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Nonradiative resonant energy transfer in optimized QD-QW systems may provide a solar energy conversion approach with a viable tradeoff with the bottlenecks of charge carrier generation and/or transport to/in electrodes faced by excitonic solar cells.

I think there are a few difficulties when assuming that the macroscopic block of glass will accelerate instantaneously. Also, if I prevent the block from moving would it become perfectly reflective as no momentum can be transferred to it? One could say that the momentum is then transferred to the larger system that holds the glass. But surely I could make that system (or even the block of glass) so heavy that it would not move more than Planck's length during the passage of the photon - especially if the glass is very thin or the light is very red.

Apple apparently interested in exactly the type of wireless power transfer we were looking into with Duncan and Xurxo!

Old post from Luis brought back from graveyard..... At least two good ideas to put there: 1) tipping points prediction 2) planetary phases for trajectory transfer and probably many more if we think about it a bit more

In a first-of-its-kind study, an international team of neuroscientists and robotics engineers has demonstrated the viability of direct brain-to-brain communication in humans.

Was just about to post it... :) It seems after transferring the EEG signals of one person, converting it to bits and stimulating some brain activity using magnetic stimulation (TMS) the receiving person actually sees 'flashes of light' in their peripheral vision. So its using your vision sense to get the information across. Would it not be better to try to see if you can generate some kind of signal in the part of your brain that is connected to 'hearing'? Or would this be me thinking too naive?

"transferring the EEG signals of one person, converting it to bits and stimulating some brain activity using magnetic stimulation (TMS)" How is this "direct"?

The principle behind that is Nantenna.

this is fantastic!!!! waiting of somebody to make this happen since years The size of the gap is critical because it creates an ultra-fast tunnel junction between the rectenna's two electrodes, allowing a maximum transfer of electricity. The nanosized gap gives energized electrons on the rectenna just enough time to tunnel to the opposite electrode before their electrical current reverses and they try to go back. The triangular tip of the rectenna makes it hard for the electrons to reverse direction, thus capturing the energy and rectifying it to a unidirectional current. Impressively, the rectennas, because of their extremely small and fast tunnel diodes, are capable of converting solar radiation in the infrared region through the extremely fast and short wavelengths of visible light - something that has never been accomplished before. Silicon solar panels, by comparison, have a single band gap which, loosely speaking, allows the panel to convert electromagnetic radiation efficiently at only one small portion of the solar spectrum. The rectenna devices don't rely on a band gap and may be tuned to harvest light over the whole solar spectrum, creating maximum efficiency. Through atomic layer deposition, Willis has shown he is able to precisely coat the tip of the rectenna with layers of individual copper atoms until a gap of about 1.5 nanometers is achieved. The process is self-limiting and stops at 1.5 nanometer separation The size of the gap is critical because it creates an ultra-fast tunnel junction between the rectenna's two electrodes, allowing a maximum transfer of electricity. The nanosized gap gives energized electrons on the rectenna just enough time to tunnel to the opposite electrode before their electrical current reverses and they try to go back. The triangular tip of the rectenna makes it hard for the electrons to reverse direction, thus capturing the energy and rectifying it to a unidirectional current. Impressively, the rectennas, because of th

"Patents, licensing practices and technology transfer from rich to poor countries are major issues in the fight against climate change," says Ahmed Abdel Latif, the programme manager for intellectual property at the International Centre for Trade and Sustainable Development

The vibrissae of rats (et al) are examined and transferred to robotic devices for orientation and tactile exploration.

Finish him!

38 degree core body temp in microgravity stabilised after 2 months - due to reduced conv. heat transfer+evaporation https://www.nature.com/articles/s41598-017-15560-w

so that's hypopyrexia (augmented concentrations of interleukin-1 receptor antagonist) AND hypothermia (convection/evaportation)? what puzzles me is that temperatures take so long to return to baseline after astronauts return to earth.

Collaborative technology transfer.. sounds like something the Advanced Concepts Generator should have come up with..

Bacterial wires explain enigmatic electric currents in the seabed: Each one of these 'cable bacteria' contains a bundle of insulated wires that conduct an electric current from one end to the other. Cable bacteria explain electric currents in the seabed Electricity and seawater are usually a bad mix.

