April 17, 2002
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Contents of this News Tip:
Rivers 'Exhaling' Millions of Tons More CO2 Than Thought
U.S. and Brazilian researchers say the amount of carbon
dioxide rising from streams, rivers and flooded areas
of the world's tropical forests is triple that of
some currently accepted estimates, meaning such forests
are not the carbon sponges some scientists believe.
The new total of 900 million metric tons (about two
trillion pounds) of carbon given off globally by tropical-forest
waterways is comparable to nearly a fifth of the carbon
dioxide generated each year by human activities such
as deforestation and burning fossil fuels.
The total matches the amount modelers speculated was
missing from tropical forests when they tallied the
worldwide movement of carbon, says Jeffrey Richey,
a National Science Foundation (NSF)-supported oceanographer
at the University of Washington and lead author of
the findings published in the April 11 issue of Nature.
The scientists correlated river measurements from 13
NSF and Brazillian government sponsored expeditions
to the Amazon in the 1980s and 1990s with radar imagery
that NASA recently released.
In global-carbon models, CO2 levels have been lower
than researchers expected when they used pre-existing
numbers from efforts to directly measure carbon dioxide
in the air in, and just above, tropical forests. In
contrast, Richey and his colleages found that by adding
the contributions from waterways, the amount of carbon
dioxide is actually about even; about as much CO2
absorbed as is released by tropical forests.
"The land-water connection appears to be far more important
than anyone thought," Richey said. "If you want to
know where carbon from today's tropical forests goes,
look a thousand kilometers downstream in 20 or 30
years." [Cheryl Dybas]
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Life" Discovery May Offer Clues for Treating Genetic
For nearly half a century, molecular biologists have
sought to solve the mystery of protein synthesis and
the role of ribosomes -- the small molecules in cells
that craft proteins. Now, UCLA molecular biologists
James Lake and Anne Simonson, with funding from NSF,
believe they may have discovered how the ribosomal
"factory of life" works.
In our cells, translation is the process that turns
genes into proteins. Scientists have not understood
how this critical process works, but have known that
it has three phases; initiation, elongation and termination.
Elongation is the most critical, although a number
of current antibiotics work at the initiation phase.
"Elongation is the heart of protein synthesis," says
Lake, "the phase in which the ribosome adds amino
acids, sometimes hundreds of them." Lake and Simonson's
work sheds light on the molecular details of elongation,
including the location and movement of more than 10,000
atoms. With the new findings, it may be possible to
modify parts of the translation process to suppress
lethal mutations and design new proteins to counteract
the defects that cause hundreds of diseases.
Each of our cells has more than 100,000 ribosomes,
and uncovering their role -- what Lake calls the "puzzle
of life" -- requires a much greater understanding
than the broad outlines scientists have traditionally
"The ribosome is like a computer-driven protein factory
that has been cloaked in secrecy," says Lake. "We
knew the shape of the factory, and we could see the
trucks going in, but we couldn't peer beyond the factory
gate. We knew the names of the employees, but we didn't
know what they did."
"Now we have a hypothesis of how the employees move
in and out of different rooms to get their work done,
and even what they have for lunch." [Cheryl Dybas]
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Awards Presented for Excellence in Math and Science
President Bush named 194 teachers from around the country
to receive the 2001 Presidential Awards for Excellence
in Mathematics and Science Teaching (PAEMST). The
White House program, administered by NSF, bestows
this nation's highest honor on mathematics and science
teachers of kindergarten through grade 12.
The Presidential awardees - who represent every state,
the District of Columbia, U.S. territories, and the
U.S. Department of Defense schools - were selected
from more than 600 nominees. After an initial selection
process at the state or territorial level, a national
panel of distinguished scientists, mathematicians
and educators recommended finalists for the Presidential
award - one elementary and one secondary teacher each
from both mathematics and science - from each state
Every 2001 Presidential awardee receives a $7,500 grant
for their school. The recipients claimed their awards
in Washington on March 20.
For a complete listing of this year's awardees, or
more information on how to apply for a Presidential
Award for Excellence in Mathematics and Science Teaching,
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