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# Amstrad CPC
## Models
### Special models and clones {#special_models_and_clones}
#### CPC 472 {#cpc_472}
During the August holidays of 1985, Spain briefly introduced an import tax of 15 000 pesetas ({{€\|90.15}}) on computers containing 64 KB or less of RAM (Royal Decree 1215/1985 and 1558/1985), and a new law (Royal Decree 1250/1985) mandated that all computers sold in Spain must have a Spanish keyboard. To circumvent this, Amstrad\'s Spanish distributor *Indescomp* (later to become *Amstrad Spain*) created and distributed the *CPC 472*, a modified version of the CPC 464. Its main differences are a small additional daughter board containing a CPC 664 ROM chip and an 8 KB memory chip, and a keyboard with a ñ key (although some of them were temporarily manufactured without the ñ key). The sole purpose of the 8 KB memory chip (which is not electrically connected to the machine, so consequently rendered unusable) is to increase the machine\'s total memory specs to 72 KB in order to circumvent the import tax. Some months later, Spain joined the European Communities by the Treaty of Accession 1985 and the import tax was suppressed, so Amstrad added the ñ key for the 464 and production of the CPC 472 was discontinued.`{{better source needed|date=September 2020}}`{=mediawiki}
#### KC compact {#kc_compact}
The *`{{Interlanguage link multi|KC compact|de}}`{=mediawiki}* (\"*Kleincomputer*\" - which means \"small computer\" - being a rather literal German translation of the English \"microcomputer\") is a clone of the Amstrad CPC built by East Germany\'s **VEB\]\] Mikroelektronik Mühlhausen**, part of **VEB \[\[Kombinat Mikroelektronik Erfurt\]\]**, in October 1989. Although the machine included various substitutes and emulations of an Amstrad CPC\'s hardware, the machine is largely compatible with Amstrad CPC software. It is equipped with 64 KB of memory and a CPC 6128\'s firmware customized to the modified hardware, including a copy of Locomotive BASIC 1.1 modified in the startup banner only. The expansion port is a K 1520 bus slot. The KC compact is the last 8-bit computer introduced in East Germany. Due to the German reunification happening at the time of the release, only a very small number of systems were sold. The KC compact can be emulated by free software *JKCEMU*.
#### Aleste 520EX {#aleste_520ex}
In 1993, Omsk, Russia based company Patisonic released the Aleste 520EX, a computer highly compatible with the Amstrad CPC 6128. It could also be switched into an MSX mode. An expansion board named *Magic Sound* allowed to play Scream Tracker files.
## Reception
*Your Computer* concluded that the CPC 464 had \"Superior graphics and sound, an excellent Basic coupled with a flexible operating system\" and that Amstrad\'s target sales of 200,000 by the end of 1984 were realistic.
A *BYTE* columnist in January 1985 called the CPC 464 \"the closest yet to filling\" his criteria for a useful home computer, including good keyboard, 80-column text, inexpensive disk drive, and support for a mainstream operating system like CP/M.
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# Amstrad CPC
## Hardware
### Processor
The entire CPC series is based on the Zilog Z80; a processor, clocked at 4 MHz. In order to avoid the CPU and the video logic simultaneously accessing the shared main memory and causing video corruption (\"snowing\"), CPU memory access is constrained to occur on microsecond boundaries. This effectively pads every machine cycle to four clock cycles, causing a minor loss of processing power and resulting in what Amstrad estimated to be an \"effective clock rate\" of \"approximately 3.3 MHz\".
### Memory
Amstrad CPCs are equipped with either 64 (CPC 464, CPC 664, 464plus, GX4000) or 128 (CPC 6128, 6128plus) KB of RAM. This base memory can be extended by up to 512 KB using memory expansions sold by third-party manufacturers, and by up to 4096 KB using experimental methods developed by hardware enthusiasts. Because the Z80 processor is only able to directly address 64 KB of memory, additional memory from the 128 KB models and memory expansions is made available using bank switching.
### Video
Underlying a CPC\'s video output is the unusual pairing of a CRTC (Motorola 6845 or compatible) with a custom-designed gate array to generate a pixel display output. CPC 6128s later in production as well as the models from the plus range integrate both the CRTC and the gate array\'s functions with the system\'s ASIC.
Three built-in display resolutions are available: 160×200 pixels with 16 colours (\"Mode 0\", 20 text columns), 320×200 pixels with 4 colours (\"Mode 1\", 40 text columns), and 640×200 pixels with 2 colours (\"Mode 2\", 80 text columns). Increased screen size can be achieved by reprogramming the CRTC.
The original CPC video hardware supports a colour palette of 27 colours, generated from RGB colour space with each colour component assigned as either off, half on, or on (3 level RGB palette). The plus range extended the palette to 4096 colours, also generated from RGB with 4 bits each for red, green and blue (12-bit RGB).
With the exception of the GX4000, all CPC models lack an RF television or composite video output and instead shipped with a 6-pin RGB DIN connector, also used by Acorn computers, to connect the supplied Amstrad monitor. This connector delivers a 1v p-p analogue RGB with a 50 Hz composite sync signal that, if wired correctly, can drive a 50 Hz SCART television. External adapters for RF television were available as a first-party hardware accessory.
### Audio
The CPC uses the General Instrument AY-3-8912 sound chip, providing three channels, each configurable to generate square waves, white noise or both. A small array of hardware volume envelopes are available.
Output is provided in mono by a small (4 cm) built-in loudspeaker with volume control, driven by an internal amplifier. Stereo output is provided through a `{{nowrap|3.5 mm}}`{=mediawiki} headphones jack.
It is possible to play back digital sound samples at a resolution of approximately 5-bit by sending a stream of values to the sound chip. This technique is very processor-intensive and hard to combine with any other processing. Examples are the title screens or other non-playable scenes of games like *Chase H.Q.*, *Meltdown*, and *RoboCop*. The later Plus models incorporated a DMA engine in order to offload this processing.
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# Amstrad CPC
## Hardware
### Floppy disk drive {#floppy_disk_drive}
Amstrad uses Matsushita\'s 3\" floppy disk drive \[ref: CPCWiki\], which was compatible with Hitachi\'s existing 3\" floppy disk format. The chosen drive (built-in for later models) is a single-sided 40-track unit that requires the user to remove and flip the disk to access the other side. Each side has its own independent write-protect switch. The sides are termed \"A\" and \"B\", with each one commonly formatted to 180 KB (in AMSDOS format, comprising 2 KB directory and 178 KB storage) for a total of 360 KB per disk.
The interface with the drives is an NEC 765 FDC, used for the same purpose in the IBM PC/XT, PC/AT and PS/2 machines. Its features are not fully used in order to cut costs, namely DMA transfers and support for single density disks; they were formatted as double density using modified frequency modulation.
Discs were shipped in a paper sleeve or a hard plastic case resembling a compact disc \"jewel\" case. The casing is thicker and more rigid than that of 3.5 inch diskettes, and designed to be mailed without any additional packaging. A sliding metal cover to protect the media surface is internal to the casing and latched, unlike the simple external sliding cover of Sony\'s version. They were significantly more expensive than both 5.25 inch and 3.5 inch alternatives. This, combined with their low nominal capacities and their essentially proprietary nature, led to the format being discontinued shortly after the CPC itself was discontinued.
Apart from Amstrad\'s other 3-inch machines (the PCW and the ZX Spectrum +3), the few other computer systems to use them included the Sega SF-7000 and CP/M systems such as the Tatung Einstein and Osborne machines. They also found use on embedded systems.
The Shugart-standard interface means that Amstrad CPC machines are able to use standard 3\", 3½\" or 5¼\" drives as their second drive. Programs such as ROMDOS and ParaDOS extend the standard AMSDOS system to provide support for double-sided, 80-track formats, enabling up to 800 KB to be stored on a single disk.
The 3-inch disks themselves are usually known as \"discs\" on the CPC, following the spelling on the machine\'s plastic casing and conventional British English spelling.
### Expansion
The hardware and firmware was designed to be able to access software provided on external ROMs. Each ROM has to be a 16 KB block and is switched in and out of the memory space shared with the video RAM. The Amstrad firmware is deliberately designed so that new software could be easily accessed from these ROMs. Popular applications were marketed on ROM, particularly word processing and programming utility software (examples are Protext and Brunword of the former, and the MAXAM assembler of the latter type).
Such extra ROM chips do not plug directly into the CPC itself, but into extra plug-in \"rom boxes\" which contain sockets for the ROM chips and a minimal amount of decoding circuitry for the main machine to be able to switch between them. These boxes were either marketed commercially or could be built by competent hobbyists and they attached to the main expansion port at the back of the machine. Software on ROM loads much faster than from disc or tape and the machine\'s boot-up sequence was designed to evaluate ROMs it found and optionally hand over control of the machine to them. This allows significant customisation of the functionality of the machine, something that enthusiasts exploited for various purposes. However, the typical users would probably not be aware of this added ROM functionality unless they read the CPC press, as it is not described in the user manual and was hardly ever mentioned in marketing literature. It is, however, documented in the official Amstrad firmware manual.
The machines also feature a 9-pin Atari joystick port that will either directly take one joystick, or two joysticks by use of a splitter cable.
## Peripherals
### RS232 serial adapters {#rs232_serial_adapters}
Amstrad issued two RS-232-C D25 serial interfaces, attached to the expansion connector on the rear of the machine, with a through-connector for the CPC 464 disk drive or other peripherals.
The original interface came with a *Book of Spells* for facilitating data transfer between other systems using a proprietary protocol in the device\'s own ROM, as well as terminal software to connect to British Telecom\'s Prestel service. A separate version of the ROM was created for the U.S. market due to the use of the commands \"\|SUCK\" and \"\|BLOW\", which were considered unacceptable there.
Software and hardware limitations in this interface led to its replacement with an Amstrad-branded version of a compatible alternative by Pace. Serial interfaces were also available from third-party vendors such as KDS Electronics and Cirkit.
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# Amstrad CPC
## Software
### BASIC and operating system {#basic_and_operating_system}
Like most home computers at the time, the CPC has its OS and a BASIC interpreter built in as ROM. It uses Locomotive BASIC - an improved version of Locomotive Software\'s Z80 BASIC for the BBC Micro co-processor board. It is particularly notable for providing easy access to the machine\'s video and audio resources in contrast to the POKE commands required on generic Microsoft implementations. Other unusual features include timed event handling with the AFTER and EVERY commands, and text-based windowing.
### CP/M
Digital Research\'s CP/M operating system was supplied with the 664 and 6128 disk-based systems, and the DDI-1 disk expansion unit for the 464. 64k machines shipped with CP/M 2.2 alone, while the 128k machines also include CP/M 3.1. The compact CP/M 2.2 implementation is largely stored on the boot sectors of a 3\" disk in what was called \"System format\"; typing \|CPM from Locomotive BASIC would load code from these sectors, making it a popular choice for custom game loading routines. The CP/M 3.1 implementation is largely in a separate file which is in turn loaded from the boot sector. Much public domain CP/M software was made available for the CPC, from word-processors such as VDE to complete bulletin board systems such as ROS.
### Other languages {#other_languages}
Although it was possible to obtain compilers for Locomotive BASIC, C and Pascal, the majority of the CPC\'s software was written in native Z80 assembly language. Popular assemblers were Hisoft\'s Devpac, Arnor\'s Maxam, and (in France) DAMS. Disk-based CPC (not Plus) systems shipped with an interpreter for the educational language LOGO, booted from CP/M 2.2 but largely CPC-specific with much code resident in the AMSDOS ROM; 6128 machines also include a CP/M 3.1, non-ROM version. A C compiler was also written and made available for the European market through Tandy Europe, by Micro Business products.
### *Roland*
In an attempt to give the CPC a recognisable mascot, a number of games by Amstrad\'s in-house software publisher Amsoft have been tagged with the *Roland* name. However, as the games had not been designed around the Roland character and only had the branding added later, the character design varies immensely, from a spiky-haired blonde teenager (*Roland Goes Digging*) to a white cube with legs (*Roland Goes Square Bashing*) or a mutant flea (*Roland in the Caves*). The only two games with similar gameplay and main character design are *Roland in Time* and its sequel *Roland in Space*. The Roland character was named after Roland Perry, one of the lead designers of the original CPC range.
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# Amstrad CPC
## Schneider Computer Division {#schneider_computer_division}
In order to market its computers in Germany, Austria, and Switzerland where Amstrad did not have any distribution structures, Amstrad entered a partnership with *Schneider Rundfunkwerke AG*, a German company that - very much like Amstrad itself - was previously only known for value-priced audio products. In 1984, Schneider\'s *Schneider Computer Division* daughter company was created specifically for the task, and the complete Amstrad CPC line-up was branded and sold as *Schneider CPC*.
Although they are based on the same hardware, the Schneider CPC models differ from the Amstrad CPC models in several details. Most prominently, the Schneider CPC 464 and CPC 664 keyboards featured grey instead of coloured keys, but still in the original British keyboard layout. To achieve a German \"QWERTZ\" keyboard layout, Schneider marketed a small software program to reassign the keys as well as sticker labels for the keys. In order to conform with stricter German EMC regulations, the complete Schneider CPC line-up is equipped with an internal metal shielding. For the same reason, the Schneider CPC 6128 features micro ribbon type connectors instead of edge connectors. Both the greyscale keyboard and the micro ribbon connectors found their way up into the design of later Amstrad CPC models.
In 1988, after Schneider refused to market Amstrad\'s AT-compatible computer line, the cooperation ended. Schneider went on to sell the remaining stock of Schneider CPC models and used their now well-established market position to introduce its own PC designs. With the formation of its German daughter company *Amstrad GmbH* to distribute its product lines including the CPC 464 and CPC 6128, Amstrad attempted but ultimately failed to establish their own brand in the German-speaking parts of Europe.
## Community
The Amstrad CPC enjoyed a strong and long lifetime, mainly due to the machines use for businesses as well as gaming. Dedicated programmers continued working on the CPC range, even producing graphical user interface (GUI) operating systems such as SymbOS. Internet sites devoted to the CPC have appeared from around the world featuring forums, news, hardware, software, programming and games. CPC Magazines appeared during the 1980s including publications in countries such as Britain, France, Spain, Germany, Denmark, Australia, and Greece. Titles included the official Amstrad Computer User publication, as well as independent titles like *Amstrad Action*, *Amtix!*, *Computing with the Amstrad CPC*, *CPC Attack*, Australia\'s *The Amstrad User*, France\'s *Amstrad Cent Pour Cent* and *Amstar*. Following the CPC\'s end of production, Amstrad gave permission for the CPC ROMs to be distributed freely as long as the copyright message is not changed and that it is acknowledged that Amstrad still holds copyright, giving emulator authors the possibility to ship the CPC firmware with their programs.
## Influence on other Amstrad machines {#influence_on_other_amstrad_machines}
Amstrad followed their success with the CPC 464 by launching the Amstrad PCW word-processor range, another Z80-based machine with a 3\" disk drive and software by Locomotive Software. The PCW was originally developed to be partly compatible with an improved version of the CPC (*ANT*, or Arnold Number Two - the CPC\'s development codename was Arnold). However, Amstrad decided to focus on the PCW, and the ANT project never came to market.
On 7 April 1986, Amstrad announced it had bought from Sinclair Research \"\...the worldwide rights to sell and manufacture all existing and future Sinclair computers and computer products, together with the Sinclair brand name and those intellectual property rights where they relate to computers and computer-related products.\" which included the ZX Spectrum, for £5 million. This included Sinclair\'s unsold stock of Sinclair QLs and Spectrums. Amstrad made more than £5 million on selling these surplus machines alone. Amstrad launched two new variants of the Spectrum: the ZX Spectrum +2, based on the ZX Spectrum 128, with a built-in tape drive (like the CPC 464) and, the following year, the ZX Spectrum +3, with a built-in floppy disk drive (similar to the CPC 664 and 6128), taking the 3\" discs that Amstrad CPC machines used
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# Aage Bohr
**Aage Niels Bohr** (`{{IPA|da|ˈɔːwə ˈne̝ls ˈpoɐ̯ˀ|lang|Da-Aage Niels Bohr.ogg}}`{=mediawiki}; 19 June 1922 -- 8 September 2009) was a Danish nuclear physicist who shared the Nobel Prize in Physics in 1975 with Ben Roy Mottelson and James Rainwater \"for the discovery of the connection between collective motion and particle motion in atomic nuclei and the development of the theory of the structure of the atomic nucleus based on this connection\". His father was Niels Bohr.
Starting from Rainwater\'s concept of an irregular-shaped liquid drop model of the nucleus, Bohr and Mottelson developed a detailed theory that was in close agreement with experiments.
Since his father, Niels Bohr, had won the prize in 1922, he and his father are one of the six pairs of fathers and sons who have both won the Nobel Prize and one of the four pairs who have both won the Nobel Prize in Physics.
## Early life and education {#early_life_and_education}
Bohr was born in Copenhagen on 19 June 1922, the fourth of six sons of the physicist Niels Bohr and his wife Margrethe Bohr (née Nørlund). His oldest brother, Christian, died in a boating accident in 1934, and his youngest, Harald, was severely disabled and placed away from the home in Copenhagen at the age of four. He would later die from childhood meningitis. Of the others, Hans became a physician; Erik, a chemical engineer; and Ernest, a lawyer and Olympic athlete who played field hockey for Denmark at the 1948 Summer Olympics in London. The family lived at the Institute of Theoretical Physics at the University of Copenhagen, now known as the Niels Bohr Institute, where he grew up surrounded by physicists who were working with his father, such as Hans Kramers, Oskar Klein, Yoshio Nishina, Wolfgang Pauli and Werner Heisenberg. In 1932, the family moved to the Carlsberg Æresbolig, a mansion donated by Carl Jacobsen, the heir to Carlsberg breweries, to be used as an honorary residence by the Dane who had made the most prominent contribution to science, literature, or the arts.
Bohr went to high school at Sortedam Gymnasium in Copenhagen. In 1940, shortly after the German occupation of Denmark in April, he entered the University of Copenhagen, where he studied physics. He assisted his father, helping draft correspondence and articles related to epistemology and physics. In September 1943, word reached his family that the Nazis considered them to be Jewish, because Bohr\'s grandmother, Ellen Adler Bohr, had been Jewish, and that they therefore were in danger of being arrested. The Danish resistance helped the family escape by sea to Sweden. Bohr arrived there in October 1943, and then flew to Britain on a de Havilland Mosquito operated by British Overseas Airways Corporation. The Mosquitoes were unarmed high-speed bomber aircraft that had been converted to carry small, valuable cargoes or important passengers. By flying at high speed and high altitude, they could cross German-occupied Norway, and yet avoid German fighters. Bohr, equipped with parachute, flying suit and oxygen mask, spent the three-hour flight lying on a mattress in the aircraft\'s bomb bay.
On arrival in London, Bohr rejoined his father, who had flown to Britain the week before. He officially became a junior researcher at the Department of Scientific and Industrial Research, but actually served as personal assistant and secretary to his father. The two worked on Tube Alloys, the British atomic bomb project. On 30 December 1943, they made the first of a number of visits to the United States, where his father was a consultant to the Manhattan Project. Due to his father\'s fame, they were given false names; Bohr became James Baker, and his father, Nicholas Baker. In 1945, the director of the Los Alamos Laboratory, J. Robert Oppenheimer, asked them to review the design of the modulated neutron initiator. They reported that it would work. That they had reached this conclusion put Enrico Fermi\'s concerns about the viability of the design to rest. The initiators performed flawlessly in the bombs used in the atomic bombings of Hiroshima and Nagasaki in August 1945.
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# Aage Bohr
## Career
In August 1945, with the war ended, Bohr returned to Denmark, where he resumed his university education, graduating with a master\'s degree in 1946, with a thesis concerned with some aspects of atomic stopping power problems. In early 1948, Bohr became a member of the Institute for Advanced Study in Princeton, New Jersey. While paying a visit to Columbia University, he met Isidor Isaac Rabi, who sparked in him an interest in recent discoveries related to the hyperfine structure of deuterium. This led to Bohr becoming a visiting fellow at Columbia from January 1949 to August 1950. While in the United States, Bohr married Marietta Soffer on 11 March 1950. They had three children: Vilhelm, Tomas and Margrethe.
By the late 1940s it was known that the properties of atomic nuclei could not be explained by then-current models such as the liquid drop model developed by Niels Bohr amongst others. The shell model, developed in 1949 by Maria Goeppert Mayer and others, allowed some additional features to be explained, in particular the so-called magic numbers. However, there were also properties that could not be explained, including the non-spherical distribution of charge in certain nuclei. In a 1950 paper, James Rainwater of Columbia University suggested a variant of the drop model of the nucleus that could explain a non-spherical charge distribution. Rainwater\'s model postulated a nucleus like a balloon with balls inside that distort the surface as they move about. He discussed the idea with Bohr, who was visiting Columbia at the time, and had independently conceived the same idea, and had, about a month after Rainwater\'s submission, submitted for publication a paper that discussed the same problem, but along more general lines. Bohr imagined a rotating, irregular-shaped nucleus with a form of surface tension. Bohr developed the idea further, in 1951 publishing a paper that comprehensively treated the relationship between oscillations of the surface of the nucleus and the movement of the individual nucleons.
Upon his return to Copenhagen in 1950, Bohr began working with Ben Roy Mottelson to compare the theoretical work with experimental data. In three papers, that were published in 1952 and 1953, Bohr and Mottelson demonstrated close agreement between theory and experiment; for example, showing that the energy levels of certain nuclei could be described by a rotation spectrum. They were thereby able to reconcile the shell model with Rainwater\'s concept. This work stimulated many new theoretical and experimental studies. Bohr, Mottelson and Rainwater were jointly awarded the 1975 Nobel Prize in Physics \"for the discovery of the connection between collective motion and particle motion in atomic nuclei and the development of the theory of the structure of the atomic nucleus based on this connection\". Because his father had been awarded the prize in 1922, Bohr became one of only four pairs of fathers and sons to win the Nobel Prize in Physics.
Only after doing his Nobel Prize-winning research did Bohr receive his doctorate from the University of Copenhagen, in 1954, writing his thesis on \"Rotational States of Atomic Nuclei\". Bohr became a professor at the University of Copenhagen in 1956, and, following his father\'s death in 1962, succeeded him as director of the Niels Bohr Institute, a position he held until 1970. He remained active there until he retired in 1992. He was also a member of the board of the Nordic Institute for Theoretical Physics from its inception in 1957, and was its director from 1975 to 1981. In addition to the Nobel Prize, he won the Dannie Heineman Prize for Mathematical Physics in 1960, the Atoms for Peace Award in 1969, H. C. Ørsted Medal in 1970, Rutherford Medal and Prize in 1972, John Price Wetherill Medal in 1974, and the Ole Rømer medal in 1976. Bohr and Mottelson continued to work together, publishing a two-volume monograph, *Nuclear Structure*. The first volume, *Single-Particle Motion,* appeared in 1969; the second, *Nuclear Deformations,* in 1975.
