Monthly Archives: November 2013

Nov. 19, 2013: Myths & Realities of the DIYbio Movement event at Woodrow Wilson Center (Washington, DC)

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The Synthetic Biology Project at the Woodrow Wilson International Center for Scholars is releasing a report tomorrow (Tuesday, Nov. 19, 2013) titled: Myths & Realities of the DIYbio Movement. If you’re lucky enough to be in Washington, DC, you can attend the live event,

As the Do-It-Yourself Biology (DIYbio) community has grown, so have concerns among media and policymakers about these science enthusiasts’ ability to wield DNA and manipulate life. In the words of one Wall Street Journal headline, “In Attics and Closets, ‘Biohackers’ Discover their Inner Frankenstein.”

The realities of DIYbio, however, contradict the media myths. In its first-ever survey of DIYbio practitioners, the Synthetic Biology Project at the Woodrow Wilson International Center for Scholars finds the community to be far different from these fearful and often sensationalist representations.

The report challenges seven widely held beliefs about DIYbio practitioners, particularly about their labs, capabilities and goals. The survey finds that the science they practice is far more benign than described in the popular press. In fact, the report suggests that the DIYbio community offers national education and entrepreneurship opportunities, rather than over-inflated risks. The report concludes with six policy recommendations based on the survey results.

What: Join us at the Wilson Center on Nov. 19 for the release of the survey results and analysis, followed by a panel discussion.

Copies of the report will be available at the event and online on Nov. 19 here: http://www.synbioproject.org/events/archive/6673/

You must register to attend the event. Please RSVP here: http://bit.ly/1gGZZLd [there will possibly be a webcast posted at a later date]

More information can be found here: http://www.wilsoncenter.org/event/myths-realities-the-diybio-movement

When: Nov. 19, 2013 from noon – 2:00 p.m. EST (Light lunch available at 11:30 am.)

Who: Daniel Grushkin, co-founder of Genspace and Wilson Center Fellow
Jason Bobe, co-founder of DIYbio.org
Todd Kuiken, Synthetic Biology Project

Where: Woodrow Wilson International Center for Scholars
5th Floor Conference Room
Ronald Reagan Building
1300 Pennsylvania Ave NW
Washington, D.C.

For directions, visit: http://www.wilsoncenter.org/directions

To learn more about the Synthetic Biology Project, visit: http://www.synbioproject.org/about/

According to the Center’s event webpage, there may be a webcast of the event available but it seems they won’t be livestreaming so you will have to wait until it’s posted.

I have mentioned Genspace here in a Sept. 21, 2012 posting titled: A tooth and art installation in Vancouver (Canada) and bodyhacking and DIY (do-it-yourself) culture in the US. Scroll down about 1/2 way to find the mention of Genspace (New York’s Community Biolab) and its activities. (At the time, I was focused on the bodyhacking aspect of DIYbio.)

Jason Bobe’s DIYbio.org is new to me. Here’s a little more about the organization from the homepage (Note: Links have been removed),

DIYbio.org was founded in 2008 with the mission of establishing a vibrant, productive and safe community of DIY biologists.  Central to our mission is the belief that biotechnology and greater public understanding about it has the potential to benefit everyone.

Join the global discussion
Find local groups, people and events near you
Read the diybio blog
Ask a biosafety expert your safety question
Subscribe to the quarterly postcard update
Browse the library of DIY lab hardware
Get the diybio logo and contact info

I checked out the organization’s Local Groups webpage and found three groups in Canada,,

DIYbio Toronto (this is the only city that has any current activity listed on its site)

Welcome to DIYbio Vancouver!

Biospace (Victoria, BC)

Where’s the science? Stephen Hawking’s Brave New World debuts Nov. 15, 2013

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Yesterday, Nov. 14, 2013, I happened to catch Dr. Carin Bondar being interviewed on a local (Vancouver, Canada) television (tv) programme about her upcoming appearances as one of the hosts of Stephen Hawking’s Brave New World series (season two) being debuted tonight (Nov. 15, 2013). While enthusiastic about this latest venture, Dr. Bondar didn’t offer much science information during the interview where she focused on her adventures as part of a virtual military team and her surprise at some of the work being done in the field of prosthetics. There’s a bit more detail about the programme (not the science) in Bondar’s Nov. 12, 2013 blog entry on the Huffington Post website,

One of the highlights of my career thus far was being involved in a groundbreaking television series Stephen Hawking’s Brave New World premiering on Discovery World. A co-operative project between Handel Productions (Canada) and IWC (England), the series showcases some of the most mind-blowing new technologies that will impact our daily lives in the not-too-distant future.

Each of the six, one-hour episodes is narrated by Professor Stephen Hawking, world-renown physicist and author of the best-seller A Brief History of Time, and is comprised of the investigations of a team of five scientists who travel the world — Myself and Professor Chris Eliasmith from Canada, Dr. Daniel Kraft from the US, and Professor Jim Al-Khalili and Dr. Aarathi Prasad from the UK.

The premiere episode, called Inspired by Nature, is all about how we need only to look to the natural world for some of the most awe-inspiring inventions. Millions of years of evolution have resulted in some highly complex and innovative strategies for life across the animal kingdom…and this episode shows us how humans are attempting to re-create them for our own purposes.
…
Stephen Hawking’s Brave New World premieres Friday, November 15 at 8 p.m. ET/10 p.m. PT on Discovery World.

Bondar’s personal blog offers very little more, from a Nov. 1, 2013 posting,

Hi Everyone! I’m thrilled to be one of the presenters on season two of ‘Brave New World with Stephen Hawking’, which will premiere on November 15th. Shooting took place last spring all over the states. It was a crazy, exhausting whirlwind from Atlanta to San Diego, LA, Houston, Pittsburgh and Boston, but it was one of the coolest experiences of my life. I love this promo image of me in a Faraday (bird) cage at the Boston Museum of Science.

…

The Discovery World website’s programme webpage provides a bit more detail (where’s the science?) about the first three shows in the series,

STEPHEN HAWKING’S BRAVE NEW WORLD: “Inspired by Nature”
Hawking and his team investigate groundbreaking innovations in science inspired by nature. Aarathi Prasad road tests two of the most advanced all-terrain robots in the world designed to go where humans and vehicles can’t; Chris Eliasmith examines an extraordinary new fabric that mimics the adhesive ability of gecko feet and bonds to any surface; Daniel Kraft visits Vancouver-based Nuytco Research where underwater subs are used to simulate zero gravity to train astronauts for deep space exploration; Jim Al-Khalili examines how re-engineering a virus can prevent pandemics; and Carin Bondar discovers how Nikola Tesla’s remarkable dream of wireless power is finally being realized.

STEPHEN HAWKING’S BRAVE NEW WORLD: “Code Red”
Hawking and his team examine new inventions that will change how humans deal with crises in the future. Chris Eliasmith looks into a revolutionary pilotless helicopter (the K-Max), that can fly and perform complex manoeuvres on its own; Daniel Kraft tests out the latest high-tech bomb disposal robot; Jim Al-Khalili checks out a sniper rifle equipped with jet fighter target tracking technology; Carin Bondar examines face recognition binoculars that can identify criminals within 15 seconds; then, Aarathi Prasad examines a lifesaving breakthrough that allows oxygen to be injected directly into the bloodstream.
STEPHEN HAWKING’S BRAVE NEW WORLD: “Virtual World”
Hawking and his team investigate technology transforming the idea of reality. Carin Bondar takes part in a remarkable 3D virtual training program created for the military; Aarathi Prasad tests a new system that maps locations inaccessible by GPS; Daniel Kraft investigates 3D bio-printing where computer designs can be turned into living tissue; Chris Eliasmith tests the latest in gaming technology – a breakthrough in virtual reality that promises the most immersive experience yet; and Jim Al-Khalili tests a computer that can read the human mind.

