Virus

A virus is a small infectious agent that replicates only inside the living cells of other organisms. Viruses can infect all types of life forms, from animals and plants to microorganisms, including bacteria and archaea.

Since Dmitri Ivanovsky's 1892 article describing a non-bacterial pathogen infecting tobacco plants, and the discovery of the tobacco mosaic virus by Martinus Beijerinck in 1898, about 5,000 virus species have been described in detail, although there are millions of types. Viruses are found in almost every ecosystem on Earth and are the most abundant type of biological entity. The study of viruses is known as virology, a sub-speciality of microbiology.

While not inside an infected cell or in the process of infecting a cell, viruses exist in the form of independent particles. These viral particles, also known as virions, consist of two or three parts: (i) the genetic material made from either DNA or RNA, long molecules that carry genetic information; (ii) a protein coat, called the capsid, which surrounds and protects the genetic material; and in some cases (iii) an envelope of lipids that surrounds the protein coat when they are outside a cell. The shapes of these virus particles range from simple helical and icosahedral forms for some virus species to more complex structures for others. Most virus species have virions that are too small to be seen with an optical microscope. The average virion is about one one-hundredth the size of the average bacterium.

Dr. Mario

Dr. Mario (Japanese: ドクターマリオ, Hepburn: Dokutā Mario, often stylized as D℞. Mario) is a 1990 Mario arcade-style action puzzle video game designed by Gunpei Yokoi and produced by Takahiro Harada. Nintendo developed and published the game for the Nintendo Entertainment System and Game Boy consoles. The game's soundtrack was composed by Hirokazu Tanaka.

The game focuses on the player character Mario, who assumes the role of a doctor and is tasked with eradicating deadly viruses. In this falling block puzzle game, the player's objective is to destroy the viruses populating the on-screen playing field by using colored capsules that are dropped into the field. The player manipulates the capsules as they fall so that they are aligned with viruses of matching colors, which removes them from play. The player progresses through the game by eliminating all the viruses on the screen in each level.

Dr. Mario received positive reception, appearing on several "Best Nintendo Games of All Time" lists. The game has been ported, remade, or has had a sequel on every Nintendo home console since the NES as well as most portable consoles, including a re-release in 2004 on the Game Boy Advance as part of the Classic NES Series. Modified versions of Dr. Mario exist as minigames in WarioWare, Inc.: Mega Microgames!, Brain Age 2: More Training in Minutes a Day!, and Brain Age: Concentration Training.

Viruses (journal)

Viruses is a peer-reviewed open access scientific journal published by MDPI covering all aspects of virology. It was established in 2009. The editor-in-chief is Eric O. Freed.

Abstracting and indexing

The journal is abstracted and indexed in:

According to the Journal Citation Reports, the journal has a 2013 impact factor of 3.279.

References

External links