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Paracetamol (acetaminophen[a]) is a non-opioid analgesic and antipyretic agent used to treat fever and mild to moderate pain.[13][14][15] It is a widely used over the counter medication. Common brand names include Tylenol and Panadol. At a standard dose, paracetamol only slightly reduces fever;[14][16][17] it is inferior to ibuprofen in that ...
Tramadol, sold under the brand name Ultram among others,[1] is an opioid pain medication and a serotonin–norepinephrine reuptake inhibitor (SNRI) used to treat moderately severe pain.[3][14] When taken by mouth in an immediate-release formulation, the onset of pain relief usually begins within an hour.[3] It is also available by injection ...
The Beulé Gate is a fortified gate leading to the Propylaia of the Acropolis of Athens, Greece.It was constructed largely of repurposed material taken from the 4th-century BCE Choragic Monument of Nikias and integrated into the Post-Herulian Wall, a late Roman fortification built around the Acropolis in the years following the city's sack by the Germanic Heruli people in 267 or early 268 CE.
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The word zero came into the English language via French zéro from the Italian zero, a contraction of the Venetian zevero form of Italian zefiro via ṣafira or ṣifr. In pre-Islamic time the word ṣifr (Arabic صفر) had the meaning "empty". Sifr evolved to mean zero when it was used to translate śūnya (Sanskrit: शून्य) from India. The first known Englis...
Ancient Near East
Ancient Egyptian numerals were of base 10. They used hieroglyphs for the digits and were not positional. In one papyrus written around 1770 BC, a scribe recorded daily incomes and expenditures for the pharaoh's court, using the nfr hieroglyph to indicate cases where the amount of a foodstuff received was exactly equal to the amount disbursed. Egyptologist Alan Gardiner suggested that the nfrhieroglyph was being used as a symbol for zero. The same symbol was also used to indicate the base leve...
Pre-Columbian Americas
The Mesoamerican Long Count calendar developed in south-central Mexico and Central America required the use of zero as a placeholder within its vigesimal (base-20) positional numeral system. Many different glyphs, including the partial quatrefoil were used as a zero symbol for these Long Count dates, the earliest of which (on Stela 2 at Chiapa de Corzo, Chiapas) has a date of 36 BC.[a] Since the eight earliest Long Count dates appear outside the Maya homeland, it is generally believed that th...
Classical antiquity
The ancient Greeks had no symbol for zero (μηδέν, pronounced 'midén'), and did not use a digit placeholder for it. According to mathematician Charles Seife, the ancient Greeks did begin to adopt the Babylonian placeholder zero for their work in astronomy after 500 BC, representing it with the lowercase Greek letter ό (όμικρον: omicron). However, after using the Babylonian placeholder zero for astronomical calculations they would typically convert the numbers back into Greek numerals. Greeks s...
Today, the numerical digit 0 is usually written as a circle or ellipse. Traditionally, many print typefaces made the capital letter O more rounded than the narrower, elliptical digit 0. Typewriters originally made no distinction in shape between O and 0; some models did not even have a separate key for the digit 0. The distinction came into promine...
The concept of zero plays multiple roles in mathematics: as a digit, it is an important part of positional notation for representing numbers, while it also plays an important role as a number in its own right in many algebraic settings.
The value zero plays a special role for many physical quantities. For some quantities, the zero level is naturally distinguished from all other levels, whereas for others it is more or less arbitrarily chosen. For example, for an absolute temperature (typically measured in kelvins), zero is the lowest possible value. (Negative temperatures can be d...
Modern computers store information in binary, that is, using an "alphabet" that contains only two symbols, usually chosen to be "0" and "1". Binary coding is convenient for digital electronics, where "0" and "1" can stand for the absence or presence of electrical current in a wire. Computer programmers typically use high-level programming languages...
Biology
In comparative zoology and cognitive science, recognition that some animals display awareness of the concept of zero leads to the conclusion that the capability for numerical abstraction arose early in the evolutionof species.
Dating systems
In the BC calendar era, the year 1BC is the first year before AD1; there is not a year zero. By contrast, in astronomical year numbering, the year 1BC is numbered 0, the year 2BC is numbered −1, and so forth.
Wikipedia is a free online encyclopedia that anyone can edit, and millions already have . Wikipedia's purpose is to benefit readers by presenting information on all branches of knowledge. Hosted by the Wikimedia Foundation, it consists of freely editable content, whose articles also have numerous links to guide readers towards more information.
Germany,[e] officially the Federal Republic of Germany,[f] is a country in the western region of Central Europe. It is the second-most populous country in Europe after Russia[g] and the most populous member state of the European Union. Germany lies between the Baltic and North Sea to the north and the Alps to the south. Its 16 constituent ...
Sweden,[f] formally the Kingdom of Sweden,[g][h] is a Nordic country located on the Scandinavian Peninsula in Northern Europe. At 450,295 square kilometres (173,860 sq mi),[10] Sweden is the largest Nordic country and the fifth-largest country in Europe. The capital and largest city is Stockholm. Sweden has a population of 10.5 million,[6] and ...
