Our warming planet is expected to face serious water crisis（危机）in the coming decades — which means each nation's natural resource will be more important than ever.

    Kenyon Scudder once told me a story about his friend, Michael. Michael happened to be on a train sitting next to a young man who seemed worried. Finally the young man told the friend that he was a convict (罪犯) returning home from a prison for away. What he did had brought shame on his family, and they had neither visited him nor written to him. He hoped, however, that this was only because they were too poor to travel and too busy to write.

    When he was set free he had written to tell them he wanted to go home. To make matters easy for them, however, he had asked them to put up a signal (信号) for him when the train passed their little form. If the family had forgiven (原谅) him, they were to put up a white ribbon (丝带) in the big apple tree near the railway. If they didn't want him back, they were to do nothing, and he would stay on the train, and go far away.

    As the train neared his hometown, his suspense became so great that he was afraid to look out of the window. He asked Michael to watch for the big apple tree. They changed seats. In a minute, Michael put his hand on the young convict's shoulder. “There it is,” he said, his eyes filled with sudden tears. “It's all right. The whole tree is white with ribbons.”

    Don't you just hate it when you have to take an important phone call and you're surrounded by potential eavesdroppers(潜在偷听者)? You either have to whisper or go outside to keep the conversation private, which is not good. Now Hushme aims to fix this problem by muffling your voice and making you look like Bane in the film Batman.

    Hushme is a strange high-tech mask(口罩)that blocks the sound of the wearer's voice so that people nearby can't hear what is being said. It connects to your phone via Blucetooth and comes with a pair of earphones. When you get a private call, all you have to do is put the mask on and it will do the rest. The pair of thick pads over your mouth does a good job of muffling your voice, but to ensure nothing gets through. Hushme also has speakers that play a variety of sounds when you speak.

    The Hushme mask, which comes in a variety of colors, can be worn around the neck, like a regular pair of earphones, and attaches in front of your mouth thanks to a couple of very powerful magnets(磁铁). It's not yet clear how comfortable speaking with this Bane-like mask over your mouth really is, or how effective its speech muffling ability is, so we know so far is that it makes you look strange. The sound choices for covering your voice currently include wind, ocean, rain, birds, monkey, but new ones could be added in the future.

    Advertised as the “world's first voice mask for mobile phones'. Hushme was showed at CES. At the becoming of this year. Its makers plan to sell it by the end of this year. It will cost about $200.

    I was playing in my kitchen. My mom stood in front of me, hardly keeping the tears from spilling over. She told me that my little cousin had cancer. Hearing this, I went completely numb. How could this be happening? I had just seen her, and she was fine.

    These things didn't happen to our family, that's what my uncle said. It seemed like the world turned upside down; just last week my grandmother had passed away. I felt like I couldn't get my feet on solid ground.

    That's when my sister, Ella, came down the stairs with her long brown hair freshly washed. She sat next to me and smiled. Despite what was happening, everything would work out, her smile seemed to say.

    “Mom, do you think I could get my hair cut tomorrow?” Ella asked.

    “Sure,” Mom said, starting to wash the dishes.

    “I want to donate it to Locks of Love” Ella smiled.

    My mom stopped washing and turned to look at her. “Are you sure?” I noticed that Mom was holding back tears. This was a sacrifice(牺牲) for Ella. Her long hair was an important part of her.

    “Yeah, it's just hair. Eventually it will grow back.” She said.

    “All right,” Mom said quietly, smiling again.

    Ella gave up a part of herself for a while. She let a piece of herself go to someone else, someone she didn't know. That day she became my hero too.

    Traditionally, robots have been hard, made of metal and other rigid material. But a team of scientists at Harvard University in the US has managed to build an entirely soft robot-one that draws inspiration from an octopus (章鱼).

    Described in science journal Nature, the "Octobot" could pave the way for more effective autonomous robots that could be used in search，rescue and exploration. "The Octobot is minimal system which may serve as a foundation for a new generation of completely soft, autonomous robots" the study's authors wrote.

Robots built for precise, repetitive movements in a controlled environment don't do so well on rough terrains (地形) or in unpredictable conditions. And they aren't especially safe around humans, because they're made out of hard and heavy parts that could be potentially dangerous to their users.

    So researchers have been working on building soft robots for decades. They're taken inspiration from nature, looking to animals from jellyfish to cockroaches, which are often made up of more flexible matter.

    But creating a completely soft robot remains a challenge. Even if engineers build a silicone (硅酮) body, it's still a grand challenge to construct flexible versions of essential parts, such as a source of power.

    "Although soft robotics is still in its early stage, it holds great promise for several applications, such as search-rescue operations and exploration," Barbara Mazzolai and Virgilio Mattoli of the Italian Institute of Technology' Center for Micro-BioRobotics, wrote in a comment. "Soft robots might also open up new approaches to improving wellness and quality of life."

Do you continue to be healthy in social isolation? NASA is looking for people to spend 8 months locked in a Russian lab for a new experiment.

When humans go to the moon and travel to Mars, they will need to be prepared for long-term space travel and even longer stays on these far-off destinations. Currently, NASA's Artemis program aims to land humans on the moon for the first time since NASA's Apollo 17 mission landed in 1972.

While the moon is the main goal of NASA's Artemis program, the agency's larger goal is to send people to Mars. But long-term space travel and habitation won't be easy. Such missions will present both physical and mental challenges as astronauts work to not only survive, but perform important scientific research in uniquely difficult environments.

In the upcoming NASA-Russia experiment, a group of people will live in a closed facility at Russia's Institute for Biomedical Problems, which is in Moscow. This habitat facility was used in2011 for notable series of Russian mock (模拟的) Mars missions known as Mars 500. During these missions, groups of people spent 520 and 105 days on two separate missions in the facility.

The facility, according to the statement, will have "environmental factors similar to those astronauts are expected to experience on future missions to Mars". The group of people will spend 8 months living together in isolation and working on scientific research.

By living and working in this Mars-like environment, participants in this study will help NASA researchers better understand the psychological and physiological (心理和生理的) effects of isolation. These missions help researchers not only perform relevant science experiments but also see how people might get on under strange conditions for long periods of time.

So, if you're finding that living in social isolation works for you, you might be particularly well-suited for living in a Mars-like environment and this could be for you. But first, you have to qualify. NASA is looking for "highly motivated" Americans between the ages of 30-55, who must speak both Russian and English fluently and have a Master of Science, Doctor of Philosophy, Doctor of Medicine, or military officer training. Applicants with other related experience may also be considered. Those who are chosen to be a part of this group will be paid for their work.