22 NEWS Health & Science
Stardust in your teeth
Astronomers have detected signs of fluo-
rine, an element found in human bones and
teeth as fluoride, in a galaxy more than
12 billion light-years away. Virtually all the
elements in the universe were forged inside
the cores of stars and then released in stel-
lar explosions. But astronomers have long
been uncertain about which stars produced
most of the fluorine in the universe. Using
data from the Atacama Large Millimeter/
submillimeter Array of telescopes in Chile,
they have now detected the element, in the
form of hydrogen fluoride, in gas clouds in
the NGP-190387 galaxy. The light from that
galaxy has traveled over 12 billion years to
Earth, so astronomers view the galaxy as it
appeared when the universe was 1.4 billion
years old—about 10 percent of its current
age. The telescope data indicated that the
flourine was released by Wolf- Rayets: mas-
sive stars that survive only a few million
years before exploding. “We all know about
fluorine because the toothpaste we use every
day contains it in the form of fluoride,”
lead author Maxi mil ien Franco, from the
Uni versity of Hert ford shire in the U.K., tells
CNN.com. Wolf- Rayets “help us, in a way,
to maintain good dental health.”
Concussions and hearing
A concussion is usually associated with
headaches, nausea, dizziness, and confu-
sion. Now new research suggests another
symptom should be added to this list: an
inability to understand speech in a noisy
room. “Making sense of sound is one of the
hardest jobs that we ask our brains to do,”
says Nina Kraus, from North wes tern Uni-
ver sity. “So, you can imagine that a concus-
sion, getting hit in the head, really does dis-
rupt sound processing.” Kraus is studying
500 elite college athletes to see how blows
to the head affect hearing. She says those
who sustain a concussion typically have no
problem detecting faint sounds but struggle
to make out speech when it’s embedded in
background noise. That finding echoes sep-
arate research on military personnel who
survived concussion- causing bomb blasts
in Afghan i stan and Iraq, reports NPR.org.
Researchers observed that the veterans’
hearing appears perfectly fine in tests, but
that these vets cannot process what they’re
actually hearing. Whereas most of the
athletes in Kraus’ study recovered their abil-
ity to process sound after a week or two,
some veterans still have auditory issues
more than a decade after being caught up
in a bomb blast.When Antarctica was on fire
The Cretaceous period, which lasted from
145 million to 66 million years ago, is
known by researchers as the “super fire
world.” Massive wildfires raged across
much of the planet, but not, researchers
assumed, in Ant arc tica. Now a new study
suggests that the southernmost continent
was also scorched by these blazes, reports
The New York Times. An analysis of fos-
silized charcoal extracted from sediment
on Ant arc tica’s Ross Island found that
these ancient hunks of carbon had once
been plants. Specifically, they were an
ancient family of conifers called Arau car-
ia ceae, suggesting that paleofires were a
feature of prehistoric life in Ant arc tica.
The finding is important because it will
help further scientists’ understanding of
another era marked by rapid changes in
the climate—the one we’re living through.
“The more we know about the past and
the linkages between the ecosystem and
climate,” says Cathy Whit lock of Mon tana
State Uni ver sity, who was not involved in
the study, “the better prepared we are for
the future.”MediaBakery,^
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O,^AlamyFlourine has been detected in a distant galaxy.The biggest whales scarf far more food
than scientists had previously thought, a
new study has found—a gargantuan 10
to 20 tons a day, the calorie equivalent
of 80,000 Big Macs. Researchers wanted
to find out how much the giant mam-
mals eat because their iron-rich poop is a
crucial component of ocean ecosystems.
They fitted 321 baleen whales—a category
that includes blue whales, gray whales,
and humpback whales—with
devices that
could track
how often they
lunged for food.
They then useddrone- mounted cameras and boat- fitted
sonar sensors to measure the size of their
meals. Overall, the colossal mammals
ate about three times more than previ-
ous research suggested. Different whales
took in different amounts: The North
Pacific blue whale, which can weigh up to
100,000 pounds, ate some 5,840 tons of
krill a year, while the North Atlantic right
whale gobbled 1,825 tons of zooplankton.
“Whales are acting as mobile krill pro-
cessing plants,” co- author
Matthew Savoca,
tells USA Today,
“eating and
pooping far from
land in a system that is iron-
limited in many places.”Whales’ jumbo appetites
A humpback whaleIf you want a healthy heart, make sure you
go to bed between 10 and 11 p.m. That’s the
conclusion of a new study which found that
people who hit the hay during that narrow
window have lower rates of cardiovascular
disease than those with earlier or later
bedtimes. The study looked at some 88,000
adults, with an average age of 61, who for
a week wore devices that measured their
falling- asleep and waking-up times, reports
The Wash ing ton Post. Researchers then
looked at how many of these people went
on to suffer cardiovascular issues—such as
a stroke, heart attack, or heart failure—over
a follow-up period averaging about sixyears. Those who went to bed between
10 and 11 p.m. had the lowest rates of car-
diovascular disease. Compared with that
group, study participants who hit the sack
between 11 and 12 p.m. had a 12 percent
higher risk of developing cardiovascular
disease, while those bedding down after
midnight had a 25 percent higher risk. Doz-
ing off before 10 p.m. was associated with
a 24 percent increased risk. The research-
ers say the most likely explanation is that
bedtimes affect the body’s internal clock,
or circadian rhythm, which helps regulate
physical and mental functioning. “We’ve
evolved to be daytime creatures that don’tlive at night,” says co- author David Plans,
head of research at the Lon don health-tech
company Huma. “The circadian clock has a
much stronger influence on overall health
than we thought.”The ideal bedtime for a healthy heart
Try to fall asleep between 10 and 11 p.m.