Tag Archives: Japan

Memristive spintronic neurons

A December 6, 2021 news item on Nanowerk on memristive spintronic neurons (Note: A link has been removed),

Researchers at Tohoku University and the University of Gothenburg have established a new spintronic technology for brain-inspired computing.

Their achievement was published in the journal Nature Materials (“Memristive control of mutual SHNO synchronization for neuromorphic computing”).

Sophisticated cognitive tasks, such as image and speech recognition, have seen recent breakthroughs thanks to deep learning. Even so, the human brain still executes these tasks without exerting much energy and with greater efficiency than any computer. The development of energy-efficient artificial neurons capable of emulating brain-inspired processes has therefore been a major research goal for decades.

A November 29, 2021 Tohoku University press release (also on EurekAlert but published November 30, 2021), which originated the news release, provides more technical detail,

Researchers demonstrated the first integration of a cognitive computing nano-element – the memristor – into another – a spintronic oscillator. Arrays of these memristor-controlled oscillators combine the non-volatile local storage of the memristor function with the microwave frequency computation of the nano-oscillator networks and can closely imitate the non-linear oscillatory neural networks of the human brain.

Resistance of the memristor changed with the voltage hysteresis applied to the top Ti/Cu electrode. Upon voltage application to the electrode, an electric field was applied at the high-resistance state, compared to electric current flows for the low-resistance state. The effects of electric field and current on the oscillator differed from each other, offering various controls of oscillation and synchronization properties.

Professor Johan Åkerman of the University of Gothenburg and leader of the study expressed his hopes for the future and the significance of the finding. “We are particularly interested in emerging quantum-inspired computing schemes, such as Ising Machines. The results also highlight the productive collaboration that we have established in neuromorphic spintronics between the University of Gothenburg and Tohoku University, something that is also part of the Sweden-Japan collaborative network MIRAI 2.0.”

“So far, artificial neurons and synapses have been developed separately in many fields; this work marks an important milestone: two functional elements have been combined into one,” said professor Shunsuke Fukami, who led the project on the Tohoku University side. Dr. Mohammad Zahedinejad of the University of Gothenburg and first author of the study adds, “Using the memristor-controlled spintronic oscillator arrays, we could tune the synaptic interactions between adjacent neurons and program them into mutually different and partially synchronized states.”

To put into practice their discovery, the researchers examined the operation of a test device comprising one oscillator and one memristor. The constricted region of W/CoFeB stack served as an oscillator, i.e., the neuron, whereas the MgO/AlOx/SiNx stack acted as a memristor, i.e., the synapse.

Resistance of the memristor changed with the voltage hysteresis applied to the top Ti/Cu electrode. Upon voltage application to the electrode, an electric field was applied at the high-resistance state, compared to electric current flows for the low-resistance state. The effects of electric field and current on the oscillator differed from each other, offering various controls of oscillation and synchronization properties.

Professor Johan Åkerman of the University of Gothenburg and leader of the study expressed his hopes for the future and the significance of the finding. “We are particularly interested in emerging quantum-inspired computing schemes, such as Ising Machines. The results also highlight the productive collaboration that we have established in neuromorphic spintronics between the University of Gothenburg and Tohoku University, something that is also part of the Sweden-Japan collaborative network MIRAI 2.0.” [sic]

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

Memristive control of mutual spin Hall nano-oscillator synchronization for neuromorphic computing by Mohammad Zahedinejad, Himanshu Fulara, Roman Khymyn, Afshin Houshang, Mykola Dvornik, Shunsuke Fukami, Shun Kanai, Hideo Ohno & Johan Åkerman. Nature Materials (2021) DOI: https://doi.org/10.1038/s41563-021-01153-6 Published 29 November 2021

This paper is behind a paywall.

Artificially designed protein nanoparticle TIP60

As is often the case with research from Japan, I find the work interesting and challenging to read about. An October 5, 2021 news item on Nanowerk describes the nature of the research from Japan,

Nanoparticles and nanocages are attractive materials that may be applied in color agents, catalysts, and drug delivery. For real-world use, it is necessary to produce a large number of nanoparticles of uniform size and shape, but thus far, nanoparticle formation methods using metals have been widely researched, and the formation of nanoparticles with a certain shape and size have been realized. However, it is not easy to create a group of uniform nanoparticles with the same structure at the atomic level.

You might find as I did that this image provided by the researchers is quite helpful (Thank you to the person who made this diagram),

Caption: Sixty fusion proteins of a pentameric Sm-like protein (PDB ID: 3BY7) and a dimeric MyoX-coil domain (PDB ID: 2LW9) self-assemble into a protein nanoparticle complex, TIP60 (Truncated Icosahedral Protein composed of 60-mer fusion proteins). Credit: Reproduced from Icosahedral 60-meric porous structure of designed supramolecular protein nanoparticle TIP60, Ryoichi Arai et al., Chem. Commun., 2021, with permission from the Royal Society of Chemistry.

