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Bionically Enhanced Chloroplasts Boost Photosynthesis and Spawn a New Field

Consider for a moment the magical work done by chloroplasts. These are the plant organelles that absorb light from the sun, convert it into chemical energy and ultimately use it as a building block for synthesizing glucose, the primary source of fuel for both plants and animals. While their achievement has the appearance of alchemy, like every other organelle, these chloroplasts are but little machines. Now, it seems they're due for an upgrade.

In a paper published yesterday in the journal Nature Materials, chemical engineers at the Massachusetts Institute of Technology report that when injected with single-walled carbon nanotubes (SWNTs), chloroplasts can be coaxed to photosynthesize more efficiently than normal.

The first phase of photosynthesis, referred to commonly as the "light reactions," involves excitation of pigments and the subsequent transport of electrons between multiple photosystems. The researchers used this flow of electrons as a measurement for the rate of photosynthesis and found that when the nanotubes were present the flow increased by 49 percent.

Chlorophyll, the pigment normally found in chloroplasts, can only absorb a small fraction of the light entering a plant, most of which resides in the 400 to 500-nanometer and 600 to 700-nanometer range. Although the researchers cannot yet offer an explanation for why carbon nanotubes would enhance the efficiency of chloroplasts, the team theorizes that it may be due to a broadening of this range. SWNTs are known to absorb light in the ultraviolet, visible, and near-infrared spectra.

The MIT engineers write:

"Improving photosynthetic efficiency may require extending the range of solar light absorption, particularly in the near-infrared spectral range, which is able to penetrate deeper into living organisms."

They report having the most success with chloroplasts that had been removed from the plant. Under these circumstances, they were able to inject the nanotubes directly into the organelle. 

In a separate experiment, the researchers sought to find a way to deliver nanotubes into a living plant. In order to do this, they developed a new technique called lipid exchange envelope penetration. Basically, they applied the nanotubes to underside of the leaf via a watery solution which is absorbed through tiny pores called stomata. The transfer across the fatty membrane of the chloroplast was made possible by coating the carbon nanotubes in negatively charged DNA.

When they introduced machinery into a living plant in this way, the chloroplasts received slightly less of a boost, photosynthesizing only 30 percent more efficiently than normal. But this delivery technique may itself be counted as a breakthrough.  

With it, the researchers have tried packing plant cells with particles that protect it from the damaging effects of light exposure, and with another type of carbon nanotube that has been shown to be sensitive to nitric oxide. With such techniques, chemical engineers may one day develop plants that function as pollution detectors. 

Indeed the researchers are arguing that their work establishes an entire new field of research, one they're calling plant nanobionics.

Malaysia Air Flight 370 Would Not Have Disappeared if We'd Had This System

A real-time flight-data recording method could have given investigators a far better idea of what has happened to Malaysian Airlines Flight 370, says Krishma Kavi, a professor of computer science and engineering at the University of North Texas, in Denton.

Kavi described such a system in detail iIEEE Spectrum in 2010, calling it the glass box, in contrast to the black box, which records flight data and voice data. The black box can be replayed only after the fact, and then only if it can be salvaged from an airliner's wreckage; the proposed glass box would immediately transmit the data to the cloud—the network of servers that increasingly blankets the earth.

"I strongly believe that our version of the black box (glass box) would have provided information indicating that all components of the plane were operating" in the wayward MH 370,  he said in an email yesterday. "It would have provided data on speed, altitude, direction of the flight... in real time."

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Soraa Aims for Better Light Quality with Gallium Nitride Tech

In the LED lighting industry, it’s an all-out race to lower costs and drive adoption. But LED company Soraa is betting that people will also purchase LEDs for the quality of light, as much as for efficiency and long life.

The Fremont, Calif.-based company said it intends to release a set of lamps later this year based on its third-generation LEDs, which use gallium nitride on a gallium nitride substrate. Soraa’s LED technology is different than most. The bulk of LEDs are made with GaN on a substrate of sapphire, while LED company Cree uses a silicon carbide substrate. A number of companies, including Bridgelux, are seeking to lower costs by manufacturing LEDs on larger silicon wafers.

Sapphire and silicon carbide substrates are less expensive and have mature production methods. By contrast, manufacturing on GaN substrates is far more challenging technically. Sorra was co-founded by LED pioneer, Professor Shuji Nakamura, in 2008 to commercialize GaN-on-GaN LEDs. The company began selling its first product, the MR16 lamp, in 2012. 

