Category Archives: military

Could CRISPR (clustered regularly interspaced short palindromic repeats) be weaponized?

On the occasion of an American team’s recent publication of research where they edited the germline (embryos), I produced a three-part series about CRISPR (clustered regularly interspaced short palindromic repeats), sometimes referred to as CRISPR/Cas9, (links offered at end of this post).

Somewhere in my series, there’s a quote about how CRISPR could be used as a ‘weapon of mass destruction’ and it seems this has been a hot topic for the last year or so as James Revill, research fellow at the University of Sussex, references in his August 31, 2017 essay on theconversation.com (h/t phys.org August 31, 2017 news item), Note: Links have been removed,

The gene editing technique CRISPR has been in the limelight after scientists reported they had used it to safely remove disease in human embryos for the first time. This follows a “CRISPR craze” over the last couple of years, with the number of academic publications on the topic growing steadily.

There are good reasons for the widespread attention to CRISPR. The technique allows scientists to “cut and paste” DNA more easily than in the past. It is being applied to a number of different peaceful areas, ranging from cancer therapies to the control of disease carrying insects.

Some of these applications – such as the engineering of mosquitoes to resist the parasite that causes malaria – effectively involve tinkering with ecosystems. CRISPR has therefore generated a number of ethical and safety concerns. Some also worry that applications being explored by defence organisations that involve “responsible innovation in gene editing” may send worrying signals to other states.

Concerns are also mounting that gene editing could be used in the development of biological weapons. In 2016, Bill Gates remarked that “the next epidemic could originate on the computer screen of a terrorist intent on using genetic engineering to create a synthetic version of the smallpox virus”. More recently, in July 2017, John Sotos, of Intel Health & Life Sciences, stated that gene editing research could “open up the potential for bioweapons of unimaginable destructive potential”.

An annual worldwide threat assessment report of the US intelligence community in February 2016 argued that the broad availability and low cost of the basic ingredients of technologies like CRISPR makes it particularly concerning.

A Feb. 11, 2016 news item on sciencemagazine.org offers a précis of some of the reactions while a February 9, 2016 article by Antonio Regalado for the Massachusetts Institute of Technology’s MIT Technology Review delves into the matter more deeply,

Genome editing is a weapon of mass destruction.

That’s according to James Clapper, [former] U.S. director of national intelligence, who on Tuesday, in the annual worldwide threat assessment report of the U.S. intelligence community, added gene editing to a list of threats posed by “weapons of mass destruction and proliferation.”

Gene editing refers to several novel ways to alter the DNA inside living cells. The most popular method, CRISPR, has been revolutionizing scientific research, leading to novel animals and crops, and is likely to power a new generation of gene treatments for serious diseases (see “Everything You Need to Know About CRISPR’s Monster Year”).

It is gene editing’s relative ease of use that worries the U.S. intelligence community, according to the assessment. “Given the broad distribution, low cost, and accelerated pace of development of this dual-use technology, its deliberate or unintentional misuse might lead to far-reaching economic and national security implications,” the report said.

The choice by the U.S. spy chief to call out gene editing as a potential weapon of mass destruction, or WMD, surprised some experts. It was the only biotechnology appearing in a tally of six more conventional threats, like North Korea’s suspected nuclear detonation on January 6 [2016], Syria’s undeclared chemical weapons, and new Russian cruise missiles that might violate an international treaty.

The report is an unclassified version of the “collective insights” of the Central Intelligence Agency, the National Security Agency, and half a dozen other U.S. spy and fact-gathering operations.

Although the report doesn’t mention CRISPR by name, Clapper clearly had the newest and the most versatile of the gene-editing systems in mind. The CRISPR technique’s low cost and relative ease of use—the basic ingredients can be bought online for $60—seems to have spooked intelligence agencies.

….

However, one has to be careful with the hype surrounding new technologies and, at present, the security implications of CRISPR are probably modest. There are easier, cruder methods of creating terror. CRISPR would only get aspiring biological terrorists so far. Other steps, such as growing and disseminating biological weapons agents, would typically be required for it to become an effective weapon. This would require additional skills and places CRISPR-based biological weapons beyond the reach of most terrorist groups. At least for the time being.

A July 5, 2016 opinion piece by Malcolm Dando for Nature argues for greater safeguards,

In Geneva next month [August 2016], officials will discuss updates to the global treaty that outlaws the use of biological weapons. The 1972 Biological Weapons Convention (BWC) was the first agreement to ban an entire class of weapons, and it remains a crucial instrument to stop scientific research on viruses, bacteria and toxins from being diverted into military programmes.

The BWC is the best route to ensure that nations take the biological-weapons threat seriously. Most countries have struggled to develop and introduce strong and effective national programmes — witness the difficulty the United States had in agreeing what oversight system should be applied to gain-of-function experiments that created more- dangerous lab-grown versions of common pathogens.

As scientific work advances — the CRISPR gene-editing system has been flagged as the latest example of possible dual-use technology — this treaty needs to be regularly updated. This is especially important because it has no formal verification system. Proposals for declarations, monitoring visits and inspections were vetoed by the United States in 2001, on the grounds that such verification threatened national security and confidential business information.

Even so, issues such as the possible dual-use threat from gene-editing systems will not be easily resolved. But we have to try. Without the involvement of the BWC, codes of conduct and oversight systems set up at national level are unlikely to be effective. The stakes are high, and after years of fumbling, we need strong international action to monitor and assess the threats from the new age of biological techniques.

Revill notes the latest BWC agreement and suggests future directions,

This convention is imperfect and lacks a way to ensure that states are compliant. Moreover, it has not been adequately “tended to” by its member states recently, with the last major meeting unable to agree a further programme of work. Yet it remains the cornerstone of an international regime against the hostile use of biology. All 178 state parties declared in December of 2016 their continued determination “to exclude completely the possibility of the use of (biological) weapons, and their conviction that such use would be repugnant to the conscience of humankind”.

These states therefore need to address the hostile potential of CRISPR. Moreover, they need to do so collectively. Unilateral national measures, such as reasonable biological security procedures, are important. However, preventing the hostile exploitation of CRISPR is not something that can be achieved by any single state acting alone.

As such, when states party to the convention meet later this year, it will be important to agree to a more systematic and regular review of science and technology. Such reviews can help with identifying and managing the security risks of technologies such as CRISPR, as well as allowing an international exchange of information on some of the potential benefits of such technologies.

