Innovation and Technology Weekly – No. 2, 2012

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Issue 2, 2012

This week's headlines:

Magnetic soap made for oil spills
January 24, 2012

Scientists have created the world's first soap that can be controlled by magnets. The work may revolutionise industrial cleaning products and the response to environmental disasters such as oil spills, reports the research team from Bristol University in England.

The soap works like ordinary soap - breaking up the oily, grimy particles it touches and clumping it all into a drop. Only these clumps can be controlled simply by turning on a magnet. The property could, for example, allow environmental cleanup crews to dump soap onto an oil spill, and then turn on a magnet to remove it all from the environment.

The soap was created by dissolving iron in a range of standard soap materials made of chlorine and bromine ions, similar to those found in mouthwash and fabric softener. Soap molecules have an oil-loving part and a water-loving part. The team left the oil-loving part alone, but made the water-loving part magnetic.

The addition of iron creates metallic centres within the soap particles that are big enough be magnetically attractive. Simply by turning on or off a magnet, researchers can change the electrical conductivity of the soap, its melting point, and the size and shape of aggregates, for example. These properties are traditionally controlled with the addition of electrical charge, or changing the pH or temperature of a system. All of these alter the system and can cost money to remediate.

The magnetic property also makes the soap easier to collect and remove from a system once it has done its job. This could prove particularly useful, for example, in cleaning up oil spills.

Full story: MSNBC Back to top

'Cloaking' a 3-D object from all angles demonstrated
January 26, 2012

Using a shell of plasmonic material researchers at the University of Texas at Austin have 'cloaked' a three-dimensional object, making it invisible from all angles, for the first time. However, the demonstration works only for waves in the microwave region of the electromagnetic spectrum. The idea could find first application in high-resolution microscopes.

Plasmonic materials can be designed to have effects on the fields that are precisely opposed to those of the object. The plasmonic material shell is, in essence, a photo-negative of the object being cloaked. As a result, the cloak has to be tailored to work for a given object. If one were to swap different objects within the same cloak, they would not be as effectively hidden.

But the success with the cylinder suggests further work with different wavelengths of light is worth pursuing. However, the idea is unlikely to work at the visible light part of the spectrum.

Full story: BBC News / Journal of Physics Back to top

Breakthrough in quest to turn seaweed into biofuels
January 19, 2012

Brown seaweed's potential as a vast source of biofuels has been highlighted with the announcement that scientists have found a way of converting all its major sugars into ethanol.

A team reported in Science that it has engineered a microbe that will convert the sugars to ethanol, overturning one of the main obstacles to making the use of brown macroalgae, or seaweed, as a biofuel feedstock competitive. The prospective ethanol yield from brown seaweed is approximately two times higher than that from sugarcane and five times higher than maize, from the same area of cultivation.

But its full potential cannot be reached because of the inability of industrial microbes to break down alginate, one of the three most abundant sugars in brown seaweed, commonly known as kelp, which is the most widely grown seaweed in the world.

Now, researchers based in Chile, France and the United States say that they have developed the first microbe capable of fermenting all the major sugars found in a common species of brown seaweed. The team engineered Escherichia coli bacteria, which has the natural ability to metabolise glucose and mannitol - the other two main sugars in brown seaweed - and Vibrio splendidus, a microorganism containing all necessary genes to metabolise alginates. As a result, the scientists were able to get a yield of bioethanol directly from seaweed equivalent to 15,000-20,000 litres per hectare per year.

Full story: SciDev / Science Back to top

Scorpions inspire tougher surfaces for machinery
January 25, 2012

Taking inspiration from the yellow fattail scorpion, which uses a bionic shield to protect itself against scratches from desert sandstorms, scientists have developed a new way to protect the moving parts of machinery from wear and tear.

The team explain that 'solid particle erosion' is one of the important reasons for material damage or equipment failure. It causes millions of dollars of damage each year to helicopter rotors, rocket motor nozzles, turbine blades, pipes, and other mechanical parts. The damage occurs when particles of dirt, grit, and other hard material in the air, water, or other fluids strike the surfaces of those parts.

Filters can help remove the particles but must be replaced or cleaned, while harder, erosion-resistant materials cost more to develop and make. In an effort to develop better erosion-resistant surfaces the team sought the secrets of the yellow fattail scorpion for the first time. The scorpion evolved to survive the abrasive power of harsh sandstorms.

They studied the bumps and grooves on the scorpions' backs, scanning the creatures with a 3D laser device and developing a computer program that modelled the flow of sand-laden air over the scorpions. The team used the model in computer simulations to develop actual patterned surfaces to test which patterns perform best. At the same time, the erosion tests were conducted in the simple erosion wind tunnel for groove surface bionic samples at various impact conditions. Their results showed that a series of small grooves at a 30-degree angle to the flowing gas or liquid give steel surfaces the best protection from erosion.

