Monthly Archives: June 2020

Smart film lets windows switch autonomously

This work from Korean research scientists gives me some hope that smart windows will one day be the norm. From a June 2, 2020 Korea Advanced Institute of Science and Technology (KAIST) press release (also on EurekAlert),

Researchers have developed a new easy-to-use smart optical film technology that allows smart window devices to autonomously switch between transparent and opaque states in response to the surrounding light conditions.

The proposed 3D hybrid nanocomposite film with a highly periodic network structure has empirically demonstrated its high speed and performance, enabling the smart window to quantify and self-regulate its high-contrast optical transmittance. As a proof of concept, a mobile-app-enabled smart window device for Internet of Things (IoT) applications has been realized using the proposed smart optical film with successful expansion to the 3-by-3-inch scale. This energy-efficient and cost-effective technology holds great promise for future use in various applications that require active optical transmission modulation.

Flexible optical transmission modulation technologies for smart applications including privacy-protection windows, zero-energy buildings, and beam projection screens have been in the spotlight in recent years. Conventional technologies that used external stimuli such as electricity, heat, or light to modulate optical transmission had only limited applications due to their slow response speeds, unnecessary color switching, and low durability, stability, and safety.

The optical transmission modulation contrast achieved by controlling the light scattering interfaces on non-periodic 2D surface structures that often have low optical density such as cracks, wrinkles, and pillars is also generally low. In addition, since the light scattering interfaces are exposed and not subject to any passivation, they can be vulnerable to external damage and may lose optical transmission modulation functions. Furthermore, in-plane scattering interfaces that randomly exist on the surface make large-area modulation with uniformity difficult.

Inspired by these limitations, a KAIST research team led by Professor Seokwoo Jeon from the Department of Materials Science and Engineering and Professor Jung-Wuk Hong of the Civil and Environmental Engineering Department used proximity-field nanopatterning (PnP) technology that effectively produces highly periodic 3D hybrid nanostructures, and an atomic layer deposition (ALD) technique that allows the precise control of oxide deposition and the high-quality fabrication of semiconductor devices.

The team then successfully produced a large-scale smart optical film with a size of 3 by 3 inches in which ultrathin alumina nanoshells are inserted between the elastomers in a periodic 3D nanonetwork.

This “mechano-responsive” 3D hybrid nanocomposite film with a highly periodic network structure is the largest smart optical transmission modulation film that exists. The film has been shown to have state-of-the-art optical transmission modulation of up to 74% at visible wavelengths from 90% initial transmission to 16% in the scattering state under strain. Its durability and stability were proved by more than 10,000 tests of harsh mechanical deformation including stretching, releasing, bending, and being placed under high temperatures of up to 70°C. When this film was used, the transmittance of the smart window device was adjusted promptly and automatically within one second in response to the surrounding light conditions. Through these experiments, the underlying physics of optical scattering phenomena occurring in the heterogeneous interfaces were identified. Their findings were reported in the online edition of Advanced Science on April 26 [2020]. KAIST Professor Jong-Hwa Shin’s group and Professor Young-Seok Shim at Silla University also collaborated on this project.

Donghwi Cho, a PhD candidate in materials science and engineering at KAIST and co-lead author of the study, said, “Our smart optical film technology can better control high-contrast optical transmittance by relatively simple operating principles and with low energy consumption and costs.”

“When this technology is applied by simply attaching the film to a conventional smart window glass surface without replacing the existing window system, fast switching and uniform tinting are possible while also securing durability, stability, and safety. In addition, its wide range of applications for stretchable or rollable devices such as wall-type displays for a beam projection screen will also fulfill aesthetic needs,” he added.

Here’s an image illustrating how the composite scatters light (I think),

Caption: Design concept of and fabrication procedures for the 3D scatterer. Credit: KAIST

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

High‐Contrast Optical Modulation from Strain‐Induced Nanogaps at 3D Heterogeneous Interfaces by Donghwi Cho, Prof. Young‐Seok Shim, Dr. Jae‐Wook Jung, Sang‐Hyeon Nam, Seokhwan Min, Dr. Sang‐Eon Lee, Youngjin Ham, Prof. Kwangjae Lee, Prof. Junyong Park, Prof. Jonghwa Shin, Prof. Jung‐Wuk Hong, and Prof. Seokwoo Jeon. Advanced Science DOI: First published: 26 April 2020

This paper is open access.

Antiviral, antibacterial surface for reducing spread of infectious diseases

In the past several years, scientists have created antibacterial surfaces by fabricating materials with specific types of nanostructures. According to a May 27, 2020 news item on Nanowerk, scientists have now been able to add antiviral properties (Note: A link has been removed),

The novel coronavirus pandemic has caused an increased demand for antimicrobial treatments that can keep surfaces clean, particularly in health care settings. Although some surfaces have been developed that can combat bacteria, what’s been lacking is a surface that can also kill off viruses.

Now, researchers have found a way to impart durable antiviral and antibacterial properties to an aluminum alloy used in hospitals, according to a report in ACS Biomaterials Science & Engineering (“Antiviral and Antibacterial Nanostructured Surfaces with Excellent Mechanical Properties for Hospital Applications”).

A May 27, 2020 American Chemical Society (ACS) news release (also on EurekAlert), which originated the news item, describes the problem and the proposed solution,

Among other mechanisms, viruses and bacteria can spread when a person touches a site where germs have settled, such as a doorframe, handrail or medical device. A healthy person can often fight off these bugs, but hospital patients can be more vulnerable to infection. The number of hospital-acquired infections has been on the decline in the U.S., but they still cause tens of thousands of deaths every year, according to the U.S. Department of Health and Human Services. Chemical disinfectants or coatings containing hydrophobic compounds, silver ions or copper can reduce infectious contaminants on surfaces, but these treatments don’t last. However, nature has developed its own solutions for battling microorganisms, including microscopic structural features that render some insect wings lethal to bacteria. Scientists have replicated this effect by forming surfaces covered with minute pillars and other shapes that distort and kill bacterial cells. But Prasad Yarlagadda and colleagues wanted to inactivate viruses as well as bacteria, so they set out to generate a novel nanoscale topography on long-lasting, industrially relevant materials.

The team experimented with disks of aluminum 6063, which is used in doorframes, window panels, and hospital and medical equipment. Etching the disks with sodium hydroxide for up to 3 hours changed the initially smooth, hydrophobic surface into a ridged, hydrophilic surface. Bacteria or viruses were then applied to the etched disks. Most of the Pseudomonas aeruginosa and Staphylococcus aureus bacteria were inactivated after 3 hours on the surface, while viability of common respiratory viruses dropped within 2 hours; both results were better than with plastic or smooth aluminum surfaces. The disks retained their effectiveness even after tests designed to mimic hospital wear and tear. The researchers note this is the first report to show combined antibacterial and antiviral properties of a durable, nanostructured surface that has the potential to stop the spread of infections arising from physical surfaces in hospitals. This strategy could be extended to surfaces in other public areas, such as cruise ships, planes and airports, they say. The team is now studying the effects of their nano-textured aluminum surfaces on the novel coronavirus.

This approach reminds me of Sharklet, a company fabricating a material designed to mimic a shark’s skin which is naturally antibacterial due to the nanostructures on its skin (see my September 18, 2014 posting).

More about Sharklet later. First, here’s a link to and a citation for the paper about this latest work,

Antiviral and Antibacterial Nanostructured Surfaces with Excellent Mechanical Properties for Hospital Applications by Jafar Hasan, Yanan Xu, Tejasri Yarlagadda, Michael Schuetz, Kirsten Spann, and Prasad KDV Yarlagadda. ACS Biomater. Sci. Eng. 2020, XXXX, XXX, XXX-XXX DOI: Publication Date:May 7, 2020 Copyright © 2020 American Chemical Society

This paper is behind a paywall.

Business and science: a Sharklet update

You can find the Sharklet website here. I wasn’t able to find any news about recent business deals other than the company’s acquisition by Peaceful Union in May 2017. From a May 17, 2017 Sharklet news release on Business Wire (and on the company website here),

Sharklet Technologies, Inc., a biotechnology company lauded for the creation and commercialization of Sharklet®, the world’s first micro-texture that inhibits bacterial growth on surfaces, has announced that it has completed a financing event led by Peaceful Union, an equity medical device firm in Hangzhou, China. Terms of the transaction were not disclosed.

The acquisition of the company will enable Sharklet Technologies to accelerate the development of Sharklet for medical devices where chemical-free bacterial inhibition is desired as well as high-touch surfaces prone to bacterial contamination. The company also will accelerate development of a newly enhanced wound dressing technology to encourage healing.

Joe Bagan and Mark Spiecker led the transaction structure. “This is an important day for the company and investors,” said Joe Bagan, former board chair, and Mark Spiecker, former CEO. “Our investors will realize a significant transaction while enabling the company to accelerate growth.”

In concert with the investment, Sharklet Technologies founding member, chief technology officer, and Sharklet inventor Dr. Anthony Brennan, will become chairman of the board assuming duties from chairman Joe Bagan and CEO Mark Spiecker.

Interestingly, Bagan and Spiecker are Chief Executive Officer (CEO) and President, respectively at STAQ Pharma. I wonder if there are plans to sell this company too.

Getting back to Sharklet, I found two items of recent origin about business but I cannot speak to the accuracy or trustworthiness of either item. That said, you will find they provide some detail about Sharklet’s new business directions and new business ties.

While Sharklet’s current business associations have a sketchy quality, it seems that’s not unusual in business, especially where new technologies are concerned. For example, the introduction of electricity into homes and businesses was a tumultuous affair as the 2008 book, ‘Power Struggles; Scientific Authority and the Creation of Practical Electricity Before Edison’ by Michael Brian Schiffer makes clear, from the MIT [Massachusetts Institute of Technology] Press ‘Power Struggles’ webpage,

In 1882, Thomas Edison and his Edison Electric Light Company unveiled the first large-scale electrical system in the world to light a stretch of offices in a city. … After laying out a unified theoretical framework for understanding technological change, Schiffer presents a series of fascinating case studies of pre-Edison electrical technologies, including Volta’s electrochemical battery, the blacksmith’s electric motor, the first mechanical generators, Morse’s telegraph, the Atlantic cable, and the lighting of the Capitol dome. Schiffer discusses claims of “practicality” and “impracticality” (sometimes hotly contested) made for these technologies, and examines the central role of the scientific authority—in particular, the activities of Joseph Henry, mid-nineteenth-century America’s foremost scientist—in determining the fate of particular technologies. These emerging electrical technologies formed the foundation of the modern industrial world. Schiffer shows how and why they became commercial products in the context of an evolving corporate capitalism in which conflicting judgments of practicality sometimes turned into power struggles. [emphases mine]

Even given that the book’s focus is pre-Edison electricity, how do you mention Edison himself without even casually mentioning Nikola Tesla and George Westinghouse in the book’s overview? Getting back to my point, emerging technologies do not emerge easily.