An October 5, 2021 Shinshu University press release on EurekAlert, which originated the news item, provides further detail

A joint research group led by Associate Professor Ryoichi Arai (Institute for Biomedical Sciences and Faculty of Textile Science and Technology, Shinshu University) and Assistant Professor Norifumi Kawakami (Faculty of Science and Technology, Keio University) developed a uniform and useful supramolecular protein nanoparticle symmetrically self-assembled from fusion proteins of a pentameric protein domain and a dimeric protein domain. It is possible to modify the functionality by site-specific mutagenesis or chemical modification. This designed protein nanoparticle with a diameter of about 22 nm was named TIP60 (Truncated Icosahedral Protein composed of 60-mer fusion proteins) because it is formed by self-assembling 60-meric artificial fusion proteins shaped like a soccer ball (N. Kawakami et al., Angew. Chem. Int. Ed. 57, 12400–12404, 2018).

In the present study, the joint research group solved the detailed three-dimensional structure of the TIP60 using single-particle cryo-electron microscopy. A large amount of TIP60 was expressed in E. coli, and a purified sample was observed at the cryo-electron microscope facility operated by Prof. Masahide Kikkawa lab at the University of Tokyo. By performing single-particle analysis based on obtained image data, a three-dimensional map was reconstructed with a resolution of 3.3 Å. It was revealed that TIP60 forms hollow spherical nanoparticles as designed and has an icosahedral 60-meric structure with 20 triangular-like pores with an edge of about 4 nm each. In addition, the group elucidated in detail the characteristic three-dimensional structure, such as the linker connecting the pentamer formation domain and the dimer formation domain composed of an α-helix.

When a small molecule compound is added after chemically modifying only the outer surface of TIP60 with a high molecular compound, the small molecule compound enters the internal cavity and chemically modifies in the inner surface. In other words, it was found that the porous structure of TIP60 acts as a filter by molecular size, and the outer and inner surfaces of TIP60 can be chemically modified with different molecules of different sizes (E. Nasu et al., ACS Appl. Nano Mater. 4, 2434–2439, 2021).

In the future, the group will utilize artificially designed protein nanoparticles by advancing the design and functional modification of site-specific variants based on the three-dimensional structure of TIP60 elucidated in this study. It is expected to lead to the development and applications in the nanobiotechnology and nanomaterial fields, such as use as a nanocapsule for a drug delivery system

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

Icosahedral 60-meric porous structure of designed supramolecular protein nanoparticle TIP60 by Junya Obata, Norifumi Kawakami, Akihisa Tsutsumi, Erika Nasu, Kenji Miyamoto, Masahide Kikkawa and Ryoichi Arai. Chemical Communications (Chem. Commun., 2021,57, 10226-10229) DOI: https://doi.org/10.1039/D1CC03114G First published 04 Sep 2021

This paper is behind a paywall.

Cellulose nanofiber (CNF) coating protects plants against rust disease

A September 8, 2021news item on ScienceDaily describes some new research into rust disease,

A water-absorbent coat to keep rust away? It may seem counterintuitive but when it comes to soybean plants and rust disease, researchers from Japan have discovered that applying a coating that makes leaf surfaces water absorbent helps to protect against infection.

Caption: Researchers from the University of Tsukuba have found that coating soybean plant leaves with cellulose nanofiber (CNF) gives protection against an aggressive fungal disease. The CNF coating changed leaf surfaces from water repellent to water absorbent, and suppressed pathogen gene expression associated with infection mechanisms, offering resistance to the destructive Asian rust disease. This is the first study to examine CNF application for controlling plant diseases, and it offers a sustainable alternative to managing plant disease.. Credit: University of Tsukuba

A September 7, 2021 University of Tsukuba press release (also on EurekAlert but published September 8, 2021), which originated the news item, describes the disease and proposed solution in more detail,

In a study published this month in Frontiers in Plant Science, researchers from the University of Tsukuba have revealed that coating soybean plant leaves with cellulose nanofiber changes the leaf surface from water repellent to water absorbent and offers resistance against Asian soybean rust.

Rusts are plant diseases that get their name from the powdery rust- or brown-colored fungal spores on the surfaces of infected plants. Asian soybean rust (ASR) is an aggressive disease of soybean plants, causing estimated crop yield losses of up to 90%. ASR is caused by Phakopsora pachyrhizi, a fungal pathogen that requires a living plant host to survive. The timely application of fungicide is currently the only way of controlling ASR in the field. But the use of fungicides can be problematic, resulting in negative environmental effects, increased production costs, and fungicide-resistant pathogens.

“We investigated cellulose nanofiber (CNF) as an alternative method of controlling ASR,” says senior author of the study, Professor Yasuhiro Ishiga. “Specifically, we wanted to know whether coating soybean plant leaves with CNF protected plants against P. pachyrhizi.

Of the available methods for isolating CNF, aqueous counter collision (ACC) has been shown to alter the hydrophilic (water absorbent) and hydrophobic (water repellent) properties of surfaces, switching one to the other. Previous research has indicated that CNF obtained via ACC has higher wettability than CNF isolated by other methods.

“We showed that CNF can change the soybean leaf surface from hydrophobic to hydrophilic,” explains senior author, Professor Yuji Yamashita. “This offers resistance against P. pachyrhizi.”

