Tossup

Preventing the use of rotationally symmetric static fields in this technique can help overcome a limit set by Scherzer’s theorem. The “spot-scan” technique is sometimes used to prevent beam-induced motion in this larger technique. Samples in this technique may use heavy metals such as tungsten and osmium to undergo a “negative stain.” The development of a form of this technique, for which Dubochet, Frank, and Henderson were awarded the 2017 Nobel Prize in Chemistry, generated a “resolution revolution.” (-5[1])In a form of this technique, the observed specimen is embedded in vitrified ice before being mounted (10[1])on a grid and fixed via plunging in liquid ethane. For 10 points, name this imaging technique that comes in “scanning,” (10[1])“transmission,” and “cryogenic” types. (10[1])■END■ (0[1])

ANSWER: electron microscopy [or EM; accept cryogenic electron microscopy or cryo-EM or transmission electron microscopy or TEM or scanning electron microscopy or SEM; prompt on microscopy]
<Minnesota A, Chemistry>
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Summary

TournamentEditionTUHConv. %Neg %Average Buzz
Lower Mid-Atlantic2025-02-01683%17%116.00
Midwest2025-02-016100%50%96.50
Northeast2025-02-01475%25%109.33
Overflow2025-02-01475%25%71.67
Pacific Northwest2025-02-012100%50%118.00
UK2025-02-011090%0%91.78
Upper Mid-Atlantic2025-02-01888%0%94.14