Earth

OAK RIDGE, Tenn. Feb. 7, 2011 -- Neutron scattering analysis of two families of iron-based materials suggests that the magnetic interactions thought responsible for high-temperature superconductivity may lie "two doors down": The key magnetic exchange pairings occur in a next-nearest-neighbor ordering of atoms, rather than adjacent atoms.

Elements heavier than iron come into being only in powerful stellar explosions, supernovae. During nuclear reactions all kinds of short-lived atomic nuclei are formed, including more stable combinations – the so-called magic numbers – predicted by theory. Yet here, too, there are exceptions: the islands of inversion. Headed by physicists from the Excellence Cluster Universe at the Technische Universitaet Muenchen (TUM), an international team of scientists has now taken a closer look at the island that was first discovered.

Nacre, commonly known as mother-of-pearl, is the iridescent material lining many mollusk shells. It is part of a two-layer armor system that protects the animal from predators. The brittle outer layer of the shell absorbs the initial impact, but is prone to cracking. To prevent these cracks from catastrophically propagating through the shell to the animal itself, the nacreous layer is surprisingly strong and tough, with outstanding crack arresting properties. Thus it acts as a lining to maintain the integrity of the shell in the event of cracking of the outer layer.

Faulted terrace risers place new constraints on the late Quaternary slip rate for the central Altyn Tagh fault, northwest TibetRyan D. Gold et al., Dept. of Geology, University of California, Davis, California 95616, USA. Published online 28 Jan. 2011; doi: 10.1130/B30207.1.

BOULDER, Colo.—In a paradox typical of the quantum world, JILA scientists have eliminated collisions between atoms in an atomic clock by packing the atoms closer together. The surprising discovery, described in the Feb. 3 issue of Science Express,* canboost the performance of experimental atomic clocks made of thousands or tens of thousands of neutral atoms trapped by intersecting laser beams.

JILA is jointly operated by the National Institute of Standards and Technology (NIST) and the University of Colorado Boulder.

A new way of splitting layered materials to give atom thin "nanosheets" has been discovered. This has led to a range of novel two-dimensional nanomaterials with chemical and electronic properties that have the potential to enable new electronic and energy storage technologies. The collaborative* international research led by the Centre for Research on Adaptive Nanostructures and Nanodevices (CRANN), Trinity College Dublin, Ireland, and the University of Oxford has been published in this week's Science.

One of the most significant socioeconomic changes in the history of humanity took place around 10,000 years ago, when the Near East went from an economy based on hunting and gathering (Mesolithic) to another kind on agriculture (Neolithic). Farmers rapidly entered the Balkan Peninsula and then advanced gradually throughout the rest of Europe.

New experiments show that common scientific rules can apply to significantly different phenomena operating on vastly different scales.

The results raise the possibility of making discoveries pertaining to phenomena that would be too large or impractical to recreate in the laboratory, said Cheng Chin, associate professor in physics and the James Franck Institute at the University of Chicago. Chin and associates Chen-Lung Hung, Xibo Zhang and Nathan Gemelke published their results in the Jan. 26 Advance Online Publication (Feb. 10 print edition) of the journal Nature.

RENO, Nev. – A team of University of Nevada, Reno and University of Nevada, Las Vegas researchers have devised a new model for how Nevada's gold deposits formed, which may help in exploration efforts for new gold deposits.

They were called the Eighth Wonder of the World. Until the late 19th century, New Zealand's Pink and White Terraces along Lake Rotomahana on the North Island, attracted tourists from around the world, interested in seeing the beautiful natural formations created by a large geothermal system. But the eruption of Mt. Tarawera on June 10, 1886, buried the terraces in sediment and caused the lake basin to enlarge, engulfing the land where the terraces stood. For more than a century, people have speculated whether any part of the Pink and White Terraces survived the eruption.

BOULDER--The aggressive wolverine may not be powerful enough to survive climate change in the contiguous United States, new research concludes.

ITHACA, N.Y. – Growing up poor increases a person's likelihood of health problems as an adult, but a new study led by a Cornell University environmental psychologist shows that being raised in a tight-knit community can help offset this disadvantage of poverty.

Failure to tackle rising greenhouse gas emissions effectively has led to intensifying debate on geoengineering - deliberate large-scale schemes to slow the rate at which Earth is heating up. The public debate often mixes opinion with fact so scientists have now released the first summary for policymakers on ocean fertilization, one of the earliest geoengineering proposals. The authors report that the chances of success of using ocean fertilization to deal with climate change is low.

Ecology drives evolution. In today's issue of the journal Science, UC Davis expert Thomas Schoener describes growing evidence that the reverse is also true, and explores what that might mean to our understanding of how environmental change affects species and vice-versa.