Monthly Archives: January 2015

The secret life of leaves at Vancouver’s (Canada) Café Scientifique on Jan. 27, 2015

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Vancouver’s next Café Scientifique is being held in the back room of the The Railway Club (2nd floor of 579 Dunsmuir St. [at Seymour St.], Vancouver, Canada), on Jan. 27,  2015*. Here’s the meeting description (from the Jan. 19, 2015 announcement),

Happy New Year!  We hope you all had an enjoyable and relaxing holiday season.  We’d like to send out a big thank you for your generosity in our crowdfunding campaign and your help in its promotion.  Your donations and support will help to keep us running for another year and more!

Speaking of which, our next café will happen on Tuesday, January 27th, at 7:30pm at The Railway Club. Our speaker for the evening will be Dr. Chris Muir, a Postdoctoral Fellow in the Biodiversity Research Centre at the University of British Columbia.  The title of his talk is:

More than salad: the inner lives of leaves

To most of us, leaves are the green things in a salad or the emblem on our flag. To a biologist, leaves are the critical interface between a plant and its environment. I will talk about some of the remarkable ways that leaves adapt plants to their environment. First, I will cover some basic functions that leaves perform for a plant: How do plants eat? How do plants avoid being eaten? What goes on inside a leaf? Next, I will talk about some of the unorthodox ways that leaves help plants make a living: How do plants without roots get water? Why do leaves track the sun? How did the Swiss Cheese Plant get its holes? The close connection between a leaf’s form and its function to the plant attests to the relentless action of natural selection in adapting organisms to their environment.

Muir has an eponymous website where you can find out more about his work and about him.

* Jan. 27, 2014 corrected to Jan. 27, 2015 on Feb. 12, 2015.

Islamic Educational Scientific and Cultural Organization (ISESCO) for Science and Technology and an award for Dr. Mahiran Basri

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Professor Dr Mahiran Basri of the Universiti Putra Malaysia (UPM) received an award from the Islamic Educational Scientific and Cultural Organization (ISESCO) for Science and Technology (I believe the similarity of ISESCO to UNESCO is intentional, which makes it smart marketing) for her work in oil palm research. This event has occasioned a Jan. 21, 2015 news item on phys.org,

The use of oils and fats has been successfully diversified, resulting in an innovation formulated through nanotechnology that is beneficial to pharmaceutical and cosmetics industries.

A Faculty of Science, Universiti Putra Malaysia (UPM) lecturer, Professor Dr Mahiran Basri, not only succeeded in producing new useful substances made of oils and fats for the industry, but also managed to produce them through environmental-friendly ways.

A Jan. 22, 2015 UPM news release (Malaysia is on the other side of the date line) by Azaman Zakaria, which originated the news item, describes her work and award in more detail,

“This organic synthesis uses enzymes and it is produced through nanotechnology. Our focus is to process new substances derived from oils and fats,” she said in an interview at her office.

In the field of cosmetics, for instance, she said there are antioxidants and anti-aging substances, through the use of nanotechnology, those substances can easily absorb through the skin.

This way, they would be more effective, she added.

“What is also important is that the materials are clean and safe,” said the winner of the Islamic Educational Scientific and Cultural Organization (ISESCO) for Science and Technology 2014 award, which was held in Rabat, Morocco, in December.

The recognition was based on her active research and excellent performance in the field of chemistry including her far-reaching oil palm research that has contributed to the pharmaceutical and cosmetics industries.

The award was presented by the ISESCO Director General, Dr Abdulaziz Othman Altwaijri as Prof Mahiran took home a certificate, a medal and a cash prize of USD$5,000.

The biennial award has been organised by the Organisation of the Islamic Conference (OIC) since 1979 to foster and strengthen collaboration in the fields of science, education and culture among the OIC members.

According to Mahiran, efforts have been formulated to commercialise the innovation although it may take time.

“At this stage, we have obtained a pre-commercial project from Malaysian Technology Development Corporation (MTDC),” she said.

Professor Mahiran said in pharmaceuticals, an innovation has successfully produced a drugs delivery method to penetrate the ‘blood brain barrier’, especially for diseases that are associated with the brain, such as Alzheimer, Parkinson, epilepsy and meningitis.

“Drugs are normally hard to reach beyond the ‘blood brain barrier’. Thus we created drugs through nanotechnology, and that way we hope they are more effective,” she said.

She added, the innovation has been tested on animals and there were visible positive effects.

Meanwhile, in the agro-chemcial field, Professor Mahiran said, the formulation was made in a nano form to kill weeds and also perform as a cleaning agent to the environment, thus improve the development of the agricultural industry.

“The ingredients in the cosmetic, pharmaceutical and agro-chemical formulations are made through nanotechnology to produce the best for their efficacy, bio-availability in the products and ensure the safety of the consumers” she affirmed.

Professor Dr Mahiran has led 20 research projects in more than 3 decades since 1982, with provisions of grants worth more than RM7 million.

Her series of scientific research have also garnered her numerous awards including the prestigious Archer Daniels Midlands Award from the American Oil Chemists’ Society and the Ram Rais Biotechnology Award at the International Invention and Innovation Exhibition (ITEX) 2004 – UPM.