In 1972 Bohr was awarded an honorary degree, doctor philos. honoris causa, at the Norwegian Institute of Technology, later part of Norwegian University of Science and Technology. He was a member of the Norwegian Academy of Science and Letters from 1980. Bohr was also an elected member of the American Academy of Arts and Sciences, the American Philosophical Society, and the United States National Academy of Sciences.
In 1981, Bohr became a founding member of the World Cultural Council.
Bohr\'s wife Marietta died on 2 October 1978. In 1981, he married Bente Scharff Meyer (1926--2011). His son, Tomas Bohr, is a professor of physics at the Technical University of Denmark, working in the area of fluid dynamics. Aage Bohr died in Copenhagen on 9 September 2009. He was survived by his second wife and children.
Bohr\'s Nobel Prize medal was sold at auction in November 2011. It was subsequently sold at auction in April 2019 for \$90,000
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# Analytic geometry
In mathematics, **analytic geometry**, also known as **coordinate geometry** or **Cartesian geometry**, is the study of geometry using a coordinate system. This contrasts with synthetic geometry.
Analytic geometry is used in physics and engineering, and also in aviation, rocketry, space science, and spaceflight. It is the foundation of most modern fields of geometry, including algebraic, differential, discrete and computational geometry.
Usually the Cartesian coordinate system is applied to manipulate equations for planes, straight lines, and circles, often in two and sometimes three dimensions. Geometrically, one studies the Euclidean plane (two dimensions) and Euclidean space. As taught in school books, analytic geometry can be explained more simply: it is concerned with defining and representing geometric shapes in a numerical way and extracting numerical information from shapes\' numerical definitions and representations. That the algebra of the real numbers can be employed to yield results about the linear continuum of geometry relies on the Cantor--Dedekind axiom.
## History
### Ancient Greece {#ancient_greece}
The Greek mathematician Menaechmus solved problems and proved theorems by using a method that had a strong resemblance to the use of coordinates and it has sometimes been maintained that he had introduced analytic geometry.
Apollonius of Perga, in *On Determinate Section*, dealt with problems in a manner that may be called an analytic geometry of one dimension; with the question of finding points on a line that were in a ratio to the others. Apollonius in the *Conics* further developed a method that is so similar to analytic geometry that his work is sometimes thought to have anticipated the work of Descartes by some 1800 years. His application of reference lines, a diameter and a tangent is essentially no different from our modern use of a coordinate frame, where the distances measured along the diameter from the point of tangency are the abscissas, and the segments parallel to the tangent and intercepted between the axis and the curve are the ordinates. He further developed relations between the abscissas and the corresponding ordinates that are equivalent to rhetorical equations (expressed in words) of curves. However, although Apollonius came close to developing analytic geometry, he did not manage to do so since he did not take into account negative magnitudes and in every case the coordinate system was superimposed upon a given curve *a posteriori* instead of *a priori*. That is, equations were determined by curves, but curves were not determined by equations. Coordinates, variables, and equations were subsidiary notions applied to a specific geometric situation.
### Persia
The 11th-century Persian mathematician Omar Khayyam saw a strong relationship between geometry and algebra and was moving in the right direction when he helped close the gap between numerical and geometric algebra with his geometric solution of the general cubic equations, but the decisive step came later with Descartes. Omar Khayyam is credited with identifying the foundations of algebraic geometry, and his book *Treatise on Demonstrations of Problems of Algebra* (1070), which laid down the principles of analytic geometry, is part of the body of Persian mathematics that was eventually transmitted to Europe. Because of his thoroughgoing geometrical approach to algebraic equations, Khayyam can be considered a precursor to Descartes in the invention of analytic geometry.
### Western Europe {#western_europe}
Analytic geometry was independently invented by René Descartes and Pierre de Fermat, although Descartes is sometimes given sole credit. *Cartesian geometry*, the alternative term used for analytic geometry, is named after Descartes.
Descartes made significant progress with the methods in an essay titled *La Géométrie (Geometry)*, one of the three accompanying essays (appendices) published in 1637 together with his *Discourse on the Method for Rightly Directing One\'s Reason and Searching for Truth in the Sciences*, commonly referred to as *Discourse on Method*. *La Geometrie*, written in his native French tongue, and its philosophical principles, provided a foundation for calculus in Europe. Initially the work was not well received, due, in part, to the many gaps in arguments and complicated equations. Only after the translation into Latin and the addition of commentary by van Schooten in 1649 (and further work thereafter) did Descartes\'s masterpiece receive due recognition.
Pierre de Fermat also pioneered the development of analytic geometry. Although not published in his lifetime, a manuscript form of *Ad locos planos et solidos isagoge* (Introduction to Plane and Solid Loci) was circulating in Paris in 1637, just prior to the publication of Descartes\' *Discourse*. Clearly written and well received, the *Introduction* also laid the groundwork for analytical geometry. The key difference between Fermat\'s and Descartes\' treatments is a matter of viewpoint: Fermat always started with an algebraic equation and then described the geometric curve that satisfied it, whereas Descartes started with geometric curves and produced their equations as one of several properties of the curves. As a consequence of this approach, Descartes had to deal with more complicated equations and he had to develop the methods to work with polynomial equations of higher degree. It was Leonhard Euler who first applied the coordinate method in a systematic study of space curves and surfaces.
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# Analytic geometry
## Coordinates
In analytic geometry, the plane is given a coordinate system, by which every point has a pair of real number coordinates. Similarly, Euclidean space is given coordinates where every point has three coordinates. The value of the coordinates depends on the choice of the initial point of origin. There are a variety of coordinate systems used, but the most common are the following:
### Cartesian coordinates (in a plane or space) {#cartesian_coordinates_in_a_plane_or_space}
The most common coordinate system to use is the Cartesian coordinate system, where each point has an *x*-coordinate representing its horizontal position, and a *y*-coordinate representing its vertical position. These are typically written as an ordered pair (*x*, *y*). This system can also be used for three-dimensional geometry, where every point in Euclidean space is represented by an ordered triple of coordinates (*x*, *y*, *z*).
### Polar coordinates (in a plane) {#polar_coordinates_in_a_plane}
In polar coordinates, every point of the plane is represented by its distance *r* from the origin and its angle *θ*, with *θ* normally measured counterclockwise from the positive *x*-axis. Using this notation, points are typically written as an ordered pair (*r*, *θ*). One may transform back and forth between two-dimensional Cartesian and polar coordinates by using these formulae: $x = r\, \cos\theta,\, y = r\, \sin\theta; \, r = \sqrt{x^2+y^2},\, \theta = \arctan(y/x).$ This system may be generalized to three-dimensional space through the use of cylindrical or spherical coordinates.
### Cylindrical coordinates (in a space) {#cylindrical_coordinates_in_a_space}
In cylindrical coordinates, every point of space is represented by its height *z*, its radius *r* from the *z*-axis and the angle *θ* its projection on the *xy*-plane makes with respect to the horizontal axis.
### Spherical coordinates (in a space) {#spherical_coordinates_in_a_space}
In spherical coordinates, every point in space is represented by its distance *ρ* from the origin, the angle *θ* its projection on the *xy*-plane makes with respect to the horizontal axis, and the angle *φ* that it makes with respect to the *z*-axis. The names of the angles are often reversed in physics.
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# Analytic geometry
## Equations and curves {#equations_and_curves}
In analytic geometry, any equation involving the coordinates specifies a subset of the plane, namely the solution set for the equation, or locus. For example, the equation *y* = *x* corresponds to the set of all the points on the plane whose *x*-coordinate and *y*-coordinate are equal. These points form a line, and *y* = *x* is said to be the equation for this line. In general, linear equations involving *x* and *y* specify lines, quadratic equations specify conic sections, and more complicated equations describe more complicated figures.
Usually, a single equation corresponds to a curve on the plane. This is not always the case: the trivial equation *x* = *x* specifies the entire plane, and the equation *x*^2^ + *y*^2^ = 0 specifies only the single point (0, 0). In three dimensions, a single equation usually gives a surface, and a curve must be specified as the intersection of two surfaces (see below), or as a system of parametric equations. The equation *x*^2^ + *y*^2^ = *r*^2^ is the equation for any circle centered at the origin (0, 0) with a radius of r.
### Lines and planes {#lines_and_planes}
Lines in a Cartesian plane, or more generally, in affine coordinates, can be described algebraically by *linear* equations. In two dimensions, the equation for non-vertical lines is often given in the *slope-intercept form*: $y = mx + b$ where:
- *m* is the slope or gradient of the line.
- *b* is the y-intercept of the line.
- *x* is the independent variable of the function *y* = *f*(*x*).
In a manner analogous to the way lines in a two-dimensional space are described using a point-slope form for their equations, planes in a three dimensional space have a natural description using a point in the plane and a vector orthogonal to it (the normal vector) to indicate its \"inclination\".
Specifically, let $\mathbf{r}_0$ be the position vector of some point $P_0 = (x_0,y_0,z_0)$, and let $\mathbf{n} = (a,b,c)$ be a nonzero vector. The plane determined by this point and vector consists of those points $P$, with position vector $\mathbf{r}$, such that the vector drawn from $P_0$ to $P$ is perpendicular to $\mathbf{n}$. Recalling that two vectors are perpendicular if and only if their dot product is zero, it follows that the desired plane can be described as the set of all points $\mathbf{r}$ such that $\mathbf{n} \cdot (\mathbf{r}-\mathbf{r}_0) =0.$ (The dot here means a dot product, not scalar multiplication.) Expanded this becomes $a (x-x_0)+ b(y-y_0)+ c(z-z_0)=0,$ `{{cn span|text=which is the ''point-normal'' form of the equation of a plane. |date=April 2022}}`{=mediawiki} This is just a linear equation: $ax + by + cz + d = 0, \text{ where } d = -(ax_0 + by_0 + cz_0).$ Conversely, it is easily shown that if *a*, *b*, *c* and *d* are constants and *a*, *b*, and *c* are not all zero, then the graph of the equation $ax + by + cz + d = 0,$ `{{cn span|text=is a plane having the vector <math>\mathbf{n} = (a,b,c)</math> as a normal.|date=April 2022}}`{=mediawiki} This familiar equation for a plane is called the *general form* of the equation of the plane.
In three dimensions, lines can *not* be described by a single linear equation, so they are frequently described by parametric equations: $x = x_0 + at$ $y = y_0 + bt$ $z = z_0 + ct$ where:
- *x*, *y*, and *z* are all functions of the independent variable *t* which ranges over the real numbers.
- (*x*~0~, *y*~0~, *z*~0~) is any point on the line.
- *a*, *b*, and *c* are related to the slope of the line, such that the vector (*a*, *b*, *c*) is parallel to the line.
### Conic sections {#conic_sections}
In the Cartesian coordinate system, the graph of a quadratic equation in two variables is always a conic section -- though it may be degenerate, and all conic sections arise in this way. The equation will be of the form $Ax^2 + Bxy + Cy^2 +Dx + Ey + F = 0\text{ with }A, B, C\text{ not all zero.}$ As scaling all six constants yields the same locus of zeros, one can consider conics as points in the five-dimensional projective space $\mathbf{P}^5.$
The conic sections described by this equation can be classified using the discriminant
$B^2 - 4AC .$ If the conic is non-degenerate, then:
- if $B^2 - 4AC < 0$, the equation represents an ellipse;
- if $A = C$ and $B = 0$, the equation represents a circle, which is a special case of an ellipse;
- if $B^2 - 4AC = 0$, the equation represents a parabola;
- if $B^2 - 4AC > 0$, the equation represents a hyperbola;
- if we also have $A + C = 0$, the equation represents a rectangular hyperbola.
### Quadric surfaces {#quadric_surfaces}
A **quadric**, or **quadric surface**, is a *2*-dimensional surface in 3-dimensional space defined as the locus of zeros of a quadratic polynomial. In coordinates `{{nowrap|''x''<sub>1</sub>, ''x''<sub>2</sub>,''x''<sub>3</sub>}}`{=mediawiki}, the general quadric is defined by the algebraic equation
$\sum_{i,j=1}^{3} x_i Q_{ij} x_j + \sum_{i=1}^{3} P_i x_i + R = 0.$
Quadric surfaces include ellipsoids (including the sphere), paraboloids, hyperboloids, cylinders, cones, and planes.
## Distance and angle {#distance_and_angle}
In analytic geometry, geometric notions such as distance and angle measure are defined using formulas. These definitions are designed to be consistent with the underlying Euclidean geometry. For example, using Cartesian coordinates on the plane, the distance between two points (*x*~1~, *y*~1~) and (*x*~2~, *y*~2~) is defined by the formula $d = \sqrt{(x_2 - x_1)^2 + (y_2 - y_1)^2},$ which can be viewed as a version of the Pythagorean theorem. Similarly, the angle that a line makes with the horizontal can be defined by the formula $\theta = \arctan(m),$ where *m* is the slope of the line.
In three dimensions, distance is given by the generalization of the Pythagorean theorem: $d = \sqrt{(x_2 - x_1)^2 + (y_2 - y_1)^2+ (z_2 - z_1)^2},$ while the angle between two vectors is given by the dot product. The dot product of two Euclidean vectors **A** and **B** is defined by $\mathbf A\cdot\mathbf B \stackrel{\mathrm{def}}{=} \left\|\mathbf A\right\| \left\|\mathbf B\right\| \cos\theta,$ where *θ* is the angle between **A** and **B**.
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# Analytic geometry
## Transformations
\[\[<File:FourGeometryTransformations.svg%7Cthumb%7C400px>\|
a\) y = f(x) = \|x\| `{{spaces|5}}`{=mediawiki} b) y = f(x+3) `{{spaces|5}}`{=mediawiki} c) y = f(x)-3 `{{spaces|5}}`{=mediawiki} d) y = 1/2 f(x)
\]\]
Transformations are applied to a parent function to turn it into a new function with similar characteristics.
The graph of $R(x,y)$ is changed by standard transformations as follows:
- Changing $x$ to $x-h$ moves the graph to the right $h$ units.
- Changing $y$ to $y-k$ moves the graph up $k$ units.
- Changing $x$ to $x/b$ stretches the graph horizontally by a factor of $b$. (think of the $x$ as being dilated)
- Changing $y$ to $y/a$ stretches the graph vertically.
- Changing $x$ to $x\cos A+ y\sin A$ and changing $y$ to $-x\sin A + y\cos A$ rotates the graph by an angle $A$.
There are other standard transformation not typically studied in elementary analytic geometry because the transformations change the shape of objects in ways not usually considered. Skewing is an example of a transformation not usually considered. For more information, consult the Wikipedia article on affine transformations.
For example, the parent function $y=1/x$ has a horizontal and a vertical asymptote, and occupies the first and third quadrant, and all of its transformed forms have one horizontal and vertical asymptote, and occupies either the 1st and 3rd or 2nd and 4th quadrant. In general, if $y=f(x)$, then it can be transformed into $y=af(b(x-k))+h$. In the new transformed function, $a$ is the factor that vertically stretches the function if it is greater than 1 or vertically compresses the function if it is less than 1, and for negative $a$ values, the function is reflected in the $x$-axis. The $b$ value compresses the graph of the function horizontally if greater than 1 and stretches the function horizontally if less than 1, and like $a$, reflects the function in the $y$-axis when it is negative. The $k$ and $h$ values introduce translations, $h$, vertical, and $k$ horizontal. Positive $h$ and $k$ values mean the function is translated to the positive end of its axis and negative meaning translation towards the negative end.
Transformations can be applied to any geometric equation whether or not the equation represents a function. Transformations can be considered as individual transactions or in combinations.
Suppose that $R(x,y)$ is a relation in the $xy$ plane. For example, $x^2+y^2-1=0$ is the relation that describes the unit circle.
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# Analytic geometry
## Finding intersections of geometric objects `{{anchor|Intersections}}`{=mediawiki} {#finding_intersections_of_geometric_objects}
For two geometric objects P and Q represented by the relations $P(x,y)$ and $Q(x,y)$ the intersection is the collection of all points $(x,y)$ which are in both relations.
For example, $P$ might be the circle with radius 1 and center $(0,0)$: $P = \{(x,y) | x^2+y^2=1\}$ and $Q$ might be the circle with radius 1 and center $(1,0): Q = \{(x,y) | (x-1)^2+y^2=1\}$. The intersection of these two circles is the collection of points which make both equations true. Does the point $(0,0)$ make both equations true? Using $(0,0)$ for $(x,y)$, the equation for $Q$ becomes $(0-1)^2+0^2=1$ or $(-1)^2=1$ which is true, so $(0,0)$ is in the relation $Q$. On the other hand, still using $(0,0)$ for $(x,y)$ the equation for $P$ becomes $0^2+0^2=1$ or $0=1$ which is false. $(0,0)$ is not in $P$ so it is not in the intersection.
The intersection of $P$ and $Q$ can be found by solving the simultaneous equations:
$x^2+y^2 = 1$ $(x-1)^2+y^2 = 1.$
Traditional methods for finding intersections include substitution and elimination.
**Substitution:** Solve the first equation for $y$ in terms of $x$ and then substitute the expression for $y$ into the second equation:
$x^2+y^2 = 1$ $y^2=1-x^2.$
We then substitute this value for $y^2$ into the other equation and proceed to solve for $x$: $(x-1)^2+(1-x^2)=1$ $x^2 -2x +1 +1 -x^2 =1$ $-2x = -1$ $x=1/2.$
Next, we place this value of $x$ in either of the original equations and solve for $y$:
$(1/2)^2+y^2 = 1$ $y^2 =3/4$ $y = \frac{\pm \sqrt{3}}{2}.$
So our intersection has two points: $\left(1/2,\frac{+ \sqrt{3}}{2}\right) \;\; \text{and} \;\; \left(1/2,\frac{-\sqrt{3}}{2}\right).$
**Elimination**: Add (or subtract) a multiple of one equation to the other equation so that one of the variables is eliminated. For our current example, if we subtract the first equation from the second we get $(x-1)^2-x^2=0$. The $y^2$ in the first equation is subtracted from the $y^2$ in the second equation leaving no $y$ term. The variable $y$ has been eliminated. We then solve the remaining equation for $x$, in the same way as in the substitution method:
$x^2 -2x +1 -x^2 =0$ $-2x = -1$ $x=1/2.$
We then place this value of $x$ in either of the original equations and solve for $y$: $(1/2)^2+y^2 = 1$ $y^2 = 3/4$ $y = \frac{\pm \sqrt{3}}{2}.$
So our intersection has two points: $\left(1/2,\frac{+ \sqrt{3}}{2}\right) \;\; \text{and} \;\; \left(1/2,\frac{-\sqrt{3}}{2}\right).$
For conic sections, as many as 4 points might be in the intersection.
### Finding intercepts {#finding_intercepts}
One type of intersection which is widely studied is the intersection of a geometric object with the $x$ and $y$ coordinate axes.
The intersection of a geometric object and the $y$-axis is called the $y$-intercept of the object. The intersection of a geometric object and the $x$-axis is called the $x$-intercept of the object.
For the line $y=mx+b$, the parameter $b$ specifies the point where the line crosses the $y$ axis. Depending on the context, either $b$ or the point $(0,b)$ is called the $y$-intercept.
## Geometric axis {#geometric_axis}
Axis in geometry is the perpendicular line to any line, object or a surface.
Also for this may be used the common language use as a: normal (perpendicular) line, otherwise in engineering as *axial line*.
In geometry, a **normal** is an object such as a line or vector that is perpendicular to a given object. For example, in the two-dimensional case, the **normal line** to a curve at a given point is the line perpendicular to the tangent line to the curve at the point.
In the three-dimensional case a **surface normal**, or simply **normal**, to a surface at a point *P* is a vector that is perpendicular to the tangent plane to that surface at *P*. The word \"normal\" is also used as an adjective: a line normal to a plane, the normal component of a force, the **normal vector**, etc. The concept of **normality** generalizes to orthogonality.
## Spherical and nonlinear planes and their tangents {#spherical_and_nonlinear_planes_and_their_tangents}
Tangent is the linear approximation of a spherical or other curved or twisted line of a function.
### Tangent lines and planes {#tangent_lines_and_planes}
In geometry, the **tangent line** (or simply **tangent**) to a plane curve at a given point is the straight line that \"just touches\" the curve at that point. Informally, it is a line through a pair of infinitely close points on the curve. More precisely, a straight line is said to be a tangent of a curve `{{nowrap|1=''y'' = ''f''(''x'')}}`{=mediawiki} at a point `{{nowrap|1=''x'' = ''c''}}`{=mediawiki} on the curve if the line passes through the point `{{nowrap|(''c'', ''f''(''c''))}}`{=mediawiki} on the curve and has slope `{{nowrap|''f''{{'}}`{=mediawiki}(*c*)}} where *f*{{\'}} is the derivative of *f*. A similar definition applies to space curves and curves in *n*-dimensional Euclidean space.
As it passes through the point where the tangent line and the curve meet, called the **point of tangency**, the tangent line is \"going in the same direction\" as the curve, and is thus the best straight-line approximation to the curve at that point.
Similarly, the **tangent plane** to a surface at a given point is the plane that \"just touches\" the surface at that point. The concept of a tangent is one of the most fundamental notions in differential geometry and has been extensively generalized; see Tangent space
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# Additive synthesis
**Additive synthesis** is a sound synthesis technique that creates timbre by adding sine waves together.
The timbre of musical instruments can be considered in the light of Fourier theory to consist of multiple harmonic or inharmonic *partials* or overtones. Each partial is a sine wave of different frequency and amplitude that swells and decays over time due to modulation from an ADSR envelope or low frequency oscillator.
Additive synthesis most directly generates sound by adding the output of multiple sine wave generators. Alternative implementations may use pre-computed wavetables or the inverse fast Fourier transform.
## Explanation
The sounds that are heard in everyday life are not characterized by a single frequency. Instead, they consist of a sum of pure sine frequencies, each one at a different amplitude. When humans hear these frequencies simultaneously, we can recognize the sound. This is true for both \"non-musical\" sounds (e.g. water splashing, leaves rustling, etc.) and for \"musical sounds\" (e.g. a piano note, a bird\'s tweet, etc.). This set of parameters (frequencies, their relative amplitudes, and how the relative amplitudes change over time) are encapsulated by the *timbre* of the sound. Fourier analysis is the technique that is used to determine these exact timbre parameters from an overall sound signal; conversely, the resulting set of frequencies and amplitudes is called the Fourier series of the original sound signal.
In the case of a musical note, the lowest frequency of its timbre is designated as the sound\'s fundamental frequency. For simplicity, we often say that the note is playing at that fundamental frequency (e.g. \"middle C is 261.6 Hz\"), even though the sound of that note consists of many other frequencies as well. The set of the remaining frequencies is called the overtones (or the harmonics, if their frequencies are integer multiples of the fundamental frequency) of the sound. In other words, the fundamental frequency alone is responsible for the pitch of the note, while the overtones define the timbre of the sound. The overtones of a piano playing middle C will be quite different from the overtones of a violin playing the same note; that\'s what allows us to differentiate the sounds of the two instruments. There are even subtle differences in timbre between different versions of the same instrument (for example, an upright piano vs. a grand piano).
