Posts Tagged ‘technology’

A tetraplegic man has been able to move all four of his paralyzed limbs by using a brain-controlled robotic suit, researchers have said.

The 28-year-old man from Lyon, France, known as Thibault, was paralyzed from the shoulders down after falling 40 feet from a balcony, severing his spinal cord, the AFP news agency reported.

He had some movement in his biceps and left wrist, and was able to operate a wheelchair using a joystick with his left arm.

Researchers from the University of Grenoble in France, biomedical research center Clinatec and the CEA research center implanted recording devices on either side of Thibault’s head, between the brain and skin, to span the sensorimotor cortex — the area of the brain that controls motor function and sensation.

Electrode grids collected the man’s brain signals and transmitted them to a decoding algorithm, which translated the signals into movements and commanded a robotic exoskeleton to complete them.

Over a period of two years, Thibault trained the algorithm to understand his thoughts by controlling an avatar — a virtual character — within a video game, making it walk and touch 2D and 3D objects.

He trained on simple virtual simulations before using the exoskeleton — which is assisted by a ceiling-mounted harness — to eventually walk, and reach for targets with his arms.

Over the course of the study, Thibault covered a total of 145 meters (around 476 feet) with 480 steps using the avatar, video and exoskeleton combined, researchers said in the study, which was published in the Lancet Neurology journal on Friday.

Scientists have said that the technology is an experimental treatment for now, but once improved, it could have the potential to improve patients’ lives.

“I can’t go home tomorrow in my exoskeleton, but I’ve got to a point where I can walk. I walk when I want and I stop when I want,” Thibault told AFP.

“Our findings could move us a step closer to helping tetraplegic patients to drive computers using brain signals alone, perhaps starting with driving wheelchairs using brain activity instead of joysticks and progressing to developing an exoskeleton for increased mobility,” Professor Stephan Chabardes, a neurosurgeon from Grenoble University Hospital and author of the study, said in a press release.

The team has recruited three more patients to the trial, and aims to allow patients to walk and balance without using a ceiling suspension system in the next phase of the research.

Reversing baldness could someday be as easy as wearing a hat, thanks to a noninvasive, low-cost hair-growth-stimulating technology developed by engineers at the University of Wisconsin-Madison.

“I think this will be a very practical solution to hair regeneration,” says Xudong Wang, a professor of materials science and engineering at UW-Madison.

Wang and colleagues published a description of the technology in the journal ACS Nano.

Based on devices that gather energy from a body’s day-to-day motion, the hair-growth technology stimulates the skin with gentle, low-frequency electric pulses, which coax dormant follicles to reactivate hair production.

The devices don’t cause hair follicles to sprout anew in smooth skin. Instead they reactivate hair-producing structures that have gone dormant. That means they could be used as an intervention for people in the early stages of pattern baldness, but they wouldn’t bestow cascading tresses to someone who has been as bald as a billiard ball for several years.

Because the devices are powered by the movement of the wearer, they don’t require a bulky battery pack or complicated electronics. In fact, they’re so low-profile that they could be discreetly worn underneath the crown of an everyday baseball cap.

Wang is a world expert in the design and creation of energy-harvesting devices. He has pioneered electric bandages that stimulate wound-healing and a weight-loss implant that uses gentle electricity to trick the stomach into feeling full.

The hair-growth technology is based on a similar premise: Small devices called nanogenerators passively gather energy from day-to-day movements and then transmit low-frequency pulses of electricity to the skin. That gentle electric stimulation causes dormant follicles to “wake up.”

“Electric stimulations can help many different body functions,” says Wang. “But before our work there was no really good solution for low-profile devices that provide gentle but effective stimulations.”

Because the electric pulses are incredibly gentle and don’t penetrate any deeper than the very outermost layers of the scalp, the devices don’t seem to cause any unpleasant side effects. That’s a marked advantage over other baldness treatments, like the medicine Propecia, which carries risks of sexual dysfunction, depression and anxiety.