For anyone curious about ISESCO you can find the website here (with your pick of three languages). There’s also this description in its Wikipedia entry,

Islamic Educational, Scientific and Cultural Organization (ISESCO) was established by the Organisation of the Islamic Cooperation (OIC) in May 1979. ISESCO is one of the largest international Islamic organizations and specializes in the fields of education, science, and culture. Its headquarters are in Rabat, Morocco.

By the way, UNESCO (United Nations Organization for Education, Science and Culture) was founded in 1945.

Art project (autonomous bot purchases illegal goods) seized by Swiss law enforcement

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Having just attended a talk on Robotics and Rehabilitation which included a segment on Robo Ethics, news of an art project where an autonomous bot (robot) is set loose on the darknet to purchase goods (not all of them illegal) was fascinating in itself (it was part of an art exhibition which also displayed the proceeds of the darknet activity). But things got more interesting when the exhibit attracted legal scrutiny in the UK and occasioned legal action in Switzerland.

Here’s more from a Jan. 23, 2015 article by Mike Masnick for Techdirt (Note: A link has been removed),

… some London-based Swiss artists, !Mediengruppe Bitnik [(Carmen Weisskopf and Domagoj Smoljo)], presented an exhibition in Zurich of The Darknet: From Memes to Onionland. Specifically, they had programmed a bot with some Bitcoin to randomly buy $100 worth of things each week via a darknet market, like Silk Road (in this case, it was actually Agora). The artists’ focus was more about the nature of dark markets, and whether or not it makes sense to make them illegal:

The pair see parallels between copyright law and drug laws: “You can enforce laws, but what does that mean for society? Trading is something people have always done without regulation, but today it is regulated,” says ays [sic] Weiskopff.

“There have always been darkmarkets in cities, online or offline. These questions need to be explored. But what systems do we have to explore them in? Post Snowden, space for free-thinking online has become limited, and offline is not a lot better.”

Interestingly the bot got excellent service as Mike Power wrote in his Dec. 5, 2014 review of the show. Power also highlights some of the legal, ethical, and moral implications,

The gallery is next door to a police station, but the artists say they are not afraid of legal repercussions of their bot buying illegal goods.

“We are the legal owner of the drugs [the bot purchased 10 ecstasy pills along with a baseball cap, a pair of sneaker/runners/trainers among other items] – we are responsible for everything the bot does, as we executed the code, says Smoljo. “But our lawyer and the Swiss constitution says art in the public interest is allowed to be free.”

The project also aims to explore the ways that trust is built between anonymous participants in a commercial transaction for possibly illegal goods. Perhaps most surprisingly, not one of the 12 deals the robot has made has ended in a scam.

“The markets copied procedures from Amazon and eBay – their rating and feedback system is so interesting,” adds Smojlo. “With such simple tools you can gain trust. The service level was impressive – we had 12 items and everything arrived.”

“There has been no scam, no rip-off, nothing,” says Weiskopff. “One guy could not deliver a handbag the bot ordered, but he then returned the bitcoins to us.”

The exhibition scheduled from Oct. 18, 2014 – Jan. 11, 2015 enjoyed an uninterrupted run but there were concerns in the UK (from the Power article),

A spokesman for the National Crime Agency, which incorporates the National Cyber Crime Unit, was less philosophical, acknowledging that the question of criminal culpability in the case of a randomised software agent making a purchase of an illegal drug was “very unusual”.

“If the purchase is made in Switzerland, then it’s of course potentially subject to Swiss law, on which we couldn’t comment,” said the NCA. “In the UK, it’s obviously illegal to purchase a prohibited drug (such as ecstasy), but any criminal liability would need to assessed on a case-by-case basis.”

Masnick describes the followup,

Apparently, that [case-by[case] assessment has concluded in this case, because right after the exhibit closed in Switzerland, law enforcement showed up to seize stuff …

!Mediengruppe Bitnik  issued a Jan. 15, 2015 press release (Note: Links have been removed),

«Can a robot, or a piece of software, be jailed if it commits a crime? Where does legal culpability lie if code is criminal by design or default? What if a robot buys drugs, weapons, or hacking equipment and has them sent to you, and police intercept the package?» These are some of the questions Mike Power asked when he reviewed the work «Random Darknet Shopper» in The Guardian. The work was part of the exhibition «The Darknet – From Memes to Onionland. An Exploration» in the Kunst Halle St. Gallen, which closed on Sunday, January 11, 2015. For the duration of the exhibition, !Mediengruppe Bitnik sent a software bot on a shopping spree in the Deepweb. Random Darknet Shopper had a budget of $100 in Bitcoins weekly, which it spent on a randomly chosen item from the deepweb shop Agora. The work and the exhibition received wide attention from the public and the press. The exhibition was well-attended and was discussed in a wide range of local and international press from Saiten to Vice, Arte, Libération, CNN, Forbes. «There’s just one problem», The Washington Post wrote in January about the work, «recently, it bought 10 ecstasy pills».

What does it mean for a society, when there are robots which act autonomously? Who is liable, when a robot breaks the law on its own initiative? These were some of the main questions the work Random Darknet Shopper posed. Global questions, which will now be negotiated locally.

