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A.
Save the Dirt: Rare and Endangered Soils
Narrator:
This is Science Today. Certain soils in the United
States, like certain plants and animals, are becoming
increasingly rare, with some at risk of becoming
extinct. Ronald Amundson, a professor of ecosystem
sciences at the University of California, Berkeley,
explains.
Amundson:
We found that out of these nearly 20,000 different
soil types, there's roughly 30 or 40 that we would
consider more or less extinct. They've all been
either converted to farming or urbanization.
Narrator:
In their study, Amundson and his group used a unique
map of soil diversity that depicts rare and endangered
soils.
Amundson:
We produced a map of the United States to show sort
of the hot spots of endangered soils lie. In the
Great Plains, the Cornbelt, the Great Valley of
California were all areas where red colors basically
dominated the map, as one might expect, due to the
intensity of land use in these areas.
Narrator:
For Science Today, I'm Larissa Branin.
B.
New Insight in to Why We Crave Comfort Foods When
Stressed
Narrator:
This is Science Today. If you're chronically stressed
out, chances are you will reach for chocolate or other
comfort foods. Mary Dallman, a physiology professor
at the University of California, San Francisco, found
that when chronically stressed, stress hormones in
rats prompted them to engage in pleasure-seeking behaviors
- like eating high-energy foods.
Dallman:
They drank more sucrose, but they ate less chow so
that their caloric intake wasn't any more, but their
sucrose intake was and the high sucrose in any sort
of animal helps to put on abdominal fat.
Narrator:
Evolutionarily speaking, Dallman says this kind of
weight gain when stressed makes sense. But in the
long-term, this kind of fat is not good.
Dallman:
This particular fat mass is associated strongly with
bad outcome with time. Cardiovascular disease, stroke
and Type 2 diabetes - and these are major problems
in our society and perhaps some of that is a consequence
of this comfort food notion - which is still a hypothesis.
Narrator:
For Science Today, I'm Larissa Branin.
C.
Promoting
Combined Heat and Power Among Small Businesses
Narrator:
This is Science Today. What if all the mini-malls
in the United States joined together to dramatically
improve our country's energy situation? It's visions
like this that have inspired a collaboration between
The U.S. Department of Energy and three California
universities that will promote the use of Combined
Heat and Power among small businesses. Professor Daniel
Kammen of the University of California, Berkeley,
explains.
Kammen:
Usually the issue is that there is a mini-mall somewhere
or a neighborhood that has a little power plant that
they're operating already and there is waste heat
that is not being captured, but you can also find
ways to capture that heat.
Narrator:
The Combined Heat and Power mandate will educate local
industries on how to capture waste heat and how to
install cleaner burning, higher efficiency alternatives.
Kammen:
If we could for example convert a quarter of the businesses
in California and the Western states that we are responsible
for in the Center, to some version of Combined Heat
and Power, that's a potential huge savings for the
country in terms of energy, for the businesses in
terms of power and then very directly a big savings
in the amount of green house gases that get emitted
from these operations.
Narrator:
For Science Today, I'm Larissa Branin.
D.
Old Mines are a Major Source of Mercury Contamination
Narrator:
This is Science Today. Mercury has recently been recognized
as a major environmental concern because concentrations
of mercury once considered safe are now known to cause
neurological damage. Russ Flegal, an environmental
toxicologist at the University of California, Santa
Cruz, says one of the reasons controlling levels of
mercury is so difficult is because mercury is so volatile
as a gas.
Flegal:
Large amounts of mercury are found in fossil fuel
products so when they burn coal, that puts a lot of
mercury into the atmosphere. So recently in the United
States, they've gone at great lengths to control mercury
emissions from coal production.
Narrator:
Flegal says it used to be thought that simply plugging
up openings to abandoned mercury mines could do this.
Flegal:
But when they process mercury, they take the
ores out and they heat them - they volatize whatever
mercury they can and they push the slag rock over
the hill, and that slag is essentially pure mercury
sulfite anyway and so when it's exposed to the environment,
it continues to release mercury.
Narrator:
For Science Today, I'm Larissa Branin.
E.
Acute Seizures Demand Medical Attention
Narrator:
This is Science Today. Seizures occur when the brain's
neurons misfire, frequently causing abnormal movement
and behavior in the human body. When a seizure happens,
the brain can often return to its normal functions
rather quickly - usually in less than a minute. But
as Doctor Brian Alldredge, a neurology professor at
the University of California at San Francisco points
out, sometimes the brain is unable to respond.
Alldredge:
In some cases, either when people have epilepsy or
people have an insult to the brain that causes their
first seizure in their lifetime, the normal brain
functions that stop seizures cannot be present, or
the extent of the injury is so big that the brain
can't stop the injury by itself.
Narrator:
If
a seizure lasts for much longer than a minute, Alldredge
says the situation can be life threatening.
Alldredge:
And when it starts to last three, four, five minutes
and longer than that, it becomes what we call an acute
seizure or an emergent seizure - something that requires
emergency medical attention.
Narrator:
For Science Today, I'm Larissa Branin.
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