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Feds Probe Cybersecurity Dangers in Medical Devices

When person’s survival is reliant upon medical implants and other devices with computer chips, the potential consequences of cybersecurity flaws can be deadly. The U.S. Department of Homeland Security is now looking into at least two dozen cases of possible cybersecurity flaws in medical devices ranging from artificial heart implants to hospital infusion pumps.

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See-Through Sensors for Better Brain Implants

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Brain scientists first discovered how to use light to remotely control genetically-modified brain cells about a decade agoa breakthrough that has enabled new scientific studies of depression, addiction and Parkinson’s disease. Now a new generation of transparent brain sensors could record brain cell responses without blocking the light’s access to the underlying brain tissue.

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Nobelist's New Microscope Captures Life in Action

In December Eric Betzig is expected to fly to Stockholm to receive his share of the 2014 Nobel Prize in Chemistry for expanding the frontiers of microscopy. It seems he just couldn’t leave those frontiers alone. 

In a tour de force paper in Science, Betzig and his collaborators have introduced a new method for imaging biological processes with unprecedented resolution in space and time.  Betzig and Bi-Chang Chen, Wesley R. Legant, and Kai Wang from his lab at the Howard Hughes Medical Institute’s Janelia Research Campus were joined by collaborators from 14 other groups around the world to come up with the new microscopy method.

The technique, called lattice light-sheet microscopy, generates extraordinarily sharp, 3-D images and videos of live organisms at scales ranging from single molecules to early-stage embryos. It builds on other methods Betzig has pioneered. 

One of those methods was something  the Nobel Prize committee mentioned in making their award, Betzig’s development of photoactivated localization microscopy (PALM). PALM lets researchers see objects smaller than the half-wavelength diffraction limit—by shining less light on the subject, rather than more.

The diffraction limit is the light microscopist’s nemesis. Violet light has the shortest wavelengths most humans can see, down to about 380 nanometers (though some people who have lost their corneas to cataract surgery can see into the ultraviolet, to perhaps 300 nanometers). Thus, objects smaller than about 200 nanometers are invisible to conventional light microscopy. In PALM, Betzig linked fluorescent molecules to proteins in the feature he wanted to study, and then shined a light to stimulate them. The labeled molecules responded weakly, with only a small, widely separated percentage of the fluorescent molecules emitting a few photons. When the emitting molecules were farther than 200 nm apart, each produced a single, highly localized bright spot on the image. Betzig then stimulated and imaged the sample over and over again, hundreds of times, to build a mosaic of sub-200 nm detail.

The new lattice light-sheet technique is also based on a Bessel beams method the Janelia group introduced in 2011. Bessel beams are nondiffracting wave patterns, vanishingly-thin rings of light produced by shining a laser through an annular mask. These beams keep their shape, and don’t spread out as they propagate, allowing researchers to generate extremely thin sheets of light.

In their new paper, Betzig’s team says that they have “crafted ultrathin light sheets.” Crafted is the right word: they shape the light the way a carpenter turns, shaves, and carves a baulk of lumber into a graceful table leg.

First, the laser beam is squeezed and stretched into a thin vertical line. Then it is bounced off a spatial light modulator (SLM)—an ultra-fast LCD that flashes a series of black-and-white patterns that reflect the incoming stripe of laser light back in a defined lattice of high and low intensity. (The SLM is the main feature distinguishing the lattice sheet method from its Bessel beam predecessor.) The reflected pattern passes through a thin transform lens, which throws a Fourier transform of the pattern onto the annular Bessel beam mask. The light then bounces between galvanometer-controlled mirrors that determine where the nodes of the lattice will fall in the light sheet. Only then does the beam pass through a lens to be focused into the sample, producing a hexagonal pattern of illuminated dots that spread in a sheet right and left of the beam. If the pattern is chosen wisely, interference effects actually sharpen the definition of the points, increasing resolution.

A piezoelectric stage moves the sample incrementally through the light sheet, which activates fluorescent markers in an ultrathin slice of the sample.

