In the future, you may not have to give your heart to your loved one on Valentine’s Day — researchers are working to develop functional 3D-printed organs instead. That’s in this week’s coolest scientific discoveries, which also includes neurostimulated monkeys, energy-neutral greenhouses and robots feeling their way into the future.
What is it? Brain researchers at the University of Wisconsin-Madison placed monkeys under heavy sedation — like humans during surgery — then were able to bring them rapidly back to consciousness by applying a small amount of electricity to a certain area of their brains.
Why does it matter? The findings could be used to advance treatment methods for brain disorders including coma, according to a news release from UWM, which said the results “isolate a particular loop of activity in the brain that is crucial to consciousness.” For the monkeys, it was a bit like flipping a switch. Psychology and neuroscience professor Yuri Saalmann said, “For as long as you’re stimulating their brain, their behavior — full eye opening, reaching for objects in their vicinity, vital sign changes, bodily movements and facial movements — and their brain activity is that of a waking state. Then, within a few seconds of switching off the stimulation, their eyes closed again. The animal is right back into an unconscious state.”
How does it work? Saalmann and colleagues focused on the central lateral thalamus, where lesions have been linked to “severe consciousness disruption like coma.” The researchers tried to match their stimulation to the frequency of the central lateral thalamus during conscious activity, said Michelle Redinbaugh, first author of a study describing the results in Neuron: “A millimeter out of position, and you dramatically reduce the effect. And if you’re in that ideal location, but stimulating at two Hertz instead of 50? Nothing happens. This is very location- and frequency-specific.” The researchers were then able to observe how stimulation of the central lateral thalamus stimulated, in turn, parts of the cortex, a region of the brain thought to be a key part of consciousness.
What is it? Plants in greenhouses absorb only some wavelengths of light; the rest goes unused. It could, however, be captured by transparent solar panels on greenhouse roofs, according to new modeling done by researchers at North Carolina State University.
Why does it matter? That could help greenhouses — which require electricity for, among other things, heating and cooling — become energy-neutral, requiring no external source of power. There’s a bit of a trade-off, though, because the solar panels capture at least a portion of the photosynthetic light feeding the plants; what the NCSU researchers demonstrated is that, for greenhouse operators, the energy gains might be worth any photosynthetic losses.
How does it work? “We’re able to do this by using organic solar cells, because they allow us to tune the spectrum of light that the solar cell absorbs,” said NCSU engineering professor Brendan O’Connor. “So we can focus on using mostly wavelengths of light that plants don’t use. However, until now it wasn’t clear how much energy a greenhouse could capture if it was using these semitransparent, wavelength-selective, organic solar cells.” O’Connor et al modeled the use of such solar cells on tomato-growing greenhouses in North Carolina, Wisconsin and Arizona and estimated that in Arizona, for instance, a greenhouse could become energy-neutral by using panels that block only 10% of the photosynthetic band of light. The research is described further in the journal Joule.
What is it? At the Massachusetts Institute of Technology, researchers developed a soft robotic arm that can “understand its configuration in 3D space, by leveraging only motion and position data from its own ‘sensorized’ skin.”
Why does it matter? In the 1999 M. Night Shyamalan movie, the “sixth sense” referred to the ability to communicate with dead people, but here in the real world the phrase is often used to describe proprioception: The true sixth sense is the way that animals understand our location in and movement through three-dimensional space. If robots are going to move in the world autonomously, engineers figure, they (and we) will be safer if 1) they’re soft rather than hard, and 2) they can independently figure out where they’re going. That requires them to be programmed with at least some degree of proprioception.
How does it work? Researchers developed a system of soft sensors that cover a robot’s body, feeding the information into a deep-learning model that yields an estimate of the object’s position in 3D space. They demonstrated the concept on a soft robotic arm that “can predict its own position as it autonomously swings around and extends,” according to MIT. Daniela Rus, director of MIT’s Computer Science and Artificial Intelligence Laboratory, said, “Think of your own body: You can close your eyes and reconstruct the world based on feedback from your skin. We want to design those same capabilities for soft robots.”
What is it? At Switzerland’s Ecole Polytechnique Fédérale de Lausanne, engineers developed an entirely new method of 3D-printing small, soft objects. It yields highly precise results — and fast.
Why does it matter? The EPFL team behind the technology envisions a wide range of uses for it, but says it could be particularly well-suited to biomedical applications, like 3D-printed tissue, organs and hearing aids. Plus, the printing can be done inside sealed and sterile containers, a boon for anyone using the technology for medical purposes. The process takes less than 30 seconds and is precise down to 80 micrometers, or about the diameter of a strand of hair.
How does it work? In some industrial 3D printing applications, an object is built by using a laser to fuse powder, layer by layer, into a predetermined shape. The EPFL method relies on laser, too, but this laser is beamed into a container holding a translucent gel. “It’s all about the light,” said Paul Delrot, co-author of a new paper in Nature Communications. “The laser hardens the liquid through a process of polymerization. Depending on what we’re building, we use algorithms to calculate exactly where we need to aim the beams, from what angles, and at what dose.”
What is it? Over in Munich, meanwhile, scientists found a way to “make intact human organs transparent,” enabling the 3D mapping of such organs — and perhaps as a result, the eventual 3D printing of artificial organs for patients in need.
Why does it matter? Organ shortages are a persistent problem, with scientists around the world hoping to find solutions by reducing the need for entirely new organs or by finding organs that don’t require donors — that is, artificial ones. Ali Ertürk, director of the Institute for Tissue Engineering and Regenerative Medicine at Helmholtz Zentrum München, said, ”There is a huge shortage of organ donors for hundreds of thousands of people. The waiting time for patients and the transplantation costs are a real burden. Detailed knowledge about the cellular structure of human organs brings us an important step closer to creating functional organs artificially on demand.” Ertürk is the co-author of a new paper in the journal Cell.
How does it work? The European researchers first discovered that a new kind of detergent could make small holes through the entirety of human organs obtained post-mortem — making their structures transparent — then paired the process with a new laser-scanning microscope; together, the techniques yielded clear, detailed images. They’re working on obtaining 3D images of organs including the heart, pancreas and kidney; such snapshots could serve as blueprints for scientists attempting to develop artificial organs.