Monthly Archives: January 2020

Of puke, CRISPR, fruit flies, and monarch butterflies

I’ve never seen an educational institution use a somewhat vulgar slang term such as ‘puke’ before. Especially not in a news release. You’ll find that elsewhere online ‘puke’ has been replaced, in the headline, with the more socially acceptable ‘vomit’.

Since I wanted to catch this historic moment amid concerns that the original version of the news release will disappear, I’m including the entire news release as i saw it on EurekAlert.com (from an October 2, 2019 University of California at Berkeley news release),

News Release 2-Oct-2019

CRISPRed fruit flies mimic monarch butterfly — and could make you puke
Scientists recreate in flies the mutations that let monarch butterfly eat toxic milkweed with impunity

University of California – Berkeley

The fruit flies in Noah Whiteman’s lab may be hazardous to your health.

Whiteman and his University of California, Berkeley, colleagues have turned perfectly palatable fruit flies — palatable, at least, to frogs and birds — into potentially poisonous prey that may cause anything that eats them to puke. In large enough quantities, the flies likely would make a human puke, too, much like the emetic effect of ipecac syrup.

That’s because the team genetically engineered the flies, using CRISPR-Cas9 gene editing, to be able to eat milkweed without dying and to sequester its toxins, just as America’s most beloved butterfly, the monarch, does to deter predators.

This is the first time anyone has recreated in a multicellular organism a set of evolutionary mutations leading to a totally new adaptation to the environment — in this case, a new diet and new way of deterring predators.

Like monarch caterpillars, the CRISPRed fruit fly maggots thrive on milkweed, which contains toxins that kill most other animals, humans included. The maggots store the toxins in their bodies and retain them through metamorphosis, after they turn into adult flies, which means the adult “monarch flies” could also make animals upchuck.

The team achieved this feat by making three CRISPR edits in a single gene: modifications identical to the genetic mutations that allow monarch butterflies to dine on milkweed and sequester its poison. These mutations in the monarch have allowed it to eat common poisonous plants other insects could not and are key to the butterfly’s thriving presence throughout North and Central America.

Flies with the triple genetic mutation proved to be 1,000 times less sensitive to milkweed toxin than the wild fruit fly, Drosophila melanogaster.

Whiteman and his colleagues will describe their experiment in the Oct. 2 [2019] issue of the journal Nature.

Monarch flies

The UC Berkeley researchers created these monarch flies to establish, beyond a shadow of a doubt, which genetic changes in the genome of monarch butterflies were necessary to allow them to eat milkweed with impunity. They found, surprisingly, that only three single-nucleotide substitutions in one gene are sufficient to give fruit flies the same toxin resistance as monarchs.

“All we did was change three sites, and we made these superflies,” said Whiteman, an associate professor of integrative biology. “But to me, the most amazing thing is that we were able to test evolutionary hypotheses in a way that has never been possible outside of cell lines. It would have been difficult to discover this without having the ability to create mutations with CRISPR.”

Whiteman’s team also showed that 20 other insect groups able to eat milkweed and related toxic plants – including moths, beetles, wasps, flies, aphids, a weevil and a true bug, most of which sport the color orange to warn away predators – independently evolved mutations in one, two or three of the same amino acid positions to overcome, to varying degrees, the toxic effects of these plant poisons.

In fact, his team reconstructed the one, two or three mutations that led to each of the four butterfly and moth lineages, each mutation conferring some resistance to the toxin. All three mutations were necessary to make the monarch butterfly the king of milkweed.
Resistance to milkweed toxin comes at a cost, however. Monarch flies are not as quick to recover from upsets, such as being shaken — a test known as “bang” sensitivity.

“This shows there is a cost to mutations, in terms of recovery of the nervous system and probably other things we don’t know about,” Whiteman said. “But the benefit of being able to escape a predator is so high … if it’s death or toxins, toxins will win, even if there is a cost.”

Plant vs. insect

Whiteman is interested in the evolutionary battle between plants and parasites and was intrigued by the evolutionary adaptations that allowed the monarch to beat the milkweed’s toxic defense. He also wanted to know whether other insects that are resistant — though all less resistant than the monarch — use similar tricks to disable the toxin.

“Since plants and animals first invaded land 400 million years ago, this coevolutionary arms race is thought to have given rise to a lot of the plant and animal diversity that we see, because most animals are insects, and most insects are herbivorous: they eat plants,” he said.

Milkweeds and a variety of other plants, including foxglove, the source of digitoxin and digoxin, contain related toxins — called cardiac glycosides — that can kill an elephant and any creature with a beating heart. Foxglove’s effect on the heart is the reason that an extract of the plant, in the genus Digitalis, has been used for centuries to treat heart conditions, and why digoxin and digitoxin are used today to treat congestive heart failure.

These plants’ bitterness alone is enough to deter most animals, but a small minority of insects, including the monarch (Danaus plexippus) and its relative, the queen butterfly (Danaus gilippus), have learned to love milkweed and use it to repel predators.

Whiteman noted that the monarch is a tropical lineage that invaded North America after the last ice age, in part enabled by the three mutations that allowed it to eat a poisonous plant other animals could not, giving it a survival edge and a natural defense against predators.

“The monarch resists the toxin the best of all the insects, and it has the biggest population size of any of them; it’s all over the world,” he said.

The new paper reveals that the mutations had to occur in the right sequence, or else the flies would never have survived the three separate mutational events.

Thwarting the sodium pump

The poisons in these plants, most of them a type of cardenolide, interfere with the sodium/potassium pump (Na+/K+-ATPase) that most of the body’s cells use to move sodium ions out and potassium ions in. The pump creates an ion imbalance that the cell uses to its favor. Nerve cells, for example, transmit signals along their elongated cell bodies, or axons, by opening sodium and potassium gates in a wave that moves down the axon, allowing ions to flow in and out to equilibrate the imbalance. After the wave passes, the sodium pump re-establishes the ionic imbalance.

Digitoxin, from foxglove, and ouabain, the main toxin in milkweed, block the pump and prevent the cell from establishing the sodium/potassium gradient. This throws the ion concentration in the cell out of whack, causing all sorts of problems. In animals with hearts, like birds and humans, heart cells begin to beat so strongly that the heart fails; the result is death by cardiac arrest.

Scientists have known for decades how these toxins interact with the sodium pump: they bind the part of the pump protein that sticks out through the cell membrane, clogging the channel. They’ve even identified two specific amino acid changes or mutations in the protein pump that monarchs and the other insects evolved to prevent the toxin from binding.

