Quantum-enhanced sensing of a single-ion mechanical oscillator.

Special quantum states are used in metrology to achieve sensitivities below the limits established by classically behaving states. In bosonic interferometers, squeezed states, number states and 'Schrödinger cat' states have been implemented on various platforms and have demonstrated improved measurement precision over interferometers using coherent states. Another metrologically useful state is an equal superposition of two eigenstates with maximally different energies; this state ideally reaches the full interferometric sensitivity allowed by quantum mechanics.

Chromosomal contact permits transcription between coregulated genes.

Transcription of coregulated genes occurs in the context of long-range chromosomal contacts that form multigene complexes. Such contacts and transcription are lost in knockout studies of transcription factors and structural chromatin proteins. To ask whether chromosomal contacts are required for cotranscription in multigene complexes, we devised a strategy using TALENs to cleave and disrupt gene loops in a well-characterized multigene complex.