The lattice light-sheet device works in two modes—structured illumination microscopy (SIM) for high spatial resolution and “dithered” for better time resolution. SIM can resolve features in the 150-280 nm range. In the high-speed dithering mode, the lattice is swept across the sheet faster than the camera’s exposure time, illuminating a whole slice in a single step to reduce the number of steps necessary to photograph an entire volume. Dithered mode functions at 100 frames per second—about 7.5 times faster than SIM mode but, at  at 230-370 nm, it only has two-thirds SIM’s resolution.

No matter how kindly intended, a flood of photons pouring into a cell can injure or kill it—especially if it is dividing or otherwise vulnerable. The lattice light-sheet technique doesn’t do that. “The chief benefit of lattice light-sheet excitation… is its exceptionally low photobleaching and phototoxicity,” the researchers write. Each of the examples presented in the paper “was distilled from tens or hundreds of thousands of raw 2-D images,”  a figure one or even two magnitudes higher than the number of exposures allowable with other light methods.

The research produced remarkable images from a large collection of experiments conducted in collaboration with colleagues from 14 other groups around the world. Here are just a few of them:

  • Repeatedly imaging a non-living fixed sample to localize 4.2 million individual proteins in the nucleus’ membrane to within 8 to 45 nm.
  • Tracking single molecules of the protein that marks the ends of growing microtubules, the fibers that latch onto and reposition the replicating chromosomes during cell division, to build a comprehensive dynamic map of their growth [image above]. 
  • Keeping the light sheet stationary to follow extremely rapid changes in a protozoan at more than 300 frames per second, including stop-action images of moving cilia that could allow biologists to calculate the force each of the tiny tails generates.
  • Filming details of key stages in the development of live fruit fly embryos in unprecedented detail.

The researchers have patented the lattice light-sheet microscopy system. They’ve licensed it to microscope maker Zeiss and will also share the detailed instructions to researchers who wish to build their own instruments.

Where many scientific abstracts close with a guarded boast about future potential, this one ends:  “The results provide a visceral reminder of the beauty and complexity of living systems.”

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Rapid muscle contractions in a C. elegans embryo in the three-fold stage, with labeled GFP-PH domains (green) and mCherry-histones (magenta), as recorded in a single 2D optical section at 50 frames/sec. Scale bar, 10 um. (Video: Betzig Lab/HHMI)
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Samsung Demos Multi-Gbps Speeds Using 60 GHz Wi-Fi

Samsung has announced that it plans to bring a new multi-gigabit-per-second wireless technology to consumer devices as soon as next year. The technology is an implementation of the IEEE 802.11ad standard, operating in the 60 gigahertz frequency band. The company said the technology supports data transmission rates of up to 4.6 Gigabits per second, or about five times as fast as current Wi-Fi systems. 

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XPrize Announces Finalists Building Next-Gen Medical Sensors

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Today’s home medicine kit is fairly limited when it comes to diagnostics: You can take your temperature, check your blood pressure, and give yourself a home pregnancy test, but that’s about it. The Nokia Sensing XChallenge (from the XPrize folks) aims to improve that situation by spurring inventors to create portable gadgets that consumers can use to collect accurate, real-time health information. The 11 finalist teams, announced today, are building gadgets that do lab tests, monitor heart disease, check vital signs, and more. 

The Sensing XChallenge is distinct from a very similar competition, the Qualcomm Tricorder XPrize, in which teams are vying to create a universal diagnostic tool along the lines of the handheld tool wielded by Star Trek’s Dr. McCoy. In the Tricorder contest, the devices are required to diagnose a specific list of 15 ailments, whereas in the sensing challenge the tools can be designed to do just about anything.   

However, the XPrize doesn’t see redundancy here, but rather a symbiotic relationship, says Grant Campany, senior director of the sensing challenge. The Nokia contest is intended to reward teams for developing technologies that could be incorporated into a Tricorder device, he told IEEE Spectrum in an email. Several sensing teams are validating technologies for collaborating Tricorder teams, Campany says, which are racing to build at least 30 working Tricorder devices for consumer testing next year.

