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A North Carolina State University researcher has developed a more efficient, less expensive way of cooling electronic devices - particularly devices that generate a lot of heat, such as lasers and power devices.

Cheap and scalable invisibility cloaks being developed. The setup is so trivial that I would almost call it a "trick" (as in "Magicians trick"): 6 prisms of n=1.78 glass. Nontheless, it does the job of cloaking an object at visible wavelengths and from several directions.

Is this really new? I don't know, but I know that the original idea of cloaking was pretty different. When cloaking as an application of transformation optics became popular people tried to make devices that work for any incidence angle, any polarization and in full wave optics (not just ray approximation). This is really hard to achieve and I guess that the people that tried to make such devices knew exactly that the task becomes almost trivial by dropping at least two of the three conditions above.

I think it is very easy to call something trivial when you're not the one who invested considerable time (5 min in my case) to design a cloaking device and fill the coffee mugs with water... Also, I did not really violate that many conditions: true I reduced the number of dimensions in which the device works to 1 (as opposed to the 2 dimensions of many metamaterial cloaks). However the polarization should not be affected in my setup as well as the wave phase and wave vector (so it works in full wave optics) - apart maybe from the imperfect lens distortion, but hey I was improvising.

"...scientists in Germany have built a device that can effectively make objects invisible to sound waves. The performance of the acoustic "invisibility cloak" exceeds that of existing electromagnetic devices and could open up new ways of manipulating waves, including the development of shields against seismic waves."

shit.... they are a few months ahead of us it seems ... :-( what is the impact on our ariadna??

"I don't have a cell phone. I won't carry a cell phone," says Stallman, founder of the free software movement and creator of the GNU operating system. "It's Stalin's dream. Cell phones are tools of Big Brother. I'm not going to carry a tracking device that records where I go all the time, and I'm not going to carry a surveillance device that can be turned on to eavesdrop." he is right once more ...

I am going to live in the forest! Sadly, while true, there's no way around it these days. On the up-side the information overflow these days exceeds processing speeds. Soon it will become increasingly difficult for NSA or other organizations to find anything in the tons of data they stash away. Like some guy said in a random youtube video I can't find now anymore: "good luck trying to find my personal data when I'm tagged in 5000 pictures of cats!"

Very interesting work, showing that apparently algae mastered quantum coherence a few years before us... Inspiring for a new type of light-sensitive devices, and perhaps other applications...

Baratunde Cola would like to put sand into your computer. Not beach sand, but silicon dioxide nanoparticles coated with a high dielectric constant polymer to inexpensively provide improved cooling for increasingly power-hungry electronic devices. The silicon dioxide doesn't do the cooling itself.

Old news... Sante was doing this 10 years ago! And why does their metamaterial look like a pyramid?

According to Terry Pratchett pyramids affect the flow of time. Using this, any kind of cloaking device should be trivial.

Using little more than a few perforated sheets of plastic and a staggering amount of number crunching, Duke engineers have demonstrated the world's first three-dimensional acoustic cloak. The new device reroutes sound waves to create the impression that both the cloak and anything beneath it are not there.

The device, like dolphins, sends out two pulses in quick succession to allow for a targeted search for semiconductor devices, cancelling any background "noise",

Could it be used to measure ocean acidification? I found a study that links sound wave propagation with ocean acidity. Maybe we are able to do such measurement from space even? "Their paper, "Unanticipated consequences of ocean acidification: A noisier ocean at lower pH," published last week in the journal Geophysical Research Letters, found that fossil fuels are turning up the ocean's volume. Since the beginning of the Industrial Revolution, the overall pH of the world's oceans has dropped by about 0.1 units, with more of the changes concentrated closer to the poles. The authors found that sound absorption has decreased by 15 percent in parts of the North Atlantic and by 10 percent throughout the Atlantic and Pacific"

The last time I asked an oceanographer for the use of acoustic waves, she said it is still a bit problematic method to take into account its data, but we were referring to measuring ocean circulation. It may be more conclusive for PH measurements, though. The truth is that there is a whole underwater network with pulse emmitters/receivers covering the North Atlantic basin, remnant infrastructure for spying activities in the WW2 and in the cold war, that stays unexploited. We should look more into this idea

article written a bit as if they had invented rectennas ... they are used since the 60s (Brown powered a small helicopter via 2.45 GHz ... and Kaya-san has showed wireless power transmission via advanced rectenna's at almost every SPS conference since 20 years ...

Droplets can be made to chase each other around a track and even self-assemble into devices, simply by mixing two everyday liquids. This remarkable discovery made by scientists in the US has already been used to create beautiful shapes and patterns, and could also be exploited to create optical components that assemble themselves and even to clean surfaces. It looks very like Jojo's self-assembling balls :p

5.8 GHz wireless power transmission for mainstream gadgets ...

Proximity to the transmitter impacts power delivery as follows: 4W delivered to 4 devices simultaneously within 0-5 feet 2W delivered to 4 devices simultaneously within 5-10 feet 1W delivered to 4 devices simultaneously within 10-15 feet How to make a piecewise approximation of one inverse square law for commercial purposes

:-) - which also tells us that these are not measured values but estimations it seems to me ...

looks like some backwind for all the cold fusion believers ...

I just answered something very similar to Franco, except the conclusions: I don't think that there is a good reason for us or anybody else in ESA to get involved at this stage.

I agree - if this device would work it there would be other interest groups (like the energy sector) with a much more concrete stake in the technology.

"Her goal was to design and synthesise a super capacitor with increased energy density while maintaining power density and long cycle life. She designed, synthesised and characterised a novel core-shell nanorod electrode with hydrogemated TiO2(H-TiO2) core and polyaniline shell. H-TiO2 acts as the double layer electrostatic core. Good conductivity of H-TiO2 combined with the high pseudo capacitance of polyaniline results in significantly higher overall capacitance and energy density while retaining good power density and cycle life. This new electrode was fabricated into a flexible solid-state device to light an LED to test it in a practical application. Khare then evaluated the structural and electrochemical properties of the new electrode. It demonstrated high capacitance of 203.3 mF/cm2 (238.5 F/g) compared to the next best alternative super capacitor in previous research of 80 F/g, due to the design of the core-shell structure. This resulted in excellent energy density of 20.1 Wh/kg, comparable to batteries, while maintaining a high power density of 20540 W/kg. It also demonstrated a much higher cycle life compared to batteries, with a low 32.5% capacitance loss over 10,000 cycles at a high scan rate of 200 mV/s."

NASAs new Exoskeleton! It is supposed to be a fitness device for Astronauts which can also be used in combination with a space suit on missions.

In Israel, a new way to hack by turning speakers into microphones.

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.

Researchers in the US have made a "carpet cloak" that makes objects invisible to sound waves. The device is the first such cloak to work in air and could be used to improve the acoustics in concert halls or even to control unwanted noise.

Researchers at the University of Toronto in Canada and KAUST in Saudi Arabia have made a solar cell out of colloidal quantum dot (CQD) films that has a record-breaking efficiency of 7%. This is almost 40% more efficient than the best previous devices based on CQDs.

All patents violated by Samsung!!! I wonder if Apple patented also the use of eyes when interacting electronic devices :)