The team found fewer lesions and significantly reduced formation of P. pachyrhizi appressoria, which are specialized pre-infection structures used to break through the outer surface of the host plant, on CNF-treated leaves compared with control (untreated) leaves. The results also revealed suppressed gene expression linked to the formation of pre-infection structures in P. pachyrhizi on treated versus control leaves.

“In particular, chitin synthase gene expression was suppressed, and P. pachyrhizi needs chitin synthases to form pre-infection structures,” says Professor Ishiga.

This study is the first to investigate the application of CNF for controlling plant diseases in the field, and this technique offers new possibilities for sustainable and eco-friendly management of plant diseases.

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

Covering Soybean Leaves With Cellulose Nanofiber Changes Leaf Surface Hydrophobicity and Confers Resistance Against Phakopsora pachyrhizi by
Haruka Saito, Yuji Yamashita, Nanami Sakata, Takako Ishiga, Nanami Shiraishi, Giyu Usuki, Viet Tru Nguyen, Eiji Yamamura and Yasuhiro Ishiga. Front. Plant Sci., 03 September 2021 DOI: https://doi.org/10.3389/fpls.2021.726565

This paper appears to be open access.

Science policy updates (INGSA in Canada and SCWIST)

I had just posted my Aug. 30, 2021 piece (4th International Conference on Science Advice to Governments (INGSA2021) August 30 – September 2, 2021) when the organization issued a news release, which was partially embargoed. By the time this is published (after 8 am ET on Wednesday, Sept. 1, 2021), the embargo will have lifted and i can announce that Rémi Quirion, Chief Scientist of Québec (Canada), has been selected to replace Sir Peter Gluckman (New Zealand) as President of INGSA.

Here’s the whole August 30, 2021 International Network for Government Science Advice (INGSA) news release on EurekAlert, Note: This looks like a direct translation from a French language news release, which may account for some unusual word choices and turns of phrase,

What? 4th International Conference on Science Advice to Governments, INGSA2021.

Where? Palais des Congrès de Montréal, Québec, Canada and online at www.ingsa2021.org

When? 30 August – 2 September, 2021.

CONTEXT: The largest ever independent gathering of interest groups, thought-leaders, science advisors to governments and global institutions, researchers, academics, communicators and diplomats is taking place in Montreal and online. Organized by Prof Rémi Quirion, Chief Scientist of Québec, speakers from over 50 countries[1] from Brazil to Burkina Faso and from Ireland to Indonesia, plus over 2000 delegates from over 130 countries, will spotlight what is really at stake in the relationship between science and policy-making, both during crises and within our daily lives. From the air we breathe, the food we eat and the cars we drive, to the medical treatments or the vaccines we take, and the education we provide to children, this relationship, and the decisions it can influence, matter immensely.  

Prof Rémi Quirion, Conference Organizer, Chief Scientist of Québec and incoming President of INGSA added: “For those of us who believe wholeheartedly in evidence and the integrity of science, the past 18 months have been challenging. Information, correct and incorrect, can spread like a virus. The importance of open science and access to data to inform our UN sustainable development goals discussions or domestically as we strengthen the role of cities and municipalities, has never been more critical. I have no doubt that this transparent and honest platform led from Montréal will act as a carrier-wave for greater engagement”.

Chief Science Advisor of Canada and Conference co-organizer, Dr Mona Nemer, stated that: “Rapid scientific advances in managing the Covid pandemic have generated enormous public interest in evidence-based decision making. This attention comes with high expectations and an obligation to achieve results. Overcoming the current health crisis and future challenges will require global coordination in science advice, and INGSA is well positioned to carry out this important work. Canada and our international peers can benefit greatly from this collaboration.”

Sir Peter Gluckman, founding Chair of INGSA stated that: “This is a timely conference as we are at a turning point not just in the pandemic, but globally in our management of longer-term challenges that affect us all. INGSA has helped build and elevate open and ongoing public and policy dialogue about the role of robust evidence in sound policy making”.

He added that: “Issues that were considered marginal seven years ago when the network was created are today rightly seen as central to our social, environmental and economic wellbeing. The pandemic highlights the strengths and weaknesses of evidence-based policy-making at all levels of governance. Operating on all continents, INGSA demonstrates the value of a well-networked community of emerging and experienced practitioners and academics, from countries at all levels of development. Learning from each other, we can help bring scientific evidence more centrally into policy-making. INGSA has achieved much since its formation in 2014, but the energy shown in this meeting demonstrates our potential to do so much more”.

Held previously in Auckland 2014, Brussels 2016, Tokyo 2018 and delayed for one year due to Covid, the advantage of the new hybrid and virtual format is that organizers have been able to involve more speakers, broaden the thematic scope and offer the conference as free to view online, reaching thousands more people. Examining the complex interactions between scientists, public policy and diplomatic relations at local, national, regional and international levels, especially in times of crisis, the overarching INGSA2021 theme is: “Build back wiser: knowledge, policy & publics in dialogue”.

The first three days will scrutinize everything from concrete case-studies outlining successes and failures in our advisory systems to how digital technologies and AI are reshaping the profession itself. The final day targets how expertize and action in the cultural context of the French-speaking world is encouraging partnerships and contributing to economic and social development. A highlight of the conference is the 2 September announcement of a new ‘Francophonie Science Advisory Network’.       

