Although most of the planet is covered by water, only a fraction of it is clean enough for humans to use. Therefore, it is important to recycle this resource whenever possible. Current purification techniques cannot adequately handle the very hot wastewater generated by some industries.
Some oil recovery methods and other industrial processes result in hot wastewater, which requires energy-intensive cooling before it can be purified through traditional reverse osmosis membranes. After purification, the water then needs to be heated before it can be re-used. At such high temperatures, traditional reverse osmosis membranes filter slowly, allowing more salts, solids and other contaminants to get through. Researchers have embedded extremely tiny nanodiamonds — carbon spheres produced by explosions in small, closed containers without oxygen present — onto these membranes in previous studies. Although the membranes effectively and quickly filtered large volumes of water and can protect against fouling, they were not tested with very hot samples. To optimize the membranes for use with hot wastewater, Khorshidi, Sadrzadeh and colleagues wanted to modify the nanodiamond spheres and embed them in a new way.
The team attached amines to nanodiamonds and bathed them in an ethyl acetate solution to prevent the spheres from clumping. Then, a monomer was added that reacted with the amines to create chemical links to the traditional membrane base. Synergistic effects of the amine links and the ethyl acetate treatment resulted in thicker, more temperature-stable membranes, contributing to improvements in their performance. By increasing the amount of amine-enhanced nanodiamonds in the membrane, the researchers obtained higher filtration rates with a greater proportion of impurities being removed, even after 9 hours at 167 F, when compared to membranes without nanodiamonds. The new method produced membranes that could more effectively treat wastewater at high temperatures, the researchers say.
Dropping a cell phone can sometimes cause superficial cracks to appear. But other times, the device can stop working altogether because fractures develop in the material that stores data. Now, researchers reporting in ACS [American Chemical Society] Applied Polymer Materials have made an environmentally friendly, gelatin-based film that can repair itself multiple times and still maintain the electronic signals needed to access a device’s data. The material could be used someday in smart electronics and health-monitoring devices.
Global consumer demand for hand-held smart devices is rapidly growing, but because of their fragility, the amount of electronic waste is also increasing. Self-repairing films have been developed, but most only work a single time, and some are made with potentially harmful agents that curtail their use in biomedical applications. Researchers have tried incorporating gelatin in electronic devices because it is transparent, readily available and safe. In tests, however, damaged gelatin film was not restored quickly. Yu-Chi Chang and colleagues wanted to see if they could make a repeatedly self-healing gelatin-based film that would mend cracks in minutes and preserve electrical functionality.
The researchers mixed gelatin and glucose to create a flexible film that they sandwiched between conductive material to simulate an electronic device. After bending the simulated electronic device, the team saw breaks in the gelatin-glucose film disappear within 3 hours at room temperature and within 10 minutes when warmed to 140 F. Gelatin without glucose did not self-repair under the same conditions. The glucose-based gelatin also transferred an electrical signal following multiple rounds of damage and repair, with an unexpected improvement to the film’s electrical performance. The experiments show that glucose and gelatin probably form reversible and interlocking imide bonds during the healing process. The new film could help maintain the durability of touchscreen and flexible display devices, advanced robotics and assisted health technologies, the researchers say.
The American Chemical Society (ACS) is a nonprofit organization chartered by the U.S. Congress. ACS’ mission is to advance the broader chemistry enterprise and its practitioners for the benefit of Earth and its people. The Society is a global leader in providing access to chemistry-related information and research through its multiple research solutions, peer-reviewed journals, scientific conferences, eBooks and weekly news periodical Chemical & Engineering News. ACS journals are among the most cited, most trusted and most read within the scientific literature; however, ACS itself does not conduct chemical research. As a specialist in scientific information solutions (including SciFinder® and STN®), its CAS division powers global research, discovery and innovation. ACS’ main offices are in Washington, D.C., and Columbus, Ohio.
One comment: Despite use of the term ‘resistive memory device’ in the title, they are not talking about the memristor (for memory resistor; a circuit element), often featured here in pieces about neuromorphic (brainlike) computing.
There’s nothing especially new in this latest paper on neuromorphic computing and memristors, however it does a very good job of describing how these new computers might work. From a Nov. 30, 2020 news item on phys.org (Note: A link has been removed),
In a paper published in Nano, researchers study the role of memristors in neuromorphic computing. This novel fundamental electronic component supports the cloning of bio-neural systems with low cost and power.
Contemporary computing systems are unable to deal with critical challenges of size reduction and computing speed in the big data era. The Von Neumann bottleneck is referred to as a hindrance in data transfer through the bus connecting processor and memory cell. This gives an opportunity to create alternative architectures based on a biological neuron model. Neuromorphic computing is one of such alternative architectures that mimic neuro-biological brain architectures.
The humanoid neural brain system comprises approximately 100 billion neurons and numerous synapses of connectivity. An efficient circuit device is therefore essential for the construction of a neural network that mimics the human brain. The development of a basic electrical component, the memristor, with several distinctive features such as scalability, in-memory processing and CMOS compatibility, has significantly facilitated the implementation of neural network hardware.
