【推荐1】Many animals need to move across large distances. Often they do this as part of their natural migration（迁徙）. Sometimes animals need to move to a new area when food gets low or conditions get worse. However, humans have taken over huge areas of the planet. Roads and highways cut up the remaining natural areas into many small sections, making it dangerous for animals to move.

Many people are working to help animals by creating “wildlife corridors（走廊）”, trying to reconnect smaller natural areas so that animals can move over larger areas. One important step in creating these corridors is building wildlife bridges and tunnels to give animals a way to safely cross dangerous roads. These changes don’t just help animals, but they also save human lives by avoiding accidents.

On China's Hainan Island, scientists created a bridge for gibbons, an animal that lives in southern Asia. But in 2014, natural accidents caused huge gaps in the forest, forcing them to make dangerous jumps. Scientists created a simple and cheap bridge, which solved the problem. In 2018, the experts in Utah, America built a wildlife bridge over the busy highway. A 4.8-kilometer fence was created to help guide animals to the bridge. Normally, animals take a long time to discover and begin using wildlife bridges, so experts didn’t expect the bridge to get much traffic for several years. However, to their surprise, many different kinds of animals have already used the bridge.

Now people in other countries are looking to try similar ideas. In Brazil, scientists want to create bridges to help animals cross the hundreds of miles of highway that cuts through the Amazon rainforest. In Uttarakhand, India, an eco-bridge made from all-natural materials has been built. Though it's high in the trees, it’s expected to help smaller animals on the ground by reminding drivers that they're in an important natural area with lots of wildlife. Already, the bridge has got a lot of attention, with many people taking selfies（自拍照）in front of it.

【推荐3】In 2019, a NASA satellite map with dark and light green colors showed the world that China is leading the increase in greening on Earth’s land area because of national tree-planting programs.

    1    over 45 percent of China’s land is covered with deserts and sandy soil, way bigger than China’s arable land (可耕地) which is nearly 10 percent of the total arable land in the world, but supports over 20 percent of the world’s population

March 12 marks China’s Tree Planting Day.    2    . At the time, a forestry expert suggested designating (定义) the Qingming Festival, also known as Tomb-Sweeping Day, as the National Tree Planting Day. After the death of Sun Yat-sen on March 12, 1925, the National Tree Planting Day was changed to fall on March 12 to remember Sun’s support for national afforestation (植树造林).

Since the People’s Republic of China was founded in 1949, the Chinese government has continued to use the day to honor Sun’s contribution to the country.    3    

In 2019，a research team of Boston University found that the global green leaf area has increased by five percent since the early 2000s.     4     , they thought it was because of a “warmer, wetter climate and fertilization from the added carbon dioxide in the atmosphere”. But with a two-decade-long data (数据) record from NASA, they see that humans are contributing.    5    .

In 2021，China planted 3.6 million hectares of forest and changed 380,800 hectares of farmland into forest. The country plans to plant 6.4 million hectares of trees and grass this year.

【推荐1】Artificial intelligence (AI) might be able to spot the next virus to jump from animals to humans, Scottish researchers report.

Identifying diseases before they become a threat to humans is challenging, because only a few of the nearly 2 million animal viruses can infect humans. By developing machine learning models, researchers can analyze genetic patterns of viruses that might infect people. “Our findings show that the zoonotic (动物传染人的) potential of viruses can be inferred to a surprisingly large extent from their genome sequence (基因组序列).” the researchers at the University of Glasgow reported. “By highlighting viruses with the greatest potential to become zoonotic, genome-based ranking allows further ecological and virological characterization to be targeted more effectively.”

The researchers said the models are only a first step in identifying animal viruses with the potential to infect humans, however. Viruses flagged by the models will need laboratory test confirmation before researchers pursue funding for further study. Although these models may predict if viruses might infect humans, that’s only one part of the broader risk. Zoonotic risk is also influenced by how destructive a virus is in humans, as well as its ability to transmit between people, and ecological conditions at the time of human exposure.

The findings were published online in the journal PLoS Biology. Co-author Simon Babayan said these findings add important information to that collected from genetic sequencing of viruses using AI techniques. “The more viruses are characterized, the more effective our machine learning models will become at identifying the rare viruses that ought to be closely monitored and prioritized for vaccine development.” Babayan added.

【推荐3】When Shakespeare called sleep “nature’s soft nurse”, he was certainly onto something. Centuries later, researchers have’ found that inadequate sleep in children affects their emotional functioning in ways that may predict longer- term social problems. A new study, conducted by a professor of psychology, Candice Alfano, examined whether changes in children’s facial expressions of emotion after sleep restriction (限制) predict social problems concurrently (同时发生) and/or over time.

“Sleep problems in children are routinely linked with lower social competence and more problems in peer (同龄) relationships, but we really don’t understand what drives these associations,” reports Alfano, assuming that the answers might partly lie in the ways children’s faces express emotions when tired.

To test this theory, Alfano and colleagues examined 37 children between the ages of 7 and 11 during two in-lab emotional assessments: one when children were well-rested and the other after two nights of partial sleep restriction. During these assessments, children viewed positive(think kittens and ice cream) and negative (think getting a shot and fierce dogs) pictures on a computer screen while a camera recorded their facial expressions. Participants’ parents provided reports of their child’s social functioning at that time and approximately two years later.

“As we suspected, children who displayed less positive facial expressions in response to pleasant images when sleep was restricted were reported to have more social problems two years later, even when controlling for earlier social problems.” said Alfano.

Although concurrent relationships between sleep-based changes in facial expressions and social problems were not found, Alfano suggests that this may be due to developmental differences in social behavior and peer relationships.

“For younger children, more clearly-shown behaviors such as sharing and taking turns may be more important for friendships than facial expressions. However, emotional expression becomes more important with age, explains Alfano.

The results indicate poor sleep quality in childhood forecasts later socio-emotional problems and also indicate the importance of studies exploring how sleep affects many aspects of children’s mental health and well-being.