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The Slightly Bizarre Fantasies of the 2015 Electrolux Design Lab Challenge

Every year, Electrolux asks design students to stretch their already alarmingly flexible imaginations and develop concepts around a theme that's intended to “raise questions about what design will be like in the future.” This year's theme is “Healthy Happy Kids.” And as per usual, the concepts the students dreamed up are mostly (or entirely) unconstrained by things that are often inconvenient to designers, like the laws of physics. Let's take a look at the top six finalists to see how reality will inevitably fail to live up to the future of design.

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Bummer: No Evidence That Anti-Depression Apps Really Work

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England’s publicly funded health care system, the National Health Service (NHS), has endorsed more than a dozen depression treatment apps, but there’s no proof that most of them actually work, according to a report published this week in the journal Evidence Based Mental Health. The authors of the report examined each of the fourteen depression apps the NHS lists in its app library and found that only two of them had been clinically validated using standard  metrics. 

Depression apps are computer-based programs that help people monitor their symptoms, provide education, and sometimes offer coping skills and therapy. But many of the NHS-endorsed apps “seemed a bit sketchy” or made strange recommendations, says Simon Leigh, an author of the paper and a senior health economist at Lifecode Solutions in Liverpool, UK. “I think it was rather dangerous of the NHS to endorse them without having the information.” 

Leigh’s study is the latest in a slew of reports finding that mental health apps generally lack rigorous testing. Recent research papers on apps that treat bipolar disorder, eating disorders and post-traumatic stress disorder (PTSD) found a similar dearth of evidence validating app developers’ claims. 

“Mobile health apps are increasing at an amazing rate, and most don’t have any empirical validation,” says Stephen Schueller, a clinical psychologist at Northwestern University who specializes in internet and mobile interventions for depression, and was not involved in the NHS study. “The last time I looked at the literature, there were five or six randomized controlled trials of an app for depression, and none of those apps were available on a public app store, and none ran on an iPhone or Android operating system. So anything that I would want to touch as a consumer has not been validated in a randomized controlled trial”—the gold standard of clinical research, he says. 

The gap between consumer health technology and science to support it is nothing new, of course. Computerized systems that help physicians make clinical decisions fail two-thirds of the time, according to a paper published in June. And a report published last month by IMS Institute for Healthcare Informatics found that more than 165,000 mobile health apps are now available to consumers—twice as many as two years ago—severely outpacing the mechanisms by which physicians can assess them. Fifty percent of them have “limited functionality,” according to the report. 

The fact that thousands of mental health apps may be bunk may not come as a surprise to many consumers. The trouble comes when an influential national health system like NHS puts its stamp of approval on an app without requiring standard mental health tests to be applied to it, says Leigh. Metrics the NHS commonly uses to accredit other mental health treatments include the Generalized Anxiety Disorder 7 (GAD-7) and the Patient Health Questionnaire-9 (PHQ-9). Only two of the apps listed on the NHS library—Big White Wall and Moodscope—used such metrics, Leigh’s study found.

The potential harm of a depression app that doesn’t work is that it could compound feelings of anxiety and lack of motivation. “I’m untreatable. I’m a failure. These are common symptoms of depression,” says Schueller. “Lack of motivation is another big one, so if a person gets motivated enough to download an app, and then it doesn’t work, we might have missed that window and they might not get motivated again,” he says. “But I’m not terribly worried that these apps might actually cause problems for a person,” he says.  

NHS does not claim to have officially accredited the apps in its library, but “their badge is plastered all over them,” says Leigh. “And the NHS badge connotes an implicit level of quality.” The NHS says it chooses apps based on three criteria: that the apps are relevant to people in England, that they use information from a trusted source, and that they comply with legislation on appropriate use of data.

The NHS did not return Spectrum’s request for comment by press time. The agency has noted on its website that its health app library, which began in 2013, was a pilot project, and is scheduled to close this week. A new list of online mental health services has appeared on the NHS Choices website.

