Sorted by New


Lessons I've Learned from Self-Teaching

Very interesting article! A big part of the outlined techniques I also kind of discovered by trial and error.

I recently also started to work more on my math skills and putting in the mathjax was getting very time consuming. To reduce that bottleneck I can recommend this small app: https://mathpix.com

PS: I stumbled once over this collection of proofs without words and they make great Anki cards to build up intuition: https://mathoverflow.net/questions/8846/proofs-without-words

My favorite essays of life advice

A book that goes very much in that direction with small but impactful chapters is:

“Chop Wood Carry Water”


I really enjoyed (and as I’m now reminded of it, I will have a look at it again) and I guess you could like it too.

(I found it via https://fs.blog/reading-2019/ and the very good review got me interested in it.)

Covid 10/22: Europe in Crisis

Out of curiosity I had to look at the FT chart with relative numbers (= seven-day rolling average of new cases (per million), by number of days since 0.1 average daily cases (per million) first recorded):

Linear scale:


Log scale:


It looks like the next weeks will show where the situation will go. The curve for some countries looks quite bumpy on the log scale. 

The Quantitative Reasoning Deficit

I guess a deficit in quantitative reasoning is just one of the contributing factors.

Another contributing part, I keep thinking about a lot, is the role of social media during the pandemic. Social media is making money by engaging people. The longer people are on your platform, the more data you can harvest and the more advertisements you can show them, resulting in more revenues. And the more data you have, the better you can target the ads, and so on. The best way to drive up engagement is to promote controversial posts (the more extreme the better, you like it and share it or you don't like it and talk about it). This leads to filter bubbles. By knowing the main orientation of those filter bubbles it is easy to drive up engagement by showing each filter bubble some posts that are aligned to their views (maybe even increasing to more extreme topics and standpoints).

Of course this is not beneficial for the society as a whole and it drives division and is not improving a culture of open discussion, but it is currently a great and more or less unregulated money making machine.

Pair that with a very capitalistic society without a lot of social security nets and a situation that brings people to the edge (i.e., pandemic) and the outlined mechanics from above is running even faster/better (isolated people, increase of fear of the unknown, mental health issues, etc.).

(And hey, you can even use this technology (unofficially) to harm other parties and cause a lot of damage with a fraction of the cost of traditional operations.)

And in the end, the outlined aspect comes down to misaligned incentives.

(Note: Maybe I was reading recently too much about misinformation using natural language processing.)

Why don't we have active human trials with inactivated SARS-COV-2?

To grow the virus and inactivate them by chemical reagents is the standard setup for (older) influenza vaccine systems that are egg- or cell-culture-based. From such a setup whole-virus- or subunit vaccines can be derived.

What are the costs, benefits, and logistics of opening up new vaccine facilities?
Answer by micpieApr 01, 202021

To produce a vaccine, you will need at least:

  • Vaccine (or at least a rough idea what your vaccine will be going to look like)
  • Large scale production process (which is not the same as a bench scale process)
  • Raw materials
  • Facility (see below)
  • Staff (see below)
  • A working quality system (including an ok from the regulatory agencies)

In biopharmaceutical production you have two kind of extremes in the facility design:

  • "Stainless steel" facility: This is usually the option if you are going to produce the same product forever. It needs a higher upfront investment but comes with lower operating costs. If you take care of such a facility you should be able to use it for a long time. Construction time should be higher than for the option below, but will depend highly on the exact setup.
  • "Single use" facility: This facility design is sometimes referred to as a "ballroom" design because it just comes with the clean room and the needed media (e.g., water, gas, etc.) and uses single-use equipment for the production itself (i.e., plastic bag, tubing, etc.). This setup needs less upfront investments and has higher operating costs (usually due to the expensive single use equipment). There are also production systems which are built into containers.

Of course, everything between those two designs is possible. Both types can be designed to produce multiple products which is referred to as a "multi-product facility". Depending on the automation grade you will need more or less staff with more or less training and experience. For the ramp-up of the facility and for ongoing troubleshooting you will need (highly) educated stuff.

The vaccine production systems can be roughly classified into these variants:

  • Egg-based: Egg gets infected with virus, virus particle or parts of it are used for the vaccine.
  • Cell-culture-based: The same as above, but you infect cells.
  • Microbial/insect-based: Usually used to express subunits of the vaccine and no entire virus particles. Can be also used for DNA vaccines?
  • (Fully?) synthetic: Nucleic acid- (i.e., RNA, DNA) or poly-saccharide-based vaccines?

These outlined systems are quite different, and, therefore, the facilities will look different. However, a well-designed multi-product facility should be able to cover a wide range of the possible vaccine types because basic fluid handling and a lot of other steps are similar.

The most similar historical equivalent I can think of is the penicillin production, although there the circumstance where quite different.

Vaccines are one of the most cost-effective medical preventive measures but usually the margins are thin. This is why the investments in such products has not seen the levels of treatments of civilization diseases, e.g., cancer or diabetes.

Edit: Added large scale process to the points at the beginning.

How will this recession differ from the last two?

No direct prediction from my side but a link to a report: https://www.mckinsey.com/business-functions/risk/our-insights/covid-19-implications-for-business

The full PDF report (linked on the website) has on page 15 a overview of possible outcomes that could be a basis for discussion.

Load More