The memristor was introduced as a “memory-like resistor” where the background of the applied inputs would alter the resistance status of the device. It is a capable electronic component that can memorise the current in order to effectively reduce the size of the device and increase processing speed in neural networks. Parallel calculations, as in the human nervous system, are made with the support of memristor devices in a novel computing architecture.
System instability and uncertainty have been described as current problems for most memory-based applications. This is the opposite of the biological process. Despite noise, nonlinearity, variability and volatility, biological systems work well. It is still unclear, however, that the effectiveness of biological systems actually depends on these obstacles. Neural modeling is sometimes avoided because it is not easy to model and study. The possibility of exploiting these properties is therefore, of course, a critical path to success in the achievement of artificial and biological systems.
Here’s a link to and a citation for the paper (Note: I usually include the link as part of the paper’s title but couldn’t do it this time),
Memristors: Understanding, Utilization and Upgradation for Neuromorphic Computing [https://www.worldscientific.com/doi/abs/10.1142/S1793292020300054] by Mohanbabu Bharathi, Zhiwei Wang, Bingrui Guo, Babu Balraj, Qiuhong Li, Jianwei Shuai and Donghui Guo. NanoVol. 15, No. 11, 2030005 (2020) DOI: https://doi.org/10.1142/S1793292020300054 Published: 12 November 2020
An Oct. 29, 2020 news item on ScienceDaily features an explanation of the reasons for investigating brainlike (neuromorphic) computing ,
As progress in traditional computing slows, new forms of computing are coming to the forefront. At Penn State, a team of engineers is attempting to pioneer a type of computing that mimics the efficiency of the brain’s neural networks while exploiting the brain’s analog nature.
Modern computing is digital, made up of two states, on-off or one and zero. An analog computer, like the brain, has many possible states. It is the difference between flipping a light switch on or off and turning a dimmer switch to varying amounts of lighting.
Neuromorphic or brain-inspired computing has been studied for more than 40 years, according to Saptarshi Das, the team leader and Penn State [Pennsylvania State University] assistant professor of engineering science and mechanics. What’s new is that as the limits of digital computing have been reached, the need for high-speed image processing, for instance for self-driving cars, has grown. The rise of big data, which requires types of pattern recognition for which the brain architecture is particularly well suited, is another driver in the pursuit of neuromorphic computing.
“We have powerful computers, no doubt about that, the problem is you have to store the memory in one place and do the computing somewhere else,” Das said.
The shuttling of this data from memory to logic and back again takes a lot of energy and slows the speed of computing. In addition, this computer architecture requires a lot of space. If the computation and memory storage could be located in the same space, this bottleneck could be eliminated.
“We are creating artificial neural networks, which seek to emulate the energy and area efficiencies of the brain,” explained Thomas Shranghamer, a doctoral student in the Das group and first author on a paper recently published in Nature Communications. “The brain is so compact it can fit on top of your shoulders, whereas a modern supercomputer takes up a space the size of two or three tennis courts.”
Like synapses connecting the neurons in the brain that can be reconfigured, the artificial neural networks the team is building can be reconfigured by applying a brief electric field to a sheet of graphene, the one-atomic-thick layer of carbon atoms. In this work they show at least 16 possible memory states, as opposed to the two in most oxide-based memristors, or memory resistors [emphasis mine].
“What we have shown is that we can control a large number of memory states with precision using simple graphene field effect transistors [emphasis mine],” Das said.
The team thinks that ramping up this technology to a commercial scale is feasible. With many of the largest semiconductor companies actively pursuing neuromorphic computing, Das believes they will find this work of interest.
I have a number of items from Simon Fraser University’s (SFU) Metacreation Lab January 2021 newsletter (received via email on Jan. 5, 2020).
29th International Joint Conference on Artificial Intelligence and the 17th Pacific Rim International Conference on Artificial Intelligence! or IJCAI-PRICAI2020 being held on Jan. 7 – 15, 2021
This first excerpt features a conference that’s currently taking place,,
Musical Metacreation Tutorial at IIJCAI – PRICAI 2020 [Yes, the 29th International Joint Conference on Artificial Intelligence and the 17th Pacific Rim International Conference on Artificial Intelligence or IJCAI-PRICAI2020 is being held in 2021!]
The tutorial will be held this Friday, January 8th, from 9 am to 12:20 pm JST ([JST = Japanese Standard Time] 12 am to 3:20 am UTC [or 4 pm – 7:30 pm PST]) and a full description of the syllabus can be found here. For details about registration for the conference and tutorials, click below.
The conference will be held at a virtual venue created by Virtual Chair on the gather.town platform, which offers the spontaneity of mingling with colleagues from all over the world while in the comfort of your home. The platform will allow attendees to customize avatars to fit their mood, enjoy a virtual traditional Japanese village, take part in plenary talks and more.
