Your chance to tell us what you want to read, and why.
Welcome to an experiment. In the article below you will find brief descriptions of three papers that have caught our interest at Nature. Next week, one of our reporters will dig into one of these papers in order to report in more detail about the way the work was done, what the implications are, and more. The question is: which of these possibilities would you like us to investigate further? Tell us in the comments field.
This week: iron in the sea, bacteria in baby worms, and quantum optics in gambling.
One: The dust settles
The photosynthetic plankton that are responsible for most of the oceans' primary productivity need iron, of which the oceans' surface waters are in short supply. This means that the rate at which iron is supplied to the oceans in the form of dust blowing off the continents is an important factor in understanding the carbon cycle.
Thibaut Wagener at the Oceanographic Laboratory of France’s National Centre for Scientific Research in Villefranche sur Mer and his colleagues now report in _Global Biogeochemical Cycles_ that past estimates of the rate at which dust adds iron to the oceans of the southern hemisphere may be much too high. The researchers collected and analysed dust on cruises in the southern Pacific and Indian Oceans, and as a result of their findings argue that upwelling plumes of ocean water rather than wind-borne dust provide the iron in these regions.
Two: A nice set of bugs for the kids
Earthworms of the family Lumbricidae bequeath their offspring a gift of Acidovorax-like bacteria; at least some species deposit them directly into the egg capsules where embryos will develop. Writing in the _ISME Journal_, Seana Davidson and David Stahl of the University of Washington in Seattle report their finding that the Acidovorax-like bacteria were selectively recruited to a small canal in the earthworm's various segments where they lingered until excretory organs, called nephridia, developed far enough for the bacteria to colonize them. Given the bacteria-rich soil in which the worm lives, this selectivity for its symbiont suggests that the embryos fend off colonization attempts by other microbes.
Three: Schroedinger's roulette wheel
How can online gamblers be sure that the casino isn’t cheating? They can’t. The quantum gambling machine devised by Yi-Sheng Zhang and colleagues at the University of Science and Technology of China in Hefei, though, could put an end to that. In their system, reported in _Europhysics Letters_ , the casino places a particle in a quantum superposition, where it is in two ‘boxes’ at once until the gambler opens one of them, ‘collapsing’ the particle into one or other box with equal probability. The gambler bets against the casino about which box the particle will be in.
The casino subsequently sends the gambler the unselected box for checking: the quantum rules mean that if the casino tampered with the probabilities to bias the result, the gambler has a chance of finding out. If there is a hefty penalty for such cheating, the chance of the casino increasing its winnings this way is negligible.
Zhang and colleagues have demonstrated the game using photons in superpositions of polarization states. Three detectors measure the result: two read the photon’s state, and the third checks for tampering.
If you believe the many-worlds interpretation of quantum mechanics, does this mean that everyone's a winner?