Tag Archives: Wales

How small can a carbon nanotube get before it stops being ‘electrical’?

Research, which began as an attempt to get reproducible electronics (?) measurements, yielded some unexpected results according ta January 3, 2018 news item on phys.org,

Carbon nanotubes bound for electronics not only need to be as clean as possible to maximize their utility in next-generation nanoscale devices, but contact effects may limit how small a nano device can be, according to researchers at the Energy Safety Research Institute (ESRI) at Swansea University [UK] in collaboration with researchers at Rice University [US].

ESRI Director Andrew Barron, also a professor at Rice University in the USA, and his team have figured out how to get nanotubes clean enough to obtain reproducible electronic measurements and in the process not only explained why the electrical properties of nanotubes have historically been so difficult to measure consistently, but have shown that there may be a limit to how “nano” future electronic devices can be using carbon nanotubes.

Swansea University Issued a January 3, 2018 press release (also on EurekAlert), which originated the news item, explains the work in more detail,

Like any normal wire, semiconducting nanotubes are progressively more resistant to current along their length. But conductivity measurements of nanotubes over the years have been anything but consistent. The ESRI team wanted to know why.

“We are interested in the creation of nanotube based conductors, and while people have been able to make wires their conduction has not met expectations. We were interested in determining the basic sconce behind the variability observed by other researchers.”

They discovered that hard-to-remove contaminants — leftover iron catalyst, carbon and water — could easily skew the results of conductivity tests. Burning them away, Barron said, creates new possibilities for carbon nanotubes in nanoscale electronics.

The new study appears in the American Chemical Society journal Nano Letters.

The researchers first made multiwalled carbon nanotubes between 40 and 200 nanometers in diameter and up to 30 microns long. They then either heated the nanotubes in a vacuum or bombarded them with argon ions to clean their surfaces.

They tested individual nanotubes the same way one would test any electrical conductor: By touching them with two probes to see how much current passes through the material from one tip to the other. In this case, their tungsten probes were attached to a scanning tunneling microscope.

In clean nanotubes, resistance got progressively stronger as the distance increased, as it should. But the results were skewed when the probes encountered surface contaminants, which increased the electric field strength at the tip. And when measurements were taken within 4 microns of each other, regions of depleted conductivity caused by contaminants overlapped, further scrambling the results.

“We think this is why there’s such inconsistency in the literature,” Barron said.

“If nanotubes are to be the next generation lightweight conductor, then consistent results, batch-to-batch, and sample-to-sample, is needed for devices such as motors and generators as well as power systems.”

Annealing the nanotubes in a vacuum above 200 degrees Celsius (392 degrees Fahrenheit) reduced surface contamination, but not enough to eliminate inconsistent results, they found. Argon ion bombardment also cleaned the tubes, but led to an increase in defects that degrade conductivity.

Ultimately they discovered vacuum annealing nanotubes at 500 degrees Celsius (932 Fahrenheit) reduced contamination enough to accurately measure resistance, they reported.

To now, Barron said, engineers who use nanotube fibers or films in devices modify the material through doping or other means to get the conductive properties they require. But if the source nanotubes are sufficiently decontaminated, they should be able to get the right conductivity by simply putting their contacts in the right spot.

“A key result of our work was that if contacts on a nanotube are less than 1 micron apart, the electronic properties of the nanotube changes from conductor to semiconductor, due to the presence of overlapping depletion zones” said Barron, “this has a potential limiting factor on the size of nanotube based electronic devices – this would limit the application of Moore’s law to nanotube devices.”

Chris Barnett of Swansea is lead author of the paper. Co-authors are Cathren Gowenlock and Kathryn Welsby, and Rice alumnus Alvin Orbaek White of Swansea. Barron is the Sêr Cymru Chair of Low Carbon Energy and Environment at Swansea and the Charles W. Duncan Jr.–Welch Professor of Chemistry and a professor of materials science and nanoengineering at Rice.

The Welsh Government Sêr Cymru National Research Network in Advanced Engineering and Materials, the Sêr Cymru Chair Program, the Office of Naval Research and the Robert A. Welch Foundation supported the research.

Rice University has published a January 4, 2018 Rice University news release (also on EurekAlert), which is almost (95%) identical to the press release from Swansea. That’s a bit unusual as collaborating institutions usually like to focus on their unique contributions to the research, hence, multiple news/press releases.

Dexter Johnson, in a January 11, 2018 post on his Nanoclast blog (on the IEEE [Institute of Electrical and Electronics Engineers] website,  adds a detail or two while writing in an accessible style.

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

Spatial and Contamination-Dependent Electrical Properties of Carbon Nanotubes by Chris J. Barnett, Cathren E. Gowenlock, Kathryn Welsby, Alvin Orbaek White, and Andrew R. Barron. Nano Lett., Article ASAP DOI: 10.1021/acs.nanolett.7b03390 Publication Date (Web): December 19, 2017

Copyright © 2017 American Chemical Society

This paper is behind a paywall.

Carbon nanotubes for enhanced wheat growth?

It’s been a long time (Oct. 22, 2009 posting; scroll down about 20% of the way) since I’ve written about carbon nanotubes and their possible use in agriculture but now a December 6, 2017 news item on ScienceDaily raises the topic again,

The introduction of purified carbon nanotubes appears to have a beneficial effect on the early growth of wheatgrass, according to Rice University scientists. But in the presence of contaminants, those same nanotubes could do great harm.

