Daily Archives: November 13, 2009

Bring Out Your Dead

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Industrial robot hones virtual autopsies

The researchers are already pioneers of virtual autopsies, or “virtopsies”, which use non-invasive imaging of a body inside and out rather than the radical post-mortem surgery typically used to determine cause of death.

Now they are using a robot, dubbed Virtobot, to carry out parts of that process, making it more reliable – and standardised.

Their virtopsies combine 3D imaging of a body’s surface with a CT scan of its interior anatomy. The result is a faithful, high-resolution virtual double of the corpse (see diagram). This double can be used to accurately determine what killed someone. And it’s a more tactful approach: only needle biopsies are used to sample tissues, leaving a body essentially undamaged.

“Currently, organs are taken out and sliced for analysis of tumours and lesions, but if something is overlooked you have no chance of seeing it again,” says team member Lars Ebert. “All you have afterwards is a huge pile of organ slices.”

Mmmmm. Organ slices …

Weird Science

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I just ran across The 10 weirdest physics facts, from relativity to quantum physics, and as I just finished up an antiscience piece, I thought I’d just turn this into a little Friday rant-o-thon.

Zapperz also ran across this, and rightly notes that nitpicking the details probably won’t matter to non-physicists, because they aren’t likely to pick up on such subtleties. But hey, this is the blogohedron. When nitpicking is out, ranting is in.

The thing you lose with stories like these is that there so much more you could get from them, but the author is admittedly a nonscientist and is missing out on a lot of the neat stuff that live in the details. He’s content to point out some things that are odd, especially when viewed through the prism of the limited everyday-classical-physics experience. The real problem in this is perpetuating misunderstandings of physics. Zz points out a big one — sustaining the concept of relativistic mass. There’s also the insistence that observing can change the past, and one of the new standards, entanglement. Thank goodness teleportation wasn’t mentioned.

Avoiding the Bad Stuff

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Saw this link on Kottke, described as “How to avoid an untimely death,” with the teaser quote

10. If anyone tries to force you into your car or car trunk at gun point, don’t cooperate. Fight and scream all you can even if you risk getting shot in the parking lot. If you get in the car, you will most likely die (or worse).

That sounds like the kind of esoteric crap I like reading, so I clicked on the link to the “Dirty Dozen for Black Swan Avoidance” and boy, was I disappointed. I was expecting a list of some unusual events (some kind of event much more common in a TV or movie plot), with tips for increasing your survival probability, along with a physical or statistical justification. I can easily believe that in the unlikely even that someone is forced into a trunk at gunpoint, that their survival probability is low, and that fighting back is the best option. But there’s nothing cited to back that up.

And the rest of the list is worse. On why you should drive the biggest car you can afford:

Despite all the data from the government on crash test safety, I can say unequivocally that in a 2-car accident, the person in the larger car always fairs better. Force=Mass x Acceleration. The vehicle with larger mass imparts the greater force.

So the claim here is that the NTSB data are wrong? Or to be flat-out ignored? (deja vu) And the physics certainly is. The author seems to have failed physics 101 or forgotten Newton’s Third Law — the forces in a two-body collision are precisely the same magnitude; the reason the person in the lighter car is more at risk in a collision is that they will experience a greater acceleration during that collision. But the author has implicitly assumed that there is only risk from a particular kind of collision, and that there are no mitigating advantages to a smaller car. Cherry-picking your scenario is not science. The same kind of logical fallacy lies behind some people’s justification for not using seatbelts (though the author, thankfully, does not advocate this) — that there are scenarios in which not being restrained will help you survive, but this fails to acknowledge that these are a small minority of all accidents, and that the odds are much greater that wearing a seatbelt will help you, should you be in an accident.

Declaring that you don’t believe in global warming isn’t going to score any science points, and this is kind of scary:

If your gas grill won’t start….walk away. Never throw gas (or other accelerant) on a fire.

Ummm, gas grills use propane, so I hope the two sentences aren’t related, as they appear to be (to me). I heartily endorse not putting gasoline on any kind of fire, but is there some epidemic of people putting gasoline on propane grills? If your propane grill doesn’t start, leave some time for the gas to disperse; propane is heavier-than-air and will “pool up” in the grill and/or area below it, and you’ll get a nice fireball when it finally ignites.

Much of the rest of the list is either obvious or based on anecdotal data, without much justification, even if the advice might end up being sound. But without analysis, there’s no way to tell if dying from the stress of building your retirement home is greater than the risk of dropping dead from shoveling snow.