Scientists have long struggled to understand what regulates sperm “capacitation,” the vital physiological process sperm must undergo to become capable of fertilizing an egg cell. Zinc plays a critical role.
There's a mysterious and sometimes deadly weather pattern in which the jet stream stalls out over a region. A University of Chicago study explains the blocking phenomenon that has baffled forecasters until now.
Despite a wild fall, National Oceanic and Atmospheric Administration (NOAA) expects a warmer-than-normal winter for the western two-thirds of the U.S. They don’t expect any areas with cooler-than-normal conditions.