Tag Archives: Australia

Taxonomies (classification schemes) rouse passions

There seems to have been some lively debate among biologists about matters most of us treat as invisible: naming, establishing, and classifying categories. These activities can become quite visible when learning a new language, e.g., French which divides nouns into two genders or German which classifies nouns with any of three genders.

A July 26, 2020 essay by Stephen Garnett (Professor of Conservation and Sustainable Livelihoods, Charles Darwin University, Australia), Les Christidis (Professor, Southern Cross University, Australia), Richard L. Pyle (Associate lecturer, University of Hawaii, US), and Scott Thomson (Research associate, Universidade de São Paulo, Brazil) for The Conversation (also on phys.org but published July 27, 2020) describes a very heated debate over taxonomy,

Taxonomy, or the naming of species, is the foundation of modern biology. It might sound like a fairly straightforward exercise, but in fact it’s complicated and often controversial.

Why? Because there’s no one agreed list of all the world’s species. Competing lists exist for organisms such as mammals and birds, while other less well-known groups have none. And there are more than 30 definitions of what constitutes a species [emphasis mine]. This can make life difficult for biodiversity researchers and those working in areas such as conservation, biosecurity and regulation of the wildlife trade.

In the past few years, a public debate erupted among global taxonomists, including those who authored and contributed to this article, about whether the rules of taxonomy should be changed. Strongly worded ripostes were exchanged. A comparison to Stalin [emphasis mine] was floated.

Here’s how it started,

In May 2017 two of the authors, Stephen Garnett and Les Christidis, published an article in Nature. They argued taxonomy needed rules around what should be called a species, because currently there are none. They wrote:

” … for a discipline aiming to impose order on the natural world, taxonomy (the classification of complex organisms) is remarkably anarchic […] There is reasonable agreement among taxonomists that a species should represent a distinct evolutionary lineage. But there is none about how a lineage should be defined.

‘Species’ are often created or dismissed arbitrarily, according to the individual taxonomist’s adherence to one of at least 30 definitions. Crucially, there is no global oversight of taxonomic decisions — researchers can ‘split or lump’ species with no consideration of the consequences.”

Garnett and Christidis proposed that any changes to the taxonomy of complex organisms be overseen by the highest body in the global governance of biology, the International Union of Biological Sciences (IUBS), which would “restrict […] freedom of taxonomic action.”

… critics rejected the description of taxonomy as “anarchic”. In fact, they argued there are detailed rules around the naming of species administered by groups such as the International Commission on Zoological Nomenclature and the International Code of Nomenclature for algae, fungi, and plants. For 125 years, the codes have been almost universally adopted by scientists.

So in March 2018, 183 researchers – led by Scott Thomson and Richard Pyle – wrote an animated response to the Nature article, published in PLoS Biology [PLoS is Public Library of Science; it is an open access journal].

They wrote that Garnett and Christidis’ IUBS proposal was “flawed in terms of scientific integrity […] but is also untenable in practice”. They argued:

“Through taxonomic research, our understanding of biodiversity and classifications of living organisms will continue to progress. Any system that restricts such progress runs counter to basic scientific principles, which rely on peer review and subsequent acceptance or rejection by the community, rather than third-party regulation.”

In a separate paper, another group of taxonomists accused Garnett and Christidis of trying to suppress freedom of scientific thought, likening them to Stalin’s science advisor Trofim Lysenko.

The various parties did come together,

We hope by 2030, a scientific debate that began with claims of anarchy might lead to a clear governance system – and finally, the world’s first endorsed global list of species.

As for how they got to a “clear governance system”, there’s the rest of the July 26, 2020 essay on The Conversation or there’s the copy on phys.org (published July 27, 2020).

Replacing nanotechnology-enabled oil spill solutions with dog fur?

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).

Improving bacteria detection with the ‘unboil an egg’ machine

Vortex Fluidic Device (VFD) is the technical name for the more familiarly known ‘unboil an egg machine’ and, these days, it’s being used in research to improve bacteria detection. A June 23, 2020 news item on Nanowerk announces the research (Note: A link has been removed),

The versatility of the Vortex Fluidic Device (VFD), a device that famously unboiled an egg, continues to impress, with the innovative green chemistry device created at Flinders University having more than 100 applications – including the creation of a new non-toxic fluorescent dye that detects bacteria harmful to humans.

