When Luke went to university he thought he would be on a new journey in life and getting his own place. In the UK, it's common to fly the nest at a fairly young age. Many choose a flat-share; others make plans to get on the property ladder.

    But the current economic situation forced Luke back to his mum's house at the age of 27. And he's not alone: a quarter of young adults in the UK now live with their parents. The Office for National Statistics said more than 3.3 million adults between the ages of 20 and 34 were living with their parents in 2013.

    Lack of jobs and the high cost of renting accommodation made Luke change his plans. He's upset. "There's something very difficult about being an adult living in an environment where you're still a child," he says. "It limits me socially; sometimes I feel it limits me professionally."

    Indeed, many young people have no choice but to stay at "the hotel of Mum and Dad".

    Krissy had to return home after a year away and now lives in rather terrible conditions, sharing the family's three-bedroom house with her sisters. She says they end up getting on each other's nerves when it's time to use the bathroom in the morning.

    Of course, living with your parents is not unusual in some countries. Economic conditions, culture, or family traditions mean many young people stay at home until they get married. Even then, it can be too expensive to rent or buy a house and the married couples continue to live at one of their parents' homes.

    But some parents seem to enjoy having their kids back at home. Janice's daughters are part of what's being called "the boomerang generation". She says, "I get to share their lives with them, and I've got to know them all as adults. We have the sort of conversations that good friends do."

    So for some it's a win-win situation — spending time with your families, and saving money.

    Can small, organic agriculture really feed the world? Won't we need science to produce enough food as the world population is growing to 9 billion by 2050? The answer to both questions is YES—but that science may look different than you think.

    We've been told that the only way we'll be able to feed the growing population is through the science of GM(转基因) crops and chemicals. But the latest scientific studies are saying just the opposite. In study after study, the message about agriculture is: To feed the world, we need to support sustainable (可持续的) agriculture on different, local, family farms that work with nature.

    In 2008, an international study found that sustainable agriculture, not GM crops, shows more hope of ending hunger. The International Assessment of Agricultural Knowledge, Science, and Technology for Development (known as the IAASTD), calls for a change of the world's food and farming systems.

    The Assessment said that industrial agriculture has greatly destroyed the world's soils and other natural resources, and now is doing harm to water, energy, and weather safety. The report warns that expensive, short-term ways—including GM crops—are not likely to cut down long-term hunger, and could even make environmental and social problems worse in many places.

    A recent report by the UN Environment Program shows that food problems will become more serious because of environmental problems and strongly supports sustainable agriculture on small family farms. It also showed that a worldwide change to organics could actually increase the world's food production by as much as 50%—enough to feed a population of 9 billion people with the land we have now. GM crops, once popular, are now being questioned worldwide.

    I was raised in a house where my sisters and I weren't trusted by our mother to manage our own appearance. As a result, there were rules, and trends were largely ignored. A few years ago, I was home for a visit when my mom, now in her early 70s, called me into her bedroom. We were about ready to leave for dinner. “I don't know what to wear” she complained “You girls always look so good. ”

    I paused in the doorway and looked at her, wondering if I'd misheard. “What do you mean?” I asked her. “You know what to wear" No. ”she answered. “I don't. Can you pick something?” I was so surprised.

    This was the same woman who, in 1989, told my younger sister she wasn't allowed to leave the house wearing a pair of ripped(有破洞的)jeans；the same woman who, in high school, called me while l was out at a party to ask if my hair was up. “You look better with it down, ”she told me, before I could answer I realized, suddenly, that my mother—always so strong—not only wanted my opinion, but needed it. I pulled a pair of blue jeans from the closet and a light blue sweater from her drawer “Wear this with your black shoes, ”I told her. She did My mother certainly doesn't need anyone to take care of her. In fact, she still cares for my grandmother who lives with her. But with that one question, my mother and I started the role reversal(转变)that happens with all parents and all children, from caregiver to receiver.

