July 23, 2007, 6:59 PM CT

spontaneous way to duplicate beauty of nature

There are a number of objects in nature, such as flowers, that are pre-programmed to develop into delicate, beautiful and intrically shaped forms. But can this pre-determined process be duplicated by man starting with plain, flat surfaces".

Yes, say Dr. Eran Sharon and his co-workers, Yael Klein and Efi Efrati, at the Hebrew University of Jerusalem Racah Institute of Physics, who have succeded for the first time anywhere in programming polymer sheets to bend and wrinkle by themselves into prescribed structures. Their work was described in the journal Science.

They made flat discs of a soft gel that, when warmed gently, curved into domes, saddles and even sombrero shapes. Such switchable shape control in a soft material could have applications ranging from optics to biomedicine.

The sheets change shape because the gel a web of cross-linked polymers shrinks at temperatures above 33 degrees celcius by an amount determined by the local polymer density.

When the density varies across the disc, the sheet buckles to relieve the pressure of uneven shrinkage. The scientists worked out what shrinkage patterns would produce the structures they wanted, then used an automated mixing system to produce cocktails of gels with the right properties......... Posted by: Kevin      Read more         Source

July 23, 2007, 6:55 PM CT

A novel molecular dictator 'with a conscience' discovered

UNSW scientists have uncovered an important naturally occurring mechanism in the body where "bad" cells that cause blockages in our blood vessels are kept under strict growth control, while "good" cells that keep our blood vessels free of clots and growths are left unaffected.

The discovery is expected to benefit those who will need heart coronary bypass surgery, an angioplasty - the mechanical widening of a narrowed or totally blocked blood vessel - or will undergo haemodialysis.

Professor Levon Khachigian, from UNSW's Centre for Vascular Research, who previously pioneered "molecular assassin" drug technology, describes this novel mechanism he discovered as "a molecular dictatorship with a conscience".

"The dictator is a specific gene suppressor called YY1, which has the therapeutically appealing capacity to differentiate between certain cell types when it goes about its activity," says Professor Khachigian.

This key finding has just been reported in the world's premier cardiovascular research journal, Circulation Research.

Professor Khachigian's research provides new hope in tackling the global problems of coronary bypass graft failure, and restenosis - the closing or narrowing of an artery that was previously opened by a procedure such as angioplasty......... Posted by: Sarah      Read more         Source

July 23, 2007, 4:59 PM CT

Spark-free, Fuel-efficient Engines

In an advance that could help curb global demand for oil, MIT scientists have demonstrated how ordinary spark-ignition automobile engines can, under certain driving conditions, move into a spark-free operating mode that is more fuel-efficient and just as clean.

The mode-switching capability could appear in production models within a few years, improving fuel economy by several miles per gallon in millions of new cars each year. Over time, that change could cut oil demand in the United States alone by a million barrels a day. Currently, the U.S. consumes more than 20 million barrels of oil a day.

The MIT team presented their latest results on July 23 at the Japan Society of Automotive Engineers (JSAE)/Society of Automotive Engineers (SAE) 2007 International Fuel and Lubricants Meeting.

A number of scientists are studying a new way of operating an internal combustion engine known as "homogeneous charge compression ignition" (HCCI). Switching a spark-ignition (SI) engine to HCCI mode pushes up its fuel efficiency.

In an HCCI engine, fuel and air are mixed together and injected into the cylinder. The piston compresses the mixture until spontaneous combustion occurs. The engine thus combines fuel-and-air premixing (as in an SI engine) with spontaneous ignition (as in a diesel engine). The result is the HCCI's distinctive feature: combustion occurs simultaneously at a number of locations throughout the combustion chamber......... Posted by: Kevin      Read more         Source

July 17, 2007, 10:21 PM CT

Natural 'workbench' For Nanoscale Construction

Engineers at the University of Pennsylvania have taken a step toward simplifying the creation of nanostructures by identifying the first inorganic material to phase separate with near-perfect order at the nanometer scale. The finding provides an atomically tuneable nanocomposite workbench that is cheap and easy to produce and provides a super-lattice foundation potentially suitable for building nanostructures.

The findings are reported in the recent issue of Nature Materials.