On the morning of January 12, the day after the three-month exhibition was closed, the public prosecutor’s office of St. Gallen seized and sealed our work. It seems, the purpose of the confiscation is to impede an endangerment of third parties through the drugs exhibited by destroying them. This is what we know at present. We believe that the confiscation is an unjustified intervention into freedom of art. We’d also like to thank Kunst Halle St. Gallen for their ongoing support and the wonderful collaboration. Furthermore, we are convinced, that it is an objective of art to shed light on the fringes of society and to pose fundamental contemporary questions.

This project brings to mind Isaac Asimov’s three laws of robotics and a question (from the Wikipedia entry; Note: Links have been removed),

The Three Laws of Robotics (often shortened to The Three Laws or Three Laws, also known as Asimov’s Laws) are a set of rules devised by the science fiction author Isaac Asimov. The rules were introduced in his 1942 short story “Runaround”, although they had been foreshadowed in a few earlier stories. The Three Laws are:

A robot may not injure a human being or, through inaction, allow a human being to come to harm.
A robot must obey the orders given it by human beings, except where such orders would conflict with the First Law.
A robot must protect its own existence as long as such protection does not conflict with the First or Second Law.

Here’s my question, how do you programme a robot to know what would injure a human being? For example, if a human ingests an ecstasy pill the bot purchased, would that be covered in the first law?

Getting back to the robot ethics talk I recently attended, it was given by Ajung Moon (Ph.D. student at the University of British Columbia [Vancouver, Canada] studying Human-Robot Interaction and Roboethics. Mechatronics engineer with a sprinkle of Philosophy background). She has a blog,  Roboethic info DataBase where you can read more on robots and ethics.

I strongly recommend reading both Masnick’s post (he positions this action in a larger context) and Power’s article (more details and images from the exhibit).

A nanoparticle for a medical imaging machine that doesn’t exist yet

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Researchers at the University of Buffalo (New York state) have created a nanoparticle that can be detected by six imaging devices according to a Jan. 20, 2015 news item on ScienceDaily,

It’s technology so advanced that the machine capable of using it doesn’t yet exist.

Using two biocompatible parts, University at Buffalo researchers and their colleagues have designed a nanoparticle that can be detected by six medical imaging techniques:

• computed tomography (CT) scanning;

• positron emission tomography (PET) scanning;

• photoacoustic imaging;

• fluorescence imaging;

• upconversion imaging; and

• Cerenkov luminescence imaging.

The advantages are obvious should somebody, somewhere create a hexamodal (aka, multimodal, aka hypmodal) sensing device capable of exploiting the advantages of this nanoparticle as the researchers hope.

A Jan. 20, 2015 University of Buffalo news release (also on EurekAlert) by Charlotte Hsu, which originated the news item, describes the ideas underlying the research,

This kind of “hypermodal” imaging — if it came to fruition — would give doctors a much clearer picture of patients’ organs and tissues than a single method alone could provide. It could help medical professionals diagnose disease and identify the boundaries of tumors.

“This nanoparticle may open the door for new ‘hypermodal’ imaging systems that allow a lot of new information to be obtained using just one contrast agent,” says researcher Jonathan Lovell, PhD, UB assistant professor of biomedical engineering. “Once such systems are developed, a patient could theoretically go in for one scan with one machine instead of multiple scans with multiple machines.”

When Lovell and colleagues used the nanoparticles to examine the lymph nodes of mice, they found that CT and PET scans provided the deepest tissue penetration, while the photoacoustic imaging showed blood vessel details that the first two techniques missed.

Differences like these mean doctors can get a much clearer picture of what’s happening inside the body by merging the results of multiple modalities.

A machine capable of performing all six imaging techniques at once has not yet been invented, to Lovell’s knowledge, but he and his coauthors hope that discoveries like theirs will spur development of such technology.

The news release also offers a description of the nanoparticles,

The researchers designed the nanoparticles from two components: An “upconversion” core that glows blue when struck by near-infrared light, and an outer fabric of porphyrin-phospholipids (PoP) that wraps around the core.

Each part has unique characteristics that make it ideal for certain types of imaging.

The core, initially designed for upconversion imaging, is made from sodium, ytterbium, fluorine, yttrium and thulium. The ytterbium is dense in electrons — a property that facilitates detection by CT scans.

The PoP wrapper has biophotonic qualities that make it a great match for fluorescence and photoacoustic imagining. The PoP layer also is adept at attracting copper, which is used in PET and Cerenkov luminescence imaging.

“Combining these two biocompatible components into a single nanoparticle could give tomorrow’s doctors a powerful, new tool for medical imaging,” says Prasad, also a SUNY Distinguished Professor of chemistry, physics, medicine and electrical engineering at UB. “More studies would have to be done to determine whether the nanoparticle is safe to use for such purposes, but it does not contain toxic metals such as cadmium that are known to pose potential risks and found in some other nanoparticles.”

“Another advantage of this core/shell imaging contrast agent is that it could enable biomedical imaging at multiple scales, from single-molecule to cell imaging, as well as from vascular and organ imaging to whole-body bioimaging,” Chen adds. “These broad, potential capabilities are due to a plurality of optical, photoacoustic and radionuclide imaging abilities that the agent possesses.”

Lovell says the next step in the research is to explore additional uses for the technology.

For example, it might be possible to attach a targeting molecule to the PoP surface that would enable cancer cells to take up the particles, something that photoacoustic and fluorescence imaging can detect due to the properties of the smart PoP coating. This would enable doctors to better see where tumors begin and end, Lovell says.