But Whiteman and his colleagues weren’t satisfied with this just so explanation: that insects coincidentally developed the same two identical mutations in the sodium pump 14 separate times, end of story. With the advent of CRISPR-Cas9 gene editing in 2012, coinvented by UC Berkeley’s Jennifer Doudna, Whiteman and colleagues Anurag Agrawal of Cornell University and Susanne Dobler of the University of Hamburg in Germany applied to the Templeton Foundation for a grant to recreate these mutations in fruit flies and to see if they could make the flies immune to the toxic effects of cardenolides.

Seven years, many failed attempts and one new grant from the National Institutes of Health later, along with the dedicated CRISPR work of GenetiVision of Houston, Texas, they finally achieved their goal. In the process, they discovered a third critical, compensatory mutation in the sodium pump that had to occur before the last and most potent resistance mutation would stick. Without this compensatory mutation, the maggots died.

Their detective work required inserting single, double and triple mutations into the fruit fly’s own sodium pump gene, in various orders, to assess which ones were necessary. Insects having only one of the two known amino acid changes in the sodium pump gene were best at resisting the plant poisons, but they also had serious side effects — nervous system problems — consistent with the fact that sodium pump mutations in humans are often associated with seizures. However, the third, compensatory mutation somehow reduces the negative effects of the other two mutations.

“One substitution that evolved confers weak resistance, but it is always present and allows for substitutions that are going to confer the most resistance,” said postdoctoral fellow Marianna Karageorgi, a geneticist and evolutionary biologist. “This substitution in the insect unlocks the resistance substitutions, reducing the neurological costs of resistance. Because this trait has evolved so many times, we have also shown that this is not random.”

The fact that one compensatory mutation is required before insects with the most resistant mutation could survive placed a constraint on how insects could evolve toxin resistance, explaining why all 21 lineages converged on the same solution, Whiteman said. In other situations, such as where the protein involved is not so critical to survival, animals might find different solutions.

“This helps answer the question, ‘Why does convergence evolve sometimes, but not other times?'” Whiteman said. “Maybe the constraints vary. That’s a simple answer, but if you think about it, these three mutations turned a Drosophila protein into a monarch one, with respect to cardenolide resistance. That’s kind of remarkable.”

###

The research was funded by the Templeton Foundation and the National Institutes of Health. Co-authors with Whiteman and Agrawal are co-first authors Marianthi Karageorgi of UC Berkeley and Simon Groen, now at New York University; Fidan Sumbul and Felix Rico of Aix-Marseille Université in France; Julianne Pelaez, Kirsten Verster, Jessica Aguilar, Susan Bernstein, Teruyuki Matsunaga and Michael Astourian of UC Berkeley; Amy Hastings of Cornell; and Susanne Dobler of Universität Hamburg in Germany.

Robert Sanders’ Oct. 2, 2019′ news release for the University of California at Berkeley (it’s also been republished as an Oct. 2, 2019 news item on ScienceDaily) has had its headline changed to ‘vomit’ but you’ll find the more vulgar word remains in two locations of the second paragraph of the revised new release.

If you have time, go to the news release on the University of California at Berkeley website just to admire the images that have been embedded in the news release. Here’s one,

Caption: A Drosophila melanogaster “monarch fly” with mutations introduced by CRISPR-Cas9 genome editing (V111, S119 and H122) to the sodium potassium pump, on a wing of a monarch butterfly (Danaus plexippus). Credit & Ccpyright: Julianne Pelaez

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

Genome editing retraces the evolution of toxin resistance in the monarch butterfly by Marianthi Karageorgi, Simon C. Groen, Fidan Sumbul, Julianne N. Pelaez, Kirsten I. Verster, Jessica M. Aguilar, Amy P. Hastings, Susan L. Bernstein, Teruyuki Matsunaga, Michael Astourian, Geno Guerra, Felix Rico, Susanne Dobler, Anurag A. Agrawal & Noah K. Whiteman. Nature (2019) DOI: https://doi.org/10.1038/s41586-019-1610-8 Published 02 October 2019

This paper is behind a paywall.

Words about a word

I’m glad they changed the headline and substituted vomit for puke. I think we need vulgar and/or taboo words to release anger or disgust or other difficult emotions. Incorporating those words into standard language deprives them of that power.

The last word: Genetivision

The company mentioned in the new release, Genetivision, is the place to go for transgenic flies. Here’s a sampling from the their Testimonials webpage,

GenetiVision‘s service has been excellent in the quality and price. The timeliness of its international service has been a big plus. We are very happy with its consistent service and the flies it generates.”
Kwang-Wook Choi, Ph.D.
Department of Biological Sciences
Korea Advanced Institute of Science and Technology


“We couldn’t be happier with GenetiVision. Great prices on both standard P and PhiC31 transgenics, quick turnaround time, and we’re still batting 1000 with transformant success. We used to do our own injections but your service makes it both faster and more cost-effective. Thanks for your service!”
Thomas Neufeld, Ph.D.
Department of Genetics, Cell Biology and Development
University of Minnesota

You can find out more here at the Genetivision website.

Humans with built-in night vision thanks to nanoparticles

In the world of video games such as the Deus Ex series eye augmentations are standard,now it seems that fantasy could become reality according to the latest American Chemical Society (ACS) meeting held in Fall 2019. From an August 27, 2019 news item on Nanowerk,

Movies featuring heroes with superpowers, such as flight, X-ray vision or extraordinary strength, are all the rage. But while these popular characters are mere flights of fancy, scientists have used nanoparticles to confer a real superpower on ordinary mice: the ability to see near-infrared light. Today, scientists report progress in making versions of these nanoparticles that could someday give built-in night vision to humans.

The researchers will present their results at the American Chemical Society (ACS) Fall 2019 National Meeting & Exposition.

“When we look at the universe, we see only visible light,” says Gang Han, Ph.D., the project’s principal investigator, who is presenting the work at the meeting. “But if we had near-infrared vision, we could see the universe in a whole new way. We might be able to do infrared astronomy with the naked eye, or have night vision without bulky equipment.”

An August 27, 2019 ACS news release, which originated the news item, explores the research about mammalian eyes (specifically mice) being presented in more depth,

The eyes of humans and other mammals can detect light between the wavelengths of 400 and 700 nanometers (nm). Near-infrared (NIR) light, on the other hand, has longer wavelengths — 750 nm to 1.4 micrometers. Thermal imaging cameras can help people see in the dark by detecting NIR radiation given off by organisms or objects, but these devices are typically bulky and inconvenient. Han and his colleagues wondered whether they could give mice NIR vision by injecting a special type of nanomaterial, called upconversion nanoparticles (UCNPs), into their eyes. These nanoparticles, which contain the rare-earth elements erbium and ytterbium, can convert low-energy photons from NIR light into higher-energy green light that mammalian eyes can see.

