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Comment Re:Junk Science (Score 5, Informative) 146

There are a number of things to unpack here.
To a statistician, "significant" means "very unlikely to have happened purely by chance", i.e. we are seeing a real difference, not sampling error. To a lay person, "significant" means "big enough to matter". You are arguing that this result is not significant in the second sense.

If there are non-linearities in a system, small shifts in the mean can have a large effect. For example, a town has natural temperature range between -20C and +45C. An increase in the mean of 2C is small compared to that range. However, the number of days per year hotter than 40C might easily triple with that +2C shift in the mean (due to the shape of the high temperature tail of the distribution), and if >40C is a threshold for causing major health problems, then the small shift has a large effect.

145g might be significant in this way: a 1355g baby might have much worse survival chance than a 1500g baby. (Further complicating things, although the mean might shift by 145g, the shape of the distribution might also change. The shift could affect low weight babies more or less strongly than normal weight babies.) I don't know enough about babies to know whether that 145g shift is important or not.

Comment Re:Limit of Energy Density (Score 1) 145

Electric cars lose on the energy storage, but win on the engine. Instead of 300 kg of engine and 70 kg of fuel in a petrol car, you can have 30 kg of motor and 340 kg of battery in an electric car without increasing the mass. (Note that those masses are guesswork on my part.)

On top of that, it is hard to sell cars with 100 mile range, so electric cars dedicate more of their mass to propulsion+energy storage than fossil fuel cars.

Comment Re:What's in the future for batteries? (Score 2) 145

There are many reasons why this isn't ever happening. A very big one is that such a 'battery' would be producing heat all the time. Say your device has 10W peak demand, and your radioisotope thermal generator (nuclear battery) has efficiency 10% (better than we've yet achieved), then you'd need an RTG which was emitting 100W of heat all the time. (On the plus side, it would do a fine job of heating the interior of your car on cold days.) (If your device only uses 10W occasionally, you could pair a 1W output RTG with rechargable batteries, but now all you're saving yourself is the need to plug it in each night.)

Further reasons:
* Cost - even with efficiency of scale, producing radio isotopes will be very expensive
* Scaling - the technology works (sort of) for 100W power generation, it may be hard to scale down to 10W or 1W
* SIze - a 100W RTG is the size of a person.
* Safety - they contain really nasty radioactive sources. If you use alpha emitters, you can make them 'safe' with very thin shielding, but once the material escapes into the environment (e.g. in a house fire, or someone chops the battery with an axe) it is very nasty indeed.

Yes, future technology can help somewhat with any of these - but it needs to improve all of these problems, each by many orders of magnitude, before nuclear batteries will be practical.

Comment Re:Just looking at the first few questions... (Score 2) 145

The five stages of name-pun reaction:
1) Amusement. This stage starts at age about 4 to 6, when the punee first gets the joke. It typically lasts about 30 minutes.
2) Tedium. This stage typically lasts a few months
3) Anger. Will you stop with that stupid joke already?
4) Bargaining. If you stop making those stupid jokes, I'll stop pummelling your ribs with a baseball bat.
5) Acceptance. Let the jokes flow through you, omnipresent yet harmless like the air. Find your inner peace. Make it your life's mission that everyone who has ever made this joke will be carrying in their pocket a chemical bomb of your design.

Comment Will there always be a demand for lithium? (Score 1) 145

Demand for lithium is soaring and supply is scrabbling to keep up. If I was contemplating constructing a lithium mine/extraction facility, I would be worried that my investment might do fine for five years and then suddenly become worthless when some new battery chemistry came along. Is this fear justifiable? Is it reducing current or near-future lithium supply?

Submission + - Supermassive black hole rocketing out of distant galaxy at 5 million mph

The Bad Astronomer writes: Astronomers have found a supermassive black hole barreling out of its home galaxy at 5 million mph. The 3 billion solar mass behemoth formed from the merger of two slightly smaller black holes after two galaxies collided and themselves merged. The resulting blast of gravitational waves is thought to have been asymmetric, causing a rocket effect which launched the resulting black hole away. It's currently 40,000 light years from the galaxy's core.

Comment Re:Why federal law? (Score 0) 174

I am not now and never have been a citizen of the USA, so chalk me up to non-purposely ignorant.
Reading TFA more closely, this proposed law would only apply to federally funded highways: "the dig once bill requires states to evaluate the need for broadband conduit any time they complete a highway construction project that gets federal funding."
And local bodies are in on this too: "Dig once doesn't have to be just for state and federal projects, as cities such as Boston and San Francisco already require it locally."

Comment Re: well, botox is accepted (Score 1) 41

I've considered that - it would take some care not to accidentally die of wrong pH blood or bad electrolite balance or somesuch. I'd also need to find the toxic dose when injected - hopefully way less, because I don't think injecting a kg is doable.
I think of this goal as protection against suicide. If I am ever suicidally depressed, it will look like just too much effort to die by vitamin C overdose, so instead I'll live.

Comment Re:well, botox is accepted (Score 1) 41

The drug is found in venom, but is not itself venomous. (Source: listening to radio interviews.)
In addition, any drug is toxic in sufficient dose. (Some drugs are toxic at their therapeutic dose, such as chemotherapy. Use of such drugs requires a careful cost-benefit analysis.)
I've decided that should I ever decide to commit suicide, I'm going to try to be the first person ever to die of vitamin C toxicity. It will take about a kilogram.

Comment Years off (Score 1) 41

These results are from experiments on rats. In radio interviews, the researchers said that human (phase I) trials were at least 18 months away. I'm no expert on how long clinical trials take, but I'd expect phase I through phase III couldn't be under three years, so expect 5 + years until this is in your ambulance's medicine cabinet.
Try not to have a stroke before then.

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