The researchers have provided two images,

This transmission electron microscopy image shows the nanoparticles, which consist of a core that glows blue when struck by near-infrared light, and an outer fabric of porphyrin-phospholipids (PoP) that wraps around the core. Credit: Jonathan Lovell

This transmission electron microscopy image shows the nanoparticles, which consist of a core that glows blue when struck by near-infrared light, and an outer fabric of porphyrin-phospholipids (PoP) that wraps around the core.
Credit: Jonathan Lovell

University at Buffalo researchers and colleagues have designed a nanoparticle detectable by six medical imaging techniques. This illustration depicts the particles as they are struck by beams of energy and emit signals that can be detected by the six methods: CT and PET scanning, along with photoacoustic, fluorescence, upconversion and Cerenkov luminescence imaging. Credit: Jonathan Lovell

University at Buffalo researchers and colleagues have designed a nanoparticle detectable by six medical imaging techniques. This illustration depicts the particles as they are struck by beams of energy and emit signals that can be detected by the six methods: CT and PET scanning, along with photoacoustic, fluorescence, upconversion and Cerenkov luminescence imaging.
Credit: Jonathan Lovell

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

Hexamodal Imaging with Porphyrin-Phospholipid-Coated Upconversion Nanoparticles by James Rieffel, Feng Chen, Jeesu Kim, Guanying Chen, Wei Shao, Shuai Shao, Upendra Chitgupi, Reinier Hernandez, Stephen A. Graves, Robert J. Nickles, Paras N. Prasad, Chulhong Kim, Weibo Cai, and Jonathan F. Lovell. Advanced Materials DOI: 10.1002/adma.201404739 Article first published online: 14 JAN 2015

© 2015 WILEY-VCH Verlag GmbH & Co. KGaA, Weinheim

This article is behind a paywall.

The perfect keyboard: it self-cleans and self-powers and it can identify its owner(s)

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There’s a pretty nifty piece of technology being described in a Jan. 21, 2015 news item on Nanowerk, which focuses on the security aspects first (Note: A link has been removed),

In a novel twist in cybersecurity, scientists have developed a self-cleaning, self-powered smart keyboard that can identify computer users by the way they type. The device, reported in the journal ACS Nano (“Personalized Keystroke Dynamics for Self-Powered Human–Machine Interfacing”), could help prevent unauthorized users from gaining direct access to computers.

A Jan. 21, 2015 American Chemical Society (ACS) news release (also on EurekAlert), which originated the news item, continues with the keyboard’s security features before briefly mentioning the keyboard’s self-powering and self-cleaning capabilities,

Zhong Lin Wang and colleagues note that password protection is one of the most common ways we control who can log onto our computers — and see the private information we entrust to them. But as many recent high-profile stories about hacking and fraud have demonstrated, passwords are themselves vulnerable to theft. So Wang’s team set out to find a more secure but still cost-effective and user-friendly approach to safeguarding what’s on our computers.

The researchers developed a smart keyboard that can sense typing patterns — including the pressure applied to keys and speed — that can accurately distinguish one individual user from another. So even if someone knows your password, he or she cannot access your computer because that person types in a different way than you would. It also can harness the energy generated from typing to either power itself or another small device. And the special surface coating repels dirt and grime. The scientists conclude that the keyboard could provide an additional layer of protection to boost the security of our computer systems.

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

Personalized Keystroke Dynamics for Self-Powered Human–Machine Interfacing by Jun Chen, Guang Zhu, Jin Yang, Qingshen Jing, Peng Bai, Weiqing Yang, Xuewei Qi, Yuanjie Su, and Zhong Lin Wang. ACS Nano, Article ASAP DOI: 10.1021/nn506832w Publication Date (Web): December 30, 2014

Copyright © 2014 American Chemical Society

This paper is behind a paywall. I did manage a peek at the paper and found that the keyboard is able to somehow harvest the mechanical energy of typing and turn it into electricity so it can self-power. Self-cleaning is made possible by a nanostructure surface modification. An idle thought and a final comment. First, I wonder what happens if you want to or have to share your keyboard? Second, a Jan. 21, 2015 article about the intelligent keyboard by Luke Dormehl for Fast Company notes that the researchers are from the US and China and names two of the institutions involved in this collaboration, Georgia Institute of Technology and the Beijing Institute of Nanoenergy and Nanosystems,.

ETA Jan. 23, 2015: There’s a Georgia Institute of Technology Jan. 21, 2015 news release on EurekAlert about the intelligent keyboard which offers more technical details such as these,

Conventional keyboards record when a keystroke makes a mechanical contact, indicating the press of a specific key. The intelligent keyboard records each letter touched, but also captures information about the amount of force applied to the key and the length of time between one keystroke and the next. Such typing style is unique to individuals, and so could provide a new biometric for securing computers from unauthorized use.

In addition to providing a small electrical current for registering the key presses, the new keyboard could also generate enough electricity to charge a small portable electronic device or power a transmitter to make the keyboard wireless.

An effect known as contact electrification generates current when the user’s fingertips touch a plastic material on which a layer of electrode material has been coated. Voltage is generated through the triboelectric and electrostatic induction effects. Using the triboelectric effect, a small charge can be produced whenever materials are brought into contact and then moved apart.

“Our skin is dielectric and we have electrostatic charges in our fingers,” Wang noted. “Anything we touch can become charged.”