In work published earlier this year [2019], the researchers, who are at the University of Massachusetts Medical School, targeted UCNPs to photoreceptors in mouse eyes by attaching a protein that binds to a sugar molecule on the photoreceptor surface. Then, they injected the photoreceptor-binding UCNPs behind the retinas of the mice. To determine whether the injected mice could see and mentally process NIR light, the team conducted several physiological and behavioral tests. For example, in one test, the researchers placed the mice into a Y-shaped tank of water. One branch of the tank had a platform that the mice could climb on to escape the water. The researchers trained the mice to swim toward visible light in the shape of a triangle, which marked the escape route. A similarly lit circle marked the branch without a platform. Then, the researchers replaced the visible light with NIR light. “The mice with the particle injection could see the triangle clearly and swim to it each time, but the mice without the injection could not see or tell the difference between the two shapes,” says Han. A video of this work, posted by Han’s institution, can be viewed here.

Although the UCNPs persisted in the mice’s eyes for at least 10 weeks and did not cause any noticeable side effects, Han wants to improve the safety and sensitivity of the nanomaterials before he contemplates trying them out in humans. “The UCNPs in our published paper are inorganic, and there are some drawbacks there,” Han says. “The biocompatibility is not completely clear, and we need to improve the brightness of the nanoparticles for human use.” Now, the team is experimenting with UCNPs made up of two organic dyes, instead of rare-earth elements. “We’ve shown that we can make organic UCNPs with much improved brightness compared with the inorganic ones,” he says. These organic nanoparticles can emit either green or blue light. In addition to having improved properties, the organic dyes could also have fewer regulatory hurdles.

One of the next steps for the project might be translating the technology to man’s best friend. “If we had a super dog that could see NIR light, we could project a pattern onto a lawbreaker’s’ body from a distance, and the dog could catch them without disturbing other people,” Han says. Superhero powers aside, the technology could also have important medical applications, such as treating diseases of the eye. “We’re actually looking at how to use NIR light to release a drug from the UNCPs specifically at the photoreceptors,” Han says.

Here’s a link to and a citation for the paper mentioned in the ACS news release,

Mammalian Near-Infrared Image Vision through Injectable and Self-Powered Retinal Nanoantennae by Yuqian Ma, Jin Bao, Yuanwei Zhang, Zhanjun Li, Xiangyu Zhou. Changlin Wan, Ling Huang, Yang Zhao, Gang Han, Tian Xue. Cell Volume 177, ISSUE 2, P243-255.e15, April 04, 2019 DOI:https://doi.org/10.1016/j.cell.2019.01.038 First published online: February 28, 2019

This paper appears to be open access.

It’s going to be a while before this research makes it to human clinical trials, assuming it does. In the meantime, it seems that the plan is to continue research using dogs.

As you wait to find out how the researchers progress, you can check out my most recent mention of the Deus Ex video game series in a Sept. 1, 2016 posting about the latest entry to the series: Deus Ex: Mankind Divided.

Nanotechnology book suggestions for 2020

A January 23, 2020 news item on Nanowerk features a number of new books. Here are summaries of a couple of them from the news item (Note: Links have been removed),

The main goal of “Nanotechnology in Skin, Soft Tissue, and Bone Infections” is to deal with the role of nanobiotechnology in skin, soft tissue and bone infections since it is difficult to treat the infections due to the development of resistance in them against existing antibiotics.

The present interdisciplinary book is very useful for a diverse group of readers including nanotechnologists, medical microbiologists, dermatologists, osteologists, biotechnologists, bioengineers.

Nanotechnology in Skin, Soft-Tissue, and Bone Infections” is divided into four sections: Section I- includes role of nanotechnology in skin infections such as atopic dermatitis, and nanomaterials for combating infections caused by bacteria and fungi. Section II- incorporates how nanotechnology can be used for soft-tissue infections such as diabetic foot ulcer and other wound infections; Section III- discusses about the nanomaterials in artificial scaffolds bone engineering and bone infections caused by bacteria and fungi; and also about the toxicity issues generated by the nanomaterials in general and nanoparticles in particular.

Advanced Materials for Defense: Development, Analysis and Applications” is a collection of high quality research and review papers submitted to the 1st World Conference on Advanced Materials for Defense (AUXDEFENSE 2018).

A wide range of topics related to the defense area such as ballistic protection, impact and energy absorption, composite materials, smart materials and structures, nanomaterials and nano structures, CBRN protection, thermoregulation, camouflage, auxetic materials, and monitoring systems is covered.

Written by the leading experts in these subjects, this work discusses both technological advances in terms of materials as well as product designing, analysis as well as case studies.

This volume will prove to be a valuable resource for researchers and scientists from different engineering disciplines such as materials science, chemical engineering, biological sciences, textile engineering, mechanical engineering, environmental science, and nanotechnology.

Nanoengineering is a branch of engineering that exploits the unique properties of nanomaterials—their size and quantum effects—and the interaction between these materials, in order to design and manufacture novel structures and devices that possess entirely new functionality and capabilities, which are not obtainable by macroscale engineering.

While the term nanoengineering is often used synonymously with the general term nanotechnology, the former technically focuses more closely on the engineering aspects of the field, as opposed to the broader science and general technology aspects that are encompassed by the latter.

Nanoengineering: The Skills and Tools Making Technology Invisible” puts a spotlight on some of the scientists who are pushing the boundaries of technology and it gives examples of their work and how they are advancing knowledge one little step at a time.

This book is a collection of essays about researchers involved in nanoengineering and many other facets of nanotechnologies. This research involves truly multidisciplinary and international efforts, covering a wide range of scientific disciplines such as medicine, materials sciences, chemistry, toxicology, biology and biotechnology, physics and electronics.

The book showcases 176 very specific research projects and you will meet the scientists who develop the theories, conduct the experiments, and build the new materials and devices that will make nanoengineering a core technology platform for many future products and applications.

On January 28, 2020, Azonano featured a book review for “Nano Comes to Life: How Nanotechnology is Transforming Medicine and the Future of Biology.” The review by Rebecca Megson-Smith, marketing lead, was originally published on the NuNano company blog

Covering sciences ‘greatest hits’ since we have been able to look at the world on the nanoscale, as well as where it is taking our understanding of life, Nano Comes to Life: How Nanotechnology is Transforming Medicine and the Future of Biology is an inspiring and joyful read.