Space junk clogs up low-Earth orbit

Arianne Cohen’s May 28, 2020 article for Fast Company concisely sums up the space junk problem and solution (Note: A link has been removed),

Throwing money at problems works in space, too! A paper in the Proceedings of the National Academy of Sciences [PNAS] says that the space debris problem can be fixed once and for all, not by the engineers and scientists who consider space their domain, but with cold, hard cash: about $235,000 per satellite. Such a plan would create financial barriers for smaller organizations.

This looks pretty doesn’t it? hard to believe it’s a representation of the junk yard that floats around the earth.

Caption: A computer-generated image representing space debris as could be seen from high Earth orbit. The two main debris fields are the ring of objects in geosynchronous Earth orbit and the cloud of objects in low Earth orbit. Credit: NASA

For those who like a little more detail, a May 25, 2020 University of Colorado at Boulder news release (also on EurekAlert) presents the idea for orbital user fees as a means of limiting the amount of space junk,

Space is getting crowded. Aging satellites and space debris crowd low-Earth orbit, and launching new satellites adds to the collision risk. The most effective way to solve the space junk problem, according to a new study, is not to capture debris or deorbit old satellites: it’s an international agreement to charge operators “orbital-use fees” for every satellite put into orbit.

Orbital use fees would also increase the long-run value of the space industry, said economist Matthew Burgess, a CIRES [Cooperative Institute for Research in Environmental Sciences] Fellow and co-author of the new paper. By reducing future satellite and debris collision risk, an annual fee rising to about $235,000 per satellite would quadruple the value of the satellite industry by 2040, he and his colleagues concluded in a paper published today in the Proceedings of the National Academy of Sciences.

“Space is a common resource, but companies aren’t accounting for the cost their satellites impose on other operators when they decide whether or not to launch,” said Burgess, who is also an assistant professor in Environmental Studies and an affiliated faculty member in Economics at the University of Colorado Boulder. “We need a policy that lets satellite operators directly factor in the costs their launches impose on other operators.”

Currently, an estimated 20,000 objects–including satellites and space debris–are crowding low-Earth orbit. It’s the latest Tragedy of the Commons, the researchers said: Each operator launches more and more satellites until their private collision risk equals the value of the orbiting satellite.

So far, proposed solutions have been primarily technological or managerial, said Akhil Rao, assistant professor of economics at Middlebury College and the paper’s lead author. Technological fixes include removing space debris from orbit with nets, harpoons, or lasers. Deorbiting a satellite at the end of its life is a managerial fix.

Ultimately, engineering or managerial solutions like these won’t solve the debris problem because they don’t change the incentives for operators. For example, removing space debris might motivate operators to launch more satellites–further crowding low-Earth orbit, increasing collision risk, and raising costs. “This is an incentive problem more than an engineering problem. What’s key is getting the incentives right,” Rao said.

A better approach to the space debris problem, Rao and his colleagues found, is to implement an orbital-use fee–a tax on orbiting satellites. “That’s not the same as a launch fee,” Rao said, “Launch fees by themselves can’t induce operators to deorbit their satellites when necessary, and it’s not the launch but the orbiting satellite that causes the damage.”

Orbital-use fees could be straight-up fees or tradeable permits, and they could also be orbit-specific, since satellites in different orbits produce varying collision risks. Most important, the fee for each satellite would be calculated to reflect the cost to the industry of putting another satellite into orbit, including projected current and future costs of additional collision risk and space debris production–costs operators don’t currently factor into their launches. “In our model, what matters is that satellite operators are paying the cost of the collision risk imposed on other operators,” said Daniel Kaffine, professor of economics and RASEI Fellow at the University of Colorado Boulder and co-author on the paper.

And those fees would increase over time, to account for the rising value of cleaner orbits. In the researchers’ model, the optimal fee would rise at a rate of 14 percent per year, reaching roughly $235,000 per satellite-year by 2040.

For an orbital-use fee approach to work, the researchers found, all countries launching satellites would need to participate–that’s about a dozen that launch satellites on their own launch vehicles and more than 30 that own satellites. In addition, each country would need to charge the same fee per unit of collision risk for each satellite that goes into orbit, although each country could collect revenue separately. Countries use similar approaches already in carbon taxes and fisheries management.

In this study, Rao and his colleagues compared orbital-use fees to business as usual (that is, open access to space) and to technological fixes such as removing space debris. They found that orbital use fees forced operators to directly weigh the expected lifetime value of their satellites against the cost to industry of putting another satellite into orbit and creating additional risk. In other scenarios, operators still had incentive to race into space, hoping to extract some value before it got too crowded.

With orbital-use fees, the long-run value of the satellite industry would increase from around $600 billion under the business-as-usual scenario to around $3 trillion, researchers found. The increase in value comes from reducing collisions and collision-related costs, such as launching replacement satellites.

Orbital-use fees could also help satellite operators get ahead of the space junk problem. “In other sectors, addressing the Tragedy of the Commons has often been a game of catch-up with substantial social costs. But the relatively young space industry can avoid these costs before they escalate,” Burgess said.

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

Orbital-use fees could more than quadruple the value of the space industry by Akhil Rao, Matthew G. Burgess, and Daniel Kaffine. DOI: PNAS first published May 26, 2020

This paper is behind a paywall.

Clean up oil spills with a smart sponge?

I love the part with the magnet,

All of the main points are made in the video but for those who like text, there’s a May 28, 2020 news item on describing this new smart sponge for cleaning up oil spills (Note: Links have been removed),

A Northwestern University-led [Chicago, Illinois, US] team has developed a highly porous smart sponge that selectively soaks up oil in water.

With an ability to absorb more than 30 times its weight in oil, the sponge could be used to inexpensively and efficiently clean up oil spills without harming marine life. After squeezing the oil out of the sponge, it can be reused many dozens of times without losing its effectiveness.

“Oil spills have devastating and immediate effects on the environment, human health and economy,” said Northwestern’s Vinayak Dravid, who led the research. “Although many spills are small and may not make the evening news, they are still profoundly invasive to the ecosystem and surrounding community. Our sponge can remediate these spills in a more economic, efficient and eco-friendly manner than any of the current state-of-the-art solutions.”

A May 28, 2020 Northwestern University news release (also on EurekAlert), which originated the news item, reveals (as did the video) the characteristics that make this smart sponge particularly interesting,

Oil spill clean-up is an expensive and complicated process that often harms marine life and further damages the environment. Currently used solutions include burning the oil, using chemical dispersants to breakdown oil into very small droplets, skimming oil floating on top of water and/or absorbing it with expensive, unrecyclable sorbents.

“Each approach has its own drawbacks and none are sustainable solutions,” Nandwana [Vikas Nandwana, a senior research associate in Dravid’s laboratory] said. “Burning increases carbon emissions and dispersants are terribly harmful for marine wildlife. Skimmers don’t work in rough waters or with thin layers of oil. And sorbents are not only expensive, but they generate a huge amount of physical waste — similar to the diaper landfill issue.”

The Northwestern solution bypasses these challenges by selectively absorbing oil and leaving clean water and unaffected marine life behind. The secret lies in a nanocomposite coating of magnetic nanostructures and a carbon-based substrate that is oleophilic (attracts oil), hydrophobic (resists water) and magnetic. The nanocomposite’s nanoporous 3D structure selectively interacts with and binds to the oil molecules, capturing and storing the oil until it is squeezed out. The magnetic nanostructures give the smart sponge two additional functionalities: controlled movement in the presence of an external magnetic field and desorption of adsorbed components, such as oil, in a simulated and remote manner.

The OHM (oleophilic hydrophobic magnetic) nanocomposite slurry can be used to coat any cheap, commercially available sponge. The researchers applied a thin coating of the slurry to the sponge, squeezed out the excess and let it dry. The sponge is quickly and easily converted into a smart sponge (or “OHM sponge”) with a selective affinity for oil.

Vinayak and his team tested the OHM sponge with many different types of crude oils of varying density and viscosity. The OHM sponge consistently absorbed up to 30 times its weight in oil, leaving the water behind. To mimic natural waves, researchers put the OHM sponge on a shaker submerged in water. Even after vigorous shaking, the sponge release less than 1% of its absorbed oil back into the water.

“Our sponge works effectively in diverse and extreme aquatic conditions that have different pH and salinity levels,” Dravid said. “We believe we can address a giga-ton problem with a nanoscale solution.”

“We are excited to introduce such smart sponges as an environmental remediation platform for selectively removing and recovering pollutants present in water, soil and air, such as excess nutrients, heavy metal contaminants, VOC/toxins and others,” Nandwana said. “The nanostructure coating can be tailored to selectively adsorb (and later desorb) these pollutants.”

The team also is working on another grade of OHM sponge that can selectively absorb (and later recover) excess dissolved nutrients, such as phosphates, from fertilizer runoff and agricultural pollution. Stephanie Ribet, a Ph.D. candidate in Dravid’s lab and paper coauthor is pursuing this topic. The team plans to develop and commercialize OHM technology for environmental clean-up.

Bravo to professor Vinayak Dravid and his team. I’m sure I’m not alone in wishing you and your team the best of luck as you continue to develop this remediation technology.

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

OHM Sponge: A Versatile, Efficient, and Ecofriendly Environmental Remediation Platform by Vikas Nandwana, Stephanie M. Ribet, Roberto D. Reis, Yuyao Kuang, Yash More, and Vinayak P. Dravid. Ind. Eng. Chem. Res. 2020, XXXX, XXX, XXX-XXX DOI: Publication Date:May 12, 2020 Copyright © 2020 American Chemical Society

This paper is behind a paywall.

