Tag Archives: Russia

FrogHeart’s 2022 comes to an end as 2023 comes into view

Leave a reply

I look forward to 2023 and hope it will be as stimulating as 2022 proved to be. Here’s an overview of the year that was on this blog:

Sounds of science

It seems 2022 was the year that science discovered the importance of sound and the possibilities of data sonification. Neither is new but this year seemed to signal a surge of interest or maybe I just happened to stumble onto more of the stories than usual.

This is not an exhaustive list, you can check out my ‘Music’ category for more here. I have tried to include audio files with the postings but it all depends on how accessible the researchers have made them.

Aliens on earth: machinic biology and/or biological machinery?

When I first started following stories in 2008 (?) about technology or machinery being integrated with the human body, it was mostly about assistive technologies such as neuroprosthetics. You’ll find most of this year’s material in the ‘Human Enhancement’ category or you can search the tag ‘machine/flesh’.

However, the line between biology and machine became a bit more blurry for me this year. You can see what’s happening in the titles listed below (you may recognize the zenobot story; there was an earlier version of xenobots featured here in 2021):

This was the story that shook me,

Are the aliens going to come from outer space or are we becoming the aliens?

Brains (biological and otherwise), AI, & our latest age of anxiety

As we integrate machines into our bodies, including our brains, there are new issues to consider:

  • Going blind when your neural implant company flirts with bankruptcy (long read) April 5, 2022 posting
  • US National Academies Sept. 22-23, 2022 workshop on techno, legal & ethical issues of brain-machine interfaces (BMIs) September 21, 2022 posting

I hope the US National Academies issues a report on their “Brain-Machine and Related Neural Interface Technologies: Scientific, Technical, Ethical, and Regulatory Issues – A Workshop” for 2023.

Meanwhile the race to create brainlike computers continues and I have a number of posts which can be found under the category of ‘neuromorphic engineering’ or you can use these search terms ‘brainlike computing’ and ‘memristors’.

On the artificial intelligence (AI) side of things, I finally broke down and added an ‘artificial intelligence (AI) category to this blog sometime between May and August 2021. Previously, I had used the ‘robots’ category as a catchall. There are other stories but these ones feature public engagement and policy (btw, it’s a Canadian Science Policy Centre event), respectively,

  • “The “We are AI” series gives citizens a primer on AI” March 23, 2022 posting
  • “Age of AI and Big Data – Impact on Justice, Human Rights and Privacy Zoom event on September 28, 2022 at 12 – 1:30 pm EDT” September 16, 2022 posting

These stories feature problems, which aren’t new but seem to be getting more attention,

While there have been issues over AI, the arts, and creativity previously, this year they sprang into high relief. The list starts with my two-part review of the Vancouver Art Gallery’s AI show; I share most of my concerns in part two. The third post covers intellectual property issues (mostly visual arts but literary arts get a nod too). The fourth post upends the discussion,

  • “Mad, bad, and dangerous to know? Artificial Intelligence at the Vancouver (Canada) Art Gallery (1 of 2): The Objects” July 28, 2022 posting
  • “Mad, bad, and dangerous to know? Artificial Intelligence at the Vancouver (Canada) Art Gallery (2 of 2): Meditations” July 28, 2022 posting
  • “AI (artificial intelligence) and art ethics: a debate + a Botto (AI artist) October 2022 exhibition in the Uk” October 24, 2022 posting
  • Should AI algorithms get patents for their inventions and is anyone talking about copyright for texts written by AI algorithms? August 30, 2022 posting

Interestingly, most of the concerns seem to be coming from the visual and literary arts communities; I haven’t come across major concerns from the music community. (The curious can check out Vancouver’s Metacreation Lab for Artificial Intelligence [located on a Simon Fraser University campus]. I haven’t seen any cautionary or warning essays there; it’s run by an AI and creativity enthusiast [professor Philippe Pasquier]. The dominant but not sole focus is art, i.e., music and AI.)

There is a ‘new kid on the block’ which has been attracting a lot of attention this month. If you’re curious about the latest and greatest AI anxiety,

  • Peter Csathy’s December 21, 2022 Yahoo News article (originally published in The WRAP) makes this proclamation in the headline “Chat GPT Proves That AI Could Be a Major Threat to Hollywood Creatives – and Not Just Below the Line | PRO Insight”
  • Mouhamad Rachini’s December 15, 2022 article for the Canadian Broadcasting Corporation’s (CBC) online news overs a more generalized overview of the ‘new kid’ along with an embedded CBC Radio file which runs approximately 19 mins. 30 secs. It’s titled “ChatGPT a ‘landmark event’ for AI, but what does it mean for the future of human labour and disinformation?” The chat bot’s developer, OpenAI, has been mentioned here many times including the previously listed July 28, 2022 posting (part two of the VAG review) and the October 24, 2022 posting.

Opposite world (quantum physics in Canada)

Quantum computing made more of an impact here (my blog) than usual. it started in 2021 with the announcement of a National Quantum Strategy in the Canadian federal government budget for that year and gained some momentum in 2022:

  • “Quantum Mechanics & Gravity conference (August 15 – 19, 2022) launches Vancouver (Canada)-based Quantum Gravity Institute and more” July 26, 2022 posting Note: This turned into one of my ‘in depth’ pieces where I comment on the ‘Canadian quantum scene’ and highlight the appointment of an expert panel for the Council of Canada Academies’ report on Quantum Technologies.
  • “Bank of Canada and Multiverse Computing model complex networks & cryptocurrencies with quantum computing” July 25, 2022 posting
  • “Canada, quantum technology, and a public relations campaign?” December 29, 2022 posting

This one was a bit of a puzzle with regard to placement in this end-of-year review, it’s quantum but it’s also about brainlike computing

It’s getting hot in here

Fusion energy made some news this year.

There’s a Vancouver area company, General Fusion, highlighted in both postings and the October posting includes an embedded video of Canadian-born rapper Baba Brinkman’s “You Must LENR” [L ow E nergy N uclear R eactions or sometimes L attice E nabled N anoscale R eactions or Cold Fusion or CANR (C hemically A ssisted N uclear R eactions)].

BTW, fusion energy can generate temperatures up to 150 million degrees Celsius.

Ukraine, science, war, and unintended consequences

Here’s what you might expect,

These are the unintended consequences (from Rachel Kyte’s, Dean of the Fletcher School, Tufts University, December 26, 2022 essay on The Conversation [h/t December 27, 2022 news item on phys.org]), Note: Links have been removed,

…

Russian President Vladimir Putin’s war on Ukraine has reverberated through Europe and spread to other countries that have long been dependent on the region for natural gas. But while oil-producing countries and gas lobbyists are arguing for more drilling, global energy investments reflect a quickening transition to cleaner energy. [emphasis mine]

Call it the Putin effect – Russia’s war is speeding up the global shift away from fossil fuels.

In December [2022?], the International Energy Agency [IEA] published two important reports that point to the future of renewable energy.

First, the IEA revised its projection of renewable energy growth upward by 30%. It now expects the world to install as much solar and wind power in the next five years as it installed in the past 50 years.

The second report showed that energy use is becoming more efficient globally, with efficiency increasing by about 2% per year. As energy analyst Kingsmill Bond at the energy research group RMI noted, the two reports together suggest that fossil fuel demand may have peaked. While some low-income countries have been eager for deals to tap their fossil fuel resources, the IEA warns that new fossil fuel production risks becoming stranded, or uneconomic, in the next 20 years.

…

Kyte’s essay is not all ‘sweetness and light’ but it does provide a little optimism.

Kudos, nanotechnology, culture (pop & otherwise), fun, and a farewell in 2022

This one was a surprise for me,

Sometimes I like to know where the money comes from and I was delighted to learn of the Ărramăt Project funded through the federal government’s New Frontiers in Research Fund (NFRF). Here’s more about the Ărramăt Project from the February 14, 2022 posting,

…

“The Ărramăt Project is about respecting the inherent dignity and interconnectedness of peoples and Mother Earth, life and livelihood, identity and expression, biodiversity and sustainability, and stewardship and well-being. Arramăt is a word from the Tamasheq language spoken by the Tuareg people of the Sahel and Sahara regions which reflects this holistic worldview.” (Mariam Wallet Aboubakrine)

Over 150 Indigenous organizations, universities, and other partners will work together to highlight the complex problems of biodiversity loss and its implications for health and well-being. The project Team will take a broad approach and be inclusive of many different worldviews and methods for research (i.e., intersectionality, interdisciplinary, transdisciplinary). Activities will occur in 70 different kinds of ecosystems that are also spiritually, culturally, and economically important to Indigenous Peoples.