Other reports have criticized the NHS apps library as well. Imperial College London last month published a studying finding that many of the agency’s endorsed apps sent unencrypted personal and medical details over the internet.  

The US Food and Drug Administration (FDA) so far hasn’t taken much of an active stance on validating mental health apps. The agency published guidance in February this year, noting that apps that are intended to help with coping skills for people with depression and other psychiatric conditions may be subject to FDA oversight. One developer of cognitive health software, Akili Brain Interactive, plans to approach the FDA for approval of its therapeutic video games. The FDA in 2010 approved the first prescription-only diabetes app, called BlueStar

A Particle Accelerator the Size of a Sewing Needle

An international research team has demonstrated a high-performance particle accelerator the size of a 1-millimeter mechanical pencil replacement lead.

Tens of thousands of particle accelerators around the world are used for more than physics research. They are also used to manufacture semiconductors, probe new materials, illuminate too-fast-to-follow chemical reactions, treat cancer, strengthen polymers, sterilize medical devices, and even to make diamonds green and pearls black.

A key accelerator parameter is the acceleration gradient, the energy (measured in mega electron volts, MeV) gained per meter of travel. The amount of energy the accelerator can pump into a cluster of particles, electrons, for example, thus becomes a function of the device’s gradient and length. And cost, of course, increases with physical size of the accelerator.

Thus, conventional linear accelerators, with acceleration gradients around 30–50 MeV/m, can grow as big as the 3,073-meter-long Stanford Linear Accelerator in Menlo Park, Calif., housed in what may be the world’s longest building. These machines accelerate charged particles using either a pulse of radio frequency radiation or a wakefield (using high energy “bunches” of electrons to blast a tunnel through plasma; when the tunnel collapses back on itself, following particles accelerate by riding the charged wake of the collapsing front). RF accelerators can reach energies of a few tens of mega electron volts before the RF energy itself begins to destabilize the mechanism in what’s called plasma breakdown. In wakefield approaches, balancing the skittish plasma bubble requires terawatt or petawatt lasers, tricky micromachinging, and femtosecond laser timing.

In Nature Communications, researchers describe an alternative: a compact device that uses pulses of terahertz (THz) radiation. The research group includes scientists from the Massachusetts Institute of Technology (MIT), the University of Toronto, and the Deutsches Electronen Synchrotron (DESY, the German Electron Syncrotron), the Center for Free-Electron Laser Science (CFEL), the Max Planck Institute for Structure and Dynamics, and the University of Hamburg (all in Hamburg, Germany). It was led by Franz Kärtner, who is affiliated with MIT, CFEL, and DESY.

“Terahertz frequencies provide the best of both worlds,” the group writes. “On one hand, the wavelength is long enough that we can fabricate waveguides with conventional machining techniques, provide accurate timing, and accommodate a significant amount of charge per bunch [of electrons]… On the other hand, the frequency is high enough that the plasma breakdown threshold for surface electric fields increases….”

The terahertz approach also allows them to use readily available picoseconds lasers.

The accelerator itself is a quartz capillary about 1.5 centimeters long and 940 micrometers in diameter, sheathed in a copper jacket. The quartz walls are 270 μm thick, leaving a central vacuum 400 μm in diameter.

In operation, a 0.45 THz pulse is radially polarized bounced off a mirror to enter at one end (call it the right end) of quartz tube. As the pulse traveled down the tube, electrons are injected at 60 keV through a pinhole at the left end. When the terahertz pulse reflects off the left wall (around the injection pinhole) it catches the electrons, accelerating them back towards the right.

In the initial experiments, the electrons could ride the wave for just 3 mm before the wave started to spread out. That short ride, however, boosted their energy to 67 keV. A back of the envelope calculation translates this modest energy gain into an acceleration gradient over 2 MeV/m.

“This is not a particularly large acceleration, but the experiment demonstrates that the principle does work in practice,” explains co-author Arya Fallahi of CFEL. “The theory indicates that we should be able to achieve an accelerating gradient of up to one gigavolt per meter.”

