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Scanning electron micrograph of rods of Escherichia coli

Bacteria are ubiquitous, mostly free-living microorganisms often consisting of one biological cell. They constitute a domain of prokaryotic microorganisms. Among the first life forms to appear on Earth, bacteria are present in most habitats. They are vital in many stages of the nutrient cycle, where they recycle nutrients. The study of bacteria is known as bacteriology, a branch of microbiology. Humans and most other animals carry millions of bacteria; most bacteria in and on the body are harmless or rendered so by the immune system, and many are beneficial. Several species are pathogenic and cause infectious diseases. Antibiotics are used to treat bacterial infections and are also used in farming, making antibiotic resistance a growing problem. Bacterial cells do not contain a nucleus and rarely harbour membrane-bound organelles. Their scientific classification changed after the discovery in the 1990s that prokaryotes consist of two groups of organisms that evolved from a common ancestor. (Full article...)

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Did you know ...

Margery Jackson's court mantua

... that Carlisle miser Margery Jackson, who chose to live like a pauper, possessed a fine court mantua (pictured)?
... that The Steranko History of Comics has been described as the first piece of cultural analysis on American comic books?
... that Heinz Schwarz attended all CDU party conventions from the first ever in 1950 to 2020?
... that the Lewis and Clark Expedition documented the Ionia Volcano?
... that although he only had ten minutes to learn to play offensive lineman, college football player Jake Witt was able to successfully block against "the best defensive line" in the U.S.?
... that the Irish N53 road from Dundalk to Castleblayney has a 6-kilometre (3.7 mi) gap where it enters Northern Ireland?
... that Cambodia's first science-fiction film, Karmalink, combines Buddhist concepts of karma with themes of artificial intelligence?
... that Émile Aubrun flew circles around a golden virgin?

In the news

Kelvin Kiptum

In the London Marathon, Sifan Hassan wins the women's race, while Kelvin Kiptum (pictured) wins the men's event and breaks the course record.
The wreckage of the Montevideo Maru, a Japanese vessel sunk by the US during World War II with over 1,000 captive Australian nationals onboard, is discovered in the South China Sea.
SpaceX Starship, the most powerful rocket to date, is launched from Texas and destroyed almost four minutes into the flight.

On this day

April 27: Koningsdag in the Netherlands

Raising the Flag on the Three-Country Cairn

630 – Shahrbaraz usurped the throne of the Sasanian Empire from Ardashir III, but was himself killed six weeks later.
1650 – Wars of the Three Kingdoms: Covenanter forces defeated the Royalists at the Battle of Carbisdale near the village of Culrain, Scotland.
1945 – World War II: The photograph Raising the Flag on the Three-Country Cairn (pictured) was taken after German troops withdrew to Norway at the end of the Lapland War.
1965 – Indonesia–Malaysia confrontation: British forces repelled a surprise Indonesian attack on a base at Plaman Mapu in Sarawak.
2005 – The Airbus A380, the world's largest passenger airliner, made its maiden flight from Toulouse, France.

Ulysses S. Grant (b. 1822)
Sheila Scott (b. 1922)
Olivier Messiaen (d. 1992)

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Today's featured picture

Panorama of the Western Ghats during the dry season

Panorama of the Western Ghats during the monsoon

The monsoon of South Asia is one of the world's monsoons, affecting the Indian subcontinent. Because of its effect on agriculture, on flora and fauna, and on the climates of nations including Bangladesh, Bhutan, India, Nepal, Pakistan and Sri Lanka, the monsoon is one of the most anticipated, tracked and studied weather phenomena in the region. The southwest monsoon generally starts on the western coast of India at the beginning of June, and runs through to the beginning of October. Its cause is only partly understood and it is notoriously difficult to predict, with several theories proposed to explain its origin and process. These two panoramic photographs, taken three months apart in 2010 from the same location, show a view of the Western Ghats in Maharashtra, India, during the dry season in late May (top) and during the peak of the South Asian monsoon in late August (bottom).

Photograph credit: Arne Hückelheim

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