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Brief note about changes

June 19,2019: Hello! I apologize for this site’s unavailability over the last 10 days or so (June 7 – 18, 2019). Moving to a new web hosting service meant that the ‘law of unintended consequences’ came into play. Fingers crossed that all the problems have been resolved.

On another matter, I’ve accumulated quite a backlog of postings, which I will be resizing (publishing) over the next few months. I’ve been trying to bring that backlog down to a reasonable size for quite some time now but I see more drastic, focused action is required. I will continue posting some more recent news items along with my older pieces.

Nanoflowers for better drug delivery; researchers looking for commercial partners

Caption: Schematic representation of the movement of the flower-like particle as it makes its way through a cellular trap to deliver therapeutic genes. Credit: WSU [Washington State University]

It looks more like a swimming pool with pool toys to me but I imagine that nobody wants to say that they’re sending ‘pool toys’ through your bloodstream. Nanoflowers or flower-shaped nanoparticles sounds nicer.

From a January 10, 2019 news item on Nanowerk,

Washington State University [WSU] researchers have developed a novel way to deliver drugs and therapies into cells at the nanoscale without causing toxic effects that have stymied other such efforts.

The work could someday lead to more effective therapies and diagnostics for cancer and other illnesses.

Led by Yuehe Lin, professor in WSU’s School of Mechanical and Materials Engineering, and Chunlong Chen, senior scientist at the Department of Energy’s Pacific Northwest National Laboratory (PNNL), the research team developed biologically inspired materials at the nanoscale that were able to effectively deliver model therapeutic genes into tumor cells. …

A January 10, 2019 WSU news release (also on EurekAlert) by Tina Hilding, which originated the news item, describes the work in greater detail,

Researchers have been working to develop nanomaterials that can effectively carry therapeutic genes directly into the cells for the treatment of diseases such as cancer. The key issues for gene delivery using nanomaterials are their low delivery efficiency of medicine and potential toxicity.

“To develop nanotechnology for medical purposes, the first thing to consider is toxicity — That is the first concern for doctors,” said Lin.

The flower-like particle the WSU and PNNL team developed is about 150 nanometers in size, or about one thousand times smaller than the width of a piece of paper. It is made of sheets of peptoids, which are similar to natural peptides that make up proteins. The peptoids make for a good drug delivery particle because they’re fairly easy to synthesize and, because they’re similar to natural biological materials, work well in biological systems.

The researchers added fluorescent probes in their peptoid nanoflowers, so they could trace them as they made their way through cells, and they added the element fluorine, which helped the nanoflowers more easily escape from tricky cellular traps that often impede drug delivery.

The flower-like particles loaded with therapeutic genes were able to make their way smoothly out of the predicted cellular trap, enter the heart of the cell, and release their drug there.

“The nanoflowers successfully and rapidly escaped (the cell trap) and exhibited minimal cytotoxicity,” said Lin.

After their initial testing with model drug molecules, the researchers hope to conduct further studies using real medicines.

“This paves a new way for us to develop nanocargoes that can efficiently deliver drug molecules into the cell and offers new opportunities for targeted gene therapies,” he said.

The WSU and PNNL team have filed a patent application for the new technology, and they are seeking industrial partners for further development.

Should you and your company be interested in partnering with the researchers, contact:

  • Yuehe Lin, professor, School of Mechanical and Materials Engineering, 509‑335‑8523, yuehe.lin@wsu.edu
  • Tina Hilding, communications director, Voiland College of Engineering and Architecture, 509‑335‑5095, thilding@wsu.edu

For those who’d like more information, here’s a link to and a citation for the paper,

Efficient Cytosolic Delivery Using Crystalline Nanoflowers Assembled from Fluorinated Peptoids by Yang Song, Mingming Wang, Suiqiong Li, Haibao Jin, Xiaoli Cai, Dan Du, He Li, Chun‐Long Chen, Yuehe Lin. Small DOI: https://doi.org/10.1002/smll.201803544 First published: 22 November 2018

This paper is behind a paywall.

Searchable database for hazardous nanomaterials and a Graphene Verification Programme

I have two relatively recent news bits about nanomaterials, the second being entirely focused on graphene.

Searchable database

A July 9, 2019 news item on Nanowerk announces a means of finding out what hazards may be associated with 300 different nanomaterials (Note: A Link has been removed),

A new search tool for nanomaterials has been published on the European Union Observatory for Nanomaterials (EUON) website. It will enable regulators to form a better view of available data and give consumers access to chemicals safety information.

The tool combines data submitted by companies in their REACH registrations [Registration, Evaluation, Authorisation and Restriction of Chemicals (REACH) ], data collected about nanomaterials used as ingredients in cosmetic products under the Cosmetics Regulation and data from the public national nanomaterial inventories of Belgium and France.

A July 3, 2019 EUON press release, which originated the news item, provides a bit more detail,

The EUON’s search brings data from these sources together in one place, allowing users to easily search for nanomaterials that are currently on the EU market. The results are linked to ECHA’s [European Chemicals Agency] database of chemicals registered in the EU and, for the first time, summarised information about the substances, their properties as well as detailed safety and characterisation data can be easily found.

Background

While there are over 300 nanomaterials on the EU market, 37 are currently covered by an existing registration under REACH. The information requirements for REACH were revised last year with explicit obligations for nanomaterials manufactured in or imported to the EU. The new requirements enter into force in January 2020 and will result in more publicly available information.

The EUON aims to increase the transparency of information available to the public on the safety and markets of nanomaterials in the EU. A key aim of the observatory is to create a one-stop shop for information, where EU citizens and stakeholders including NGOs, industry, and regulators can all easily find accessible and relevant safety information on nanomaterials on the EU market.

Here’s the searchable database.

Graphene verification

There was a bit of a scandal about fake graphene in the Fall of 2018 (my May 28, 2019 posting gives details). Dexter Johnson provides additional insight and information about the launch of a new graphene verification programme and news of a slightly older graphene verification programme in his July 9, 2019 article for the Nanoclast blog on the IEEE (Institute of Electrical and Electronics Engineers) website (Note: Links have been removed),

Last year [2018], the graphene community was rocked by a series of critical articles that appeared in some high-profile journals. First there was an Advanced Material’s article with the rather innocuously title: “The Worldwide Graphene Flake Production”. It was perhaps the follow-up article that appeared in the journal Nature that really shook things up with its incendiary title: “The war on fake graphene”.

In these two articles it was revealed that material that had been claimed to be high-quality (and high-priced) graphene was little more than graphite powder. Boosted by their appearance in high-impact journals, these articles threatened the foundations of the graphene marketplace.

But while these articles triggered a lot of hand wringing among the buyers and sellers of graphene, it’s not clear that their impact extended much beyond the supply chain of graphene. Whether or not graphene has aggregated back to being graphite is one question. An even bigger one is whether or not consumers are actually being sold a better product on the basis that it incorporates graphene.