As author Sonia Contera writes, biology is an area of intense interest and study. With the advent of nanotechnology, a more diverse range of scientists from across the disciplines are now coming together to solve some of the biggest issues of our time.

The ability to visualise, interact with, manipulate and create matter at the nanometer scale – the level of molecules, proteins and DNA – combined with the physicists quantitative and mathematical approach is revolutionising our understanding of the complexity which underpins life.

I particularly enjoyed the section that discussed the history of scanning tools. Here Contera highlights how profoundly the development of the STM [scanning tunneling microscope] transformed human interaction with matter.

Not only did it image at the atomic level with ‘unprecedented accuracy using a relatively simple, cheap tool’, but the STM was able to pick up and move the atoms around one by one. And what it couldn’t do effectively – work within the biological environments – was and is achievable through the introduction of the AFM [atomic force microscope].

She [Contera] writes:

“Physics urges us to consider life as a whole emergent from the greater whole – emanating from the same rules that govern the entire cosmos.”

I leave you with another bold declaration from Sonia about the good that the merging of the sciences has offered and, on behalf of everyone at NuNano, would like to wish you all a very Merry Christmas and Happy New Year – see you in 2020!

“As physics, engineering, computer science and materials science merge with biology, they are actually helping to reconnect science and technology with the deep questions that humans have asked themselves from the beginning of civilization: What is life? What does it mean to be human when we can manipulate and even exploit our own biology?”

Sonia Contera is professor of biological physics in the Department of Physics at the University of Oxford. She is a leading pioneer in the field of nanotechnology.

Megson-Smith certainly seems enthused about the book and she reminded me of how interested I was in STMs and AFMs when I first started investigating and writing about nanotechnology. Given the review but not having seen the book myself, it seems this might be a good introduction.

My introductory book was the 2009 Soft Machines: Nanotechnology and Life by Richard Jones, a professor of physics and astronomy at the University of Sheffield. I have great affection for the book and, if memory serves, it hasn’t really aged. One more thing, Jones can be very funny. It’s not many people who can successfully combine humour and nanotechnology.

You can find Megson-Smith’s original posting here.

Harvard professor and leader in nanoscale electronics charged with making false statements about Chinese funding

I may be mistaken but the implication seems to be that Charles M. Lieber’s lies (he was charged today, January 28, 2020 ) are the ‘tip of the iceberg’ of a very large problem. Ellen Barry’s January 28, 2020 article for the New York Times outlines at least part of what the US government is doing to discover and ultimately discourage the theft of biomedical research from US laboratories.

Dr. Lieber, a leader in the field of nanoscale electronics, was one of three Boston-area scientists accused on Tuesday [January 28, 2020] of working on behalf of China. His case involves work with the Thousand Talents Program, a state-run program that seeks to draw talent educated in other countries.

American officials are investigating hundreds of cases of suspected theft of intellectual property by visiting scientists, nearly all of them Chinese nationals or of Chinese descent. Some are accused of obtaining patents in China based on work that is funded by the United States government, and others of setting up laboratories in China that secretly duplicated American research.

Dr. Lieber, who was arrested on Tuesday [January 28, 2020], stands out among the accused scientists, because he is neither Chinese nor of Chinese descent. …

Lieber is the Chair of Harvard’s Department of Chemistry and Chemical Biology and much more, according to his Wikipedia entry (Note: Links have been removed),

Charles M. Lieber (born 1959) is an American chemist and pioneer in the field of nanoscience and nanotechnology. In 2011, Lieber was recognized by Thomson Reuters as the leading chemist in the world for the decade 2000-2010 based on the impact of his scientific publications.[1] Lieber has published over 400 papers in peer-reviewed scientific journals and has edited and contributed to many books on nanoscience.[2] He is the principal inventor on over fifty issued US patents and applications, and founded the nanotechnology company Nanosys in 2001 and Vista Therapeutics in 2007.[3] He is known for his contributions to the synthesis, assembly and characterization of nanoscale materials and nanodevices, the application of nanoelectronic devices in biology, and as a mentor to numerous leaders in nanoscience.[4] Thompson Reuters predicted Lieber to be a recipient of the 2008 Nobel Prize in Chemistry [to date, January 28, 2020, Lieber has not received a Nobel prize].

Should you search Charles Lieber or Charles M. Lieber on this blog’s search engine, you will find a number of postings about his and his students’ work dating from 2012 to as recently as November 15, 2019.

Here’s another example from Barry’s January 28, 2020 article for the New York Times which illustrates just how shocking this is (Note: Links have been removed),

In 2017 he was named a University Professor, Harvard’s highest faculty rank, one of only 26 professors to hold that status. The same year, he earned the National Institutes of Health Director’s Pioneer Award for inventing syringe-injectable mesh electronics that can integrate with the brain.

Harvard’s president at the time, Drew G. Faust, called him “an extraordinary scientist whose work has transformed nanoscience and nanotechnology and has led to a remarkable range of valuable applications that improve the quality of people’s lives.”

Here’s a bit more about the Chinese program that Lieber is affiliated with,

Launched in 2008, its [China] Thousand Talents Program is an effort to recruit Chinese and foreign academics and entrepreneurs. According to a report in the China Daily, new recruits receive 1 million yuan, or about $146,000, from the central government, and a pledge of 10 million yuan for their ongoing research from the Chinese Academy of Sciences.

The recruitment flows both ways. Researchers of Chinese descent make up nearly half of the work force in American research laboratories, in part because American-born scientists are drawn to the private sector and less interested in academic careers.

I encourage you to read Barry’s entire article. It is jaw-dropping and, where Lieber is concerned, sad. It’s beginning to look like US universities are corrupt. The ‘Jeffrey Epstein (a wealthy and convicted sexual predator and more) connection’ to the Massachusetts Institute of Technology, which led to the resignation of a prominent faculty member (Sept. 19, 2019 article by Anna North for Vox.com), and the Fall 2019 cheating scandal (gaining admission to big name educational institutions by paying someone other than the student to take exams, among many other schemes) suggest a reckoning might be in order.

ETA January 28, 2020 at 1645 hours: I found a January 28, 2020 article by Antonio Regalado for the MIT Technology Review which provides a few more details about Lieber’s situation,

Big money: According to the charging document, Lieber, starting in 2011,  agreed to help set up a research lab at the Wuhan University of Technology and “make strategic visionary and creative research proposals” so that China could do cutting-edge science.