What’s more, in side-by-side tests on hairless mice, the devices stimulated hair growth just as effectively as two different compounds found in baldness medicines.

“It’s a self-activated system, very simple and easy to use,” says Wang. “The energy is very low so it will cause minimal side effects.”

The researchers have patented the concept with the Wisconsin Alumni Research Foundation, and they hope to move forward with human testing soon.

Story Source:

Materials provided by University of Wisconsin-Madison. Original written by Sam Million-Weaver. Note: Content may be edited for style and length.

Journal Reference:

Guang Yao, Dawei Jiang, Jun Li, Lei Kang, Sihong Chen, Yin Long, Yizhan Wang, Peng Huang, Yuan Lin, Weibo Cai, Xudong Wang. Self-Activated Electrical Stimulation for Effective Hair Regeneration via a Wearable Omnidirectional Pulse Generator. ACS Nano, 2019; DOI: 10.1021/acsnano.9b03912

A group of independent biologists say they plan to copy a costly gene therapy. Are they medicine’s Robin Hood or a threat to safety?

by Alex Pearlman

Citing the tremendous cost of new drugs, an international group of biohackers say they are creating a knock-off of a million-dollar gene therapy.

The drug being copied is Glybera, a gene therapy that was the world’s most expensive drug when it came on the market in Europe in 2015 with a $1 million per treatment price tag. Glybera was the first gene therapy ever approved to treat an inherited disease.

Now a band of independent and amateur biologists say they have engineered a prototype of a simpler, low-cost version of Glybera, and they plan to call on university and corporate scientists to help them check, improve, and test it on animals.

The group says it will start sharing the materials and describe their activities this weekend at Biohack the Planet, a conference in Las Vegas that hosts citizen scientists, journalists, and researchers for two days of presentations on body implants, biosafety, and hallucinogens.

“This was developed in a shed in Mississippi, a warehouse in Florida, a bedroom in Indiana, and on a computer in Austria,” says Gabriel Licina, a biohacker based in South Bend, Indiana. He says the prototype gene therapy cost less than $7,000 to create.

Experts briefed on the biohacking project were divided, with some calling it misguided and unlikely to work. Others say the excessive cost of genetic treatments has left patients without options and created an incentive to pirate genetic breakthroughs.

“It’s a fairly big deal to see biohackers turning their focus to gene therapies because the potential consequences can be quite large,” said Rachel Sachs, an associate professor of law at Washington University in St. Louis and an expert on drug pricing. “They may see themselves as serving the interests of the patient community.”

This year the Swiss pharmaceutical firm Novartis introduced another gene therapy, Zolgesma, for spinal muscular atrophy, with a price of $2.1 million. Because of the cost, some parents have struggled to obtain it for their children and the treatment is unlikely to be made available in most of the world.

Disrupting the narrative

The gene therapy that the biohackers say they are copying, Glybera, was approved for people with an ultra-rare blood disease called lipoprotein lipase deficiency. But it didn’t prove cost-effective and was pulled from the market in 2017 by its manufacturer, UniQure. To date, only one insurer, in Germany, is known to have paid for the treatment.

Andreas Stürmer, a biotechnologist and environmental engineer who is based in Linz, Austria, says after the idea of reverse engineering the treatment occurred to him he brought the concept to Licina. Their collaboration took place through Facebook messages and Skype calls, and included help from David Ishee, a biohacker in Mississippi.

In another recent example of copy-cat gene therapy, a biohacker in Florida in 2018 produced and ate an oral gene therapy for lactose intolerance using a 20-year-old scientific paper as a recipe.

“It’s about disrupting the narrative,” says Licina, also the cofounder of SciHouse, a community biotechnology lab in Indiana. “It was like, ‘Well, why not?”

One reason not to is that copying and selling the drug could infringe on UniQure’s intellectual property. Tom Malone, a spokesperson for UniQure, says the company had not been informed of the biohacking attempt. He says it still owns a patent on the drug but it does not believe there is strong demand for the treatment. “To that end, a “knock off” version of Glybera would likely face significant regulatory and commercial hurdles,” says Malone.