Dexter details some of the issues from the consumer’s perspective (Note: Links have been removed),

Consumer products featuring graphene today include everything from headphones to light bulbs. Consequently, there is already confusion among buyers about the tangible benefits graphene is supposed to provide. And of course the situation becomes even worse if the graphene sold to make products may not even be graphene: how are consumers supposed to determine whether graphene infuses their products with anything other than a buzzword?

Another source of confusion arises because when graphene is incorporated into a product it is effectively a different animal from graphene in isolation. There is ample scientific evidence that graphene when included in a material matrix, like a polymer or even paper, can impart new properties to the materials. “You can transfer some very useful properties of graphene into other materials by adding graphene, but just because the resultant material contains graphene it does not mean it will behave like free-standing graphene, explains Tom Eldridge, of UK-based Fullerex, a consultancy that provides companies with information on how to include graphene in a material matrix

The rest of Dexter’s posting goes on to mention two new graphene verification progammes (producer and product) available through The Graphene Council. As for what the council is, there’s this from council’s About webpage,

The Graphene Council was founded in 2013 with a mission to serve the global community of graphene professionals. Today, The Graphene Council is the largest community in the world for graphene researchers, academics, producers, developers, investors, nanotechnologists, regulatory agencies, research institutes, material science specialists and even the general public. We reach more than 50,000 people with an interest in this amazing material. 

Interestingly the council’s offices are located in the US state of North Carolina. (I would have guessed that its headquarters would be in the UK, given the ‘ownership’ the UK has been attempting to establish over graphene Let me clarify, by ownership I mean the Brits want to be recognized as dominant or preeminent in graphene research and commercialization.)

The council’s first verified graphene producer is a company based in the UK as can be seen in an April 1, 2019 posting by council director Terrance Barkan on the council’s blog,

The Graphene Council is pleased to announce that Versarien plc is the first graphene company in the world to successfully complete the Verified Graphene Producer™ program, an independent, third party verification system that involves a physical inspection of the production facilities, a review of the entire production process, a random sample of product material and rigorous characterization and testing by a first class, international materials laboratory.

The Verified Graphene Producer™ program is an important step to bring transparency and clarity to a rapidly changing and opaque market for graphene materials, providing graphene customers with a level of confidence that has not existed before.

“We are pleased to have worked with the National Physical Laboratory (NPL) in the UK, regarded as one of the absolute top facilities for metrology and graphene characterization in the world.
 
They have provided outstanding analytical expertise for the materials testing portion of the program including Raman Spectroscopy, XPS, AFM and SEM testing services.” stated Terrance Barkan CAE, Executive Director of The Graphene Council.
 
Andrew Pollard, Science Area Leader of the Surface Technology Group, National Physical Laboratory, said: “In order to develop real-world products that can benefit from the ‘wonder material’, graphene, we first need to fully understand its properties, reliably and reproducibly.
 
“Whilst international measurement standards are currently being developed, it is critical that material characterisation is performed to the highest possible level.
 
As the UK’s National Measurement Institute (NMI) with a focus on developing the metrology of graphene and related 2D materials, we aim to be an independent third party in the testing of graphene material for companies and associations around the world, such as The Graphene Council.” 
 
Neill Ricketts, CEO of Versarien said: “We are delighted that Versarien is the first graphene producer in the world to successfully complete the Graphene Council’s Verified Graphene Producer™ programme.”
 
“This is a huge validation of our technology and will enable our partners and potential customers to have confidence that the graphene we produce meets globally accepted standards.”
 
“There are many companies that claim to be graphene producers, but to enjoy the benefits that this material can deliver requires high quality, consistent product to be supplied.  The Verified Producer programme is designed to verify that our production facilities, processes and tested material meet the stringent requirements laid down by The Graphene Council.”

“I am proud that Versarien has been independently acclaimed as a Verified Graphene Producer™ and look forward to making further progress with our collaboration partners and numerous other parties that we are in discussions with.”

James Baker CEng FIET, the CEO of Graphene@Manchester (which includes coordinating the efforts of the National Graphene Institute and the Graphene Engineering and Innovation Centre [GEIC]) stated: “We applaud The Graphene Council for promoting independent third party verification for graphene producers that is supported by world class metrology and characterization services.”

“This is an important contribution to the commercialization of graphene as an industrial material and are proud to have The Graphene Council as an Affiliate Member of the Graphene Engineering and Innovation Centre (GEIC) here in Manchester ”.

Successful commercialization of graphene materials requires not only the ability to produce graphene to a declared specification but to be able to do so at a commercial scale.
It is nearly impossible for a graphene customer to verify the type of material they are receiving without going through an expensive and time consuming process of having sample materials fully characterized by a laboratory that has the equipment and expertise to test graphene.

The Verified Graphene Producer™ program developed by The Graphene Councilprovides a level of independent inspection and verification that is not available anywhere else.

As for the “Verified Graphene Product” programme mentioned in Dexter’s article (it’s not included in the excerpts here), I can’t find any sign of it ion the council’s website.

Controlling neurons with light: no batteries or wires needed

Caption: Wireless and battery-free implant with advanced control over targeted neuron groups. Credit: Philipp Gutruf

This January 2, 2019 news item on ScienceDaily describes the object seen in the above and describes the problem it’s designed to solve,

University of Arizona biomedical engineering professor Philipp Gutruf is first author on the paper Fully implantable, optoelectronic systems for battery-free, multimodal operation in neuroscience research, published in Nature Electronics.

Optogenetics is a biological technique that uses light to turn specific neuron groups in the brain on or off. For example, researchers might use optogenetic stimulation to restore movement in case of paralysis or, in the future, to turn off the areas of the brain or spine that cause pain, eliminating the need for — and the increasing dependence on — opioids and other painkillers.

“We’re making these tools to understand how different parts of the brain work,” Gutruf said. “The advantage with optogenetics is that you have cell specificity: You can target specific groups of neurons and investigate their function and relation in the context of the whole brain.”

In optogenetics, researchers load specific neurons with proteins called opsins, which convert light to electrical potentials that make up the function of a neuron. When a researcher shines light on an area of the brain, it activates only the opsin-loaded neurons.

The first iterations of optogenetics involved sending light to the brain through optical fibers, which meant that test subjects were physically tethered to a control station. Researchers went on to develop a battery-free technique using wireless electronics, which meant subjects could move freely.

But these devices still came with their own limitations — they were bulky and often attached visibly outside the skull, they didn’t allow for precise control of the light’s frequency or intensity, and they could only stimulate one area of the brain at a time.

A Dec. 21, 2018 University of Azrizona news release (published Jan. 2, 2019 on EurekAlert), which originated the news item, discusses the work in more detail,

“With this research, we went two to three steps further,” Gutruf said. “We were able to implement digital control over intensity and frequency of the light being emitted, and the devices are very miniaturized, so they can be implanted under the scalp. We can also independently stimulate multiple places in the brain of the same subject, which also wasn’t possible before.”

The ability to control the light’s intensity is critical because it allows researchers to control exactly how much of the brain the light is affecting — the brighter the light, the farther it will reach. In addition, controlling the light’s intensity means controlling the heat generated by the light sources, and avoiding the accidental activation of neurons that are activated by heat.