…

Instead of individual mechanical keys as in traditional keyboards, Wang’s intelligent keyboard is made up of vertically-stacked transparent film materials. Researchers begin with a layer of polyethylene terephthalate between two layers of indium tin oxide (ITO) that form top and bottom electrodes.

Next, a layer of fluorinated ethylene propylene (FEP) is applied onto the ITO surface to serve as an electrification layer that generates triboelectric charges when touched by fingertips. FEP nanowire arrays are formed on the exposed FEP surface through reactive ion etching.

The keyboard’s operation is based on coupling between contact electrification and electrostatic induction, rather than the traditional mechanical switching. When a finger contacts the FEP, charge is transferred at the contact interface, injecting electrons from the skin into the material and creating a positive charge.

When the finger moves away, the negative charges on the FEP side induces positive charges on the top electrode, and equal amounts of negative charges on the bottom electrode. Consecutive keystrokes produce a periodic electrical field that drives reciprocating flows of electrons between the electrodes. Though eventually dissipating, the charges remain on the FEP surface for an extended period of time.

Wang believes the new smart keyboard will be competitive with existing keyboards, in both cost and durability. The new device is based on inexpensive materials that are widely used in the electronics industry.

Atoms can be in two places at once

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A Jan. 20, 2015 news item on Nanowerk offers a brief history of quantum mechanics,

Can a penalty kick simultaneously score a goal and miss? For very small objects, at least, this is possible: according to the predictions of quantum mechanics, microscopic objects can take different paths at the same time. The world of macroscopic objects follows other rules: the football always moves in a definite direction. But is this always correct? Physicists of the University of Bonn have constructed an experiment designed to possibly falsify this thesis. Their first experiment shows that Caesium atoms can indeed take two paths at the same time.

Almost 100 years ago physicists Werner Heisenberg, Max Born und Erwin Schrödinger created a new field of physics: quantum mechanics. Objects of the quantum world – according to quantum theory – no longer move along a single well-defined path. Rather, they can simultaneously take different paths and end up at different places at once.

A Jan. 20, 2015 Universität Bonn (University of Bonn) press release, which originated the news item, describes both the experiment and the thought process which led to the experiment,

At the level of atoms, it looks as if objects indeed obey quantum mechanical laws. Over the years, many experiments have confirmed quantum mechanical predictions. In our macroscopic daily experience, however, we witness a football flying along exactly one path; it never strikes the goal and misses at the same time.

“There are two different interpretations,” says Dr. Andrea Alberti of the Institute of Applied Physics of the University of Bonn. “Quantum mechanics allows superposition states of large, macroscopic objects. But these states are very fragile, even following the football with our eyes is enough to destroy the superposition and makes it follow a definite trajectory.”

But it could also be that footballs obey completely different rules than those applying for single atoms. “Let us talk about the macro-realistic view of the world,” Alberti explains. “According to this interpretation, the ball always moves on a specific trajectory, independent of our observation, and in contrast to the atom.”

In collaboration with Dr. Clive Emary of the University of Hull in the U.K., the Bonn team has come up with an experimental scheme that may help to answer this question. “The challenge was to develop a measurement scheme of the atoms’ positions which allows one to falsify macro-realistic theories,” adds Alberti.

The physicists describe their research in the journal “Physical Review X:” With two optical tweezers they grabbed a single Caesium atom and pulled it in two opposing directions. In the macro-realist’s world the atom would then be at only one of the two final locations. Quantum-mechanically, the atom would instead occupy a superposition of the two positions.

“We have now used indirect measurements to determine the final position of the atom in the most gentle way possible,” says the PhD student Carsten Robens. Even such an indirect measurement (see figure) significantly modified the result of the experiments. This observation excludes – falsifies, as Karl Popper would say more precisely – the possibility that Caesium atoms follow a macro-realistic theory. Instead, the experimental findings of the Bonn team fit well with an interpretation based on superposition states that get destroyed when the indirect measurement occurs. All that we can do is to accept that the atom has indeed taken different paths at the same time.

“This is not yet a proof that quantum mechanics hold for large objects,” cautions Alberti. “The next step is to separate the Caesium atom’s two positions by several millimetres. Should we still find the superposition in our experiment, the macro-realistic theory would suffer another setback.”

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

Ideal negative measurements in quantum walks disprove theories based on classical trajectories by Carsten Robens, Wolfgang Alt, Dieter Meschede, Clive Emary, und Andrea Alberti. Physical Review X, 20.1.2015 (DOI: 10.1103/PhysRevX.5.011003)

This is an open access paper,

Multi-walled carbon nanotubes and blood clotting

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There’s been a lot of interest in using carbon nanotubes (CNTs) for biomedical applications such as drug delivery. New research from Trinity College Dublin (TCD) suggests that multi-walled carbon nanotubes (MWCNTs) may have some limitations when applied to biomedical uses. From a Jan. 20, 2014 news item on Nanowerk (Note: A link has been removed),

Scientists in the School of Pharmacy and Pharmaceutical Sciences in Trinity College Dublin, have made an important discovery about the safety issues of using carbon nanotubes as biomaterials which come into contact with blood. The significance of their findings is reflected in their paper being published as the feature story and front page cover of the international, peer-reviewed journal Nanomedicine (“Blood biocompatibility of surface-bound multi-walled carbon nanotubes”).