WOW!!!! don't want to even imagine what we do to these with the trailing fishing boats that sweep through sea beds with large masses .... "Our experiments showed that the electric connections in the seabed must be solid structures built by bacteria," says PhD student Christian Pfeffer, Aarhus University. He could interrupt the electric currents by pulling a thin wire horizontally through the seafloor. Just as when an excavator cuts our electric cables. In microscopes, scientists found a hitherto unknown type of long, multi-cellular bacteria that was always present when scientists measured the electric currents. "The incredible idea that these bacteria should be electric cables really fell into place when, inside the bacteria, we saw wire-like strings enclosed by a membrane," says Nils Risgaard-Petersen, Aarhus University. Kilometers of living cables The bacterium is one hundred times thinner than a hair and the whole bacterium functions as an electric cable with a number of insulated wires within it. Quite similar to the electric cables we know from our daily lives. "Such unique insulated biological wires seem simple but with incredible complexity at nanoscale," says PhD student Jie Song, Aarhus University, who used nanotools to map the electrical properties of the cable bacteria. In an undisturbed seabed more than tens of thousands kilometers cable bacteria live under a single square meter seabed. The ability to conduct an electric current gives cable bacteria such large benefits that it conquers much of the energy from decomposition processes in the seabed. Unlike all other known forms of life, cable bacteria maintain an efficient combustion down in the oxygen-free part of the seabed. It only requires that one end of the individual reaches the oxygen which the seawater provides to the top millimeters of the seabed. The combustion is a transfer of the electrons of the food to oxygen which the bacterial inner wires manage over centimeter-long distances. However, s

Put together two ACT topics and see what happens.

I remember discussing this briefly and then discarding the idea - but don't remember why any more; duncan?

Well, I think that although the antenna is small, you counteract this with a much large metameterial lens. Probably if you design an antenna of a similar size to the 'lens' you can couple power equally well over the same distance. Then again, further optimization might help improve the size. Maybe in the end you want to combine both together, optimization of the antenna, including a metamaterials lens.

Another underestimated source of CO2, are turbulent waters. "The stronger the turbulences at the water's surface, the more CO2 is released into the atmosphere. The combination of maps and data revealed that, while the CO2 emissions from lakes and reservoirs are lower than assumed, those from rivers and streams are three times as high as previously believed." Alltogether the emitted CO2 equates to roughly one-fifth of the emissions caused by humans. Yet more stuff to model...

Nasia, I thought about your statement carefully - and I cannot agree with you. Water is not a greenhouse gas. It is instead a liquid. Also, I can't believe you keep feeding the troll! :-P But on a more topical note: I think it is an over-simplification to call water a greenhouse gas - water is one of the most important mechanisms in the way Earth handles heat input from the sun. The latent heat that you mention actually cools Earth: solar energy that would otherwise heat Earth's surface is ABSORBED as latent heat by water which consequently evaporates - the same water condenses into rain drops at high altitudes and releases this stored heat. In effect the water cycle is a mechanism of heat transport from low altitude to high altitude where the chance of infrared radiation escaping into space is much higher due to the much thinner layer of atmosphere above (including the smaller abundance of greenhouse gasses). Also, as I know you are well aware, the cloud cover that results from water condensation in the troposphere dramatically increases albedo which has a cooling effect on climate. Furthermore the heat capacity of wet air ("humid heat") is much larger than that of dry air - so any advective heat transfer due to air currents is more efficient in wet air - transporting heat from warm areas to a natural heat sink e.g. polar regions. Of course there are also climate heating effects of water like the absorption of IR radiation. But I stand by my statement (as defended in the above) that rain cools the atmosphere. Oh and also some nice reading material on the complexities related to climate feedback due to sea surface temperature: http://journals.ametsoc.org/doi/abs/10.1175/1520-0442(1993)006%3C2049%3ALSEOTR%3E2.0.CO%3B2

