Nanoparticles may help prevent tooth decay

                Scientists have found a way to use nano-particles to effectively break down plaque and wipe out more than 99.9% of cavity-causing bacteria within minutes, an advance that may help better prevent tooth decay. The bacteria that live in dental plaque and contribute to tooth decay often resist traditional antimicrobial treatment, as they can “hide” within a sticky bio-film matrix, a glue-like polymer scaffold.

                Researchers at University of Pennsylvania took a more sophisticated approach. Instead of applying an antimicrobial to the teeth, they took advantage of the pH-sensitive and enzyme-like properties of iron-containing nano-particles to catalyse the activity of hydrogen peroxide, a commonly used natural antiseptic.

                The activity hydrogen peroxide produced free radicals that were able to degrade the bio-film matrix and kill the bacteria within, significantly reducing plaque and preventing the tooth decay, or cavities, in an animal model. “Even using a very low concentration of hydrogen peroxide, the process was incredibly effective at disrupting the bio-film,” said Hyun Koo, from the University of Pennsylvania. “Adding nano-particles increased the efficiency of bacterial killing more than 5,000 fold,” said Koo.

                Previous research showed that iron oxide nano-particles behave similarly to a peroxidase, an enzyme found naturally that catalyses oxidative reactions, often using hydrogen peroxide.

China launches Yaogan-30 remote sensing satellite

                On 15 May 2016, China launched the Yaogan-30 remote sensing satellite. It was placed in the sun-synchronous orbit (SSO) by using the Long March 2-D rocket. The Satellite was launched from Jiuquan Satellite Launch Canter located in Gobi desert in Northwest China’s Gansu Province.

Key Features:

•          It will be used for scientific experiments, land survey, crop yield assessment and disaster monitoring.
•          It has high resolution optical sensors that have a resolution of between one to three meters.
•          The satellite was placed in the SSP so that it provides favorable illumination for the imaging missions.
•          It has two deployable solar arrays along with batteries. It uses the CAST-2000 platform, which has a dry mass of about one metric ton.
•          The first satellite in the Yaogan series, Yaogan-1, was launched in 2006.

Computer that roll up like paper in the offing

                Ultrathin an lightweight computers that roll up like a piece of paper may be closer to reality, thanks to highly flexible organic light-emitting diodes (OLEDs) developed by Korean scientists. The OLEDs have excellent efficiency and make use of graphene as a transparent electrode. OLEDs, built upon a plastic substrate, have received greater attention lately for their use in next-generation displays that can be bent or rolled while still operating.

                Researchers led by Seunghyup Yoo from Korea Advanced Institute of Science and Tae-Woo Lee from Pohang University of Science and Technology in South Korea used graphene as a transparent electrode (TE) which is placed in between titanium dioxide (TiO₂) and conducting polymer layers. This is an optical design that induces a synergistic collaboration between the high-n and low-n layers to increase the effective reflectance of TEs. Under this approach, graphene-based OLED devices remain intact and operate well even after 1,000 bending cycles at a radius of curvature as small as 2.3mm.

Invisible cloak closer to reality

In a first, scientists made an object disappear by using a composite material that can enhance an object’s surface properties, an advance that may lead to practical invisibility cloaks. Researchers at Queen Mary University of London School of Electronic Engineering and Computer Science, presented a cloaking device that allows curved surfaces to appear flat to electromagnetic waves. The design is based on transformation optics, a concept behind the idea of the invisibility cloak.