OF
NOTE
EARTH SCIENCE
Magma heats up
as it crystallizes
Molten rock moving up through a volcano’s
plumbing prior to an eruption can heat up
substantially, an unexpected finding that
could affect scientists’ models of the eruption process.
Magma crystallizes as it slowly loses heat
to the environment, a process in which
minerals with the highest
melting points are the
first to solidify. However,
magma can also crystallize when volatile substances such as water and
carbon dioxide bubble out
suddenly, causing pressure within the lava to
drop, says Kathy Cashman, a volcanologist at the
University of Oregon in
Eugene. When pressure
drops slowly, the first minerals to solidify give up
large amounts of heat that
warms the remaining
molten rock, Cashman and her colleagues
report in the Sept. 7 Nature.
For their study, the researchers chemically analyzed crystals that had formed
within lava that erupted from Mount St.
Helens between 1980 and 1982 and from
Shiveluch, a Russian volcano, in 2001 and
2002.
Molten rock that had risen to Earth’s surface in those volcanoes over the course of
weeks or months heated up by as much as
100°C during its journey, the team’s analysis suggests. That degree of warming can
alter several physical properties of molten
rock, especially its viscosity. Understanding
such changes may enable scientists to better predict the timing and violence of future
volcanic eruptions, says Cashman. —S. P.
When chemists synthesize compounds,
they often add a protective group of atoms
to a specific site on a molecule to prevent
that site from reacting in subsequent
steps. For example, a silicon-based group
is added to an alcohol site in many syn-theses of organic molecules, says Marc L.
Snapper of Boston College.
However, protecting an alcohol site in
this manner previously required up to
seven chemical steps, he notes. To expedite the process, Snapper, Amir H. Hov-eyda, and their Boston College coworkers
searched for a small molecule that could
catalyze that addition in a single step.
Furthermore, chemists often want to
synthesize one of two possible mirror-
image forms, or chiral molecules. The
function of some molecules depends on
its mirror-image form.
Snapper and his col-
leagues used their cata-
lyst, which is chiral, on a
compound with two alco-
hol groups in symmetri-
cal positions on the mol-
ecule. The catalyst added
the protecting group to
only one position, making
the compound also chiral.
The researchers report in
the Sept. 7 Nature that
the reaction makes 98
percent of one mirror-
image form and only 2
percent of the other.
The researchers are now working to
improve the speed of the reaction and apply
the catalyst to compounds with different
numbers of alcohol groups. —A.C.
nant women. Of these, 72 had developed
preeclampsia late in their pregnancies.
Those women had blood concentrations
of soluble endoglin that were nearly double those found in women who had
uncomplicated pregnancies. The warning
sign appeared 2 to 3 months before
preeclampsia struck, the researchers
report in the Sept. 7 New England Journal of Medicine.
The work adds soluble endoglin to a
growing list of proteins that, in aberrant
supply, signal an increased risk of
preeclampsia (SN: 2/14/04, p. 100). For
example, pregnant women who are destined to develop preeclampsia often have
too little placental growth factor in their
blood and too much of a protein that regulates blood vessel growth (SN: 5/10/03,
p. 293; 3/8/03, p. 147).
In fact, Levine and his colleagues found
that using measurements of soluble
endoglin and the ratio of these two other
compounds to each other provided even
better predictions of preeclampsia than
either test did on its own.
The next step is to combine these measurements into a reliable test for preeclampsia that yields few false-positive readings,
says Levine. —N. S.
GROWTH RINGS Chemical
analyses of layered crystals in
congealed lava indicate that
some magma gets hotter as it
ascends through a volcano.
SCIENCE & SOCIETY
Women: Where
are your patents?
BIOMEDICINE
Forewarning of
preeclampsia
CHEMISTRY
Better protection
J. BLUNDY AND CASHMAN
A new molecular catalyst shortens a widely
used reaction into a one-step process, with
a bonus: It makes the reaction’s products
into one of two possible mirror-image
forms.
Scientists have found an early warning sign
of preeclampsia, a pregnancy complication
marked by high blood pressure. Pregnant
women with too much of a protein called
soluble endoglin in their blood have a
heightened risk of preeclampsia, the
researchers say.
Endoglin normally sits on the surface of
blood vessels, where it plays a role in vessel
dilation and facilitates blood flow. But
endoglin can escape these moorings and
dissolve in the blood.
Epidemiologist Richard J. Levine of the
National Institute of Child Health and
Human Development in Bethesda, Md.,
and his colleagues tested stored second-trimester blood samples from 552 preg-
While compiling a database of life scientists participating in biotech start-up companies since the 1970s, Toby E. Stuart of
Harvard Business School in Boston gave
a start when he ran across the name
Nancy. It stood out, the sociologist says,
because it was the only obviously female
name among the first 70 entries. They discovery prompted him and two of his colleagues at other business schools to investigate additional gender gaps among life
scientists in academia. The researchers
found a doozie: men and women with
potentially money making patents.
The trio randomly chose 4,200 scientists
from the life science fields most likely to
foster commercial spin-offs and then examined 30 years of patent records.
In the Aug. 4 Science, Stuart and his
team report finding that 5.65 percent of
the women in this group were patent holders versus 13 percent of men. Because
“women faculty members patent at about
40 percent of the rate of men,” many
women lost out on significant extra
income from royalties and entrepreneurial opportunities, says Stuart.
