Volume 511 Issue 7509, 17 July 2014

A redoubling of efforts should swiftly eradicate polio from its last strongholds.

Researchers investigating different farming practices should not have to pick sides.

A Facebook study that manipulated news feeds was not definitively unethical and offered valuable insight into social behaviour, says Michelle Meyer.

The week in science: Smallpox found in fridge; HIV-rebound dashes hope of ‘cure’; and scandal over faked peer review.

UK government considers eight proposals for up to six research centres.

Forum on deadly natural phenomena discusses use of simulation and hazard-mapping technologies.

Other independent biomedical research institutions have turned to private benefactors.

Particle-physics lab sets up fund for ‘extras’ as other big institutes mull similar move.

After two decades and more than half a billion dollars, LIGO, the world's largest gravitational-wave observatory, is on the verge of a detection. Maybe.

Gastric-bypass surgery can curb obesity as well as diabetes and a slew of other problems. Researchers are now trying to find out how it works.

Boosting basic medical services and routine immunizations — not travel vaccinations — is the key to ending polio worldwide, says Zulfiqar Ahmed Bhutta.

Clinicians and neuroscientists must work together to understand and improve psychological treatments, urge Emily A. Holmes, Michelle G. Craske and Ann M. Graybiel.

Tilli Tansey ponders a turbulent history of vaccine research in Nazi-occupied Europe.

The machine that houses the world's largest laser, and which stands in for the starship Enterprise's warp core in the film Star Trek Into Darkness, has compressed diamond to the density of lead. See Letter p.330

Decreases in bird numbers are most rapid in areas that are most heavily polluted with neonicotinoids, suggesting that the environmental damage inflicted by these insecticides may be much broader than previously thought. See Letter p.341

Whether supernovae create most of the dust in the cosmos is a controversial question. Observations of a distant supernova have revealed signs of freshly formed dust, but the properties of the dust are unexpected. See Letter p.326

The protein Npas4 dampens activated excitatory brain circuits by recruiting inhibitory signals to excitatory neurons. It emerges that this protein has the opposite role in some inhibitory neurons, promoting their activity.

Cell membranes are covered with sugar-conjugated proteins. New findings suggest that the physical properties of this coating, which is more pronounced in cancer cells, regulate cell survival during tumour spread. See Article p.319

Superelasticity — a form of elasticity that involves a phase transition — has been observed for the first time in a pure organic crystal. The material could find applications in microfluidics.

Production of blood stem cells from reprogrammed adult cells is notoriously difficult. It emerges that a supportive microenvironment may be crucial for their efficient generation. See Article p.312

Data on Vesta’s surface material provided by the Dawn probe and impacts modelling reveals that Vesta’s crust–mantle boundary must be deeper than 80 kilometres below the surface.

Traits responsible for recent niche divergence between sympatric threespine stickleback species are subjected to forward genetic analysis; additive variation at several loci across the genome accounts for most of the genetic basis of ecological divergence, with a further role for epistatic interactions that disadvantage hybrids.

This study describes the conversion of human fetal and adult vascular endothelial cells into engraftable haematopoietic progenitors by transduction with some transcription factors and then culture on a vascular niche feeder layer; the haematopoietic progenitors may be useful for the generation of engraftable healthy and long-lasting haematopoietic cells for treatment of inherited and acquired blood disorders.

Metastatic cancer cells are shown to have a tendency towards forming a bulky glycocalyx owing to the production of large glycoproteins, and this cancer-associated glycocalyx has a mechanical effect on the spatial organization of integrins — by funnelling integrins into adhesions, integrin clustering and signalling is promoted, which leads to enhanced cell survival and proliferation.

The formation of dust in the dense circumstellar medium of the bright supernova 2010jl is at first rapid and produces very large grains, which resist destruction, whereas later the dust production rate increases, meaning its source is ejecta; this links early and late dust mass evolution in supernovae with dense circumstellar media.

New laboratory techniques for applying enormous pressures allow diamond to be compressed to 50 million atmospheres, providing insight into the interiors of planets and theoretical implications.

MgCl₂ is shown to be a cheap and non-toxic replacement for the costly and environmentally unfriendly salt CdCl₂ that has long been used as the ‘activation’ step in the production of cadmium telluride solar cells.

Magnetotelluric data from the state of Washington, USA, are used to image the fluid–melt phase of volcanic subduction in Mt Rainier, revealing fluid release at or near the top of the slab, and its migration into the overlying mantle.

The water concentrations of imidacloprid, a neonicotinoid pesticide, correlate with declines in farmland bird populations in the Netherlands.

Whole-genome sequencing is used to identify genetic alterations in patients with severe intellectual disability for whom all other tests, including array and exome sequencing, returned negative results; de novo single-nucleotide and copy number variations affecting the coding region seem to be a major cause of this disorder.

A rodent study using optogenetics to induce long-term potentiation and long-term depression provides a causal link between synaptic plasticity and memory.

The loss of limbal stem cells (LSCs) due to injury or disease is one of the leading causes of blindness; here, the ABCB5 protein is identified as a marker of LSCs in mouse and human eye, and shown to be functionally required for LSC maintenance, corneal development and repair.

p63 and PAX6 act to specify limbal stem or progenitor cells (LSCs), and WNT7A controls corneal epithelium differentiation through PAX6; loss of WNT7A or PAX6 induces LSCs into epithelium, and transduction of PAX6 in skin epithelial stem cells converts them to LSC-like cells and transplantation in a rabbit corneal injury model can replenish corneal epithelial cells and repair damaged corneal surface.

BRCA2, the breast cancer susceptibility gene factor, interacts with TREX-2, a protein complex involved in the biogenesis and export of messenger ribonucleoprotein, to process DNA–RNA hybrid structures called R-loops that can trigger genome instability; these may be a central cause of the stress occurring in early cancer cells that drives oncogenesis.

RNA molecules can perform multiple functions, which can be driven by different conformational states; here, the crystal structure of the transfer-RNA-like structure of the turnip yellow mosaic virus is solved, providing insight into the structural basis of RNA multifunctionality.

Researchers working at the interface of disciplines can pursue insights without sacrificing career progress.

Computer scientist models global ecology.

Out in the cold.