The Rice lab of chemist Andrew Barron grew wheatgrass in a hydroponic garden to test the potential toxicity of nanoparticles on the plant. To their surprise, they found one type of particle dispersed in water helped the plant grow bigger and faster.

They suspect the results spring from nanotubes’ natural hydrophobic (water-avoiding) nature that in one experiment apparently facilitated the plants’ enhanced uptake of water.

The research appears in the Royal Society of Chemistry journal Environmental Science: Nano.

A December 6, 2017 Rice University news release (also on EurekAlert), which originated the news item, expands on the theme,

The lab mounted the small-scale study with the knowledge that the industrial production of nanotubes will inevitably lead to their wider dispersal in the environment. The study cited rapid growth in the market for nanoparticles in drugs, cosmetic, fabrics, water filters and military weapons, with thousands of tons produced annually.

Despite their widespread use, Barron said few researchers have looked at the impact of environmental nanoparticles — whether natural or man-made — on plant growth.

The researchers planted wheatgrass seeds in multiple replicates in cotton wool and fed them with dispersions that contained raw single-walled or multi-walled nanotubes, purified single-walled nanotubes or iron oxide nanoparticles that mimicked leftover catalyst often attached to nanotubes. The solutions were either water or tetrahydrofuran (THF), an industrial solvent. Some of the seeds were fed pure water or THF as a control.

Rice University researchers tested the effects of carbon nanotubes on the growth of wheatgrass. While some showed no effect, purified single-walled nanotubes in water (5) enhanced the plants' growth, while the same nanotubes in a solvent (6) retarded their development. The photos at left show the plants after four days and at right after eight days, with odd-numbered plants growing in water and evens in a solvent. Numbers 1 and 2 are controls without nanotubes; 3-4 contain raw single-walled tubes; 5-6 purified single-walled tubes; 7-8 raw multi-walled tubes; 9-10 low-concentration iron-oxide nanoparticles and 11-12 high-concentration iron-oxide nanoparticles.

Rice University researchers tested the effects of carbon nanotubes on the growth of wheatgrass. While some showed no effect, purified single-walled nanotubes in water (5) enhanced the plants’ growth, while the same nanotubes in a solvent (6) retarded their development. The photos at left show the plants after four days and at right after eight days, with odd-numbered plants growing in water and evens in a solvent. Numbers 1 and 2 are controls without nanotubes; 3-4 contain raw single-walled tubes; 5-6 purified single-walled tubes; 7-8 raw multi-walled tubes; 9-10 low-concentration iron-oxide nanoparticles and 11-12 high-concentration iron-oxide nanoparticles. Click on the image for a larger version. Photos by Seung Mook Lee

After eight days, the plantings showed that purified single-walled nanotubes in water enhanced the germination rate and shoot growth of wheatgrass, which grew an average of 13 percent larger than plants in plain water. Raw single- and multi-walled nanotubes and particles in either solution had little effect on the plants’ growth, they found.

However, purified single-walled nanotubes in THF retarded plant development by 45 percent compared to single-walled nanotubes in water, suggesting the nanotubes act as a carrier for the toxic substance.

The concern, Barron said, is that if single-walled nanotubes combine with organic pollutants like pesticides, industrial chemicals or solvents in the environment, they may concentrate and immobilize the toxins and enhance their uptake by plants.

Nothing seen in the limited study indicated whether carbon nanotubes in the environment, and potentially in plants, will rise up the food chain and be harmful to humans, he said.

On the other hand, the researchers said it may be worth looking at whether hydrophobic substrates that mimic the positive effects observed in single-walled nanotubes could be used for high-efficiency channeling of water to seeds.

“Our work confirms the importance of thinking of nanomaterials as part of a system rather in isolation,” Barron said. “It is the combination with other compounds that is important to understand.”

Seung Mook Lee, a former visiting student research assistant from Memorial High School in Houston and now an undergraduate student at the University of California, Berkeley, is lead author of the paper. Co-authors are Rice research scientist Pavan Raja and graduate student Gibran Esquenazi. Barron is the Charles W. Duncan Jr.–Welch Professor of Chemistry and a professor of materials science and nanoengineering at Rice and the Sêr Cymru Chair of Low Carbon Energy and Environment at Swansea University, Wales (UK).

The Welsh Government Sêr Cymru Program and the Robert A. Welch Foundation supported the research.

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

Effect of raw and purified carbon nanotubes and iron oxide nanoparticles on the growth of wheatgrass prepared from the cotyledons of common wheat (triticum aestivum) by Seung Mook Lee, Pavan M. V. Raja, Gibran L. Esquenazi, and Andrew R. Barron. Environ. Sci.: Nano, 2018, Advance Article DOI: 10.1039/C7EN00680B First published on 09 Nov 2017

This paper appears to be behind a paywall.

Crackpot or visionary? Teaching seven-year-olds about intellectual property

It’s been a while since I’ve devoted a posting to intellectual property issues and my focus is usually on science/technology and how intellectual property issues relate to those fields. As a writer, I support a more relaxed approach to copyright and patent law and, in particular, I want to see the continuation of ‘fair use’ as it’s called in the US and ‘fair dealing’ as it’s called in Canada. I support the principle of making money from your work so you can continue to contribute creatively. But, the application of intellectual property law seems to have been turned into a weapon against creativity of all sorts. (At the end of this post you’ll find links to three typical posts from the many I have written on this topic.)