A Jan. 19, 2015 TCD press release, which originated the news item, offers a good description of the issues around blood clotting and the research problem (nonfunctionalized CNTs and blood compartibility) the scientists were addressing (Note: Links have been removed),

When blood comes into contact with foreign surfaces the blood’s platelets are activated which in turn leads to blood clots being formed. This can be catastrophic in clinical settings where extracorporeal circulation technologies are used such as during heart-lung bypass, in which the blood is circulated in PVC tubing outside the body. More than one million cardiothoracic surgeries are performed each year and while new circulation surfaces that prevent platelet activation are urgently needed, effective technologies have remained elusive.

One hope has been that carbon nanotubes, which are enormously important as potentially useful biomedical materials, might provide a solution to this challenge and this led the scientists from the School of Pharmacy and Pharmaceutical Sciences in collaboration with Trinity’s School of Chemistry and with colleagues from UCD and the University of Michigan in Ann Arbour to test the blood biocompatibility of carbon nanotubes. They found that the carbon nanotubes did actually stimulate blood platelet activation, subsequently leading to serious and devastating blood clotting. The findings have implications for the design of medical devices which contain nanoparticles and which are used in conjunction with flowing blood.

Speaking about their findings, Professor Marek Radomski, Chair of Pharmacology, Trinity and the paper’s senior author said: “Our results bear significance for the design of blood-facing medical devices, surface-functionalised with nanoparticles or containing surface-shedding nanoparticles. We feel that the risk/benefit ratio with particular attention to blood compatibility should be carefully evaluated during the development of such devices. Furthermore, it is clear that non-functionalised carbon nanotubes both soluble and surface-bound are not blood-compatible”.

The press release also quotes a TCD graduate,

Speaking about the significance of these findings for Nanomedicine research, the paper’s first author Dr Alan Gaffney, a Trinity PhD graduate who is now Assistant Professor of Anaesthesiology in Columbia University Medical Centre, New York said: “When new and exciting technologies with enormous potential benefits for medicine are being studied, there is often a bias towards the publication of positive findings. [emphasis mine] The ultimate successful and safe application of nanotechnology in medicine requires a complete understanding of the negative as well as positive effects so that un-intended side effects can be prevented. Our study is an important contribution to the field of nanomedicine and nanotoxicology research and will help to ensure that nanomaterials that come in contact with blood are thoroughly tested for their interaction with blood platelets before they are used in patients.”

Point well taken Dr. Gaffney. Too often there’s an almost euphoric quality to the nanomedicine discussion where nanoscale treatments are described as if they are perfectly benign in advance of any real testing. For example, I wrote about surgical nanobots being used in a human clinical trial in a Jan. 7, 2015 post which features a video of the researcher ‘selling’ his idea. The enthusiasm is laudable and necessary (researchers work for years trying to develop new treatments) but as Gaffney notes there needs to be some counter-ballast and recognition of the ‘positive bias’ issue.

Getting back to the TCD research, here’s a link to and a citation for the paper (or counter-ballast),

Blood biocompatibility of surface-bound multi-walled carbon nanotubes by Alan M. Gaffney, MD, PhD, Maria J. Santos-Martinez, MD, Amro Satti, Terry C. Major, Kieran J. Wynne, Yurii K. Gun’ko, PhD, Gail M. Annich, Giuliano Elia, Marek W. Radomski, MD. January 2015 Volume 11, Issue 1, Pages 39–46 DOI: http://dx.doi.org/10.1016/j.nano.2014.07.005 Published Online: July 26, 2014

This paper is open access.

Government of Canada’s risk assessment for multi-walled carbon nanotubes

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Lynn Bergeson’s Jan. 15, 2015 post on the Nanotechnology Now website mentions a newly issued Canadian risk assessment for multi-walled carbon nanotubes (MWCNTs),

Canada announced on January 9, 2015, that the New Substances Program has published six new risk assessment summaries for chemicals and polymers, including a summary for multi-wall carbon nanotubes.

… Environment Canada and Health Canada conduct risk assessments on new substances. These assessments include consideration of information on physical and chemical properties, hazards, uses, and exposure to determine whether a substance is or may become harmful to human health or environment as set out in Section 64 of the Canadian Environmental Protection Act, 1999 (CEPA 1999), and, if harm is suspected, to introduce any appropriate or required control measures. …

Here’s more information from the Summary of Risk Assessment Conducted Pursuant to subsection 83(1) of the Canadian Environmental Protection Act, 1999
Significant New Activity No. 17192: Multi-wall carbon nanotubes webpage,

Substance Identity

The substance is a short tangled multi-walled carbon nanotube that can be classified as a nanomaterial. [emphasis mine]

Notified Activities

The substance is proposed to be manufactured in or imported into Canada in quantities greater than 1000 kg/yr for use as an additive in plastics.

Environmental Fate and Behaviour

Based on its physical and chemical properties, if released to the environment, the substance will tend to partition to water, sediment, soil, and ambient air. The substance is expected to be persistent in these compartments because it is a stable inorganic chemical that will not degrade. Based on the limited understanding of uptake by organisms, more data is required to assess the bioaccumulation potential of this substance at the current schedule notification.