The Nokia contest’s judges will have some apples vs. oranges decisions to make, because the 11 finalists’ gadgets are designed for a wide variety of applications. How do you compare a handheld spectrometer, which can detect biomarkers of liver function in a drop of blood, to a pressure sensor implanted in the pulmonary artery of a heart disease patient? Other devices include a wearable sensor to detect sleep apnea, a mobile phone-based imaging app to find symptoms of eye disease, and a variety of mobile lab gadgets. Which among these is the most meritorious, and therefore worthy of the $525,000 grand prize? 

Campany says the judges have a list of criteria that include technical innovation, reliability, ease of use, and relevance to a public health need. He also notes that crowd voting accounts for 10 percent of the teams’ scores; you can cast your vote for the winner through the end of the month. The winning team will be announced in November at the Exponential Medicine conference. 

4-D Printing Turns Carbon Fiber, Wood Into Shapeshifting Programmable Materials

Just as 3-D printers create objects that have three-dimensional characteristics, 4-D printers create objects that have four-dimensional characteristics, in that they include a dynamic component that causes their structure to change over time—relying on water, heat, or light to activate them.

Using a multi-material printer, it’s possible to generate objects with these properties all in one go. Such “programmable materials” may one day mean that you can buy flat-pack furniture at Ikea, take it home, and hit it with a garden hose while you watch it slowly assemble itself. We don’t even have to speculate: MIT is working on this exact thing.

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Mars Comet Shames Earth Dithering

Comet siding Spring will make a spectacular fly-past of the planet Mars on 20 October. Among the observers will be seven robotic space probes sent from Earth.

Only discovered less than two years ago, the newborn comet, fresh from the Oort Cloud nursery far beyond Pluto, probably carries secrets of the origins of the solar system. Its arrival was so sudden and unexpected that no Earthborn probe could have been built and launched in time to intercept it. Instead, by the most freakish of improbabilities, it fell directly into range of a space fleet that had assembled for an entirely different reason.

On Sunday the comet is to flash through the Mars-and-moonlets system, travelling south-to-north nearly perpendicular to their orbital plane. It’ll miss Phobos and Deimos by 112,000 kilometers, and skate by Mars by about the same. When its potentially dangerous dust trail follows, four of the five orbiting probes will be snuggling safely behind the planet's bulk. The two surface rovers will be protected by the Martian atmosphere. The aged Opportunity will look for the comet in pre-dawn twilight, and the more-recently-arrived Curiosity, on the opposite side of the planet, will be in evening twilight.

Besides carrying cosmic secrets, the comet is also carrying a question. Why aren’t there people out there front-row-center for what might have been the greatest solar system spectacle of all human history? Where are the human eyeballs and human souls that should have been rising from the Martian surface at this marvel. The sight would likely have been a literally astronomical reward for the boldness and ingenuity that had placed humans there?

Fifty years ago, during the hey-day of the Apollo Program development, the issue of human flight to Mars wasn’t even open to doubt or debate – the only issue was the time frame. Could it be done within 20 years of a moon landing, as optimists hoped? Or would it take 30, or 40, as the realists expected?

True, these visions rested on the wispy foundations of imaginary engineering breakthroughs and in blissful ignorance of the real challenges of long-term space operations and human physiology. The maturity of the independently-developed technologies that when harnessed together in the 1960s enabled— barely enabled—brief lunar surface sorties by astronauts also misled futurists into thinking a new crop of advanced engineering capabilities could easily be mustered.

In hindsight, sophisticated reliability assessments, which properly assessed Apollo mission success at 80 percent and crew survival at 95 percent, when applied to even the best humans-to-Mars strategies, gave the likelihood of success at  less than5 percent and of crew survival as less than 50 percent. We didn’t even know how much we didn’t know.

But was that really an excuse for not even seriously trying? It’s not as if we couldn’t have afforded it. Did not trying to get humans to Mars really saved the world’s governments any serious money?

So instead of on-site living eyewitnesses to this spectacle, we’ve sent R2D2, and been lucky at that. The robots will perform just fine, and it will still be an amazing event. Yet it can also serve as a slap-in-the-face reminder that just as on Earth, “fortune favors the bold”. It would have vastly increased human culture if bold humans now on Mars— and the bold societies that might have existed to send them— would be justifiably exulting in this unexpected reward from the inanimate Universe, seen first-hand instead of through robot eyes.