The project is led by Indigenous scholars and activists …

Kudos to the federal government and all those involved in the Salmon science camps, the Ărramăt Project, and other NFRF projects.

There are many other nanotechnology posts here but this appeals to my need for something lighter at this point,

  • “Say goodbye to crunchy (ice crystal-laden) in ice cream thanks to cellulose nanocrystals (CNC)” August 22, 2022 posting

The following posts tend to be culture-related, high and/or low but always with a science/nanotechnology edge,

Sadly, it looks like 2022 is the last year that Ada Lovelace Day is to be celebrated.

… this year’s Ada Lovelace Day is the final such event due to lack of financial backing. Suw Charman-Anderson told the BBC [British Broadcasting Corporation] the reason it was now coming to an end was:

You can read more about it here:

In the rearview mirror

A few things that didn’t fit under the previous heads but stood out for me this year. Science podcasts, which were a big feature in 2021, also proliferated in 2022. I think they might have peaked and now (in 2023) we’ll see what survives.

Nanotechnology, the main subject on this blog, continues to be investigated and increasingly integrated into products. You can search the ‘nanotechnology’ category here for posts of interest something I just tried. It surprises even me (I should know better) how broadly nanotechnology is researched and applied.

If you want a nice tidy list, Hamish Johnston in a December 29, 2022 posting on the Physics World Materials blog has this “Materials and nanotechnology: our favourite research in 2022,” Note: Links have been removed,

“Inherited nanobionics” makes its debut

The integration of nanomaterials with living organisms is a hot topic, which is why this research on “inherited nanobionics” is on our list. Ardemis Boghossian at EPFL [École polytechnique fédérale de Lausanne] in Switzerland and colleagues have shown that certain bacteria will take up single-walled carbon nanotubes (SWCNTs). What is more, when the bacteria cells split, the SWCNTs are distributed amongst the daughter cells. The team also found that bacteria containing SWCNTs produce a significantly more electricity when illuminated with light than do bacteria without nanotubes. As a result, the technique could be used to grow living solar cells, which as well as generating clean energy, also have a negative carbon footprint when it comes to manufacturing.

…

Getting to back to Canada, I’m finding Saskatchewan featured more prominently here. They do a good job of promoting their science, especially the folks at the Canadian Light Source (CLS), Canada’s synchrotron, in Saskatoon. Canadian live science outreach events seeming to be coming back (slowly). Cautious organizers (who have a few dollars to spare) are also enthusiastic about hybrid events which combine online and live outreach.

After what seems like a long pause, I’m stumbling across more international news, e.g. “Nigeria and its nanotechnology research” published December 19, 2022 and “China and nanotechnology” published September 6, 2022. I think there’s also an Iran piece here somewhere.

With that …

Making resolutions in the dark

Hopefully this year I will catch up with the Council of Canadian Academies (CCA) output and finally review a few of their 2021 reports such as Leaps and Boundaries; a report on artificial intelligence applied to science inquiry and, perhaps, Powering Discovery; a report on research funding and Natural Sciences and Engineering Research Council of Canada.

Given what appears to a renewed campaign to have germline editing (gene editing which affects all of your descendants) approved in Canada, I might even reach back to a late 2020 CCA report, Research to Reality; somatic gene and engineered cell therapies. it’s not the same as germline editing but gene editing exists on a continuum.

For anyone who wants to see the CCA reports for themselves they can be found here (both in progress and completed).

I’m also going to be paying more attention to how public relations and special interests influence what science is covered and how it’s covered. In doing this 2022 roundup, I noticed that I featured an overview of fusion energy not long before the breakthrough. Indirect influence on this blog?

My post was precipitated by an article by Alex Pasternak in Fast Company. I’m wondering what precipitated Alex Pasternack’s interest in fusion energy since his self-description on the Huffington Post website states this “… focus on the intersections of science, technology, media, politics, and culture. My writing about those and other topics—transportation, design, media, architecture, environment, psychology, art, music … .”

He might simply have received a press release that stimulated his imagination and/or been approached by a communications specialist or publicists with an idea. There’s a reason for why there are so many public relations/media relations jobs and agencies.

Que sera, sera (Whatever will be, will be)

I can confidently predict that 2023 has some surprises in store. I can also confidently predict that the European Union’s big research projects (1B Euros each in funding for the Graphene Flagship and Human Brain Project over a ten year period) will sunset in 2023, ten years after they were first announced in 2013. Unless, the powers that be extend the funding past 2023.

I expect the Canadian quantum community to provide more fodder for me in the form of a 2023 report on Quantum Technologies from the Council of Canadian academies, if nothing else otherwise.

I’ve already featured these 2023 science events but just in case you missed them,

  • 2023 Preview: Bill Nye the Science Guy’s live show and Marvel Avengers S.T.A.T.I.O.N. (Scientific Training And Tactical Intelligence Operative Network) coming to Vancouver (Canada) November 24, 2022 posting
  • September 2023: Auckland, Aotearoa New Zealand set to welcome women in STEM (science, technology, engineering, and mathematics) November 15, 2022 posting

Getting back to this blog, it may not seem like a new year during the first few weeks of 2023 as I have quite the stockpile of draft posts. At this point I have drafts that are dated from June 2022 and expect to be burning through them so as not to fall further behind but will be interspersing them, occasionally, with more current posts.

Most importantly: a big thank you to everyone who drops by and reads (and sometimes even comments) on my posts!!! it’s very much appreciated and on that note: I wish you all the best for 2023.

Nanoparticles for prolonged anti-lice protection

Leave a reply
Caption Graphical abstract [the animal is a capybara, world’s largest rodent] Credit: Kazan Federal University, Louisiana Tech University, Gubkin University

A September 28, 2021Kazan Federal University (Russia) press release (also on EurekAlert; Source text: Larisa Busil Photo: Rawil Fakhrullin) announces news that could lead to relief for anyone who owns animals,

An international researcher team of Louisiana Tech University, Gubkin University [also known as, Gubkin Russian State University of Oil and Gas] and Kazan Federal University reported the fabrication of nanoscale insecticidal hair coating for prolonged anti-lice protection. The study was supported by the Russian Science Foundation.

“Treating agricultural and domestic animals infected with ectoparasites (such as lice, fleas, chewing lice, etc.) is among the primary challenges of veterinary medicine and agriculture. In case of mass infestation, regular measures, such as isolation of infected animals or repeated reapplication of insecticides, are not always effective. These methods are time-limited and provide a short-term therapeutic effect,” explains co-author Rawil Fakhrullin, Head of Kazan University’s Bionanotechnology Lab. “Using an inorganic nanoscale carrier as a component of a therapeutic formulation for topical application of insecticides might be the optimal way to address this challenge.”

Halloysite, a natural nanosized tubular mineral, was used as a drug carrier capable of forming a durable and uniform coating on the surface of animal hair.

“Loading an insecticidal drug, permethrin, into halloysite nanotubes reduces the release rate, leading to fewer re-treatments and fewer side effects,” continues Dr. Fakhrullin.

The paper shows that after goat hair samples were treated with halloysite-based nanocontainers, a stable 2-3 micron waterproof coating was formed on the surface of the hair, suitable for long-term antiparasitic protection.

“Long-term insecticidal activity is the result of the gradual release of the drug from the nanotubes. A formulation based on halloysite retains its protective antiparasitic properties after washing the animal’s hair with water. This stable and water-resistant composite coating provides a drug dose effective for long-term protection of animals,” says the interviewee.

The authors also examined the hair structure of the capybara, world’s largest rodent native to South America. They found that the wax-like layer present on the hair surface of this semi-aquatic animal facilitates the formation of a denser and more durable coating of halloysite than in terrestrial animals (guinea pigs and goats). The wax helps retaining nanoclay particles on the surface of the animal’s hair.