It would have been nice to find out a little more about the science and a little less about the exciting aspects of these adventures. Perhaps the producers thought it best to confine the science to the broadcast.

The local tv programme where Dr. Bondar was interviewed is called The Rush and while the Nov. 14, 2012 interview has yet (as of Nov. 15, 2013, 13H30 or 1:30 pm PDT) to be posted online, you should be able to find it shortly.

I have mentioned Chris Eliasmith (University of Waterloo, Ontario, Canada) here before, notably in my November 29, 2012 posting about his work simulating neurons in the virtual world.

Surviving 39 minutes at room temperature—recordbreaking for quantum materials

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There are two news releases about this work which brings quantum computing a step closer to reality. I’ll start with the Nov. 15, 2013 Simon Fraser University (SFU; located in Vancouver, Canada) news release (Note: A link has been removed),,

An international team of physicists led by Simon Fraser University professor Mike Thewalt has overcome a key barrier to building practical quantum computers, taking a significant step to bringing them into the mainstream.

In their record-breaking experiment conducted on SFU’s Burnaby campus, [part of Metro Vancouver] the scientists were able to get fragile quantum states to survive in a solid material at room temperature for 39 minutes. For the average person, it may not seem like a long time, but it’s a veritable eternity to a quantum physicist.

“This opens up the possibility of truly long-term coherent information storage at room temperature,” explains Thewalt.

Quantum computers promise to significantly outperform today’s machines at certain tasks, by exploiting the strange properties of subatomic particles. Conventional computers process data stored as strings of ones or zeroes, but quantum objects are not constrained to the either/or nature of binary bits.

Instead, each quantum bit – or qubit – can be put into a superposition of both one and zero at the same time, enabling them to perform multiple calculations simultaneously. For instance, this ability to multi-task could allow quantum computers to crack seemingly secure encryption codes.

“A powerful universal quantum computer would change technology in ways that we already understand, and doubtless in ways we do not yet envisage,” says Thewalt, whose research was published in Science today.

“It would have a huge impact on security, code breaking and the transmission and storage of secure information. It would be able to solve problems which are impossible to solve on any conceivable normal computer. It would be able to model the behaviour of quantum systems, a task beyond the reach of normal computers, leading, for example, to the development of new drugs by a deeper understanding of molecular interactions.”

However, the problem with attempts to build these extraordinary number-crunchers is that superposition states are delicate structures that can collapse like a soufflé if nudged by a stray particle, such as an air molecule.

To minimize this unwanted process, physicists often cool their qubit systems to almost absolute zero (-273 C) and manipulate them in a vacuum. But such setups are finicky to maintain and, ultimately, it would be advantageous for quantum computers to operate robustly at everyday temperatures and pressures.

“Our research extends the demonstrated coherence time in a solid at room temperature by a factor of 100 – and at liquid helium temperature by a factor of 60 (from three minutes to three hours),” says Thewalt.

“These are large, significant improvements in what is possible.”

The November 15, 2013 University of Oxford news release (also on EurekAlert), features their own researcher and more information (e.g., the previous record for maintaining coherence of a solid state at room temperature),

An international team including Stephanie Simmons of Oxford University report in this week’s Science a test performed as part of a project led by Mike Thewalt of Simon Fraser University, Canada, and colleagues. …

In the experiment, the team raised the temperature of a system, in which information is encoded in the nuclei of phosphorus atoms in silicon, from -269°C to 25°C and demonstrated that the superposition states survived at this balmy temperature for 39 minutes – outside of silicon the previous record for such a state’s survival at room temperature was around two seconds. [emphasis mine] The team even found that they could manipulate the qubits as the temperature of the system rose, and that they were robust enough for this information to survive being ‘refrozen’ (the optical technique used to read the qubits only works at very low temperatures).

‘Thirty-nine minutes may not seem very long but as it only takes one-hundred-thousandth of a second to flip the nuclear spin of a phosphorus ion – the type of operation used to run quantum calculations – in theory over two million operations could be applied in the time it takes for the superposition to naturally decay by 1%. Having such robust, as well as long-lived, qubits could prove very helpful for anyone trying to build a quantum computer,’ said Stephanie Simmons of Oxford University’s Department of Materials, an author of the paper.

…

The team began with a sliver of silicon doped with small amounts of other elements, including phosphorus. Quantum information was encoded in the nuclei of the phosphorus atoms: each nucleus has an intrinsic quantum property called ‘spin’, which acts like a tiny bar magnet when placed in a magnetic field. Spins can be manipulated to point up (0), down (1), or any angle in between, representing a superposition of the two other states.

The team prepared their sample at just 4°C above absolute zero (-269°C) and placed it in a magnetic field. Additional magnetic field pulses were used to tilt the direction of the nuclear spin and create the superposition states. When the sample was held at this cryogenic temperature, the nuclear spins of about 37% of the ions – a typical benchmark to measure quantum coherence – remained in their superposition state for three hours. The same fraction survived for 39 minutes when the temperature of the system was raised to 25°C.

…

There is still some work ahead before the team can carry out large-scale quantum computations. The nuclear spins of the 10 billion or so phosphorus ions used in this experiment were all placed in the same quantum state. To run calculations, however, physicists will need to place different qubits in different states. ‘To have them controllably talking to one another – that would address the last big remaining challenge,’ said Simmons.

Even for the uninitiated, going from a record of two seconds to 39 minutes has to raise an eyebrow.

Here’s a link to and a citation for the paper,

Room-Temperature Quantum Bit Storage Exceeding 39 Minutes Using Ionized Donors in Silicon-28.by Kamyar Saeedi, Stephanie Simmons, Jeff Z. Salvail, Phillip Dluhy, Helge Riemann, Nikolai V. Abrosimov, Peter Becker, Hans-Joachim Pohl, John J. L. Morton, & Mike L. W. Thewalt.  Science 15 November 2013: Vol. 342 no. 6160 pp. 830-833 DOI: 10.1126/science.1239584

This paper is behind a paywall.

ETA Nov. 18 ,2013:  The University College of London has also issued a Nov. 15, 2013 news release on EurekAlert about this work. While some of this is repetitive, I think there’s enough new information to make this excerpt worthwhile,

The team even found that they could manipulate the qubits as the temperature of the system rose, and that they were robust enough for this information to survive being ‘refrozen’ (the optical technique used to read the qubits only works at very low temperatures). 39 minutes may not sound particularly long, but since it only takes a tiny fraction of a second to run quantum computations by flipping the spin of phosphorus ions (electrically charged phosphorus atoms), many millions of operations could be carried out before a system like this decays.

“This opens up the possibility of truly long-term coherent information storage at room temperature,” said Mike Thewalt (Simon Fraser University), the lead researcher in this study.

The team began with a sliver of silicon doped with small amounts of other elements, including phosphorus. They then encoded quantum information in the nuclei of the phosphorus atoms: each nucleus has an intrinsic quantum property called ‘spin’, which acts like a tiny bar magnet when placed in a magnetic field. Spins can be manipulated to point up (0), down (1), or any angle in between, representing a superposition of the two other states.

