regular, families can try something a little more cultural at Gallery G1. There is an exhibition of children's artwork named My Sky, which will be displayed this weekend. There are also a number of artistic (艺术的) activities for kids to try.

    ⑤Get creative at Petit Chameleon

    Petit Chameleon at the Daycare centre is organizing a new activity named Art from the Start to show kids' creative ability. The event is about ancient Greece. On Sunday, you will see kids make their own armors (盔甲).

    Being able to take advantage of truly unlimited data is a smartphone user's dream, but everyone I've talked to about 5G is more excited about the usage unlocked by next - generation wireless devices. From smart home security to self - driving cars, all the Internet - connected equipment in your life will be able to talk to each other at lightning - fast speed with reduced delay.

    "5 G is one of those forerunners, along with artificial intelligence, of this coming data age," said Steve Koenig, senior director of market research for the Consumer Technology Association. "Self - driving vehicles are emblematic in this data age - they show application of data completely. With one single task, driving, you have large amounts of data coming from the vehicle itself, and a variety of sensors (传感器)are collecting a lot of information to model its environment as it moves. It's pulling in data from other vehicles about conditions down the road. There's lots of data behind that task, which is why we need the speed and lower latency ((延迟).

    AR glasses and virtual (虚拟的)reality headphones haven't yet been inside the mainstream, but tech companies are joyfully saying that such equipment will eventually replace our smartphones. With 5G, that could actually happen. This is notable because companies such as Apple are reportedly developing AR glasses to improve - or even replace - smartphones.

    Ericsson showed at February's Mobile World Congress in 2019 how smart glasses could become faster and lighter with a 5G connection, because instead of being weighed down with components, the glasses could rely on outside equipment for processing power.

    But don't get too excited. There's still a lot of work to be done in the meantime, including some necessary testing to make sure the radio plays nicely with basic systems and service construction so that 5G isn^'t concentrated only in big cities.