Vaccination

Discovery sets stage for vaccine against gastric cancer, ulcers

H. pylori is one of the most common disease-causing bacteria. More than half of the world's population have the bacteria in their body; and while in Canada overall prevalence of H. pylori is between 20% and 30%, some groups—including ...

Light

Light is electromagnetic radiation, particularly radiation of a wavelength that is visible to the human eye (about 400–700 nm, or perhaps 380–750 nm.) In physics, the term light sometimes refers to electromagnetic radiation of any wavelength, whether visible or not.

Three primary properties of light are:

Light, which exists in tiny "packets" called photons, exhibits properties of both waves and particles. This property is referred to as the wave–particle duality. The study of light, known as optics, is an important research area in modern physics.

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