The team prepared their sample at -269 °C, just 4 degrees above absolute zero, and placed it in a magnetic field. They used additional magnetic field pulses to tilt the direction of the nuclear spin and create the superposition states. When the sample was held at this cryogenic temperature, the nuclear spins of about 37 per cent of the ions – a typical benchmark to measure quantum coherence – remained in their superposition state for three hours. The same fraction survived for 39 minutes when the temperature of the system was raised to 25 °C.

 

Electronic skin and its evolution

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Michael Berger has featured an article in the journal Advanced Materials, which reviews 25 years of work on e-skin (aka, electronic skin or artificial skin) in his Nov. 15, 2013 Nanowerk Spotlight series article ,

Advances in materials, fabrication strategies and device designs for flexible and stretchable electronics and sensors make it possible to envision a not-too-distant future where ultra-thin, flexible circuits based on inorganic semiconductors can be wrapped and attached to any imaginable surface, including body parts and even internal organs. Robotic technologies will also benefit as it becomes possible to fabricate electronic skin (‘e-skin’) that, for instance, could allow surgical robots to interact, in a soft contacting mode, with their surroundings through touch. In addition to giving robots a finer sense of touch, engineers believe that e-skin technology could also be used to create things like wallpapers that double as touchscreen displays and dashboard laminates that allow drivers to adjust electronic controls with the wave of a hand.

Here’s a link to and a citation for the 25-year review of work on e-skin,

25th Anniversary Article: The Evolution of Electronic Skin (E-Skin): A Brief History, Design Considerations, and Recent Progress by Mallory L. Hammock, Alex Chortos, Benjamin C.-K. Tee, Jeffrey B.-H. Tok, and Zhenan Bao. Advanced Materials Volume 25, Issue 42, pages 5997–6038, November 13, 2013 Article first published online: 22 OCT 2013 DOI: 10.1002/adma.201302240

© 2013 WILEY-VCH Verlag GmbH & Co. KGaA, Weinheim

The review article is behind a paywall but Berger’s synopsis offers a good overview* and tidbits such as this timeline (Berger offers a larger version) which includes important moments in science fiction (Note: Links in the caption have been removed),

Figure 1. A brief chronology of the evolution of e-skin. We emphasize several science fictional events in popular culture that inspired subsequent critical technological advancements in the development of e-skin. Images reproduced with permission: “micro-structured pressure sensor,”[18] “stretchable OLEDs,”[20b] “stretchable OPVs,”[21a] “stretchable, transparent e-skin,”[22] “macroscale nanowire e-skin,”[23a] “rechargeable, stretchable batteries,”[137] “interlocked e-skin.”[25] Copyright, respectively, 2010, 2009, 2012, 2005, 2010, 2013, 2012. Macmillan Publishers Ltd. “Flexible, active-matrix e-skin” image reproduced with permission.[26a] Copyright, 2004. National Academy of Sciences USA. “Epidermal electronics” image reproduced with permission.[390a] Copyright, American Association for the Advancement of Science. “Stretchable batteries” image reproduced with permission.[27] “Infrared e-skin” image reproduced with permission.[8b] Copyright 2001, IEEE. “Anthropomorphic cybernetic hand” image reproduced with permission.[426] Copyright 2006, IEEE. [downloaded from http://onlinelibrary.wiley.com.proxy.lib.sfu.ca/doi/10.1002/adma.201302240/full]

Figure 1. A brief chronology of the evolution of e-skin. We emphasize several science fictional events in popular culture that inspired subsequent critical technological advancements in the development of e-skin. Images reproduced with permission: “micro-structured pressure sensor,”[18] “stretchable OLEDs,”[20b] “stretchable OPVs,”[21a] “stretchable, transparent e-skin,”[22] “macroscale nanowire e-skin,”[23a] “rechargeable, stretchable batteries,”[137] “interlocked e-skin.”[25] Copyright, respectively, 2010, 2009, 2012, 2005, 2010, 2013, 2012. Macmillan Publishers Ltd. “Flexible, active-matrix e-skin” image reproduced with permission.[26a] Copyright, 2004. National Academy of Sciences USA. “Epidermal electronics” image reproduced with permission.[390a] Copyright, American Association for the Advancement of Science. “Stretchable batteries” image reproduced with permission.[27] “Infrared e-skin” image reproduced with permission.[8b] Copyright 2001, IEEE. “Anthropomorphic cybernetic hand” image reproduced with permission.[426] Copyright 2006, IEEE. [downloaded from http://onlinelibrary.wiley.com.proxy.lib.sfu.ca/doi/10.1002/adma.201302240/full]

Here’s an excerpt from the review article outlining the 1970s – 1990s period featuring some of the science fiction which has influenced the science (Note: Links have been removed),

The prospect of creating artificial skin was in many ways inspired by science fiction, which propelled the possibility of e-skin into the imagination of both the general public as well as the scientific community. One of the first science fiction books to explore the use of mechanical replacement organs was Caidin’s Cyborg in 1971, on which the famed Six Million Dollar Man television series about a man with a bionic replacement arm and eye was later based (1974).[4] Shortly after, at the beginning of the 1980s, George Lucas created a vision of a future with e-skin in the famous Star Wars series. In particular, he depicted a scene showing a medical robot installing an electronic hand with full sensory perception on the main character, Luke Skywalker.[5] Shortly after, in 1984, the Terminator movie series depicted humanoid robots and even a self-healing robot.[6] These fictitious renditions of e-skin took place against a real-life backdrop of vibrant microelectronics research that began bridging science fiction with scientific reality.

Early technological advancements in the development of e-skin were concomitant with their science fiction inspirations. In 1974, Clippinger et al. demonstrated a prosthetic hand capable of discrete sensor feedback.[7] Nearly a decade later, Hewlett-Packard (HP) marketed a personal computer (HP-150) that was equipped with a touchscreen, allowing users to activate functions by simply touching the display. It was the first mass-marketed electronic device capitalizing on the intuitive nature of human touch. In 1985, General Electric (GE) built the first sensitive skin for a robotic arm using discrete infrared sensors placed on a flexible sheet at a resolution of ≈5 cm.[8] The fabricated sensitive skin was proximally aware of its surroundings, allowing the robot’s arm to avert potential obstacles and effectively maneuver within its physical environment. Despite the robotic arm’s lack of fingers and low resolution, it was capable of demonstrating that electronics integrated into a membrane could allow for natural human–machine interaction. For example, the robotic arm was able to ‘dance’ with a ballerina without any pre-programmed motions.[8] In addition to the ability of an artificial skin to interact with its surroundings, it is equally critical that the artificial skin mimics the mechanical properties of human skin to accommodate its various motions. Hence, to build life-like prosthetics or humanoid robots, soft, flexible, and stretchable electronics needed to be developed.

