Volume 498 Issue 7454, 20 June 2013

DIY attempts at electrical brain stimulation to improve cognition are to get easier.

The US government gives up its fight to keep age restrictions on the morning-after pill.

The US Supreme Court ruling on gene patents is a welcome boost to efforts to increase the free exchange of scientific information, says Colin Macilwain.

The week in science: Opposition to Japanese ‘NIH’, funding for ExoMars, and endangered status for captive chimps.

IRIS mission aims to scrutinize the layer between the star’s surface and its flickering corona.

First particle containing four quarks is confirmed.

Change to gene patents leaves US biotech in a lather.

Researchers disagree over canine domestication.

Researcher stands by results despite demand for retraction.

Revised data show Soviet Union’s 1970s lunar vehicle outdistanced NASA’s Opportunity — for now.

D-Wave is pioneering a novel way of making quantum computers — but it is also courting controversy.

With earthquake death tolls rising, Ross Stein is building a global risk model to mitigate future disasters.

To change attitudes towards energy scarcity and climate change, focus on transitions and solutions, not danger and loss, says Chris Nelder.

Mark Winston revels in a deep exploration of the honeybee colony and its organization.

Sandra Aamodt evaluates a cautionary account of how brain-scan results could be used and abused.

Biologist who won a Nobel prize for insights into cell structure.

An investigation of droplet freezing in clouds suggests that a minor component of mineral dust in the atmosphere is the main catalyst for this process. Two experts discuss the ramifications of this finding for those investigating cloud-droplet freezing, and for scientists studying atmospheric aerosols. See Letter p.355

A study of wild capuchin monkeys that crack nuts using stone hammers reveals temporal and spatial patterning of the relics of their technological efforts, confirming that such behaviours can be studied from an archaeological perspective.

That HIV cripples the immune system by killing CD4⁺ T cells has long been known. It now emerges that the protein DNA-PK, activated by viral integration into the host-cell genome, is the agent of this death response. See Letter p.376

When biologists unravelled the principles of insect flight, they inspired a generation of engineers to build on their aerodynamic feats. Thanks to a revolution in micro-manufacturing techniques, the first robotic fly now flies.

The configurations of calcium nuclei make them good test cases for studies of nuclear properties. The measurement of the masses of two heavy calcium nuclei provides benchmarks for models of atomic nuclei. See Letter p.346

The discovery that a disordered protein can transmit signals between two binding sites calls into question the idea that communication within proteins requires a specific structural pathway linking such sites. See Letter p.390

The discovery of many new species of hepaciviruses and pegiviruses, which exhibit enormous genetic diversity, in wild rodent and bat populations might help us to understand the origins of the hepatitis C virus.

Realizing holographic video displays is proving far from straightforward, but it is shown here that it may be possible to overcome the limitations of present displays by harnessing the desirable optical manipulation properties of anisotropic leaky-mode spatial light modulators.

This study identifies a deubiquitinase (DUB) that specifically recognises and cleaves linear ubiquitin chains, implicating linear (de)ubiquitination in Wnt signalling and angiogenesis; mutations in gumby cause defects in angiogenesis in mice, and structural and biochemical analysis shows that gumby encodes a linear-ubiquitin-specific DUB.

Cross-species genetic screens reveal that decreased mitogen-activated protein kinase signalling reduces polyglutamine-expanded ataxin 1 levels and toxicity in models of spinocerebellar ataxia type 1.

Cytosolic DNA arising from intracellular bacterial or viral infections induces type I interferon through activation of the DNA sensor cGAS, which catalyses the synthesis of cyclic dinucleotide which in turn activates STING; here the crystal structures of a carboxy-terminal fragment of cGAS alone and in complex with UTP and DNA–ATP–GTP complex are determined.

An observation of a rare merger of two massive submillimetre bright galaxies that is forming stars at an unexpectedly high rate of 2,000 solar masses a year shows that such mergers can indeed form the most massive elliptical galaxies by about redshift 1.5.

The compositions of the 3.7-billion-year-old surface rocks on Mars — as observed by the Spirit rover at Gusev crater — are shown to be consistent with early mixing of oxidized surface material into the uppermost Martian mantle: such oxidation appears to have had less influence on more recent volcanic rocks, which are sampled as Martian meteorites.

The masses of the exotic calcium isotopes ⁵³Ca and ⁵⁴Ca measured by a multi-reflection time-of-flight method confirm predictions of calculations including nuclear three-body interactions.

Molecular dynamics simulations of melting ice have identified the spatial separation of a defect pair into its constituent components as a crucial first step: once this step has been taken, defects can persist and grow, and rapidly turn ice into liquid water.

Feldspar minerals are shown to dominate ice nucleation by mineral dust in clouds containing both liquid water and ice particles, despite feldspar being a minor component of the dust believed to be the main source of ice nuclei.

The complete skeleton of a new avialan dinosaur from the Tiaojishan Formation (Middle–Late Jurassic period) of Liaoning Province, China, is described and included in a comprehensive phylogenetic analysis of basal Paraves.

Two major classes of inhibitory neurons in mouse anterior cingulate cortex, somatostatin and parvalbumin interneurons, form functionally homogeneous populations that are recruited at distinct moments in time and encode unique behavioral variables in a foraging task.

Microbial sequencing of samples obtained from multiple skin sites in healthy human adults shows that core-body and arm sites are dominated by fungal species of the genus Malassezia, whereas foot sites show high fungal diversity, and that skin topography is associated with differential compositions of bacterial and fungal communities.

Two-photon intravital imaging is used here to define the regulation of interstitial neutrophil migration at local sites of cell death upon sterile tissue injury and infection; leukotriene B4 (LTB4) is shown to act between neutrophils as a signal relay molecule that acts to enhance the radius of neutrophil recruitment within the inflamed interstitium, and also to control, in concert with integrin receptors, dense neutrophil clustering for tight wound seal formation.

HIV-1 causes CD4⁺T-cell death through viral integration by stimulation of DNA-dependent protein kinase (DNA-PK), a protein known to act in the p53 damage response pathway for double-stranded DNA breaks, in activated cells.

Cytosolic DNA induces type I interferon via activation of STING; the immediate STING activator is produced by the recently identified DNA sensor cGAS and is shown here to be an unorthodox cyclic dinucleotide harbouring a 2′-5′ linkage between guanosine and adenosine.

In Arabidopsis, RNA-directed DNA methylation is a poorly understood gene silencing pathway in which small interfering RNAs generated by RNA polymerase IV (Pol-IV) target a DNA methyltransferase to its sites of action; here structural and genomic analyses demonstrate that SHH binds chromatin via repressive histone modifications and recruits Pol-IV to enable siRNA production.

Single-molecule FRET is used to examine how an intrinsically disordered protein, the adenovirus E1A oncoprotein, interacts with two different protein partners (the pocket domain of pRb and the TAZ2 domain of CBP/p300); the biophysical behaviour of E1A depends on whether the N-terminal region and/or the CR2 region of E1A is free to interact with potential protein partners or whether they are ‘masked’ (that is, via their absence or a pre-existing interaction with another protein partner).

Meeting attendees can use apps to network and ease logistical hassles.

Sometimes the best outreach happens when lay people stumble over research unawares, says Carolyn Beans.

Contact has been made.