Volume 465 Issue 7299, 10 June 2010

Biomedical research continues to use many more male subjects than females in both animal studies and human clinical trials. The unintended effect is to short-change women's health care.

It is in researchers' interests to help funding agencies quantify the economic benefits of their work.

The re-auditing of accounts from the closed Sixth Framework Programme is generating hostility.

The week in science.

Reports throw unsubstantiated suspicion on scientific advice given to the World Health Organization.

MIT's Subra Suresh poised to take top job.

As President Lula prepares to leave office, researchers expect that innovation will invigorate the economy.

Time is running out for vanishing vaquitas.

Natural climate swings have had a major role in eroding Alpine ice.

Tuition fees have risen, but public universities still face a shortfall, and students are feeling the squeeze.

With chytrid fungus rapidly spreading around the world, researchers are testing an extreme approach to saving endangered amphibian populations. Naomi Lubick reports from a rescue site.

Spending on science is one of the best ways to generate jobs and economic growth, say research advocates. But as Colin Macilwain reports, the evidence behind such claims is patchy.

As climate scientists battle climate sceptics, they should note that we have been here before, say Naomi Oreskes and Erik M. Conway. History holds lessons for how researchers can get their message across.

Gender inequalities in biomedical research are undermining patient care. In the first of three related pieces, Alison M. Kim, Candace M. Tingen and Teresa K. Woodruff call on journals, funding agencies and researchers to give women parity with men, in studies and in the clinic.

Clinical trials routinely exclude expectant mothers. This is unethical and unscientific, and regulators must mandate change, says Françoise Baylis, in the second of three related pieces on gender bias in biomedicine.

Many researchers avoid using female animals. Stringent measures should consign this prejudice to the past, argue Irving Zucker and Annaliese Beery, in the third piece of three on gender bias in biomedicine.

The most extensive evaluation to date finds that the European Union Emissions Trading Scheme is robust and successfully cut the region's emissions in its first three years, explains Michael Grubb.

A growing underground art movement combines mathematics, technology, stalks and whimsy. Richard Taylor looks forward to a bumper batch of intricate crop patterns this summer.

The steroid hormones oestrogen and progesterone have a role in sickness and in health. In breast tissue, both roles probably work through a single mechanism: controlling the number and activity of mammary stem cells.

The chaotic motion of light rays gives microlasers surprising emission properties, enhancing quantum tunnelling by many orders of magnitude and producing highly directional output beams.

To form new blood vessels, the endothelial tip cells of two existing vessels come together by the process of anastomosis. But how do they find each other? Macrophages seem to provide a bridge and mediate their union.

A subtle quantum-interference effect has been used to control the optical response of a single atom confined in a cavity. It could offer a means to develop logic gates for an optical quantum computer.

Analysis of a selected class of neuron in the brains of live animals using functional magnetic resonance imaging (fMRI) opens the door to mapping genetically specified neural circuits.

Simulations show that Saturn's nearby moons, after forming on the outskirts of the planet's main rings, get pushed clear of them. This model reproduces the moons' orbital locations and remarkably low densities.

Here the 2.1 Å crystal structure of human immunodeficiency virus (HIV) Tat protein complexed with the positive transcription elongation factor P-TEFb is reported. This shows that Tat binding changes the structure of P-TEFb, which may suggest opportunities for developing inhibitors that block only the form of P-TEFb used by the virus.

A population of Saturn's small moons orbiting outside the main rings are less than 10⁷ years old, which is inconsistent with the formation timescale for the regular satellites. They may have accreted at the rings' edge, but hitherto it has been impossible to model the accretion process. Here a simulation is reported in which the viscous spreading of Saturn's rings beyond the Roche limit gives rise to the small moons.

Electromagnetically induced transparency enables the transmission of a laser pulse through an optically dense medium to be manipulated using a control beam. Here this technique is scaled down to a single atom, which acts as a quantum-optical transistor with the ability to coherently control the transmission of light through a cavity. This may lead to novel quantum applications, such as dynamic control of the photon statistics of propagating light fields.

When a bubble on a liquid–gas or solid–gas interface ruptures, the general expectation is that the bubble vanishes. Here, it is shown that in many cases interfacial bubbles do not simply vanish when they rupture, but rather create numerous small bubbles via unexpected folding of the ruptured bubble as it retracts. The process may increase the efficiency of rupture-induced aerosol dispersal.

Attosecond (10⁻¹⁸ s) laser pulses make it possible to peer into the inner workings of atoms and molecules on the electronic timescale — phenomena in solids have already been investigated in this way. Here, an attosecond pump–probe experiment is reported that investigates the ionization and dissociation of hydrogen molecules, illustrating that attosecond techniques can also help explore the prompt charge redistribution and charge localization that accompany photoexcitation processes in molecular systems.