The wireless, battery-free implants are powered by external oscillating magnetic fields, and, despite their advanced capabilities, are not significantly larger or heavier than past versions. In addition, a new antenna design has eliminated a problem faced by past versions of optogenetic devices, in which the strength of the signal being transmitted to the device varied depending on the angle of the brain: A subject would turn its head and the signal would weaken.

“This system has two antennas in one enclosure, which we switch the signal back and forth very rapidly so we can power the implant at any orientation,” Gutruf said. “In the future, this technique could provide battery-free implants that provide uninterrupted stimulation without the need to remove or replace the device, resulting in less invasive procedures than current pacemaker or stimulation techniques.”

Devices are implanted with a simple surgical procedure similar to surgeries in which humans are fitted with neurostimulators, or “brain pacemakers.” They cause no adverse effects to subjects, and their functionality doesn’t degrade in the body over time. This could have implications for medical devices like pacemakers, which currently need to be replaced every five to 15 years.

The paper also demonstrated that animals implanted with these devices can be safely imaged with computer tomography, or CT, and magnetic resonance imaging, or MRI, which allow for advanced insights into clinically relevant parameters such as the state of bone and tissue and the placement of the device.

This image of a combined MRI (magnetic resonance image) and CT (computer tomography) scan bookends, more or less, the picture of the device which headed this piece,

Combined image analysis with MRI and CT results superimposed on a 3D rendering of the animal implanted with the programmable bilateral multi µ-ILED device. Courtesy: University of Arizona

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

Fully implantable optoelectronic systems for battery-free, multimodal operation in neuroscience research by Philipp Gutruf, Vaishnavi Krishnamurthi, Abraham Vázquez-Guardado, Zhaoqian Xie, Anthony Banks, Chun-Ju Su, Yeshou Xu, Chad R. Haney, Emily A. Waters, Irawati Kandela, Siddharth R. Krishnan, Tyler Ray, John P. Leshock, Yonggang Huang, Debashis Chanda, & John A. Rogers. Nature Electronics volume 1, pages652–660 (2018) DOI: https://doi.org/10.1038/s41928-018-0175-0 Published 13 December 2018

This paper is behind a paywall.

Tapping into wound healing by harnessing the natural healing process

If you’re imagining an enhanced chakra balancing experience or more efficient digestion of your vitamin supplements, you will be a little disappointed in this latest news from the Imperial College of London (ICL). On the other hand, if you have damaged tissue, this discovery could make your recovery much easier. From a January 7, 2019 news item on phys.org,

Materials are widely used to help heal wounds: Collagen sponges help treat burns and pressure sores, and scaffold-like implants are used to repair bones. However, the process of tissue repair changes over time, so scientists are developing biomaterials that interact with tissues as healing takes place

Now, Dr. Ben Almquist and his team at Imperial College London have created a new molecule that could change the way traditional materials work with the body. Known as traction force-activated payloads (TrAPs), their method lets materials talk to the body’s natural repair systems to drive healing.

The researchers say incorporating TrAPs into existing medical materials could revolutionise the way injuries are treated. Dr. Almquist, from Imperial’s Department of Bioengineering, said: “Our technology could help launch a new generation of materials that actively work with tissues to drive healing.”

A January 7, 2019 ICL press release (also on EurekAlert) by Caroline Brogan, which originated the news item, expands on the theme,

After an injury, cells ‘crawl’ through the collagen ‘scaffolds’ found in wounds, like spiders navigating webs. As they move, they pull on the scaffold, which activates hidden healing proteins that begin to repair injured tissue.

The researchers in the study designed TrAPs as a way to recreate this natural healing method. They folded the DNA segments into three-dimensional shapes known as aptamers that cling tightly to proteins. Then, they attached a customisable ‘handle’ that cells can grab onto on one end, before attaching the opposite end to a scaffold such as collagen.

During laboratory testing of their technique, they found that cells pulled on the TrAPs as they crawled through the collagen scaffolds. The pulling made the TrAPs unravel like shoelaces to reveal and activate the healing proteins. These proteins instruct the healing cells to grow and multiply

The researchers also found that by changing the cellular ‘handle’, they can change which type of cell can grab hold and pull, letting them tailor TrAPs to release specific therapeutic proteins based on which cells are present at a given point in time. In doing so, the TrAPs produce materials that can smartly interact with the correct type of cell at the correct time during wound repair.

This is the first time scientists have activated healing proteins using differing cell types in man-made materials. The technique mimics healing methods found in nature. Dr Almquist said: “Creatures from sea sponges to humans use cell movement to activate healing. Our approach mimics this by using the different cell varieties in wounds to drive healing.””

From lab to humans

This approach is adaptable to different cell types, so could be used in a variety of injuries such as fractured bones, scar tissue after heart attacks, and damaged nerves. New techniques are also desperately needed for patients whose wounds won’t heal despite current interventions, like diabetic foot ulcers, which are the leading cause of non-traumatic lower leg amputations.

TrAPs are relatively straightforward to create and are fully man-made, meaning they are easily recreated in different labs and can be scaled up to industrial quantities. Their adaptability also means they could help scientists create new methods for laboratory studies of diseases, stem cells, and tissue development.

Aptamers are currently used as drugs, meaning they are already proven safe and optimised for clinical use. Because TrAPs take advantage of aptamers that are safe for humans, they may be able to take a shorter path to the clinic than methods that start from ground zero.

Dr Almquist said: “TrAPs provide a flexible method of actively communicating with wounds, as well as key instructions when and where they are needed. This intelligent healing is useful during every phase of the healing process, has the potential to increase the body’s chance to recover, and has far-reaching uses on many different types of wounds. This technology could serve as a conductor of wound repair, orchestrating different cells over time to work together to heal damaged tissues.”

The researchers have made available an image and a video abstract illustrating their work,

TrAPs could harness the body’s natural healing powers to repair bone. Courtesy: Imperial College of London

By the way, the video was produced by www.animateyour.science (based in Adelaide, Australia) and they have a very interesting About page,

Our story

Your research is brilliant and novel. I’m sure of it. You might even be a pioneer in your field. But ask yourself honestly, is it enough? Is it truly enough to make a difference in the world?
 
My name is Tullio Rossi, and I founded Animate Your Science on my quest to make a positive impact on society through science.
 
During my Ph.D., I found that my peer-reviewed paper alone wasn’t cutting it. If I wanted to reach my peers, let alone the general public, I needed to communicate my findings in a fun and imaginative way.
 
This realization changed everything and inspired me to create “Lost at Sea,” an award-winning video that reached the hearts and minds of thousands of people.
 
The success of this first video blew my mind. And I got to thinking, maybe other scientists are lost at sea, so to speak. Maybe others want to reach the masses with their research, but just don’t know where to start.
 
This was the day Animate Your Science was born.

Why we do it

What we really want to do is bring science into society. That’s the true value of this company and the reason we believe in it.