I do take the point being made in the following video (but for seven-year-olds and up!!!) about trademarks/logos and trademark infringement from the UK’s Intellectual Property Office,

Here’s the description from Youtube’s Logo Mania webpage,

Published on Jan 16, 2018

Brian Wheeler’s January 17, 2018 article for BBC (British Broadcasting Corporation) online news on UK Politics sheds a bit of light on this ‘campaign’ (Note: A link has been removed),

A campaign to teach children about copyright infringement on the internet, is employing cartoons and puns on pop stars’ names, to get the message across.

Even its makers admit it is a “dry” and “niche” subject for a cartoon aimed at seven-year-olds.

But the Intellectual Property Office adds learning to “respect” copyrights and trademarks is a “key life skill”.

And it is hoping the adventures of Nancy and the Meerkats can finally make intellectual property “fun”.

The series, which began life five years ago on Fun Kids Radio, was re-launched this week with the aim of getting its message into primary schools.

The Intellectual Property Office is leading the government’s efforts to crack down on internet piracy and protect the revenues of Britain’s creative industries.

The government agency is spending £20,000 of its own money on the latest Nancy campaign, which is part-funded by the UK music industry.

Catherine Davies, head of the IPO’s education outreach department, which already produces teaching materials for GCSE students, admitted IP was a “complex subject” for small children and something of a challenge to make accessible and entertaining.

Wheeler’s article is definitely worth reading in its entirety. In fact, I was so intrigued I chased down the government press release (from the www.gov.uk webpage),

Nancy and the Meerkats logo

Nancy and the Meerkats, with the help of Big Joe, present a new radio series to engage pupils with the concept of intellectual property (IP). Aimed at primary education, the resource guides pupils through the process of setting up a band and recording and releasing a song, which is promoted and performed live on tour.

Building on the success of the previous two series, Nancy and the Meerkats consists of a new radio series, short videos, comic book, lesson plans and competition. The supporting teaching resource also includes themed activities and engaging lesson plans. Together, these support and develop pupils’ understanding of copyright, trade marks and the importance of respecting IP.

Curriculum links are provided for England, Northern Ireland, Scotland and Wales.

The series will launch on Monday 15th January [2018] at 5pm on Fun Kids Radio

Along with ‘Logo Mania’, you can find such gems as ‘Track Attack’ concerning song lyrics and, presumably, copyright issues, ‘The Hum Bone’ concerning patents, and ‘Pirates on the Internet’ about illegal downloading on the Fun Kids Radio website. Previous seasons have included ‘Are forks just for eating with?’, ‘Is a kaleidoscope useful?’, ‘Rubber Bands’, ‘Cornish Pasties’, and more. It seems Fun Kids Radio has moved from its focus on the types of questions and topics that might interest children to topics of interest for the music industry and the UK’s Intellectual Property Office. At a guess, I’m guessing those groups might be maximalists where copyright is concerned.

By the way, for those interested in teaching resources and more, go to http://crackingideas.com/third_party/Nancy+and+the+Meerkats.

Finally, I’m not sure whether to laugh or cry. I do know that I’m curious about how they decided to focus on seven to 11-year-olds. Are children in the UK heavily involved in content piracy? Is there a generation of grade school pop stars about to enter the music market? Where is the data and how did they gather it?

Should anyone be inclined to answer those questions, I look forward to reading your reply in the Comments section.

ETA January 19, 2018 (five minutes later) Oops! Here are the links promised earlier,

October 31, 2011: Patents as weapons and obstacles

June 28, 2012: Billions lost to patent trolls; US White House asks for comments on intellectual property (IP) enforcement; and more on IP

March 28, 2013: Intellectual property, innovation, and hindrances

There are many, many more posts. Just click on the category for ‘intellectual property’.

Discovering why nanoscale gold has catalytic properties

Gold’s glitter may have inspired poets and triggered wars, but its catalytic prowess has helped make chemical reactions greener and more efficient. (Image courtesy of iStock/sbayram) [downloaded from http://www1.lehigh.edu/news/scientists-uncover-secret-gold%E2%80%99s-catalytic-powers

Gold’s glitter may have inspired poets and triggered wars, but its catalytic prowess has helped make chemical reactions greener and more efficient. (Image courtesy of iStock/sbayram) [downloaded from http://www1.lehigh.edu/news/scientists-uncover-secret-gold%E2%80%99s-catalytic-powers

A Sept. 27, 2016 news item on phys.org describes a discovery made by scientists at Lehigh University (US),

Settling a decades-long debate, new research conclusively shows that a hierarchy of active species exists in gold on iron oxide catalysis designed for low temperature carbon monoxide oxidation; Nanoparticles, sub-nanometer clusters and dispersed atoms—as well as how the material is prepared—are all important for determining catalytic activity.

A Sept. 27, 2016 Lehigh University news release by Lori Friedman, which originated the news item, provides more information about the discovery that gold nanoparticles can be used in catalysis and about the discovery of why that’s possible,

Christopher J. Kiely calls the 1982 discovery by Masatake Haruta that gold (Au) possessed a high level of catalytic activity for carbon monoxide (CO) oxidation when deposited on a metal-oxide “a remarkable turn of events in nanotechnology”—remarkable because gold had long been assumed to be inert for catalysis.