Most states supported the principle of enhanced reviews of science and technology under the convention at the last major meeting. But they now need to seize the opportunity and agree on the practicalities of such reviews in order to prevent the convention being left behind by developments in science and technology.

Experts (military, intelligence, medical, etc.) are not the only ones concerned about CRISPR according to a February 11, 2016 article by Sharon Begley for statnews.com (Note: A link has been removed),

Most Americans oppose using powerful new technology to alter the genes of unborn babies, according to a new poll — even to prevent serious inherited diseases.

They expressed the strongest disapproval for editing genes to create “designer babies” with enhanced intelligence or looks.

But the poll, conducted by STAT and Harvard T.H. Chan School of Public Health, found that people have mixed, and apparently not firm, views on emerging genetic techniques. US adults are almost evenly split on whether the federal government should fund research on editing genes before birth to keep children from developing diseases such as cystic fibrosis or Huntington’s disease.

“They’re not against scientists trying to improve [genome-editing] technologies,” said Robert Blendon, professor of health policy and political analysis at Harvard’s Chan School, perhaps because they recognize that one day there might be a compelling reason to use such technologies. An unexpected event, such as scientists “eliminating a terrible disease” that a child would have otherwise inherited, “could change people’s views in the years ahead,” Blendon said.

But for now, he added, “people are concerned about editing the genes of those who are yet unborn.”

A majority, however, wants government regulators to approve gene therapy to treat diseases in children and adults.

The STAT-Harvard poll comes as scientists and policy makers confront the ethical, social, and legal implications of these revolutionary tools for changing DNA. Thanks to a technique called CRISPR-Cas9, scientists can easily, and with increasing precision, modify genes through the genetic analog of a computer’s “find and replace” function.

I find it surprising that there’s resistance to removing diseases found in the germline (embryos). When they were doing public consultations on nanotechnology, the one area where people tended to be quite open to research was health and medicine. Where food was concerned however, people had far more concerns.

If you’re interested in the STAT-Harvard poll, you can find it here. As for James Revill, he has written a more substantive version of this essay as a paper, which is available here.

On a semi-related note, I found STAT (statnews.com) to be a quite interesting and accessibly written online health science journal. Here’s more from the About Us page (Note: A link has been removed),

What’s STAT all about?
STAT is a national publication focused on finding and telling compelling stories about health, medicine, and scientific discovery. We produce daily news, investigative articles, and narrative projects in addition to multimedia features. We tell our stories from the places that matter to our readers — research labs, hospitals, executive suites, and political campaigns.

Why did you call it STAT?
In medical parlance, “stat” means important and urgent, and that’s what we’re all about — quickly and smartly delivering good stories. Read more about the origins of our name here.

Who’s behind the new publication?
STAT is produced by Boston Globe Media. Our headquarters is located in Boston but we have bureaus in Washington, New York, Cleveland, Atlanta, San Francisco, and Los Angeles. It was started by John Henry, the owner of Boston Globe Media and the principal owner of the Boston Red Sox. Rick Berke is executive editor.

So is STAT part of The Boston Globe?
They’re distinct properties but the two share content and complement one another.

Is it free?
Much of STAT is free. We also offer STAT Plus, a premium subscription plan that includes exclusive reporting about the pharmaceutical and biotech industries as well as other benefits. Learn more about it here.

Who’s working for STAT?
Some of the best-sourced science, health, and biotech journalists in the country, as well as motion graphics artists and data visualization specialists. Our team includes talented writers, editors, and producers capable of the kind of explanatory journalism that complicated science issues sometimes demand.

Who’s your audience?
You. Even if you don’t work in science, have never stepped foot in a hospital, or hated high school biology, we’ve got something for you. And for the lab scientists, health professionals, business leaders, and policy makers, we think you’ll find coverage here that interests you, too. The world of health, science, and medicine is booming and yielding fascinating stories. We explore how they affect us all.

….

As promised, here are the links to my three-part series on CRISPR,

Part 1 opens the series with a basic description of CRISPR and the germline research that occasioned the series along with some of the other (non-weapon) ethical issues and patent disputes that are arising from this new technology. CRISPR and editing the germline in the US (part 1 of 3): In the beginning

Part 2 covers three critical responses to the reporting and between them describe the technology in more detail and the possibility of ‘designer babies’.  CRISPR and editing the germline in the US (part 2 of 3): ‘designer babies’?

Part 3 is all about public discussion or, rather, the lack of and need for according to a couple of social scientists. Informally, there is some discussion via pop culture and Joelle Renstrom notes although she is focused on the larger issues touched on by the television series, Orphan Black and as I touch on in my final comments. CRISPR and editing the germline in the US (part 3 of 3): public discussions and pop culture

Finally, I hope to stumble across studies from other countries about how they are responding to the possibilities presented by CRISPR/Cas9 so that I can offer a more global perspective than this largely US perspective. At the very least, it would be interesting to find it if there differences.

Nanowire fingerprint technology

Apparently this technology from France’s Laboratoire d’électronique des technologies de l’information (CEA-Leti) will make fingerprinting more reliable. From a Sept. 5, 2017 news item on Nanowerk,

Leti today announced that the European R&D project known as PiezoMAT has developed a pressure-based fingerprint sensor that enables resolution more than twice as high as currently required by the U.S. Federal Bureau of Investigation (FBI).

The project’s proof of concept demonstrates that a matrix of interconnected piezoelectric zinc-oxide (ZnO) nanowires grown on silicon can reconstruct the smallest features of human fingerprints at 1,000 dots per inch (DPI).

“The pressure-based fingerprint sensor derived from the integration of piezo-electric ZnO nanowires grown on silicon opens the path to ultra-high resolution fingerprint sensors, which will be able to reach resolution much higher than 1,000 DPI,” said Antoine Viana, Leti’s project manager. “This technology holds promise for significant improvement in both security and identification applications.”

A Sept. 5, 2017 Leti press release, which originated the news item, delves further,

The eight-member project team of European companies, universities and research institutes fabricated a demonstrator embedding a silicon chip with 250 pixels, and its associated electronics for signal collection and post-processing. The chip was designed to demonstrate the concept and the major technological achievements, not the maximum potential nanowire integration density. Long-term development will pursue full electronics integration for optimal sensor resolution.

The project also provided valuable experience and know-how in several key areas, such as optimization of seed-layer processing, localized growth of well-oriented ZnO nanowires on silicon substrates, mathematical modeling of complex charge generation, and synthesis of new polymers for encapsulation. The research and deliverables of the project have been presented in scientific journals and at conferences, including Eurosensors 2016 in Budapest.