We love science but we believe that, if not communicated properly, science is of limited use to society.​
 
As scientists, it’s our privilege and duty to unearth these revelations and package them in a way that appeals to our peers as well as the general public.

Getting back to TrAPS, here’s a link to and a citation for the paper,

Biologically Inspired, Cell‐Selective Release of Aptamer‐Trapped Growth Factors by Traction Forces by Anna Stejskalová, Nuria Oliva, Frances J. England, Benjamin D. Almquist. Advanced Materials DOI: https://doi.org/10.1002/adma.201806380 First published: 07 January 2019

This paper is open access.

Innerspace of a nanoparticle

A Jan. 3, 2019 news item on ScienceDaily touts a new means of transporting DNA-coated nanoparticles (DNA is deoxyribonucleic acid),

This holiday season, scientists at the Center for Functional Nanomaterials (CFN) — a U.S. Department of Energy Office of Science User Facility at Brookhaven National Laboratory — have wrapped a box of a different kind. Using a one-step chemical synthesis method, they engineered hollow metallic nanosized boxes with cube-shaped pores at the corners and demonstrated how these “nanowrappers” can be used to carry and release DNA-coated nanoparticles in a controlled way. The research is reported in a paper published on Dec. 12 [2018] in ACS Central Science, a journal of the American Chemical Society (ACS).

A January 3, 2018 Brookhaven National Laboratory (BNL) news release (also on EurekAlert), which originated the news item, explains the work in more detail (Note: Links have been removed),

“Imagine you have a box but you can only use the outside and not the inside,” said co-author Oleg Gang, leader of the CFN Soft and Bio Nanomaterials Group. “This is how we’ve been dealing with nanoparticles. Most nanoparticle assembly or synthesis methods produce solid nanostructures. We need methods to engineer the internal space of these structures.

“Compared to their solid counterparts, hollow nanostructures have different optical and chemical properties that we would like to use for biomedical, sensing, and catalytic applications,” added corresponding author Fang Lu, a scientist in Gang’s group. “In addition, we can introduce surface openings in the hollow structures where materials such as drugs, biological molecules, and even nanoparticles can enter and exit, depending on the surrounding environment.”

Synthetic strategies have been developed to produce hollow nanostructures with surface pores, but typically the size, shape, and location of these pores cannot be well-controlled. The pores are randomly distributed across the surface, resulting in a Swiss-cheese-like structure. A high level of control over surface openings is needed in order to use nanostructures in practical applications–for example, to load and release nanocargo

In this study, the scientists demonstrated a new pathway for chemically sculpturing gold-silver alloy nanowrappers with cube-shaped corner holes from solid nanocube particles. They used a chemical reaction known as nanoscale galvanic replacement. During this reaction, the atoms in a silver nanocube get replaced by gold ions in an aqueous solution at room temperature. The scientists added a molecule (surfactant, or surface-capping agent) to the solution to direct the leaching of silver and the deposition of gold on specific crystalline facets.

“The atoms on the faces of the cube are arranged differently from those in the corners, and thus different atomic planes are exposed, so the galvanic reaction may not proceed the same way in both areas,” explained Lu. “The surfactant we chose binds to the silver surface just enough–not too strongly or weakly–so that gold and silver can interact. Additionally, the absorption of surfactant is relatively weak on the silver cube’s corners, so the reaction is most active here. The silver gets “eaten” away from its edges, resulting in the formation of corner holes, while gold gets deposited on the rest of the surface to create a gold and silver shell.”

To capture the structural and chemical composition changes of the overall structure at the nanoscale in 3-D and at the atomic level in 2-D as the reaction proceeded over three hours, the scientists used electron microscopes at the CFN. The 2-D electron microscope images with energy-dispersive X-ray spectroscopy (EDX) elemental mapping confirmed that the cubes are hollow and composed of a gold-silver alloy. The 3-D images they obtained through electron tomography revealed that these hollow cubes feature large cube-shaped holes at the corners

“In electron tomography, 2-D images collected at different angles are combined to reconstruct an image of an object in 3-D,” said Gang. “The technique is similar to a CT [computerized tomography] scan used to image internal body structures, but it is carried out on a much smaller size scale and uses electrons instead of x-rays.”

The scientists also confirmed the transformation of nanocubes to nanowrappers through spectroscopy experiments capturing optical changes. The spectra showed that the optical absorption of the nanowrappers can be tuned depending on the reaction time. At their final state, the nanowrappers absorb infrared light.

“The absorption spectrum showed a peak at 1250 nanometers, one of the longest wavelengths reported for nanoscale gold or silver,” said Gang. “Typically, gold and silver nanostructures absorb visible light. However, for various applications, we would like those particles to absorb infrared light–for example, in biomedical applications such as phototherapy.”

Using the synthesized nanowrappers, the scientists then demonstrated how spherical gold nanoparticles of an appropriate size that are capped with DNA could be loaded into and released from the corner openings by changing the concentration of salt in the solution. DNA is negatively charged (owing to the oxygen atoms in its phosphate backbone) and changes its configuration in response to increasing or decreasing concentrations of a positively charged ion such as salt. In high salt concentrations, DNA chains contract because their repulsion is reduced by the salt ions. In low salt concentrations, DNA chains stretch because their repulsive forces push them apart.

When the DNA strands contract, the nanoparticles become small enough to fit in the openings and enter the hollow cavity. The nanoparticles can then be locked within the nanowrapper by decreasing the salt concentration. At this lower concentration, the DNA strands stretch, thereby making the nanoparticles too large to go through the pores. The nanoparticles can leave the structure through a reverse process of increasing and decreasing the salt concentration.

“Our electron microscopy and optical spectroscopy studies confirmed that the nanowrappers can be used to load and release nanoscale components,” said Lu. “In principle, they could be used to release optically or chemically active nanoparticles in particular environments, potentially by changing other parameters such as pH or temperature.”

Going forward, the scientists are interested in assembling the nanowrappers into larger-scale architectures, extending their method to other bimetallic systems, and comparing the internal and external catalytic activity of the nanowrappers.

“We did not expect to see such regular, well-defined holes,” said Gang. “Usually, this level of control is quite difficult to achieve for nanoscale objects. Thus, our discovery of this new pathway of nanoscale structure formation is very exciting. The ability to engineer nano-objects with a high level of control is important not only to understanding why certain processes are happening but also to constructing targeted nanostructures for various applications, from nanomedicine and optics to smart materials and catalysis. Our new synthesis method opens up unique opportunities in these areas.”

“This work was made possible by the world-class expertise in nanomaterial synthesis and capabilities that exist at the CFN,” said CFN Director Charles Black. “In particular, the CFN has a leading program in the synthesis of new materials by assembly of nanoscale components, and state-of-the-art electron microscopy and optical spectroscopy capabilities for studying the 3-D structure of these materials and their interaction with light. All of these characterization capabilities are available to the nanoscience research community through the CFN user program. We look forward to seeing the advances in nano-assembly that emerge as scientists across academia, industry, and government make use of the capabilities in their research.”

