Monthly Archives: January 2017

Drip dry housing

This piece on new construction materials does have a nanotechnology aspect although it’s not made clear exactly how nanotechnology plays a role.

From a Dec. 28, 2016 news item on phys.org (Note: A link has been removed),

The construction industry is preparing to use textiles from the clothing and footwear industries. Gore-Tex-like membranes, which are usually found in weather-proof jackets and trekking shoes, are now being studied to build breathable, water-resistant walls. Tyvek is one such synthetic textile being used as a “raincoat” for homes.

You can find out more about Tyvek here.on the Dupont website.

A Dec. 21, 2016 press release by Chiara Cecchi for Youris ((European Research Media Center), which originated the news item, proceeds with more about textile-type construction materials,

Camping tents, which have been used for ages to protect against wind, ultra-violet rays and rain, have also inspired the modern construction industry, or “buildtech sector”. This new field of research focuses on the different fibres (animal-based such as wool or silk, plant-based such as linen and cotton and synthetic such as polyester and rayon) in order to develop technical or high-performance materials, thus improving the quality of construction, especially for buildings, dams, bridges, tunnels and roads. This is due to the fibres’ mechanical properties, such as lightness, strength, and also resistance to many factors like creep, deterioration by chemicals and pollutants in the air or rain.

“Textiles play an important role in the modernisation of infrastructure and in sustainable buildings”, explains Andrea Bassi, professor at the Department of Civil and Environmental Engineering (DICA), Politecnico of Milan, “Nylon and fiberglass are mixed with traditional fibres to control thermal and acoustic insulation in walls, façades and roofs. Technological innovation in materials, which includes nanotechnologies [emphasis mine] combined with traditional textiles used in clothes, enables buildings and other constructions to be designed using textiles containing steel polyvinyl chloride (PVC) or ethylene tetrafluoroethylene (ETFE). This gives the materials new antibacterial, antifungal and antimycotic properties in addition to being antistatic, sound-absorbing and water-resistant”.

Rooflys is another example. In this case, coated black woven textiles are placed under the roof to protect roof insulation from mould. These building textiles have also been tested for fire resistance, nail sealability, water and vapour impermeability, wind and UV resistance.

Photo: Production line at the co-operative enterprise CAVAC Biomatériaux, France. Natural fibres processed into a continuous mat (biofib) – Martin Ansell, BRE CICM, University of Bath, UK

In Spain three researchers from the Technical University of Madrid (UPM) have developed a new panel made with textile waste. They claim that it can significantly enhance both the thermal and acoustic conditions of buildings, while reducing greenhouse gas emissions and the energy impact associated with the development of construction materials.

Besides textiles, innovative natural fibre composite materials are a parallel field of the research on insulators that can preserve indoor air quality. These bio-based materials, such as straw and hemp, “can reduce the incidence of mould growth because they breathe. The breathability of materials refers to their ability to absorb and desorb moisture naturally”, says expert Finlay White from Modcell, who contributed to the construction of what they claim are the world’s first commercially available straw houses, “For example, highly insulated buildings with poor ventilation can build-up high levels of moisture in the air. If the moisture meets a cool surface it will condensate and producing mould, unless it is managed. Bio-based materials have the means to absorb moisture so that the risk of condensation is reduced, preventing the potential for mould growth”.

The Bristol-based green technology firm [Modcell] is collaborating with the European Isobio project, which is testing bio-based insulators which perform 20% better than conventional materials. “This would lead to a 5% total energy reduction over the lifecycle of a building”, explains Martin Ansell, from BRE Centre for Innovative Construction Materials (BRE CICM), University of Bath, UK, another partner of the project.

“Costs would also be reduced. We are evaluating the thermal and hygroscopic properties of a range of plant-derived by-products including hemp, jute, rape and straw fibres plus corn cob residues. Advanced sol-gel coatings are being deposited on these fibres to optimise these properties in order to produce highly insulating and breathable construction materials”, Ansell concludes.

You can find Modcell here.

Here’s another image, which I believe is a closeup of the processed fibre shown in the above,

Production line at the co-operative enterprise CAVAC Biomatériaux, France. Natural fibres processed into a continuous mat (biofib) – Martin Ansell, BRE CICM, University of Bath, UK [Note: This caption appears to be a copy of the caption for the previous image]

Preprogramming silk protein-based materials

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A new material based on silk proteins has been developed at Tufts University (US), according to a Dec. 26, 2016 news item on ScienceDaily,

Tufts University engineers have created a new format of solids made from silk protein that can be preprogrammed with biological, chemical, or optical functions, such as mechanical components that change color with strain, deliver drugs, or respond to light, according to a paper published online this week [Dec. 26 -30, 2016] in Proceedings of the National Academy of Sciences (PNAS).

Caption: This image shows examples of engineered 3-D silk constructs. Credit: Silklab, Department of Biomedical Engineering, School of Engineering, Tufts University

A Dec. 26, 2016 Tufts University news release (also on EurekAlert), which originated the news item, describes the research in more detail,

Using a water-based fabrication method based on protein self-assembly, the researchers generated three-dimensional bulk materials out of silk fibroin, the protein that gives silk its durability. Then they manipulated the bulk materials with water-soluble molecules to create multiple solid forms, from the nano- to the micro-scale, that have embedded, pre-designed functions.

