A critical question as regards the new coronavirus has been to what extent it is transmitted by asymptomatic people. But really there isn’t just one definition of “asymptomatic”. Instead, there are several possible definitions, each of which is useful in a different way:

Since hearing that there’d been 47 protesters killed in one day on the Maidan in Ukraine, shortly before President Yanukovych was forced from office, I’d idly wondered how it happened. Then, a couple of years ago (this blog is seldom timely), I ran across the video compiled by Evelina Nefertari which takes video clips taken by wide variety of people on that day and combines them into a single time-synchronized video stream showing many clips simultaneously.

The killings are commonly described as a massacre, but watching the video (and viewing maps and summaries of the action), a very different phrase seems much more apt: an infantry assault – and not an assault on the protesters; an assault by the protesters.

The phrase “history is written by the winners” is commonly uttered these days, which goes to show how many people repeat things without thinking about them, since a moment’s thought would reveal that it is incorrect. Plenty of history has been written by losers, for any and every meaning of the word “loser”. Many histories of the Civil War were written by the defeated Confederates, and the influence of those histories continues even today. Defeated Germans likewise wrote memoirs of their World War II experiences – memoirs which have not always been believed by the victors, but which in some respects have been and deserve to be.

There are people who look down on puns, and scold others for making puns, saying that they’re not funny.

I’ve been reading about oxygen therapy, and at first was a bit surprised how inefficient it is. The actual human use of oxygen at rest (the amount that gets used as an oxidizer and ends up as CO2 or water) is about 0.25 liters per minute, yet oxygen concentrators meant to adequately supply a single person normally put out about 5 liters per minute. And although the oxygen concentration coming out of the machine is 90% or so, inefficiencies in the way it is actually delivered to the mouth and nose reduce that to where patients are usually breathing a concentration of less than 50% oxygen (as compared to the normal 20% oxygen concentration of the atmosphere).

People are making fun of President Trump for insistently thinking that a vaccine for the new coronavirus can be put out quickly, but as entertaining as it can be to make fun of politicians who are out of their depth in a highly technical area, the man has a point. A more constructive conversation might have gone like this:

I’ve been puzzled for a while as to why fentanyl has been killing so many people. Okay, gram for gram it’s much more potent than other opiates – something like a hundredfold. But drug dealers know this and dilute it accordingly. Junkies can be quite careless with their lives, but usually don’t try to kill themselves intentionally. So what explains the tens of thousands of deaths?

As a young student, I liked the idea of patents. Here, it seemed, was a system to properly reward the sort of person I was planning to become. But gradually I came to notice that everybody I admired for their scientific and engineering achievements took a rather dim view of patents. Being practical people, they sometimes took out patents (there was money in it), but without any feeling that the patent system was really the right way of rewarding them; on the contrary, they often pointed out absurdities in it. Richard Feynman, for instance, was the “inventor” listed on the patents of the nuclear airplane, the nuclear reactor, and the nuclear rocket, and treated the whole thing as a joke.

In an article which was mostly about another topic, I ran across this:

When they teach soldering, they say that you should heat the work, not the solder. This is true, but what’s also true is that to heat the work with a soldering iron, it helps a lot to have a bit of solder between the two: the heat conductivity of solder is much greater than that of air, and the small contact patch that a dry soldering iron makes with the work is miserable at transferring heat.