Traditional fluorescent dyes to examine bacteria viability are toxic and suffer poor photostability – but using the VFD has enabled the preparation of a new generation of aggregation-induced emission dye (AIE) luminogens using graphene oxide (GO), thanks to collaborative research between Flinders University’s Institute for NanoScale Science and Technology and the Centre for Health Technologies, University of Technology Sydney.

Using the VFD to produce GO/AIE probes with the property of high fluorescence is without precedent – with the new GO/AIE nanoprobe having 1400% brighter high fluorescent performance than AIE luminogen alone (Materials Chemistry Frontiers, “Vortex fluidic enabling and significantly boosting light intensity of graphene oxide with aggregation induced emission luminogen”).

A June 24, 2020 Flinders University [Australia] press release, which originated the news item, delves further into the work,

“It’s crucial to develop highly sensitive ways of detecting bacteria that pose a potential threat to humans at the early stage, so health sectors and governments can be informed promptly, to act quickly and efficiently,” says Flinders University researcher Professor Youhong Tang.

“Our GO/AIE nanoprobe will significantly enhance long-term tracking of bacteria to effectively control hospital infections, as well as developing new and more efficient antibacterial compounds.”

The VFD is a new type of chemical processing tool, capable of instigating chemical reactivity, enabling the controlled processing of materials such as mesoporous silica, and effective in protein folding under continuous flow, which is important in the pharmaceutical industry. It continues to impress researchers for its adaptability in green chemistry innovations.

“Developing such a deep understanding of bacterial viability is important to revise infection control policies and invent effective antibacterial compounds,” says lead author of the research, Dr Javad Tavakoli, a previous researcher from Professor Youhong Tang’s group, and now working at the University of Technology Sydney.

“The beauty of this research was developing a highly bright fluorescence dye based on graphene oxide, which has been well recognised as an effective fluorescence quenching material.”

The type of AIE luminogen was first developed in 2015 to enable long-term monitoring of bacterial viability, however, increasing its brightness to increase sensitivity and efficiency remained a difficult challenge. Previous attempts to produce AIE luminogen with high brightness proved very time-consuming, requires complex chemistry, and involves catalysts rendering their mass production expensive.

By comparison, the Vortex Fluidic Device allows swift and efficient processing beyond batch production and the potential for cost-effective commercialisation.

Increasing the fluorescent property of GO/AIE depends on the concentration of graphene oxide, the rotation speed of the VFD tube, and the water fraction in the compound – so preparing GO/AIE under the shear stress induced by the VFD’s high-speed rotating tube resulted in much brighter probes with significantly enhanced fluorescent intensities.

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

Vortex fluidic enabling and significantly boosting light intensity of graphene oxide with aggregation induced emission luminogen by Javad Tavakoli, Nikita Joseph, Clarence Chuah, Colin L. Raston and Youhong Tang. Mater. Chem. Front., [Materials Chemistry Frontiers] 2020, Advance Article DOI: https://doi.org/10.1039/D0QM00270D First published: 28 May 2020

This paper is behind a paywall.

I first marveled about the VFD (unboil an egg machine) in a March 16, 2016 posting.

Preventing warmed-up vaccines from becoming useless

One of the major problems with vaccines is that they need to be refrigerated. (The Nanopatch, which additionally wouldn’t require needles or syringes, is my favourite proposed solution and it comes from Australia.) This latest research into making vaccines more long-lasting is from the UK and takes a different approach to the problem.

From a June 8, 2020 news item on phys.org,

Vaccines are notoriously difficult to transport to remote or dangerous places, as they spoil when not refrigerated. Formulations are safe between 2°C and 8°C, but at other temperatures the proteins start to unravel, making the vaccines ineffective. As a result, millions of children around the world miss out on life-saving inoculations.

However, scientists have now found a way to prevent warmed-up vaccines from degrading. By encasing protein molecules in a silica shell, the structure remains intact even when heated to 100°C, or stored at room temperature for up to three years.

The technique for tailor-fitting a vaccine with a silica coat—known as ensilication—was developed by a Bath [University] team in collaboration with the University of Newcastle. This pioneering technology was seen to work in the lab two years ago, and now it has demonstrated its effectiveness in the real world too.

Here’s the lead researcher describing her team’s work

Ensilication: success in animal trials from University of Bath on Vimeo.

