Innovation and Technology Weekly – No. 35, 2013

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Issue 35, 2013

This week's headlines:

Uncool quantum state survives for record 40 minutes
November 14, 2013

Room temperature phosphorous atoms have been placed in a fragile quantum state called a superposition and survived for a leisurely 39 minutes - long enough for each one to perform 2m calculations if they were to form the guts a quantum computer. The finding by researchers from Simon Fraser University in Canada could herald the widespread use of these futuristic machines.

Ordinary computers store data as bits that are either 1s or 0s, but quantum computers have qubits, which are in a state of superposition, and can be both at the same time. This property has the power to crunch numbers much more rapidly than ordinary computers. Unfortunately, superpositions are very delicate, meaning most current quantum computers need to be chilled to near absolute zero to work properly. That limits their use to highly specialised buildings and laboratories.

To create a room temperature superposition the team focused on a component of a quantum computer - the qubit storage system, which holds quantum information to be processed. The team used a small slab of silicon infused with phosphorus atoms, which serve as the qubits. Each atom's nucleus has a property called spin that can point in different directions - spin up corresponds to a 0, while spin down is a 1, and any other angle is a superposition of the two.

First they placed the silicon in liquid helium, chilling it to just 4.2 degrees above absolute zero, before using a magnetic field to place each qubit in a superposition. Suspecting that electrons whizzing around in the phosphorous atoms might play a role in destroying the superposition, the team zapped the atoms with a laser first, removing an electron from each. The technique seemed to work. The superposition lasted for three hours at this low temperature, when previous similar experiments had only lasted for three minutes. When they raised the temperature to 25 °C the normally fragile quantum state survived for 39 minutes.

Full story: New Scientist / Science Back to top

How biology helps scientists optimize battery design
November 15, 2013

Lithium-air batteries have become a hot research area in recent years: They hold the promise of drastically increasing power per battery weight, which could lead, for example, to electric cars with a much greater driving range. But bringing that promise to reality has faced a number of challenges, including the need to develop better, more durable materials for the batteries' electrodes and improving the number of charging-discharging cycles the batteries can withstand.

Now, MIT researchers have found that adding genetically modified viruses to the production of nanowires and which can serve as one of a battery's electrodes - could help solve some of these problems. The key to their work was to increase the surface area of the wire, thus increasing the area where electrochemical activity takes place during charging or discharging of the battery.

The researchers produced an array of nanowires, each about 80nm across, using a genetically modified virus called M13, which can capture molecules of metals from water and bind them into structural shapes. In this case, wires of manganese oxide were actually made by the viruses. But unlike wires 'grown' through conventional chemical methods, these virus-built nanowires have a rough, spiky surface, which dramatically increases their surface area, which can provide a big advantage in lithium-air batteries' rate of charging and discharging.

The process can be carried out at room temperature using a water-based process. Also, rather than isolated wires, the viruses naturally produce a three-dimensional structure of cross-linked wires, which provides greater stability for an electrode. A final part of the process is the addition of a small amount of a metal, which greatly increases the electrical conductivity of the nanowires and allows them to catalyze reactions that take place during charging and discharging.

Full story: TG Daily / Nature Communications Back to top

Hydrogen phone chargers to keep Africans connected
November 14, 2013

African smartphone users will soon have an alternative means to get round the power shortages afflicting much of the continent - a portable charger that relies on hydrogen fuel cells. British company Intelligent Energy plans to roll out 1 million of the new chargers in mid-December, mainly in Nigeria and South Africa, after successfully testing them in Nigeria over the last five months.

The chargers are designed to back up the spread of smartphones and tablets across countries where cellphones have already helped to transform lives and businesses. Industry body GSMA, which represents about 800 of the world's mobile operators, said in its latest report that smartphones were key to boosting mobile internet access in sub-Saharan Africa where current penetration of 4% of the population lags the global average of 17%. Ericsson predicts that smartphone traffic in Africa will increase tenfold between 2013 and 2019, when around 476 million devices will be in use.

The hydrogen chargers, which fit easily into a handbag, consist of a fuel cell and a non-disposable cartridge that can be detached when exhausted. Consumers can expect to pay less than USD 5 dollars to 'refuel' a cartridge of the charger. This would translate to a cost of less than USD 1 to charge a phone. The final costs will ultimately depend on how telecoms companies market and sell the product.

