Honey from the African forest is not only a kind of natural sugar, it is also delicious. Most people, and many animals, like eating it. However, the only way for them to get that honey is to find a wild bees' nest and take the honey from it. Often, these nests are high up in trees, and it is difficult to find them. In parts of Africa, though, people and animals looking for honey have a strange and unexpected helper—a little bird called a honey guide.

    The honey guide does not actually like honey, but it does like the wax(蜂蜡) in the beehives(蜂房). The little bird cannot reach this wax, which is deep inside the bees' nest. So, when it finds a suitable nest, it looks for someone to help it. The honey guide gives a loud cry that attracts the attention of both passing animals and people. Once it has their attention, it flies through the forest, waiting from time to time for the curious animal or person as it leads them to the nest. When they finally arrive at the nest, the follower reaches in to get at the delicious honey as the bird patiently waits and watches. Some of the honey, and the wax, always falls to the ground, and this is when the honey guide takes its share.

    Scientists do not know why the honey guide likes eating the wax, but it is very determined in its efforts to get it. The birds seem to be able to smell wax from a long distance away. They will quickly arrive whenever a beekeeper is taking honey from his beehives, and will even enter churches when beeswax candles are being lit.

    Electronic sensors built into paper could be used in a range of ways from information storage to touch screens and more.

    Electronic sensors built into cartons（纸盒）may make it easier to tell when it's time to throw out rotten milk or orange juice. And that's just the start. At least that's the goal for researchers working on putting electronics into paper. They're trying to figure out how to combine the flexibility, low-cost and recyclability of paper with the information-carrying ability of electronics.

Daniel Torbjork, a physics graduate student in Finland, has been working on the problem. He's published a review of the field in the journal Advanced Materials.

    Much research has been focused in this area. While most electronic applications require patterned conducting structures, conductive paper could be used in applications such as energy storage devices, sensors, electric heaters and others, according to Torbjork.

     “You could even have some interactive functions in magazines,” Torbjork said, “You could put a simple game in a package. If you want a touch screen, press a button and then something happen. Sensors in paper could tell us when something has gone bad.”

    Additional applications, such as information storage and security paper, have been suggested for magnetic papers containing magnetite. In Massachusetts, researchers have figured out how to post a video of such a device put into a paper airplane.

    German researchers have also put electronic chips in paper bank notes to defend counter-feiters（造伪币者）. Paper is a good material but printing electronics also requires low-cost manufacturing. As many US and European paper makers lose market share to cheaper paper from China, these big paper companies are looking for added value products. That's where electronic paper devices could make a difference.

    “The major obstacles are paper's large surface roughness and chemical impurities.” Torbjork says. But others in the field think that electronic sensors in paper are still far from the consumer marketplace.

    “I don't think it's going to happen.” said Roy Horgan. “You need a conductive surface. It could be 10 years out. What we are looking for are solutions that you can commercialize to­day.”

    Solar Print is partnering with Italian automaker Fiat to develop a unique auto-glass with tiny photostatic cells（光电）that can capture electricity from the sun. In the meantime, using paper to conduct electricity is still a “blue-sky” project.

    “I would love to see someone prove me wrong, because that means that it's actually happening.” Horgan said. “If someone comes up with conductive paper, then that's a very interesting technology.”

    Whether you have a piece of land or a few pots on a balcony, plant a family garden: You'll all live healthier! Gardening is an easy activity to share and you'll harvest benefits along with your fresh vegetables, colorful flowers, and aromatic herbs. Even better, you don't have to wait for your plants to bloom to see those benefits.

    When parents and kids work together to plant and care for a garden, they can all enjoy these benefits:

    Physical activity: Gardening and yard work are mild exercise, which we all need every day (for at least 30 minutes). While tending your family garden doesn't require the intense activity of running or playing singles tennis, it's still beneficial to your health. For one thing, research shows that once you start gardening, you usually continue for more than 30 minutes. And gardening combines delicate skill strengthening and stretching.

    Lower stress, better mood: Gardening is excellent stress relief for good reasons: enjoying fresh air and sunlight, performance of relaxing tasks, and even contact with harmless bacteria in the soil that helps release serotonin (血清素) in the brain.

