With the ocean covering more than 70% of the Earth's surface, the National Oceanic and Atmospheric Administration（NOAA）said scientists and researchers had depended on sonar（声呐）technologies to understand and map the sea floor which had charted only about 10% of the world's ocean. For the ocean and coastal waters in the US, the number is just around 35%.

We know less about our planet's ocean than what we know about the far side of the moon or the surface of Mars. Part of the reason for the lack of observation is the challenge of powering an underwater camera. Researchers have used ships to recharge cameras or observed with a camera tied to a ship to solve the issue, which is expensive and unsuitable for long-term observations.

Recently, researchers at the Massachusetts Institute of Technology（MIT）have taken a major step to iron out this problem by developing a battery-free, wireless underwater camera that could harvest energy underwater on its own for long periods.

To keep power consumption as low as possible, the researchers used off-the-shelf, ultra-low-power imaging sensors. The device takes color photos, even in dark underwater environments, and sends image data wirelessly through the water.

The camera is powered by sound. It changes mechanical energy from sound waves traveling through water into electrical energy that powers its imaging and communications equipment. After getting and encoding image data, the camera also uses sound waves to send the data to a receiver that reconstructs the image. Those sound waves could come from any source, like a passing ship or marine life. As it doesn't need a power source, the camera could run for weeks on end before getting it back, enabling scientists to search remote parts of the ocean for new species.

Now that researchers have demonstrated a working prototype（原型）, they plan to enhance the device so it is practical in real-world settings. For future application, these cameras may be used to take images of ocean pollution and create more accurate models to monitor climate change to better understand how climate change impacts the underwater world, and advance various undersea scientific fields.

Foods high in sugar are unhealthy, but these additives are too delicious for many of us to give up or reduce in a way. What if we could somehow enjoy their taste without actually eating them? A student team has now designed a spoon with a structure that stimulates taste buds（味蕾）to produce a sense of sweetness without adding calories or chemicals. The project follows previous work involving flavor-enhancing cutlery like chopsticks that increase sweetness with a mild electric current. 

The five undergraduate and graduate research students wanted to create a new spoon called Sugarware for people with such disorders as diabetes, with which sugar is largely off their menu. 

The new spoon would have several bumps（凸起） on its underside to press against the tongue. The bumps can be covered with a permanent layer of molecules（分子）called ligands. These ligands bond with taste-cell receptor proteins that typically react to sugar molecules or artificial sweeteners. The bond can activate nerve signals, causing the brain to register a sense of sweetness. A diner could thus stimulate sweetness receptors without actual intake of sugar or artificial sweeteners. 

This idea is similar to the previous work in that they all use cutlery to enhance taste without a user having to actually consume any sugar. "But the mechanism for stimulating the taste buds is completely different, " Shiyu Xu, one of the student researchers, says, " It uses bumps and taste-bud-stimulating molecules rather than electricity. "

The idea is "very creative, " says Paola Almeida, who is the global director of corporate innovation at candy maker Mars. But the product's commercial success would require a significant behavioral shift among consumers: instead of adding the usual sugar or artificial sweeteners, " now we're saying. 'Use this cutlery. '" Almeida says, "It remains to be seen whether flavor-enhancing cutlery will catch on. "

When American Matt Stopera's iPhone went missing, he thought, "Well, bad luck. These things happen." One year later, Matt's misfortune has turned to good fortune as he found a new friend and became an Internet celebrity in China.

You may already be familiar with this story since it spread on Weibo for weeks during the Spring Festival, but it started when Matt began seeing photos of a Chinese man in front of an orange tree on his photo stream（照片流）. He wrote about it and some Chinese readers decided to see if they could find the mysterious man. They did. It turns out that "Brother Orange," as he became known, owned a restaurant in Guangdong and the iPhone he was using, a gift from a nephew, was Matt's old phone.

Matt and Brother Orange began messaging each other and a friendship blossomed with Matt invited to China to feast at Brother Orange's restaurant on his delicious Hakkacuisine（客家菜）. Matt was also overwhelmed by the warmth of the millions of Chinese who were following the story. When he opened a Weibo account he had 22 million followers almost overnight, many of them inviting him to their hometowns and offering to be his tour guide.

Matt's story is another example of how powerful the Internet and social networking has become in bringing people together. But there is a darker side to this story and that involves how Matt's missing iPhone turned up in China. Over three million smart-phones were stolen in America last year. Because of identification numbers, these phones can't be used in America, so they are sent to other countries and many of them end up in China, where they can be re-activated. This is why Matt and Brother Orange could share the same iCloud account.

You should keep this in mind when buying a second-hand phone and check the serial number to see that it has not been stolen. Finding a friend through social networking is wonderful, but using a stolen phone isn't really the best way to make the connection.