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A.
An Air Flight of the Future
Narrator: This is Science Today. Imagine flying
anywhere on the planet from the continental U.S. in
just two hours or less? Although this concept is still
a dream for many international travelers, such an
aircraft has already been designed by aerospace engineers
at the Lawrence Livermore National Laboratory. Preston
Carter is the mastermind behind HyperSoar - and says
this futuristic, hypersonic aircraft can fly ten times
the speed of sound.
Carter: But it does it in an unusual way. It
takes off like a regular airplane, accelerates up
to ten times the speed of sound and at a hundred and
fifteen thousand feet in altitude, it shuts off its
engines. It will coast out of the atmosphere and then
it starts skipping on the atmosphere.
Narrator: Carter likens this to a rock skipping
across water - the only difference is, unlike a rock,
HyperSoar's skipping motion will not damp out. To
a person aboard, the sensation would be like being
on a swing - only much slower. A prototype will be
built within the next five years, but Carter says
it'll be a while before passengers board HyperSoar.
Carter: I certainly hope that it will happen
in my lifetime and it certainly will happen in my
kid's lifetime.
Narrator: For Science Today, I'm Larissa Branin.
B.
A Better View of Brain Development
Narrator: This is Science Today. Magnetic resonance
imaging, or MRI, has given researchers the ability
to non-invasively study the brain and provide insight
into normal and abnormal development. Dr. Jim Barkovich,
a neurology specialist at the University of California,
San Francisco, says in the last few years, researchers
have been doing more MR imaging of fetal brains.
Barkovich: Why do we do this? We do it because
maybe someone has done a screening ultrasound and
seen something that looked a little bit suspicious
or didn't look quite right and we can get a much better
look at the brain using magnetic resonance imaging.
Narrator: These images are enhanced by placing
coils on the surface of the head, which give researchers
better resolution.
Barkovich: So by using this technology developed
here at UCSF, we can go from seeing the brain pretty
well, to seeing very clear, high resolution images
of the brain that help us to spot these disorders
of brain formation.
Narrator: For Science Today, I'm Larissa Branin.
C.
New Findings about Asteroids
Narrator: This is Science Today. To better
understand asteroids, scientists must have some idea
about their basic composition and structure. Mark
Hammergren, a planetary scientist at the Lawrence
Livermore National Laboratory, has recently discovered
that very elongated asteroids are weaker in centrifugal
force than circular ones. This finding supports a
theory that most asteroids are not solid chunks of
rock, as formerly thought - but rather loosely held
piles of rubble.
Hammergren: It's a theory that's growing in
popularity among asteroid researchers - that asteroids
could be rubble piles, that they might be held together
- not by material strength, but only by gravity.
Narrator: This can give researchers an idea
of how asteroids have changed since the formation
of the solar system over four and a half billion years
ago.
Hammergren: And also it helps us figure out
how we're going to deal with these things if one ever
happens to come towards the Earth because how you
deal with a solid object is different than how you
deal with a loosely-held pile of rubble.
Narrator: For Science Today, I'm Larissa Branin.
D.
Who's at Risk of Kidney Disease?
Narrator: This is Science Today. Our kidneys
are responsible for a number of different functions,
but two of the main ones are regulating body fluids
and processing toxins. When these crucial functions
completely fail or dwindle to less than 10% of normal
capacity, end stage renal disease results and dialysis
is needed. Kirsten Johansen, a dialysis specialist
at the University of California, San Francisco, says
currently, the majority of people with kidney disease
are those with diabetes or hypertension.
Johansen: Those are very common diseases and
of course, not everyone who has diabetes or hypertension
ends up on dialysis. It's a small fraction of those
people and probably genetics mediates at least some
of that.
Narrator: But of the estimated 300 thousand
patients on dialysis, about twenty-five to thirty
percent do have diabetes or hypertension.
Johansen: And that's been increasing now that
people with diabetes are able to live longer than
they were in the past with better treatments for their
heart disease, better treatments for their diabetes
and similarly with hypertension, people are living
long enough to develop kidney disease from those things.
Narrator: For Science Today, I'm Larissa Branin.
E.
Several Risk Factors Linked to a Common Cancer
Narrator: This is Science Today. Although there's
a lack of known risk factors for non-Hodgkin's lymphoma,
each year it's increasing in both American men and
women at a faster rate than all other cancers except
melanoma. But a new study is giving researchers more
insight into this disease. Epidemiologist Elizabeth
Holly of the University of California, San Francisco,
found several factors associated with an increased
risk.
Holly: Among those were taking ulcer medications
- it's probably more likely to be related to the ulcer
condition. Also, having had a splenectomy many years
prior to the diagnosis of lymphoma was associated
with a five-fold increased risk. Also having had polio
many years before was associated with nearly a three-fold
increased risk.
Narrator: Another risk factor is being overweight.
Holly: In America now with more than half of
the population being overweight, this could have an
important impact.
Narrator: For Science Today, I'm Larissa Branin.
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