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๐ Corrupted Blood Incident
The Corrupted Blood incident was a virtual pandemic in the MMORPG World of Warcraft, which began on September 13, 2005, and lasted for one week. The epidemic began with the introduction of the new raid Zul'Gurub and its end boss Hakkar the Soulflayer. When confronted and attacked, Hakkar would cast a hit point-draining and highly contagious debuff spell called "Corrupted Blood" on players.
The spell, intended to last only seconds and function only within the new area of Zul'Gurub, soon spread across the virtual world by way of an oversight that allowed pets and minions to take the affliction out of its intended confines. By both accidental and purposeful intent, a pandemic ensued that quickly killed lower-level characters and drastically changed normal gameplay, as players did what they could do to avoid infection. Despite measures such as programmer-imposed quarantines, and the players' abandoning of densely populated cities (or even just not playing the game), it lasted until a combination of patches and resets of the virtual world finally controlled the spread.
The conditions and reactions of the event attracted the attention of epidemiologists for its implications of how human populations could react to a real-world epidemic.
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- "Corrupted Blood Incident" | 2023-08-24 | 110 Upvotes 40 Comments
- "Corrupted Blood Incident" | 2015-04-30 | 87 Upvotes 13 Comments
๐ Crop Milk
Crop milk is a secretion from the lining of the crop of parent birds in some species that is regurgitated to young birds. It is found among all pigeons and doves where it is also referred to as pigeon milk. Crop milk is also secreted from the crop of flamingos and the male emperor penguin, suggesting independent evolution of this trait. Unlike in mammals where only females produce milk, crop milk is produced by both males and females in pigeons and flamingos; and in penguins, only by the male. Lactation in birds is controlled by prolactin, which is the same hormone that causes lactation in mammals. Crop milk is a holocrine secretion, unlike in mammals where milk is an exocrine secretion. Crop milk contains both fat and protein, as with mammalian milk, but unlike mammalian milk, it contains no carbohydrates.
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- "Crop Milk" | 2023-07-23 | 25 Upvotes 4 Comments
๐ The Real Book
The Real Book is a musicians' fake book โ a compilation of lead sheets for jazz standards. Fake books had been around at least since the late 1920s, but their organization was haphazard, and their content did not always keep pace with contemporary musical styles. The Real Book was initially produced by two students at the Berklee College of Music in the 1970s, as an updated fake book. It became so popular that the books was eventually "legitimized" by publisher Hal Leonard, and re-released in a series of editions and transpositions for various instruments.
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- "The Real Book" | 2023-01-26 | 61 Upvotes 39 Comments
๐ Woo! Yeah!
Woo! Yeah! is a drum break that includes James Brown's ("Woo!") and Bobby Byrd's ("Yeah!") voices which has been widely sampled in popular music, often in the form of a loop. The drum break was performed by John "Jabo" Starks. It originates from the 1972 Lyn Collins recording "Think (About It)", a song written and produced by Brown, and is just one of a few other frequently used breaks contained in the recording, often collectively known as the Think Break.
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- "Woo! Yeah!" | 2021-07-16 | 16 Upvotes 3 Comments
๐ The Pioneer Anomaly
The Pioneer anomaly or Pioneer effect was the observed deviation from predicted accelerations of the Pioneer 10 and Pioneer 11 spacecraft after they passed about 20 astronomical units (3ร109ย km; 2ร109ย mi) on their trajectories out of the Solar System. The apparent anomaly was a matter of much interest for many years but has been subsequently explained by an anisotropic radiation pressure caused by the spacecraft's heat loss.
Both Pioneer spacecraft are escaping the Solar System but are slowing under the influence of the Sun's gravity. Upon very close examination of navigational data, the spacecraft were found to be slowing slightly more than expected. The effect is an extremely small acceleration towards the Sun, of (8.74ยฑ1.33)ร10โ10ย m/s2, which is equivalent to a reduction of the outbound velocity by 1ย km/h over a period of ten years. The two spacecraft were launched in 1972 and 1973. The anomalous acceleration was first noticed as early as 1980 but not seriously investigated until 1994. The last communication with either spacecraft was in 2003, but analysis of recorded data continues.
Various explanations, both of spacecraft behavior and of gravitation itself, were proposed to explain the anomaly. Over the period from 1998 to 2012, one particular explanation became accepted. The spacecraft, which are surrounded by an ultra-high vacuum and are each powered by a radioisotope thermoelectric generator (RTG), can shed heat only via thermal radiation. If, due to the design of the spacecraft, more heat is emitted in a particular direction by what is known as a radiative anisotropy, then the spacecraft would accelerate slightly in the direction opposite of the excess emitted radiation due to the recoil of thermal photons. If the excess radiation and attendant radiation pressure were pointed in a general direction opposite the Sun, the spacecraft's velocity away from the Sun would be decreasing at a rate greater than could be explained by previously recognized forces, such as gravity and trace friction due to the interplanetary medium (imperfect vacuum).
By 2012 several papers by different groups, all reanalyzing the thermal radiation pressure forces inherent in the spacecraft, showed that a careful accounting of this explains the entire anomaly; thus the cause is mundane and does not point to any new phenomenon or need for a different physical paradigm. The most detailed analysis to date, by some of the original investigators, explicitly looks at two methods of estimating thermal forces, concluding that there is "no statistically significant difference between the two estimates and [...] that once the thermal recoil force is properly accounted for, no anomalous acceleration remains."
