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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

"You won't believe this one weird quantum mechanical trick Begonia uses!"

If I remember correctly there was a presentation at the ACT in 2014(?) about the quantum-mechanical effects essential to photosynthesis by an external speaker.

A new more efficient type of single photon light source consisting of a quantum dot reproduces 1954 Robert Dicke theoretical proposal. Applications in quantum communications directly on the target. "All light sources work by absorbing energy - for example, from an electric current - and emit energy as light. But the energy can also be lost as heat and it is therefore important that the light sources emit the light as quickly as possible, before the energy is lost as heat."

"scientists at Harvard University say they've modified the CRISPR method so it can be used to effectively reverse mutations involving changes in one letter of the genetic code. That's important because two-thirds of genetic illness in humans involve mutations where there's a change in a single letter."

"Efficient introduction of specific homozygous and heterozygous mutations using CRISPR/Cas9" http://www.nature.com/nature/journal/vaop/ncurrent/full/nature17664.html?WT.ec_id=NATURE-20160428&spMailingID=51249830&spUserID=MTEzODM0NjYzMzgS1&spJobID=903461217&spReportId=OTAzNDYxMjE3S0 As posted here previously, the number and importance of CRISPR is growing steadily, but still plenty of work to make it a reliable tool. Maybe, next work for the Molecular Engineering RF?

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

"A light-emitting diode (LED) that emits more light energy than it consumes in electrical energy has been unveiled by researchers in the US. The device - which has a conventional efficiency of greater than 200% - behaves as a kind of optical heat pump that converts lattice vibrations into infrared photons, cooling its surroundings in the process."

Sorry, did not see that you have already posted this one ...

from the abstract: "Using a novel imaging and analysis technique on experimental data we estimated pheromone concentrations at all spatial positions in the experimental arena and at different times. Then we derived the response function of individual ants to pheromone concentrations by looking at correlations between concentrations and changes in speed or direction of the ants." [...] "agent based simulations based on the Weber's Law response function determined experimentally produced results compatible with those reported in the literature and reproduced the formation of trails."

Nice article!

of relevance to this discussion: Koomey's Law, a Moore's Law equivalent for computing's energetic efficiency http://www.economist.com/node/21531350 http://hardware.slashdot.org/story/11/09/13/2148202/whither-moores-law-introducing-koomeys-law

DeSimone and his team have been working with PFPE for years, and during their research, the crew found that another polymer electrolyte, polyethylen glycol or PEG, and PFPE could combine to dissolve salt, and potentially function as an electrolyte. When his team attached the PFPE to dimethyl carbonate, an electrolyte traditionally used in batteries, the resulting PFPE-DMC was a polymer that could move a battery's ions with insane levels of efficiency while remaining stable.

The researchers used a global climate model to show that if an extreme emissions pathway -- RCP8.5 -- is followed up until 2035, allowing temperatures to rise 1°C above the 1970-1999 mean, and then SRM (Solar Radiation Management) is implemented for 25 years and suddenly stopped, global temperatures could increase by 4°C in the following decades.

Nice quantitative study. They treat the problem within the full uncertainty range of climate sensitivity parameter (much uncertain), very complete. However, at SRM ceasing, after an initial positive spike of Radiative Forcing, the rate of warming seems to return to rates predicted for the non-geoengineering case: "The 20-year temperature trends following SRM cessation are 0.2−0.6 °C/decade for the range of climate sensitivities (figure 5), comparable to those trends that occur under the RCP8.5 scenario without any SRM." I am actually working on a similar idea for deliberate Mars terraforming: aiming to cool the planet down before we introduce a positive Temperature raising feedback with greenhouse gases, maybe could be more efficient than warming itself.

Vertical windmills based on fish fins and school swimming behaviour

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

nice indeed! " Triggered by commonly available ambient mechanical energy such as human footfalls, a NG with size smaller than a human palm can generate maximum short-circuit current of 2 mA, delivering instantaneous power output of 1.2 W to external load. The power output corresponds to an area power density of 313 W/m2 and a volume power density of 54 268 W/m3 at an open-circuit voltage of 1200 V. An energy conversion efficiency of 14.9% has been achieved. The power was capable of instantaneously lighting up as many as 600 multicolor commercial LED bulbs. The record high power output for the NG is attributed to optimized structure, proper materials selection and nanoscale surface modification. This work demonstrated the practicability of using NG to harvest large-scale mechanical energy, such as footsteps, rolling wheels, wind power, and ocean waves."

You should be able to put it also in your shoes such that you may be able to power some gadgets. Thinking about it, I have seen many kids already running around with brightly lit sneakers!

a point called plasma/fuel break-even is reached where the energy released is higher than the power absorbed by the pellet. Of course, to produce 192 high power lasers does also have an efficiency. Thats why 'machine break-even' or even 'grid break-even' is more important and still quite a long way off. It does show that laser fusion is catching up quickly, although with serious bumps along the road.

I have no idea if an algorithm based on this already exists, but it would certainly be a good one for autonomous AI, I think. I think an algorithm based on this should be able to select his own input parameters and reject them if they are not stimulated any further or integrate them in the algorithm if they are continiously stimulated... this could enable self learning, etc.

By steering the neuron's back to an intermediate activity level the mechanism probably optimizes their efficiency within the network (after all a neuron that fires all the time is just as useless as one that never fires).

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.

"Could you do this? Could a spinning human slow down the Earth? Theoretically, yes." Let's all put our ice skates on and spin to enjoy a longer daytime !

Actually the length of a day fluctuates naturally. Some effects are periodic (e.g. due to seasons) while others accumulate to a general lengthening of the day (like the influence of tides): http://en.wikipedia.org/wiki/Fluctuations_in_the_length_of_day

Is it not more efficient to just all start running eastward? We could have a new "Jump Day" frenzy :)