The 44-month, €2.9 million PiezoMAT (PIEZOelectric nanowire MATrices) research project was funded by the European Commission in the Seventh Framework Program. Its partners include:

  • Leti (Grenoble, France): A leading European center in the field of microelectronics, microtechnology and nanotechnology R&D, Leti is one of the three institutes of the Technological Research Division at CEA, the French Alternative Energies and Atomic Energy Commission. Leti’s activities span basic and applied research up to pilot industrial lines. www.leti-cea.com/cea-tech/leti/english
  • Fraunhofer IAF (Freiburg, Germany): Fraunhofer IAF, one of the leading research facilities worldwide in the field of III-V semiconductors, develops electronic and optical devices based on modern micro- and nanostructures. Fraunhofer IAF’s technologies find applications in areas such as security, energy, communication, health, and mobility. www.iaf.fraunhofer.de/en
  • Centre for Energy Research, Hungarian Academy of Sciences (Budapest, Hungary):  The Institute for Technical Physics and Materials Science, one of the institutes of the Research Centre, conducts interdisciplinary research on complex functional materials and nanometer-scale structures, exploration of physical, chemical, and biological principles, and their exploitation in integrated micro- and nanosystems www.mems.hu, www.energia.mta.hu/en
  • Universität Leipzig (Leipzig, Germany): Germany’s second-oldest university with continuous teaching, established in 1409, hosts about 30,000 students in liberal arts, medicine and natural sciences. One of its scientific profiles is “Complex Matter”, and contributions to PIEZOMAT are in the field of nanostructures and wide gap materials. www.zv.uni-leipzig.de/en/
  • Kaunas University of Technology (Kaunas, Lithuania): One of the largest technical universities in the Baltic States, focusing its R&D activities on novel materials, smart devices, advanced measurement techniques and micro/nano-technologies. The Institute of Mechatronics specializes on multi-physics simulation and dynamic characterization of macro/micro-scale transducers with well-established expertise in the field of piezoelectric devices. http://en.ktu.lt/
  • SPECIFIC POLYMERS (Castries, France): SME with twelve employees and an annual turnover of about 1M€, SPECIFIC POLYMERS acts as an R&D service provider and scale-up producer in the field of functional polymers with high specificity (>1000 polymers in catalogue; >500 customers; >50 countries). www.specificpolymers.fr/
  • Tyndall National Institute (Cork, Ireland): Tyndall National Institute is one of Europe’s leading research centres in Information and Communications Technology (ICT) research and development and the largest facility of its type in Ireland. The Institute employs over 460 researchers, engineers and support staff, with a full-time graduate cohort of 135 students. With a network of 200 industry partners and customers worldwide, Tyndall generates around €30M income each year, 85% from competitively won contracts nationally and internationally. Tyndall is a globally leading Institute in its four core research areas of Photonics, Microsystems, Micro/Nanoelectronics and Theory, Modeling and Design. www.tyndall.ie/
  • OT-Morpho (Paris, France): OT-Morpho is a world leader in digital security & identification technologies with the ambition to empower citizens and consumers alike to interact, pay, connect, commute, travel and even vote in ways that are now possible in a connected world. As our physical and digital, civil and commercial lifestyles converge, OT-Morpho stands precisely at that crossroads to leverage the best in security and identity technologies and offer customized solutions to a wide range of international clients from key industries, including Financial services, Telecom, Identity, Security and IoT. With close to €3bn in revenues and more than 14,000 employees, OT-Morpho is the result of the merger between OT (Oberthur Technologies) and Safran Identity & Security (Morpho) completed in 31 May 2017. Temporarily designated by the name “OT-Morpho”, the new company will unveil its new name in September 2017. For more information, visit www.morpho.com and www.oberthur.com

I have tended to take fingerprint technology for granted but last fall (2016) I stumbled on a report suggesting that forensic sciences, including fingerprinting, was perhaps not as conclusive as one might expect after watching fictional police procedural television programmes. My Sept. 23, 2016 posting features the US President’s Council of Advisors on Science and Technology (PCAST) released a report (‘Forensic Science in Criminal Courts: Ensuring Scientific Validity of Feature-Comparison Methods‘ 174 pp PDF).

The security of the Internet of Nano-Things with NanoMalaysia’s CEO Dr Rezal Khairi Ahmad

I’ve not come across the Internet of Nano-Things before and I’m always glad to be introduced to something new. In this case, I’m doubly happy as I get to catch up (a little) with the Malaysian nano scene. From an April 19, 2017 article by Avanti Kumar for mis.asia.com (Note: Links have been removed),

After being certified in 2011 as a nanocentre, national applied research agency MIMOS continued to make regular moves to boost Malaysia’s nanotechnology ambitions. This included helping to develop the national graphene action plan (NGAP 2020).

Much of the task of driving and commercialising the NGAP ecosystem is in the hands of NanoMalaysia, which was incorporated in 2011 as a company limited by guarantee (CLG) under Malaysia’s Ministry of Science, Technology and Innovation (MOSTI) to act as a business entity.

During another event in March 2016 where I saw that 360 new products were to be commercialised under NGAP, NanoMalaysia’s chief executive officer Dr. Rezal Khairi Ahmad said that benefits would include a US$5 billion impact on GNI (gross net income) and 9,000 related new jobs by the year 2020.

In his capacity as a keynote speaker at this year’s Computerworld Security Summit in Kuala Lumpur (20 April 2017), Dr Rezal agreed to a security-themed interview on this relatively new industry sector.  This is also part of a series of special security features.

To start, I asked Dr Rezal for a brief run-through of his role.

[RKA]  I’m the founding Chief Executive Officer and also Board Member of NanoMalaysia, Nano Commerce Sdn. Bhd, representing NanoMalaysia’s business interests, the Chairman of NanoVerify Sdn. Bhd, a nanotechnology certification entity and a Director of Nanovation Ventures Sdn. Bhd., an investment arm of NanoMalaysia.

Prior to this, I served as Acting Under-Secretary of National Nanotechnology Directorate, Ministry of Science, Technology and Innovation on the policy aspect of nanotechnology and vice president of [national investment body] Khazanah Nasional touching on human capital and investment research.

