Tag Archives: University of Oxford

Spider webs inspire liquid wire

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Courtesy University of Oxford

Courtesy University of Oxford

Usually, when science talk runs to spider webs the focus is on strength but this research from the UK and France is all about resilience. From a May 16, 2016 news item on phys.org,

Why doesn’t a spider’s web sag in the wind or catapult flies back out like a trampoline? The answer, according to new research by an international team of scientists, lies in the physics behind a ‘hybrid’ material produced by spiders for their webs.

Pulling on a sticky thread in a garden spider’s orb web and letting it snap back reveals that the thread never sags but always stays taut—even when stretched to many times its original length. This is because any loose thread is immediately spooled inside the tiny droplets of watery glue that coat and surround the core gossamer fibres of the web’s capture spiral.

This phenomenon is described in the journal PNAS by scientists from the University of Oxford, UK and the Université Pierre et Marie Curie, Paris, France.

The researchers studied the details of this ‘liquid wire’ technique in spiders’ webs and used it to create composite fibres in the laboratory which, just like the spider’s capture silk, extend like a solid and compress like a liquid. These novel insights may lead to new bio-inspired technology.

A May 16, 2016 University of Oxford press release (also on EurekAlert), which originated the news item, provides more detail,

Professor Fritz Vollrath of the Oxford Silk Group in the Department of Zoology at Oxford University said: ‘The thousands of tiny droplets of glue that cover the capture spiral of the spider’s orb web do much more than make the silk sticky and catch the fly. Surprisingly, each drop packs enough punch in its watery skins to reel in loose bits of thread. And this winching behaviour is used to excellent effect to keep the threads tight at all times, as we can all observe and test in the webs in our gardens.’

The novel properties observed and analysed by the scientists rely on a subtle balance between fibre elasticity and droplet surface tension. Importantly, the team was also able to recreate this technique in the laboratory using oil droplets on a plastic filament. And this artificial system behaved just like the spider’s natural winch silk, with spools of filament reeling and unreeling inside the oil droplets as the thread extended and contracted.

Dr Hervé Elettro, the first author and a doctoral researcher at Institut Jean Le Rond D’Alembert, Université Pierre et Marie Curie, Paris, said: ‘Spider silk has been known to be an extraordinary material for around 40 years, but it continues to amaze us. While the web is simply a high-tech trap from the spider’s point of view, its properties have a huge amount to offer the worlds of materials, engineering and medicine.

‘Our bio-inspired hybrid threads could be manufactured from virtually any components. These new insights could lead to a wide range of applications, such as microfabrication of complex structures, reversible micro-motors, or self-tensioned stretchable systems.’

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

In-drop capillary spooling of spider capture thread inspires hybrid fibers with mixed solid–liquid mechanical properties by Hervé Elettro, Sébastien Neukirch, Fritz Vollrath, and Arnaud Antkowiak. PNAS doi: 10.1073/pnas.1602451113

This paper appears to be open access.

3D print the city of Palmyra (Syria)?

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Designated a World Heritage Site by UNESCO (United Nations Educational, Scientific and Cultural Organization), Palmyra dates back to Second Century BCE (before the common era) as UNESCO’s Site of Palmyra webpage indicates,

An oasis in the Syrian desert, north-east of Damascus, Palmyra contains the monumental ruins of a great city that was one of the most important cultural centres of the ancient world. From the 1st to the 2nd century, the art and architecture of Palmyra, standing at the crossroads of several civilizations, married Graeco-Roman techniques with local traditions and Persian influences.

First mentioned in the archives of Mari in the 2nd millennium BC, Palmyra was an established caravan oasis when it came under Roman control in the mid-first century AD as part of the Roman province of Syria.  It grew steadily in importance as a city on the trade route linking Persia, India and China with the Roman Empire, marking the crossroads of several civilisations in the ancient world. A grand, colonnaded street of 1100 metres’ length forms the monumental axis of the city, which together with secondary colonnaded cross streets links the major public monuments including the Temple of Ba’al, Diocletian’s Camp, the Agora, Theatre, other temples and urban quarters. Architectural ornament including unique examples of funerary sculpture unites the forms of Greco-roman art with indigenous elements and Persian influences in a strongly original style. Outside the city’s walls are remains of a Roman aqueduct and immense necropolises.

Discovery of the ruined city by travellers in the 17th and 18th centuries resulted in its subsequent influence on architectural styles.

Until recently Palmyra was occupied by ISIS or ISIL or IS (depending on what the group is being called today). A March 31, 2016 news item on phys.org presents a perspective on the city and cultural heritage in a time of strife,

The destruction at the ancient city of Palmyra symbolises the suffering of the Syrian people at the hands of the terrorist group known as Islamic State (IS). Palmyra was a largely Roman city located at a desert oasis on a vital crossroad, and “one of the most important cultural centres of the ancient world”. Its remarkable preservation highlighted an intermingling of cultures that today, as then, came to stand for the tolerance and multiculturalism that pre-conflict Syria was renowned for -– tolerance that IS seeks to eradicate.

A March 31, 2016 essay by Emma Cunliffe (University of Oxford) for The Conversation, which originated the news item, expands on the theme,

Early in the conflict, the area was heavily fortified. Roads and embankments were dug through the necropolises and the Roman walls, and the historic citadel defences were upgraded. Yet the terrorists occupied and desecrated the city from May 2015, systematically destroying monuments such as the Temple of Baalshamin, the Temple of Bel, seven tower tombs, a large Lion goddess statue and two Islamic shrines. They ransacked the museum, tortured and executing the former site director Khaled al-Asaad in search of treasure to sell. According to satellite imagery analysis the site was heavily looted throughout it all.

Now the city has been recaptured, the first damage assessments are underway, and Syrian – and international – attention is already turning to restoration. This work will be greatly aided by the Syrians who risked their lives to transport the contents of the Palmyra museum to safety. The last truck pulled out as IS arrived, with bullets whizzing past.

There is a contrasting view as to how much destruction occurred from a March 29, 2016 essay by Paul Rogers (University of Bradford) for The Conversation,

Syrian Army units have taken back the ancient city of Palmyra from Islamic State. The units are now also trying to extend their control to include al-Qaryatain, to the south west of Palmyra, and Sukhnah, to the north east.

There are indications that the damage done to the ancient world heritage site which lies just outside Palmyra has been much less than feared. It may even have been limited to the destruction of two or three individual ruins – certainly important in their own right but just a small part of a huge complex that stretches over scores of hectares.

Written before some of the latest events, Rogers’ perspective is one of military tactics and strategy which contrasts with Cunliffe’s cultural heritage perspective. Like the answers to the classic question ‘Is the glass is half empty or is the glass is half full?’, both are correct, in their way.

Getting back to the cultural heritage aspect, Cunliffe outlines how Syrians and others in the international community are attempting to restore Palmyra, from her March 31, 2016 essay (Note: Links have been removed),

Even as they were displaced, Syrians have worked to keep a detailed memory of the city alive. Syrian artists created artworks depicting the destruction. In a Jordanian camp, refugees made miniature models of the city and other cultural sites, even measuring out the number and position of Palmyra’s columns from photographs.