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

Tailoring Surface Opening of Hollow Nanocubes and Their Application as Nanocargo Carriers by Fang Lu, Huolin Xin, Weiwei Xia, Mingzhao Liu, Yugang Zhang, Weiping Cai, and Oleg Gang. ACS Cent. Sci., 2018, 4 (12), pp 1742–1750 DOI: 10.1021/acscentsci.8b00778 Publication Date (Web): December 12, 2018

Copyright © 2018 American Chemical Society

This paper is open access.

2019 Canadian Science Policy Conference (Nov.13 – 16, 2019 in Ottawa, Canada) celebrates its 10th year

Congratulations to the folks at the Canadian Science Policy Centre who’ve worked for 10 years to produce an annual, national Canadian Science Policy Conference! That’s a lot of blood, sweat, tears, and determination.

Here are highlights from the 2019 programme as noted in a July 10, 2019 CSPC announcement (received via email),

Theme: Science and Policy

Bringing the Social Sciences into New Policy Spaces: Solution-oriented case studies and dialogue

Organized by Natural Resources Canada

Evidence in Practice: How do decision-makers obtain and use information?
Organized by Evidence for Democracy

Fishing for Open Science Innovation–Should Canada join cOAlition/Plan S?
Organized by Natural Sciences and Engineering Research Council | Social Sciences and Humanities Research Council | Canadian Institutes of Health Research

How the Sciences of Human Behaviour Can Help us Put Knowledge at the Heart of Policymaking
Organized by European Commission – Joint Research Centre

International Research Collaboration in a Polarized World
Organized by Office of the Vice-President, Research & Innovation, University of Toronto

Mapping Dynamic Research Ecosystems: Tapping into new indicators, big data, and emerging technologies
Organized by Natural Sciences and Engineering Research Council

Municipalities: Terrain for innovation
Organized by Fonds de recherche du Québec

National Inuit Strategy on Research (NISR) in Action: Developing an Inuit Nunangat research policy
Organized by Inuit Tapiriit Kanatami

Not a Palaver! How can interdisciplinary, intersectoral and international collaboration be successful?
Organized by UK Research and Innovation

Policy Lessons in the Age of Technological Disruption
Organized by Spindle Strategy Corp.

Precision Policy- Advances in big data analytics and government policy
Organized by Simon Fraser University

Risk, Uncertainty, Unknowns, and Nonsense – Engagement with the public on radiation, nuclear, and climate [sic]
Organized by Centre for the Study of Science and Innovation Policy (CSIP), University of Saskatchewan

The Influence of Indigenous Knowledge on Policy and Practice
Organized by Federation for the Humanities and Social Sciences and Genome British Columbia

The PROMISE OF SCIENCE and Its Implications for Science Policy: Perspectives of Canada’s STI community
Organized by VISTA Science & Technology Inc.

Towards a National Approach to Responsible AI
Organized by Queen’s University

Understanding and Addressing the Challenges for Collaborative Federal Science
Organized by Public Services and Procurement Canada
 
Theme: Science and Society

Artificial Intelligence – How interdisciplinary AI contributes to resilient and just societies
Organized by Economic and Social Research Council (ESRC)

Convergence Science and Tackling Grand Challenges
Organized by Privy Council Office

Creating SciComm: An interactive session connecting scientists, policy makers and the public
Organized by Pixels and Plans | Art the Science

Eating Right, Living Better: Building healthier food systems worldwide
Organized by International Development Research Centre (IDRC)

Fighting the Opioid Crisis by Reducing Stigma in the Media and Using Media to Reduce Stigma
Organized by Carleton University

Harnessing the Power of the Crowd: Innovative solutions to engaging communities in research
Organized by MEOPAR/Fathom Fund

Making Science Communication Happen – Moving from good intentions to getting the job done
Organized by NIVA

Scientists in the Public Space: When discussion turns into a media storm
Organized by Fonds de recherche du Québec

The Public Record: Enabling scientists to be honest brokers of evidence & information in an age of popular misinformation
Organized by  Alberta Environment and Parks – Office of the Chief Scientist
 
Theme: Science, Innovation, and Economic Development

A Winning Formula for Building Regional Innovation Capacity: Skills, research and collaboration
Organized by Colleges and Institutes Canada / National Alliance of Provincial Health Research Organizations

AI as an Enabler of Innovative Competitiveness
Organized by National Research Council Canada

Examining the Role of Data Trusts in Smart Cities Governance
Organized by Compute Ontario

Ontario-First in the Innovation Economy: Impacts of a $1B public-private-partnership on Canadian healthcare commercialization
Organized by FACIT

Open Science is Transforming the Research Landscape
Organized by The Neuro – Montreal Neurological Institute and Hospital

Supports for Women Entrepreneurs: Discussion on existing knowledge, research and innovative methods to dismantle barriers
Organized by Ryerson University

Toward a Quantum Strategy for Canada
Organized by National Research Council Canada

Whose Facts actually Matter? How to truly embrace inclusiveness in science, innovation and policy
Organized by University of Ottawa, Institute for Science, Society and Policy  
Theme: Science and International Affairs

Artificial Intelligence: Building resilience against cyber threats 
Organized  by Simon Fraser University

Lines in the Sand: The struggle for national security in a world [sic]
Organized by David Johnston Research and Technology Park, University of Waterloo

Personhood Rights for Water Bodies: A fad or a path to sustainable development goals?
Organized by University of Waterloo

Research Without Borders: Funding agency case studies on international collaboration
Organized by UK Research and Innovation

Science Diplomacy in a Changing Arctic
Organized by Embassy of Switzerland
Theme: Science and the Next Generation

Empowering Youth Through Self-led and Experiential Learning

Organized by Ingenium – Canada’s Museums of Science and Innovation

SING’ing Indigenous Technoscience: An encounter with the summer internship for Indigenous peoples in Genomics Canada
Organized by University of Alberta

The Role of the Next Generation in Science Diplomacy 
Organized by Fonds de recherche du Québec

What Future for Young Science Policy Practitioners?
Organized by American Association for the Advancement of Science

What Would an Inclusive Innovation Agenda for a New Generation of Indigenous Children in Canada Look Like?
Organized by Ulnooweg – Digital Mikmaq
 
Short Talks 

Global Governance and Emerging ‘High-Risk’ Technologies

Journal of Science Policy & Governance: Engaging students & early career researchers in S&T policy

Mapping Diversity in Post-Disaster Emergency Assistance

Mobilizing Change from Within: A case study on gender equity and internal research funding

Translating Research to Impact Policy – Our journey in concussion policy in canada [sic]

Why Pro-LGBT Policies Can Turn Out to be Innovation Policies? Evidence-based arguments to support diversity in Canada

Wikipedia Editing & Edit-A-Thons: A form of science advocacy  
View CSPC 2019 Program

Comments

It looks like a good programme. I’m particularly excited about the artificial intelligence (AI) sessions and heartened to see more participation from the indigenous community as it continues to organize. For so long, the thought of indigenous science was rejected so it’s good to see these small steps toward recognition and respect.

