Interferons are signaling proteins in immune systems that have long been appreciated for their role in defending the body against viral attacks. Interferons hinder viruses from multiplying inside host cells, activate killer cells and macrophages (engulfing cells), and communicate with lymphocytes to help host cells deal with viral infection.

Flesh-eating zombies may be the work of science fiction horror, but necrotizing soft tissue infection—a severe type of infection that destroys tissue—is a real condition that can kill about 30 percent of those infected and disfigure the rest.

Recently, President George W. Bush stated that he believes that the concept of evolution does not conflict with a belief that God created the world.

The evolutionary story holds that nature favors efficiency in hunting and movement, but it turns out that cats contradict that concept.

Emergency brakes are an important safety component in elevators. In a dangerous episode, such as an earthquake, these brakes activate and stop the elevator from moving, keeping the passengers inside from plunging to the bottom floor.