The international community is also playing its part. Groups like UNOSAT [UNITAR’s Operational Satellite Applications Programme], the UN’s satellite imagery analysts have used satellite imagery to monitor the damage. On the ground, Syrian-founded NGOs like APSA [Association for the Protection Syrian Archaeology] have linked with universities to assess the site. Groups such as NewPalmyra and Palmyra 3D Model are using the latest technology to create open-access 3D computer models from photographs.

Others have gone even further. The Million Image Database Project at the Oxford Institute for Digital Archaeology distributed cameras to volunteers across the Middle East to collect 3D photos of sites. As well as creating 3D models, they will recreate full-scale artefacts, sites, and architectural features using their own cement-based 3D printing techniques. This will start with a recreation of the arch from Palmyra’s Temple of Bel, due to be unveiled in London in April 2016.

Here’s an artistic representation of the destruction,

A depiction of the destruction. Humam Alsalim and Rami Bakhos

A depiction of the destruction. Humam Alsalim and Rami Bakhos

Of course, there are some ethical issues about the restoration being raised, from Cunliffe’s March 31, 2016 essay (Note: Links have been removed),

It wouldn’t be the first time such large-scale restoration has been undertaken. Historic central Warsaw, for example, was destroyed during World War II, and was almost completely reconstructed and is now a World Heritage site. Reconstruction is costly, but might be accomplished more quickly and cheaply using new digital techniques, showing the world that Syria values its cultural heritage.

But many argue that 3D printing fails to capture the authenticity of the original structures, amounting to little more than the Disneyfication of heritage. They also point out that the fighting is still ongoing: 370,000 Syrians are dead, millions are displaced, and perhaps 50%-70% of the nearby town has been destroyed. Given the pressing humanitarian needs, stabilisation alone should be the priority for now.

Rebuilding also fails to redress the loss caused by the extensive looting of the site, focusing only on the dramatically destroyed monuments. Perhaps most importantly, its worth asking whether returning Palmyra exactly to its pre-conflict state denies a major chapter of its history? There needs to be a wide-ranging discussion on the priorities for the immediate future and the nature of any future reconstruction.

While I grasp most of the arguments I’m not sure why 3D printing raises a greater ethical issue, “… many argue that 3D printing fails to capture the authenticity of the original structures, amounting to little more than the Disneyfication of heritage … .” Couldn’t you say that about any form of restoration? Certainly, I was disconcerted when I saw the Sphinx in Cairo in real life where the restoration is quite obvious from angles not usually seen in tourist pictures.

More tangentially, how big is the 3D printer? If memory serves, building materials from ancient times were often large blocks of stone.

Getting back to the point, both Cunliffe’s and Rogers’ essays are worth reading in their entirety if you have the time. And since those essays have been written there has been an update for Associated Press in an April 1, 2016 article by Albert Aji on phys.org. Apparently, the IS retreat included time to plant thousands of mines throughout Palmyra with trees, doors, animals and more being booby-trapped and, now, being detonated by the Syrian army.

One final comment, The booby-trapping reminded me of a scene in the English Patient (movie) when the allies have won the war, the Germans have withdrawn and British and Canadian soldiers have liberated a town in Italy. They celebrate that night and one exuberant Brit soldier climbs a flagpole (I think) and is killed because the Germans had booby-trapped the top of the flagpole. Some years ago, a friend of mine was peacekeeper in Croatia and he said that everything was booby-trapped, flagpoles, mailboxes, cemetery markers, etc. He never said anything much more about but I have the impression it was demoralizing and stressful. I think the discussion about restoration and the artwork produced by Syrians in response to the happenings in Palmyra are an important way to counteract demoralization and stress. Whether money should be spent on restoration or all of it dedicated to pressing humanitarian needs is a question for other people to answer but a society without art and culture is one that is dying so it is heartening to note the vibrancy in Syria.

ETA April 19, 2016: Palmyra’s Arch of Triumph has been successfully replicated and is standing in London, UK according to an April 19, 2016 news item on phys.org. The replica is about 2/3 the size of the original. No reason for the size change is given in the Associated Press article. The arch scheduled to remain in London for a few more days before moving to New York, Dubai, and other destinations before arriving in Palmyra.

Motor proteins have a stiff-legged walk

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An April 23, 2015 news item on Nanowerk calls to mind Monty Python and its Ministry of Silly Walks,

The ‘stiff-legged’ walk of a motor protein along a tightrope-like filament has been captured for the first time.

Because cells are divided in many parts that serve different functions some cellular goodies need to be transported from one part of the cell to another for it to function smoothly. There is an entire class of proteins called ‘molecular motors’, such as myosin 5, that specialise in transporting cargo using chemical energy as fuel.

Remarkably, these proteins not only function like nano-scale lorries, they also look like a two-legged creature that takes very small steps. But exactly how Myosin 5 did this was unclear.

For anyone unfamiliar with The Ministry of Silly Walks (from its Wikipedia entry; Note: Links have been removed),

“The Ministry of Silly Walks” is a sketch from the Monty Python comedy troupe’s television show Monty Python’s Flying Circus, season 2, episode 14, which is entitled “Face the Press”.

Here’s an image from the sketch, which perfectly illustrates a stiff-legged walk,

John Cleese as a Civil Servant in the Ministry of Silly Walks. Screenshot from Monty Python's Flying Circus episode, Dinsdale (Alternate episode title: Face the Press). Ministry_of_Silly_Walks.jpg ‎(300 × 237 pixels, file size: 14 KB, MIME type: image/jpeg) [downloaded from http://en.wikipedia.org/wiki/File:Ministry_of_Silly_Walks.jpg]

John Cleese as a Civil Servant in the Ministry of Silly Walks. Screenshot from Monty Python’s Flying Circus episode, Dinsdale (Alternate episode title: Face the Press). Ministry_of_Silly_Walks.jpg ‎(300 × 237 pixels, file size: 14 KB, MIME type: image/jpeg) [downloaded from http://en.wikipedia.org/wiki/File:Ministry_of_Silly_Walks.jpg]

As far as I can tell, the use of this image would fall under the notion of ‘fair dealing‘ as it’s called in Canada.

Getting back to the Nanowerk news item, it started life as a University of Oxford Science blog April 23, 2015 posting  by Pete Wilton (Note: A link has been removed),

The motion of myosin 5 has now been recorded by a team led by Oxford University scientists using a new microscopy technique that can ‘see’ tiny steps of tens of nanometres captured at up to 1000 frames per second. The findings are of interest for anyone trying to understand the basis of cellular function but could also help efforts aimed at designing efficient nanomachines.

‘Until now, we believed that the sort of movements or steps these proteins made were random and free-flowing because none of the experiments suggested otherwise,’ said Philipp Kukura of Oxford University’s Department of Chemistry who led the research recently reported in the journal eLife. ‘However, what we have shown is that the movements only appeared random; if you have the capability to watch the motion with sufficient speed and precision, a rigid walking pattern emerges.’

