1 . Just as a hungry brain craves (渴望) food, a lonely brain craves people. A new brain study demonstrates this. After being left alone, it shows people's brains would be activated at the sight of other people. The action was in the same brain region that speeds up when a hungry person sees food.

Livia Tomova, a neuroscientist, who studies how the brain produces mental activities, and her colleagues began this study. They recruited (招募) 40 people. On one day, the participants had to fast—not eat anything at all—for 10 hours. On another day, the same people were placed in a room for 10 hours. They couldn't see anyone. No friends, no family and no social media. They weren't even allowed to check their email. After both days, Tomova and her colleagues put the people in a MRI machine. It shows activity in the brain by tracking how much blood is flowing to each region.

At the end of each day, the participants showed high activity in a brain area called the midbrain. The scientists were interested in two, small areas within it. Both areas produce dopamine, a chemical that is important in craving and rewards. The two areas activated when hungry participants saw pictures of tasty pizza or juicy hamburgers. After the volunteers had been isolated, those brain areas became active when they saw social activities they missed. It might be playing sports or chatting with friends.

The midbrain plays an important part in people's motivation to seek food or friends. In fact, it responds to food and social signals even when people aren't hungry or lonely. But hunger and loneliness increased the reactions and made people's responses specific to the thing they were missing. And the more hunger or isolation the volunteers said they were experiencing, the stronger the activity in this part of the brain. Tomova and her colleagues published their results November 23 in Nature Neuroscience.

2 . Babies who frequently communicate with their caregivers using eye contact and vocalisations(发声)at the age of one are more likely to develop greater languages skills by the time they reach two,according to new research.

In the study, researchers looked at 11- and 12-month-od babies' vocalisations. gestures and gaze behaviours ,and at how their caregivers responded to them.To measure he interactions ,the researchers videoed infants(婴儿)and caregiver at home,and asked them to play as usual.They took those recordings back to the university

The scientists then used statistical models to find that the best predictor of vocabulary at 24 months was when infants were seen to use vocalsatioms while looking at their caregiver's face when they were about a year old.The benefits were even greater when these interactions were followed by responses from the caregiver.

The statistics showed that at 19 months,children had an average of about 100 words.Those who exhibited the beneficial interactive behaviour earlier in life were seen to have an average of about 30 extra words.

"The message of this paper is that it is the result of a joint effort; noticing what your child is attending to and talking to them about it will support their language development." said McGillion, a co-author of the work.

"The joy of this message is that that can happen in any context... across any part of your day.It's not something that requires special equipment or even lots of time.I can happen when you're doing the laundry,for example—when you're taking out the socks, you can talk about socks...in the park, in the car, at mealtimes,at bathtimes.This finding can be used in any context,"added McGillion.

"This is a developmental snapshot in the first year of life, but children are constantly growing and changing and so are their behaviours. It would be interesting to look at these sorts of behaviours again as children progress through the second year of life to see what's happening there,"said Donnellan,the lead author on the study.

3 . Most solar panels acquire sunlight from only one side, meaning they can acquire more or less of it depending on where the sun is in the sky. In recent years, they’ve become far more effective typically turning around 22 percent of the light they acquire into energy. In a new study published in the journal Joule on Tuesday, scientists put forth a way to increase that percentage even higher: double-sided solar panels that can move to follow the sun.

Basically, these panels can acquire sun from not only their sun-facing side but also from the light reflected off the ground onto their dark undersides. At the same time, a GPS allows them to move on an axis from east to west in order to always be pointed at a best angle to acquire the sun’s rays. Though double-sided solar panels and sun-following solar panels are both in use currently, models that combine the two technologies aren’t widely available for commercial use, Solar experts predict explosive growth in the market soon, though.

The study authors determined that these two-sided sun-tracking panels produce an average of 35 percent more energy than immobile single-panel systems, and are 16 percent more cost-efficient. That holds true even when accounting for changes in weather conditions.

“This means that investing in double-sided and tracking systems should be a safe bet for the foreseeable future, Carlos Rodriguez-Gallegos,” the study’s lead author said.

The same warnings for solar panels and their effect on the local environment apply to the double-sided, moving systems as well, if not more so. Lead used in solar panels can be one source of local pollution, and Dustin Mulvaney, an associate professor of environmental studies, told Earther in an email double-sided panels could mean “twice as much lead” as traditional solar systems.

Since these new panels are more energy efficient, they could save not only money but also land. That would require restructuring how solar contracts currently work.