Tiny sponges lure coronavirus away from lung cells

This research approach looks promising as three news releases trumpeting the possibilities indicate. First, there’s the June 17, 2020 American Chemical Society (ACS) news release,

Scientists are working overtime to find an effective treatment for COVID-19, the illness caused by the new coronavirus, SARS-CoV-2. Many of these efforts target a specific part of the virus, such as the spike protein. Now, researchers reporting in Nano Letters have taken a different approach, using nanosponges coated with human cell membranes –– the natural targets of the virus –– to soak up SARS-CoV-2 and keep it from infecting cells in a petri dish.

To gain entry, SARS-CoV-2 uses its spike protein to bind to two known proteins on human cells, called ACE2 and CD147. Blocking these interactions would keep the virus from infecting cells, so many researchers are trying to identify drugs directed against the spike protein. Anthony Griffiths, Liangfang Zhang and colleagues had a different idea: making a nanoparticle decoy with the virus’ natural targets, including ACE2 and CD147, to lure SARS-CoV-2 away from cells. And to test this idea, they conducted experiments with the actual SARS-CoV-2 virus in a biosafety level 4 lab.

The researchers coated a nanoparticle polymer core with cell membranes from either human lung epithelial cells or macrophages –– two cell types infected by SARS-CoV-2. They showed that the nanosponges had ACE2 and CD147, as well as other cell membrane proteins, projecting outward from the polymer core. When administered to mice, the nanosponges did not show any short-term toxicity. Then, the researchers treated cells in a dish with SARS-CoV-2 and the lung epithelial or macrophage nanosponges. Both decoys neutralized SARS-CoV-2 and prevented it from infecting cells to a similar extent. The researchers plan to next test the nanosponges in animals before moving to human clinical trials. In theory, the nanosponge approach would work even if SARS-CoV-2 mutates to resist other therapies, and it could be used against other viruses, as well, the researchers say.

In this illustration, a nanosponge coated with a human cell membrane acts as a decoy to prevent a virus from entering cells. Credit: Adapted from Nano Letters 2020, DOI: 10.1021/acs.nanolett.0c02278

There are two research teams involved, one at Boston University and the other at the University of California at San Diego (UC San Diego or UCSD). The June 18, 2020 Boston University news release (also on EurekAlert) by Kat J. McAlpine adds more details about the research, provides some insights from the researchers, and is a little redundant if you’ve already seen the ACS news release,

Imagine if scientists could stop the coronavirus infection in its tracks simply by diverting its attention away from living lung cells? A new therapeutic countermeasure, announced in a Nano Letters study by researchers from Boston University’s National Emerging Infectious Diseases Laboratories (NEIDL) and the University of California San Diego, appears to do just that in experiments that were carried out at the NEIDL in Boston.

The breakthrough technology could have major implications for fighting the SARS-CoV-2 virus responsible for the global pandemic that’s already claimed nearly 450,000 lives and infected more than 8 million people. But, perhaps even more significantly, it has the potential to be adapted to combat virtually any virus, such as influenza or even Ebola.

“I was skeptical at the beginning because it seemed too good to be true,” says NEIDL microbiologist Anna Honko, one of the co-first authors on the study. “But when I saw the first set of results in the lab, I was just astonished.”

The technology consists of very small, nanosized drops of polymers–essentially, soft biofriendly plastics–covered in fragments of living lung cell and immune cell membranes.

“It looks like a nanoparticle coated in pieces of cell membrane,” Honko says. “The small polymer [droplet] mimics a cell having a membrane around it.”

The SARS-CoV-2 virus seeks out unique signatures of lung cell membranes and latches onto them. When that happens inside the human body, the coronavirus infection takes hold, with the SARS-CoV-2 viruses hijacking lung cells to replicate their own genetic material. But in experiments at the NEIDL, BU researchers observed that polymer droplets laden with pieces of lung cell membrane did a better job of attracting the SARS-CoV-2 virus than living lung cells. [emphasis mine]

By fusing with the SARS-CoV-2 virus better than living cells can, the nanotechnology appears to be an effective countermeasure to coronavirus infection, preventing SARS-CoV-2 from attacking cells.

“Our guess is that it acts like a decoy, it competes with cells for the virus,” says NEIDL microbiologist Anthony Griffiths, co-corresponding author on the study. “They are little bits of plastic, just containing the outer pieces of cells with none of the internal cellular machinery contained inside living cells. Conceptually, it’s such a simple idea. It mops up the virus like a sponge.”

That attribute is why the UC San Diego and BU research team call the technology “nanosponges.” Once SARS-CoV-2 binds with the cell fragments inside a nanosponge droplet–each one a thousand times smaller than the width of a human hair–the coronavirus dies. Although the initial results are based on experiments conducted in cell culture dishes, the researchers believe that inside a human body, the biodegradable nanosponges and the SARS-CoV-2 virus trapped inside them could then be disposed of by the body’s immune system. The immune system routinely breaks down and gets rid of dead cell fragments caused by infection or normal cell life cycles.

There is also another important effect that the nanosponges have in the context of coronavirus infection. Honko says nanosponges containing fragments of immune cells can soak up cellular signals that increase inflammation [emphases mine]. Acute respiratory distress, caused by an inflammatory cascade inside the lungs, is the most deadly aspect of the coronavirus infection, sending patients into the intensive care unit for oxygen or ventilator support to help them breathe.

But the nanosponges, which can attract the inflammatory molecules that send the immune system into dangerous overdrive, can help tamp down that response, Honko says. By using both kinds of nanosponges, some containing lung cell fragments and some containing pieces of immune cells, she says it’s possible to “attack the coronavirus and the [body’s] response” responsible for disease and eventual lung failure.

At the NEIDL, Honko and Griffiths are now planning additional experiments to see how well the nanosponges can prevent coronavirus infection in animal models of the disease. They plan to work closely with the team of engineers at UC San Diego, who first developed the nanosponges more than a decade ago, to tailor the technology for eventual safe and effective use in humans.

“Traditionally, drug developers for infectious diseases dive deep on the details of the pathogen in order to find druggable targets,” said Liangfang Zhang, a UC San Diego nanoengineer and leader of the California-based team, according to a UC San Diego press release. “Our approach is different. We only need to know what the target cells are. And then we aim to protect the targets by creating biomimetic decoys.”

When the novel coronavirus first appeared, the idea of using the nanosponges to combat the infection came to Zhang almost immediately. He reached out to the NEIDL for help. Looking ahead, the BU and UC San Diego collaborators believe the nanosponges can easily be converted into a noninvasive treatment.

“We should be able to drop it right into the nose,” Griffiths says. “In humans, it could be something like a nasal spray.”

Honko agrees: “That would be an easy and safe administration method that should target the appropriate [respiratory] tissues. And if you wanted to treat patients that are already intubated, you could deliver it straight into the lung.”

Griffiths and Honko are especially intrigued by the nanosponges as a new platform for treating all types of viral infections. “The broad spectrum aspect of this is exceptionally appealing,” Griffiths says. The researchers say the nanosponge could be easily adapted to house other types of cell membranes preferred by other viruses, creating many new opportunities to use the technology against other tough-to-treat infections like the flu and even deadly hemorrhagic fevers caused by Ebola, Marburg, or Lassa viruses.

“I’m interested in seeing how far we can push this technology,” Honko says.

The University of California as San Diego has released a video illustrating the nanosponges work,

There’s also this June 17, 2020 University of California at San Diego (UC San Diego) news release (also on EurekAlert) by Ioana Patringenaru, which offers extensive new detail along with, if you’ve read one or both of the news releases in the above, a few redundant bits,

Nanoparticles cloaked in human lung cell membranes and human immune cell membranes can attract and neutralize the SARS-CoV-2 virus in cell culture, causing the virus to lose its ability to hijack host cells and reproduce.

The first data describing this new direction for fighting COVID-19 were published on June 17 in the journal Nano Letters. The “nanosponges” were developed by engineers at the University of California San Diego and tested by researchers at Boston University.

The UC San Diego researchers call their nano-scale particles “nanosponges” because they soak up harmful pathogens and toxins.

In lab experiments, both the lung cell and immune cell types of nanosponges caused the SARS-CoV-2 virus to lose nearly 90% of its “viral infectivity” in a dose-dependent manner. Viral infectivity is a measure of the ability of the virus to enter the host cell and exploit its resources to replicate and produce additional infectious viral particles.

Instead of targeting the virus itself, these nanosponges are designed to protect the healthy cells the virus invades.

“Traditionally, drug developers for infectious diseases dive deep on the details of the pathogen in order to find druggable targets. Our approach is different. We only need to know what the target cells are. And then we aim to protect the targets by creating biomimetic decoys,” said Liangfang Zhang, a nanoengineering professor at the UC San Diego Jacobs School of Engineering.

His lab first created this biomimetic nanosponge platform more than a decade ago and has been developing it for a wide range of applications ever since [emphasis mine]. When the novel coronavirus appeared, the idea of using the nanosponge platform to fight it came to Zhang “almost immediately,” he said.

In addition to the encouraging data on neutralizing the virus in cell culture, the researchers note that nanosponges cloaked with fragments of the outer membranes of macrophages could have an added benefit: soaking up inflammatory cytokine proteins, which are implicated in some of the most dangerous aspects of COVID-19 and are driven by immune response to the infection.

Making and testing COVID-19 nanosponges

Each COVID-19 nanosponge–a thousand times smaller than the width of a human hair–consists of a polymer core coated in cell membranes extracted from either lung epithelial type II cells or macrophage cells. The membranes cover the sponges with all the same protein receptors as the cells they impersonate–and this inherently includes whatever receptors SARS-CoV-2 uses to enter cells in the body.

The researchers prepared several different concentrations of nanosponges in solution to test against the novel coronavirus. To test the ability of the nanosponges to block SARS-CoV-2 infectivity, the UC San Diego researchers turned to a team at Boston University’s National Emerging Infectious Diseases Laboratories (NEIDL) to perform independent tests. In this BSL-4 lab–the highest biosafety level for a research facility–the researchers, led by Anthony Griffiths, associate professor of microbiology at Boston University School of Medicine, tested the ability of various concentrations of each nanosponge type to reduce the infectivity of live SARS-CoV-2 virus–the same strains that are being tested in other COVID-19 therapeutic and vaccine research.