Also, there are a couple of countries and regions represented at this conference that suggest Canadian policymakers (or policymakers in training) might be opening the door to welcome more than just our US, UK, and European neighbours into the discussion. There’s someone from Chile and someone from the Caribbean (specifically, Barbados) in addition to the sprinkling of Americans, Brits, and Europeans at this year’s conference.

One thing I wasn’t expecting to see was representation by the RCMP (Royal Canadian Mounted Police). Of course, the member (Susheel Gupta) will be on the panel discussing national security. Hopefully this participation is part of a new direction for the RCMP’s public outreach. They definitely need some positive news given the current state of their reputation in Canada.

What’s missing?

The most puzzling thing about this programme is CRISPR and germline editing. Not a single session touches on the subject. Given that the news about the CRISPR twins broke in November 2018 (see my November 28, 2018 posting) and the international furor that followed, I’d expect we’d be discussing it.

Especially in light of the interest in changing the rules in Canada on germline editing. Currently there’s a ban on it and as I noted in my April 26, 2019 posting, there seems to be a campaign to change to lift or alter that ban..

It seems like a glaring omission but perhaps no one made the suggestion and no one organizing committee was able to assemble a panel.

Plus this year too, there’s no mention of the Phoenix Pay System failure. Sure, there’s talk about big data (a panel on Precision Policy) and the previously noted AI sessions but where’s the talk about the failures, specifically, Phoenix, a digital/technology failure.

The Canadian government’s new pay system was an astonishing debacle from when it was first implemented in early 2016 and the saga continues. In the three years since I don’t recall a single session at a Canadian Science Policy Conference where failure of major digital projects and the implications have been discussed. Meanwhile, the Canadian government continues on its merry drive towards more data collection and implementation of AI and other technologies. Shouldn’t we be considering the social and policy implications of this drive and what happens when there’s a failure? I gather the answer is no.

For anyone unfamiliar with the Phoenix failure, it affected every pay system in the Canadian federal government. In a bid to cut costs by centralizing, updating, and further digitizing the system, Phoenix was implemented despite warnings that it wasn’t ready. As I understand it, government employees (273,571 in 2018), to this day, still don’t know if they will get a pay cheque or if they will get the right amount in their pay cheque in any given month.

Finally

Bravo! There are lots of good things happening with the Canadian Science Policy Conferences.

Register here and take advantage of the early bird discount (until August 31,2019).

Science inspired by superheroes, Ant-Man and the Wasp

It’s interesting to see scientists take science fiction and use it as inspiration; something which I think happens more often than we know. After all, when someone asks where you got an idea, it can be difficult to track down the thought process that started it all.

Scientists at Virginia Tech (Virginia Polytechnic Institute and State University) are looking for a new source of inspiration after offering a close examination of how insect-size superheroes, Ant-Man and the Wasp might breathe. From a December 11, 2018 news item on phys.org (Note: A link has been removed),

Max Mikel-Stites and Anne Staples were searching for a sequel.

This summer, Staples, an associate professor in the Department of Biomedical Engineering and Mechanics in the College of Engineering, and graduate student Mikel-Stites published a paper in the inaugural issue of the Journal of Superhero Science titled, “Ant-Man and the Wasp: Microscale Respiration and Microfluidic Technology.”

Now, they needed a new hero.

The two were working with a team of graduate students, brainstorming who could be the superhero subject for their next scientific inquiry. Superman? Batgirl? Aquaman?

Mikel-Stites lobbied for an investigation of Dazzler’s sonoluminescent powers. Staples was curious how Mera, The Princes sof Atlantis, used her hydrokinetic powers.

It turns out, comic books are a great inspiration for scientific discovery.

This month, Mikel-Stites is presenting the findings of their paper at the American Physical Society’s Division of Fluid Dynamics meeting.

The wonder team’s paper looked at how Ant-Man and the Wasp breathe when they shrink down to insect-size and Staples’ lab studied how fluids flow in nature. Insects naturally move fluids and gases efficiently at tiny scales. If engineers can learn how insects breathe, they can use the knowledge to invent new microfluidic technologies.

A November 2018 Virginia Tech news release (also on EurekAlert but published on December 11, 2018) by Nancy Dudek describes the ‘Ant-Man and Wasp respiratory project’ before revealing the inspiration for the team’s new project,

“Before the 2018 ‘Ant-Man and the Wasp’ movie, my lab was already wondering about insect-scale respiration,” said Staples. “I wanted to get people to appreciate different breathing mechanisms.”

For most of Mikel-Stites’ life, he had been nit-picking at the “science” in science-fiction movies.

“I couldn’t watch ‘Armageddon’ once they got up to space station Mir and there was artificial gravity. Things like that have always bothered me. But for ‘Ant-Man and the Wasp’ it was worse,” he said.

Staples and Mikel-Stites decided to join forces to research Ant-Man’s microscale respiration.

Mikel-Stites was stung by what he dubbed “the altitude problem or death-zone dilemma.” For Ant-Man and the Wasp to shrink down to insect size and still breathe, they would have to overcome an atmospheric density similar to the top of Mt. Everest. Their tiny bodies would also require higher metabolisms. For their survival, the Marvel comic universe had to give Ant-Man and the Wasp superhero technologies.

“I thought it would be fun to find a solution for how this small-scale respiration would work,”said Mikel-Stites.”I started digging through Ant-Man’s history. I looped through scenes in the 2015 movie where we could address the physics. Then I did the same thing with trailers from the 2018 movie. I used that to make a list of problems and a list of solutions.”

Ant-Man and the Wasp solve the altitude problem with their superhero suits. In their publication, Mikel-Stites and Staples write that the masks in Ant-Man and the Wasp’s suits contain “a combination of an air pump, a compressor, and a molecular filter including Pym particle technology,” that allows them to breathe while they are insect-sized.

“This publication showed how different physics phenomena can dominate at different size scales, how well-suited organisms are for their particular size, and what happens when you start altering that,” said Mikel-Stites. “It also shows that Hollywood doesn’t always get it right when it comes to science!”

Their manuscript was accepted by the Journal of Superhero Science before the release of the sequel, “Ant-Man and the Wasp.” Mikel-Stites was concerned the blockbuster might include new technologies or change Ant-Man’s canon. If the Marvel comic universe changed between the 2015 ‘Ant-Man’ movie and the sequel, their hypotheses would be debunked and they would be forced to retract their paper.

“I went to the 2018 movie before the manuscript came out in preprint so that if the movie contradicted us we could catch it. But the 2018 movie actually supported everything we had said, which was really nice,” said Mikel-Stites. Most moviegoers simply watched the special effects and left the theater entertained. But Mikel-Stitesleft the movie with confirmation of the paper’s hypotheses.

The Staples lab members are not the only ones interested in tiny technologies. From lab-on-a-chip microfluidic devices to nanoparticles that deliver drugs directly to cells, consumers will ultimately benefit from this small scientific field that delivers big results.

“In both the movies and science, shrinking is a common theme and has been for the last 50-60 years. This idea is something that we all like to think about. Given enough time, we can reach the point where science can take it from the realms of magic into something that we actually have an explanation for,” Mikel-Stites said.