Or, as the paper itself concludes, “This proof-of-principle terahertz linear accelerator demonstrates the potential for an all-optical acceleration scheme that can be readily integrated into small-scale laboratories providing users with electron beams that will enable new experiments in ultrafast electron diffraction and X-ray production.”

MIT's 3-D Microwave Camera Can See Through Walls

Visible light is all well and good for things like eyeballs, but here at IEEE, we do our best to cover the entire spectrum. As always, we’re especially interested in anything that confers superhero-like abilities, like X-ray vision, or in this case, M-wave vision, which sounds even more futuristic. At MIT, they’ve been working on a prototype for a time of flight microwave camera which can be used to image objects through walls, in 3-D.

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Immigrants Have a Growing Role in the U.S. Sci-Tech Workforce

Immigrants have a growing presence in the U.S. science and engineering workforce, according to a new report by the National Science Foundation. Between 2003 and 2013, the number of U.S. scientists and engineers increased from 21.6 million to 29 million. In that time, the number of immigrants in the field rose from 16 percent of the total tech workforce (3.4 million) to 18 percent (5.2 million).

The percentage of foreign-born scientists and engineers who were employed in 2013 was about 81 percent—the same as their U.S.-born counterparts.

According to the report, 57 percent of immigrant scientists and engineers hail from Asia; this group includes naturalized citizens, permanent residents, and temporary visa holders. Immigrants from the Americas and the Caribbean make up 20 percent, and Europeans make up 16 percent. India was the leading source nation for immigrant scientists and engineers. Between 2003 and 2013, the number of U.S. scientists and engineers who immigrated from India nearly doubled from 515,000 to 950,000.

The report shows that foreign-born scientists and engineers are more likely to earn higher degrees than their U.S.-born counterparts. In 2013, 9 percent of immigrants earned a doctorate compared to 3.8 percent of U.S.-born citizens.

Nearly 15 percent of immigrants earned their highest degree in computer and mathematical science, and over 20 percent earned engineering degrees. For U.S.-born citizens, those shares were about 8 percent and 10 percent respectively.

The percentage of immigrants in the U.S. tech workforce is likely to keep increasing. While talk of a STEM skills shortage in the U.S. could be overblown, tech companies have been pushing for more H-1B visas, and corporate recruiters often cite STEM worker shortages. Last year, President Obama announced immigration plans that make it easier for foreign-born students to stay and work in the U.S.

The challenge might be training and retaining skilled, engaged scientists and engineers. Some foreign policy experts believe that the United States should wage a war for global talent and nab the world’s best scientists and engineers while the U.S. economy is getting stronger.

What do you think? Does the United States need to offer even more H-1B visas? Is that what’s necessary to attract the world’s best talent?

The Google Lunar XPrize Race Is Officially On

Today, the Google Lunar XPrize (GLXP) announced that Israeli team SpaceIL is the first to sign a verified launch contract that covers the first leg of its journey to the moon. The educational nonprofit’s spacecraft is slated to launch on a SpaceX Falcon 9 rocket in the second half of 2017.

This is huge news for the GLXP, which is offering at least US $20 million to the first private team to land on the moon and perform certain tasks. The lunar deadline is currently set at the end of 2017, but a more pressing deadline has been looming for quite some time.

Until now, we were just months away from what could have been the contest’s real expiration date. According to the present rules, if no team showed evidence of a launch agreement by the end of 2015, the contest would be over.

With SpaceIL’s contract, at least one team is now officially in the running for the prize. “It really is the new space race now,” GLXP’s senior director Chanda Gonzales says.

As I explained earlier this year, finding a way to get off the ground has been big challenge for GLXP competitors. Rocket berths are expensive, and while a team could potentially launch more cheaply as a secondary payload, it’s a tough pitch when you’re proposing adding a spacecraft loaded with potentially explosive rocket fuel.

