Adolescent girls who think they are overweight, but are not, are at more risk for depression than girls who are overweight and know it, according to sociologists.

Hydrogen is the most abundant element in the universe and is a major component of giant planets such as Jupiter and Saturn. But not much is known about what happens to this abundant element under high-pressure conditions when it transforms from one state to another.

Chemists have created crystals that can twist and untwist, pointing to a much more varied process of crystal growth than previously thought. Their work may explain some of the properties of high-polymers, which are used in clothing and liquid crystal displays, among other consumer products.

A well-preserved tomb of an ancient Mayan king has been discovered in Guatemala. The tomb is packed with carvings, ceramics, textiles, and the bones of six children, who may have been sacrificed at the time of the king's death.

Seemingly redundant portions of the fruit fly genome may not be so redundant after all. Repeated instructional regions in the flies' DNA may contribute to normal development under less-than-ideal growth conditions by making sure that genes are turned on and off at the appropriate times, according to new research. If similar regions are found in humans, they may hold important clues to understanding developmental disorders.

Your skin tone and the amount of sunshine you receive -- in addition to what foods you eat -- all can influence the amount of vitamin D that your body has on hand for optimum health. Scientists have now developed a preliminary model that predicts an individual's vitamin D requirements.

Typically, migraine is considered to be an episodic disorder with discrete attacks of headache. But new research has found increased network activity -- stronger functional connectivity -- bilaterally in the visual, auditory and sensorimotor network in migraineurs.

Geophysicists have developed a new theory to explain the global motions of tectonic plates on the earth's surface. The new theory extends the theory of plate tectonics -- a kinematic description of plate motion without reference to the forces behind it -- with a dynamical theory that provides a physical explanation for both the motions of tectonic plates as well as motion of plate boundaries.

A research project to identify all the surface proteins of USA300 -- the most common community-associated strain of the methicillin-resistant form of the bacterium Staphylococcus aureus -- has resulted in the identification and isolation of a plentiful new toxin that laboratory studies indicate is a potent killer of human immune cells. Scientists say the toxin could be a key factor in the severity of MRSA infections in otherwise healthy people.

Two compounds emitted by mosquito predators that make the mosquitoes less inclined to lay eggs in pools of water may provide new environmentally friendly tactics for repelling and controlling disease-carrying insects.