Spot Nanoparticles

There is a growing interest in detecting nanoparticles and nanotechnologists are racing to build devices that can detect and characterise these particles. One method is having resonating devices that changes when a nanoparticle is bounced off the surface, measured by a laser. However this method is only ideal in certain cases and positions. Researchers from Washington University have a new vibrating micro-mushroom device that promises greater reliability in detecting nanoparticles.

Reference:
arxiv.org/abs/0912.0078

Penguin DNA Challenges Accuracy of Genetic Dating Techniques

Frozen DNA samples from penguins that died 44,000 years ago in Antarctica challenges the accuracy of traditional genetic aging measurements that underestimate the age of many specimens by several folds. Therefore, a biological specimen determined by traditional DNA testing can be two to six times older. DNA testing may be fundamentally flawed as a result of this discovery. The molecular clock rate is the key in determining the accuracy of genetic analysis.

Reference: Science Daily

Iris Recognition

Computer scientists at the National Institute of Standards and Technology (NIST) demonstrates that iris recognition algorithms can maintain their accuracy and interoperability for large-scale identity management applicaiton such as cyber security and counterterrorism. Iris recognition has emerged as the second most popular biometric characteristic. The primary work on the technologies is establishing standards for computer algorithms in iris recognition. Currently, there are three competing impage formats and three compression methods going for the international standard.

Reference: Science Daily

30 Mile Thermometer

Researchers needs to monitor the temperature of in accessible, dangerous places on the planet without using satellite data (rough estimate). The solution is using the world's largest fiber-optic cable that records temperature at three foot intervals every ten seconds. This 30 mile detector was originally designed to monitor oil wells. It functions by firing laser pulses down the length of the optical cable and photons collide within the cable and bounces back at shifted frequencies, revealing temperatures along the entire line.

Reference: Wired

Dark Matter Bolometer Detector

The existence of dark matter is induced from the behavior of faraway galaxies, which move in ways that can only be explained by a gravitational pull caused by more mass than can be seen. They estimate dark matter represents around 20 percent of the universe, with the other 75 percent made up of dark energy, a repulsive force that is causing the universe to expand at an ever-quickening pace.

Eduardo Abancens designed a prototype dark matter detector called a scintillating bolometer. It is a crystal so pure that it can conduct the energy ostensibly generated when a particle of dark matter strikes the nucleus of one of its atoms.

To prevent interference by cosmic rays, the bolometer is shielded in lead and kept half a mile underground. The challenge is to freeze the device to near-absolute zero, the temperature at which all motion stops. At the edge of absolute zero, it will possible to measure expected changes of a few millionths of a degree Fahrenheit.

Reference: “A BGO scintillating bolometer as dark matter detector prototype.” By N. Coron, E. García, J. Gironnet, J. Leblanc, P. de Marcillac, M. Martínez, Y. Ortigoza, A. Ortiz de Solórzano, C. Pobes, J. Puimedón, T. Redon, M.L. Sarsa, L. Torres and J.A. Villar. Optical Materials, Vol. 31 Issue 10, August 2009.

Artificial Nose for Detection of Toxic Gases

In the issue of Nature Chemistry, Kenneth Suslick and his team developed an artificial, digital multidimensional extension of litmus paper for general detection of toxic industrial chemicals (TICSs) in a fast, simple and inexpensive way. The device is able to give an array of concentration of colours that indicate the specific type and concentration of the toxic gas. This brings us one step closer to have small wearable sensor that can detect multiple airborne toxins.

Reference:
Lim SH, Feng L, Kemling JW, Musto CJ, Suslick KS. An Optoelectronic Nose for Detection of Toxic Gases. Nature Chemistry, 2009 DOI: 10.1038/NCHEM.360

Alternative Test To Detect DNA

Researchers in Singapore are reporting development of a new electronic "nanogap" sensor that is faster, less expensive, and more practical alternative to detect DNA. The traditional method, polymerase chain reaction (PCR), makes multiple copies of trace amounts of DNA, similar to a photocopier printing multiple copies of documents, in order to detect the genetic material more easily. However, this traditional approach is expensive and cumbersome. The "nanogap sensor" translates the presence of DNA into an electrical signal to be measured by a computer with the use of a micro-sized metal pair electrodes separated by a nanogap, 1/50,000 the width of a human hair, in combination with special chemical probes to capture tiny segments of DNA.

Reference: Science Daily

Sensitivity Infrared Spectrometry with Frequency Converter

Researchers at the National Institute of Standards and Technology (NIST) have developed a new, highly sensitive, low-cost technique for measuring light near the infrared range. A single photon detector is the key device needed to build highly sensitive instruments for measuring spectra. Their approach is adapting a technique developed two years ago at NIST for quantum cryptography that “up converts” photons at one frequency to a higher frequency. The technique promotes the infrared photons up to the visible range using a strong, tunable laser.

Reference: Science Daily

Lie Detection Method Improvement using Handwriting Tools

In the issue of Applied Cognitive Psychology, researchers utilized a computerized tablet that measured the physical properties of a person's handwriting. For instance, the duration of time that the pen is on paper and the length and height and width of each writing stroke, the pressure on the writing surface and etc. These characteristics differ when an individual is in the process of writing deceptive sentences.

Reference:
Gil Luria, Sara Rosenblum. Comparing the handwriting behaviours of true and false writing with computerized handwriting measures. Applied Cognitive Psychology, 2009; n/a DOI: 10.1002/acp.1621