Also, the US Food and Drug Administration has said it is illegal to sell do-it-yourself gene therapy supplies. Still, some biohackers feel confident grabbing information from published papers, even if some of it has been patented. “This thing is protected 10 different ways,” says Ishee. “I don’t care. Because I’m not selling it.”

Get the job done

To make their knock-off, the biohackers checked the original Glybera papers for the information about the genetic sequence of the gene that patients require corrected copies of. They then placed an order with a gene synthesis company for a copy of the DNA, which was added to a circular genetic construct called a “minicircle.” When added to a cell, the mincircle will begin manufacturing small amounts of the lipoprotein lipase enzyme.

That is an important difference from the original Glybera, which employed an injection of viruses into the leg muscle to deliver the gene. Viral “delivery” is a complex undertaking but is the most commonly used strategy in gene therapy. The biohackers don’t have access to viruses because of their high cost, but say minicircles can potentially be injected, too.

Robert Kotin, an expert in gene therapy production, calls the minicircle technology controversial and says it has shown contradictory results. While minicircles, unlike viruses, could possibly be readministered time and again, they are not as efficient in getting cells to follow genetic instructions.

“It’s not the same [but] it can get the job done. It’s just less efficient,” says Ishee of the minicircles, which are based on his design. He thinks they could be injected over a period of half a year. “It’s like if you wanted to dig a swimming pool or a pond—you could buy a backhoe and dig it in a day or you could do it with a shovel at no cost over several months.”

Thanks to Kebmodee for bringing this to the It’s Interesting community.

by Davide Castelvecchi

Long after most chemists had given up trying, a team of researchers has synthesized the first ring-shaped molecule of pure carbon — a circle of 18 atoms.

The chemists started with a triangular molecule of carbon and oxygen, which they manipulated with electric currents to create the carbon-18 ring. Initial studies of the properties of the molecule, called a cyclocarbon, suggest that it acts as a semiconductor, which could make similar straight carbon chains useful as molecular-scale electronic components.

It is an “absolutely stunning work” that opens up a new field of investigation, says Yoshito Tobe, a chemist at Osaka University in Japan. “Many scientists, including myself, have tried to capture cyclocarbons and determine their molecular structures, but in vain,” Tobe says. The results appear in Science1 on 15 August.

Pure carbon comes in several different forms, including diamond, graphite and ‘nanotubes’. Atoms of the element can form chemical bonds with themselves in various configurations: for example, each atom can bind to four neighbours in a pyramid-shaped pattern, as in diamond; or to three, as in the hexagonal patterns that make up the single-atom-thick sheets of graphene. (Such a three-bond pattern is also found in bulk graphite as well as in carbon nanotubes and in the globular molecules called fullerenes.)

But carbon can also form bonds with just two nearby atoms. Nobel-prizewinning chemist Roald Hoffmann at Cornell University in Ithaca, New York, and others have long theorized that this would lead to pure chains of carbon atoms. Each atom might form either a double bond on each side — meaning the adjacent atoms share two electrons — or a triple bond on one side and a single bond on the other. Various teams have attempted to synthesize rings or chains based on this pattern.

But because this type of structure is more chemically reactive than graphene or diamond, it is less stable, especially when bent, says chemist Przemyslaw Gawel of the University of Oxford, UK. Synthesizing stable chains and rings has usually required the inclusion of elements other than carbon. Some experiments have hinted at the creation of all-carbon rings in a gas cloud, but they have not able to find conclusive proof.

