Volume 539 Issue 7628



News Features

News & Views

Single-molecule instant replay p.170

A nanoscale imaging method that uses ultrashort light pulses to initiate and follow the motion of a single molecule adsorbed on a solid surface opens a window onto the physical and chemical dynamics of molecules on surfaces. See Letter p.263

doi: 10.1038/539170a

Genomic remodelling in the primate brain p.171

In many mammals, the gene Ostn is expressed in muscles and bones. The discovery that the primate OSTN gene has been repurposed to also act in neurons provides clues to how humans evolved their cognitive abilities. See Article p.242

doi: 10.1038/539171a

Bad neighbours cause bad blood p.173

Expression of a blood-cancer-associated genetic mutation in the non-blood cells of the bone marrow is sufficient to cause blood cancer in mice. This finding could point to new approaches to treating an often-fatal disease. See Letter p.304

doi: 10.1038/nature19479

Eighty years of stress p.175

The discovery in 1936 that rats respond to various damaging stimuli with a general response that involves alarm, resistance and exhaustion launched the discipline of stress research.

doi: 10.1038/nature20473

A strange kind of liquid p.176

Interactions between the magnetic dipoles of dysprosium atoms in an ultracold gas can produce a 'self-bound' droplet. This provides a useful isolated system for probing the quantum-mechanical properties of ultracold gases. See Letter p.259

doi: 10.1038/539176a

Neural interfaces take another step forward p.177

Two monkeys subjected to a spinal-cord injury that paralysed one leg have regained the ability to walk, thanks to technology that re-establishes communication between the brain and spinal cord. See Letter p.284

doi: 10.1038/539177a


Balancing selection shapes density-dependent foraging behaviour p.254

Natural isolates of Caenorhabditis elegans nematodes differ in their sensitivity to the anti-exploratory pheromone icas#9, yielding two distinct foraging strategies that possess different survival advantages depending on environmental conditions such as food distribution.

doi: 10.1038/nature19848


Tracking the ultrafast motion of a single molecule by femtosecond orbital imaging p.263

Watching a single molecule move calls for measurements that combine ultrafast temporal resolution with atomic spatial resolution; this is now shown to be possible by combining scanning tunnelling microscopy with lightwave electronics, through a technique that involves removing a single electron from the highest occupied orbital of a single pentacene molecule in a time window shorter than an oscillation cycle of light.

doi: 10.1038/nature19816

Amide-directed photoredox-catalysed C–C bond formation at unactivated sp3 C–H bonds p.272

Carbon–carbon (C–C) bond formation is paramount in the synthesis of biologically relevant molecules, modern synthetic materials and commodity chemicals such as fuels and lubricants. Traditionally, the presence of a functional group is required at the site of C–C bond formation. Strategies that allow C–C bond formation at inert carbon–hydrogen (C–H) bonds enable access to molecules that would otherwise be inaccessible and the development of more efficient syntheses of complex molecules. Here we report a method for the formation of C–C bonds by directed cleavage of traditionally non-reactive C–H bonds and their subsequent coupling with readily available alkenes. Our methodology allows for amide-directed selective C–C bond formation at unactivated sp3 C–H bonds in molecules that contain many such bonds that are seemingly indistinguishable. Selectivity arises through a relayed photoredox-catalysed oxidation of a nitrogen–hydrogen bond. We anticipate that our findings will serve as a starting point for functionalization at inert C–H bonds through a strategy involving hydrogen-atom transfer.

doi: 10.1038/nature19810

A basal ganglia circuit for evaluating action outcomes p.289

In mice, glutamatergic globus pallidus neurons projecting to the lateral habenula (GPh neurons) bi-directionally encode positive and negative prediction error signals that are critical for outcome evaluation and are driven by a subset of basal ganglia circuits.

doi: 10.1038/nature19845