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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    The female dog, who Leonard appropriately named Gobi, joined Leonard on the second day of the annual 4 Deserts Race Series and ran side-by-side with him for 77 miles. Leonard noticed Gobi running with 101 runners during the first day, but on the second day, Gobi was on the start line, looking up at him. "This was the first contact I had with her and as I ran off the line I noticed her by my side," he said. "I didn't speak much to her that day, but at the finish line she followed me into the tent and we slept next to each other. That was it then."

    Leonard shared his sleeping space, water and food with his small companion during the race. He even lent her a hand when needed. "I carried her across rivers that she could not cross on her own," he wrote on his Crowdfunder page.

    After the race, it was clear to Leonard that he had developed a special bond with the pup and started researching ways to get Gobi to the UK. He learned that it would take four months for Gobi to be medically checked and cleared for entry, all of which will cost $6,560 USD, an amount that has been surpassed(超过) due to a successful Crowdfunder campaign that raised $13,330 USD.

    John, a very thin boy, loved football with all his heart when he was very young. Practice after practice, he eagerly gave everything he had. But being half the size of the other boys, he could only sit on the bench and hardly ever played in games. Even though the son was always on the bench, his father was always standing with cheers and encouraging him.

    When John went to college, he decided to try out for the football team as a “walk-on”. Everyone was sure he could never make the cut, but he did. The coach thought he could provide the other members with the spirit they needed.

    The news that he had survived the cut excited him so much that he rushed to the nearest phone and called his father. His father shared his excitement and was sent season tickets for all the college games.

    It was the end of this last football season. One day John received a telegram and asked one week off. Nobody knew what happened except the coach. The coach said, “Don't plan to come back to the game on Saturday.”

    Saturday arrived, and the game was not going well：When the team was ten points behind, John came back. “Coach, please let me play. I've just got to play today,” said John. The coach pretended not to hear him. But John persisted, and finally feeling sorry for the kid, the coach gave in.

    Before long everyone could not believe their eyes. John was doing everything to fight. The opposing team could not stop him. He ran, he passed and blocked like a star. And at last his team won the game.

    After the game, John looked at the coach, with tears in his eyes, and said, “Well, you knew my dad died, but did you know that my dad was blind?'' John swallowed hard and forced a smile, “Dad came to all my games, but today was the first time he could see me play, and I wanted to show him that I could do it.”

    No one knew Prince Edward Street as well as Pierre Dupin. He had delivered milk to the families on the street for thirty years. For the past fifteen years a large white horse named Joseph pulled his milk wagon. Joseph was a gentle horse with beautiful spirit shining out of its eyes, so Pierre named him after Saint Joseph.

    Every morning at five, Pierre arrived at the milk company's stables to find Joseph waiting for him, Pierre would call, "Good morning, my old friend." as he climbed into his seat, while Joseph turned his head toward the driver. And the two would go proudly down the street. Without any order from Pierre, the wagon would roll down three streets. Then it turned right for two streets, before turning left to Saint Catherine Street. The horse finally stopped at the first house on Prince Edward Street. There, Joseph would wait perhaps thirty seconds for Pierre to get down off his seat and put a bottle of milk at the front door.

    Pierre knew every one of the forty families that got milk. The cooks knew that Pierre could not read or write; so, instead of leaving orders in an empty milk bottle, they simply sang out if they needed an extra bottle.

    Pierre also had a wonderful memory. When he arrived at the stable he always remembered to tell Jacques, the foreman(领班) of the stables, "The Pacquins took an extra bottle this morning; the Lemoines bought a pint of cream …" Most of the drivers had to make out the weekly bills and collect the money. But Jacques, liking Pierre, never asked him to do this.

    One day the president of the milk company came to inspect the early morning milk deliveries. Jacques pointed to Pierre and said："See how the horse listens and how he turns his head toward Pierre? See the look in that horse's eyes? You know, I think those two share a secret. I have often felt it. He is getting old. Maybe he ought to be given a rest, and a small pension."

    "But of course," the president laughed. "He has been on this job now for thirty years. All who know him love him. Tell him it is time he rested. He will get his pay every week as before."