Haruta showed that gold dispersed on iron oxide effectively catalyzed the conversion of harmful carbon monoxide into more benign carbon dioxide (CO2) at room temperatures—a reaction that is critical for the construction of fire fighters’ breathing masks and for removal of CO from hydrogen feeds for fuel cells. In fact, today gold catalysts are being exploited in a major way for the greening of many important reactions in the chemical industry, because they can lead to cleaner, more efficient reactions with fewer by-products.

Haruta and Graham J. Hutchings, who co-discovered the use of gold as a catalyst for different reactions, are noted as Thompson Reuters Citation Laureates and appear annually on the ScienceWatch Nobel Prize prediction list. Their pioneering work opened up a new area of scientific inquiry and kicked off a decades-long debate about which type of supported gold species are most effective for the CO oxidation reaction.

In 2008, using electron microscopy technology that was not yet available in the 1980s and ’90 s, Hutchings, the director of the Cardiff Catalysis Institute at Cardiff University worked with Kiely, the Harold B. Chambers Senior Professor Materials Science and Engineering at Lehigh, examined the structure of supported gold at the nanoscale. One nanometer (nm) is equal to one one-billionth of a meter or about the diameter of five atoms.

Using what was then a rare piece of equipment—Lehigh’s aberration-corrected JEOL 2200 FS scanning transmission electron microscope (STEM)—the team identified the co-existence of three distinct gold species: facetted nanoparticles larger than one nanometer in size, sub-clusters containing less than 20 atoms and individual gold atoms strewn over the support. Because only the larger gold nanoparticles had previously been detected, this created debate as to which of these species were responsible for the good catalytic behavior.

Haruta, professor of applied chemistry at Tokyo Metropolitan University, Hutchings and Kiely have been working collaboratively on this problem over recent years and are now the first to demonstrate conclusively that it is not the particles or the individual atoms or the clusters which are solely responsible for the catalysis—but that they all contribute to different degrees. Their results have been published in an article in Nature Communications titled: “Population and hierarchy of active species in gold iron oxide catalysts for carbon monoxide oxidation.”

“All of the species tend to co-exist in conventionally prepared catalysts and show some level of activity,” says Kiely. “They all do something—but some less efficiently than others.”

Their research revealed the sub-nanometer clusters and 1-3nm nanoparticles to be the most efficient for catalyzing this CO oxidation reaction, while larger particles were less so and the atoms even less.  Nevertheless, Kiely cautions, all the species present need to be considered to fully explain the overall measured activity of the catalyst.

Among the team’s other key findings: the measured activity of gold on iron oxide catalysts is exquisitely dependent on exactly how the material is prepared. Very small changes in synthesis parameters  influence the relative proportion and spatial distribution of these various Au species on the support material and thus have a big impact on its overall catalytic performance.

A golden opportunity

Building on their earlier work (published in a 2008 Science article), the team sought to find a robust way to quantitatively analyze the relative population distributions of nanoparticles of various sizes, sub-nm clusters and highly dispersed atoms in a given gold on iron oxide sample. By correlating this information with catalytic performance measurements, they then hoped to determine which species distribution would be optimal to produce the most efficient catalyst, in order to utilize the precious gold component in the most cost effective way.

Ultimately, it was a catalyst synthesis problem the team faced that offered them a golden opportunity to do just that.

During the collaboration, Haruta’s and Hutchings’ teams each prepared gold on iron oxide samples in their home labs in Tokyo and Cardiff. Even though both groups nominally utilized the same ‘co-precipitation’ synthesis method, it turned out that a final heat treatment step was beneficial to the catalytic performance for one set of materials but detrimental to the other. This observation provided a fascinating scientific conundrum that detailed electron microscopy studies performed by Qian He, one of Kiely’s PhD students at the time, was key to solving. Qian He is now a University Research Fellow at Cardiff University leading their electron microscopy effort.

“In the end, there were subtle differences in the order and speed in which each group added in their ingredients while preparing the material,” explains He. “When examined under the electron microscope, it was clear that the two slightly different methods produced quite different distributions of particles, clusters and dispersed atoms on the support.”

“Very small variations in the preparation route or thermal history of the sample can alter the relative balance of supported gold nanoparticles-to-clusters-to-atoms in the material and this manifests itself in the measured catalytic activity,” adds Kiely.

The group was able to compare this set of materials and correlate the Au species distributions with catalytic performance measurements, ultimately identifying the species distribution that was associated with greater catalytic efficiency.

Now that the team has identified the catalytic activity hierarchy associated with these supported gold species, the next step, says Kiely, will be to modify the synthesis method to positively influence that distribution to optimize the catalyst performance while making the most efficient use of the precious gold metal content.

“As a next stage to this study we would like to be able to observe gold on iron oxide materials in-situ within the electron microscope while the reaction is happening,” says Kiely.

Once again, it is next generation microscopy facilities that may hold the key to fulfilling gold’s promise as a pivotal player in green technology.

