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Hypertension, also known as high blood pressure, is a long-term medical condition in which the blood pressure in the arteries is persistently elevated. High blood pressure usually does not cause symptoms itself. It is, however, a major risk factor for stroke, coronary artery disease, heart failure, atrial fibrillation, peripheral arterial disease, vision loss, chronic kidney disease, and dementia.
550 Madison Avenue is a postmodern skyscraper on Madison Avenue between 55th Street and 56th Street in New York City. Designed by Philip Johnson and John Burgee with associate architect Simmons Architects, the building was completed in 1984. It is a 647-foot-tall (197-meter), 37-story office tower with a facade made of pink granite.
0.8–1.5% (2019, using DSM-IV-TR and ICD-10) [2] Attention deficit hyperactivity disorder ( ADHD) is a neurodevelopmental disorder characterised by executive dysfunction occasioning symptoms of inattention, hyperactivity, impulsivity and emotional dysregulation that are excessive and pervasive, impairing in multiple contexts, and otherwise age ...
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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.
Umami (/ uː ˈ m ɑː m i / from Japanese: 旨味 Japanese pronunciation:), or savoriness, is one of the five basic tastes. It has been described as savory and is characteristic of broths and cooked meats.: 35–36 People taste umami through taste receptors that typically respond to glutamates and nucleotides, which are widely present in meat broths and fermented products.
salamu alaykum written in the Thuluth style of Arabic calligraphy As-salamu alaykum (Arabic: ٱلس ل ام ع ل ي ك م , as-salāmu ʿalaykum, Arabic: [as.sa.laː.mu ʕa.laj.kum] ), also written salamun alaykum and typically rendered in English as salam alaykum, is a greeting in Arabic that means 'Peace be upon you'. '. The salām (س ل ام, meaning 'peace') has become a religious ...
Capsaicin (8-methyl-N-vanillyl-6-nonenamide) (/ k æ p ˈ s eɪ s ɪ n / or / k æ p ˈ s eɪ ə s ɪ n /) is an active component of chili peppers, which are plants belonging to the genus Capsicum.It is a chemical irritant and neurotoxin for mammals, including humans, and produces a sensation of burning in any tissue with which it comes into contact. . Capsaicin and several related amides ...
