The more hours young children spend in child care, the more likely they are to turn out aggressive and disobedient by the time they are in kindergarten, according to the largest study of child care and development ever conducted. Researchers said this correlation(相关性) held true regardless of whether the children came from rich or poor homes, were looked after by a relative or at a center, and whether they were girls or boys.

    What is uncertain, however, is whether the child care actually causes the problem or whether children likely to turn out aggressive happen to be those who spend more hours in child care. It also remains unclear whether reducing the amount of time in child care will reduce the risk that a child will turn into a mean person. What's more, quality child care is associated with increased skills in intellectual ability such as language and memory, leading some academics to suggest that child care turns out children who are "smart and naughty".

    The government-sponsored research, which has tracked more than 1,300 children at 10 sites across the country since 1991, is bound to cause the debate over child care again: How should people balance work and family? And how should parents, especially mothers, resolve the demands that are placed on them to be both breadwinners and supermoms?

    That debate was already on display at a new briefing yesterday, where researchers themselves had different opinions about the data and its implications（含义）. "There is a constant relationship between time in care and problem behavior, especially those involving aggression and behavior," said Jay Belsky of Birkbeck College in London, one of the lead investigators of the study who has previously annoyed women's groups because of his criticisms of child care. "On behalf of fathers or mothers?" interrupted Sarah Friedman, a developmental psychologist at the National Institute of Child Health and Human Development (NICHD) and one of the other lead scientists on the study. "On behalf of parents and families," responded Belsky.

    "NICHD is not willing to get into policy recommendations," said Friedman, contradicting her colleague. "There are other possibilities that can be entertained. Yes it is a quick solution—more hours in child care is associated with more problems. The easy solution is to cut the number of hours but that may have implications for the family that may not be beneficial for the development of the children in terms of economics." In an interview after the briefing, Friedman said that asking parents to work fewer hours and spend more time with their children usually meant a loss of family income, which adversely（不利地）affects children.

    Scientists said that the study was highly reliable. But the researchers said they had no whether the behavioral difficulties persisted as the children moved to higher grades.

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    What's more exciting than having a fresh hot pizza delivered to your door? How about having it brought to you by a robot? Thanks to Domino's Robotic Unit or DRU, that just became a reality! On March 8, the three-foot tall robot delivered its first pizza to some lucky residents in Brisbane, Australia.

    The fully autonomous DRU is the result of a cooperation between Domino's Pizza Australia and Marathon Robotics.The 450-pound machine that travels at a maximum speed of 12.4 miles an hour can traverse a distance of up to 12 miles and back, before requiring a battery recharge. LIDAR, a laser-based sensor technology similar to the one used in self-driving cars, enables DRU to detect and avoid obstacles, while traditional sensors, much like those used in vacuum robots ensure its path is safe as it heads to its destination.   

    The robot can fit up to ten pizzas and even has a separate cold area to accommodate drink orders.To access their fond, customers have to enter the unique code provided by the company.This is not only ensures that they pick up the right pizza, but also prevents the pies from getting stolen.

    Scientists expert additional DRU's to be ready for service in their various Queensland locations within the next six months. But don't expect these super cute robots to replace humans anytime soon. According to Domino's the DRU still needs extensive testing, which the company believes could take up to two years.

    And then there is also the issue of regulations.The public use of autonomous vehicles is still banned in most countries.But Don Meij, the CEO and Managing Director of Domino's Pizza Australia New Zealand Ltd, is not worried.He is “confident that one day DRU will become an   integral part of the Domino's family.”

    One of America's best-known artist colonies, the MacDowell Colony, will turn 110 next year. It is a place where artists of all types can sweep away distractions (令人分心的事物) and just create.

    MacDowell's operations are funded by foundations, corporations and individuals. Writers, composers, photographers, filmmakers and sculptors — both famous and unknown —compete for the 32 free studios at the place. Once accepted, an artist can stay for as little as a couple of weeks, or as long as a couple of months.

    When they arrive, artists find a kind of isolation (隔绝) hard to find in our world. There's no phone. No fax. No friends. No family. It's just a cabin in the snowy woods.

    Writer Emily Raboteau lives in New York City. She came to MacDowell to work on a novel. She received a desk, chairs, pencil and paper — and ice grippers. The walk from one isolated, one-room studio to another is icy, so colony residents (居住的人) fasten the ice grippers to the bottom of their shoes.