One ring
Gawel and his collaborators have now created and imaged the long-sought ring molecule carbon-18. Using standard ‘wet’ chemistry, his collaborator Lorel Scriven, an Oxford chemist, first synthesized molecules that included four-carbon squares coming off the ring with oxygen atoms attached to squares. The team then sent their samples to IBM laboratories in Zurich, Switzerland, where collaborators put the oxygen–carbon molecules on a layer of sodium chloride, inside a high-vacuum chamber. They manipulated the rings one at a time with electric currents (using an atomic-force microscope that can also act as a scanning-tunelling microscope), to remove the extraneous, oxygen-containing parts. After much trial-and-error, micrograph scans revealed the 18-carbon structure. “I never thought I would see this,” says Scriven.

The IBM researchers showed that the 18-carbon rings had alternating triple and single bonds. Theoretical results had disagreed over whether carbon-18 would have this kind of structure, or one made entirely of double bonds.

Alternating bond types are interesting because they are supposed to give carbon chains and rings the properties of semiconductors. The results suggest that long, straight carbon chains might be semiconductors, too, Gawel says, which could make them useful as components of future molecular-sized transistors.

For now, the researchers are going to study the basic properties of carbon-18, which they have been able to make one molecule at a time only. They are also going to keep trying alternative techniques that might yield greater quantities. “This is so far very fundamental research,” Gawel says.

“The work is beautiful,” says Hoffmann, although he adds that it remains to be seen whether carbon-18 is stable when lifted off the salt surface, and whether it can be synthesized more efficiently than one molecule at a time.

doi: 10.1038/d41586-019-02473-z
1. Kaiser, K. et al. Science (2019).

Frank Keutsch, Zhen Dai and David Keith (left to right) in Keutsch’s laboratory at Harvard University.

Zhen Dai holds up a small glass tube coated with a white powder: calcium carbonate, a ubiquitous compound used in everything from paper and cement to toothpaste and cake mixes. Plop a tablet of it into water, and the result is a fizzy antacid that calms the stomach. The question for Dai, a doctoral candidate at Harvard University in Cambridge, Massachusetts, and her colleagues is whether this innocuous substance could also help humanity to relieve the ultimate case of indigestion: global warming caused by greenhouse-gas pollution.

The idea is simple: spray a bunch of particles into the stratosphere, and they will cool the planet by reflecting some of the Sun’s rays back into space. Scientists have already witnessed the principle in action. When Mount Pinatubo erupted in the Philippines in 1991, it injected an estimated 20 million tonnes of sulfur dioxide into the stratosphere — the atmospheric layer that stretches from about 10 to 50 kilometres above Earth’s surface. The eruption created a haze of sulfate particles that cooled the planet by around 0.5 °C. For about 18 months, Earth’s average temperature returned to what it was before the arrival of the steam engine.

The idea that humans might turn down Earth’s thermostat by similar, artificial means is several decades old. It fits into a broader class of planet-cooling schemes known as geoengineering that have long generated intense debate and, in some cases, fear.

Researchers have largely restricted their work on such tactics to computer models. Among the concerns is that dimming the Sun could backfire, or at least strongly disadvantage some areas of the world by, for example, robbing crops of sunlight and shifting rain patterns.

But as emissions continue to rise and climate projections remain dire, conversations about geoengineering research are starting to gain more traction among scientists, policymakers and some environmentalists. That’s because many researchers have come to the alarming conclusion that the only way to prevent the severe impacts of global warming will be either to suck massive amounts of carbon dioxide out of the atmosphere or to cool the planet artificially. Or, perhaps more likely, both.

If all goes as planned, the Harvard team will be the first in the world to move solar geoengineering out of the lab and into the stratosphere, with a project called the Stratospheric Controlled Perturbation Experiment (SCoPEx). The first phase — a US$3-million test involving two flights of a steerable balloon 20 kilometres above the southwest United States — could launch as early as the first half of 2019. Once in place, the experiment would release small plumes of calcium carbonate, each of around 100 grams, roughly equivalent to the amount found in an average bottle of off-the-shelf antacid. The balloon would then turn around to observe how the particles disperse.

The test itself is extremely modest. Dai, whose doctoral work over the past four years has involved building a tabletop device to simulate and measure chemical reactions in the stratosphere in advance of the experiment, does not stress about concerns over such research. “I’m studying a chemical substance,” she says. “It’s not like it’s a nuclear bomb.”