Two calls for papers
These two excerpts from SFU’s Metacreation Lab January 2021 newsletter feature one upcoming conference and an upcoming workshop, both with calls for papers,
2nd Conference on AI Music Creativity (MuMe + CSMC)
The second Conference on AI Music Creativity brings together two overlapping research forums: The Computer Simulation of Music Creativity Conference (est. 2016) and The International Workshop on Musical Metacreation (est. 2012). The objective of the conference is to bring together scholars and artists interested in the emulation and extension of musical creativity through computational means and to provide them with an interdisciplinary platform in which to present and discuss their work in scientific and artistic contexts.
The 2021 Conference on AI Music Creativity will be hosted by the Institute of Electronic Music and Acoustics (IEM) of the University of Music and Performing Arts of Graz, Austria and held online. The five-day program will feature paper presentations, concerts, panel discussions, workshops, tutorials, sound installations and two keynotes.
The 3rd IEEE Workshop on Artificial Intelligence for Art Creation (AIART) workshop has been announced for 2021. to bring forward cutting-edge technologies and most recent advances in the area of AI art in terms of enabling creation, analysis and understanding technologies. The theme topic of the workshop will be AI creativity, and will be accompanied by a Special Issue of the renowned SCI journal.
AIART is inviting high-quality papers presenting or addressing issues related to AI art, in a wide range of topics. The submission due date is January 31, 2021, and you can learn about the wide range of topics accepted below:
SFU’s Metacreation Lab January 2021 newsletter also features a kind of musical toy,
MMM : Multi-Track Music Machine
One of the latest projects at the Metacreation Lab is MMM: a generative music generation system based on Transformer architecture, capable of generating multi-track music, developed by Jeff Enns and Philippe Pasquier.
Based on an auto-regressive model, the system is capable of generating music from scratch using a wide range of preset instruments. Inputs from one or several tracks can condition the generation of new tracks, resampling MIDI input from the user or adding further layers of music.
To learn more about the system and see it in action, click below and watch the demonstration video, hear some examples, or try the program yourself through Google Colab.
Finally, for anyone who was wondering what happened at the 2020 International Symposium of Electronic Arts (ISEA 2020) held virtually in Montreal in the fall, here’s some news from SFU’s Metacreation Lab January 2021 newsletter,
ISEA2020 Recap // Why Sentience?
As we look back at one of the most unprecedented years, some of the questions explored at ISEA2020 are more salient now than ever. This recap video highlights some of the most memorable moments from last year’s virtual symposium.
The video is a slick, flashy, and fun 15 minutes or so. In addition to the recap for ISEA 2020, there’s a plug for ISEA 2022 in Barcelona, Spain.
The proceedings took my system a while to download (there are approximately 700 pp.). By the way, here’s another link to the proceedings or rather to the archives for the 2020 and previous years’ ISEA proceedings.
“Plus ça change, plus c’est la même chose (the more things change, the more things stay the same), is an old French expression that came to mind when I stumbled across two stories about genetic manipulation of food-producing plants.
The first story involves CRISPR (clustered regularly interspersed short palindromic repeats) gene editing and the second involves more ancient ways to manipulate plant genetics.
Getting ‘CRISPR’d’ plant cells to grow into plants
An October 13, 2020 news item on phys.org announces research about getting better results after a plant’s genome has been altered,
Researchers know how to make precise genetic changes within the genomes of crops, but the transformed cells often refuse to grow into plants. One team has devised a new solution.
Scientists who want to improve crops face a dilemma: it can be difficult to grow plants from cells after you’ve tweaked their genomes.
A new tool helps ease this process by coaxing the transformed cells, including those modified with the gene-editing system CRISPR-Cas9, to regenerate new plants. Howard Hughes Medical Institute Research Specialist Juan M. Debernardi and Investigator Jorge Dubcovsky, together with David Tricoli at the University of California, Davis [UC Davis] Plant Transformation Facility, Javier Palatnik from Argentina, and colleagues at the John Innes Center [UK], collaborated on the work. The team reports the technology, developed in wheat and tested in other crops, October 12, 2020, in the journal Nature Biotechnology.
“The problem is that transforming a plant is still an art [emphasis mine],” Dubcovsky says. The success rate is often low – depending on the crop being modified, 100 attempts may yield only a handful of green shoots that can turn into full-grown plants. The rest fail to produce new plants and die. Now, however, “we have reduced this barrier,” says Dubcovsky, a plant geneticist at UC Davis. Using two genes that already control development in many plants, his team dramatically increased the formation of shoots in modified wheat, rice, citrus, and other crops.
Although UC Davis has a pending patent for commercial applications, Dubcovsky says the technique is available to any researcher who wants to use it for research, at no charge. A number of plant breeding companies have also expressed interested in licensing it. “Now people are trying it in multiple crops,” he says.
