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Researchers at Tohoku University have, for the first time, successfully demonstrated the basic operation of spintronics-based artificial neural network.

It is typically considered that brain's process of learning is highly energy efficient. While investigating how efficiently the brain can learn new information, physicists have found that, at the neuronal level, learning efficiency is ultimately limited by the laws of thermodynamics.

Although vacuum tubes were the basic components of early electronic devices, by the 1970s they were almost entirely replaced by semiconductor transistors. They are now back in nano-form as "nanoscale vacuum channel transistors" that combine the best of vacuum tubes and modern semiconductors into a single device. This old-technology with a new twist could be useful for space applications due to broader temperature operational range and better radiation resilience - authors are with NASA Ames.

... no comment...

Interesting. these guys are apparently gonna try developing pulsar navigation. They propose to solve the low apparent brightness problem using relatively complex signal processing and filtering to limit the antenna size etc. The say they've already had some promising results using ground based data. worth a science coffee perhaps?

Absolutely. Sante can you get in contact with them?

"... scientists at the Technical University of Delft in the Netherlands yesterday published their findings that they have indeed found the Majorana particle. The announcement on the university website provides both a summary of the ..." Also see: http://tudelft.nl/en/current/latest-news/article/detail/nanowetenschappers-vinden-langgezocht-majorana-deeltje/

This is the first time that significant pair production has been demonstrated in a structure that can be electrically self-pumped and which can form the basis for passive optical circuitry, bringing us markedly closer to complete integration of quantum optical technologies.

"One of the leading theories describing how the most energetic cosmic rays are produced may need a rethink in light of a new study by physicists at the IceCube Neutrino Observatory in Antarctica. The team had set out to detect the extremely energetic neutrinos that are expected to be produced alongside high-energy cosmic rays in the violent explosions that mark the deaths of massive stars - but after looking at hundreds of these explosions, no such neutrinos have been found. "

news from the Sabre engine ...

Researchers in the US have built a new type of solar cell that emits light as well as absorbs it, making it the most efficient solar cell ever developed. The efficiency of their prototype cell allows it to convert 28.6% of the Sun's energy into electricity.

well, the text is at best misleading ... the most efficient solar cells are well over 35% and approach the 40s with concentration! what they have done is to increase the limit of a single junction cell it seems to me ... still, nteresting though from text most details on how this was done are missing ... paper is not yet published, correct?

I learn of it in a workshop few weaks ago. It's on GaAs and I think that the key theoretical aspects are explained here: http://arxiv.org/abs/1106.1603

The ability to teleport photons through 100 kilometres of free space opens the way for satellite-based quantum communications, say researchers

Metamaterials that absorb seismic waves rather than steer them, might be a better way to protect some buildings, say engineers

what are seismic metamaterials?

must look funny ... They calculate the properties of such a metatmaterial and how it might be constructed with a basic repeating unit in the form of a concrete cylinder some 18 metres in diameter, with four perpendicular holes in its sides (see picture). These cylinders, perhaps varying in size to absorb a range of seismic wavelengths, would need to surround the foundations of a building in cylindrical shells some 60 metres across. That needn't be prohibitively expensive but it would be a big structure that could only be constructed around isolated buildings (thereby somewhat negating the supposed benefit that other buildings in the earthquake 'shadow' might also be protected).

so what about a space sensor for measuring thermal efficiency of buildings? Can you have a look ?

...obvious use for space...

Indeed, you only need ONE antenna to communicate with your satellite irrespective of its position, since one can freely send the signals right through the Earth. Small disadvantage: you should tell the launcher section to design a new launcher that is capable to bring a 200tons detector to space...

Researchers in the US have created the first artificial samples of graphene with electronic properties that can be controlled in a way not possible in the natural form of the material.

The end is near...

che brutta figura ...

Some quotes: "Our results are in agreement with what Einstein would like to have" - they called him just to double-check... "How many times do you have to say 'zero' to make sure it's zero?" - because statistics is just not trendy any more...

:D  so that's why the ACT recycles physicists every 2 years !!