Following a roadmap for organic and printed electronics a new concept for a very cheap plastic nanotech memory has been developed by combining the favorable properties of ferroelectrics and semiconductors. From the University of Groningen, via Nanowerk News “Researchers develop ultra low-cost plastic memory“

Researchers at the Zernike Institute of Advanced Materials at the University of Groningen have developed a technology for a plastic ferro-electric diode which they believe will achieve a breakthrough in the development of ultra low-cost plastic memory material. Their findings will be published in the July edition of Nature Materials [abstract], a publication of the leading scientific journal Nature.

The newly developed technology is similar to that used in Flash memory chips. In both cases, the memory retains data without being connected to a power source. Flash memory chips are used in memory sticks, MP3 players, cellular phones and in the memory cards of digital cameras. The researchers at the Zernike Institute of Advanced Materials expect the new technology to lead to the development of comparable products possibly even more significant. One product they have in mind is an electronic price tag which could be read radiographically at the cash desk of retail stores, replacing the bar codes currently in use. Another possible application is for the material to be used in packaging material which could warn consumers when a product is nearing its expiration date.

…The breakthrough … is based on a radically new concept: instead of stacking a layer of semiconducting material on a layer of ferro-electric material, a mixture of these two materials is used. The ferro-electric characteristic of the mixture is then used to direct current through the semi-conducting part of the mixture.

The new memory diode can be programmed quickly, retains data for a long time and operates at room temperature. The voltages needed for programming are low enough for the diode to be used in commercial applications and the material can be manufactured at low cost using large-scale industrial production techniques.

—Jim

While searching for genes involved in how bacteria stop moving around and settle into stationary communities called biofilms, scientists discovered a molecular clutch that disengages the powerful molecular motor that spins the flagellum that propels the bacteria. This flagellum clutch mechanism may provide ideas useful for nanotech control of molecular motors. From Indiana University, via AAAS EurekAlert “Microscopic ‘clutch’ puts flagellum in neutral“:

A tiny but powerful engine that propels the bacterium Bacillus subtilis through liquids is disengaged from the corkscrew-like flagellum by a protein clutch, Indiana University Bloomington and Harvard University scientists have learned. Their report appears in this week’s Science [abstract].

Scientists have long known what drives the flagellum to spin, but what causes the flagellum to stop spinning — temporarily or permanently — was unknown.

“We think it’s pretty cool that evolving bacteria and human engineers arrived at a similar solution to the same problem,” said IU Bloomington biologist Daniel Kearns, who led the project. “How do you temporarily stop a motor once it gets going?”

The action of the protein they discovered, EpsE, is very similar to that of a car clutch. In cars, the clutch controls whether a car’s engine is connected to the parts that spin its wheels. With the engine and gears disengaged from each other, the car may continue to move, but only because of its prior momentum; the wheels are no longer powered.

EpsE is thought to “sit down,” as Kearns describes it, on the flagellum’s rotor, a donut-shaped structure at the base of the flagellum. EpsE’s interaction with a rotor protein called FliG causes a shape change in the rotor that disengages it from the flagellum’s proton-powered engine.

…The discovery may give nanotechnologists ideas about how to regulate tiny engines of their own creation. The flagellum is one of nature’s smallest and most powerful motors — ones like those produced by B. subtilis can rotate more than 200 times per second, driven by 1,400 piconewton-nanometers of torque. That’s quite a bit of (miniature) horsepower for a machine whose width stretches only a few dozen nanometers.

—Jim