The physics of mixing solutions, though a venerated part of scientific history (think alchemy), is all too often over-looked in today's hyper-paced laboratory environment.  The technology behind the BioShake iQ offers precise control of orbital diameter and rotational speed so that all conceivable well shapes/sizes and sample volumes can be efficiently mixed in a minimum of time.  See this instrument in action and how various plate formats and sample volumes are reliably mixed.

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Once again, our post-doctoral protagonist, Dr. Green faces an interesting challenge to her daily routine. This time the lab's precision electronic balance has gone on the fritz.  And she needs to quickly determine which of her knockout mice is exhibiting an obesity-related gene.  In this case, only 1 of the 27 mice in the colony is actually exhibiting the phenotype of increased body weight.  By chance, or perhaps because of her phenomenal experimental technique, the remaining 26 mice are nearly the same weight.  Dr. Green was able to rummage through a storage room and locate a classic 2-pan balance (i.e. with opposing pans in which two objects' weights can be directly compared).  What are the fewest rounds of measurements required to precisely determine the obese mouse? For example - if there were 8 mice you might say 3 rounds (first, 4 mice against 4 mice, then take the heavier group and divide into groups of 2 to be measured, and finally take the remaining 2 and compare them directly to determine the heaviest mouse).