Two recent studies have found that punishment is not the best way to influence behavior.

    One showed that adults are much more cooperative if they work in a system based on rewards. Researchers at Harvard University in the United States and the Stockholm School of Economics in Sweden did the study.

    They had about two hundred college students play a version of the game known as the Prisoner's Dilemma. The game is based on the tension between the interests of an individual and a group. The students played in groups of four. Each player could win points for the group, so they would all gain equally. But each player could also reward or punish each of the other three players. Harvard researcher David Rand says the most successful behavior proved to be cooperation. The groups that rewarded the most earned about twice as much in the game as the groups that rewarded the least. And the more a group punished itself, the lower its earnings. The study appeared last month in the journal Science.

    The other study involved children. It was presented last month in California at a conference on violence and abuse（虐待）. Researchers used intelligence tests given to two groups. More than eight hundred children were aged two to four the first time they were tested. More than seven hundred children were aged five to nine. The two groups were retested four years later, and the study compared the results with the first test. Both groups contained children whose parents used physical punishment and children whose parents did not.

    The study says the IQs of the younger children who were not spanked were five points higher than those who were. In the older group, the difference was almost three points. The more they are spanked, the slower their mental development.

    It was when I was walking to my office, trailed by three young people whose ages ranged from 16 to 25, flowing down the corridor behind me like the tail of a kite, that I thought of it for the first time.

    This could be because I am not actually a mother. Until recently, I was not a "real" stepmother either. But I have been living with the man who is now my husband, Bernardo for 10 years and in those 10 years, not only have his younger daughters spent every other weekend and half of their school holiday with us but also his son has lived with us full-time. In fact, when Bernardo asked me to move in, he asked his son for permission first.

    Being a step mum is hard enough but being a sort-of-step-mother is about the most awkward position a mature woman can find herself in. With my sort-of-steppies, I have occupied a place of influence, power and sometimes extreme anger by turns. I have stepped on a delicate path between being a grown-up friend, a bridge of influence with their father, the woman of the house, and a figure of authority – but not too much.

    Love the kids or hate them, you must always remember that no matter how much you cook, clean, hug, comfort and discipline, you will never actually count.

    To survive, I trained myself to love the stepkids as hard as I could, but not to care. It's a handy piece of good mental health trickery I recommend to anyone in my position. I can help with homework, yes, but not bother about the results of that homework. I can teach them good manners, but not care about the bad habits they learn at home. Semi-detached is the position.

    Just as John Lubbock said, we may sit in a library and yet be in all quarters of the earth. Here are some of the coolest libraries of the world.

    Stuttgart City Library

    Despite a classic white-on-white color, Stuttgart City Library is one of the most visually appealing modern libraries. The amazing modern and simple look is the product of the Korean architect Yi Eun-young. The German library opened in 2011, and cost nearly 80 million euros to construct.

    Kanazawa Umimirai Library

    Architects from the Coelacanth K&H Architects studio designed the Kanazawa Umimirai Library lo create the best reading environment. Healed floors, an outpouring of natural light, and other features were specifically included lo achieve this goal. The wall, which consists of thousands of tiny openings, allows natural lighting into the building, improving the overall feel of the space. This Japanese library was opened in 2011, and reflects the appearance of many modern and simple spaces.

    Library of Congress

    In 1800, Congress set up the Library of Congress in Washington D.C. Fifteen years later, Thomas Jefferson offered his personal library to replace books that were lost when the British set the building on fire in 1814. His books, which took nearly 50 years to collect, varied from texts on science, literature and philosophy, to books in a variety of foreign languages. These days, the Library of Congress offers more than 155 million items and the largest rare book collection in North America.

    State Library of Victoria

    The Slate Library of Victoria, located in Melbourne, Australia, is one of the largest exhibiting libraries in the world. Though it opened in 1856, major repairs took place between 1990 and 2004. The La Trobe Reading Room is one of the library's main attractions due to its visually amazing architecture. The lawn at the library's front attracts hundreds of city folk each day, who gather for lunch or to enjoy the statues there. The library currently contains over two million books, as well as armor (盔甲) of Ned Kelly, a folk hero against the ruling class.