Nevertheless, the experiment will be the first to fly under the banner of solar geoengineering. And so it is under intense scrutiny, including from some environmental groups, who say such efforts are a dangerous distraction from addressing the only permanent solution to climate change: reducing greenhouse-gas emissions. The scientific outcome of SCoPEx doesn’t really matter, says Jim Thomas, co-executive director of the ETC Group, an environmental advocacy organization in Val-David, near Montreal, Canada, that opposes geoengineering: “This is as much an experiment in changing social norms and crossing a line as it is a science experiment.”

Aware of this attention, the team is moving slowly and is working to set up clear oversight for the experiment, in the form of an external advisory committee to review the project. Some say that such a framework, which could pave the way for future experiments, is even more important than the results of this one test. “SCoPEx is the first out of the gate, and it is triggering an important conversation about what independent guidance, advice and oversight should look like,” says Peter Frumhoff, chief climate scientist at the Union of Concerned Scientists in Cambridge, Massachusetts, and a member of an independent panel that has been charged with selecting the head of the advisory committee. “Getting it done right is far more important than getting it done quickly.”

Joining forces
In many ways, the stratosphere is an ideal place to try to make the atmosphere more reflective. Small particles injected there can spread around the globe and stay aloft for two years or more. If placed strategically and regularly in both hemispheres, they could create a relatively uniform blanket that would shield the entire planet (see ‘Global intervention’). The process does not have to be wildly expensive; in a report last month, the Intergovernmental Panel on Climate Change suggested that a fleet of high-flying aircraft could deposit enough sulfur to offset roughly 1.5 °C of warming for around $1 billion to $10 billion per year1.

Most of the solar geoengineering research so far has focused on sulfur dioxide, the same substance released by Mount Pinatubo. But sulfur might not be the best candidate. In addition to cooling the planet, the aerosols generated in that eruption sped up the rate at which chlorofluorocarbons deplete the ozone layer, which shields the planet from the Sun’s harmful ultraviolet radiation. Sulfate aerosols are also warmed by the Sun, enough to potentially affect the movement of moisture and even alter the jet stream. “There are all of these downstream effects that we don’t fully understand,” says Frank Keutsch, an atmospheric chemist at Harvard and SCoPEx’s principal investigator.

The SCoPEx team’s initial stratospheric experiments will focus on calcium carbonate, which is expected to absorb less heat than sulfates and to have less impact on ozone. But textbook answers — and even Dai’s tabletop device — can’t capture the full picture. “We actually don’t know what it would do, because it doesn’t exist in the stratosphere,” Keutsch says. “That sets up a red flag.”

SCoPEx aims to gather real-world data to sort this out. The experiment began as a partnership between atmospheric chemist James Anderson of Harvard and experimental physicist David Keith, who moved to the university in 2011. Keith has been investigating a variety of geoengineering options off and on for more than 25 years. In 2009, while at the University of Calgary in Canada, he founded the company Carbon Engineering, in Squamish, which is working to commercialize technology to remove carbon dioxide from the atmosphere. After joining Harvard, Keith used research funding he had received from Microsoft co-founder Bill Gates, to begin planning the experiment.

Keutsch, who got involved later, is not a climate scientist and is at best a reluctant geoengineer. But he worries about where humanity is heading, and what that means for his children’s future. When he saw Keith talk about the SCoPEx idea at a conference after starting at Harvard in 2015, he says his initial reaction was that the idea was “totally insane”. Then he decided it was time to engage. “I asked myself, an atmospheric chemist, what can I do?” He joined forces with Keith and Anderson, and has since taken the lead on the experimental work.