One of the key problems for those trying to capture proteins on a walkabout is that not only are these molecules small – with steps much smaller than the wavelength of light and therefore the resolution of most optical microscopes – but they are also move very quickly.

Philipp describes how the team had to move from the microscope equivalent of an iPhone camera to something more like the high speed cameras used to snap speeding bullets. Even with such precise equipment the team had to tag the ‘feet’ of the protein in order to precisely image its gait: one foot was tagged with a quantum dot, the other with a gold particle just 20 nanometres across. (Confusingly, technically speaking, these ‘feet’ are termed the ‘heads’ of the protein because they bind to the actin filament).

I recommend reading Wilton’s post in its entirety. Meanwhile, here’s a 12 secs. video illustrating the motor protein’s stiff-legged walk,

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

Structural dynamics of myosin 5 during processive motion revealed by interferometric scattering microscopy by Joanna Andrecka, Jaime Ortega Arroyo, Yasuharu Takagi, Gabrielle de Wit, Adam Fineberg, Lachlan MacKinnon, Gavin Young, James R Sellers, & Philipp Kukura. eLife 2015;4:e05413 DOI: http://dx.doi.org/10.7554/eLife.05413Published March 6, 2015

This paper is open access.

As for silly walks, there is more than one version of the sketch with John Cleese on YouTube but I was particularly taken with this public homage which took place in Brno (Czech Republic) in Jan. 2013,

Enjoy!

Nanotechnology and infinite risk: Global challenges report on 12 risks that threaten human civilisation

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The Global Challenges Foundation recently released a report which lists 12 global risks (from the Global Challenges: 12 Risks ,that threaten human civilisation report webpage,

This report has, to the best of the authors’ knowledge, created the first list of global risks with impacts that for all practical purposes can be called infinite. It is also the first structured overview of key events related to such risks and has tried to provide initial rough quantifications for the probabilities of these impacts.

With such a focus it may surprise some readers to find that the report’s essential aim is to inspire action and dialogue as well as an increased use of the methodologies used for risk assessment.

The real focus is not on the almost unimaginable impacts of the risks the report outlines. Its fundamental purpose is to encourage global collaboration and to use this new category of risk as a driver for innovation.

…

The 12 global risks that threaten human civilisation are:

Current risks

1. Extreme Climate Change
2. Nuclear War
3. Ecological Catastrophe
4. Global Pandemic
5. Global System Collapse

Exogenic risks

6. Major Asteroid Impact
7. Supervolcano

Emerging risks

8. Synthetic Biology
9. Nanotechnology
10. Artificial Intelligence
11. Uncertain Risks

Global policy risk

12. Future Bad Global Governance

The report is fairly new as it was published in February 2015. Here’s a summary of the nanotechnology risk from the report‘s executive summary,

Atomically precise manufacturing, the creation of effective, high- throughput manufacturing processes that operate at the atomic or molecular level. It could create new products – such as smart or extremely resilient materials – and would allow many different groups or even individuals to manufacture a wide range of things. This could lead to the easy construction of large arsenals of conventional or more novel weapons made possible by atomically precise manufacturing. AI is the intelligence exhibited by machines or software, and the branch of computer science that develops machines and software with human-level intelligence. The field is often defined as “the study and design of intelligent agents”, systems that perceive their environment and act to maximise their chances of success. Such extreme intelligences could not easily be controlled (either by the groups creating them, or by some international regulatory regime), and would probably act to boost their own intelligence and acquire maximal resources for almost all initial AI motivations.

Of particular relevance is whether nanotechnology allows the construction of nuclear bombs. But many of the world’s current problems may be solvable with the manufacturing possibilities that nanotechnology would offer, such as depletion of natural resources, pollution, climate change, clean water and even poverty. Some have conjectured special self-replicating nanomachines which would be engineered to consume the entire environment. [grey goo and/or green goo scenarios; emphasis mine] The misuse of medical nanotechnology is another risk scenario. [p. 18 print version; p. 20 PDF]

I was a bit surprised to see the ‘goo’ scenarios referenced since Eric Drexler one of the participants and the person who first posted the ‘grey goo’ scenario (a green goo scenario was subsequently theorized by Robert Freitas)  has long tried to dissociate himself from it.

The report lists the academics and experts (including Drexler) who helped to produce the report,

Dr Nick Beckstead, Research Fellow, Future of Humanity Institute, Oxford Martin School & Faculty of Philosophy, University of Oxford

Kennette Benedict, Executive Director and Publisher of the Bulletin of the Atomic Scientists

Oliver Bettis, Pricing Actuary, Munich RE and Fellow of the Chartered Insurance Institute and the Institute & Faculty of Actuaries

Dr Eric Drexler, Academic Visitor, Future of Humanity Institute, Oxford Martin School & Faculty of Philosophy, University of Oxford [emphasis mine]

Madeleine Enarsson , Transformative Catalyst, 21st Century Frontiers

…

Pan Jiahua, Director of the Institute for Urban and Environmental Studies, Chinese Academy of Social Sciences (CASS); Professor of economics at CASS; Vice-President Chinese Society for Ecological Economics; Member of the National Expert Panel on Climate Change and National Foreign Policy Advisory Committee, China

…

Jennifer Morgan, Founder & Co-Convener, The Finance Lab
James Martin Research Fellow, Future of Humanity Institute, Oxford Martin School & Faculty of Philosophy, University of Oxford

…

Andrew Simms, Author, Fellow at the New Economics Foundation and Chief Analyst at Global Witness

…

Nathan Wolfe, Director of Global Viral and the Lorry I. Lokey Visiting Professor in Human Biology at Stanford University

Liang Yin, Investment Consultant at Towers Watson [p. 1 print versioin; p. 3 PDF]

While I don’t recognize any names other that Drexler’s, it’s an interesting list albeit with a preponderance of individuals associated with the University of Oxford .

The Feb. 16, 2015 Global Challenges Foundation press release announcing the risk report includes a brief description of the foundation and, I gather, a sister organization at Oxford University,

About the Global Challenges Foundation
The Global Challenges Foundation works to raise awareness of the greatest threats facing humanity and how these threats are linked to poverty and the rapid growth in global population. The Global Challenges Foundation was founded in 2011 by investor László Szombatfalvy.

About Oxford University’s Future of Humanity Institute
The Future of Humanity Institute is a multidisciplinary research institute at the University of Oxford. It enables a select set of leading intellectuals to bring the tools of
mathematics, philosophy, and science to bear on big-picture questions about humanity and its prospects. The Institute belongs to the Faculty of Philosophy and is affiliated with
the Oxford Martin School.

The report is 212 pp (PDF), Happy Reading!

Molecular robots (nanobots/nanorobots): a promising start at Oxford University

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‘Baby steps’ is how they are describing the motion and the breakthrough in functional molecular robots at the University of Oxford. From a Dec. 11, 2014 news item on phys.org,

A walking molecule, so small that it cannot be observed directly with a microscope, has been recorded taking its first nanometre-sized steps.

