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Old Spleens Suck (2021)

sarahconstantin.substack.com

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Re: Old Spleens Suck (2021)

#61

Post by londons_explore »

TylerE wrote: post #56
Hallucinaut wrote: post #54

Earlier quoted context omitted.

Obviously if you're ejecting at or near supersonic speeds there are other stresses, but if the trauma is mainly from the ejection booster itself why is it still done with such force? It seems like a majority of ejections shouldn't be benefited by half a second less time to achieve clearance (or the jet itself could detect altitude and adjust the speed to increase survivability). I'm guessing this is also a function o…

Because you have to get up and over the tail of the airplane without it slicing you like a cleaver.

A cleverer ejection seat could track the tail and body of the craft, and adjust the rocket force based on the trajectories in each case.

Then you don't have to use enough force to avoid the tail in every case, but merely enough force to avoid the tail in this case, which will normally be far less.

Re: Old Spleens Suck (2021)

#62

Post by gscott »

mescaline wrote: post #47
gcanyon wrote: post #42

I've been without a spleen for longer than I had one. I wonder if -- if any of this translates to humans -- spleens are beneficial to the young but a risk to the old, meaning that since I survived my youth without, it's all good going forward; or if young spleens give long-lasting benefits, meaning that the best course is to have the spleen into old age, but then jettison it later in life (than I did).

Did you get vaccines to compensate? I've been told there are three that I need, but not sure when or if I need boosters.

pneumovax every 5 years

Re: Old Spleens Suck (2021)

#63

Post by gscott »

ryeights wrote: post #10

I think it is obvious at this point that the human body is designed to self-destruct, causing death at old age, once a certain biological threshold is reached. Resistance to this idea comes not from a rational perspective, but a semi-religious belief that your own body would not betray you.

I plan to go to China every 15 years and get all new organs. As long as I don't accidentally turn on Tesla Auto-Pilot I should live a long time.

Re: Old Spleens Suck (2021)

#64

Post by flobosg »

pavlov wrote: post #2

I honestly expected this article to be about the other meaning of spleen, a melancholy or depressive longing (as in Baudelaire’s “Le spleen de Paris”). Something about looking forward, giving up old spleens, etc. Instead it’s genuinely interesting information about how an organ changes over time.

> the other meaning of spleen

TIL; and of course it is derived from Hippocrates’ theory of humors…it all makes sense in retrospect!

Re: Old Spleens Suck (2021)

#65

Post by threatripper »

ryeights wrote: post #10

I think it is obvious at this point that the human body is designed to self-destruct, causing death at old age, once a certain biological threshold is reached. Resistance to this idea comes not from a rational perspective, but a semi-religious belief that your own body would not betray you.

> body is designed to self-destruct

This way of thinking is dangerous. This is like saying that there is "planned obsolescence" when in reality products are designed to last a certain period. They are not designed to fail after that period but they are also not designed to last longer than that period. The end result is similar but the intention is totally different.

Re: Old Spleens Suck (2021)

#66

Post by TylerE »

londons_explore wrote: post #61
TylerE wrote: post #56

Earlier quoted context omitted.

Because you have to get up and over the tail of the airplane without it slicing you like a cleaver.

A cleverer ejection seat could track the tail and body of the craft, and adjust the rocket force based on the trajectories in each case. Then you don't have to use enough force to avoid the tail in every case, but merely enough force to avoid the tail in this case, which will normally be far less.

Solid fuel rocket, so no throttle.

Re: Old Spleens Suck (2021)

#67

Post by inglor_cz »

krisoft wrote: post #4
gonehome wrote: post #3

There’s another interesting spleen fact that I remember reading: people who survive flight ejections and hitting water at high speed tend to have had their spleens removed. Probably because otherwise the impact causes a rupture and you bleed out too quickly to survive.

What do you mean by “flight ejections”? Are we talking about ejection seat activations in military aircraft? This factoid sounds very suspect. Doesn’t most people who need to activate an ejection seat survive spleen or no spleen? Deaths may occur of course, an ejection is not without risks, but if everyone or nearly everyone with a spleen dies then my understanding of the risk associated with an ejection is seriously…

An ejection seat is basically a rather powerful small rocket with huge acceleration - much more forceful than what astronauts nowadays experience. Human bodies aren't built for riding such rockets. Injuries from ejections are pretty common and some of the ejectees are never fit to be combat pilots again.

Re: Old Spleens Suck (2021)

#68

Post by dm319 »

The premise of this article is based on a single study in 1969 on mice. I agree with the general premise that the immune system ages and becomes less effective as we get older, but will need more convincing that removing the spleen will make you live longer.

Re: Old Spleens Suck (2021)

#69

Post by _Microft »

rhn_mk1 wrote: post #59
pacaro wrote: post #19

IIRC a lot of our data about human splenectomy comes from World War II, where it was performed often enough that some long term followups were possible with sufficiently large n

umbers.

That was more than likely not a typo. n is used like this in some fields:

https://en.wikipedia.org/wiki/N#Other_uses

Re: Old Spleens Suck (2021)

#70

Post by jstanley »

ryeights wrote: post #26
cheschire wrote: post #18

Earlier quoted context omitted.

Why is that “obvious” and why is the “other” side the religious one and not your “design” assertion? I’m not an expert on such subjects but it seems more closely related to the concepts of evolution to say natural selection does not show preference for abnormally long lived individuals because it is unknown or unimportant at time of procreation which traits lead towards lifetime longevity beyond short term hunter gat…

Under the traditional view, the most evolutionarily advantageous individual is one that lives forever and continues to spread their genes indefinitely, producing hundreds of offspring. Why is this not what we see in practice?

There's no advantage to having a single individual who lives and reproduces forever compared to having his offspring, and his offspring's offspring, etc. reproduce forever.
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