Additive synthesis aims to exploit this property of sound in order to construct timbre from the ground up. By adding together pure frequencies (sine waves) of varying frequencies and amplitudes, we can precisely define the timbre of the sound that we want to create.
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# Additive synthesis
## Definitions
Harmonic additive synthesis is closely related to the concept of a Fourier series which is a way of expressing a periodic function as the sum of sinusoidal functions with frequencies equal to integer multiples of a common fundamental frequency. These sinusoids are called harmonics, overtones, or generally, partials. In general, a Fourier series contains an infinite number of sinusoidal components, with no upper limit to the frequency of the sinusoidal functions and includes a DC component (one with frequency of 0 Hz). Frequencies outside of the human audible range can be omitted in additive synthesis. As a result, only a finite number of sinusoidal terms with frequencies that lie within the audible range are modeled in additive synthesis.
A waveform or function is said to be periodic if
: $y(t) = y(t+P)$
for all $t$ and for some period $P$.
The Fourier series of a periodic function is mathematically expressed as:
: \\begin{align}
` y(t) &= \frac{a_0}{2} + \sum_{k=1}^{\infty} \left[ a_k \cos(2 \pi k f_0 t ) - b_k \sin(2 \pi k f_0 t ) \right] \\`\
` &= \frac{a_0}{2} + \sum_{k=1}^{\infty} r_k \cos\left(2 \pi k f_0 t + \phi_k \right) \\`\
` \end{align} `
where
- $f_0 = 1/P$ is the fundamental frequency of the waveform and is equal to the reciprocal of the period,
- $a_k = r_k \cos(\phi_k) = 2 f_0 \int_{0}^P y(t) \cos(2 \pi k f_0 t)\, dt, \quad k \ge 0$
- $b_k = r_k \sin(\phi_k) = -2 f_0 \int_{0}^P y(t) \sin(2 \pi k f_0 t)\, dt, \quad k \ge 1$
- $r_k = \sqrt{a_k^2 + b_k^2}$ is the amplitude of the $k$th harmonic,
- $\phi_k = \operatorname{atan2}(b_k, a_k)$ is the phase offset of the $k$th harmonic. atan2 is the four-quadrant arctangent function,
Being inaudible, the DC component, $a_0/2$, and all components with frequencies higher than some finite limit, $K f_0$, are omitted in the following expressions of additive synthesis.
### Harmonic form {#harmonic_form}
The simplest harmonic additive synthesis can be mathematically expressed as:
where $y(t)$ is the synthesis output, $r_k$, $k f_0$, and $\phi_k$ are the amplitude, frequency, and the phase offset, respectively, of the $k$th harmonic partial of a total of $K$ harmonic partials, and $f_0$ is the fundamental frequency of the waveform and the frequency of the musical note.
### Time-dependent amplitudes {#time_dependent_amplitudes}
-- -------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------
Example of harmonic additive synthesis in which each harmonic has a time-dependent amplitude. The fundamental frequency is 440 Hz. Problems listening to this file? See Media help
-- -------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------
More generally, the amplitude of each harmonic can be prescribed as a function of time, $r_k(t)$, in which case the synthesis output is
Each envelope $r_k(t)\,$ should vary slowly relative to the frequency spacing between adjacent sinusoids. The bandwidth of $r_k(t)$ should be significantly less than $f_0$.
### Inharmonic form {#inharmonic_form}
Additive synthesis can also produce inharmonic sounds (which are aperiodic waveforms) in which the individual overtones need not have frequencies that are integer multiples of some common fundamental frequency. While many conventional musical instruments have harmonic partials (e.g. an oboe), some have inharmonic partials (e.g. bells). Inharmonic additive synthesis can be described as
: $y(t) = \sum_{k=1}^{K} r_k(t) \cos\left(2 \pi f_k t + \phi_k \right),$
where $f_k$ is the constant frequency of $k$th partial.
-- -------------------------------------------------------------------------------------------------------------------------------------------------------------------------
Example of inharmonic additive synthesis in which both the amplitude and frequency of each partial are time-dependent. Problems listening to this file? See Media help
-- -------------------------------------------------------------------------------------------------------------------------------------------------------------------------
### Time-dependent frequencies {#time_dependent_frequencies}
In the general case, the instantaneous frequency of a sinusoid is the derivative (with respect to time) of the argument of the sine or cosine function. If this frequency is represented in hertz, rather than in angular frequency form, then this derivative is divided by $2 \pi$. This is the case whether the partial is harmonic or inharmonic and whether its frequency is constant or time-varying.
In the most general form, the frequency of each non-harmonic partial is a non-negative function of time, $f_k(t)$, yielding
### Broader definitions {#broader_definitions}
*Additive synthesis* more broadly may mean sound synthesis techniques that sum simple elements to create more complex timbres, even when the elements are not sine waves. For example, F. Richard Moore listed additive synthesis as one of the \"four basic categories\" of sound synthesis alongside subtractive synthesis, nonlinear synthesis, and physical modeling. In this broad sense, pipe organs, which also have pipes producing non-sinusoidal waveforms, can be considered as a variant form of additive synthesizers. Summation of principal components and Walsh functions have also been classified as additive synthesis.
## Implementation methods {#implementation_methods}
Modern-day implementations of additive synthesis are mainly digital. (See section *Discrete-time equations* for the underlying discrete-time theory)
### Oscillator bank synthesis {#oscillator_bank_synthesis}
Additive synthesis can be implemented using a bank of sinusoidal oscillators, one for each partial.
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# Additive synthesis
## Implementation methods {#implementation_methods}
### Wavetable synthesis {#wavetable_synthesis}
In the case of harmonic, quasi-periodic musical tones, wavetable synthesis can be as general as time-varying additive synthesis, but requires less computation during synthesis. As a result, an efficient implementation of time-varying additive synthesis of harmonic tones can be accomplished by use of *wavetable synthesis*.
#### Group additive synthesis {#group_additive_synthesis}
Group additive synthesis is a method to group partials into harmonic groups (having different fundamental frequencies) and synthesize each group separately with *wavetable synthesis* before mixing the results.
### Inverse FFT synthesis {#inverse_fft_synthesis}
An inverse fast Fourier transform can be used to efficiently synthesize frequencies that evenly divide the transform period or \"frame\". By careful consideration of the DFT frequency-domain representation it is also possible to efficiently synthesize sinusoids of arbitrary frequencies using a series of overlapping frames and the inverse fast Fourier transform.
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# Additive synthesis
## Additive analysis/resynthesis {#additive_analysisresynthesis}
It is possible to analyze the frequency components of a recorded sound giving a \"sum of sinusoids\" representation. This representation can be re-synthesized using additive synthesis. One method of decomposing a sound into time varying sinusoidal partials is short-time Fourier transform (STFT)-based McAulay-Quatieri Analysis.
By modifying the sum of sinusoids representation, timbral alterations can be made prior to resynthesis. For example, a harmonic sound could be restructured to sound inharmonic, and vice versa. Sound hybridisation or \"morphing\" has been implemented by additive resynthesis.
Additive analysis/resynthesis has been employed in a number of techniques including Sinusoidal Modelling, Spectral Modelling Synthesis (SMS), and the Reassigned Bandwidth-Enhanced Additive Sound Model. Software that implements additive analysis/resynthesis includes: SPEAR, LEMUR, LORIS, SMSTools, ARSS.
### Products
New England Digital Synclavier had a resynthesis feature where samples could be analyzed and converted into \"timbre frames\" which were part of its additive synthesis engine. Technos acxel, launched in 1987, utilized the additive analysis/resynthesis model, in an FFT implementation.
Also a vocal synthesizer, Vocaloid have been implemented on the basis of additive analysis/resynthesis: its spectral voice model called Excitation plus Resonances (EpR) model is extended based on Spectral Modeling Synthesis (SMS), and its diphone concatenative synthesis is processed using *spectral peak processing* (SPP) technique similar to modified phase-locked vocoder (an improved phase vocoder for formant processing). Using these techniques, spectral components (*formants*) consisting of purely harmonic partials can be appropriately transformed into desired form for sound modeling, and sequence of short samples (*diphones* or *phonemes*) constituting desired phrase, can be smoothly connected by interpolating matched partials and formant peaks, respectively, in the inserted transition region between different samples. (See also Dynamic timbres)
## Applications
### Musical instruments {#musical_instruments}
Additive synthesis is used in electronic musical instruments. It is the principal sound generation technique used by Eminent organs.
### Speech synthesis {#speech_synthesis}
In linguistics research, harmonic additive synthesis was used in the 1950s to play back modified and synthetic speech spectrograms.
Later, in the early 1980s, listening tests were carried out on synthetic speech stripped of acoustic cues to assess their significance. Time-varying formant frequencies and amplitudes derived by linear predictive coding were synthesized additively as pure tone whistles. This method is called sinewave synthesis. Also the composite sinusoidal modeling (CSM) used on a singing speech synthesis feature on the Yamaha CX5M (1984), is known to use a similar approach which was independently developed during 1966--1979. These methods are characterized by extraction and recomposition of a set of significant spectral peaks corresponding to the several resonance modes occurring in the oral cavity and nasal cavity, in a viewpoint of acoustics. This principle was also utilized on a physical modeling synthesis method, called modal synthesis.
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# Additive synthesis
## History
Harmonic analysis was discovered by Joseph Fourier, who published an extensive treatise of his research in the context of heat transfer in 1822. The theory found an early application in prediction of tides. Around 1876, William Thomson (later ennobled as Lord Kelvin) constructed a mechanical tide predictor. It consisted of a *harmonic analyzer* and a *harmonic synthesizer*, as they were called already in the 19th century. The analysis of tide measurements was done using James Thomson\'s *integrating machine*. The resulting Fourier coefficients were input into the synthesizer, which then used a system of cords and pulleys to generate and sum harmonic sinusoidal partials for prediction of future tides. In 1910, a similar machine was built for the analysis of periodic waveforms of sound. The synthesizer drew a graph of the combination waveform, which was used chiefly for visual validation of the analysis.
Georg Ohm applied Fourier\'s theory to sound in 1843. The line of work was greatly advanced by Hermann von Helmholtz, who published his eight years worth of research in 1863. Helmholtz believed that the psychological perception of tone color is subject to learning, while hearing in the sensory sense is purely physiological. He supported the idea that perception of sound derives from signals from nerve cells of the basilar membrane and that the elastic appendages of these cells are sympathetically vibrated by pure sinusoidal tones of appropriate frequencies. Helmholtz agreed with the finding of Ernst Chladni from 1787 that certain sound sources have inharmonic vibration modes.
In Helmholtz\'s time, electronic amplification was unavailable. For synthesis of tones with harmonic partials, Helmholtz built an electrically excited array of tuning forks and acoustic resonance chambers that allowed adjustment of the amplitudes of the partials. Built at least as early as in 1862, these were in turn refined by Rudolph Koenig, who demonstrated his own setup in 1872. For harmonic synthesis, Koenig also built a large apparatus based on his *wave siren*. It was pneumatic and utilized cut-out tonewheels, and was criticized for low purity of its partial tones. Also tibia pipes of pipe organs have nearly sinusoidal waveforms and can be combined in the manner of additive synthesis.
In 1938, with significant new supporting evidence, it was reported on the pages of Popular Science Monthly that the human vocal cords function like a fire siren to produce a harmonic-rich tone, which is then filtered by the vocal tract to produce different vowel tones. By the time, the additive Hammond organ was already on market. Most early electronic organ makers thought it too expensive to manufacture the plurality of oscillators required by additive organs, and began instead to build subtractive ones. In a 1940 Institute of Radio Engineers meeting, the head field engineer of Hammond elaborated on the company\'s new *Novachord* as having a *\"subtractive system\"* in contrast to the original Hammond organ in which *\"the final tones were built up by combining sound waves\"*. Alan Douglas used the qualifiers *additive* and *subtractive* to describe different types of electronic organs in a 1948 paper presented to the Royal Musical Association. The contemporary wording *additive synthesis* and *subtractive synthesis* can be found in his 1957 book *The electrical production of music*, in which he categorically lists three methods of forming of musical tone-colours, in sections titled *Additive synthesis*, *Subtractive synthesis*, and *Other forms of combinations*.
A typical modern additive synthesizer produces its output as an electrical, analog signal, or as digital audio, such as in the case of software synthesizers, which became popular around year 2000.
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# Additive synthesis
## History
### Timeline
The following is a timeline of historically and technologically notable analog and digital synthesizers and devices implementing additive synthesis.
Research implementation or publication Commercially available Company or institution Synthesizer or synthesis device Description Audio samples
---------------------------------------- ------------------------ ------------------------------------ --------------------------------- -------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------- -----------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------
1900 1906 New England Electric Music Company Telharmonium The first polyphonic, touch-sensitive music synthesizer. Implemented sinuosoidal additive synthesis using tonewheels and alternators. Invented by Thaddeus Cahill. *no known recordings*
1933 1935 Hammond Organ Company Hammond Organ An electronic additive synthesizer that was commercially more successful than Telharmonium. Implemented sinusoidal additive synthesis using tonewheels and magnetic pickups. Invented by Laurens Hammond.
1950 or earlier Haskins Laboratories Pattern Playback A speech synthesis system that controlled amplitudes of harmonic partials by a spectrogram that was either hand-drawn or an analysis result. The partials were generated by a multi-track optical tonewheel. [samples](http://www.haskins.yale.edu/featured/sentences/ppsentences.html)
1958 ANS An additive synthesizer that played microtonal spectrogram-like scores using multiple multi-track optical tonewheels. Invented by Evgeny Murzin. A similar instrument that utilized electronic oscillators, the *Oscillator Bank*, and its input device *Spectrogram* were realized by Hugh Le Caine in 1959.
1963 MIT An off-line system for digital spectral analysis and resynthesis of the attack and steady-state portions of musical instrument timbres by David Luce.
1964 University of Illinois Harmonic Tone Generator An electronic, harmonic additive synthesis system invented by James Beauchamp. [samples](https://web.archive.org/web/20131228061841/http://ems.music.uiuc.edu/beaucham/htg_sounds/) ([info](https://web.archive.org/web/20120322191551/http://ems.music.uiuc.edu/beaucham/htg.html))
1974 or earlier 1974 RMI Harmonic Synthesizer The first synthesizer product that implemented additive synthesis using digital oscillators. The synthesizer also had a time-varying analog filter. RMI was a subsidiary of Allen Organ Company, which had released the first commercial digital church organ, the *Allen Computer Organ*, in 1971, using digital technology developed by North American Rockwell. [1](https://soundcloud.com/doombient-music/rmi-harmonic-drones) [2](https://soundcloud.com/doombient-music/rmi-harmonic-demos) [3](https://soundcloud.com/doombient-music/rmi-harmonic-arpeggiator-demo) [4](https://soundcloud.com/doombient-music/rmi-harmonic-intermodulation)
1974 EMS (London) Digital Oscillator Bank A bank of digital oscillators with arbitrary waveforms, individual frequency and amplitude controls, intended for use in analysis-resynthesis with the digital *Analysing Filter Bank* (AFB) also constructed at EMS. Also known as: *DOB*. in The New Sound of Music
1976 1976 Fairlight Qasar M8 An all-digital synthesizer that used the fast Fourier transform to create samples from interactively drawn amplitude envelopes of harmonics. [samples](http://anerd.com/fairlight/audioarchives/index.htm)
1977 Bell Labs Digital Synthesizer A real-time, digital additive synthesizer that has been called the first true digital synthesizer. Also known as: *Alles Machine*, *Alice*. [sample](http://retiary.org/ls/music/realaudio/ob_sys/05_alles_synth_improv.rm) ([info](http://retiary.org/ls/obsolete_systems/))
1979 1979 New England Digital Synclavier II A commercial digital synthesizer that enabled development of timbre over time by smooth cross-fades between waveforms generated by additive synthesis.
1996 Kawai K5000 A commercial digital synthesizer workstation capable of polyphonic, digital additive synthesis of up to 128 sinusodial waves, as well as combing PCM waves.
## Discrete-time equations {#discrete_time_equations}
In digital implementations of additive synthesis, discrete-time equations are used in place of the continuous-time synthesis equations. A notational convention for discrete-time signals uses brackets i.e. $y[n]\,$ and the argument $n\,$ can only be integer values. If the continuous-time synthesis output $y(t)\,$ is expected to be sufficiently bandlimited; below half the sampling rate or $f_\mathrm{s}/2\,$, it suffices to directly sample the continuous-time expression to get the discrete synthesis equation. The continuous synthesis output can later be reconstructed from the samples using a digital-to-analog converter. The sampling period is $T=1/f_\mathrm{s}\,$.
Beginning with (`{{EquationNote|3}}`{=mediawiki}),
: $y(t) = \sum_{k=1}^{K} r_k(t) \cos\left(2 \pi \int_0^t f_k(u)\ du + \phi_k \right)$
and sampling at discrete times $t = nT = n/f_\mathrm{s} \,$ results in
$$\begin{align}
y[n] & = y(nT) = \sum_{k=1}^{K} r_k(nT) \cos\left(2 \pi \int_0^{nT} f_k(u)\ du + \phi_k \right) \\
& = \sum_{k=1}^{K} r_k(nT) \cos\left(2 \pi \sum_{i=1}^{n} \int_{(i-1)T}^{iT} f_k(u)\ du + \phi_k \right) \\
& = \sum_{k=1}^{K} r_k(nT) \cos\left(2 \pi \sum_{i=1}^{n} (T f_k[i]) + \phi_k \right) \\
& = \sum_{k=1}^{K} r_k[n] \cos\left(\frac{2 \pi}{f_\mathrm{s}} \sum_{i=1}^{n} f_k[i] + \phi_k \right) \\
\end{align}$$ where
: $r_k[n] = r_k(nT) \,$ is the discrete-time varying amplitude envelope
: $f_k[n] = \frac{1}{T} \int_{(n-1)T}^{nT} f_k(t)\ dt \,$ is the discrete-time backward difference instantaneous frequency.
This is equivalent to
: $y[n] = \sum_{k=1}^{K} r_k[n] \cos\left( \theta_k[n] \right)$
where
$$\begin{align}
\theta_k[n] &= \frac{2 \pi}{f_\mathrm{s}} \sum_{i=1}^{n} f_k[i] + \phi_k \\
&= \theta_k[n-1] + \frac{2 \pi}{f_\mathrm{s}} f_k[n] \\
\end{align}$$ for all $n>0\,$ and
: $\theta_k[0] = \phi_k
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# Argentine cuisine
**Argentine cuisine** is described as a blending of cultures, from the Indigenous peoples of Argentina who focused on ingredients such as humita, potatoes, cassava, peppers, tomatoes, beans, and yerba mate, to Mediterranean influences brought by the Spanish during the colonial period. This was complemented by the significant influx of Italian and Spanish immigrants to Argentina during the 19th and 20th centuries, who incorporated plenty of their food customs and dishes such as pizzas, pasta and Spanish tortillas.
Beef is a main part of the Argentine diet due to its vast production in the country\'s plains. In fact, Argentine annual consumption of beef has averaged 100 kg per capita, approaching 180 kg per capita during the 19th century; consumption averaged 67.7 kg in 2007.
Beyond *asado* (the Argentine barbecue), no other dish more genuinely matches the national identity. Nevertheless, the country\'s vast area, and its cultural diversity, have led to a local cuisine of various dishes.
The great immigratory waves consequently imprinted a large influence in the Argentine cuisine, after all Argentina was the second country in the world with the most immigrants with 6.6 million, only second to the United States with 27 million, and ahead of other immigratory receptor countries such as Canada, Brazil, Australia, etc.
Argentine people have a reputation for their love of eating. Social gatherings are commonly centred on sharing a meal. Invitations to have dinner at home are generally viewed as a symbol of friendship, warmth, and integration. Sunday family lunch is considered the most significant meal of the week, whose highlights often include *asado* or pasta.
Another feature of Argentine cuisine is the preparation of homemade food such as French fries, patties, and pasta to celebrate a special occasion, to meet friends, or to honour someone. Homemade food is also seen as a way to show affection.
Argentine restaurants include a great variety of cuisines, prices, and flavours. Large cities tend to host everything from high-end international cuisine to *bodegones* (inexpensive traditional hidden taverns), less stylish restaurants, and bars and canteens offering a range of dishes at affordable prices.
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# Argentine cuisine
## History
Amerindians lived in Argentina thousands of years before European explorers arrived. They mostly lived off of hunting, gathering, and fishing. Generally, the most common crops at this time were maize, potatoes, common beans, quinoa, and squash.
The Argentinian native people could be divided in three groups based on their main modality of acquiring food:
- Hunters and gatherers who inhabited the Patagonia, Pampa, and Chaco regions.
- Farmers in the northwestern, Cuyo, and Cordoba\'s mountain regions who mostly grew squash, melons, and sweet potatoes. These groups had great influence from Andean-Incan tradition.
- Farmers in the Mesopotamia plains who belonged to the guaraní culture.
Spanish settlers came to Argentina in 1536 and began building *chacras* where Amerindians would work to harvest the food. The arrival of Europeans brought Argentina into the Columbian Exchange, with ingredients from the Old World such as wheat, grapevine, figs, and several kinds of fruits being introduced to the country for the first time. It was also during the Spanish colonial period that cattle, goat, and pig farming were first introduced to Argentina, forming the foundation of the large Argentine beef industry.
Between 1853 and 1955, 6.6 million immigrants came to live in Argentina from Europe (especially from Italy, Wales, Germany and Switzerland), the Near and Middle East, Russia and Japan. They contributed to the development of Argentine cuisine by encouraging the production of a wider variety of foods. They also bought lands where they built *chacras* and encouraged the growth of farming. By this point, Argentina was the country with most immigrants only second to the United States.
During the XIX century, social standing was not associated with access to food. The price of beef, fish, and bird meats was cheap and accessible. However, grains and wheat was scarce so bread was very expensive. Some of the most common dishes during this time were soups with pork chunks, cooked partridge with legumes, spinach bread, beef slices, and lamb stew. The most prominent spices were garlic, parsley, and pepper.
By the turn of the century, Argentine Cuisine was on a constant decline due to shortage of several ingredients. However, eating habits began to shift with further immigration which facilitated a gastronomic revolution. Most immigrants in the 1900s came from Italy and Spain. The Italians introduced pizza, as well as a variety of pasta dishes, including spaghetti and lasagna. British, German, Jewish, and other immigrants also settled in Argentina, all bringing their styles of cooking and favorite foods with them. The British brought tea, starting the tradition of teatime. All of these cultures influenced the dishes of Argentina.
At this time, Italian cuisine began to really become a part of the cuisine. The neighborhood of La Boca, Buenos Aires, was the first big Italian hub, and from here plenty of traditionally Italian ingredients and eating habits expanded across the country. Different kinds of pastas such as long noodles or *tallarines*, gnocchi, ravioli, and cannelloni filled with ricotta cheese became popular along with pizza, fainá (Argentinian version of the traditional Italian farinata), and milanesas. Different ways of preparing dishes were also adopted from Italian immigrants. These included the preparation of ice cream, fish, and shellfish. Spanish immigrants also left their mark, popularizing eating dry nuts, tomato sauce, pesto, olives, and olive oil. Additionally, deli stores started to incorporate traditional Iberian hams and sausages and great varieties of cheeses yet these were more limited. They were also mainly responsible for the massive diffusion of wine consumption, among some other habits. This occurred at the same time that other global products began arriving to Argentina such as saffron, cod, different varieties of beans, chickpeas, additional spices, chocolates, and tea.