He was well paid for it. Lieber earned a salary when he visited China worth up to $50,000 per month, as well as $150,000 a year in expenses in addition to research funds. According to the complaint, he got paid by way of a Chinese bank account but also was known to send emails asking for cash instead.

Harvard eventually wised up to the existence of a Wuhan lab using its name and logo, but when administrators confronted Lieber, he lied and said he didn’t know about a formal joint program, according to the government complaint.

I imagine the money paid by the Chinese government is in addition to Lieber’s Harvard salary (no doubt a substantial one especially since he’s chair of his department and one of a select number of Harvard’s University Professors) and in addition to any other deals he might have on the side.

Entanglement at 50 km

An August 29, 2019 news item on phys.org broke the news about breaking a record for transferring quantum entanglement between matter and light ,

The quantum internet promises absolutely tap-proof communication and powerful distributed sensor networks for new science and technology. However, because quantum information cannot be copied, it is not possible to send this information over a classical network. Quantum information must be transmitted by quantum particles, and special interfaces are required for this. The Innsbruck-based experimental physicist Ben Lanyon, who was awarded the Austrian START Prize in 2015 for his research, is investigating these important intersections of a future quantum Internet.

Now his team at the Department of Experimental Physics at the University of Innsbruck and at the Institute of Quantum Optics and Quantum Information of the Austrian Academy of Sciences has achieved a record for the transfer of quantum entanglement between matter and light. For the first time, a distance of 50 kilometers was covered using fiber optic cables. “This is two orders of magnitude further than was previously possible and is a practical distance to start building inter-city quantum networks,” says Ben Lanyon.

An August 29, 2019 University of Innsbruck press release (also on EurekAlert), which originated the news item,

Converted photon for transmission

Lanyon’s team started the experiment with a calcium atom trapped in an ion trap. Using laser beams, the researchers write a quantum state onto the ion and simultaneously excite it to emit a photon in which quantum information is stored. As a result, the quantum states of the atom and the light particle are entangled. But the challenge is to transmit the photon over fiber optic cables. “The photon emitted by the calcium ion has a wavelength of 854 nanometers and is quickly absorbed by the optical fiber”, says Ben Lanyon. His team therefore initially sends the light particle through a nonlinear crystal illuminated by a strong laser. Thereby the photon wavelength is converted to the optimal value for long-distance travel: the current telecommunications standard wavelength of 1550 nanometers. The researchers from Innsbruck then send this photon through a 50-kilometer-long optical fiber line. Their measurements show that atom and light particle are still entangled even after the wavelength conversion and this long journey.

Even greater distances in sight

As a next step, Lanyon and his team show that their methods would enable entanglement to be generated between ions 100 kilometers apart and more. Two nodes send each an entangled photon over a distance of 50 kilometers to an intersection where the light particles are measured in such a way that they lose their entanglement with the ions, which in turn would entangle them. With 100-kilometer node spacing now a possibility, one could therefore envisage building the world’s first intercity light-matter quantum network in the coming years: only a handful of trapped ion-systems would be required on the way to establish a quantum internet between Innsbruck and Vienna, for example.

Lanyon’s team is part of the Quantum Internet Alliance, an international project within the Quantum Flagship framework of the European Union. The current results have been published in the Nature journal Quantum Information. Financially supported was the research among others by the Austrian Science Fund FWF and the European Union.

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

Light-matter entanglement over 50 km of optical fibre by V. Krutyanskiy, M. Meraner, J. Schupp, V. Krcmarsky, H. Hainzer & B. P. Lanyon. npj Quantum Information volume 5, Article number: 72 (2019) DOI: https://doi.org/10.1038/s41534-019-0186-3 Published: 27 August 2019

This paper is open access.

January 30, 2020 in Ottawa: When your city is smarter than you

Should you be in Ottawa, Canada on January 30, 2020 you might want to check out the Curiosity on Stage event: ‘When your city is smarter than you’ at the Canada Science and Technology Museum (from the Ingenium event page),

Curiosity on Stage: Evening Edition – When your city is smarter than you

Location Event Hall

When January 30, 2020

Times 7 p.m. – 8:30 p.m. (a reception will be held before the event, from 6:30 p.m. – 7 p.m.)

Fee Description $10 for non-members, $7 for museum members and students.

Registration required.

Language Comments Please note that this presentation will be in English, with simultaneous translation into French, and a bilingual Q & A.

Please note that the topics under discussion are intended for mature audiences. Recommended for participants ages 15 and up.

In June 2019, Google’s Sidewalk Labs released a long-awaited development proposal for a Toronto waterfront community, and in doing so created the largest ever smart city experiment in the world. For some, Sidewalk Labs’ proposal promises the key elements of a sustainable and inclusive city. For others, the proposal illustrates the dangers of letting a private corporation invade further into our private lives.

As part of our “Living in the Machine Age” theme, join a lively discussion exploring the future of cities in an increasingly algorithmic world. The session will end with a panel discussion and question-and-answer period.

Join the conversation! Share your thoughts using the hashtag #CuriosityOnStage.

Please note that parking fees will be in effect.

If you require translation, please consider helping the environment by bringing your own Internet-compatible device (phone or tablet) and headphones.

Here’s more detail about the agenda and the speakers (from the Ingenium event page),

Agenda:

6:30 p.m. – 7 p.m.: Light refreshments and networking opportunities

7 p.m. – 8:30 p.m.: Presentations and panel discussion

8:30 p.m. – 9 p.m.: Light refreshments and networking opportunities

Our speakers:

Dr Tracey P. Lauriault – Assistant Professor, Carleton University

Marc René de Cotret – Director, Service Transformation of City of Ottawa

Biographies

Dr Tracey P. Lauriault – Assistant Professor, Carleton University

Dr Tracey P. Lauriault, Assistant Professor, Critical Media and Big Data, School of Journalism and Communication, and Cross Appointed to the MA in Digital Humanities and Faculty of the Institute for Data Science, Carleton University.

Lauriault’s work on open data, big data, open smart cities, is international, transdisciplinary and multi-sectoral. She is one of the founders of critical data studies and of open data in Canada and founded Open Smart Cities with OpenNorth a data and technology governance approach shaping how Canadian cities roll out their ‘smart’ programs. Her scholarship is critical and engaged, and as a data and technological citizen, she works with the makers, governors and stakeholders of these data, processes and infrastructures, not only to better understand them but also to ensure that these do not cause harm and more so that they are governed in an ethical, accountable and transparent way so as to balance economic development, social progress and environmental responsibility.

