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Why does your coronavirus micrograph have weird shaped bodies but other images are more rounded, and they are described as "rounded" in the literature? -- Colin°^Talk 10:28, 16 June 2021 (UTC)[reply]

Traditionally coronavirus particles are described as pleomorphic (blobs) by negative-stain electron microscopy and this is how they would have appeared to June Almeida (I knew her). Electron microscopes only function in a vacuum and as a result, viruses dry out and shrink on the supporting formvar membrane. The more tricky Cryogenic electron microscopy stops this by using vitreous ice as the supporting medium, but the images still have to be reconstructed by computers using Fourier transforms and other magic. Up until recently (this century) most of the images of viruses in textbooks were negative-stain electron micrographs, which make viruses look two-dimensional. Essentially all images of viruses are artificial. And this is particularly true of the false-colour and false depth of field ones like that red and grey COVID image, which I see everywhere. There is no such thing as a true to life photograph (or micrograph) of a virus. In the days when electron microscopes were routinely used to diagnose infections, it did not matter how distorted the particles were as long as they remained recognisable. The structure of most viruses was determined by X-ray crystallography, which produces images that don't look at all like virus particles. Our understanding of what a virus looks like is a concept, a model even, not a likeness. Graham Beards (talk) 11:17, 16 June 2021 (UTC)[reply]

Bhandari R, Khanna G, Kuhad A (January 2021). "Pharmacological insight into potential therapeutic agents for the deadly Covid-19 pandemic". European Journal of Pharmacology. 890: 173643. doi:10.1016/j.ejphar.2020.173643. PMC 7550915. PMID 33065092. Coronaviruses are pleomorphic, enveloped, or spherical viruses, which have a size ranging from 80 to 120 nm.

In the original source given by the Wikipedia article, it says "Particles are more or less rounded in profile; although there is a certain amount of polymorphism". Although the Wikipedia citation implies this is a paper with eight authors, including Almeida, it turns out to written by an unnamed correspondent (the editor?) and the language is very much second hand and more editorial. So one perhaps wonders how close it is to the authors' observations and opinions. Is this how things were done back then? I see that at 80 to 120 nm, we are talking about something much smaller than the wavelength of visible light.

Your "pleomorphic" description reminds me of "The Dig", where a young archaeologist describes a finding as "rusted lumps" and is pulled up by his mentor about forgetting his training. He revises it to "an amorphous mass of corroded objects". -- Colin°^Talk 13:58, 16 June 2021 (UTC)[reply]

Their being smaller than the wavelength of visible light means of course viruses are too small to have a colour. That Nature report is weird – a cross between a letter and an editorial. It was before even my time (I was still at school) so I don't know if it was the norm. I published a letter in Nature in the early 1980s and it was, as you would expect, written by me and my group. Graham Beards (talk) 14:25, 16 June 2021 (UTC)[reply]

I have just stumbled on this from March 2020 "Grey images of unfamiliar blobs don’t make for persuasive or emotive media content"] -Graham Beards (talk) 16:34, 17 June 2021 (UTC)[reply]

Precious

Nine years!

--Gerda Arendt (talk) 07:07, 22 June 2021 (UTC)[reply]

Hi Graham, just wanted to say I love your micrographs and appreciate your contributions over these many years. From a much less wiki-holic virologist to one who is decidedly more of a fixture around here, I appreciate the good name you give to our profession. Keep up the excellent work :) --Shibbolethink ^{(♔ ♕)} 18:17, 1 July 2021 (UTC)[reply]