Despite the link to the paper already in the news release, here’s one that includes a citation,

Identification of Active Gold Nanoclusters on Iron Oxide Supports for CO Oxidation by Andrew A. Herzing, Christopher J. Kiely, Albert F. Carley, Philip Landon, Graham J. Hutchings. Science  05 Sep 2008: Vol. 321, Issue 5894, pp. 1331-1335 DOI: 10.1126/science.1159639

This paper is currently behind a paywall but, if you can wait one year, free access can be gained if you register (for free) with Science.

A new lens (made from nanobeads) for seeing subwavelength images at visible frequencies

The image which illustrates the research is quite intriguing but I don’t think it makes much sense until you read about the research. From an Aug. 12, 2016 news item on ScienceDaily,

Nanobeads are all around us- and are, some might argue, used too frequently in everything from sun-screen to white paint, but a new ground-breaking application is revealing hidden worlds.

A paper in Science Advances provides proof of a new concept, using new solid 3D superlenses to break through the scale of things previously visible through a microscope.

Illustrating the strength of the new superlens, the scientists describe seeing for the first time, the actual information on the surface of a Blue Ray DVD. That shiny surface is not as smooth as we think. Current microscopes cannot see the grooves containing the data- but now even the data itself is revealed.

Now the image,

(a) Conceptual drawing of nanoparticle-based metamaterial solid immersion lens (mSIL) (b) Lab made mSIL (c) SEM image of 60 nm sized imaging sample (d) corresponding superlens imaging of the 60 nm samples by the developed mSIL. Courtesy: Bangor University

(a) Conceptual drawing of nanoparticle-based metamaterial solid immersion lens (mSIL) (b) Lab made mSIL (c) SEM image of 60 nm sized imaging sample (d) corresponding superlens imaging of the 60 nm samples by the developed mSIL. Credit: ©BangorUniversity Fudan University

An Aug. 13, 2016 Bangor University press release (also on EurekAlert with an Aug. 12, 2016 publication date), which originated the news item, describes the work in more detail,

Led by Dr Zengbo Wang at Bangor University UK and Prof Limin Wu at Fudan University, China, the team created minute droplet-like lens structures on the surface to be examined. These act as an additional lens to magnify the surface features previously invisible to a normal lens.

Made of millions of nanobeads, the spheres break up the light beam. Each bead refracts the light, acting as individual torch-like minute beam. It is the very small size of each beam of light which illuminate the surface, extending the resolving ability of the microscope to record-breaking levels. The new superlens adds 5x magnification on top of existing microscopes.

Extending the limit of classical microscope’s resolution has been the ‘El Dorado’ or ‘Holy Grail’ of microscopy for over a century. Physical laws of light make it impossible to view objects smaller than 200 nm – the smallest size of bacteria, using a normal microscope alone. However, superlenses have been the new goal since the turn of the millennium, with various labs and teams researching different models and materials.

“We’ve used high-index titanium dioxide (TiO2) nanoparticles as the building element of the lens. These nanoparticles are able to bend light to a higher degree than water. To explain, when putting a spoon into a cup of this material, if it were possible, you’d see a larger bend where you spoon enters the material than you would looking at the same spoon in a glass of water,” Dr Wang says.

Nanoparticles splitting single incident beam into multiple=Nanoparticles splitting single incident beam into multiple beams which provides optical super-resolution in imaging.“Each sphere bends the light to a high magnitude and splits the light beam, creating millions of individual beams of light. It is these tiny light beams which enable us to view previously unseen detail.”

Wang believes that the results will be easily replicable and that other labs will soon be adopting the technology and using it for themselves.

The advantages of the technology is that the material, titanium dioxide, is cheap and readily available, and rather than buying a new microscope, the lenses are applied to the material to be viewed, rather than to the microscope.

“We have already viewed details to a far greater level than was previously possible. The next challenge is to adapt the technology for use in biology and medicine. This would not require the current use of a combination of dyes and stains and laser light- which change the samples being viewed. The new lens will be used to see germs and viruses not previously visible.”

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

Three-dimensional all-dielectric metamaterial solid immersion lens for subwavelength imaging at visible frequencies by Wen Fan, Bing Yan, Zengbo Wang, and Limin Wu. Science Advances  12 Aug 2016: Vol. 2, no. 8, e1600901 DOI: 10.1126/sciadv.1600901

This paper is open access.

More about the Antikythera (an ancient computer)

Since 2004, an international consortium has been attempting to decode the mechanism known as an Antikythera. Discovered at the beginning of the 20th century, it has puzzled and intrigued scientists ever since. Last mentioned here in an Oct. 2, 2012 posting, this update is based on a July 20, 2016 essay by Mike Edmunds for The Conversation website. First, here’s a brief overview (Note: A link has been removed),

When we talk of the history of computers, most of us will refer to the evolution of the modern digital desktop PC, charting the decades-long developments by the likes of Apple and Microsoft. What many don’t consider, however, is that computers have been around much longer. In fact, they date back millennia, to a time when they were analogue creations.

Today, the world’s oldest known “computer” is the Antikythera mechanism, a severely corroded bronze artefact which was found at the beginning of the 20th Century, in the remains of a shipwreck near the Mediterranean island of Antikythera. It wasn’t until the 1970s that the importance of the Antikythera mechanism was discovered, when radiography revealed that the device is in fact a complex mechanism of at least 30 gear wheels.

The mechanism has since been established as the first known astronomical calendar, a complex system which can track and predict the cycles of the solar system. Technically, it is a sophisticated mechanical “calculator” rather than a true “computer”, since it cannot be reprogrammed, but nonetheless an impressive artefact.