For example, the researchers created a surgical pin that changes color as it nears its mechanical limits and is about to fail, functional screws that can be heated on demand in response to infrared light, and a biocompatible component that enables the sustained release of bioactive agents, such as enzymes.

Although more research is needed, additional applications could include new mechanical components for orthopedics that can be embedded with growth factors or enzymes, a surgical screw that changes color as it reaches its torque limits, hardware such as nuts and bolts that sense and report on the environmental conditions of their surroundings, or household goods that can be remolded or reshaped.

Silk’s unique crystalline structure makes it one of nature’s toughest materials. Fibroin, an insoluble protein found in silk, has a remarkable ability to protect other materials while being fully biocompatible and biodegradable.

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

Programming function into mechanical forms by directed assembly of silk bulk materials by Benedetto Marelli, Nereus Patel, Thomas Duggan, Giovanni Perotto, Elijah Shirman, Chunmei Li, David L. Kaplan, and Fiorenzo G. Omenetto. PNAS 10.1073/pnas.1612063114 December 27, 2016

This paper is behind a paywall.

Bionic pancreas tested at home

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This news about a bionic pancreas must be exciting for diabetics as it would eliminate the need for constant blood sugar testing throughout the day. From a Dec. 19, 2016 Massachusetts General Hospital news release (also on EurekAlert), Note: Links have been removed,

The bionic pancreas system developed by Boston University (BU) investigators proved better than either conventional or sensor-augmented insulin pump therapy at managing blood sugar levels in patients with type 1 diabetes living at home, with no restrictions, over 11 days. The report of a clinical trial led by a Massachusetts General Hospital (MGH) physician is receiving advance online publication in The Lancet.

“For study participants living at home without limitations on their activity and diet, the bionic pancreas successfully reduced average blood glucose, while at the same time decreasing the risk of hypoglycemia,” says Steven Russell, MD, PhD, of the MGH Diabetes Unit. “This system requires no information other than the patient’s body weight to start, so it will require much less time and effort by health care providers to initiate treatment. And since no carbohydrate counting is required, it significantly reduces the burden on patients associated with diabetes management.”

Developed by Edward Damiano, PhD, and Firas El-Khatib, PhD, of the BU Department of Biomedical Engineering, the bionic pancreas controls patients’ blood sugar with both insulin and glucagon, a hormone that increases glucose levels. After a 2010 clinical trial confirmed that the original version of the device could maintain near-normal blood sugar levels for more than 24 hours in adult patients, two follow-up trials – reported in a 2014 New England Journal of Medicine paper – showed that an updated version of the system successfully controlled blood sugar levels in adults and adolescents for five days. Another follow-up trial published in The Lancet Diabetes and Endocrinology in 2016 showed it could do the same for children as young as 6 years of age.

While minimal restrictions were placed on participants in the 2014 trials, participants in both spent nights in controlled settings and were accompanied at all times by either a nurse for the adult trial or remained in a diabetes camp for the adolescent and pre-adolescent trials. Participants in the current trial had no such restrictions placed upon them, as they were able to pursue normal activities at home or at work with no imposed limitations on diet or exercise. Patients needed to live within a 30-minute drive of one of the trial sites – MGH, the University of Massachusetts Medical School, Stanford University, and the University of North Carolina at Chapel Hill – and needed to designate a contact person who lived with them and could be contacted by study staff, if necessary.

The bionic pancreas system – the same as that used in the 2014 studies – consisted of a smartphone (iPhone 4S) that could wirelessly communicate with two pumps delivering either insulin or glucagon. Every five minutes the smartphone received a reading from an attached continuous glucose monitor, which was used to calculate and administer a dose of either insulin or glucagon. The algorighms controlling the system were updated for the current trial to better respond to blood sugar variations.

While the device allows participants to enter information about each upcoming meal into a smartphone app, allowing the system to deliver an anticipatory insulin dose, such entries were optional in the current trial. If participants’ blood sugar dropped to dangerous levels or if the monitor or one of the pumps was disconnected for more than 15 minutes, the system would alerted study staff, allowing them to check with the participants or their contact persons.

Study participants were adults who had been diagnosed with type 1 diabetes for a year or more and had used an insulin pump to manage their care for at least six months. Each of 39 participants that finished the study completed two 11-day study periods, one using the bionic pancreas and one using their usual insulin pump and any continous glucose monitor they had been using. In addition to the automated monitoring of glucose levels and administered doses of insulin or glucagon, participants completed daily surveys regarding any episodes of symptomatic hypoglycemia, carbohydrates consumed to treat those episodes, and any episodes of nausea.

On days when participants were on the bionic pancreas, their average blood glucose levels were significantly lower – 141 mg/dl versus 162 mg/dl – than when on their standard treatment. Blood sugar levels were at levels indicating hypoglycemia (less than 60 mg/dl) for 0.6 percent of the time when participants were on the bionic pancreas, versus 1.9 percent of the time on standard treatment. Participants reported fewer episodes of symptomatic hypoglycemia while on the bionic pancreas, and no episodes of severe hypoglycemia were associated with the system.

The system performed even better during the overnight period, when the risk of hypoglycemia is particularly concerning. “Patients with type 1 diabetes worry about developing hypoglycemia when they are sleeping and tend to let their blood sugar run high at night to reduce that risk,” explains Russell, an assistant professor of Medicine at Harvard Medical School. “Our study showed that the bionic pancreas reduced the risk of overnight hypoglycemia to almost nothing without raising the average glucose level. In fact the improvement in average overnight glucose was greater than the improvement in average glucose over the full 24-hour period.”