NanoMalaysia’s primary role in the development of Malaysia’s National Graphene Action Plan 2020 together with Agensi Inovasi Malaysia and PEMANDU [Performance Management & Delivery Unit attached to Prime Minister’s Office] is a major landmark in our journey to ensure Malaysia stays competitive in the global innovation landscape particularly in nanotechnology, which cuts across all industries including ICT [information and communications technologies].

Can you talk about graphene and its significance to local industry?

Graphene is touted as one of the game-changing advanced materials made of one atom-thick carbon and acknowledged by World Economic Forum [WEF] as no. 4 emerging technology in 2016.

Beyond being a fancy nano material, graphene plays a central role in the development of endogenous hardware aspects of Malaysia’s Internet of Things aspirations or the now evolved Internet of Nano-Things (IoNT). Some of these are:
-·Super small, lightweight and hyper-sensitive low-cost Graphene-based sensors and Radio Frequency ID (RFID)
– Higher speed, Low loss and power consumption graphene based optical transmitter and receiver for 5G systems
– Making IoNT a low-cost and practical industrial and domestic solutions in Malaysia.

Let’s move to the security aspects of nanotechnology: what’s your take on IoNT?

In the context of IoNT, which WEF acknowledged to be the top emerging technology in 2016, the current work-in-progress,  ‘ubiquitous’ deployment of sensors in Malaysia and worldwide, I certainly see increasing data security risks at the sensor, transmission, collection, processing and even analytics levels.

The initial industry approaches to IoNT data security will probably be polarised between cascaded and centralised system approaches.

I think some hacking attacks will obviously focus on data theft. I therefore foresee a trend favouring cascaded security – with both hardware, software and more advanced data encryption technologies in place.

What security steps do you currently advise?

The priority is to tackle potential data theft at every stage of IoNT systems.  The best-available preventive measures should include some versions of cascaded and embedded security in the form of hardware tags and advanced encryption.

To end, what’s your main message for business and IT leaders?

The digital era has removed the clear line that once separated State and Business as well as People. Everything and everyone is more interconnected. We are now an ecosystem both by chance and design. Cyber-attacks can be made to afflict either one and be used to hold any one at ransom thus creating a local or even global systemic chain reaction effect.

The connected world presents endless commercial, social and environmental development opportunities…and threats. The development and deployment of emerging cyber-related technologies, in particular IoNT – which promises a market size of US$9.69 billion by 2020 – should be done responsibly in the form of infused data security technologies to ensure prolific market acceptance and profitable returns.

For our part, NanoMalaysia is working with various parties locally and abroad push Malaysia’s strategic industry sectors to be relevant to the Fourth Industrial Revolution supported by cyber-physical systems manifesting into full automation, robots, artificial intelligence, de-centralised power generation, energy storage, water and food supplies, remote assets and logistics management and custom manufacturing requiring secured data sensing, traffic and analytics systems in place.

If you have the time, I advise reading the article in its entirety.

‘Mother of all bombs’ is a nanoweapon?

According to physicist, Louis A. Del Monte, in an April 14, 2017 opinion piece for Huffington Post.com, the ‘mother of all bombs ‘ is a nanoweapon (Note: Links have been removed),

The United States military dropped its largest non-nuclear bomb, the GBU-43/B Massive Ordnance Air Blast Bomb (MOAB), nicknamed the “mother of all bombs,” on an ISIS cave and tunnel complex in the Achin District of the Nangarhar province, Afghanistan [on Thursday, April 13, 2017]. The Achin District is the center of ISIS activity in Afghanistan. This was the first use in combat of the GBU-43/B Massive Ordnance Air Blast (MOAB).

… Although it carries only about 8 tons of explosives, the explosive mixture delivers a destructive impact equivalent of 11 tons of TNT.

There is little doubt the United States Department of Defense is likely using nanometals, such as nanoaluminum (alternately spelled nano-aluminum) mixed with TNT, to enhance the detonation properties of the MOAB. The use of nanoaluminum mixed with TNT was known to boost the explosive power of the TNT since the early 2000s. If true, this means that the largest known United States non-nuclear bomb is a nanoweapon. When most of us think about nanoweapons, we think small, essentially invisible weapons, like nanobots (i.e., tiny robots made using nanotechnology). That can often be the case. But, as defined in my recent book, Nanoweapons: A Growing Threat to Humanity (Potomac 2017), “Nanoweapons are any military technology that exploits the power of nanotechnology.” This means even the largest munition, such as the MOAB, is a nanoweapon if it uses nanotechnology.

… The explosive is H6, which is a mixture of five ingredients (by weight):

  • 44.0% RDX & nitrocellulose (RDX is a well know explosive, more powerful that TNT, often used with TNT and other explosives. Nitrocellulose is a propellant or low-order explosive, originally known as gun-cotton.)
  • 29.5% TNT
  • 21.0% powdered aluminum
  • 5.0% paraffin wax as a phlegmatizing (i.e., stabilizing) agent.
  • 0.5% calcium chloride (to absorb moisture and eliminate the production of gas

Note, the TNT and powdered aluminum account for over half the explosive payload by weight. It is highly likely that the “powdered aluminum” is nanoaluminum, since nanoaluminum can enhance the destructive properties of TNT. This argues that H6 is a nano-enhanced explosive, making the MOAB a nanoweapon.

The United States GBU-43/B Massive Ordnance Air Blast Bomb (MOAB) was the largest non-nuclear bomb known until Russia detonated the Aviation Thermobaric Bomb of Increased Power, termed the “father of all bombs” (FOAB), in 2007. It is reportedly four times more destructive than the MOAB, even though it carries only 7 tons of explosives versus the 8 tons of the MOAB. Interestingly, the Russians claim to achieve the more destructive punch using nanotechnology.

If you have the time, I encourage you to read the piece in its entirety.

Predicting how a memristor functions

An April 3, 2017 news item on Nanowerk announces a new memristor development (Note: A link has been removed),

Researchers from the CNRS [Centre national de la recherche scientifique; France] , Thales, and the Universities of Bordeaux, Paris-Sud, and Evry have created an artificial synapse capable of learning autonomously. They were also able to model the device, which is essential for developing more complex circuits. The research was published in Nature Communications (“Learning through ferroelectric domain dynamics in solid-state synapses”)

An April 3, 2017 CNRS press release, which originated the news item, provides a nice introduction to the memristor concept before providing a few more details about this latest work (Note: A link has been removed),

One of the goals of biomimetics is to take inspiration from the functioning of the brain [also known as neuromorphic engineering or neuromorphic computing] in order to design increasingly intelligent machines. This principle is already at work in information technology, in the form of the algorithms used for completing certain tasks, such as image recognition; this, for instance, is what Facebook uses to identify photos. However, the procedure consumes a lot of energy. Vincent Garcia (Unité mixte de physique CNRS/Thales) and his colleagues have just taken a step forward in this area by creating directly on a chip an artificial synapse that is capable of learning. They have also developed a physical model that explains this learning capacity. This discovery opens the way to creating a network of synapses and hence intelligent systems requiring less time and energy.