It’s the first time that anyone has shown in real time that such a tiny object – termed a ‘small molecule walker’ – has taken a series of steps. The breakthrough, made by Oxford University chemists, is a significant milestone on the long road towards developing ‘nanorobots’.

‘In the future we can imagine tiny machines that could fetch and carry cargo the size of individual molecules, which can be used as building blocks of more complicated molecular machines; imagine tiny tweezers operating inside cells,’ said Dr Gokce Su Pulcu of Oxford University’s Department of Chemistry. ‘The ultimate goal is to use molecular walkers to form nanotransport networks,’ she says.

A Dec. 10, 2014 University of Oxford science blog post by Pete Wilton, which originated the news item, describes one of the problem with nanorobots,

However, before nanorobots can run they first have to walk. As Su explains, proving this is no easy task.

For years now researchers have shown that moving machines and walkers can be built out of DNA. But, relatively speaking, DNA is much larger than small molecule walkers and DNA machines only work in water.

The big problem is that microscopes can only detect moving objects down to the level of 10–20 nanometres. This means that small molecule walkers, whose strides are 1 nanometre long, can only be detected after taking around 10 or 15 steps. It would therefore be impossible to tell with a microscope whether a walker had ‘jumped’ or ‘floated’ to a new location rather than taken all the intermediate steps.

The post then describes how the researchers solved the problem,

… Su and her colleagues at Oxford’s Bayley Group took a new approach to detecting a walker’s every step in real time. Their solution? To build a walker from an arsenic-containing molecule and detect its motion on a track built inside a nanopore.

Nanopores are already the foundation of pioneering DNA sequencing technology developed by the Bayley Group and spinout company Oxford Nanopore Technologies. Here, tiny protein pores detect molecules passing through them. Each base disrupts an electric current passed through the nanopore by a different amount so that the DNA base ‘letters’ (A, C, G or T) can be read.

In this new research, they used a nanopore containing a track formed of five ‘footholds’ to detect how a walker was moving across it.

‘We can’t ‘see’ the walker moving, but by mapping changes in the ionic current flowing through the pore as the molecule moves from foothold to foothold we are able to chart how it is stepping from one to the other and back again,’ Su explains.

To ensure that the walker doesn’t float away, they designed it to have ‘feet’ that stick to the track by making and breaking chemical bonds. Su says: ‘It’s a bit like stepping on a carpet with glue under your shoes: with each step the walker’s foot sticks and then unsticks so that it can move to the next foothold.’ This approach could make it possible to design a machine that can walk on a variety of surfaces.

There is a video illustrating the molecular walker’s motion, (courtesy University of Oxford),

There is as noted in Wilton’s post, more work to do,

It’s quite an achievement for such a tiny machine but, as Su is the first to admit, there are many more challenges to be overcome before programmable nanorobots are a reality.

‘At the moment we don’t have much control over which direction the walker moves in; it moves pretty randomly,’ Su tells me. ‘The protein track is a bit like a mountain slope; there’s a direction that’s easier to walk in so walkers will tend to go this way. We hope to be able to harness this preference to build tracks that direct a walker where we want it to go.’

The next challenge after that will be for a walker to make itself useful by, for instance, carrying a cargo: there’s already space for it to carry a molecule on its ‘head’ that it could then take to a desired location to accomplish a task.

Su comments: ‘We should be able to engineer a surface where we can control the movement of these walkers and observe them under a microscope through the way they interact with a very thin fluorescent layer. This would make it possible to design chips with different stations with walkers ferrying cargo between these stations; so the beginnings of a nanotransport system.’

These are the first tentative baby steps of a new technology, but they promise that there could be much bigger strides to come.

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

Continuous observation of the stochastic motion of an individual small-molecule walker by Gökçe Su Pulcu, Ellina Mikhailova, Lai-Sheung Choi, & Hagan Bayley. Nature Nanotechnology (2014) doi:10.1038/nnano.2014.264 Published online 08 December 2014

This paper is behind a paywall.

Treatment for patients infected with the ebola virus (a response to crisis in West African countries)

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I’ve not actively kept up with the situation in the West African countries suffering an outbreak of the ebola virus other than to note that it is ongoing. My Aug. 15, 2014 post provides a snapshot of the situation and various new treatments, including one based on tobacco, which could be helpful but appeared not to have been tested and/or deployed. There was a lot of secrecy (especially from Medicago, a Canadian company) regarding the whole matter of treatments and vaccines.

There seem to have been some new developments on the treatment side, involving yet another Canadian company, Tekmira, according to a Sept. 23, 2013 news item on Azonano,

Tekmira Pharmaceuticals Corporation, a leading developer of RNA interference (RNAi) therapeutics, today announced that the FDA [US Food and Drug Administration] has authorized Tekmira to provide TKM-Ebola for treatment under expanded access protocols to subjects with confirmed or suspected Ebola virus infections.

A Sept. 22, 2014 Tekmira news release, which originated the news item, expands on the topic of regulatory issues associated with bringing this treatment to the areas suffering the outbreak,

“Tekmira is reporting that an appropriate regulatory and clinical framework is now in place to allow the use of TKM-Ebola in patients. We have worked with the FDA and Health Canada to establish this framework and a treatment protocol allowing us to do what we can to help these patients,” said Dr. Mark J. Murray Tekmira’s President and CEO.

“We have insisted on acting responsibly in the interest of patients and our stakeholders,” added Dr. Murray. “Today we are reporting that, working closely with regulators in the United States and Canada, we have established a framework for TKM-Ebola use in multiple patients. In the US, the FDA has granted expanded access use of TKM-Ebola under our Investigational New Drug application (IND) and Health Canada has established a similar framework, both of which allow the use of our investigational therapeutic in more patients.”

“We have already responded to requests for the use of our investigational agent in several patients under emergency protocols, in an effort to help these patients, a goal we share with the FDA and Health Canada. TKM-Ebola has been administered to a number of patients and the repeat infusions have been well tolerated. However, it must be kept in mind that any uses of the product under expanded access, does not constitute controlled clinical trials. These patients may be infected with a strain of Ebola virus which has emerged subsequent to the strain that our product is directed against, and physicians treating these patients may use more than one therapeutic intervention in an effort to achieve the best outcome,” said Dr. Murray. “Our TKM-Ebola drug supplies are limited, but we will continue to help where we can, as we continue to focus on the other important objectives we have to advance therapies to meet the unmet needs of patients.”

TKM-Ebola is an investigational therapeutic, being developed under an FDA approved IND, which is currently the subject of a partial clinical hold under which the FDA has allowed the potential use of TKM-Ebola in individuals with a confirmed or suspected Ebola virus infection.

