What will power your house in the future? Nuclear, wind, or solar power? According to scientists at the Massachusetts Institute of Technology (MIT) in the US, it might be leaves — but artificial (人造的) ones.

    Natural leaves are able to change sunlight and water into energy. It is known as photosynthesis (光合作用). Now researchers have found a way to imitate this seemingly simple process.

The artificial leaf developed by Daniel Nocera and his colleagues at MIT can be seen as a special silicon chip with catalysts (催化剂). Similar to natural leaves, it can split water into hydrogen and oxygen when put into a bucket of water. The hydrogen and oxygen gases are then stored in a fuel cell, which uses those two materials to produce electricity, located either on top of a house or beside the house.

Though the leaf is only about the shape of a poker card, scientists claimed that it is promising to be an inexpensive source of electricity in developing countries. “One can imagine villages in India and Africa not long from now purchasing an affordable basic power system based on this technology,” said Nocera at a conference of the American Chemical Society.

The artificial leaf is not a new idea. The first artificial leaf was invented in 1997 but was too expensive and unstable for practical use. The new leaf, by contrast, is made of cheap materials, easy to use and highly stable. In laboratory studies, Nocera showed that an artificial leaf prototype (原型) could operate continuously for at least 45 hours without a drop in activity.

The wonderful improvements come from Nocera's recent discovery of several powerful, new and inexpensive catalysts. These catalysts make the energy transformation inside the leaf more efficient with water and sunlight. Right now, the new leaf is about 10 times more efficient at carrying out photosynthesis than a natural one. Besides, the device can run in whatever water is available; that is, it doesn't need pure water. This is important for some countries that don't have access to pure water.

With the goal to “make each home its own power station” and “give energy to the poor”, scientists believe that the new technology could be widely used in developing countries, especially in India and rural China.

    How fit are your teeth? Are you lazy about brushing them? Never fear: An inventor is on the case. An electric toothbrush senses how long and how well you brush, and it lets you track your performance on your phone.

    The Kolibree toothbrush was exhibited at the International Consumer Electronics Show in Las Vegas this week. It senses how it is moved and can send the information to an Android phone or iPhone via a Bluetooth wireless connection.

    The toothbrush will be able to teach you to brush right (don't forget the insides of the teeth!) and make sure you're brushing long enough. “It's kind of like having a doctor actually watch your brushing on a day-to-day basis,” says Thomas Serval, the French inventor.

    The toothbrush will also be able to talk to other applications(应用) on your phone, so developers could, for example, create a game controlled by your toothbrush. You could score points for beating monsters(怪物) among your teeth. “We try to make it smart but also fun,” Serval says.

    Serval says he was inspired by his experience as a father. He would come home from work and ask his kids if they had brushed their teeth. They said “yes,” but Serval would find their toothbrush heads dry. He decided he needed a brush that really told him how well his children brushed.

    The company says the Kolibree will go on sale this summer, for $99 to $199, depending on features. The U.S. is the first target market.

    Serval says that one day, it'll be possible to replace the brush on the handle with a brushing unit that also has a camera. The camera can even examine holes in your teeth while you brush.

    My husband Jeff and I moved into our new home in Scottsbluff last year just before Christmas. I did not have the time or energy to carry out my traditional Christmas decorating and baking activities. What was the point, anyway? It was going to be a lonely Christmas after all.

    However, the neighborly nature of west Nebraska residents started to trickle (陆续来临) in.

    There was a knock on the door one evening. It was Jeff's new colleague, John Smith, and his wife, Phyllis. The Smiths had stopped by to welcome us to town with a loaf of homemade bread. They pointed out a package on the porch (门廊). Apparently the doorbell wasn't working in the cold snowy weather and we had missed a visit from the Browns, our across-the-street neighbors, who brought us a Christmas card and more Christmas cookies.

    Then, we received an invitation to share a Christmas Eve meal with our neighbors, Ernie and Nancy Sommer, and their guest—a 90-year-old lady, who also had no family in the immediate area with whom to spend the holiday.

    I was so grateful for these gestures of welcome, especially during the holidays.

    This year, we were again unable to be with our families for Christmas. The distance and work schedules just made things too difficult. Knowing that sense of Christmas isolation all too well, we decided to try to round up some other folks who were alone in the holidays.