In fact, the Staples lab group has already done just that.

While Mikel-Stites is presenting his superhero science at the APS meeting, his colleague Krishnashis Chatterjee, who recently completed his Ph.D. in engineering mechanics will be presenting his research on fabricating and testing four different insect-inspired micro-fluidic devices.

From fiction to function, the Staples lab likes to have fun along the way.

“I think that it is really important to connect with people and be engaged in science with topics they already know about. With this superhero science paper I wanted to support this mission,” Staples said.

And who did the lab mates choose for their next superhero science subject? The Princess of Atlantis, Mera. They hope they can publish another superhero science paper that really makes waves.

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

Ant-Man and The Wasp: Microscale Respiration and Microfluidic Technology by Anne Staples and Maxwell Mikel-Stites. Superhero Science and Technology (SST) Vol 1 No 1 (2018): https://doi.org/10.24413/sst.2018.1.2474 July 2018 ISSN 2588-7637

This paper is open access.

And, just because the idea of a superhero science journal tickles my fancy, here’s a little more from the journal’s About webpage,

Serial title
Superhero Science and Technolog

Focus and Scope
Superhero Science and Technology (SST) is multi-disciplinary journal that considers new research in the fields of science, technology, engineering and ethics motivated and presented using the superhero genre.

The superhero genre has become one of the most popular in modern cinema. Since the 2000 film X-Men, numerous superhero-themed films based on characters from Marvel Comics and DC Comics have been released. Films such as The Avengers, Iron Man 3, Avengers: Age of Ultron and Captain America: Civil War have all earned in excess of $1 billion dollars at the box office, thus demonstrating their relevance in modern society and popular culture.

Of particular interest for Superhero Science and Technology are articles that motivate new research by using the platform of superheroes, supervillains, their superpowers, superhero/supervillain exploits in Hollywood blockbuster films or superhero/supervillain adventures from comic books. Articles should be written in a manner so that they are accessible to both the academic community and the interested non-scientist i.e. general public, given the popularity of the superhero genre.

Dissemination of content using this approach provides a potential for the researcher to communicate their work to a larger audience, thus increasing their visibility and outreach within and outside of the academic domain.

The scope of the journal includes but is not limited to:
Genetic editing approaches;
Innovations in the field of robotics;
New and advanced materials;
Additive Manufacturing i.e. 3D printing, for both bio and non-bio applications;
Advancements in bio-chemical processing;
Biomimicry technologies;
Space physics, astrophysical and cosmological research;
Developments in propulsion systems;
Responsible innovation;
Ethical issues pertaining to technologies and their use for human enhancement or augmentation.

Open Access Policy
SST is licensed under a Creative Commons Attribution 4.0 International (CC BY 4.0) licence. You are free to use the work, but you have to attribute (refer to) the work in the manner specified by the author or licensor (but not in any way that suggests that they endorse you or your use of the work). The easiest way to refer to an article is to use the HOWTO CITE tool that you’ll find alongside each article in the right sidebar.

I also looked up the editorial team, from the journal’s Editorial Team webpage,

Editor-in-Chief
Dr. Barry W. Fitzgerald, TU Delft, the Netherlands
Editorial Board
Prof. Wim Briels, University of Twente, the Netherlands
Dr. Ian Clancy, University of Limerick, Ireland
Dr. Neil Clancy, University College London, UK
Dr. Tom Hunt, University of Kent, UK
Ass. Prof. Johan Padding, TU Delft, the Netherlands
Ass. Prof. Aimee van Wynsberghe, TU Delft, the Netherlands
Prof. Ilja Voets, TU Eindhoven, the Netherlands


For anyone unfamiliar with the abbreviation, TU stands for University of Technology or Technische Universiteit in Dutch.

Ouchies no more! Not from bandages, anyway.

An adhesive that US and Chinese scientists have developed shows great promise not just for bandages but wearable robotics too. From a December 14, 2018 news item on Nanowerk,

Researchers from the Harvard John A. Paulson School of Engineering and Applied Sciences (SEAS) and Xi’an Jiaotong University in China have developed a new type of adhesive that can strongly adhere wet materials — such as hydrogel and living tissue — and be easily detached with a specific frequency of light.

The adhesives could be used to attach and painlessly detach wound dressings, transdermal drug delivery devices, and wearable robotics.

A December 18, 2018 SEAS news release by Leah Burrows (also on EurekAlert but published Dec. 14, 2018), which originated the news item, delves further,

“Strong adhesion usually requires covalent bonds, physical interactions, or a combination of both,” said Yang Gao, first author of the paper and researcher at Xi’an Jiaotong University. “Adhesion through covalent bonds is hard to remove and adhesion through physical interactions usually requires solvents, which can be time-consuming and environmentally harmful. Our method of using light to trigger detachment is non-invasive and painless.”

The adhesive uses an aqueous solution of polymer chains spread between two, non-sticky materials — like jam between two slices of bread. On their own, the two materials adhere poorly together but the polymer chains act as a molecular suture, stitching the two materials together by forming a network with the two preexisting polymer networks. This process is known as topological entanglement.

When exposed to ultra-violet light, the network of stitches dissolves, separating the two materials.

The researchers, led by Zhigang Suo, the Allen E. and Marilyn M. Puckett Professor of Mechanics and Materials at SEAS, tested adhesion and detachment on a range of materials, sticking together hydrogels; hydrogels and organic tissue; elastomers; hydrogels and elastomers; and hydrogels and inorganic solids.

“Our strategy works across a range of materials and may enable broad applications,” said Kangling Wu, co-lead author and researcher at Xi’an Jiaotong University in China.
While the researchers focused on using UV light to trigger detachment, their work suggests the possibility that the stitching polymer could detach with near-infrared light, a feature which could be applied to a range of new medical procedures.

“In nature, wet materials don’t like to adhere together,” said Suo. “We have discovered a general approach to overcome this challenge. Our molecular sutures can strongly adhere wet materials together. Furthermore, the strong adhesion can be made permanent, transient, or detachable on demand, in response to a cue. So, as we see it, nature is full of loopholes, waiting to be stitched.”

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

Photodetachable Adhesion by Yang Gao, Kangling Wu, Zhigang Suo. https://doi.org/10.1002/adma.201806948 First published: 14 December 2018

This paper is behind a paywall.

Memristors with better mimicry of synapses

It seems to me it’s been quite a while since I’ve stumbled across a memristor story from the University of Micihigan but it was worth waiting for. (Much of the research around memristors has to do with their potential application in neuromorphic (brainlike) computers.) From a December 17, 2018 news item on ScienceDaily,

A new electronic device developed at the University of Michigan can directly model the behaviors of a synapse, which is a connection between two neurons.

For the first time, the way that neurons share or compete for resources can be explored in hardware without the need for complicated circuits.

“Neuroscientists have argued that competition and cooperation behaviors among synapses are very important. Our new memristive devices allow us to implement a faithful model of these behaviors in a solid-state system,” said Wei Lu, U-M professor of electrical and computer engineering and senior author of the study in Nature Materials.

