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From today's featured article

Model of a SARS-CoV-2 virion
Model of a SARS-CoV-2 virion

A virus is a pathogen that replicates inside the cells of an organism. They are found in almost every ecosystem on Earth and infect all life forms. Since the discovery of the tobacco mosaic virus in 1898, more than 16,000 of the millions of virus species have been described. When infected, a host cell is often forced to produce thousands of copies of the virus. Outside an infected cell, viruses exist as virions, which consist of genetic material, the capsid that surrounds and protects the genetic material, and sometimes an outside envelope of lipids. Viruses can spread through disease-bearing organisms, airborne transmission, hand-to-mouth contact, ingesting food or water, and other means. Viral infections in animals provoke an immune response that usually eliminates the virus; viruses that evade immune responses result in chronic infections. Immune responses can be produced by vaccines, while antiviral drugs can be used to treat infections. (Fullarticle...)

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Pizza Cat with a morale patch bearing her likeness
Pizza Cat with a morale patch bearing her likeness
  • ... that Pizza Cat (pictured), a cat living at Al Udeid Air Base, was awarded the rank of "Senior Meowster Sergeant" by the United States Air Force?
  • ... that Ælfhun, Bishop of London, was accused of trying to remove the body of StEdmund, but the bier was said to have miraculously refused to move?
  • ... that a local official of the Joseon dynasty secretly buried the body of King Danjong despite King Sejo's threats to kill the family of anyone who did so?
  • ... that Ariana Grande claimed that she would need two brains and six arms to produce her eighth album before announcing Petal?
  • ... that a type of ballad details the fictionalized last words of executed people?
  • ... that a fixture of Madrid nightlife in the 1990s was a guitarist who was often seen at concerts wearing a large picture hat?
  • ... that Gambit Digital acquired the rights to the 2023 video game Fae Farm five days after the original developer ended online support in September2025?
  • ... that a dog chasing its master and a crab sidestepping an intruder can both be modeled mathematically by motion along a Tschirnhausen cubic?
  • ... that soon after the general Hushahu, fearing harsh punishment, assassinated his emperor, another general, also fearing harsh punishment, murdered him?
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July 9

Italian players celebrating their 2006 World Cup victory
Italian players celebrating their 2006 World Cup victory

Today's featured picture

Dictyophorus spumans, also known as the koppie foam grasshopper, is a species of grasshopper in the family Pyrgomorphidae, indigenous to southern Africa. The name "foam grasshopper" derives from the insect's ability to produce a toxic foam from its thoracic glands, using a combination of hemolymph with air from the grasshopper's spiracles. Adult males are typically 4.5 to 5cm (1.8 to 2.0in) long and females typically 5 to 7cm (2.0 to 2.8in), but can grow up to a length of 8cm (3.1in). This nymph of the subspecies D.s.spumans was photographed in the Walter Sisulu National Botanical Garden in Roodepoort, South Africa. Photograph credit: Charles J. Sharp Recently featured: Mango Nettie Stevens Silver certificate Archive More featured pictures

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