An eye on the sky
Already, SCoPEx has moved farther along than earlier solar geoengineering efforts. The UK Stratospheric Particle Injection for Climate Engineering experiment, which sought to spray water 1 kilometre into the atmosphere, was cancelled in 2012 in part because scientists had applied for patents on an apparatus that could ultimately affect every human on the planet. (Keith says there will be no patents on any technologies involved in the SCoPEx project.) And US researchers with the Marine Cloud Brightening Project, which aims to spray saltwater droplets into the lower atmosphere to increase the reflectivity of ocean clouds, have been trying to raise money for the project for nearly a decade.

Although SCoPEx could be the first solar geoengineering experiment to fly, Keith says other projects that have not branded themselves as such have already provided useful data. In 2011, for example, the Eastern Pacific Emitted Aerosol Cloud Experiment pumped smoke into the lower atmosphere to mimic pollution from ships, which can cause clouds to brighten by capturing more water vapour. The test was used to study the effect on marine clouds, but the results had a direct bearing on geoengineering science: the brighter clouds produced a cooling effect 50 times greater than the warming effect of the carbon emissions from the researchers’ ship2.

Keith says that the Harvard team has yet to encounter public protests or any direct opposition — aside from the occasional conspiracy theorist. The challenge facing researchers, he says, stems more from a fear among science-funding agencies that investing in geoengineering will lead to protests by environmentalists.

To help advance the field, Keith set a goal in 2016 of raising $20 million to support a formal research programme that would cover not just the experimental work, but also research into modelling, governance and ethics. He has raised around $12 million so far, mostly from philanthropic sources such as Gates; the pot provides funding to dozens of people, largely on a part-time basis.

Keith and Keutsch also want an external advisory committee to review SCoPEx before it flies. The committee, which is still to be selected, will report to the dean of engineering and the vice-provost for research at Harvard. “We see this as part of a process to build broader support for research on this topic,” Keith says.

Keutsch is looking forward to having the guidance of an external group, and hopes that it can provide clarity on how tests such as his should proceed. “This is a much more politically challenging experiment than I had anticipated,” he says. “I was a little naive.”

SCoPEx faces technical challenges, too. It must spray particles of the right size: the team calculates that those with a diameter of about 0.5 micrometres should disperse and reflect sunlight well. The balloon must also be able to reverse its course in the thin air so that it can pass through its own wake. Assuming the team is able to find the calcium carbonate plume — and there is no guarantee that they can — SCoPEx needs instruments that can analyse the particles and, it is hoped, carry samples back to Earth.

“It’s going to be a hard experiment, and it may not work,” says David Fahey, an atmospheric scientist at the National Oceanic and Atmospheric Administration in Boulder, Colorado. In the hope that it will, Fahey’s team has provided SCoPEx with a lightweight instrument that can reliably measure the size and number of particles that are released. The balloon will also be equipped with a laser device that can monitor the plume from afar. Other equipment that could collect information on the level of moisture and ozone in the stratosphere could fly on the balloon as well.

Up to the stratosphere
Keutsch and Keith are still working out some of the technical details. Plans with one balloon company fell through, so they are now working with a second. And an independent team of engineers in California is working on options for the sprayer. To simplify things, the SCoPEx group plans to fly the balloon during the spring or autumn, when stratospheric winds shift direction and — for a brief period — calm down, which will make it easier to track the plume.

For all of these reasons, Keutsch characterizes the first flight as an engineering test, mainly intended to demonstrate that everything works as it should. The team is ready to spray calcium carbonate particles, but could instead use salt water to test the sprayer if the advisory committee objects.

Keith still thinks that sulfate aerosols might ultimately be the best choice for solar geoengineering, if only because there has been more research about their impact. He says that the possibility of sulfates enhancing ozone depletion should become less of a concern in the future, as efforts to restore the ozone layer through pollutant reductions continue. Nevertheless, his main hope is to establish an experimental programme in which scientists can explore different aspects of solar geoengineering.