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# Argentine cuisine
## Typical foods {#typical_foods}
Most regions of Argentina are known for their beef-oriented diet. Grilled meat from the *asado* (barbecue) is a staple, with steak and beef ribs especially common. The term *asado* itself refers to long strips of flank-cut beef ribs.
Popular items such as *chorizo* (pork sausage), *morcilla* (blood sausage), *chinchulines* (chitterlings), *mollejas* (sweetbread), and other parts of the animal are also enjoyed.
In Patagonia, however, lamb and chivito (goat) are eaten more frequently than beef. Whole lambs and goats are traditionally cooked over an open fire in a technique known as asado a la estaca.
The most common condiment for asado is *chimichurri*, a sauce of herbs, garlic and vinegar. Unlike other preparations, Argentines do not include chilli in their version of *chimichurri*, but it does include a still-spicy, but milder form of red pepper, ají molido.
Breaded and fried meats (*milanesas)* are used as snacks, in sandwiches, or eaten warm with mashed potatoes, *purée*. *Empanadas,* small pastries of meat, cheese, sweet corn, and many other fillings, are a common sight at parties and picnics, or as starters to a meal. They also vary in their looks, since they are folded with a traditional decorative edging called *repulgue*. The *repulgue* is not just aesthetic, but also serves as a way to identify the flavor of each empanada since they are traditionally ordered in dozens where people mix and match flavors. Empanadas are one of the most important staples of this country due to the wide array of varieties.
The empanadas seen in Argentina today originate from a Spanish dish from the fifteenth century where travelers used easy-to-carry bread and filled it with a variety of ingredients. Eventually it evolved into a popular gastronomic item and spread across the world. Variations of empanadas both inside and outside of Argentina include the *empanada gallega* (Galician *empanada*), a large round meat pie made most commonly with tuna and mackerel (*caballa* in Spanish).
Vegetables and salads are also eaten by Argentines; tomatoes, onions, lettuce, eggplants, squashes, and zucchini are common side dishes.
Italian staples, such as pizza and pasta, are eaten as commonly as beef. *Fideos* (noodles), *tallarines* (*fettuccine* and *tagliatelle*), *ñoquis* (*gnocchi*) are traditionally served on the 29th day of the month, *ravioles*, and *canelones* (*cannelloni*) can be bought freshly made in many establishments in the larger cities. Italian-style ice cream is served in large parlours and even drive-through businesses. Other Italian staples are *polenta*, *tarta pascualina*, and *pastafrola*.
In Chubut, the Welsh community is known for its teahouses, offering scones and *torta galesa*, which is rather like *torta negra*.
A fosforito is a ham and cheese sandwich using puff pastry as the bread. *Sandwiches de miga* are delicate sandwiches made with crustless buttered English bread, very thinly sliced cured meat, cheese, and lettuce. They are often purchased from entrepreneurial home cooks and may be eaten for a light evening meal.
A sweet paste, *dulce de leche* is another treasured national food, used to fill cakes and pancakes, spread over toasted bread for breakfast, or served with ice cream. In terms of sweets, *Alfajores* are another key staple. These are shortbread cookies sandwiched together with chocolate and *dulce de leche* or a fruit paste. The \"policeman\'s\" or \"truck driver\'s\" sweet is cheese with quince paste or *dulce de membrillo*. *Dulce de batata* is made of sweet potato/yam: this with cheese is the *Martín Fierro*\'s sweet. Additionally, ice cream shops or *heladerias* are a big boom especially in the city of Buenos Aires. Argentinian ice cream comes in plenty of flavors (from fruits to cheesecake and even dulce de leche flavors) and has a special smoothness as it follows a recipe very similar to that of Italian gelato.
Apples, pears, peaches, kiwifruits, avocados, and plums are major exports.
A traditional drink of Argentina is an infusion called *mate* (in Spanish, *mate*, with the accent on the first syllable \[MAH-teh\]). The name comes from the hollow gourd from which it is traditionally drunk.
The *mate* (gourd) or other small cup is filled about three-quarters full with *yerba mate*, the dried leaves and twigs of the *Ilex paraguariensis*. The drink, which is rather bitter, is sipped through a metal or cane straw called a *bombilla*. *Mate* can be sweetened with sugar, or flavoured with aromatic herbs or dried orange peel.
Hot but not boiling water is poured into the gourd, drunk, then the *mate* is refilled. The *mate* is nearly full of leaves, so each refill only makes a small drink, but many refills are possible before the *yerba* is spent. In small gatherings it is traditional for one *mate* to be passed from person to person, filled by whoever has the kettle. It is customary not to thank the refiller routinely; a final *gracias* (thank you) implies that the drinker has had enough.
Drinking *mate* together is an important social ritual. *Mate cocido* is the same leaf, which rather than brewed is boiled and served, like tea, with milk and sugar to taste.
Other typical drinks include wine (sometimes with soda water added); tea and coffee are equally important. Quilmes is the national brand of pale lager, named after the town of Quilmes, Buenos Aires, where it was first produced.
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# Argentine cuisine
## Ingredients
Argentine cuisine uses locally-grown cereals, grains, oil seeds, fruits and vegetables, as well as meat.
Meat products have been dominant in the country since the 16th century. The country is regarded as a major beef, pork and poultry producing and consuming country. Certain areas such as those located in the south are usually engaged in activities involving sheep and lamb breeding, and shellfish, crustaceans, molluscs and salmonides fishing.
The vast breeding activity involving any type of cattle has given rise to a highly developed dairy industry that includes products like cow, sheep and camelide, *dulce de leche* and yogurts. Some of the cheeses from Argentina are *reggianito*, *sardo*, *provoleta* and *cremoso*. Argentina can also be conceived as a great industry engaged in the production of dried fruits, olives, all types of oils and spices.
In the Mesopotamia region, river fish such as silverside, surubi, dorado or boga are common.
## Regional differences {#regional_differences}
Argentine cuisine is heavily influenced by its European roots and has regional variations. *Asado*, *dulce de leche*, *empanadas*, and *yerba mate* are found throughout Argentina. In many parts of the country, food is prepared differently and different kinds of foods are made; this includes to a smaller degree food from pre-Columbian times, as in the Northwest.
### Central region and la Pampa {#central_region_and_la_pampa}
This region is composed of the city of Buenos Aires, Buenos Aires Province, Córdoba, La Pampa, Santa Fe, and Entre Ríos.
This region, especially within the larger urban areas of Buenos Aires, Rosario, and Córdoba welcomed European immigrants. These were especially of Italian and Spanish descent. Nevertheless, there was also a migratory flow of German, Swiss, and Middle Eastern immigrants arriving in Argentina. As a result, dishes such as pasta, pizza, pucheros (stews), croquetas (fritters), sauces, embutidos (sausages), and chicken and meat courses brought a wider scope of options to daily menus. The bread-making, dessert, pastry, and dairy industries have achieved considerable development in this region.
The above-mentioned dishes have developed a distinctively Argentine nuance. That is why, for example, Argentine pasta includes a wide variety of dishes ranging from spaghetti, fusiles (fusilli), ñoquis (gnocchi), ravioli, cintas (pasta ribbons), and lasagne to the Argentine-made sorrentinos, agnolottis (agnolotti), canelones (cannelloni), and fetuchines (fettuccine).
Pizza---made with very thin, and sometimes thick, high-rising doughs, with or without cheese, cooked in the oven or *a la piedra* (on a stone oven), and stuffed with numerous ingredients---is a dish which can be found in nearly every corner of the country. Buenos Aires, Rosario, and Córdoba also serve it with fainá, which is a chick pea-flour dough placed over the piece of pizza. People say that what makes Argentine pizza unique is the blending of Italian and Spanish cultures. At the turn of the 19th century, immigrants from Naples and Genoa opened the first pizza bars, though Spanish residents subsequently owned most of the pizza businesses.
Bread products are consumed all around the country. The deeply rooted bread, pastry, and dessert-making tradition derive from blending the above nationalities\' products. Bakeries sell not only a wide scope of bread, cookies, and cakes, but also pastries. The latter resembles a sort of roll pastry whose main dough ingredient is either butter or fat and which may be simple or stuffed with dulce de leche, milk, jam, crema pastel, or quince or apple jelly, among other fillings. The most popular type of pastry is said to be that of *medialunas* (singular: *medialuna,* literally half-moon, that is to say, crescent), based upon French croissants. Sandwiches de miga are another type of bread products; they are made only with thin layers of white bread (generally referred to as crustless bread) and stuffed with food items ranging from ham and cheese to other more sophisticated combinations such as raw ham, tomatoes, olives, hard-boiled eggs, tuna, lettuce, red pepper, and the like.
Desserts and sweets are usually stuffed or covered with dulce de leche. The latter can be eaten alone or on top of cakes, alfajores, panqueques (crepes), and pastries, or as a topping spread over flan de leche. Chantilly cream is widely consumed and used in preparing sweets and desserts. Additionally, cakes, sponge cakes, and puddings are very popular dishes. Italian ice creams in this region also achieved a significant degree of development by adding local flavours that somehow preserved the local spirit involved in their preparation.
Although asado is eaten all over the country, its origin may be traced back to the Pampas. It entails many types of meat, which are generally eaten as follows: achuras (offal), morcilla (blood sausage), and sometimes also a provoleta (a piece of provolone cheese cooked on the grill with oregano) are eaten first. Then comes the choripán (a kind of spiced sausage made with pork or lamb and placed between two slices of bread), and finally meat such as asado de tira, vacío (flank steak), lomo (tenderloin), colita de cuadril (rump), matambre (rolled stuffed steak cut into slices and served cold), entraña (hanger steak); the list is never-ending. *Cabrito al asador* (roast kid or goat) is frequently eaten in the province of Córdoba.
### Northwest and Cuyo {#northwest_and_cuyo}
This region includes the provinces of Jujuy, Salta, Catamarca, Tucumán, Santiago del Estero, La Rioja, San Juan, Mendoza, and San Luis. It is also regarded as the one most influenced by Native Americans, and its foods are closely linked to the Andean-Incan tradition. When preparing regional dishes, potatoes and corn or wheat are almost always used, including quinoa (a cereal typically used in Incan cuisine), peppers, squashes, tomatoes and in some provinces beans. The most celebrated dishes are humita and tamal, in which the corn husk is stuffed with the corn filling itself, seasonings or meat.
This region is the most suitable to taste empanadas, particularly those stuffed with meat and offering different types of tempting varieties such as the *meat empanada*, salteña also filled with potatoes, or the *empanada tucumana*, which is stuffed with matambre and cut with a knife, or empanadas made with cheese. Empanadas are individual-sized and closed savoury pastries which may be fried or baked in the oven and are generally eaten with the hands.
Stews such as locro, carbonada, pollo al disco, and cazuelas (casseroles) are also typical dishes characterizing this region, which also include pumpkin or potato pudding stuffed with meat.
There are also some local holidays in this region related to food. For example, in Salta they hold a festival dedicated to a locally grown bean similar to Edamame. During this holiday, the traditional foods of corn and beans are celebrated. Meals of all kinds are eaten, always with these two ingredients as a side dish, and even competitions of who can eat a set number of beans in the shortest period of time are held.
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# Argentine cuisine
## Regional differences {#regional_differences}
### Mesopotamia
The humid and verdant area of north-east Argentina known as Mesopotamia, comprising the provinces of Chaco, Corrientes, Misiones and Formosa is another area heavily influenced by Native Americans, particularly by the Guaraní tribe. Abounding in rivers and shores, it offers a wide diversity of fish species, such as dorado, pacú, surubi, boga and silverside.
Widely grown in this area, cassava is typically included in the region\'s dishes, as are other components of meals, such as the chipá (cassava and cheese bread). However, in this area Cassava is cooked alone too, boiled or fried, often as a side dish for Asado and empanadas. As well, mbeyú, chipá avatí, sopa paraguaya, sopa correntina, chipa solo or chipá con carne, el quibebé, el borí borí, chipá guasú o pastel de choclo, mbaipy, chipá mbocá o chipá caburé and some other similar meals that have as basis:manioc, corn, cheese and, sometimes, some meat.. Chipá from Cassava is often eaten during breakfast with yerba mate, prepared with hot water, or with café con leche. Sopa Paraguaya and pastel/Carta de Choclo are eaten for lunch or dinner. As regards products made with sugar, Papaya (mamón in Argentine Spanish) jam is typical of the north of this region.
The principal product of this region is certainly yerba mate. Consumed countrywide, this product features a peculiarity of its own in this area: it is not only prepared with hot water but, driven by the region\'s high temperatures, it is common to see it prepared with cold water as well, in which case the beverage is known as tereré.
### Patagonia
The large southern region of Patagonia is made up of the provinces Neuquén, Río Negro, Chubut, Santa Cruz and Tierra del Fuego. This area also includes the Antarctica and Islas del Atlántico Sur. (or southern atlantic islands). Their most typical food ingredients include fish and seafood from the sea and rivers and the products of the sheep that are widely farmed there.
Marine species such as salmon, spider crabs, squid and other shellfish and molluscs may be caught in the Atlantic Ocean. There are trout in the rivers.
The many berries grown in the area include cherries, bilberries, strawberries, rosa mosqueta and elders, which are made into jams.
The Northern and Central European settlements in this region have built up large-scale production of chocolate and its by-products. Viennese and German cuisine and pastries are also typically associated with this region.
Mutton and lamb, together with wild boar and venison tend to make up the region\'s meat-based dishes. Also typical of the southern region are smoked products, including salmon, stag, wild boar, and pheasant.
Patagonia has been profoundly influenced by the tribes living there since long before Europeans arrived, in particular, the Mapuches and the Araucanos. A typical dish prepared by the latter is the curanto (a term meaning \"hot stone\"). Its preparation involves making a fire in a hole about 150 cm deep in the ground, and heating stones in it. A bed of nalca or maqui leaves is arranged on top of the stones, and ingredients are added in turn on top. Ingredients vary, but may include beef, lamb, pork, chicken, Argentine chorizos (pork sausages), potatoes, sweet potatoes, apples and holed squashes filled with cheese, cream and peas. The food is covered with leaves and damp pieces of cloth to keep the heat in, and covered with plenty of soil.
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# Argentine cuisine
## Alcoholic beverages {#alcoholic_beverages}
Though wine (*vino*) has traditionally been the most popular alcoholic beverage in Argentina, beer (*cerveza*; the Italian *birra* is frequently used) in recent decades has competed with wine in popularity. Breweries appeared in Argentina at the end of the 1860s, started by Alsatian colonists. The first were nearly all in the downtown of Buenos Aires (*el égido de la Ciudad Autónoma de Buenos Aires*), and soon Polish brewers began industrial production of beer: San Carlos in the province of Santa Fe, Río Segundo and Córdoba in the province of Córdoba, Quilmes and Llavallol on the outskirts of La Plata (in Buenos Aires Province), San Miguel de Tucumán in the province of Tucumán and on the outskirts of the cities of Mendoza and Salta.
The local consumption of beer has risen dramatically in the last generation: Argentines consumed 233 million litres in 1980 and 1.57 billion in 2007 (40 litres per capita). Outpacing that of wine since 2001, the growing production and consumption of beer have supported the existence of related events, for example, beer festivals called *Oktoberfests* or \"*Fiestas de la Cerveza*\" in locations that have a significant German population (Villa General Belgrano in Córdoba, San Carlos and Esperanza in the province of Santa Fe, etc.). Such celebrations copy, in an Argentine manner, Munich\'s *Oktoberfest*, and similarly are tourist attractions. However, the presence of a vigorous population of Celtic lineage, principally of Irish origin, has supported the creation of other celebrations of beer, often for marketing purposes, such as Saint Patrick\'s Day (*Día de San Patricio*), patron of Ireland, which is celebrated with abundant libations.
The consumption of alcoholic beverages in Argentina is similar to that of the United States and somewhat lower than the Western European average. Argentines enjoy a variety of alcoholic beverages and Argentina can boast a varied array of *elaboraciones*, whether industrial or artisanal. Besides beer and wine, Argentines frequently drink cider (here again, the heritage comes from Spain and Italy, more precisely from Asturias and Campania). Cider is the most popular beverage of the middle and lowers economic classes at Christmas and New Year (the upper classes proverbially preferring to celebrate with locally produced champagne, although real old-line \"creole\" aristocrats will still drink cider, which is much more traditional).
Other widely consumed spirits are *aguardiente* (firewater) made from sugar cane, known as *caña quemada* (\"burnt cane\") or, simply, **\'caña**\' (\"cane\"). A folkloric note about *caña quemada*: until 21 June it is traditional to drink *caña quemada* with *ruda macho* (a variant of common rue), it is supposed that this mixture prevents the flu and other illnesses. *Caña* competes, mainly in rural areas, with gin (\"ginebra\"---as in the Dutch kind of gin.)
The bitter spirit Fernet, and particularly the Italian brand Fernet-Branca, is highly popular in Argentina. (A study in 2017 found that Argentines consume more than 75% of all fernet produced globally.) Fernet is most commonly enjoyed as a mixed drink with Coca-Cola. Given Fernet\'s qualities as a digestive aid, it is a common choice for an after-dinner digestif.
There are many artisanally produced liqueurs (distilled, flavoured alcoholic beverages) in Argentina, for example, those flavoured with orange, egg, anise, coffee, cherry and, inevitably, *dulce de leche*. The *Hesperidina* is a type of vermouth made from orange peels, invented in Argentina around 1890. One may also encounter *chitronchelo* or (in Italian) *citronella*, based on lemon. This beverage arrived with immigrants from the Mezzogiorno and is produced both artisanally and industrially (for example, at Mar del Plata).
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# Argentine cuisine
## Non-alcoholic specialties {#non_alcoholic_specialties}
Argentines enjoy a wide variety of non-alcoholic infusions (although now and then both \"families\" are mixed; the *yerbiao* for example, is mate mixed with *caña* or gin). Among these, *mate* has long been the most widely enjoyed; in 2006, over 700,000 metric tons were harvested in Argentina, mostly for domestic consumption. Mate is also one of the top exports from Argentina, as it is valued all over the world.
The fact that mate is so prevalent in the Southern Cone, however, should not necessarily make visitors think that other infusions are rare in the region; in Argentina especially, given the strong European cultural imprint, the consumption of coffee is very common (141 cups per capita, annually). Chocolate infusions are also popular (the eating of chocolate is a Spanish influence, although the plant originated in Mesoamerica). This consumption grows during autumn and winter, or in the cold regions of the country; there are two dates where consumption of chocolate infusions is traditional in the primary educational centres: 25 May and 9 July, that is, the two national dates of Argentina.
English cultural influence (reinforced at the end of the 19th century and the beginnings of the 20th by British contacts with the Far East) has also made the consumption of tea very common.
Medicinal herbs are common in the whole country; among the most popular are: chamomile, lanceleaf, *boldo*, *poleo*, *peperina*, *carqueja*, thyme, *canchalagua*, rue (*macho* and *hembra*, that is, \"male\" and \"female\"), mallow, rosemary, passion flower, *bira bira*, *palán palán*, *muña muña*, to mention only the main ones. Many of these herbs are also used in apéritifs and bitters, whether alcoholic or not.
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# Argentine cuisine
## Popular short-order dishes {#popular_short_order_dishes}
Common *restoranes* or *restaurantes* and *rotiserias* (grill restaurants) nearly anywhere in Argentina today serve (into the small hours) quickly prepared meals that in the course of the 20th century came to be known as *minutas*, \"short-order dishes\". Some of the dishes included in the category of *minutas* are *milanesas*, *churrascos*, *bifes* (beefsteaks), *escalopes*, *tallarines*, *ravioles* (ravioli), *ñoquis* (gnocchi), although some are very typical of locations that sell food: \"*bifes*\" and \"*milanesas*\" are served \"*a caballo*\" (\"on horseback\", with fried egg on top), \"*milanesa completa*\" (a *milanesa* with two fried eggs and French fries), \"*revuelto Gramajo*\", \"*colchón de arvejas*\" (an omelette made with peas), \"*suprema de pollo*\" (chicken supreme, usually breaded as a *milanesa*), *matambres*, \"*lengua a la vinagreta*\" (pickled tongue), and \"sandwiches\" (*sandwiches de miga*) are made with sliced white bread, rather than, say, rolls.
The most common sandwiches are those made of *milanesa*, baked ham and cheese, *pan de miga*, toast, *pebetes*, *panchos* (hot dogs), *choripanes*, *morcipanes*, etc.; from Montevideo comes a different species of sandwich called the *chivito*, even though it contains no goat meat.
*Picadas*, which are consumed at home or in bars, cafés, \"*cafetines*\" and \"*bodegones*\" are also popular; they consist of an ensemble of plates containing cubes of cheese (typically from Mar del Plata or Chubut), pieces of salame, olives in brine, french fries, *maníes* (peanuts), etc.; *picada*s are eaten accompanied by an alcoholic beverage (\"*fernet*\", beer, wine with soda, to give some common examples).
The people of Argentina greatly enjoy *helado* (ice creams of Italian lineage or sorbets Spanish lineage). In Spanish colonial times, a type of sorbet was made from hail or snow.
<File:Picadacordobesa.JPG%7CA> *picada*, the Italian-influenced between-meals standby
## Eating habits {#eating_habits}
Breakfast typically is small and consists of coffee (or mate) and pastry. In most parts of Argentina, lunch is the largest meal of the day. Excluding the largest cities, such as Buenos Aires, Rosario or Cordoba, most towns close for lunchtime. This is when most people return home to enjoy a large meal and siesta. Traditional lunches in Argentina are long and well developed. Argentines often have a light evening snack (called a \"merienda\" -- typically a coffee or mate and a pastry) and it is common to not eat dinner until 9 at night, or even later on weekends
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# Analysis of algorithms
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# Ælle of Sussex
**Ælle** (also **Aelle** or **Ella**) is recorded in much later medieval sources as the first king of the South Saxons, reigning in what is now called Sussex, England, from 477 to perhaps as late as 514.
According to the *Anglo-Saxon Chronicle*, Ælle and three of his sons are said to have landed at a place called Cymensora and fought against the local Britons. The *Chronicle* goes on to report a victory dated to 491 at Anderitum (present day Pevensey Castle) where the battle ended with the Saxons slaughtering their Brittonic opponents to the last man.
Ælle was the first king recorded by the 8th century chronicler Bede to have held \"*imperium*\", or overlordship, over other Anglo-Saxon kingdoms. In the late 9th-century *Anglo-Saxon Chronicle* (around four hundred years after his time) Ælle is recorded as being the first bretwalda, or \"Britain-ruler\", though there is no evidence that this was a contemporary title. Ælle\'s death is not recorded and although he may have been the founder of a South Saxon dynasty, there is no firm evidence linking him with later South Saxon rulers. The 12th-century chronicler Henry of Huntingdon produced an enhanced version of the *Anglo-Saxon Chronicle* that included 514 as the date of Ælle\'s death, but this is not secure.