A June 8, 2020 University of Bath press release (also on EurekAlert) fills in more details about the research,

In their latest study, published in the journal Scientific Reports, the researchers sent both ensilicated and regular samples of the tetanus vaccine from Bath to Newcastle by ordinary post (a journey time of over 300 miles, which by post takes a day or two). When doses of the ensilicated vaccine were subsequently injected into mice, an immune response was triggered, showing the vaccine to be active. No immune response was detected in mice injected with unprotected doses of the vaccine, indicating the medicine had been damaged in transit.

Dr Asel Sartbaeva, who led the project from the University of Bath’s Department of Chemistry, said: “This is really exciting data because it shows us that ensilication preserves not just the structure of the vaccine proteins but also the function – the immunogenicity.”

“This project has focused on tetanus, which is part of the DTP (diphtheria, tetanus and pertussis) vaccine given to young children in three doses. Next, we will be working on developing a thermally-stable vaccine for diphtheria, and then pertussis. Eventually we want to create a silica cage for the whole DTP trivalent vaccine, so that every child in the world can be given DTP without having to rely on cold chain distribution.”

Cold chain distribution requires a vaccine to be refrigerated from the moment of manufacturing to the endpoint destination.

Silica is an inorganic, non-toxic material, and Dr Sartbaeva estimates that ensilicated vaccines could be used for humans within five to 15 years. She hopes the technology to silica-wrap proteins will eventually be adopted to store and transport all childhood vaccines, as well as other protein-based products, such as antibodies and enzymes.

“Ultimately, we want to make important medicines stable so they can be more widely available,” she said. “The aim is to eradicate vaccine-preventable diseases in low income countries by using thermally stable vaccines and cutting out dependence on cold chain.”

Currently, up to 50% of vaccine doses are discarded before use due to exposure to suboptimal temperatures. According to the World Health Organisation (WHO), 19.4 million infants did not receive routine life-saving vaccinations in 2018.

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

Ensilicated tetanus antigen retains immunogenicity: in vivo study and time-resolved SAXS characterization by A. Doekhie, R. Dattani, Y-C. Chen, Y. Yang, A. Smith, A. P. Silve, F. Koumanov, S. A. Wells, K. J. Edler, K. J. Marchbank, J. M. H. van den Elsen & A. Sartbaeva. Scientific Reports volume 10, Article number: 9243 (2020) DOI: https://doi.org/10.1038/s41598-020-65876-3 Published 08 June 2020

This paper is open access

Nanopatch update

I tend to lose track as a science gets closer to commercialization since the science news becomes business news and I almost never scan that sector. It’s been about two-and-half years since I featured research that suggested Nanopatch provided more effective polio vaccination than the standard needle and syringe method in a December 20, 2017 post. The latest bits of news have an interesting timeline.

March 2020

Mark Kendal (Wikipedia entry) is the researcher behind the Nanopatch. He’s interviewed in a March 5, 2020 episode (about 20 mins.) in the Pioneers Series (bankrolled by Rolex [yes, the watch company]) on Monocle.com. Coincidentally or not, a new piece of research funded by Vaxxas (the nanopatch company founded by Mark Kendall; on the website you will find a ‘front’ page and a ‘Contact us’ page only) was announced in a March 17, 2020 news item on medical.net,

Vaxxas, a clinical-stage biotechnology company commercializing a novel vaccination platform, today announced the publication in the journal PLoS Medicine of groundbreaking clinical research indicating the broad immunological and commercial potential of Vaxxas’ novel high-density microarray patch (HD-MAP). Using influenza vaccine, the clinical study of Vaxxas’ HD-MAP demonstrated significantly enhanced immune response compared to vaccination by needle/syringe. This is the largest microarray patch clinical vaccine study ever performed.

“With vaccine coated onto Vaxxas HD-MAPs shown to be stable for up to a year at 40°C [emphasis mine], we can offer a truly differentiated platform with a global reach, particularly into low and middle income countries or in emergency use and pandemic situations,” said Angus Forster, Chief Development and Operations Officer of Vaxxas and lead author of the PLoS Medicine publication. “Vaxxas’ HD-MAP is readily fabricated by injection molding to produce a 10 x 10 mm square with more than 3,000 microprojections that are gamma-irradiated before aseptic dry application of vaccine to the HD-MAP’s tips. All elements of device design, as well as coating and QC, have been engineered to enable small, modular, aseptic lines to make millions of vaccine products per week.”

