Sustainability at the crossroads p.569

A look back at 2021 through the Sustainable Development Goals.

doi: 10.1038/d41586-021-03781-z

How severe are Omicron infections? p.577

As cases spread and countries plan their response, researchers await crucial data on the severity of the disease caused by the coronavirus variant.

doi: 10.1038/d41586-021-03794-8

Evidence of racism found at prestigious London university p.578

London School of Hygiene & Tropical Medicine has pledged to revise equity and diversity policies after a review highlighted racial inequality among students and staff.

doi: 10.1038/d41586-021-03755-1

Omicron blindspots: why it’s hard to track coronavirus variants p.579

Researchers are rapidly sequencing the genomes of virus samples worldwide, but shortcomings in the global surveillance system make the task a challenge.

doi: 10.1038/d41586-021-03698-7

How COVID vaccines shaped 2021 in eight powerful charts p.580

The extraordinary vaccination of more than four billion people, and the lack of access for many others, were major forces this year — while Omicron’s arrival complicated things further.

doi: 10.1038/d41586-021-03686-x

The best science images of 2021 p.584

A helicopter on Mars, human–monkey embryos, volcanic ash and more.

doi: 10.1038/d41586-021-03521-3

Nature's 10: Ten people who helped shape science in 2021 p.591

doi: 10.1038/d41586-021-03621-0

Alternatives to standard quantum theory ruled out p.607

Standard quantum theory contains square roots of negative numbers. But how essential are these ‘imaginary’ numbers? A way of disproving analogous theories that omit them has been proposed — and confirmed experimentally.

doi: 10.1038/d41586-021-03678-x

Stomach cancer gets a triple punch of therapy p.608

Harnessing immune cells to target tumours is a growing trend. The results of a clinical trial combining such treatment with other standard therapies for gastric cancer have altered medical practice — and more changes are to come.

doi: 10.1038/d41586-021-03458-7

Low-power light modifies electron microscopy p.610

An optical device designed to control the properties of electron waves inside an electron microscope demonstrates that clever platforms for integrated photonics need not be powered by expensive laser systems.

doi: 10.1038/d41586-021-03767-x

Gut clues to weight gain after quitting smoking p.611

Research has uncovered factors that underlie the weight gain associated with cessation of smoking. Here, scientists consider the implications of this finding from the perspectives of gut biology and of smoking.

doi: 10.1038/d41586-021-03548-6

Clever substitutions reveal magnetism in zigzag graphene nanoribbons p.613

The inclusion of nitrogen atoms stabilizes the zigzag edges of carbon-based nanoribbons, enabling the ribbons to be decoupled from a substrate and providing a probe for their unconventional magnetism.

doi: 10.1038/d41586-021-03768-w

What surveys really say p.614

Increasing the sample size of a survey is often thought to increase the accuracy of the results. However, an analysis of big surveys on the uptake of COVID-19 vaccines shows that larger sample sizes do not protect against bias.

doi: 10.1038/d41586-021-03604-1

Gravity, AlphaFold and neural interfaces: a year of remarkable science p.617

Highlights from News & Views published this year.

doi: 10.1038/d41586-021-03730-w

Very-high-frequency oscillations in the main peak of a magnetar giant flare p.621

doi: 10.1038/s41586-021-04101-1

Quantum theory based on real numbers can be experimentally falsified p.625

doi: 10.1038/s41586-021-04160-4

Programmable interactions and emergent geometry in an array of atom clouds p.630

doi: 10.1038/s41586-021-04156-0

Resonance from antiferromagnetic spin fluctuations for superconductivity in UTe2 p.636

doi: 10.1038/s41586-021-04151-5

Quantum anomalous Hall effect from intertwined moiré bands p.641

doi: 10.1038/s41586-021-04171-1

Spin splitting of dopant edge state in magnetic zigzag graphene nanoribbons p.647

doi: 10.1038/s41586-021-04201-y

Integrated photonics enables continuous-beam electron phase modulation p.653

doi: 10.1038/s41586-021-04197-5

Dynamic spatial progression of isolated lithium during battery operations p.659

doi: 10.1038/s41586-021-04168-w

High-entropy polymer produces a giant electrocaloric effect at low fields p.664

doi: 10.1038/s41586-021-04189-5

Rapid microbial methanogenesis during CO₂ storage in hydrocarbon reservoirs p.670

doi: 10.1038/s41586-021-04153-3

The power of genetic diversity in genome-wide association studies of lipids p.675

doi: 10.1038/s41586-021-04064-3

Cortical responses to touch reflect subcortical integration of LTMR signals p.680

doi: 10.1038/s41586-021-04094-x

Mechanical actions of dendritic-spine enlargement on presynaptic exocytosis p.686

doi: 10.1038/s41586-021-04125-7

Collective durotaxis along a self-generated stiffness gradient in vivo p.690

doi: 10.1038/s41586-021-04210-x

Unrepresentative big surveys significantly overestimated US vaccine uptake p.695

doi: 10.1038/s41586-021-04198-4

Immunogenicity and efficacy of          heterologous ChAdOx1–BNT162b2 vaccination p.701

doi: 10.1038/s41586-021-04120-y

Antigen-presenting innate lymphoid cells orchestrate neuroinflammation p.707

doi: 10.1038/s41586-021-04136-4

Gut microbiota modulates weight gain in mice after discontinued smoke exposure p.713

doi: 10.1038/s41586-021-04194-8

A hormone complex of FABP4 and nucleoside kinases regulates islet function p.720

doi: 10.1038/s41586-021-04137-3

The KEYNOTE-811 trial of dual PD-1 and HER2 blockade in HER2-positive gastric cancer p.727

doi: 10.1038/s41586-021-04161-3

ecDNA hubs drive cooperative intermolecular oncogene expression p.731

doi: 10.1038/s41586-021-04116-8

Sex-specific chromatin remodelling safeguards transcription in germ cells p.737

doi: 10.1038/s41586-021-04208-5

A conserved mechanism for regulating replisome disassembly in eukaryotes p.743

doi: 10.1038/s41586-021-04145-3

Activation of homologous recombination in G1 preserves centromeric integrity p.748

doi: 10.1038/s41586-021-04200-z

β-NAD as a building block in natural product biosynthesis p.754

doi: 10.1038/s41586-021-04214-7

Structures of the σ2 receptor enable docking for bioactive ligand discovery p.759

doi: 10.1038/s41586-021-04175-x