Articles in 2012

Malaria can persist at levels that escape detection by standard microscopy, but can be detected by PCR. Okell et al.now show that rates of submicroscopic infection can be predicted using more widely available microscopy data, and are most epidemiologically significant in areas with low malaria transmission.

Species coexistence can be explained by the competition–colonization trade-off theory. Here, Livingston et al. illustrate this theory in a metacommunity experiment using two bacterial strains, finding a negative correlation between diversity and productivity when scaled to full metacommunities.

Abnormal human embryo development is implicated in the embryo arrest observed during in vitrofertilization. Chavez and colleagues perform time-lapse imaging on human embryos and find that chromosomally abnormal embryos exhibit diverse cell cycle parameters that may contribute to arrest.

Polycystic kidney disease family proteins form heteromeric complexes with transient receptor potential channel subunits of the TRPP subfamily. Yu and colleagues find that the polycystic kidney disease protein, PKD1L3, is an ion channel pore-forming subunit in the acid-sensing PKD1L3/TRPP3 complex.

Medium-range structural ordering is expected to exist in supercooled liquids yet direct probes of this are difficult to achieve. Capponi et al.report a new metastable phase of organic molecular glasses exhibiting long-living, highly enhanced orientational order above its glass transition temperature.

Alternative splicing at the Drosophila Down syndrome cell adhesion molecule gene generates 38,016 isoforms, and underlies self-avoidance of growing neurons. Wang et al. identify a structure in the DSCAM mRNA that ensures mutually exclusive splicing and observe expansion of the structure with increasing number of exons during arthropod evolution.

The plasma membrane is thought to comprise a patchwork of ordered and disordered microdomains; however, direct evidence for this in intact cells remains elusive. Using unmixing of fluorescence lifetime decays, Owen et al. show that ordered domains occupy a majority of the plasma membrane surface in living cells.

Mice that cannot produce the hormone Klotho show various aging-related phenotypes. Here, Xie and colleagues reveal that Klotho protects the heart of mice from stress-induced remodelling by inhibiting exocytosis of the TRPC6 ion channel in cardiomyocytes.

PGC-1α regulates mitochondrial biogenesis and adaptive thermogenesis. Cheng and colleagues alter the expression of PGC-1α in primary neuronal cultures and in the adult mouse brain, and find that it regulates dendritic spine formation and maintenance by mediating the synaptogenic actions of BDNF and CREB.

Dysfunctional or aggregated proteins in cells are degraded by autophagy. Wong et al.study aggregates of the protein synphilin-1 and show that ubiquitination alters their dynamic properties, which determines whether the aggregates are degraded via basal or inducible forms of autophagy.

Enzymes are traditionally viewed as being highly specific for their substrates. Tokuriki et al.follow the accumulation of mutations during the laboratory evolution of a phosphotriesterase into an arylesterase, and postulate that many naturally occurring enzymes may not be optimal for their substrates.

Synaptic tagging and capture describes thein vitro protein synthesis-dependent neuronal process where short-lasting forms of response potentiation are stabilised into long-lasting forms. Shires and colleagues find that this phenomenon also occurs in vivoin intact, living animals.

Intense lasers enable scientists to study the behaviour of matter under extreme pressures, but obtaining information about its atomic structure is challenging. In this work, Suggit et al. demonstrate the use of white-light X-ray diffraction to probe the structure of laser-shocked copper on nanosecond timescales.

The potential use of graphene in spintronic devices is limited by its weak spin–orbit coupling. Marchenko et al. report an enhancement of the spin splitting in graphene due to hybridization with gold 5dorbitals, showing a very large Rashba spin–orbit splitting of about 100 meV.

Graphene is a single layer of carbon atoms whose high electron mobility offers potential for cheap, high-speed opto-electronic devices. Docherty et al.show that the terahertz frequency photoconductivity in graphene depends crucially on the type and density of environmental gas adsorbed.

Generation of ultrafast X-rays using lab-based laser sources is promising for numerous spectroscopic and imaging techniques. By generating a long underdense plasma in a solid, Kim et al.show relativistic frequency upshift of a laser pulse to 4.9 nm, caused by reflection from electron nanosheets.

Microbes appear to play an important role in carbon sequestration. Here, the composition of microbial residues in a California grassland with elevated carbon dioxide, warming and nitrogen deposition reveals that warming and nitrogen deposition can both alter the fraction of carbon derived from microbes in soils.

In a nonlinear medium, a pump laser beam generates and amplifies a second beam at a different frequency through stimulated Raman scattering. Sirleto et al.show this effect in silicon nanocrystals in a silicon matrix, with gain greater than four orders of magnitude compared with crystalline silicon.

Graphene and single-walled carbon nanotubes have high electrical conductivities and large specific surface areas. Here, these properties are extended into three dimensions by producing a seamless carbon nanotube graphene hybrid material.

The great increase in flowering angiosperm plants during the Cretaceous began the change towards modern biodiversity. This study shows that rapid angiosperm evolution was possible once the leaf interior transport path length for water became shorter than the leaf interior transport path length for carbon dioxide.