Prof. Salim Abdool Karim, a member of the World Health Organization’s Science Council, and the face of South Africa’s Covid-19 science, speaking in the opening plenary outlined that: “As a past anti-apartheid activist now providing scientific advice to policy-makers, I have learnt that science and politics share common features. Both operate at the boundaries of knowledge and uncertainty, but approach problems differently. We scientists constantly question and challenge our assumptions, constantly searching for empiric evidence to determine the best options. In contrast, politicians are most often guided by the needs or demands of voters and constituencies, and by ideology”.

He added: “What is changing is that grass-roots citizens worldwide are no longer ill-informed and passive bystanders. And they are rightfully demanding greater transparency and accountability. This has brought the complex contradictions between evidence and ideology into the public eye. Covid-19 is not just a disease, its social fabric exemplifies humanity’s interdependence in slowing global spread and preventing new viral mutations through global vaccine equity. This starkly highlights the fault-lines between the rich and poor countries, especially the maldistribution of life-saving public health goods like vaccines. I will explore some of the key lessons from Covid-19 to guide a better response to the next pandemic”.

Speaking on a panel analysing different advisory models, Prof. Mark Ferguson, Chair of the European Innovation Council’s Advisory Board and Chief Science Advisor to the Government of Ireland, sounded a note of optimism and caution in stating that: “Around the world, many scientists have become public celebrities as citizens engage with science like never before. Every country has a new, much followed advisory body. With that comes tremendous opportunities to advance the status of science and the funding of scientific research. On the flipside, my view is that we must also be mindful of the threat of science and scientists being viewed as a political force”.

Strength in numbers

What makes the 4th edition of this biennial event stand out is the perhaps never-before assembled range of speakers from all continents working at the boundary between science, society and policy willing to make their voices heard. In a truly ‘Olympics’ approach to getting all stakeholders on-board, organisers succeeded in involving, amongst others, the UN Office for Disaster Risk Reduction, the United Nations Development Programme, UNESCO and the OECD. The in-house science services of the European Commission and Parliament, plus many country-specific science advisors also feature prominently.

As organisers foster informed debate, we get a rare glimpse inside the science advisory worlds of the Comprehensive Nuclear Test Ban Treaty Organisation, the World Economic Forum and the Global Young Academy to name a few. From Canadian doctors, educators and entrepreneurs and charitable foundations like the Welcome Trust, to Science Europe and media organisations, the programme is rich in its diversity. The International Organisation of the Francophonie and a keynote address by H.E. Laurent Fabius, President of the Constitutional Council of the French Republic are just examples of two major draws on the final day dedicated to spotlighting advisory groups working through French. 

INGSA’s Elections: New Canadian President and Three Vice Presidents from Chile, Ethiopia, UK

The International Network for Government Science Advice has recently undertaken a series of internal reforms intended to better equip it to respond to the growing demands for support from its international partners, while realising the project proposals and ideas of its members.

Part of these reforms included the election in June, 2021 of a new President replacing Sir Peter Gluckman (2014 – 2021) and the creation of three new Vice President roles.

These results will be announced at 13h15 on Wednesday, 1st September during a special conference plenary and awards ceremony. While noting the election results below, media are asked to respect this embargo.

Professor Rémi Quirion, Chief Scientist of Québec (Canada), replaces Sir Peter Gluckman (New Zealand) as President of INGSA.
 

Professor Claire Craig (United Kingdom), CBE, Provost of Queen’s College Oxford and a member of the UK government’s AI Council, has been elected by members as the inaugural Vice President for Evidence.
 

Professor Binyam Sisay Mendisu (Egypt), PhD, Lecture at the University of Addis Ababa and Programme Advisor, UNESCO Institute for Building Capacity in Africa, has been elected by members as the inaugural Vice President for Capacity Building.
 

Professor Soledad Quiroz Valenzuela (Chile), Science Advisor on Climate Change to the Ministry of Science, Technology, Knowledge and Innovation of the government of Chile, has been elected by members as the Vice President for Policy.

Satellite Events: From 7 – 9 September, as part of INGSA2021, the conference is partnering with local,  national and international organisations to ignite further conversations about the science/policy/society interface. Six satellite events are planned to cover everything from climate science advice and energy policy, open science and publishing during a crisis, to the politicisation of science and pre-school scientific education. International delegates are equally encouraged to join in online. 

About INGSA: Founded in 2014 with regional chapters in Africa, Asia and Latin America and the Caribbean, INGSA has quicky established an important reputation as aa collaborative platform for policy exchange, capacity building and research across diverse global science advisory organisations and national systems. Currently, over 5000 individuals and institutions are listed as members. Science communicators and members of the media are warmly welcomed to join.

As the body of work detailed on its website shows (www.ingsa.org) through workshops, conferences and a growing catalogue of tools and guidance, the network aims to enhance the global science-policy interface to improve the potential for evidence-informed policy formation at sub-national, national and transnational levels. INGSA operates as an affiliated body of the International Science Council which acts as trustee of INGSA funds and hosts its governance committee. INGSA’s secretariat is based in Koi Tū: The Centre for Informed Futures at the University of Auckland in New Zealand.