At a concentration of 5 milligrams per milliliter, the lung cell membrane-cloaked sponges inhibited 93% of the viral infectivity of SARS-CoV-2. The macrophage-cloaked sponges inhibited 88% of the viral infectivity of SARS-CoV-2. Viral infectivity is a measure of the ability of the virus to enter the host cell and exploit its resources to replicate and produce additional infectious viral particles.

“From the perspective of an immunologist and virologist, the nanosponge platform was immediately appealing as a potential antiviral because of its ability to work against viruses of any kind. This means that as opposed to a drug or antibody that might very specifically block SARS-CoV-2 infection or replication, these cell membrane nanosponges might function in a more holistic manner in treating a broad spectrum of viral infectious diseases. I was optimistically skeptical initially that it would work, and then thrilled once I saw the results and it sunk in what this could mean for therapeutic development as a whole,” said Anna Honko, a co-first author on the paper and a Research Associate Professor, Microbiology at Boston University’s National Emerging Infectious Diseases Laboratories (NEIDL).

In the next few months, the UC San Diego researchers and collaborators will evaluate the nanosponges’ efficacy in animal models. The UC San Diego team has already shown short-term safety in the respiratory tracts and lungs of mice. If and when these COVID-19 nanosponges will be tested in humans depends on a variety of factors, but the researchers are moving as fast as possible.

“Another interesting aspect of our approach is that even as SARS-CoV-2 mutates, as long as the virus can still invade the cells we are mimicking, our nanosponge approach should still work. I’m not sure this can be said for some of the vaccines and therapeutics that are currently being developed,” said Zhang.

The researchers also expect these nanosponges would work against any new coronavirus or even other respiratory viruses, including whatever virus might trigger the next respiratory pandemic.

Mimicking lung epithelial cells and immune cells

Since the novel coronavirus often infects lung epithelial cells as the first step in COVID-19 infection, Zhang and his colleagues reasoned that it would make sense to cloak a nanoparticle in fragments of the outer membranes of lung epithelial cells to see if the virus could be tricked into latching on it instead of a lung cell.

Macrophages, which are white blood cells that play a major role in inflammation, also are very active in the lung during the course of a COVID-19 illness, so Zhang and colleagues created a second sponge cloaked in macrophage membrane.

The research team plans to study whether the macrophage sponges also have the ability to quiet cytokine storms in COVID-19 patients.

“We will see if the macrophage nanosponges can neutralize the excessive amount of these cytokines as well as neutralize the virus,” said Zhang.

Using macrophage cell fragments as cloaks builds on years of work to develop therapies for sepsis using macrophage nanosponges.

In a paper published in 2017 in Proceedings of the National Academy of Sciences, Zhang and a team of researchers at UC San Diego showed that macrophage nanosponges can safely neutralize both endotoxins and pro-inflammatory cytokines in the bloodstream of mice. A San Diego biotechnology company co-founded by Zhang called Cellics Therapeutics is working to translate this macrophage nanosponge work into the clinic.

A potential COVID-19 therapeutic The COVID-19 nanosponge platform has significant testing ahead of it before scientists know whether it would be a safe and effective therapy against the virus in humans, Zhang cautioned [emphasis mine]. But if the sponges reach the clinical trial stage, there are multiple potential ways of delivering the therapy that include direct delivery into the lung for intubated patients, via an inhaler like for asthmatic patients, or intravenously, especially to treat the complication of cytokine storm.

A therapeutic dose of nanosponges might flood the lung with a trillion or more tiny nanosponges that could draw the virus away from healthy cells. Once the virus binds with a sponge, “it loses its viability and is not infective anymore, and will be taken up by our own immune cells and digested,” said Zhang.

“I see potential for a preventive treatment, for a therapeutic that could be given early because once the nanosponges get in the lung, they can stay in the lung for some time,” Zhang said. “If a virus comes, it could be blocked if there are nanosponges waiting for it.”

Growing momentum for nanosponges

Zhang’s lab at UC San Diego created the first membrane-cloaked nanoparticles over a decade ago. The first of these nanosponges were cloaked with fragments of red blood cell membranes. These nanosponges are being developed to treat bacterial pneumonia and have undergone all stages of pre-clinical testing by Cellics Therapeutics, the San Diego startup cofounded by Zhang. The company is currently in the process of submitting the investigational new drug (IND) application to the FDA for their lead candidate: red blood cell nanosponges for the treatment of methicillin-resistant staphylococcus aureus (MRSA) pneumonia. The company estimates the first patients in a clinical trial will be dosed next year.

The UC San Diego researchers have also shown that nanosponges can deliver drugs to a wound site; sop up bacterial toxins that trigger sepsis; and intercept HIV before it can infect human T cells.

The basic construction for each of these nanosponges is the same: a biodegradable, FDA-approved polymer core is coated in a specific type of cell membrane, so that it might be disguised as a red blood cell, or an immune T cell or a platelet cell. The cloaking keeps the immune system from spotting and attacking the particles as dangerous invaders.

“I think of the cell membrane fragments as the active ingredients. This is a different way of looking at drug development,” said Zhang. “For COVID-19, I hope other teams come up with safe and effective therapies and vaccines as soon as possible. At the same time, we are working and planning as if the world is counting on us.”

I wish the researchers good luck. For the curious, here’s a link to and a citation for the paper,

Cellular Nanosponges Inhibit SARS-CoV-2 Infectivity by Qiangzhe Zhang, Anna Honko, Jiarong Zhou, Hua Gong, Sierra N. Downs, Jhonatan Henao Vasquez, Ronnie H. Fang, Weiwei Gao, Anthony Griffiths, and Liangfang Zhang. Nano Lett. 2020, XXXX, XXX, XXX-XXX DOI: Publication Date:June 17, 2020 Copyright © 2020 American Chemical Society

This paper appears to be open access.

Here, too, is the Cellics Therapeutics website.

Sunscreens 2020 and the Environmental Working Group (EWG)

There must be some sweet satisfaction or perhaps it’s better described as relief for the Environmental Working Group (EWG) now that sunscreens with metallic (zinc oxide and/or titanium dioxide) nanoparticles are gaining wide acceptance. (More about the history and politics EWG and metallic nanoparticles at the end of this posting.)

This acceptance has happened alongside growing concerns about oxybenzone, a sunscreen ingredient that EWG has long warned against. Oxybenzone has been banned from use in Hawaii due to environmental concerns (see my July 6, 2018 posting; scroll down about 40% of the way for specifics about Hawaii). Also, it is one of the common sunscreen ingredients for which the US Food and Drug Administration (FDA) is completing a safety review.

Today, zinc oxide and titanium dioxide metallic nanoparticles are being called minerals, as in, “mineral-based” sunscreens. They are categorized as physical sunscreens as opposed to chemical sunscreens.

I believe the most recent sunscreen posting here was my 2018 update (uly 6, 2018 posting) so the topic is overdue for some attention here. From a May 21, 2020 EWG news release (received via email),

As states reopen and Americans leave their homes to venture outside, it’s important for them to remember to protect their skin from the sun’s harmful rays. Today the Environmental Working Group released its 14th annual Guide to Sunscreens.  

This year researchers rated the safety and efficacy of more than 1,300 SPF products – including sunscreens, moisturizers and lip balms – and found that only 25 percent offer adequate protection and do not contain worrisome ingredients such as oxybenzone, a potential hormone-disrupting chemical that is readily absorbed by the body.

Despite a delay in finalizing rules that would make all sunscreens on U.S. store shelves safer, the Food and Drug Administration, the agency that governs sunscreen safety, is completing tests that highlight concerns with common sunscreen ingredients. Last year, the agency published two studies showing that, with just a single application, six commonly used chemical active ingredients, including oxybenzone, are readily absorbed through the skin and could be detected in our bodies at levels that could cause harm.

“It’s quite concerning,” said Nneka Leiba, EWG’s vice president of Healthy Living science. “Those studies don’t prove whether the sunscreens are unsafe, but they do highlight problems with how these products are regulated.”

“EWG has been advocating for the FDA to review these chemical ingredients for 14 years,” Leiba said. “We slather these ingredients on our skin, but these chemicals haven’t been adequately tested. This is just one example of the backward nature of product regulation in the U.S.”

Oxybenzone remains a commonly used active ingredient, found in more than 40 percent of the non-mineral sunscreens in this year’s guide. Oxybenzone is allergenic and a potential endocrine disruptor, and has been detected in human breast milk, amniotic fluid, urine and blood.

According to EWG’s assessment, fewer than half of the products in this year’s guide contain active ingredients that the FDA has proposed are safe and effective.

“Based on the best current science and toxicology data, we continue to recommend sunscreens with the mineral active ingredients zinc dioxide and titanium dioxide, because they are the only two ingredients the FDA recognized as safe or effective in their proposed draft rules,” said Carla Burns, an EWG research and database analyst who manages the updates to the sunscreen guide.

Most people select sunscreen products based on their SPF, or sunburn protection factor, and mistakenly assume that bigger numbers offer better protection. According to the FDA, higher SPF values have not been shown to provide additional clinical benefit and may give users a false sense of protection. This may lead to overexposure to UVA rays that increase the risk of long-term skin damage and cancer. The FDA has proposed limiting SPF claims to 60+.

EWG continues to hone our recommendations by strengthening the criteria for assessing sunscreens, which are based on the latest findings in the scientific literature and commissioned tests of sunscreen product efficacy. This year EWG made changes to our methodology in order to strengthen our requirement that products provide the highest level of UVA protection.

“Our understanding of the dangers associated with UVA exposure is increasing, and they are of great concern,” said Burns. “Sunburn during early life, especially childhood, is very dangerous and a risk factor for all skin cancers, but especially melanoma. Babies and young children are especially vulnerable to sun damage. Just a few blistering sunburns early in life can double a person’s risk of developing melanoma later in life.”

EWG researchers found 180 sunscreens that meet our criteria for safety and efficacy and would likely meet the proposed FDA standards. Even the biggest brands now provide mineral options for consumers.  

Even for Americans continuing to follow stay-at-home orders, wearing an SPF product may still be important. If you’re sitting by a window, UVA and UVB rays can penetrate the glass.  

