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Spectroscopy that combines the accuracy of a frequency comb with the ease of use of a tunable, external cavity diode laser is demonstrated, enabling precise dispersion measurements of microresonator modes.

Non-photochemical quenching (NPQ) protects plants from photodamage. A mutant lacking LHCII, the main antenna complex of plants, shows that NPQ mainly occurs in LHCII, but there is an additional quenching site within the Photosystem II core.

Evergreen conifers rely on ‘sustained quenching’ to protect their photosynthetic machinery during long, cold winters. Here, Bag et al. show that direct energy transfer (spillover) from photosystem II to photosystem I triggered by loss of grana stacking in chloroplast is the major component of sustained quenching in Scots pine.

The magnetic fields of Earth and Jupiter, along with those of rapidly rotating, low-mass stars, are generated by convection-driven dynamos that may operate similarly, although the field strengths vary. The critical factor unifying field generation in such different objects, while still causing a large variation, has been unclear. This paper reports an extension of a scaling law derived from geodynamo models to rapidly rotating stars. The unifying principle is that the energy flux available for generating the magnetic field sets the field strength.

A tiny disc-like structure on a silicon chip is simply illuminated by a conventional laser diode, and the resulting interaction between the laser light and the resonator gives rise to an optical frequency comb that emits in the infrared. The simplicity of the scheme, and the reduction in size, cost and power, should enhance the utility of optical frequency combs in a broad number of fields.

Optical frequency combs are vital tools for precision measurements, and extending them further into the mid-infrared 'molecular fingerprint' range will open new avenues for spectroscopy. Using crystalline microresonators, Wang et al. demonstrate Kerr combs at 2.5 μm as a promising route into the mid-infrared.

By using an ultrastable oscillator based on a cryogenic Si cavity, the fractional instability of two Sr optical lattice clocks at 1 s reaches 4.8 × 10⁻¹⁷ and 3.5 × 10⁻¹⁷ through anti-synchronous and synchronous comparisons, respectively.

When exposing a tungsten crystal to intense light, the travel times of emitted electrons differ by 110 attoseconds, depending on whether they were originally tightly bound to one atom in the crystal or delocalized over many atoms. This ability to directly probe fundamental aspects of solid-state electron dynamics could aid the further development of modern technologies such as electronics, information processing and photovoltaics.

Using two coherent broadband fibre-laser frequency comb sources, a coherent laser ranging system for absolute distance measurements is demonstrated. Its combination of precision, speed and long range may prove particularly useful for space-based sciences.

Based on observations in crystalline MgF₂ and planar Si₃N₄ microresonators, scientists reveal that the existence of multiple and broad-beat notes in a Kerr-frequency comb is due to the formation dynamics of the comb itself. This work identifies the conditions requires for low-phase-noise performance and also helps to elucidate a number of yet-unexplained phenomena.

Garry Cutting and colleagues report a genome-wide association and linkage study for loci that affect lung disease severity in cystic fibrosis. They identify two loci that influence lung function in individuals with cystic fibrosis.

Using two independent laser frequency combs to calibrate an astronomical spectrometer, researchers demonstrate a stability of ~1 cm s^–1, which is required for detecting low-mass rocky exoplanets around Sun-like stars.

Lisa Strug and colleagues report a genome-wide association study for meconium ileus in individuals with cystic fibrosis. Conventional genome-wide approaches identified variants in SLC26A9 and SLC6A14 associated with meconium ileus. The authors also performed a hypothesis-driven genome-wide association study (HD-GWAS) that upweighted 3,814 SNPs within 10 kb of 155 genes expressed in the apical plasma membrane. The HD-GWAS identified variants near SLC9A3 associated with meconium ileus.