There are a lot of outstanding questions. Some researchers have suggested that solar geoengineering could alter precipitation patterns and even lead to more droughts in some regions. Others warn that one of the possible benefits of solar geoengineering — maintaining crop yields by protecting them from heat stress — might not come to pass. In a study published in August, researchers found that yields of maize (corn), soya, rice and wheat3 fell after two volcanic eruptions, Mount Pinatubo in 1991 and El Chichón in Mexico in 1982, dimmed the skies. Such reductions could be enough to cancel out any potential gains in the future.

Keith says the science so far suggests that the benefits could well outweigh the potential negative consequences, particularly compared with a world in which warming goes unchecked. The commonly cited drawback is that shielding the Sun doesn’t affect emissions, so greenhouse-gas levels would continue to rise and the ocean would grow even more acidic. But he suggests that solar geoengineering could reduce the amount of carbon that would otherwise end up in the atmosphere, including by minimizing the loss of permafrost, promoting forest growth and reducing the need to cool buildings. In an as-yet-unpublished analysis of precipitation and temperature extremes using a high-resolution climate model, Keith and others found that nearly all regions of the world would benefit from a moderate solar geoengineering programme. “Despite all of the concerns, we can’t find any areas that would be definitely worse off,” he says. “If solar geoengineering is as good as what is shown in these models, it would be crazy not to take it seriously.”

There is still widespread uncertainty about the state of the science and the assumptions in the models — including the idea that humanity could come together to establish, maintain and then eventually dismantle a well-designed geoengineering programme while tackling the underlying problem of emissions. Still, prominent organizations, including the UK Royal Society and the US National Academies of Sciences, Engineering, and Medicine, have called for more research. In October, the academies launched a project that will attempt to provide a blueprint for such a programme.

Some organizations are already trying to promote discussions among policymakers and government officials at the international level. The Solar Radiation Management Governance Initiative is holding workshops across the global south, for instance. And Janos Pasztor, who handled climate issues under former UN secretary-general Ban Ki-moon, has been talking to high-level government officials around the world in his role as head of the Carnegie Climate Geoengineering Governance Initiative, a non-profit organization based in New York. “Governments need to engage in this discussion and to understand these issues,” Pasztor says. “They need to understand the risks — not just the risks of doing it, but also the risks of not understanding and not knowing.”

One concern is that governments might one day panic over the consequences of global warming and rush forward with a haphazard solar-geoengineering programme, a distinct possibility given that the costs are cheap enough that many countries, and perhaps even a few individuals, could probably afford to go it alone. These and other questions arose earlier this month in Quito, Ecuador, at the annual summit of the Montreal Protocol, which governs chemicals that damage the stratospheric ozone layer. Several countries called for a scientific assessment of the potential effects that solar geoengineering could have on the ozone layer, and on the stratosphere more broadly.

If the world gets serious about geoengineering, Fahey says that there are plenty of sophisticated experiments that researchers could do using satellites and high-flying aircraft. But for now, he says, SCoPEx will be valuable — if only because it pushes the conversation forward. “Not talking about geoengineering is the greatest mistake we can make right now.”

Nature 563, 613-615 (2018)

doi: 10.1038/d41586-018-07533-4

Users of prosthetic limbs could soon be able to feel sensation on them, thanks to an “electronic skin” (e-skin) invented by researchers from the National University of Singapore (NUS).

The artificial nervous system can detect touch more than 1,000 times faster than the human equivalent and is the first e-skin in the world to do so, according to Assistant Professor Benjamin Tee from the Department of Materials Science and Engineering at the NUS Faculty of Engineering, who led the research.

Previously, damaged e-skins would lose their function due to their interlinked wiring system.

But if a corner of the Asynchronous Coded Electronic Skin (Aces) nervous system tears, the rest of the skin continues to have sensation, just like human skin, the researchers said.

This is because the Aces detects signals like the human nervous system and it comprises a network of sensors – each working independently – connected via a single electrical conductor.

The research team, which took 11/2 years to develop the sensor system, published its innovation in Science Robotics journal today.

“When you lose a limb and get fitted with a prosthetic that doesn’t feel, it’s almost like you’re always feeling numb and cannot control things very well,” said Prof Tee. “If we have a skin that can make prosthetics smarter, we can restore motor functions, productivity and general quality of life for these people.”