“It’s more than tricky,” says SpaceIL CEO Eran Privman. “We found it almost impossible.” Privman explains that the team at one point had been working on securing a launch with Russia. “There we managed to get an initial agreement, but it failed due to geopolitical issues.” Attempts to secure a berth as a secondary also failed, he says, so “we decided to change the game.”

In the end, the team signed a contract with Seattle-based launch broker Spaceflight. SpaceIL’s craft will launch in a cluster containing more than 20 payloads, each contracting with Spaceflight. The launch will cost SpaceIL more than US $10 million, Privman says. (It’s not clear how much more than $10 million the actual fee is, but it’s likely a fraction of the oft-quoted “front-door price” for a whole Falcon 9, some $60 million.)

According to the revised GLXP rules laid out in May, any remaining teams who wish to compete must provide notification of a launch contract by the end of next year. But it may not take that long before we see other teams join the starting line.

Last week, aspiring lunar mining company Moon Express announced that it has signed a launch contract with Rocket Lab, a New Zealand-based start-up that’s hoping to drive down the cost of space access. 

 The contract is for five launches, totalling about US $30 million, Daven Maharaj, Moon Express vice president of operations told me on Friday.

Moon Express hopes to launch on Rocket Lab’s Electron rocket, which is expected to begin test launches shortly. Moon Express has reserved two Electron launches in 2017, which could be a good move if there are any issues with the new rocket. “There is definitely some risk there,” Maharaj says. “That’s one of the advantages—by picking two slots we’re basically guaranteeing ourselves a scheduled relaunch.”

The GLXP has yet to receive the launch contract documentation from Moon Express, Gonzales says. When it does, the agreement will be evaluated as the SpaceIL one was, she says, on both financial and technical terms. 

Of course, even with a more established company, no flight can be guaranteed, and no flight date is set in stone. SpaceX is still working on resuming flights following a launch failure in June. “I believe that [the delay] shouldn’t affect the manifest in the second half of 2017,” SpaceIL’s Privman says. “But you know that predicting is very unpredictable.”

Even with these uncertainties, it’s exciting to see the Google Lunar XPrize move into this new stage. The competition was first announced in 2007, and its original deadline for claiming the full top prize was 2012. It’s been a long road. Perhaps one day soon it will end with a few new landers dipping their feet in lunar regolith.

Follow Rachel Courtland on Twitter at @rcourt.

Tunnel Transistor May Meet Power Needs of Future Chips

A new kind of transistor consumes 90 percent less power than conventional transistors, dramatically exceeding a theoretical limit for electronics, researchers say. These findings could one day lead to super-dense low-power circuits as well as ultra-sensitive biosensors and gas sensors, the investigators added.

The relentless advance of computing power over the past half-century has relied on constant miniaturization of field-effect transistors (FETs), which serve as the building blocks of most microchips. Transistors act like switches that flick on and off to represent data as zeroes and ones.

A key challenge that FETs now face is reducing the power they consume. The switching properties of conventional FETs are currently restricted by a theoretical limit of 60 millivolts per decade of current at room temperature. This limit, known as the subthreshold swing, means that each 60-millivolt increase in voltage leads to a 10-fold increase in current. Lowering the swing would yield better channel control, so switching would require less energy.

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Fujitsu Makes a Terahertz Receiver Small Enough for a Smartphone

It’s a good time to be alive for pixel peepers. TV makers are pushing 4K-resolution sets to replace our present 1080p screens; Apple’s iMacs sport a 5K resolution; and NHK, Japan’s national broadcaster, is testing 8K broadcasting equipment, targeting 2020 and the Tokyo Olympics for its introduction.

To help wireless devices cope with the higher speeds demanded by such applications, Fujitsu has developed a 300-GHz prototype receiver compact enough to fit into a cellphone. Though limited to about 1 meter in range, the company says the device can download 4K and 8K video almost instantly.

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How Atoms Dance in Dielectrics

Atoms within the tiny crystals in many dielectric and ferroelectric ceramics twist and dance when an electric field is turned on. But until now, nobody could tell exactly how they twisted and danced, even though understanding those movements could be the key to developing more compact, higher performance capacitors and condensers.