The PLoS publication reported results and analyses from a clinical study involving 210 clinical subjects [emphasis mine]. The clinical study was a two-part, randomized, partially double-blind, placebo-controlled trial conducted at a single Australian clinical site. The clinical study’s primary objective was to measure the safety and tolerability of A/Singapore/GP1908/2015 H1N1 (A/Sing) monovalent vaccine delivered by Vaxxas HD-MAP in comparison to an uncoated Vaxxas HD-MAP and IM [intramuscular] injection of a quadrivalent seasonal influenza vaccine (QIV) delivering approximately the same dose of A/Sing HA protein. Exploratory outcomes were: to evaluate the immune responses to HD-MAP application to the forearm with A/Sing at 4 dose levels in comparison to IM administration of A/Sing at the standard 15 μg HA per dose per strain, and to assess further measures of immune response through additional assays and assessment of the local skin response via punch biopsy of the HD-MAP application sites. Local skin response, serological, mucosal and cellular immune responses were assessed pre- and post-vaccination.

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

Safety, tolerability, and immunogenicity of influenza vaccination with a high-density microarray patch: Results from a randomized, controlled phase I clinical trial by Angus H. Forster, Katey Witham, Alexandra C. I. Depelsenaire, Margaret Veitch, James W. Wells, Adam Wheatley, Melinda Pryor, Jason D. Lickliter, Barbara Francis, Steve Rockman, Jesse Bodle, Peter Treasure, Julian Hickling, Germain J. P. Fernando. DOI: https://doi.org/10.1371/journal.pmed.1003024 PLOS (Public Library of Science) Published: March 17, 2020

This is an open access paper.

May 2020

Two months later, Merck, an American multinational pharmaceutical company, showed some serious interest in the ‘nanopatch’. A May 28, 2020 article by Chris Newmarker for drugdelvierybusiness.com announces the news (Note: Links have been removed),

Merck has exercised its option to use Vaxxas‘ High Density Microarray Patch (HD-MAP) platform as a delivery platform for a vaccine candidate, the companies announced today [Thursday, May 28, 2020].

Also today, Vaxxas announced that German manufacturing equipment maker Harro Höfliger will help Vaxxas develop a high-throughput, aseptic manufacturing line to make vaccine products based on Vaxxas’ HD-MAP technology. Initial efforts will focus on having a pilot line operating in 2021 to support late-stage clinical studies — with a goal of single, aseptic-based lines being able to churn out 5 million vaccine products a week.

“A major challenge in commercializing microarray patches — like Vaxxas’ HD-MAP — for vaccination is the ability to manufacture at industrially-relevant scale, while meeting stringent sterility and quality standards. Our novel device design along with our innovative vaccine coating and quality verification technologies are an excellent fit for integration with Harro Höfliger’s aseptic process automation platforms. Adopting a modular approach, it will be possible to achieve output of tens-of-millions of vaccine-HD-MAP products per week,” Hoey [David L. Hoey, President and CEO of Vaxxas] said.

Vaxxas also claims that the patches can deliver vaccine more efficiently — a positive when people around the world are clamoring for a vaccine against COVID-19. The company points to a recent [March 17, 2020] clinical study in which their micropatch delivering a sixth of an influenza vaccine dose produced an immune response comparable to a full dose by intramuscular injection. A two-thirds dose by HD-MAP generated significantly faster and higher overall antibody responses.

As I noted earlier, this is an interesting timeline.

Final comment

In the end, what all of this means is that there may be more than one way to deal with vaccines and medicines that deteriorate all too quickly unless refrigerated. I wish all of these researchers the best.

Sunscreens 2020 and the Environmental Working Group (EWG)

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

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

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

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

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

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

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

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

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

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

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

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

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

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

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

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

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

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

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

The new guide also includes lists of:

Here are more quick tips for choosing better sunscreens:

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

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

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

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

History and politics of metallic nanoparticles in sunscreens

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

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

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

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

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

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

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

Research

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

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

EWG’s Wikipedia entry

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

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

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

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

American Experience

The Rockefellers Chapter One

Clip: Season 13 Episode 1 | 9m 37s

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

Fun in the sun

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

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

A tangle of silver nanowires for brain-like action

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

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

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

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

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

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

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

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

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

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

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

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

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

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

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

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

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

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

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

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

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

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

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

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

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

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

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

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

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

Emergent dynamics of neuromorphic nanowire networks by Adrian Diaz-Alvarez, Rintaro Higuchi, Paula Sanz-Leon, Ido Marcus, Yoshitaka Shingaya, Adam Z. Stieg, James K. Gimzewski, Zdenka Kuncic & Tomonobu Nakayama. Scientific Reports volume 9, Article number: 14920 (2019) DOI: https://doi.org/10.1038/s41598-019-51330-6 Published: 17 October 2019

This paper is open access.

