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Comment Re:Vacuum? (Score 4, Informative) 107

Easy. Masks drop from above you and emergency braking and re-pressurization is started. If braking to a safe velocity (say, 300km/h) is limited to 0.5G then it can be completed in about 40 seconds. Then once everybody have slowed down, emergency vents can open and the tube can be quickly re-pressurized to breathable pressures. You will survive even in the case of immediate complete pressure loss and failure to put on a mask.

Comment Re:Taxis = artificial barriers to competition (Score 1) 204

You get insurance automatically when you drive with a fare. You don't need to spend anything on it.

What you probably _should_ get is an insurance for yourself when you're driving between fares. For AAA it's an additional $20 a _year_. I'm using Metromiles and it's a 5% surcharge on top of the usual premium.

Comment Re:This allows of big modifications (Score 1) 110

No, DNA replication is not energetically expensive for eukaryotic cells. Most of the energy in a cell is spent on protein synthesis (i.e. gene expression), so regulatory mechanisms to suppress or promote DNA transcription are very honed and fine-tuned. These mechanism are also co-opted into fighting DNA parasites but they can't be used to edit away junk DNA completely.

However, for bacterial cells (which are much smaller than eukariotic cells) DNA replication is a significant burden and so they have very little DNA junk. That holds true for intracellular symbiotes like mitochondria and chloroplasts - their genomes are under (some) pressure to get simpler and smaller.

Comment Re:This allows of big modifications (Score 1) 110

Duh. LINEs are basically just promoters with a small payload attached, so a LINE that jumps in front of a protein can work perfectly fine. There are several cases in genome where LINEs actually _replaced_ the regular promoters. Again, it's just a couple of cases out of literally millions. We _expect_ such discoveries.

What we don't expect is that a significant fraction of junk actually has a useful function.

Comment Re:Genetic spare parts? (Score 1) 110

Not a "bunch" but "perhaps tens or hundreds of places out of several million". People really underestimate the amount of junk DNA - it's 95% of the genome, around 3 billions base pairs. In all this junk we sometimes find a few kilobases here and there that actually have some useful functions. Just for reference - all the known regulatory non-coding sequences amount to less than 20 megabases out of that 3 gigabases.

Is it likely that there are more hidden gems out there? Sure. Is it likely that a significant portion of junk DNA is non-junk? Nope.

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