Contents
Vol 306, Issue 5698
Contents
This Week in Science
Editorial
Editors' Choice
NetWatch
Products & Materials
News of the Week
ScienceScope
Random Samples
News Focus
Letters
Books
Essays on Science and Society
Perspectives
Review
Brevia
- Uridine Addition After MicroRNA-Directed Cleavage
In plants, strings of uridine nucleotides are added to the bits of messenger RNA remaining after cleavage by microRNA, marking them for disposal.
Reports
- Jet and Accretion-Disk Emission Untangled in 3C 273
Much of the high-energy light coming from the region surrounding a black-hole nucleus of a nearby galaxy is from a highly variable jet of plasma.
- Energy Transfer Across a Metal Film Mediated by Surface Plasmon Polaritons
Coupled emissions of light and electrons can transfer energy between molecules more than 100 nanometers apart on either side of a thin silver film.
- Enhancement of Ferroelectricity in Strained BaTiO3 Thin Films
A barium titanate film grown on an appropriately mismatched substrate is strained and therefore especially ferroelectric, providing a new material for memory storage devices.
- Cation Exchange Reactions in Ionic Nanocrystals
The divalent cations in cadmium selenide nanoparticles can be completely and reversibly replaced with monovalent silver cations, providing a route for synthesis of novel materials.
- Hysteretic Adsorption and Desorption of Hydrogen by Nanoporous Metal-Organic Frameworks
Two nickel-organic compounds have small flexible pores, less than 1 nanometer across, that allow high-pressure loading of hydrogen and storage at lower pressures.
- Long-Term Aridity Changes in the Western United States
Tree rings reveal that much of the western United States suffered frequent and severe droughts 700 to 1100 years ago, a time when Earth's climate was relatively warm.
- Biodiversity Effects on Soil Processes Explained by Interspecific Functional Dissimilarity
Leaves decompose faster when diverse soil-dwelling invertebrates with many different functions are present than they do with highly abundant, but fewer, groups.
- Dynamic Instability in a DNA-Segregating Prokaryotic Actin Homolog
A prokaryotic actin homolog polymerizes and depolymerizes as microtubules do in eukaryotes, perhaps helping DNA segregate during bacterial cell division.
- Accumulation of Mn(II) in Deinococcus radiodurans Facilitates Gamma-Radiation Resistance
The very high concentrations of manganese in radiation-resistant bacteria likely mitigate damage due to radiation-induced oxygen species.
- Nicotine Activation of α4* Receptors: Sufficient for Reward, Tolerance, and Sensitization
In mice, one subtype of the acetylcholine receptor is responsible for nicotine addiction.
- MHC Class I Peptides as Chemosensory Signals in the Vomeronasal Organ
In mice, small peptides like those that bind to immune receptors can act as pheromones by activating nasal sensory neurons to regulate behavior.
- Autophagy Defends Cells Against Invading Group A Streptococcus
Ordinary, nonimmune cells can destroy invading bacteria via a degradation system normally used to mobilize cellular components for reuse in times of stress.
- Structural Insights into the Assembly of the Type III Secretion Needle Complex
Electron cryomicroscopy reveals several configurations of the needle-like structure used by bacteria for injection of virulence factors into host cells, suggesting how the needle opens.
- Tracking SNARE Complex Formation in Live Endocrine Cells
A fluorescent tagged protein allows visualization of the early stages of calcium-dependent secretion from living cells.
- A Link Between mRNA Turnover and RNA Interference in Arabidopsis
During RNAi-triggered destruction of RNAs, the RNAi machinery recognizes its aberrant RNA target by the absence of the usual cap at its 5'?end.
Technical Comments