Damiano, whose work on this project is inspired by his own 17-year-old son’s type 1 diabetes, adds, “The availability of the bionic pancreas would dramatically change the life of people with diabetes by reducing average glucose levels – thereby reducing the risk of diabetes complications – reducing the risk of hypoglycemia, which is a constant fear of patients and their families, and reducing the emotional burden of managing type 1 diabetes.” A co-author of the Lancet report, Damiano is a professor of Biomedical Engineering at Boston University.

The BU patents covering the bionic pancreas have been licensed to Beta Bionics, a startup company co-founded by Damiano and El-Khatib. The company’s latest version of the bionic pancreas, called the iLet, integrates all components into a single unit, which will be tested in future clinical trials. People interested in participating in upcoming trials may contact Russell’s team at the MGH Diabetes Research Center in care of Llazar Cuko (LCUKO@mgh.harvard.edu ).

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

Home use of a bihormonal bionic pancreas versus insulin pump therapy in adults with type 1 diabetes: a multicentre randomised crossover trial by Firas H El-Khatib, Courtney Balliro, Mallory A Hillard, Kendra L Magyar, Laya Ekhlaspour, Manasi Sinha, Debbie Mondesir, Aryan Esmaeili, Celia Hartigan, Michael J Thompson, Samir Malkani, J Paul Lock, David M Harlan, Paula Clinton, Eliana Frank, Darrell M Wilson, Daniel DeSalvo, Lisa Norlander, Trang Ly, Bruce A Buckingham, Jamie Diner, Milana Dezube, Laura A Young, April Goley, M Sue Kirkman, John B Buse, Hui Zheng, Rajendranath R Selagamsetty, Edward R Damiano, Steven J Russell. Lancet DOI: http://dx.doi.org/10.1016/S0140-6736(16)32567-3 Published: 19 December 2016

This paper is behind a paywall.

You can find out more about Beta Bionics and iLet here.

Saving modern art with 3D-printed artwork

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I first wrote about the NanoRestART project in an April 4. 2016 post highlighting work which focuses on a problem unique to modern and contemporary art, the rapid deterioration of the plastics and synthetic materials used to create the art and the lack of conservation techniques for preserving those materials. A Dec. 22, 2016 news item on phys.org provides an update on the project,

Many contemporary artworks are endangered due to their extremely fast degradation processes. NANORESTART—a project developing nanomaterials to protect and restore this cultural heritage—has created a 3-D printed artwork with a view to testing restoration methods.

The 3D printed sculpture was designed by engineer-artist Tom Lomax – a UK-based sculptor and painter specialised in 3D-printed colour sculpture. Drawing inspiration from the aesthetic of early 20th century artworks, the sculpture was made using state-of-the-art 3D printing processes and can be downloaded for free. [I believe the downloadable files are available at the end of the paper in Heritage Science in the section titled: Additional files, just prior to the References {see below for citation and link to the paper}

Fig. 1
Images of the RP artwork “Out of the Cauldron” designed by Tom Lomax produced with the most common RP Technologies: (1) stereolithography (SLA®) (2) polyjet (3) 3D printing (3DP) (4) selective laser sintering (SLS). Before (above) and after (below) photodegradation
Courtesy: Heritage Science

A Dec. 21, 2016 Cordis press release, which originated the news item, provides more information about the artist and his 3D printed sculpture,

‘As an artist I previously had little idea of the conservation threat facing contemporary art – preferring to leave these issues for conservators and focus on the creative process. But while working on this project with UCL [University College of London] I began to realise that artists themselves have a crucial role to play,’ Lomax explains.

The structure has been printed using the most common rapid prototyping (RP) technologies, which are gaining popularity among designers and artists. It will be a key tool for the project team to test how these structures degrade and come up with solutions to better preserve them.

As Caroline Coon, researcher at the UCL Institute for Sustainable Heritage, notes, ‘Art is being transformed by fast-changing new technologies and it is therefore vital to preempt conservation issues, rather than react to them, if we are to preserve our best contemporary works for future generations. This research project will benefit both artists and academics alike – but ultimately it is in the best interests of the public that art and science combine to preserve works.’

The NANORESTART team subjected the artwork to accelerated testing, discovering that many 3D-printing technologies use materials that degrade particularly rapidly. It is particularly true for polymers, whose only-recently achieved cultural heritage status also means that conservation experience is almost inexistent.

Preserving or not: an intricate question for artists

The experiments were part of a UCL paper entitled ‘Preserving Rapid Prototypes: A Review’, published in late November in Heritage Science. In this review, Caroline Coon and her team have critically assessed the most commonly used technologies used to tackle the degradation of materials, noting that ‘to conserve RP artworks it is necessary to have an understanding of the process of creation, the different technologies involved, the materials used as well as their chemical and mechanical properties.’

Besides technical concerns, the paper also voices those of artists, in particular the importance of the original artefact and the debate around the appropriateness of preventing the degradation process of artworks. Whilst digital conservation of these artworks would prevent degradation and allow designs to be printed on-demand, some artists argue that the original artefact is actually the one with artistic value as it references a specific time and place. On the other hand, some artists actually embrace and accept the natural degradation of their art as part of its charm.