4 . An 85-year-old primary school constructed in 1935 in Shanghai has been lifted off the ground in its entirety and relocated using new technology called the “walking machine.” The project marks the first time this “walking machine” method has been used in Shanghai to relocate a historical building.

Urbanization（都市化）has continued to significantly threaten architectural heritage. In the capital Beijing, for instance, more than 1,000 acres of its historic hutongs and traditional courtyard homes were destroyed between 1990 and 2010.

In the early 2000s, cities including Nanjing and Bejjing-due to the critics’ protest about the loss of old neighborhoods-drew up long-term plans to preserve what was left of their historic sites, with protections introduced to safeguard buildings and restrict developers.

These conservation efforts have taken different forms. In Beijing, a near-ruined temple was transformed into a restaurant and gallery, while in Nanjing, a cinema from the 1930s was restored to its original form, with some additions providing it for modern use. In 2019, Shanghai welcomed Tank Shanghai, an arts center built in renovated（重修的）oil tanks.

“Relocation is not the first choice, but better than destroying,” said Lan, the Shanghai primary school’s project supervisor. “I’d rather not touch the historical buildings at all.” Building relocations he said however, are “a workable option.” “The central government is putting more emphasis on the protection of historical buildings. I’m happy to see that progress in recent years.”

Shanghai has arguably been China’s most progressive city when it comes to heritage preservation. The survival of a number of 1930s buildings and 19th-century “shikumen” （or “stone gate”） house have offered examples of how to give old buildings new life.

“We have to preserve the historical building no matter what, ” Lan said. “The relocation has challenges, but in general, it is cheaper than destroying and then rebuilding something in a new location.”

6 . Until now, scientists haven’t been able to study the new rock on the moon.The new samples from Chang’e 5 will change this. They’re from near Mons Rümker, a volcanic mountain where the rock is thought to be much younger-- about 1 billion years old.

There are a lot of reasons scientists are eager to study this younger rock, one of which is that it could help us more precisely date not only the moon, but many rocky planets and other objects.

Here’s how that works: Scientists date lunar rock by using something called a chronology curve（年代学曲线）, says Jollliff, a scientists at Washington University in St. Louis. Basically, they estimate the age of the rock by counting the number of craters（火山口） in the area the rock comes from; those increase as objects strike the rock over time. To make this estimation, scientists need to match the number of craters to a precise age. Right now, they only have data points for lunar rock that is 3 to billion years old. Modern techniques can date the new sample extremely accurately, and once scientists know its precise age, they can add a valuable data point to their chronology curve. The dating system will also help us more accurately estimate the age of all sorts of objects in space, like rocky planets and other moons.

Another reason scientists are keen to study this young volcanic rock is to find out more about how volcanism works on the moon. Jollliff says that it’s unclear why there was volcanic activity on the moon for such a long period of time. Most of the moon; s volcanic activity, he says, is thought to have occurred 3 or 4 billion years ago, when the moon was still pretty young. But since the moon does not have plate structure, which drives volcanism on Earth, it’s unclear what could have caused much later volcanic activity. “That’s something that you can find out of the samples by studying them in the lab,” Jollliff says.

7 . Anyone wanting to help the poor may like this idea—recycling aluminum cans in a different way, which is apparently also good for the environment. So you're actually killing two birds with one stone. It goes without saying that recycling aluminum cans can save resources, energy, time and money. People usually save and place aluminum cans in the dustbins, which are then collected and taken away by cleaners, who will finally recycle them in the recycling center. But if you save the aluminum cans, and skip the cleaners, you can save these same cans for something more important—helping the poor. In other words, by doing less, you are giving the environmental cause some new significance.

Here is how to put this idea into action. Take your aluminum cans and place them in a plastic bag. For the dirty ones, rinse them out first. Store the bag of clean aluminum cans. Once you collect about one hundred cans or more, take the cans to the recycle center yourself. There are about eighteen aluminum cans in a pound. And you can receive three to four dollars for one hundred cans. Donate your three to four dollars to the poor or any charity organization of your choice.

By now, you may wonder if your few dollars have really made a difference to the poor. Consider this: Is there any individual or any specific event that is great enough to change the world or decide the direction that history takes? The answer is probably no. What if there were a lot of people who would do the same thing? History shows nothing but the collective will of the whole community. And that will surely be powerful enough to make a bigger difference.

Go to your community or your school and spread your idea. Share your idea and save your aluminum cans with other people. One hundred people can speak louder than one. And the money you make by saving cans can be multiplied by one hundred times. And if more people join in the cause around the world, an even larger difference can be made , and more people in need will enjoy the benefits.