    Another colony resident, Belfast composer Elaine Agnew, plays a piece called “To a Wild Rose,” written by Edward MacDowell. She says it's so famous that every pianist in the world has played the tune. A hundred years ago, Macdowell owned the land where the colony now sits. He liked its isolation and his ability to get work done there. After his death, his wife, Marion, encouraged other artists to come.

    And for the last century, artists have accepted the invitation, coming to step outside of their daily lives for a short time. Privacy is respected, but cooperation and discussion is common.

    Screenwriter Kit Carson — who wrote Texas Chainsaw Massacre 2 and the film adaptation of Sam Shepherd's play Paris, Texas — has visited MacDowell twice. He says that the interdisciplinary (学科间的) discussion there is valuable.

    “You sit around at dinner, talking, and then somebody runs off and brings you back some stuff and shows it to you,” he says. “That, I didn't realize, was part of the magic here, because people are really open to showing their opinions here.”

    In a paper published in the journey Science Advance, researchers describe how Matabele ants, a species of large ant known for attacking termite colonies (白蚁群落), will, after the battle, pick up injured fellow soldiers and carry them back to the nest where they can recover.

    The paper is the latest in a growing body of research that this form of helping behavior, previously observed in some mammals and birds, may not require complex emotion, and may, therefore, be far more widespread in nature than previously thought.

    “Here we have an example of an individual saving another individual,” says lead researcher Erik Frank who conducted the research. “We can be quite certain that the ants don't know why they are doing what they are doing.”

    It's a behavior that pays off for the colony. Our classic conception of worker ants is that they are essentially abandoned, but Mr. Frank and his colleagues calculated that the practice of rescuing nest mates results in a colony size that is a 28.7 percent larger than it would be had the ants left their fellow soldiers for dead.

    “These injured ants are able to recover from their injuries, ” says Frank. “They are essential for the safety and the betterment of the colony. ”

    When a Matabele ant is injured, as often happens during battles with termites, its body will give off two smelly chemicals that tell other ants to carry it back to the nest. Indeed, the researchers found that using these chemicals to seek help from uninjured ants will effectively activate the rescue behavior, supporting their theory that the ants were acting on pure instinct(本能), not more complex emotions.

    “The more we study rescue behavior in ants and other animals, the more we are going to realize that it's not just limited to the species we've observed so far, ” says Karen Hollis, a professor at Mount Holyoke College, mentioning studies that found that dolphins help other injured dolphins to the surface for air, capuchin monkeys defend each other during intergroup battles, and rats free other rats that are trapped.

Not many years ago, a rich and kind old man named Johnson lived alone in a village in the south of England. He had made a lot of money by selling and buying goods. When he was seventy-five, he gave f 12,000 to the village to buy land and equipment for a children's playground.

As a result of his kindness, many people came to visit him. Among them was a newspaper man. During their talk, Johnson said that he was seventy-five and expected to live to be a hundred. The newspaperman asked him how he managed to be healthy at seventy- five. Johnson had a sense of humor. He liked wine and drank some each day. "I have an injection(注射)in my neck each evening." he told the newspaperman, thinking of his evening glass of wine.

The newspaperman did not understand what Johnson meant. In his newspaper he reported that Johnson was seventy- five and had a daily injection in his neck. Within a week Johnson received thousands of letters from all over Britain, asking him for the secret of his daily injection.

In May 2019, a friend who had previously been involved in the Restless Development Sierra Leone Business Brains project encouraged me to apply for the "Saving Lives II" project. Seeing this as an opportunity to move closer to my ambition of working in the medical field in the near future, I eagerly seized the chance. Fortunately, my performance during the interview led to me being awarded the role. 

Following the basic training, I was sent to volunteer in Kurubonla, a remote community located in the northern region of Sierra Leone. This assignment presented challenges such as limited road access and communication networks. At first, I felt concerned about being sent there, but with a determined mindset, I set out on the journey, driven by a passion to contribute to my country's development and to push my personal boundaries. 

As I got to know the community, I quickly realized that the challenges extended beyond language barriers and cultural differences; there was also a sense of isolation from my peers. However, I refused to allow these challenges to stop me. I threw myself in my duties, working together with local leaders and community members to identify the most pressing needs. Together, we carried out the projects aimed at improving healthcare, education, and infrastructure (基础设施). Additionally, I organized workshops and training courses to share my knowledge and skills with the locals. 

Over time, I witnessed the positive impact of our collective efforts. Healthcare facilities improved, the number of students in schools increased, and the overall quality of life in the community showed signs of improvement. These achievements were not solely mine; they were a testament to the cooperative spirit and commitment of the entire community.