It is important to remember that sunscreen is only one part of a sun safety routine. People should also protect their skin by covering up with clothing, hats and sunglasses. And sunscreen must be reapplied at least every two hours to stay effective.

EWG’s Guide to Sunscreens helps consumers find products that get high ratings for providing adequate broad-spectrum protection and that are made with ingredients that pose fewer health concerns.

The new guide also includes lists of:

Here are more quick tips for choosing better sunscreens:

  • Check your products in EWG’s sunscreen database and avoid those with harmful ingredients.
  • Avoid products with oxybenzone. This chemical penetrates the skin, gets into the bloodstream and can affect normal hormone activities.
  • Steer clear of products with SPF higher than 50+. High SPF values do not necessarily provide increased UVA protection and may fool you into thinking you are safe from sun damage.
  • Avoid sprays. These popular products pose inhalation concerns, and they may not provide a thick and uniform coating on the skin.
  • Stay away from retinyl palmitate. Government studies link the use of retinyl palmitate, a form of vitamin A, to the formation of skin tumors and lesions when it is applied to sun-exposed skin.
  • Avoid intense sun exposure during the peak hours of 10 a.m. to 4 p.m.

Shoppers on the go can download EWG’s Healthy Living app to get ratings and safety information on sunscreens and other personal care products. Also be sure to check out EWG’s sunscreen label decoder.

One caveat, these EWG-recommended products might not be found in Canadian stores or your favourite product may not have been reviewed for inclusion, as a product to be sought out or avoided, in their database. For example, I use a sunscreen that isn’t listed in the database, although at least a few other of the company’s sunscreen products are. On the plus side, my sunscreen doesn’t include oxybenzone or retinyl palmitate as ingredients.

To sum up the situation with sunscreens containing metallic nanoparticles (minerals), they are considered to be relatively safe but should new research emerge that designation could change. In effect, all we can do is our best with the information at hand.

History and politics of metallic nanoparticles in sunscreens

In 2009 it was a bit of a shock when the EWG released a report recommending the use of sunscreens with metallic nanoparticles in the list of ingredients. From my July 9, 2009 posting,

The EWG (Environmental Working Group) is, according to Maynard [as of 20202: Dr. Andrew Maynard is a scientist and author, Associate Director of Faculty in the ASU {Arizona State University} School for the Future of Innovation in Society, also the director of the ASU Risk Innovation Lab, and leader of the Risk Innovation Nexus], not usually friendly to industry and they had this to say about their own predisposition prior to reviewing the data (from EWG),

When we began our sunscreen investigation at the Environmental Working Group, our researchers thought we would ultimately recommend against micronized and nano-sized zinc oxide and titanium dioxide sunscreens. After all, no one has taken a more expansive and critical look than EWG at the use of nanoparticles in cosmetics and sunscreens, including the lack of definitive safety data and consumer information on these common new ingredients, and few substances more dramatically highlight gaps in our system of public health protections than the raw materials used in the burgeoning field of nanotechnology. But many months and nearly 400 peer-reviewed studies later, we find ourselves drawing a different conclusion, and recommending some sunscreens that may contain nano-sized ingredients.

My understanding is that after this report, the EWG was somewhat ostracized by collegial organizations. Friends of the Earth (FoE) and the ETC Group both of which issued reports that were published after the EWG report and were highly critical of ‘nano sunscreens’.

The ETC Group did not continue its anti nanosunscreen campaign for long (I saw only one report) but FoE (in particular the Australian arm of the organization) more than made up for that withdrawal and to sad effect. My February 9, 2012 post title was this: Unintended consequences: Australians not using sunscreens to avoid nanoparticles?

An Australian government survey found that 13% of Australians were not using any sunscreen due to fears about nanoparticles. In a country with the highest incidence of skin cancer in the world and, which spent untold millions over decades getting people to cover up in the sun, it was devastating news.

FoE immediately withdrew all their anti nanosunscreen materials in Australia from circulation while firing broadsides at the government. The organization’s focus on sunscreens with metallic nanoparticles has diminished since 2012.


I have difficulty trusting materials from FoE and you can see why here in this July 26, 2011 posting (Misunderstanding the data or a failure to research? Georgia Straight article about nanoparticles). In it, I analyze Alex Roslin’s profoundly problematic article about metallic nanoparticles and other engineered nanoparticles. All of Roslin’s article was based on research and materials produced by FoE which misrepresented some of the research. Roslin would have realized that if he had bothered to do any research for himself.

EWG impressed me mightily with their refusal to set aside or dismiss the research disputing their initial assumption that metallic nanoparticles in sunscreens were hazardous. (BTW, there is one instance where metallic nanoparticles in sunscreens are of concern. My October 13, 2013 posting about anatase and rutile forms of titanium dioxide at the nanoscale features research on that issue.)

EWG’s Wikipedia entry

Whoever and however many are maintaining this page, they don’t like EWG at all,

The accuracy of EWG reports and statements have been criticized, as has its funding by the organic food industry[2][3][4][5] Its warnings have been labeled “alarmist”, “scaremongering” and “misleading”.[6][7][8] Despite the questionable status of its work, EWG has been influential.[9]

This is the third paragraph in the Introduction. At its very best, the information is neutral, otherwise, it’s much like that third paragraph.

Even John D. Rockeller’s entry is more flattering and he was known as the ‘most hated man in America’ as this show description on the Public Broadcasting Service (PBS) website makes clear,

American Experience

The Rockefellers Chapter One

Clip: Season 13 Episode 1 | 9m 37s

John D. Rockefeller was the world’s first billionaire and the most hated man in America. Watch the epic story of the man who monopolized oil.

Fun in the sun

Have fun in the sun this summer. There’s EWG’s sunscreen database, the tips listed in the news release, and EWG also has a webpage where they describe their methodology for how they assess sunscreens. It gets a little technical (for me anyway) but it should answer any further safety questions you might have after reading this post.

It may require a bit of ingenuity given the concerns over COVID-19 but I’m constantly amazed at the inventiveness with which so many people have met this pandemic. (This June 15, 2020 Canadian Broadcasting Corporation article by Sheena Goodyear features a family that created a machine that won the 2020 Rube Goldberg Bar of Soap Video challenge. The article includes an embedded video of the winning machine in action.)

ISEA (International Symposium on Electronic Arts) 2020: Why Sentience? still in October 2020 but virtually in Montréal, Québec

I wonder what happens to geography and time when you hold your conference virtually? Part of the excitement of a conference or other meetings is the promise of the destination with new people and new adventures. Whether 2020 is a pause between in-person meetings, a moment when everything changed, or some combination is yet to be determined but perhaps ISEA2020 will be a harbinger.

I received a June 10, 2020 notice (via email) with the latest news about ISEA2020,

Montreal, June 10, 2020    ISEA2020 from October 13 to 18, 2020 goes entirely digital, with an innovative experiential format.

The worldwide COVID-19 outbreak has forced ISEA2020 in Montreal to be postponed to October 13 to 18. The physical distancing measures put in place in many countries and the travel restrictions imposed to prevent the spread of the pandemic mean that we cannot all be physically present in Montreal. Montreal Digital Spring (Printemps numérique) – the organizers of ISEA2020 –  have thus decided to make the symposium a 100% online event. Our team is currently working on the platform that will allow us to come together, connect, and exchange knowledge and practices, despite the physical distance. We worked with our partners and collaborators, experts in art, design, science and technology to (if only begin to) reinvent the format of academic interdisciplinary conferencing! 

Our main strategies for ISEA2020 Online:

Programming: ISEA2020 is a full week of research and creation, 100% online, with more than 300 international speakers and artists from over 40 countries.

Connecting: We are working on the online platform to ensure we meet ISEA’s core values of encouraging and promoting creative exchanges between diverse groups; of creating opportunities for networking and informal meetings, in addition to ensuring the good flow of panel sessions.

Programming for all the time-zones: From October 13 to 16, conference presentations will unfold over 16 consecutive hours each day, in order to include participants in all the time zones, from East Asia to the west Americas.

Reduced registration fee: The registration fee has been reduced. In addition to saving travel costs, ISEA2020 Online is accessible at a significantly reduced fee, hoping it will attract a larger number of participants, including more students and independent artists. 

Live Q&A: All presentation sessions, including keynote sessions, will include live Q&A periods, mediated by invited delegates.

Art Programming:  We are working with artists and partners on strategies to showcase the selected projects and special programming.

While we regret not seeing you in Montreal, the new format will make ISEA2020 accessible to a larger number and will certainly contribute to a broader discussion on how to produce and transfer knowledge and showcase art through connected digital communication platforms. Our team is committed to ensuring the high standard of creative and academic contributions that is paramount to ISEA.

We look forward to seeing you online this fall!


You can now purchase your ISEA2020 Online Pass at the Early Bird rates of CAD $99 (regular) and CAD $69 (students), offer valid until August 13 [2020].


The deadline to register, to upload the camera-ready papers, and to fill in the Zone Festival form is July 27 at 11:59 pm (GMT-5). 


We updated our website. Please refer to the Frequently Asked Questions – FAQ page. If you have a specific question, please contact: for academic presentations / for artworks / for general questions/registration. 


How we got here

The academic chairs have written this statement,

OCTOBER 13-18, 2020

The academic chairs’ statements regarding the ISEA2020 online turn:

Since last August [2019] when we established the ISEA2020 theme of “Why Sentience?”, life on Earth has been dramatically transformed. Our belief in concepts like proximity, justice, equality, indeed, the very concept of the future itself, has been radically uprooted. As cultural organizations worldwide scramble to adapt, the ISEA2020 team has decided to reimagine the event for the anytime/anyplace zone of digital space and to transform it into an online experience. But we have also realized that there is no need to adjust the theme to make it more “responsive” to our current conditions. Despite their almost cataclysmic impact on the political-economic-social-cultural-ecological fabric of the world, the triumvirate forces of the coronavirus pandemic, its disastrous economic consequences, as well as systemic racial injustice have now acutely amplified ISEA2020s question: “Why Sentience?” These conditions sharpen the need to stop, pause and re-examine what it means to be sentient, “the ability to feel or perceive.” They help us reformulate our notions of what the world is with us and beyond us. They give us a front seat perspective on the corporeal and ecological entanglements between power and knowledge, animals and humans, machines and environment, oppression and liberation. They pointedly demonstrate that difference—social-economic-cultural—resonates through the sentient world. The virus—a 120-160 nm in diameter entity that is invisible to our human senses and considered neither living nor dead but ontologically somewhere in between [emphasis mine]—is thus perversely a great teacher and provides us lessons on how the modern splitting up of the sentient and inanimate worlds increasingly makes no sense.

