Contents
Vol 304, Issue 5677
Special Issue
SoilsThe Final Frontier
Introduction to special issue
News
Viewpoints
Reviews
Contents
This Week in Science
Editorial
Editors' Choice
NetWatch
Products & Materials
News of the Week
ScienceScope
Random Samples
News Focus
Letters
Books
Policy Forum
Perspectives
Brevia
- Early Precision Compound Machine from Ancient China
Archameides' spirals in ancient Chinese jade rings may have been carved with a simple machine three centuries or more before such machines were invented in the West.
Research Articles
- Fluctuations and Bistabilities on Catalyst Nanoparticles
When large particles of a palladium catalyst are replaced with nanoparticles, fluctuations in the number of CO molecules interacting with the catalyst drive oxidation reaction without hysteresis.
- Phospholipid Metabolism Regulated by a Transcription Factor Sensing Phosphatidic Acid
Opi1p, a transcription factor that represses phospholipid biosynthesis in yeast, is reversibly sequestered on the endoplasmic reticulum depending on the level of phosphatidic acid in the membrane.
Reports
- Femtotesla Magnetic Field Measurement with Magnetoresistive Sensors
A superconducting loop that amplifies the signal from a small magnetic resistor allows detection of minute magnetic fields at much higher temperatures than previously thought possible.
- Ferroelectricity in Ultrathin Perovskite Films
Perovskite films just three unit cells thick continue to store electrical fields, challenging theory.
- Oxoiron(IV) in Chloroperoxidase Compound II Is Basic: Implications for P450 Chemistry
The enzyme chloroperoxidase has an FeIV-OH species that makes it more basic, reducing its redox potential to levels that preserve its polypeptide chains while still allowing it to be a powerful oxidizer.
- Iron Isotope Fractionation and the Oxygen Fugacity of the Mantle
The ratio of iron isotopes in a mineral in Earth's mantle can serve as a new probe to study past variations in oxygen distribution.
- New Zealand Maritime Glaciation: Millennial-Scale Southern Climate Change Since 3.9 Ma
An ocean drill core east of New Zealand shows that glaciers there varied in step with Antarctic climate during the past 370,000 years of a 3.9-million-year record.
- Seawater Sulfur Isotope Fluctuations in the Cretaceous
A 130-million-year isotopic record of seawater sulfate reveals several excursions in Earth's atmospheric oxygen content and also indicates that volcanism and hydrothermal activity decreased about 50 million years ago.
- Soils, Agriculture, and Society in Precontact Hawai`i
Indigenous farmers selected lands with higher phosphorus and cation concentrations for rain-fed cultivation on the younger Hawaiian Islands.
- A Dual Role for Hox Genes in Limb Anterior-Posterior Asymmetry
As limbs develop, the transcription factor HOX participates at two different stages: first to specify the asymmetrical formation of digits, then to help form different finger types.
- Phosphoryl Transfer and Calcium Ion Occlusion in the Calcium Pump
The calcium pump moves ions across cell membranes by phosphorylation-induced occlusion of one end of the pore to prevent ions from slipping backward; relaxing this high-energy state releases the ions on the other side.
- Msx1 Cooperates with Histone H1b for Inhibition of Transcription and Myogenesis
Linker histones, proteins known to suppress gene activity by condensing chromatin, also activate genes involved in muscle development by binding to other regulatory proteins.
- Acidic Mammalian Chitinase in Asthmatic Th2 Inflammation and IL-13 Pathway Activation
A human enzyme that can degrade the chitin of insect exoskeletons also regulates allergic inflammation in asthma, reinforcing the similarities between immune responses to parasitic and allergic stimuli.
- Word Learning in a Domestic Dog: Evidence for "Fast Mapping"
A smart dog can learn new words rapidly and hold them in memory for up to 4 weeks, perhaps employing a basic learning mechanism that humans also use.