About FDA Expanded Access Program

Expanded access is the use of an investigational drug outside of a clinical trial to treat a patient, with a serious or immediately life-threatening disease or condition, who has no comparable or satisfactory alternative treatment options. FDA regulations allow access to investigational drugs for treatment purposes on a case-by-case basis for an individual patient, or for intermediate-size groups of patients with similar treatment needs who otherwise do not qualify to participate in a clinical trial. (Source: www.fda.com)

About TKM-Ebola, an Anti-Ebola Virus RNAi Therapeutic

TKM-Ebola, an anti-Ebola virus RNAi therapeutic, is being developed under a $140 million contract with the U.S. Department of Defense’s Medical Countermeasure Systems BioDefense Therapeutics (MCS-BDTX) Joint Product Management Office. Earlier preclinical studies were published in the medical journal The Lancet and demonstrated that when siRNA targeting the Ebola virus and delivered by Tekmira’s LNP [Lipid Nanoparticle] technology were used to treat previously infected non-human primates, the result was 100 percent protection from an otherwise lethal dose of Zaire Ebola virus (Geisbert et al., The Lancet, Vol. 375, May 29, 2010). In March 2014, Tekmira was granted a Fast Track designation from the U.S. Food and Drug Administration for the development of TKM-Ebola.

About Joint Project Manager Medical Countermeasure Systems (JPM-MCS)

This work is being conducted under contract with the U.S. Department of Defense Joint Project Manager Medical Countermeasure Systems (JPM-MCS). JPM-MCS, a component of the Joint Program Executive Office for Chemical and Biological Defense, aims to provide U.S. military forces and the nation with safe, effective, and innovative medical solutions to counter chemical, biological, radiological, and nuclear threats. JPM-MCS facilitates the advanced development and acquisition of medical countermeasures and systems to enhance biodefense response capability. For more information, visit www.jpeocbd.osd.mil.

About Tekmira

Tekmira Pharmaceuticals Corporation is a biopharmaceutical company focused on advancing novel RNAi therapeutics and providing its leading lipid nanoparticle (LNP) delivery technology to pharmaceutical partners. Tekmira has been working in the field of nucleic acid delivery for over a decade and has broad intellectual property covering LNPs. Further information about Tekmira can be found at www.tekmira.com. Tekmira is based in Vancouver, B.C. Canada.

Forward-Looking Statements and Information

This news release contains “forward-looking statements” or “forward-looking information” within the meaning of applicable securities laws (collectively, “forward-looking statements”). Forward-looking statements in this news release include statements about Tekmira’s strategy, future operations, clinical trials, prospects and the plans of management; an appropriate regulatory and clinical  framework for emergency use of TKM-Ebola in subjects with confirmed or suspected Ebola infections; FDA grant of expanded access use of TKM-Ebola under Tekmira’s IND; Health Canada’s establishment of a similar framework for TKM-Ebola; Tekmira’s response to requests for the use of TKM-Ebola in several patients under emergency protocols and the results thereon; the current supply of TKM-Ebola drug; the partial clinical hold on the TKM-Ebola IND by the FDA (enabling the potential use of TKM-Ebola in individuals with a confirmed or suspected Ebola virus infection); the quantum value of the contract with the JPM-MCS; and Fast Track designation from the FDA for the development of TKM-Ebola.

With respect to the forward-looking statements contained in this news release, Tekmira has made numerous assumptions regarding, among other things, the clinical framework for emergency use of TKM-Ebola. While Tekmira considers these assumptions to be reasonable, these assumptions are inherently subject to significant business, economic, competitive, market and social uncertainties and contingencies.

Additionally, there are known and unknown risk factors which could cause Tekmira’s actual results, performance or achievements to be materially different from any future results, performance or achievements expressed or implied by the forward-looking statements contained herein. Known risk factors include, among others: TKM-Ebola may not prove to be effective in the treatment of Ebola infection under the emergency use framework, or at all; any uses of TKM-Ebola under emergency INDs are not controlled trails, and TKM-Ebola may be used on Ebola strains that have diverged from the strain to which TKM-Ebola is directed, and physicians treating patients may use more than one therapeutic intervention in addition to TKM-Ebola; the current supply of TKM-Ebola is limited, and Tekmira may not be able to respond to future requests for help in the current Ebola outbreak; the FDA may not remove the partial clinical hold on the TKM-Ebola IND; the FDA may refuse to approve Tekmira’s products, or place restrictions on Tekmira’s ability to commercialize its products; anticipated pre-clinical and clinical trials may be more costly or take longer to complete than anticipated, and may never be initiated or completed, or may not generate results that warrant future development of the tested drug candidate; and Tekmira may not receive the necessary regulatory approvals for the clinical development of Tekmira’s products.

A more complete discussion of the risks and uncertainties facing Tekmira appears in Tekmira’s Annual Report on Form 10-K and Tekmira’s continuous disclosure filings, which are available at www.sedar.com or www.sec.gov. All forward-looking statements herein are qualified in their entirety by this cautionary statement, and Tekmira disclaims any obligation to revise or update any such forward-looking statements or to publicly announce the result of any revisions to any of the forward-looking statements contained herein to reflect future results, events or developments, except as required by law.

In the midst of all those ‘cover your rear end’ statements to investors, it’s easy to miss the fact that people are actually being treated and the results are promising, if not guaranteed,

Tekmira has distributed a Sept. 23, 2014 news release touting its membership in a new consortium, which suggests that in parallel with offering treatment, human clinical trials will  also be conducted,

Tekmira Pharmaceuticals Corporation (Nasdaq:TKMR) (TSX:TKM), a leading developer of RNA interference (RNAi) therapeutics, today reported that it is collaborating with an international consortium to provide an RNAi based investigational therapeutic for expedited clinical studies in West Africa.

Led by Dr. Peter Horby of the Centre for Tropical Medicine and Global Health at the University of Oxford and the International Severe Acute Respiratory and Emerging Infection Consortium (ISARIC), the consortium includes representatives from the World Health Organization (WHO), US Centers for Disease Control, Médecins Sans Frontières – Doctors without Borders (MSF), ISARIC, and Fondation Mérieux, among others.

The Wellcome Trust has announced it has awarded £3.2 million to the consortium to fund this initiative. The award will include funds for the manufacture of investigational therapeutics as well as the establishment of an operational clinical trials platform in two or more Ebola Virus Disease (EVD) treatment centers in West Africa. RNAi has been prioritized as an investigational therapeutic and may be selected for clinical trials at these centers.

The objective of the clinical trials is to assess the efficacy and safety of promising therapeutics and vaccines, reliably and safely, in patients with EVD by adopting strict protocols that comply with international standards.  It is hoped this initiative will permit the adoption of safe and effective interventions rapidly.

The genetic sequence of the Ebola virus variant responsible for the ongoing outbreak in West Africa is now available. Under this program, Tekmira will produce an RNAi based product specifically targeting the viral variant responsible for this outbreak.  The ability to rapidly and accurately match the evolving genetic sequences of emerging infectious agents is one of the powerful features of RNAi therapeutics.

“We commend the Wellcome Trust for their leadership in providing the necessary funds to launch and expedite this ground breaking initiative. We are gratified that RNAi has been prioritized as a potential investigational therapeutic to assist in the ongoing public health and humanitarian crisis in Africa,” said Dr. Murray, Tekmira’s President and CEO.