Full story: R&D Magazine / Langmuir Back to top

Better mathematics boosts image-processing algorithm
January 19, 2012

The Fourier transform, which splits a complicated signal into individual pure frequencies, was devised over 200 years ago but only became widely used after the development of an algorithm called the fast Fourier transform in the 1960s. Now, computer scientist at the Massachusetts Institute of Technology have developed a Fourier transform algorithm that is potentially hundreds of times faster still.

Splitting a signal using the Fourier transform reveals how much different frequency components contribute to an overall sound or image. In some cases, a wide range of frequencies contribute equally, but often a small number dominate. The MIT algorithm improves performance on signals of the latter type, known as sparse signals.

The team discovered they could quickly identify the important frequencies in a sparse signal by combining two existing signal filters to create a new, more efficient one. This filter works by dividing the range of frequencies into sets, then identifying which sets contain important frequencies.

Having found the key sets, the team had to identify the exact important frequency within each set. The team applied a signal-processing technique normally used to improve wireless communications. This is based on the idea that the most important frequency will modulate all the other signals in the set. Sampling the set rapidly at different times reveals the frequency of this dominating signal. The new technique can process sparse signals up to 10,000 faster than the old algorithm.

Full story: New Scientist Back to top

Software could spot face-changing criminals
January 18, 2012

Criminals who go under the knife in an effort to evade capture might want to consider an alternative disguise, thanks to a new technique for matching faces before and after plastic surgery developed by researchers at the University of Notre Dame, Indiana.

The researchers were inspired by a facial-recognition technique called sparse representation, which matches an image of a face by comparing it with combinations of individual features from faces already recorded in a database. If the closest matching combination turns out to be made up of features mostly drawn from one person in the database, it is a good bet to say the target image is also of that person. But if the best match combines features pulled from images of many different people then the system has failed to identify the new face.

However, to function properly sparse representation requires multiple images of each person in the database, so it does not work with pairs of before and after surgery pictures alone. The new system does. It uses two databases: a general one full of random faces, and another containing all of the 'before' pictures - akin to police mugshots. When a target 'after' picture is analysed, a composite picture as similar as possible is created from the features of people in the general database.

All of the 'before' pictures go through the same process. If the composite picture created using the 'after' picture matches closely with any of the composite pictures derived from the 'before' pictures, the two are declared a match.

The team found that while surgery changes the appearance of a face, many individual features stay the same, and matching based on the nose or eyes alone was actually more accurate than some existing whole-face techniques. Combining the matches of all facial features gave the team a 78% success rate when comparing pre- and post-surgical photos.

Full story: New Scientist Back to top

Vultures skeletonise corpse for the sake of forensics
January 25, 2012

Ever entertained the idea of leaving your body to science? Even if you have, you can scarcely have considered the strange fate of one donated corpse that has just been revealed: a donor's body was left in a Texan wilderness so that vultures could scavenge and 'skeletonise' it - and distribute the remains far and wide.

This wasn't for some horror movie - even though the process was captured on video. The aim was to discover how long it takes vultures to discover a body, how long it takes to reduce a body to bones - and how far the creatures are likely to distribute the parts they don't eat. When human body parts are found in wilderness areas in the US, detectives can be at a loss as to the time of death. Has the body been attacked locally by animals? Or perhaps torn apart by a vultures?

Researchers from Texas State University placed a body in the grounds of the university's Forensic Anthropology Research Facility and left it monitored by a motion-sensing video camera. The camera was triggered after 37 days when a 30-strong wake of American black vultures discovered the body. They reduced it to bones in just five hours. Both results surprised the researchers: pigs have been found and consumed by vultures within 24 hours of being left in the facility. And the skeletonisation was much quicker than the day they had expected it to take. This will feed into future time-of-death calculations.

The spatial pattern of discarded body parts was mapped by the team using GPS over the next 15 weeks - as vultures came back and distributed the remains still further - and the researchers hope this dispersal pattern will aid future forensics work, too.

Full story: New Scientist / Forensic Science International Back to top

Discovery could lead to an exercise pill
January 11, 2012

Researchers at the Dana-Farber Cancer Institute in Boston have discovered a natural hormone that acts like exercise on muscle tissue-burning calories, improving insulin processing, and perhaps boosting strength.

The scientists hope it could eventually be used as a treatment for obesity, diabetes, and, potentially, neuromuscular diseases like muscular dystrophy.

The team showed that the hormone, which they named irisin, occurs naturally in both mice and humans. It pushes cells to transform from white fat-globules that serve as reservoirs for excess calories-into brown fat, which generates heat.

Mice given irisin lost a few grams in the first 10 days after treatment, the study shows, and certain genes involved in powering the cell were turned on. Irisin also appeared to reduce the damage done by a high-fat diet, protecting mice against diet-induced obesity and diabetes.

Full story: Technology Review / Nature Back to top