Alerted by an unusual diffraction effect of a common ceramic material, scientists used imaging to identify a two-phase structural pattern ideal as the first step towards nanodevice construction. Practical application of nanotechnology will rely upon engineerings ability to manipulate atoms and molecules into long-range order to produce materials with desired functionalities. The Penn findings provide a simpler method for the ordering of composite parts on the nanometer scale, which is integral to the incorporation of nano-objects such as particles and wires that make up nanodevices.

The material used in the Penn study is an ionically- conductive, crystalline ceramic (Nd2/3-xLi3x)TiO3 that engineers observed with transmission electron microscopy. The powdered perovskite exhibited two distinct patterns at the atomic scale with identical periodicity: a nanoscale chessboard pattern and a diamond pattern that indicated periodic separation into two phases within the structure. This spontaneous separation of phases could present a new foundation on which to build nanodevice technology. This material made using standard and easily reproducible ceramic processing methods represents the formation of a spontaneous microscopic surface controlled on the nanoscale with atomic precision......... Posted by: Kevin      Read more         Source

Thu, 12 Jul 2007 05:19:54 GMT

Whirlpool Offers COOL News

Hot on my list of cool things is the latest innovation from Whirlpool. While not quite in stores yet, if you are in the market for a new dryer or washer and dryer duo, these innovative stackable units deliver some cutting edge technology.. one might call it even steamy!

The new Duet steam dryer delivers steam technology that relaxes wrinkles and removes odors right inside the dryer. It uses a gentle, yet powerful combination of mist and heat in the dryer, allowing the garment to be dry, refreshed and ready-to-wear as soon as the cycle is finished. Think about this? No more last minute ironing! No more running clothing to the dry cleaners for pressing!! SAVE $$$

The Duet steam dryer uses a water line from the washer to spray a fine mist on clothes. The water vapor gently penetrates fabrics to lift odors and relax wrinkles while drying.

For clothes that just need a quick freshening, the Quick Refresh cycle relaxes wrinkles and removes odors in about 15 minutes. For those that "over dry" or leave clothes left in the dryer too long after the cycle was finished, the Duet steam dryer features an Enhanced Touch-Up cycle which relaxes the wrinkles in 20 minutes.

Here's a bonus feature that I love love love: Duet steam dryer's AccelerCare- drying system which minimizes drying time so that dry time equals wash time. Once you start the dryer and the washer at the same time, they will finish at the SAME TIME!!

Whirlpool has updated, intuitive controls that feature pre-programmed cycles and option settings for effortless cycle selection - so you can load & go. Posted by: Stevie Wilson      Read more     Source

July 5, 2007, 9:10 PM CT

Coaching Computer Canines

The mutts are metal, the size of toy poodles, with four pointy feet ending in little balls. They need to learn how to make their way on those little feet across a treacherous terrain of broken rocks. University of Southern California roboticist Stefan Schaal has just won renewal of a $1.5 million DARPA contract to train them to do so.

Schaal, an associate professor in the USC Viterbi School of Engineering department of computer science, began working on the problem more than a year ago.

Four- and six-legged robots have been walking around for years, he noted - but most just on smooth surfaces where wheels are a more efficient of getting around.

"What you really want legged robots for is to negotiate difficult terrain," he says. " This project is designed to push that envelop".

Boston Dynamics builds the 'bots, which come with an onboard computer chip connected to sensors.

The robot is continually aware of the location of its center of gravity.The strategy for walking, as explained in a paper Schaal presented at the 2007 IEEE International Conference on Robotics and Automation, was "to adjust a smooth walking pattern generator with the selection of every foot placement such that the center of gravity. follows a stable trajectory"......... Posted by: Kevin      Read more         Source

July 5, 2007, 8:57 PM CT

The New "Look" Of Superconductivity

Like the surface motif of a bubble bath, the spatial distribution of a magnetic field penetrating a superconductor can exhibit an intricate, foam-like structure. Ruslan Prozorov at the U.S. Department of Energy's Ames Laboratory has observed these mystifying, two-dimensional equilibrium patterns in lead samples when the material is in its superconducting state, below 7.2 Kelvin, or minus 446.71 degrees Fahrenheit.

Through innovative research to relate the complex geometry of the equilibrium patterns to the macroscopic physical properties, such as magnetism, Prozorov has shown that the shape of the entire sample determines the pattern topology and overall magnetic behavior of the system - a significant finding that represents a major contribution to the field of superconductivity. "You can have the same volume and same mass, but if you just change the shape, you get a different type of response from the sample and a different type of geometry of the equilibrium field pattern," he said. "The discovery has reopened the whole field of equilibrium in type-I superconductors, which had gone dormant because it was considered closed." .