In human skin, receptors send information about touch to the brain, which enables humans to intuitively sense touch.

When the Aces is attached to a prosthetic hand, a neural implant must be inserted into the patient’s arm so that the brain can detect the sense of touch from the e-skin.

The team will work with prosthetics researchers abroad to conduct a clinical trial of the e-skin with a patient using an artificial hand.

The Aces has also been designed for robots. “Robots need to have a sense of touch to interact better with humans, but robots today still cannot feel objects very well,” said Prof Tee.

For instance, a search-and-rescue robot digging through rubble will need sensation to know that it has to push away rocks and concrete to rescue a trapped person.

E-skin such as the Aces can be commercialised for robots within a year or two, Prof Tee said, but it will take five to 10 years for prosthetics that sense touch to reach patients, to allow for clinical trials.

by David Hambling

Everyone’s heart is different. Like the iris or fingerprint, our unique cardiac signature can be used as a way to tell us apart. Crucially, it can be done from a distance.

It’s that last point that has intrigued US Special Forces. Other long-range biometric techniques include gait analysis, which identifies someone by the way he or she walks. This method was supposedly used to identify an infamous ISIS terrorist before a drone strike. But gaits, like faces, are not necessarily distinctive. An individual’s cardiac signature is unique, though, and unlike faces or gait, it remains constant and cannot be altered or disguised.

Long-range detection
A new device, developed for the Pentagon after US Special Forces requested it, can identify people without seeing their face: instead it detects their unique cardiac signature with an infrared laser. While it works at 200 meters (219 yards), longer distances could be possible with a better laser. “I don’t want to say you could do it from space,” says Steward Remaly, of the Pentagon’s Combatting Terrorism Technical Support Office, “but longer ranges should be possible.”

Contact infrared sensors are often used to automatically record a patient’s pulse. They work by detecting the changes in reflection of infrared light caused by blood flow. By contrast, the new device, called Jetson, uses a technique known as laser vibrometry to detect the surface movement caused by the heartbeat. This works though typical clothing like a shirt and a jacket (though not thicker clothing such as a winter coat).

The most common way of carrying out remote biometric identification is by face recognition. But this needs good, frontal view of the face, which can be hard to obtain, especially from a drone. Face recognition may also be confused by beards, sunglasses, or headscarves.

Cardiac signatures are already used for security identification. The Canadian company Nymi has developed a wrist-worn pulse sensor as an alternative to fingerprint identification. The technology has been trialed by the Halifax building society in the UK.

Jetson extends this approach by adapting an off-the shelf device that is usually used to check vibration from a distance in structures such as wind turbines. For Jetson, a special gimbal was added so that an invisible, quarter-size laser spot could be kept on a target. It takes about 30 seconds to get a good return, so at present the device is only effective where the subject is sitting or standing.

Better than face recognition
Remaly’s team then developed algorithms capable of extracting a cardiac signature from the laser signals. He claims that Jetson can achieve over 95% accuracy under good conditions, and this might be further improved. In practice, it’s likely that Jetson would be used alongside facial recognition or other identification methods.

Wenyao Xu of the State University of New York at Buffalo has also developed a remote cardiac sensor, although it works only up to 20 meters away and uses radar. He believes the cardiac approach is far more robust than facial recognition. “Compared with face, cardiac biometrics are more stable and can reach more than 98% accuracy,” he says.

One glaring limitation is the need for a database of cardiac signatures, but even without this the system has its uses. For example, an insurgent seen in a group planting an IED could later be positively identified from a cardiac signature, even if the person’s name and face are unknown. Biometric data is also routinely collected by US armed forces in Iraq and Afghanistan, so cardiac data could be added to that library.

In the longer run, this technology could find many more uses, its developers believe. For example, a doctor could scan for arrythmias and other conditions remotely, or hospitals could monitor the condition of patients without having to wire them up to machines.