Our brain’s learning process is linked to our synapses, which serve as connections between our neurons. The more the synapse is stimulated, the more the connection is reinforced and learning improved. Researchers took inspiration from this mechanism to design an artificial synapse, called a memristor. This electronic nanocomponent consists of a thin ferroelectric layer sandwiched between two electrodes, and whose resistance can be tuned using voltage pulses similar to those in neurons. If the resistance is low the synaptic connection will be strong, and if the resistance is high the connection will be weak. This capacity to adapt its resistance enables the synapse to learn.

Although research focusing on these artificial synapses is central to the concerns of many laboratories, the functioning of these devices remained largely unknown. The researchers have succeeded, for the first time, in developing a physical model able to predict how they function. This understanding of the process will make it possible to create more complex systems, such as a series of artificial neurons interconnected by these memristors.

As part of the ULPEC H2020 European project, this discovery will be used for real-time shape recognition using an innovative camera1 : the pixels remain inactive, except when they see a change in the angle of vision. The data processing procedure will require less energy, and will take less time to detect the selected objects. The research involved teams from the CNRS/Thales physics joint research unit, the Laboratoire de l’intégration du matériau au système (CNRS/Université de Bordeaux/Bordeaux INP), the University of Arkansas (US), the Centre de nanosciences et nanotechnologies (CNRS/Université Paris-Sud), the Université d’Evry, and Thales.

 

Image synapse


© Sören Boyn / CNRS/Thales physics joint research unit.

Artist’s impression of the electronic synapse: the particles represent electrons circulating through oxide, by analogy with neurotransmitters in biological synapses. The flow of electrons depends on the oxide’s ferroelectric domain structure, which is controlled by electric voltage pulses.


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

Learning through ferroelectric domain dynamics in solid-state synapses by Sören Boyn, Julie Grollier, Gwendal Lecerf, Bin Xu, Nicolas Locatelli, Stéphane Fusil, Stéphanie Girod, Cécile Carrétéro, Karin Garcia, Stéphane Xavier, Jean Tomas, Laurent Bellaiche, Manuel Bibes, Agnès Barthélémy, Sylvain Saïghi, & Vincent Garcia. Nature Communications 8, Article number: 14736 (2017) doi:10.1038/ncomms14736 Published online: 03 April 2017

This paper is open access.

Thales or Thales Group is a French company, from its Wikipedia entry (Note: Links have been removed),

Thales Group (French: [talɛs]) is a French multinational company that designs and builds electrical systems and provides services for the aerospace, defence, transportation and security markets. Its headquarters are in La Défense[2] (the business district of Paris), and its stock is listed on the Euronext Paris.

The company changed its name to Thales (from the Greek philosopher Thales,[3] pronounced [talɛs] reflecting its pronunciation in French) from Thomson-CSF in December 2000 shortly after the £1.3 billion acquisition of Racal Electronics plc, a UK defence electronics group. It is partially state-owned by the French government,[4] and has operations in more than 56 countries. It has 64,000 employees and generated €14.9 billion in revenues in 2016. The Group is ranked as the 475th largest company in the world by Fortune 500 Global.[5] It is also the 10th largest defence contractor in the world[6] and 55% of its total sales are military sales.[4]

The ULPEC (Ultra-Low Power Event-Based Camera) H2020 [Horizon 2020 funded) European project can be found here,

The long term goal of ULPEC is to develop advanced vision applications with ultra-low power requirements and ultra-low latency. The output of the ULPEC project is a demonstrator connecting a neuromorphic event-based camera to a high speed ultra-low power consumption asynchronous visual data processing system (Spiking Neural Network with memristive synapses). Although ULPEC device aims to reach TRL 4, it is a highly application-oriented project: prospective use cases will b…

Finally, for anyone curious about Thales, the philosopher (from his Wikipedia entry), Note: Links have been removed,

Thales of Miletus (/ˈθeɪliːz/; Greek: Θαλῆς (ὁ Μῑλήσιος), Thalēs; c. 624 – c. 546 BC) was a pre-Socratic Greek/Phoenician philosopher, mathematician and astronomer from Miletus in Asia Minor (present-day Milet in Turkey). He was one of the Seven Sages of Greece. Many, most notably Aristotle, regard him as the first philosopher in the Greek tradition,[1][2] and he is otherwise historically recognized as the first individual in Western civilization known to have entertained and engaged in scientific philosophy.[3][4]

Nanozymes as an antidote for pesticides

Should you have concerns about exposure to pesticides or chemical warfare agents (timely given events in Syria as per this April 4, 2017 news item on CBC [Canadian Broadcasting News Corporation] online) , scientists at the Lomonosov Moscow State University have developed a possible antidote according to a March 8,, 2017 news item on phys.org,

Members of the Faculty of Chemistry of the Lomonosov Moscow State University have developed novel nanosized agents that could be used as efficient protective and antidote modalities against the impact of neurotoxic organophosphorus compounds such as pesticides and chemical warfare agents. …

A March 7, 2017 Lomonosov Moscow State University press release on EurekAlert, which originated the news item, describes the work in detail,

A group of scientists from the Faculty of Chemistry under the leadership of Prof. Alexander Kabanov has focused their research supported by a “megagrant” on the nanoparticle-based delivery to an organism of enzymes, capable of destroying toxic organophosphorous compounds. Development of first nanosized drugs has started more than 30 years ago and already in the 90-s first nanomedicines for cancer treatment entered the market. First such medicines were based on liposomes – spherical vesicles made of lipid bilayers. The new technology, developed by Kabanov and his colleagues, uses an enzyme, synthesized at the Lomonosov Moscow State University, encapsulated into a biodegradable polymer coat, based on an amino acid (glutamic acid).