## Historical context {#historical_context}
Historians are divided on the detail of Ælle\'s life and existence as it was during the least-documented period in English history of the last two millennia.
By the early 5th century, Britain had been Roman for over three hundred and fifty years. Amongst the enemies of Roman Britain were the Picts of central and northern Scotland, and the Gaels known as Scoti, who were raiders from Ireland. Also vexatious were the Saxons, the name Roman writers gave to the peoples who lived in the northern part of what is now Germany and the southern part of the Jutland peninsula. Saxon raids on the southern and eastern shores of England had been sufficiently alarming by the late 3rd century for the Romans to build the Saxon Shore forts, and subsequently to establish the role of the Count of the Saxon Shore to command the defence against these incursions. Roman control of Britain finally ended in the early part of the 5th century; the date usually given as marking the end of Roman Britain is 410, when the Emperor Honorius sent letters to the British, urging them to look to their own defence. Britain had been repeatedly stripped of troops to support usurpers\' claims to the Roman empire, and after 410 the Roman armies never returned.
Sources for events after this date are extremely scarce, but a tradition, reported as early as the mid-6th century by a British priest named Gildas, records that the British sent for help against the barbarians to Aetius, a Roman consul, probably in the late 440s. No help came. Subsequently, a British leader named Vortigern is supposed to have invited continental mercenaries to help fight the Picts who were attacking from the north. The leaders, whose names are recorded as Hengest and Horsa, rebelled, and a long period of warfare ensued. The invaders---Angles, Saxons, Jutes, and Frisians---gained control of parts of England, but lost a major battle at Mons Badonicus (the location of which is not known). Some authors have speculated that Ælle may have led the Saxon forces at this battle, while others reject the idea out of hand.
The British thus gained a respite, and peace lasted at least until the time Gildas was writing: that is, for perhaps forty or fifty years, from around the end of the 5th century until midway through the sixth. Shortly after Gildas\'s time, the Anglo-Saxon advance was resumed, and by the late 6th century nearly all of southern England was under the control of the continental invaders.
## Evidence from place names in Sussex {#evidence_from_place_names_in_sussex}
The early dates given in the *Anglo-Saxon Chronicle* for the colonization of Sussex are supported by an analysis of the place names of the region. The strongest evidence comes from place names that end in \"-ing\", such as Worthing and Angmering. These are known to derive from an earlier form ending in \"-ingas\". \"Hastings\" for example, derives from \"Hæstingas\" which may mean \"the followers or dependents of a person named Hæsta\", although others suggest the heavily Romanised region may have had names of Gallo-Roman origin derived from \"-ienses\". From west of Selsey Bill to east of Pevensey can be found the densest concentration of these names anywhere in Britain. There are a total of about forty-five place names in Sussex of this form, but personal names either were not associated with these places or fell out of use.
The preservation of Ælle\'s sons in Old English place names is unusual. The names of the founders, in other origin legends, seem to have British or Latin roots not Old English. It is likely that the foundation stories were actually known before the 9th century, but the annalists manipulated them to provide a common origin for the new regime. The origin stories purported that the British were defeated and replaced by invading Anglo-Saxons arriving in small ships. These stories were largely believed right up to the 19th century, but are now regarded as myths.
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# Ælle of Sussex
## Reign
If the dates given by the *Anglo-Saxon Chronicle* are accurate to within half a century, then Ælle\'s reign lies in the middle of the Anglo-Saxon expansion, and prior to the final conquest of the Britons. It also seems consistent with the dates given to assume that Ælle\'s battles predate Mons Badonicus.This in turn would explain the long gap, of fifty or more years, in the succession of the \"bretwaldas\": if the peace gained by the Britons did indeed hold till the second half of the 6th century, it is not to be expected that an Anglo-Saxon leader should have anything resembling overlordship of England during that time. The idea of a pause in the Anglo-Saxon advance is also supported by the account in Procopius of 6th century migration from Britain to the kingdom of the Franks. Procopius\'s account is consistent with what is known to be a contemporary colonization of Armorica (now Brittany, in France); the settlers appear to have been at least partly from Dumnonia (modern Cornwall), and the area acquired regions known as Dumnonée and Cornouaille. It seems likely that something at that time was interrupting the general flow of the Anglo-Saxons from the continent to Britain.
The dates for Ælle\'s battles are also reasonably consistent with what is known of events in the kingdom of the Franks at that time. Clovis I united the Franks into a single kingdom during the 480s and afterwards, and the Franks\' ability to exercise power along the southern coast of the English channel may have diverted Saxon adventurers to England rather than the continent.
It is possible, therefore, that a historical king named Ælle existed, who arrived from the continent in the late 5th century, and who conquered much of what is now Sussex. He may have been a prominent war chief with a leadership role in a federation of Anglo-Saxon groups fighting for territory in Britain at that time. This may be the origin of the reputation that led Bede to list him as holding overlordship over southern Britain. The battles listed in the *Chronicle* are compatible with a conquest of Sussex from west to east, against British resistance stiff enough to last fourteen years. His area of military control may have extended as far as Hampshire and north to the upper Thames valley, but it certainly did not extend across all of England south of the Humber, as Bede asserts.
The historian Guy Halsall argues that as Ælle immediately preceded a sequence of three contemporaries from the late sixth-century in Bede\'s original list (Ceawlin of Wessex, Æthelberht of Kent, and Rædwald of East Anglia), it is far more likely that Ælle dates to the mid sixth century, and that the *Chronicle* has moved his dates back a century in order to provide a foundation myth for Sussex which puts it chronologically and geographically between the origins of the kingdoms of Kent and Wessex.
## Death and burial {#death_and_burial}
Ælle\'s death is not recorded by the *Chronicle*, which gives no information about him, or his sons, or the South Saxons until 675, when the South Saxon king Æthelwalh was baptized.
It has been conjectured that, as Saxon war leader, Ælle may have met his death in the disastrous battle of Mount Badon when the Britons halted Saxon expansion. If Ælle died within the borders of his own kingdom then it may well have been that he was buried on Highdown Hill with his weapons and ornaments in the usual mode of burial among the South Saxons. Highdown Hill is the traditional burial-place of the kings of Sussex
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# Acadia University
**Acadia University** is a public, predominantly undergraduate university located in Wolfville, Nova Scotia, Canada, with some graduate programs at the master\'s level and one at the doctoral level. The enabling legislation consists of the Acadia University Act and the Amended Acadia University Act 2000.
The Wolfville Campus houses Acadia University Archives and the Acadia University Art Gallery. Acadia offers over 200 degree combinations in the faculties of arts, pure and applied science, professional studies, and theology. The student-faculty ratio is 15:1 and the average class size is 28. Open Acadia offers correspondence and distance education courses. Acadia does have Botanical Gardens known as the Harriet Irving Gardens. These gardens feature plants and trees native to the Acadian forest region.
## History
Acadia began as an extension of Horton Academy in 1828, which was founded in Horton, Nova Scotia, by Baptists from Nova Scotia and Queen\'s College in 1838, who will be gathered into the Canadian Baptists of Atlantic Canada (Canadian Baptist Ministries). It was designed to prepare men for the ministry and to supply education for lay members.
In 1838, the Nova Scotia Baptist Education Society founded Queen\'s College (named for Queen Victoria). The college began with 21 students in January 1839. The name \"Queen\'s College\" was denied to the Baptist school, so it was renamed \"Acadia College\" in 1841, in reference to the history of the area as an Acadian settlement. Acadia College awarded its first degrees in 1843 and became Acadia University in 1891, established by the Acadia University Act.
The Granville Street Baptist Church (now First Baptist Church Halifax) has played a supporting role throughout its history. Many individuals who have made significant contributions to Acadia University, including the first president John Pryor, were members of the First Baptist Church Halifax congregation.
In 1851, the power of appointing governors was transferred from the Nova Scotia Baptist Education Society to the Baptist Convention of the Maritime Provinces.
Charles Osborne Wickenden, an architect, and J.C. Dumaresq designed the Central Building, Acadia College, 1878--79.
Clara Belle Marshall, from Mount Hanley, Nova Scotia, became the first woman to graduate from Acadia University in 1879.
In 1891, there were changes in the Act of Incorporation.
Andrew R. Cobb designed several campus buildings including: Raynor Hall Residence, 1916; and Horton House, designed by Cobb in the Georgian style, and built by James Reid of Yarmouth, Nova Scotia, which was opened in 1915 as Horton Academy. Today, Horton Hall is the home of the Department of Psychology and Research and Graduate Studies. In 1967 Emmerson Hall was converted to classrooms and offices for the School of Education. It is a registered Heritage Property.
Unveiled on 16 August 1963, a wooden and metal organ in Manning Chapel, Acadia University, is dedicated to Acadia University\'s war dead of the First and Second World Wars and the Korean War. A book of remembrance in Manning Chapel, Acadia University was unveiled on 1 March 1998 through the efforts of the Wolfville Historical Society.
In 1966, it terminated its affiliation with the Canadian Baptists of Atlantic Canada (Canadian Baptist Ministries). The denomination maintains nine seats on the university\'s Board of Governors.
Acadia is a laureate of Washington\'s Smithsonian Institution and a part of the permanent research collection of the National Museum of American History. Acadia is also the only Canadian university selected for inclusion in the Education and Academia category of the Computerworld Smithsonian Award.
### Faculty strikes {#faculty_strikes}
Acadia University\'s Board of Governors and members of the Acadia University Faculty Association (AUFA) have ratified a new collective agreement covering the period 1 July 2010 to 30 June 2014. The faculty of Acadia University have been on strike three times in the history of the institution. The first was 24 February to 12 March 2004. The second was 15 October to 5 November 2007. The second strike was resolved after the province\'s labour minister, Mark Parent, appointed a mediator, on 1 November, to facilitate an agreement. The third strike began on 1 February 2022 and ended 1 March 2022 with both sides agreeing to binding arbitration.
## Academics
### Rankings
In *Maclean\'s* 2023 Guide to Canadian Universities, Acadia was ranked fifth in the publication\'s \"primarily undergraduate\" Canadian university category, tied with Bishop\'s University. In the same year, the publication ranked Acadia 33rd, in Maclean\'s reputation survey.
### Faculties
Acadia is organized into four faculties: Arts, Pure & Applied Science, Professional Studies and Theology. Each faculty is further divided into departments and schools specialized in areas of teaching and research.
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# Acadia University
## Research
Acadia has over 15 research centres and 6 research chairs. Undergraduate students have the opportunity to participate in many research opportunities in a small university setting.
The Division of Research & Graduate Studies is separate from the faculties and oversees graduate students as well as Acadia\'s research programs.
Acadia\'s research programs explore coastal environments, ethno-cultural diversity, social justice, environmental monitoring and climate change, organizational relationships, data mining, the impact of digital technologies, and lifestyle choices contributing to health and wellness. Acadia\'s research centres include the Tidal Energy Institute, the Acadia Institute for Data Analytics, and the Beaubassin Field Station. Applied research opportunities include research with local wineries and grape growers, alternative insect control techniques and technologies.
## Innovation
### Acadia Advantage {#acadia_advantage}
In 1996, Acadia University introduced a new initiative. Named the Acadia Advantage, it integrated the use of notebook computers into the undergraduate curriculum and featured innovations in teaching. By 2000, all full-time, undergraduate Acadia students were taking part in the initiative. The initiative went beyond leasing notebook computers to students during the academic year, and included training, user support and the use of course-specific applications at Acadia.
Acadia is a laureate of Washington\'s Smithsonian Institution and a part of the permanent research collection of the National Museum of American History. It is the only Canadian university selected for inclusion in the Education and Academia category of the Computerworld Smithsonian Award.
In addition, Acadia University received the Pioneer Award for Ubiquitous Computing. In 2001, it achieved high rankings in the annual *Maclean\'s* University Rankings, including Best Overall for Primarily Undergraduate University in their opinion survey, and it received the Canadian Information Productivity Award in 1997 as the first university in Canada to fully utilize information technology in the undergraduate curriculum.
In September 2008, Acadia moved to a student-owned notebook computer version of the Acadia Advantage, now named Acadia Advantage 2.0.
The new Agri-Technology Access Centre in the Innovation Pavilion provides companies and industry organizations with access to specialized technology, lab space, subject-matter expertise and commercialization support services. It also enables Acadia to advance its applied research strength in a priority sector -- agriculture -- and expand its technology transfer and commercialization activities. The Science Complex renewal project was supported by an investment of \$15.98 million by the Federal and Provincial governments.
## Athletics
Acadia\'s sports teams are called the Axemen and Axewomen. They participate in the Atlantic University Sports conference of U Sports.
Men\'s and women\'s varsity teams that have won more conference and national championships than any other institution in Atlantic University Sport. Routinely, more than one-third of Acadia\'s varsity athletes also achieve Academic All-Canadian designation through Canadian Interuniversity Sport by maintaining a minimum average of 80 per cent.
In September 2006, Acadia University announced its partnership with the Wolfville Tritons Swim Club and the Acadia Masters Swim Club to form the Acadia Swim Club and return competitive swimming to the university after a 14-year hiatus. On 26 September 2008, the university announced its intention to return swimming to a varsity status in September 2009.
## Fight song {#fight_song}
Notable among a number of songs commonly played and sung at various events such as commencement, convocation, and athletic games are: *Stand Up and Cheer*, the Acadia University fight song. According to \'Songs of Acadia College\' (Wolfville, NS 1902--3, 1907), the songs include: \'Acadia Centennial Song\' (1938); \'The Acadia Clan Song\'; \'Alma Mater - Acadia;\' \'Alma Mater Acadia\' (1938) and \'Alma Mater Song.\'
## Symbols
In 1974, Acadia was granted a coat of arms designed by the College of Arms in London, England. The coat of arms is two-tone, with the school\'s official colours, garnet and blue, on the shield. The axes represent the school\'s origins in a rural setting, and the determination of its founders who cleared the land and built the school on donated items and labour. The open books represent the intellectual pursuits of a university, and the wolves heads are a whimsical representation of the university\'s location in Wolfville. \"In pulvere vinces\" (In dust you conquer) is the motto.
The university seal depicts the Greek goddess of wisdom Athena in front of the first college hall.
The university also uses a stylized \"A\" as a logo for its sports teams.
Notable among a number of fight songs commonly played and sung at various events such as commencement, convocation, and athletic games are: the Acadia University alma mater set to the tune of \"Annie Lisle\". The lyrics are: `{{block indent|1=<poem>
Far above the dykes of Fundy
And its basin blue
Stands our noble alma mater
Glorious to view
Lift the chorus
Speed it onward
Sing it loud and free
Hail to thee our alma mater
Acadia, hail to thee
Far above the busy highway
And the sleepy town
Raised against the arch of heaven
Looks she proudly down
</poem>}}`{=mediawiki}
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# Acadia University
## Historic buildings {#historic_buildings}
Seminary House, also known as just \"Sem\", is a Second Empire style-building constructed in 1878 as a home for women attending the university. It was designated a National Historic Site of Canada in 1997 as Canada\'s oldest facility associated with the higher education of women. The building now serves as a co-ed residence, and Whitman House on campus now serves as the women\'s only residence.
Carnegie Hall, built in 1909, is a large, two-storey, Neo-classical brick building. It was designated under the provincial Heritage Property Act in 1989 as its construction in 1909 signified Acadia\'s evolution from classical college to liberal university.
The War Memorial House (more generally known as Barrax or Rax), which is a residence, and War Memorial Gymnasium are landmark buildings on the campus of Acadia University. The Memorial Hall and Gymnasium honours students who had enlisted and died in the First World War, and in the Second World War. Two granite shafts, which are part of the War Memorial Gymnasium complex at Acadia University, are dedicated to the university\'s war dead. The War Memorial House is dedicated to the war dead from Acadia University during the Second World War.
## Student life {#student_life}
At Acadia University, students have access to the Student Union Building which serves as a hub for students and houses many Student Union organizations. The building houses The Axe Lounge, a convenience store, an information desk, two food outlets, and the Sexual Health Resource Centre. The university press, *The Athenaeum* is a member of CUP.
### Student government {#student_government}
All students are represented by the Acadia Students\' Union.
### Residences
Approximately 1500 students live on-campus in 11 residences:
- Chase Court
- Chipman House
- Christofor Hall
- Crowell Tower (13 Story High-rise)
- 55 University Avenue (formerly known as Cutten House, it was temporarily renamed in late 2024 until a new name could be decided. Cutten House was named in honour of a university president who had been in support of segregation and eugenics)
- Dennis House - First floor houses student health services
- Eaton House
- Roy Jodrey Hall
- Seminary House - Also houses the School of Education in lower level
- War Memorial (Barrax) House
- Whitman House (Tully) - All female residence
- Willett House (former residence)
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# Acadia University
## People
### List of presidents and vice chancellors {#list_of_presidents_and_vice_chancellors}
- John Pryor, 1846--1850
- John Cramp, 1851--1853 (and 1856--1869)
- Edmund Crawley, 1853--1856
- John Cramp, 1856--1869
- Artemas Wyman Sawyer, 1869--1896
- Thomas Trotter, 1897--1906
- W.B. Hutchinson, 1907--1909
- George Barton Cutten, 1910--1922
- Frederic Patterson, 1923--1948
- Watson Kirkconnell, 1948--1964
- James Beveridge, 1964--1978
- Allan Sinclair, 1978--1981
- James Perkin, 1981--1993
- Kelvin Ogilvie, 1993--2004
- Gail Dinter-Gottlieb, 2004--2008
- Tom Herman (Acting President), 2008--2009
- Ray Ivany, 2009 -- 2017
- Peter J Ricketts, 2017 -- 2023
- Jeffrey J Hennessy, 2023
### List of chancellors {#list_of_chancellors}
- Alex Colville, 1981--1991
- William Feindel, 1991--1996
- Arthur Irving, 1996--2010
- Libby Burnham, 2011--2018
- Bruce Galloway, 2018--2024
- Nancy McCain, 2024--present
### Notable alumni {#notable_alumni}
- Edgar Archibald, scientist and politician
- Norman Atkins, Canadian senator
- Solomon Adeniyi Babalola - Nigerian Baptist missionary/evangelist, Church Pastor, Church Administrator, Denominational Leader, and Theological Educator
- Ron Barkhouse, MLA for Lunenburg East (Horton Academy)
- Gordon Lockhart Bennett, Lieutenant-Governor of Prince Edward Island
- Arthur Bourns, President of McMaster University
- Libby Burnham, lawyer, Chancellor of Acadia University
- Bob Cameron, football player
- Dalton Camp, journalist, politician and political strategist
- M. Elizabeth Cannon, University of Calgary President & Vice-Chancellor
- Lillian Chase, physician
- Paul Corkum, physicist and F.R.S.
- John Wallace de Beque Farris, Canadian senator
- Mark Day, actor
- Michael Dick, CBC-TV journalist
- Charles Aubrey Eaton (1868--1953), clergyman and politician
- William Feindel, neurosurgeon
- Dale Frail, astronomer
- Rob Ramsay, actor
- Alexandra Fuller, writer
- Gary Graham, musician, choral conductor
- Matthew Green, Member of Parliament
- Milton Fowler Gregg, VC laureate, politician
- Robbie Harrison, Nova Scotian politician and educator
- Richard Hatfield, Premier of New Brunswick
- Charles Brenton Huggins, Nobel Laureate
- Kenneth Colin Irving, industrialist
- Robert Irving, industrialist
- Ron James, comedian
- Lorie Kane, LPGA golfer
- Gerald Keddy, Member of Parliament
- Joanne Kelly, actress
- Mary Knickle, composer, lyricist, musician
- Kenneth Komoski, educator
- David H. Levy, astronomer
- Peter MacKay, lawyer, Canadian Minister of National Defense
- Henry Poole MacKeen, Lieutenant-Governor of Nova Scotia
- Paul Masotti, football player
- Harrison McCain, industrialist
- Donald Oliver, Canadian senator
- Rev. William Pearly Oliver, black minister and educator
- Henry Nicholas Paint (1830--1921), member of Parliament, merchant, landowner,
- Freeman Patterson, photographer, writer
- Robert Pope, visual artist author
- Keith R. Porter, cell biologist
- Heather Rankin, singer-songwriter, member of The Rankin Family
- Perry F. Rockwood, radio evangelist
- Erin Roger, scientist
- Jacob Gould Schurman, President of Cornell University
- Roger Tomlinson (1933--2014), geographer and \"The Father of GIS\"
- Rev. William A
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# Steel-string acoustic guitar
The **steel-string acoustic guitar** is a modern form of guitar that descends from the gut-strung Romantic guitar, but is strung with steel strings for a brighter, louder sound. Like the modern classical guitar, it is often referred to simply as an **acoustic guitar**, or sometimes as a **folk guitar**.
The most common type is often called a flat top guitar, to distinguish it from the more specialized archtop guitar and other variations.
The standard tuning for an acoustic guitar is E-A-D-G-B-E (low to high), although many players, particularly fingerpickers, use alternate tunings (scordatura), such as open G (D-G-D-G-B-D), open D (D-A-D-F`{{music|sharp}}`{=mediawiki}-A-D), drop D (D-A-D-G-B-E), or D-A-D-G-A-D (particularly in Irish traditional music).
## Construction
Steel-string guitars vary in construction and materials. Different woods and approach to bracing affect the instrument\'s timbre or tone. While there is little scientific evidence, many players and luthiers believe a well-made guitar\'s tone improves over time. They theorize that a decrease in the content of hemicellulose, crystallization of cellulose, and changes to lignin over time all result in its wood gaining better resonating properties.
### Types
Steel-string acoustic guitars are commonly constructed in several body types, varying in size, depth, and proportion. In general, the guitar\'s soundbox can be thought of as composed of two mating chambers: the *upper bouts* (a *bout* being the rounded corner of an instrument body) on the neck end of the body, and *lower bouts* (on the bridge end). These meet at the *waist,* or the narrowest part of the body face near the soundhole. The proportion and overall size of these two parts helps determine the overall tonal balance and \"native sound\" of a particular body style -- the larger the body, the louder the volume.
- The *parlor*, *00*, *double-O*, or *grand concert* body type is the major body style most directly derived from the classical guitar. It has the thinnest soundbox and the smallest overall size, making it very comfortable to play but lacking in volume projection relative to the larger types. Its smaller size makes it suitable for younger or smaller-framed players. It is well-suited to smaller rooms. Martin\'s 00-xxx series and Taylor\'s x12 series are common examples.
- The *grand auditorium* guitar, sometimes called the *000* or the *triple-O* is very similar in design to the grand concert, but slightly wider and deeper. Many 000-style guitars also have a convex back to increase the physical volume of the soundbox without making it deeper at the edges, which would affect comfort and playability. The result is a very balanced tone, comparable to the 00 but with greater volume and dynamic range and slightly more low-end response, making this body style very popular. Eric Clapton\'s signature Martin, for example, is of this style. Martin\'s 000-xxx series and Taylor\'s x14 series are well-known examples of the grand auditorium style.