Ecological Assessment

Based on the available hazard information on the substance and surrogate data on structurally related nanomaterials, the substance has low to moderate (1-100 mg/L) acute toxicity in aquatic life (fish/daphnia/algae). The predicted no effect concentration was calculated to be less than 1 mg/L using the ErC50 from the most sensitive organism (P. subcapitata), which was used to estimate the environmental risk.

The notified and other potential activities in Canada were assessed to estimate the environmental exposure potential of the substance throughout its life cycle. Environmental exposure from the notified activities was determined through a conservative generic single point-source release blending scenario. The predicted environmental concentration for notified activities is estimated to be 2.1 µg/L.

Based on the current use profile in conjunction with low to moderate ecotoxicity endpoints, the substance is unlikely to cause ecological harm in Canada.

However, based on the current understanding of carbon nanotubes and nanomaterials in general, a change in the use profile of the substance (SNAc No. 17192) may significantly alter the exposure resulting in the substance becoming harmful to the environment.  Consequently, more information is necessary to better characterize potential environmental risks.

Human Health Assessment

Based on the available hazard information on the substance, the substance has a low potential for acute toxicity by the oral, dermal and inhalation routes of exposure (oral and dermal LD50 greater than 2000 mg/kg bw; inhalation LC50 greater than 1.3 mg/m3). It is a severe eye irritant (MAS score = 68), a mild skin irritant (PII = 1.08) and at most a weak sensitizer (because the positive control was tested at a concentration 10X higher than the test substance). It is not an in vitro mutagen (negative in a mammalian cell gene mutation test and in a mammalian chromosome aberration test).  Therefore the substance is unlikely to cause genetic damage.

Hazards related to substances used in the workplace should be classified accordingly under the Workplace Hazardous Materials Information System (WHMIS).

However, based on the available information on structurally related nanomaterials, the substance may cause respiratory toxicity, immunotoxicity, cardiovascular toxicity and carcinogenicity following oral and inhalation exposure.

When used as an additive in plastics, the substance is expected to be manufactured in or imported into Canada encapsulated in a solid polymer matrix. The potential site of exposure to the substance is expected to be within industrial facilities. Therefore, direct exposure of the general population is expected to be low. No significant environmental release is anticipated due to the specialized use under this notification and therefore indirect exposure of the general population from environmental media is also expected to be low. However, if the substance is produced in different forms (e.g. liquid polymer form), applied in different formulations or used in any other potential applications, an increased direct or indirect exposure potential may exist.

Based on the low potential for direct and indirect exposure of the general population under the industrial uses identified in this submission, the substance is not likely to pose a significant health risk to the general population, and is therefore unlikely to be harmful to human health.

However, based on the current understanding of carbon nanotubes and of nanomaterials in general, the risk arising from the use of the substance in consumer products is not known at this time.  The use of the substance in consumer products or in products intended for use by or for children may significantly alter the exposure of the general population resulting in the substance becoming harmful to human health.  Similarly, the import or manufacture of the substance in quantities greater than 10 000 kg/yr may significantly increase the exposure levels of the general population resulting in the substance becoming harmful to human health.  Consequently, more information is necessary to better characterize potential health risks.

I would like to see a definition for the word short as applied, in this risk assessment, to multi-walled carbon nanotubes. That said, this assessment is pretty much in line with current thinking about short, multi-walled carbon nanotubes. In short (wordplay noted), these carbon nanotubes are relatively safe (although some toxicological issues have been noted) as far as can be determined. However, the ‘relatively safe’ assessment may change as more of these carbon nanotubes enter the environment and as people are introduced to more products containing them.

One last comment, I find it surprising I can’t find any mention in the risk assessment of emergency situations such as fire, earthquake, explosions, etc. which could conceivably release short multi-walled carbon nanotubes into the air exposing emergency workers and people caught in a disaster. As well, those airborne materials might subsequently be found in greater quantity in the soil and water.

Brain Talks: Robotics and Rehabilitation at Vancouver (Canada) General Hospital

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The latest Brain Talk will take place tomorrow, Jan. 21, 2015 at 6 pm at Vancouver (Canada) General Hospital. More logistical details follow this description of the talk (from the Robotics and Rehabilitation webpage),

Presenter:  AJung Moon, Nick Snow, and Navid Shirzad

As interactive robots become substantially more accessible to the general public in the near future, one of the main concerns for designers  is in implementing socially acceptable and ethical human-robot interaction for non-expert users.  One approach to addressing this concern is to develop a robot that can take advantage of human moral decision making – much of which are suggested to be based on intuition and strongly connected with the emotional part of the human brain, rather than the rational part of the brain.  In this talk, A. Jung will present the promising, yet cautionary, tales of the moral synergy robots and humans can create.

Speaker details:

  • AJung Moon, PhD Candidate in Mechanical Engineering, Vanier Scholar, CARIS Lab: Robo-Ethics
  • Nick Snow, Masters Candidate in Rehabilitation Sciences, Brain Behaviour Lab: Robo-Wrist Rehabilitation
  • Navid Shirzad, PhD Candidate in Biomedical Engineering, RREACH Lab: Rehabilitation Robotics

Here are the details,

6:00pm-8:00pm, Jan 21, 2015
Paetzold Auditorium, Jim Pattison Pavilion North, 899 West 12th Avenue, Vancouver, BC

…

Free wine and cheese reception to follow

Please RSVP here.

