This beautiful image is of the small-spotted catshark, and is by Hans Hillewaert (Wikimedia). They are carnivores and hunt on the seabed, where I think vision is poor. So they have evolved to hunt, in part, by sensing the electric fields due to their prey. This was shown over 50 years ago, with some beautiful work by AJ Kalmijn. There is a lovely Scientific American article on this, by RD Fields, in 2007.
Category Archives: Science
The difference between insanity and genius is measured only by success and failure
The title is a quote by the manga artist Masashi Kishimoto. It is one of many quotes linking insanity and genius, one of them dating all the way back to Aristotle. But now, finally, we can quantify how similar insanity and madness, it is: 0.5810. This may not look that high but insanity is closer to madness than sanity, sanity and madness only have a similarity of 0.4114.
A toy app to calculate Stokes-Einstein diffusion constants
The one formula that I use above all others in my research is that for the diffusion constant of a dilute species in a fluid, called the Stokes-Einstein (or sometimes Stokes-Einstein-Sutherland) equation:
DSE = kT/(6 π η RH)
The diffusion constant DSE of something with a size (hydrodynamic radius) RH is just the thermal energy kT divided by 6π times the product of the viscosity of the fluid, η, and the hydrodynamic radius, RH. All it tells you is that large species in viscous fluids diffuse more slowly than small species in less viscous fluids.
Jumping on the LLM bandwagon with a RAGbot to answer questions on my lecture notes
Unless you have just emerged from a cave you will have heard of ChatGPT, Google Gemini, Claude, etc – collectively LLMs (Large Language Models, also called Generative AI models). Wikipedia calls Google Gemini a generative artificial intelligence chatbot. They are fancy and powerful, and touching many parts of the world including education. My employer (as I am sure many universities are) is trying to keep up.
Conservative and Labour politicians spreading misinformation they just don’t understand
Andrew Gwynne is a Labour MP and Parliamentary Under-Secretary of State for Public Health and Prevention in the current Labour government. He is spreading misinformation about COVID transmission on behalf of either civil servants or the NHS’s IPC (Infection Prevention and Control) cell. See this Bluesky post by Al Haddrell which has a letter signed by Gwynne and to an MP (Tim Farron) who was written to Gwynne of behalf of a constituent.
The Welsh ambulance service declares a “critical incident” and still the NHS in Wales does not “follow the science”
A couple of days ago – 30th December 2024 – the Welsh ambulance service declared a critical incident. According to the Wales Online report, the head of the ambulance service, Stephen Sheldon said
“It is very rare that we declare a critical incident, but with significant demand on our service and more than 90 ambulances waiting to hand over patients outside of hospital, our ability to help patients has been impacted.”
Welsh (and English) hospitals are under great pressure from a “quad-demic” of flu, RSV, COVID and norovirus. Three of these diseases are transmitted across the air: flu, RSV and COVID. The fourth: norovirus, is food and waterborne. This pressure has prompted the introduction of both visiting restrictions and masking requirements in Welsh hospitals.
The visiting restrictions for Swansea’s hospitals near where my mother lives are here. If you follow the link you will see a large picture of surgical masks, so looks like visitors to hospitals will be handed surgical masks, to try and reduce the spread of flu (and RSV, COVID etc).
Blog post of the 32,524th best academic on the planet!
I would like to take a break from being rude about university league tables to talk about a league table that is (too) good for my ego. This is of publishing academics and ranks me at 32,524 (data here). Being 32,524th may not sound impressive but the world’s population is over 7 billion – admittedly most of the 7 billion don’t publish academic papers. It also may be highest rank of anyone in my School at Surrey (but not the highest rank of anyone at Surrey). It is also higher than my sister’s rank*.
Combining data on the filtration efficiency of masks, with epidemiology studies of mask use
The previous post was perhaps a bit of a moan about epidemiologists and medics focusing on randomised controlled trials (RCTs) and observational studies, to the exclusion of absolutely every other study. This was in the context of using masks to reduce the probability that you catch COVID-19. But moaning is not very constructive. A better approach is to say: OK so epidemiologists are not combining epidemiology data with other data, but there is nothing to stop you doing this. So what can be done if data from epidemiology studies are combined with data of other types?
Viruses to the rescue?
Viruses have a bad press, and this is not surprising. COVID-19 is caused by the virus SARS-CoV-2 and the pandemic is estimated to have caused at least 15 million deaths. But our planet Earth hosts enormous numbers of viruses and not even one in a million infects us humans, it is just that these less than one in a million viruses are the ones we mostly care about. So 99.999% + of Earth’s viruses infect other organisms. When they infect us and make us sick that is bad but when they infect an organism we don’t like that could be good.
Is labelling foods “ultraprocessed” junk science?
There have been stories suggesting “ultraprocessed” foods are bad for you. This made me curious about what actually is a ultraprocessed food? How are ultraprocessed foods defined? So I did Googling* and, oddly, the British Heart Foundation has a detailed page on them that links to this document on the “NOVA classification”. The NOVA classification seems to be a standard*. I am no food scientist but this is a weird document.
Chance & Necessity 
