My arms shook. The bow was almost as tall as I was, and it was equipped with an arrow, ready to be shot. Never had a more ill-suited person handled a weapon. But my editor had sent me on a mission: to find my inner Katniss Ever deen at one of Beijing's indoor archery clubs.

    The brilliant archer Everdeen is the lead character in The Hunger Games movies, the final of which was just released in cinemas. Her arrows can hit almost anything: sword-swinging enemies, fierce animals, even aircraft some-how. Me? I can't throw a paper ball into a trashcan with any precision. And I was warned that archery would require a great deal of upper body strength, though I hadn't seen the inside of a gym in years.

    News outlets like the New York Times and NPR have reported an increase of interest in archery, thanks to movies like The Hunger Games, Brave and The Avengers. Archery clubs have showed up in many major cities. In Jian Club, an archery-themed bar, we paid 120 yuan for an hour's worth of target practice and prepared our bows and arrows.

    We were told to stand sideways, with one shoulder facing the bull's eye. Your weaker arm would hold the bow, while the other would pull the bowstring back until the arrow was right next to your face. Then it was meters away.

    Well, sort of. Instead of sending the arrows whistling through the air, my first few simply dropped onto the ground.

    The failure was a good reminder that archery is a demanding, Olympic-level sport. It worked muscles in my back and arms that I just didn't have yet. An hour came and went, and I found myself leaving with a couple pierced (刺穿的)bull's eyes and sore shoulders. Was I ready to shoot down aircraft with a swift arrow? Not quite. But I was definitely ready for a return trip.

    Researchers say getting a good night's sleep is probably the best tool for memory and learning. But short periods of sleep may help our brains work better, says a recent study on napping. And taking a nap  may also help old adults fight off age-related memory loss.

    CDC, an American scientific organization, found that 50 to 70 million Americans have chronic（长期的）sleep disorders. So, someone who naps as a way of paying off a sleep debt may not experience the same improvements from napping as a well-rested person would. Also, that only children, the very old, sick or  lazy people nap is not an uncommon opinion.

    Researchers recently looked at information provided by nearly 3,000 Chinese adults, aged 65 years or older, to learn if napping after a mid-day meal had any effect on the mental performance of the subjects.

    First, they asked the people if they napped and for how long. Then, based on their answers, researchers put them into four groups: non-nappers (0 min), short nappers (≦30 min), moderate nappers (30-90 min), and extended nappers (≧90 min).  Nearly 60% of the people said they did take a nap after lunch and that   their naps lasted anywhere from 30 to 90 minutes. Most of the subjects said they napped for about an hour.

    The study found that people who took an hour-long nap did much better on mental tests than those      who did not nap. The hour-long nappers also did better on the tests than those who napped for shorter and longer periods. In this study, it seemed that the most effective nap lasted for about an hour, but not much longer.

    Yet Doctor Michael Twery notes that an hour long nap may be too long for young, healthy adults. 30 minutes is enough to remove the pressure to sleep and will help us feel more awake.

    Environmental experts warn that our planet is drowning inplastic.

    The world's cities produce 2 billion tons of trash everyyear. By the year 2050 that number is expected to rise to 3 billion tons. TheWorld Bank estimates that the largest amount of trash today, about 44 percent,is plastic. But we often have to buy packaged goods. And often that packagingis made of plastic.

    Now, that may be changing. A new environmentally-friendlyshopping model was recently launched at the World Economic Forum in Davos,Switzerland. This shopping model, called Loop, aims to replace throwawaycontainers with reusable ones.

    Loop is the idea of Terra Cycle, an American-based recyclingcompany. Its chief, Tom Szaky told the Associated Press (AP) that "removingplastics from the ocean is not enough." He said the point is to get awayfrom single-use packages. Szaky said that Loop is the future of shopping. Butit comes from an idea of the past.

    He compared it to the "milkman model" of the 1950sin the United States. Back then, someone brought milk to your doorstep in glassbottles and then left with empty bottles. These could be cleaned and used again.The result is zero-waste.

    Jennifer Morgan from the environmental non-profitorganization Greenpeace also joined in the discussion about Loop at Davos. Shesaid that "Greenpeace welcomes the aim of the Loop Alliance to move awayfrom throwaway culture and disposability." But Morgan questioned whethercompanies worldwide are ready to change their business models.

    Loop is set to launch later this year in three eastern U.S.states, and also in Paris, France and some of the surrounding area. Then Loopplans to expand to the U.S. West Coast, Toronto, Canada and Britain by the endof this year or 2020.

    Back in 1988, I was working at the University of Bonn in Germany as a research fellow. I took some time off in early May to visit a friend, who was the director of a museum in Viterbo, in central Italy. I set out by train, which crossed the Swiss border to reach Zurich, winding through valleys and along hillsides, and entering tunnels and making its way through the Swiss Alps. The scenery was so beautiful.

