Question

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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Buzzes

PlayerTeamOpponentBuzz PositionValue
Andrew MessersmithBrandeis BBrown A77-5
Jonathan HuangMIT AHarvard A9410
Jerry ZhangHarvard BTufts A11510
Mason YuBrown ABrandeis B11910
Khugan ChanUMass BostonBU1200

Summary

Lower Mid-Atlantic2025-02-01Y683%0%17%116.00
Midwest2025-02-01Y6100%0%50%96.50
Northeast2025-02-01Y475%0%25%109.33
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