The advantage of having the same material for the active component and substrate is that there are fewer defects, so the LEDs can withstand high power, says Mike Krames, Soraa's chief technology officer. That translates into a relatively efficient conversion of current to light and good color rendering, he says.

Soraa makes LED lamps designed to replace halogen spot lights, which are often used in places where very good light quality is important, such as retail displays and museums. Light quality is measured by its color rendering index (CRI), or how accurately artificial lights display colors. Incandescent lamps, which include halogens, have a CRI of 100, and bulbs must have a CRI of 80 to meet the EnergyStar rating. Soraa’s lamps have a color rendering index (CRI) of 95.

In an effort to match the quality of halogen lights, Soraa starts with a violet LED and uses three phosphors to create a full spectrum of visible light, and thus a higher color rendering index, Krames says. Producing a wider spectrum of light requires more energy, but because it's an LED, its lights still have a big efficiency advantage over halogens with similar light quality, he says.

“Once people get more familiarity with their options, quality of light will be a bigger deal and a bigger driver of adoption than people believe,” Krames predicts.

Krames worries that consumers could be turned off by LEDs if manufacturers sacrifice light quality. Granted, Soraa’s entire business is centered on producing premium, high-CRI products so he has a clear bias. But light quality has not been the highest priority for LED manufacturers as they seek to replace other forms of lighting.

A report by the Department of Energy’s solid-state lighting program noted that LED prices have dropped dramatically and efficiency has improved over the past four years, but the quality has remained about the same. The majority of the bulbs surveyed by the DOE have a CRI between 80 and 85, which is the typical rating for compact fluorescent lamps.

Instead, LED lighting companies have focused on bringing down price—something they've been successful at. When Philips started selling a 60-watt equivalent LED bulb with omnidirectional light in 2010, it cost almost $40. Last week, Cree cut prices by 23 percent so that a 60-watt equivalent now costs under $10. It also introduced a 100-watt equivalent priced under $20.

Cree designed its bulbs with a vertical “tower” that gives off light from the center of the bulb to mimic the way an incandescent bulb glows. The CRI of its products are about 83, which is good enough for the majority of uses, says Mike Watson, the vice president of product strategy at Cree. “What we really care most about is what consumers see. Having done many demonstrations for consumers in stores, I’m stunned at the number of people who think an LED at 83 CRI is better than an incandescent at 100,” he says.  

New lighting labels require manufacturers to indicate CRI, which could draw more consumer attention to light quality. In addition, California put in place a voluntary specification for LEDs that sets a minimum of 90 CRI. The standard was put in place to avoid a flood of low-quality LEDs, which occurred when compact fluorescent bulbs were introduced, souring many consumers’ opinions on efficient lighting.

Higher quality light does mean a more expensive product, but Krames says there's potential to improve the economics of GaN-on-GaN LEDs. Soraa's third-generation LEDs improve energy efficiency by 30 percent and, since GaN-on-GaN is relatively new, there’s more room for improvement than existing technologies, Krames says.

Premium, high-CRI bulbs are now mainly used by commercial customers, but perhaps consumers will eventually buy in, too. “Once people start to get a taste for higher CRI lamps, they’re not going to want to go back,” says Krames. 

Why There's No Real Cyberwar in the Ukraine Conflict

Warnings of a cyberwar between Ukraine and Russia over the recent Crimean crisis have been greatly exaggerated. From the start, Russia seems to have relied upon traditional military force and a barrage of old-fashioned "information war" propaganda in its swift takeover of Crimea. Whatever cyber attacks that have occurred so far probably represent the work of Russian or Ukrainian "hacktivists" rather than strategic military strikes, experts say.

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Teaching Cars To Feel Your Pain

Now we drive our cars; in the future, they'll drive us. In between, though, the division of labor will get a little murky, and there could be an unfortunate failure to communicate. Our cars will just have to learn to read us better.

The car that can see a driver's emotional state written on his face could anticipate a bout of road rage and head it off. It could offer advice, or it could just humor the poor, carbon-based life-form. "Yes, that fellow in the red sports car really was rather thoughtless," the car might say, sympathetically. "They really shouldn't let people—I mean, people like himon the road, should they?"