“We are an active collaborator in this consortium and through our ongoing dialogue with the WHO, NGOs and governments in various countries; we have been discussing the creation of appropriate clinical and regulatory frameworks for the potential use of investigational therapeutics in Africa. This initiative goes a long way towards achieving this aim.  Many complex decisions remain to fully implement this unique clinical trial platform.  At this time, there can be no assurances that our product will be selected by the consortium for clinical trials in Africa,” said Dr. Murray.

About Wellcome Trust

The Wellcome Trust is the largest charity in the UK. It funds innovative biomedical research, in the UK and internationally, spending over £600 million each year to support the brightest scientists with the best ideas. The Wellcome Trust supports public debate about biomedical research and its impact on health and wellbeing. For more information, visit www.wellcome.ac.uk

I’m glad they’re being careful while giving people treatment, i. e., trying to do something rather than waiting to conduct human clinical trials as has sometimes been the case in the past. This business of running the trials almost parallel to offering treatment suggests an agility not often associated with the international health care community.

ETA Sept. 23 2014 1200 hours PDT: For more information about the status of the Ebola outbreak read Tara Smith’s Sept. 22, 2014 article Slate titled, Here’s Where We Stand With Ebola; Even experienced international disaster responders are shocked at how bad it’s gotten (Note: Links have been removed).

Now, terms like “exponential spread” are being thrown around as the epidemic continues to expand more and more rapidly. Just last week, an increase of 700 new cases was reported, and the case count is now doubling in size approximately every three weeks.

…

A Doctors Without Borders worker in Monrovia, Liberia, named Jackson Naimah describes the situation in his home country, noting that patients are literally dying at the front door of his treatment center because it lacks patient beds and assistance; the sufferers are left to die a “horrible, undignified death” and potentially infect others as they do so: …

…

… Health care workers who are treating the sick are dying because they also lack basic protective equipment, or because they have been so overwhelmed by taking care of the ill and dying that they begin to make potentially fatal errors. They have gone on strike in Liberia because they are not being adequately protected or even paid for their risky service.

…

Fear and misinformation are as deadly as the virus itself. Eight Ebola workers were recently murdered in Guinea, in the area where the virus first came to the world’s attention in March. Liberia’s largest newspaper featured a story describing Ebola as a man-made virus being purposely unleashed upon Africans by Western pharmaceutical companies. Reports abound of doctors and other workers being chased away, sometimes violently, by fearful families. …

It’s not a pleasant read but, I think, a necessary one. For anyone who may think the panic and fear are unique to this situation, I once worked with a nurse who described being lifted by her neck after someone came through the door of a clinic demanding a vaccine and had been refused. He was in such a panic and so fearful he wasn’t going to take a ‘no’. The incident took place in Vancouver (Canada) in a ‘nice’ part of town.

ETA Sept. 24, 2014: Kelly Grant has written a Sept. 22, 2014 article for the Globe and Mail which provides more information about Tekmira, some of which contradicts the details I have here about TKM-Ebola and clinical trials in Africa although the key points remain the same. She also provides more information about the ZMapp therapy (mentioned in my Aug. 15, 2014 post) noting yet a third Canadian connection.* Canada’s National Microbiology Laboratory was somehow involved in developing ZMApp, unfortunately, Grant does not or is not able to provide more details about that involvement.

ETA Oct. 16, 2014: David Bruggeman recommends a digital journalism site Ebola Deeply for some in depth reporting in his Oct. 16, 2014 posting.

* This sentence “She also provides more information about the ZMapp therapy mentioned in my Aug. 15, 2014 post mentioning yet a third Canadian connection.” was altered for grammatical purposes on Dec. 4, 2014.

University of Oxford (UK)’s wider aspects of nanotechnology online course

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Despite its designation as a summer school programme, this University of Oxford’s online nanotechnology course is being offered from Oct. 13 – Nov. 30, 2014. Here’s more from the University of Oxford, Dept. of Continuing Studies, The Wider Contest of Nanotechnology webpage,

Overview

Nanotechnology is the identification, application and use of novel behaviour that occurs at the nanoscale to solve real-world problems. The discipline requires a breadth of understanding that is much wider than just the equations and scientific principles that underlie that behaviour. This introductory course gives an overview of the current state of nanotechnology as well as introducing the implications of these new technologies for safety, regulation, and innovation. The course provides an overview of the societal and environmental implications of nanotechnology.

The Wider Context of Nanotechnology online course can be taken alone, with or without academic credit, or as part of the Postgraduate Certificate in Nanotechnology.

…

The result has been a high degree of confusion at all levels of society as to the ethics, safety and business implications of this emerging series of technologies. The course addresses these issues and others in emphasising the interdisciplinary nature of nanotechnology. This is important because students who specialise in nanotechnology must be trained to appreciate a range of issues beyond the confines of pure science. Nanotechnology has applications in a broad range of fields and sectors of society. A student trained in electrical engineering, for example, who goes on to specialise in nanotechnology, may undertake a research project developing nanosensors that will be implanted in human subjects. He or she will therefore need to develop new skills to appreciate the broader ethical, societal and environmental implications of such research.

The development of interdisciplinary skills involves not only learning methods of reasoning and critical thinking, but also gaining experience with the dynamics and development of effective multi-disciplinary function. Technologists must become comfortable addressing various issues as an integral part of doing advanced research in a team that might draw upon the expertise of not only engineers, but also biologists, doctors, lawyers and business people. As the project evolves knowledge of the place of nanotechnology in business becomes increasingly important. This course teaches an understanding of the basic workings of how nanotechnology innovation is exploited, together with an understanding of the dynamics of entrepreneurship

Here are some details about the Programme Director and Tutor,

Dr Christiane Norenberg

Role: Director

Christiane is the Nanotechnology HEIF Manager at the University of Oxford’s Begbroke Science Park. She received her DPhil in Materials Science from the University of Oxford in 1998 and continued with postdoctoral research. In 2001, Christiane was awarded the Royal Society Dorothy Hodgkin Fellowship for her work on the growth and characterisation of nanostructures on semiconductor surfaces. After a period as a lecturer at the Multidisciplinary Nanotechnology Centre at Swansea University, Christiane returned to Oxford in 2007 to take up her present post.

Her interests and expertise are in the areas of surface science, growth and characterisation of nanostructures on surfaces, and nanotechnology in general. Christiane also teaches nanoscience and materials science at undergraduate and postgraduate level.

Dr Keith Simons

Role: Tutor

Dr Keith Simons, a chemist by training, is an independent innovation consultant who works as an interim manager in business development and fundraising for high-technology start-up organisations. He also works for regional, national and European governments in evaluation and monitoring of publicly-funded research. Keith is also the tutor for our first course to feature Adobe Connect Professional, the Postgraduate Certificate in Nanotechnology.

He has previously been the Business Development Manager for the Crystal Faraday Partnership, a not-for-profit organisation, backed by the British government and responsible for advancing innovation in Green Chemical Technologies for the chemical and allied industries. Prior to Crystal Faraday, he worked for Avantium Technologies in Amsterdam, a start-up company that developed high throughput technologies for the chemicals and pharmaceutical industries. This built upon his experience as development chemist at Johnson Matthey in the UK where he developed accelerated techniques for catalyst development and process optimisation for pharmaceutical manufacture.

