Issue no. 23, 2008
Published: Jul 11, 2008 |
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 Researchers claim superconductivity breakthrough |
| Japanese researchers build artificial DNA |
| MIT develops less-expensive way to shrink chip circuitry |
| Brain implant helps stroke victim speak again |
| Organic dye lets window panes harvest the Sun |
| Game theory could save the world |
| How jungle rot could power the future |
| Chip may speed up internet 100 times |
| Kodak develops 50-megapixel image sensor for digital cameras |
| Nuclear fallout used to spot fake art |
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| Researchers claim superconductivity breakthrough |
Scientists at the University of Cambridge have published details of a
key breakthrough in unravelling the mystery of room temperature
superconductivity.
They write that materials which could potentially transport electricity
with zero loss (resistance) at room temperature hold vast potential.
Some of the possible applications include supercomputers, magnetically
levitated trains, efficient magnetic resonance imaging, and lossless
power generators, transformers and transmission lines.
Creating such materials has long eluded scientists, but the materials
that are known to superconduct at the highest temperatures are ceramic
insulators that behave as magnets before 'doping'. 'Doping' is a method
of introducing impurities to a semiconductor to modify its electrical
properties. After doping charge carriers (holes or electrons) into these
parent magnetic insulators, they mysteriously begin to superconduct.
The Cambridge researchers have discovered where the charge 'hole'
carriers that play a significant role in the superconductivity originate
within the electronic structure of copper-oxide superconductors. |
| VNUnet UK / Nature
Jul 10, 2008 |
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| Japanese researchers build artificial DNA |
Japanese scientists from the University of Toyama say they have created
the world's first artificial DNA. The technology could be used in
immensely powerful DNA computers.
Biological computing has the potential to make silicon-based systems
obsolete and allow the development of tiny supercomputers many times
more powerful than today's systems. DNA computers are constructed by
using DNA as software and enzymes as hardware. By mixing the two and
monitoring the resulting reactions, simple computer calculations can be
performed.
The storage capacity of DNA is also far superior to that of silicon
systems. Half a kilo of DNA would have a greater storage capability than
all the hard drives in existence today. It is also much more power
efficient. The new discovery would allow scientists to build custom DNA
types optimised for computing. |
| VNUnet UK / Journal of the American Chemical Society
Jul 08, 2008 |
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| MIT develops less-expensive way to shrink chip circuitry |
Researchers at MIT have developed a relatively inexpensive technique for
shrinking the size of integrated circuitry found in microprocessors,
computer memory, and other applications. The new technique has the
potential of paving the way for next-generation computer components that
deliver higher performance at the same or less power than current
technology. This is the result of being able to pack more circuitry on
the same size surface. In addition, the technique could be used in the
development of circuitry for other applications, such as solar cells.
Specifically, the researchers have been able to etch 25-nanometer wide
electron-carrying paths that are 25 nanometres apart. The thinnest
circuitry available today in general microprocessors that are the brains
of home and business computers is 45 nanometres.
The accomplishment of the MIT team is not in the size, but in the fact
that it can etch the paths without the use of environmentally dangerous
chemicals and other materials that add to the infrastructure cost in
building today's processors. The new line-drawing method is similar to
using a comb with three of every four teeth missing to draw lines in the
sand. The researchers can move the comb over one line at a time to fill
in the gaps, using sound waves as a guide. The tool developed for the
process is called a nanoruler. |
| InformationWeek
Jul 09, 2008 |
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| Brain implant helps stroke victim speak again |
Nine years ago, a brain-stem stroke left Erik Ramsey almost totally
paralysed, but with his mental faculties otherwise intact. Today he is
learning to talk again. In 2004, Ramsey had an electrode implanted in
his speech-motor cortex by scientists at Neural Signals, US, who hoped
the signal from Ramsey's cortex could be used to restore his speech.
Interpreting these signals proved tricky, however. Fortunately, a team
from Boston University has been working on the same problem from the
opposite direction. They have used information from brain scans of
healthy patients to monitor neural activity during speech and found that
the brain signals do not code for words, but instead control the
position of the lips, tongue, jaw and larynx to produce basic sounds.
The Boston University group then developed software that could recognise
and translate the patterns of brain activity during speech. When they
teamed up with Neural Signals, they could use their software to
interpret the signals from Ramsey's implanted electrode and work out the
shape of the vocal tract that Ramsey is attempting to form. This
information can then be fed to a vocal synthesiser that produces the
corresponding sound. The software is now translating Ramsey's thoughts
into sounds in real time, so Ramsey hears his 'voice' as he makes a
sound, effectively bypassing the damaged region of his brain stem. |
| New Scientist
Jul 09, 2008 |
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| Organic dye lets window panes harvest the Sun |
Harvesting sunlight before turning it into electricity could become
easier thanks to an exotic organic dye developed at MIT. Coated onto an
ordinary sheet of glass, the dye traps light inside the glass allowing
it to be channelled to photovoltaic cells placed along the edges of the
sheet. The technique could turn up to 20% of incident light into
electricity at a fraction of the cost of conventional photovoltaic
cells.
