Science News - July 2, 2011

Say What?
capillary state \KA-pih-LEHR-ee stayt\
n. In a mixture of solid particles and two
unblendable liquids, a state in which the
particles huddle in clumps surrounding
droplets of the liquid that wets the solid
particles less. These clumps allow what
was runny goo to become a gel after some
stirring, Erin Koos and Norbert Willenbacher of the Karlsruhe Institute of
Technology in Germany reported in February in Science. Previous work has
shown similar goo-to-gel transitions, but in those cases particles formed
networks instead of clumps and were connected by the liquid that wetted
them more. Gel-able suspensions, like the oil–water–glass bead mixture
shown (yellow dye marks the water), will allow scientists to tune fluids’ flow
properties and build lightweight porous ceramics.

SN Online

www.sciencenews.org

SCIENCE & THE PUBLIC BLOG Sound science is lacking for many alternative remedies. See “Traditional Chinese medicine: Big questions.”

LIFE Microbes flourish, maybe at the expense of fish, during jellyfish blooms. See “Marine microbes fritter away jelly bonus.” Larger broods bring more stress for a tree swallow mom (below, with mate), but also more fledglings. See “Stressed bird moms.”

Science Past | FROM THE ISSUE OF JULY 1, 1961

WINTERGREEN VS. ALMOND IN ODOR PENETRATION TES T — Different chemicals produce different odors because vibrations within the molecules are different.

This is the theory of Dr. R.H. Wright of
the British Columbia Research Council
in Vancouver, Canada. He compared
nitrobenzene, which has an almond
smell, and methyl salicylate, which smells
like wintergreen. Both these substances
are much alike so far as vibrations are
concerned, except that wintergreen has two additional
frequencies that are missing in nitrobenzene.… In experi-
ments with 12 volunteer sniffers, Dr. Wright showed that
the wintergreen odor masked the almond smell about ten
times more easily than almond masked wintergreen. The
effect is not large … but it is distinct and in the direction
predicted by the vibrational theory of odor.

The (-est)

Excavations in northern Chile have uncovered the oldest known mine in the Americas. New World settlers intentionally dug a pit and removed chunks of iron oxide at the coastal site between 12,000 and 10,500 years ago, Chilean and French researchers reported in the June Current Anthropology. Past work has documented the use of iron oxide as a pigment in the Americas around that time, but the new mine is at least 6,000 years older than previous dated evidence for mining in the Americas. Because the mining was intensive and technically skilled, the coastal area’s early settlers probably carried the tradition with them from elsewhere, the authors propose.

Science Future

July 7

Be mesmerized by the color red and how it is made for pigments and paints, at San Francisco’s Exploratorium. Ages 18 and up. See www.exploratorium.edu/ afterdark

July 18

In Washington, D.C., a Smithsonian science historian describes ancient apothecaries and their brews. See www.residentassociates.org

MAT TER & ENERGY Researchers turn virtual particles into real photons. Read “Light created from the void.”

Science Stats | SWIM WI TH THE FISHES

Indo-Paci;c lion;shes have invaded the Caribbean and the western Atlantic (below) in the last decade, data from the U.S. Geological Survey show. More than 30 nonnative marine ;sh species have appeared off Florida’s coast, but lion;shes are the ;rst to establish themselves.