【推荐2】There was a time when a trip to the supermarket in the United States often ended with a seemingly simple question from the cashier, “Paper or plastic?” Well, which type of bag would you choose?

While both types of bags have some influence on the environment, it has long been supposed that paper bags are better. They are made from a renewable source, are broken down easily, burn without giving off thick smoke and can be recycled. However, the producing process behind paper bags uses more energy than that of plastic ones. How can this be true?

Studies show that paper bag production requires four times as much energy as plastic bag production. And the amount of water used to make them is twenty times larger. Besides, the influence on forests is very serious. It takes about fourteen million trees to produce ten billion paper bags, which happen to be the number of bags used in the United States yearly. In terms of recycling, the idea that paper bags are more environment-friendly than plastic ones can be quickly discarded. Research shows it requires about 98% less energy to recycle plastic than it does to recycle paper.

Even though paper bags might be more harmful than plastic ones, plastic still seems to be considered as the more harmful of the two by governments. In Ireland, for example, a tax has been introduced to discourage the use of plastic bags. People have to pay 22 cents for every plastic bag, and as a result, their use has dropped quickly.

There’s no doubt that it makes more sense to reuse these bags. However, we don’t seem to be doing that at present. That may be because they fall apart quickly. If so, cloth bags are a better choice, but still, their production also has a bad influence on the environment. So what to do? How should we answer the question of “Paper or plastic?” It seems that we first need to ask ourselves one more general question: “What can I do to help the environment?”

【推荐1】5G wireless networks are ready to power the cities of tomorrow. However, exact implementation (实施)of 5G will vary from city to city, with each city having its own unique set of priorities, requirements, and objectives.

Since 5G enables countless service possibilities, cities must develop strategies around their specific needs. Business and civic leaders play a decisive role in this process, helping to drive smart city initiatives and ensuring that key infrastructure (基础设施)elements are in place.

Several urban areas, including Los Angeles, Dallas, Houston, Atlanta, and Chicago, are early to benefit from 5G For operators, these large urban centers offer a critical mass of solid infrastructure to support 5G’s complex technology requirements.

Now, regional and local governments play a critical role in positioning their cities to become early 5G adopters. They have a growing responsibility to streamline the permitting process, change fee structures, and minimize regulator hurdles in order lo enable greater 5G implementation.

Efforts are already in full force by industry players to overcome challenges for a smooth build-out in areas where 5G is needed first. As business leaders take a more active role in ensuring that they are well-positioned to better 5G services, they also increase their ability to transform their organizations into smart companies. Peter Linder, head of 5G marketing for North America at Ericsson, emphasizes the critical role individual leaders can play in making 5G and smart cities a reality. “5G will be introduced in urban areas first, driven by consumer and business’s needs,” he says. “Proactive city leaders appreciate the potential value of 5G for developing smart city solutions and will partner with service providers to speed up vital network development.”

The role of business and civic leaders as stimulators for encouraging 5G adoption is decisive to creating smarter, safer, and cleaner cities. The time is right for urban leaders and business executives (执行官)to work together toward making smart cities a reality.

【推荐2】The war epic The Battle at Lake Changjin, one of the most expensive films ever made in China, shot to the top of the week-long National Day holiday box office, promoting the domestic market to recover after an unsatisfying box office for more than two months.

Set in the War to Resist US Aggression and Aid Korea (1950-1953) and headlined by Wu Jing and Jackson Yee, the film tells the story of the Chinese People’s Volunteers soldiers fighting bravely under freezing temperatures in a key campaign at Lake Changjin, or Chosin Reservoir.

With the number of cast and crew reaching an unprecedented scale of more than 12,000, the movie re-creates the serious conflict on the Korean Peninsula amid the extremely cold winter of 1950, when temperatures decreased to the lowest level in 50 years. The movie’s production involved more than 80 visual-effects companies domestically and abroad, with the script revised 37 times.

Breaking over 10 records, including single-day income for a film, the blockbuster has earned around 2 billion yuan ($310 million) since its opening on Sept 30. It accounted for percent of total holiday receipts, which had reached 2.67 billion yuan as of Monday, according to the movie information tracker Beacon.

The film has also gained millions of reviews and clicks on several of the country’s most popular social media platforms, including Sina Weibo and Douyin, with most commenters praising the heart-breaking tale and saying it stirred their national pride, making them want to pay tribute to the CPV heroes who sacrificed their lives. Some netizens said the film reminds them, amid the current China-US tension, to cherish today’s peaceful life.

【推荐3】Have you ever heard of invisible ink? You may have seen it in movies. When light is shone on the paper which invisible ink is written on, you can read it!

As magical as this seems, the change in color is due to science. The ink is absorbing higher energy light and giving lower energy light. This reaction is an example of fluorescence（荧光）.

Light is a very broad term that describes a range of electromagnetic rays, including gamma rays, infrared light（红外光）and ultraviolet light. One part of the electromagnetic visible light is the colors that we can see with the human eye. These rays travel in curvy lines and each type of the ray is characterized by a different wave pattern. For example, Gamma rays have a shorter wavelength than infrared light. Shorter wavelength is connected with higher energy, so gamma rays also have more energy than infrared light.

