Nano-sized carbon tubes coated with strands of DNA can create tiny sensors with abilities to detect odors and tastes, according to researchers at the University of Pennsylvania and Monell Chemical Sciences Center. Their findings are published in the current issue of the journal Nano Letters, a publication of the American Chemical Society.

According to the researchers, arrays of these nanosensors could detect molecules on the order of one part per million, akin to finding a one-second play amid 278 hours of baseball footage or a single person in Times Square on New Years' Eve. In the report, the researchers tested the nanosensors on five different chemical odorants, including methanol and dinitrotoluene, or DNT, a common chemical that is also frequently a component of military-grade explosives. The nanosensors could sniff molecules out of the air or taste them in a liquid, suggesting applications ranging from domestic security to medical detectors.

The main objectives of the project are (i) to develop versatile, inexpensive, and easy-to-use diagnostic tools for health, environmental and other applications based on the measurement of molecular interactions (ligand-receptor interactions) by integrated micro- and nano-cantilever sensors and (ii) to test the developed diagnostic tools in two specific health care applications, namely (1) the detection of tumour markers in clinical diagnosis and (2) the high-sensitivity detection of proteins, providing a verification of the project's achievements and initiating a generation of innovative products with significant market potential. The proposed project capitalizes on the mechanical properties of micro- and nano-mechanical structures (cantilevers) to measure molecular (ligand-receptor) interactions.

By the light of flashlights and a crescent moon, the three-member crew catapults a 300-pound pilotless airplane into the sky.

Minutes later, other U.S. soldiers behind a computer screen inside a shed monitor video images from the plane, known as a Shadow, as it loiters over a traffic circle frequently attacked by insurgent bombs.

"We fill some of the gaps in the intelligence field. We put one of these in harm's way instead of a soldier. It's all about saving lives," says Sgt. Francisco Huereque, who is in charge of the night's launch.

Unmanned aerial vehicles and other so-called "stand-off" weapons, whether currently used or in secret testing, belong to a developing high-tech arsenal that the U.S. military says will help minimize casualties as it battles insurgents.

A team of researchers have developed a method that could vastly improve the ability of atomic force microscopes to "see" the chemical composition of a sample, follow variations of the sample, as well as map its topographic structure.

The advance could have significant implications for drug development by allowing scientists to monitor the effects of potential drugs on an ever-smaller scale, according to Stuart Lindsay, director of the Center for Single Molecule Biophysics at the Biodesign Institute at Arizona State University and a lead researcher on the project.

Lindsay, an ASU professor in the department of physics and astronomy said the new technique allows an atomic force microscope to "see," on a nanometer scale, the chemical composition of molecules.

"Atomic force microscopy has a resolution down to an atomic level, but until now it has been blind to identifying specific chemical compositions," Lindsay said.

The researchers -- Lindsay, Hongda Wang, Ralph Bash, Brian Ashcroft, and Dennis Lohr of Arizona State University; Cordula Stroh, Hermann Gruber and Peter Hinterdorfer of the Institute of Biophysics at the University of Lintz, Austria; and Jeremy Nelson of Molecular Imaging Corporation, Tempe, Ariz. -- present their findings in "Single Molecule Recognition Imaging Microscopy" in the current issue of the Proceedings of the National Academy of Sciences.

Thermal imaging technology is about to undergo a revolution. Raytheon Infrared introduces the Thermal-Eye 3500AS thermal imaging core with Thermal-Eye Advanced Image Processing technology. This new product provides sophisticated images and color capabilities unsurpassed in its class.

"With the introduction of the 3500AS, our Thermal-Eye products have become demonstrably better than they've ever been, and they're only going to continue to improve," said Raytheon Infrared President Chris Bade.

New technology soon could transform all objects in a room into touch-sensitive remote control devices, even if they do not run on electricity, French scientists told United Press International.

The idea is every sound wave "contains all the information to locate where its source was," said physicist Mathias Fink at Université Paris 7.

In experiments, the researchers found touching an object, such as a window or a table, generates vibrations that are easily detectable with one or two acoustic sensors placed on the item in question.

Physicists have discovered a new signature characteristic of radiation that could be used to detect the gamma ray emissions of smuggled illegal nuclear materials, even if they are concealed among large bundles of shipping containers.

The problem of detecting smuggled nuclear weapons or devices presents an enormous challenge for security officials. More than 6 million containers enter U.S. ports annually. West Coast facilities alone process about 11,000 a day, or an average of eight every minute. A single container can hold up to 57,000 pounds.

Officials have been attempting to figure out how to inspect containers for smuggled nuclear materials without disrupting the flow of the nation's commerce.

The physicists, from Lawrence Livermore National Laboratory in Berkeley, Calif., think they have come up with the solution.

"We have identified a new radiation signature, unique to fissionable material, that exploits high-energy, fission-product, beta-delayed, gamma ray emissions," said lead researcher Thomas Gosnell. "Fortunately, this signature is robust in that it is very distinct compared to normal background radiation, where there are no comparable high-energy gamma rays."

For two decades, chemists have been making great strides in analyzing the biological functions that drive living cells. But many biological substances still remain undetectable.

That will soon change, thanks to a biological sensor being developed by University of Arizona chemists. Their new sensor platform has many capabilities that current ones lack.

Most intracellular sensors are made from hard plastics (polymers). The plastic is formed into solid, nanometer-sized, BB-like beads, which are doped with chemicals. These chemicals make them sensitive to a variety of ions and molecules. But scientists can only detect intracellular compounds that react optically with these chemicals.