Get better protection from a sunscreen with a ‘flamenco dancing’ molecule?

Caption: illustrative image for the University of Warwick research on ‘Flamenco dancing’ molecule could lead to better-protecting sunscreen created by Dr. Michael Horbury. Credit:: created by Dr Michael Horbury

There are high hopes (more about why later) for a plant-based ‘flamenco dancing molecule’ and its inclusion in sunscreens as described in an October 18, 2019 University of Warwick press release (also on EurekAlert),

A molecule that protects plants from overexposure to harmful sunlight thanks to its flamenco-style twist could form the basis for a new longer-lasting sunscreen, chemists at the University of Warwick have found, in collaboration with colleagues in France and Spain. Research on the green molecule by the scientists has revealed that it absorbs ultraviolet light and then disperses it in a ‘flamenco-style’ dance, making it ideal for use as a UV filter in sunscreens.

The team of scientists report today, Friday 18th October 2019, in the journal Nature Communications that, as well as being plant-inspired, this molecule is also among a small number of suitable substances that are effective in absorbing light in the Ultraviolet A (UVA) region of wavelengths. It opens up the possibility of developing a naturally-derived and eco-friendly sunscreen that protects against the full range of harmful wavelengths of light from the sun.

The UV filters in a sunscreen are the ingredients that predominantly provide the protection from the sun’s rays. In addition to UV filters, sunscreens will typically also include:

Emollients, used for moisturising and lubricating the skin
Thickening agents
Emulsifiers to bind all the ingredients
Water
Other components that improve aesthetics, water resistance, etc.

The researchers tested a molecule called diethyl sinapate, a close mimic to a molecule that is commonly found in the leaves of plants, which is responsible for protecting them from overexposure to UV light while they absorb visible light for photosynthesis.

They first exposed the molecule to a number of different solvents to determine whether that had any impact on its (principally) light absorbing behaviour. They then deposited a sample of the molecule on an industry standard human skin mimic (VITRO-CORNEUM®) where it was irradiated with different wavelengths of UV light. They used the state-of-the-art laser facilities within the Warwick Centre for Ultrafast Spectroscopy to take images of the molecule at extremely high speeds, to observe what happens to the light’s energy when it’s absorbed in the molecule in the very early stages (millionths of millionths of a second). Other techniques were also used to establish longer term (many hours) properties of diethyl sinapate, such as endocrine disruption activity and antioxidant potential.

Professor Vasilios Stavros from the University of Warwick, Department of Chemistry, who was part of the research team, explains: “A really good sunscreen absorbs light and converts it to harmless heat. A bad sunscreen is one that absorbs light and then, for example, breaks down potentially inducing other chemistry that you don’t want. Diethyl sinapate generates lots of heat, and that’s really crucial.”

When irradiated the molecule absorbs light and goes into an excited state but that energy then has to be disposed of somehow. The team of researchers observed that it does a kind of molecular ‘dance’ a mere 10 picoseconds (ten millionths of a millionth of a second) long: a twist in a similar fashion to the filigranas and floreos hand movements of flamenco dancers. That causes it to come back to its original ground state and convert that energy into vibrational energy, or heat.

It is this ‘flamenco dance’ that gives the molecule its long-lasting qualities. When the scientists bombarded the molecule with UVA light they found that it degraded only 3% over two hours, compared to the industry requirement of 30%.

Dr Michael Horbury, who was a Postgraduate Research Fellow at The University Warwick when he undertook this research (and now at the University of Leeds) adds: “We have shown that by studying the molecular dance on such a short time-scale, the information that you gain can have tremendous repercussions on how you design future sunscreens.
Emily Holt, a PhD student in the Department of Chemistry at the University of Warwick who was part of the research team, said: “The next step would be to test it on human skin, then to mix it with other ingredients that you find in a sunscreen to see how those affect its characteristics.”