In the 1990s, scientists began using flexible electronic materials to create large-area, low-cost and printable sensor sheets. Jiang et al. proposed one of the first flexible sensor sheets for tactile shear force sensing by creating silicon (Si) micro-electro-mechanical (MEM) islands by etching thin Si wafers and integrating them on flexible polyimide foils.[9] Much work has since been done to enhance the reliability of large sensor sheets to mechanical bending.[10] Around the same time, flexible arrays fabricated from organic semiconductors began to emerge that rivaled the performance of amorphous Si.[11]

Just before the turn of the millennium, the first “Sensitive Skin Workshop” was held in Washington DC under the aegis of the National Science Foundation and the Defense Advanced Research Projects Agency, bringing together approximately sixty researchers from different sectors of academia, industry, and government. It was discovered that there was significant industrial interest in e-skins for various applications, ranging from robotics to health care. A summary of concepts outlined in the workshop was compiled by Lumelsky et al.[12] In the early 2000s, the pace of e-skin development significantly increased as a result of this workshop, and researchers began to explore different types of sensors that could be more easily integrated with microprocessors.

I have written about e-skin a number of times, most recently in a July 9, 2013 posting about work on flexible sensors and gold nanoparticles being conducted at Technion-Israel Institute of Technology. This review helps to contextualize projects such as the one at Technion and elsewhere.

*To avoid redundancy ‘synopsis’ was replaced by ‘overview’ on Oct. 19, 2015.

Cerium dixoide nanoparticle sponges and their electron clouds

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This research team is very excited about what they’ve accomplished (from a Nov. 12, 3013 news item on ScienceDaily),

A new chapter has been opened in our understanding of the chemical activity of nanoparticles says a team of international scientists. Using the X-ray beams of The European Synchrotron (ESRF) they showed that the electrons absorbed and released by cerium dioxide nanoparticles during chemical reactions behave in a completely different way than previously thought: the electrons are not bound to individual atoms but, like a cloud, distribute themselves over the whole nanoparticle. Inspired by the similarity of its shape, the scientists call this spatial distribution of particles an “electron sponge.”

The Nov. 12, 2013 European Synchrotron Radiation Facility news release (also on EurekAlert), which originated the news item, explains the scientists’ interest in cerium dioxide in more detail,

Today, cerium dioxide nanoparticles are widely used in industrial processes and also in consumer products. They are present, for example, in the walls of self-cleaning ovens and act as a hydrocarbon catalyst during the high temperature cleaning process. They are also a hot candidate for the next generation of lithium-ion batteries which will exhibit higher voltages and a greater storage capacity compared to today’s energy cells.

The element Cerium is abundant in the Earth’s crust and can easily be mined and purified. However, without a thorough understanding of the chemical processes happening on the surface of cerium dioxide nanoparticles, it is impossible to optimise their current and future use. And to address a more complex issue, it is also impossible to assess the limits of their safe use.

Most chemical reactions involve the transfer of an electron from one atom to another. In the past, it was believed that the electrons involved in a chemical reaction on the surface of a nanoparticle were localised in one of the atoms at the surface. To determine the behaviour of the electrons during the reaction, the scientists used the intense X-ray beams at the ESRF [European Synchrotron Radiation Facility] to probe solutions of nanoparticles in water and ethanol. The nanoparticles had a diameter of 3 nm and consisted of several thousands of molecules of cerium dioxide.

It is known that nanoparticles can change their behaviour under vacuum when studied with an electron microscope, for example. The scientists therefore carried out their experiment under realistic conditions, studying the nanoparticles in solution and in real time as the chemical reaction was taking place. “It was only possible to conduct these experiments in a liquid rather than under vacuum because we used X-rays as probes for the electron distribution.” says Jean Daniel Cafun [first author is Jean-Daniel Cafun from the ESRF].

In their experiment, the scientists were successful in observing the creation of the nanoparticles in solution and then how these nanoparticles eliminated highly reactive molecules (reactive oxygen species, or ROS) from the solution. This elimination process mimics the role of an important enzyme in living organisms – catalase – that protects cells from these aggressive molecules. Cancer patients undergoing radiation therapy have high levels of ROS in their bodies and ceria nanoparticles have been proposed as a way of reducing the levels of ROS and thus alleviating the negative impacts of the therapy on the patients. Throughout the chemical reaction, the electronic structure of the cerium atoms and thus the redistribution of the electron cloud was monitored. “It is crucial to be able to study the chemical processes of the particles in an environment that is close to conditions found in biological systems.” emphasizes Victor Puntes [Victor Puntes from the Universitá Autònoma of Barcelona, Catalan Institute of Nanotechnologies {Spain}].

“Scientists have been discussing the question: What happens when electrons are added to ceria nanoparticles? The work by Cafun et al. is a key study because it questions the present, widely accepted model and will lead the research in a new direction.” says Frank de Groot, an expert on nanomaterials at Utrecht University who did not take part in the experiment.

The next step, which has already been initiated, will be to assess whether non-localised electrons are a property of cerium dioxide only or also of other widely used nanoparticles like titanium dioxide. “In parallel, chemists have to revisit their theoretical models to explain the chemical behaviour of nanoparticles and to better understand how electrons are transferred in chemical reactions taking place on their surface.” concludes Pieter Glatzel [team leader Pieter Glatzel from The European Synchrotron {ESRF} in Grenoble {France}].

For anyone who’d like to explore this topic further,

Absence of Ce3+ Sites in Chemically Active Colloidal Ceria Nanoparticles by Jean-Daniel Cafun, Kristina O. Kvashnina, Eudald Casals, Victor F. Puntes, and Pieter Glatzel. ACS Nano, Article ASAP DOI: 10.1021/nn403542p Publication Date (Web): November 12, 2013
Copyright © 2013 American Chemical Society

This article is behind a paywall.

Almost Human (tv series), smartphones, and anxieties about life/nonlife

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The US-based Fox Broadcasting Company is set to premiere a new futuristic television series, Almost Human, over two nights, Nov. 17, and 18, 2013 for US and Canadian viewers. Here’s a description of the premise from its Wikipedia essay (Note: Links have been removed),

The series is set thirty-five years in the future when humans in the Los Angeles Police Department are paired up with lifelike androids; a detective who has a dislike for robots partners with an android capable of emotion.

One of the showrunners, Naren Shankar, seems to have also been functioning both as a science consultant and as a crime writing consultant,in addition to his other duties. From a Sept. 4, 2013 article by Lisa Tsering for Indiawest.com,

FOX is the latest television network to utilize the formidable talents of Naren Shankar, an Indian American writer and producer best known to fans for his work on “Star Trek: Deep Space Nine,” “Star Trek: Voyager” and “Star Trek: The Next Generation” as well as “Farscape,” the recently cancelled ABC series “Zero Hour” and “The Outer Limits.”

…

Set 35 years in the future, “Almost Human” stars Karl Urban and Michael Ealy as a crimefighting duo of a cop who is part-machine and a robot who is part-human. [emphasis mine]

…

“We are extrapolating the things we see today into the near future,” he explained. For example, the show will comment on the pervasiveness of location software, he said. “There will also be issues of technology such as medical ethics, or privacy; or how technology enables the rich but not the poor, who can’t afford it.”

Speaking at Comic-Con July 20 [2013], Shankar told media there, “Joel [J.H. Wyman] was looking for a collaboration with someone who had come from the crime world, and I had worked on ‘CSI’ for eight years.

“This is like coming back to my first love, since for many years I had done science fiction. It’s a great opportunity to get away from dismembered corpses and autopsy scenes.”

There’s plenty of drama — in the new series, the year is 2048, and police officer John Kennex (Karl Urban, “Dr. Bones” from the new “Star Trek” films) is trying to bounce back from one of the most catastrophic attacks ever made against the police department. Kennex wakes up from a 17-month coma and can’t remember much, except that his partner was killed; his girlfriend left him and one of his legs has been amputated and is now outfitted with a high-tech synthetic appendage. According to police department policy, every cop must partner with a robot, so Kennex is paired with Dorian (Ealy), an android with an unusual glitch that makes it have human emotions.

