Artificial intelligence helps teachers identify which of their students have learning difficulties, according to a new study.

Teachers make more accurate assessments of learning difficulties among their students if they are given Al-generated feedback(反馈) rather than an "expert solution" written by a qualified professional. Researchers believe that because the AI analyzed the teacher's own work, it's easier for the teacher to understand than a "model answer" prepared beforehand.

"Teachers play a critical role in recognizing the signs of disorders and learning difficulties in pupils and referring them to specialists," said Riikka Hofmann. "Unfortunately, many of them feel that they have not had sufficient opportunity to practice these skills. AI could provide an extra level of individualized feedback to help them develop these essential competences. "

Trainee teachers were asked to assess fictionalized students for potential learning difficulties, based on evidence including examples of their work, school behavior records and written texts of conversations with parents. Half of the trainees received the "expert solution", typical of the material given to trainee teachers, while the other half received AI-generated feedback on their approach, highlighting where they could improve. The trainees then completed similar follow-up assessments, and were graded both on the accuracy of their diagnoses(诊断) and on how well they had used the evidence. Trainees who received the AI feedback scored significantly higher than those who worked with the pre-written expert solutions.

While the researchers said this does not mean AI is preferable to one-to-one feedback from a skilled expert, this is not always available for trainee teachers. "We are not arguing that AI should replace teacher-educators: new teachers still need expert guidance on how to recognize learning difficulties in the first place," said Dr Michael Sailer. "It does seem, however, that Al-generated feedback helped these trainees to focus on what they really needed to learn. When personal feedback is not readily available, it could be an effective substitute(代替物). "

City parks have long been a place for urban residents to get a small amount of green. As cities increasingly feel the impacts of rising seas and temperatures, people are rethinking the roles of urban parks.

All of the dark-gray asphalt (沥青) in cities collect heat. Dallas is one of the country's fastest-warming cities thanks in part to its extensive impervious (不透水的) surfaces, but with a new $312 million bond package, the city is hoping to change that. Using satellite data, the city is able to see what neighborhoods most need the cooling effect of green spaces.

Cities are increasingly flooding and city planners think parks can help with this issue too. A report published in February by The Nature Conservancy looked at the best ways to deal with flooding in Houston, a city with many neighborhoods built on floodplains and regularly flooded by rising waters. Offering affected homeowners buyouts and transforming homes into green spaces would save more money than installing infrastructure (基础设施) like pipes, they found.

Brendan Shane, a climate program director, says parks can create opportunities for people to exercise and play, in addition to cooling neighborhoods and absorbing floodwater. "The stronger the bonds are from neighbor to neighbor, the better they are able to react to a shock," he says.

"Not a single solution by itself will avoid the climate crisis. We see parks as an important part of it, but there isn't a silver bullet," says Diane Regas, CEO of The Trust for Public Land. "Parks are an example of what we in the environmental community need to do to reach solutions that address climate change at the same time and make people's lives better."

The concentric circles（同心圆状斑点）, also known as eyespots on butterfly, not only look like real eyes but may also appear to glare directly at predators（捕食者）from many directions, scientists have found. This visual illusion, called the "Mona Lisa effect", could scare would-be attackers and buy the insects enough time to escape.

Scientists suspect that eyespots, with dark "pupils（瞳孔）" in the center look like real eyes to predators. Hannah Rowland, an ecologist at the Max Planck Institute wanted to see if the direction of this fake gaze contributed to the effect.

First, Rowland and her co-author trained chicks to attack a worm hidden behind a paper printout of two eyespots at the end of a path. When the eyespots' pupils were specifically pointed in the chicks' direction, the birds repeatedly ran toward the paper and then backed away, and they waited a few minutes before attacking. But when the pupils instead appeared to look away from the direction of the chicks' approach, the birds attacked in seconds. Centrally located pupils, though not as effective as ones that stared directly at the chicks, resulted in longer delays than pupils that looked the other way.

"This suggests that they really are paying attention to the direction of the pupils in the eyespots and are perceiving them as eyelike stimulation. The concentric eyespots found most often in the insect world may seem to the chicks like a pair of eyes that follow them regardless of approach angle," says Rowland.

National University of Singapore evolutionary biologist Antonia Monteiro, who was not involved in the research, says the study is a "cool" demonstration of an evolutionary theory for eyespots. "These butterflies can be encountered from all angles, so having the pupil centrally located ends up being pretty good," Monteiro says. Still, she says, the eyespots used in the study were several millimeters larger than even the largest commonly found in nature, raising the possibility that the chicks may have been extra frightened by the size of the paper eyes.