Edmunds is an emeritus professor at the University of Cardiff (Wales) and the lead academic on the Antikythera Mechanism Research Project.

He describes the mechanism as it is presently understood and includes the latest findings (Note: Links have been removed),

When first made, the mechanism was about the size of a shoe box, with dials on both its front and back faces. A handle or knob on the side of the box enabled the user to turn the trains of gears inside –- originally there were considerably more gears than the 30 that still survive. On the front, pointers showed where the sun and moon were in the sky, and there was a display of the phase of the moon. On the rear, dials displayed a 19-year cycle of lunar months, the 18.2 year Saros cycle of lunar and solar eclipses, and even a four-year cycle of athletic competitions including the Olympic games.

The inscriptions are thought to have been a description for the user of what it was they were viewing as they operated the mechanism. However, the newly published texts add more to what we know of the mechanism: they establish that the positions of the five planets known in antiquity were also shown – Mercury, Venus, Mars, Jupiter and Saturn.

The planets were displayed on the machine in a way that took account of their rather irregular “wanderings” about the sky. Such a display had been suspected, and the confirmation reinforces that this was a very sophisticated and quite complicated device. The actual gear trains needed for the display of the planets are missing – presumably lost in the shipwreck – but we know from the very ingenious way that the sun and moon drives are designed and constructed that the makers of the mechanism certainly had the skills necessary to make the planetary drive.

The newly uncovered inscriptions include passages about what stars were just becoming visible –- or about to be lost in the glare of the sun – at different times of year. The style of these passages is very close to that of a well-known astronomical text by Greek astronomer and mathematician Geminos from the first Century BC. Not only does this tie in perfectly with the presumed date of the shipwreck (around 60BC), but also the latitude – which is implied by stellar data to be mid-Mediterranean – which would fit nicely with the mechanism originating on the island of Rhodes, from where there is a contemporary historic record from the writer Cicero of such devices.

Apparently divers have returned to the site this year to see if they can find more parts to the Antikythera and , hopefully unlock more of its secrets. (h/t July 20, 2016 phys.org news item),

Nanoparticles for infections delivered via hair follicles and Syrian refugee scientists are being welcomed

Hair follicles, nanoparticles, and infections

This first story does mention a Syrian researcher in a subtle fashion which suggests that immigrants (and I imagine refugees too) are welcome as they can be a huge boost to a country, in this case, the UK.

A Dec. 15, 2015 news item on ScienceDaily announces some research focused on using hair follicles to deliver nanoparticles carrying medication,

Many surgery patients develop infections and are a major source of prolonged illness and significant cause of death. Now, a research project is investigating the use of nanoparticles as a way to disinfect wounds. It could prove to be much more effective than existing techniques because the particles would be tiny enough to enter the skin via hair follicles, ensuring much better penetration of the area affected by surgery.

Here’s a close up of some hairy skin,

Courtesy: University Huddersfield

Courtesy: University Huddersfield

A Dec. 14, 2015 University of Huddersfield (UK) press release, which originated the news item, expands on the theme (Note: Links have been removed),

Infections contracted during surgical operations are a serious healthcare problem, leading to death in some cases.  Now, a research project at the University of Huddersfield is investigating the use of nanoparticles as a way to disinfect wounds.  It could prove to be much more effective than existing techniques because the particles would be tiny enough to enter the skin via hair follicles, ensuring much better penetration of the area affected by surgery.

The University’s Head of Pharmacy, Professor Barbara Conway (…), has developed the nanoparticle concept and it will now be further refined during a doctoral programme that she supervises.  Syrian-born [emphasis mine] researcher Khaled Aljammal has begun work on the project and receives funding via a new scheme, which means he is part of a network of bioscience and health researchers at go-ahead universities around the UK.

The issue addressed by Professor Conway’s project is that of surgical site infections, or SSIs.  It is estimated that every year, five per cent of patients who undergo surgery in England and Wales develop one of these infections and they are major source of prolonged illness and a significant cause of death in patients.  Also, they add strain on healthcare resources and fighting the infections is becoming more difficult because of growing resistance to antibiotics.

More effective use of antiseptics to treat the area affected by surgery is vital.  Professor Conway’s strategy is to develop a system of delivering the antiseptic drugs via minute particles less than a billionth of a metre in dimension.

“Making them nanoparticle size will help them to carry things into the skin better than current antiseptic regimes,” said the Professor.  “We think they will penetrate the skin better by the hair follicle route – and that is the site where bacteria will sit in the skin.”

Professor Conway – who is a member of the University of Huddersfield’s Institute of Skin Integrity and Infection Prevention – has been working for several years on methods for improving the delivery of antiseptics to reduce the incidence of SSIs.  Now, she is exploring the use of nano-sized formulations that have an antiseptic drug incorporated into them.  They could be administered in the form of a liquids, gels or even creams.

Khaled Al-Jammal (…) will be carrying out lab-based research aimed at developing and demonstrating the practicality of nanoparticle drug delivery.  He has been awarded full funding through the recently-launched Doctoral Training Alliance (DTA), an initiative of University Alliance, the organisation that unites UK universities with a mission to provide high-quality teaching and research that makes a real-world impact.

