Now, chemists have discovered new potential in abundant building blocks: Through a series of reactions, scientists have shown that conventional bricks can be transformed into energy storage devices powerful enough to turn on LED lights. “What we have demonstrated in our paper is sufficient enough for you to light up emergency lighting that's in a hallway or sensors that could be put inside the walls of a house, "said Julio M. D’ Arcy, an assistant professor of chemistry at Washington University in St. Louis, Missouri, and one of the study's authors. "The next step is trying to store more energy, so that you can power bigger devices--like maybe a laptop--directly from the walls of the house. ”

“Bricks have been prized by architects for their capacity to store heat, but using them to hold electricity has never been tried before, "D'Arcy said. To allow the bricks to store electricity, the researchers pumped a series of gases inside the brick. "The gases react with the brick's chemical components, coating them with a web of plastic nanofiber (纳米纤维）known as a PEDOT, which is a good conductor of electricity, "he said. Though PEDOT can store large amounts of energy, this supercapacitor (超级电容器）cannot hold onto that charge or deliver sustained energy over long periods of time like batteries can. “A battery will give you energy density that will allow you to drive 300 miles, but a supercapacitor will allow you to accelerate very quickly at a red light,” D’ Arcy said.

Still, scientists see potential in the bricks as a possible green energy solution. Right now, these "smart bricks" cannot compete with the energy storage potential of the lithium-ion (锂离子）batteries used in many solar power systems. However, there is hope that this new technology could be developed to provide a new storage method using readily available materials.

“The performance is a long way short of custom-made supercapacitors, but the principle is proven and there is significant room for improving the storage characteristics by optimizing the structure and chemistry of the bricks,” said Dan Brett, a professor of electrochemical engineering at University College London, who was not involved in the study.

Scientists from Tufts University have developed tiny groups of human cells that can move on their own-and in a lab experiment, these so-called “anthrobots” inspired sheets of human neurons to repair themselves when damaged. The researchers hope the collections of cells could one day be used to treat diseases or aid with healing in humans.

The study comes on the heels of earlier work from one of its authors, who produced tiny robots by stitching together frog embryo cells. These robots, known as “xenobots”, could assemble themselves, move across surfaces and travel through liquid.

Since they're not made from human cells, xenobots can't be used to treat humans, writes Matthew Hutson, a freelance science writer. But the anthrobots in the new study could theoretically. Each anthrobot started with a single cell from an adult human lung. It then grew into a multicellular biobot after being cultured (培养) for two weeks.

These lung cells are covered in cilia. But at this point in the research, the cilia were growing inside the clumps of cells. So, for the next week, the researchers grew the cells in a solution (溶液) that caused the cilia to face outward instead, enabling these structures to move the anthrobots, which could move in tight loops, travel in straight lines or wiggle in place. Their speed varied as well.

The researchers also tested how these robots might heal wounds. They mimicked (模拟) a wound by scratching a layer of neurons in a dish. Then, they introduced anthrobots to the site of the scratch, and within days, the neurons regrew, bridging the gap created by the wound. The findings show new structures that might have uses in biomedical settings can be developed without gene editing and without having to design the structures manually, the study authors write.

“Unlike xenobots, anthrobots don't require tools to give them shape, and we can use adult cells-even cells from elderly patients-instead of embryonic cells,” says Gizem Gumuskaya, the paper's lead author. "We can produce these robots in large amounts in parallel, which is a good start for developing a therapeutic tool.”

The days of having to carry a phone charger everywhere could soon be over. Michigan researchers have revealed a major breakthrough in harvesting energy from human motion. They say it could lead to smartphones powered for a week by the motion of a swipe(重击).

Michigan State University’s low-cost device, known as a nanogenerator, has already been tested. Scientists successfully operated an LCD touch screen, a bank of 20 LED lights and a flexible keyboard, all with a simple touching or pressing motion and without the aid of a battery. The groundbreaking findings, published in the journal Nano Energy, suggest “We’re on the path toward wearable devices powered by human motion,” said Nelson Sepulveda, associate professor of electrical and computer engineering and lead researcher of the project.

“What I foresee, relatively soon, is the capability of not having to charge your cell phone for an entire week, for example, because that energy will be produced by your movement,” said Sepulveda, whose research is funded by the National Science Foundation.

Electrical energy is created when the device is compressed by human motion. The completed device is as thin as a sheet of paper. The device used to power the LED lights was palm-sized, while the device used to power the touch screen was as small as a finger. Advantages such as being lightweight, flexible and low-cost could make it a promising and alternative method in the field of Mechanical-energy harvesting.

The device also becomes more powerful when folded. Sepulveda said, “You can start with a large device, but when you fold it once, and again, and again, it’s much smaller and has more energy. Now it may be small enough to put in a specially made heel of your shoe so it creates power each time your heel strikes the ground.”

Sepulveda and his team are also developing technology that would transmit the power generated by the heel strike to, say, a wireless headset.