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- A troop of U.S. soldiers advances in
the barren deserts of Iraq when word arrives that the enemy may have released
an invisible cloud of deadly biological agents.
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- Immediately, a soldier launches a 40-pound
remote-controlled plane, which flies miles ahead. When a red light flashes
on the soldier's controls, the troops quickly suit up in gas masks and
protective gear. They pass through the infectious cloud unharmed.
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- While the military has long employed
remote-controlled planes for surveillance purposes and scientists have
developed instruments that can detect biological weapons, a new craft designed
by researchers at the Naval Research Laboratory is the first to combine
the two technologies. The autonomous bacteria-sniffing airplane has been
tested and is now being refined under funding by the Department of Defense.
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- The mobile sensing device "could
warn troops prior to exposure to disseminated biological warfare agents
or ascertain that the destruction of a hostile production facility has
not released bioagents into the environment," wrote NRL research leader,
Frank Ligler, in a recent issue of Environmental Science & Technology.
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- Former Iraq weapons inspector Jonathan
Tucker points out that research into this kind of technology has taken
on greater pertinence as efforts to monitor Iraq's arsenal of weaponry
are repeatedly frustrated.
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- "I think Iraq's use of biological
weapons is a very plausible threat," said Tucker, who is now director
of the Chemical and Biological Weapons Non-Proliferation Project at the
Monterey Institute of International Studies. Tucker adds that because biological
weapons are virtually undetectable, "knowing that you're under attack
is the most critical defense."
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- The NRL model includes a biosensing device
that is mounted on a German model miniplane with a 12-foot wing span. Once
in flight, the sensor can detect up to four biological agents at a time
as the craft makes low sweeps over infected grounds. It then signals to
the operator miles away if it picks up any signs of a biological agent
like the deadly anthrax.
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- The mechanism that makes the technology
unique is an air filtering system which is powered by the velocity of the
plane, and, in turn, feeds the sensing device on board. As the craft flies
between speeds of 35 mph and 80 mph, air is forced into a water-filled
chamber, sending the water into a swirl. The swirling water then picks
up any micro particles from the air including any possible particles of
a biological agent. Every five minutes, this water washes over the biosensor
device, which is made up of four optical fibers, each containing a probe.
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- From this point, the sensor operates
as it would on the ground. The probes of the sensor are coated with antibodies
that attract specific spores of one of four biological agents. More antibodies
are then washed over the sensors and bind to any spores that have attached
themselves to the probe. Once they bind, these antibodies become fluorescent
and transmit light, which is transformed into an electrical signal.
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- The NRL team tested the unit at a desert
test site in Utah and found that the device took between five and 20 minutes
to detect and signal the presence of a harmless biological agent called
B. globigii. The only mishap occurred when radio interference caused the
plane's operator to lose control of the plane, which staged an auto-pilot-controlled
crash landing in a patch of sagebrush. The plane, which was originally
designed to string telegraph lines across Germany, was ruined, but the
biosensor survived intact.
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- Since the Gulf War the American military
has been on alert over Iraq's alleged covert program to build an arsenal
of biological weapons. Documentation has shown that Iraq possessed deadly
bacterial agents before and during the Gulf War, but did not use them.
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- Biological weapons like anthrax can infect
a human by a single exposure through the skin or lungs. The infection then
leads to symptoms, such as fever, blisters, nausea and labored breathing.
If launched during the right weather conditions less than a gallon of anthrax
can kill thousands.
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- As a defense against stockpiles of infectious
germs, the U.S. military currently inoculates its troops against certain
bacterial agents. But Tucker says depending only on vaccinations is a flawed
approach. "There's no way to vaccinate people against every conceivable
agent. It's impossible," he said. The best answer, he says, is to
detect early and be prepared.
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- And the best biowarfare scout, others
claim, is the kind without a pulse.
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- "Unmanned vehicles are transportable,
they're mobile, they take up little space," said Daryl Davidson, executive
director of Association for Unmanned Vehicles. "There's no need to
put a person at risk when you can do the same mission with the unmanned
vehicle."
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