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Comment Re: More ambiguous cruft (Score 1) 514

A lot of GMO efforts are aimed at reducing the use of pesticides, especially ones we know are harmful. Others are to increase yields or allow things to be grown In areas that would otherwise not be suitable.

We may grow lots of food in North America but it's done at a high cost to the environment, and getting it to places where they don't grow lots of food has always been a problem.

Comment Re:This is fine in theory (Score 2) 126

I don't think it's an interferometer. It's a standard diffraction lens, just like the Canon one you linked, that produces a real image, not an interference pattern. You could stand at the focal point and see an image.

It would be an interferometer if you put a ring of telescopes on the rim instead of at the focus.

Comment Re:Bullshit (Score 4, Informative) 211

Action potentials are a bit funny. They're not actually movements of electrons down a wire like we're used to thinking about, but rather propagating waves of changes in the way cellular pumps move heavy ions through the cell membrane. Action potentials provide essentially no long-distance current, for example.

If you applied 15 mV across the SA node (the heart's built in pacemaker) at just the right time in the cardiac sequence you might be able to interfere enough to stop the organized contraction. There's a lab at my university that's been looking at analyzing chaotic heart contractions in order to use very small, very well-timed pacemaker signals, to correct them.

You would absolutely have to do it internally though ("applied directly to the heart"). The human body is basically a bag of salt water, which conducts quite well (about 300 Ohm from head to toe IIRC) surrounded by skin, which is a pretty good insulator. So if you want to electrocute someone, stab the electrodes in first.

Comment Re:Hold your horses (Score 1) 211

You missed his point. 1 nA per ring, second, hour, whatever, makes no sense. An amp is already of measurement of charge per unit time. If the current measurement is correct, which I believe it is, then the GP's formula is correct. Multiplying a current (charge / unit time) by a time gives you a measure of total charge. Multiplying by the voltage then gives you total energy.

Comment Re:Interstellar missions... (Score 2) 211

The previous posters are correct - the clear, low humidity air over deserts is more transparent to infrared light and radiative loss is the major reason for fast cooling at night. I've spent the night out in the Sahara. When the air cools off and you dig into the sand you realize that not only is the sand a decent insulator, just below the surface it's also much warmer than the air.

Comment Re:Interstellar missions... (Score 1) 211

Dry batteries don't work well in the cold because chemical reactions slow down the colder it gets. Wet batteries don't *survive* the cold because things freeze. I say this both as someone whose camera batteries often needed to be hand warmed, and as someone who's had to change a car battery at -40 because it discharged, froze and cracked it's case.

Comment Re:Bullshit (Score 1) 211

You probably could stop someone's heart with 15 mV. But it would have to be applied directly to the heart, and at just the right time.

For external application (i.e. without the open heart surgery) it's going to take rather more than that. You generally need a current of around 100 mA through the heart to stop it. If you're not standing in a puddle of salt water or gripping a water pipe, it's going to take quite a bit more voltage to achieve that.

110 V household current can kill, if you manage to get a good connection hand to hand. I think the lowest voltages observed to kill someone were around 40 V, but that requires some fairly exceptional circumstances.

Comment Re:The "what?!" is reaction time (Score 1) 304

Crashes have been getting much more survivable, but the number of collisions per car-kilometre has also been flat or dropping. Texting in North America took off in a fairly short period of time. If it were actually responsible for as many crashes as it gets blamed for there would have been a big spike in the collision rate. There wasn't. That supports the idea that the ultimate cause is bad drivers, and texting is just the latest thing they can be distracted by. Texting while driving is undoubtedly dangerous, but so are a lot of other things people do in cars.

Comment Re:Extradition? (Score 1) 299

I imagine the laws governing cars are much like those for boats, but less enforced for individuals. If you're the skipper of a boat you can share costs with guests/crew/passengers but those costs cannot be more than the consumables used on the trip and they cannot pay you for your time. As soon as you accept payment for your services you need commercial permits, your boat has to meet more stringent standards, etc.

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