Showing Spotlights 2289 - 2296 of 2424 in category All (newest first):
Some microbes are able to tolerate radioactivity and other toxic environments because they developed detoxification mechanisms that allow them to resist adverse environments without being damaged. These protective mechanisms increasingly are of great interest to scientists not only for developing innovative remediation strategies but also for creating novel biotechnological applications. As a recent example, researchers in Germany managed to produce highly stable and regular palladium (Pd) nanoparticles by harnessing the survival mechanism of bacteria found in uranium-polluted waste. These particles showed much improved catalytic activity and other new physical properties , which make them ideal for use as nanocatalysts or nanosensors.
Aug 23rd, 2006
Conventionally, the fabrication of thin film nanostructures is primarily done by using selective etching or templating growth on a prepatterned resist and then performing lift-off. The solvents used in developing resist are typically toxic and add to the cost of lithographic processing. Recently, many environmentally friendly lithographic processes have been designed using either a water-based solution or supercritical carbon dioxide to develop the resist. A novel pure water developable spin-coatable lanthanum strontium manganese oxide (LSMO) resist has been developed by scientists in Taiwan. The use of pure water instead of organic or alkaline solvents would undoubtedly be not only environmentally desirable but also could greatly simplify the imaging process.
Aug 22nd, 2006
Current production methods for carbon nanotubes result in units with different diameter, length, chirality and electronic properties, all packed together in bundles, and often blended with some amount of amorphous carbon. The separation of nanotubes according to desired properties remains a technical challenge. Especially single-walled carbon nanotube (SWCNT) sorting is a challenge because the composition and chemical properties of SWCNTs of different types are very similar, making conventional separation techniques inefficient.
Aug 21st, 2006
A number of neurodegenerative disorders, such as Parkinson's or Alzheimer Disease, may potentially be treated by gene therapy, i.e. the delivery of therapeutic genes to neurons. Currently, the most common carrier molecules to deliver the therapeutic gene to the patient's target cells are viruses that have been genetically altered to carry normal human DNA. Overall gene delivery efficiency is typically low for nonviral vectors. New research undertaken at The Johns Hopkins University offers a systematic approach to understanding the gene delivery process in neurons and explores the intracellular barriers to nonviral gene delivery and possible ways to improve their effectiveness.
Aug 18th, 2006
Researchers have developed a highly sensitive, optical bio-molecule sensor that can distinguish between bio-molecules based on the variation to the light intensity of light due to the change in the path of coupled input light. The variation to the coupled light intensity and path is dependant on the nature of the bio-molecule and the density of the bio-molecules.
Aug 17th, 2006
Individual quantum dots (QDs) have been widely investigated for the past 15 years, showing their potential applications in quantum computing. However, individual QDs are not enough for practical applications, but preparing and characterizing groups of QDs with controllable crosstalk (quantum dot molecule) is very challenging still. University of Arkansas researchers discovered a simply way to fabricate QD pairs, the most simple QD molecule. This provides a unique opportunity to study carrier interaction among QDs, one step further towards quantum computing.
Aug 16th, 2006
Encapsulating metal nanoparticles inside carbon shells is of considerable significance but fraught with high manufacturing cost due to high energy consumption and intensive use of hardware. This cost issue limits their practical applications. Researchers in China have developed a novel, simple, efficient, and economical synthesis technique for the fabrication of carbon-encapsulated nanostructures where the carbonization is conducted at a relatively low temperature of 160C in water and no toxic reagents are added. This new technique is facile and versatile, and suitable for the coating of other transition metal with carbon.
Aug 15th, 2006
A new study by Swedish researchers shows that gold nano spheres with a diameter of 7 nm, produced in a conventional laboratory surrounding, activate human antigen presenting dendritic cells (DCs) to induce proliferation of peripheral blood mononuclear cells (PBMC), mixed with either allergenic or autologous DCs. This effect was found to be due to endotoxin (lipopolysaccharide, LPS) contamination of the nanoparticles. When particles were produced in a controlled way eliminating endotoxin contamination, the activation of the DCs did not take place.
Aug 14th, 2006