A diacritic is a glyph added to a letter or to a basic glyph. The term derives from the Ancient Greek διακριτικός, from διακρίνω. The word diacritic is a noun, though it is sometimes used in an attributive sense, whereas diacritical is only an adjective. Some diacritics, such as the acute ⟨ó⟩, grave ⟨ò⟩, and circumflex ⟨ô⟩, are often called accents. Diacritics may appear above or below a letter or in some other position such as within the letter or between two letters.
In organic chemistry, ethers are a class of compounds that contain an ether group—an oxygen atom bonded to two organyl groups. They have the general formula R−O−R′, where R and R′ represent the organyl groups. Ethers can again be classified into two varieties: if the organyl groups are the same on both sides of the oxygen atom, then it is a simple or symmetrical ether, whereas if they are different, the ethers are called mixed or unsymmetrical ethers. A typical example of the first group is the solvent and anaesthetic diethyl ether, commonly referred to simply as "ether". Ethers are common in organic chemistry and even more prevalent in biochemistry, as they are common linkages in carbohydrates and lignin.
In chemistry, an ester is a functional group derived from an acid in which the hydrogen atom (H) of at least one acidic hydroxyl group of that acid is replaced by an organyl group. Analogues derived from oxygen replaced by other chalcogens belong to the ester category as well. According to some authors, organyl derivatives of acidic hydrogen of other acids are esters as well, but not according to the IUPAC.
Oxygen is a chemical element; it has symbol O and atomic number 8. It is a member of the chalcogen group in the periodic table, a highly reactive nonmetal, and an oxidizing agent that readily forms oxides with most elements as well as with other compounds. Oxygen is the most abundant element in Earth's crust, and after hydrogen and helium, it is the third-most abundant element in the universe. At standard temperature and pressure, two atoms of the element bind to form dioxygen, a colorless and odorless diatomic gas with the formula O
2. Diatomic oxygen gas currently constitutes 20.95% of the Earth's atmosphere, though this has changed considerably over long periods of time. Oxygen makes up almost half of the Earth's crust in the form of oxides.
O, or o, is the fifteenth letter and the fourth vowel letter of the Latin alphabet, used in the modern English alphabet, the alphabets of other western European languages and others worldwide. Its name in English is o, plural oes.
"O Canada" is the national anthem of Canada. The song was originally commissioned by Lieutenant Governor of Quebec Théodore Robitaille for the 1880 Saint-Jean-Baptiste Day ceremony; Calixa Lavallée composed the music, after which French-language words were written by the poet and judge Sir Adolphe-Basile Routhier.
The Romance languages, also known as the Latin or Neo-Latin languages, are the languages that are directly descended from Vulgar Latin. They are the only extant subgroup of the Italic branch of the Indo-European language family.
The simplified molecular-input line-entry system (SMILES) is a specification in the form of a line notation for describing the structure of chemical species using short ASCII strings. SMILES strings can be imported by most molecule editors for conversion back into two-dimensional drawings or three-dimensional models of the molecules.
Silicon dioxide, also known as silica, is an oxide of silicon with the chemical formula SiO2, commonly found in nature as quartz. In many parts of the world, silica is the major constituent of sand. Silica is one of the most complex and abundant families of materials, existing as a compound of several minerals and as a synthetic product. Examples include fused quartz, fumed silica, opal, and aerogels. It is used in structural materials, microelectronics, and as components in the food and pharmaceutical industries. All forms are white or colorless, although impure samples can be colored.
Big O notation is a mathematical notation that describes the limiting behavior of a function when the argument tends towards a particular value or infinity. Big O is a member of a family of notations invented by German mathematicians Paul Bachmann, Edmund Landau, and others, collectively called Bachmann–Landau notation or asymptotic notation. The letter O was chosen by Bachmann to stand for Ordnung, meaning the order of approximation.
A triglyceride is an ester derived from glycerol and three fatty acids. Triglycerides are the main constituents of body fat in humans and other vertebrates, as well as vegetable fat. They are also present in the blood to enable the bidirectional transference of adipose fat and blood glucose from the liver, and are a major component of human skin oils.
A pika is a small, mountain-dwelling mammal native to Asia and North America. With short limbs, a very round body, an even coat of fur, and no external tail, they resemble their close relative, the rabbit, but with short, rounded ears. The large-eared pika of the Himalayas and nearby mountains lives at elevations of more than 6,000 m (20,000 ft).
India Today is a weekly Indian English-language news magazine published by Living Media India Limited. It is the most widely circulated magazine in India, with a readership of close to 8 million. In 2014, India Today launched a new online opinion-orientated site called the DailyO.
On January 28, 1986, the Space Shuttle Challenger broke apart 73 seconds into its flight, killing all seven crew members aboard. The spacecraft disintegrated 46,000 feet (14 km) above the Atlantic Ocean, off the coast of Cape Canaveral, Florida, at 11:39 a.m. EST. It was the first fatal accident involving an American spacecraft while in flight.
In theoretical computer science, the time complexity is the computational complexity that describes the amount of computer time it takes to run an algorithm. Time complexity is commonly estimated by counting the number of elementary operations performed by the algorithm, supposing that each elementary operation takes a fixed amount of time to perform. Thus, the amount of time taken and the number of elementary operations performed by the algorithm are taken to be related by a constant factor.
In the United States Navy, officers have various ranks. Equivalency between services is by pay grade. United States Navy commissioned officer ranks have two distinct sets of rank insignia: On dress uniform a series of stripes similar to Commonwealth naval ranks are worn; on service khaki, working uniforms, and special uniform situations, the rank insignia are identical to the equivalent rank in the US Marine Corps.
Irish people are an ethnic group and nation native to the island of Ireland, who share a common ancestry, history and culture. There have been humans in Ireland for about 33,000 years, and it has been continually inhabited for more than 10,000 years. For most of Ireland's recorded history, the Irish have been primarily a Gaelic people. From the 9th century, small numbers of Vikings settled in Ireland, becoming the Norse-Gaels. Anglo-Normans also conquered parts of Ireland in the 12th century, while England's 16th/17th century conquest and colonisation of Ireland brought many English and Lowland Scots to parts of the island, especially the north. Today, Ireland is made up of the Republic of Ireland and Northern Ireland. The people of Northern Ireland hold various national identities including British, Irish, Northern Irish or some combination thereof.
O-Town is an American boy band formed from the first season of the reality television series Making the Band in 2000. As of 2015, the group consists of Erik-Michael Estrada, Trevor Penick, Jacob Underwood, and Dan Miller. The original line up included Ashley Parker Angel and Ikaika Kahoano, who was replaced by Miller after dropping out of the group.
The USA Basketball Women's National Team, commonly known as Team USA, is governed by USA Basketball and competes in FIBA Americas. The team is by far the most successful in international women's basketball, having won nine out of the eleven Olympic tournaments it had entered. It has also won nine of the last twelve World Cups, and eleven titles overall. The team is currently ranked first in the FIBA World Rankings.
Stephen Gilchrist Glover, known professionally as Steve-O, is an American entertainer. His career is mostly centered on his shocking and pain-inducing stunts in the reality comedy television series Jackass (2000–2001) and its related films Jackass: The Movie (2002), Jackass Number Two (2006), Jackass 3D (2010), and Jackass Forever (2022), as well as its spin-off series Wildboyz (2003–2006) and Dr. Steve-O (2007).
