Rain as acidic as undiluted lemon juice may have played a part in killing off plants and organisms around the world about 252 million years ago during the most severe mass extinction in Earth's history, known as the Great Dying.

The cause of such a massive extinction is an ongoing scientific debate, centering on several potential causes, including an asteroid collision similar to what likely killed off the dinosaurs 186 million years later; a gradual, global loss of oxygen in the oceans; and a cascade of environmental events triggered by massive volcanic eruptions in a region known today as the Siberian Traps.

Spontaneous bursts of light,
which last trillionths of a second, change color as they pulse from within a solid-state block
and illuminate the unusual way interacting quantum particles behave when they are driven far from equilibrium. A way to trigger these flashes may lead to new telecommunications equipment and other devices that transmit signals at picosecond speeds. 

The Rice University lab of Junichiro Kono said the phenomenon can be understood as a combination of two previously known many-body concepts: superfluorescence, as seen in atomic and molecular systems, and Fermi-edge singularities, a process known to occur in metals.

Though Europeans are commonly regarded by Americans as more accepting of climate science, when it comes to putting plans into action, that isn't the case. America has reduced its carbon dioxide emissions from energy back to early 1990s levels and its dirtiest emissions, from coal, back to early 1980s levels. Aside from mistaken ethanol and solar subsidies and mandates, this hasn't been done by mitigation, rationing or cost increases but by adopting cleaner natural gas.

People who get migraine headaches and also battle allergies and hay fever (rhinitis) endure a more severe form of headaches than their peers who struggle with migraines but aren't affected by the seasonal or year-round sniffles, according to a new paper in Cephalalgia.

About 12 percent of the U.S. population experiences migraine headaches and women get them three times more often than men. Allergies and hay fever — allergic rhinitis — are quite common as well, affecting up to a quarter to half of the U.S. population. They produce symptoms such as a stuffy and runny nose, post nasal drip and itching of the nose.  

Using advanced methodologies that pit drug compounds against specific types of malaria parasite cells, an international team of scientists have identified a potential new weapon and approach for attacking the parasites that cause malaria.  

The disease is caused by Plasmodium parasites, which are transmitted to humans by the infectious bite of an Anopheles mosquito. Plasmodium vivax and Plasmodium falciparum are the most problematic of the parasite species. The former is the most widespread globally; the latter most deadly.

Two subglacial
lakes, each roughly 8-10 km2,  have been discovered 800 meters below the Greenland Ice Sheet. At one point they may have been up to three times larger than their current size. 

Subglacial lakes are likely to influence the flow of the ice sheet, impacting global sea level change. The discovery of the lakes in Greenland will also help researchers to understand how the ice will respond to changing environmental conditions.

The study, conducted at the Scott Polar Research Institute (SPRI) at the University of Cambridge, used airborne radar measurements to reveal the lakes underneath the ice sheet.

Asparagine, which is found in foods such as meat, eggs, and dairy products, was once considered non-essential because it is also produced naturally by the body.

And that is true, for every organ except the brain, where the amino acid is essential for normal brain development. 

"The cells of the body can do without it because they use asparagine provided through diet. Asparagine, however, is not well transported to the brain via the blood-brain barrier," said senior co-author of the study Dr. Jacques Michaud, who found that brain cells depend on the local synthesis of asparagine to function properly. 

A person with a food allergy is more likely to be murdered than to die from a severe reaction, according to a new paper in Clinical and Experimental Allergy.

C/2012 S1, Comet ISON, is intriguing because it has never approached the sun before and that is scientifically terrific. 

Comet ISON began in the Oort cloud almost a light year away and has traveled for over a million years. Unlike more famous comets, Halley's as an example, it has never come this way before - and that means it is still made of pristine matter from the earliest days of the solar system's formation. Its top layers haven't been lost by a trip near the sun.

To study it as it approached Sol, a vast fleet of solar observation experiments have been watching. Would it break up or slingshot? 

Rip currents claim more lives in Australia on average each year than bushfires, floods, cyclones and sharks combined - but don't get too nervous, rip currents only cause about 21 confirmed human fatalities per year.

Rip currents are strong, narrow seaward-flowing currents that can easily carry unsuspecting swimmers significant distances offshore, leading to exhaustion, panic and often drowning.

An analysis of data from Australia's National Coronial Information System shows there was an average 21 confirmed deaths involving rips per year during the period 2004 to 2011.