A version of this story appears in the September 2020 issue of National Geographic magazine. Philadelphia detected its first case of a deadly, fast-spreading strain of influenza on September 17, 1918.

J.B. Maverick is an active trader, commodity futures broker, and stock market analyst 17+ years of experience, in addition to 10+ years of experience as a finance writer and book editor. David ...

A combination of transformations can sometimes be described using a single transformation, eg when a shape is transformed by two consecutive translations, the result can be expressed as a single ...

Investopedia contributors come from a range of backgrounds, and over 25 years there have been thousands of expert writers and editors who have contributed. Erika Rasure is globally-recognized as a ...

Memory is the faculty by which the brain encodes, stores, and retrieves information. It is a record of experience that guides future action. Memory encompasses the facts and experiential details that ...

If you could save lives by producing vaccines in transgenic bananas, would you? In the debate over large-scale commercialization and use of GMOs, where should we draw the line? Vaccines Tobacco ...

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Soil microbiology is enjoying a period of challenge and discovery made possible by the availability of new approaches for characterizing microbial communities and for imaging the soil environment.