【推荐1】Pigeons (鸽子) may be considered mice of the sky, but some scientists have found greater value in these urban birds: the blueprint for a new generation of flying machines.

Birds can transform the shape of their wings by fanning out their feathers or moving them closer together. Those adjustments allow birds to cut through the sky more flexibly than rigid drones (无人机). Now, using new insights into exactly how pigeons ‘joints control the spread of their wing feathers, researchers have built a robotic pigeon. This research paves the way for creating more light aircraft, says Dario Floreano, a roboticist in Switzerland not involved in the work.

“What’s really cool about this robot is that you can make adjustments in a robotic wing that you could never do when studying flight in a bird”, says David Lentink, an engineer and biologist at Stanford University. A controllable robotic pigeon solves that problem. In flight tests, Lentink’s team observed that bending only the fingers of one wing eased the robot into a banked turn-offering the first evidence that birds may sometimes use just their fingers to direct in flight. In a second study, Lentink’s group used their robotic wing design to confirm another insight into bird flight: how gaps are prevented from forming between feathers on extended wings.

This is the best set of robotic wings yet for testing how birds adjust their flight feathers to move through the air, says Tyson Hedrick, a biomechanist. But “there’s plenty of room for improvement.” For instance, a future flying robot could include a shoulder joint to investigate how waving a bird’s wings up and down influences flight, he says.

【推荐3】Music is an important part of life today. It is a source of entertainment, and it is a way to express emotions. But music is not only all this, it is also something that can be used to create a strong focus while people are working and is generally beneficial to the human brain and specifically the adolescent brain.

Music can reduce anxiety and depression, as well as improving mood and memory. Adolescents represent a stage in development when stress levels are unsteady. An analysis shows that listening to music lowers the stress hormone in the brain. Ashford University also states that music has also proven to be effective across a variety of treatment ways for conditions ranging from premature birth to depression to Parkinson’s disease.

Music is also a way to stimulate (刺激) the brain and help increase productivity. In Elena Mannes’ study “The Power of Music”through National Public Radio(NPR), she declares the fact that music stimulates more parts of the brain than any other human function. Tests have also shown that listening to background music can increase productivity, in majors we listen to music as we do our work, "says visual artist, Tow Engel, “It is super helpful because it allows us all to do our own thing to create more art.”

Research done by Dr. Jonathan Burdette, a professor at the Wake Forest Baptist Medical Cater, further proves the benefit of music on the brain. Dr. Burdette conducted a study where he and his fellow investigators used a technique called functional magnetic resonance imaging(FMRI), to find changes in blood flow in the brain. To summarize, Dr. Burdette’s research shows that listening to music that you like will improve brain connectivity, especially when doing independent work that requires a lot of internal thought and reflection. As adolescents spend a lot of time working on computers or even just doing work on paper done, music can help teens concentrate on their thinking

【推荐3】The International Union for Conservation of Nature(IUCN) added the Chinese paddlefish (白鲟) to its list of threatened species in July, 2022. People will never see a living Chinese paddlefish again as it has been declared extinct. For many people in China, this might be the first time they had heard the name of the fish that was once a denizen(栖息者) of the Yangtze River Basin.

The fish is thought to have been around since about 200 million years ago. It was among the world’s biggest freshwater species and could grow up to 7.5 meters in length. The last time the fish was spotted was in 2003 in the upper reaches of the Yangtze River in Yibin, Sichuan Province. It was an injured female sturgeon(鲟鱼). After local people treated its wounds, it was released into the river.

According to the IUCN, the global sturgeon reassessment found that 100 per cent of the remaining 26 sturgeon species in the world are now at risk of extinction, up from 85 per cent in 2009. Their decline over the past three generations is steeper than previously thought.

“The extinction of the Chinese paddlefish should be a warning to everyone,” said Zhou Fei, China’s chief program officer at the World Wide Fund for Nature. “It has provided an opportunity for conservation experts to raise public awareness about the urgency of protecting freshwater species in the Yangtze River Basin and educate the public on the need for more efforts to save other species living in the region from extinction,” he added.

To prevent further loss of freshwater species in China, people must act urgently. There is no time to waste. Also, long-term threats to their life and habitats must be eliminated by taking systematic protection measures. The protection of biodiversity will delay the extinction of some species. It’s not something that can be achieved by certain departments. Instead, it requires joint efforts from all sectors of society.

【推荐1】Like many other people, I love my smart phone, which keeps me connected with the larger world that can go anywhere with me. I also love my laptop，because it holds all of my writing and thoughts. In spite of this love of technology, I know that there are times when I need to move away from these devices and truly communicate with others.

On occasion, I teach a course called History Matters for a group of higher education managers. My goals for the class include a full discussion of historical themes and ideas. Because I want students to thoroughly study the materials and exchange their ideas with each other in the classroom, I have a rule—no laptop, ipads, phones, etc. When students were told my rule in advance of the class, some of them were not happy.

Most students assume that my reasons for this rule include unpleasant experiences in the past with students misusing technology. There’s a bit of truth to that. Some students assume that I am anti-technology. There’s no truth in that at all. I love technology and try to keep up with it, so I can relate to my students.

The real reason why I ask students to leave technology at the door is that I think there are very few places in which we can have deep conversions and truly engage complex ideas. Interruptions by technology often break concentration and allow for too much dependence on outside information for ideas. I want students to dig deep within themselves for inspiration and ideas. I want them to push each other to think differently and make connections between the course materials and the class discussion.

I’ve been teaching my history class in this way for many years and the evaluations reflect student satisfaction with the environment that I create. Students realize that with deep conversation and challenge, they learn at a level that helps them keep the course materials beyond the classroom.’

I’m not saying that I won’t ever change my mind about technology use in my history class, but until I hear a really good reason for the change, I’m sticking to my plan. A few hours of technology-free dialogue is just too sweet to give up.

【推荐2】Ecology is a complicated thing. c Given the facts that elephant damage often kills trees and bush fires often kill trees, a combination of the two will make things worse. However, as research shows just published in Biotropica, by Benjamin Wigley of Nelson Mandela University, if a tree has already been damaged, fire can actually help to make things better.

Since 1954，the Kruger National Park has been the site of experiments. Dr Wigley carried out these experiments by looking at trees in three different zones. In one of these zones, the vegetation (植被) was burned every year. In the second it was burned every other year. The third zone, by contrast, was actively protected from fire. To keep things consistent, he only looked at the fate of a single tree species, the marula (玛鲁拉树), whose bark is often eaten by elephants. In July 2016, he and his colleagues identified 20 marulas in every zone and used a hammer and a knife to remove a 5 cm circular section of bark from each of them.

To their surprise, damaged trees in the annual burnt zone regrew 98% of their lost bark during the two years of the study. Those living in the second burnt zone regrew 92% of it. But those in the zone where fires were banned regrew only 72%.

The researchers also found something else around the trees' wounds: ants. Ten of the 20 trees in the fire-banned zone developed ant colonies in their wounds. The ants were known to damage tissue healing. By contrast, only five trees in the second zone and three in the annual zone developed ants' nests in their wounds.

It looks, therefore, as if bush fires are burning trees'。wounds to kill the ants. Though such fires are surely harmful to healthy trees, it seems, in an example of two negatives making a positive, as if they are actually helpful to sick ones.