Articles

PTEN is a phosphatase that regulates the phosphatidylinositol-3 kinase signalling pathway and is inactivated in many tumour types. Heet al.show that a mannosidase, α-mannosidase 2C1, can inactivate PTEN in prostate cancer cells, and that PTEN-positive human prostate tumours overexpress α-mannosidase 2C1.

Large-scale separation of single-wall carbon nanotubes into populations of single chirality is a significant challenge in the practical application of nanotubes. Now, using multicolumn gel chromatography, the large-scale separation of 13 different carbon nanotube species is achieved.

The internal textures of columnar-jointed lava flows and intrusions are poorly understood. Mattssonet al. propose a melt-migration model for Icelandic basalt driven by crystallization and volume decrease inside cooling columns, which explains the macroscopic features observed in columnar-jointed basalts.

Sintering is the basis for the production of many metallic and composite materials. Gruppet al. use a new technique to measure the rotation of microscopic copper particles during sintering and find intrinsic rotations to be the dominant movement.

Wave mixing in optical resonators suffers from strong bandwidth constraints, hindering practical implementation. Morichettiet al. report travelling-wave four-wavemixing in coupled ring resonators, which combines the efficiency enhancement of resonant propagation with a wide-band conversion process.

Little is known about the effects of molecular crowding and confinement on biomolecule function. Castronovoet al. investigate the reactions of restriction enzymes with DNA confined in bushy matrices and find that the enzymes enter at the side of the matrix before diffusing two-dimensionally.

Solid gold is most stable as a face-centred cubic structure, and stable colloidal gold with hexagonal close packing has not been produced. Huanget al.prepare square gold sheets with hexagonal close packing that are stable under ambient conditions.

Tropical Pacific hydrology affects the global climate through the strength of the Pacific Walker Circulation. Yanet al. reconstruct variations in the Pacific Walker Circulation in the South China Sea over the last millennium and find that less precipitation fell during warmer and more rainfall during cool periods.

N-methyl-D-aspartate receptors mediate excitatory synaptic transmission, and those containing GluN2D subunits have an unusually long deactivation time. Vance et al. show that the conformational variability of the ligand-binding domain and the structure of the activating ligand influence deactivation time.

Nanometallic optical antennas can concentrate light into a deep-subwavelength volume for sensor and photovoltaic applications. Junet al. demonstrate an optical antenna design that achieves a high level of control over fluorescent emission for a wide range of nanoscale optical spectroscopy applications.

Theory and simulations predict scale-invariant concentration fluctuations during diffusion in liquids, but on Earth, large-scale fluctuations are damped by gravity. Microgravity experiments by Vailatiet al. reveal the scale-invariant nature of diffusion, associated with fractal fronts and long-ranged correlations.

Temperature-controlled regulation of thermal conductivity is difficult to achieve because thermal properties do not change significantly through solid-state phase transitions. Here temperature control of thermal conductivities is demonstrated using liquid–solid phase transitions in a nanoparticle suspension.

Speckle patterns are a manifestation of decoherence and can result from two-particle interference. Here, the authors image atomic speckle for guided matter waves and link this to atom bunching in the second-order correlation function, suggesting potential use in squeezed-atom interferometry applications.

Melting-related phenomena are of fundamental and applied interest, but the melting theory is poorly understood. Levitas and Samani develop an advanced phase-field theory of melting coupled to mechanics that resolves existing contradictions and reveals the features of melting phenomena.

Infrared cameras are used for night vision and in medical diagnostics, but currently only present monochrome images. Krishnaet al. demonstrate a monolithically intergrated plasmonic infrared quantum dot camera as a step towards coloured infrared imaging.

The study of prion diseases has been hampered as there is no method to distinguish newly formed abnormal prion protein conformers. Here, the authors describe a method to study newly formed abnormal prion protein and demonstrate that it is produced within 1 minute of cell exposure to prions.

In vitrostudies have suggested that the ubiquitin ligase, Nedd4-2, regulates several proteins, including the epithelial sodium channel. Here by examining Nedd4-2-deficient mice, the authors demonstrate that Nedd4-2 is essential for epithelial sodium channel regulation, fetal and postnatal lung function and animal survival.

Electron–hole exchange interaction is an intrinsic property of semiconductors, which affects their fine structure. Brovelliet al. demonstrate a nanoengineering-based approach that provides control over the exchange interaction energy at nearly constant emission energy, which cannot be carried out using core-only nanocrystals.

Exosomes released from cells can transfer RNA to recipient cells. In this study, the authors demonstrate that microRNAs in exosomes from T cells can be transferred to antigen-presenting cells during immune synapsis, and that this can alter gene expression, suggesting a new form of cellular communication.

The spatial and temporal scales over which continental breakup occurs by mechanical deformation and magma intrusion remain controversial. Keiret al. quantify anisotropy across the Afar Triple Junction using S-wave splitting from earthquakes to evaluate the strain in a region of continental breakup.