5 ms·

Reminds me of one of my favourite stories: > A US nuclear laboratory is said to maintain a "heavy dog"--fed with heavy water and "heavy" food, and with the hea

by genmon 7y ago

Reminds me of one of my favourite stories: > A US nuclear laboratory is said to maintain a "heavy dog"--fed with heavy water and "heavy" food, and with the heavy isotope deuterium replacing normal hydrogen throughout the whole body. -- New Scientist, 1976 [1] And: > [it] would be invisible to a MRI scanner. The dog would still be clearly visible to the naked eye so apart from confusing the staff operating the scanner I can see no advantage to this. -- source [2] [1] https://books.google.co.uk/books?id=AhC9t3Q3YMcC&lpg=PA480&ots=vIjfN55PE-&dq=%22heavy%20dog%22%20deuterium&pg=PA480#v=onepage&q=%22heavy%20dog%22%20deuterium&f=false https://books.google.co.uk/books?id=AhC9t3Q3YMcC&lpg=PA480&o... [2] https://scicommstudios.wordpress.com/2012/01/08/hydrogen/ https://scicommstudios.wordpress.com/2012/01/08/hydrogen/

nabla9 7y ago
Unlikely to be true. Deuterium is toxic in high concentrations. It slows down metabolism and inhibits cell division. Mammals die within week if half of the water in the body is replaced with deuterium oxide.
- tyingq 7y ago
  From the story: "This is obviously bollocks, and not even the dog’s bollocks."
PhasmaFelis 7y ago
Unfortunately the dog would die before reaching that point; mammals die around the point when 50% of their H2O is replaced with D2O. It's a great story, though.
jcims 7y ago
I don't know about heavy pups but that New Scientist issue is a lot of fun to scroll through. Surprisingly relevant content in parts for being 43 years old.
Pulcinella 7y ago
Turns out being invisible to MRI is not without it’s advantages. NMR (MRI for molecules) uses deuterated solvents so the hydrogen signal from the solvent doesn’t overwhelm the signal from the sample molecules.
kabdib 7y ago
About 20 years ago my dad was doing research (at the U of Georgia) that traced how a peptide was metabolized by grasshoppers. They used an isotope of carbon with a 20 minute half-life (C11), but also needed to ensure that the radiation from Carbon-14 and other isotopes was very, very low. Essentially they needed grasshoppers with stable versions of carbon, which you're not going to get from the wild. So they grew plants and grasshoppers in a sealed environment, with CO2 (and probably other carbon sources) from oil. Since the hydrocarbons in the oil are millions of years old, the carbon is essentially exhausted of radioactive isotopes. If you carbon dated one of those grasshoppers it would have seemed tens of thousands of years old...

by genmon 7y ago

nabla9 7y ago

Unlikely to be true. Deuterium is toxic in high concentrations. It slows down metabolism and inhibits cell division. Mammals die within week if half of the water in the body is replaced with deuterium oxide.

tyingq 7y ago
From the story: "This is obviously bollocks, and not even the dog’s bollocks."

PhasmaFelis 7y ago

Unfortunately the dog would die before reaching that point; mammals die around the point when 50% of their H2O is replaced with D2O. It's a great story, though.

jcims 7y ago

I don't know about heavy pups but that New Scientist issue is a lot of fun to scroll through. Surprisingly relevant content in parts for being 43 years old.

Pulcinella 7y ago

Turns out being invisible to MRI is not without it’s advantages. NMR (MRI for molecules) uses deuterated solvents so the hydrogen signal from the solvent doesn’t overwhelm the signal from the sample molecules.

kabdib 7y ago

About 20 years ago my dad was doing research (at the U of Georgia) that traced how a peptide was metabolized by grasshoppers. They used an isotope of carbon with a 20 minute half-life (C11), but also needed to ensure that the radiation from Carbon-14 and other isotopes was very, very low. Essentially they needed grasshoppers with stable versions of carbon, which you're not going to get from the wild. So they grew plants and grasshoppers in a sealed environment, with CO2 (and probably other carbon sources) from oil. Since the hydrocarbons in the oil are millions of years old, the carbon is essentially exhausted of radioactive isotopes. If you carbon dated one of those grasshoppers it would have seemed tens of thousands of years old...