ISEA’s mission aims to foster interdisciplinary academic discourse and exchange among culturally diverse organizations and individuals working with art, science and technology. As we write, ISEA2020 should have already passed into history. The new digital space of ISEA2020 will link the local community in Montreal with the international one beyond so that we can collectively rethink the form of such an event. The new platform will also allow us to examine close up these new and, at the same time, ongoing historical set of conditions; conditions that demand a response if we are to live in the coming (post)-pandemic world. 

Christine Ross – McGill University (Montreal, Canada)

Chris Salter – Concordia University/Hexagram (Montreal, Canada)

2020 Trailers

There is a conference trailer for this new ‘virtual’ version of the 2020 conference,

Montreal Digital Spring (Printemps numérique) produced both the English language version and this one in French***, Note: Video [credit]: Guillaume Guardia,

I’m not sure why the French language version is so much shorter*** (maybe I found an abridged version?), in any case, the content is quite different and you may want to check out both trailers.

***ETA June 22, 2020 at 1550 PDT: The answer to my question as to why one trailer was shorter? Two different (but this year related) events. I failed to note that the second trailer was for “MTL Connect.” Here is Manuelle Freire’s description (academic programme manager of ISEA2020, Printemps numerique) of MTL Connect,

The latter is an annual event organised in Montreal by Printemps numérique, consisting of different thematic pavilion. This year ISEA2020 is the art and creativity pavilion of MTL Connect, so part of a larger endeavour that is affected by this online turn in its entirety.

As for MTL Connect, there’s this from the homepage,



That’s it for the correction. ***

Meeting technology, cyber security, and local involvement

I emailed (Friday, June 19, 2020) a couple of questions to the organizers which they have kindly answered.

  1. Are you going to be using Zoom as the technology for virtual
    attendance? Will there be security measures for attendees?
  2. [A]re there going to be any local (Vancouver, BC) virtual or in-person get-togethers? By October it might be possible to have small groups (with appropriate precautions) meet in person for ISEA2020 discussions/participation in virtual events held elsewhere. (Just a thought)

They responded by Sunday, June 21, 2020). That is quickly. The short answer to both questions is: “We don’t know yet.”

More specifically, Manuelle Freire (Printemps numerique) had this to say,

I will have to forward your first question regarding the technology of the platform, specifically cybersecurity, to the platform development project manager. Cybersecurity is an important matter that we have discussed internally and will be included in the FAQ and the IEA2020, as soon as we have stabilized the different features of the platform and we are ready to release.

As for the second question,

In what comes to small groups meeting in person. It is indeed possible that groups [might] be able to meet in October [2020], but at this stage, with social distancing and travel restrictions in place, we are still facing degrees of uncertainty. While we regret not meeting everyone in Montréal, moving the symposium 100% online seemed the only safe and certain solution. No in-person activities are scheduled for now.

The questions were also sent to Philippe Pasquier, a locally based (Vancouver, BC) member of the ISEA2020 academic committee and he had this to say about the possibility of local, in-person get-togethers,

As for (2), this is a good idea. Let’s wait and see what will be possible and revisit this idea closer to the date. 

The responses have made me happy. Hearing that they take cybersecurity seriously is downright musical and learning that they are open to local, small, in person get-togethers is spirit-lifting.

Final words

In 2009, I attended an ISEA being held in Northern Ireland and Ireland and asked one of the organizers if any of their symposia had been held in Canada. Yes! Montréal, my source raved at length, hosted a great meeting.

The next Canadian ISEA host was Vancouver in 2015 and guess what? Someone in a lineup was raving about the Montréal meeting. It seems that 1995 meeting has taken on a legendary glow.

It was a privilege being able to attend two meetings in person. Legendary, problematic, or good, the meetings bring together exciting talent and disturbing and/or mind-expanding ideas and experiences. Given the circumstances, the organizers find themselves dealing with, I wish them the best of luck although I’m confident that despite all the obstacles, ISEA2020 will be an extraordinary affair.

On a practical note, the $99 (or less) fee for the online pass is a good deal. (I know because I had to pay for mine when they were here in Vancouver in 2015. By the way, I’ve never regretted a penny of it.)

Brain scan variations

The Scientist is a magazine I do not feature here often enough. The latest issue (June 2020) features a May 20, 2020 opinion piece by Ruth Williams on a recent study about interpretating brain scans—70 different teams of neuroimaging experts were involved (Note: Links have been removed),

In a test of scientific reproducibility, multiple teams of neuroimaging experts from across the globe were asked to independently analyze and interpret the same functional magnetic resonance imaging dataset. The results of the test, published in Nature today (May 20), show that each team performed the analysis in a subtly different manner and that their conclusions varied as a result. While highlighting the cause of the irreproducibility—human methodological decisions—the paper also reveals ways to safeguard future studies against it.

Problems with reproducibility plague all areas of science, and have been particularly highlighted in the fields of psychology and cancer through projects run in part by the Center for Open Science. Now, neuroimaging has come under the spotlight thanks to a collaborative project by neuroimaging experts around the world called the Neuroimaging Analysis Replication and Prediction Study (NARPS).

Neuroimaging, specifically functional magnetic resonance imaging (fMRI), which produces pictures of blood flow patterns in the brain that are thought to relate to neuronal activity, has been criticized in the past for problems such as poor study design and statistical methods, and specifying hypotheses after results are known (SHARKing), says neurologist Alain Dagher of McGill University who was not involved in the study. A particularly memorable criticism of the technique was a paper demonstrating that, without needed statistical corrections, it could identify apparent brain activity in a dead fish.

Perhaps because of such criticisms, nowadays fMRI “is a field that is known to have a lot of cautiousness about statistics and . . . about the sample sizes,” says neuroscientist Tom Schonberg of Tel Aviv University, an author of the paper and co-coordinator of NARPS. Also, unlike in many areas of biology, he adds, the image analysis is computational, not manual, so fewer biases might be expected to creep in.

Schonberg was therefore a little surprised to see the NARPS results, admitting, “it wasn’t easy seeing this variability, but it was what it was.”

The study, led by Schonberg together with psychologist Russell Poldrack of Stanford University and neuroimaging statistician Thomas Nichols of the University of Oxford, recruited independent teams of researchers around the globe to analyze and interpret the same raw neuroimaging data—brain scans of 108 healthy adults taken while the subjects were at rest and while they performed a simple decision-making task about whether to gamble a sum of money.

Each of the 70 research teams taking part used one of three different image analysis software packages. But variations in the final results didn’t depend on these software choices, says Nichols. Instead, they came down to numerous steps in the analysis that each require a human’s decision, such as how to correct for motion of the subjects’ heads, how signal-to-noise ratios are enhanced, how much image smoothing to apply—that is, how strictly the anatomical regions of the brain are defined—and which statistical approaches and thresholds to use.

If this topic interests you, I strongly suggest you read Williams’ article in its entirety.

Here are two links to the paper,

Variability in the analysis of a single neuroimaging dataset by many teams. Nature DOI: Published online: 20 May 2020 Check for updates

This first one seems to be a free version of the paper.

Variability in the analysis of a single neuroimaging dataset by many teams by R. Botvinik-Nezer, F. Holzmeister, C. F. Camerer, et al. (at least 70 authors in total) Nature 582, 84–88 (2020). DOI: Published 20 May 2020 Issue Date 04 June 2020

This version is behind a paywall.

China’s neuromorphic chips: Darwin and Tianjic

I believe that China has more than two neuromorphic chips. The two being featured here are the ones for which I was easily able to find information.

The Darwin chip

The first information (that I stumbled across) about China and a neuromorphic chip (Darwin) was in a December 22, 2015 Science China Press news release on EurekAlert,

Artificial Neural Network (ANN) is a type of information processing system based on mimicking the principles of biological brains, and has been broadly applied in application domains such as pattern recognition, automatic control, signal processing, decision support system and artificial intelligence. Spiking Neural Network (SNN) is a type of biologically-inspired ANN that perform information processing based on discrete-time spikes. It is more biologically realistic than classic ANNs, and can potentially achieve much better performance-power ratio. Recently, researchers from Zhejiang University and Hangzhou Dianzi University in Hangzhou, China successfully developed the Darwin Neural Processing Unit (NPU), a neuromorphic hardware co-processor based on Spiking Neural Networks, fabricated by standard CMOS technology.

With the rapid development of the Internet-of-Things and intelligent hardware systems, a variety of intelligent devices are pervasive in today’s society, providing many services and convenience to people’s lives, but they also raise challenges of running complex intelligent algorithms on small devices. Sponsored by the college of Computer science of Zhejiang University, the research group led by Dr. De Ma from Hangzhou Dianzi university and Dr. Xiaolei Zhu from Zhejiang university has developed a co-processor named as Darwin.The Darwin NPU aims to provide hardware acceleration of intelligent algorithms, with target application domain of resource-constrained, low-power small embeddeddevices. It has been fabricated by 180nm standard CMOS process, supporting a maximum of 2048 neurons, more than 4 million synapses and 15 different possible synaptic delays. It is highly configurable, supporting reconfiguration of SNN topology and many parameters of neurons and synapses.Figure 1 shows photos of the die and the prototype development board, which supports input/output in the form of neural spike trains via USB port.

The successful development ofDarwin demonstrates the feasibility of real-time execution of Spiking Neural Networks in resource-constrained embedded systems. It supports flexible configuration of a multitude of parameters of the neural network, hence it can be used to implement different functionalities as configured by the user. Its potential applications include intelligent hardware systems, robotics, brain-computer interfaces, and others.Since it uses spikes for information processing and transmission,similar to biological neural networks, it may be suitable for analysis and processing of biological spiking neural signals, and building brain-computer interface systems by interfacing with animal or human brains. As a prototype application in Brain-Computer Interfaces, Figure 2 [not included here] describes an application example ofrecognizingthe user’s motor imagery intention via real-time decoding of EEG signals, i.e., whether he is thinking of left or right, and using it to control the movement direction of a basketball in the virtual environment. Different from conventional EEG signal analysis algorithms, the input and output to Darwin are both neural spikes: the input is spike trains that encode EEG signals; after processing by the neural network, the output neuron with the highest firing rate is chosen as the classification result.