Dr. Fakhrullin comments about the test subjects, “We studied the suppressive effects of nanocontainers on goat ectoparasites Damalinia caprae from the Trichodectidae family. At the same time, our technique can be effective towards other types of lice, since these parasites live in hair and maintain close contact with hair cuticles, regardless of the animal’s dietary preferences. We believe that this approach can be used for long-term and sustainable antiparasitic protection of farm animals, especially if other insecticidal preparations are encapsulated in addition to permethrin. In addition, similar drugs can be used for the prevention or treatment of head lice in humans.”

Furthermore, the described material can also be helpful in treating fur in zoological collections.

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

Clay Nanotube Immobilization on Animal Hair for Sustained Anti-Lice Protection by Naureen Rahman, Faith Hannah Scott, Yuri Lvov, Anna Stavitskaya, Farida Akhatova, Svetlana Konnova, Gӧlnur Fakhrullina and Rawil Fakhrullin. Pharmaceutics 2021, 13(9), 1477; DOI: https://doi.org/10.3390/pharmaceutics13091477 Published: 15 September 2021

This paper is open access.

Boost single-walled carbon nantube (SWCNT) production

Leave a reply

I’m fascinated by this image,

Caption: Skoltech researchers have investigated the procedure for catalyst delivery used in the most common method of carbon nanotube production, chemical vapor deposition (CVD), offering what they call a “simple and elegant” way to boost productivity and pave the way for cheaper and more accessible nanotube-based technology. Credit: Pavel Odinev/Skoltech

If I understand it correctly, getting the catalyst particles into a tighter, more uniform formation is what could lead to a boost in the production of single-walled carbon nanotubes (SWCNTs).

The work was announced in a Nov. 30, 2020 news item in Nanowerk,

Skoltech [Skolkovo Institute of Science and Technology; Russia] researchers have investigated the procedure for catalyst delivery used in the most common method of carbon nanotube production, chemical vapor deposition (CVD), offering what they call a “simple and elegant” way to boost productivity and pave the way for cheaper and more accessible nanotube-based technology.

A Nov. 30, 2020 Skolkovo Institute of Science and Technology (Skoltech) press release (also on EurekAlert but published on Dec. 1, 2020), which originated the news item, explains in detail,

Single-walled carbon nanotubes (SWCNT), tiny rolled sheets of graphene with a thickness of just one atom, hold huge promise when it comes to applications in materials science and electronics. That is the reason why so much effort is focused on perfecting the synthesis of SWCNTs; from physical methods, such as using laser beams to ablate a graphite target, all the way to the most common CVD approach, when metal catalyst particles are used to “strip” a carbon-containing gas of its carbon and grow the nanotubes on these particles.

“The road from raw materials to carbon nanotubes requires a fine balance between dozens of reactor parameters. The formation of carbon nanotubes is a tricky and complex process that has been studied for a long time, but still keeps many secrets,” explains Albert Nasibulin, a professor at Skoltech and an adjunct professor at the Department of Chemistry and Materials Science, Aalto University School of Chemical Engineering.

Various ways of enhancing catalyst activation, in order to produce more SWCNTs with the required properties, have already been suggested. Nasibulin and his colleagues focused on the injection procedure, namely on how to distribute ferrocene vapor (a commonly used catalyst precursor) within the reactor.

They grew their carbon nanotubes using the aerosol CVD approach, using carbon monoxide as a source of carbon, and monitored the synthesis productivity and SWCNT characteristics (such as their diameter) depending on the rate of catalyst injection and the concentration of CO2 (carbon dioxide; used as an agent for fine-tuning). Ultimately the researchers concluded that “injector flow rate adjustment could lead to a 9-fold increase in the synthesis productivity while preserving most of the SWCNT characteristics”, such as their diameter, the share of defective nanotubes, and film conductivity.

“Every technology is always about efficiency. When it comes to CVD production of nanotubes, the efficiency of the catalyst is usually out of sight. However, we see a great opportunity there and this work is only a first step towards an efficient technology,” Dmitry Krasnikov, senior research scientist at Skoltech and co-author of the paper, says.

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

Activation of catalyst particles for single-walled carbon nanotube synthesis by Eldar M.Khabushev, Julia V. Kolodiazhnaia, Dmitry V. Krasnikov, Albert G. Nasibulin. Chemical Engineering Journal DOI: https://doi.org/10.1016/j.cej.2020.127475 Available online 24 October 2020, 127475

This paper is behind a paywall.

A robot that sucks up oil spills

Leave a reply

I was surprised to find out that between 1989 when the Exxon Valdez oil spill fouled the coastline along Alaska and northern British Columbia and 2010 when the BP (British Petroleum) oil spill fouled the Gulf of Mexico and a number of US states, which border it, and Mexico’s state coastlines, there had been virtually no improvement in the environmental remediation technologies for oil spills (see my June 4, 2010 posting).

This summer we’ve had two major oil spills, one in the Russian Arctic (as noted in my August 14, 2020 posting; scroll down to the subhead ‘As for the Russian Arctic oil spill‘) and in the Indian Ocean near Mauritius and near a coral reef and marine protected areas (see this August 13, 2020 news item on the Canadian Broadcasting Corporation [CBC] news online website).

No word yet on whether or not remediation techniques have improved but this August 6, 2020 article by Adele Peters for Fast Company highlights a new robotic approach to cleaning marine oil spills,

A decade after a BP drilling rig exploded in the Gulf of Mexico, sending an estimated 168 million gallons of oil gushing into the water over the course of months, local wildlife are still struggling to recover. Many of the people who worked to clean up the spill are still experiencing health effects. At the time, the “cleanup” strategy involved setting oil slicks on fire and spraying mass quantities of a chemical meant to disperse it, both of which helped get rid of the oil, but also worsened pollution [emphasis mine].

A new robot designed to clean oil spills, now in development, demonstrates how future spills could be handled differently. The robot navigates autonomously on the ocean surface, running on solar power. When oil sensors on the device detect a spill, it triggers a pump that pushes oil and water inside, where a custom nanomaterial sucks up the oil and releases clean water.

…

Kabra [Tejas Sanjay Kabra, a graduate student at North Carolina State University] 3D-printed a small prototype of the robot, which he tested in a lab, a swimming pool, and then the open ocean. (The small version, about two feet across, can collect 20 gallons of oil at a time; the same device can be scaled up to much larger sizes). He now hopes to bring the product to market as quickly as possible, as major oil spills continue to occur—such as the spill in Russia in June that sent more than 20,000 metric tons of diesel into a pristine part of the Arctic.

Peters’s article provides more details and features an embedded video.

Kabra calls his technology, SoilioS (Spilled OIL recovery by Isis & Oleophilic Sponge) and he entered it in the 2020 James Dyson Awards. The undated James Dyson Award news release announcing the 2020 national winners does not include Kabra’s entry. Mind you, over 1700 inventors entered the 2020 competition.

I hope Kabra perseveres as his robot project looks quite interesting for a number of reasons as can be seen in his entry submission (from the James Dyson Award website),

Initially, I started with a literature review on various Nanomaterials made from tree leaves with specific properties of Hydrophobicity and oleophilicity. Then I narrowed down my research on four different types of leaves i.e., Holy basil, betel, subabul, and mango. Nanoparticles from these leaves were made by green synthesis method and SEM, EDX and XRD tests were conducted. From these tests, I found that the efficiency of material made from the subabul tree was max (82.5%). In order to carry out surface cleaning at sea, different robot designs were studied. Initially, the robot was built in a box structure with arms. The arms contained Nano-capillary; however, the prototype was bulky and inefficient. A new model was devised to reduce the weight as well as increase the efficiency of absorbing the oil spill. The new robot was designed to be in a meta-stable state. The curves of the robot are designed in such a way that it gives stability as well as hold all the components. The top part of the robot is a hollow dome to improve the stability in water. The robot is 3D printed to reduce weight. The 3D printed robot was tested in a pool. Further, work is going on to build a 222 feet robot to test with hardware suitable for sea.