Alexander Kabanov, Doctor of Chemistry, Professor at the Eshelman School of Pharmacy of the University of North Carolina (USA) and the Faculty of Chemistry, M. V. Lomonosov Moscow State University, one of the authors of the article explains: “At the end of the 80-s my team (at that time in Moscow) and independently Japanese colleagues led by Prof. Kazunori Kataoka from Tokyo began using polymer micelles for small molecules delivery. Soon the nanomedicine field has “exploded”. Currently hundreds of laboratories across the globe work in this area, applying a wide variety of approaches to creation of such nanosized agents. A medicine on the basis of polymeric micelles, developed by a Korean company Samyang Biopharm, was approved for human use in 2006.”

Professor Kabanov’s team after moving to the USA in 1994 focused on development of polymer micelles, which could include biopolymers due to electrostatic interactions. Initially chemists were interested in usage of micelles for RNA and DNA delivery but later on scientists started actively utilizing this approach for delivery of proteins and, namely, enzymes, to the brain and other organs.

Alexander Kabanov says: “At the time I worked at the University of Nebraska Medical Center, in Omaha (USA) and by 2010 we had a lot of results in this area. That’s why when my colleague from the Chemical Enzymology Department of the Lomonosov Moscow State University, Prof. Natalia Klyachko offered me to apply for a megagrant the research theme of the new laboratory was quite obvious. Specifically, to use our delivery approach, which we’ve called a “nanozyme”, for “improvement” of enzymes, developed by colleagues at the Lomonosov Moscow State University for its further medical application.”

Scientists together with the group of enzymologists from the Lomonosov Moscow State University under the leadership of Elena Efremenko, Doctor of Biological Sciences, have chosen organophosphorus hydrolase as a one of the delivered enzymes. Organophosphorus hydrolase is capable of degrading toxic pesticides and chemical warfare agents with very high rate. However, it has disadvantages: because of its bacterial origin, an immune response is observed as a result of its delivery to an organism of mammals. Moreover, organophosphorus hydrolase is quickly removed from the body. Chemists have solved this problem with the help of a “self-assembly” approach: as a result of inclusion of organophosphorus hydrolase enzyme in a nanozyme particles the immune response becomes weaker and, on the contrary, both the storage stability of the enzyme and its lifetime after delivery to an organism considerably increase. Rat experiments have proved that such nanozyme efficiently protects organisms against lethal doses of highly toxic pesticides and even chemical warfare agents, such as VX nerve gas.

Alexander Kabanov summarizes: “The simplicity of our approach is very important. You could get an organophosphorus hydrolase nanozyme by simple mixing of aqueous solutions of anenzyme and safe biocompatible polymer. This nanozyme is self-assembled due to electrostatic interaction between a protein (enzyme) and polymer”.

According to the scientist’s words the simplicity and technological effectiveness of the approach along with the obtained promising results of animal experiments bring hope that this modality could be successful and in clinical use.

Members of the Faculty of Chemistry of the Lomonosov Moscow State University, along with scientists from the 27th Central Research Institute of the Ministry of Defense of the Russian Federation, the Eshelman School of Pharmacy of the University of North Carolina at Chapel Hill (USA) and the University of Nebraska Medical Center (UNC) have taken part in the Project.

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

A simple and highly effective catalytic nanozyme scavenger for organophosphorus neurotoxins by Elena N. Efremenko, Ilya V. Lyagin, Natalia L. Klyachko, Tatiana Bronich, Natalia V. Zavyalova, Yuhang Jiang, Alexander V. Kabanov. Journal of Controlled Release Volume 247, 10 February 2017, Pages 175–181  http://dx.doi.org/10.1016/j.jconrel.2016.12.037

This paper is behind a paywall.

Hairy strength could lead to new body armour

A Jan. 18, 2017 news item on Nanowerk announces research into hair strength from the University of California at San Diego (UCSD or UC San Diego),

In a new study, researchers at the University of California San Diego investigate why hair is incredibly strong and resistant to breaking. The findings could lead to the development of new materials for body armor and help cosmetic manufacturers create better hair care products.

Hair has a strength to weight ratio comparable to steel. It can be stretched up to one and a half times its original length before breaking. “We wanted to understand the mechanism behind this extraordinary property,” said Yang (Daniel) Yu, a nanoengineering Ph.D. student at UC San Diego and the first author of the study.

A Jan. 18 (?), 2017 UCSD news release, which originated the news item, provides more information,

“Nature creates a variety of interesting materials and architectures in very ingenious ways. We’re interested in understanding the correlation between the structure and the properties of biological materials to develop synthetic materials and designs — based on nature — that have better performance than existing ones,” said Marc Meyers, a professor of mechanical engineering at the UC San Diego Jacobs School of Engineering and the lead author of the study.

In a study published online in Dec. in the journal Materials Science and Engineering C, researchers examined at the nanoscale level how a strand of human hair behaves when it is deformed, or stretched. The team found that hair behaves differently depending on how fast or slow it is stretched. The faster hair is stretched, the stronger it is. “Think of a highly viscous substance like honey,” Meyers explained. “If you deform it fast it becomes stiff, but if you deform it slowly it readily pours.”

Hair consists of two main parts — the cortex, which is made up of parallel fibrils, and the matrix, which has an amorphous (random) structure. The matrix is sensitive to the speed at which hair is deformed, while the cortex is not. The combination of these two components, Yu explained, is what gives hair the ability to withstand high stress and strain.

And as hair is stretched, its structure changes in a particular way. At the nanoscale, the cortex fibrils in hair are each made up of thousands of coiled spiral-shaped chains of molecules called alpha helix chains. As hair is deformed, the alpha helix chains uncoil and become pleated sheet structures known as beta sheets. This structural change allows hair to handle a large amount deformation without breaking.

This structural transformation is partially reversible. When hair is stretched under a small amount of strain, it can recover its original shape. Stretch it further, the structural transformation becomes irreversible. “This is the first time evidence for this transformation has been discovered,” Yu said.

“Hair is such a common material with many fascinating properties,” said Bin Wang, a UC San Diego PhD alumna from the Department of Mechanical and Aerospace Engineering and co-author on the paper. Wang is now at the Shenzhen Institutes of Advanced Technology in China continuing research on hair.

The team also conducted stretching tests on hair at different humidity levels and temperatures. At higher humidity levels, hair can withstand up to 70 to 80 percent deformation before breaking (dry hair can undergo up to 50 percent deformation). Water essentially “softens” hair — it enters the matrix and breaks the sulfur bonds connecting the filaments inside a strand of hair. Researchers also found that hair starts to undergo permanent damage at 60 degrees Celsius (140 degrees Fahrenheit). Beyond this temperature, hair breaks faster at lower stress and strain.

