Science News - February 12, 2011

Scientific Observations

“The process of learning what string theory means
has a long way still to go. One of the reasons that it is,
I think, an exciting topic for today’s students to work
on is precisely that so much isn’t understood. It’s
sometimes framed as a criticism, that string theorists
don’t really understand their theory. That’s true, but if
we understood it, it might be finished. The fact that so
little is understood and that such relatively small pieces
are actually such big discoveries in their own right is part of what makes it
exciting. And there’s a lot still more to do.” — PHYSICIST EDWARD WITTEN OF THE INSTITUTE
FOR ADVANCED STUDY IN PRINCETON, N.J., IN HIS ACCEPTANCE LECTURE FOR THE 2010 ISAAC NEWTON MEDAL

SN Online

www.sciencenews.org

SCIENCE & THE PUBLIC BLOG Too much light before sleep could stress the body. Read “Night owls may want to dim their lights.”

LIFE

Spring thistles may inspire bird courtship. See “ Songbird’s testosterone surges at sight of thistle blooms.”

Science Past | FROM THE ISSUE OF FEBRUARY 11, 1961

RELIEVE ARTHRITIC JOINTS — Chronically inflamed
arthritic joints can be relieved, but not cured, by injecting
cortisone-related steroids, or hormone drugs, directly into
the joint. Repeated injections, up to 142
times in one case, had no apparently
harmful effect, three doctors report in the
Bulletin of Rheumatic Diseases, Jan., 1961.
Some 4,000 patients at the University of
Pennsylvania Arthritis Clinic, Philadelphia,
received more than 100,000 injections
during a ten-year period.... Reduction in swelling and
relief of pain was found in 90%. The physicians state that
relief varies and is often temporary. Because the treatment
can be repeated in long-term cases of the most serious
types of arthritis ... however, it is especially valuable.

Science Future

February 15 Discuss controversy over nonnative species at the University of Minnesota’s natural history museum happy hour. See www.bellmuseum.org

February 17 Author Sam Kean regales New York City with tales of the periodic table. Go to www.nyas.org

ATOM & COSMOS Lightning storms regularly shoot antimatter into space. Read “Today’s weather: thunder and antimatter beams.”

February 17 Cybersecurity experts address hazards of the digital age at Chicago’s Northwestern University. See http://c2st.org

BODY & BRAIN Metal tongue studs beget infections and chipped teeth. See “Tongue piercings worse with metal.”

How Bizarre

When swimming near an air-liquid boundary, a bacterium
moves as if it’s cruising alongside a mirror image near no
boundaries. A corkscrewlike flagellum propels the microbe,
but comes with bad steering. In open water, poor steerage
isn’t a problem because the spinning flagellum creates a
flow in the surrounding fluid that directs a bacterium along
a straight line. But near a boundary, such as a solid surface,
this flow is distorted and makes the microbe loop-the-loop.
Knowing solid surfaces cause clockwise looping, Roberto
Di Leonardo of the Sapienza University of Rome and his
team tested E. coli’s moves near an air-liquid interface.
They report online January 19 in Physical Review Letters
that the bacterium moves
counterclockwise, as
though navigating a flow
created by it and a mir-
ror image as they swim
through open water.