Here’s what SoilioS looks like,

[downloaded from https://www.jamesdysonaward.org/en-US/2020/project/soilios/]

Kabra described what makes his technology from what is currently the state-of-the-art and his future plans (from the James Dyson Award website),

The current technology uses carbon Nano-particle, and some other uses plastic PVC with a chemical adhesive, which is harmful to the environment. On the other hand, SoilioS uses Nano-material made from tree leaves. The invented technology absorbs the oil and stores inside the container with a recovery rate of 80%. The recovered oil can be used for further application; however, on the other hand, the current products burn the oil [emphasis mine] at the cleaning site itself without any recovery rate, thereby increasing pollution. The durability of the invented technology is 8-10 years, and the Nanomaterial used for cleaning the oil spill is reusable for 180 cycles. On the other hand, the durability of the current technology is up to 3-5 years, and the material used is non-reusable. The cost of the invented product is only $5 and on the other hand, the existing technology costs up to $750.

…

I aim to develop, manufacture, and practically test the robot prototype in the sea so that it can be used to solve oil spill issues and can save billions of dollars. I hope this device will help the environment in a lot of ways and eventually decrease the side effects caused due to oil spills such as leukemia and dying marine life. Currently, I am testing the product on different grades of oil to improve its efficiency further and improving its scope of the application so that it can also be used in industries and household purposes.

I wish Kabra good luck as he works to bring his technology to market.

Replacing nanotechnology-enabled oil spill solutions with dog fur?

Leave a reply

Coincidentally or not, this research from Australia was announced a little more than a month after reports of a major oil spill in the Russian Arctic. A July 10, 2020 news item on phys.org announces a new technology for mopping up oil spills (Note: Links have been removed),

Oil spill disasters on land cause long-term damage for communities and the natural environment, polluting soils and sediments and contaminating groundwater.

Current methods using synthetic sorbent materials can be effective for cleaning up oil spills, but these materials are often expensive and generate large volumes of non-biodegradable plastic wastes. Now the first comparison of natural-origin sorbent materials for land-based oil spills, including peat moss, recycled human hair, and dog fur, shows that sustainable, cheaper and biodegradable options can be developed.

The University of Technology Sydney (UTS) project found that dog fur and human hair products—recycled from salon wastes and dog groomers—can be just as good as synthetic fabrics at cleaning up crude oil spills on hard land surfaces like highway roads, pavement, and sealed concrete floors. Polypropylene, a plastic, is a widely-used fabric used to clean up oil spills in aquatic environments.

…

A July 9, 2020 Univesity of Technology Sydney press release on EurekAlert completes the story,

“Dog fur in particular was surprisingly good at oil spill clean-up, and felted mats from human hair and fur were very easy to apply and remove from the spills.” lead author of the study, UTS Environmental Scientist Dr Megan Murray, said. Dr Murray investigates environmentally-friendly solutions for contamination and leads The Phyto Lab research group at UTS School of Life Sciences.

“This is a very exciting finding for land managers who respond to spilled oil from trucks, storage tanks, or leaking oil pipelines. All of these land scenarios can be treated effectively with sustainable-origin sorbents,” she said.

The sorbents tested included two commercially-available products, propylene and loose peat moss, as well as sustainable-origin prototypes including felted mats made of dog fur and human hair. Prototype oil-spill sorbent booms filled with dog fur and human hair were also tested. Crude oil was used to replicate an oil spill. The results of the study are published in Environments.

The research team simulated three types of land surfaces; non-porous hard surfaces, semi-porous surfaces, and sand, to recreate common oil-spill scenarios.

“We found that loose peat moss is not as effective at cleaning up oil spills on land compared to dog fur and hair products, and it is not useful at all for sandy environments.” Dr Murray said.

“Based on this research, we recommend peat moss is no longer used for this purpose. Given that peat moss is a limited resource and harvesting it requires degrading wetland ecosystems, we think this is a very important finding.” she said.

The research concluded that, for now, sandy environments like coastal beaches can still benefit from the use of polypropylene sorbents, but further exploration of sustainable-origin sorbents is planned.

The researchers say that future applications from the research include investigating felted mats of sustainable-origin sorbents for river bank stabilisation, [emphases mine] as well as the removal of pollutants from flowing polluted waters, similar to existing membrane technology.

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

Decontaminating Terrestrial Oil Spills: A Comparative Assessment of Dog Fur, Human Hair, Peat Moss and Polypropylene Sorbents by Megan L. Murray, Soeren M. Poulsen and Brad R. Murray. Environments 2020, 7(7), 52; DOI: https://doi.org/10.3390/environments7070052 Published: 8 July 2020 (This article belongs to the Special Issue Pollution Prevention/Environmental Sustainability for Industry)

This paper is open access.

As for the Russian oil spill

A June 4, 2020 British Broadcasting Corporation (BBC) news online article outlines the situation regarding the oil spill and the steps being taken to deal with it,

Russia’s President Vladimir Putin has declared a state of emergency after 20,000 tonnes of diesel oil leaked into a river within the Arctic Circle.

The spill happened when a fuel tank at a power plant near the Siberian city of Norilsk collapsed last Friday [May 29, 2020].

The power plant’s director Vyacheslav Starostin has been taken into custody until 31 July, but not yet charged.

The plant is owned by a subsidiary of Norilsk Nickel, which is the world’s leading nickel and palladium producer.

The Russian Investigative Committee (SK) has launched a criminal case over the pollution and alleged negligence, as there was reportedly a two-day delay in informing the Moscow authorities about the spill.

Ground subsidence beneath the fuel storage tanks is believed to have caused the spill. Arctic permafrost has been melting in exceptionally warm weather [more information about the weather towards the end of this posting] for this time of year.

…

Russian Minister for Emergencies Yevgeny Zinichev told Mr Putin that the Norilsk plant had spent two days trying to contain the spill, before alerting his ministry.

The leaked oil drifted some 12km (7.5 miles) from the accident site, turning long stretches of the Ambarnaya river crimson red.

The leaked diesel oil drifted some 12km (7.5 miles) from the site of the accident [downloaded from https://www.bbc.com/news/world-europe-52915807]

Getting back to the June 4, 2020 British Broadcasting Corporation (BBC) news online article,

“Why did government agencies only find out about this two days [May 29, 2020?) after the fact?” he asked the subsidiary’s chief, Sergei Lipin. “Are we going to learn about emergency situations from social media?”

The region’s governor, Alexander Uss, had earlier told President Putin that he became aware of the oil spill on Sunday [May 31, 2020] after “alarming information appeared in social media”.

The spill has contaminated a 350 sq km (135 sq mile) area, state media report.

…

The state of emergency means extra forces are going to the area to assist with the clean-up operation.

The accident is believed to be the second largest in modern Russian history in terms of volume, an expert from the World Wildlife Fund, Alexei Knizhnikov, told the AFP [Agence France Presse] news agency.

The incident has prompted stark warnings from environmental groups, who say the scale of the spill and geography of the river mean it will be difficult to clean up.

Greenpeace has compared it to the 1989 Exxon Valdez disaster in Alaska.

Oleg Mitvol, former deputy head of Russia’s environmental watchdog Rosprirodnadzor, said there had “never been such an accident in the Arctic zone”.

He said the clean-up could cost 100bn roubles (£1.2bn; $1.5bn) and take between five and 10 years.

Minister of Natural Resources Dmitry Kobylkin warned against trying to burn off such a vast quantity of fuel oil.

He proposed trying to dilute the oil with reagents. Only the emergencies ministry with military support could deal with the pollution, he said.

Barges with booms could not contain the slick because the Ambarnaya river was too shallow, he warned.

He suggested pumping the oil on to the adjacent tundra, although President Putin added: “The soil there is probably saturated [with oil] already.”

An update of the situation can be found in a July 8, 2020 Canadian Broadcasting Corporation (CBC) article (issued by Thomson Reuters),

Russia’s environmental watchdog has asked a power subsidiary of Russian mining giant Norilsk Nickel to pay almost 148 billion rubles, or $2.8 billion Cdn, in damages over an Arctic fuel spill in Siberia.

Rosprirodnadzor, the Federal Service for Supervision of Use of Natural Resources, said in a statement on Monday [July 8, 2020] that it had already sent a request for “voluntary compensation” to the subsidiary, NTEK, after calculating the damage caused by the May 29 [2020] fuel spill.