With two more years to go before its completion, NANORESTART will undoubtedly bring valuable results, resources and reflexions to both conservators and artists. The nanomaterials it aims to develop will bring the EU at the forefront of a conservation market estimated at some EUR 5 billion per year.

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

Preserving rapid prototypes: a review by Carolien Coon, Boris Pretzel, Tom Lomax, and Matija Strlič. Heritage Science 2016 4:40 DOI: 10.1186/s40494-016-0097-y Published: 22 November 2016

© The Author(s) 2016

This paper is open access.

Spintronics-based artificial intelligence

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Courtesy: Tohoku University

Japanese researchers have managed to mimic a synapse (artificial neural network) with a spintronics-based device according to a Dec. 19, 2016 Tohoku University press release (also on EurekAlert but dated Dec. 20, 2016),

Researchers at Tohoku University have, for the first time, successfully demonstrated the basic operation of spintronics-based artificial intelligence.

Artificial intelligence, which emulates the information processing function of the brain that can quickly execute complex and complicated tasks such as image recognition and weather prediction, has attracted growing attention and has already been partly put to practical use.

The currently-used artificial intelligence works on the conventional framework of semiconductor-based integrated circuit technology. However, this lacks the compactness and low-power feature of the human brain. To overcome this challenge, the implementation of a single solid-state device that plays the role of a synapse is highly promising.

The Tohoku University research group of Professor Hideo Ohno, Professor Shigeo Sato, Professor Yoshihiko Horio, Associate Professor Shunsuke Fukami and Assistant Professor Hisanao Akima developed an artificial neural network in which their recently-developed spintronic devices, comprising micro-scale magnetic material, are employed (Fig. 1). The used spintronic device is capable of memorizing arbitral values between 0 and 1 in an analogue manner unlike the conventional magnetic devices, and thus perform the learning function, which is served by synapses in the brain.

Using the developed network (Fig. 2), the researchers examined an associative memory operation, which is not readily executed by conventional computers. Through the multiple trials, they confirmed that the spintronic devices have a learning ability with which the developed artificial neural network can successfully associate memorized patterns (Fig. 3) from their input noisy versions just like the human brain can.

The proof-of-concept demonstration in this research is expected to open new horizons in artificial intelligence technology – one which is of a compact size, and which simultaneously achieves fast-processing capabilities and ultralow-power consumption. These features should enable the artificial intelligence to be used in a broad range of societal applications such as image/voice recognition, wearable terminals, sensor networks and nursing-care robots.

Here are Fig. 1 and Fig. 2, as mentioned in the press release,

Fig. 1. (a) Optical photograph of a fabricated spintronic device that serves as artificial synapse in the present demonstration. Measurement circuit for the resistance switching is also shown. (b) Measured relation between the resistance of the device and applied current, showing analogue-like resistance variation. (c) Photograph of spintronic device array mounted on a ceramic package, which is used for the developed artificial neural network. Courtesy: Tohoku University

Fig. 2. Block diagram of developed artificial neural network, consisting of PC, FPGA, and array of spintronics (spin-orbit torque; SOT) devices. Courtesy: Tohoku University

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

Analogue spin–orbit torque device for artificial-neural-network-based associative memory operation by William A. Borders, Hisanao Akima1, Shunsuke Fukami, Satoshi Moriya, Shouta Kurihara, Yoshihiko Horio, Shigeo Sato, and Hideo Ohno. Applied Physics Express, Volume 10, Number 1 https://doi.org/10.7567/APEX.10.013007. Published 20 December 2016

© 2017 The Japan Society of Applied Physics

This is an open access paper.

For anyone interested in my other posts on memristors, artificial brains, and artificial intelligence, you can search this blog for those terms and/or Neuromorphic Engineering in the Categories section.

Sniffing out disease (Na-Nose)

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The ‘artificial nose’ is not a newcomer to this blog. The most recent post prior to this is a March 15, 2016 piece about Disney using an artificial nose for art conservation. Today’s (Jan. 9, 2016) piece concerns itself with work from Israel and ‘sniffing out’ disease, according to a Dec. 30, 2016 news item in Sputnik News,

A team from the Israel Institute of Technology has developed a device that from a single breath can identify diseases such as multiple forms of cancer, Parkinson’s disease, and multiple sclerosis. While the machine is still in the experimental stages, it has a high degree of promise for use in non-invasive diagnoses of serious illnesses.

The international team demonstrated that a medical theory first proposed by the Greek physician Hippocrates some 2400 years ago is true, certain diseases leave a “breathprint” on the exhalations of those afflicted. The researchers created a prototype for a machine that can pick up on those diseases using the outgoing breath of a patient. The machine, called the Na-Nose, tests breath samples for the presence of trace amounts of chemicals that are indicative of 17 different illnesses.

A Dec. 22, 2016 Technion Israel Institute of Technology press release offers more detail about the work,

An international team of 56 researchers in five countries has confirmed a hypothesis first proposed by the ancient Greeks – that different diseases are characterized by different “chemical signatures” identifiable in breath samples. …

Diagnostic techniques based on breath samples have been demonstrated in the past, but until now, there has not been scientific proof of the hypothesis that different and unrelated diseases are characterized by distinct chemical breath signatures. And technologies developed to date for this type of diagnosis have been limited to detecting a small number of clinical disorders, without differentiation between unrelated diseases.

