Issue no. 6, 2010
Published: Feb 12, 2010 |
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 Scientists seek better way to do climate report |
| NASA launches Solar Dynamics Observatory |
| Graphene transistor breaks new record |
| Sun-powered water splitter makes hydrogen tirelessly |
| Organic crystals promise low-power green computing |
| Google to offer 'ultra high-speed' broadband in US |
| Weed genes could help feed the world |
| World's most precise clock created |
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| Scientists seek better way to do climate report |
A steady drip of unsettling errors is exposing what scientists are
calling 'the weaker link' in the Nobel Peace Prize-winning series of
international reports on global warming. The flaws - and the erosion
they've caused in public confidence - have some scientists calling for
drastic changes in how future United Nations climate reports are done.
The work of the climate change panel, or IPCC, is often portrayed as one
massive tome. But it really is four separate reports on different
aspects of global warming, written months apart by distinct groups of
scientists. No errors have surfaced in the first and most well-known of
the reports, which said the physics of a warming atmosphere and rising
seas is man-made and incontrovertible. So far, four mistakes have been
discovered in the second report, which attempts to translate what global
warming might mean to daily lives around the world. That second report
at times relied on government reports or even advocacy group reports
instead of peer-reviewed research. Scientists say that is because there
is less hard data on global warming's effects.
In the journal Nature climatologists call for reform. Suggestions
include making the IPCC stronger and more independent, modelled on the
International Atomic Energy Agency, staffed by 200 full-time scientists
who produce biennial 'state-of-the-climate' reports and advise
governments on regional issues. Another idea is a Wikipedia-style IPCC,
with small groups of lead authors managing separate sections of the
website. In response, Chris Field of Stanford University, the new head
of the second report team, said that he welcomes the scrutiny and vows
stricter enforcement of rules to check sources to eliminate errors in
future reports; those are to be produced by the IPCC starting in 2013. |
| USA Today / SciDev
Feb 10, 2010 |
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| NASA launches Solar Dynamics Observatory |
NASA has launched an Atlas V rocket carrying a probe that the agency
says will study the sun in greater detail than ever before. NASA says
the first-of-its-kind observatory will provide a better understanding of
the sun and its role in space weather events such as solar flares.
The observatory is designed to deliver solar images with 10 times better
resolution than high-definition television. Its five-year mission aims
to determine how the sun's magnetic field is generated, structured and
converted into violent solar events like turbulent solar wind, solar
flares and coronal mass ejections, according to the agency.
The solar wind, a stream of electrically charged particles flowing from
the sun, fills the solar system with charged particles and magnetic
fields. Solar flares are explosions in the sun's atmosphere, the largest
of them equal to billions of one-megaton nuclear bombs. And coronal mass
ejections, or CMEs, are eruptions that launch solar material into space
at a high rate of speed.
Such events can put astronauts at risk, as well as aircraft flying over
Earth's North or South poles, and can disrupt satellite communications,
navigational systems and power grids. |
| CNN / NASA
Feb 11, 2010 |
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| Graphene transistor breaks new record |
IBM researchers have made the fastest graphene transistor ever, with a
cut-off frequency of 109 cycles/second (100 gigahertz). After further
downscaling and optimisation, the device could far outperform
conventional devices made from silicon, says the team.
Graphene - the one-atom-thick sheet of carbon discovered in 2004 - is
unusual since electrons can move through it at extremely high speeds
because they behave like relativistic particles with no rest mass. This,
and other unusual physical and mechanical properties, means that it
could replace silicon as the electronic material of choice and might be
used to make faster transistors than any that exist today.
Researchers at IBM's TJ Watson Research Center in New York began by
making high-quality graphene wafers by thermally decomposing a silicon
carbide (SiC) substrate. They then used these to make the
radio-frequency transistor, which comprises a metal top gate and a novel
gate insulator stack involving a polymer and a high dielectric constant
oxide. The gate length is relatively big at 240 nm, but it could be
scaled down in the future to further improve device performance.
The high-frequency transistor could find applications in communications
and imaging, including high-resolution radar, medical and security
imaging. The IBM researchers now plan to scale down their transistor,
improve graphene purity and optimize device architecture. |
| NanotechWeb / Science
Feb 05, 2010 |
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| Sun-powered water splitter makes hydrogen tirelessly |
Sunlight + water = hydrogen gas, in a new technique that can convert 60%
of sunlight energy absorbed by an electrode into the inflammable fuel.
To generate the gas researchers at the University of East Anglia in
Norwich, UK, dip a gold electrode with a special coating into water and
expose it to light. Clusters of indium phosphide 5 nanometres wide on
its surface absorb incoming photons and pass electrons bearing their
energy on to clusters of a sulphurous iron compound. This material
combines those electrons with protons from the water to form gaseous
hydrogen. A second electrode - plain platinum this time - is needed to
complete the circuit electrochemically.
