Volume 496 Issue 7444, 11 April 2013

Everyone should wish Germany well in its great experiment in renewable energy.

A court ruling to remove age limits on access to emergency contraception must prevail.

The idea of applying geoengineering research to mitigate climate change has not been thought through, argues Clive Hamilton.

The week in science: Investigation launched into muzzled Canadian scientists; Marcia McNutt takes the helm at Science; and the origins of antimatter are probed.

Researchers suspect H7N9 virus is in bird markets as human cases rise rapidly.

Researchers get to grips with effects of heat, drought and storms on carbon release.

Horses, dogs and even a tiger have received the unproven therapies. Now, drug regulators plan to weigh in.

US supply stockpile for combating bioterror attacks and pandemics feels the strain of funding cuts.

As US Supreme Court justices prepare to hear arguments in Myriad Genetics case, observers are debating the impact of the outcome on personal genomics.

Technique to make tissue transparent offers three-dimensional view of neural networks.

A mutation that gives people rock-bottom cholesterol levels has led geneticists to what could be the next blockbuster heart drug.

An ambitious plan to slash greenhouse-gas emissions must clear some high technical and economic hurdles.

Kristoffer Famm and colleagues unveil a multidisciplinary initiative to develop medicines that use electrical impulses to modulate the body's neural circuits.

Sidekick status does Alfred Russel Wallace an injustice. He was a visionary scientist in his own right, a daring explorer and a passionate socialist, argues Andrew Berry.

David Quammen re-enters the 'Milky Way of land masses' evoked by Alfred Russel Wallace's masterpiece of biogeography.

Lucy Odling-Smee scopes out the new waterfront abode of Frank Oppenheimer's San Francisco museum.

Genevieve Dion works at textile engineering's cutting edge at Drexel University in Philadelphia, Pennsylvania. Ahead of the Smart Fabrics conference in San Francisco, California, she talks about knitting robots, permanently pleating silk and charging mobile phones from shirts.

The philosopher Albert Camus once said, “Life is the sum of all your choices”. Work using an innovative experimental design in humans and rats shows that many of the errors in those choices come from the senses, not from cognition.

Using a hexagonal array of helical waveguides, physicists have observed robust optical waves that move in one direction, bypassing obstacles and imperfections exactly as predicted by the theory of topological insulators. See Letter p.196

Anxiety does not arise from a single neural circuit. An interplay between neighbouring, yet opposing, circuits produces anxiety, and outputs from these circuits regulate specific anxiety responses. See Letters p.219 & p.224

Genome sequencing of cells plucked from marine sediments reveals metabolic details for two abundant lineages of Archaea. These microorganisms may play a key part in breaking down protein buried deep inside Earth. See Letter p.215

Telomerase synthesizes DNA sequences that protect the integrity of chromosome ends. A model for how the components of this enzyme complex co-assemble offers insight into its structure and function. See Article p.187

Saturn's atmosphere bears a latent image of its icy rings, implying that electrically charged bits of water ice are being transported along magnetic-field lines of force from sources in the ring plane to the upper atmosphere. See Letter p.193

The authors show that photosynthetically derived glucose drives target-of-rapamycin signalling, resulting in transcriptional reprogramming of genes involved in cell cycle regulation.

The long-awaited structure of a telomerase holoenzyme, from Tetrahymena, has been obtained by electron microscopy; affinity labelling of subunits and modelling with NMR and crystal structures of various components allowed the identification of the catalytic core and subunit interactions, and the functional role of the subunits in telomerase processivity was enabled by performing the first reconstitution of the holoenzyme in vitro.

A pattern of features is detected, superposed on Saturn’s low-latitude infrared glow, that implies the transfer of charged species derived from water (ring ‘rain’) from the ring plane to the ionosphere, ultimately leading to the global modulation of upper atmospheric chemistry.

An experimental realization of a photonic topological insulator is reported that consists of helical waveguides arranged in a honeycomb lattice; the helicity provides a symmetry-breaking effect, leading to optical states that are topologically protected against scattering by disorder.

By use of a hierarchical Bayesian analysis of instrumental and proxy temperature records, early twenty-first-century summers at high northern latitudes are shown to have been warmer than any since 1400.

Topographic analyses and numerical modelling of canyon formation across the Hawaiian island of Kaua‘i show that rivers erode into bedrock more efficiently where precipitation rates are higher.

Analysis of an Early Jurassic dinosaur bone bed reveals the rapid early growth stages of sauropodomorph embryos as well as the earliest evidence of in situ organic remains from a terrestrial vertebrate.

Miscellaneous crenarchaeotal group (MCG) and marine benthic group-D (MBG-D) are among the most numerous archaea in sea-floor sediments; single-cell genomics reveals that these archaea belong to new branches of the archaeal tree and probably have a role in protein remineralization in anoxic marine sediments.

Different subregions of the bed nucleus of the stria terminalis are shown to increase and decrease anxiety in mice, and distinct neural projections arising from a single coordinating brain region modulate different anxiety features.

Examination of the bed nucleus of the stria terminalis projections to the ventral tegmental area shows that glutamatergic and GABAergic projections have opposing effects on reward and anxiety.

In vivo ‘cellular barcoding’ shows that early haematopoietic progenitors are heterogeneous in the cell types that they produce, and this is partly due to an ‘imprinting’ of fate in progenitors, including for a separate dendritic cell lineage.

Salmonella effector proteins trigger host innate immunity through the activation of small Rho GTPases, which, in turn, is sensed by the NOD1/2 signalling pathway.

Succinate is identified as a metabolite in innate immune signalling, which leads to enhanced interleukin-1β production during inflammation.

The crystal structure of the FimD usher traversed by the tip complex of a type 1 pilus demonstrates the mechanism by which pilus subunits are assembled and translocated during pilus elongation.

Several X-ray crystal structures of an H⁺-driven multidrug and toxic compound extrusion (MATE) transporter from Pyrococcus furiosus are presented, whose complex structure with macrocyclic peptides may help facilitate the discovery of efficient inhibitors of MATE transporters.

Advances in cell culture media mean that scientists increasingly know what has gone into the mix, and cells are enjoying a more natural environment — even in the lab.

Involving members of the public can help science projects — but researchers should consider what they want to achieve.

US budget woes put non-tenured researchers at risk.

Proposed law aims to smooth researcher mobility across the European Union.

Video platform enables global real-time discussion.

A sound investment.