In a new Scientific Reports paper, researchers at North Carolina State University—with colleagues from the U.S. National Institute of Standards and Technology and the University of New South Wales—show how new ways of analyzing X-ray diffraction data can reveal the details in a ceramic’s structural response to an electric field.

A ceramic can be a complex jumble of amorphous material that glues together crystalline particles of different sizes in different orientations. Traditionally, scientists probe crystal structures by reading the interference patterns produced by X-rays passing through them. They usually analyze only the primary signal, the strongest bands or brightest rings, which give information on the overall structure. This works well on homogeneous material in regular lattices. In a heterogeneous ceramic, though, with crystals pointing every which way, a lot of detail is buried in the faint secondary signals and diffusion patterns.

The NCSU-led team captured this detail by applying the pair distribution function (PDF). The method, first described in the 1960s but used increasingly over the past decade, lets researchers read all of the signals in a wedge of the diffraction pattern to calculate the length and orientation of the bonds between pairs of atoms. (See diagram.) Researchers take snapshots of the ceramic with and without an applied electric field, taking a census of how many microcrystals are in which orientations in each condition.

"A good analogy would be that analyzing the bright rings is like examining a skyscraper from far away and determining that each office is 500 square feet,” said NCSU’s Tedi-Marie Usher in a press release. “However, by also analyzing the weak X-rays scattered from the sample, we can determine that some offices are 400 square feet and others are 600 square feet, and some have the desk on the east side, and others have the desk on the north side."

The research team analyzed three perovskite materials— barium titanate (BaTiO3), sodium bismuth titanate (Na0.5Bi0.5TiO3), and strontium titanate (SrTiO3)—all members of a class of ceramics with useful dielectric, ferroelectric, and piezoelectric properties.

In an electric field, dielectrics become polarized and ferroelectrics reverse their polarity. This segregation—positive charge on one side, negative on the other, nobody in the middle—impedes current flow across the gap, letting energy build up. The material’s relative permittivity (or dielectric constant) is an index of how effectively it can store energy as an electric field. Air and a vacuum have permittivities of 1 (or very close to it). Silicon’s is 12. In barium titanate (which is also the first piezoelectric ceramic identified), the permittivity can range up from 1,200 to 10,000 or more.

As the material polarizes, its atoms reorient themselves in their crystal lattices. In sodium bismuth titanate, for example, bismuth atoms align with the electric field, changing their relationships with the surrounding titanium ions. (See animation. The bismuth atoms are shown in purple, the titanium in blue.)

“Dipolar effects are known to have large contributions to dielectric permittivity,” said NCSU’s Jacob Jones, the team leader, in a press release.  “The measurement tells us the population of dipoles that are reorienting. We could combine this information with the microscopic spontaneous dipole magnitude and calculate a net contribution to the macroscopic dielectric permittivity.”

Right now, there appears to be no one-size-fits-all mechanism for structural shifts in dielectric ceramics.

 “One of the interesting findings here is that each of the three dielectric materials we tested exhibited very different behaviors at the atomic level,” Jones said. “There was no single atomic behavior that accounted for dielectric properties across the materials."

So there is much more to be learned. Said Jones:

Of immediate interest are a broad range of dielectric materials that exhibit complicated (and elusive) structures. For example, perovskites with components Na0.5 Bi0.5 TiO3 [sodium bismuth titanate], K0.5Bi0.5TiO3 [potassium bismuth titanate], and Pb(Mg0.33Nb0.67)O3 [lead magnesium niobate] and their solid solutions. These compounds exhibit unique local structures that will respond to field differently. This is a useful technique to reveal interesting physical origins of unique dielectric, piezoelectric, and ferroelectric properties of these materials. We are also interested in extending this technique to an emerging class of high entropy alloys (HEAs) and entropy-stabilized oxides (ESOs), where unique elements may behave differently in response to mechanical stress or electric fields.  The unique local behavior of the elements in these multi-element materials is not accessible in traditional diffraction measurements.


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