One way to reduce the cost of photovoltaic power is to focus light from
a large area onto a small cell. In that way, a small cell can harvest
light from a larger area. But the collecting optics must track the Sun's
path across the sky, requiring expensive machinery and control systems.
The dye-covered glass works differently. The dye molecules absorb
sunlight over a wide range of visible wavelengths and then emit light at
a longer wavelength.
About 80% of the emitted light then becomes trapped within the glass by
an effect called total internal reflection, which guides the light
within the sheet in the same way it guides light through optical fibres.
Solar cells along the edges of the glass that are designed to work most
efficiently at the longer wavelength then convert this trapped light
into electricity. |
| New Scientist / Science
Jul 10, 2008 |
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| Game theory could save the world |
New hope that people around the world can work together to combat global
warming has come from a new theoretical study by researchers at the
University of Lisbon and the Free University of Brussels. The team has
been using 'game theory' - where mathematics is used to capture how
people deal with each other - to show that a classic problem that
undermines the ability of individuals to cooperate can be overcome, if
people are diverse enough, as is the case when it comes to the 6.5
billion citizens of planet Earth.
Working together for the common good is crucial for progress in any
society. But there is a basic problem with how to make the public share
responsibility for common problems, such as climate change. This was
illustrated by Garrett Hardin in his 1968 paper 'The tragedy of the
commons'. He used the example of a public pasture. Each herdsman will
keep adding cows to a common field, because the benefit of an additional
cow goes exclusively to the herdsman. Because the cost of overgrazing is
shared by all, the pasture will end up ruined.
Existing mathematical models treat individuals as equivalent, ignoring
real-life diversity and population structure. So the team made the
mathematics more realistic in this respect. The team shows that,
contrary to expectations, the temptation to cheat declines as society
becomes more diverse. Another discovery is that diversity also plays an
important role in wealth distribution. |
| Daily Telegraph
Jul 09, 2008 |
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| How jungle rot could power the future |
The genetics of 'jungle rot' may hold the key to more economical biofuel
in the near future. Ethanol, the most common biofuel, is primarily made
from grains, sugarcane and other crops. But it can also be made from
cellulose Found in stems, bark and other plant parts.
To break down cellulose into fermentable sugars, however, requires
special enzymes, called cellulases, which are expensive to produce. The
biofuel industry has primarily obtained cellulase from the fungi
Trichoderma reesei, which became infamous during World War II as jungle
rot. The green mould devoured military tents and uniforms in the South
Pacific.
To help reduce the cost of cellulase, an international group of
scientists organised by the US Department of Energy's Joint Genome
Institute (JGI, has now sequenced the DNA of one strain of T. reesei
from the Solomon Islands. The hope is that this genetic information
could allow the engineering of fungi or bacteria that can produce
enzymes more efficiently than the current approach. |
| MSNBC / LiveScience
Jul 09, 2008 |
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| Chip may speed up internet 100 times |
Scientists at the University of Sydney have developed a revolutionary
optical chip that could improve internet speeds to up to 100 times.
The device, a photonic integrated circuit, could overcome the gridlock
that occurs when information travelling along optical fibres at the
speed of light has to be processed by slow, old-fashioned electronic
components.
The chip, which the Australian team developed with Danish and Chinese
colleagues, is made from chalcogenide, with tiny channels etched into
the surface by lithographic techniques. The scratches on the surface of
the glass act as a guide or switch for incoming data, akin to a train
changing tracks, only rapidly. |
| The Age
Jul 10, 2008 |
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| Kodak develops 50-megapixel image sensor for digital cameras |
Eastman Kodak said it has developed a 50-megapixel image sensor for
digital cameras used by professional photographers.
The KAF-10100 produces exceptional resolution and detail in digital
camera photography by producing images with a pixel array of 8176 x
6132, the highest resolution available in the popular 48 mm x 36 mm
optical format used in medium-format photography, Kodak said.
Other features of the sensor include a newly designed 6-micron pixel
instead of the 6.8-micron pixels used in current products for the
commercial market. The smaller pixel reduces the 'click-to-capture' time
for better camera response, lower power consumption, and more vivid
colours. |
| InformationWeek
Jul 09, 2008 |
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| Nuclear fallout used to spot fake art |
Scientists and art historians have developed what they say is a
foolproof way of identifying forged works of art. They can distinguish
between art created before 1945 and that produced after that date by
measuring levels of the isotopes caesium-137 and strontium-90. These
isotopes do not occur naturally but are released into the environment by
nuclear blasts.
Over 2000 nuclear tests have been carried out since the first atomic
explosion took place in New Mexico in July 1945. Among the by-products
of these tests are caesium-137 and strontium-90, tiny quantities of
which make their way into the Earth's soil and plants. It is then via
the natural oils, such as linseed from the flax plant, that are used as
binding agents in paints that these isotopes end up in post-1945 art.
The patented technique involves extracting tiny (of the order of 1
square millimetre) samples from paintings. The team were able to show
that the two isotopes are not present in paintings from the first half
of the 20th century, but that there were traces in paintings done in the
1950s. |
| PhysicsWorld
Jul 04, 2008 |
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