8 . If you want to do your kids a favor, consider having them walk to school. Walking to school provides many benefits – improving academic performance, reducing anxiety, boosting spirits, better sleep, a sense of independence, having an opportunity to familiarize oneself with a neighborhood, to notice small details, to feel a sense of wonder at the surroundings. The list goes on.

Parental fears still exist, however. Parents are terrified of cars, of injury, of harsh weather, of encounters with strangers and wild animals. These fears prevent parents from letting their kids do something that's actually enormously beneficial to them, despite the fact that removing an opportunity to be active contributes to an increase in childhood obesity, which can have a greater negative impact on a child's life than the risk of being injured due to being active.

How do we go from being a society that does not encourage its children to walk independently to being one that does? Parents must face their own discomfort with letting go. Brussoni, an expert who researches children's outdoor and risky play, said "We want to move parents from focusing solely on protecting their child to building trust in their child’s abilities and strategies to support their child’s skills in navigating the streetscape."

Schools can play a role by encouraging children to walk to school. Brussoni offers additional suggestions: "They should promote a culture that walking to school is the norm, help educate parents on why this is important, and consider closing the streets around the school to cars before and after school."

Parents might do well to put themselves in their children's shoes. As adults, we know how good a morning walk feels to start off a day or to end one. Walking energizes us and cheers us up, and it can do the same for children. As we go through this pandemic that has shaken up all of our lives, it's a good time to practice new routines and establish new habits. Walking to school is a great place to start.

9 . A number of people hold an optimistic attitude toward artificial intelligence's ability to reshape education nowadays. However, many feel such claims are overblown.

Kentaro Toyama, a professor at the University of Michigan School of Information, is one of those doubtful about the idea of using AI in the classroom.

Toyama mentioned a situation he encountered while working in an after-school program in digital literacy（数字技术素养）. He said, “In trying to teach students to use technology, the greatest difficulty is the technology itself." As soon as he looked away from the students, they would “very quickly find the most fun games they could find on the computer and start playing them”. That reveals the problem with putting too much faith in Al for teaching. “There is great potential for it to be a distraction." he said.

Toyama once surveyed a large group of people about their preference for the following educational situations: a school with no teachers but powerful AI, one with bad teachers but strong computers, one with good teachers but no computers, or one with great teachers and many computers. The result showed that nobody would send their children to a school with powerful AI but no teachers, or one with bad teachers but strong computers. Toyama concluded, "Good teachers are what matters; everything else is secondary compared to that."

Toyama is also concerned that AI and technology may widen the gap between disadvantaged schools and wealthier schools. He said, "In the case of schools, well-resourced schools will find the best ways to use technology. But if you' re in a school district that is underfunded and parents are not involved, it doesn't make a difference how good the technology is, and it will not turn that situation around."

When asked when schools should adopt AI, Toyama suggested that they should wait until the basics are in place, teachers want it, and the technology is proved to have positive educational values.

10 . On a scale of 0 to 10, I’d say my happiness ranks at about 6. I’m glad to know I’m a 6, because, as a famous management saying puts it, “You can't manage what you don’t measure.” If you want to improve an aspect of your life, you need to be able to assess progress toward your goal-and that means measuring it.

The goal of this column is to help you manage and improve your happiness. A number of people have asked me whether quantitative happiness measures are really accurate and reliable-and it’s a reasonable question. So let’s take a look behind the curtain. But not just for intellectual curiosity; as you will see, understanding the measurement of happiness can itself make you better at improving your own well-being-and avoid some critical errors.

The best method scientists have to understand with confidence how something affects something else is a randomized, controlled trial. Think of the tests currently under way to find a vaccine for COvID-19. They take a long time because the drug companies with trial vaccines are conducting experiments that randomly assign people to a treatment group they get the vaccine and a control group (they get a placebo), and then waiting to seif the drug is effective and safe by comparing the two groups after enough time has passed.

In the research on happiness, this usually isn’t possible. Want to know if people are truly happiest in Denmark, as some studies suggest, and test it with a randomized experiment? You would need to randomly take two groups out of their homes, move one group to Copenhagen, and the other to, say, Dayton, Ohio- but make sure they think it might be Copenhagen and never get the truth. Follow up a few years later to see who is happiest. Obviously, that’s ridiculous. So with randomized controlled trials largely not available to them, happiness researchers instead rely on self-reported happiness surveys, where large groups of people anonymously report their levels of life satisfaction. Then, the researchers use fairly complex statistical techniques to mimic（模拟）a controlled experiment in order to show how different aspects of people’s lives affect-or at least are associated with-their happiness.