Humans have worked to improve plants since the dawn of agriculture, selecting wild grasses to produce cultivated maize and wheat, for example. Nowadays, though, CRISPR has given researchers the ability to make changes to the genome with surgical precision. They have used it to create wheat plants with larger grains, generate resistance to fungal infection, design novel tomato plant architectures, and engineer other traits in new plant varieties.
But the process isn’t easy. Scientists start out with plant cells or pieces of tissue, into which they introduce the CRISPR machinery and a small guide to the specific genes they’d like to edit. They must then entice the modified cells into forming a young plant. Most don’t sprout – a problem scientists are still working to understand.
They have tried to find work-arounds, including boosting the expression of certain genes that control early stages of plant development. While this approach has had some success, it can lead to twisted, stunted, sterile plants if not managed properly.Dubcovsky and his colleagues looked at two other growth-promoting genes, GRF and GIF, that work together in young tissues or organs of plants ranging from moss to fruit trees. The team put these genes side-by-side, like a couple holding hands, before adding them to plant cells. “If you go to a dance, you need to find your partner,” Dubcovsky says. “Here, you are tied with a rope to your partner.”
Dubcovsky’s team found that genetically altered wheat, rice, hybrid orange, and other crops produced many more shoots if those experiments included the linked GRF and GIF genes. In experiments with one variety of wheat, the appearance of shoots increased nearly eight-fold. The number of shoots in rice and the hybrid orange, meanwhile, more than doubled and quadrupled, respectively. What’s more, these shoots grew into healthy plants capable of reproducing on their own, with none of the defects that can result when scientists boost other development-controlling genes. That’s because one of the genes is naturally degraded in adult tissues, Dubcovsky says.
Caroline Roper, a plant pathologist at University of California, Riverside who was not involved in the work, plans to use the new technology to study citrus greening, a bacterial disease that kills trees and renders oranges hard and bitter.
To understand how citrus trees can protect themselves, she needs to see how removing certain genes alters their susceptibility to the bacterium — information that could lead to ways to fight the disease. With conventional techniques, it could take at least two years to generate the gene-edited plants she needs. She hopes Dubcovsky’s tool will shorten that timeline.
“Time is of the essence. The growers, they wanted an answer yesterday, because they’re at the brink of having to abandon cultivating citrus,” she says.
For anyone who noticed the reference to citrus greening in the last paragraphs of this news release, I have more information aboutthe disease and efforts to it in an August 6, 2020 posting.
As for the latest in gene editing and regeneration, here’s a link to and a citation for the paper,
I stumbled on this story by Gabriela Serrato Marks for Massive Science almost three years late (it’s a Dec. 5, 2017 article),
There are more than 50 strains of maize, called landraces, grown in Mexico. A landrace is similar to a dog breed: Corgis and Huskies are both dogs, but they were bred to have different traits. Maize domestication worked the same way.
Some landraces of maize can grow in really dry conditions; others grow best in wetter soils. Early maize farmers selectively bred maize landraces that were well-adapted to the conditions on their land, a practice that still continues today in rural areas of Mexico.
If you think this sounds like an early version of genetic engineering, you’d be correct. But nowadays, modern agriculture is moving away from locally adapted strains and traditional farming techniques and toward active gene manipulation. The goal of both traditional landrace development and modern genetic modification has been to create productive, valuable crops, so these two techniques are not necessarily at odds.
But as more farmers converge on similar strains of (potentially genetically modified) seeds instead of developing locally adapted landraces, there are two potential risks: one is losing the cultural legacy of traditional agricultural techniques that have been passed on in families for centuries or even millennia, and another is decreasing crop resilience even as climate variability is increasing.
Mexico is the main importer of US-grown corn, but that imported corn is primarily used to feed livestock. The corn that people eat or use to make tortillas is grown almost entirely in Mexico, which is where landraces come in.
It is a common practice to grow multiple landraces with different traits as an insurance policy against poor growth conditions. The wide range of landraces contains a huge amount of genetic diversity, making it less likely that one adverse event, such as a drought or pest infestation, will wipe out an entire crop. If farmers only grow one type of corn, the whole crop is vulnerable to the same event.
Landraces are also different from most commercially available hybrid strains of corn because they are open pollinating, which means that farmers can save seeds and replant them the next year, saving money and preserving the strain. If a landrace is not grown anymore, its contribution to maize’s genetic diversity is permanently lost.
This diversity was cultivated over generations from maize’s wild cousin, teosinte, by 60 groups of indigenous people in Mexico. Teosinte looks like a skinny, hairier version of maize. It still grows wild in some parts of Central America, but its close relatives have been found, domesticated, at archaeological sites in the region over 9,000 years old. These early maize cobs could easily fit in the palm of your hand – not big enough to be a staple crop that early farmers could depend upon for sustenance. Genetically, they were more similar to wild teosinte than to modern maize.
 archaeologists also found that the cobs in Honduras, which is outside the natural range of teosinte, were larger than cobs of the same age from the original domestication region in southern Mexico. The scientists think that people in Honduras were able to develop more productive maize landraces because their crops were isolated from wild teosinte.
