Astrolabes, sundials, and astronomical clocks sometimes show the hour length and count using some of these older definitions and counting methods. Counting from dawn
In ancient and medieval cultures, the counting of hours generally started with sunrise. Before the widespread use of artificial light, societies were more concerned with the division between night and day, and daily routines often began when light was sufficient. "Babylonian hours" divide the day and night into 24 equal hours, reckoned from the time of sunrise. They are so named from the false belief of ancient authors that the Babylonians divided the day into 24 parts, beginning at sunrise. In fact, they divided the day into 12 parts (called kaspu or "double hours") or into 60 equal parts. Unequal hours
Sunrise marked the beginning of the first hour, the middle of the day was at the end of the sixth hour and sunset at the end of the twelfth hour. This meant that the duration of hours varied with the season. In the Northern hemisphere, particularly in the more northerly latitudes, summer daytime hours were longer than winter daytime hours, each being one twelfth of the time between sunrise and sunset. These variable-length hours were variously known as temporal, unequal, or seasonal hours and were in use until the appearance of the mechanical clock, which furthered the adoption of equal length hours.This is also the system used in Jewish law and frequently called "Talmudic hour" (Shaa Zemanit) in a variety of texts.
Society and culture
Naming
Paracetamol is the Australian Approved Name and British Approved Name as well as the international nonproprietary name used by the WHO and in many other countries; acetaminophen is the United States Adopted Name and Japanese Accepted Name and also the name generally used in Canada, Venezuela, Colombia, and Iran. Both paracetamol and acetaminophen are contractions of para-acetylaminophenol, a chemical name for the compound. The initialism APAP used by dispensing pharmacists in the United States comes from the alternative chemical name [N-]acetyl-para-aminophenol. Available forms
Paracetamol is available in oral, suppository, and intravenous forms. Intravenous paracetamol is sold under the brand name Ofirmev in the United States.In some formulations, paracetamol is combined with the opiate codeine, sometimes referred to as co-codamol (BAN) and Panadeine in Australia. In the US, this combination is available only by prescription. As of 1 February 2018, medications containing codeine also became prescription-only in Australia. Paracetamol is also combined with other opioids such as dihydrocodeine, referred to as co-dydramol (British Approved Name (BAN)), oxycodone or hydrocodone. Another very commonly used analgesic combination includes paracetamol in combination with propoxyphene napsylate. A combination of paracetamol, codeine, and the doxylamine succinate is also available.Paracetamol is sometimes combined with phenylephrine hydrochloride. Sometimes a third active ingredient, such as ascorbic acid, caffeine, chlorpheniramine maleate, or guaifenesin is added to this combination. Veterinary use
Cats
Paracetamol is extremely toxic to cats, which lack the necessary UGT1A6 enzyme to detoxify it. Initial symptoms include vomiting, salivation, and discoloration of the tongue and gums.