Corals（珊瑚）are animals that live underwater. And the corals in the Red Sea exhibit fluorescence. Why is this happening? Scientists have shown that fluorescent objects absorb higher energy light and release lower energy light. Since the corals of the Red Sea are deep in the water where there is very little visible light, scientists theorize that these corals absorb ultraviolet light and produce visible light. They have special photo proteins, which enable them to change invisible light to visible light.

Fluorescence is not just used to create pretty colors. Corals have developed photo proteins for a biological reason. The visible light is used by algae（海藻）, which are eaten by the coral, to make food through photosynthesis（光合作用）. The visual character of these photo proteins could also be used for biomedical research. They can highlight cells and cell structures under a microscope.

Isn't it amazing that a simple organism that we don't think very much of is not only grand but could also have so many potential uses in medical research!

【推荐1】New research found that people facing stay-at-home orders tried cooking new things and threw away less food. The results came from a recent research project involving 11,000 shoppers in 11 countries. It showed that people were buying less microwaveable food and more fresh fruits and vegetables.

The study involved shoppers in several European countries, as well as Australia, Chile, Uganda, Canada and Brazil. In nearly half of the countries, shoppers reported buying fewer salty or sweet snacks, although overall sales remained about the same.

Charlotte De Backer, a lead organizer of the study, who was a researcher at the University of Antwerp in Belgium, said many people turn to salty, sweet and fatty products when they are feeling stress. But during the current crisis－Coronavirus (冠状病毒), many people seemed to fill this desire with home-baked goods. In Chile, for example, there was a large drop in sales of snacks, but a big rise in people buying baking necessities like flour.

De Backer said the healthier food buying could be related to the fact that people took more time to carefully plan their trips to the store. “If you make a shopping list, you plan your meals ahead and you are less likely to add unhealthy food.”

Many shoppers taking part in the study also said they had tried cooking new things and used more left-over foods to reduce waste. However, De Backer said this behavior could be linked to fears of food shortages and could change after the Coronavirus .

But she noted that some of the improvements in eating are likely to continue. She says this is because in many countries, stay-at-home orders have been in place for more than six weeks – the usual amount of time it takes people to form new behaviors.

De Backer also said that as people grow more confident and creative in the kitchen, they could break down one of the main barriers to home cooking.

【推荐2】When in space, astronauts typically eat dehydrated (脱水), nutrient-rich food, but when it comes to longer space missions, that can become a problem as they'll eventually lack nutrients from fresh vegetables. However, Ying Diao, a chemical and biomolecular engineering professor will be researching ways astronauts can grow their own fresh vegetables more efficiently during space missions.

Diao's goal for this research is to develop wearable sensors for plants so that their health and stress levels are detected autonomously, with no need for humans to do the testing. Then, a “smart” plant chamber will be developed that can identify the best conditions for a plant to grow in to reduce its stress. Diao also wants to develop another sensor that will continuously monitor a plant's growth over its lifetime. “We're helping the astronauts to be more healthy during space missions, by improving the health of the plants they grow,” Diao said. “So the bigger impact could also be that it helps future human colonization on Mars or on other possible habitats.”

Although the ultimate goal for this project and research is to help people in space, it could also be used back on Earth in addressing climate change.

“During climate change, a plant experiences a lot of stress, but we need a plant to be more productive without increasing the footprint of the agriculture land to feed the growing population of our planet,” Diao said. “To address this conflict, we could potentially help decipher(破译)how the climate change and the microenvironments are impacting the plant stress and then we are better equipped to help plants adapt to a changing environment.”

“Most of the technology in my field is developed for human health but we've been ignoring plants for too long,” Diao said. “I think it's a new frontier that I want to go into and it is just part of a smart agriculture movement.”

【推荐3】Utility, Portland's low-waste, refill and reuse company, started in January 2019 and held its first retail (零售) shop in April. Rebecca Rottman and Nadine Appenbrink, two women on a mission to green their city, are deeply committed to sustainability (持续性) and supporters of zero waste.

They believed that their green-minded city was missing something that was essential to sustainability. So, they started one shop (that is almost zero waste) as a second job for both. It started as a personal journey, looking for clean products that didn't come in plastic. Their mission is to reduce the amount of single plastic use by allowing people to bring their own reusable containers.

Every week the women teamed up with local stores to sell their goods and to refill products for returning customers. Now they are operating only online for pickup or local delivery in the Portland area. It's really easy. Just shop online and choose a container. Then select pickup or delivery. The products include all-natural dish bar soap — that is locally made and a wide variety of plastic-free kitchen tools. While not completely zero waste, Utility is striving to get incredibly close. Appenbrink said, “We’re all on a journey. And we want to be as approachable as possible. Utility is to raise awareness about this lifestyle.”

When the shops were running, the women were able to build community with other like-minded environmental activists and they planned to do community engagement activities like park cleanups. There are also plans to start some DIY classes on how to make natural products like the face cream they sell.

