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Useful tool for managment

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.

Carrier multiplication (CM) is a process in which absorption of a single photon produces not just one but multiple electron-hole pairs. This effect is a potential enabler of next-generation, high-efficiency photovoltaic and photocatalytic systems.

The ability of living organisms to generate light by bioluminescence is a fascinating phenomenon. Nature Photonics spoke to Yoriko Ando from the University of Tokyo about her recent quantitative analysis of the effect in fireflies.

nice concept - still have to look closer into it ...

Open source general mission analysis software. Should we be in as developers?

We show numerically that vector antenna arrays can generate radio beams that exhibit spin and orbital angular momentum characteristics similar to those of helical Laguerre-Gauss laser beams in paraxial optics. For low frequencies (<~1 GHz), digital techni

General Education links for Africa

General information of Africa countries. List of African Universities

NASA should use social media to make generation Y interested in space

Artificial cells could be built that not only replicate the electrical behavior of electric eel cells but in fact improve on them. Artificial versions of the eel's electricity generating cells could be developed as a power source for medical implants and

Maglev) wind power generator

Apparently, the generation growing up with internet (native digital) will be living and working in a completely different way. ESA might have to adapt.

Luca and Tobias - have a look at this ... LS

"C++ is a horrible language. It's made more horrible by the fact that a lot of substandard programmers use it, to the point where it's much much easier to generate total and utter crap with it."

new article about Japanese SPS plans ... in general all that is written is actually also true ....

Physicists have exploited the laws of quantum mechanics to generate random numbers on a Nokia N9 smartphone, a breakthrough that could have major implications for information security

Jeremy England, a 31-year-old assistant professor at the Massachusetts Institute of Technology, has derived a mathematical formula that he believes explains this capacity. The formula, based on established physics, indicates that when a group of atoms is driven by an external source of energy (like the sun or chemical fuel) and surrounded by a heat bath (like the ocean or atmosphere), it will often gradually restructure itself in order to dissipate increasingly more energy. This could mean that under certain conditions, matter inexorably acquires the key physical attribute associated with life. The simulation results made me think of Jojo's attempts to make a self-assembling space structure. Seems he may have been on the right track, just not thinking big enough

:-P Thanks Thijs... I do not agree with the premise of the article that a possible correlation of energy dissipation in living systems and their fitness means that one is the cause for the other - it may just be that both go hand-in-hand because of the nature of the world that we live in. Maybe there is such a drive for pre-biotic systems (like crystals and amino acids), but once life as we know it exists (i.e., heredity + mutation) it is hard to see the need for an amendment of Darwin's principles. The following just misses the essence of Darwin: "If England's approach stands up to more testing, it could further liberate biologists from seeking a Darwinian explanation for every adaptation and allow them to think more generally in terms of dissipation-driven organization. They might find, for example, that "the reason that an organism shows characteristic X rather than Y may not be because X is more fit than Y, but because physical constraints make it easier for X to evolve than for Y to evolve." Darwin's principle in its simplest expression just says that if a genome is more effective at reproducing it is more likely to dominate the next generation. The beauty of it is that there is NO need for a steering mechanism (like maximize energy dissipation) any random set of mutations will still lead to an increase of reproductive effectiveness. BTW: what does "better at dissipating energy" even mean? If I run around all the time I will have more babies? Most species that prove to be very successful end up being very good at conserving energy: trees, turtles, worms. Even complexity of an organism is not a recipe for evolutionary success: jellyfish have been successful for hundreds of millions of years while polar bears are seem to be on the way out.

Good news for fundamental physics and Earth system science, femtosecond lasers are now about to achieve space qualification thanks to fibre optics!  Applications include high resolution spectroscopy, absolute laser ranging, mapping of the geo-potential and testing of the theory of general relativity to name a few!

nice paper by the Koreans, did not know that they had already such a laser in orbit for a year. How much would this type be upscalable for our needs? in case we have not, we should reference it