The facial-recognition part of that scheme is under investigation at the Signals Processing Laboratory of the École Polytechique Fédéral, in Lausanne, Switzerland. Researchers trained the system on photos to identify anger or the closely related emotion disgust, then validated the system by testing it on videos, including many taken inside a moving car (provided by the French auto maker Peugeot Citroën, a collaborator in this research).

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California's Dreamin' About Autonomous Car Regulations

Tuesday's public hearing on the regulation of robocars shows that California's Department of Motor Vehicles is sticking to a state mandate to produce a law by year's end. That would make it the first state to accommodate the routine use of autonomous vehicles. (Nevada was the first to approve their use for research purposes.)

The regulators' job is harder than it looks. "The life of the law has not been logic; it has been experience," argued jurist Oliver Wendell Holmes, Jr., long ago. California's regulators must rely on logic alone.

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NASA Needs Coders to Help Prevent Asteroid Armageddon

Savvy coders can soon help NASA defend Earth against asteroid threats and win some cash prizes in the bargain. The U.S. space agency has joined forces with an asteroid-mining company to recruit programmers who can help identify asteroids in the slew of images taken by ground-based telescopes.

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Flock of 104 Spacecraft Set for Launch

(Update, 14 March: The launch of the SpaceX rocket that will carry KickSat to space has been postponed until 30 March at the earliest.)

In a few weeks time, a fleet of 104 spacecraft the size of small cheese crackers should be released into space.

This will be the first free-flying test of what could be a new approach to space exploration, one that aims to use bare integrated circuits as spacecraft. Since chips are small and easy to mass produce, it might be possible to launch them by the thousands for use as distributed sensors to monitor space weather, measure the ionosphere, or explore other planets. As Cornell University professor and former NASA Chief Technology Officer Mason Peck described in a 2011 feature for IEEE Spectrum, tiny chip-based spacecraft might ultimately be able to fall gently onto Martian plains without a parachute or coast around for weeks in Titan’s thick atmosphere.

For this mission, each spacecraft in the small armada has a mass of just 5 grams and fits its solar panels, logic, communications gear, and sensors on a single square circuit board measuring 3.5 cm on each side. “They’re way smaller than anything else that’s flown in space—on purpose at least,” says organizer Zac Manchester of Cornell University.

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Electrical Stimulator to Prevent Migraines Receives FDA Approval

Pharmaceuticals are so 20th century. Medicine's buzzy new trend is electroceuticals: ways to treat ailments with electricity rather than chemicals. Yesterday, the U.S. Food and Drug Administration approved a new entry into this field, when it gave the nod to a device that prevents migraines by electrically stimulating nerves in the cranium. The device is manufactured by the Belgian company STX-Med, and is already approved for commercial sales in Europe, Canada, and Australia.  

Cefaly, a battery-powered device that resembles a tiara or a headband, can be used for daily 20-minute sessions. The FDA says this treatment may help migraine patients who can't tolerate or don't respond to medication.

The device works by stimulating the trigeminal nerve, the largest cranial nerve, which carries sensory information from the face to the brain, and which has also been associated with the pain of migraine headaches. According to the Cefaly website, its mechanism is based on the gate control theory of pain. By providing sensory input to the nerves, the device essentially keeps a neural gate closed to pain input. This theory explains why you rub your elbow after banging it—the sensory stimulus overrides the pain stimulus, which is transmitted to the brain on different nerve fibers. 

The FDA's approval is based on several studies conducted in Europe. One study of 67 migraine patients, published last month in Neurology, found that Cefaly users experienced significantly fewer migraines over the course of a month than patients who used a placebo device. However, in a user satisfaction survey, only 54 percent of patients who rented a trial device said they wanted to purchase the device. As those users who returned the Cefaly were shown to have used the device for only about half the recommended time, it seems possible that migraine patients are still more comfortable with popping a pill than wearing a tiara around the house.  

The product video provides more information, although there's a good bit of jargon to deal with. It may help to know that nociceptors are the receptors on neurons that respond to a pain stimulus. 

Image and video: Cefaly

“Naked Truths” About Wearable Electronics

So, maybe you’ve bought a Nike+ Fuelband or a Jawbone UP band. Maybe it’s still on your wrist, and you check its data compulsively. But maybe it’s in a drawer, with your clunky smartwatch, your portable HD radio, and your Microsoft Zune.

