【推荐2】On the farm in a red outbuilding behind Luther Jackson Middle School, Mark Smith picked a piece of cabbage off the plant and took a bite.

“Tastes like victory,” he said, satisfied.

Fifteen engineering students at the school, led by Smith, their engineering teacher, have developed and built the farm using aquaponics (鱼菜共生) technology, combining the methods of hydroponics, growing plants with water rather than soil, and aquaculture, the process of growing and raising fish. The fish waste is used as food for the plants, which filter(过滤) the water to be reused in the fish tank.

“The creative project was put forward by the students,” Smith says. “Effectively combining technology with education, it serves to provide a unique learning experience, involving students in core STEM subjects like Math, Biology, Chemistry and Engineering. It’s our hope that it can help increase students’ interest and hands-on skills so that more students will be inspired and choose to take up engineering as their career in the future.”

Not only can students study fish, plants and bacteria (细菌) interacting in a living ecosystem, but they’re also in charge of every aspect of developing and keeping the farm, from ordering supplies to harvesting the greens. Camryn, 14, put a test tube into the fish tank and dropped some chemicals to test PH levels and some substances in it, She held the tube up to light, watching the color.

Behind her, Yusuf worked along a table with other students to harvest the cabbage, stuffing the leaves into bags to deliver later that afternoon to about 70 families. For him, the ability to give back to his community is the best part of the project.

“We should all be proud of ourselves,” Yusuf said, “We’re making stuff that people are going to be eating.”

【推荐3】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 dentist 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 on your phone, so developers could, for instance, create a game controlled by your toothbrush. You could score points for beating monsters 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.

【推荐2】For centuries, humans have explored the Earth’s mountains, jungles and deserts. But despite covering more than 70% of the Earth’s surface, the ocean is still a relative mystery. In fact, just over 20% of the ocean bed has been mapped. Getting a fuller picture would enable us to guide ships more safely, build wind-farms and protect ocean species—all part of what’s known as the “blue economy”, projected to be worth $3 trilling by 2030.

Underwater robotic vehicles are helping gather that data quicker and more cheaply than ever before. But many of these vehicles depend on batteries which need to return to a boat or the shore to recharge, making it difficult to map more remote (遥远的) parts of the sea.

A startup called Seatrec is rising to the challenge, founded by oceanographer Yi Chao. Yi Chao developed technology to power ocean robots by taking advantage of “the naturally temperature difference” between colder and warmer parts of the sea, which in turn creates energy and powers the robot’s generator (发电机). They get charged by the sea, so their lifetime will be almost limitless,” Chao said.

The power module (组件) can be fixed on existing data-gathering robots which dive a kilometer down to examine the chemistry and shape of the seabed, creating a map of the surrounding area. The robot returns to the surface to send back its findings via satellite. A basic power module costs as much as $20,000. But the access to free, renewable energy and the ability to stay in the water longer make data gathering up to five times cheaper in the long run.

Started in 2017, the Seabed 2030 Project has increased awareness about the importance of the ocean floor and given researchers and companies a clear goal to work towards: map the entire seafloor by the end of this decade.

【推荐3】When did you last write a letter? Properly write one—by hand? In a digital world, where sending a text or email is far more convenient than using snail mail, is the writing on the wall for traditional pen and paper?Well,some people claim that writing still has many benefits, so maybe it’s not time to forgo your ballpoint or fountain pen yet.

These days, when people request things in writing, a typed, electronic document will be accepted. Doing this on a computer means it could be saved, edited, copied and sent via email. But crafting a handwritten document is unique; It requires planning and thought, and, as well as practising your handwriting, it helps you to remember spelling and punctuation.

Some experts believe your brain benefits from using old-fashioned pen and paper. This is particularly relevant for students, where typing notes into a laptop is thought to lack the “tactile feedback(触觉反馈)”to the brain that contact between pen and paper does. BBC Work life website quotes Hetty Roessingh from the University of Calgary, who says that taking notes by hand involves cognitive engagement in summarizing, paraphrasing, organizing, concept and vocabulary mapping. Others agree that handwriting may boost fine motor skills in your hands and fingers.

There are everyday benefits of using pen and paper too. Scribbling(匆忙书写)notes，shopping lists or messages on the back of an envelope can still be useful, quick and portable. But putting pen to paper in a letter to a friend cor loved one can probably have the most impact. Pen pal writer Katherine Moller told the BBC, “In a world where it is so easy to hop online to email or to send a fast text, it is so personal and so precious to know someone chose to turn off the virtual world to spend some time with you.”

So, while digital skills remain important, don’t write off your pens and pencils yet—especially if your smartphone, tablet or laptop runs out of power.

【推荐2】It is generally believed that we are getting cleaned when we step under a shower. We are, but we’re also giving a home to lots of tiny little creatures we didn’t even know about. A showerhead (淋浴喷头) carries thousands of bacteria (细菌) called Mycobacterium. These can cause problems like coughs and tiredness, and a general feeling of poorliness (身体不舒服). When you turn on the water, the bacteria go from the showerhead onto and into your body.

This is a finding of Norman R. Pace and his team at the University of Colorado, in the US. The scientists investigated bacteria in all kinds of human environment, including showers. Pace's team looked at 45 showerheads in nine American cities. They discovered that 30 percent of them had large amounts of flying Mycobacterium.

But Pace said that they pose few threats to the health. Only those with a weak immune system might need to worry. He told the New York Times that the bacteria are not as unpleasant as might be thought. He said that having a shower is no more dangerous than anything else we do in the morning.

But for those who feel sick about the idea of all those microorganisms (微生物), he had some advice. Let the water run for 30 seconds before getting into the shower. Why? The number of bacteria is smaller than that when the water is just turned on. If that seems like a waste of water, he added that you could also change your showerhead every few months.

However, Pace had good news too. He has also been testing the air in US subways. Apart from iron particles (粒子), which are ground off the track by the wheels of trains, subway air is fresh. The reason is that a train’s movement pumps fresh outdoor air into the tunnels.

Pace explained that he wanted to understand the natural microbial environments of public places. This kind of knowledge might help discover the microbes (细菌) to be used in a bioterrorist (生物恐怖分子) attack.

【推荐3】With the Internet, people can send and receive e-mails. On the Internet, people can skim over news. Using the Telnet, the user anywhere on the Internet can log into any other machine on which he has an account. It is possible to use the FTP program to copy files from one machine on the Internet to another.

But the Internet also brings us troubles.

Internet use seems to cause a fall in psychological health, according to research at Carnegie Mellon University. Even people(who spent just a few hours a week on the Internet) experienced more depression and loneliness than those who logged on less often, the two-year study showed. And it wasn’t that people who were already feeling bad spent more time on the Internet, but that using the Net actually seemed to cause the bad feelings.

Researchers are puzzled about the results, which were completely opposite to what they had expected. They expected that the Net would prove socially healthier than television, since the Net allows users to choose their information and to communicate with others.

The fact that Internet use reduces time that was used for family and friends may be the reason for the drop in health, researchers said. Faceless, bodiless “virtual” (communication may be less psychologically satisfying than actual conversations, and the relationships formed through it may not be so deep. Another possibility is that exposure to the wider world through the Net makes users less satisfied with their lives.

“But it’s important to remember this is not about the technology; it’s about how it is used,” said one of the researchers. “It really points to the need for considering social factors when you design new inventions.”