Contents: (Small 14/2012)

Biomimetic MineralizationWhen 3D peptide amphiphile assemblies with fl at and cylindrical morphologies are used as templates for mineralization, the nanoscale architecture is found to play a signifi cant role in orienting hydroxyapatite in a bone-like fashion.Cylindrical nanostructures facilitate mineral orientation parallel to the long axis of the 1D assembly while fl atter, ribbon-like architectures nucleate randomly oriented mineral.Macroscopically aligned constructs of the cylindrical nanostructures further demonstrate the ability to orient hydroxyapatite across length scales.This work by S. I. Stupp and co-workers on page 2195 emphasizes the importance of template morphology. Logic GatesThe cover picture illustrates how the hairpin-structured molecular beacon probe interacts with DNA input and generates a high fl uorescence signal through a sequencespecifi c hybridization, as demonstrated by H. G. Park and co-workers on page 2203.By employing this molecular beacon probe as a basic work unit and rationally designing a series of DNA inputs, a new universal platform technology for molecular logic gates is demonstrated, which achieves not only a complete set of two-input logic gates, but also gate wiring in multilevel circuits and the reversible modulation of logic gates.This work holds great promise for applications in molecular computing and bioelectronics. Planar Micro-OpticsNature provides ten different anatomical structures of compound eyes for arthropod vision.The cover image presents the direct visualization of light propagation inside natural compound eyes.Despite being an inspiration to engineering, none of these vision schemes is well understood.The method presented by K.-H.Jeong and coworkers on page 2169 provides a novel approach to emulating the optical schemes and functions of two representative types of simple apposition and refl ecting superposition.