Professor Florent Allais and Dr Louis Mouterde, URD Agro-Biotechnologies Industrielles at AgroParisTech (Pomacle, France) commented: “What we have developed together is a molecule based upon a UV photoprotective molecule found in the surface of leaves on a plant and refunctionalised it using greener synthetic procedures. Indeed, this molecule has excellent long-term properties while exhibiting low endocrine disruption and valuable antioxidant properties.”

Professor Laurent Blasco, Global Technical Manager (Skin Essentials) at Lubrizol and Honorary Professor at the University of Warwick commented: “In sunscreen formulations at the moment there is a lack of broad-spectrum protection from a single UV filter. Our collaboration has gone some way towards developing a next generation broad-spectrum UV filter inspired by nature. Our collaboration has also highlighted the importance of academia and industry working together towards a common goal.”

Professor Vasilios Stavros added, “Amidst escalating concerns about their impact on human toxicity (e.g. endocrine disruption) and ecotoxicity (e.g. coral bleaching), developing new UV filters is essential. We have demonstrated that a highly attractive avenue is ‘nature-inspired’ UV filters, which provide a front-line defence against skin cancer and premature skin aging.”

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

Towards symmetry driven and nature inspired UV filter design by Michael D. Horbury, Emily L. Holt, Louis M. M. Mouterde, Patrick Balaguer, Juan Cebrián, Laurent Blasco, Florent Allais & Vasilios G. Stavros. Nature Communications volume 10, Article number: 4748 (2019) DOI: https://doi.org/10.1038/s41467-019-12719-z

This paper is open access.

Why the high hopes?

Briefly (the long story stretches over 10 years), the most recommended sunscreens today (2020) are ‘mineral-based’. This is painfully amusing because civil society groups (activists) such as Friends of the Earth (in particular the Australia chapter under Georgia Miller’s leadership) and Canada’s own ETC Group had campaigned against these same sunscreen when they were billed as being based on metal oxide nanoparticles such zinc oxide and/or titanium oxide. The ETC Group under Pat Roy Mooney’s leadership didn’t press the campaign after an initial push. As for Australia and Friend of the Earth, their anti-metallic oxide nanoparticle sunscreen campaign didn’t work out well as I noted in a February 9, 2012 posting and with a follow-up in an October 31, 2012 posting.

The only civil society group to give approval (very reluctantly) was the Environmental Working Group (EWG) as I noted in a July 9, 2009 posting. They had concerns about the fact that these ingredients are metallic but after a thorough of then available research, EWG gave the sunscreens a passing grade and noted, in their report, that they had more concerns about the use of oxybenzone in sunscreens. That latter concern has since been flagged by others (e.g., the state of Hawai’i) as noted in my July 6, 2018 posting.

So, rebranding metallic oxides as minerals has allowed the various civil society groups to support the very same sunscreens many of them were advocating against.

In the meantime, scientists continue work on developing plant-based sunscreens as an improvement to the ‘mineral-based’ sunscreens used now.

Quantum processor woven from light

Weaving a quantum processor from light is a jaw-dropping event (as far as I’m concerned). An October 17, 2019 news item on phys.org makes the announcement,

An international team of scientists from Australia, Japan and the United States has produced a prototype of a large-scale quantum processor made of laser light.

Based on a design ten years in the making, the processor has built-in scalability that allows the number of quantum components—made out of light—to scale to extreme numbers. The research was published in Science today [October 18, 2019; Note: I cannot explain the discrepancy between the dates]].

Quantum computers promise fast solutions to hard problems, but to do this they require a large number of quantum components and must be relatively error free. Current quantum processors are still small and prone to errors. This new design provides an alternative solution, using light, to reach the scale required to eventually outperform classical computers on important problems.

Caption: The entanglement structure of a large-scale quantum processor made of light. Credit: Shota Yokoyama 2019

An October 18, 2019 RMIT University (Australia) press release (also on EurekAlert but published October 17, 2019), which originated the news time, expands on the theme,

“While today’s quantum processors are impressive, it isn’t clear if the current designs can be scaled up to extremely large sizes,” notes Dr Nicolas Menicucci, Chief Investigator at the Centre for Quantum Computation and Communication Technology (CQC2T) at RMIT University in Melbourne, Australia.