The Syrian researcher is one of two University of Huddersfield researchers who have begun their doctoral programmes under the DTA.  His gained his first degree in his native Syria before relocating to the UK four years ago for a Master’s in Pharmaceutical Technology.  This was followed by a spell working as a formulation scientist for the company Lena Nanoceutics.

His passion for research then led him to apply for the DTA project supervised at Huddersfield by Professor Conway.  As the project progress, it is intended that scientific articles and presentations will reveal its findings and these will be used to inform improved strategies to reduce the incidence and severity of such infections.

While the UK seems to be opening up its arms to scientists and researchers from Syria in an understated way, the Germans are being more direct.

A welcome mat for Syrian scientists

A Dec. 17, 2015 Deutsche Forschungsgemeinschaft (DFG; German Research Foundation) press release on EurekAlert describes an initiative developed for refugee scientists,

The Deutsche Forschungsgemeinschaft (DFG, German Research Foundation) plans to help scientists and academics who have fled their home countries to participate in DFG-funded research projects and thus contribute to the integration of refugees in research and society. DFG President Professor Dr. Peter Strohschneider has presented a package of measures to the Joint Committee of Germany’s largest research funding organisation. The basic aim of these measures is to allow supplemental proposals to be submitted for existing funding projects which would enable the participation of qualified researchers or those in training.

“The integration of people who have been forced to flee in fear of their lives is a duty for all groups in society. The academic and research community, which has always been based on openness and plurality, can and must do its part,” said Strohschneider. “Although we cannot say for sure how many, it is certain that the people now coming to us as refugees include researchers at the training stage or people already established as researchers. We know this from enquiries that have already been sent to the DFG regarding funding opportunities.”

To use DFG funds to help improve the situation at least a little for refugee scientists and academics, there is no need to set up new funding programmes, the DFG President continued. In fact, there is already scope within existing project funding to integrate qualified individuals into funded projects. In particular, this can be achieved through supplemental proposals for existing projects, which the original applicants are free to submit in certain circumstances – for example if additional researchers, whose participation would bring additional benefit to the research, become available after the project is approved.

“We want to expressly encourage all higher education institutions and project leaders to make use of these additional opportunities,” said Strohschneider.

Various concrete options are available to refugees with an academic research background. For the short-term integration of refugees at all academic qualification levels, supplemental proposals can be submitted for guest funding. For the longer-term integration of established researchers, the Mercator module is a suitable option. This can be used to cover accommodation and travel costs and also provide remuneration at a level which, as with guest funding, is based on academic qualification. Both guest funding and Mercator funding can be applied for in all DFG funding programmes. The budget for this will be dependent on the number of people who can be integrated in funded projects in this way.

Refugee scientists and academics can also participate in Research Training Groups, Collaborative Research Centres and other DFG-funded coordinated projects. The financial resources for this do not have to be specially requested with a supplemental proposal; appropriate measures can also be financed from previously approved funds. For example, refugees with a bachelor’s degree or comparable qualification can receive a qualifying fellowship for later doctoral research in a Research Training Group or be accepted directly into such a group.

Project leaders and higher education institutions are responsible for deciding how researchers should be integrated in a project, said the DFG President. It is also up to the higher education institutions to work out the legal details, such as appraisal of academic qualifications or the signing of fellowship or employment contracts.

Strohschneider concluded: “We as the DFG want to create the financial and organisational framework needed for participation in the projects we fund in an efficient, flexible way. We are confident that this will make a positive contribution to the integration of refugees in our research system and our society.”

I have yet to hear of any other countries specifically focused on refugee scientists but perhaps this is just the beginning.

Nanodiamond alternative to organic fluorophores to view inside living human cells

No sooner is a Nobel prize (2014) awarded for nanoscopy which makes use of fluorescence to observe processes in living cells than there is an announcement about a new technique that avoids fluorescence and its attendant shortcomings. From an Oct. 27, 2014 news item on Nanowerk (Note: A link has been removed),

Nanodiamonds are providing scientists with new possibilities for accurate measurements of processes inside living cells with potential to improve drug delivery and cancer therapeutics.

Published in Nature Nanotechnology (“Coherent anti-Stokes Raman scattering microscopy of single nanodiamonds”), researchers from Cardiff University have unveiled a new method for viewing nanodiamonds inside human living cells for purposes of biomedical research.

An Oct. 27, 2014 Cardiff University (Wales) news release, which originated the news item, explains why the use of nanodiamonds is superior to the use of organic flurophores,

Nanodiamonds are very small particles (a thousand times smaller than human hair) and because of their low toxicity they can be used as a carrier to transport drugs inside cells. They also show huge promise as an alternative to the organic fluorophores usually used by scientists to visualise processes inside cells and tissues.

A major limitation of organic fluorophores is that they have the tendency to degrade and bleach over time under light illumination. This makes it difficult to use them for accurate measurements of cellular processes. Moreover, the bleaching and chemical degradation can often be toxic and significantly perturb or even kill cells.

There is a growing consensus among scientists that nanodiamonds are one of the best inorganic material alternatives for use in biomedical research, because of their compatibility with human cells, and due to their stable structural and chemical properties.

Previous attempts by other research teams to visualise nanodiamonds under powerful light microscopes have run into the obstacle that the diamond material per se is transparent to visible light. Locating the nanodiamonds under a microscope had relied on tiny defects in the crystal lattice, which fluoresce under light illumination.