Norilsk Nickel’s Moscow-listed shares fell by 3 per cent after the watchdog’s statement.

A fuel tank at the power plant lost pressure and released 21,000 tonnes of diesel into rivers and subsoil near the city of Norilsk, 2,900 kilometres northeast of Moscow. Russian President Vladimir Putin subsequently declared a state of emergency in the region, and investigators detained three staff at the power plant.

…

Norilsk, a remote city of 180,000 people situated 300 kilometres inside the Arctic Circle, is built around Norilsk Nickel, the world’s leading nickel and palladium producer, and has a reputation for its pollution.

Rosprirodnadzor said the damages included the cost for nearby water bodies, estimated at 147.05 billion rubles, $2.8 billion Cdn, and for subsoil, estimated at 738.62 million roubles, $14 million Cdn.

…

I can’t find any August 2020 updates for the oil spill situation in Russia. (Note: There is now an oil spill in a ecologically sensitive region near Mauritius; see August 13, 2020 news item on CBC news online website.)

Exceptionally warm weather

The oil spill isn’t the only problem in the Arctic.Here’s more from a June 23, 2020 article by Matt Simon for Wired magazine (Note: A link has been removed),

On Saturday [June 20, 2020], the residents of Verkhoyansk, Russia, marked the first day of summer with 100 degree Fahrenheit temperatures. Not that they could enjoy it, really, as Verkhoyansk is in Siberia, hundreds of miles from the nearest beach. That’s much, much hotter than towns inside the Arctic Circle usually get. That 100 degrees appears to be a record, well above the average June high temperature of 68 degrees. Yet it’s likely the people of Verkhoyansk will see that record broken again in their lifetimes: The Arctic is warming twice as fast as the rest of the planet—if not faster—creating ecological chaos for the plants and animals that populate the north.

“The events over the weekend—in the last few weeks, really—with the heatwave in Siberia, all are unprecedented in terms of the magnitude of the extremes in temperature,” says Sophie Wilkinson, a wildfire scientist at McMaster University who studies northern peat fires, which themselves have grown unusually frequent in recent years as temperatures climb.

The Arctic’s extreme warming, known as Arctic amplification or polar amplification, may be due to three factors. One, the region’s reflectivity, or albedo—how much light it bounces back into space—is changing as the world warms. “What we’ve been seeing over the last 30 years is some relatively dramatic declines in sea ice in the summertime,” says University of Edinburgh global change ecologist Isla Myers-Smith, who studies the Arctic.

Since ice is white, it reflects the sun’s energy, something you’re already probably familiar with when it comes to staying cool in the summer. If you had to pick the color of T-shirt to wear when going hiking on a hot day, she says, “most of us would pick the white T-shirt, because that’s going to reflect the sun’s heat off of our back.” Similarly, Myers-Smith says, “If the sea ice melts in the Arctic, that will remove that white surface off of the ocean, and what will be exposed is this darker ocean surface that will absorb more of the sun’s heat.”

…

If you’re interested in the environmental consequences of the warming of the Arctic, this is a very good article.

Finishing up, I wish the clean-up crews (in Russia and near Mauritius) all the best as they work in the midst of a pandemic, as well as, an environmental disaster (both the oil spill and the warming of the Arctic).

Second order memristor

Leave a reply

I think this is my first encounter with a second-order memristor. An August 28, 2019 news item on Nanowerk announces the research (Note: A link has been removed),

Researchers from the Moscow Institute of Physics and Technology [MIPT} have created a device that acts like a synapse in the living brain, storing information and gradually forgetting it when not accessed for a long time. Known as a second-order memristor, the new device is based on hafnium oxide and offers prospects for designing analog neurocomputers imitating the way a biological brain learns.

…

An August 28, 2019 MIPT press release (also on EurekAlert), which originated the news item, provides an explanation for neuromorphic computing (analog neurocomputers; brainlike computing), the difference between a first-order and second-order memristor, and an in depth view of the research,

Neurocomputers, which enable artificial intelligence, emulate the way the brain works. It stores data in the form of synapses, a network of connections between the nerve cells, or neurons. Most neurocomputers have a conventional digital architecture and use mathematical models to invoke virtual neurons and synapses.

Alternatively, an actual on-chip electronic component could stand for each neuron and synapse in the network. This so-called analog approach has the potential to drastically speed up computations and reduce energy costs.

The core component of a hypothetical analog neurocomputer is the memristor. The word is a portmanteau of “memory” and “resistor,” which pretty much sums up what it is: a memory cell acting as a resistor. Loosely speaking, a high resistance encodes a zero, and a low resistance encodes a one. This is analogous to how a synapse conducts a signal between two neurons (one), while the absence of a synapse results in no signal, a zero.

But there is a catch: In an actual brain, the active synapses tend to strengthen over time, while the opposite is true for inactive ones. This phenomenon known as synaptic plasticity is one of the foundations of natural learning and memory. It explains the biology of cramming for an exam and why our seldom accessed memories fade.

Proposed in 2015, the second-order memristor is an attempt to reproduce natural memory, complete with synaptic plasticity. The first mechanism for implementing this involves forming nanosized conductive bridges across the memristor. While initially decreasing resistance, they naturally decay with time, emulating forgetfulness.

“The problem with this solution is that the device tends to change its behavior over time and breaks down after prolonged operation,” said the study’s lead author Anastasia Chouprik from MIPT’s Neurocomputing Systems Lab. “The mechanism we used to implement synaptic plasticity is more robust. In fact, after switching the state of the system 100 billion times, it was still operating normally, so my colleagues stopped the endurance test.”

Instead of nanobridges, the MIPT team relied on hafnium oxide to imitate natural memory. This material is ferroelectric: Its internal bound charge distribution — electric polarization — changes in response to an external electric field. If the field is then removed, the material retains its acquired polarization, the way a ferromagnet remains magnetized.

The physicists implemented their second-order memristor as a ferroelectric tunnel junction — two electrodes interlaid with a thin hafnium oxide film (fig. 1, right). The device can be switched between its low and high resistance states by means of electric pulses, which change the ferroelectric film’s polarization and thus its resistance.

“The main challenge that we faced was figuring out the right ferroelectric layer thickness,” Chouprik added. “Four nanometers proved to be ideal. Make it just one nanometer thinner, and the ferroelectric properties are gone, while a thicker film is too wide a barrier for the electrons to tunnel through. And it is only the tunneling current that we can modulate by switching polarization.”

What gives hafnium oxide an edge over other ferroelectric materials, such as barium titanate, is that it is already used by current silicon technology. For example, Intel has been manufacturing microchips based on a hafnium compound since 2007. This makes introducing hafnium-based devices like the memristor reported in this story far easier and cheaper than those using a brand-new material.

In a feat of ingenuity, the researchers implemented “forgetfulness” by leveraging the defects at the interface between silicon and hafnium oxide. Those very imperfections used to be seen as a detriment to hafnium-based microprocessors, and engineers had to find a way around them by incorporating other elements into the compound. Instead, the MIPT team exploited the defects, which make memristor conductivity die down with time, just like natural memories.

Vitalii Mikheev, the first author of the paper, shared the team’s future plans: “We are going to look into the interplay between the various mechanisms switching the resistance in our memristor. It turns out that the ferroelectric effect may not be the only one involved. To further improve the devices, we will need to distinguish between the mechanisms and learn to combine them.”

According to the physicists, they will move on with the fundamental research on the properties of hafnium oxide to make the nonvolatile random access memory cells more reliable. The team is also investigating the possibility of transferring their devices onto a flexible substrate, for use in flexible electronics.

Last year, the researchers offered a detailed description of how applying an electric field to hafnium oxide films affects their polarization. It is this very process that enables reducing ferroelectric memristor resistance, which emulates synapse strengthening in a biological brain. The team also works on neuromorphic computing systems with a digital architecture.

