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"These studies in python behaviour were possible after these snakes ate the radiocollared possums we were radiotracking "

"We scaled the cryogenic pods around barbie dolls because the boss wanted one for his desk. "

"N was reduced to save my marriage. "

"the eppendorf tubes were "shaken like a polaroid picture" until that part of the song ended"

And so many more.
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Went up to Gisborne yesterday with Rey and friends to play with rockets. A good time was had by all!

One of our friends' rockets had an on-board video camera, which captured this footage of one of the more entertaining flights. The jolt at 00:14 is when the ejection charge blows off the nose-cone, releasing the parachute intended to bring the rocket safely to earth.

Rey had a couple of flights with her birthday rocket, and then let me prep it for the third launch. It went VOOM up into the sky, nose-cone blew off as designed, but parachute failed to emerge. The body came hurtling back down and hit the ground hard; I was expecting to find I'd broken Rey's birthday present, but somehow it had managed to come straight down into soft earth, hitting on its strongest axis, and bury itself three inches in the ground without sustaining any damage. Hooray for cardboard and plastic!

All in all, a great afternoon out. Now back to the maths marking.
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Humon, of 'Scandinavia and the World', has been doing an adorable series on the love lives of animals. (Link NSFW)

And by 'adorable' I mean "Fred Phelps probably would not approve".
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I am ambivalent on nuclear power. In theory, I think it could be a good thing if properly handled. I don't have a knee-jerk anti-nuclear reflex, and quite willing to acknowledge that all energy solutions have their failings, whether they involve pollution or scale.

And I'm not impressed by the quality of a lot of the nuclear debate. A lot of people are willing to decry nuclear power simply because the worst-case scenario is very very bad, without attempting to look at the whole of the risk/benefit tradeoff: nuclear has a risk of killing a lot of people and rendering countryside uninhabitable in a spectacular fashion, whereas coal kills a small number of people every day in an unexciting sort of way that doesn't sell newspapers. (And via climate change, has the potential to kill a large number of people in an indirect, deniable sort of way.)

So in theory, my view is that if nuclear works out better than coal when all possible scenarios are taken into account (weighted by their probability), we should replace coal with nuclear. That's the theory.

The problem is... well, let's look at that disaster that happened in 1986.

No, not Chernobyl, the other one. )
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I am generally refraining from comment on the Japanese situation, because I don't have much useful to say, and the media is full enough already of newspaper articles about retweets of amateur analysis of sensationalistic news reports based on the utterances of people who don't know exactly what's happening and might not want to tell the truth if they did. But a couple of things.

Thing 1: There are some engineering PhDs (well, at least one) declaring that "the plant is safe now and will stay safe".

As another engineering PhD, I would be extremely reluctant to make such confident assurances outside my field of expertise, and I think the guy cited above - who is mech eng, NOT nuclear - is unwise to do so. (In fairness, I'll also note that he doesn't appear to have intended his post for widespread distribution, or perhaps he'd have been more circumspect.

Honestly, even if he WAS a nuclear engineer, I'd have reservations. Nuclear power plants are built to tremendously high engineering standards, but they're complex systems and Sod's Law is a powerful thing.

Thing 2: Since none of us know what's going on inside the reactors at the moment, we're all talking about the one thing we can quantify: radiation measurements. That's well and good, but if you're doing so, please make sure you're using the units correctly.

The sievert (Sv) is a measurement of how much harmful radiation a person has received*. If you catch about 1 sievert or more in a short period, you're probably in trouble. A millisievert (mSv) is one-thousandth of a sievert, and a microsievert is one-millionth of a sievert.

Sieverts per hour (minute, second, year) is a measure of how fast that exposure is accumulating. If the radiation level is 100mSv/hr and you stay there for an hour, you're going to pick up 0.1Sv. If it's 400mSv/hr and you stay there for 15 minutes, you're also going to pick up 0.1Sv.

What this means is that if a radiation level is just reported in "sieverts", with no "per $TIME_UNIT" attached, you're missing information. It is quite likely that it's meant to be "per hour", but who knows?

Think of it like this:

Arnold: I make $5000 a week.

Barbara [writes newspaper article]: Arnold makes $5000.

Carla: I make $25,000 a year.

David [writes newspaper article]: Carla makes $25,000.

Edgar [reads both newspaper articles]: Hey, Carla makes five times as much as Arnold!

If your sources don't understand the distinction between total exposure and rate of exposure, they're probably not useful sources, and trying to draw conclusions from them is a bad idea.

*There are many other radiation-related units out there - rads, curies, becquerels, grays, rems, etc etc, with different meanings and purposes. Wikipedia should have a good discussion if you're curious.
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Article in the Economist about the 'Clever Hans' effect in sniffer dogs:

When handlers could see a red piece of paper, allegedly marking a location of interest, they were much more likely to say that their dogs signalled an alert. Indeed, in the two rooms where red paper was present and sausages were not, 32 of a possible 36 alerts were raised. In the two where both red paper and sausages were present that figure was 30–not significantly different. In contrast, in search areas where a sausage was hidden but no red piece of paper was there for handlers to see, it was only 17.

The dogs, in other words, were distracted only about half the time by the stimulus aimed at them. The human handlers were not only distracted on almost every occasion by the stimulus aimed at them, but also transmitted that distraction to their animals–who responded accordingly.

Also, this video is rather nifty. I'm not a huge fan of Manson (he has some OK songs, the shock-your-parents marketing gets a little wearying) but this guy has really made an effort. (Audio NSFW, but you can watch with the sound turned off.)

(Embedding seems to be misbehaving, so replaced the embed with a link.)
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Brian Deer's BMJ article on Wakefield's anti-MMR work is available here. It's interesting reading; Deer reports that none of the twelve cases in Wakefield's paper were accurately described. In particular, he reports that timelines were altered; kids who showed initial symptoms of autism six months after MMR vaccination, or a week before, were all represented as showing their first symptoms shortly after the vaccination.

Out of curiosity, does anybody have a feel for how much profit Big Pharma makes out of providing childhood inoculations... as opposed to the profits they would make providing lifetime care to kids suffering permanent after-effects from mumps/measles/rubella complications? I suspect the latter is substantially greater than the former but that's just my guess.


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February 2017



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