Vietnam deleted the rule that made its ID numbers decodable, and nobody stopped decoding them
Since 1 July 2024 no Vietnamese instrument says the 12-digit citizen ID has any internal structure. The decree defining...
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The calcium formula everyone uses is not the one it cites
Corrected calcium is computed with a coefficient of 0.8 and attributed to Payne 1973 on virtually every clinical referen...
Half the pronunciation changes people argued about had already happened
The viral lists of Chinese readings the ministry supposedly changed trace to a 2016 draft that was never issued. But the...
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Taiwan's passport rules name no romanisation system at all
The received account is that Taiwan uses Wade-Giles, or 通用拼音, or has moved to Hanyu Pinyin. Article 14 of the passpo...
Your CO2 monitor's red line is a 19th-century number, and it is drifting
The 1000 ppm line is Pettenkofer's, proposed in the 19th century as a proxy for whether a room smelled stuffy. ASHRAE re...
Two poison services disagree about how much chocolate your dog can eat
Britain's Veterinary Poisons Information Service answers in grams of chocolate per kilo of dog. The ASPCA and Merck line...
Leap seconds end on 20 May 2027, and the Earth has already turned around
The committee that has inserted 27 leap seconds since 1972 is proposing to stop, and to let clock time drift up to an ho...
The South Asian number ladder that no two countries share
Lakh and crore are usually presented as one regional system continuing upward into arab and kharab. Take the ladder to f...
The kidney formula in your drug label came from seven data points
The 1976 equation that still decides anticoagulant doses was fitted to seven averaged points, drawn from 249 men after h...
The letter Chinese passports will not print
Hanyu Pinyin has a letter no Chinese travel document will print: ü. The rule that replaces it is two rules, not one — 吕...
The 226-page book that decides how Macau spells your name
Macau has a statutory table for romanising Cantonese names, running 226 pages of the 1985 gazette. Hong Kong has no rule...
The Chinese festivals that are set by the sun, not the moon
Most Chinese festivals fall on a lunar date, and two of the best known do not. Qingming and the Winter Solstice are fixe...
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