Earth

PROVIDENCE, R.I. [Brown University] — Large chunks of an ancient tectonic plate that slid under North America millions of years ago are still present under parts of central California and Mexico, according to new research led by Brown University geophysicists.

Computer simulations of water under extreme pressure are helping geochemists understand how carbon might be recycled from hundreds of miles below the Earth's surface. The work, by researchers at the University of California, Davis, and Johns Hopkins University, is published March 18 in the journal Proceedings of the National Academy of Sciences.

RIVERSIDE, Calif. — A research team led by biogeochemists at the University of California, Riverside has filled in a billion-year gap in our understanding of conditions in the early ocean during a critical time in the history of life on Earth.

One of the most basic laws of quantum mechanics is that a system can be in more than one state – it can exist in multiple realities – at once. This phenomenon, known as the superposition principle, exists only so long as the system is not observed or measured in any way. As soon as such a system is measured, its superposition collapses into a single state. Thus, we, who are constantly observing and measuring, experience the world around us as existing in a single reality.

The pale cyst nematode, Globodera pallida, is one bad roundworm.

Unchecked, the pest burrows into potato roots to feed, obstructing nutrients and causing stunted growth, wilted leaves and other symptoms that can eventually kill the plant. Severe infestations can cause tuber yield losses of up to 80 percent.

Now, however, U.S. Department of Agriculture (USDA) and cooperating scientists are evaluating new ways to control G. pallida using naturally occurring chemicals called egg-hatching factors.

Irvine, Calif. –Models of carbon dioxide in the world's oceans need to be revised, according to new work by UC Irvine and other scientists published online Sunday in Nature Geoscience. Trillions of plankton near the surface of warm waters are far more carbon-rich than has long been thought, they found. Global marine temperature fluctuations could mean that tiny Prochlorococcus and other microbes digest double the carbon previously calculated. Carbon dioxide is the leading driver of disruptive climate change.

There's little doubt — among scientists at any rate — that the climate has warmed since people began to release massive amounts greenhouse gases to the atmosphere during the Industrial Revolution.

But ask a scientist if the weather is getting stormier as the climate warms and you're likely to get a careful response that won't make for a good quote.

There's a reason for that.

In about a third of the global ocean, the abundance of life is limited by a dearth of biologically available iron.

The supply of iron to a region that is depleted in this important nutrient can stimulate algal productivity, and can result in a temporary boom in biological activity.

For much of the surface ocean, the wind-borne transport of iron-rich dust and the upwelling of nutrient-filled water are the major sources of iron. Another potentially important source is the deposition of the iron-rich ash produced by volcanic eruptions.

The dry, barren prairie around Alberta's Drumheller area was once a lush and subtropical forest on the shores of a large inland sea, with loads of wetlands inhabited by dinosaurs, turtles, crocodiles and small mammals.

Scientist from Dortmund, Helsinki, Potsdam, and the ESRF have revealed details of the microscopic atomic structure of water under extreme conditions. The results have now been published in the Proceedings of the National Academy of Sciences of the USA.

A U.S. Department of Agriculture (USDA) scientist is giving guidance to growers in Montana and the Dakotas on how grazing sheep when fields are left fallow will affect soil quality.

How you get the chameleon of the molecules to settle on a particular "look" has been discovered by RUB chemists led by Professor Dominik Marx. The molecule CH5+ is normally not to be described by a single rigid structure, but is dynamically flexible. By means of computer simulations, the team from the Centre for Theoretical Chemistry showed that CH5+ takes on a particular structure once you attach hydrogen molecules. "In this way, we have taken an important step towards understanding experimental vibrational spectra in the future", says Dominik Marx.

The precise methodology of Richard Feynman's famous double-slit thought-experiment – a cornerstone of quantum mechanics that showed how electrons behave as both a particle and a wave – has been followed in full for the very first time.

Although the particle-wave duality of electrons has been demonstrated in a number of different ways since Feynman popularised the idea in 1965, none of the experiments have managed to fully replicate the methodology set out in Volume 3 of Feynman's famous Lectures on Physics.

Earth is the only known planet that holds water in massive quantities and in all three phase states. But the earthly, omnipresent compound water has very unusual properties that become particularly evident when subjected to high pressure and high temperatures. In the latest issue of the Proceedings of the National Academy of Sciences (PNAS), a German-Finnish-French team published what happens when water is subjected to pressure and temperature conditions such as those found in the deep Earth.

A study published this week in PLOS Medicine finds that while antipsychotic medications are associated with small-to-moderate improvements in depressive symptoms in adults, there is little evidence for improvement on measures of quality of life and these medications are linked to adverse events such as weight gain and sedation.