Other companies, such as Dubai-based developer Solarway, have launched solar powered kiosks designed for communities that are not linked to a power grid, each capable of charging up to 40 cell phones a day.

Full story: Reuters Back to top

Stringent statistics make better science
November 12, 2013

Many scientific studies are coming to the wrong conclusion simply because the standards for statistical significance are too low, argues a US statistician. The finding may explain the growing number of studies that cannot be replicated, because, says Valen Johnson of Texas A&M University, such studies may not have found a real result in the first place. The problem is worst in the social and biological sciences.

Johnson says more stringent statistical tests should be required before a result is accepted. Traditionally, scientists test an alternative hypothesis against the 'null hypothesis' - which represents the status quo, or lack of an effect. When a result is obtained in an experiment, a decision is made whether to accept or reject the null hypothesis. The null hypothesis is rejected, and alternative adopted, only if the probability of getting such an extreme result is lower than a certain value under the assumption that the null hypothesis is true. Often a 'P value' of 0.05 or 'significance at the 5% level' is used.

But people often misinterpret a P value of 0.05 for a test statistic as meaning that there is only a 5% chance that the null hypothesis is true. What the P value actually means is that there is a 5% probability of results as extreme as these occurring when there is really no difference occurring in the experiment - a drug has no effect for example.

Classical statistical tests leading to P values are popular among scientists, but there's also another approach known as Bayesian statistics. The Bayesian approach genuinely compares the null hypothesis with an alternative hypothesis and produces a Bayes factor - which must be high to favour the alternative hypothesis. Johnson has married up some special Bayesian statistical tests with the classical ones, enabling a direct connection to be made between P values and the chance that the null hypothesis is wrong. This enabled Johnson to work out just what a value of P=0.05 actually means in practice.

Full story: ABC Net Back to top

Researchers unveil 'shape-changing' technology
November 15, 2013

Researchers from MIT have come up with a device that, unlike a hologram, can render digital 3D content physically and which could change the way we interact with PCs.

Dubbed a 'dynamic shape display', the device called inFORM, can render 3D content physically, so that users can interact with digital information in a tangible way. It can also interact with the physical world around it by, for example, moving objects, such as a ball, on its table's surface. Remote participants in a video conference can also be displayed physically, allowing for what the MIT researchers call 'a strong sense of presence' and the ability to interact physically at a distance.

InFORM works by making use of a projector, an Xbox Kinect sensor, about 900 pins, linkages and actuators, and a computer. Each pin - which can move up and down about 100 millimetres - is about 30 millimetres x 30 millimetres and acts as a real-life pixel. The pins are spaced about a centimetre apart and controlled by microcontrollers that talk to each other on a very fast network. A projector is used to display colour on top of each pin and a Kinect is used for mid-air gestures and to track objects and touches on the table.

Full story: Sydney Morning Herald Back to top

Unmask Wikipedia sock puppets by the way they write
November 13, 2013

It's getting harder to trust what you read on Wikipedia. An army of shadowy fake accounts is manipulating the online encyclopaedia's entries for money and damaging the site's credibility. Last month, Wikipedia announced that it had blocked some 250 'sock puppet' accounts - fake accounts set up by users who are often paid by companies to edit articles in their favour. Now, researchers from the University of Alabama at Birmingham have developed a tool that analyses the way articles are written and spots if they are edited by the same person.

One of the big problems for Wikipedia editors trying to uncover such accounts is that the IP addresses of users can only be accessed by a few administrators because of the need for privacy. So editors have to rely on their own experience to determine whether multiple accounts are actually the work of a single individual.

The team wanted to know if they could use algorithms to unmask the sock puppets by analysing the language they use. The challenge in spotting similarities in writing styles is that, in Wikipedia editing, as in much of social media writing, the articles are so short that there is little material to work with. They looked at the editing notes for more than 600 of Wikipedia's sock-puppet investigations. These were used as the training material for an algorithm that scanned some 230 features of the writing, such as grammatical quirks. The team showed the algorithm could predict which accounts were puppet accounts with a 75% accuracy rate - defined as agreeing with the decision of Wikipedia's investigators.