The size and shape of the ancient cobs from Honduras show that early farmers engineered the maize crop [emphasis mine] to make it more productive. They developed unique landraces that were well adapted to local conditions and successfully cultivated enough maize to support their communities. In many ways, they were early geneticists. [emphasis mine] …
We have a lot to learn from the indigenous farmers who were growing maize 4,000 years ago. Their history provides examples of both environmentally sound genetic modification and effective adaptation to climate variability. [emphases mine] …
There have been only two people who have tested the device from Australia but the research raises hope, from an Oct, 28, 2020 news item on ScienceDaily,
A tiny device the size of a small paperclip has been shown to help patients with upper limb paralysis to text, email and even shop online in the first human trial.
The device, Stentrode™, has been implanted successfully in two patients, who both suffer from severe paralysis due to amyotrophic lateral sclerosis (ALS) — also known as motor neuron disease (MND) — and neither had the ability to move their upper limbs.
Published in the Journal of NeuroInterventional Surgery, the results found the Stentrode™ was able to wirelessly restore the transmission of brain impulses out of the body. This enabled the patients to successfully complete daily tasks such as online banking, shopping and texting, which previously had not been available to them.
The Royal Melbourne Hospital’s Professor Peter Mitchell, Neurointervention Service Director and principal investigator on the trial, said the findings were promising and demonstrate the device can be safely implanted and used within the patients.
“This is the first time an operation of this kind has been done, so we couldn’t guarantee there wouldn’t be problems, but in both cases the surgery has gone better than we had hoped,” Professor Mitchell said.
Professor Mitchell implanted the device on the study participants through their blood vessels, next to the brain’s motor cortex, in a procedure involving a small ‘keyhole’ incision in the neck.
“The procedure isn’t easy, in each surgery there were differences depending on the patient’s anatomy, however in both cases the patients were able to leave the hospital only a few days later, which also demonstrates the quick recovery from the surgery,” Professor Mitchell said.
Neurointerventionalist and CEO of Synchron – the research commercial partner – Associate Professor Thomas Oxley, said this was a breakthrough moment for the field of brain-computer interfaces.
“We are excited to report that we have delivered a fully implantable, take home, wireless technology that does not require open brain surgery, which functions to restore freedoms for people with severe disability,” Associate Professor Oxley, who is also co-head of the Vascular Bionics Laboratory at the University of Melbourne, said.
The two patients used the Stentrode™ to control the computer-based operating system, in combination with an eye-tracker for cursor navigation. This meant they did not need a mouse or keyboard.
They also undertook machine learning-assisted training to control multiple mouse click actions, including zoom and left click. The first two patients achieved an average click accuracy of 92 per cent and 93 per cent, respectively, and typing speeds of 14 and 20 characters per minute with predictive text disabled.
University of Melbourne Associate Professor Nicholas Opie, co-head of the Vascular Bionics Laboratory at the University and founding chief technology officer of Synchron said the developments were exciting and the patients involved had a level of freedom restored in their lives.
“Observing the participants use the system to communicate and control a computer with their minds, independently and at home, is truly amazing,” Associate Professor Opie said.
“We are thankful to work with such fantastic participants, and my colleagues and I are honoured to make a difference in their lives. I hope others are inspired by their success.
“Over the last eight years we have drawn on some of the world’s leading medical and engineering minds to create an implant that enables people with paralysis to control external equipment with the power of thought. We are pleased to report that we have achieved this.”
The researchers caution that while it is some years away before the technology, capable of returning independence to complete everyday tasks is publicly available, the global, multidisciplinary team is working tirelessly to make this a reality.
The trial recently received a $AU1.48 million grant from the Australian commonwealth government to expand the trial to hospitals in New South Wales and Queensland, with hopes to enrol more patients.
Stentrode™ was developed by researchers from the University of Melbourne, the Royal Melbourne Hospital, the Florey Institute of Neuroscience and Mental Health, Monash University and the company Synchron Australia – the corporate vehicle established by Associate Professors Thomas Oxley (CEO) and Nicholas Opie (CTO) that aims to develop and commercialise neural bionics technology and products. It draws on some of the world’s leading medical and engineering minds
Researchers demonstrated the success of a fully implantable wireless medical device, the Stentrode™ brain-computer interface (BCI), designed to allow patients with severe paralysis to resume daily tasks — including texting, emailing, shopping and banking online — without the need for open brain surgery. The first-in-human study was published in the Journal of NeuroInterventional Surgery™, the leading international peer-reviewed journal for the clinical field of neurointerventional surgery.
The patients enrolled in the study utilized the Stentrode neuroprosthesis to control the Microsoft Windows 10 operating system in combination with an eye-tracker for cursor navigation, without a mouse or keyboard. The subjects undertook machine learning-assisted training to control multiple mouse-click actions, including zoom and left click.