“Since I was a child I always wondered why hair is so strong. Now I know why,” said Wen Yang, a former postdoctoral researcher in Meyers’ research group and co-author on the paper.

The team is currently conducting further studies on the effects of water on the properties of human hair. Moving forward, the team is investigating the detailed mechanism of how washing hair causes it to return to its original shape.

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

Structure and mechanical behavior of human hair by Yang Yua, Wen Yang, Bin Wang, Marc André Meyers. Materials Science and Engineering: C Volume 73, 1 April 2017, Pages 152–163    http://dx.doi.org/10.1016/j.msec.2016.12.008

This paper is behind a paywall.

Solar-powered clothing

This research comes from the University of Central Florida (US) and includes a pop culture reference to the movie “Back to the Future.”  From a Nov. 14, 2016 news item on phys.org,

Marty McFly’s self-lacing Nikes in Back to the Future Part II inspired a UCF scientist who has developed filaments that harvest and store the sun’s energy—and can be woven into textiles.

The breakthrough would essentially turn jackets and other clothing into wearable, solar-powered batteries that never need to be plugged in. It could one day revolutionize wearable technology, helping everyone from soldiers who now carry heavy loads of batteries to a texting-addicted teen who could charge his smartphone by simply slipping it in a pocket.

A Nov. 14, 2016 University of Central Florida news release (also on EurekAlert) by Mark Schlueb, which originated the news item, expands on the theme,

“That movie was the motivation,” Associate Professor Jayan Thomas, a nanotechnology scientist at the University of Central Florida’s NanoScience Technology Center, said of the film released in 1989. “If you can develop self-charging clothes or textiles, you can realize those cinematic fantasies – that’s the cool thing.”

Thomas already has been lauded for earlier ground-breaking research. Last year, he received an R&D 100 Award – given to the top inventions of the year worldwide – for his development of a cable that can not only transmit energy like a normal cable but also store energy like a battery. He’s also working on semi-transparent solar cells that can be applied to windows, allowing some light to pass through while also harvesting solar power.

His new work builds on that research.

“The idea came to me: We make energy-storage devices and we make solar cells in the labs. Why not combine these two devices together?” Thomas said.

Thomas, who holds joint appointments in the College of Optics & Photonics and the Department of Materials Science & Engineering, set out to do just that.

Taking it further, he envisioned technology that could enable wearable tech. His research team developed filaments in the form of copper ribbons that are thin, flexible and lightweight. The ribbons have a solar cell on one side and energy-storing layers on the other.

Though more comfortable with advanced nanotechnology, Thomas and his team then bought a small, tabletop loom. After another UCF scientists taught them to use it, they wove the ribbons into a square of yarn.

The proof-of-concept shows that the filaments could be laced throughout jackets or other outwear to harvest and store energy to power phones, personal health sensors and other tech gadgets. It’s an advancement that overcomes the main shortcoming of solar cells: The energy they produce must flow into the power grid or be stored in a battery that limits their portability.

“A major application could be with our military,” Thomas said. “When you think about our soldiers in Iraq or Afghanistan, they’re walking in the sun. Some of them are carrying more than 30 pounds of batteries on their bodies. It is hard for the military to deliver batteries to these soldiers in this hostile environment. A garment like this can harvest and store energy at the same time if sunlight is available.”

There are a host of other potential uses, including electric cars that could generate and store energy whenever they’re in the sun.

“That’s the future. What we’ve done is demonstrate that it can be made,” Thomas said. “It’s going to be very useful for the general public and the military and many other applications.”

The proof-of-concept shows that the filaments could be laced throughout jackets or other outwear to harvest and store energy to power phones, personal health sensors and other tech gadgets. It's an advancement that overcomes the main shortcoming of solar cells: the energy they produce must flow into the power grid or be stored in a battery that limits their portability. Credit: UCF Read more at: http://phys.org/news/2016-11-future-solar-nanotech-powered.html#jCp

The proof-of-concept shows that the filaments could be laced throughout jackets or other outwear to harvest and store energy to power phones, personal health sensors and other tech gadgets. It’s an advancement that overcomes the main shortcoming of solar cells: the energy they produce must flow into the power grid or be stored in a battery that limits their portability. Credit: UCF

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

Wearable energy-smart ribbons for synchronous energy harvest and storage by Chao Li, Md. Monirul Islam, Julian Moore, Joseph Sleppy, Caleb Morrison, Konstantin Konstantinov, Shi Xue Dou, Chait Renduchintala, & Jayan Thomas. Nature Communications 7, Article number: 13319 (2016)  doi:10.1038/ncomms13319 Published online: 11 November 2016

This paper is open access.

Dexter Johnson in a Nov. 15, 2016 posting on his blog Nanoclast on the IEEE (Institute of Electrical and Electronics Engineers) provides context for this research and, in this excerpt, more insight from the researcher,

In a telephone interview with IEEE Spectrum, Thomas did concede that at this point, the supercapacitor was not capable of storing enough energy to replace the batteries entirely, but could be used to make a hybrid battery that would certainly reduce the load a soldier carries.

Thomas added: “By combining a few sets of ribbons (2-3 ribbons) in parallel and connecting these sets (3-4) in a series, it’s possible to provide enough power to operate a radio for 10 minutes. …

For anyone interested in knowing more about how this research fits into the field of textiles that harvest energy, I recommend reading Dexter’s piece.

Remembrance of things past

It’s Remembrance Day today (Nov. 11, 2016), a statutory holiday (in Canada) honouring the members of the military who have died and who have been injured in battle.

As for the survivors, our returning soldiers don’t have adequate support to reenter society after their tour of duty. Even more sadly, that has been true since time immemorial. The one hopeful aspect we have is increased awareness which will hopefully lead to needed changes.

Renata D’Aliesio, Les Perreaux and Allan Maki wrote a Nov. 4, 2016 article for the Globe and Mail about soldier suicide in Canada,

This article is part of The Unremembered, a Globe and Mail investigation into soldiers and veterans who died by suicide after deployment during the Afghanistan mission.

They were sons of bankers, miners and infanteers. They were strongmen and endurance runners. They were husbands and fathers who took their children camping and taught them how to play shinny on backyard rinks.

All 31 were dedicated Canadian soldiers and airmen who served on the perilous Afghanistan mission. They all came home. All ended their lives.