Conference Programme: 4th International Conference on Science Advice to Government (ingsa2021.org)

Newly released compendium of Speaker Viewpoints: Download Essays From The Cutting Edge Of Science Advice – Viewpoints

[1] Argentina, Australia, Austria, Barbados, Belgium, Benin, Brazil, Burkina Faso, Cameroon, Canada, Chad, Colombia, Costa Rica, Côte D’Ivoire, Denmark, Estonia, Finland, France, Germany, Hong Kong, Indonesia, Ireland, Japan, Lebanon, Luxembourg, Malaysia, Mexico, Morocco, Netherlands, New Zealand, Pakistan, Papua New Guinea, Rwanda, Senegal, Singapore, Slovakia, South Africa, Spain, Sri Lanka, Sweden, Switzerland, Thailand, UK, USA. 

Society for Canadian Women in Science and Technology (SCWIST)

As noted earlier this year in my January 28, 2021 posting, it’s SCWIST’s 40th anniversary and the organization is celebrating with a number of initiatives, here are some of the latest including as talk on science policy (from the August 2021 newsletter received via email),

SCWIST “STEM Forward Project”
Receives Federal Funding

SCWIST’s “STEM Forward for Economic Prosperity” project proposal was among 237 projects across the country to receive funding from the $100 million Feminist Response Recovery Fund of the Government of Canada through the Women and Gender Equality Canada (WAGE) federal department.

Read more. 

iWIST and SCWIST Ink Affiliate MOU [memorandum of understanding]

Years in planning, the Island Women in Science and Technology (iWIST) of Victoria, British Columbia and SCWIST finally signed an Affiliate MOU (memorandum of understanding) on Aug 11, 2021.

The MOU strengthens our commitment to collaborate on advocacy (e.g. grants, policy and program changes at the Provincial and Federal level), events (networking, workshops, conferences), cross promotion ( event/ program promotion via digital media), and membership growth (discounts for iWIST members to join SCWIST and vice versa).

Dr. Khristine Carino, SCWIST President, travelled to Victoria to sign the MOU in person. She was invited as an honoured guest to the iWIST annual summer picnic by Claire Skillen, iWIST President. Khristine’s travel expenses were paid from her own personal funds.

Discovery Foundation x SBN x SCWIST Business Mentorship Program: Enhancing Diversity in today’s Biotechnology Landscape

The Discovery Foundation, Student Biotechnology Network, and Society for Canadian Women in Science and Technology are proud to bring you the first-ever “Business Mentorship Program: Enhancing Diversity in today’s Biotechnology Landscape”. 

The Business Mentorship Program aims to support historically underrepresented communities (BIPOC, Women, LGBTQIAS+ and more) in navigating the growth of the biotechnology industry. The program aims to foster relationships between individuals and professionals through networking and mentorship, providing education and training through workshops and seminars, and providing 1:1 consultation with industry leaders. Participants will be paired with mentors throughout the week and have the opportunity to deliver a pitch for the chance to win prizes at the annual Building Biotechnology Expo. 

This is a one week intensive program running from September 27th – October 1st, 2021 and is limited to 10 participants. Please apply early. 

Events

September 10

Art of Science and Policy-Making Go Together

Science and policy-making go together. Acuitas’ [emphasis mine] Molly Sung shares her journey and how more scientists need to engage in this important area.

September 23

Au-delà de l’apparence :

des femmes de courage et de résilience en STIM

Dans le cadre de la semaine de l’égalité des sexes au Canada, ce forum de la division québécoise de la Société pour les femmes canadiennes en science et technologie (la SCWIST) mettra en vedette quatre panélistes inspirantes avec des parcours variés qui étudient ou travaillent en science, technologie, ingénierie et mathématiques (STIM) au Québec. Ces femmes immigrantes ont laissé leurs proches et leurs pays d’origine pour venir au Québec et contribuer activement à la recherche scientifique québécoise. 

….

The ‘Art and Science Policy-Making Go Together’ talk seems to be aimed at persuasion and is not likely to offer any insider information as to how the BC life sciences effort is progressing. For a somewhat less rosy view of science and policy efforts, you can check out my August 23, 2021 posting, Who’s running the life science companies’ public relations campaign in British Columbia (Vancouver, Canada)?; scroll down to ‘The BC biotech gorillas’ subhead for more about Acuitas and some of the other life sciences companies in British Columbia (BC).

For some insight into how competitive the scene is here in BC, you can see my August 20, 2021 posting (Getting erased from the mRNA/COVID-19 story) about Ian MacLachlan.

You can check out more at the SCWIST website and I’m not sure when the August issue will be placed there but they do have a Newsletter Archive.