I enjoy trolling conversations when there is a gain for both sides at the end :-) . I had to check upon some of the facts in order to explain my self properly. The IPCC report states the greenhouse gases here, and water vapour is included: http://www.ipcc.ch/publications_and_data/ar4/wg1/en/faq-2-1.html Honestly, I read only the abstract of the article you posted, which is a very interesting hypothesis on the mechanism of regulating sea surface temperature, but it is very localized to the tropics (vivid convection, storms) a region of which I have very little expertise, and is difficult to study because it has non-hydrostatic dynamics. The only thing I can comment there is that the authors define constant relative humidity for the bottom layer, supplied by the oceanic surface, which limits the implementation of the concept on other earth regions. Also, we may confuse during the conversation the greenhouse gas with the Radiative Forcing of each greenhouse gas: I see your point of the latent heat trapped in the water vapour, and I agree, but the effect of the water is that it traps even as latent heat an amount of LR that would otherwise escape back to space. That is the greenhouse gas identity and an image to see the absorption bands in the atmosphere and how important the water is, without vain authority-based arguments that miss the explanation in the end: http://www.google.nl/imgres?imgurl=http://www.solarchords.com/uploaded/82/87-33833-450015_44absorbspec.gif&imgrefurl=http://www.solarchords.com/agw-science/4/greenhouse--1-radiation/33784/&h=468&w=458&sz=28&tbnid=x2NtfKh5OPM7lM:&tbnh=98&tbnw=96&zoom=1&usg=__KldteWbV19nVPbbsC4jsOgzCK6E=&docid=cMRZ9f22jbtYPM&sa=X&ei=SwynUq2TMqiS0QXVq4C4Aw&ved=0CDkQ9QEwAw

Never knew they could paint this way

Does this have implications for AI algorithms??

I was actually thinking exactly about this question during my bike ride this morning. I am surprised that some codons would need to have a double meaning though because there is already a surplus of codons to translate into just 20-22 proteins (depending on organism). So there should be about 44 codons left to prevent translation errors and in addition regulate gene expression. If - as the article suggests - a single codon can take a dual role, does it so in different situations (needing some other regulator do discern those)? Or does it just perform two functions that always need to happen simultaneously? I tried to learn more from the underlying paper: https://www.sciencemag.org/content/342/6164/1367.full.pdf All I got from that was a headache. :-\

Probably both. Likely a consequence of energy preservation during translation. If you can do the same thing with less genes you save up on the effort required to reproduce. Also I suspect it has something to do with modularity. It makes sense that the gene regulating for "foot" cells also trigger the genes that generate "toe" cells for example. No point in having an extra if statement.

Known technically as a surface plasmon polariton (SPP) wave, the effect will allow the nano-antennas to operate at the low end of the terahertz frequency range, between 0.1 and 10 terahertz - instead of at 150 terahertz With this antenna, we can cut the frequency by two orders of magnitude and cut the power needs by four orders of magnitude," said Jornet. "Using this antenna, we believe the energy-harvesting techniques developed by Dr. Wang would give us enough power to create a communications link between nanomachines." As always, graphene seems to be the answer to anything, but steady progress is being made although one needs to find out first an easy method of generating high quality graphene layers (btw that is also one of the reasons to do the supercapacitor study...)

Well plasmonics is also the solution to everything it seems...

Basically quantum entanglement, or more accurately the dispersal and expansion of mixed quantum states, results in an apparent flow of time. Quantum information leaks out and the result is the move from a pure state (hot coffee) to a mixed state (cooled down) in which equilibrium is reached. Theoretically it is possible to get back to a pure state (coffee spontaneously heating up) but this statistical unlikelihood gives the appereance of irreversibility and hence a flow o time. I think an interesting question is then: how much useful work can you extract from this system? (http://arxiv.org/abs/1302.2811) It should for macroscopic thermodynamic systems lead to the Carnot cycle, but on smaller scales it might be possible to formulate a more general expression. Anybody interested to look into it? Anna, Jo? :)

What you propose is called Maxwell's demon: http://en.wikipedia.org/wiki/Maxwell%27s_demon Unfortunately (or maybe fortunately) thermodynamics is VERY robust. I guess if you really only want to harness AND USE the energy in a microscopic system you might have some chance of beating Carnot. But any way of transferring harvested energy to a macroscopic system seems to be limited by it (AFAIK).

wireless power transmission made useful ? this application did certainly not come to my mind when Guy Pignolet showed me 12 years ago how his handy would lid up a small diode after our first SPS meeting in Paris ...

Great idea to use either unused/wasted energy. Then again, the signal power (receiver floor) is steadily going down going from 3G to 5G, yet there might be more use of bandwidth to compensate this. It is funny though that you buy a device which could have the function build in it on the back from the start, yet you put a shell around it and then harness wireless power to give it that add-on functionality.

Recently I came across this article in a Japanese newspaper about wireless power transmission applications in the women beauty business. It's probably not as useful as an iPhone cover but apparently there is a market for such things! http://www.japantimes.co.jp/news/2014/04/18/business/led-nails-light-up-when-calling/#.U2OcWV7v2X8