Eating for zillions, and a gold rush

Two weeks' pickings from Rocket Science, where I'm catching up after a long period indulging myself over at Project Gutenberg, and several days' worth of technical difficulties in our internet connection.  (It's heck living out in the boonies.)

First, an article about the surprisingly complicated study of breast milk.  It seems that a mother modifies the content of her milk in response to a variety of signals, including (possibly) the sex of her child or the
baby's having caught an infection.  Also, something that caught my eye, as I'm always interested in the emerging science of the gut:

Some human milk oligosaccharides—simple sugar carbohydrates—were recently discovered to be indigestible by infants. When my son was nursing, those oligosaccharides weren’t meant for him. They were meant for bacteria in his gut, which thought they were delicious. My wife was, in a sense, nursing another species altogether, a species that had been evolutionarily selected to protect her child. (A relationship immortalized in the paper titled “Human Milk Oligosaccharides: Every Baby Needs a Sugar Mama.”) In effect, as Hinde and UC-Davis chemist Bruce German have written, “mothers are not just eating for two, they are actually eating for 2 × 10¹¹ (their own intestinal microbiome as well as their infant’s)!”

On a completely unrelated note, earthquakes may stimulate the formation of nearly instantaneous veins of gold.  Small earthquakes can cause sudden local depressurations, with an interesting effect on fluids circulating nearby:

When mineral-laden water at around 390 °C is subjected to that kind of pressure drop, Weatherley says, the liquid rapidly vaporizes and the minerals in the now-supersaturated water crystallize almost instantly—a process that engineers call flash vaporization or flash deposition. The effect, he says, “is sufficiently large that quartz and any of its associated minerals and metals will fall out of solution”.