Reviews & Analysis

An approach integrating different data sets has been used to map out seismic-velocity ratios in the crust of western North America. High inferred quartz content correlates with tectonic deformation zones. See Letter p.353

Spherical micelles can aggregate into highly organized structures. New micelle arrangements mimic known atomic crystals, both periodic and aperiodic, and provide evidence for a material with 18-fold rotational symmetry.

Initiation of the great 2010 Chile earthquake occurred within the rupture zone of the 1835 event experienced by Charles Darwin. However, the peak fault slip was to the north of the epicentre — not where it was expected to occur.

To understand the brain, the thousands of synaptic connections made by each of billions of neurons should be mapped and related to neuronal function. First steps towards this formidable goal are now reported. See Articles p.177 & p.183

In the effort to demonstrate quantum behaviour in the motion of macroscopic mechanical objects, strong coupling between the objects and an electromagnetic oscillator is advantageous. Such coupling has now been achieved. See Letter p.204

Using a microfluidic device, tiny polymeric capsules have been made in which different compounds can be isolated in separate, membrane-bound compartments — a prerequisite for the development of artificial cell aggregates.

The vitamin-A metabolite retinoic acid normally favours immune tolerance in the gut. But in coeliac disease — an intestinal inflammatory disorder due to adverse reactivity to a dietary protein — it may do just the opposite. See Letter p.220

The parasitic infection mucocutaneous leishmaniasis can vary in severity. It emerges that the levels of an RNA virus within the parasite affect both the host's immune response and the parasite's persistence.

The origin of the annelids is buried in distant evolutionary time. A molecular phylogeny resolves their deep family interrelationships and provides a picture of their 'urannelid' ancestor. See Letter p.95

A novel explanation for the long-term temperature record in Antarctic ice cores invokes local solar radiation as the driving agent. This proposal will prompt palaeoclimate scientists to pause and to go back to basics. See Letter p.91

Induced pluripotent stem cells have great therapeutic potential. But genomic and epigenomic analyses of these cells generated using current technology reveal abnormalities that may affect their safe use. See Articles p.58, p.63 & p.68

Summer sea-ice extent in the Arctic has decreased greatly during recent decades. Simulations of twenty-first-century climate suggest that the ice can recover from artificially imposed ice-free summer conditions within a couple of years.

Theory suggests that the accuracy of a decision often increases with the number of decision makers, a phenomenon exploited by betting agents, Internet search engines and stock markets. Fish also use this 'wisdom of the crowd' effect.

The protein Sae2 mediates the repair of double-strand breaks in DNA. It emerges that Sae2 activity is controlled by both its modification with acetyl groups and its degradation by the process of autophagy. See Article p.74

The idea of using ultracold atoms to simulate the behaviour of electrons in new kinds of quantum systems — from topological insulators to exotic superfluids and superconductors — is a step closer to becoming a reality. See Letter p.83

Protein folding is a high-stakes process, with cell dysfunction and death being the unforgiving penalties for failure. Work in bacteria hints that organisms manage this process beyond the boundaries of the cytoplasm — and even the cell.

In 2–3% of cancers, a single genetic event may have led to hundreds of genomic rearrangements confined to just one or a few chromosomes. This finding challenges the conventional view of how mutations accumulate in oncogenesis.