    The train then crossed the Italian border before passing through Milan and Florence, then finally stopping in Rome. I was lucky, as my hotel was close to the railway station. The next morning, I had a coffee at a nearby café and eagerly set out to visit as many of the famous Roman landmarks as possible.

    The following day I headed back to the train station, intending to take a short train ride to Viterbo to meet up with my friend. When I arrived at the station and attempted to locate the correct platform, I quickly realized that the station was closed for an upgrade (升级). For a moment my mind went blank and did not know what to do. My biggest problem was my luggage—my suitcase and hand luggage were so heavy that I couldn't move about easily. As I don't speak Italian, I could not ask anyone for instructions. I dragged my suitcase about 100 meters to a nearby motor mechanics. A tall, strong man of about 50 years of age was working there and I excused myself and asked where the nearest station was. I am sure that he did not understand me properly but he could easily guess that I was looking for a station. He replied, but I did not understand.

    He smiled, wiped his hands and said something, which I guessed to mean "come along". So I dragged my suitcase along and followed him. He opened the door of his car, motioned to me to get in and then drove for a few minutes to the next station. I got out, unloaded my luggage, then shook his hand with thanks. He smiled back and drove away.

    There was no time to hug or exchange names  I understood he was busy and in the middle of his work. I was moved so much by his generosity that I have never forgotten him.

The coast of the State of Maine is one of the most irregular in the world. A straight line running from the southernmost coastal city to the northernmost coastal city would measure about 225 miles. If you followed the coastline between these points, you would travel more than ten times as far. This irregularity is the result of what is called a drowned coastline. The term comes from the glacial (冰川的) activity of the Ice Age. At that time, the whole area that is now Maine was part of a mountain range that towered above the sea. As the glacier declined, however, it applied enormous force on those mountains, and they sank into the sea.

As the mountains sank, ocean water charged over the lowest parts of the remaining land. And the highest parts of the former mountain range, nearest the shore, remained as islands. Marine fossils found here are 225 feet above sea level indicating the level of the shoreline prior to the glacier.

The 2,500-mile-long rocky and jagged (锯齿状的) coastline of Maine keeps watching over nearly 2,000 islands. Many of these islands are tiny and uninhabited, but many are home to blooming communities. Mt. Desert Island is one of the largest, most beautiful of the Maine coast islands left behind by the glacier. Measuring 16 miles by 12 miles, Mt. Desert was very nearly formed as two distinct islands. It is split almost in half by Somes Sound, a very deep and very narrow stretch of water seven miles long.

For years, Mt. Desert Island, particularly its major settlement, Bar Harbor, has afforded summer homes for the wealthy. Recently, though, Bar Harbor has become a new arts community as well. But the best part of the island is the unspoiled forest land known as Acadia National Park. Since the island sits on the border between two different geographical zones, the park supports the plants and animals of both zones. It also lies in a major bird migration lane and is a resting spot for many birds.

A lunar crystal (水晶) was found in lunar basalt particles (玄武岩颗粒) collected from the moon in 2020 when the Chinese moon mission landed in Oceanus Procellarum, returning with more than 1.7 kg of lunar samples delivered safely to the Earth. 

The crystal found on the near side of the moon is giving scientists hope of providing limitless power for the world forever. It is made of material previously unknown to the scientific community and contains a key ingredient for the nuclear fusion (核聚变) process, a form of power generation that uses the same forces that fuel the sun and other stars. It is transparent and roughly the width of a single human hair, and it formed in a region of the moon where volcanoes were active around 1.2 billion years ago. 

One of the primary ingredients found in this crystal is helium-3 (氦-3) , which scientists believe may provide a stable fuel source for nuclear fusion reactors. The element is incredibly rare on the Earth, but it seems to be fairly common on the moon. China's next moon mission is expected to be carried out by Chang'e 6 in 2024, which will attempt to collect the first samples from the far side of the moon, which never faces the Earth. 

Although it is too early for scientists to have made financial estimates on such a fuel source, it will undoubtedly be extremely costly. There is, of course, the matter of bringing the crystals back from the moon, especially in large amounts that are needed to fuel fusion reactors. 

Helium-3 produces significantly less radiation and nuclear waste than other elements. The current nuclear fusion process has raised serious safety concerns, and as a result, scientists have been searching for a way to create nuclear power from nuclear fusion. During the fusion process, radioactive waste is not produced, potentially making a securer and more efficient fuel source. 

Around 25 tons of helium-3 could power the US for a year. Multiple private companies and countries with space agencies have signaled their intentions to mine the moon for helium-3, and this latest discovery could kick start the race.