Issue no. 18, 2010
Published: May 28, 2010 |
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 Chemists report promising advance in fuel-cell technology |
| Seven atom transistor sets the pace for future PCs |
| Scientist is first man to be 'infected' by computer virus |
| Scientists devise algorithm to detect sarcasm |
| Movies manipulate our primal response |
|
| Chemists report promising advance in fuel-cell technology |
Creating catalysts that can operate efficiently and last a long time is
a big barrier to taking fuel-cell technology from the lab bench to the
assembly line. The precious metal platinum has been the choice for many
researchers, but platinum has two major downsides: It is expensive, and
it breaks down over time in fuel-cell reactions.
In a new study, chemists at Brown University report a promising advance.
They have created a unique core and shell nanoparticle that uses far
less platinum yet performs more efficiently and lasts longer than
commercially available pure-platinum catalysts at the cathode end of
fuel-cell reactions.
The research team created a five-nanometre palladium (Pd) core and
encircled it with a shell consisting of iron and platinum (FePt). The
trick was in moulding a shell that would retain its shape and require the
smallest amount of platinum to pull off an efficient reaction. The team
created the iron-platinum shell by decomposing iron pentacarbonyl
[Fe(CO)5] and reducing platinum acetylacetonate [Pt(acac)2]. The result
was a shell that uses only 30% platinum. The researchers say they expect
they will be able to make thinner shells and use even less platinum.
In tests the palladium/iron-platinum nanoparticles generated 12 times
more current than commercially available pure-platinum catalysts at the
same catalyst weight. The output also remained consistent over 10,000
cycles, at least ten times longer than commercially available platinum
models that begin to deteriorate after 1,000 cycles. |
| PhysOrg / Brown University
May 24, 2010 |
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| Seven atom transistor sets the pace for future PCs |
Researchers at the University of New South Wales, Australia, have shown
off a transistor made from just seven atoms. If the transistor can be
made in large numbers it could mean chips with components up to 100
times smaller than on existing processors. The scientists hope it is
also a step towards a solid-state quantum computer.
The transistor is not the smallest ever created as two research groups
have previously managed to produce working single-atom transistors.
However, the device is many times smaller than the components found in
chips in contemporary computers. On chips where components are 22
nanometres in size, transistor gates are about 42 atoms across. The
working transistor was created by replacing seven atoms in a silicon
crystal with phosphorus atoms.
Moore's Law predicts that the amount of memory that can fit on a given
area of silicon, for a fixed cost doubles every 12-18 months. The limit
of this prediction is being tested as components get ever smaller and
their computationally useful properties become less reliable.
The researchers are a long way from a commercial process because the
tiny transistor they created was handmade. The team used a scanning
tunnelling microscope to move the phosphorus atoms into place. The work
on the tiny transistor is being carried out as part of a larger project
to create a quantum computer. |
| BBC News / Nature Nanotechnology
May 24, 2010 |
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| Scientist is first man to be 'infected' by computer virus |
A British scientist has laid claim to being the first man to be infected
by a computer virus, after he used a contaminated chip implanted in his
hand to attack a lab security system.
Dr Mark Gasson programmed the microchip, similar to those used to 'tag'
pets, to remotely open his lab's security doors and unlock his mobile
phone before having it inserted under his skin. But he also infected the
implant with a virus, to prove it could be transferred as the chip and
the security system wirelessly exchanged electronic data.
The virus could then have been passed on to other devices interacting
with the control system, such as colleagues' swipe cards, in the same
way viruses are able to spread across computer networks. The results
raise the possibility that in the future, increasingly advanced medical
devices such as pacemakers and inner ear implants could become
vulnerable to cyber attacks from other human implants.
Dr Gasson stressed it is not currently thought possible to exploit
medical devices such as pacemakers because they have not been analysed
for flaws, but said they could theoretically be vulnerable. |
| Daily Telegraph
May 26, 2010 |
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| Scientists devise algorithm to detect sarcasm |
A computer algorithm capable of identifying sarcasm in written text has
been developed by Israeli researchers. The novel formula could pave the
way for more sophisticated communication between humans and computers.
Devised by computer scientists at The Hebrew University in Jerusalem,
the algorithm has been programmed to recognise sarcasm in lengthy texts
by analysing patterns of phrases and punctuation often used to indicate
irony. In tests on 66,000 product reviews posted on the Amazon shopping
website, the algorithm had an impressive 77 per cent success rate in
picking out sarcastic comments - arguably higher than some humans.
The researchers 'trained' the algorithm to recognise sarcasm by teaching
it nearly 5,500 sentences from Amazon reviews that volunteers had marked
as either sarcastic or non-sarcastic. From this list of phrases, the
algorithm was taught to recognise patterns of words commonly used by
writers to show that they do not mean to be taken literally.
The algorithm was tested on tens of thousands of other Amazon reviews
which had also been tagged for sarcasm, or otherwise, by human readers.
It produced accurate answers in 77% of cases. |
| Daily Telegraph
May 19, 2010 |
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| Movies manipulate our primal response |
Evolutionary biologists say they have the scientific backing to confirm
suspicions that movies exploit our innate response to alarm and distress
calls. To stoke fear and excitement or make it subside, movie sound
engineers manipulate an audio pattern called 'non-linear vocalisation'.
Among land vertebrates, 'non-linear vocalisation' applies to screeches,
screams and calls, such as a baby's cry or a threat warning, that are
louder, usually higher pitched and often sudden. Designed to stand out
against lower-frequency background noise, they have been used by humans
and animals for millions of years to capture the attention of others in
their community.
A team from the University of California, Los Angeles, compiled a list
of the 102 most popular films in Western cinema, as determined by public
polls posted on Internet sites. Twenty-four of the movies were
adventure, 35 were dramatic, 24 were horror and 19 were war films. The
researchers then extracted an iconic scene from the movie, documented
whether it had sound effects or accompanying music and crunched it
through software that pinpointed changes in frequency and volume.
Adventure movies were big on male screams while horror movies had many
noisy screams but little accompanying music, the investigators found.
War films had sharp fluctuations (up and down) in volume, while dramatic
films used lower frequencies of noise, fewer abrupt changes in volume
and more musical accompaniment than the other genres. |
| ABC / AFP / Biology Letters
May 26, 2010 |
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