Quantum Dot White LEDs achieve Record Efficiency

Researchers created nanomaterial-based white LEDs that exhibit a record high efficiency thanks to quantum dots that are suspended in solution rather than embedded in a solid. The new LEDs could offer an energy-efficient lighting source for homes, offices and televisions. Credit: Sedat Nizamoglu, Koç University

Researchers created nanomaterial-based white LEDs that exhibit a record high efficiency thanks to quantum dots that are suspended in solution rather than embedded in a solid. The new LEDs could offer an energy-efficient lighting source for homes, offices and televisions.
Credit: Sedat Nizamoglu, Koç University

Novel approach to white LEDs could lead to more energy-efficient lighting. Researchers have demonstrated nanomaterial-based white-light-emitting diodes (LEDs) that exhibit a record luminous efficiency of 105 lumens per watt. Luminous efficiency is a measure of how well a light source uses power to generate light...

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Hubble and Gaia team up to fuel Cosmic Conundrum

Using two of the world's most powerful space telescopes -- NASA's Hubble and ESA's Gaia -- astronomers have made the most precise measurements to date of the universe's expansion rate. This is calculated by gauging the distances between nearby galaxies using special types of stars called Cepheid variables as cosmic yardsticks. By comparing their intrinsic brightness as measured by Hubble, with their apparent brightness as seen from Earth, scientists can calculate their distances. Gaia further refines this yardstick by geometrically measuring the distances to Cepheid variables within our Milky Way galaxy. This allowed astronomers to more precisely calibrate the distances to Cepheids that are seen in outside galaxies. Credit: NASA, ESA, and A. Feild (STScI)

Using two of the world’s most powerful space telescopes — NASA’s Hubble and ESA’s Gaia — astronomers have made the most precise measurements to date of the universe’s expansion rate. This is calculated by gauging the distances between nearby galaxies using special types of stars called Cepheid variables as cosmic yardsticks. By comparing their intrinsic brightness as measured by Hubble, with their apparent brightness as seen from Earth, scientists can calculate their distances. Gaia further refines this yardstick by geometrically measuring the distances to Cepheid variables within our Milky Way galaxy. This allowed astronomers to more precisely calibrate the distances to Cepheids that are seen in outside galaxies. Credit: NASA, ESA, and A. Feild (STScI)

Using the power and synergy of two s...

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Scientists create Nano-size packets of Genetic Code aimed at Brain Cancer ‘Seed’ Cells

Nanoparticles releasing microRNAs (light blue) inside a human brain cancer cell. Credit: Yuan Rui, Johns Hopkins

Nanoparticles releasing microRNAs (light blue) inside a human brain cancer cell. Credit: Yuan Rui, Johns Hopkins

In a “proof of concept” study, scientists at Johns Hopkins Medicine say they have successfully delivered nano-size packets of genetic code called microRNAs to treat human brain tumors implanted in mice. The contents of the super-small containers were designed to target cancer stem cells, a kind of cellular “seed” that produces countless progeny and is a relentless barrier to ridding the brain of malignant cells.

Results of their experiments were published online June 21 in Nano Letters. “Brain cancer is one of the most widely understood cancers in terms of its genetic makeup, but we have yet to develop a good treatment for it,” says John Laterra, M.D., Ph.D...

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Breakthrough in the Search for Cosmic Particle Accelerators

Artist's impression of the active galactic nucleus. The supermassive black hole at the center of the accretion disk sends a narrow high-energy jet of matter into space, perpendicular to the disc. Credit: DESY, Science Communication Lab

Artist’s impression of the active galactic nucleus. The supermassive black hole at the center of the accretion disk sends a narrow high-energy jet of matter into space, perpendicular to the disc. Credit: DESY, Science Communication Lab

Scientists trace a single neutrino back to a galaxy billions of light years away. Using an internationally organised astronomical dragnet, scientist have for the first time located a source of high-energy cosmic neutrinos, that travel billions of light years through the universe, flying unaffected through stars, planets and entire galaxies. The joint observation campaign was triggered by a single neutrino that had been recorded by the IceCube neutrino telescope at the South Pole, on 22 September 2017...

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