Marc René de Cotret – Director, Service Transformation of City of Ottawa

Marc René de Cotret joined the City of Ottawa’s Innovative Client Services Department as the Director of Service Transformation in April 2017.

He leads the Service Transformation team, which is responsible for delivering the City’s strategic planning process, smart city strategy, digital and innovation initiatives, open data program, and organizational effectiveness efforts to cultivate a culture of innovation and client-centric service delivery.

Prior to joining the City, Marc was an Associate Partner with the Digital Operations practice of IBM’s Global Business Services. He has extensive consulting experience in strategy, business operations, and transformation. He has worked for large-scale clients in numerous sectors including all levels of government, public safety, health care, construction and engineering, defense, pulp & paper, industrial shipbuilding, nuclear regulatory, and taxation.

Marc has a master’s degree in Business Administration from the University of Ottawa.

Go here to register.

Second order memristor

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

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

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

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

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

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

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

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

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

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

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

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

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

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

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

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

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

MIPT has provided this image illustrating the research,

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

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

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

This paper is behind a paywall.

Control your electronics devices with your clothing while protecting yourself from bacteria

Purdue University researchers have developed a new fabric innovation that allows the wearer to control electronic devices through the clothing. Courtesy: Purdue University

I like the image but do they really want someone pressing a cufflink? Anyway, being able to turn on your house lights and music system with your clothing would certainly be convenient. From an August 8, 2019 Purdue University (Indiana, US) news release (also on EurekAlert) by Chris Adam,

A new addition to your wardrobe may soon help you turn on the lights and music – while also keeping you fresh, dry, fashionable, clean and safe from the latest virus that’s going around.

Purdue University researchers have developed a new fabric innovation that allows wearers to control electronic devices through clothing.

“It is the first time there is a technique capable to transform any existing cloth item or textile into a self-powered e-textile containing sensors, music players or simple illumination displays using simple embroidery without the need for expensive fabrication processes requiring complex steps or expensive equipment,” said Ramses Martinez, an assistant professor in the School of Industrial Engineering and in the Weldon School of Biomedical Engineering in Purdue’s College of Engineering.

The technology is featured in the July 25 [2019] edition of Advanced Functional Materials.

“For the first time, it is possible to fabricate textiles that can protect you from rain, stains, and bacteria while they harvest the energy of the user to power textile-based electronics,” Martinez said. “These self-powered e-textiles also constitute an important advancement in the development of wearable machine-human interfaces, which now can be washed many times in a conventional washing machine without apparent degradation.

Martinez said the Purdue waterproof, breathable and antibacterial self-powered clothing is based on omniphobic triboelectric nanogeneragtors (RF-TENGs) – which use simple embroidery and fluorinated molecules to embed small electronic components and turn a piece of clothing into a mechanism for powering devices. The Purdue team says the RF-TENG technology is like having a wearable remote control that also keeps odors, rain, stains and bacteria away from the user.

“While fashion has evolved significantly during the last centuries and has easily adopted recently developed high-performance materials, there are very few examples of clothes on the market that interact with the user,” Martinez said. “Having an interface with a machine that we are constantly wearing sounds like the most convenient approach for a seamless communication with machines and the Internet of Things.”

The technology is being patented through the Purdue Research Foundation Office of Technology Commercialization. The researchers are looking for partners to test and commercialize their technology.

Their work aligns with Purdue’s Giant Leaps celebration of the university’s global advancements in artificial intelligence and health as part of Purdue’s 150th anniversary. It is one of the four themes of the yearlong celebration’s Ideas Festival, designed to showcase Purdue as an intellectual center solving real-world issues.

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

Waterproof, Breathable, and Antibacterial Self‐Powered e‐Textiles Based on Omniphobic Triboelectric Nanogenerators by Marina Sala de Medeiros, Daniela Chanci, Carolina Moreno, Debkalpa Goswami, Ramses V. Martinez. Advanced Functional Materials DOI: https://doi.org/10.1002/adfm.201904350 First published online: 25 July 2019

This paper is behind a paywall.

Space debris, water, and DIY biology, science events in Canada (Jan. 22 – 23, 2020)

There is a lot happening in the next day or two. I have two Vancouver (Canada) science events and an online event, which can be attended from anywhere.

Space debris on January 23, 2020 in Vancouver

I was surprised to learn about space debris (it was described as a floating junkyard in space) in 1992. It seems things have not gotten better. Here’s more from the Cosmic Nights: Space Debris event page on the H.R. MacMillan Space Centre website,

Cosmic Nights: Space Debris

….

There are tens of thousands of pieces of man-made debris, or “space junk,” orbiting the Earth that threaten satellites and other spacecraft. With the increase of space exploration and no debris removal processes in place that number is sure to increase.

Learn more about the impact space debris will have on current and future missions, space law, and the impact human activity, both scientific, and commercial are having on space as we discuss what it will take to make space exploration more sustainable. Physics professors Dr. Aaron Rosengren, and Dr. Aaron Boley will be joining us to share their expertise on the subject.

Tickets available for 7:30pm or 9:00pm planetarium star theatre shows.
________________

7:30 ticket holder schedule:
6:30 – check-in
7:00 – “Pooping in Space” (GroundStation Canada Theatre)
7:30 – 8:30 “Go Boldly and Sustainably” show (Planetarium Star Theatre)
9:00 – 9:30 “Space Debris” lecture

9:00 ticket holder schedule:
6:30 – check-in
7:00 – 9:00 (runs every 30 mins) “Pooping in Space” show (GroundStation Canada Theatre)
8:00 – 8:30 “Space Debris” lecture
9:00 – 10:00 “Go Boldly and Sustainably” show (Planetarium Star Theatre)
The bar will be open from 6:30 – 10:00pm in the Cosmic Courtyard.

Only planetarium shows are ticketed, all other activities are optional.

7:00pm, 7:30pm, 8:00pm, 8:30pm – “Pooping in Space” – GroundStation Canada Theatre
The ultimate waste! What happens when you have to “GO” in space? In this live show you’ll see how astronauts handle this on the ISS, look at some new innovations space suit design for future missions, and we’ll have some fun astronaut trivia.