    But Pierre refused to leave his job. He said his life would be nothing if he could not drive Joseph every day. "We are two old men," he said to Jacques. "Let us wear out together. When Joseph is ready to leave, then I too will do so."

    Then one cold morning Jacques had terrible news for Pierre. Jacques said,"Pierre, your horse, Joseph, didn't wake up. He was very old, Pierre." Jacques said softly. "He is over in his stall, looking very peaceful. Go over and see him." Pierre took one step forward, then turned. "No … no … I cannot see Joseph again. You … you don't understand, Jacques."

    For years Pierre had worn a large heavy cap that came down low over his eyes. It kept out the bitter cold wind. Now, Jacques looked into Pierre's eyes and he saw something that shocked him. He saw a dead, lifeless look in them.

    "Take the day off, Pierre," Jacques said. Pierre walked to the corner and stepped into the street. There was a warning shout from the driver of a big truck … there was the screech(尖锐的刹车声) of rubber tires as the truck tried to stop. But Pierre heard nothing.

    Five minutes later a doctor said, "He's dead … killed instantly."

"I couldn't help it," the truck driver said. "He walked in front of my truck. He never saw it, I guess. Why, he walked as though he were blind."

    The doctor bent down. "Blind？Of course, this man has been blind for five years."  He turned to Jacques, "Didn't you know he was blind？"

    "No …no …" Jacques said softly. "None of us knew. Only one … only one knew－a friend of his, named Joseph … It was a secret, I think, just between those two."

    Fashions have a lot of rules. Most of them, however, are just wrong. But there's one rule that goes beyond tradition and into the field of scientific study of the brain: Black garments are slimming. It all comes down to how your visual system processes the light. The below holes in each square are the same in size, yet the white hole looks bigger than the black hole.

    In the 1500s, Galileo Galilei noticed that some of the planets looked larger when viewed with the naked eye (肉眼) than they did when viewed through a telescope, making the white light of Venus (金星) appear eight to ten times larger than Jupiter (木星) in the night sky. He knew something strange must be going on with his vision to cause this illusion, but he wasn't sure what it was. Luckily, scientists never stopped wondering, and in 2014, they figured it out.

    Our visual system operates via two main channels: "on" neurons (神经元) that are sensitive to light things and "off" neurons that are sensitive to dark things. When it came to the dark "off" neurons, the researchers found that they responded predictably to dark shapes on a light background — the greater the contrast between the two, the more active these neurons were. But the light "on" neurons behaved unpredictably. Even with the same amount of contrast, light objects on a dark background caused a greater response in these neurons.

    This makes some sense, evolutionarily speaking. In the dark of night, you'd want to be able to take in every bit of light you can get, so a visual system that enlarges light objects on a dark background could be very useful. However, it's not that hard to see dark objects in the light of day. It has some effects in the colors of your clothes and in the appearance of the planets—the brighter appearance of Venus in the night sky makes it look bigger than the darker Jupiter.

    In October 2013, Davion Only made an appeal on the Internet. He had learned that his biological mother had died not long before. "My name is Davion and I've been in foster care (寄养照管) since I was born," he said, "but I'm not giving up hope. "

    The heartbreaking appeal spread quickly, and Only's foster agency received calls from more than 10,000 people. Only ended up travelling to Ohio to live with a family. But after Only got into a physical fight with one of his elder would-be brothers, the family changed their minds.

     Back in Florida, Only passed through four different temporary homes over the following year, until he called Connie Going, his adoption case worker, to make a special request. Only had known Going for nearly ten years, and had asked every year if she would adopt him, but she always hesitated. "I always believed there was a better family than us out there," Going said in an interview. But last July, when Only called and asked again if she might adopt him, Going said something felt different. "When he asked me, my heart felt this ache and I just knew he was my son," she said.

     So Going, 52, invited Only to start spending time with the rest of her family-her two daughters, Sydney, 21, and Carly 17, and a son Taylor, 14, who she also adopted out of foster care. Eventually, after seeing how well the arrangement was working, Going, who had rented a bigger home, started adopting Only. Only moved in with her family last December. He officially joined Going's family on April 22, 2015 when the adoption papers went through.

    "Today, I feel blessed and honored to have been chosen to be the parent of all my children," Going said.