The study of more than 1,400 patients included 17 different and unrelated diseases: lung cancer, colorectal cancer, head and neck cancer, ovarian cancer, bladder cancer, prostate cancer, kidney cancer, stomach cancer, Crohn’s disease, ulcerative colitis, irritable bowel syndrome, Parkinson’s disease (two types), multiple sclerosis, pulmonary hypertension, preeclampsia and chronic kidney disease. Samples were collected between January 2011 and June 2014 from in 14 departments at 9 medical centers in 5 countries: Israel, France, the USA, Latvia and China.

The researchers tested the chemical composition of the breath samples using an accepted analytical method (mass spectrometry), which enabled accurate quantitative detection of the chemical compounds they contained. 13 chemical components were identified, in different compositions, in all 17 of the diseases.

According to Prof. Haick, “each of these diseases is characterized by a unique fingerprint, meaning a different composition of these 13 chemical components. Just as each of us has a unique fingerprint that distinguishes us from others, each disease has a chemical signature that distinguishes it from other diseases and from a normal state of health. These odor signatures are what enables us to identify the diseases using the technology that we developed.”

With a new technology called “artificially intelligent nanoarray,” developed by Prof. Haick, the researchers were able to corroborate the clinical efficacy of the diagnostic technology. The array enables fast and inexpensive diagnosis and classification of diseases, based on “smelling” the patient’s breath, and using artificial intelligence to analyze the data obtained from the sensors. Some of the sensors are based on layers of gold nanoscale particles and others contain a random network of carbon nanotubes coated with an organic layer for sensing and identification purposes.

The study also assessed the efficiency of the artificially intelligent nanoarray in detecting and classifying various diseases using breath signatures. To verify the reliability of the system, the team also examined the effect of various factors (such as gender, age, smoking habits and geographic location) on the sample composition, and found their effect to be negligible, and without impairment on the array’s sensitivity.

“Each of the sensors responds to a wide range of exhalation components,” explain Prof. Haick and his previous Ph.D student, Dr. Morad Nakhleh, “and integration of the information provides detailed data about the unique breath signatures characteristic of the various diseases. Our system has detected and classified various diseases with an average accuracy of 86%.

This is a new and promising direction for diagnosis and classification of diseases, which is characterized not only by considerable accuracy but also by low cost, low electricity consumption, miniaturization, comfort and the possibility of repeating the test easily.”

“Breath is an excellent raw material for diagnosis,” said Prof. Haick. “It is available without the need for invasive and unpleasant procedures, it’s not dangerous, and you can sample it again and again if necessary.”

Here’s a schematic of the study, which the researchers have made available,

Diagram: A schematic view of the study. Two breath samples were taken from each subject, one was sent for chemical mapping using mass spectrometry, and the other was analyzed in the new system, which produced a clinical diagnosis based on the chemical fingerprint of the breath sample. Courtesy: Tech;nion

There is also a video, which covers much of the same ground as the press release but also includes information about the possible use of the Na-Nose technology in the European Union’s SniffPhone project,

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

Diagnosis and Classification of 17 Diseases from 1404 Subjects via Pattern Analysis of Exhaled Molecules by Morad K. Nakhleh, Haitham Amal, Raneen Jeries, Yoav Y. Broza, Manal Aboud, Alaa Gharra, Hodaya Ivgi, Salam Khatib, Shifaa Badarneh, Lior Har-Shai, Lea Glass-Marmor, Izabella Lejbkowicz, Ariel Miller, Samih Badarny, Raz Winer, John Finberg, Sylvia Cohen-Kaminsky, Frédéric Perros, David Montani, Barbara Girerd, Gilles Garcia, Gérald Simonneau, Farid Nakhoul, Shira Baram, Raed Salim, Marwan Hakim, Maayan Gruber, Ohad Ronen, Tal Marshak, Ilana Doweck, Ofer Nativ, Zaher Bahouth, Da-you Shi, Wei Zhang, Qing-ling Hua, Yue-yin Pan, Li Tao, Hu Liu, Amir Karban, Eduard Koifman, Tova Rainis, Roberts Skapars, Armands Sivins, Guntis Ancans, Inta Liepniece-Karele, Ilze Kikuste, Ieva Lasina, Ivars Tolmanis, Douglas Johnson, Stuart Z. Millstone, Jennifer Fulton, John W. Wells, Larry H. Wilf, Marc Humbert, Marcis Leja, Nir Peled, and Hossam Haick. ACS Nano, Article ASAP DOI: 10.1021/acsnano.6b04930 Publication Date (Web): December 21, 2016

Copyright © 2017 American Chemical Society

This paper appears to be open access.

As for SniffPhone, they’re hoping that Na-Nose or something like it will allow them to modify smartphones in a way that will allow diseases to be detected.

I can’t help wondering who will own the data if your smartphone detects a disease. If you think that’s an idle question, here’s an excerpt from Sue Halpern’s Dec. 22, 2016 review of two books (“Weapons of Math Destruction: How Big Data Increases Inequality and Threatens Democracy” by Cathy O’Neil and “Virtual Competition: The Promise and Perils of the Algorithm-Driven Economy” by Ariel Ezrachi and Maurice E. Stucke) for the New York Times Review of Books,

We give our data away. We give it away in drips and drops, not thinking that data brokers will collect it and sell it, let alone that it will be used against us. There are now private, unregulated DNA databases culled, in part, from DNA samples people supply to genealogical websites in pursuit of their ancestry. These samples are available online to be compared with crime scene DNA without a warrant or court order. (Police are also amassing their own DNA databases by swabbing cheeks during routine stops.) In the estimation of the Electronic Frontier Foundation, this will make it more likely that people will be implicated in crimes they did not commit.