7:30pm and 9:00pm – “Go Boldly and Sustainably” – Planetarium Star Theatre
As humans venture into a solar system, where no one can own anything, it is becoming increasingly important to create policies to control for waste and promote sustainability. But who will enact these policies? Will it be our governments or private companies? Our astronomer Rachel Wang, and special guest Dr. Aaron Boley will explore these concepts under the dome in the Planetarium Star Theatre. For the 7:30 show SFU’s Paul Meyer will be making an appearance to talk about the key aspects of space security diplomacy and how it relates to the space debris challenge.

Dr. Aaron Boley is an Assistant Professor in the Physics and Astronomy department at UBC whose research program uses theory and observations to explore a wide range of processes in the formation of planets, from the birth of planet-forming discs to the long-term evolution of planetary systems.

Paul Meyer is Fellow in International Security and Adjunct Professor of International Studies at Simon Fraser University and a founding member of the Outer Space Institute. Prior to his assuming his current positions in 2011, Mr. Meyer had a 35-year career with the Canadian Foreign Service, including serving as Canada’s Ambassador to the United Nations and to the Conference on Disarmament in Geneva (2003-2007). He teaches a course on diplomacy at SFU’s School for International Studies and writes on issues of nuclear non-proliferation and disarmament, outer space security and international cyber security.

8:00pm and 9:00pm – “Space Junk: Our Quest to Conquer the Space Environment Problem” lecture by Dr. Aaron Rosengren

At the end of 2019, after nearly two decades, the U.S. government issued updated orbital debris mitigation guidelines, but the revision fell short of the sweeping changes many in the space debris research community expected. The updated guidelines sets new quantitative limits on events that can create debris and updates the classes of orbits to be used for the retirement of satellites, even allowing for the new exotic idea of passive disposal through gravitational resonances (similar phenomena have left their mark on the asteroid belt between Mars and Jupiter). The revised guidelines, however, do not make major changes, and leave intact the 25-year time frame for end-of-life disposal of low-Earth orbit satellites, a period many now believe to be far too long with the ever increasing orbital traffic in near-Earth space. In this talk, I will discuss various approaches to cleaning up or containing space junk, such as a recent exciting activity in Australia to use laser photo pressure to nudge inactive debris to safe orbits.

Dr. Aaron J. Rosengren is an Assistant Professor in the College of Engineering at the University of Arizona and Member of the Interdisciplinary Graduate Program in Applied Mathematics. Prior to joining UA in 2017, he spent one year at the Aristotle University of Thessaloniki in Greece working in the Department of Physics, as part of the European Union H2020 Project ReDSHIFT. He has also served as a member of the EU Asteroid and Space Debris Network, Stardust, working for two years at the Institute of Applied Physics Nello Carrara of the Italian National Research Council. His research interests include space situational awareness, orbital debris, celestial mechanics, and planetary science. Aaron is currently part of the Space Situational Awareness (SSA)-Arizona initiative at the University of Arizona, a member of the Outer Space Institute (OSI) for the sustainable development of Space at the University of British Columbia, and a research affiliate of the Center for Orbital Debris Education and Research (CODER) at the University of Maryland.

*Choose between either the 7:30pm or 9:00pm planetarium show when purchasing your ticket.*

This is a 19+ event. All attendees will be required to provide photo ID upon entry.

Date and Time

Thu, 23 January 2020
6:30 PM – 10:00 PM PST

Location

H.R. MacMillan Space Centre
1100 Chestnut Street
Vancouver, BC V6J 3J9

Cosmic Nights is the name for a series of talks about space and astronomy and an opportunity to socialize with your choice of beer or wine for purchase.

Canada-wide 2nd Canadian DIY Biology Summit (live audio and webcast)

This is a January 22, 2020 event accessible Canada-wide. For anyone on Pacific Time, it does mean being ready to check-in at 5 am. The first DIY Biology (‘do-it-yourself’ biology) Summit was held in 2016.

Here’s more about the event from its Open Science Network events page on Meetup,

Organizers of Community Biolabs across Canada are converging on Ottawa this Wednesday for the second Canadian DIY Biology Summit organized by the Public Health Agency of Canada (PHAC). OSN [Open Science Network] President & Co-Founder, Scott Pownall, has been invited to talk about the Future of DIY/Community Biology in Canada.

The agenda was just released. Times are East Standard Time.
https://www.opensciencenet.org/wp-content/uploads/2020/01/2020-2nd-Canadian-DYI-Biology-Summit-Agenda.pdf

You can join in remotely via WebEx or audio conferencing.

WebEx Link: https://gts-ee.webex.com/webappng/sites/gts-ee/meeting/info/1144bc57660846349f15cf6e80a6a35f

A few points of clarification: DIYbio YVR has been renamed Open Science Network on Meetup and, should you wish to attend the summit virtually, there is information about passwords and codes on the agenda, which presumably will help you to get access.

Nerd Nite v. 49: Waterslides, Oil Tankers, and Predator-Prey Relationships on January 22, 2020 in Vancouver

Here’s more about Nerd Nite Vancouver v.49 from its event posting,

When you were young, did you spend your summers zooming down waterslides? We remember days where our calves ached from climbing stairs, and sore bums from well… you know. And, if you were like us, you also stared at those slides and thought “How are these things made? And, is it going to disassemble while I’m on it?”. Today, we spend more of our summer days staring out at the oil tankers lining the shore, or watching seagulls dive down to retrieve waste left behind by tourists on Granville Island, but we maintain that curiousity about the things around us! So, splash into a New Year with us to learn about all three: waterslides, oil tankers, and predator-prey relationships.

Hosted by: Kaylee Byers and Michael Unger

Where: The Fox Cabaret

When: Wednesday January 22nd; Doors @ 7, show starts @ 7:30

Tickets: Eventbrite

Poster by: Armin Mortazavi

Music by: DJ Burger

1. Ecology

Zachary Sherker 

Zachary is completing an MSc at UBC investigating freshwater and estuarine predation on juvenile salmon during their out-migration from natal rivers and works as a part-time contract biologist in the lower mainland. Prior to coming out west, Zach completed an interdisciplinary BSc in Aquatic Resources and Biology at St. F.X. University in Antigonish, N.S. During his undergraduate degree, Zach ran field and lab experiments to explore predator-induced phenotypic plasticity in intertidal blue mussels exposed to the waterborne cues of a drilling predator snail. He also conducted biological surveys on lobster fishing boats and worked as a fisheries observer for the offshore commercial snow crab fleet.

2. Waterslides

Shane Jensen

Shane is a professional mechanical engineer whose career transitioned from submarine designer to waterslide tester. He is currently a product manager for waterslides at WhiteWater West.

