November is here, and that means a massive shift is coming. And by "massive" I am of course referring to the redefinition of the kilogram unit of mass that the world has been building up to for more than 100 years. Let me explain:

Kilogram, kg (mass)
Meter, m (distance)
Second, s (time)
Kelvin, K (temp)
Ampere, A (electric current)
Candela, cd (luminous intensity)
Mole, mol (quantity)


Image credit: "The State of the Unit"


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Hard agree. And if this is useful, let me share something that often gets omitted (not by @kakape).
Variants always emerge, & are not good or bad, but expected. The challenge is figuring out which variants are bad, and that can't be done with sequence alone.
You can't just look at a sequence and say, "Aha! A mutation in spike. This must be more transmissible or can evade antibody neutralization." Sure, we can use computational models to try and predict the functional consequence of a given mutation, but models are often wrong.
The virus acquires mutations randomly every time it replicates. Many mutations don't change the virus at all. Others may change it in a way that have no consequences for human transmission or disease. But you can't tell just looking at sequence alone.
In order to determine the functional impact of a mutation, you need to actually do experiments. You can look at some effects in cell culture, but to address questions relating to transmission or disease, you have to use animal models.
The reason people were concerned initially about B.1.1.7 is because of epidemiological evidence showing that it rapidly became dominant in one area. More rapidly that could be explained unless it had some kind of advantage that allowed it to outcompete other circulating variants.
Variants always emerge, & are not good or bad, but expected. The challenge is figuring out which variants are bad, and that can't be done with sequence alone.
Feels like the next thing we're going to need is a ranking system for how concerning "variants of concern\u201d actually are.
— Kai Kupferschmidt (@kakape) January 15, 2021
A lot of constellations of mutations are concerning, but people are lumping together variants with vastly different levels of evidence that we need to worry.
You can't just look at a sequence and say, "Aha! A mutation in spike. This must be more transmissible or can evade antibody neutralization." Sure, we can use computational models to try and predict the functional consequence of a given mutation, but models are often wrong.
The virus acquires mutations randomly every time it replicates. Many mutations don't change the virus at all. Others may change it in a way that have no consequences for human transmission or disease. But you can't tell just looking at sequence alone.
In order to determine the functional impact of a mutation, you need to actually do experiments. You can look at some effects in cell culture, but to address questions relating to transmission or disease, you have to use animal models.
The reason people were concerned initially about B.1.1.7 is because of epidemiological evidence showing that it rapidly became dominant in one area. More rapidly that could be explained unless it had some kind of advantage that allowed it to outcompete other circulating variants.
All modern research questions frame your mindset and self-frame research paradigm. Broad thinking: how little of everything can a citizen survive on; how cheap can your upkeep be? /1
When an American patient lands in an Austrian hospital for a back problem, a doctor tells him to perform a set of exercises.
- How many?
- Do you have anything else to do? /2
This interchange illustrates two mindsets colliding at bedside. How little can I get away with vs there is no limit to effort when it comes to your wellness. /3
When you were robbed of movement, somebody started selling you exercise. To understand that digging a ditch, to build a house, or to carry a child around, or waking to your grandparents for an hour is not the same as jogging on a treadmill... will reveal what research hides.
/4
When I talk about doing a purposeful activity outdoors, I look at complexity of movement, purpose, meaning, sun, and air, even an opportunity to meet a neighbor... that is now reduced to a calcium pill, vitamin D, an antidepressant, an osteoporosis shot, and an oxygen tank. /5
Is moderate exercise enough to live as long as possible, or should you be doing vigorous exercise? And what proportion is best? This article has the answers. https://t.co/YJqpaaI0UR
— Sebastian Rushworth M.D. (@sebrushworth) January 24, 2021
When an American patient lands in an Austrian hospital for a back problem, a doctor tells him to perform a set of exercises.
- How many?
- Do you have anything else to do? /2
This interchange illustrates two mindsets colliding at bedside. How little can I get away with vs there is no limit to effort when it comes to your wellness. /3
When you were robbed of movement, somebody started selling you exercise. To understand that digging a ditch, to build a house, or to carry a child around, or waking to your grandparents for an hour is not the same as jogging on a treadmill... will reveal what research hides.
/4
When I talk about doing a purposeful activity outdoors, I look at complexity of movement, purpose, meaning, sun, and air, even an opportunity to meet a neighbor... that is now reduced to a calcium pill, vitamin D, an antidepressant, an osteoporosis shot, and an oxygen tank. /5