Most were haunted by the things they saw and did in Afghanistan, their families told The Globe and Mail. Many asked the military for help, but in several cases, their medical assessments and treatment were delayed, even as their post-traumatic stress, depression and sleeplessness worsened.

I believe there are issues with former peacekeepers; I’m thinking in particular of those who served in the Balkans and Rwanda, although I’m other certain missions could also be mentioned.

I grew up in a house with someone who had PTSD (post traumatic stress syndrome)—my father, a WWII veteran. It was difficult; he was difficult.  Only many years later did I realize what an extraordinary effort it must have taken for him to establish a family and relationships, go to work day in and day out, fight a battle with the bottle in his 40s, and come through the other side when he was in 70s, shortly before he died.

I once read this description of the process we all have to go through when soldiers return (the following is paraphrased),

There are two jobs to be accomplished. We have to forgive them (the soldiers) for what they’ve done and then, they have to forgive us for asking them to do it.

If I find anything about how to encourage the Canadian military to provide better support other than contacting your Member of Parliament, I will add it to this post.

One final remembrance of things past. Leonard Cohen died on Nov. 10, 2016. This Oct. 17, 2016 article by David Remnick seems quite timely (h/t Lainey Gossip Nov. 11, 2016 intro),

… Even before he had much of an audience, he had a distinct idea of the audience he wanted. In a letter to his publisher, he said that he was out to reach “inner-directed adolescents, lovers in all degrees of anguish, disappointed Platonists, pornography-peepers, hair-handed monks and Popists.”

I find it peculiarly appropriate to apply the description to soldiers.

Finally, here’s the song everyone has been playing in tribute to Cohen. This cover features a performance by the sublime K D Lang,

In Memoriam.

Protecting soldiers from biological and chemical agents with a ‘second skin’ made of carbon nanotubes

There are lots of ‘second skins’ which promise to protect against various chemical and biological agents, the big plus for this ‘skin’ from the US Lawrence Livermore National Laboratory is breathability. From an Aug. 3, 2016 news item on Nanowerk (Note: A link has been removed),

This material is the first key component of futuristic smart uniforms that also will respond to and protect from environmental chemical hazards. The research appears in the July 27 [2016] edition of the journal, , Advanced Materials (“Carbon Nanotubes: Ultrabreathable and Protective Membranes with Sub-5 nm Carbon Nanotube Pores”).

An Aug. 3, 2016 Lawrence Livermore National Laboratory (LLNL) news release (also on EurekAlert), which originated the news item, explains further (Note: Links have been removed),

High breathability is a critical requirement for protective clothing to prevent heat-stress and exhaustion when military personnel are engaged in missions in contaminated environments. Current protective military uniforms are based on heavyweight full-barrier protection or permeable adsorptive protective garments that cannot meet the critical demand of simultaneous high comfort and protection, and provide a passive rather than active response to an environmental threat.

The LLNL team fabricated flexible polymeric membranes with aligned carbon nanotube (CNT) channels as moisture conductive pores. The size of these pores (less than 5 nanometers, nm) is 5,000 times smaller than the width of a human hair [if 1 nm is 1/100,000 or 1/60,000 of a human hair {the two most commonly used measurements} then wouldn’t 5 nm be between 1/20,000 or1/15,000 of a human hair?] .

“We demonstrated that these membranes provide rates of water vapor transport that surpass those of commercial breathable fabrics like GoreTex, even though the CNT pores are only a few nanometers wide,” said Ngoc Bui, the lead author of the paper.

To provide high breathability, the new composite material takes advantage of the unique transport properties of carbon nanotube pores. By quantifying the membrane permeability to water vapor, the team found for the first time that, when a concentration gradient is used as a driving force, CNT nanochannels can sustain gas-transport rates exceeding that of a well-known diffusion theory by more than one order of magnitude.

These membranes also provide protection from biological agents due to their very small pore size — less than 5 nanometers (nm) wide. Biological threats like bacteria or viruses are much larger and typically more than 10-nm in size. Performed tests demonstrated that the CNT membranes repelled Dengue virus from aqueous solutions during filtration tests. This confirms that LLNL-developed CNT membranes provide effective protection from biological threats by size exclusion rather than by merely preventing wetting.

Furthermore, the results show that CNT pores combine high breathability and bio-protection in a single functional material.

However, chemical agents are much smaller in size and require the membrane pores to be able to react to block the threat. To encode the membrane with a smart and dynamic response to small chemical hazards, LLNL scientists and collaborators are surface modifying these prototype carbon nanotube membranes with chemical-threat-responsive functional groups. These functional groups will sense and block the threat like gatekeepers on the pore entrance. A second response scheme also is in development — similar to how living skin peels off when challenged with dangerous external factors. The fabric will exfoliate upon reaction with the chemical agent.

“The material will be like a smart second skin that responds to the environment,” said Kuang Jen Wu, leader of LLNL’s Biosecurity & Biosciences Group. “In this way, the fabric will be able to block chemical agents such as sulfur mustard (blister agent), GD and VX nerve agents, toxins such as staphylococcal enterotoxin and biological spores such as anthrax.”

Current work is directed toward designing this multifunctional material to undergo a rapid transition from the breathable state to the protective state.

“These responsive membranes are expected to be particularly effective in mitigating a physiological burden because a less breathable but protective state can be actuated locally and only when needed,” said Francesco Fornasiero, LLNL’s principal investigator of the project.

The new uniforms could be deployed in the field in less than 10 years.

“The goal of this science and technology program is to develop a focused, innovative technological solution for future chemical biological defense protective clothing,” said Tracee Whitfield, the DTRA [US Defense Threat Reduction Agency] science and technology manager for the Dynamic Multifunctional Material for a Second Skin Program. “Swatch-level evaluations will occur in early 2018 to demonstrate the concept of ‘second skin,’ a major milestone that is a key step in the maturation of this technology.”

The researchers have prepared a video describing their work,

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

Ultrabreathable and Protective Membranes with Sub-5 nm Carbon Nanotube Pores by Ngoc Bui, Eric R. Meshot, Sangil Kim, José Peña, Phillip W. Gibson, Kuang Jen Wu, and Francesco Fornasiero. Advanced Materials Volume 28, Issue 28, pages 5871–5877, July 27, 2016 DOI: 10.1002/adma.201600740 Version of Record online: 9 MAY 2016

© 2016 WILEY-VCH Verlag GmbH & Co. KGaA, Weinheim

This paper is behind a paywall.