22 NEWS Health & Science
Our galaxy’s explosive past
A massive energy flare tore through the
heart of our galaxy some 3.5 million years
ago—a blast so powerful, it could be felt
200,000 light-years away and may have
lasted some 300,000 years. That’s the
conclusion of a new study by researchers
in Australia and the U.S., a finding that, if
confirmed, could upend our understand-
ing of the Milky Way. “We always thought
about our galaxy as an inactive galaxy,”
co-author Magda Guglielmo, from the
University of Sydney, tells USNews.com.
“These new results instead open the pos-
sibility of a complete reinterpretation of its
evolution and nature.” Basing their research
on data from the Hubble Space Telescope,
the astronomers believe the Seyfert flare was
triggered by nuclear activity near Sagittarius
A*, the supermassive black hole at the cen-
ter of the galaxy. The flare, they say, created
two “ionization cones” that ripped through
the Milky Way and left their mark on the
Magellanic Stream—a long trail of gas that
partially circles the galaxy. “The flare must
have been a bit like a lighthouse beam,” says
co-author Joss Bland-Hawthorn. “Imagine
darkness, and then someone switches on a
lighthouse beacon.”
STDs on the rise
The total number of gonorrhea, chlamydia,
and syphilis cases in the U.S. has risen for the
fifth consecutive year, hitting an all-time high.
Cases of primary and secondary syphilis—
the most infectious stages—increased 14 per-
cent year over year, to more than 35,000;
gonorrhea cases rose 5 percent to more
than 580,000; and chlamydia increased
3 percent, to more than 1.7 million. “Not
that long ago, gonorrhea rates were at his-
toric lows, syphilis was close to elimination,
and we were able to point to advances in
STD prevention,” says Gail Bolan from the
Centers for Disease Control and Prevention.
“That progress has since unraveled.” Health
officials say more people are being screened
for STDs, which means that more cases are
being logged. But they also say fewer people
are using condoms, particularly among high-
risk populations such as sexually active high
schoolers and men who have sex with men.
One especially worrying trend, reports CNN
.com, is the rise in congenital syphilis. That
debilitating and deadly infection occurs when
the disease passes from a pregnant mother
to her fetus through the placenta. More than
1,300 infants were born with congenital
syphilis last year; 94 of them died.The pigs that use tools
Researchers have spotted pigs using tools—
a first for this animal, which is known for
its intelligence. Many wild animals, such
as chimpanzees and dolphins, make use
of tools. But until now, neither wild nor
domestic swine have ever been seen doing
the same. That changed when Meredith
Root-Bernstein, an ecologist, observed a
wild pig in a Parisian zoo
picking up a piece of bark
in its mouth and dig-
ging in the dirt with it.
Root-Bernstein hypoth-
esized that the Visayan
warty pig—a critically
endangered species from
the Philippines—was
nest-building, something
the animals do every sixmonths to prepare for the arrival of piglets.
Colleagues who returned to the zoo the
next spring confirmed her theory. Three of
the four pigs in the pen were using tools to
create a homey nest: a pit filled with leaves.
Subsequent visits yielded the same finding.
Root-Bernstein says it isn’t yet clear why the
pigs use tools, given that their snouts appear
better suited for the task. “Learned things
and cultural things work that way,” she tells
NationalGeographic.com. “Maybe it just
feels like the right thing to do.”Health scare of the week
Air pollution and baldness
Exposure to air pollution may increase
your risk of going bald, according to a new
study from South Korea. Airborne pollut-
ants from exhaust pipes and smokestacks
have already been linked to internal health
problems, including cancer, low fertility,
and heart and lung diseases. But this is one
of the first studies to suggest those particles
could also affect the surface of the body.
Researchers exposed human follicle cells to
varying concentrations of dust and diesel
particulate and then measured the levels of
specific proteins in the cells 24 hours later.
They found that exposure to the pollutants
resulted in reduced levels of beta-catenin,
a protein responsible for hair growth.
Furthermore, they found that levels of three
other proteins that drive hair growth and
hair retention decreased with exposure to
the pollutants in a “dose-dependent” man-
ner. The study didn’t examine whether the
link was more pronounced in men or
women, or in certain age groups. Lead
researcher Hyuk Chul Kwok says
more research is needed to confirm
the effect outside the lab, reports The
Independent (U.K.). But for those
particularly worried about losing
their hair, he suggests “limiting time
walking on busy streets, especially
during rush hour.” Juliett
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k^A quadriplegic man in France has been
able to move all four of his paralyzed
limbs, thanks to a pioneering new brain-
controlled body suit. His movement
remains extremely jerky, and the exoskel-
eton is years from being publicly available.
But scientists nevertheless see this as a
major breakthrough in the treatment of
paralysis. The 28-year-old patient, a for-
mer optician identified only as Thibault,
said taking his first steps in the suit felt
like being the “first man on the moon.”
Paralyzed from the shoulders down after
falling from a balcony four years ago,
Thibault had two implants surgicallyplaced on the outer membrane of his brain,
covering the parts that control movement.
Electrodes read his brain signals and send
them to a nearby computer, which almost
instantaneously translates the brain waves
into movement instructions for the exoskel-
eton suit. Thibault spent two years training
the computer program to understand his
thoughts by controlling a character in a
computer simulation, making it walk and
interact with virtual objects. He then moved
on to the exoskeleton, which is suspended
from an overhead harness. Experts say the
technology could eventually pave the way
for mind-controlled wheelchairs and otherdevices to help paraplegics. “This isn’t
about turning man into machine but about
responding to a medical problem,” study
leader Alim Louis Benabid tells Agence
France-Presse. “We’re talking about
‘repaired man,’ not ‘augmented man.’”Paralyzed man walks again with robo-suit
The Milky Way: Not as peaceful as it looksThibault in the brain-controlled exoskeleton