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Comment Re:Power density? (Score 1) 78

The total heat produced by radioactivity in Earth is 44.2 TW (Wikipedia).
The total solar power received by Earth by the upper atmosphere is 174 PW (Wikipedia).
This means 3937 more solar energy is received by Earth than produced by radioactivity in its interior.
Furthermore geothermal energy is high entropy energy in regard of solar energy since the temperature difference between
ground (~287K) and nearby space (>10K) (DT=277K) is much less than the temperature difference between
sunlight (5778K) and ground (DT=5491K).

In short the whole idea of converting Earth heat into electricity is completely inefficient in regard of solar energy.
The only way to use efficiently geothermal energy is to find hot spots where it is concentrated by thousands with respect to average.

Comment Re:I call BS (Score 3, Informative) 71

63x total coverage with from Illumina hardware using a mixture of paired-end libraries, ranging from 200 bp to a whopping 40 Kbp. I'm pretty sure that's sufficient information to estimate the number of large-scale repetitions. Sequencing projects of species for which there is no good relative to scaffold against are typically much more rigorous than what you'd see in cancer research.

Comment Re:I'm Inferior To A Tree (Score 5, Interesting) 71

While the set of large-genomed organisms does include some very sophisticated trees and flowers, it also includes several species of amoeba... so I wouldn't panic just yet.

All a big genome really means for certain is that you're good enough at finding food that you can support it. The substance is a lot more important—some species of shrimp, for example, have 88 or 92 chromosomes, but they're mostly redundant duplicates. Wheat has five copies of every chromosome, too.

Plants tend to have large genomes because they reproduce so rapidly—a field of corn has enough offspring every season to mutate every nucleotide in the whole kit and kaboodle at least once, and because they have very static, slow existences, they can afford to tune themselves very well to their environments. That's what the genes and duplicates are for—giving the plant very fine-grained control over things like how it prepares for the next season based on the weather from the last one.

Comment Re:Beta testers (Score 5, Interesting) 91

You can create a file system on a file on your disk (similar to a swap file).
Contrary to popular believe this is not slower than a partition, because if the file is mostly continuous, it can be mapped to disk directly by the kernel. Here I create a file system using a sparse file:
$ truncate +20G mylocal.fs
$ mkfs.btrfs mylocal.fs
$ mkdir -p mylocal; sudo mount mylocal.fs mylocal/

You can use such file systems, for example, to bundle directories with many files, which are deleted/created many times. This causes fragmentation in the file system. Contrary to another popular believe, yes, this is a problem on Linux file systems, and it slows down reads. None of the file system currently has a defragger implemented. Btrfs is actually developing one, but I think it is not in the release yet. The recommended solution is rewriting files (shake).

Sub file system containers can be easily resized, and with sparse files only use up the space filled with data. I use them for the linux kernel build directory (you shouldn't build in /usr/src), for portage (many files, changing frequently), and scientific data directories, to limit the fragmentation, and keep speed high. I use reiserfs for this -- find a managing script here: https://github.com/JohannesBuc...

Comment Re:Fortunately for Jobs (Score 3, Funny) 129

If it were GPL, every recipient would be required to pass his organs on upon his death. And the organ would perpetually be passed on, because organs want to be free.

Actually not just the organ he received, but all his organs, because the other components require the one received. Although I guess you can argue a generic API.

Hardware Hacking

Is DIY Brainhacking Safe? 183

An anonymous reader writes "My colleague at IEEE Spectrum, Eliza Strickland, looked at the home transcranial direct current stimulation (tDCS) movement. People looking to boost creativity, or cure depression, are attaching electrodes to their heads using either DIT equipment or rigs from vendors like Foc.us. Advocates believe experimenting with the tech is safe, but a neuroscientist worries about removing the tech from lab safeguards..."

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