A computer model that can predict how people will complete a controlled task and how the knowledge needed to complete that task develops over time is the product of a group of researchers, led by a professor from Penn State’s College of Information Sciences and Technology.

Frank Ritter, associate professor of IST and psychology, and his research associates, used the Soar programming language, which is designed to represent human knowledge, on a 20-trial circuit troubleshooting task most recently done by 10 students at the University of Nottingham, UK.

Each participant was to identify faults in a circuit system after memorizing the organization of its components and switches. This process was repeated 20 times for each person, with the series of tests chosen randomly each time. Their choices and reaction times were recorded and compared with the computer model’s results.

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Rods, cones, cubes and spheres – move aside. Tiny gold stars, smaller than a billionth of a meter, may hold the promise for new approaches to medical diagnoses or testing for environmental contaminants.

While nanoparticles have been the rage across a wide spectrum of sciences, a new study by Duke University bioengineers indicates that of all the shapes studied to date, stars may shine above all the rest for certain applications.

The key is light, and how that light reflects off the particles. Compared to the other shapes, nanostars can dramatically enhance the reflected light, the Duke scientists found. This increases their potential usefulness as a tracer, label, or contrast agent.

Since the researchers also found that the size and shape of the nanostars affect the spectrum of reflected light, they believe that these tiny nanostars can also be “tuned” to identify particular molecules or chemicals.

“To our knowledge, this is the first report of the development and use of gold nanostars as labels for molecular detection and description of their controlled synthesis with different sizes and shapes” said Chris Khoury, lead author of a paper published on-line in the Journal of Physical Chemistry. Khoury is a graduate student in biomedical engineering working in the laboratory of senior researcher Tuan Vo-Dinh, R. Eugene and Susie E. Goodson Distinguished Professor of Biomedical Engineering and director of The Fitzpatrick Institute for Photonics at Duke.
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University of Wisconsin-Madison engineers and physicists have developed a method of measuring how strain affects thin films of silicon that could lay the foundation for faster flexible electronics.

Silicon is the industry standard semiconductor for electronic devices. Silicon thin films could be the basis for fast, flexible electronics. Researchers have long known that inducing strain into the silicon increases device speed, yet have not fully understood why.

Developed by a team of researchers led by Max Lagally, the Erwin W. Mueller and Bascom Professor of Materials Science and Engineering at UW-Madison, the new method enables the researchers to directly measure the effects of strain on the electronic structure of silicon.

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Dutch researcher Koos Huijssen has developed a computer model that can predict the sound transmission of improved designs for ultrasound instruments. The computer model is capable of processing large quantities of data and can be run on both a PC and a parallel supercomputer. Erasmus University Medical Centre and Oldelft Ultrasound are now using this program to design a new sonographic transducer.

Koos Huijssen went in search of a computer model that could predict the behaviour of ultrasonic waves. Over the past ten years, the images produced by ultrasound or sonography have been vastly improved by making partial use of the nonlinear nature of acoustic waves. Thanks to these developments ultrasound can now be used for a larger group of patients.

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Researchers at Boston University working with collaborators in Germany, France and Korea have developed a nanoscale torsion resonator that measures miniscule amounts of twisting or torque in a metallic nanowire. This device, the size of a speck of dust, might enable measurements of the untwisting of DNA and have applications in spintronics, fundamental physics, chemistry and biology.

Spin-induced torque is central to understanding experiments, from the measurement of angular momentum of photons to the measurement of the gyromagnetic factor of metals and a very miniaturized – about 6 microns — version of a gyroscope that measures the torques produced by electrons changing their spin states. It can be used to uncover new spin-dependent fundamental forces in particle physics, according to Raj Mohanty, Boston University Associate Professor of Physics.

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NIST researchers have developed a new approach for “electronic noses.” Comprised of 16 microheater elements and eight types of sensors, the tiny device could be a potent tool for applications such as sniffing out nerve agents, environmental contaminants, and trace indicators of disease, in addition to monitoring industrial processes and aiding in space exploration

Researchers at The National Institute of Standards and Technology (NIST) have created a new approach to ‘electronic noses’, marrying a sensitive detector with a pattern-recognition module that mimics the way animals recognise colours.

According to a recent paper, the NIST electronic nose is more adept than conventional methodologies at recognising molecular features even for chemicals it has not been trained to detect, and is also robust enough to deal with changes in sensor response that come with wear and tear.

In animals, odorant molecules in the air enter the nostrils and bind with sensory neurons in the nose that convert the chemical interactions into an electrical signal that the brain interprets as a smell. In humans, there are about 350 types of sensory neurons and many copies of each type; dogs and mice have several hundreds more types of sensory neurons and many copies of each type; dogs and mice have several hundreds more types of sensory neurons on top of that.

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The UN estimates that more than 2,000 people are killed or injured by landmine explosions each month. A University of Missouri engineer is working to enhance the accuracy of a landmine radar system while minimizing the number of false alarms it produces.