3. Oil Tankers 101

Kayla Glynn 

Kayla is an ocean enthusiast. She earned her Masters in Marine Management at Dalhousie University, studying compensation for environmental damage caused by ship-source oil spills. Passionate about sharing her knowledge of the ocean with others, Kayla’s shifted her focus to the realm of science communication to help more people foster a deeper relationship with science and the ocean. Kayla now works as a producer at The Story Collider, a non-profit dedicated to sharing true, personal stories about science, where she hosts live storytelling events and leads workshops on behalf of the organization. Follow her at @kaylamayglynn and catch her live on the Story Collider stage on February 11th, 2020!

There you have it.

Gold glue?

If you’re hoping for gold flecks in your glue, this is not going to satisfy you, given that it’s all at the nanoscale. An August 7, 2019 news item on Nanowerk briefly describes this gold glue (Note: A link has been removed),

It has long been known that gold can be used to do things that philosophers have never even dreamed of. The Institute of Nuclear Physics of the Polish Academy of Sciences in Cracow has confirmed the existence of ‘gold glue’: bonds involving gold atoms, capable of permanently bonding protein rings. Skilfully used by an international team of scientists, the bonds have made it possible to construct molecular nanocages with a structure so far unparalleled in nature or even in mathematics (Nature, “An ultra-stable gold-coordinated protein cage displaying reversible assembly”).

Caption: The ‘impossible’ sphere, i.e. a molecular nanocage of 24 protein rings, each of which has an 11-sided structure. The rings are connected by bonds with the participation of gold atoms, here marked in yellow. Depending on their position in the structure, not all gold atoms have to be used to attach adjacent proteins (an unused gold atom is marked in red). Credit: Source: UJ, IFJ PAN

An August 6, 2019 Polish Academy of Sciences press release (also on EurekAlert but published August 7, 2019), which originated the news item, expands on the theme,

The world of science has been interested in molecular cages for years. Not without reason. Chemical molecules, including those that would under normal conditions enter into chemical reactions, can be enclosed within their empty interiors. The particles of the enclosed compound, separated by the walls of the cage from the environment, have nothing to bond with. These cages can be therefore be used, for example, to transport drugs safely into a cancer cell, only releasing the drug when they are inside it.

Molecular cages are polyhedra made up of smaller ‘bricks’, usually protein molecules. The bricks can’t be of any shape. For example, if we wanted to build a molecular polyhedron using only objects with the outline of an equilateral triangle, geometry would limit us to only three solid figures: a tetrahedron, an octahedron or an icosahedron. So far, there have been no other structural possibilities.

“Fortunately, Platonic idealism is not a dogma of the physical world. If you accept certain inaccuracies in the solid figure being constructed, you can create structures with shapes that are not found in nature, what’s more, with very interesting properties,” says Dr. Tomasz Wrobel from the Cracow Institute of Nuclear Physics of the Polish Academy of Sciences (IFJ PAN).

Dr. Wrobel is one of the members of an international team of researchers who have recently carried out the ‘impossible’: they built a cage similar in shape to a sphere out of eleven-walled proteins. The main authors of this spectacular success are scientists from the group of Prof. Jonathan Heddle from the Malopolska Biotechnology Centre of the Jagiellonian University in Cracow and the Japanese RIKEN Institute in Wako. The work described in Nature magazine took place with the participation of researchers from universities in Osaka and Tsukuba (Japan), Durham (Great Britain), Waterloo (Canada) and other research centres.

Each of the walls of the new nanocages was formed by a protein ring from which eleven cysteine molecules stuck out at regular intervals. It was to the sulphur atom found in each cysteine molecule that the ‘glue’, i.e. the gold atom, was planned to be attached. In the appropriate conditions, it could bind with one more sulphur atom, in the cysteine of a next ring. In this way a permanent chemical bond would be formed between the two rings. But would the gold atom under these conditions really be able to form a bond between the rings?

“In the Spectroscopic Imaging Laboratory of IFJ PAS we used Raman spectroscopy and X-ray photoelectron spectroscopy to show that in the samples provided to us with the test nanocages, the gold really did form bonds with sulphur atoms in cysteines. In other words, in a difficult, direct measurement, we proved that gold ‘glue’ for bonding protein rings in cages really does exist,” explains Dr. Wrobel.

Each gold atom can be treated as a stand-alone clip that makes it possible to attach another ring. The road to the ‘impossible’ begins when we realize that we don’t always have to use all of the clips! So, although all the rings of the new nanocages are physically the same, depending on their place in the structure they connect with their neighbours with a different number of gold atoms, and thus function as polygons with different numbers of vertices. 24 nanocage walls presented by the researchers were held together by 120 gold atoms. The outer diameter of the cages was 22 nanometres and the inner diameter was 16 nm.

Using gold atoms as a binder for nanocages is also important due to its possible applications. In earlier molecular structures, proteins were glued together using many weak chemical bonds. The complexity of the bonds and their similarity to the bonds responsible for the existence of the protein rings themselves did not allow for precise control over the decomposition of the cages. This is not the case in the new structures. On the one hand, gold-bonded nanocages are chemically and thermally stable (for example, they withstand hours of boiling in water). On the other hand, however, gold bonds are sensitive to an increase in acidity. By its increase, the nanocage can be decomposed in a controlled way and the contents can be released into the environment. Since the acidity within cells is greater than outside them, gold-bonded nanocages are ideal for biomedical applications.

The ‘impossible’ nanocage is the presentation of a qualitatively new approach to the construction of molecular cages, with gold atoms in the role of loose clips. The demonstrated flexibility of the gold bonds will make it possible in the future to create nanocages with sizes and features precisely tailored to specific needs.

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

An ultra-stable gold-coordinated protein cage displaying reversible assembly by Ali D. Malay, Naoyuki Miyazaki, Artur Biela, Soumyananda Chakraborti, Karolina Majsterkiewicz, Izabela Stupka, Craig S. Kaplan, Agnieszka Kowalczyk, Bernard M. A. G. Piette, Georg K. A. Hochberg, Di Wu, Tomasz P. Wrobel, Adam Fineberg, Manish S. Kushwah, Mitja Kelemen, Primož Vavpetič, Primož Pelicon, Philipp Kukura, Justin L. P. Benesch, Kenji Iwasaki & Jonathan G. Heddle Nature volume 569, pages438–442 (2019) Issue Date: 16 May 2019 DOI: https://doi.org/10.1038/s41586-019-1185-4 Published online: 08 May 2019

This paper is behind a paywall.