VX (C11H26NO2PS) is a colourless, odourless, oily liquid under room temperatures. It is a member of the V-series of nerve agents, and is an extremely potent poison - only 0.01 grams of it is needed to kill a person by skin contact. VX was recently implicated in the assassination of Kim Jong-nam, the half-brother of the North Korean leader Kim Jong-un, in Malaysia.
VX is a potent inhibitor of acetylcholinesterase, which breaks down the neurotransmitter acetylcholine into acetic acid and choline. The normal function of the enzyme is to regulate the concentration of acetylcholine within the synaptic cleft, so as to control the frequency of binding of acetylcholine to cholinergic receptors on the postsynaptic cell membrane and hence the transmission of impulses across the synapse.
Consequently, the inhibition of acetylcholinesterase results in a rapid increase in the synaptic concentration of acetylcholine, as the presynaptic knob continues to synthesise it and secrete it into the synaptic cleft. As a result, the cholinergic receptors on the postsynaptic cell membrane are continually stimulated, and a rapid series of action potentials are triggered. This results in muscle spasms and eventual paralysis, leading to death by asphyxiation due to paralysis of the diaphragm.
VX exposure is usually treated using an injection of atropine and pralidoxime. Atropine inhibits certain cholinergic receptors, reducing the binding of acetylcholine to receptors and thus the triggering of action potentials. On the other hand, one end of pralidoxime binds to acetylcholinesterase and the other binds to the phosphate group of VX, which causes the VX molecule to detach from the enzyme together with the pralidoxime molecule (see below). This restores the ability of acetylcholinesterase to hydrolyse acetylcholine, hence reducing its synaptic levels.
VX is synthesised from phosphorus trichloride over multiple steps; first, it is methylated, reacted with ethanol, then transesterified with N,N-diisopropylaminoethanol to produce QL. This is then oxidised with sulfur, and isomerised via heating to produce VX.
The word meme was originally coined in the 1970s by sociobiologist, Richard Dawkins, from the ancient Greek for imitation.
He used it to describe how ideas and symbols propagate through a culture like genes through a population.
With the advent of the Internet, the process became directly observable in how jokes and images were popularized at lightning speed and soon the word came to refer to a certain kind of image.
So ‘meme’ not only describes how words become part of language, the word is a meme itself. As it turns out, there’s a word for words that describe themselves: ‘autological’.
Spread the word! ;)
From the TED-Ed Lesson Where do new words come from? - Marcel Danesi
Animation by TOGETHER
My boyfriend, @inlove-with-a-spine, is very uninformed about Southeast Asian fruits (he only knows durian) which inspired me to find these online.
I’m pretty sure the names are different in other Southeast Asian countries, though.
From left to right (in Indonesian):
Duku
Jambu monyet
Jeruk
Lengkeng
Kedondong
Manggis
Rambutan
Nangka
Salak
Sawo
The anime ‘Romeo’s Blue Skies’ is based on a book about a true event which happened in the south of Switzerland unti the 19th century: young boys being sold to Milano to work there as chimney sweepers. There is also a German movie about it called ‘Die Schwarzen Brüder’ [the Black Brothers]. You can watch the trailer here
The CDC study, Alkyl Mercury-Induced Toxicity: Multiple Mechanisms of Action, appeared last month in the journal, Reviews of Environmental Contamination and Toxicology. The 45-page meta-review of relevant science examines the various ways that mercury harms the human body. Its authors, John F. Risher, PhD, and Pamela Tucker, MD, are researchers in the CDC’s Division of Toxicology and Human Health Sciences, Agency for Toxic Substances and Disease Registry.
“This scientific paper is the one of most important pieces of research to come out of the CDC in a decade,” Paul Thomas, M.D., a Dartmouth-trained pediatrician who has been practicing medicine for 30 years, said. “It confirms what so many already suspected: that public health officials have been making a terrible mistake in recommending that we expose babies and pregnant women to this neurotoxin. I regret to say that I gave these shots to children. The CDC led us all to believe that it was perfectly safe.”
Among the findings of the CDC’s new study:
Methylmercury, the highly-regulated neurotoxin found in fish, and ethylmercury (found in medical products, including influenza and tetanus vaccines, ear drops and nasal sprays) are similarly toxic to humans. Methylmercury and ethylmercury share common chemical properties, and both significantly disrupt central nervous system development and function.
