Volume 447 Issue 7144, 31 May 2007

The pharmaceutical industry is struggling to adapt to a harsher political environment.

The United States' domestic security agency has yet to make best use of science and technology.

A meta-analysis of clinical trials for the diabetes drug Avandia has hinted at possible cardiovascular risks; but how clear is the study, and how should meta-analyses be viewed against clinical trials?

A look at the world of Steven Nissen, the cardiologist who raised worries about Vioxx and Avandia.

Infighting over money and equipment plagues US agency.

Universities seek reform of ratings.

Science and technology have not always gone down well at the US Department of Homeland Security. Geoff Brumfiel reports on a retired Navy admiral trying to turn around the troubled research wing.

Incoming president launches superministry for ecology and sustainable development.

Single-celled organisms aren't as basic as they seem.

A handful of pioneers are trying to bring algae-based biofuels back from a near-death experience. Amanda Leigh Haag reports.

How the oceans mix their waters is key to understanding future climate change. Yet scientists have a long way to go to unravel the mysteries of the deep. Quirin Schiermeier reports.

No longer viewed as inert packets of energy, fat cells are two-faced masterminds of metabolism. Kendall Powell weighs up the differences between 'fat' fat cells and thin ones.

Proactive management of trade in endangered wildlife makes more sense than last-minute bans that can themselves increase trading activity, argue Philippe Rivalan and his co-authors.

Two books on the AIDS pandemic in Africa challenge assumptions at the heart of the UN's response.

Meticulous observations of the disk of gas and dust around one young star seem to imply icy, comet-like bodies in the disk's inner regions. Could these be the building-blocks of water-rich planets like Earth?

Restricting dietary intake is one way to promote longevity. The identification of two genes that specifically mediate this effect in worms provides insight into the molecular mechanisms underlying ageing.

Mapping out the strange territory of high-temperature superconductors has proved a challenge. In the latest tour de force, two experiments take big steps forward, in complementary directions, to chart the lie of the land.

That different people differ in their readiness to take risks is an obvious feature of human personality. Theoretical advances now help in making sense of observations of analogous behaviour in animals.

Polaritons — particles comprising both light and matter — can form a coherent state, just as light and matter can individually. This fact has now been exploited to make the first room-temperature polariton laser.

Prions are infectious proteins that are involved in brain-wasting disorders such as mad cow disease. In yeast, specific sequences of amino acids in prions seem to mediate prion propagation and cross-species transmissibility.

Pioneering chemist at the interface with biology.

Increased longevity of diet-restricted Caenorhabditis elegans requires the transcription factor gene skn-1 acting in the ASIs, a pair of neurons in the head. Dietary restriction activates skn-1 in the ASIs, which signals peripheral tissues to increase metabolic activity. These findings demonstrate that increased lifespan in a diet-restricted nematode depends on signalling from central neuronal cells to non-neuronal body tissues, and suggest that the ASIs mediate dietary restriction-induced longevity by an endocrine mechanism.

A Sup35 chimaera that traverses the transmission barrier between two yeast species possesses the critical sequence elements from both. This chimaera is used to show that the influence of environment and mutations on the formation of species-specific strains is driven by selective recognition of either sequence element. Thus, critical aspects of prion conversion are enciphered by subtle differences between small, highly specific recognition elements.

This paper reports spectrally dispersed near-infrared interferometric observations that probe the gas (which dominates the mass and dynamics of the inner disk) and dust within one astronomical unit (Sun–Earth distance) of the young star MWC 480. Water vapour and atomic hydrogen exist interior to the edge of the dust disk. The water vapor is likely produced by the sublimation of migrating icy bodies.

The observation of quantum oscillations in the electrical resistance of YBa₂Cu₃O_6.5, is reported, establishing the existence of a well-defined Fermi surface in the ground state of underdoped copper oxides (once superconductivity is suppressed by a magnetic field). The low oscillation frequency reveals a Fermi surface made of small pockets, in contrast to the large cylinder characteristic of the overdoped regime.

The first spatially resolved measurements of gap formation in a high-T_c superconductor are reported. Over a wide range of doping (0.16 to 0.22), it is found that pairing gaps nucleate in nanoscale regions above T_c. These regions proliferate as the temperature is lowered, resulting in a spatial distribution of gap sizes in the superconducting state.

This paper reports a theoretical design that is a conceptual step forward; spin accumulation is used as the basis of a semiconductor computer circuit rather than flow of spin. A logic gate in this design consists of five magnetic leads on top of a semiconductor layer and is found to perform fast logic operations. The idea is further developed by demonstrating the capability to interconnect a large number of gates.

Tropical cyclones mix the upper layers of the ocean on local scales, and it has been proposed that they are important in ocean mixing at the global scale. This paper reports a calculation of how much tropical cyclones cool the surface of the ocean and the amount of mixing they induce, and finds that they are responsible for significant cooling and vertical mixing of the surface ocean in tropical regions, and that approximately 15 per cent of the total peak ocean heat transport may be associated with tropical cyclone-induced mixing.

The evolution of animal 'personalities' (consistent sets of behaviours shown in a variety of contexts) is shown to be related to an adaptive response to life-history trade-offs.

Decisions on trade-offs between current and future reproduction condition the response of individuals to risky situations.

An experimental test involving two yeast strains validates a model for the formation of new species. The formation of new species might begin with the ecological separation of populations, which then diverge such that hybrids between members of the two populations are less 'fit' than their pure-bred colleagues. This is established with strains of yeast raised on different media, and explores the genetic reasons why hybrids between the two strains are less good at both sexual and asexual reproduction.

Contrary to the assumption that young children must master the logic of number systems before learning symbolic arithmetic, this paper shows that children are capable of solving symbolic addition and subtraction problems with large numbers before they begin arithmetic instruction, provided that only approximate sums and differences must be computed.

How the cell goes about its routine mechanical business of stretching, contracting, and remodelling has implications for understanding excessive airway narrowing in asthma, cell invasion in cancer and vessel constriction in vascular disease. Surprisingly, the cell is an intermediate form of matter, neither solid nor fluid but retaining features of both - that responds to stretch by fluidizing, much as do common pastes, foams, clays, and colloids.

In a synthetic biology approach, GEF domains from Rho GTPases are combined with novel regulatory domains to link cytoskeletal responses to normally unrelated upstream signalling pathways.

The JmjC domain-containing protein SMCX (or JARID1C), implicated in X-linked mental retardation, has histone H3K4 tri-demethylase activity and functions as a transcriptional repressor.

The replication accessory proteins PCNA and RPA are unexpectedly able to stimulate the activity of some of the polymerases that catalyse DNA synthesis. It is speculated that the ability of some polymerases to have their activity enhanced in this way sets up a hierarchy of polymerase utilization at DNA lesions.

Government and industry must do their bit to ensure that universities provide the workforce they want.

A model suggests that reproduction underlies animals' personalities.