Keith has degrees from the Universities of Hull and Liverpool. He has also performed postdoctoral research at the ETH, Zurich.

I notice Dr. Norenberg received a ‘Dorothy Hodgkin’ fellowship. Coincidentally, I mentioned a play about Dorothy Hodgkin and her friendship with Margaret Thatcher (Hodgkin’s former student and a UK Prime Minister) to be broadcast on BBC 4 later this week on Aug. 20, 2014. Scroll down about 50% of the way if you want to read my Aug. 15, 2014 posting about the play and other arts and sciences news.

Getting back to the wider implications of nanotechnology, the course fee is £2400.00 and it is possible to apply for scholarships and other financial assistance.

Wearable solar panels with perovskite

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There was a bit of a flutter online in late July 2014 about solar cell research and perovskite, a material that could replace silicon therefore making solar cells more affordable, which hopefully would lead to greater adoption of the technology. Happily, the publishers of the study seem to have reissued their news release (h/t Aug. 11, 2014 news item on Nanwerk).

From the Wiley online press release Nr. 29/2014,

Textile solar cells are an ideal power source for small electronic devices incorporated into clothing. In the journal Angewandte Chemie, Chinese scientists have now introduced novel solar cells in the form of fibers that can be woven into a textile. The flexible, coaxial cells are based on a perovskite material and carbon nanotubes; they stand out due to their excellent energy conversion efficiency of 3.3 % and their low production cost.

The dilemma for solar cells: they are either inexpensive and inefficient, or they have a reasonable efficiency and are very expensive. One solution may come from solar cells made of perovskite materials, which are less expensive than silicon and do not require any expensive additives. Perovskites are materials with a special crystal structure that is like that of perovskite, a calcium titanate. These structures are often semiconductors and absorb light relatively efficiently. Most importantly, they can move electrons excited by light for long distances within the crystal lattice before they return to their energetic ground state and take up a solid position – a property that is very important in solar cells.

A team led by Hisheng Peng at Fudan University in Shanghai has now developed perovskite solar cells in the form of flexible fibers that can be woven into electronic textiles. Their production process is relatively simple and inexpensive because it uses a solution-based process to build up the layers.

The anode is a fine stainless steel wire coated with a compact n-semiconducting titanium dioxide layer. A layer of porous nanocrystalline titanium dioxide is deposited on top of this. This provides a large surface area for the subsequent deposition of the perovskite material CH3NH3PbI3. This is followed by a layer made of a special organic material. Finally a transparent layer of aligned carbon nanotubes is continuously wound over the whole thing to act as the cathode. The resulting fiber is so fine and flexible that it can be woven into textiles.

The perovskite layer absorbs light, that excites electrons and sets them free, causing a charge separation between the electrons and the formally positively charged “holes” The electrons enter the conducting band of the compact titanium dioxide layer and move to the anode. The “holes” are captured by the organic layer. The large surface area and the high electrical conductivity of the carbon nanotube cathode aid in the rapid conduction of the charges with high photoelectric currents. The fiber solar cell can attain an energy conversion efficiency of 3.3 %, exceeding that of all previous coaxial fiber solar cells made with either dyes or polymers.

Here’s an image used in the press release illustrating the new fiber,

[downloaded from http://www.wiley-vch.de/vch/journals/2002/press/201429press.pdf]

[downloaded from http://www.wiley-vch.de/vch/journals/2002/press/201429press.pdf]

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

Integrating Perovskite Solar Cells into a Flexible Fiber by Longbin Qiu, Jue Deng, Xin Lu, Zhibin Yang, and Prof. Huisheng Peng. Angewandte Chemie International Edition DOI: 10.1002/anie.201404973 Article first published online: 22 JUL 2014

© 2014 WILEY-VCH Verlag GmbH & Co. KGaA, Weinheim

This paper is behind a paywall.

I found a second item about perovskite and solar cells in a May 16, 2014 article by Vicki Marshall for Chemistry World which discussed some research in the UK (Note: Links have been removed),

A lead-free and non-toxic alternative to current perovskite solar-cell technology has been reported by researchers in the UK: tin halide perovskite solar cells. They are also cheaper to manufacture than the silicon solar cells currently dominating the market.

Nakita Noel, part of Henry Snaith’s research team at the University of Oxford, describes how perovskite materials have caused a bit of a whirlwind since they came out in 2009: ‘Everybody that’s working in the solar community is looking to beat silicon.’ Despite the high efficiency of conventional crystalline silicon solar cells (around 20%), high production and installation costs decrease their economic feasibility and widespread use.

The challenge to find a cheaper alternative led to the development of perovskite-based solar cells, as organic–inorganic metal trihalide perovskites have both abundant and cheap starting materials. However, the presence of lead in some semiconductors could create toxicology issues in the future. As Noel puts it ‘every conference you present at somebody is bound to put up their hand and ask “What about the lead – isn’t this toxic?”’

…

Brian Hardin, co-founder of PLANT PV, US, and an expert in new materials for photovoltaic cells, says the study ‘should be considered a seminal work on alternative perovskites and is extremely valuable to the field as they look to better understand how changes in chemistry affect solar cell performance and stability.’

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

Lead-free organic–inorganic tin halide perovskites for photovoltaic applications by Nakita K. Noel, Samuel D. Stranks, Antonio Abate, Christian Wehrenfennig, Simone Guarnera, Amir-Abbas Haghighirad, Aditya Sadhana, Giles E. Eperon, Sandeep K. Pathak, Michael B. Johnston, Annamaria Petrozza, Laura M. Herza, and Henry J. Snaith. Energy Environ. Sci., 2014, Advance Article DOI: 10.1039/C4EE01076K First published online 01 May 2014

This article was open access until June 27, 2014 but now it is behind a paywall.

I notice there’s no mention of lead in the materials describing the research paper from the Chinese scientists. Perhaps they were working with lead-free materials.

The age of the ‘nano-pixel’

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As mentioned here before, ‘The Diamond Age: Or, A Young Lady’s Illustrated Primer’, a 1985 novel by Neal Stephenson featured in its opening chapter a flexible, bendable, rollable, newspaper screen. It’s one of those devices promised by ‘nano evangelists’ that never quite seems to come into existence. However, ‘hope springs eternally’ as they say and a team from the University of Oxford claims to be bringing us one step closer.

From a July 10, 2014 University of Oxford press release (also on EurekAlert but dated July 9, 2014 and on Azoanano as a July 10, 2014 news item),

A new discovery will make it possible to create pixels just a few hundred nanometres across that could pave the way for extremely high-resolution and low-energy thin, flexible displays for applications such as ‘smart’ glasses, synthetic retinas, and foldable screens.

A team led by Oxford University scientists explored the link between the electrical and optical properties of phase change materials (materials that can change from an amorphous to a crystalline state). They found that by sandwiching a seven nanometre thick layer of a phase change material (GST) between two layers of a transparent electrode they could use a tiny current to ‘draw’ images within the sandwich ‘stack’.