- The *dreadnought* is a large-bodied guitar which incorporates a deeper soundbox, but a smaller and less-pronounced upper bout than most styles. Its size and power gave rise to its name, taken from the most formidable class of warship at the time of its creation in the early 20th century. The style was designed by C. F. Martin & Company. to produce a deeper sound than \"classic\"-style guitars, with very resonant bass. Its body\'s combination of compact profile with a deep sound has since been copied by virtually every major steel-string luthier, making it the most popular body type. Martin\'s \"D\" series guitars, such as the highly prized D-28, are classic examples of the dreadnought.
- The *jumbo* body type is bigger again than a grand auditorium but similarly proportioned, and is generally designed to provide a deep tone similar to a dreadnought\'s. It was designed by Gibson to compete with the dreadnought, but with maximum resonant space for greater volume and sustain. These come at the expense of being oversized, with a very deep sounding box, and thus somewhat more difficult to play. The foremost example of the style is the Gibson J-200, but like the dreadnought, most guitar manufacturers have at least one jumbo model.
Any of these body type can incorporate a *cutaway*, where a section of the upper bout below the neck is scalloped out. This allows for easier access to the frets located atop the soundbox, at the expense of reduced soundbox volume and altered bracing, which can affect the resonant qualities and resulting tone of the instrument.
All of these relatively traditional looking and constructed instruments are commonly referred to as *flattop* guitars. All are commonly used in popular music genres, including rock, blues, country, and folk.
Other styles of guitar which enjoy moderate popularity, generally in more specific genres, include:
- The *archtop*, which incorporates an arched, violin-like top either carved out of solid wood or heat-pressed using laminations. It usually has violin style f-holes rather than a single round sound hole. It is most commonly used by swing and jazz players and often incorporates an electric pickup.
- The *Selmer-Maccaferri guitar* is usually played by those who follow the style of Django Reinhardt. It is an unusual-looking instrument, distinguished by a fairly large body with squarish bouts, and either a D-shaped or longitudinal oval soundhole. The strings are gathered at the tail like an archtop guitar, but the top is flatter. It also has a wide fingerboard and slotted head like a nylon-string guitar. The loud volume and penetrating tone make it suitable for single-note soloing, and it is frequently employed as a lead instrument in gypsy swing.
- The *resonator guitar*, also called the *Dobro* after its most prominent manufacturer, amplifies its sound through one or more metal cone-shaped resonators. It was designed to overcome the problem of conventional acoustic guitars being overwhelmed by horns and percussion instruments in dance orchestras. It became prized for its distinctive sound, however, and gained a place in several musical styles (most notably blues and bluegrass), and retains a niche well after the proliferation of electric amplification.
- The *12-string guitar* replaces each string with a course of two strings. The lower pairs are tuned an octave apart. Its unique sound was made famous by artists such as Lead Belly, Pete Seeger and Leo Kottke.
### Tonewoods
Traditionally, steel-string guitars have been made of a combination of various *tonewoods*, or woods considered to have pleasing resonant qualities when used in instrument-making. The term is ill-defined and the wood species that are considered tonewoods have evolved throughout history. Foremost for making steel-string guitar tops are Sitka spruce, the most common, and Alpine and Adirondack spruce. The back and sides of a particular guitar are typically made of the same wood; Brazilian rosewood, East Indian rosewood, and Honduras mahogany are traditional choices, however, maple has been prized for the figuring that can be seen when it is cut in a certain way (such as *flame* and *quilt* patterns). A common non-traditional wood gaining popularity is sapele, which is tonally similar to mahogany but slightly lighter in color and possessing a deep grain structure that is visually appealing.
Due to decreasing availability and rising prices of premium-quality traditional tonewoods, many manufacturers have begun experimenting with alternative species of woods or more commonly available variations on the standard species. For example, some makers have begun producing models with red cedar or mahogany tops, or with spruce variants other than Sitka. Cedar is also common in the back and sides, as is basswood. Entry-level models, especially those made in East Asia, often use nato wood, which is again tonally similar to mahogany but is cheap to acquire. Some have also begun using non-wood materials, such as plastic or graphite. Carbon-fiber and phenolic composite materials have become desirable for building necks, and some high-end luthiers produce all-carbon-fiber guitars.
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# Steel-string acoustic guitar
## Construction
### Assembly
The steel-string acoustic guitar evolved from the gut-string Romantic guitar, and because steel strings have higher tension, heavier construction is required overall. One innovation is a metal bar called a truss rod, which is incorporated into the neck to strengthen it and provide adjustable counter-tension to the stress of the strings. Typically, a steel-string acoustic guitar is built with a larger soundbox than a standard classical guitar. A critical structural and tonal component of an acoustic guitar is the bracing, a systems of struts glued to the inside of the back and top. Steel-string guitars use different bracing systems from classical guitars, typically using X-bracing instead of fan bracing. (Another simpler system, called ladder bracing, where the braces are all placed across the width of the instrument, is used on all types of flat-top guitars on the back.) Innovations in bracing design have emerged, notably the A-brace developed by British luthier Roger Bucknall of Fylde Guitars.
Most luthiers and experienced players agree that a good solid top (as opposed to laminated or plywood) is the most important factor in the tone of the guitar. Solid backs and sides can also contribute to a pleasant sound, although laminated sides and backs are acceptable alternatives, commonly found in mid-level guitars (in the range of US\$300--\$1000).
From the 1960s through the 1980s, \"by far the most significant developments in the design and construction of acoustic guitars\" were made by the Ovation Guitar Company. It introduced a composite *roundback* bowl, which replaced the square back and sides of traditional guitars; because of its engineering design, Ovation guitars could be amplified without producing the obnoxious feedback that had plagued acoustic guitars before. Ovation also pioneered with electronics, such as pickup systems and electronic tuners.\* `{{cite news|date=1 October 2004|title=Ovation's encore: How a host of product refinements have rekindled growth at Kaman Music's flagship guitar division|series=The Guitar Market|newspaper=[[The Music Trades]]|access-date=1 May 2012|url=http://www.highbeam.com/doc/1G1-124136480.html|archive-date=28 February 2011|archive-url=https://web.archive.org/web/20110228012553/http://www.highbeam.com/doc/1G1-124136480.html|url-status=dead}}`{=mediawiki}
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## Amplification
A steel-string guitar can be `{{em|amplified}}`{=mediawiki} using any of three techniques:
- a microphone, possibly clipped to the guitar body;
- a detachable pickup, often straddling the soundhole and using the same magnetic principle as a traditional electric guitar; or
- a transducer built into the body.
The last type of guitar is commonly called an *acoustic-electric guitar* as it can be played either \"unplugged\" as an acoustic, or plugged in as an electric. The most common type is a piezoelectric pickup, which is composed of a thin sandwich of quartz crystal. When compressed, the crystal produces a small electric current, so when placed under the bridge saddle, the vibrations of the strings through the saddle, and of the body of the instrument, are converted to a weak electrical signal. This signal is often sent to a pre-amplifier, which increases the signal strength and normally incorporates an equalizer. The output of the preamplifier then goes to a separate amplifier system similar to that for an electric guitar.
Several manufacturers produce specialised acoustic guitar amplifiers, which are designed to give undistorted and full-range reproduction.
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# Steel-string acoustic guitar
## Music and players {#music_and_players}
Until the 1960s, the predominant forms of music played on the flat-top, steel-string guitar remained relatively stable and included acoustic blues, country, bluegrass, folk, and several genres of rock. The concept of playing solo steel-string guitar in a concert setting was introduced in the early 1960s by such performers as Davey Graham and John Fahey, who used country blues fingerpicking techniques to compose original compositions with structures somewhat like European classical music. Fahey contemporary Robbie Basho added elements of Indian classical music and Leo Kottke used a Faheyesque approach to make the first solo steel-string guitar \"hit\" record.
Steel-string guitars are also important in the world of flatpicking, as utilized by such artists as Clarence White, Tony Rice, Bryan Sutton, Doc Watson and David Grier. Luthiers have been experimenting with redesigning the acoustic guitar for these players. These flat-top, steel-string guitars are constructed and voiced more for classical-like fingerpicking and less for chordal accompaniment (strumming). Some luthiers have increasingly focused their attention on the needs of fingerstylists and have developed unique guitars for this style of playing.
Many other luthiers attempt to recreate the guitars of the \"Golden Era\" of C.F. Martin & Co. This was started by Roy Noble, who built the guitar played by Clarence White from 1968 to 1972, and was followed by Bill Collings, Marty Lanham, Dana Bourgeois, Randy Lucas, Lynn Dudenbostel and Wayne Henderson, a few of the luthiers building guitars today inspired by vintage Martins, the pre--World War II models in particular. As prices for vintage Martins continue to rise exponentially, upscale guitar enthusiasts have demanded faithful recreations and luthiers are working to fill that demand
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# Antipope John XXIII
**Baldassarre Cossa** (died 22 December 1419) was Pisan antipope as **John XXIII** (1410--1415) during the Western Schism. The Catholic Church today regards him as an antipope in opposition to Pope Gregory XII, whom it recognizes as the rightful successor of Saint Peter. John XXIII was also an opponent of Benedict XIII, who was recognized by the French clergy and monarchy as the legitimate pope.
Historically, the *Annuario Pontificio* recognized John XXIII the legitimate successor of Saint Peter. However, the Western Schism was reinterpreted in 1958 when Pope John XXIII chose to reuse the ordinal XXIII, which is now reflected in modern editions of the *Annuario Pontificio*. John XXIII is now considered to be an antipope and Gregory XII\'s reign is recognized to have extended until 1415.
Cossa was born in the Kingdom of Naples. In 1403, he served as a papal legate in Romagna. He participated in the Council of Pisa in 1408, which sought to end the Western Schism with the election of a third alternative pope. In 1410, he succeeded Antipope Alexander V, taking the name John XXIII. At the instigation of King Sigismund of Germany, John XXIII called the Council of Constance of 1413, which deposed both John XXIII and Benedict XIII, accepted Gregory XII\'s resignation, and elected Pope Martin V to replace them, thus ending the schism. John XXIII was tried for various crimes, though later accounts question the veracity of those accusations. Towards the end of his life, Cossa restored his relationship with the Church and was made Cardinal Bishop of Frascati by Pope Martin V.
## Early life {#early_life}
Baldassarre Cossa was born on the island of Procida in the Kingdom of Naples, the son of Giovanni Cossa, lord of Procida. Initially he followed a military career, taking part in the Angevin-Neapolitan war. His two brothers were sentenced to death for piracy by Ladislaus of Naples.
He studied law at the University of Bologna and obtained doctorates in both civil and canon law. Probably at the prompting of his family, in 1392 he entered the service of Pope Boniface IX, first working in Bologna and then in Rome. (The Western Schism had begun in 1378, and there were two competing popes at the time, one in Avignon supported by France and Spain, and one in Rome, supported by most of Italy, Germany and England.) In 1386 he is listed as canon of the cathedral of Bologna. In 1396, he became archdeacon in Bologna. He became Cardinal deacon of Saint Eustachius in 1402 and Papal legate in Romagna in 1403. Johann Peter Kirsch describes Cossa as \"utterly worldly-minded, ambitious, crafty, unscrupulous, and immoral, a good soldier but no churchman\". At this time Cossa also had some links with local robber bands, which were often used to intimidate his rivals and attack carriages. These connections added to his influence and power in the region.
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# Antipope John XXIII
## Role in the Western Schism {#role_in_the_western_schism}
### Council of Pisa {#council_of_pisa}
Cardinal Cossa was one of the seven cardinals who, in May 1408, withdrew their allegiance from Pope Gregory XII, stating that he had broken his solemn oath not to create new cardinals without consulting them in advance. In company with those cardinals who had been following Antipope Benedict XIII of Avignon, they convened the Council of Pisa, of which Cossa became a leading figure. The aim of the council was to end the schism; to this end they deposed both Gregory XII and Benedict XIII and elected a new pope Alexander V in 1409. Gregory and Benedict ignored this decision, however, so that there were now three simultaneous claimants to the papacy.
### Election to the papacy {#election_to_the_papacy}
Alexander suddenly died while he was with Cardinal Baldassare Cossa at Bologna on the night of 3--4 May 1410. On 25 May 1410, Cossa was consecrated a pope taking the name John XXIII. He had become an ordained bishop only one day earlier. John XXIII was acknowledged as pope by France, England, Bohemia, Portugal, parts of the Holy Roman Empire, and numerous Northern Italian city states, including Florence and Venice and the Patriarchate of Aquileia; and in the beginning and in 1411--1413 by Hungary and Poland. However, the Avignon Pope Benedict XIII was regarded as pope by the Kingdoms of Aragon, Castile, Sicily and Scotland. Gregory XII was still favored by Ladislaus of Naples, Carlo I Malatesta, the princes of Bavaria, Louis III, Elector Palatine, and parts of Germany and Poland. John XXIII made the Medici Bank the bank of the papacy, contributing considerably to the family\'s wealth and prestige.
The main enemy of John was Ladislaus of Naples, who protected Gregory XII in Rome. Following his election as pope, John spent a year in Bologna and then joined forces with Louis II of Anjou to march against Ladislaus. An initial victory proved short-lived and Ladislaus retook Rome in May 1413, forcing John to flee to Florence. In Florence he met Sigismund, King of the Romans. Sigismund wanted to end the schism and urged John to call a general council. John did so with hesitation, at first trying to have the council held in Italy (rather than in a German Imperial City, as Sigismund wanted). The Council of Constance was convened on 30 October 1414. During the third session, rival Pope Gregory XII authorized the council as well. The council resolved that all three popes should abdicate and a new pope be elected.
### Flight from the Council of Constance {#flight_from_the_council_of_constance}
In March, John escaped from Constance disguised as a postman. According to the Klingenberger Chronicle, written by a noble client of Frederick IV, Duke of Austria, John XXIII traveled down the Rhine to Schaffhausen in a boat, while Frederick accompanied him with a small band of men on horseback. There was a huge outcry in Constance when it was discovered that John had fled, and Sigismund was furious about this setback to his plans for ending the Schism. The King of the Romans issued orders to all the powers on the Upper Rhine and in Swabia stating that he had declared Frederick to be an outlaw and that his lands and possessions were forfeit. In due course this led to a great deal of political upheaval and many Austrian losses in the region, notably in Aargau to the Swiss Confederation.
In the meantime, Antipope John XXIII and Frederick fled further downriver along the Rhine to the town of Freiburg im Breisgau, which recognised the duke of Austria as its lord. There Sigismund\'s lieutenant Ludwig III, Elector Palatine caught up with them. He convinced Frederick that he stood to lose too much by harbouring the fugitive pope, and the Austrian duke agreed to give himself and John up and return to Constance.
### Deposition
During his absence, John was deposed by the council, and upon his return he was tried for heresy, simony, schism and immorality, and found guilty on all counts. The 18th century historian Edward Gibbon wrote, \"The more scandalous charges were suppressed; the vicar of Christ was accused only of piracy, rape, sodomy, murder and incest.\" John was given over to Ludwig III, Elector Palatine, who imprisoned him for several months in Heidelberg and Mannheim.
The last remaining claimant in Avignon, Benedict XIII, refused to resign and was excommunicated. Martin V was elected as new pope in 1417.
## Death and burial {#death_and_burial}
Cossa was freed in 1418 after a heavy ransom was paid by the Medici. He went to Florence, where he submitted to Martin V, who made him Cardinal Bishop of Frascati. Cossa died only a few months later.
The Medici oversaw the construction of his magnificent tomb by Donatello and Michelozzo in the Battistero di San Giovanni in Florence. Pope Martin V protested in vain against the inscription on the sarcophagus: \"John the former pope\".
J.P. Kirsch remarks that \"Undeniably secular and ambitious, his moral life was not above reproach, and his unscrupulous methods in no wise accorded with the requirements of his high office \... the heinous crimes of which his opponents in the council accused him were certainly gravely exaggerated.\" One historian concluded that John was \"a great man in temporal things, but a complete failure and worthless in spiritual things\".
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# Antipope John XXIII
## Fictional depictions {#fictional_depictions}
John is portrayed by Steven Waddington in the 2016 television series *Medici: Masters of Florence*.
The 1932 thriller *Safe Custody* by Dornford Yates, references John. Listing the members of an objectionable family, a character in the story says, \"Then we come to his nephew---a promising lad of fifteen. He lies, steals, smells, assaults the servants and abuses any animal which he is satisfied will not retaliate. If Gibbon may be believed, Pope John the Twenty-third as a stripling must have resembled him\".
In 1983, American political satirist and novelist Richard Condon wrote *A Trembling Upon Rome*, a novel of historical fiction about the life of Baldassare Cossa.
Russian writer Dmitry Balashov wrote the novel *Baltazar Kossa* (*Бальтазар Косса*) about Antipope John XXIII.
## Numbering issues {#numbering_issues}
He should not be confused with Pope John XXIII of the twentieth century. When Angelo Roncalli was elected pope in 1958, there was some confusion as to whether he would be *John XXIII* or *John XXIV*; he then declared that he was John XXIII to put this question to rest. There was no John XX, since that number was skipped due to an error by Medieval Pope John XXI; this is why Gibbon refers to the antipope John as John XXII
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# Cobble Hill Tunnel
The **Cobble Hill Tunnel** (also known as the **Atlantic Avenue Tunnel**) is an abandoned Long Island Rail Road (LIRR) tunnel beneath Atlantic Avenue in Brooklyn, New York City, running through the neighborhoods of Downtown Brooklyn and Cobble Hill. When open, it ran for about 2517 ft between Columbia Street and Boerum Place. It is the oldest railway tunnel beneath a city street in North America that was fully devoted to rail. It is also deemed the oldest subway tunnel in the world by the *Guinness Book of World Records*.
## Construction and operation {#construction_and_operation}
Originally built as an open cut, construction began in May 1844, and opened for use on December 3, 1844, but was not completely finished until mid-1845. It was built mainly to satisfy public demand for creation of a grade-separated right of way for the Brooklyn and Jamaica Railroad (later Long Island Rail Road) on its way to the South Ferry at the foot of Atlantic Street (later Atlantic Avenue), where passengers could catch ferries to Manhattan. The construction of the cut also lowered the LIRR\'s grade through Cobble Hill. Around five years after opening the cut was roofed over, converting it into a tunnel. As originally built, the cut was 21 ft wide and 2517 ft long. Once roofed over, the interior height of the newly created tunnel was 17 ft.
In exchange for building the cut, the City of Brooklyn granted the B&J permission to operate its steam locomotives on Atlantic Street west of Fifth Avenue (then Parmentier\'s Garden/Gowanus Lane), all the way to Brooklyn\'s South Ferry (the present location of Brooklyn\'s Pier 7). Prior to the cut being built, the LIRR\'s western terminus was Atlantic Street at Clinton Street. Train cars were hauled by teams of horses along Atlantic Street from Clinton Street to Parmentier\'s Garden, where steam locomotives were attached. While the cut was being built, the railroad operated to a temporary terminal at Pacific Street and Henry Street.
The Cobble Hill Tunnel was part of the first rail link between New York City and Boston, Massachusetts. The railroad connected Lower Manhattan via the South Ferry to Greenport on the North Fork of Long Island; a ferry connected Greenport to Stonington, Connecticut, where a rail link continued to Boston. This avoided some difficult construction of bridges over the rivers of southern Connecticut. In 1848, the New York and New Haven Railroad Line was completed through Connecticut, providing a direct, faster rail connection from New York City to Boston. The Cobble Hill Tunnel and the Long Island Railroad remained the primary means of access to most of central Long Island from Manhattan and New York City.
The ends of the tunnel were sealed in the fall of 1861. The similar Murray Hill Tunnel on the New York and Harlem Railroad was built as an open cut around 1836, roofed over around the 1850s, and is now in use for automobile traffic.
## Closure controversy {#closure_controversy}
In 1861, the New York State Legislature voted to ban railroad locomotives from within the limits of the City of Brooklyn. A tax assessment was ordered on all property owners along Atlantic Street (today Atlantic Avenue), to defray the costs of the closure. It was undisclosed at the time that New York State Governor John A. King was a major shareholder in the Brooklyn and Jamaica Railroad (later the Long Island Rail Road) and therefore had a conflict of interest and stood to benefit by the compensation payments to the railroad from the tax assessment.
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# Cobble Hill Tunnel
## Dormancy
Walt Whitman wrote of the tunnel:
> The old tunnel, that used to lie there under ground, a passage of Acheron-like solemnity and darkness, now all closed and filled up, and soon to be utterly forgotten, with all its reminiscences; however, there will, for a few years yet be many dear ones, to not a few Brooklynites, New Yorkers, and promiscuous crowds besides. For it was here you started to go down the island, in summer. For years, it was confidently counted on that this spot, and the railroad of which it was the terminus, were going to prove the permanent seat of business and wealth that belong to such enterprises. But its glory, after enduring in great splendor for a season, has now vanished---at least its Long Island Railroad glory has. The tunnel: dark as the grave, cold, damp, and silent. How beautiful look earth and heaven again, as we emerge from the gloom! It might not be unprofitable, now and then, to send us mortals---the dissatisfied ones, at least, and that\'s a large proportion---into some tunnel of several days\' journey. We\'d perhaps grumble less, afterward, at God\'s handiwork.
In March 1916, the Bureau of Investigation suspected German terrorists were making bombs in the tunnel, and broke through the roof of the tunnel with jackhammers. They found nothing, installed an electric light, and resealed it. In the 1920s, it was rumored to be used for both mushroom growing and bootleg whiskey stills, even though there was no access into the main portion of the tunnel. It became an object of local folklore and legend. In 1936, the New York City Police Department unsuccessfully attempted to enter the tunnel, in order to look for the body of a hoodlum supposedly buried there. In 1941, it was rumored to have been inspected by the federal Works Progress Administration to determine its structural strength, but there is no evidence of this. A few years later, it was once again rumored to have been opened, this time by the FBI, in an unsuccessful search for spies; however, there is no evidence of this. During the late 1950s, it was sought by two rail historians, George Horn and Martin Schachne, but they did not gain access to the tunnel itself.
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# Cobble Hill Tunnel
## Rediscovery
Having fallen from public notice, the tunnel was rediscovered in 1980 by then 20-year-old Bob Diamond, who entered from a manhole he located at Atlantic Avenue and Court Street, crawled a distance of 70 ft underground through a filled-in section of tunnel less than 2 ft high, and located the bulkhead wall that sealed off the main portion of the tunnel. With the assistance of a Brooklyn Union Gas Company engineering crew, he then broke through the massive concrete bulkhead wall, which is several feet thick. Diamond thereby opened access to the main portion of the tunnel, and began to popularize the tunnel as an antiquity. He led tours of its interior for his Brooklyn Historic Railway Association, from 1982 until December 17, 2010, when the Department of Transportation terminated his contract, citing safety concerns. The tunnel has been listed on the National Register of Historic Places since 1989.