A December 17, 2018 University of Michigan news release (also on EurekAlert), which originated the news item, provides an explanation of memristors and their ‘similarity’ to synapses while providing more details about this latest research,

Memristors are electrical resistors with memory–advanced electronic devices that regulate current based on the history of the voltages applied to them. They can store and process data simultaneously, which makes them a lot more efficient than traditional systems. They could enable new platforms that process a vast number of signals in parallel and are capable of advanced machine learning.

The memristor is a good model for a synapse. It mimics the way that the connections between neurons strengthen or weaken when signals pass through them. But the changes in conductance typically come from changes in the shape of the channels of conductive material within the memristor. These channels–and the memristor’s ability to conduct electricity–could not be precisely controlled in previous devices.

Now, the U-M team has made a memristor in which they have better command of the conducting pathways.They developed a new material out of the semiconductor molybdenum disulfide–a “two-dimensional” material that can be peeled into layers just a few atoms thick. Lu’s team injected lithium ions into the gaps between molybdenum disulfide layers.
They found that if there are enough lithium ions present, the molybdenum sulfide transforms its lattice structure, enabling electrons to run through the film easily as if it were a metal. But in areas with too few lithium ions, the molybdenum sulfide restores its original lattice structure and becomes a semiconductor, and electrical signals have a hard time getting through.

The lithium ions are easy to rearrange within the layer by sliding them with an electric field. This changes the size of the regions that conduct electricity little by little and thereby controls the device’s conductance.

“Because we change the ‘bulk’ properties of the film, the conductance change is much more gradual and much more controllable,” Lu said.

In addition to making the devices behave better, the layered structure enabled Lu’s team to link multiple memristors together through shared lithium ions–creating a kind of connection that is also found in brains. A single neuron’s dendrite, or its signal-receiving end, may have several synapses connecting it to the signaling arms of other neurons. Lu compares the availability of lithium ions to that of a protein that enables synapses to grow.

If the growth of one synapse releases these proteins, called plasticity-related proteins, other synapses nearby can also grow–this is cooperation. Neuroscientists have argued that cooperation between synapses helps to rapidly form vivid memories that last for decades and create associative memories, like a scent that reminds you of your grandmother’s house, for example. If the protein is scarce, one synapse will grow at the expense of the other–and this competition pares down our brains’ connections and keeps them from exploding with signals.
Lu’s team was able to show these phenomena directly using their memristor devices. In the competition scenario, lithium ions were drained away from one side of the device. The side with the lithium ions increased its conductance, emulating the growth, and the conductance of the device with little lithium was stunted.

In a cooperation scenario, they made a memristor network with four devices that can exchange lithium ions, and then siphoned some lithium ions from one device out to the others. In this case, not only could the lithium donor increase its conductance–the other three devices could too, although their signals weren’t as strong.

Lu’s team is currently building networks of memristors like these to explore their potential for neuromorphic computing, which mimics the circuitry of the brain.

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

Ionic modulation and ionic coupling effects in MoS2 devices for neuromorphic computing by Xiaojian Zhu, Da Li, Xiaogan Liang, & Wei D. Lu. Nature Materials (2018) DOI: https://doi.org/10.1038/s41563-018-0248-5 Published 17 December 2018

This paper is behind a paywall.

The researchers have made images illustrating their work available,

A schematic of the molybdenum disulfide layers with lithium ions between them. On the right, the simplified inset shows how the molybdenum disulfide changes its atom arrangements in the presence and absence of the lithium atoms, between a metal (1T’ phase) and semiconductor (2H phase), respectively. Image credit: Xiaojian Zhu, Nanoelectronics Group, University of Michigan.

A diagram of a synapse receiving a signal from one of the connecting neurons. This signal activates the generation of plasticity-related proteins (PRPs), which help a synapse to grow. They can migrate to other synapses, which enables multiple synapses to grow at once. The new device is the first to mimic this process directly, without the need for software or complicated circuits. Image credit: Xiaojian Zhu, Nanoelectronics Group, University of Michigan.
An electron microscope image showing the rectangular gold (Au) electrodes representing signalling neurons and the rounded electrode representing the receiving neuron. The material of molybdenum disulfide layered with lithium connects the electrodes, enabling the simulation of cooperative growth among synapses. Image credit: Xiaojian Zhu, Nanoelectronics Group, University of Michigan.

That’s all folks.

Fields Centre for Quantitative Analysis and Modelling (CQAM) and ArtSci Salon: call for mathematical artworks

Currently, the deadline is July 26, 2019. For information about the call, there’s a July 6, 2019 ArtSci Salon announcement (received via email) about the call). Note: Both the Art/Sci Salon and CQAM are located in Toronto, Ontario but this is not limited to Canadian artists as far as I can tell,

Please, see this quick call!! this is for existing artworks: do you have
any math-related digital work/photography/drawing/ in high res? please
consider submitting!!!

Call for Artworks
Fields CQAM – ArtSci Salon
deadline: July 26, 2019

The Fields Centre for Quantitative Analysis and Modeling and ArtSci
Salon are looking for Mathematically related, Mathematically inspired,
or Mathematically informed artworks to feature on a limited series of
cards and small prints.

Fields CQAM (CQAM https://www.cqam.ca/ … is a research centre
comprised of 11 labs pairing leading researchers and industry from
across Ontario, simultaneously training a new pool of quantitative
scientists while enabling rapid translation of innovations from idea to
implementation. Mathematical modeling data analytics and visualization,
geometry processing and fabrication, health analytics, and human machine
interaction are only a few of the diverse research fields the centre is
engaged in. Please, check their website …for more information.

The artwork will be printed on cards. A limited number of bigger prints
will be distributed to volunteers who have made an outstanding
contribution to Fields CQAM. The selected artist will receive an
honorarium of $300 – $500 [CAD].

GENERAL REQUIREMENTS

– Artworks can engage with a variety of topics in mathematics. For
instance, they can complement themes explored by CQAM labs.

– Acceptable formats are: Black & White or Color digitally generated
artworks (like visualizations, or digitally produced illustrations);
reproductions of paintings and other canvas-based work; photographic
work; drawings and other illustrations etc. Artworks must be high res
(see below)

– Size can vary (5X7in, 4X6in, 5x5in, 3×3 etc., keep in mind that the
artwork must fit a rectangular or squared-shaped – card).

TECHNICAL INSTRUCTIONS

Please, send the following material tracy.barber@cqam.ca via WeTransfer
(use free version) https://wetransfer.com/

– 1 high res (300dpi) image

– a short bio

– a short description of the artwork

The deadline to propose your artwork is July 26, 2019

For more information please contact Tracy Barber (CQAM)
tracy.barber@cqam.ca

Or Roberta Buiani (ArtSci Salon) rbuiani@gmail.com

I’m guessing this art/sci call for artworks is being handled exclusively by the Art/Sci Salon folks since there doesn’t seem to be any additional information about it on the CQAM website.