MIPT has provided this image illustrating the research,

Caption: The left image shows a synapse from a biological brain, the inspiration behind its artificial analogue (right). The latter is a memristor device implemented as a ferroelectric tunnel junction — that is, a thin hafnium oxide film (pink) interlaid between a titanium nitride electrode (blue cable) and a silicon substrate (marine blue), which doubles up as the second electrode. Electric pulses switch the memristor between its high and low resistance states by changing hafnium oxide polarization, and therefore its conductivity. Credit: Elena Khavina/MIPT Press Office

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

Ferroelectric Second-Order Memristor by Vitalii Mikheev, Anastasia Chouprik, Yury Lebedinskii, Sergei Zarubin, Yury Matveyev, Ekaterina Kondratyuk, Maxim G. Kozodaev, Andrey M. Markeev, Andrei Zenkevich, Dmitrii Negrov. ACS Appl. Mater. Interfaces 2019113532108-32114 DOI: https://doi.org/10.1021/acsami.9b08189 Publication Date:August 12, 2019 Copyright © 2019 American Chemical Society

This paper is behind a paywall.

Memristor-based neural network and the biosimilar principle of learning

Leave a reply

Once you get past the technical language (there’s a lot of it), you’ll find that they make the link between biomimicry and memristors explicit. Admittedly I’m not an expert but if I understand the research correctly, the scientists are suggesting that the algorithms used in machine learning today cannot allow memristors to be properly integrated for use in true neuromorphic computing and this work from Russia and Greece points to a new paradigm. If you understand it differently, please do let me know in the comments.

A July 12, 2019 news item on Nanowerk kicks things off (Note: A link has been removed),

Lobachevsky University scientists together with their colleagues from the National Research Center “Kurchatov Institute” (Moscow) and the National Research Center “Demokritos” (Athens) are working on the hardware implementation of a spiking neural network based on memristors.

The key elements of such a network, along with pulsed neurons, are artificial synaptic connections that can change the strength (weight) of connection between neurons during the learning (Microelectronic Engineering, “Yttria-stabilized zirconia cross-point memristive devices for neuromorphic applications”).

For this purpose, memristive devices based on metal-oxide-metal nanostructures developed at the UNN Physics and Technology Research Institute (PTRI) are suitable, but their use in specific spiking neural network architectures developed at the Kurchatov Institute requires demonstration of biologically plausible learning principles.

…

Caption: Cross-section image of the metal-oxide-metal memristive structure based on ZrO2(Y) polycrystalline film (a); corresponding schematic view of the cross-point memristive device (b); STDP dependencies of memristive device conductance changes for different delay values between pre- and postsynaptic neuron spikes (c); photographs of a microchip and an array of memristive devices in a standard cermet casing (d); the simplest spiking neural network architecture learning on the basis of local rules for changing memristive weights (e). Credit: Lobachevsky University

A July 12, 2019 (?) Lobachevsky University press release (also on EurekAlert), which originated the news item, delves further into the work,

The biological mechanism of learning of neural systems is described by Hebb’s rule, according to which learning occurs as a result of an increase in the strength of connection  (synaptic weight) between simultaneously active neurons, which indicates the presence of a causal relationship in their excitation. One of the clarifying forms of this fundamental rule is plasticity, which depends on the time of arrival of pulses (Spike-Timing Dependent Plasticity – STDP).

In accordance with STDP, synaptic weight increases if the postsynaptic neuron generates a pulse (spike) immediately after the presynaptic one, and vice versa, the synaptic weight decreases if the postsynaptic neuron generates a spike right before the presynaptic one. Moreover, the smaller the time difference Δt between the pre- and postsynaptic spikes, the more pronounced the weight change will be.

According to one of the researchers, Head of the UNN PTRI laboratory Alexei Mikhailov, in order to demonstrate the STDP principle, memristive nanostructures based on yttria-stabilized zirconia (YSZ) thin films were used. YSZ is a well-known solid-state electrolyte with high oxygen ion mobility.

“Due to a specified concentration of oxygen vacancies, which is determined by the controlled concentration of yttrium impurities, and the heterogeneous structure of the films obtained by magnetron sputtering, such memristive structures demonstrate controlled bipolar switching between different resistive states in a wide resistance range. The switching is associated with the formation and destruction of conductive channels along grain boundaries in the polycrystalline ZrO2 (Y) film,” notes Alexei Mikhailov.

An array of memristive devices for research was implemented in the form of a microchip mounted in a standard cermet casing, which facilitates the integration of the array into a neural network’s analog circuit. The full technological cycle for creating memristive microchips is currently implemented at the UNN PTRI. In the future, it is possible to scale the devices down to the minimum size of about 50 nm, as was established by Greek partners.
Our studies of the dynamic plasticity of the memoristive devices, continues Alexey Mikhailov, have shown that the form of the conductance change depending on Δt is in good agreement with the STDP learning rules. It should be also noted that if the initial value of the memristor conductance is close to the maximum, it is easy to reduce the corresponding weight while it is difficult to enhance it, and in the case of a memristor with a minimum conductance in the initial state, it is difficult to reduce its weight, but it is easy to enhance it.

According to Vyacheslav Demin, director-coordinator in the area of nature-like technologies of the Kurchatov Institute, who is one of the ideologues of this work, the established pattern of change in the memristor conductance clearly demonstrates the possibility of hardware implementation of the so-called local learning rules. Such rules for changing the strength of synaptic connections depend only on the values ​​of variables that are present locally at each time point (neuron activities and current weights).

“This essentially distinguishes such principle from the traditional learning algorithm, which is based on global rules for changing weights, using information on the error values ​​at the current time point for each neuron of the output neural network layer (in a widely popular group of error back propagation methods). The traditional principle is not biosimilar, it requires “external” (expert) knowledge of the correct answers for each example presented to the network (that is, they do not have the property of self-learning). This principle is difficult to implement on the basis of memristors, since it requires controlled precise changes of memristor conductances, as opposed to local rules. Such precise control is not always possible due to the natural variability (a wide range of parameters) of memristors as analog elements,” says Vyacheslav Demin.

Local learning rules of the STDP type implemented in hardware on memristors provide the basis for autonomous (“unsupervised”) learning of a spiking neural network. In this case, the final state of the network does not depend on its initial state, but depends only on the learning conditions (a specific sequence of pulses). According to Vyacheslav Demin, this opens up prospects for the application of local learning rules based on memristors when solving artificial intelligence problems with the use of complex spiking neural network architectures.

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

Yttria-stabilized zirconia cross-point memristive devices for neuromorphic applications by A. V. Emelyanov, K. E. Nikiruy, A. Demin, V. V. Rylkov, A. I. Belov, D. S. Korolev, E. G. Gryaznov, D. A. Pavlov, O. N. Gorshkov, A. N. Mikhaylov, P. Dimitrakis. Microelectronic Engineering Volume 215, 15 July 2019, 110988 First available online 16 May 2019

This paper is behind a paywall.

Canadian researchers develop bone implant material from cellulose nanocrystals (CNC) while Russian scientists restore internal structure of bone with polycaprolactone nanofibers

Leave a reply

Two research groups are working to the same end where bone marrow is concerned, encourage bone cell growth, but they are using different strategies.

University of British Columbia and McMaster University (Canada)

Caption: Researchers treated nanocrystals derived from plant cellulose so that they can link up and form a strong but lightweight sponge (an aerogel) that can compress or expand as needed to completely fill out a bone cavity. Credit: Clare Kiernan, UBC

The samples look a little like teeth, don’t they?

Before diving into the research news, there’s a terminology issue that should be noted as you’ll see when you read the news/press releases. Nanocrystal cellulose/nanocrystalline cellulose (NCC) is a term coined by Canadian researchers. Since those early day, most researchers, internationally, have adopted the term cellulose nanocrystals (CNC) as the standard term. It fits better with the naming conventions for other nnanocellulose materials such as cellulose nanofibrils, etc. By the way, a Canadian company (CelluForce) that produces CNC retained the term nanocrystalline cellulose (NCC) as a trademark for the product, CelluForce NCC®.

For anyone not familiar with aerogels, what the University of British Columbia (UBC) and McMaster University researchers are developing, are also popularly known known as ‘frozen smoke’ (see the Aerogel Wikipedia entry for more).

A March 19, 2019 news item on ScienceDaily announces the research,

Researchers from the University of British Columbia and McMaster University have developed what could be the bone implant material of the future: an airy, foamlike substance that can be injected into the body and provide scaffolding for the growth of new bone.

