Volume 456 Issue 7222, 4 December 2008

An online row highlights the need for Chinese universities to fix their hiring policies.

Europe is rightly pioneering the systematic appliance of science in space to societal needs.

A lack of laboratory reagents is taking its toll on researchers.

Top universities shun Joint Technology Initiatives.

Tumour treatments may need a rethink.

Exotic superconductors promise savings.

BRCA1 patent decision may be ignored in clinics.

Scandals prompt formation of misconduct body.

Oversimplifying the effect of the space race on US science funding could lead scientists down the wrong path, says David Goldston.

The current crisis in worldwide food prices reinforces the need for more productive agriculture. Emma Marris meets five ambitious scientists determined to stop the world from going hungry.

The time is right to push global learning beyond primary-school level, says Joel E. Cohen. The benefits could include a dramatically smaller increase in world population by 2050.

More deadly than the First World War, the global outbreak of influenza in 1918 terrified populations and tested governments. But would we fare any better today, asks Michael Sargent?

The Columbia–Princeton Electronic Music Center in New York was the first institution of its kind in the United States for experimenters seeking new technology-based sounds. Fifty years after its founding, director of research Doug Repetto explains how electronic music has evolved and how the role of academic music centres is changing.

Poland's oldest university museum celebrates the Sun-centred ideas of Copernicus and the history of the nation itself, explains Alison Abbott.

Mathematical models can reveal how prosocial human behaviour — and even social intelligence and language — have evolved, argues Martin A. Nowak.

Can every tumour cell propagate human cancers or is this property exclusive to an elite subset? Findings are divided. The latest set shows that — depending on circumstances — both perspectives can be correct.

Electric fields offer an innovative means of controlling condensed-matter systems. The approach has been applied to nanoscale oxide interfaces, for studying the physics of two-dimensional superconductors.

Early middle age is a difficult time, not least for male fruitflies when sperm production falls. The unexpected reason for this decline seems to be that, as tissues age, maintaining functional stem cells becomes difficult.

The mammalian egg coat participates in fertilization and prevents more than one sperm from entering the egg. Structural data pinpoint a region common to egg-coat proteins that might mediate these functions.

Light reflected off a dust cloud in the vicinity of the relic of Tycho Brahe's supernova, whose light first swept past Earth more than four centuries ago, literally sheds light on the nature of this cosmic explosion.

The workhorse of cell biology, yeast, is a surprisingly cooperative organism. It uses an unusual means of identifying partners — a 'green-beard gene', which encodes a tag that must match among cooperating cells.

Memories are encoded by efficient signalling between neurons. The myosin V proteins help this process by shuttling receptors and membranes to make synaptic junctions better detectors of incoming signals.

Cancer stem cells in human tumours have been defined as cells that are tumourigenic and self-renew when transplanted into immunocompromised mice. It has been shown in a number of tumour types that such cancer stem cells exist at relatively low frequencies. This paper now shows that in human melanomas at least, there is a high proportion of tumourigenic cells when the conditions for such transplanation experiments are modified, casting doubt on the generality of the cancer stem cell model.

Asymmetric division of adult stem cells generates one self-renewing stem cell and one differentiating cell, thereby maintaining tissue homeostasis. This paper shows that changes in stem cell orientation within the niche during ageing contribute to the decline in spermatogenesis in Drosophila male germ line.

It is shown that a mitochondrial protein, mitofusin 2, is enriched at the mitochondrial–endoplasmic reticulum interface and mediates tethering of both organelles. Ablation of mitofusin 2 results in disruption of endoplasmic reticulum morphology and loss of calcium transfer between the two organelles. Thus, mitofusin-2 mediates tethering mitochondria to the endoplasmic reticulum.

This paper identifies a gene, kintoun (ktu), which is important for dynein arm formation resulting in the formation of motile cilia. It is conserved from ciliated unicellular organisms to higher mammals. Mutations in the homologous gene of two human primary ciliary dyskinesia families are also identified.

This study reports an optical spectrum of Tycho Brahe's supernova near maximum brightness, obtained from a scattered-light echo more than four centuries after the direct light of the explosion swept past Earth. It is found that SN 1572 belongs to the majority class of normal type Ia supernovae.

When seen in ultraviolet light, Venus has contrast features that arise from the non-uniform distribution of unknown absorbers within the sulphuric acid clouds. This paper reports multi-wavelength imaging that reveals that the dark low latitudes are dominated by convective mixing that brings the ultraviolet absorbers up from depth. The bright and uniform mid-latitude clouds reside in the 'cold collar', which suppresses vertical mixing. In low and middle latitudes, the visible cloud top is located at a constant altitude of 72 ± 1 km in both the ultraviolet dark and bright regions, indicating that the brightness variations result from compositional differences caused by the colder environment.