“This is a breakthrough moment for the field of brain-computer interfaces. We are excited to report that we have delivered a fully implantable, take home, wireless technology that does not require open brain surgery, which functions to restore freedoms for people with severe disability,” said Thomas Oxley, MD, PhD, and CEO of Synchron, a neurovascular bioelectronics medicine company that conducted the research. “Seeing these first heroic patients resume important daily tasks that had become impossible, such as using personal devices to connect with loved ones, confirms our belief that the Stentrode will one day be able to help millions of people with paralysis.”
Graham Felstead, a 75-year-old man living at home with his wife, has experienced severe paralysis due to amyotrophic lateral sclerosis (ALS). He was the first patient enrolled in the first Stentrode clinical study and the first person to have any BCI implanted via the blood vessels. He received the Stentrode implant in August 2019. With the Stentrode, Felstead was able to remotely contact his spouse, increasing his autonomy and reducing her burden of care. Philip O’Keefe, a 60-year-old man with ALS who works part time, was able to control computer devices to conduct work-related tasks and other independent activities after receiving the Stentrode in April 2020. Functional impairment to his fingers, elbows and shoulders had previously inhibited his ability to engage in these efforts.
The Stentrode device is small and flexible enough to safely pass through curving blood vessels, so the implantation procedure is similar to that of a pacemaker and does not require open brain surgery. Entry through the blood vessels may reduce risk of brain tissue inflammation and rejection of the device, which has been an issue for techniques that require direct brain penetration. Implantation is conducted using well-established neurointerventional techniques that do not require any novel automated robotic assistance.
Here’s a link to and a citation for the paper,
Motor neuroprosthesis implanted with neurointerventional surgery improves capacity for activities of daily living tasks in severe paralysis: first in-human experience by Thomas J Oxley, Peter E Yoo, Gil S Rind, Stephen M Ronayne, C M Sarah Lee, Christin Bird, Victoria Hampshire, Rahul P Sharma, Andrew Morokoff, Daryl L Williams, Christopher MacIsaac, Mark E Howard, Lou Irving, Ivan Vrljic, Cameron Williams, Sam E John, Frank Weissenborn, Madeleine Dazenko, Anna H Balabanski, David Friedenberg, Anthony N Burkitt, Yan T Wong, Katharine J Drummond, Patricia Desmond, Douglas Weber, Timothy Denison, Leigh R Hochberg, Susan Mathers, Terence J O’Brien, Clive N May, J Mocco, David B Grayden, Bruce C V Campbell, Peter Mitchell, Nicholas L Opie. Journal of Neurointerventional Surgery, DOI: http://dx.doi.org/10.1136/neurintsurg-2020-016862 Published Online First: 28 October 2020
A Jan. 4, 2021 news item on Nanowerk describes new insights into nanoscale catalysts derived from work at the US Argonne National Laboratory,
Catalysts are integral to countless aspects of modern society. By speeding up important chemical reactions, catalysts support industrial manufacturing and reduce harmful emissions. They also increase efficiency in chemical processes for applications ranging from batteries and transportation to beer and laundry detergent.
As significant as catalysts are, the way they work is often a mystery to scientists. Understanding catalytic processes can help scientists develop more efficient and cost-effective catalysts. In a recent study, scientists from University of Illinois Chicago (UIC) and the U.S. Department of Energy’s (DOE) Argonne National Laboratory discovered that, during a chemical reaction that often quickly degrades catalytic materials, a certain type of catalyst displays exceptionally high stability and durability.
The catalysts in this study are alloy nanoparticles, or nanosized particles made up of multiple metallic elements, such as cobalt, nickel, copper and platinum. These nanoparticles could have multiple practical applications, including water-splitting to generate hydrogen in fuel cells; reduction of carbon dioxide by capturing and converting it into useful materials like methanol; more efficient reactions in biosensors to detect substances in the body; and solar cells that produce heat, electricity and fuel more effectively.
In this study, the scientists investigated “high-entropy” (highly stable) alloy nanoparticles. The team of researchers, led by Reza Shahbazian-Yassar at UIC, used Argonne’s Center for Nanoscale Materials (CNM), a DOE Office of Science user facility, to characterize the particles’ compositions during oxidation, a process that degrades the material and reduces its usefulness in catalytic reactions.
“Using gas flow transmission electron microscopy (TEM) at CNM, we can capture the whole oxidation process in real time and at very high resolution,” said scientist Bob Song from UIC, a lead scientist on the study. “We found that the high-entropy alloy nanoparticles are able to resist oxidation much better than general metal particles.”
To perform the TEM, the scientists embedded the nanoparticles into a silicon nitride membrane and flowed different types of gas through a channel over the particles. A beam of electrons probed the reactions between the particles and the gas, revealing the low rate of oxidation and the migration of certain metals — iron, cobalt, nickel and copper — to the particles’ surfaces during the process.
“Our objective was to understand how fast high-entropy materials react with oxygen and how the chemistry of nanoparticles evolves during such a reaction,” said Shahbazian-Yassar, UIC professor of mechanical and industrial engineering at the College of Engineering.