    Outdoor time: Children prefer spending a lot of time indoors, which can negatively affect their behavior and health. A family garden gets them outside enjoying and experiencing the natural world.

    A new study of 8,000 young people in the Journal of Health and Social Behavior shows that although love can make adults live healthily and happily, it is a bad thing for young people. Puppy love(早恋)may bring stress for young people and can lead to depression. The study shows that girls become more depressed than boys, and younger girls are the worst of all.

    The possible reason for the connection between love and higher risk of depression for girls is “loss of self”. According to the study，even though boys would say “lose themselves in a romantic relationship”, this “loss of self” is much more likely to lead to depression when it happens to girls. Young girls who have romantic relationships usually like hiding their feelings and opinions. They won't tell that to their parents.

    Dr Marianm Kaufman，an expert on young people problems, says 15% to 20% young people will have depression during their growing. Trying romance often causes the depression. She advises kids not to jump into romance too early. During growing up, it is important for young people to build b friendships and a b sense of self. She also suggests the parents should encourage their kids to keep close to their friends, attend more interesting school activities and spend enough time with family.

    Parents should watch for signs of depression—eating or mood changes—and if they see signs from their daughters or sons, they need to give help. The good news is that the connection between romance and depression seems to become weak with age. Love will always make us feel young, but only maturity(成熟)gives us a chance to avoid its bad side effects.

    It's OK to say you've never heard of grime (伦敦地下音乐) - unless you're from the UK. That's because this music type was invented in the UK in the early 2000s.

    To someone who's not familiar with underground music culture, it's easy to get confused between hip-hop and grime since they are both noisy. And many people didn't bother to tell them apart，until earlier this month when grime stars like Stormzy and J Hus led this year's Mobo – “music of black origin”, an award in the UK. Just like UK electronic music and hip-hop, from which grime drew influence, it mostly reflects the thoughts of young people. But different from hip-hop, grime singers sing in dialects with strong accents, giving a special flavor to their songs.

    Lady Leshurr，known as the “Grime Queen”, said that she once tried to hide her accent, as she didn't want people to judge her. But one day, she realized that she didn't need to change herself just to please others. And there's no doubt that this is the soul of grime music: be yourself.

    Grime has challenged modem music in its production beauty and its expressions. Also different from the hip-hop culture, which usually focuses on being rich, grime singers pay more attention to social phenomena like those who suffer from disasters and the gap between the rich and poor.

    Although still quite a young music type, grime seems to be getting loved by more and more people. In 2016, the English grime artist Skepta won the Mercury Prize with his album Konnichiwa, beating big names like David Bowie and Radiohead.

    However, no matter whether grime is one day accepted widely or not, one thing is for sure: in grime, singers always stay true to themselves.

    Last week, Vodafone started a test of the UK's first full 5G service, available for use by businesses in Salford. It is part of its plan to trial the technology in seven UK cities. But what can we expect from the next generation of mobile technology?

    One thing we will see in the preparation for the test is lots of tricks with the new tech. Earlier this year, operators paid almost £ 1.4 billion for the 5G wavelengths, and to compensate for that cash, they will need to catch the eye of consumers. In September, Vodafone used its bit of the range to display the UK's first hologram (全息) call. The Manchester City captain Steph Houghton appeared as a hologram in Newbury. It isn't all holograms, however: 5G will offer faster internet access, with Ofcom (英国通讯管理局) suggesting that video that takes a minute to download on 4G will be available in just a second.

    The wider application is to support connected equipment on the "internet of things" -not just the internet-enabled fridge that can reorder your milk for you, but the network that will enable driverless cars and delivery drones (无人机) to communicate with each other.

    Prof William Webb has warned that the technology could be a case of the emperor's new clothes. Much of the speed increase, he claims, could have been achieved by putting more money in the 4G network, rather than a new technology. Other different voices have suggested that a focus on rolling out wider rural broadband access and addressing current network coverage would be more beneficial to the UK as a whole.

    Obviously, 5G will also bring a cost to consumers. It requires a handset for both 5G and 4G, and the first 5G-enabled smart phones are expected in the coming year. With the slow pace of network rollout so far, it is likely that consumers will end up upgrading to a new 5 G phone well before 5 G becomes widely available in the next couple of years.