Or consider the data from fitness trackers, like Fitbit. As reported in The Intercept:

During a 2013 FTC panel on “Connected Health and Fitness,” University of Colorado law professor Scott Peppet said, “I can paint an incredibly detailed and rich picture of who you are based on your Fitbit data,” adding, “That data is so high quality that I can do things like price insurance premiums or I could probably evaluate your credit score incredibly accurately.”

Halpern’s piece is well worth reading in its entirety.

Changes to the US 21st Century Nanotechnology Research and Development Act

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This is one of Barack Obama’s last acts as President of the US according to a Jan. 5, 2017 posting by Lynn L. Bergeson on the Nanotechnology Now website,

The American Innovation and Competitiveness Act (S. 3084) would amend the 21st Century Nanotechnology Research and Development Act (15 U.S.C. § 7501 et seq.) to change the frequency of National Nanotechnology Initiative (NNI) reports. The strategic plan would be released every five instead of every three years, and the triennial review would be renamed the quadrennial review and be prepared every four years instead of every three. The evaluation of the NNI, which is submitted to Congress, would be due every four instead of every three years. … On December 28, 2016, the bill was presented to President Obama. President Obama is expected to sign the bill.

Congress.gov is hosting the S.3084 – American Innovation and Competitiveness Act webpage listing all of the actions, to date, taken on behalf of this bill; Obama signed the act on Jan. 6, 2017.

One final note, Obama’s last day as US President is Friday, Jan. 20, 2016 but his last ‘full’ day is Thursday, Jan. 19, 2016 (according to a Nov. 4, 2016 posting by Tom Muse for About.com).

Nanoparticle ‘caterpillars’ and immune system ‘crows’

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This University of Colorado work fits in nicely with other efforts to ensure that nanoparticle medical delivery systems get to their destinations. From a Dec. 19, 2016 news item on phys.org,

In the lab, doctors can attach chemotherapy to nanoparticles that target tumors, and can use nanoparticles to enhance imaging with MRI, PET and CT scans. Unfortunately, nanoparticles look a lot like pathogens – introducing nanoparticles to the human body can lead to immune system activation in which, at best, nanoparticles are cleared before accomplishing their purpose, and at worst, the onset of dangerous allergic reaction. A University of Colorado Cancer Center paper published today [Dec. 19, 2016] in the journal Nature Nanotechnology details how the immune system recognizes nanoparticles, potentially paving the way to counteract or avoid this detection.

Specifically, the study worked with dextran-coated iron oxide nanoparticles, a promising and versatile class of particles used as drug-delivery vehicles and MRI contrast enhancers in many studies. As their name implies, the particles are tiny flecks of iron oxide encrusted with sugar chains.

“We used several sophisticated microscopy approaches to understand that the particles basically look like caterpillars,” says Dmitri Simberg, PhD, investigator at the CU Cancer Center and assistant professor in the Skaggs School of Pharmacy and Pharmaceutical Sciences, the paper’s senior author.

The comparison is striking: the iron oxide particle is the caterpillar’s body, which is surrounded by fine hairs of dextran.

Caption: University of Colorado Cancer Study shows how nanoparticles activate the complement system, potentially paving the way for expanded use of these technologies.
Credit: University of Colorado Cancer Center

A Dec. 19, 2016 University of Colorado news release on EurekAlert, which originated the news item, describes the work in more detail,

If Simberg’s dextran-coated iron oxide nanoparticles are caterpillars, then the immune system is a fat crow that would eat them – that is, if it can find them. In fact, the immune system has evolved for exactly this purpose – to find and “eat” foreign particles – and rather than one homogenous entity is actually composed of a handful of interrelated systems, each specialized to counteract a specific form of invading particle.

Simberg’s previous work shows that it is the immune subcomponent called the complement system that most challenges nanoparticles. Basically, the complement system is a group of just over 30 proteins that circulate through the blood and attach to invading particles and pathogens. In humans, complement system activation requires that three proteins come together on a particle -C3b, Bb and properdin – which form a stable complex called C3-convertase.

“The whole complement system activation starts with the assembly of C3-convertase,” Simberg says. “In this paper, we ask the question of how the complement proteins actually recognize the nanoparticle surface. How is this whole reaction triggered?”

First, it was clear that the dextran coating that was supposed to protect the nanoparticles from human complement attack was not doing its job. Simberg and colleagues could see complement proteins literally invade the barrier of dextran hairs.

“Electron microscopy images show protein getting inside the particle to touch the iron oxide core,” Simberg says.

In fact, as long as the nanoparticle coating allowed the nanoparticle to absorb proteins from blood, the C3 convertase was assembled and activated on these proteins. The composition of the coating was irrelevant – if any blood protein was able to bind to nanoparticles, it always led to complement activation. Moreover, Simberg and colleagues also showed that complement system activation is a dynamic and ongoing process – blood proteins and C3 convertase constantly dissociate from nanoparticles, and new proteins and C3 convertases bind to the particles, continuing the cascade of immune system activation. The group also demonstrated that this dynamic assembly of complement proteins occurs not only in the test tubes but also in living organisms as particles circulate in blood.