…

Shankar took an unusual path into television. He started college at age 16 and attended Cornell University, where he earned a B. Sc., an M.S. and a Ph.D. in engineering physics and electrical engineering, and was a member of the elite Kappa Alpha Society, he decided he didn’t want to work as a scientist and moved to Los Angeles to try to become a writer.

…

Shankar is eager to move in a new direction with “Almost Human,” which he says comes at the right time. “People are so technologically sophisticated now that maybe the audience is ready for a show like this,” he told India-West.

I am particularly intrigued by the ‘man who’s part machine and the machine that’s part human’ concept (something I’ve called machine/flesh in previous postings such as this May 9, 2012 posting titled ‘Everything becomes part machine’) and was looking forward to seeing how they would be integrating this concept along with some of the more recent scientific work being done on prosthetics and robots, given they had an engineer as part of the team (albeit with lots of crime writing experience), into the stories. Sadly, only days after Tserling’s article was published, Shankar parted ways with Almost Human according to the Sept. 10, 2013 posting on the Almost Human blog,

So this was supposed to be the week that I posted a profile of Naren Shankar, for whom I have developed a full-on crush–I mean, he has a PhD in Electrical Engineering from Cornell, he was hired by Gene Roddenberry to be science consultant on TNG, he was saying all sorts of great things about how he wanted to present the future in AH…aaaand he quit as co-showrunner yesterday, citing “creative differences.” That leaves Wyman as sole showrunner, with no plans to replace Shankar.

I’d like to base some of my comments on the previews, unfortunately, Fox Broadcasting,, in its infinite wisdom, has decided to block Canadians from watching Almost Human previews online. (Could someone please explain why? I mean, Canadians will be tuning in to watch or record for future viewing  the series premiere on the 17th & 18th of November 2013 just like our US neighbours, so, why can’t we watch the previews online?)

Getting back to machine/flesh (human with prosthetic)s and life/nonlife (android with feelings), it seems that Almost Human (as did the latest version of Battlestar Galactica, from 2004-2009) may be giving a popular culture voice to some contemporary anxieties being felt about the boundary or lack thereof between humans and machines and life/nonlife. I’ve touched on this topic many times both within and without the popular culture context. Probably one of my more comprehensive essays on machine/flesh is Eye, arm, & leg prostheses, cyborgs, eyeborgs, Deus Ex, and ableism from August 30, 2011, which includes this quote from a still earlier posting on this topic,

Here’s an excerpt from my Feb. 2, 2010 posting which reinforces what Gregor [Gregor Wolbring, University of Calgary] is saying,

This influx of R&D cash, combined with breakthroughs in materials science and processor speed, has had a striking visual and social result: an emblem of hurt and loss has become a paradigm of the sleek, modern, and powerful. Which is why Michael Bailey, a 24-year-old student in Duluth, Georgia, is looking forward to the day when he can amputate the last two fingers on his left hand.

“I don’t think I would have said this if it had never happened,” says Bailey, referring to the accident that tore off his pinkie, ring, and middle fingers. “But I told Touch Bionics I’d cut the rest of my hand off if I could make all five of my fingers robotic.” [originally excerpted from Paul Hochman’s Feb. 1, 2010 article, Bionic Legs, i-Limbs, and Other Super Human Prostheses You’ll Envy for Fast Company]

Here’s something else from the Hochman article,

But Bailey is most surprised by his own reaction. “When I’m wearing it, I do feel different: I feel stronger. As weird as that sounds, having a piece of machinery incorporated into your body, as a part of you, well, it makes you feel above human. [semphasis mine] It’s a very powerful thing.”

Bailey isn’t  almost human’, he’s ‘above human’. As Hochman points out. repeatedly throughout his article, this sentiment is not confined to Bailey. My guess is that Kennex (Karl Urban’s character) in Almost Human doesn’t echo Bailey’s sentiments and, instead feels he’s not quite human while the android, Dorian, (Michael Ealy’s character) struggles with his feelings in a human way that clashes with Kennex’s perspective on what is human and what is not (or what we might be called the boundary between life and nonlife).

Into this mix, one could add the rising anxiety around ‘intelligent’ machines present in real life, as well as, fiction as per this November 12 (?), 2013 article by Ian Barker for Beta News,

The rise of intelligent machines has long been fertile ground for science fiction writers, but a new report by technology research specialists Gartner suggests that the future is closer than we think.

“Smartphones are becoming smarter, and will be smarter than you by 2017,” says Carolina Milanesi, research vice president at Gartner. “If there is heavy traffic, it will wake you up early for a meeting with your boss, or simply send an apology if it is a meeting with your colleague. The smartphone will gather contextual information from its calendar, its sensors, the user’s location and personal data”.

Your smartphone will be able to predict your next move or your next purchase based on what it knows about you. This will be made possible by gathering data using a technique called “cognizant computing”.

…

Gartner analysts will be discussing the future of smart devices at the Gartner Symposium/ITxpo 2013 in Barcelona from November 10-14 [2013].

The Gartner Symposium/Txpo in Barcelona is ending today (Nov. 14, 2013) but should you be curious about it, you can go here to learn more.

This notion that machines might (or will) get smarter or more powerful than humans (or wizards) is explored by Will.i.am (of the Black Eyed Peas) and, futurist, Brian David Johnson in their upcoming comic book, Wizards and Robots (mentioned in my Oct. 6, 2013 posting),. This notion of machines or technology overtaking human life is also being discussed at the University of Cambridge where there’s talk of founding a Centre for the Study of Existential Risk (from my Nov. 26, 2012 posting)

The idea that robots of one kind or another (e.g. nanobots eating up the world and leaving grey goo, Cylons in both versions of Battlestar Galactica trying to exterminate humans, etc.) will take over the world and find humans unnecessary  isn’t especially new in works of fiction. It’s not always mentioned directly but the underlying anxiety often has to do with intelligence and concerns over an ‘explosion of intelligence’. The question it raises,’ what if our machines/creations become more intelligent than humans?’ has been described as existential risk. According to a Nov. 25, 2012 article by Sylvia Hui for Huffington Post, a group of eminent philosophers and scientists at the University of Cambridge are proposing to found a Centre for the Study of Existential Risk,

Could computers become cleverer than humans and take over the world? Or is that just the stuff of science fiction?

Philosophers and scientists at Britain’s Cambridge University think the question deserves serious study. A proposed Center for the Study of Existential Risk will bring together experts to consider the ways in which super intelligent technology, including artificial intelligence, could “threaten our own existence,” the institution said Sunday.

“In the case of artificial intelligence, it seems a reasonable prediction that some time in this or the next century intelligence will escape from the constraints of biology,” Cambridge philosophy professor Huw Price said.

When that happens, “we’re no longer the smartest things around,” he said, and will risk being at the mercy of “machines that are not malicious, but machines whose interests don’t include us.”

Our emerging technologies give rise to questions abut what constitutes life and where human might fit in. For example,

  • are sufficiently advanced machines a new form of life,?
  • what does it mean when human bodies are partially integrated at the neural level with machinery?
  • what happens when machines have feelings?
  • etc.