    Lonely people are all around us, but most of us seldom notice them. Just take a look around you. Sometimes, the smallest kind gesture can make a world of difference.

    Ask someone what they have done to help the environment recently and they will almost certainly mention recycling. Recycling in the home is very important of course. However, being forced to recycle often means we already have more material than we need. We are dealing with the results of that over-consumption in the greenest way possible, but it would be far better if we did not need to bring so much material home in the first place.

    The total amount of packaging(包装) increased by 12% between 2010 and 2015. It now makes up a third of a typical household's waste in the UK. In many supermarkets nowadays food items are packaged twice with plastic and cardboard.

    Too much packaging is doing serious damage to the environment. The UK, for example, is running out of it for carrying this unnecessary waste. If such packaging is burnt, it gives off greenhouse gases which go on to cause the greenhouse effect. Recycling helps, but the process itself uses energy. The solution is not to produce such items in the first place. Food waste is a serious problem, too. Too many supermarkets encourage customers to buy more than they need. However, a few of them are coming round to the idea that this cannot continue, encouraging customers to reuse their plastic bags, for example.

    But this is not just about supermarkets. It is about all of us. We have learned to associate packaging with quality. We have learned to think that something unpackaged is of poor quality. This is especially true of food. But it also applies to a wide range of consumer products, which often have far more packaging than necessary.

    There are signs of hope. As more of us recycle, we are beginning to realise just how much unnecessary material we are collecting. We need to face the wastefulness of our consumer culture, but we have a mountain to climb.

    Joanna Cole, born on August 11, 1944 in Newark, New Jersey, has been credited to be one of the most popular children's authors of all time. She has written over 250 books and is famous for writing one of the most popular children's book series. She knew as early as 5th grade that she was interested in writing and science. Cole has owed a large part of her passion to one of her elementary school teachers.

    Joanna Cole continued her education by attending the University of Massachusetts and Indiana. She would eventually earn a bachelor's degree in psychology from the City College of New York in 1967; after graduation Cole decided to take some education courses to become a librarian at a Brooklyn elementary school in 1967. Eventually, she would take jobs working for Newsweek, Seesaw book club.

    Cole's passion for writing and science was still alive and well during this time. In 197l she decided to write her first book, Cockroaches. She did some research and discovered there had never been a book written for children about cockroaches. So she thought she would be the first.

    Cole struck gold when she wrote the first Magic School Bus in 1985. The book would go on to be published the following year and quickly became book series and cartoon series due to its success.

    Cole continued to write both non-fiction and fiction books for children. She writes in a way that will hopefully inspire children to think like a scientist. She does this by writing ideas instead of just facts. She also tries to ask questions in her books that require children to think and discover the answers as they read. This creates an engaging experience for children, so it is no wonder why younger readers are hooked on her books.

    A recent study led by researchers from the National University of Singapore (NUS) has found a clear link between the color of a taxi and its accident rate. An analysis of 36 months of detailed taxi, driver and accident data from two fleets of yellow and blue taxis in Singapore suggested that yellow taxis have fewer accidents than blue taxis. The higher visibility (能见度)of yellow makes it easier for drivers to avoid getting into accidents with yellow taxis, leading to a lower accident rate.

    The study was led by Prof Ho. To test whether there was a causal relationship between the color of a taxi and the number of accidents the taxi had, the research team analysed data collected by the largest taxi company in Singapore. The researchers found that yellow taxis have about 6.1 fewer accidents per 1,000 taxis per month.

    The researchers also studied the economic effect of changing the color of the entire fleet of taxis to yellow. The Singapore taxi company involved in the study owns about 16,700 taxis in a ratio(比例) of one yellow to three blue taxis. If a commercial decision is made to switch from blue to yellow taxis, 76.6 fewer accidents would occur per month or 917 fewer accidents per year. Assuming an average repair cost of $1,000 per car and a downtime of six days, switching the color of all taxis to yellow could produce an annual savings of $2 million.

    "We are eager to continue to validate(证实) the findings of our study by looking at the use of yellow in other types of public transport, such as school buses. For instance, we hope to compare the accident rates of yellow school buses against other colors to find out if yellow is indeed a safer color for school buses. Besides, we are also interested to look at private-hire vehicles and do a comparison of the accident rates of vehicles that are of different colors," explained Prof Ho.