Here’s a series of images the researchers have created using this technology,

Still images drawn with the technology: at around 70 micrometres across each image is smaller than the width of a human hair. Courtesy University of Oxford

Still images drawn with the technology: at around 70 micrometres across each image is smaller than the width of a human hair. Courtesy University of Oxford

The press release offers a technical description,

Initially still images were created using an atomic force microscope but the team went on to demonstrate that such tiny ‘stacks’ can be turned into prototype pixel-like devices. These ‘nano-pixels’ – just 300 by 300 nanometres in size – can be electrically switched ‘on and off’ at will, creating the coloured dots that would form the building blocks of an extremely high-resolution display technology.

…

‘We didn’t set out to invent a new kind of display,’ said Professor Harish Bhaskaran of Oxford University’s Department of Materials, who led the research. ‘We were exploring the relationship between the electrical and optical properties of phase change materials and then had the idea of creating this GST ‘sandwich’ made up of layers just a few nanometres thick. We found that not only were we able to create images in the stack but, to our surprise, thinner layers of GST actually gave us better contrast. We also discovered that altering the size of the bottom electrode layer enabled us to change the colour of the image.’

The layers of the GST sandwich are created using a sputtering technique where a target is bombarded with high energy particles so that atoms from the target are deposited onto another material as a thin film.

‘Because the layers that make up our devices can be deposited as thin films they can be incorporated into very thin flexible materials – we have already demonstrated that the technique works on flexible Mylar sheets around 200 nanometres thick,’ said Professor Bhaskaran. ‘This makes them potentially useful for ‘smart’ glasses, foldable screens, windshield displays, and even synthetic retinas that mimic the abilities of photoreceptor cells in the human eye.’

Peiman Hosseini of Oxford University’s Department of Materials, first author of the paper, said: ‘Our models are so good at predicting the experiment that we can tune our prototype ‘pixels’ to create any colour we want – including the primary colours needed for a display. One of the advantages of our design is that, unlike most conventional LCD screens, there would be no need to constantly refresh all pixels, you would only have to refresh those pixels that actually change (static pixels remain as they were). This means that any display based on this technology would have extremely low energy consumption.’

The research suggests that flexible paper-thin displays based on the technology could have the capacity to switch between a power-saving ‘colour e-reader mode’, and a backlit display capable of showing video. Such displays could be created using cheap materials and, because they would be solid-state, promise to be reliable and easy to manufacture. The tiny ‘nano-pixels’ make it ideal for applications, such as smart glasses, where an image would be projected at a larger size as, even enlarged, they would offer very high-resolution.

Professor David Wright of the Department of Engineering at the University of Exeter, co-author of the paper, said: ‘Along with many other researchers around the world we have been looking into the use of these GST materials for memory applications for many years, but no one before thought of combining their electrical and optical functionality to provide entirely new kinds of non-volatile, high-resolution, electronic colour displays – so our work is a real breakthrough.’

…

The phase change material used was the alloy Ge2Sb2Te5 (Germanium-Antimony-Tellurium or GST) sandwiched between electrode layers made of indium tin oxide (ITO).

I gather the researchers are looking for investors (from the press release),

Whilst the work is still in its early stages, realising its potential, the Oxford team has filed a patent on the discovery with the help of Isis Innovation, Oxford University’s technology commercialisation company. Isis is now discussing the displays with companies who are interested in assessing the technology, and with investors.

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

An optoelectronic framework enabled by low-dimensional phase-change films by Peiman Hosseini, C. David Wright, & Harish Bhaskaran. Nature 511, 206–211 (10 July 2014) doi:10.1038/nature13487 Published online 09 July 2014

This paper is behind a paywall.

Music on the web, a spider’s web, that is

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I was expecting to see Markus Buehler and MIT (Massachusetts Institute of Technology) mentioned in this latest work on spiderwebs and music. Surprise! This latest research is from three universities in the UK as per a June 3, 2014 news item on ScienceDaily,

Spider silk transmits vibrations across a wide range of frequencies so that, when plucked like a guitar string, its sound carries information about prey, mates, and even the structural integrity of a web.

The discovery was made by researchers from the Universities of Oxford, Strathclyde, and Sheffield who fired bullets and lasers at spider silk to study how it vibrates. They found that, uniquely, when compared to other materials, spider silk can be tuned to a wide range of harmonics. The findings, to be reported in the journal Advanced Materials, not only reveal more about spiders but could also inspire a wide range of new technologies, such as tiny light-weight sensors.

A June 3, 2014 University of Oxford news release (also on EurekAlert), which originated the news item, explains the research and describes how it was conducted (firing bullets?),

‘Most spiders have poor eyesight and rely almost exclusively on the vibration of the silk in their web for sensory information,’ said Beth Mortimer of the Oxford Silk Group at Oxford University, who led the research. ‘The sound of silk can tell them what type of meal is entangled in their net and about the intentions and quality of a prospective mate. By plucking the silk like a guitar string and listening to the ‘echoes’ the spider can also assess the condition of its web.’

‘Most spiders have poor eyesight and rely almost exclusively on the vibration of the silk in their web for sensory information,’ said Beth Mortimer of the Oxford Silk Group at Oxford University, who led the research. ‘The sound of silk can tell them what type of meal is entangled in their net and about the intentions and quality of a prospective mate. By plucking the silk like a guitar string and listening to the ‘echoes’ the spider can also assess the condition of its web.’

This quality is used by the spider in its web by ‘tuning’ the silk: controlling and adjusting both the inherent properties of the silk, and the tensions and interconnectivities of the silk threads that make up the web. To study the sonic properties of the spider’s gossamer threads the researchers used ultra-high-speed cameras to film the threads as they responded to the impact of bullets. [emphasis mine] In addition, lasers were used to make detailed measurements of even the smallest vibration.

‘The fact that spiders can receive these nanometre vibrations with organs on each of their legs, called slit sensillae, really exemplifies the impact of our research about silk properties found in our study,’ said Dr Shira Gordon of the University of Strathclyde, an author involved in this research.

‘These findings further demonstrate the outstanding properties of many spider silks that are able to combine exceptional toughness with the ability to transfer delicate information,’ said Professor Fritz Vollrath of the Oxford Silk Group at Oxford University, an author of the paper. ‘These are traits that would be very useful in light-weight engineering and might lead to novel, built-in ‘intelligent’ sensors and actuators.’

Dr Chris Holland of the University of Sheffield, an author of the paper, said: ‘Spider silks are well known for their impressive mechanical properties, but the vibrational properties have been relatively overlooked and now we find that they are also an awesome communication tool. Yet again spiders continue to impress us in more ways than we can imagine.’

Beth Mortimer said: ‘It may even be that spiders set out to make a web that ‘sounds right’ as its sonic properties are intimately related to factors such as strength and flexibility.’

The research paper has not yet been published in Advanced Materials (I checked this morning, June 4, 2014).

However, there is this video from the researchers,

As for Markus Buehler’s work at MIT, you can find out more in my Nov. 28, 2012 posting, Producing stronger silk musically.