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3D structure of the influenza virus. Illustration: Hector Aiza, Flickr.com
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Issue no. 31, 2009
Published: Sep 18, 2009 |
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 Could we create quantum creatures in the lab? | | Super-dense data stores cool down | | When opposite charges repel | | Liquid specs a bold vision for world's poor | | Virtual maps for the blind | | Toward the design of greener consumer products | | Scientists create digital models of World Heritage sites |
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| Could we create quantum creatures in the lab? |
In quantum theory, a single object can be doing two different things at
once. This 'superposition' is a delicate state, destroyed by any contact
with the outside world. The largest objects that have been superposed so
far are molecules. It is hard to put a much larger object such as a cat
or a human into a superposition because air molecules and photons are
always bouncing off it. Making a living thing do two things at once
could answer fundamental questions about the nature of quantum theory.
It might be possible with a small life form, according to researchers at
the Max Planck Institute for Quantum Optics in Garching, Germany. They
hope to prove the concept with the flu virus, which exhibits some
properties of life, because it can survive in a vacuum - solving the
problem of pesky air molecules.
Their scheme would use two laser beams, whose light exerts a gentle
force on matter. Where the two beams cross they form an 'optical cavity'
holding the virus in place. By adjusting the frequency of the beams, the
laser photons can be made to absorb the vibration energy of the trapped
virus about its centre of mass until it is slowed to its lowest possible
energy state. In this 'ground state' the virus is ready to go into a
superposition.
Sending a laser photon towards the trap should do the trick. Since a
photon is a quantum entity it has more than one option open to it. Thus
it will be both reflected and transmitted at the trap, putting it into a
superposition. By impinging on the virus, it forces it into a super-
position of both its ground state and next vibrational energy state. |
| New Scientist
Sep 15, 2009 |
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| Super-dense data stores cool down |
Engineers in Korea have created a material that could allow super-dense
'millipede'-style data storage systems to work at room temperature. The
discovery brings the technology closer to commercial reality.
A decade ago, IBM engineers unveiled the ultra-high-density 'millipede'
data storage system. Now more than ever, people who want to store
digital photos and video need this probe storage system - which can cram
a terabit a terabit, or 125 GB, into every square inch - but IBM's and
other systems with similar designs remain frustratingly distant.
Millipede and other similar systems work on a simple principle: an
incredibly sharp needle - the probe - etches data as a series of
nanoscale pits in a tough polymer surface, and the same probe feels for
what's been written to read it back. But to punch a hole in the hard
polymer surface the probe had to be hot enough to make the polymer
temporarily pliable. Raising a probe to the 350 °C necessary for each
digital 1 and 0 to be written makes the system very expensive.
The Korean team has designed a probe storage system that doesn't need
heat to function. Instead, it uses an unusual 'baroplastic' - a hard
polymer that becomes soft when placed under pressure. The Korean team
has shown that the tip of an atomic force microscope (AFM) can etch the
kind of tiny pits that store data in millipede-like systems simply by
pressing on the new material. Lighter pressure can be used to feel for
and read out the pits without altering them. |
| New Scientist / Nature Nanotechnology
Sep 17, 2009 |
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| When opposite charges repel |
Opposites always attract, right? Not quite. A new experiment has shown
that a drop of water with positive electrical charge can be made to
'bounce off' a negatively charged object.
William Ristenpart of the University of California at Davis accidentally
applied a strong electric field to a beaker filled with oil and water.
At first the mixture erupted into a turbulent mess, but as he turned
down the voltage Ristenpart saw droplets of water suspended in the oil
bouncing between the electrode at the top of the beaker and the
oil-water boundary below. The droplets were positively charged, so why
didn't they merge with the negatively charged body of water?
Ristenpart set out to reproduce the happy accident, now filming with an
ultra-high-speed camera. The video shows that when a droplet nears the
water-oil boundary it elongates slightly, forming a tiny bridge.
Ristenpart thinks that positive ions drain out of the droplet and
negative electrons come in through the bridge, so the droplet, now
negatively charged, is drawn up to the positive electrode, where it
regains its original positive charge, and so on. The discovery could
lead to new microfluidic devices and better methods for separating salt
water from crude oil. |
| New Scientist / Nature
Sep 17, 2009 |
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| Liquid specs a bold vision for world's poor |
In the developing world millions of people s don't have access to the
eye glasses they need. But a pair of glasses developed by Joshua Silver
at the University of Oxford, offers an affordable solution. The glasses
can be adjusted to the right strength by the wearer, without the need
for them to visit an optometrist.