The History Channel series *Cities of the Underworld* ran a segment (\"New York\'s Secret Societies\") on the tunnel in 2008
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# Annapolis Valley
The **Annapolis Valley** is a valley and region in the province of Nova Scotia, Canada. It is located in the western part of the Nova Scotia peninsula, formed by a trough between two parallel mountain ranges along the shore of the Bay of Fundy. Statistics Canada defines the Annapolis Valley as an economic region, composed of Annapolis County, Kings County, and Hants County.
## Geography
The valley measures approximately 126 km in length from Annapolis Royal and the Annapolis Basin in the west to Wolfville and the Minas Basin in the east, spanning the counties of Digby, Annapolis and Kings.
Some also include the western part of Hants County, including the towns of Hantsport and Windsor even further to the east, but geographically speaking they are part of the Avon River valley.
The steep face of basaltic North Mountain shelters the valley from the adjacent Bay of Fundy and rises over 260 m in elevation near Lawrencetown. The granitic South Mountain rises to a somewhat higher elevation and shelters the valley from the climate of the Atlantic Ocean approximately 100 kilometres further south on the province\'s South Shore.
The shelter provided by these two mountainous ridges has produced a microclimate which provides relatively mild temperatures for the region and, coupled with the fertile glacial sedimentary soils on the valley floor, the region is conducive to growing vegetable and fruit crops. Particularly famous for its apple crop, the valley hosts in excess of 1,000 farms of various types, the majority being relatively small family-owned operations.
Within the valley itself are two major rivers, the Annapolis River which flows west from Caribou Bog in the central part of the valley into Annapolis Basin, and the Cornwallis River which flows east from Caribou Bog into Minas Basin. The North Mountain ridge forms the north side of the Annapolis Valley. Also flowing east, in two smaller valleys north of the Cornwallis River, are the Canard River and the Habitant River, both of which also flow into the Minas Basin.
## History
Long settled by the Mi\'kmaq nation, the valley experienced French settlement at the Habitation at Port-Royal, near modern-day Annapolis Royal in the western part of the valley, beginning in 1605. From there, the Acadians spread throughout the Valley, in various communities, building dykes to claim the tidal lands along the Annapolis and Cornwallis Rivers. They continued throughout the Annapolis Valley until the British-ordered expulsion of Acadians in 1755 which is memorialized at Grand-Pré in the eastern part of the valley. New England Planters moved in to occupy the abandoned Acadian farming areas and the region also saw subsequent settlement by Loyalist refugees of the American Revolutionary War, as well as foreign Protestants. These were followed by significant numbers of freed Africans in the War of 1812, Irish immigrants in the mid-19th century and Dutch immigrants after World War II. Agriculture in the Annapolis valley boomed in the late 19th century with the arrival of the Windsor and Annapolis Railway, later the Dominion Atlantic Railway, which developed large export markets for Annapolis Valley apples.
The Annapolis Valley Regional Library was established in 1949. It was the first regional library system in Nova Scotia.
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# Annapolis Valley
## Economy
The Valley has traditionally been built on a diversified agricultural industry, with a wide range of output ranging from livestock to fruit trees and berries. The last quarter-century has also seen the development of a wine industry, with such notable wineries as Gaspereau Vineyards winning national and international awards for their produce.
Today, the Valley is still largely dominated by agriculture but also has a growing diversity in its economies, partly aided by the importance of post-secondary education centres provided by Acadia University in Wolfville, and the Nova Scotia Community College campuses located in Kentville, Middleton, Lawrencetown, and Digby.
Michelin has an important truck tire manufacturing plant in Waterville and the Department of National Defence has its largest air force base in Atlantic Canada located at CFB Greenwood along with an important training facility at Camp Aldershot, near Kentville.
Tourism is also an important industry and the Annapolis Valley is known for its scenic farmland, although today some is threatened with suburban development in the eastern end, and a great deal has been abandoned. The valley also struggles with pollution from farm runoffs and residential sewers in its two major rivers, the Annapolis River and the Cornwallis River. The Annapolis Valley additionally has become home to the majority of Nova Scotia wineries, located in either the Gaspereau Valley or in the Canning, Grand Pré, or Bear River areas.
The Valley is home to the annual Apple Blossom Festival, held in late spring. In July is the annual Steer Bar-B-Que in Kingston, and Heart of the Valley Festival in Middleton. August sees Mud Creek Days in Wolfville and the Annapolis Valley Exhibition in Lawrencetown. Bridgetown\'s Cider Festival comes in mid-September. The Canadian Deep Roots Music Festival is held each year at the end of September in Wolfville, a community-based festival, supported by both the Town of Wolfville and Acadia University and built by over 100 volunteers, and on in-kind and financial support from virtually all sectors of the Valley community. Late October sees Wolfville and Kings County play host to Devour! The Food Film Fest, an annual international film festival celebrating all things culinary. Farmers markets in Annapolis Royal, Bridgetown, Middleton, Kentville, Kingsport, Berwick and Wolfville bring a produce and other goods to the public every week. In the fall, there is the Pumpkin People in Kentville
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# Apple II (original)
The **Apple II** (stylized as `{{nowrap|'''apple ]['''}}`{=mediawiki}) is a personal computer released by Apple Inc. in June 1977. It was one of the first successful mass-produced microcomputer products and is widely regarded as one of the most important personal computers of all time due to its role in popularizing home computing and influencing later software development.
The Apple II was designed primarily by Steve Wozniak. The system is based around the 8-bit MOS Technology 6502 microprocessor. Jerry Manock designed the foam-molded plastic case, Rod Holt developed the switching power supply, while Steve Jobs was not involved in the design of the computer. It was introduced by Jobs and Wozniak at the 1977 West Coast Computer Faire, and marks Apple\'s first launch of a computer aimed at a consumer market---branded toward American households rather than businessmen or computer hobbyists.
*Byte* magazine referred to the Apple II, Commodore PET 2001, and TRS-80 as the \"1977 Trinity\". As the Apple II had the defining feature of being able to display color graphics, the Apple logo was redesigned to have a spectrum of colors.
The Apple II was the first in a series of computers collectively referred to by the Apple II name. It was followed by the Apple II+, Apple IIe, Apple IIc, Apple IIc Plus, and the 16-bit Apple IIGS---all of which remained compatible. Production of the last available model, the Apple IIe, ceased in November 1993.
## History
By 1976, Steve Jobs had convinced product designer Jerry Manock (who had formerly worked at Hewlett Packard designing calculators) to create the \"shell\" for the Apple II---a smooth case inspired by kitchen appliances that concealed the internal mechanics. The earliest Apple II computers were assembled in Silicon Valley and later in Texas; printed circuit boards were manufactured in Ireland and Singapore. The first computers went on sale on June 10, 1977 with an MOS Technology 6502 microprocessor running at 1.023 MHz (`{{frac|2|7}}`{=mediawiki} of the NTSC color subcarrier), two game paddles (bundled until 1980, when they were found to violate FCC regulations), 4 KiB of RAM, an audio cassette interface for loading programs and storing data, and the Integer BASIC programming language built into ROMs. The video controller displayed 24 lines by 40 columns of monochrome, uppercase-only text on the screen (the original character set matches ASCII characters 20~h~ to 5F~h~), with NTSC composite video output suitable for display on a video monitor or on a regular TV set (by way of a separate RF modulator).
The original retail price of the computer with 4 KiB of RAM was `{{US$|1298|1977|round=-1}}`{=mediawiki} and with the maximum 48 KiB of RAM, it was `{{US$|2638|1977|round=-1}}`{=mediawiki} To reflect the computer\'s color graphics capability, the Apple logo on the casing has rainbow stripes, which remained a part of Apple\'s corporate logo until early 1998. Perhaps most significantly, the Apple II was a catalyst for personal computers across many industries; it opened the doors to software marketed at consumers.
Certain aspects of the system\'s design were influenced by Atari, Inc.\'s arcade video game *Breakout* (1976), which was designed by Wozniak, who said: \"A lot of features of the Apple II went in because I had designed *Breakout* for Atari. I had designed it in hardware. I wanted to write it in software now\". This included his design of color graphics circuitry, the addition of game paddle support and sound, and graphics commands in Integer BASIC, with which he wrote *Brick Out*, a software clone of his own hardware game. Wozniak said in 1984: \"Basically, all the game features were put in just so I could show off the game I was familiar with---*Breakout*---at the Homebrew Computer Club. It was the most satisfying day of my life \[when\] I demonstrated *Breakout*---totally written in BASIC. It seemed like a huge step to me. After designing hardware arcade games, I knew that being able to program them in BASIC was going to change the world.\"
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# Apple II (original)
## Overview
In the May 1977 issue of *Byte*, Steve Wozniak published a detailed description of his design; the article began, \"To me, a personal computer should be small, reliable, convenient to use, and inexpensive.\"
The Apple II used peculiar engineering shortcuts to save hardware and reduce costs, such as:
- Taking advantage of the way the 6502 processor accesses memory: it occurs only on alternate phases of the clock cycle; video generation circuitry memory access on the otherwise unused phase avoids memory contention issues and interruptions of the video stream;
- This arrangement simultaneously eliminated the need for a separate refresh circuit for DRAM chips, as video transfer accessed each row of dynamic memory within the timeout period. In addition, it did not require separate RAM chips for video RAM, while the PET and TRS-80 had SRAM chips for video;
- Apart from the 6502 CPU and a few support chips, the vast majority of the semiconductors used were 74LS low-power Schottky chips;
- Rather than use a complex analog-to-digital circuit to read the outputs of the game controller, Wozniak used a simple timer circuit, built around a quad 555 timer IC called a 558, whose period is proportional to the resistance of the game controller, and he used a software loop to measure the timers;
- A single 14.31818 MHz master oscillator (f~M~) was divided by various ratios to produce all other required frequencies, including microprocessor clock signals (f~M~/14), video transfer counters, and color-burst samples (f~M~/4). A solderable jumper on the main board allowed to switch between European 50 Hz and USA 60 Hz video.
The text and graphics screens have a complex arrangement. For instance, the scanlines were not stored in sequential areas of memory. This complexity was reportedly due to Wozniak\'s realization that the method would allow for the refresh of dynamic RAM as a side effect (as described above). This method had no cost overhead to have software calculate or look up the address of the required scanline and avoided the need for significant extra hardware. Similarly, in high-resolution graphics mode, color is determined by pixel position and thus can be implemented in software, saving Wozniak the chips needed to convert bit patterns to colors. This also allowed the ability to draw text with subpixel rendering, since orange and blue pixels appear half a pixel-width farther to the right on the screen than green and purple pixels.
The Apple II at first used data cassette storage, like most other microcomputers of the time. In 1978, the company introduced an external `{{frac|5|1|4}}`{=mediawiki}-inch floppy disk drive, called Disk II (stylized as Disk \]\[), attached through a controller card that plugs into one of the computer\'s expansion slots (usually slot 6). The Disk II interface, created by Wozniak, is regarded as an engineering masterpiece for its economy of electronic components.
The approach taken in the Disk II controller is typical of Wozniak\'s designs. With a few small-scale logic chips and a cheap PROM (programmable read-only memory), he created a functional floppy disk interface at a fraction of the component cost of standard circuit configurations.
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# Apple II (original)
## Case design {#case_design}
The first production Apple II computers had hand-molded cases; these had visible bubbles and other lumps in them from the imperfect plastic molding process, which was soon switched to machine molding. In addition, the initial case design had no vent openings, causing high heat buildup from the printed circuit board (PCB) and resulting in the plastic softening and sagging. Apple added vent holes to the case within three months of production; customers with the original case could have them replaced at no charge.
## PCB revisions {#pcb_revisions}
The Apple II\'s printed circuit board (PCB) underwent several revisions, as Steve Wozniak made modifications to it. The earliest version was known as Revision 0, and the first 6,000 units shipped used it. Later revisions added a \"color killer\" circuit to prevent color fringing when the computer was in text mode, as well as modifications to improve the reliability of cassette I/O. Revision 0 Apple IIs powered up in an undefined mode and had garbage on-screen, requiring the user to press Reset. This was eliminated in later board revisions. Revision 0 Apple IIs could display only four colors in hi-res mode, but Wozniak was able to increase this to six hi-res colors on later board revisions. (Technically it was eight, but only six were visible.)
Apple II PCBs have three RAM banks for a total of 24 RAM chips. Original Apple IIs had jumper switches to adjust RAM size, and RAM configurations could be 4, 8, 12, 16, 20, 24, 32, 36, or 48 KiB. The three smallest memory configurations used 4kx1 DRAMs, with larger ones using 16kx1 DRAMs, or mix of 4-kilobyte and 16-kilobyte banks (the chips in any one bank have to be the same size). The early Apple II+ models retained this feature, but after a drop in DRAM prices, Apple redesigned the circuit boards without the jumpers, so that only 16kx1 chips were supported. A few months later, they started shipping all machines with a full 48 KiB complement of DRAM.
Unlike most machines, all integrated circuits on the Apple II PCB were socketed; this cost more to manufacture and created the possibility of loose chips causing a system malfunction, but it was considered preferable to make servicing and replacement of bad chips easier.
The Apple II PCB lacks any means of generating an interrupt request, although expansion cards may generate one. Program code had to stop everything to perform any I/O task; like many of the computer\'s other idiosyncrasies, this was due to cost reasons and Steve Wozniak assuming interrupts were not needed for gaming or using the computer as a teaching tool.
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# Apple II (original)
## Display and graphics {#display_and_graphics}
Color on the Apple II series uses a quirk of the NTSC television signal standard, which made color display relatively easy and inexpensive to implement. The original NTSC television signal specification was black and white. Color was added later by adding a 3.58-megahertz subcarrier signal that was partially ignored by black-and-white TV sets. Color is encoded based on the phase of this signal in relation to a reference color burst signal. The result is that the position, size, and intensity of a series of pulses define color information. These pulses can translate into pixels on the computer screen, with the possibility of exploiting composite artifact colors.
The Apple II display provides two pixels per subcarrier cycle. When the color burst reference signal is turned on and the computer is attached to a color display, it can display green by showing one alternating pattern of pixels, magenta with an opposite pattern of alternating pixels, and white by placing two pixels next to each other. Blue and orange are available by tweaking the pixel offset by half a pixel-width in relation to the color-burst signal. The high-resolution display offers more colors by compressing more (and narrower) pixels into each subcarrier cycle.
The coarse, low-resolution graphics display mode works differently, as it can output a pattern of dots per pixel to offer more color options. These patterns are stored in the character generator ROM, and replace the text character bit patterns when the computer is switched to low-res graphics mode. The text mode and low-res graphics mode use the same memory region and the same circuitry is used for both.
A single HGR page occupied 8 KiB of RAM; in practice this meant that the user had to have at least 12 KiB of total RAM to use HGR mode and 20 KiB to use two pages. Early Apple II games from the 1977--79 period often ran only in text or low-resolution mode in order to support users with small memory configurations; HGR not being near universally supported by games until 1980.
## Sound
Rather than a dedicated sound-synthesis chip, the Apple II contains a toggle circuit that can only emit a click through a built-in speaker or a line-out jack. More complex sounds, such as music or audio samples, are generated by software manually toggling the speaker at an appropriate frequency. This technique requires careful and precise timing, rendering it difficult to display moving graphics while sound is playing. Third party expansion cards were later released that addressed this problem.
A similar technique is used for cassette storage: cassette output works the same as the speaker, and input uses a simple zero-crossing detector as a 1-bit audio digitizer. Routines in machine ROM encode and decode data in frequency-shift keying for the cassette.
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# Apple II (original)
## Programming languages {#programming_languages}
Initially, the Apple II was shipped with Integer BASIC encoded in the motherboard ROM chips. Written by Wozniak, the interpreter enabled users to write software applications without needing to purchase additional development utilities. Written with game programmers and hobbyists in mind, the language only supported the encoding of numbers in 16-bit integer format. Since it only supported integers between -32768 and +32767 (signed 16-bit integer), it was less suitable to business software, and Apple soon received complaints from customers. Because Steve Wozniak was busy developing the Disk II hardware, he did not have time to modify Integer BASIC for floating point support. Apple instead licensed Microsoft\'s 6502 BASIC to create Applesoft BASIC.
Disk users normally purchased a so-called Language Card, which had Applesoft in ROM, and was located below the Integer BASIC ROM in system memory. The user could switch between either BASIC by typing `{{code|FP}}`{=mediawiki} or `{{code|INT}}`{=mediawiki} in BASIC prompt. Apple also offered a different version of Applesoft for cassette users, which occupied low memory, and was started by using the `{{code|LOAD}}`{=mediawiki} command in Integer BASIC.
As shipped, Apple II incorporated a machine code monitor with commands for displaying and altering the computer\'s RAM, either one byte at a time, or in blocks of 256 bytes at once. This enabled programmers to write and debug machine code programs without further development software. The computer powers on into the monitor ROM, displaying a `{{code|*}}`{=mediawiki} prompt. From there, `{{key press|Ctrl|B}}`{=mediawiki} enters BASIC, or a machine language program can be loaded from cassette. Disk software can be booted with `{{key press|Ctrl|P}}`{=mediawiki} followed by `{{key press|6}}`{=mediawiki}, referring to Slot 6 which normally contained the Disk II controller.
A 6502 assembler was soon offered on disk, and later the UCSD compiler and operating system for the Pascal language were made available. The Pascal system requires a 16 KiB RAM card to be installed in the language card position (expansion slot 0) in addition to the full 48 KiB of motherboard memory.
## Manual
The first 1,000 or so Apple IIs shipped in 1977 with a 68-page mimeographed \"Apple II Mini Manual\", hand-bound with brass paper fasteners. This was the basis for the *Apple II Reference Manual,* which became known as the Red Book for its red cover, published in January 1978. All existing customers who sent in their warranty cards were sent free copies of the Red Book. The *Apple II Reference Manual* contained the complete schematic of the entire computer\'s circuitry, and a complete source listing of the \"Monitor\" ROM firmware that served as the machine\'s BIOS.
An Apple II manual signed by Steve Jobs in 1980 with the inscription \"Julian, your generation is the first to grow up with computers. Go change the world.\" sold at auction for \$787,484 in 2021.
## Operating system {#operating_system}
The original Apple II came with an 8 KiB ROM containing a BASIC variant called Integer BASIC as well as a resident monitor called the Apple System Monitor. Initially, only cassette tape was available for storage, which was considered too slow and unreliable for business use. In late 1977, Apple began to develop the Disk II floppy disk drive and required an operating system to utilize it. The existing standard at the time was CP/M, but due to incompatibility with the 6502 processor and a perceived clunkiness, Apple contracted Shepardson Microsystems for \$13,000 to write Apple DOS. At Shepardson, Paul Laughton developed the software in just 35 days, a remarkably short deadline, even for the time. The Disk II and Apple DOS were released in late 1978. The final and most popular version of this software was Apple DOS 3.3.
Apple DOS was superseded by ProDOS, which supported a hierarchical filesystem and larger storage devices. With an optional third-party Z80-based expansion card, the Apple II could boot into the CP/M operating system and run WordStar, dBase II, and other CP/M software.
Apple released Applesoft BASIC in 1977, a more advanced variant of the language which users could run instead of Integer BASIC for more capabilities, such as the ability to use floating point numbers.
Some commercial Apple II software came on self-booting disks and did not use standard DOS disk formats. This discouraged the copying or modifying of the software on the disks, and improved loading speed.
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# Apple II (original)
## Third-party devices and applications {#third_party_devices_and_applications}
When the Apple II initially shipped in June 1977, no expansion cards were available for the slots. This meant that the user did not have any way of connecting a modem or a printer. One popular hack involved connecting a teletype machine to the cassette output.
Wozniak\'s open-architecture design and Apple II\'s multiple expansion slots permitted a wide variety of third-party devices, including peripheral cards, such as serial controllers, display controllers, memory boards, hard disks, networking components, and real-time clocks. There were plug-in expansion cards---such as the Z-80 SoftCard---that permitted Apple II to use the Z80 processor and run programs for the CP/M operating system, including the dBase II database and the WordStar word processor. The Z80 card also allowed the connection to a modem, and thereby to any networks that a user might have access to. In the early days, such networks were scarce. But they expanded significantly with the development of bulletin board systems in later years. There was also a third-party 6809 card that allowed OS-9 Level One to be run. Third-party sound cards greatly improved audio capabilities, allowing simple music synthesis and text-to-speech functions. Apple II accelerator cards doubled or quadrupled the computer\'s speed.
Early Apple IIs were often sold with a Sup\'R\'Mod, which allowed the composite video signal to be viewed in a television.
The Soviet Union radio-electronics industry designed Apple II-compatible computer Agat. Roughly 12,000 Agat 7 and 9 models were produced and they were widely used in Soviet schools. Agat 9 computers could run \"Apple II\" compatibility and native modes. \"Apple II\" mode allowed to run a wider variety of (presumably pirated) Apple II software, but at the expense of less RAM. Because of that Soviet developers preferred native mode over \"Apple II\" compatibility mode.
In 1978, Bob Bishop of Apple Computer, Inc. programmed 9 Apple II computers to run the gameboard on the TV game show *Tic-Tac-Dough*;. Each Apple was responsible for displaying various contents for each box of the gameboard (category, X, O, bonus game numbers and amounts, TIC, TAC or Dragon, as well displaying custom messages and an active screensaver), and in turn controlled by an Altair 8800 system. It was the first game show to use computerized graphics.
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# Apple II (original)
## Reception
Jesse Adams Stein wrote, \"As the first company to release a \'consumer appliance\' micro-computer, Apple Computer offers us a clear view of this shift from a *machine* to an *appliance*.\" But the company also had \"to negotiate the attitudes of its potential buyers, bearing in mind social anxieties about the uptake of new technologies in multiple contexts. The office, the home and the \'office-in-the-home\' were implicated in these changing spheres of gender stereotypes and technological development.\" After seeing a crude, wire-wrapped prototype demonstrated by Wozniak and Steve Jobs in November 1976, *Byte* predicted in April 1977, that the Apple II \"may be the first product to fully qualify as the \'appliance computer\' \... a completed system which is purchased off the retail shelf, taken home, plugged in and used\". The computer\'s color graphics capability especially impressed the magazine. The magazine published a favorable review of the computer in March 1978, concluding: \"For the user that wants color graphics, the Apple II is the only practical choice available in the \'appliance\' computer class.\"
*Personal Computer World* in August 1978 also cited the color capability as a strength, stating that \"the prime reason that anyone buys an Apple II must surely be for the colour graphics\". While mentioning the \"oddity\" of the artifact colors that produced output \"that is not always what one wishes to do\", it noted that \"no-one has colour graphics like this at this sort of price\". The magazine praised the sophisticated monitor software, user expandability, and comprehensive documentation. The author concluded that \"the Apple II is a very promising machine\" which \"would be even more of a temptation were its price slightly lower \... for the moment, colour is an Apple II\".
Although it sold well from the launch, the initial market was to hobbyists and computer enthusiasts. Sales expanded exponentially into the business and professional market, when the spreadsheet program VisiCalc was launched in mid-1979. VisiCalc is credited as the defining killer app in the microcomputer industry.