Organic molecules have been used before to perform the same feat. But
they are quickly bleached by the sunlight they are collecting, rendering
them inefficient after a few weeks. The inorganic materials used in the
University of East Anglia's system are more resilient. Their first
generation proof of concept is 'a major breakthrough' in the field, they
say, thanks to its efficiency of over 60% and ability to survive
sunlight for two weeks without any degradation of performance.
The researchers now plan to refine the system, including lowering the
cost by making it with less expensive materials. |
| New Scientist / Angewandte Chemie International
Feb 11, 2010 |
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| Organic crystals promise low-power green computing |
A saffron-coloured crystal could provide a step towards greener
electronics. Some types of low-power computer memory store information
using metals that are ferroelectric, meaning they form positive and
negative poles when placed in an electric field. However, many of the
more common metals used are either rare or toxic.
Now researchers at the National Institute of Advanced Industrial Science
and Technology in Ibaraki, Japan, have discovered ferroelectric
behaviour in crystalline croconic acid, which contains just carbon,
oxygen and hydrogen.
Croconic acid was discovered 170 years ago but crystallised for the
first time within the past decade. When the team applied an electric
field to the crystals at room temperature they could reverse its
electric polarity.
The researchers noticed a small time lag between removing the field and
reversal of the crystal's polarity. This is typical of ferroelectrics
and a direct indication of the ability to store and switch an electrical
polarisation, according to the researchers. The finding suggests
croconic acid could be used in organic electronics. |
| New Scientist / Nature
Feb 10, 2010 |
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| Google to offer 'ultra high-speed' broadband in US |
Google is spreading its wings in yet another direction - this time as a
network provider, offering super-fast broadband to thousands of US
homes. It plans to build a fibre-optic network offering speeds of up to
1 gigabit per second to up to 500,000 homes. Google said it will compete
on price with other broadband providers offering much slower speeds.
Google already has a fibre network which connects its data centres,
speeds up search and lowers the cost of streaming video on YouTube. Now
it plans to take this to the next stage and connect that network
directly to consumers' homes. The network will be available for any
service provider to use and Google is asking interested parties, from
local government as well as members of the public, to sign up to the
plan. The offer is part of Google's expansion into controlling all
aspects of a web user's experience.
In late 2009 Google offered a service called public DNS, which it said
would speed up web browsing for users. The domain name system is a
series of databases that translate web addresses into computer readable
numbers called IP addresses. DNS requests are usually handled by a
person's Internet Service Provider (ISP). In November 2009, Google also
announced that it was working on a project to develop a faster version
of http - SPDY - to speed up the transfer of content over the web. |
| BBC News
Feb 10, 2010 |
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| Weed genes could help feed the world |
A humble weed native to the Mediterranean and Middle East and viewed by
gardeners as an invasive pest could hold the secret to boosting yields
of cereals and biofuels. Biologists from Oregon State University say
they have unravelled the genome of Brachypodium distachyon, a small wild
grass that offers big promise in plant biotechnology.
Also called purple false brome, this native of the Mediterranean and
Middle East is a plant of zero commercial or agricultural importance.
But its tiny, easily manipulated genetic code makes it ideal to serve as
a lab testbed for understanding more complex, valuable grasses.
Brachypodium is the first member of a sub-family of grasses called
Pooideae - a category that includes wheat, barley, forage crops and
switchgrass, which is of major interest for biocrop production - to be
sequenced. The grass family has two other sub-families, Ehrhartoideae
and Panicoideae, which include corn and rice. These important cereals
have already had their genomes unravelled.
Genomic research entails pinpointing genes and understanding how they
work in an organism. In plants, this can unlock knowledge of, for
example, genes that confer resistance to drought, offer a bigger head of
food grains or boost yields of natural oils that can be used as
biofuels. After identifying these genes, the next step is to insert them
into the plant's code to create new strains. |
| ABC Science / Nature
Feb 11, 2010 |
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| World's most precise clock created |
The new record-holder for the most precise timekeeper could tick off the
13.7-billion-year age of the universe to within 4 seconds.
The optical clock monitors the oscillation of a trapped atom of
aluminium-27. It is more than twice as precise as an earlier version,
reported in 2008, and was built at the National Institute of Standards
and Technology in Boulder, Colorado.
The second is currently defined by caesium atomic clocks, but optical
clocks promise higher precision because their atoms oscillate at the
frequencies of light rather than in the microwave band, so they can
slice time into smaller intervals. Such clocks could help spot tiny
changes in physical constants over time. |
| New Scientist / arxiv.org
Feb 08, 2010 |
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