A cheap alternative
to the lasers used in surgery has been devised using an energy
source that is free and abundant - sunshine. The working prototype
made by Israeli physicists concentrates sunlight down a fibre-optic
cable to provide a tool for surgeons. Jeffrey Gordon and his colleagues
at Ben-Gurion University in Israel hope it might one day replace
the expensive surgical lasers used in operations such as the destruction
of tumours in the liver.
The Information
Age rides on beams of carefully controlled light. Because lasers
form the arteries of modern communications networks, dexterous
manipulation of light underpins the two definitive technologies
of our times: telecommunications and the Internet. Now researchers
at Harvard University have developed a new way of steering and
manipulating light beams using droplets of liquid crystals.
Like poker chips,
lasers may someday be molded out of plastic by the millions. A
new laser-making method takes a major step in that direction, its
Austrian developers say. Lasers are devices that emit a coherent
beam of light of a single wavelength. Their prices have been coming
down over the years, but dirt cheap plastic ones could serve as
the heart of mass-produced biomedical and environmental sensors
and optical-telecommunications networks, the researchers say. What's
more, unlike the lasers currently available, plastic ones could
be flexible.
Astronomers
have found the first direct evidence that dark energy - a sort
of push balancing gravity's pull - pervades the Universe. Ryan
Scranton of the University of Pittsburgh in Pennsylvania and
his colleagues have detected a fingerprint of dark energy in
the afterglow of the Big Bang, radiation called the cosmic
microwave background (CMB). The CMB is slightly hotter where
there are more galaxies. Dark energy is the only explanation,
the researchers argue.
A new research
paper in the journal Science describes ocean mixing in unprecedented
detail. Using an array of technologies and instruments, scientists
in the Hawaii Ocean-Mixing Experiment (HOME), a nearly $18 million
National Science Foundation-sponsored project focused on pinpointing,
dissecting, and analyzing ocean mixing, captured intriguing phenomena
including undersea waves that spanned nearly 1,000 feet.
Some people
are hit harder by stressful life events than others. Variation
in a single gene may explain why some people weather stressful
events while others are plunged into depression, say scientists.
People carrying two short forms of the 5-HTT gene had a 43%
chance of becoming clinically depressed after four or more
stressful events experienced between the ages of 21 and 26.
This compares with 17% of those with two long ones.
With a grant
from the National Institutes of Health, a research team in the
Laboratory for Neuroengineering at the Georgia Institute of Technology
is connecting laboratory cultures containing living neurons to
computers in order to create a simulated animal. The Hybrot, a
small robot that moves about using the brain signals of a rat,
is the first robotic device whose movements are controlled by a
network of cultured neuron cells.
Scientific journals
are abuzz with news of a major development in nanotechnology at
the University of Texas at Dallas. Researchers have uncovered a
reliable method for making tiny, super-tough fibers that could
dramatically change clothes, cars and even space travel.
Smaller than
bacteria, some of them look like microscopic spacecraft. You can
find them almost anywhere: under a rosebush or miles out to sea.
These strange entities are bacteriophages, viruses that prey upon
bacteria, and there's a staggering number of them. A pinch of soil
or drop of seawater, for example, contains many millions of bacteriophages.
Long before
our Sun and Earth ever existed, a Jupiter-sized planet formed
around a sun-like star. Now, 13 billion years later, NASA's
Hubble Space Telescope has precisely measured the mass of this
farthest and oldest known planet. The ancient planet has had
a remarkable history because it has wound up in an unlikely,
rough neighborhood. It orbits a peculiar pair of burned-out
stars in the crowded core of a globular star cluster.
Astronomers have
used the two 10-meter Keck Telescopes in Hawaii together as a single
unit to gain high-resolution data about a possible solar system
being born 450 light-years away. Like many newborn stars in the
Taurus Dark Cloud, DG Tauri shows the infrared signs of having
a protoplanetary disk of dust and gas around it. A collaboration
of 63 researchers led by Rachel Akeson (Caltech) used the Keck
Interferometer, as the combination of the two telescopes is called,
to resolve the star's infrared profile.
A UC Irvine study
has revealed a new class of cosmic particles that may shed light
on the composition of dark matter in the universe. These particles,
called superweakly interacting massive particles, or superWIMPs,
may constitute the invisible matter that makes up as much as one-quarter
of the universe’s mass.