    Now, if I'm visiting or we're together, it's rare for her to wear anything without checking with me first. But every so often, it seems like she asks me just to be able to disagree with my answer and pick out something on her own. And when she does, I just tell her what I think of the way she looks. Sometimes it's “great”. And sometimes it's "awful."

    Why does time seem to fly by faster as we get old? You've got your aging brain to blame. This is likely due largely to the physical changes of our nerves and neurons (神经元). New research suggests 'rapid fire' abilities of the young brain allow us to process more information during youth, causing the days to seem longer earlier in life. However, as we get old, researchers say the older brain takes more time to process information.

    The new finding put forward by a Duke University researcher was published in a paper in the journal European Review this week According to Adrian Bejan, the J. A Jones Professor of Mechanical Engineering at Duke, the physical changes of our nerves and neurons play, a major role in our perception (知觉) of time as we get old. Over the years these structures become more complex and eventually begin to degrade.

    "Little babies, for example, move their eyes much more often than adults because they're processing images at a faster rate," Beian says, For older people, this means fewer images are being processed in the same amount of time, causing experiences to seem as though they're happening more quickly.

    Steven Stein likes to follow garbage trucks. His strange habit makes sense when you consider that he's an environmental scientist who studies how to reduce litter, including things that fall off garbage trucks as they drive down the road. What is even more interesting is that one of Stein's jobs is defending an industry behind the plastic shopping bags.

    Americans use more than 100 billion thin film plastic bags every year. So many end up in tree branches or along highways that a growing number of cities do not allow them at checkouts(收银台) . The bags are prohibited in some 90 cities in California, including Los Angeles. Eyeing these headwinds, plastic-bag makers are hiring scientists like Stein to make the case that their products are not as bad for the planet as most people assume.

    Among the bag makers' argument: many cities with bans still allow shoppers to purchase paper bags, which are easily recycled but require more energy to produce and transport. And while plastic bags may be ugly to look at, they represent a small percentage of all garbage on the ground today

    The industry has also taken aim at the product that has appeared as its replacement: reusable shopping bags. The stronger a reusable bag is, the longer its life and the more plastic-bag use it cancels out. However, longer-lasting reusable bags often require more energy to make. One study found that a cotton bag must be used at least 131 times to be better for the planet than plastic.

    Environmentalists don't dispute(质疑) these points. They hope paper bags will be banned someday too and want shoppers to use the same reusable bags for years.

    Throughout our daily lives, we have known plenty of people and will know more. But how can we tell if someone is trustworthy? In a paper published recently in the Journal of Personality and Social Psychology, researcher gave us the answer.

    The researchers asked 401 adults from the United States to fill out a questionnaire measuring their guilt-proneness (内疚倾向) in different situations as well as several other qualities, and then play a short online game. In this game, Player 1 is given $1, which they can choose to give to Player2. Any money given to Player 2 is then automatically increased to $2.50. Player 2 can then decide whether to keep all of the money or behave in a trustworthy way by returning a portion of the money to Player 1. The researchers found more guilt-prone people were more likely to share the money with Player 1. Actually, in follow-up studies, guilt-proneness predicted trustworthiness better than other personality qualities the researchers measured.

    Why might guilt lead to trustworthy behavior? The researchers found people who were guilt-prone also reported feeling an obligation to act in ethical (合乎道德的) and responsible ways while interacting (互动) with their partners in the game. People who are guilt-prone tend to avoid engaging in behavior that might harm or disappoint others. If they do something bad, guilt encourages them to try to make things right again.

    Then, how can we use this research to ascertain whether someone is trustworthy? "One way to do this might be observe how they respond to experience regret," lead author Emma Levine, assistant professor at the University of Chicago Levine, explains. Another way is to ask them to describe a difficult dilemma they faced in the past, suggests co-author Taya Cohen, associate professor at Carnegie Mellon University. This is particularly effective, Cohen and her colleagues have found, because it allows us to see if they're concerned about the effects their actions have on others.