It’s made by treating nanocrystals derived from plant cellulose so that they link up and form a strong but lightweight sponge — technically speaking, an aerogel — that can compress or expand as needed to completely fill out a bone cavity.

A March 19, 2019 UBC news release (also on EurekAlert), which originated the news item, describes the research in more detail,

“Most bone graft or implants are made of hard, brittle ceramic that doesn’t always conform to the shape of the hole, and those gaps can lead to poor growth of the bone and implant failure,” said study author Daniel Osorio, a PhD student in chemical engineering at McMaster. “We created this cellulose nanocrystal aerogel as a more effective alternative to these synthetic materials.”

For their research, the team worked with two groups of rats, with the first group receiving the aerogel implants and the second group receiving none. Results showed that the group with implants saw 33 per cent more bone growth at the three-week mark and 50 per cent more bone growth at the 12-week mark, compared to the controls.

“These findings show, for the first time in a lab setting, that a cellulose nanocrystal aerogel can support new bone growth,” said study co-author Emily Cranston, a professor of wood science and chemical and biological engineering who holds the President’s Excellence Chair in Forest Bio-products at UBC. She added that the implant should break down into non-toxic components in the body as the bone starts to heal.

The innovation can potentially fill a niche in the $2-billion bone graft market in North America, said study co-author Kathryn Grandfield, a professor of materials science and engineering, and biomedical engineering at McMaster who supervised the work.

“We can see this aerogel being used for a number of applications including dental implants and spinal and joint replacement surgeries,” said Grandfield. “And it will be economical because the raw material, the nanocellulose, is already being produced in commercial quantities.”

The researchers say it will be some time before the aerogel makes it out of the lab and into the operating room.

“This summer, we will study the mechanisms between the bone and implant that lead to bone growth,” said Grandfield. “We’ll also look at how the implant degrades using advanced microscopes. After that, more biological testing will be required before it is ready for clinical trials.”

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

Cross-linked cellulose nanocrystal aerogels as viable bone tissue scaffolds by Daniel A. Osorio, Bryan E. J. Lee, Jacek M. Kwiecien, Xiaoyue Wang, Iflah Shahid, Ariana L. Hurley, Emily D. Cranston and Kathryn Grandfield. Acta Biomaterialia Volume 87, 15 March 2019, Pages 152-165 DOI: https://doi.org/10.1016/j.actbio.2019.01.049

This paper is behind a paywall

Now for the Russian team.

National University of Science and Technology “MISIS” (formerly part of the Moscow Mining Academy)

These scientists have adopted a different strategy as you’ll see in the March 19, 2019 news item on Nanwerk, which, coincidentally, was published on the same day as the Canadian research,

Scientists from the National University of Science and Technology “MISIS” developed a nanomaterial, which will be able to rstore the internal structure of bones damaged due to osteoporosis and osteomyelitis. A special bioactive coating of the material helped to increase the rate of division of bone cells by 3 times. In the future, it can allow to abandon bone marrow transplantation and patients will no longer need to wait for suitable donor material.

A March 19, 2019 National University of Science and Technology (MISIS) press release (also on EurekAlert), which originated the news item, provides detail about the impetus for the research and the technique being developed,

Such diseases as osteoporosis and osteomyelitis cause irreversible degenerative changes in the bone structure. Such diseases require serious complex treatment and surgery and transplantation of the destroyed bone marrow in severe stages. Donor material should have a number of compatibility indicators and even close relationship with the donor cannot guarantee full compatibility.

Research group from the National University of Science and Technology “MISIS” (NUST MISIS), led by Anton Manakhov (Laboratory for Inorganic Nanomaterials) developed material that will allow to restore damaged internal bone structure without bone marrow transplantation.
It is based on nanofibers of polycaprolactone, which is biocompatible self-dissolvable material. Earlier, the same research group has already worked with this material: by adding antibiotics to the nanofibers, scientists have managed to create non-changeable healing bandages.

“If we want the implant to take, not only biocompatibility is needed, but also activation of the natural cell growth on the surface of the material. Polycaprolactone as such is a hydrophobic material, meaning, and cells feel uncomfortable on its surface. They gather on the smooth surface and divide extremely slow”, Elizaveta Permyakova, one of the co-authors and researcher at NUST MISIS Laboratory for Inorganic Nanomaterials, explains.

To increase the hydrophilicity of the material, a thin layer of bioactive film consisting of titanium, calcium, phosphorus, carbon, oxygen and nitrogen (TiCaPCON) was deposited on it. The structure of nanofibers identical to the cell surface was preserved. These films, when immersed in a special salt medium, which chemical composition is identical to human blood plasma, are able to form on its surface a special layer of calcium and phosphorus, which in natural conditions forms the main part of the bone. Due to the chemical similarity and the structure of nanofibers, new bone tissue begins to grow rapidly on this layer. Most importantly, polycaprolactone nanofibers dissolve, having fulfilled their functions. Only new “native” tissue remains in the bone.

In the experimental part of the study, the researchers compared the rate of division of osteoblastic bone cells on the surface of the modified and unmodified material. It was found that the modified material TiCaPCON has a high hydrophilicity. In contrast to the unmodified material, the cells on its surface felt clearly more comfortable, and divided three times faster.

According to scientists, such results open up great prospects for further work with modified polycaprolactone nanofibers as an alternative to bone marrow transplantation.

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

Bioactive TiCaPCON-coated PCL nanofibers as a promising material for bone tissue engineering by Anton Manakhov, Elizaveta S. Permyakova, Sergey Ershov, Alexander Sheveyko, Andrey Kovalskii, Josef Polčák, Irina Y. Zhitnyak, Natalia A. Gloushankova, Lenka Zajíčková, Dmitry V. Shtansky. Applied Surface Science Volume 479, 15 June 2019, Pages 796-802 DOI: https://doi.org/10.1016/j.apsusc.2019.02.163

This paper is behind a paywall.

Cellulose biosensor heralds new bioimaging approach to tissue engineering

Leave a reply

I keep an eye on how nanocellulose is being used in various applications and I’m not sure that this cellulose biosensor quite fits the bill as nanocellulose, nonetheless, it’s interesting and that’s enough for me. From a December 12, 2018 Sechenov University (Russia) press release on EurekAlert,

I.M. Sechenov First Moscow State Medical University teamed up together with Irish colleagues to develop a new imaging approach for tissue engineering. The team produced so-called ‘hybrid biosensor’ scaffold materials, which are based on cellulose matrices labeled with pH- and calcium-sensitive fluorescent proteins. These materials enable visualization of the metabolism and other important biomarkers in the engineered artificial tissues by microscopy. The results of the work were published in the Acta Biomaterialia journal.
The success of tissue engineering is based on the use of scaffold matrices – materials that support the viability and direct the growth of cells, tissues, and organoids. Scaffolds are important for basic and applied biomedical research, tissue engineering and regenerative medicine, and are promising for development of new therapeutics. However, the ability ‘to see’ what happens within the scaffolds during the tissue growth poses a significant research challenge

“We developed a new approach allowing visualization of scaffold-grown tissue and cells by using labeling with biosensor fluorescent proteins. Due to the high specificity of labeling and the use of fluorescence microscopy FLIM, we can quantify changes in pH and calcium in the vicinity of cells,” says Dr. Ruslan Dmitriev, Group Leader at the University College Cork and the Institute for Regenerative Medicine (I.M. Sechenov First Moscow State Medical University).
To achieve the specific labeling of cellulose matrices, researchers used well-known cellulose-binding proteins. The use of extracellular pH- and calcium-sensitive biosensors allow for analysis of cell metabolism: indeed, the extracellular acidification is directly associated with the balance of cell energy production pathways and the glycolytic flux (release of lactate). It is also a frequent hallmark of cancer and transformed cell types. On the other hand, calcium plays a key role in the extra- and intracellular signaling affecting cell growth and differentiation.

The approach was tested on different types of cellulose matrices (bacterial and produced from decellularised plant tissues) using 3D culture of human colon cancer cells and stem-cell derived mouse small intestinal organoids. The scaffolds informed on changes in the extracellular acidification and were used together with the analysis of real-time oxygenation of intestinal organoids. The resulting data can be presented in the form of colour maps, corresponding to the areas of cell growth within different microenvironments.