“Our approach starts with extreme scalability – built in from the very beginning – because the processor, called a cluster state, is made out of light.”

Using light as a quantum processor

A cluster state is a large collection of entangled quantum components that performs quantum computations when measured in a particular way.

“To be useful for real-world problems, a cluster state must be both large enough and have the right entanglement structure. In the two decades since they were proposed, all previous demonstrations of cluster states have failed on one or both of these counts,” says Dr Menicucci. “Ours is the first ever to succeed at both.”

To make the cluster state, specially designed crystals convert ordinary laser light into a type of quantum light called squeezed light, which is then weaved into a cluster state by a network of mirrors, beamsplitters and optical fibres.

The team’s design allows for a relatively small experiment to generate an immense two-dimensional cluster state with scalability built in. Although the levels of squeezing – a measure of quality – are currently too low for solving practical problems, the design is compatible with approaches to achieve state-of-the-art squeezing levels.

The team says their achievement opens up new possibilities for quantum computing with light.

“In this work, for the first time in any system, we have made a large-scale cluster state whose structure enables universal quantum computation.” Says Dr Hidehiro Yonezawa, Chief Investigator, CQC2T at UNSW Canberra. “Our experiment demonstrates that this design is feasible – and scalable.”

###

The experiment was an international effort, with the design developed through collaboration by Dr Menicucci at RMIT, Dr Rafael Alexander from the University of New Mexico and UNSW Canberra researchers Dr Hidehiro Yonezawa and Dr Shota Yokoyama. A team of experimentalists at the University of Tokyo, led by Professor Akira Furusawa, performed the ground-breaking experiment.

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

Generation of time-domain-multiplexed two-dimensional cluster state by Warit Asavanant, Yu Shiozawa, Shota Yokoyama, Baramee Charoensombutamon, Hiroki Emura, Rafael N. Alexander, Shuntaro Takeda, Jun-ichi Yoshikawa, Nicolas C. Menicucci, Hidehiro Yonezawa, Akira Furusawa. Science 18 Oct 2019: Vol. 366, Issue 6463, pp. 373-376 DOI: 10.1126/science.aay2645

This paper is behind a paywall.

The latest math stars: honeybees!

Understanding the concept of zero—I still remember climbing that mountain, so to speak. It took the teacher quite a while to convince me that representing ‘nothing’ as a zero was worthwhile. In fact, it took the combined efforts of both my parents and the teacher to convince me to use zeroes as I was prepared to go without. The battle is long since over and I have learned to embrace zero.

I don’t think bees have to be convinced but they too may have a concept of zero. More about that later, here’s the latest abut bees and math from an October 10, 2019 news item on phys.org,

Start thinking about numbers and they can become large very quickly. The diameter of the universe is about 8.8×1023 km and the largest known number—googolplex, 1010100—outranks it enormously. Although that colossal concept was dreamt up by brilliant mathematicians, we’re still pretty limited when it comes to assessing quantities at a glance. ‘Humans have a threshold limit for instantly processing one to four elements accurately’, says Adrian Dyer from RMIT University, Australia; and it seems that we are not alone. Scarlett Howard from RMIT and the Université de Toulouse, France, explains that guppies, angelfish and even honeybees are capable of distinguishing between quantities of three and four, although the trusty insects come unstuck at finer differences; they fail to differentiate between four and five, which made her wonder. According to Howard, honeybees are quite accomplished mathematicians. ‘Recently, honeybees were shown to learn the rules of “less than” and “greater than” and apply these rules to evaluate numbers from zero to six’, she says. Maybe numeracy wasn’t the bees’ problem; was it how the question was posed? The duo publishes their discovery that bees can discriminate between four and five if the training procedure is correct in Journal of Experimental Biology.

An October 10, 2019 The Company of Biologists’ press release on EurekAlert, which originated the news item, refines the information with more detail,

Dyer explains that when animals are trained to distinguish between colours and objects, some training procedures simply reward the animals when they make the correct decision. In the case of the honeybees that could distinguish three from four, they received a sip of super-sweet sugar water when they made the correct selection but just a taste of plain water when they got it wrong. However, Dyer, Howard and colleagues Aurore Avarguès-Weber, Jair Garcia and Andrew Greentree knew there was an alternative strategy. This time, the bees would be given a bitter-tasting sip of quinine-flavoured water when they got the answer wrong. Would the unpleasant flavour help the honeybees to focus better and improve their maths?