Production of the defects proved both costly and difficult to realise in a controlled way. Furthermore, the fluorescence light emitted by these defects, and in turn the image gleaned from the microscopic exploration of these flawed nanodiamonds, is sometimes also unstable.

In their latest paper, researchers from Cardiff University’s Schools of Biosciences and Physics showed that non-fluorescing nanodiamonds (diamonds without defects) can be imaged optically and far more stably via the interaction between the illuminating light and the vibrating chemical bonds in the diamond lattice structure which results in scattered light at a different colour.

The paper describes how two laser beams beating at a specific frequency are used to drive chemical bonds to vibrate in sync. One of these beams is then used to probe this vibration and generate a light, called coherent anti-Stokes Raman scattering (CARS).

By focusing these laser beams onto the nanodiamond, a high-resolution CARS image is generated. Using an in-house built microscope, the research team was able to measure the intensity of the CARS light on a series of single nanodiamonds of different sizes.

The nanodiamond size was accurately measured by means of electron microscopy and other quantitative optical contrast methods developed within the researcher’s lab. In this way, they were able to quantify the relationship between the CARS light intensity and the nanoparticle size.

Consequently, the calibrated CARS signal enabled the team to analyse the size and number of nanodiamonds that had been delivered into living cells, with a level of accuracy hitherto not achieved by other methods.

Professor Paola Borri from the School of Biosciences, who led the study, said: “This new imaging modality opens the exciting prospect of following complex cellular trafficking pathways quantitatively with important applications in drug delivery. The next step for us will be to push the technique to detect nanodiamonds of even smaller sizes than what we have shown so far and to demonstrate a specific application in drug delivery.”

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

Coherent anti-Stokes Raman scattering microscopy of single nanodiamonds by Iestyn Pope, Lukas Payne, George Zoriniants, Evan Thomas, Oliver Williams, Peter Watson, Wolfgang Langbein, & Paola Borri. Nature Nanotechnology (2014) doi:10.1038/nnano.2014.210 Published online 12 October 2014

The paper is behind a paywall but there is a free preview with ReadCube Access.

For anyone who’d like to read more about fluorescence and its use in nanoscopy there’s my Oct. 8, 2014 posting about the 2014 Nobel Prize in Chemistry and in my Oct. 27, 2014 posting about a specific use for determining how bipolar disorder may affect the brain.

Freezing transient events (frozen magnetic monopoles)

A Jan. 20, 2014 news item on Nanowerk highlights a new phase in laboratory physics (Note: A link has been removed),

Many of the most interesting things in nature – from spectacular lightning strikes to the subtlety of life itself – are transient, or far-from-equilibrium. To discover the secrets of far from equilibrium states, physicists need simple yet appealing laboratory systems. Now a researcher at the London Centre for Nanotechnology [UK] has collaborated with workers in Grenoble (France), Cardiff [Wales], Oxford [UK] and Kitakyushu (Japan), to create just such a system in the magnetic material known as “spin ice” (“Far-from-equilibrium monopole dynamics in spin ice”).

The Jan. 19 (?), 2014 (?) London Centre for Nanotechnology (LCN) research brief by Steve Bramwell, which originated the news item. explains ‘spin ice’ in greater detail and the trickery employed by the scientists’,

Spin ice is an unusual magnetic material in that it contains the magnetic equivalent of electrical charges – so called magnetic monopoles. It has attracted great interest on account of the currents of these charges forming a magnetic equivalent of electricity or “magnetricity”.

The number of magnetic monopoles in spin ice diminishes as the temperature goes down in much the same way as does the number of electrical charge carriers in semiconducting materials such as silicon – the basis of the electronics industry. The monopoles or charges disappear at low temperatures by positive and negative charges annihilating each other.

The researchers found a trick that used magnetic fields to create a hot “gas” of magnetic monopoles in very cold surroundings. The surroundings then sucked the heat out of the magnetic monopole gas, resulting in many magnetic monopoles trapped at a fraction of a degree above the absolute zero. The frozen monopoles no longer annihilated each other but instead could be made to flow by applying magnetic fields.

“Our low temperature experiments will tell us a lot about how magnetic monopoles move, as well as about the physics of far-from equilibrium systems in general” explains Prof. Steve Bramwell.

The researchers have provided this artist’s illustration of their work,

Figure: Artist’s impression of a hot gas of magnetic monopoles in very cold surroundings. Eventually the surroundings suck the heat out of the monopole gas leaving it frozen at low temperature. [downloaded from http://www.london-nano.com/research-and-facilities/highlight/frozen-magnetic-monopoles-create-new-laboratory-physics]

Figure: Artist’s impression of a hot gas of magnetic monopoles in very cold surroundings. Eventually the surroundings suck the heat out of the monopole gas leaving it frozen at low temperature. [downloaded from http://www.london-nano.com/research-and-facilities/highlight/frozen-magnetic-monopoles-create-new-laboratory-physics]

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

Far-from-equilibrium monopole dynamics in spin ice by C. Paulsen, M. J. Jackson, E. Lhotel, B. Canals, D. Prabhakaran, K. Matsuhira, S. R. Giblin, & S. T. Bramwell. Nature Physics (2014) doi:10.1038/nphys2847 Published online 19 January 2014

This paper is behind a paywall with several payment options.