“Our results open new prospects in the imaging of tissue-engineered constructs for regenerative medicine. They enable deeper understanding of tissue metabolism in 3D and are also highly promising for commercialisation,” concludes Dr. Dmitriev.

The researchers have provided an image to illustrate their work,

Caption: A 3D reconstruction of a cellulose matrix stained with a pH-sensitive biosensor. Credit: Dr. R. Dmitriev

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

Cellulose-based scaffolds for fluorescence lifetime imaging-assisted tissue engineering by Neil O’Donnell, Irina A. Okkelman, Peter Timashev, Tatyana I.Gromovykh, Dmitri B. Papkovsky, Ruslan I.Dmitriev. Acta Biomaterialia Volume 80, 15 October 2018, Pages 85-96 DOI: https://doi.org/10.1016/j.actbio.2018.09.034


This paper is behind a paywall.

Two approaches to memristors

Leave a reply

Within one day of each other in October 2018, two different teams working on memristors with applications to neuroprosthetics and neuromorphic computing (brainlike computing) announced their results.

Russian team

An October 15, 2018 (?) Lobachevsky University press release (also published on October 15, 2018 on EurekAlert) describes a new approach to memristors,

Biological neurons are coupled unidirectionally through a special junction called a synapse. An electrical signal is transmitted along a neuron after some biochemical reactions initiate a chemical release to activate an adjacent neuron. These junctions are crucial for cognitive functions, such as perception, learning and memory.

A group of researchers from Lobachevsky University in Nizhny Novgorod investigates the dynamics of an individual memristive device when it receives a neuron-like signal as well as the dynamics of a network of analog electronic neurons connected by means of a memristive device. According to Svetlana Gerasimova, junior researcher at the Physics and Technology Research Institute and at the Neurotechnology Department of Lobachevsky University, this system simulates the interaction between synaptically coupled brain neurons while the memristive device imitates a neuron axon.

A memristive device is a physical model of Chua’s [Dr. Leon Chua, University of California at Berkeley; see my May 9, 2008 posting for a brief description Dr. Chua’s theory] memristor, which is an electric circuit element capable of changing its resistance depending on the electric signal received at the input. The device based on a Au/ZrO2(Y)/TiN/Ti structure demonstrates reproducible bipolar switching between the low and high resistance states. Resistive switching is determined by the oxidation and reduction of segments of conducting channels (filaments) in the oxide film when voltage with different polarity is applied to it. In the context of the present work, the ability of a memristive device to change conductivity under the action of pulsed signals makes it an almost ideal electronic analog of a synapse.

Lobachevsky University scientists and engineers supported by the Russian Science Foundation (project No.16-19-00144) have experimentally implemented and theoretically described the synaptic connection of neuron-like generators using the memristive interface and investigated the characteristics of this connection.

“Each neuron is implemented in the form of a pulse signal generator based on the FitzHugh-Nagumo model. This model provides a qualitative description of the main neurons’ characteristics: the presence of the excitation threshold, the presence of excitable and self-oscillatory regimes with the possibility of a changeover. At the initial time moment, the master generator is in the self-oscillatory mode, the slave generator is in the excitable mode, and the memristive device is used as a synapse. The signal from the master generator is conveyed to the input of the memristive device, the signal from the output of the memristive device is transmitted to the input of the slave generator via the loading resistance. When the memristive device switches from a high resistance to a low resistance state, the connection between the two neuron-like generators is established. The master generator goes into the oscillatory mode and the signals of the generators are synchronized. Different signal modulation mode synchronizations were demonstrated for the Au/ZrO2(Y)/TiN/Ti memristive device,” – says Svetlana Gerasimova.

UNN researchers believe that the next important stage in the development of neuromorphic systems based on memristive devices is to apply such systems in neuroprosthetics. Memristive systems will provide a highly efficient imitation of synaptic connection due to the stochastic nature of the memristive phenomenon and can be used to increase the flexibility of the connections for neuroprosthetic purposes. Lobachevsky University scientists have vast experience in the development of neurohybrid systems. In particular, a series of experiments was performed with the aim of connecting the FitzHugh-Nagumo oscillator with a biological object, a rat brain hippocampal slice. The signal from the electronic neuron generator was transmitted through the optic fiber communication channel to the bipolar electrode which stimulated Schaffer collaterals (axons of pyramidal neurons in the CA3 field) in the hippocampal slices. “We are going to combine our efforts in the design of artificial neuromorphic systems and our experience of working with living cells to improve flexibility of prosthetics,” concludes S. Gerasimova.

The results of this research were presented at the 38th International Conference on Nonlinear Dynamics (Dynamics Days Europe) at Loughborough University (Great Britain).

This diagram illustrates an aspect of the work,

Caption: Schematic of electronic neurons coupling via a memristive device. Credit: Lobachevsky University

US team

The American Institute of Physics (AIP) announced the publication of a ‘memristor paper’ by a team from the University of Southern California (USC) in an October 16, 2018 news item on phys.org,

Just like their biological counterparts, hardware that mimics the neural circuitry of the brain requires building blocks that can adjust how they synapse, with some connections strengthening at the expense of others. One such approach, called memristors, uses current resistance to store this information. New work looks to overcome reliability issues in these devices by scaling memristors to the atomic level.

An October 16, 2018 AIP news release (also on EurekAlert), which originated the news item, delves further into the particulars of this particular piece of memristor research,

A group of researchers demonstrated a new type of compound synapse that can achieve synaptic weight programming and conduct vector-matrix multiplication with significant advances over the current state of the art. Publishing its work in the Journal of Applied Physics, from AIP Publishing, the group’s compound synapse is constructed with atomically thin boron nitride memristors running in parallel to ensure efficiency and accuracy.

The article appears in a special topic section of the journal devoted to “New Physics and Materials for Neuromorphic Computation,” which highlights new developments in physical and materials science research that hold promise for developing the very large-scale, integrated “neuromorphic” systems of tomorrow that will carry computation beyond the limitations of current semiconductors today.

“There’s a lot of interest in using new types of materials for memristors,” said Ivan Sanchez Esqueda, an author on the paper. “What we’re showing is that filamentary devices can work well for neuromorphic computing applications, when constructed in new clever ways.”

Current memristor technology suffers from a wide variation in how signals are stored and read across devices, both for different types of memristors as well as different runs of the same memristor. To overcome this, the researchers ran several memristors in parallel. The combined output can achieve accuracies up to five times those of conventional devices, an advantage that compounds as devices become more complex.

The choice to go to the subnanometer level, Sanchez said, was born out of an interest to keep all of these parallel memristors energy-efficient. An array of the group’s memristors were found to be 10,000 times more energy-efficient than memristors currently available.

“It turns out if you start to increase the number of devices in parallel, you can see large benefits in accuracy while still conserving power,” Sanchez said. Sanchez said the team next looks to further showcase the potential of the compound synapses by demonstrating their use completing increasingly complex tasks, such as image and pattern recognition.

Here’s an image illustrating the parallel artificial synapses,

Caption: Hardware that mimics the neural circuitry of the brain requires building blocks that can adjust how they synapse. One such approach, called memristors, uses current resistance to store this information. New work looks to overcome reliability issues in these devices by scaling memristors to the atomic level. Researchers demonstrated a new type of compound synapse that can achieve synaptic weight programming and conduct vector-matrix multiplication with significant advances over the current state of the art. They discuss their work in this week’s Journal of Applied Physics. This image shows a conceptual schematic of the 3D implementation of compound synapses constructed with boron nitride oxide (BNOx) binary memristors, and the crossbar array with compound BNOx synapses for neuromorphic computing applications. Credit: Ivan Sanchez Esqueda

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

Efficient learning and crossbar operations with atomically-thin 2-D material compound synapses by Ivan Sanchez Esqueda, Huan Zhao and Han Wang. The article will appear in the Journal of Applied Physics Oct. 16, 2018 (DOI: 10.1063/1.5042468).

This paper is behind a paywall.

*Title corrected from ‘Two approaches to memristors featuring’ to ‘Two approaches to memristors’ on May 31, 2019 at 1455 hours PDT.