Current biological sensors have several other drawbacks. Imaging dyes and proteins, fiber optics sensors, and coated nano-sized beads can disrupt cellular processes. In addition, they sometimes break down chemically or can be toxic. They also can't reveal the kinds of chemical processes occurring or their rates of reaction in real time. And they can't detect large molecules, such as proteins.

"Our new technology takes advantage of some very specific and useful biology," said UA chemist Craig Aspinwall. "It's the ability of ions, molecules or groups of molecules to interact with certain proteins. We can use those proteins to report the presence of specific ions and molecules."

Aspinwall takes an unconventional approach to constructing tiny devices that safely transport and hold these proteins within a cell.

He starts by making nanometer-sized hollow shells of phospholipids that self-assemble. The self-assembled phospholipids are then "polymerized," or chemically linked, to form the sensors. Since phospholipids are the major component of cell membranes, they are biocompatible. A hundred can be released inside a cell without affecting cellular functions. The shells' hollow shape allows them to safely hold water-soluble — or even toxic — indicator dyes and enzymes that can be used to ferret out the details of chemistry inside living cells.

In short, chemists can select proteins that interact with specific ions, molecules or groups of molecules, stick them into nanoshell membranes, and send them inside the cell to sniff out specific substances.

Philips Research at the CeBIT exhibition is demonstrating a unique variable-focus lens system that has no mechanical moving parts. Suited to a wide range of optical imaging applications, including digital cameras. Philips’ FluidFocus system mimics the action of the human eye using a fluid lens that alters its focal length by changing its shape. The new lens, which lends itself to high volume manufacturing, overcomes the fixed-focus disadvantages of many of today’s low-cost imaging systems.

The Philips FluidFocus lens consists of two immiscible (non-mixing) fluids of different refractive index (optical properties), one an electrically conducting aqueous solution and the other an electrically non-conducting oil, contained in a short tube with transparent end caps. The internal surfaces of the tube wall and one of its end caps are coated with a hydrophobic (water-repellent) coating that causes the aqueous solution to form itself into a hemispherical mass at the opposite end of the tube, where it acts as a spherically curved lens.

The shape of the lens is adjusted by applying an electric field across the hydrophobic coating such that it becomes less hydrophobic – a process called ‘electrowetting’ that results from an electrically induced change in surface-tension. As a result of this change in surface-tension the aqueous solution begins to wet the sidewalls of the tube, altering the radius of curvature of the meniscus between the two fluids and hence the focal length of the lens. By increasing the applied electric field the surface of the initially convex lens can be made completely flat (no lens effect) or even concave. As a result it is possible to implement lenses that transition smoothly from being convergent to divergent and back again.

Since 1776, when naval mines were invented, navies have rightfully feared the stealthy and relatively simple weapons, which can disable or destroy warships and paralyze vital shipping. Navies worldwide employ a host of mine-detection technologies and techniques, most of them complicated, expensive, and far from perfect. So a simpler, more effective method for detecting these mines, developed by a physicist at North Carolina State University, could make big waves in naval headquarters around the globe.

Unlike current mine-detection techniques, the patented methodology finds objects buried in the ocean floor without the use of complex, unreliable modeling and without the usual arrays of sonar transmitters and receivers. Instead, the method records the return echo of a sonar transceiver’s “ping,” then time-reverses and transmits that signal. The following echo clearly shows buried objects, and suppresses the response from the seafloor itself, making the underwater terrain “transparent.”

Ultimately, fighting the war on terrorism may have less to do with giant aircraft carriers and more to do with atomic-scale detection and prevention systems. Nanotechnology, which is expected to transform everything from computer processors to drug delivery systems, may also be the key to homeland security, argues a new book.

In Nanotechnology and Homeland Security: New Weapons for New Wars (Prentice Hall, 2003), Mark A. Ratner, a professor of chemistry at Northwestern University and a noted expert in molecular electronics, and his son Daniel Ratner, a high-tech entrepreneur, claim that current research in nanotechnology will lead to intelligent sensors, smart materials, and other methods for thwarting biological and chemical attacks.

The microprocessor giant is thinking even smaller: tiny sensor chips that network with each other - inside everything on earth.

As a department head at the Defense Advanced Research Projects Agency, the Pentagon's R&D arm, David Tennenhouse spent the late 1990s approving or denying funding for hundreds of far-out military programs. One proposal he reviewed, from a research team at UC Berkeley, outlined a concept called smart dust - fleck-sized wireless sensors intelligent enough to organize themselves into autonomous networks. Dropped from a passing helicopter, the sensors could spy on enemy movements or detect a hidden stash of mustard gas. Tennenhouse was intrigued enough to authorize several hundred thousand dollars in funding. Then he moved on to the next bizarre proposal.

A new invention can sniff like a dog, find drugs like a dog and help police catch criminals like a dog. But can the so-called "Dog on a Chip" replace the police officer's best friend?

At some point in the future, nanosensors, generally defined as "devices" capable of sensing and responding to physical stimuli with dimensions on the order of one billionth of a meter, will revolutionize the detection of biological and chemical substances, displacement and motion, force and mass, and acoustic, thermal and electromagnetic stimuli. This report will highlight the recent work in nanosensor development, which has been notable in the areas of nanomaterials, nanoparticles and nanodevices (particularly nanotubes) for biotechnological, chemical and gas applications.