The most recent development for this chip was announced in a September 2, 2019 Zhejiang University press release (Note: Links have been removed),

The second generation of the Darwin Neural Processing Unit (Darwin NPU 2) as well as its corresponding toolchain and micro-operating system was released in Hangzhou recently. This research was led by Zhejiang University, with Hangzhou Dianzi University and Huawei Central Research Institute participating in the development and algorisms of the chip. The Darwin NPU 2 can be primarily applied to smart Internet of Things (IoT). It can support up to 150,000 neurons and has achieved the largest-scale neurons on a nationwide basis.

The Darwin NPU 2 is fabricated by standard 55nm CMOS technology. Every “neuromorphic” chip is made up of 576 kernels, each of which can support 256 neurons. It contains over 10 million synapses which can construct a powerful brain-inspired computing system.

“A brain-inspired chip can work like the neurons inside a human brain and it is remarkably unique in image recognition, visual and audio comprehension and naturalistic language processing,” said MA De, an associate professor at the College of Computer Science and Technology on the research team.

“In comparison with traditional chips, brain-inspired chips are more adept at processing ambiguous data, say, perception tasks. Another prominent advantage is their low energy consumption. In the process of information transmission, only those neurons that receive and process spikes will be activated while other neurons will stay dormant. In this case, energy consumption can be extremely low,” said Dr. ZHU Xiaolei at the School of Microelectronics.

To cater to the demands for voice business, Huawei Central Research Institute designed an efficient spiking neural network algorithm in accordance with the defining feature of the Darwin NPU 2 architecture, thereby increasing computing speeds and improving recognition accuracy tremendously.

Scientists have developed a host of applications, including gesture recognition, image recognition, voice recognition and decoding of electroencephalogram (EEG) signals, on the Darwin NPU 2 and reduced energy consumption by at least two orders of magnitude.

In comparison with the first generation of the Darwin NPU which was developed in 2015, the Darwin NPU 2 has escalated the number of neurons by two orders of magnitude from 2048 neurons and augmented the flexibility and plasticity of the chip configuration, thus expanding the potential for applications appreciably. The improvement in the brain-inspired chip will bring in its wake the revolution of computer technology and artificial intelligence. At present, the brain-inspired chip adopts a relatively simplified neuron model, but neurons in a real brain are far more sophisticated and many biological mechanisms have yet to be explored by neuroscientists and biologists. It is expected that in the not-too-distant future, a fascinating improvement on the Darwin NPU 2 will come over the horizon.

I haven’t been able to find a recent (i.e., post 2017) research paper featuring Darwin but there is another chip and research on that one was published in July 2019. First, the news.

The Tianjic chip

A July 31, 2019 article in the New York Times by Cade Metz describes the research and offers what seems to be a jaundiced perspective about the field of neuromorphic computing (Note: A link has been removed),

As corporate giants like Ford, G.M. and Waymo struggle to get their self-driving cars on the road, a team of researchers in China is rethinking autonomous transportation using a souped-up bicycle.

This bike can roll over a bump on its own, staying perfectly upright. When the man walking just behind it says “left,” it turns left, angling back in the direction it came.

It also has eyes: It can follow someone jogging several yards ahead, turning each time the person turns. And if it encounters an obstacle, it can swerve to the side, keeping its balance and continuing its pursuit.

… Chinese researchers who built the bike believe it demonstrates the future of computer hardware. It navigates the world with help from what is called a neuromorphic chip, modeled after the human brain.

Here’s a video, released by the researchers, demonstrating the chip’s abilities,

Now back to back to Metz’s July 31, 2019 article (Note: A link has been removed),

The short video did not show the limitations of the bicycle (which presumably tips over occasionally), and even the researchers who built the bike admitted in an email to The Times that the skills on display could be duplicated with existing computer hardware. But in handling all these skills with a neuromorphic processor, the project highlighted the wider effort to achieve new levels of artificial intelligence with novel kinds of chips.

This effort spans myriad start-up companies and academic labs, as well as big-name tech companies like Google, Intel and IBM. And as the Nature paper demonstrates, the movement is gaining significant momentum in China, a country with little experience designing its own computer processors, but which has invested heavily in the idea of an “A.I. chip.”

If you can get past what seems to be a patronizing attitude, there are some good explanations and cogent criticisms in the piece (Metz’s July 31, 2019 article, Note: Links have been removed),

… it faces significant limitations.

A neural network doesn’t really learn on the fly. Engineers train a neural network for a particular task before sending it out into the real world, and it can’t learn without enormous numbers of examples. OpenAI, a San Francisco artificial intelligence lab, recently built a system that could beat the world’s best players at a complex video game called Dota 2. But the system first spent months playing the game against itself, burning through millions of dollars in computing power.

Researchers aim to build systems that can learn skills in a manner similar to the way people do. And that could require new kinds of computer hardware. Dozens of companies and academic labs are now developing chips specifically for training and operating A.I. systems. The most ambitious projects are the neuromorphic processors, including the Tianjic chip under development at Tsinghua University in China.

Such chips are designed to imitate the network of neurons in the brain, not unlike a neural network but with even greater fidelity, at least in theory.

Neuromorphic chips typically include hundreds of thousands of faux neurons, and rather than just processing 1s and 0s, these neurons operate by trading tiny bursts of electrical signals, “firing” or “spiking” only when input signals reach critical thresholds, as biological neurons do.

Tiernan Ray’s August 3, 2019 article about the chip for offers some thoughtful criticism with a side dish of snark (Note: Links have been removed),

Nature magazine’s cover story [July 31, 2019] is about a Chinese chip [Tianjic chip]that can run traditional deep learning code and also perform “neuromorophic” operations in the same circuitry. The work’s value seems obscured by a lot of hype about “artificial general intelligence” that has no real justification.

The term “artificial general intelligence,” or AGI, doesn’t actually refer to anything, at this point, it is merely a placeholder, a kind of Rorschach Test for people to fill the void with whatever notions they have of what it would mean for a machine to “think” like a person.

Despite that fact, or perhaps because of it, AGI is an ideal marketing term to attach to a lot of efforts in machine learning. Case in point, a research paper featured on the cover of this week’s Nature magazine about a new kind of computer chip developed by researchers at China’s Tsinghua University that could “accelerate the development of AGI,” they claim.

The chip is a strange hybrid of approaches, and is intriguing, but the work leaves unanswered many questions about how it’s made, and how it achieves what researchers claim of it. And some longtime chip observers doubt the impact will be as great as suggested.

“This paper is an example of the good work that China is doing in AI,” says Linley Gwennap, longtime chip-industry observer and principal analyst with chip analysis firm The Linley Group. “But this particular idea isn’t going to take over the world.”

The premise of the paper, “Towards artificial general intelligence with hybrid Tianjic chip architecture,” is that to achieve AGI, computer chips need to change. That’s an idea supported by fervent activity these days in the land of computer chips, with lots of new chip designs being proposed specifically for machine learning.

The Tsinghua authors specifically propose that the mainstream machine learning of today needs to be merged in the same chip with what’s called “neuromorphic computing.” Neuromorphic computing, first conceived by Caltech professor Carver Mead in the early ’80s, has been an obsession for firms including IBM for years, with little practical result.

[Missing details about the chip] … For example, the part is said to have “reconfigurable” circuits, but how the circuits are to be reconfigured is never specified. It could be so-called “field programmable gate array,” or FPGA, technology or something else. Code for the project is not provided by the authors as it often is for such research; the authors offer to provide the code “on reasonable request.”

More important is the fact the chip may have a hard time stacking up to a lot of competing chips out there, says analyst Gwennap. …

What the paper calls ANN and SNN are two very different means of solving similar problems, kind of like rotating (helicopter) and fixed wing (airplane) are for aviation,” says Gwennap. “Ultimately, I expect ANN [?] and SNN [spiking neural network] to serve different end applications, but I don’t see a need to combine them in a single chip; you just end up with a chip that is OK for two things but not great for anything.”

But you also end up generating a lot of buzz, and given the tension between the U.S. and China over all things tech, and especially A.I., the notion China is stealing a march on the U.S. in artificial general intelligence — whatever that may be — is a summer sizzler of a headline.

ANN could be either artificial neural network or something mentioned earlier in Ray’s article, a shortened version of CANN [continuous attractor neural network].

Shelly Fan’s August 7, 2019 article for the SingularityHub is almost as enthusiastic about the work as the podcasters for Nature magazine  were (a little more about that later),

The study shows that China is readily nipping at the heels of Google, Facebook, NVIDIA, and other tech behemoths investing in developing new AI chip designs—hell, with billions in government investment it may have already had a head start. A sweeping AI plan from 2017 looks to catch up with the US on AI technology and application by 2020. By 2030, China’s aiming to be the global leader—and a champion for building general AI that matches humans in intellectual competence.

The country’s ambition is reflected in the team’s parting words.

“Our study is expected to stimulate AGI [artificial general intelligence] development by paving the way to more generalized hardware platforms,” said the authors, led by Dr. Luping Shi at Tsinghua University.

Using nanoscale fabrication, the team arranged 156 FCores, containing roughly 40,000 neurons and 10 million synapses, onto a chip less than a fifth of an inch in length and width. Initial tests showcased the chip’s versatility, in that it can run both SNNs and deep learning algorithms such as the popular convolutional neural network (CNNs) often used in machine vision.

Compared to IBM TrueNorth, the density of Tianjic’s cores increased by 20 percent, speeding up performance ten times and increasing bandwidth at least 100-fold, the team said. When pitted against GPUs, the current hardware darling of machine learning, the chip increased processing throughput up to 100 times, while using just a sliver (1/10,000) of energy.