How do viruses and physics go together? Find out at a Nov. 4, 2020 Perimeter Institute (PI) virtual lecture

I got this announcement from an Oct. 29, 2020 Perimeter Institute (PI) Emmy Noether newsletter (received via email),

Catherne Beauchemin

A Physicist’s Adventures in Virology WEDNESDAY, NOVEMBER 4 at 7 pm ET [4 pm PT]

In recent years, there has been a rise in cynicism about many traditionally well-respected institutions – science, academia, news reporting, and even the concepts of experts and expertise more generally. Many people’s primary – or only – exposure to science is through biological or health science, especially during the COVID-19 pandemic.

In health research, rising cynicism has spawned the anti-vaccine movement, and a growing reliance on advice from peer networks rather than experts. In part, such movements are fuelled by several examples of provably false, so-called “scientific results,” coming about either through fraud or incompetence. While skepticism is crucial to science, cynicism rooted in a lack of trust can devalue scientific contributions.

In her lecture webcast, physicist Catherine Beauchemin will explore the erosion of trust in health research, presenting examples from influenza and COVID-19. …

I went to the A Physicist’s Adventures in Virology event and livestrream page to find this,

Two essential ingredients of the scientific method are skepticism and independent confirmation – the ability to glean for oneself whether an established theory or a new hypothesis is true or false. But not everyone has the capacity to perform the experiments to obtain such a confirmation.

Consider, for example, the costs of constructing your own Large Hadron Collider, or your ability as a non-expert to critically read and understand a scientific publication. In practice, acceptance of scientific theories is more often based on trust than on independent confirmation. When that trust is eroded, issues emerge.

Catherine Beauchemin is a Professor of Physics at Ryerson University and a Deputy Program Director in the RIKEN Interdisciplinary Theoretical and Mathematical Sciences Program in Japan. For the last 18 years, she has been developing mathematical and computational descriptions of how viruses spread from cell to cell, a field she calls “virophysics.”

In her November 4 [2020] Perimeter Public Lecture webcast, Beauchemin will highlight some of the issues that have eroded trust in health research, presenting examples from influenza and COVID-19. She will show why she believes many of these issues have their root in the fact that hypotheses in health research are formulated as words rather than mathematical expressions – and why a dose of physics may be just the prescription we need.

Enjoy!

Hydrogel (a soft, wet material) can memorize, retrieve, and forget information like a human brain

This is fascinating and it’s not a memristor. (You can find out more about memristors here on the Nanowerk website). Getting back to the research, scientists at Hokkaido University (Japan) are training squishy hydrogel to remember according to a July 28, 2020 news item on phys.org (Note: Links have been removed),

Hokkaido University researchers have found a soft and wet material that can memorize, retrieve, and forget information, much like the human brain. They report their findings in the journal Proceedings of the National Academy of Sciences (PNAS).

The human brain learns things, but tends to forget them when the information is no longer important. Recreating this dynamic memory process in manmade materials has been a challenge. Hokkaido University researchers now report a hydrogel that mimics the dynamic memory function of the brain: encoding information that fades with time depending on the memory intensity.

Hydrogels are flexible materials composed of a large percentage of water—in this case about 45%—along with other chemicals that provide a scaffold-like structure to contain the water. Professor Jian Ping Gong, Assistant Professor Kunpeng Cui and their students and colleagues in Hokkaido University’s Institute for Chemical Reaction Design and Discovery (WPI-ICReDD) are seeking to develop hydrogels that can serve biological functions.

“Hydrogels are excellent candidates to mimic biological functions because they are soft and wet like human tissues,” says Gong. “We are excited to demonstrate how hydrogels can mimic some of the memory functions of brain tissue.”

Caption: The hydrogel’s memorizing-forgetting behavior is achieved based on fast water uptake (swelling) at high temperature and slow water release (shrinking) at low temperature, which is enabled by dynamic bonds in the gel. The swelling part turns from transparent to opaque when cooled, enabling memory retrieval. (Chengtao Yu et al., PNAS, July 27, 2020) Credit: Chengtao Yu et al., PNAS, July 27, 2020

A July 27, 2020 Hokkaido University press release (also on EurekAlert but published July 28, 2020), which originated the news item, investigates just how the scientists trained the hydrogel,

In this study, the researchers placed a thin hydrogel between two plastic plates; the top plate had a shape or letters cut out, leaving only that area of the hydrogel exposed. For example, patterns included an airplane and the word “GEL.” They initially placed the gel in a cold water bath to establish equilibrium. Then they moved the gel to a hot bath. The gel absorbed water into its structure causing a swell, but only in the exposed area. This imprinted the pattern, which is like a piece of information, onto the gel. When the gel was moved back to the cold water bath, the exposed area turned opaque, making the stored information visible, due to what they call “structure frustration.” At the cold temperature, the hydrogel gradually shrank, releasing the water it had absorbed. The pattern slowly faded. The longer the gel was left in the hot water, the darker or more intense the imprint would be, and therefore the longer it took to fade or “forget” the information. The team also showed hotter temperatures intensified the memories.

“This is similar to humans,” says Cui. “The longer you spend learning something or the stronger the emotional stimuli, the longer it takes to forget it.”

The team showed that the memory established in the hydrogel is stable against temperature fluctuation and large physical stretching. More interestingly, the forgetting processes can be programmed by tuning the thermal learning time or temperature. For example, when they applied different learning times to each letter of “GEL,” the letters disappeared sequentially.