In a landmine radar system, ground-penetrating radar scans the surface for underground objects. Besides sensing landmines, the radar also has undesirable responses from clutter objects, such as scrap metal debris, plant roots and rocks. Dominic Ho, the Dowell Professor of Electrical & Computer Engineering in the MU College of Engineering, is working with Army employees and private defense contractors to enhance the system, and distinguish between true positive signals that are from landmines and false positive signals that are from clutter objects and can be ignored safely.

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This schematic shows how a TSOM image is acquired. Using an optical microscope, several images of a 60 nanometer gold particle sample (shown in red) are taken at different focal positions and stacked together.

A technique under development at the National Institute of Standards and Technology (NIST) uses a relatively inexpensive optical microscope to quickly and cheaply analyze nanoscale dimensions with nanoscale measurement sensitivity. Termed “Through-focus Scanning Optical Microscope” (TSOM) imaging, the technique has potential applications in nanomanufacturing, semiconductor process control and biotechnology.

Optical microscopes are not widely considered for checking nanoscale (below 100 nanometers) dimensions because of the limitation imposed by wavelength of light—you can’t get a precise image with a probe three times the object’s size. NIST researcher Ravikiran Attota gets around this, paradoxically, by considering lots of “bad” (out-of-focus) images. “This imaging uses a set of blurry, out-of-focus optical images for nanometer dimensional measurement sensitivity,” he says. Instead of repeatedly focusing on a sample to acquire one best image, the new technique captures a series of images with an optical microscope at different focal positions and stacks them one on top of the other to create the TSOM image. A computer program Attota developed analyzes the image.

While Attota believes this simple technique can be used in a variety of applications, he has worked with two. The TSOM image can compare two nanoscale objects such as silicon lines on an integrated circuit. The software “subtracts” one image from the other. This enables sensitivity to dimensional differences at the nanoscale—line height, width or side-wall angle. Each type of difference generates a distinct signal.

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In this schematic of plasmonic lithography, the plasmonic flying head produces nanoscale patterns onto the spinning disk covered with photo sensitive chemicals. Ultraviolet light is delivered through the flying head onto the plasmonic lenses, which are used as optical styluses in this process. The setup resembles a stylus playing a record on traditional LP turntables.

Engineers at the University of California, Berkeley are reporting a new way of creating computer chips that could revitalise optical lithography, a patterning technique that dominates modern integrated circuits manufacturing.

By combining metal lenses that focus light through the excitation of electrons - or plasmons - on the lens’ surface with a “flying head” that resembles the stylus on the arm of an old-fashioned LP turntable and is similar to those used in hard disk drives, the researchers were able to create line patterns only 80 nanometers wide at speeds up to 12 meters per second, with the potential for higher resolution detail in the near future.

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By manipulating the way tiny droplets of fluid dry, Cornell researchers have created an innovative way to make and pattern nanoscale wires and other devices that ordinarily can be made only with expensive lithographic tools. The process is guided by molds that “stamp” the desired structures.

“You can in principle build almost any types of architectures you want at nanoscale,” reported Dan Luo, Cornell associate professor of biological and environmental engineering, postdoctoral researcher Wenlong Cheng and colleagues.

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Scientists at Clemson University for the first time have been able to make a practical optical fiber with a silicon core.

Led by Professor John Ballato and including fiber pioneer Roger Stolen, the team of scientists was able to create this new fiber by employing the same commercial methods that are used to develop all-glass fibers, making silicon fibers viable alternatives to glass fibers for selected specialty applications. This advance ultimately should help increase efficiency and decrease power consumption in computers and other systems that integrate photonic and electronic devices.
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Environmental gains derived from the use of nanomaterials may be offset in part by the process used to manufacture them, according to research published in a special issue of the Journal of Industrial Ecology.

According to a paper by Hatice ?engül and colleagues at the University of Illinois at Chicago, strict material purity requirements, lower tolerances for defects and lower yields of manufacturing processes may lead to greater environmental burdens than those associated with conventional manufacturing.

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Panasonic Fuel Cell Prototype for Notebooks.

Engineers at Panasonic will showcase their new reduced size methanol fuel cell at the Hydrogen Energy Advanced Technology Exhibition 2008 in Fukuoka, Kyushu, Japan. Japan’s most populated city will host the exhibit on October 22-24, 2008.

Panasonic has been working on reducing the size and efficiency of its previously introduced fuel cell over the past eight-years. The new methanol fuel cell is about the size of a laptop battery. The fuel cell battery weighs approximately 11.29-ounces and can deliver an average of 10-watts of power with a maximum output of 20-watts.

According to Panasonic, the new methanol fuel cell battery has the unique advantage of being able to run 20-hours utilizing 200cc methanol. When the fuel cell runs low on methanol a quick refueling takes a few minutes. Unlike lithium ion batteries, methanol fuel cells are viewed as more environmentally friendly. The only by-product is water and a slight amount of carbon dioxide.

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