BTW, Fan is a neuroscientist (from her SingularityHub profile page),

Shelly Xuelai Fan is a neuroscientist-turned-science writer. She completed her PhD in neuroscience at the University of British Columbia, where she developed novel treatments for neurodegeneration. While studying biological brains, she became fascinated with AI and all things biotech. Following graduation, she moved to UCSF [University of California at San Francisco] to study blood-based factors that rejuvenate aged brains. She is the co-founder of Vantastic Media, a media venture that explores science stories through text and video, and runs the award-winning blog Her first book, “Will AI Replace Us?” (Thames & Hudson) will be out April 2019.

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

Towards artificial general intelligence with hybrid Tianjic chip architecture by Jing Pei, Lei Deng, Sen Song, Mingguo Zhao, Youhui Zhang, Shuang Wu, Guanrui Wang, Zhe Zou, Zhenzhi Wu, Wei He, Feng Chen, Ning Deng, Si Wu, Yu Wang, Yujie Wu, Zheyu Yang, Cheng Ma, Guoqi Li, Wentao Han, Huanglong Li, Huaqiang Wu, Rong Zhao, Yuan Xie & Luping Shi. Nature volume 572, pages106–111(2019) DOI: https// Published: 31 July 2019 Issue Date: 01 August 2019

This paper is behind a paywall.

The July 31, 2019 Nature podcast, which includes a segment about the Tianjic chip research from China, which is at the 9 mins. 13 secs. mark (AI hardware) or you can scroll down about 55% of the way to the transcript of the interview with Luke Fleet, the Nature editor who dealt with the paper.

Some thoughts

The pundits put me in mind of my own reaction when I heard about phones that could take pictures. I didn’t see the point but, as it turned out, there was a perfectly good reason for combining what had been two separate activities into one device. It was no longer just a telephone and I had completely missed the point.

This too may be the case with the Tianjic chip. I think it’s too early to say whether or not it represents a new type of chip or if it’s a dead end.

A tangle of silver nanowires for brain-like action

I’ve been meaning to get to this news item from late 2019 as it features work from a team that I’ve been following for a number of years now. First mentioned here in an October 17, 2011 posting, James Gimzewski has been working with researchers at the University of California at Los Angeles (UCLA) and researchers at Japan’s National Institute for Materials Science (NIMS) on neuromorphic computing.

This particular research had a protracted rollout with the paper being published in October 2019 and the last news item about it being published in mid-December 2019.

A December 17, 2029 news item on Nanowerk was the first to alert me to this new work (Note: A link has been removed),

UCLA scientists James Gimzewski and Adam Stieg are part of an international research team that has taken a significant stride toward the goal of creating thinking machines.

Led by researchers at Japan’s National Institute for Materials Science, the team created an experimental device that exhibited characteristics analogous to certain behaviors of the brain — learning, memorization, forgetting, wakefulness and sleep. The paper, published in Scientific Reports (“Emergent dynamics of neuromorphic nanowire networks”), describes a network in a state of continuous flux.

A December 16, 2019 UCLA news release, which originated the news item, offers more detail (Note: A link has been removed),

“This is a system between order and chaos, on the edge of chaos,” said Gimzewski, a UCLA distinguished professor of chemistry and biochemistry, a member of the California NanoSystems Institute at UCLA and a co-author of the study. “The way that the device constantly evolves and shifts mimics the human brain. It can come up with different types of behavior patterns that don’t repeat themselves.”

The research is one early step along a path that could eventually lead to computers that physically and functionally resemble the brain — machines that may be capable of solving problems that contemporary computers struggle with, and that may require much less power than today’s computers do.

The device the researchers studied is made of a tangle of silver nanowires — with an average diameter of just 360 nanometers. (A nanometer is one-billionth of a meter.) The nanowires were coated in an insulating polymer about 1 nanometer thick. Overall, the device itself measured about 10 square millimeters — so small that it would take 25 of them to cover a dime.

Allowed to randomly self-assemble on a silicon wafer, the nanowires formed highly interconnected structures that are remarkably similar to those that form the neocortex, the part of the brain involved with higher functions such as language, perception and cognition.

One trait that differentiates the nanowire network from conventional electronic circuits is that electrons flowing through them cause the physical configuration of the network to change. In the study, electrical current caused silver atoms to migrate from within the polymer coating and form connections where two nanowires overlap. The system had about 10 million of these junctions, which are analogous to the synapses where brain cells connect and communicate.

The researchers attached two electrodes to the brain-like mesh to profile how the network performed. They observed “emergent behavior,” meaning that the network displayed characteristics as a whole that could not be attributed to the individual parts that make it up. This is another trait that makes the network resemble the brain and sets it apart from conventional computers.

After current flowed through the network, the connections between nanowires persisted for as much as one minute in some cases, which resembled the process of learning and memorization in the brain. Other times, the connections shut down abruptly after the charge ended, mimicking the brain’s process of forgetting.

In other experiments, the research team found that with less power flowing in, the device exhibited behavior that corresponds to what neuroscientists see when they use functional MRI scanning to take images of the brain of a sleeping person. With more power, the nanowire network’s behavior corresponded to that of the wakeful brain.

The paper is the latest in a series of publications examining nanowire networks as a brain-inspired system, an area of research that Gimzewski helped pioneer along with Stieg, a UCLA research scientist and an associate director of CNSI.

“Our approach may be useful for generating new types of hardware that are both energy-efficient and capable of processing complex datasets that challenge the limits of modern computers,” said Stieg, a co-author of the study.

The borderline-chaotic activity of the nanowire network resembles not only signaling within the brain but also other natural systems such as weather patterns. That could mean that, with further development, future versions of the device could help model such complex systems.

In other experiments, Gimzewski and Stieg already have coaxed a silver nanowire device to successfully predict statistical trends in Los Angeles traffic patterns based on previous years’ traffic data.

Because of their similarities to the inner workings of the brain, future devices based on nanowire technology could also demonstrate energy efficiency like the brain’s own processing. The human brain operates on power roughly equivalent to what’s used by a 20-watt incandescent bulb. By contrast, computer servers where work-intensive tasks take place — from training for machine learning to executing internet searches — can use the equivalent of many households’ worth of energy, with the attendant carbon footprint.

“In our studies, we have a broader mission than just reprogramming existing computers,” Gimzewski said. “Our vision is a system that will eventually be able to handle tasks that are closer to the way the human being operates.”

The study’s first author, Adrian Diaz-Alvarez, is from the International Center for Material Nanoarchitectonics at Japan’s National Institute for Materials Science. Co-authors include Tomonobu Nakayama and Rintaro Higuchi, also of NIMS; and Zdenka Kuncic at the University of Sydney in Australia.

Caption: (a) Micrograph of the neuromorphic network fabricated by this research team. The network contains of numerous junctions between nanowires, which operate as synaptic elements. When voltage is applied to the network (between the green probes), current pathways (orange) are formed in the network. (b) A Human brain and one of its neuronal networks. The brain is known to have a complex network structure and to operate by means of electrical signal propagation across the network. Credit: NIMS

A November 11, 2019 National Institute for Materials Science (Japan) press release (also on EurekAlert but dated December 25, 2019) first announced the news,

An international joint research team led by NIMS succeeded in fabricating a neuromorphic network composed of numerous metallic nanowires. Using this network, the team was able to generate electrical characteristics similar to those associated with higher order brain functions unique to humans, such as memorization, learning, forgetting, becoming alert and returning to calm. The team then clarified the mechanisms that induced these electrical characteristics.

The development of artificial intelligence (AI) techniques has been rapidly advancing in recent years and has begun impacting our lives in various ways. Although AI processes information in a manner similar to the human brain, the mechanisms by which human brains operate are still largely unknown. Fundamental brain components, such as neurons and the junctions between them (synapses), have been studied in detail. However, many questions concerning the brain as a collective whole need to be answered. For example, we still do not fully understand how the brain performs such functions as memorization, learning and forgetting, and how the brain becomes alert and returns to calm. In addition, live brains are difficult to manipulate in experimental research. For these reasons, the brain remains a “mysterious organ.” A different approach to brain research?in which materials and systems capable of performing brain-like functions are created and their mechanisms are investigated?may be effective in identifying new applications of brain-like information processing and advancing brain science.

The joint research team recently built a complex brain-like network by integrating numerous silver (Ag) nanowires coated with a polymer (PVP) insulating layer approximately 1 nanometer in thickness. A junction between two nanowires forms a variable resistive element (i.e., a synaptic element) that behaves like a neuronal synapse. This nanowire network, which contains a large number of intricately interacting synaptic elements, forms a “neuromorphic network”. When a voltage was applied to the neuromorphic network, it appeared to “struggle” to find optimal current pathways (i.e., the most electrically efficient pathways). The research team measured the processes of current pathway formation, retention and deactivation while electric current was flowing through the network and found that these processes always fluctuate as they progress, similar to the human brain’s memorization, learning, and forgetting processes. The observed temporal fluctuations also resemble the processes by which the brain becomes alert or returns to calm. Brain-like functions simulated by the neuromorphic network were found to occur as the huge number of synaptic elements in the network collectively work to optimize current transport, in the other words, as a result of self-organized and emerging dynamic processes..

The research team is currently developing a brain-like memory device using the neuromorphic network material. The team intends to design the memory device to operate using fundamentally different principles than those used in current computers. For example, while computers are currently designed to spend as much time and electricity as necessary in pursuit of absolutely optimum solutions, the new memory device is intended to make a quick decision within particular limits even though the solution generated may not be absolutely optimum. The team also hopes that this research will facilitate understanding of the brain’s information processing mechanisms.

This project was carried out by an international joint research team led by Tomonobu Nakayama (Deputy Director, International Center for Materials Nanoarchitectonics (WPI-MANA), NIMS), Adrian Diaz Alvarez (Postdoctoral Researcher, WPI-MANA, NIMS), Zdenka Kuncic (Professor, School of Physics, University of Sydney, Australia) and James K. Gimzewski (Professor, California NanoSystems Institute, University of California Los Angeles, USA).

Here at last is a link to and a citation for the paper,

Emergent dynamics of neuromorphic nanowire networks by Adrian Diaz-Alvarez, Rintaro Higuchi, Paula Sanz-Leon, Ido Marcus, Yoshitaka Shingaya, Adam Z. Stieg, James K. Gimzewski, Zdenka Kuncic & Tomonobu Nakayama. Scientific Reports volume 9, Article number: 14920 (2019) DOI: Published: 17 October 2019

This paper is open access.