New water cycle on Mars discovered

Approximately every two Earth years, when it is summer on the southern hemisphere of Mars, a window opens: Only in this season can water vapor efficiently rise from the lower into the upper Martian atmosphere. There, winds ...

New research finds that viruses may have 'eyes and ears' on us

New UMBC-led research in Frontiers in Microbiology suggests that viruses are using information from their environment to "decide" when to sit tight inside their hosts and when to multiply and burst out, killing the host cell. ...

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Cycling

Cycling, also called bicycling or biking, is the use of bicycles for transport, recreation, or for sport. Persons engaged in cycling are cyclists or bicyclists. Apart from ordinary two-wheeled bicycles, cycling also includes riding unicycles, tricycles, quadracycles, and other similar human-powered vehicles (HPVs).

Bicycles were introduced in the 19th century and now number about one billion worldwide. They are the principal means of transportation in many regions.

Cycling is a very efficient and effective mode of transportation optimal for short to moderate distances. Bicycles provide numerous benefits compared to motor vehicles, including exercise, an alternative to the use of fossil fuels, no air or noise pollution, much reduced traffic congestion, easier parking, greater maneuverability, and access to both roads and paths. The advantages are at less financial cost to the user as well as society (negligible damage to roads, and less pavement required). Criticisms and disadvantages of cycling include reduced protection in crashes, particularly with motor vehicles, longer travel time (except in densely populated areas), vulnerability to weather conditions, difficulty in transporting passengers, and the skill and fitness required.

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