【推荐3】At first glance, there is nothing unusual about the BingoBox store—shelves stacked with snacks line the walls, tempting passers-by through the glass windows. But on closer inspection, BingoBox is no ordinary store. The door opens only after customers scan a QR code to enter, and there is no cashier to tally up purchases—just a lone checkout counter in a corner. The Shanghai-based company is one of many unmanned store operators opening outlets all over China, hoping to improve slim profit margins in the retail business by reducing staff costs.

“If capital costs rise quickly, that puts greater pressure on low-margin businesses like convenience stores and supermarkets,” said Andrew Song, an analyst at Guotai Junan Securities. “In China, manpower costs have been rising relatively quickly.”

However, the futuristic vision of shopping without a checkout person is still in progress. A reporter who visited a BingoBox store in Shanghai was briefly locked in when he was trying to exit without making a purchase. Although a sign near the exit stated that empty-handed customers can leave by scanning a QR code, no QR code was to be found. Repeated calls to the customer service hotline went unanswered.

Another unmanned operation in China, Take Go, only allows one customer in the shop at a time because of technology limitations in using multiple cameras for scanning customers’ faces.

The idea of unmanned stores first caught the world’s attention when the largest US online retailer announced its cashier-less store, which is only available to employees for now. Since then, some technology companies in China, including the e-commerce firm Alibaba Group, have launched their own versions of unmanned stores.

Embedded with technology such as RFID tags, mobile payment systems and facial recognition systems, such stores collect valuable data that give operators a better idea of consumers’ preference and buying habits, which can then be used to optimize the operation and make more efficient inventory decisions. For BingoBox, lower operating costs also mean it can afford to expand its reach to areas with less foot traffic, according to Chen Zilin, the founder and CEO of BingoBox.

【推荐1】Beginning 2020, the fifth generation of wireless technology is expected to be widely used throughout the world. The new network, called 5G, promises to give faster speeds and a higher capacity for the use of more devices. However, while some companies are competing to be the first to deliver 5G to the consumer, the environmental influences of the new network are being overlooked.

There is some evidence that the new devices and technologies associated with 5G will be harmful to ecosystems. The main component of the 5G network that will affect the earth's ecosystems is the millimeter waves. The millimeter waves that are being used in developing the 5G network have never been used at such scale(规模)before. Studies have found that there are some harms caused by these new technologies.

The millimeter waves, specifically, had a detrimental effect on birds. In a study, researchers observed that after exposure to radiation from a cell tower for just 5~30 minutes, the eggs of sparrows were disfigured. The disfiguration of birds exposed for such a short amount of time to these frequencies(频率)is significant considering that the new 5G network will have a much higher density(浓度)of base stations(small cells) throughout areas needing connection. The potential dangers of having so many small cells all over areas where birds live could threaten their population's survival.

Additionally, it was found that cellular devices were linked to many disturbances in the ecosystems of bees. In this study, beehives exposed for just ten minutes to 900MHz waves fell victim to colony collapse disorder(蜂群崩坏症候群). Bees are an incredibly important part of the earth's ecosystem. Around one-third of the food produced today is dependent on bees for pollination(授粉), making bees are a vital part of the agricultural system.

The impact that the cell towers have on birds and bees is important to understand, because all ecosystems of the earth are interconnected. If one component of an ecosystem is disrupted the whole system will be affected.

【推荐2】During the winter in the Southern Hemisphere, a blue point of light shines overhead. The brilliant point on the sky, which looks like a bright star, is actually two stars in close orbit — accompanied by the closest known black hole to Earth.

The newly discovered black hole is about 1,011 light-years from our solar system in the star system HR 6819. Published today in Astronomy & Astrophysics, the object is locked in an orbit with two visible stars. It is estimated about four times the mass of the sun and about 2,500 light-years closer than the next black hole. “It seems like it’s been hiding in plain sight,” says astronomer Kareem El-Badry, a Ph.D. student at the University of California, Berkeley, who specializes in binary star (双子星) systems but wasn’t involved with the study. “HR 6819 is such a bright star (system) that people have been studying it since the 80s, but it seems like it’s had some surprises.”

“If you find one that is very close to you, and you assume you’re not special, then they must be out there everywhere,” says lead study author Thomas Rivinius, an astronomer at the European Southern Observatory (ESO) in Chile. Researchers have long estimated that the Milky Way is home to hundreds of millions of black holes, objects whose gravitational fields (引力场) are so strong, not even light can escape. But finding these dark objects has proven extremely difficult. Dozens of black holes in the galaxy have been spotted “feeding” on nearby clouds of gas — a process that sends out x-rays as the material moves around the edges of the black hole. But the majority of black holes in our galaxy cannot be seen, so the only way to find them is by observing their gravitational effects on surrounding objects.

In follow-up work, researchers led by study co-author Petr Hadrava aim to study the light given off by HR 6819 and understand the precise identity of the two close stars.

【推荐3】Nowadays, handwriting seems to become less necessary, for young children learn to tap and touch screens before they have even learned to pick up a pencil or tie their shoelaces. Most of our written communication is done through texting on mobile phones or typing on a keyboard. And voice recognition softwares are becoming more and more advanced —making even keyboards unnecessary!

So, are handwriting skills important to your child? Actually, handwriting is an exercise in eye-hand coordination (协调), an important part of visual-motor (视觉运动) skills, which are connected with achievements in study. Scientists found that developing fine visual-motor skills in early childhood can lead to not only writing success, but better performance in reading and math in elementary school. It was also found that kids who fail to write neatly and efficiently are often accused of being lazy, and this may affect their behavior and self-worth. Moreover, a study showed that when a group of children were asked to come up with ideas for an article, the ones with better handwriting were more active and had quicker minds. In some ways, handwriting helps their brains’ development.

The first attempts at writing can be challenging for pre-school children —whose fine motor skills are not yet fully developed. But some skills to prepare for handwriting are simple to build at home and in preschool. Parents should provide lots of opportunities for kids to copy and draw shapes and simple pictures in early childhood before letters are introduced. Let your child copy your shapes in sand, or with chalks on a board before trying to draw the shapes on their own. Encourage your child to spend less time on electronic devices and more time on activities to improve eye-hand coordination.

Let’s face it —technology is certain to continue developing and more research is needed to find the best ways to teach handwriting to young children. But, there’s plenty of evidence that the handwriting practice can provide young children with a good start in developing skills needed for a healthy and successful journey in school.