Or maybe you are an early adherent of Google Glass, stoically enduring the discomfort and occasional aggression of friends, relatives, passersby, and drunk, enraged bar patrons. On the other hand, perhaps, like app developer Q Manning, you’ve concluded sadly that Google Glass is “great for texting and that’s about it.”

“I don’t think wearable technology has found its niche,” Manning added during a panel session Monday at the SXSW Interactive conference. “We all know we want it, but we don’t know what we want it to do yet. We’re all waiting for someone to solve that problem, but, unfortunately, Steve [Jobs] is gone.”

Manning’s co-panelists certainly had a few ideas, though, and one of them was vividly demonstrated by a pair of statuesque models who took the stage in technologically advanced and yet attractive underwear, prompting a blizzard of camera flashes. The demonstration came as close as could be reasonably expected to fulfilling the promise of the session’s title: “Tech Off Your Clothes: Naked Truths Of Wearables.”

The underwear were prototypes developed in a project called “Fundawear,” explained panelist Jay Morgan of the marketing firm Havas Worldwide. Havas had been hired by the UK-based manufacturer Durex, which was eager to associate its brand more with innovation. Though it offers an extensive line of personal massagers, for example, Durex is generally recognized only as a maker of condoms.

Havas was charged with coming up with a splashy innovation for Durex, and their brainstorming soon centered on the question, “can we do something for [lovers] when they are not together? Can you actually touch someone over the Internet?”

This proposal led to what can only be called a milestone in human civilization: the first ever electrically-engineered underwear. Fundawear was designed by another of the SXSW panelists, Billie Whitehouse, whose firm is called Wearable Experiments. The prototype Fundawear samples are close-fitting black undergarments equipped with tiny haptic electromagnetic vibrators, which produce a momentary sensation much like piezoelectric-based units used to create the quick vibration in a smartphone when a key is touched. The units are strategically installed in the garments—in the female version, in both brassiere and panties—to make contact with sensitive regions of the body. When the wearer’s partner touches his or her smartphone—the sensitive regions are helpfully indicated on a template on the phone’s screen—the wearer feels a gentle frisson, or even a light stroke, depending on whether the partner has touched or swiped the screen.

The engineering challenges were nontrivial, Morgan explained. First, they wanted to create the sensation of a lover’s gentle touch, and finding a technology that could reliably and safely produce that feeling—and be laundered—wasn’t easy. “There was some great work in electroactive polymers at the University of Auckland,” Morgan explained. “We contacted them and they said, ‘where are you going to stick this stuff?’ And we said, ‘down in your pants.’ They said, ‘Oh, that’s probably not a good idea,’” noting that the polymers operate at 4500 volts.

Another challenge was making instantaneous contact, no matter how far apart the partners were. An app pairs the wearer’s smartphone to his or her garment, using WiFi (Bluetooth would be used if Fundawear is put into production, Morgan said). But the users’ phones have to communicate with each other securely and instantaneously. The design team solved that one by using Amazon Web Services, a cloud scheme, to convey the data between phones. Each partner has a secret key to assure security, Morgan added.

Eugenia and Stephen, the models who wore Fundawear at the SXSW session, were delighted with it. “It’s a very light vibration, like a touch,” said Eugenia. “It depends on how you touch,” she said. “If you slide, it’s like a stroke.” The two did not know each other prior to the SXSW assignment, and they each controlled their own undergarment, Eugenia said. “We didn’t want to be too intimate in this situation,” she explained. (Stephen didn’t have a comment.)

Morgan said executives with Durex’s Global Product Development Team are studying the feasibility of putting the wearables into production. He said a decision could be announced in the next several months.

Wearable Experiments’ Whitehouse demonstrated another possible direction for wearables at the session. She was wearing her Navigate Jacket, which pairs to a smartphone app and gives gentle and appropriately timed taps on the left or right shoulder to guide the wearer to a destination.

Asked about the future of the jacket, Whitehouse replied, possibly with tongue slightly in cheek, “The future of this jacket, for me, is inductive-charging coathangers.”

Later in the session, when asked about what people, particularly older people, really want in wearable electronics, she said: “My mother, in particular, just wants a device that repels all other technology. That doesn’t let people track her, or contact her.”

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