Strain-induced damage typically limits the bending radius of electronic circuits to a few millimetres. The development of very thin organic transistors and electronic circuit designs that show a bending radius down to 100 [mu]m will enable novel applications with unconventional form factors.

Cover design by David Shand.

Article by Tsuyoshi Sekitani et al.

DNA-functionalized, anisotropic nanostructures, such as nanorods and triangular nanoprisms, are shown to assemble by means of DNA hybridization into colloidal crystal structures. The crystallization parameters of these nanostructures, and hence the dimensionality and symmetry of the resultant superlattice, are strongly influenced by particle shape.

Cover design by David Shand.

Letter by Jones et al.

Actin filaments are a principal component of the cell cytoskeleton. Using micropatterning methods, physical influences on the growth of highly ordered actin structures are investigated. The spatial organization of actin nucleation sites (bright ring on the image) is discovered to play an important role in establishing the architecture of actin networks.

Cover design by David Shand.

Letter by Reymann et al.

Biochemical assays that use magnetic beads are at present in frequent use. Colour-barcoded magnetic microparticles have now been created without using multiple pigmentations. The coding capacity far exceeds that of alternative spectral encoding systems and is demonstrated in a practical bioassay for DNA detection and identification.

Cover design by David Shand.

Letter by Lee et al.

Fibres are typically used as passive devices, whether in fibre-optical cables used in telecommunciations or as yarns for clothing. The demonstration of polymer-based piezoelectric fibres that can be drawn to tens of metres in length, and whose acoustic response can be actively controlled, suggests possible applications in, for example, medical imaging or acoustic sensing.

Cover design by David Shand.

Image credit: Research Laboratory of Electronics at MIT / Greg Hren Photography.

Letter by Egusa et al.

Peptide-based molecules that self-assemble into lamellar plaques with fibrous texture on heating, subsequently break on cooling to form long-range aligned bundles of nanofibres. This thermal route to monodomain gels is compatible for living cells and allows the formation of noodle-like viscoelastic strings of any length.

Cover design by David Shand.

Article by Zhang et al.

Electronics that are capable of intimate integration with the surfaces of biological tissues create opportunities for improving animal/machine interfaces. A bio-interfaced system of ultrathin electronics supported by bioresorbable silk-fibroin substrates is now presented. Mounting such devices on tissue and then allowing the silk to dissolve initiates a conformal wrapping process that is driven by capillary forces.

Cover design by David Shand.

Article by Dae-Hyeong Kim and Jonathan Viventi et al.

Despite having many similarities with graphene, single-layer boron nitride has a very large bandgap. Now, single-layer hybrids consisting of a blend of domains of boron nitride and graphene have been synthesized. By varying the percentage of boron nitride it is possible to tune the electronic properties, which is a very promising development for potential devices.

Cover design by David Shand.

Article by Ci et al.

As a liquid approaches its glass transition its dynamics slow down and simultaneously the material becomes more heterogeneous. A static structural heterogeneity, now shown to be widely present in glass-forming liquids, is suggested to be the origin of this dynamic heterogeneity that links structural parameters to the glass transition.

Image courtesy of Takeshi Kawasaki and Hajime Tanaka.

Article by Tanaka et al.

Photonic nanostructures offer new ways of light-matter interaction. Examples of these nanostructures include microrod arrays that show efficient light absorption, but also plasmonic devices whose light-concentration capability can be used for enhanced solar cells.

Image courtesy of M. D. Kelzenberg.

Letter by Kelzenberg et al.

Biocompatible, lithographically defined, ferromagnetic microdiscs that have a spin-vortex ground state oscillate when activated by an alternating magnetic field. This oscillation compromises the integrity of the cell membrane and initiates programmed cell death in ~90% of cancer cells in vitro, even with a low-frequency field applied for only ten minutes.

Cover design by David Shand

Article by Kim et al.

Lithium-ion batteries have contributed to the commercial success of portable electronics, and should affect higher-volume applications such as plug-in hybrid electric vehicles. A fluorosulphate insertion positive electrode showing promising electrochemical performance is now reported.

Cover design by David Shand

Article by Recham et al.