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Parachute use to prevent death, trauma when jumping from aircraft (2018) [pdf]

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Re: Parachute use to prevent death, trauma when jumping from aircraft (2018) [pdf]

#71

I came to leave a snarky joke comment about "in mice?", and then I remembered that mice don't actually need parachutes because their terminal velocity is roughly the same as a human using a parachute [1]. If someone actually ran the study with mice, they'd find that parachutes aren't necessary! 1: https://johnmjennings.com/can-a-mouse-survive-a-fall-from-a-...

But what's the terminal velocity of a parachute backpack strapped to a mouse?

Round or rectangular parachute?

Re: Parachute use to prevent death, trauma when jumping from aircraft (2018) [pdf]

#72

Earlier quoted context omitted.

The fact that mice don't appear to deliberately jump off high things as a way to get down tells me that they probably do get hurt... Just because they don't fall super fast doesn't mean they don't get injured because they don't have as much distance to "drop and roll" like a human does.

> The fact that mice don't appear to deliberately jump off high things as a way to get down tells me that they probably do get hurt... They explicitly added the caveat about the soft ground. There'd be very little opportunity for mouses to become comfortable with jumping from high areas as there'd be very few occasions that satisfy the requirement. If the mouse jumped into a cave and can't get out, it'd starve to dea…

*mice

Re: Parachute use to prevent death, trauma when jumping from aircraft (2018) [pdf]

#73

> Only two options exist. The first is that we accept that, under exceptional circumstances, common sense might be applied when considering the potential risks and benefits of interventions. The second is that we continue our quest for the holy grail of exclusively evidence based interventions and preclude parachute use outside the context of a properly conducted trial. Both options may be true for different cases. I…

Both options may be true for different cases.

That's option one. Or do you insist on some particular definition of exceptional circumstances?

Re: Parachute use to prevent death, trauma when jumping from aircraft (2018) [pdf]

#74
post #60

Honest question: is this satire or gpt?

It is clear that it is satire, but it does not really work because it asks the wrong question. When you ask the right question (about travelling in an airplane, not jumping out of one) the fact that commercial aviation is conducted without parachutes (though with seat restraints) makes sense.

Re: Parachute use to prevent death, trauma when jumping from aircraft (2018) [pdf]

#76

Earlier quoted context omitted.

The fact that mice don't appear to deliberately jump off high things as a way to get down tells me that they probably do get hurt... Just because they don't fall super fast doesn't mean they don't get injured because they don't have as much distance to "drop and roll" like a human does.

> The fact that mice don't appear to deliberately jump off high things as a way to get down tells me that they probably do get hurt... They explicitly added the caveat about the soft ground. There'd be very little opportunity for mouses to become comfortable with jumping from high areas as there'd be very few occasions that satisfy the requirement. If the mouse jumped into a cave and can't get out, it'd starve to dea…

Mice around me fairly frequently climb trees. They know whats at the bottom of the tree (hard soil). Yet I never see them jumping off - they always climb back down the way they came up.

It could be to avoid getting disorientated though, or to be able to see a predator and reverse course...

Re: Parachute use to prevent death, trauma when jumping from aircraft (2018) [pdf]

#77

Earlier quoted context omitted.

The fact that mice don't appear to deliberately jump off high things as a way to get down tells me that they probably do get hurt... Just because they don't fall super fast doesn't mean they don't get injured because they don't have as much distance to "drop and roll" like a human does.

>The fact that mice don't appear to deliberately jump off high things as a way to get down tells me that they probably do get hurt... Isn't this how bats have evolved though?

Not directly. There was one or more intermediary stage, probably jumping between trees. Outside my window, the squirrels are busy doing just that.

I have a vague recollection of reading that most squirrels have evidence of trauma from falling, such as healed bone fractures.

Re: Parachute use to prevent death, trauma when jumping from aircraft (2018) [pdf]

#79

How do we really know whether double blind randomized controlled trials actually work? Is there any RCT done on evaluating the efficacy of RCT?

A good post on the subject: https://slatestarcodex.com/2014/04/28/the-control-group-is-o...

Re: Parachute use to prevent death, trauma when jumping from aircraft (2018) [pdf]

#80

I came to leave a snarky joke comment about "in mice?", and then I remembered that mice don't actually need parachutes because their terminal velocity is roughly the same as a human using a parachute [1]. If someone actually ran the study with mice, they'd find that parachutes aren't necessary! 1: https://johnmjennings.com/can-a-mouse-survive-a-fall-from-a-...

Not in mice, but in stationary aircraft sitting on the tarmac - so even less useful than a study using mice.
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