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Deepwater Horizon oil spill Image: Oscar Garcia / Florida State University
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Issue no. 2, 2012 Published: Jan 27, 2012 |
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Magnetic soap made for oil spills | 'Cloaking' a 3-D object from all angles demonstrated | Breakthrough in quest to turn seaweed into biofuels | Scorpions inspire tougher surfaces for machinery | Better mathematics boosts image-processing algorithm | Software could spot face-changing criminals | Vultures skeletonise corpse for the sake of forensics | Discovery could lead to an exercise pill |
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| Magnetic soap made for oil spills |
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. |
| MSNBC
Jan 24, 2012 |
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| 'Cloaking' a 3-D object from all angles demonstrated |
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. |
| BBC News / Journal of Physics
Jan 26, 2012 |
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| Breakthrough in quest to turn seaweed into biofuels |
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. |
| SciDev / Science
Jan 19, 2012 |
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| Scorpions inspire tougher surfaces for machinery |
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. |
| R&D Magazine / Langmuir
Jan 25, 2012 |
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| Better mathematics boosts image-processing algorithm |
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. |
| New Scientist
Jan 19, 2012 |
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| Software could spot face-changing criminals |
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. |
| New Scientist
Jan 18, 2012 |
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| Vultures skeletonise corpse for the sake of forensics |
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. |
| New Scientist / Forensic Science International
Jan 25, 2012 |
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| Discovery could lead to an exercise pill |
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. |
| Technology Review / Nature
Jan 11, 2012 |
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