The accounts problem is just the latest issue to plague Wikipedia. It has been criticised because its editors are predominantly white, Western and 90% male, which skews both the articles it covers and their content.

Full story: New Scientist Back to top

Locust eardrum is a tiny frequency analyser
November 12, 2013

Locusts have a highly integrated and miniaturized hearing system that bears little resemblance to either the human ear or an electronic microphone, according to researchers from the University of Bristol who have done a detailed study of how the insects detect and process sounds. The research could lead to the development of microphones and sensors that are much smaller and simpler, yet less fragile, than the existing technologies.

Locusts and other insects are too small to accommodate the kind of highly developed hearing systems that are found in some larger animals. Locusts' ears are much simpler and all of the necessary functions are performed by the eardrum. The Bristol team used a laser Doppler vibrometer to analyse how a locust's eardrum membrane responded to incoming sound waves that were produced by a loudspeaker.

The team scanned the laser over the surface of the membrane, where they measured tiny picometre out-of-plane vibrations induced by the sound waves. They found that for low-frequency sounds, the membrane vibrated in such a way that both groups of cells were mechanically excited. But high-frequency sounds managed to excite one group only - meaning that the eardrum behaved like a basic, but efficient, frequency analyser.

The researchers then studied the membrane's nanostructure. The waves caused by low-frequency sounds will travel completely across the membrane, where low-frequency-sensitive neurons attach to the membrane. But high-frequency waves will only travel half that distance, stopping at the attachment point of high-frequency neurons. The team also found that the energy density contained in the travelling wave was amplified by as much as 56,000 times as it travelled across the eardrum. This means that the shape of the membrane is such that acoustic energy is collected by the surface of the eardrum and then focused towards the receptor cells.

Full story: PhysicsWorld / Journal of the Royal Society Interface Back to top

Pollution detector designed to protect heritage sites
November 08, 2013

A simple detector could help conservators at World Heritage sites in the developing world understand and protect against atmospheric pollutants that can damage valuable artefacts. The pollutant-measuring device has been prototyped by Henoc Agbota, an engineer at University College London, UK.

Agbota's work was prompted by last year's decision by UNESCO that its World Heritage Committee would begin asking their certified sites to provide yearly figures for atmospheric pollutant levels. In response, Agbota surveyed 25 developing world sites and found that few had the capacity to do this.

Almost three-quarters of the respondents to Agbota's survey reported observing damage to objects that they attributed to pollution. This took the form of particle deposits, corrosion and the formation of 'black crusts' on artefacts.

Agbota hopes his device will help to avoid this damage. It consists of a series of so called piezoelectric quartz crystals - which generate electric currents as they expand or contact by minute amounts - coated with varying thicknesses of copper, iron, nickel or tin. As pollutants absorb to these metallic surfaces, they change the crystals' mass, altering the electrical output and allowing pollution levels to be calculated. The prototype can detect oxides of sulphur and nitrogen, ozone and humidity - all of which can accelerate artefact degradation.

Full story: SciDev Back to top

Are social networks making us smarter?
November 14, 2013

The secret to why some cultures thrive and others disappear may lie in our social networks and our ability to imitate, rather than our individual smarts, according to a University of British Columbia study.

The study shows that when people can observe and learn from a wider range of teachers, groups can better maintain technical skills and even increase the group's average skill over successive generations. The findings show that a larger population size and social connectedness are crucial for the development of more sophisticated technologies and cultural knowledge, according to the researchers behind the study.

For the study, participants were asked to learn new skills - digital photo editing and knot-tying - and then pass on what they learned to the next 'generation' of participants. The groups with greater access to experts accumulated significantly more skill than those with less access to teachers. Within ten 'generations', each member of the group with multiple mentors had stronger skills than the group limited to a single mentor.

Groups with greater access to experts also retained their skills much longer than groups who began with less access to mentors, sustaining higher levels of 'cultural knowledge' over multiple generations.

According to the researchers, the study has important implications for several areas, from skills development and education to protecting endangered languages and cultural practices.

Full story: TG Daily / Proceedings of the Royal Academy: Biological Sciences Back to top