Simberg suggests that the work points to challenges and three possible strategies to avoid complement system activation by nanoparticles: “First, we could try to change the nanoparticle coating so that it can’t absorb proteins, which is a difficult task; second, we could better understand the composition of proteins absorbed from blood on the particle surface that allow it to bind complement proteins; and third, there are natural inhibitors of complement activation – for example blood Factor H – but in the context of nanoparticles, it’s not strong enough to stop complement activation. Perhaps we could get nanoparticles to attract more Factor H to decrease this activation.”

At one point, the concept of nanomedicine seemed as if it would be simple – engineers and chemists would make a nanoparticle with affinity for tumor tissue and then attach a drug molecule to it. Or they would inject nanoparticles into patients that would improve the resolution of diagnostic imaging. When the realities associated with the use of nanoparticles in the landscape of the human immune system proved more challenging, many researchers realized the need to step back from possible clinical use to better understand the mechanisms that challenge nanoparticle use.

“This basic groundwork is absolutely necessary,” says Seyed Moein Moghimi, PhD, nanotechnologist at Durham University, UK, and the coauthor of the Simberg paper. “It’s essential that we learn to control the process of immune recognition so that we can bridge between the promise that nanoparticles demonstrate in the lab and their use with real patients in the real world.”

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

Complement proteins bind to nanoparticle protein corona and undergo dynamic exchange in vivo by Fangfang Chen, Guankui Wang, James I. Griffin, Barbara Brenneman, Nirmal K. Banda, V. Michael Holers, Donald S. Backos, LinPing Wu, Seyed Moein Moghimi, & Dmitri Simberg. Nature Nanotechnology (2016) doi:10.1038/nnano.2016.269 19 December 2016

This paper is behind a paywall.

I have a few previous postings about nanoparticles as drug delivery systems which have yet to fulfill their promise. There’s the April 27, 2016 posting (How many nanoparticle-based drugs does it take to kill a cancer tumour? More than 1%) and the Sept. 9, 2016 posting (Discovering how the liver prevents nanoparticles from reaching cancer cells).

Using melanin in bioelectronic devices

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Brazilian researchers are working with melanin to make biosensors and other bioelectronic devices according to a Dec. 20, 2016 news item on phys.org,

Bioelectronics, sometimes called the next medical frontier, is a research field that combines electronics and biology to develop miniaturized implantable devices capable of altering and controlling electrical signals in the human body. Large corporations are increasingly interested: a joint venture in the field has recently been announced by Alphabet, Google’s parent company, and pharmaceutical giant GlaxoSmithKline (GSK).

One of the challenges that scientists face in developing bioelectronic devices is identifying and finding ways to use materials that conduct not only electrons but also ions, as most communication and other processes in the human organism use ionic biosignals (e.g., neurotransmitters). In addition, the materials must be biocompatible.

Resolving this challenge is one of the motivations for researchers at São Paulo State University’s School of Sciences (FC-UNESP) at Bauru in Brazil. They have succeeded in developing a novel route to more rapidly synthesize and to enable the use of melanin, a polymeric compound that pigments the skin, eyes and hair of mammals and is considered one of the most promising materials for use in miniaturized implantable devices such as biosensors.

A Dec. 14, 2016 FAPESP (São Paulo Research Foundation) press release, which originated the news item, further describes both the research and a recent meeting where the research was shared (Note: A link has been removed),

Some of the group’s research findings were presented at FAPESP Week Montevideo during a round-table session on materials science and engineering.

The symposium was organized by the Montevideo Group Association of Universities (AUGM), Uruguay’s University of the Republic (UdelaR) and FAPESP and took place on November 17-18 at UdelaR’s campus in Montevideo. Its purpose was to strengthen existing collaborations and establish new partnerships among South American scientists in a range of knowledge areas. Researchers and leaders of institutions in Uruguay, Brazil, Argentina, Chile and Paraguay attended the meeting.

“All the materials that have been tested to date for applications in bioelectronics are entirely synthetic,” said Carlos Frederico de Oliveira Graeff, a professor at UNESP Bauru and principal investigator for the project, in an interview given to Agência FAPESP.

“One of the great advantages of melanin is that it’s a totally natural compound and biocompatible with the human body: hence its potential use in electronic devices that interface with brain neurons, for example.”

Application challenges

According to Graeff, the challenges of using melanin as a material for the development of bioelectronic devices include the fact that like other carbon-based materials, such as graphene, melanin is not easily dispersible in an aqueous medium, a characteristic that hinders its application in thin-film production.

Furthermore, the conventional process for synthesizing melanin is complex: several steps are hard to control, it can last up to 56 days, and it can result in disorderly structures.

In a series of studies performed in recent years at the Center for Research and Development of Functional Materials (CDFM), where Graeff is a leading researcher and which is one of the Research, Innovation and Dissemination Centers (RIDCs) funded by FAPESP, he and his collaborators managed to obtain biosynthetic melanin with good dispersion in water and a strong resemblance to natural melanin using a novel synthesis route.

The process developed by the group at CDMF takes only a few hours and is based on changes in parameters such as temperature and the application of oxygen pressure to promote oxidation of the material.

By applying oxygen pressure, the researchers were able to increase the density of carboxyl groups, which are organic functional groups consisting of a carbon atom double bonded to an oxygen atom and single bonded to a hydroxyl group (oxygen + hydrogen). This enhances solubility and facilitates the suspension of biosynthetic melanin in water.

