Testing the saliva of healthy older people for the level of the stress hormone cortisol may help identify individuals who should be screened for problems with thinking skills, according to a study published in Neurology. The study found that people with higher levels of cortisol in the evening were more likely to have a smaller total brain volume and to perform worse on tests of thinking and memory skills.

Could the sperm harpoon the egg to facilitate fertilization? That's the intriguing possibility raised by the University of Virginia School of Medicine's discovery that a protein within the head of the sperm forms spiky filaments, suggesting that these tiny filaments may lash together the sperm and its target.

The finding, 14 years in the making, has earned the cover of the scientific journal Andrology. It represents a significant step forward in the fine dissection of the protein architecture of the sperm's acrosomal matrix, an organelle in the sperm head, and suggests a new hypothesis concerning what happens during fertilization.

A new device transforms paralysis victims’ breath into words.

Billed as a tool to help bring back the art of conversation for sufferers of severe paralysis and loss of speech, the prototype analyses changes in breathing patterns and converts ‘breath signals’ into words using pattern recognition software and an analogue-to-digital converter. A speech synthesizer then reads the words aloud.

The Augmentative and Alternate Communication (AAC) device is designed for patients with complete or partial loss of voluntary muscle control who don’t have the ability to make purposeful movements such as sniffing or blinking – gestures which previous AAC devices have come to rely upon.

Before gluten sensitivity was a running joke in popular culture, medical marijuana held the preeminent position as easy humor fodder. The reason was simple: It did nothing for glaucoma, beyond the placebo range, and though the vast majority of clinical pain patients were women, 75 percent of the "medical marijuana" cardholders were men.

Parents go to great lengths to ensure the health and well-being of their developing offspring. The favor, however, may not always be returned.

Dramatic research has shown that during pregnancy, cells of the fetus often migrate through the placenta, taking up residence in many areas of the mother's body, where their influence may benefit or undermine maternal health.

The presence of fetal cells in maternal tissue is known as fetal microchimerism. The term alludes to the chimeras of ancient Greek myth--composite creatures built from different animal parts, like the goat-lion-serpent depicted in an Etruscan bronze sculpture.

If you are a hunter and accidentally shoot an endangered eagle, you could go to jail and you will certainly have a criminal record. If you are a wind turbine company, you kill 100 eagles a year and pay a token fine.  An estimated 75 to 110 golden eagles die at a wind-power generation operation in Altamont, California each year. That is about one eagle for every 8 megawatts of energy produced yet no one is in Federal prison.