The team used a hydrogel containing materials called polyampholytes or PA gels. The memorizing-forgetting behavior is achieved based on fast water uptake and slow water release, which is enabled by dynamic bonds in the hydrogels. “This approach should work for a variety of hydrogels with physical bonds,” says Gong.

“The hydrogel’s brain-like memory system could be explored for some applications, such as disappearing messages for security,” Cui added.

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

Hydrogels as dynamic memory with forgetting ability by Chengtao Yu, Honglei Guo, Kunpeng Cui, Xueyu Li, Ya Nan Ye, Takayuki Kurokawa, and Jian Ping Gong. PNAS August 11, 2020 117 (32) 18962-18968 DOI: https://doi.org/10.1073/pnas.2006842117 First published July 27, 2020

This paper is behind a paywall.

Optical fibers made from marine algae

Apparently after you’ve finished imaging with your marine algae-based optical fibers, you can eat them. A July 24, 2020 news item on Nanowerk announces the new research,

An optical fiber made of agar has been produced at the University of Campinas (UNICAMP) in the state of São Paulo, Brazil. This device is edible, biocompatible and biodegradable. It can be used in vivo for body structure imaging, localized light delivery in phototherapy or optogenetics (e.g., stimulating neurons with light to study neural circuits in a living brain), and localized drug delivery.

Another possible application is the detection of microorganisms in specific organs, in which case the probe would be completely absorbed by the body after performing its function.

Caption: Edible, biocompatible and biodegradable, these fibers have potential for various medical applications. Credit: Eric Fujiwara

A July 24, 2020 Fundação de Amparo à Pesquisa dFundação de Amparo à Pesquisa do Estado de São Paulo (FAPESP) do Estado de São Paulo press release on EurekAlert, which originated the news item, provides a few more details about the researches and the work,

The research project, which was supported by São Paulo Research Foundation – FAPESP, was led by Eric Fujiwara, a professor in UNICAMP’s School of Mechanical Engineering, and Cristiano Cordeiro, a professor in UNICAMP’s Gleb Wataghin Institute of Physics, in collaboration with Hiromasa Oku, a professor at Gunma University in Japan.

An article on the study is published) in Scientific Reports, an online journal owned by Springer Nature.

Agar, also called agar-agar, is a natural gelatin obtained from marine algae. Its composition consists of a mixture of two polysaccharides, agarose and agaropectin. “Our optical fiber is an agar cylinder with an external diameter of 2.5 millimeters [mm] and a regular inner arrangement of six 0.5 mm cylindrical airholes around a solid core. Light is confined owing to the difference between the refraction indices of the agar core and the airholes,” Fujiwara told.

“To produce the fiber, we poured food-grade agar into a mold with six internal rods placed lengthwise around the main axis,” he continued. “The gel distributes itself to fill the available space. After cooling, the rods are removed to form airholes, and the solidified waveguide is released from the mold. The refraction index and geometry of the fiber can be adapted by varying the composition of the agar solution and mold design, respectively.”

The researchers tested the fiber in different media, from air and water to ethanol and acetone, concluding that it is context-sensitive. “The fact that the gel undergoes structural changes in response to variations in temperature, humidity and pH makes the fiber suitable for optical sensing,” Fujiwara said.

Another promising application is its simultaneous use as an optical sensor and a growth medium for microorganisms. “In this case, the waveguide can be designed as a disposable sample unit containing the necessary nutrients. The immobilized cells in the device would be optically sensed, and the signal would be analyzed using a camera or spectrometer,” he said.

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About São Paulo Research Foundation (FAPESP)

The São Paulo Research Foundation (FAPESP) is a public institution with the mission of supporting scientific research in all fields of knowledge by awarding scholarships, fellowships and grants to investigators linked with higher education and research institutions in the State of São Paulo, Brazil. FAPESP is aware that the very best research can only be done by working with the best researchers internationally. Therefore, it has established partnerships with funding agencies, higher education, private companies, and research organizations in other countries known for the quality of their research and has been encouraging scientists funded by its grants to further develop their international collaboration. You can learn more about FAPESP at http://www.fapesp.br/en and visit FAPESP news agency at http://www.agencia.fapesp.br/en to keep updated with the latest scientific breakthroughs FAPESP helps achieve through its many programs, awards and research centers. You may also subscribe to FAPESP news agency at http://agencia.fapesp.br/subscribe.

As per my usual practice, here’s a link to and a citation for the paper,

Agarose-based structured optical fibre by Eric Fujiwara, Thiago D. Cabral, Miko Sato, Hiromasa Oku & Cristiano M. B. Cordeiro. Scientific Reports volume 10, Article number: 7035 (2020) DOI: https://doi.org/10.1038/s41598-020-64103-3 Published: 27 April 2020

This paper is open access.

Should you have a problem accessing the English language version of the FAPESP website, the Portuguese language version of the site seems more accessible (assuming you have the language skills).