There are more glorious surprises in the infinite “Out There”, waiting to be stumbled across and recognized. Let’s not be caught flat-footed like this again.

The opinions expressed are those of the author, not IEEE Spectrum, the IEEE, or its organizational units.

Google Funds New Brazil – U.S. Undersea Fiber Optic Cable

This week, Google announced its investment in a new undersea fiber optic cable connecting the United States and Brazil that will help ensure that its services continue to run smoothly in South America.

 The $60 million project, which will be capable of carrying up to 64 terabits of data per second, is scheduled to be completed by the end of 2016. It also marks Google’s second investment in continent-connecting cables this year.

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Will Humans Start Colonizing Mars in Ten Years?

Colonizing Mars has long represented one of the more ambitious dreams for space travel proponents ranging from NASA scientists to Silicon Valley entrepreneur and SpaceX founder Elon Musk. The latter also envisions sending humans to Mars sometimes in the next several decades, and has mused about how to build a Mars colony population of 1 million people in an Aeon interview.

Mars One — a nonprofit organization based in the Netherlands — shares some of the Musk’s goals and indeed, the Mars One vision relies on Musk’s SpaceX’s Falcon Heavy rocket. But Mars One’s concept of seeding Mars with human colonies by launching one-way missions recently received some close scrutiny from a team of MIT researchers.

The MIT team’s critique identified potential challenges and estimated that settling the first batch of Mars colonists would require about 15 launches of the Falcon Heavy rocket being developed by Musk’s firm SpaceX at a cost of $4.5 billion. MIT also suggested that Mars One may want to dial back its aggressive schedule of sending four-person crews every 26 months starting in 2024.

The MIT paper took a particularly close look at the Mars One idea that it could establish a sustainable colony on Mars using existing technology starting in the 2020s, according to Space Policy Online. MIT’s researchers concluded that Mars One was overreaching with its statement that “no new major developments or inventions are needed” to make such an effort possible. In a Reddit AMA, they also urged Mars One to take a slower-paced approach that field-tested all the necessary habitat equipment on the red planet before sending humans.

“We believe this is a time for boldness in space exploration, but there is also a necessary amount of caution,” said MIT’s team, a group overseen by Olivier de Weck, an aeronautics and astronautics engineer at MIT. “A catastrophe in the early days of Martian colonization may cripple the endeavor in today’s risk-averse society.”

In 2012, Mars One first proposed sending Mars settlers on a one-way trip to the red planet starting in 2024 — a project based on the idea of making such a Mars endeavor into a multimedia reality show. Mars One also envisions first sending robotic missions to set up the crew habitat between 2018 and 2023, before the first humans ever set foot on the red planet.

MIT’s simulation of the Mars One mission plan highlighted a few areas in particular.

First, the study found that the cost of the permanent colony would grow steadily over time because of the increasing requirement for spare partsspares would account for an estimated 62 percent of mass transported to Mars after almost 11 years of settlement.

Second, the study identified a potential problem of managing excessive oxygen levels if the Mars One effort grew all its food as crops on the red planet.

Third, it pointed out that carrying all food from Earth could be more efficient than growing Mars crops because of Martian agriculture’s equipment requirement.

The MIT paper presented at the International Astronautical Congress (IAC2014) in Toronto has sparked a firestorm of online debate between supports of the Mars One vision and the more skeptical side of the space enthusiast community. But the MIT team clarified during the Reddit AMA that it did not set out to “discredit” Mars One and simply wanted to clarify the technology road map required for such an effort. (MIT team leader Olivier de Weck talked Mars mission logistics in IEEE Spectrum’s 2009 special report on going to Mars.)

Suggestions from the MIT team during the Reddit AMA session included testing all life support and in situ resource utilization (ISRU) technologies on Mars for at least 26 months before sending humans. The researchers also pointed out that slowing down the rate of sending settlers could reduce the impact of the increasing spares requirement on mission mass. They also raised the future possibility of 3-D printing and other ISRU technologies reducing the need for spares.


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