| Biobots
Prototype nanoscale biomedical devices exist that could deliver drugs to
precise targets inside your body, or carry out internal repairs on the spot.
Some are made of natural molecules; others are hybrids of molecules and
artificial parts. One group of molecular virologists has made a nanoscale motor
from all-natural viral RNA and DNA. It runs on natural chemical fuel, and has
already been tested inside a cell to destroy a hepatitis virus.
Another team is building hybrid nanodevices called “biobots” from natural
molecules and manmade parts, for use in space exploration. The lead researcher
has already developed a nanocopter consisting of a virus-sized biomotor and a
nickel propeller mounted on a nickel post. The biocomponent converts the body’s
chemical fuel into energy to drive the motor and turn the propeller. A
submersible derivative of this device could be delivering or even manufacturing
drugs in the human body, though probably not for at least a decade.
Nanoscale electric generators that could become artificial nerve cells or
even parts of a computer structured like the human brain are also under
development. They could be used as a jumper cable to reconnect severed nerves,
and as pacemakers.
Reference: Cunningham, Ann Marie (2003). “BioBots.”
ScienCentral, May 22.
Bioterror Early Warning Device
While some scientists strive to create ultra-delicate electronic noses to
sniff out specific pathogens and chemicals used in bioterror attacks, one team
has come up with the equivalent of a “coal mine canary-on-a-chip.” The “canary”
is a single living cell. If there’s poison in the air, the cell will die. We can
see a dead or dying canary, but not (without cumbersome microscopy) a dead or
dying cell. The new chip monitors the electrical resistance of the cell’s
membrane, which spikes if the cell dies, and the chip then triggers an alarm.
The current version of the chip could work for days or weeks before the cell
dies a natural death. The cell is in a nutrient bath on a silicon wafer, with
live electrodes at both ends. A meter watches for the tell-tale spike.
Arizona State researchers have created something similar in concept,
consisting of a rat lung cell in a nutrient whirlpool bath. Chemical sensors
monitor for proteins excreted by a dying cell. That device “can detect almost
single molecules,” one of the researchers told a Wired correspondent. And
National Institute of Standards and Technology scientists have developed a
device containing a bacterium, which excretes potassium if attacked, and a
sensor to detect the potassium.
The benefit of a one-size-fits-all-pathogens-and-toxins approach, over the
pathogen/toxin-specific approach, is obvious. In addition, such devices have
other potential uses besides bioterror defense; such as in general environmental
or industrial pollution detection.
Reference: Unknown (2003). “Coal-Mine
Canaries on a Chip.” Wired News, June 13.
Face Recognition
PiXlogic is a recipient of funds from the CIA’s venture capital arm,
In-Q-Tel, to develop picture-monitoring software to match new pictures to ones
held in the CIA’s vast picture archives. In about a year, the software will
include improved face-recognition features. The software analyzes each
photograph or video frame, identifies items by geometry, color, and other
qualities, and stores those details in computer files that are easily searched
for matches.
The technology will eventually be sold to consumers to help organize their
growing digital picture libraries.
Reference: Bridis, Ted (2003). “CIA Developing
Software to Scour Photos.” Associated Press, June 3.
Intelligent Prosthetic Arm
Many people with high-tech prosthetic arms can control them naturally, by
thought, provided that they still have some movement in the surrounding muscles
which they can flex as if trying to move their arms. However, only relatively
coarse-grained actions, such as opening or closing an artificial hand, are
currently possible. A new microchip under development can read more of the
brain-muscle signals, giving much greater flexibility to the prostheses. Wearers
can not only open or close a hand but also move the wrist and elbow.
The technology has worked in preliminary trials on patients. More trials are
planned before the chip is made generally available. It can be retrofitted to
existing hardware.
Reference: Unknown (2003). “Microchip
promises smart artificial arms.” BBC News, June 15.
Technology for T-rays
Researchers have found a way to shift the frequency of light beams to any
desired frequency, with near 100 percent efficiency. Turning red light into blue
light — an astonishing feat in itself — would be a trivial example; the method
could do much more. The discovery was the unexpected outcome of sending shock
waves through a photonic crystal, a sandwich made of materials that bend light
in different ways. By changing the way the sandwich is made up, the researchers
found it is possible to produce any desired output frequency, including
terahertz rays (t-rays), which have a frequency in the range between microwaves
and infrared. T-rays hold great promise for medical imaging, but they have
hitherto been extremely difficult to produce.
The physics community is hailing this advance as revolutionary. Some work
remains to find a way of sending shock waves without destroying the crystal in
the process, but that is trivial relative to the proof of concept.
Reference: Choi, Charles (2003). “Alchemy with
light shocks physicists.” New Scientist, May 21. More articles on
t-rays can be found in the April 2003
and July
2003 issues of Health Futures Digest.
Plastics, 3-D Printer, Transparent
Displays
Silicon is somewhat difficult to work with, and therefore silicon transistors
— the guts of all computing — are somewhat expensive to manufacture, involving
sophisticated etching processes. Plastic is much easier to work with and
therefore plastic transistors would be much cheaper. Thanks first to the
development of conductive organic-polymer plastics* and now to the development
of a 3-D inkjet printing technology that forms small, vertical transistors from
layers of printed polymer, plastic transistors sufficiently compact to be
practical are now possible. The process could be used to print low-cost
electronics onto flexible surfaces, leading to inexpensive but very large active
matrix display screens, for example. The method could be in practical use in two
to five years.
Meanwhile, other researchers have made transparent transistors from cheap,
inorganic oxides. Plastic transparent transistors have been under development
since at least 1996 for use in electronic paper and flexible displays, but the
inorganic oxide transistors are sturdier and very efficient. However, they too
are expensive to produce, even with cheap inputs.
* More articles on such polymers are referenced in the March 2003
and April 2003
(and
again) issues of Health Futures Digest.
References: Unknown (2003). “Plastic Transistors
go Vertical.” Technology Research News, June 5, (URL lost), citing the
March 21, 2003 issue of Science; Unknown (2003). “See-Through
Circuits Closer.” Technology Research News, June 6. |