While this doesn’t exactly fit into my theme of life/nonlife or machine/flesh, this does highlight how some popular culture efforts are attempting to integrate real science into the storytelling. Here’s an excerpt from an interview with Cosima Herter, the science consultant and namesake/model for one of the characters on Orphan Black (from the March 29, 2013 posting on the space.ca blog),

Cosima Herter is Orphan Black’s Science Consultant, and the inspiration for her namesake character in the series. In real-life, Real Cosima is a PhD. student in the History of Science, Technology, and Medicine Program at the University of Minnesota, working on the History and Philosophy of Biology. Hive interns Billi Knight & Peter Rowley spoke with her about her role on the show and the science behind it…

Q: Describe your role in the making of Orphan Black.

A: I’m a resource for the biology, particularly insofar as evolutionary biology is concerned. I study the history and the philosophy of biology, so I do offer some suggestions and some creative ideas, but also help correct some of the misconceptions about science.  I offer different angles and alternatives to look at the way biological science is represented, so (it’s) not reduced to your stereotypical tropes about evolutionary biology and cloning, but also to provide some accuracy for the scripts.

– See more at: http://www.space.ca/article/Orphan-Black-science-consultant#sthash.7P36bbPa.dpuf

For anyone not familiar with the series, from the Wikipedia essay (Note: Links have been removed),

Orphan Black is a Canadian science fiction television series starring Tatiana Maslany as several identical women who are revealed to be clones.

Biology and lithium-air batteries

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Firstly, the biology in question is that of viruses and, secondly, research in lithium-air batteries has elicited big interest according to David Chandler’s November 13, 2013 Massachusetts Institute of Technology (MIT) news piece (also on EurekAlert and Nanowerk),

Lithium-air batteries have become a hot research area in recent years: They hold the promise of drastically increasing power per battery weight, which could lead, for example, to electric cars with a much greater driving range. But bringing that promise to reality has faced a number of challenges, ….

Now, MIT researchers have found that adding genetically modified viruses to the production of nanowires — wires that are about the width of a red blood cell, and which can serve as one of a battery’s electrodes — could help solve some of these problems.

Lithium-air batteries can also be referred to as lithiium-oxygen batteries, although Chandler does not choose to mix terms as he goes on to describe the process the researchers developed,

The researchers produced an array of nanowires, each about 80 nanometers across, using a genetically modified virus called M13, which can capture molecules of metals from water and bind them into structural shapes. In this case, wires of manganese oxide — a “favorite material” for a lithium-air battery’s cathode, Belcher says — were actually made by the viruses. But unlike wires “grown” through conventional chemical methods, these virus-built nanowires have a rough, spiky surface, which dramatically increases their surface area.

Belcher, the W.M. Keck Professor of Energy and a member of MIT’s Koch Institute for Integrative Cancer Research, explains that this process of biosynthesis is “really similar to how an abalone grows its shell” — in that case, by collecting calcium from seawater and depositing it into a solid, linked structure.

The increase in surface area produced by this method can provide “a big advantage,” Belcher says, in lithium-air batteries’ rate of charging and discharging. But the process also has other potential advantages, she says: Unlike conventional fabrication methods, which involve energy-intensive high temperatures and hazardous chemicals, this process can be carried out at room temperature using a water-based process.

Also, rather than isolated wires, the viruses naturally produce a three-dimensional structure of cross-linked wires, which provides greater stability for an electrode.

A final part of the process is the addition of a small amount of a metal, such as palladium, which greatly increases the electrical conductivity of the nanowires and allows them to catalyze reactions that take place during charging and discharging. Other groups have tried to produce such batteries using pure or highly concentrated metals as the electrodes, but this new process drastically lowers how much of the expensive material is needed.

Altogether, these modifications have the potential to produce a battery that could provide two to three times greater energy density — the amount of energy that can be stored for a given weight — than today’s best lithium-ion batteries, a closely related technology that is today’s top contender, the researchers say.

MIT has produced a video highlighting the researchers’ work (this runs longer than most of the materials I embed here at approximately 11 mins. 25 secs.),

For those who want to know more about this intriguing and speculative work,

Biologically enhanced cathode design for improved capacity and cycle life for lithium-oxygen batteries by Dahyun Oh, Jifa Qi, Yi-Chun Lu, Yong Zhang, Yang Shao-Horn, & Angela M. Belcher. Nature Communications 4, Article number: 2756 doi:10.1038/ncomms3756 Published 13 November 2013

This article is behind a paywall.

ETA Nov. 15, 2013: Dexter Johnson offers more context and information, including commercialization issues, about lithium-air batteries and lithium-ion batteries in his Nov. 14, 2013 posting on the Nanoclast blog (on the IEEE [Institute of Electrical and Electronics Engineers] website).

Deadline for submissions to 2014 TAPPI International Conference on Nanotechnology of Renewable Materials in Vancouver, Canada extended

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A November 12, 2013 news item on TextileWorld.com announced the new deadline, Nov. 22, 2014, (original deadline was Nov. 5, 2013) for the 2014 TAPPI (Technical Association for the Pulp, Paper, Packaging and Converting Industries) nanotechnology conference submissions,

The Norcross, Ga.-based Technical Association for the Pulp, Paper, Packaging and Converting Industries (TAPPI) has issued a call for 300-word abstracts for presentations to be given at the 2014 TAPPI International Conference on Nanotechnology for Renewable Materials, to be held June 23-26 at the Fairmont Hotel Vancouver in Vancouver, Canada.

… Abstracts focused on additive manufacturing, 3-D printing and other industrial manufacturing applications are preferred.

…. Deadline for submissions is November 22, 2013. …

You can find the 2014 TAPPI Nanotechnology conference website here and the PDF of the Call for Submissions here. Here’s a list of suggested topics from the Call for Submissions,

Preparation & Characterization
Renewable Nanomaterial Isolation & Separation
Cellulose nanocrystals and nanofibrils
Plant, algal, bacterial and other sources
Lignin, heteropolysaccharides, chitosan, etc.
Lab & Pilot-Scale Production
Process Optimization
New isolation & extraction methods
Drying processes
Separation processes forr enewable nanomaterials
Metrology
Sizing, mechanical,chemical, optical and surfaceproperties
Purity, molecular weight, crystallinity, etc.
Thermal, electrical and other properties
Toxicity, biocompatibility & Biodegradability
Self- and Direct-Assembly & Functionalities Nanostructured Materials by Self-assembly
Nano manufacture & self-assembly
Photonic bandgap pigments for special optical effects
Controlled delivery, immobilization, etc.
Novel Nano-enabled Functionalities
Surface modification and responsive materials
Optical effects for novel photonic applications
Inorganic materials template by cellulose nanocrystals
Novel electric, magnetic and piezoelectric effects
Sustainable polymer electronics
Carbon Fibers from Biomass
Production, characterization & uses
Membranes & Filters
New Membrane technologies
Air, water and bio filtration
Biomedical Applications
Ligament replacements, scaffolds, advanced woundtechnology
Bioactive materials
Immunoassays
Rheology and Dispersion Phenomena
Rheology behavior in aqueous and non-aqueous systems
Viscoelastic properties, etc.
Composites, Hydrogels, and Aerogels
Nanocomposites and Renewable Nanomaterials
Nano-reinforced films and fibers
Biomimetic nanocomposites
Porous materials, gels and aerogels, foams and multiphase dispersed system
Bio-derived matrix polymers
Processing
Organic/Inorganic Hybrids
Catalysts
Flexible electronics, etc.
Metal functionalization, ALD, etc,
Manufacturing Applications
Rheology and Rheological Modifiers
Industrial processing applications, e.g., food, pharma, painting, coating, oil, gas, etc.
Dispersion and flocculation
Additive Manufacturing
Raw nanomaterials
Medical applications
3D printing
Paper, Board & Packaging
Coatings & Fillers
High modulus paper coatings
Wear and scratch resistant coatings
Flexible Packaging
Barriers
Printing Technologies
Printing inks
Smart materials
Sensing technologies
Computer Modeling and Simulation
Multiscale Modeling
Solvation structure and hydrodynamics
Environmental, Health and Safety Issues
Workplace Safety & Standards
Current understanding andcritical gaps
Consumer perception and regulations
Management of risks and perceptions
Sustainability assessment, LCA