Improving neuromorphic devices with ion conducting polymer

A July 1, 2020 news item on ScienceDaily announces work which researchers are hopeful will allow them exert more control over neuromorphic devices’ speed of response,

“Neuromorphic” refers to mimicking the behavior of brain neural cells. When one speaks of neuromorphic computers, they are talking about making computers think and process more like human brains-operating at high-speed with low energy consumption.

Despite a growing interest in polymer-based neuromorphic devices, researchers have yet to establish an effective method for controlling the response speed of devices. Researchers from Tohoku University and the University of Cambridge, however, have overcome this obstacle through mixing the polymers PSS-Na and PEDOT:PSS, discovering that adding an ion conducting polymer enhances neuromorphic device response time.

A June 24, 2020 Tohoku University press release (also on EurekAlert), which originated the news item, provides a few more technical details,

Polymers are materials composed of long molecular chains and play a fundamental aspect in modern life from the rubber in tires, to water bottles, to polystyrene. Mixing polymers together results in the creation of new materials with their own distinct physical properties.

Most studies on neuromorphic devices based on polymer focus exclusively on the application of PEDOT: PSS, a mixed conductor that transports both electrons and ions. PSS-Na, on the other hand, transports ions only. By blending these two polymers, the researchers could enhance the ion diffusivity in the active layer of the device. Their measurements confirmed an increase in device response time, achieving a 5-time shorting at maximum. The results also proved how closely related response time is to the diffusivity of ions in the active layer.

“Our study paves the way for a deeper understanding behind the science of conducting polymers.” explains co-author Shunsuke Yamamoto from the Department of Biomolecular Engineering at Tohoku University’s Graduate School of Engineering. “Moving forward, it may be possible to create artificial neural networks composed of multiple neuromorphic devices,” he adds.

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

Controlling the Neuromorphic Behavior of Organic Electrochemical Transistors by Blending Mixed and Ion Conductors by Shunsuke Yamamoto and George G. Malliaras. ACS [American Chemical Society] Appl. Electron. Mater. 2020, XXXX, XXX, XXX-XXX DOI: https://doi.org/10.1021/acsaelm.0c00203 Publication Date:June 15, 2020 Copyright © 2020 American Chemical Society

This paper is behind a paywall.

Nanocellulose films made with liquid-phase fabrication method

I always appreciate a reference to Star Trek and three-dimensional chess was one of my favourite concepts. You’ll find that and more in a May 19, 2020 news item on Nanowerk,

Researchers at The Institute of Scientific and Industrial Research at Osaka University [Japan] introduced a new liquid-phase fabrication method for producing nanocellulose films with multiple axes of alignment. Using 3D-printing methods for increased control, this work may lead to cheaper and more environmentally friendly optical and thermal devices.

Ever since appearing on the original Star Trek TV show in the 1960s, the game of “three-dimensional chess” has been used as a metaphor for sophisticated thinking. Now, researchers at Osaka University can say that they have added their own version, with potential applications in advanced optics and inexpensive smartphone displays.

It’s not exactly three-dimensional chess but this nanocellulose film was produced by 3D printing methods,

Caption: Developed multiaxis nanocellulose-oriented film. Credit: Osaka University

A May 20, 2020 Osaka University press release (also on EurekAlert but dated May 19, 2020), which originated the news item, provides more detail,

Many existing optical devices, including liquid-crystal displays (LCDs) found in older flat-screen televisions, rely on long needle-shaped molecules aligned in the same direction. However, getting fibers to line up in multiple directions on the same device is much more difficult. Having a method that can reliably and cheaply produce optical fibers would accelerate the manufacture of low-cost displays or even “paper electronics”–computers that could be printed from biodegradable materials on demand.

Cellulose, the primary component of cotton and wood, is an abundant renewable resource made of long molecules. Nanocelluloses are nanofibers made of uniaxially aligned cellulose molecular chains that have different optical and heat conduction properties along one direction compared to the another.

In newly published research from the Institute of Scientific and Industrial Research at Osaka University, nanocellulose was harvested from sea pineapples, a kind of sea squirt. They then used liquid-phase 3D-pattering, which combined the wet spinning of nanofibers with the precision of 3D-printing. A custom-made triaxial robot dispensed a nanocellulose aqueous suspension into an acetone coagulation bath.

“We developed this liquid-phase three-dimensional patterning technique to allow for nanocellulose alignment along any preferred axis,” says first author Kojiro Uetani. The direction of the patterns could be programmed so that it formed an alternating checkerboard pattern of vertically- and horizontally-aligned fibers.

To demonstrate the method, a film was sandwiched between two orthogonal polarizing films. Under the proper viewing conditions, a birefringent checkerboard pattern appeared. They also measured the thermal transfer and optical retardation properties.

“Our findings could aid in the development of next-generation optical materials and paper electronics,” says senior author Masaya Nogi. “This could be the start of bottom-up techniques for building sophisticated and energy-efficient optical and thermal materials.”

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

Checkered Films of Multiaxis Oriented Nanocelluloses by Liquid-Phase Three-Dimensional Patterning by Kojiro Uetani, Hirotaka Koga and Masaya Nogi. Nanomaterials 2020, 10(5), 958; DOI: https://doi.org/10.3390/nano10050958 Published: 18 May 2020

This is an open access paper.