There are zero waste or as close as possible stores in other communities, like Clean Kilo in Birmingham, UK, but they are real brick buildings. Utility's concept is so simple that it can be copied almost anywhere. Zero waste markets are the way to go to transition (过渡) into the economy that is needed to stop plastic waste, reduce our carbon footprint and have a sustainable future.

【推荐1】I think that I always knew I wanted to become an artist. I can’t remember a time when I wasn’t drawing or painting pictures. My oldest sister and my brother were artistic, and watching them draw fascinated me. They had many different art supplies around the house. Boxes of pastels, little ink bottles and pens were very appealing.

My parents and friends soon saw that I had more than a passing interest in art. It came to define much of my image. Relatives gave me art-related birthday gifts. At school I became “the kid who could draw,” a unique distinction, like “brainiest” or “best athlete”.

As I got a little older, I began copying pictures: cartoons, comic books, and magazine illustrations.

My third-grade class wrote essays on what we wanted to be when we grew up. To me it was obvious. We read them aloud, and I told about the types of paintings I would some day try. I’d have turtles with paintbrushes tied to their backs walking around on a big sheet of paper. Or I’d fill squirt guns with different colored paints and shoot at the canvas. I actually tried this with friends! Well, it sounded like a good idea.

One of the only discouraging childhood experiences about my artwork happened in the fourth grade. During study time I was drawing a picture. My teacher took it away and wrote an angry note home to my mother. “David would rather be drawing pictures than doing his work!!!” I couldn’t believe it, three exclamation points. School “art classes” were pretty uninspiring. Art never seemed to be taken as seriously as other subjects.

In the eighth grade, a big career day was held. Months before, we wrote suggestions for careers we wanted to hear about. On the big day, guest speakers from many fields came to talk, but there wasn’t one that came close to an art-related field.

In high school it actually sank in that I was going to be an artist. I already knew. I’d always known. My parents were excited about my choice, too. As I looked into art schools, I felt like doors were being thrown wide open. Until then my art was a private thing, but at art school I found a place where everyone as “the kid who could draw.”

【推荐2】I hardly have any good memories of my summer holidays two years ago. All I can remember is that I was busy doing drugs with my friends for most of the time. I said to myself that I would give up drugs before I went back to school，but when school started I was still addicted to them.

I went back to school like the other students but I had become a very different person. Most students came back to school with smiles on their faces，but not me. I became a different person that didn't care about anything but drugs. It was like I was walking around in a different body.

I went from being an above average student to a really bad student. I started to do things that I never thought I would do before -like bullying（恐吓）students，and fighting with people just because they looked at me in the wrong way. I rarely smiled or played sports like I used to. I was always moody and angry with my friends and teachers. I started to skip school（逃学）once or twice a week. No one seemed to care，so I was soon absent nearly everyday. I started stealing money from my parents and I lied to other people just to get some money for drugs. When my parents found out that I stole their money and sold their jewellery, they got really angry. I started to hang out with my drug addict friends for days and nights without going back home. I even slept by the side of the road and woke up without caring what people would think about me.

Now I have changed a lot. Drugs are terrible. Stay away from them.

【推荐3】Lucky is the man who has no “skeleton in his closet.” When a man has done something in his life that he is ashamed of, that he wants to hide, he is said to have a “skeleton in his closet.” Some people may have more than one skeleton.

As we have noted many times, it is hard to find out how these expressions begin. Sometimes, we get some hard facts. But more often we have to depend on guesswork. And that is true of this phrase, which came from England.

Before 1832, English law did not permit a doctor to cut open a dead human body for scientific examination, unless it was the corpse (尸体) of an executed (处决) criminal.

But when it became legal, more and more doctors demanded skeletons for a more scientific study of medicine. It was helping in the advance of modern medicine. The demand had become so strong that men began to rob tombs and sell skeletons to doctors at high prices.

We are told that a doctor would usually buy just one skeleton for scientific study. It became very important in his work. But he had to keep it hidden because most people objected to keeping such a thing. As a rule, the doctor keep his skeleton in some dark corner where it could not be seen, or hide it in a closet.

After a time, people began to suspect every doctor of hiding a skeleton in the closet. From this suspicion, the phrase “a skeleton in the closet” took on a broader, more general meaning: to describe anything that a man wanted to keep others from discovering. It could be proof of a criminal act, or something much less serious. Well, that is one theory.

One writer, however, believes that the phrase might have come from something that really happened. It is his guess that a hidden closet in some old English country home may have turned up a real skeleton, clear proof of some old family shame or crime. Well, one man's guess is as good as another. But this sounds like a story by the great French novelist, Balzac.

Balzac tells us of a man who suspected his wife of having a lover. The husband comes home by surprise. But she hears him and quickly hides her lover in the closet of her bedroom. He enters her room and asks her if she is hiding her lover. He says he will not open the door to the closet if she promises him there is no one there; He will believe her. She answers firmly that she is not hiding anyone in the closet.

The husband then begins to build a solid brick wall against the closet. His wife watches, knowing that her lover will never come out alive. But she will not change her story and admit her guilt.