According to Shahbazian-Yassar, the discoveries made in this research could benefit many energy storage and conversion technologies, such as fuel cells, lithium-air batteries, supercapacitors and catalyst materials. The nanoparticles could also be used to develop corrosion-resistant and high-temperature materials.
“This was a successful showcase of how CNM’s capabilities and services can meet the needs of our collaborators,” said Argonne’s Yuzi Liu, a scientist at CNM. “We have state-of-the-art facilities, and we want to deliver state-of-the-art science as well.”
Through a collaboration between the Canadian Light Source (CLS) and the Vaccine and Infectious Disease Organization-International Vaccine Centre (VIDO-InterVac)—both national research facilities at the University of Saskatchewan (USask) —scientists hope to understand the structural changes happening inside N95 respirator masks after being sterilized for reuse.
Cutting-edge techniques unique to the CLS enable the team to analyze minute details in the masks that would be impossible to see with other methods. CLS Industrial Scientist Toby Bond is using X-rays produced by the synchrotron to see the tightly woven, microscopic fibres that are crucial to the filtering power of N95 respirators.
N95 respirators get their name from their ability to filter at least 95 per cent of particles circulating in the air. These particular masks are used by frontline health-care workers for protection against COVID-19.
However, N95 masks that were intended for one-time use were in short supply globally during the height of the pandemic this spring, and continue to be chronically unavailable in most parts of the world. As a result, health-care agencies and researchers have been looking for ways to sterilize masks for reuse to help ensure an emergency supply.
While previous research has found that certain methods work better at maintaining the integrity of the masks following decontamination, Bond and colleagues want to understand why this happens and how to extend the lifespan of these critical masks.
“We want to use the unique tools we have at the CLS to look at the fibres that actually do the filtering,” Bond said. “We use a specialized X-ray microscope to take tiny CT scans before and after exposing the N95 masks to different decontamination protocols. Previous research has shown that certain methods work better than others, but we don’t currently know what’s going on inside the mask at a microscopic level.”
Bond is working to determine why the N95 mask fibres degrade. This information would enable manufacturers to design more resilient masks and help the medical industry move towards personal protective equipment that is designed to be reusable.
“One thing that’s unique about a synchrotron CT scan is that we can scan a tiny fraction of the mask at high magnification without having to cut small pieces out of it. This is what allows us to do before-and-after imaging, since we can decontaminate the mask in its real-world environment without altering it,” Bond added.
One method for decontaminating N95 masks, called vaporized hydrogen peroxide (VHP), is used to sterilize rooms and equipment in VIDO-InterVac.
“With the outbreak of the pandemic and the recognized potential worldwide shortage of respirators, we were approached by the Saskatchewan Health Authority (SHA) to investigate the possibility of using VHP decontamination on N95 respirators to mitigate a potential shortage,” said VIDO-InterVac Biosafety Officer Tracey Thue.
To date, VIDO-InterVac has sterilized more than 13,000 masks. Studies have demonstrated that N95 masks can undergo multiple VHP decontamination cycles without affecting mask integrity.
When CLS Laboratory Co-ordinator Burke Barlow suggested that the two groups collaborate, Thue offered to run three styles of N95 respirators through their VHP system for Bond’s research. Bond compared the VHP-treated masks to others that he had treated with Moist Heat Incubation (MHI) and autoclaving.
Autoclaving is a common decontamination method that uses hot pressurized steam to sterilize medical devices, however it is the most damaging method and certain masks do not survive even one autoclave sterilization cycle. MHI is gentler than the autoclave, but the masks still become less effective after repeated cycles. VHP is considered to be the best method for decontamination of N95s, but it requires specialized equipment that is not widely available in hospitals.
Bond and his colleagues are using the BMIT beamline at the CLS, a one-of-a-kind tool in North America, to image the inside of the masks in three dimensions without damaging them. The researchers can then look at the structure of individual fibres in the masks to see how they change during decontamination. They can identify shifts in mask fibres as small as a few microns, which is a measurement much smaller than the width of a human hair.
Analyses over the next few weeks will help clarify what effect these shifts have on the performance of the mask. Aerodynamic and fluid simulations conducted at the CLS will help show how the changes in mask fibre structure affect air flow.
“Preliminary results show there is a gradual unravelling of the fibres during repeated exposure to MHI in some masks,” said Bond. “This is in contrast to autoclaving the masks, which immediately causes a very significant unravelling after a single decontamination.”
“In some cases, this unravelling doesn’t affect the filtration, but it does affect the overall structure of the mask, causing it to fit poorly and no longer seal properly to the user’s face,” he added. “This indicates that manufacturers could potentially make an autoclavable mask by changing the structural parts of the mask and leaving the filtration layer as it is.”
“In terms of Toby’s research at the CLS, being able to go down to the microscopic level and visualize changes in the material or lack there-of is another valuable piece of information,” Thue said.
Bond emphasized that it’s not just tools and equipment that makes this kind of research possible at the CLS, but also the access to the vast research network at USask.