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- "The Pioneer Anomaly" | 2011-03-04 | 52 Upvotes 10 Comments
๐ Acrostic
An acrostic is a poem (or other form of writing) in which the first letter (or syllable, or word) of each line (or paragraph, or other recurring feature in the text) spells out a word, message or the alphabet. The word comes from the French acrostiche from post-classical Latin acrostichis, from Koine Greek แผฮบฯฮฟฯฯฮนฯฮฏฯ, from Ancient Greek แผฮบฯฮฟฯ "highest, topmost" and ฯฯฮฏฯฮฟฯ "verse". As a form of constrained writing, an acrostic can be used as a mnemonic device to aid memory retrieval.
Relatively simple acrostics may merely spell out the letters of the alphabet in order; such an acrostic may be called an 'alphabetical acrostic' or abecedarius. These acrostics occur in the first four of the five chapters that make up the Book of Lamentations, in the praise of the good wife in Proverbs 31:10-31, and in Psalms 25, 34, 37, 111, 112, 119 and 145 of the Hebrew Bible. Notable among the acrostic Psalms is the long Psalm 119, which typically is printed in subsections named after the 22 letters of the Hebrew alphabet, each section consisting of 8 verses, each of which begins with the same letter of the alphabet and the entire psalm consisting of 22 x 8 = 176 verses; and Psalm 145, which is recited three times a day in the Jewish services. Some acrostic psalms are technically imperfect. E.g. Psalm 9 and Psalm 10 appear to constitute a single acrostic psalm together, but the length assigned to each letter is unequal and five of the 22 letters of the Hebrew alphabet are not represented and the sequence of two letters is reversed. In Psalm 25 one Hebrew letter is not represented, the following letter (Resh) repeated. In Psalm 34 the current final verse, 23, does fit verse 22 in content, but adds an additional line to the poem. In Psalms 37 and 111 the numbering of verses and the division into lines are interfering with each other; as a result in Psalm 37, for the letters Daleth and Kaph there is only one verse, and the letter Ayin is not represented. Psalm 111 and 112 have 22 lines, but 10 verses. Psalm 145 does not represent the letter Nun, having 21 one verses, but one Qumran manuscript of this Psalm does have that missing line, which agrees with the Septuagint.
Acrostics are common in medieval literature, where they usually serve to highlight the name of the poet or his patron, or to make a prayer to a saint. They are most frequent in verse works but can also appear in prose. The Middle High German poet Rudolf von Ems for example opens all his great works with an acrostic of his name, and his world chronicle marks the beginning of each age with an acrostic of the key figure (Moses, David, etc.). In chronicles, acrostics are common in German and English but rare in other languages.
Often the ease of detectability of an acrostic can depend on the intention of its creator. In some cases an author may desire an acrostic to have a better chance of being perceived by an observant reader, such as the acrostic contained in the Hypnerotomachia Poliphili (where the key capital letters are decorated with ornate embellishments). However, acrostics may also be used as a form of steganography, where the author seeks to conceal the message rather than proclaim it. This might be achieved by making the key letters uniform in appearance with the surrounding text, or by aligning the words in such a way that the relationship between the key letters is less obvious. This is referred to as null ciphers in steganography, using the first letter of each word to form a hidden message in an otherwise innocuous text. Using letters to hide a message, as in acrostic ciphers, was popular during the Renaissance, and could employ various methods of enciphering, such as selecting other letters than initials based on a repeating pattern (equidistant letter sequences), or even concealing the message by starting at the end of the text and working backwards.
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- "Acrostic" | 2019-10-11 | 18 Upvotes 3 Comments
๐ Ganjifa
Ganjifa, Ganjapa or Gรขnjaphรข, is a card game and type of playing cards that are most associated with Persia and India. After Ganjifa cards fell out of use in Iran before the twentieth century, India became the last country to produce them. The form prevalent in Odisha is Ganjapa.
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- "Ganjifa" | 2024-06-02 | 100 Upvotes 28 Comments
๐ Kvass
Kvass is a fermented cereal-based non-alcoholic or low alcoholic (0.5โ1.0% or 1โ2 proof) beverage with a slightly cloudy appearance, light-dark brown colour and sweet-sour taste. It may be flavoured with berries, fruits, herbs, honey
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- "Kvass" | 2022-02-04 | 22 Upvotes 13 Comments
๐ Sir Douglas Nicholls
Sir Douglas Ralph Nicholls, (9 December 1906 โ 4 June 1988) was a prominent Aboriginal Australian from the Yorta Yorta people. He was a professional athlete, Churches of Christ pastor and church planter, ceremonial officer and a pioneering campaigner for reconciliation.
Nicholls was the first Aboriginal Australian to be knighted when he was appointed Knight Bachelor in 1972 (he was subsequently appointed a Knight Commander of the Royal Victorian Order in 1977). He was also the first โ and to date the only โ Indigenous Australian to be appointed to vice-regal office, serving as Governor of South Australia from 1 December 1976 until his resignation on 30 April 1977 due to poor health.
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- "Sir Douglas Nicholls" | 2021-04-29 | 55 Upvotes 17 Comments
๐ Abductive Logic Programming
Abductive logic programming (ALP) is a high-level knowledge-representation framework that can be used to solve problems declaratively based on abductive reasoning. It extends normal logic programming by allowing some predicates to be incompletely defined, declared as abducible predicates. Problem solving is effected by deriving hypotheses on these abducible predicates (abductive hypotheses) as solutions of problems to be solved. These problems can be either observations that need to be explained (as in classical abduction) or goals to be achieved (as in normal logic programming). It can be used to solve problems in diagnosis, planning, natural language and machine learning. It has also been used to interpret negation as failure as a form of abductive reasoning.