Thimerosal is extremely toxic at very low exposures and is more damaging than methylmercury in some studies. For example, ethylmercury is even more destructive to the mitochondria in cells than methylmercury.
The ethylmercury in thimerosal does not leave the body quickly as the CDC once claimed, but is metabolized into highly neurotoxic forms.
I have posted about survivorship bias and how it affects your career choices: how a Hollywood actor giving the classic “follow your dreams and never give up” line is bad advice and is pure survivorship bias at work.
When I read up on the wikipedia page, I encountered an interesting story:
During WWII the US Air Force wanted to minimize bomber losses to enemy fire. The Center for Naval Analyses ran a research on where bombers tend to get hit with the explicit aim of enforcing the parts of the airframe that is most likely to receive incoming fire. This is what they came up with:
So, they said: the red dots are where bombers are most likely to be hit, so put some more armor on those parts to make the bombers more resilient. That looked like a logical conclusion, until Abraham Wald - a mathematician - started asking questions:
- how did you obtain that data? - well, we looked at every bomber returning from a raid, marked the damages on the airframe on a sheet and collected the sheets from all allied air bases over months. What you see is the result of hundreds of those sheets. - and your conclusion? - well, the red dots are where the bombers were hit. So let’s enforce those parts because they are most exposed to enemy fire. - no. the red dots are where a bomber can take a hit and return. The bombers that took a hit to the ailerons, the engines or the cockpit never made it home. That’s why they are absent in your data. The blank spots are exactly where you have to enforce the airframe, so those bombers can return.
This is survivorship bias. You only see a subset of the outcomes. The ones that made it far enough to be visible. Look out for absence of data. Sometimes they tell a story of their own.
BTW: You can see the result of this research today. This is the exact reason the A-10 has the pilot sitting in a titanium armor bathtub and has it’s engines placed high and shielded.
‘Art is the spark, the illumination which is socially significant for it brings about understanding’ – Gerard Sekoto (1913–1993)
Gerard Sekoto was born in Botshabelo, Mpumalanga province, in 1913, the year in which the Natives Land Act dispossessed many black South Africans of their ancestral lands. In 1938 Sekoto moved to Sophiatown, Johannesburg. He held his first solo exhibition the following year, and in 1940 the Johannesburg Art Gallery purchased his work Yellow Houses – A Street in Sophiatown (1939–1940). It was the first painting by a black South African artist to be acquired by a South African art institution, although Sekoto had to pose as a cleaner to see his own painting hanging in the gallery.
Sekoto based this painting, titled Song of the Pick (1946), on a photograph taken in the 1930s of black South African workers labouring under the watchful eye of a white foreman standing behind them. However, in his painting the dynamic has changed. Sekoto has enhanced the grace and power of the labourers, turning them to confront the small and puny figure of the overseer, who appears about to be impaled by their pickaxes.
Sekoto painted this work in the township of Eastwood in Pretoria, shortly before moving to Paris in what became a lifelong exile from South Africa. During the 1980s, postcard-sized reproductions of this iconic painting were widely distributed in South Africa, as both a badge of honour and a source of inspiration in the struggle against apartheid.
Explore a diverse range of art stretching back 100,000 years in our exhibition South Africa: the art of a nation (27 October 2016 – 26 February 2017).
Exhibition sponsored by Betsy and Jack Ryan
Logistics partner IAG Cargo
Song of the Pick, 1946. Image © Iziko Museums of South Africa, Art Collections, Cape Town. Photo by Carina Beyer.
Song of the Pick was based on this image, taken by photographer Andrew Goldie in the 1930s.
Orchid mantises—particularly juveniles—seem aptly named. They’re predominantly white with pink or yellow accents, similar to some orchids and other flowers, and their four hind legs are lobed, like petals. But if you search for an exact floral counterpart, as behavioral ecologist James O’Hanlon did, you probably won’t find one. “I spent forever looking for a flower that they look just like,” he says, to no avail.
As it turns out, rather than mimicking one floral species, the insect instead may embody a “generic or an average type of flower” in order to attract bees and other pollinating insects as prey.
What’s more, as far as O’Hanlon can tell, it’s the only animal on record that “takes on the guise of a whole flower blossom” as a predatory strategy.
Learn more here.
A reblog of nerdy and quirky stuff that pique my interest.
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