It has been proposed that the age of the Earth deduced from lead isotopes reflects loss of lead into space at the time of the Moon's formation rather than partitioning into metallic liquids during core formation. Here it is shown that lead partitioning into liquid iron depends strongly on carbon content and that, given a core carbon content of about 0.2%, there is evidence of strong partitioning of lead into the core throughout the Earth's accretion.

Many large mammals became extinct worldwide at the end of the Pleistocene epoch, around 12,000 years ago. Here, it is shown that smaller mammals, which often provide much more comprehensive fossil records than large mammals, were much less likely to respond to the Pleistocene–Holocene transition by becoming extinct. Instead, diversity and evenness suffered, so that less abundant species became rarer, with more generalist 'weedy' species becoming more common.

Millions of pounds per year are spent on various 'brain-training' programs; however, the efficacy and performance of these training regimes is still unclear. In collaboration with the BBC, a six-week online study of brain training was conducted. Although improvements were observed in the specific tasks used for training, in the authors' view there was no evidence that these improvements transferred to other untrained cognitive tasks.

Staphylococcal superantigens can lead to toxic shock syndrome. They are encoded on pathogenicity islands and with the aid of helper phages can be excised and packaged into highly transmissable phage particles. Here it is shown that a specific, non-essential helper phage protein is responsible for derepression of the pathogenicity island, thereby providing the mechanism for the first step of its mobilization.

Proper functioning of the brain requires a balance between the formation of excitatory and inhibitory synapses, but how this is achieved during development is unclear. Here FGF22 and FGF7, two fibroblast growth factor cell–cell signalling molecules, are shown to promote the formation of excitatory and inhibitory synapses, respectively, through their effect on epilepsy in mice. These findings should inform other neurological and psychiatric disorders involving defects in synapse formation.

Blood oxygenation level-dependent (BOLD) signals are the basis for much of the work on which regions of the human brain are active during particular tasks or behaviours, but there is controversy over their source and interpretation. Here a combination of optogenetics and BOLD signal monitoring shows that specific excitatory neurons within a mixed population are sufficient to produce positive BOLD signals, and could be used to map connections.

Using a mouse model of Mycobacterium avium infection, it is shown here that interferon-γ regulates the proliferation of primitive haematopoietic cells during chronic infection.

The ovarian hormones oestrogen and progesterone increase breast cancer risk but the cellular mechanisms are unclear. Here it is shown that the size of the mammary stem cell pool in mice is regulated by steroid hormone signalling, although these cells lack the receptors for oestrogen and progesterone. The augmented pool could lead to clonal expansion of a mutated cell, possibly accounting for the increased incidence of breast cancer associated with pregnancy.

Reproductive history influences breast cancer risk but the cellular mechanisms are unclear. Here it is shown that ovarian hormones regulate the size of the mammary stem cell pool in mice. The size of this pool increases when progesterone levels increase during the reproductive cycle. Progesterone probably regulates stem cell numbers through a paracrine mechanism involving induction of RANKL and Wnt in luminal cells.

The generation of induced pluripotent stem cells (iPSCs) from patients with defined genetic disorders promises to help the basic understanding of complex diseases and the development of therapeutics. Here iPSCs have been generated from patients with LEOPARD syndrome, a developmental disorder with pleiomorphic effects on several tissues and organs. The iPSCs are characterized and the phenotype of cardiomyocytes derived from these cells is investigated.

Down's syndrome is caused by trisomy of chromosome 21, and it is known that the growth of certain tumours is reduced in this genetic disorder. Using a mouse model of Down's syndrome, several individual genes on chromosome 21 are now being proposed to mediate the effect on tumour growth and angiogenesis.

The association of microRNAs with Argonaute proteins (AGOs) yields complexes regulating gene expression. Although bacterial and archaeal miRNAs show no sequence preference at their 5′ ends, eukaryotic miRNAs tend to have a 5′ U or A. Here the structure of the human AGO2 MID domain complexed with ribonucleotide monophosphates is solved, revealing specific interaction of UMP and AMP with a loop that discriminates against CMP or GMP, and explaining the observed preference.

Proteins in cell membranes are notoriously hard to crystallize, but new techniques give scientists the means to map them. Monya Baker scouts out the tools for cracking the structure of membrane proteins.

Research grants offer new posts and routes to independence.

Having a laptop as a lab bench leads to mixed career prospects, says Bryan Howie.

Women are still underrepresented in academic science, and universities are struggling to do something about it. But there are efforts afoot, reports Robin Mejia.

Welcome to the twilight zone.

Plasticity is the capacity of cells or organisms to vary their properties or behaviour when environmental conditions change. Studies over the past few decades have shown that cells are considerably more plastic than had been thought. Uncovering the molecular and cellular mechanisms underlying this plasticity is a dynamic area of biology and biomedicine.