Prozorov's discovery of the complex patterns in superconducting lead marks a noteworthy departure from the model first proposed by Russian physicist Lev Landau in the 1930s. Landau's model, which resembles a labyrinth or laminar pattern, has been the unchallenged standard in physics textbooks for 70 years......... Posted by: Kevin      Read more         Source

June 29, 2007, 5:08 AM CT

Bright future for nanosized light source

A bio-friendly nano-sized light source capable of emitting coherent light across the visible spectrum, has been invented by a team of scientists with the U.S. Department of Energys Lawrence Berkeley National Laboratory, and the University of California at Berkeley. Among the a number of potential applications of this nano-sized light source, once the technology is refined, are single cell endoscopy and other forms of subwavelength bio-imaging, integrated circuitry for nanophotonic technology, and new advanced methods of cyber cryptography.

Working with individual nanowires, weve developed the first electrode-free, continuously tunable coherent visible light source thats compatible with physiological environments, said chemist Peidong Yang, one of the principal researchers behind this project, and a leading nanoscience authority who holds joint appointments with Berkeley Labs Molecular Foundry and Materials Sciences Division, and the UC Berkeley Chemistry Department.

Weve also demonstrated that it is possible to trap and manipulate single nanowires with optical tweezers, a critical capability not only for bio-imaging but also for wiring together nanophotonic circuitry.

Jan Liphardt, a biophysicist who holds a joint appointment with Berkeley Lab's Physical Biosciences Division and UC Berkeleys Physics Department, was another principal investigator for this research......... Posted by: Kevin      Read more         Source

June 28, 2007, 11:54 PM CT

New, Invisible Nano-fibers

Tiny plastic fibers could be the key to some diverse technologies in the future -- including self-cleaning surfaces, transparent electronics, and biomedical tools that manipulate strands of DNA.

In the recent issue of the journal Nature Nanotechnology, Ohio State University scientists describe how they created surfaces that, seen with the eye, look as flat and transparent as a sheet of glass. But seen up close, the surfaces are actually carpeted with tiny fibers.

The patent-pending technology involves a method for growing a bed of fibers of a specific length, and using chemical therapys to tailor the fibers' properties, explained Arthur J. Epstein, Distinguished University Professor of chemistry and physics and director of the university's Institute for Magnetic and Electronic Polymers.

"One of the good things about working with these polymers is that you're able to structure them in a number of different ways," Epstein said. "Plus, we observed that we can coat almost any surface with these fibers".

For this study, the researchers grew fibers of different heights and diameters, and were able to modify the fibers' molecular structures by exposing them to different chemicals.

They devised one therapy that made the fibers attract water, and another that made the fibers repel water. They found they could also make the surfaces attract or repel oil. Depending on what polymer they start with, the fibers can also be made to conduct electricity......... Posted by: Kevin      Read more         Source

June 25, 2007, 7:36 PM CT

Building Nanodevices In The Lab

Philadelphia -- Physicists at the University of Pennsylvania are using a new technique to craft some of the tiniest metal nanostructures ever created, none larger than 10 nanometers, or 10,000 times smaller than the width of a single human hair.

The technique employs transmission electron beam ablation lithography, or TEBAL, to carve nanostructures from thin sheets of gold, silver, aluminum and other metals. TEBAL provides a more dependable method for producing quality versions of these microscopic devices, which are studied for their novel mechanical properties and their potential use in next-generation sensors and electronics. The method also permits simultaneous, real-time atomic imaging of the devices as they are made.

Traditional techniques for building nanodevices employ electron beam lithography but also require the use of polymers and chemicals in which the metal is evaporated. Typical results are closer to 50 nanometers in size and rarely as small as 10.

Marija Drndi, professor of physics at Penn, and her team created nanodisks, nanorings, nanowires, nanoholes and multi-terminal nano-transistors. The results were reported in the journal Nano Letters.

A number of different approaches have been undertaken to fabricate the small structures needed to probe the phenomena that take place at the nanoscale, but the most widely used and versatile techniques are limited to tens of nanometers, Drndi said. Reliably and consistently fabricating devices at the sub-10-nanometer scale from the top down is generally still challenging, but our technique offers a route to this regime......... Posted by: Kevin      Read more         Source