In new research published in the prestigious journal Proceedings of the National Academy of Sciences (PNAS), a team of scientists from the Hebrew University Hadassah Medical School, in the Faculty of Medicine, unraveled a longstanding mystery of a fundamental property of the brain.

Many animals change sex at some point in their lives, often after reaching a certain size. Snails called slipper limpets begin life as males, and become female as they grow. A new Smithsonian study shows that when two males are kept together and can touch one another, the larger one changes to female sooner, and the smaller one later. Contact, rather than chemicals released into the water, is necessary for the effect.

"I was blown away by this result," said co-author Rachel Collin, staff scientist at the Smithsonian Tropical Research Institute (STRI). "I fully expected that the snails would use waterborne cues to see their world."

Forests help remove carbon dioxide from the atmosphere by storing it in trees, but a sizeable amount of the greenhouse gas actually escapes through the soil and into rivers and streams.

That's the main finding of a paper to appear Monday in the Proceedings of the National Academy of Sciences. It's the first study to comprehensively look at how carbon moves in freshwater across the entire U.S.

The researchers found that across the country, the ability of forests to store carbon is not as robust once freshwater is factored into the equation. They hope to introduce this as an important concept to consider when modeling how much carbon is stored in terrestrial landscapes.

When it comes to accurately identifying a criminal suspect, it makes a difference how sure an eyewitness is, finds a study led by a memory expert at the University of California, San Diego. The American justice system should take note of eyewitness confidence, but only at the time of the initial identification and not at a later date in court. Working with victims and bystanders of actual robberies, the study also finds in favor of the traditional lineup procedure that presents suspects at the same time as known innocents, instead of individually.

Scientists at the U.S. Department of Energy's Lawrence Berkeley National Laboratory (Berkeley Lab) have developed a novel electrolyte for use in solid-state lithium batteries that overcomes many of the problems that plague other solid electrolytes while also showing signs of being compatible with next-generation cathodes.

Berkeley Lab battery scientist Nitash Balsara, working with collaborator Joseph DeSimone of the University of North Carolina at Chapel Hill, came up with a highly conductive hybrid electrolyte, combining the two primary types of solid electrolytes--polymer and glass.

The brains of children who suffer clinical depression as preschoolers develop abnormally, compared with the brains of preschoolers unaffected by the disorder, according to new research at Washington University School of Medicine in St. Louis.

Their gray matter -- tissue that connects brain cells and carries signals between those cells and is involved in seeing, hearing, memory, decision-making and emotion -- is lower in volume and thinner in the cortex, a part of the brain important in the processing of emotions.

The new study is published Dec. 16 in JAMA Psychiatry.