“The CLS is a fantastic place to do research like this, since we’re a national facility with a broad network of researchers,” said Bond. “We’ve been able to work with our colleagues at VIDO-InterVac (which is just down the road on the USask campus), and we also have contacts in industry and academia who work in this sector that have helped us with the experiments.”
Oddly, there is no reference to a published paper for this work or mention of future research into how manufacturers might make use of this information.
The cloth masks many are sporting these days offer some protection against COVID-19. However, they typically provide much less than the professional N95 masks used by healthcare workers.
That may soon change. Recently, students from BYU’s [Brigham Young University; Utah, US] College of Engineering teamed up with Nanos Foundation [emphasis mine] to develop a nanofiber membrane that can be sandwiched between the cloth pieces in a homemade mask.
A few questions and a video
There is a video but you might find it helpful to know that when one of the students refers to OSHA she means the US Occupational Safety and Health Agency (OSHA). As for the ‘electrospinning’ I’m not sure how accessible that kind of equipment is, which calls into question how inexpensive and easy it would be to adopt this new mask insert. Fingers crossed that this will be as easy and effective as they seem to be suggesting,
While today’s typical cloth mask might block fewer than 50% of virus particles, the membrane — which can be made using simple, inexpensive materials — will be able to block 90 to 99% of particles, increasing effectiveness [emphasis mine] while preserving breathability.
The membranes are made through a process called “electrospinning,” which involves dissolving a polymer plastic in a solution and then using an electrical current to move a droplet of the polymer downward through a needle. As the droplet accelerates, it stretches into a very small fiber that retains a static charge.
“Those nanofibers randomly land on a collector to create a sort of non-woven mesh,” said Katie Varela, a BYU mechanical engineering senior on the project team.
The remaining charge in the fibers is beneficial, she explained, because virus particles also have a static charge. “When they come close to your mask, they will be statically attracted to the mask and will not be able to go through it, and so it prevents you from inhaling viruses.”
In addition to the dramatic improvement in efficacy [emphasis mine], another key benefit of the nanofiber masks is that unlike traditional N95 masks, which have a reputation for being hot and stuffy, they allow for the circulation of (filtered) air, water and heat.
“Not only is it hard to find an N95 mask these days, but the best mask is useless if you won’t wear it,” said Will Vahle, director at Nanos Foundation. “Our nanofiber membranes are six times easier to breathe through than existing N95 masks, making them cooler, drier, and more comfortable.”
The group plans to make the instructions for creating the membranes open source. They hope that non-profit organizations will use the instructions to set up local sites where people can bring in their masks to be fitted with a membrane. They also hope other engineers will use their work as a springboard to produce more effective filters.
“We had our own proprietary nanofiber production process,” said Vahle of the project’s origins, “but we realized, hey, we have some expertise in this — why don’t we get this together and release a version that anybody can do?”
When Vahle and his colleagues approached BYU to collaborate on the project, BYU “jumped at the opportunity,” Vahle said. In addition to providing funding and facilities, the university connected the company with “fantastic students, who’ve really demonstrated an incredible work ethic and a drive to help people in need.”
Using cutting-edge science to make an immediate positive impact has also been highly valuable for the BYU students on the project.
“This experience makes things very real,” said Varela. “I’m really glad that I’m able to help with this fight against COVID-19 to help people all around the world and in my community.”
I’ve highlighted ‘effectiveness’ and ‘efficacy’, which are not synonyms although they’re often used that way. I can recall being quite surprised on discovering they were not, since I had, up to that point, confused them for many, many years. There’s a good description of the differences in a November 17, 2018 posting on the Public Health Notes website,
So, the difference is between controlled environments for efficacy and real life for effectiveness, in this case, a mask.
Current technology has not been updated since the 1970s. The Nanos technology is inexpensive, portable and accessible.
Our Open-Source process turns common plastics into highly effective respiratory PPE [personal protective equipment].
‘Electrospinning’ nanofibers onto common cloth turns the cloth into a filter → sew the cloth into a mask to produce an effective top notch respirator.
You can use our designs, or bring your own design – 95+ is about the nanofiber membrane that turns the ‘cloth face covering’ into a respirator. Just make sure to use a design that creates a good seal or fit against the face.
The 95+ Process Requires Only A Few Simple Things
The kinds of things that can be easily found, like an old television, paint thinner & recycled plastics
I didn’t find any instructions for how to ‘electrospin’ with an old television, paint thinner, and plastics to make the nanofiber membrane. Perhaps one is required to donate before receiving instructions.
Interestingly, Nanos Foundation has three locations:
Greenville, AL, USA
Providence, RI, USA
I was not expecting a Canadian connection.
While this ‘easy to produce’ plastic insert seems very useful, it’s not clear to me what happens when the mask has to be washed or cleaned in some fashion. How long these nanofiber membranes active? Do we have to keep replacing the nanofiber membranes thereby adding more plastic to the environment?