Innovation and Technology Weekly – No. 14, 2006

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Issue 14, 2006

This week's headlines:

Viruses 'trained' to build tiny batteries
April 06, 2006

Researchers trying to make tiny machines have turned to the power of nature, engineering a virus to attract metals and then using it to build minute wires for microscopic batteries. The resulting nanowires can be used in minuscule lithium ion battery electrodes, which in turn would be used to power very small machines.

The international team of researchers, led by a group at MIT, used the M13 virus, a simple and easily manipulated virus. They modified the M13 virus' genes so its outside layer, or coat, would bind with certain metal ions. They incubated the virus in a cobalt chloride solution so that cobalt oxide crystals mineralised uniformly along its length. They added a bit of gold for the desired electrical effects.

Viruses cannot reproduce on their own but must be grown in cells - in this case, bacteria. They inject their genetic material, and then the cells pump out copies of the virus. The viruses formed orderly layers and the resulting nanowires worked as positive electrodes for batteries. The researchers hope to build batteries that range from the size of a grain of rice up to the size of existing hearing-aid batteries.

Full story: MSNBC / Reuters / Science Back to top

Researchers grow tiny nanotube brushes
April 06, 2006

Tiny nanotube brushes with bristles more than thousand times finer than a human hair have been created by researchers of Rensselaer Polytechnic Institute and the University of Hawaii.

The brushes can be used to sweep up nanodust, as electronic micro-switches, to paint micro capillaries, and even clean up pollutants in water. The bristles' incorporate carbon nanotubes measuring just 30 nm across that are flexible enough to yield when pushed from the side. The scientists grew the bristles from hot, carbon-laden gas on to very fine threads of silicon carbide.

Conventional brush bristles, made of animal hairs, synthetic polymer fibres, and metal wires, are prone to break down at the nanoscale. To work at the nano-scale, researchers realised that a different kind of material was needed. The small size, strength, elasticity, and ability to conduct electricity make carbon nanotubes ideal bristle material, the scientists reported.

Full story: Information Week / EE Times Back to top

Scientists build liquid crystal bifocals
April 04, 2006

Eyes lose their flexibility with age, sometimes making it difficult to shift focus from near to far or vice versa. Benjamin Franklin devised bifocals - eyeglass lenses shaped for near viewing in the lower half and distance vision in the upper portion - more than 200 years ago. Now researchers have created liquid crystal lenses that can change between long-distance and reading modes with the flick of a switch.

Researcher at the University of Arizona sandwiched a thin layer of liquid crystal between two layers of glass and laced it with concentric rings of electrodes. When turned on, the electrodes reconfigure the focusing power of the lens for either near or far vision, allowing the entire lens to promote the desired effect in less than a second.

In tests on both human and mechanical subjects, the liquid crystal lens delivered a sharp image whether focusing on the close at hand or the distant. If the electrical current fails, the lens simply reverts to its distance-viewing state. Because most people requiring bifocals have difficulty seeing up close rather than far away, this feature makes the glasses safe for activities like driving, the scientists argue.

Full story: Scientific American Back to top

Tuning for oil
April 04, 2006

Wealthy oil companies are always looking for ways to save money and time, and this simple invention for finding underground oil reserves may help them do both.

The usual practice is to take fluid samples from the ground and wait several weeks for lab analysis to confirm the presence of H2S and CO2 , which signals a likely oil strike. The new idea, from oil company Baker Hughes - part of the Howard Hughes empire - is to make compounds near oil reserves literally sing out. Or, more accurately, sing out of tune.

A vacuum cylinder, sealed with a semi-permeable membrane of silicone rubber, would be lowered down into a shaft. Gases should diffuse into the chamber and settle on a pair of gently vibrating 'tuning forks', one coated with a thin layer of silver, which absorbs H2S, and the other with a layer of sodium oxide, which takes up CO2.

As the fork's surfaces absorb the gases, they will get slightly heavier and their resonant pitch will fall in frequency. This is detected by an audio sensor which signals detection of the gases. The more the pitch falls, the higher the gas concentration and the better the chances of finding oil.

Full story: New Scientist Back to top

Polyester fabric neutralises stun gun jolt
April 05, 2006

US firm G2 Consulting has come up with a fabric that takes the powerful sting out of being hit with a stun gun or a cattle prod.

Thor Shield is a polyester fabric bonded to a conducted material that effectively loops the electricity coming from a nonlethal electricity weapon back to the weapon. The light, breathable material is for sale to law enforcement agencies and the military only and could protect officers from being injured by their own weapons.

Tasers and other electricity weapons work by jolting a person's body with enough electricity to overwhelm their neuromuscular system. When fired, a Taser launches two probes, connected to the gun by wires. When the probes hit a person's body, they create a circuit and 50,000 volts that pass through an individual's system. A hit from a stun gun is incredibly painful and knocks individuals instantly to the ground in most circumstances.

Because Thor Shield is conductive, it can complete the circuit with probes without having the electricity pass through an individual's body.

Full story: CNET News Back to top

Fly me to the moon - by catapult
April 03, 2006

It may read like a far-flung plotline from a science-fiction comic, but Scottish scientists have unveiled plans to develop a giant slingshot to catapult material from the earth to the moon.

The project - by the University of Glasgow - will explore whether it is theoretically possible to create massive cables then use the power of the earth's orbit to catapult raw materials for mining, food, water and aerospace equipment into space. The cables could be up to 250,000km long and made of extra strong materials such as Kevlar, tungsten, graphite or carbon nano- fibres.

The Glasgow team beat 50 other applicants to win EUR 10,000 from the European Space Agency for the three-month study, which aims to examine the maths behind such a system, rather than make a physical model of the slingshot.

Full story: The Scotsman Back to top

Prehistoric man invented dental drill 9,000 years ago
April 05, 2006

Primitive dentists drilled nearly perfect holes into live but undoubtedly unhappy patients between 5500 BC and 7000 BC, researchers at the University of Poitiers, France, have found.

The researchers carbon-dated at least nine skulls with 11 drill holes found in a Pakistan graveyard. That means dentistry is at least 4,000 years older than first thought and far older than the useful invention of anaesthesia. The drilled teeth found in the graveyard were hard-to-reach molars. And in at least one instance, the ancient dentist managed to drill a hole in the inside back end of a tooth, boring out toward the front of the mouth. The holes went as deep as 3.5mm.

The researchers think that a small bow was used to drive the flint drill tips into patients' teeth. They simulated the technique and drilled through human teeth in less than a minute. The dentistry, probably evolved from intricate ornamental bead drilling that was also done by the society there, went on for about 1,500 years until about 5500 BC. After that, there were no signs of drilling. The researchers think the drilling was done to reduce the pain of cavities.

Full story: Yahoo! / AP / Nature Back to top