In digging about for information about the TAPPI nanotechnology conference,, I came across a reference to a meeting hosted by PAPTAC (Pulp and Paper Technical Association of Canada) regarding nanocrystalline cellulose (NCC) or, as it’s also known, cellulose nanocrystals (CNC)  held in June 2013 in Victoria, BC (preparatory to the 17th [2013] International Symposium
on Wood, Fibre and Pulping Chemistry [ISWFPC] conference in Vancouver) I thought the CNC programme interesting enough to reproduce here,

8:05
Keynote lecture by Professor Arthur Carty, Executive Director of the Waterloo Institute for Nanotechnology
Small World, Large Impact: Driving a Materials Revolution Through Nanotechnology
9:00
Dr Clive Willis, Former Vice President of National Research Council of Canada (NRC)
Standardization of CNC: Needs and Challenges
9:45 Coffee Break
10:15
Dr Richard Berry, VP and CTO, CelluForce Inc.
CelluForce—The Journey So Far
11:00
Dr Alan Rudie, USDA Forest Products Lab
Pilot Scale Production of Cellulose Nanocrystals and Cellulose Nanofibrils:
The US Need, FPL Process and Status
11:45
Professor Derek Gray, McGill University
Preparation and Optical Properties of Films Containing Cellulose Nanocrystals
12:30 Lunch
13:30
Professor Akira Isogai, Tokyo University
Applications of TEMPO-oxidized Cellulose Nanofibres to Gas Barrier Films and Nanocomposites
14:15
Dr Laurent Heux, CERMAV
Physico-chemical and Self-assembling Properties of CNC in Water and Organic Solvents
15:00
Professor Emily Cranston, McMaster University
Surface-modified Cellulose Nanocrystals: Characterization, Purification and Applications
15:45 Coffee Break
16:15
Dr Carole Fraschini, FPInnovations
Particle Issues in the Determination of Nanocellulose Particle Size
17:00
Dr Andriy Kovalenko, National Institute of Nanotechnology (NINT-NRC)
Multi-scale Modelling of the Structure, Thermodynamics,
and Effective Interactions of CNC in Different Solutions
19:00 Dinner and Award—Host: Dr J Bouchard

Monday, June 10
…
8:30
Dr Wadood Hamad, FPInnovations
Cellulose Nanocrystals for Advanced Functional Nanocomposites
9:15
Professor Michael Tam, University of Waterloo [emphasis mine]
Cellulose Nanocrystals—Functionalization, Characterization and Applications in Personal Care Systems
10:00
Professor Mark MacLachlan, University of British Columbia
Cellulose Nanocrystal-derived Porous Materials… With a Twist
10:45 Coffee Break
11:15
Professor Yaman Boluk, University of Alberta
Cellulose Nanocrystals in Soft Matter and Smart Applications
12:00
Professor Orlando Rojas, North Carolina State University
Self- and Direct-assembly of Cellulose Nanocrystals at Solid, Liquid and Air Interfaces: Fundamentals and Applications
12:45 Lunch
13:45
Professor John Simonsen, Oregon State University
Atomic Layer Deposition on Cellulose Nanocrystal Aerogels
14:30
Professor Alain Dufresne, Grenoble INP—Pagora
Processing of Nanocellulose Based Polymer Nanocomposites
15:15
Professor Monique Lacroix, INRS-Institut Armand-Frappier
The Use of Cellulose Nanocrystals in Food Packaging
16:00 Coffee Break
16:30
Professor Mark Andrews, McGill University
Cellulose NanocrystalsMake Light Work
17:15
Dr David Plackett, University of British Columbia
Cellulose Nanocrystals as a Vehicle for Delivery of Antibiotics

I don’t think it’s a coincidence that Michael Tam bears the same last name as Janelle Tam whose father is named Michael and both of whom lived in Waterloo when the then 16 year old Janelle Tam placed first in the 2013 Sanofi BioGENEius Challenge Competition (my May 11, 2012 posting).

There you have it, Good luck with your 2014 TAPPI nanotechnology conference submission.

Duke University’s (North Carolina, US) Center for Environmental Implications of NanoTechnology (CEINT) wins $15M grant

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A Nov. 13, 2013 news item on Azonano announces that the Center for Environmental Implications of Nanotechnology (CEINT) at Duke University has been awarded $15M,

A pioneering, multi-institution research center headquartered at Duke’s Pratt School of Engineering has just won $15-million grant renewal from the National Science Foundation and the US Environmental Protection Agency to continue learning more about where nanoparticles accumulate, how they interact with other chemicals and how they affect the environment.

Founded in 2008, the Center for Environmental Implications of NanoTechnology (CEINT) has been evaluating the effect of long-term nanomaterial exposure on organisms and ecosystems.

“The previous focus has been on studying simple, uniform nanomaterials in simple environments,” said Mark Wiesner, James L. Meriam Professor of Civil & Environmental Engineering and director of CEINT. “As we look to the next five years, we envision a dramatically different landscape. We will be evaluating more complex nanomaterials in more realistic natural environments such as agricultural lands and water treatment systems where these materials are likely to be found.”

The Nov. 11, 2013 Duke University news release by Karyn Hede, which originated the news item, provides some history and context for CEINT (Note: Links have been removed),

When CEINT formed, little research had been done on how materials manufactured at the nanoscale—about 1/10,000th the diameter of a human hair—enter the environment and whether their size and unique properties render them a new category of environmental risk. For example, nanoparticles can be highly reactive with other chemicals in the environment and had been shown to disrupt activities in living organisms. Indeed, nanosilver is used in clothing precisely because it effectively kills odor-causing bacteria.

To tackle this expansive research agenda, CEINT leadership assembled a multi-institutional research team encompassing expertise in ecosystems biology, chemistry, geology, materials science, computational science, mathematical modeling and other specialties, to complement its engineering expertise. The Center has 29 faculty collaborators, as well as 76 graduate and undergraduate students participating in research. Over its first five years, CEINT has answered some of the most pressing questions about environmental risk and has learned where to focus future research.

The center also pioneered the use of a new test chamber, called a mesocosm, that replicates a small wetland environment. “Over the long term, we want to evaluate how nanoparticles bioaccumulate in complex food webs,” said Emily Bernhardt, an associate professor of biology at Duke and ecosystem ecologist who helped design the simulated ecosystems. “The additional funding will allow us to study the subtle effect of low-dose exposure on ecosystems over time, as well as complex interactions among nanoparticles and other environmental contaminants.”

Looking forward, the investigators at CEINT plan to expand the use of systems modeling and to create a “knowledge commons,” a place to store various kinds of data that can then be analyzed as a whole, said CEINT Executive Director Christine Hendren.