    The Children's Groundwater Festival, first organized by the Groundwater Foundation 19 years ago, is celebrated every year in Nebraska, a state of the central United States in the Great Plains. After organizing the festival for 16 years, the foundation passed the program on to the local community of Grand Island, Nebraska. The festival is an annual event for fourth and fifth graders of Nebraska. It is an interesting and energetic day filled with hands­on education. Water magic, folk singers and musicians, storytellers, and bird shows add to the happy atmosphere during the festival. There are also some educational activities:

    Gooey Garbage: Children build a landfill (废物填埋场) and learn how a properly­built landfill can protect groundwater.

    Water Races: Children learn about water pollution by racing a drop of water through a model.

    Well in a Cup: By building a small aquifer (蓄水层) in a cup, children learn about aquifers and drinking water wells.

    Taster's Choice: Children drink different types of water, from tap water to bottled water. Then they are taught about the treatment process of each type of water.

    There's No New Water: Students are taught to make a special glass container and learn about the water cycle.

    The Children's Groundwater Festival not only has a great influence on Nebraska's people. So far, similar festivals have been held in nearly 40 American states, Mexico City, several provinces in Canada, and New Delhi, India. People everywhere are realizing the importance of educating young people to learn and care about groundwater.

    For more information about this festival, remember to watch our program tomorrow evening. I'll be waiting for you.

    Scientists have found evidence of a link between social and economic status and childhood attention deficit disorder(ADHD)(注意力缺陷多动障碍)in the UK. A team led by the University of Exeter Medical School analysed data from the Millennium Cohort Study, a database of more than 19, 500 UK children born between 2000 and 2002 .The study was published in the Journal of Child Psychology and Psychiatry.

    Findings showed that more children with ADHD came from families below the poverty line than the UK population as a whole, with average family incomes for households whose study child was affected by ADHD at £324 per week, compared to £391 for those whose child was not. The study found the odds (机会)of parents in social housing having a child with ADHD was roughly three times greater than for those who owned their own homes.

    The team also found that the odds of younger mothers having a child with ADHD were significantly higher than for other mothers. Mothers with no qualifications were more than twice as likely to have a child with ADHD than those with degrees, and lone (孤独的)parents were more likely to have a child with ADHD diagnosis than households with two live-in parents.

    Information was gathered from surveys when the cohort children were nine months old, and at the ages of three, five, seven and eleven.

    Dr Ginny, of the University of Exeter Medical School, who led the study, said, "There is a genetic element to ADHD, but this study provides strong evidence that ADHD is also associated with a disadvantaged social and economic background. Some people believe that ADHD in children causes disadvantage to the economic situation of their family, but we found no evidence to support that theory. It's important to discover more about the causes of this disorder so that we can look towards prevention, and so that we can target treatment and support effectively. "

Fourteen-year-old Harini Logan won the Scripps National Spelling Bee last Thursday, defeating 12-year-old Vikram Raju in a tie-breaker. It's the first time the con test has ever been decided by a tie-breaking round of spelling.

A spelling bee is a contest where players take turns spelling words. Players who spell a word wrong are out of the contest. As the con test goes on, the words get more difficult. Normally, the contest ends when there's only one player left who hasn't made a mistake. Though the bee is mainly about spelling, since 2021 it has changed slightly to also focus on the meaning of the words. During parts of the contest, students were asked to choose the correct meaning of a word.

That caused trouble for Harini. She was asked about the meaning of the word "pullulation". She said the word described the nesting of birds. The con test organizers had expected the answer the "swarming of bees". Harini was removed from the contest. But soon she was back in—the judges double checked and learned that Harini's definition was also correct. One by one, the other students spelled a word wrong and got out. Finally, only Harini and Vikram were left.

The Scripps bee has been running for over 90 years. Many times it ended in a tie. As a result, the contest organizers changed the rules. They added a "spell-off" to the contest to make future ties much less likely. In the spell-off, Vikram and Harini each took turns trying to spell the words they were asked, but both made mistakes. At one point, Harini could have won by spelling the word "drimys"（a kind of plant）correctly. But she missed It.

That put the two into a super tie-breaking event, where they were each given 10 second s to correctly spell as many words as they could. In 90 seconds, Vikram had spelled 13 words correctly. Harini had 21 correct spellings, making her the new winner.