Wikipedia:Main Page history/2011 June 21

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Today's featured article
Thyrotoxic periodic paralysis is a condition featuring attacks of muscle weakness in the presence of hyperthyroidism (overactivity of the thyroid gland pictured). Hypokalemia (decreased potassium levels in the blood) is usually present during attacks. The condition may be life-threatening if weakness of the breathing muscles leads to respiratory failure, or if the low potassium levels lead to cardiac arrhythmias (irregularities in the heart rate). If untreated, it is typically recurrent in nature. The condition has been linked with genetic mutations in genes that code for certain ion channels that transport electrolytes (sodium and potassium) across cell membranes. Treatment of the hypokalemia, followed by correction of the hyperthyroidism, leads to complete resolution of the attacks. It occurs predominantly in males of Chinese, Japanese, Vietnamese, Filipino, and Korean descent. Thyrotoxic periodic paralysis is one of several conditions that can cause periodic paralysis. (more...) Recently featured: First Roumanian-American congregation – Adrian Cole – Gamma-ray burst Archive – By email – More featured articles...
Did you know...
From Wikipedia's newest content: ... that China's first female director was adopted by the first Premier of the People's Republic of China (pictured together in Moscow)? ... that the 1911 Sarez earthquake triggered a huge landslide, forming the tallest dam in the world? ... that Daysland, Alberta, is named after the Canadian politician Edgerton W. Day? ... that a significant part of the former Santo Domingo monastery in Chiapa de Corzo, Chiapas, is taken up by a museum dedicated entirely to lacquerware? ... that Lincoln Park in Jersey City, New Jersey, boasts the world's largest concrete monument, a fountain? ... that María de las Mercedes Barbudo is known as Puerto Rico's first female freedom fighter for her strong advocacy for Puerto Rico's independence from Spain? ... that the Southwestern pygmy possum can give birth just two days after weaning a previous litter, even though this requires dramatic changes to her mammary glands? Archive – Start a new article – Nominate an article

In the news
Zine El Abidine Ben Ali Former Tunisian President Zine El Abidine Ben Ali (pictured) is sentenced to 35 years in jail in absentia. RusAir Flight 9605 crashes in Petrozavodsk, Russia, killing 44 people. ICANN votes for an expansion of the available generic top-level domains, allowing companies and organizations to choose their own suffixes. Northern Irish golfer Rory McIlroy wins the U.S. Open with a record score of 16 under par. In response to ongoing protests in Morocco, King Mohammed VI announces constitutional reform proposals to be voted on in a referendum. Wikinews – Recent deaths – More current events...
On this day...
June 21: June Solstice (17:16 UTC, 2011); International Surfing Day; National Aboriginal Day in Canada 217 BC – Second Punic War: The Carthaginians under Hannibal executed one of the largest military ambushes in history when they overwhelmingly defeated the Romans. 1826 – Greek War of Independence: A combined Egyptian and Ottoman army began their invasion of the Mani Peninsula, but they were initially held off by the Maniots at the fortifications of Vergas. 1919 – Admiral Ludwig von Reuter scuttled the German High Seas Fleet in Scapa Flow to prevent the ships from being seized and divided amongst the Allied Powers. 1948 – The Manchester Small-Scale Experimental Machine, the world's first stored-program computer, ran its first computer program. 2004 – SpaceShipOne (pictured) completed the first privately funded human spaceflight. More anniversaries: June 20 – June 21 – June 22 Archive – By email – List of historical anniversaries It is now June 21, 2011 (UTC) – Refresh this page

Today's featured picture

A World War I Ottoman crew operating a heliograph, a wireless solar telegraph that signals using Morse code flashes of sunlight reflected by a mirror. It is operated by pivoting the mirror or by interrupting the beam with a shutter, and is a simple but highly effective instrument for instantaneous optical communication over long distances, with the record being 183 mi (295 km).

Photo: American Colony; Restoration: Lise Broer

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