‘[The] honeybees were very cooperative, especially when I was providing sugar rewards’, says Howard, who moved to France each April to take advantage the northern summer during the Australian winter, when bees are dormant. Training the bees to enter a Y-shaped maze, Howard presented the insects with a choice; a card featuring four shapes in one arm and a card featuring a different number of shapes (ranging from one to 10) in the other. During the first series of training sessions, Howard rewarded the bees with a sugary sip when they alighted correctly before the card with four shapes, in contrast to a sip of water when they selected the wrong card. However, when Howard trained a second set of bees she reproved them with a bitter-tasting sip of quinine when they chose incorrectly, rewarding the insects with sugar when they selected the card with four shapes. Once the bees had learned to pick out the card with four shapes, Howard tested whether they could distinguish the card with four shapes when offered a choice between it and cards with eight, seven, six or – the most challenging comparison – five shapes.

Not surprisingly, the bees that had only been rewarded during training struggled; they couldn’t even differentiate between four and eight shapes. However, when Howard tested the honeybees that had been trained more rigorously – receiving a quinine reprimand – their performance was considerably better, consistently picking the card with four shapes when offered a choice between it and cards with seven or eight shapes. Even more impressively, the bees succeeded when offered the more subtle choice between four and five shapes.

So, it seems that honeybees are better mathematicians than had been credited. Unlocking their ability was simply a matter of asking the question in the right way and Howard is now keen to find out just how far counting bees can go.

I’ll get to the link to and citation for the paper in a minute but first, I found more about bees and math (including zero) in this February 7, 2019 article by Jason Daley for The Smithsonian (Note: Links have been removed),

Bees are impressive creatures, powering entire ecosystems via pollination and making sweet honey at the same time, one of the most incredible substances in nature. But it turns out the little striped insects are also quite clever. A new study suggests that, despite having tiny brains, bees understand the mathematical concepts of addition and subtraction.

To test the numeracy of the arthropods, researchers set up unique Y-shaped math mazes for the bees to navigate, according to Nicola Davis at the The Guardian. Because the insects can’t read, and schooling them to recognize abstract symbols like plus and minus signs would be incredibly difficult, the researchers used color to indicate addition or subtraction. …

Fourteen bees spent between four and seven hours completing 100 trips through the mazes during training exercises with the shapes and numbers chosen at random. All of the bees appeared to learn the concept. Then, the bees were tested 10 times each using two addition and two subtraction scenarios that had not been part of the training runs. The little buzzers got the correct answer between 64 and 72 percent of the time, better than would be expected by chance.

Last year, the same team of researchers published a paper suggesting that bees could understand the concept of zero, which puts them in an elite club of mathematically-minded animals that, at a minimum, have the ability to perceive higher and lower numbers in different groups. Animals with this ability include frogs, lions, spiders, crows, chicken chicks, some fish and other species. And these are not the only higher-level skills that bees appear to possess. A 2010 study that Dyer [Adrian Dyer of RMIT University in Australia] also participated in suggests that bees can remember human faces using the same mechanisms as people. Bees also use a complex type of movement called the waggle dance to communicate geographical information to one other, another sophisticated ability packed into a brain the size of a sesame seed.

If researchers could figure out how bees perform so many complicated tasks with such a limited number of neurons, the research could have implications for both biology and technology, such as machine learning. …

Then again, maybe the honey makers are getting more credit than they deserve. Clint Perry, who studies invertebrate intelligence at the Bee Sensory and Behavioral Ecology Lab at Queen Mary University of London tells George Dvorsky at Gizmodo that he’s not convinced by the research, and he had similar qualms about the study that suggested bees can understand the concept of zero. He says the bees may not be adding and subtracting, but rather are simply looking for an image that most closely matches the initial one they see, associating it with the sugar reward. …

If you have the time and the interest, definitely check out Daley’s article.

Here’s a link to and a citation for the latest paper about honeybees and math,

Surpassing the subitizing threshold: appetitive–aversive conditioning improves discrimination of numerosities in honeybees by Scarlett R. Howard, Aurore Avarguès-Weber, Jair E. Garcia, Andrew D. Greentree, Adrian G. Dyer. Journal of Experimental Biology 2019 222: jeb205658 doi: 10.1242/jeb.205658 Published 10 October 2019

This paper is behind a paywall.