Silver has been developing the glasses for over 20 years and continues
to research the technology at the Centre for Vision in the Developing
World (CVDW) at the University of Oxford. About 80% of those who try the
glasses are able to correct their vision.
The lenses consist of clear membranes filled with silicon oil, protected
by plastic discs. The wearer can adjust the amount of oil in the lenses
using a dial fitted to a syringe on the arms of the glasses. Changing
the amount of oil in the lenses changes their curvature, which alters
their strength. When someone has adjusted the lenses to suit their
vision, the lenses are sealed with a valve and the syringes removed,
giving near-instant glasses with no need for an optometrist.
The glasses are currently functional, rather than fashionable, and that
may limit their uptake, but more cosmetic versions are being developed. |
| CNN
Sep 16, 2009 |
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| Virtual maps for the blind |
The blind and visually impaired often rely on others to provide cues and
information on navigating through their environments, which doesn't give
them the tools to venture out on their own. Now researchers at Tel Aviv
University have invented software to help the blind navigate through
unfamiliar places. It is connected to an existing joystick, a 3-D haptic
device, that interfaces with the user through the sense of touch.
People can feel tension beneath their fingertips as a physical sensation
through the joystick as they navigate around a virtual environment which
they cannot see, only feel: the joystick stiffens when the user meets a
virtual wall or barrier. The software can also be programmed to emit
sounds - a cappuccino machine firing up in a virtual café, or phones
ringing when the explorer walks by a reception desk.
Exploring 3D virtual worlds based on maps of real-world environments,
the blind are able to 'feel out' streets, sidewalks and hallways with
the joystick as they move the cursor like a white cane on the computer
screen that they will never see. Before going out alone, the new
solution gives them the control, confidence and ability to explore new
streets making unknown spaces familiar. It allows people who can't see
to make mental maps in their mind. |
| ScienceDaily
Sep 16, 2009 |
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| Toward the design of greener consumer products |
Scientists are reporting development of a new method for screening
molecules and predicting how certain materials, ranging from chemicals
used in carpeting to electronics, will contribute to global warming.
They hope that the results from this study will be used in the design of
more environmentally friendly materials.
In the new study the researchers note that CO2 is the main greenhouse
gas, which traps heat near Earth's surface like the panes of glass in a
greenhouse. However, other gases have the same effect, and in fact are
even more efficient greenhouse gases than CO2. Scientists know that the
molecules in gases differ in their ability to contribute to global
warming. But they know little about the hows and whys - the molecular
basis of those differences.
The scientists analysed more than a dozen molecules involved in global
warming to find out which chemical and physical properties are most
important in determining their inherent radiative efficiency, and thus
possess the largest potential to contribute to global warming. They
found that molecules containing several fluorine atoms tend to be strong
greenhouse gases, compared to molecules containing chlorine and/or
hydrogen. They found for the first time that molecules containing
several fluorine atoms bonded to the same carbon increase their
radiative efficiency in a non-linear fashion. |
| Science Daily / Journal of Physical Chemistry (forthcoming)
Sep 18, 2009 |
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| Scientists create digital models of World Heritage sites |
A team of British scientists is preparing to create a digital model of
Mount Rushmore using laser scanning so that the iconic US monument can
be recreated were it to be damaged. The survey work is part of a project
to accurately record the exact dimensions of 500 of the most famous
World Heritage Sites, including the Acropolis in Athens and the Great
Wall of China.
The joint team, from the Glasgow School of Art and Historic Scotland,
are currently surveying 10 World Heritage Sites in Britain before they
aim their laser beams at Mount Rushmore in South Dakota. There they will
team up with members of the CyArk Foundation, a non-profit organisation
that has identified several 'at risk' World Heritage sites. Mount
Rushmore is on their list because of concerns over deterioration of the
faces of four former presidents on the granite sculpture.
Laser scanning itself is not new but applying the technology to historic
sites or buildings is a new approach. CyArk's goal is to create a huge
database of detailed surveys of sites so that they can be maintained or
even rebuilt should they be damaged by a natural disaster, climate
change or even war. CyArk said the loss of architectural and
archaeological cultural heritage is becoming a crisis of global
proportions with an urgent need for reliable documentation as a key step
to help preserve heritage sites. |
| Reuters
Sep 17, 2009 |
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