“Our investigators and collaborators are located across the globe,” Hendren added. “We are committed to disseminating information that can be translated into responsible regulatory frameworks and that will be available to compare with results of future research.”

…

Key findings from CEINT’s first five years include:

Naturally occurring nanomaterials far outnumber engineered particles. CEINT scientist Michael Hochella, a geoscientist at Virginia Tech, inventoried nanoparticles and concluded that natural nanoparticles are found everywhere, from dust in the atmosphere to sea spray to volcanoes. The environmental risks of these natural nanomaterials are difficult to separate from engineered nanomaterials.

Engineered nanoparticles change once they enter the environment. Gregory V. Lowry, deputy director of CEINT and professor at Carnegie Mellon University, Pittsburgh, along with colleagues from the University of Birmingham, U.K. and the University of South Carolina found that the relatively large surface area of nanoparticles makes them highly reactive once they enter the environment. These transformations will alter their movement and toxicity and must be considered when studying nanomaterials. Their review article on this topic was named the best feature article of 2012 by the journal Environmental Science and Technology.

Nanoparticles can be visualized, even in complex environmental samples. A research team led by CEINT investigators Jie Liu, associate professor of chemistry at Duke, and CEINT Director Mark Wiesner showed that more than a dozen types of engineered nanoparticles, including silver, gold, and titanium dioxide, along with carbon nanotubes, can be surveyed using a technique called hyperspectral imaging, which measures light scattering caused by different types of nanoparticles. The new technique, co-developed by postdoctoral researcher Appala Raju Badireddy, is sensitive enough to analyze nanoparticles found in water samples ranging from ultrapurified to wastewater. It will be used in future long-term studies of how nanoparticles move and accumulate in ecological systems.

It is possible to estimate current and future volume of engineered nanomaterials. Understanding the volume of nanomaterials being produced and released into the environment is a crucial factor in risk assessment. CEINT researchers led by Christine Hendren measured the upper- and lower-bound annual U.S. production of five classes of nanomaterials, totaling as much as a combined 40,000 metric tons annually as of 2011.

Silver nanoparticles caused environmental stress in a simulated wetland environment. CEINT has developed  “mesocosms,”  open-air terrarium-like structures that simulate wetland ecosystems that can be evaluated over time. Even low doses of silver nanoparticles used in many consumer products produced about a third less biomass in a mesocosm. The researchers will now  look at how nanomaterials are transferred between organisms in a mesocosm.

I have written about CEINT and its work, including the mesocosm, many times. My August 15, 2011 posting offers an introduction to the CEINT mesocosm.

University of Toronto’s (Canada) invisibility cloak

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University of Toronto researchers, Michael Selvanayagam and George V. Eleftheriades, have offered a popular summary of their work. from the popular summary (on the website where they’ve published their academic paper),

We “see” a physical object by detecting electromagnetic waves scattered from the object. A device that can “correct” or cancel that scattering would take the notion of a magic invisibility cloak from the realm of science fiction to reality. In fact, such physical devices already exist, accomplishing their feat based on metamaterials that bend light around the object to be cloaked, “correcting” the scattering. Designing metamaterials with the right light-bending properties for this purpose is, however, quite challenging, and the designs often require a thick “cloak.” An alternative approach to this problem is “active cloaking”: surrounding the object to be cloaked with electromagnetic sources that are carefully tuned to cancel the electromagnetic field scattered by the object. In this work, we demonstrate the first experimental realization of such a thin active cloak for microwaves.

The sources we have used are specially designed antennas and phase shifters, which can be configured into thin layers with flexibility in shape. We have succeeded in cloaking a sizable metallic cylinder by properly tuning the phase of the radiation from the antennas so that the radiation cancels the field scattered by the cylinder. We have gone a step further than cloaking and have also demonstrated how the object can be disguised as another object by tuning the antennas in a controlled way. The catch with active cloaking, however, is that knowledge of the incident field is required to tune the antennas. To tackle this issue, we have discussed some potential solutions that also utilize the antennas as sensors to detect the incident field.

Future work along this line will aim to extend the bandwidth of the cloak (with respect to pulsed incident fields) as well as design active cloaks that can adaptively respond to an incident field.

A Nov. 12, 2013 news item on ScienceDaily, offers information augmenting the popular summary,

Professor George Eleftheriades and PhD student Michael Selvanayagam have designed and tested a new approach to cloaking — by surrounding an object with small antennas that collectively radiate an electromagnetic field. The radiated field cancels out any waves scattering off the cloaked object. Their paper ‘Experimental demonstration of active electromagnetic cloaking’ appears today in the journal Physical Review X.

“We’ve taken an electrical engineering approach, but that’s what we are excited about,” says Eleftheriades. “It’s very practical.”

Picture a mailbox sitting on the street. When light hits the mailbox and bounces back into your eyes, you see the mailbox. When radio waves hit the mailbox and bounce back to your radar detector, you detect the mailbox. Eleftheriades and Selvanyagam’s system wraps the mailbox in a layer of tiny antennas that radiate a field away from the box, cancelling out any waves that would bounce back. In this way, the mailbox becomes undetectable to radar.

The Nov. 13, 2013 University of Toronto news release, which originated the news item and was posted a day later, provides more specific details about the research,

“We’ve demonstrated a different way of doing it,” says Eleftheriades. “It’s very simple: instead of surrounding what you’re trying to cloak with a thick metamaterial shell, we surround it with one layer of tiny antennas, and this layer radiates back a field that cancels the reflections from the object.”

Their experimental demonstration effectively cloaked a metal cylinder from radio waves using one layer of loop antennas. The system can be scaled up to cloak larger objects using more loops, and Eleftheriades says the loops could become printed and flat, like a blanket or skin.

For now, the antenna loops must be manually attuned to the electromagnetic frequency they need to cancel. But in future, researchers say, they could function both as sensors and active antennas, adjusting to different waves in real time, much like the technology behind noise-cancelling headphones.

Work on developing a functional invisibility cloak began around 2006, but early systems were necessarily large and clunky – if you wanted to cloak a car, for example, in practice you would have to completely envelop the vehicle in many layers of metamaterials in order to effectively “shield” it from electromagnetic radiation. The sheer size and inflexibility of that approach makes it impractical for real-world uses.

Earlier attempts to make thin cloaks were not adaptive and active, and could work only for specific small objects.

The cloaking technology holds possiblities that go beyond obvious applications such as hiding military vehicles or conducting surveillance operations. For example, structures that interrupt signals from cellular base stations could be cloaked to allow signals to pass by freely.

The system can also alter the signature of a cloaked object, making it appear bigger, smaller, or even shifting it in space. And though their tests showed the cloaking system works with radio waves, re-tuning it to work with Terahertz (T-rays) or light waves could use the same principle as the necessary antenna technology matures.

For those who feel inclined to explore this work further,

Experimental Demonstration of Active Electromagnetic Cloaking by Michael Selvanayagam and George V. Eleftheriades. Phys. Rev. X (Volume 3 Issue 4) or Phys. Rev. X 3, 041011 (2013) [13 pages]  DOI: 10.1103/PhysRevX.3.041011

Published by the American Physical Society under the terms of the Creative Commons Attribution 3.0 License. Further distribution of this work must maintain attribution to the author(s) and the published article’s title, journal citation, and DOI.

This article is open access.