brook

brook's Comments

Coronavirus Virology: A Beginner’s Guide

This is true, and a mistake on my part (they don't bother with IFR in medical school, likely because it's not as relevant for day-to-day medicine as CFR). I'll update the post to try to explain the difference. Thanks a lot.

Coronavirus Virology: A Beginner’s Guide

To your first point: my intuition is that ACE2 is far too small for the genome to pass through itself. ACE2 is an enzyme that's bound to the membrane-- it actually just cleaves angiotensin 1 to angiotensin 2 (hence 'angiotensin cleavage enzyme, ACE2). It does pass through the membrane, but it's not really a 'channel'-- it is simply localised to the cell membrane, and acts on substances extracellularly.

Enveloped viruses can enter cells in many ways (principles of virology chapter 5 is really excellent for this, if you're interested). It seems that SARS-CoV (the original outbreak) enters cells primarily how it is implied above-- simple, direct membrane fusion mediated by the ACE2 receptor. There is some speculation that it may under some circumstances be endocytosed (taken into the cell in a separate sphere of membrane) and then break free of the endosome (the bubble) in a pH-dependent way. Obviously this is further complicated by the fact that this is SARS-CoV-2 that we're really interested in, so I thought it would be best to leave it blank. You're right in thinking this process is similar to SER budding, though.

To your second point: I wasn't actually sure! I've done some research, but honestly I'm still not as confident about this as about the rest. As far as I can tell, for most viruses nucleocapsid shedding is either mediated by substances or organelles inside the cytoplasm-- ribosomes in particular, apparently, bind to the capsids of some viruses and destabilise them -- or is part of the process of receptor binding. Some viruses, for instance, seem to be able to leave their nucleocapsid behind with their envelope so it coats one side of the cell membrane.

Sorry I can't give a better answer, hope it helps!

LessWrong Coronavirus Agenda

What sources are governments using for decision-making?


The biggest impacts seem to me to be via influencing government. The UK government, for instance, is still very reticent to enforce widespread testing or mandatory quarantine. Their 'quarantine guidance' for households with symptoms looks like this, which seems patently foolish for a number of reasons.

Influencing governments' decision making is high-impact and potentially tractable via getting modelling and trial data to them. The UK Government publish their 'scientific basis for decision making' but it appears to be weeks out of date and unreferenced.

With that in mind, how do we get better decision-making information into government? What theory of change can we find for influencing policy makers? I believe this should be primarily targeted towards larger organisations and researchers who can have more direct influence, but may be useful for individuals as well.

How did the Coronavirus Justified Practical Advice Thread Change Your Behavior, if at All?

Primarily or exclusively due to the thread:

  • Bought a pulse oximeter
  • Copper tape on phone, laptop hand-rests, and doorknobs and light switches (due to living in shared student accommodation) -- including recommending others do the same; two or three people I know have taken me up on this advice.
  • Bought, and take daily, vitamin D pills
  • More careful with packages (treat external packaging as if it is infective)
  • Gathered enough food/medicine to be able to quarantine and look after self if required

Due to 'seeing the smoke' due mainly to LW posts (would likely have done otherwise, but much later)

  • Came home to my parents to lower risk from being in a city
  • Properly educated myself on the virus and the outbreak
  • Self-quarantined, including minimising contact from my parents until 15 days asymptomatic living here
Coronavirus Justified Practical Advice Summary

I'd like to suggest not using ibuprofen, or any other anti-inflammatory (NSAID or steroid: also includes aspirin, cortisone, etc. with the presumed exception of pre-prescribed steroids for e.g. asthma).

This is on the basis of this article from the BMJ. In summary, there are a handful of COVID-19 specific cases of young fit people becoming severely ill following ibuprofen use, combined with small studies on SARS-CoV and other illnesses.

Paracetamol should probably be used instead of ibuprofen/NSAIDs.

This seems like a cheap switch as they're likely roughly equivalent in symptom control excepting this effect. Please let me know if you see or read any reason this may be dangerous/untrue. (Is this an appropriate place to post this? Or does it belong in the generalised advice thread?)

Dissolving the Question

This feels to me like part of the puzzle, as you say.

I think the other part is some quality of mind-like-ness (or optimising-agent-ness, if you prefer). People rarely attribute free will to leaves in the wind, despite their inability to accurately model their movements. On the other hand, many people do regularly attribute something suspiciously free-will-like to evolution(s).

I don't have a good idea how either of these two concepts should be represented, or attached to one another, though.

The Second Law of Thermodynamics, and Engines of Cognition

Does this mean, then, that it is not merely difficult, but mathematically impossible for any matter to ever reach 0 Kelvin? This would seem to violate Liouville's Theorem as stated here.

How An Algorithm Feels From Inside

On one notable occasion I had a similar discussion about sound with somebody and it turned out that she didn't simply have a different definition to me-- she was, (somewhat curiously) a solipsist, and genuinely believed that there wasn't anything if there wasn't somebody there to hear it-- no experience, no soundwaves, no anything.