Maybe I’ll see you there, eh?

Biocompatible cellulose sheaths for implants

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Strictly speaking this is not my usual scale which is nano but the topic is of some interest to me so here goes a micro scale story.

It’s well known the body rejects foreign objects no matter how helpful or necessary to our continued existence. A Jan. 19, 2015 news item on Nanowerk describes research into developing more biocompatible implants (Note: A link has been removed),

The human immune system distinguishes between endogenous and foreign bodies. This is highly useful when defending the body against pathogens, but can become a problem if a patient requires an artificial implant like a pacemaker or a heart assist device. In some cases the body responds with an inflammation, and it may even reject the device altogether. Researchers at ETH Zurich [Swiss Federal Institute of Technology] are now introducing a promising method to ameliorate this process –fabricating pre-structured cellulose materials that cover or coat devices with three-dimensional micro-structures and thus make them exceptionally biocompatible (“Surface-Structured Bacterial Cellulose with Guided Assembly-Based Biolithography (GAB)”).

A Jan. 19, 2015 ETH Zurich press written by Angelika Jacobs, which originated the news item, describes the research in more detail,

Researchers had already discovered that cells interact better with rough or structured surfaces than with smooth ones and can cling to them more effectively. However, until now it has not been possible to apply these surface structures to one of the most promising materials in the field of medicine: cellulose produced by bacteria. Bacterial cellulose has received major attention in research in recent years due to the fact that it is durable, adaptable and well tolerated by the human body. For example, practical tests are already being carried out on artificial blood vessels and cartilage made using bacterial cellulose. The versatile material is also an effective option for use as wound dressings.

A research team led by ETH Professor Dimos Poulikakos and Aldo Ferrari at the Laboratory of Thermodynamics in Emerging Technologies, has now succeeded in creating bacterial cellulose with a controlled surface structure. This is produced using a silicon mould with a three-dimensional, optimised geometry (such as a line grid) on a micrometre scale, which is then floated on the surface of a nutrient solution in which the cellulose-producing bacteria grow. The bacteria create a dense network of cellulose strands at the interface between liquid and air. The researchers observed that when the mould was present the bacteria conformed to it, producing a cellulose layer together with a negative replica of the line grid.

Surface structure conveys signals to cells

The line grid also enabled the bacteria to produce an increased number of cellulose strands in approximate alignment with the grid. “In principle, human cells have the ability to identify fibres, such as endogenous collagen, as part of the connective tissue,” explains Aldo Ferrari. The cellulose strands and the grid pattern provide cells with an orientation along predetermined paths that they can sense. “This is of major benefit to wound dressings. Skin cells could grow over a wound more effectively if they moved in accordance with structured cellulose.” The material also has a sort of memory: the structure is even retained when the cellulose is dried for storage purposes and moistened again just before use.

Poulikakos explains that in the production of cellulose surfaces, it is now possible to provide them with a message for the cells that will grow there in the future. “Think of it as a form of Braille.” This enables the right ‘message’ intended for later use to be written on the surface.

Less inflammation due to a structured surface

Such structures serve not only as means of orientation for cells, but also help to minimise the body’s rejection reaction to an artificial implant. In studies using mice, researchers compared smooth and structured cellulose and discovered that the mice with structured cellulose inserted under their skin showed significantly fewer signs of inflammation.

The researchers are now looking to follow up on these initial promising results by testing the material under more complex conditions. They could, for example, structure the cellulose surface of artificial blood vessels in a way that optimises the flow of blood, thereby ensuring that these vessels do not become blocked as easily.

As is often the case these days, there the researchers will be attempting to commercialize this work (from the news release; Note: A link has been removed),

In addition, researchers working with Poulikakos and Ferrari have founded the spin-off Hylomorph to make the method market-ready. “We are planning to apply the structured cellulose as part of the “Zurich Heart” project at the new Wyss Translational Center [founded jointly by ETH Zurich and the University of Zurich; it is not related to the Wyss Institute of Biologically Inspired Engineering at Harvard University],” reveals Poulikakos. The aim of this project is to develop artificial cardiac pump devices that help patients with serious heart problems in the period before a heart donor becomes available – they could even be used as a permanent alternative to a donor heart. Although cardiac pumps are already available, the options that they provide have been limited until now as they are not particularly durable and can cause complications. “Our aim is for artificial implants to be accepted by the patient’s body without inflammation or rejection,” explains Ferrari. As part of the Zurich Heart project, the researchers are, in effect, helping to design the packaging and internal coating for the optimised cardiac pumps. The aim is to minimise the number of complications in the future.

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

Surface-Structured Bacterial Cellulose with Guided Assembly-Based Biolithography (GAB) by Simone Bottan, Francesco Robotti, Prageeth Jayathissa, Alicia Hegglin, Nicolas Bahamonde, José A. Heredia-Guerrero, Ilker S. Bayer, Alice Scarpellini, Hannes Merker, Nicole Lindenblatt, Dimos Poulikakos, and Aldo Ferrari. ACS Nano, Article ASAP DOI: 10.1021/nn5036125
Publication Date (Web): December 19, 2014

Copyright © 2014 American Chemical Society

The paper is behind a paywall.

I can’t find a Hylomorph website or one for the Wyss Translational Center (there is a Dec. 12, 2014 ETH media release announcing its existence).