It has been a goal in applied physics to construct devices in which superconductivity can be switched on and off with an electric field. Recently, it was shown that the conducting interface between LaAlO₃ and SrTiO₃ (both in bulk form are insulators) can produce a two-dimensional superconducting condensate. This paper now uses the electric field effect, which tunes the charge carrier density, to explore the phase diagram of the system.

A late-autumn shoulder is consistently observed in the seasonal cycles of atmospheric methane at high latitude sites, but the sources responsible remain uncertain. This study reports methane flux measurements from a high Arctic setting during the onset of soil freezing. The integral of the emissions during this freeze-in period amount to approximately the same amount of methane emitted during the entire summer season. It is found that the observed early winter emission burst improves the agreement between the simulated seasonal cycle and atmospheric data from latitudes north of 60°N. The results suggest that permafrost associated freeze-in bursts of methane emissions from tundra regions could be an important component of the seasonal distribution of methane emissions from high latitudes.

In March 2005 the Sunda megathrust earthquake, with a moment magnitude of 8.6, occurred. Concern was then focused further south on the Mentawai area, where large earthquakes had occurred in 1797 (magnitude 8.8) and 1833 (magnitude 9.0). On 12 September 2007, a magnitude 8.4 earthquake occurred, followed by a magnitude 7.9 earthquake 12 hours later. This paper shows that these earthquakes ruptured only a fraction of the area ruptured in 1833 and conclude that the stress state on the portion of the Sunda megathrust that ruptured in 1797 and 1833 was probably not adequate for the development of a single major large rupture in 2007, meaning that the potential for a large megathrust event in the Mentawai area thus remains high.

Early hypotheses suggested that the digits of tetrapods (land vertebrates) were homologues of fin radials, but this idea fell out of favour on the basis of developmental studies and also on the fin of Panderichthys, a fish closely related to land vertebrates, which appeared to lack distal digit-like fin radials. A new CT study of a classic specimen of Panderichthys shows that the old interpretation was in error. Panderichthys did indeed have digit-like radials: nothing stands in the way of the era of fish fingers.

Brain–machine interfaces are a promising approach for treating spinal cord injury-caused paralysis by rerouting control signals from the brain directly to the muscles. This paper demonstrates that monkeys can directly control stimulation of muscles using the activity of neurons in motor cortex, restoring goal-directed movement to a transiently paralysed arm. In addition, monkeys learned to use these artificial connections so that single neurons previously not associated with the movement could be used to control functional stimulation.

A role for Sox18 transcription factor has been suggested by lymphatic dysfunction in the human syndrome hypotrichosis-lymphedema-telangiectasia (HLT), which is caused by mutations in Sox18. This paper shows that Sox18 directly activates Prox1 transcription. Sox18-null embryos show a complete absence of Prox1-positive lymphatic endothelial cells emanating from the cardinal vein.

Shiga toxigenic Escherichia coli causes severe gastrointestinal disease, which is in part mediated by subtilase cytotoxin. The B subunit of this toxin is now shown to have high affinity to glycans containing N-glycolylneuraminic acid, a saccharide that is not synthesized by humans. Instead it is ingested by dietary intake of red meat and dairy products and subsequently incorporated into intestinal and kidney tissue.

Species-specific recognition between the egg extracellular matrix (zona pellucida) and sperm is the first step of mammalian fertilization. This paper reports the 2.3 Å resolution structure of the 'zona pellucida filament' of the egg, which act as sperm receptors. The structure supports the presence of ZP–N repeats within the amino-terminal region of ZP2 and other vertebrate zona pellucida/vitelline proteins, and has implications for egg coat architecture and the post-fertilization block to polyspermy and speciation.

Endolysosomal proteolytric cleavage is shown to be required for TLR9 activation by CpG

Tamoxifen is commonly used for breast cancer therapy. This paper shows that the transcriptional repression of the ERBB2 oncogene by tamoxifen in breast cancer cells is affected by an antagonistic interaction between the transcriptional regulators PAX2 and AIB-1. This affects the ability of tamoxifen to inhibit cancer cell proliferation. The relative levels of PAX2 and AIP1 in breast cancer patients treated with tamoxifen correlates with relapse-free survival.

Suppressing the homologous recombination of repetitive DNA sequences is important for maintaining genome stability, and packaging of repeat DNA into silent chromatin was generally thought to protect it from recombination. Yeast ribosomal DNA (rDNA) repetitive sequences are shown to associate with the nuclear periphery via inner nuclear membrane proteins, and this tethering is required for rDNA stability. Sir2-dependent silencing is not sufficient to inhibit rDNA recombination.

Political upheaval opens up an avenue for a scientific career.

Major donation fuels big plans for cancer-research institute in Oregon.

Is my career taking over my life, one baboon at a time?

There's no time like the present.

An extended research season finds a surprising burst of greenhouse gas.