“The production of thin films of melanin with high homogeneity and quality is made far easier by these characteristics,” Graeff said.

By increasing the density of carboxyl groups, the researchers were also able to make biosynthetic melanin more similar to the biological compound.

In living organisms, an enzyme that participates in the synthesis of melanin facilitates the production of carboxylic acids. The new melanin synthesis route enabled the researchers to mimic the role of this enzyme chemically while increasing carboxyl group density.

“We’ve succeeded in obtaining a material that’s very close to biological melanin by chemical synthesis and in producing high-quality film for use in bioelectronic devices,” Graeff said.

Through collaboration with colleagues at research institutions in Canada [emphasis mine], the Brazilian researchers have begun using the material in a series of applications, including electrical contacts, pH sensors and photovoltaic cells.

More recently, they have embarked on an attempt to develop a transistor, a semiconductor device used to amplify or switch electronic signals and electrical power.

“Above all, we aim to produce transistors precisely in order to enhance this coupling of electronics with biological systems,” Graeff said.

I’m glad to have gotten some information about the work in South America. It’s one of FrogHeart’s shortcomings that I have so little about the research in that area of the world. I believe this is largely due to my lack of Spanish language skills. Perhaps one day there’ll be a universal translator that works well. In the meantime, it was a surprise to see Canada mentioned in this piece. I wonder which Canadian research institutions are involved with this research in South America.

Science as a post-truth concept

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The word of 2016, according to the Oxford Dictionary of English, is ‘post-truth’ and Steve Fuller, a professor from the University of Warwick (UK), has written an intriguing Dec. 15, 2016 essay for the Guardian tracing the origins of post-truth as it relates to the sciences (Note: Links have been removed),

Even today, more than fifty years after its first edition, Thomas Kuhn’s The Structure of Scientific Revolutions remains the first port of call to learn about the history, philosophy or sociology of science. This is the book famous for talking about science as governed by ‘paradigms’ until overtaken by ‘revolutions’.

Kuhn argued that the way that both scientists and the general public need to understand the history of science is Orwellian. He is alluding to 1984, in which the protagonist’s job is to rewrite newspapers from the past to make it seem as though the government’s current policy is where it had been heading all along. In this perpetually airbrushed version of history, the public never sees the U-turns, switches of allegiance and errors of judgement that might cause them to question the state’s progressive narrative. Confidence in the status quo is maintained and new recruits are inspired to follow in its lead. Kuhn claimed that what applies to totalitarian 1984 also applies to science united under the spell of a paradigm.
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What makes Kuhn’s account of science ‘post-truth’ is that truth is no longer the arbiter of legitimate power but rather the mask of legitimacy that is worn by everyone in pursuit of power. Truth is just one more – albeit perhaps the most important – resource in a power game without end. In this respect, science differs from politics only in that the masks of its players rarely drop.

The explanation for what happens behind the masks lies in the work of the Italian political economist Vilfredo Pareto (1848-1923), devotee of Machiavelli, admired by Mussolini and one of sociology’s forgotten founders. Kuhn spent his formative years at Harvard in the late 1930s when the local kingmaker, biochemist Lawrence Henderson, not only taught the first history of science courses but also convened an interdisciplinary ‘Pareto Circle’ to get the university’s rising stars acquainted with the person he regarded as Marx’s only true rival.

For Pareto, what passes for social order is the result of the interplay of two sorts of elites, which he called, following Machiavelli, ‘lions’ and ‘foxes’. The lions acquire legitimacy from tradition, which in science is based on expertise rather than lineage or custom. Yet, like these earlier forms of legitimacy, expertise derives its authority from the cumulative weight of intergenerational experience. This is exactly what Kuhn meant by a ‘paradigm’ in science – a set of conventions by which knowledge builds in an orderly fashion to complete a certain world-view established by a founding figure – say, Newton or Darwin. Each new piece of knowledge is anointed by a process of ‘peer review’.
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As in 1984, the lions normally dictate the historical narrative. But on the cutting room floor lies the activities of the other set of elites, the foxes. In today’s politics of science, they are known by a variety of names, ranging from ‘mavericks’ to ‘social constructivists’ to ‘pseudoscientists’. Foxes are characterised by dissent and unrest, thriving in a world of openness and opportunity.

Foxes stress the present as an ecstatic moment in which there is everything to play for. This includes a decisive break with ‘the past’, which they know has been fictionalized anyway, as in 1984. Self-styled visionaries present themselves, like Galileo, as the first to see what is in plain sight. Expertise appears as a repository of corrupt judgement designed to suppress promising alternatives to already bankrupt positions. For Kuhn, the scientific foxes get the upper hand whenever cracks appear in the lions’ smooth narrative, the persistent ‘anomalies’ that can’t be explained by the ruling paradigm.

But the foxes have their own Achilles Heel: They are strong in opposition but divisively self-critical in office. …

I encourage you to read the essay in its entirety although I don’t necessarily subscribe to the some of the statements. For example, I wouldn’t lump ‘mavericks’, ‘social constructivists’, and ‘pseudoscientists’ together without some discussion about ‘pseudoscience’. It’s true that an accusation of ‘pseudoscience’ is often leveled at people who are challenging the status quo but there are also situations where people use science as a mask to legitimate some fairly hinky work.