By the end of 1977 Apple had sales of `{{US$|long=no|775,000}}`{=mediawiki} for the fiscal year, which included sales of the Apple I. This put Apple clearly behind the others of the \"holy trinity\" of the TRS-80 and Commodore PET, even though the TRS-80 was launched last of the three. However, during the first five years of operations, revenues doubled about every four months. Between September 1977 and September 1980, annual sales grew from `{{US$|long=no|775,000}}`{=mediawiki} to `{{US$|long=no|118 million}}`{=mediawiki}. During this period the sole products of the company were the Apple II and its peripherals, accessories, and software.
In 2006, PC World wrote that the Apple II was the greatest PC of all time
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# Alexis Korner
**Alexis Andrew Nicholas Koerner** (19 April 1928 -- 1 January 1984), known professionally as **Alexis Korner**, was a British blues musician and radio broadcaster, who has sometimes been referred to as \"a founding father of British blues\". A major influence on the sound of the British music scene in the 1960s, he was instrumental in the formation of several notable British bands including The Rolling Stones and Free. Korner was inducted into the Rock and Roll Hall of Fame in the musical influence category in 2024.
## Early career {#early_career}
Alexis Andrew Nicholas Koerner was born on 19 April 1928 in Paris, France, to an Austrian Jewish father and a mother of Greek, Turkish and Austrian descent. He spent his childhood in France, Switzerland and North Africa, and arrived in London in 1940 after the start of the Second World War. One memory of his youth was listening to a record by black pianist Jimmy Yancey during a German air raid. Korner said, \"From then on all I wanted to do was play the blues.\"
After the war, Korner played piano and guitar (his first guitar was built by friend and author Sydney Hopkins, who wrote *Mister God, This Is Anna*) and in 1949 joined Chris Barber\'s Jazz Band where he met blues harmonica player Cyril Davies. They started playing together as a duo, started the influential London Blues and Barrelhouse Club in 1955 and made their first record together in 1957.
Korner made his first official record on Decca Records DFE 6286 in the company of Ken Colyer\'s Skiffle Group. His talent extended to playing mandolin on one of the tracks of this British EP, recorded in London on 28 July 1955. Korner encouraged many American blues artists, previously virtually unknown in Britain, to perform at the London Blues and Barrelhouse Club, which he established with Davies at the Round House pub in Soho.
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# Alexis Korner
## The 1960s {#the_1960s}
In 1961, Korner and Davies formed Blues Incorporated, initially a loose-knit group of musicians with a shared love of electric blues and R&B music. The group included, at various times, Charlie Watts, Jack Bruce, Ginger Baker, Long John Baldry, Graham Bond, Danny Thompson and Dick Heckstall-Smith. It also attracted a wider crowd of mostly younger fans, some of whom occasionally performed with the group, including Mick Jagger, Keith Richards, Brian Jones, Geoff Bradford, Rod Stewart, John Mayall, and Jimmy Page.
Although Cyril Davies left the group in late 1962, Blues Incorporated continued to record, with Korner at the helm, until 1966. However, by that time its originally stellar line-up (and crowd of followers) had mostly left to start their own bands. While his one-time acolytes, the Rolling Stones and Cream, made the front pages of music magazines all over the world, Korner was relegated to the role of \'elder statesman\'.
In 1966, Korner formed the trio Free At Last with Hughie Flint and Binky McKenzie. Flint later recalled \"I played with Alexis, right after leaving The Bluesbreakers, in a trio, which Alexis named *Free At Last*, a sort of mini and slightly restricted version of Blues Incorporated. Playing with Alexis was very loose. We would play anything from Percy Mayfield\'s 'River\'s Invitation\' to Charles Mingus\' 'Better Get It In Your Soul\' -- with lots of freaky guitar and bass solos. Alexis, like John Mayall had the most eclectic taste in music, very knowledgeable, and generous, and I am indebted to both of them for my wide approach to music\".
Although *Free At Last* was short-lived, Korner ensured its name lived on in part by christening another young group of aspiring musicians, Free. Korner was instrumental in the formation of the band in April 1968, and continued to mentor them until they secured a deal with Island Records.
Although he himself was a blues purist, Korner criticised better-known British blues musicians during the blues boom of the late 1960s for their blind adherence to Chicago blues, as if the music came in no other form. He liked to surround himself with jazz musicians and often performed with a horn section drawn from a pool that included, among others, saxophone players Art Themen, Mel Collins, Dick Heckstall-Smith, and Lol Coxhill.
While touring Scandinavia he formed the band New Church with guitarist and singer Peter Thorup. They subsequently were one of the support bands at the Rolling Stones Free Concert in Hyde Park, London, on 5 July 1969. Jimmy Page reportedly found out about a new singer, Robert Plant, who had been jamming with Korner, who wondered why Plant had not yet been discovered. Plant and Korner were recording an album with Plant on vocals until Page had asked him to join \"the New Yardbirds\", a.k.a. Led Zeppelin. Only two songs are in circulation from these recordings: \"Steal Away\" and \"Operator\". Korner gave one of his last radio interviews to BBC Midlands on the *Record Collectors Show* with Mike Adams and Chris Savory.
## Broadcasting
In the 1960s Korner began a media career, working initially as a showbusiness interviewer and then on ITV\'s *Five O\'Clock Club*, a children\'s TV show. Korner also wrote about blues for the music papers, and continued to maintain his own career as a blues artist, especially in Europe. Korner\'s main career in the 1970s was in broadcasting. In 1973, he presented a six-part documentary on BBC Radio 1, *The Rolling Stones Story*, and in 1977 he established a Sunday-night show on Radio 1, *Alexis Korner\'s Blues and Soul Show*, which ran until 1981. He also used his gravelly voice to great effect as an advertising voice-over artist. In 1983, Korner presented the 13 part BBC Radio 1 series, Guitar Greats, interviewing each of the artists, and playing their music.
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# Alexis Korner
## 1970s
### CCS period {#ccs_period}
In 1970, Korner and Thorup formed a big-band ensemble, CCS -- short for \"The Collective Consciousness Society\" -- which had several hit singles produced by Mickie Most, including a version of Led Zeppelin\'s \"Whole Lotta Love\", which was used as the theme for BBC\'s *Top of the Pops* between 1970 and 1981. Another instrumental called \"Brother\" was used as the theme to the BBC Radio 1 Top 20/40 when Tom Browne/Simon Bates presented the programme in the 1970s. It was also used in the 1990s on Radio Luxembourg for the Top 20 Singles chart. This was the period of Korner\'s greatest commercial success in the UK. In 1973, he provided a voice part for the Hot Chocolate single release Brother Louie.
### 1970s to 1984 {#s_to_1984}
In 1973, he and Peter Thorup formed another group, Snape, with Boz Burrell, Mel Collins, and Ian Wallace, who were previously together in King Crimson. Korner also played on B.B. King\'s *In London* album, and cut his own, similar \"supersession\" album; *Get Off My Cloud*, with Keith Richards, Steve Marriott, Peter Frampton, Nicky Hopkins and members of Joe Cocker\'s Grease Band. In the mid-1970s, while touring Germany, Korner established an intensive working relationship with bassist Colin Hodgkinson who played for the support act Back Door. They would continue to collaborate right up until Korner\'s death.
In 1978, for Korner\'s 50th birthday, an all-star concert was held featuring many of his above-mentioned friends, as well as Eric Clapton, Paul Jones, Chris Farlowe, Zoot Money and others, which was later released as *The Party Album*, and as a video.
In 1981, Korner joined another \"supergroup\", Rocket 88, a project led by Ian Stewart based on boogie-woogie keyboard players, which featured a rhythm section comprising Jack Bruce and Charlie Watts, among others, as well as a horn section. They toured Europe and released an album on Atlantic Records. He played in Italy with Paul Jones and the Blues Society of Italian bluesman Guido Toffoletti.
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# Alexis Korner
## Family life and death {#family_life_and_death}
In 1950, Korner married Roberta Melville (died 2021), daughter of art critic Robert Melville. He had a daughter, singer Sappho Gillett Korner (died 2006), and two sons, guitarist Nicholas \'Nico\' Korner (died 1989) and sound engineer Damian Korner (died 2008).
Alexis Korner died in London from lung cancer on 1 January 1984, at the age of 55.
Korner was posthumously inducted, by Keith Richards, into the Rock and Roll Hall of Fame in 2024 in the musical influence category
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# Adrenal gland
The **adrenal glands** (also known as **suprarenal glands**) are endocrine glands that produce a variety of hormones including adrenaline and the steroids aldosterone and cortisol. They are found above the kidneys. Each gland has an outer cortex which produces steroid hormones and an inner medulla. The adrenal cortex itself is divided into three main zones: the zona glomerulosa, the zona fasciculata and the zona reticularis.
The adrenal cortex produces three main types of steroid hormones: mineralocorticoids, glucocorticoids, and androgens. Mineralocorticoids (such as aldosterone) produced in the zona glomerulosa help in the regulation of blood pressure and electrolyte balance. The glucocorticoids cortisol and cortisone are synthesized in the zona fasciculata; their functions include the regulation of metabolism and immune system suppression. The innermost layer of the cortex, the zona reticularis, produces androgens that are converted to fully functional sex hormones in the gonads and other target organs. The production of steroid hormones is called steroidogenesis, and involves a number of reactions and processes that take place in cortical cells. The medulla produces the catecholamines, which function to produce a rapid response throughout the body in stress situations.
A number of endocrine diseases involve dysfunctions of the adrenal gland. Overproduction of cortisol leads to Cushing\'s syndrome, whereas insufficient production is associated with Addison\'s disease. Congenital adrenal hyperplasia is a genetic disease produced by dysregulation of endocrine control mechanisms. A variety of tumors can arise from adrenal tissue and are commonly found in medical imaging when searching for other diseases. `{{TOC limit|3}}`{=mediawiki}
## Structure
The adrenal glands are located on both sides of the body in the retroperitoneum, above and slightly medial to the kidneys. In humans, the right adrenal gland is pyramidal in shape, whereas the left is semilunar or crescent shaped and somewhat larger. The adrenal glands measure approximately 5 cm in length, 3 cm in width, and up to 1 cm in thickness. Their combined weight in an adult human ranges from 7 to 10 grams. The glands are yellowish in colour.
The adrenal glands are surrounded by a fatty capsule and lie within the renal fascia, which also surrounds the kidneys. A weak septum (wall) of connective tissue separates the glands from the kidneys. The adrenal glands are directly below the diaphragm, and are attached to the crura of the diaphragm by the renal fascia.
Each adrenal gland has two distinct parts, each with a unique function, the outer adrenal cortex and the inner medulla, both of which produce hormones.
### Adrenal cortex {#adrenal_cortex}
The adrenal cortex is the outer region and also the largest part of an adrenal gland. It is divided into three separate zones: zona glomerulosa, zona fasciculata and zona reticularis. Each zone is responsible for producing specific hormones. The adrenal cortex is the outermost layer of the adrenal gland. Within the cortex are three layers, called \"zones\". When viewed under a microscope each layer has a distinct appearance, and each has a different function. The adrenal cortex is devoted to production of hormones, namely aldosterone, cortisol, and androgens.
#### Zona glomerulosa {#zona_glomerulosa}
The outermost zone of the adrenal cortex is the zona glomerulosa. It lies immediately under the fibrous capsule of the gland. Cells in this layer form oval groups, separated by thin strands of connective tissue from the fibrous capsule of the gland and carry wide capillaries.
This layer is the main site for production of aldosterone, a mineralocorticoid, by the action of the enzyme aldosterone synthase. Aldosterone plays an important role in the long-term regulation of blood pressure.
#### Zona fasciculata {#zona_fasciculata}
The zona fasciculata is situated between the zona glomerulosa and zona reticularis. Cells in this layer are responsible for producing glucocorticoids such as cortisol. It is the largest of the three layers, accounting for nearly 80% of the volume of the cortex. In the zona fasciculata, cells are arranged in columns radially oriented towards the medulla. Cells contain numerous lipid droplets, abundant mitochondria and a complex smooth endoplasmic reticulum.
#### Zona reticularis {#zona_reticularis}
The innermost cortical layer, the zona reticularis, lies directly adjacent to the medulla. It produces androgens, mainly dehydroepiandrosterone (DHEA), DHEA sulfate (DHEA-S), and androstenedione (the precursor to testosterone) in humans. Its small cells form irregular cords and clusters, separated by capillaries and connective tissue. The cells contain relatively small quantities of cytoplasm and lipid droplets, and sometimes display brown lipofuscin pigment.
### Medulla
The adrenal medulla is at the center of each adrenal gland, and is surrounded by the adrenal cortex. The chromaffin cells of the medulla are the body\'s main source of the catecholamines, such as adrenaline and noradrenaline, released by the medulla. Approximately 20% noradrenaline (norepinephrine) and 80% adrenaline (epinephrine) are secreted here.
The adrenal medulla is driven by the sympathetic nervous system via preganglionic fibers originating in the thoracic spinal cord, from vertebrae T5--T11. Because it is innervated by preganglionic nerve fibers, the adrenal medulla can be considered as a specialized sympathetic ganglion. Unlike other sympathetic ganglia, however, the adrenal medulla lacks distinct synapses and releases its secretions directly into the blood.
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# Adrenal gland
## Structure
### Blood supply {#blood_supply}
The adrenal glands have one of the greatest blood supply rates per gram of tissue of any organ: up to 60 small arteries may enter each gland. Three arteries usually supply each adrenal gland:
- The superior suprarenal artery, a branch of the inferior phrenic artery
- The middle suprarenal artery, a direct branch of the abdominal aorta
- The inferior suprarenal artery, a branch of the renal artery
These blood vessels supply a network of small arteries within the capsule of the adrenal glands. Thin strands of the capsule enter the glands, carrying blood to them.
Venous blood is drained from the glands by the suprarenal veins, usually one for each gland:
- The right suprarenal vein drains into the inferior vena cava.
- The left suprarenal vein drains into the left renal vein or the left inferior phrenic vein.
The central adrenomedullary vein, in the adrenal medulla, is an unusual type of blood vessel. Its structure is different from the other veins in that the smooth muscle in its tunica media (the middle layer of the vessel) is arranged in conspicuous, longitudinally oriented bundles.
### Variability
The adrenal glands may not develop at all, or may be fused in the midline behind the aorta. These are associated with other congenital abnormalities, such as failure of the kidneys to develop, or fused kidneys. The gland may develop with a partial or complete absence of the cortex, or may develop in an unusual location.
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# Adrenal gland
## Function
The adrenal gland secretes a number of different hormones which are metabolised by enzymes either within the gland or in other parts of the body. These hormones are involved in a number of essential biological functions.
### Corticosteroids
Corticosteroids are a group of steroid hormones produced from the cortex of the adrenal gland, from which they are named.
- Mineralocorticoids such as aldosterone regulate salt (\"mineral\") balance and blood pressure
- Glucocorticoids such as cortisol influence metabolism rates of proteins, fats and sugars (\"glucose\").
- Androgens such as dehydroepiandrosterone.
Mineralocorticoids
The adrenal gland produces aldosterone, a mineralocorticoid, which is important in the regulation of salt (\"mineral\") balance and blood volume. In the kidneys, aldosterone acts on the distal convoluted tubules and the collecting ducts by increasing the reabsorption of sodium and the excretion of both potassium and hydrogen ions. Aldosterone is responsible for the reabsorption of about 2% of filtered glomerular filtrate. Sodium retention is also a response of the distal colon and sweat glands to aldosterone receptor stimulation. Angiotensin II and extracellular potassium are the two main regulators of aldosterone production. The amount of sodium present in the body affects the extracellular volume, which in turn influences blood pressure. Therefore, the effects of aldosterone in sodium retention are important for the regulation of blood pressure.
Glucocorticoids
Cortisol is the main glucocorticoid in humans. In species that do not create cortisol, this role is played by corticosterone instead. Glucocorticoids have many effects on metabolism. As their name suggests, they increase the circulating level of glucose. This is the result of an increase in the mobilization of amino acids from protein and the stimulation of synthesis of glucose from these amino acids in the liver. In addition, they increase the levels of free fatty acids, which cells can use as an alternative to glucose to obtain energy. Glucocorticoids also have effects unrelated to the regulation of blood sugar levels, including the suppression of the immune system and a potent anti-inflammatory effect. Cortisol reduces the capacity of osteoblasts to produce new bone tissue and decreases the absorption of calcium in the gastrointestinal tract.
The adrenal gland secretes a basal level of cortisol but can also produce bursts of the hormone in response to adrenocorticotropic hormone (ACTH) from the anterior pituitary. Cortisol is not evenly released during the day -- its concentrations in the blood are highest in the early morning and lowest in the evening as a result of the circadian rhythm of ACTH secretion. Cortisone is an inactive product of the action of the enzyme 11β-HSD on cortisol. The reaction catalyzed by 11β-HSD is reversible, which means that it can turn administered cortisone into cortisol, the biologically active hormone.
Formation
All corticosteroid hormones share cholesterol as a common precursor. Therefore, the first step in steroidogenesis is cholesterol uptake or synthesis. Cells that produce steroid hormones can acquire cholesterol through two paths. The main source is through dietary cholesterol transported via the blood as cholesterol esters within low density lipoproteins (LDL). LDL enters the cells through receptor-mediated endocytosis. The other source of cholesterol is synthesis in the cell\'s endoplasmic reticulum. Synthesis can compensate when LDL levels are abnormally low. In the lysosome, cholesterol esters are converted to free cholesterol, which is then used for steroidogenesis or stored in the cell.
The initial part of conversion of cholesterol into steroid hormones involves a number of enzymes of the cytochrome P450 family that are located in the inner membrane of mitochondria. Transport of cholesterol from the outer to the inner membrane is facilitated by steroidogenic acute regulatory protein and is the rate-limiting step of steroid synthesis.
The layers of the adrenal gland differ by function, with each layer having distinct enzymes that produce different hormones from a common precursor. The first enzymatic step in the production of all steroid hormones is cleavage of the cholesterol side chain, a reaction that forms pregnenolone as a product and is catalyzed by the enzyme P450scc, also known as *cholesterol desmolase*. After the production of pregnenolone, specific enzymes of each cortical layer further modify it. Enzymes involved in this process include both mitochondrial and microsomal P450s and hydroxysteroid dehydrogenases. Usually a number of intermediate steps in which pregnenolone is modified several times are required to form the functional hormones. Enzymes that catalyze reactions in these metabolic pathways are involved in a number of endocrine diseases. For example, the most common form of congenital adrenal hyperplasia develops as a result of deficiency of 21-hydroxylase, an enzyme involved in an intermediate step of cortisol production.
Regulation
Glucocorticoids are under the regulatory influence of the hypothalamic--pituitary--adrenal axis (HPA) axis. Glucocorticoid synthesis is stimulated by adrenocorticotropic hormone (ACTH), a hormone released into the bloodstream by the anterior pituitary. In turn, production of ACTH is stimulated by the presence of corticotropin-releasing hormone (CRH), which is released by neurons of the hypothalamus. ACTH acts on the adrenal cells first by increasing the levels of StAR within the cells, and then of all steroidogenic P450 enzymes. The HPA axis is an example of a negative feedback system, in which cortisol itself acts as a direct inhibitor of both CRH and ACTH synthesis. The HPA axis also interacts with the immune system through increased secretion of ACTH at the presence of certain molecules of the inflammatory response.
Mineralocorticoid secretion is regulated mainly by the renin--angiotensin--aldosterone system (RAAS), the concentration of potassium, and to a lesser extent the concentration of ACTH. Sensors of blood pressure in the juxtaglomerular apparatus of the kidneys release the enzyme renin into the blood, which starts a cascade of reactions that lead to formation of angiotensin II. Angiotensin receptors in cells of the zona glomerulosa recognize the substance, and upon binding they stimulate the release of aldosterone.
### Androgens
Cells in zona reticularis of the adrenal glands produce male sex hormones, or androgens, the most important of which is DHEA. In general, these hormones do not have an overall effect in the male body, and are converted to more potent androgens such as testosterone and DHT or to estrogens (female sex hormones) in the gonads, acting in this way as a metabolic intermediate.
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# Adrenal gland
## Function
### Catecholamines
Also called epinephrine and norepinephrine, adrenaline and noradrenaline, respectively, are catecholamines -- water-soluble compounds that have a structure made of a catechol group and an amine group. The adrenal glands are responsible for most of the adrenaline that circulates in the body, but only for a small amount of circulating noradrenaline. These hormones are released by the adrenal medulla, which contains a dense network of blood vessels. Adrenaline and noradrenaline act by binding to adrenoreceptors throughout the body, with effects that include an increase in blood pressure and heart rate. Actions of adrenaline and noradrenaline are responsible for the fight or flight response, characterised by a quickening of breathing and heart rate, an increase in blood pressure, and constriction of blood vessels in many parts of the body.
#### Formation
Catecholamines are produced in chromaffin cells in the medulla of the adrenal gland, from tyrosine, a non-essential amino acid derived from food or produced from phenylalanine in the liver. The enzyme tyrosine hydroxylase converts tyrosine to L-DOPA in the first step of catecholamine synthesis. L-DOPA is then converted to dopamine before it can be turned into noradrenaline. In the cytosol, noradrenaline is converted to epinephrine by the enzyme phenylethanolamine N-methyltransferase (PNMT) and stored in granules. Glucocorticoids produced in the adrenal cortex stimulate the synthesis of catecholamines by increasing the levels of tyrosine hydroxylase and PNMT.
Catecholamine release is stimulated by the activation of the sympathetic nervous system. Splanchnic nerves of the sympathetic nervous system innervate the medulla of the adrenal gland. When activated, it evokes the release of catecholamines from the storage granules by stimulating the opening of calcium channels in the cell membrane.
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# Adrenal gland
## Gene and protein expression {#gene_and_protein_expression}
The human genome includes approximately 20,000 protein coding genes and 70% of these genes are expressed in the normal adult adrenal glands. Only some 250 genes are more specifically expressed in the adrenal glands compared to other organs and tissues. The adrenal-gland-specific genes with the highest level of expression include members of the cytochrome P450 superfamily of enzymes. Corresponding proteins are expressed in the different compartments of the adrenal gland, such as CYP11A1, HSD3B2 and FDX1 involved in steroid hormone synthesis and expressed in cortical cell layers, and PNMT and DBH involved in noradrenaline and adrenaline synthesis and expressed in the medulla.
## Development
The adrenal glands are composed of two heterogenous types of tissue. In the center is the adrenal medulla, which produces adrenaline and noradrenaline and releases them into the bloodstream, as part of the sympathetic nervous system. Surrounding the medulla is the cortex, which produces a variety of steroid hormones. These tissues come from different embryological precursors and have distinct prenatal development paths. The cortex of the adrenal gland is derived from mesoderm, whereas the medulla is derived from the neural crest, which is of ectodermal origin.
The adrenal glands in a newborn baby are much larger as a proportion of the body size than in an adult. For example, at age three months the glands are four times the size of the kidneys. The size of the glands decreases relatively after birth, mainly because of shrinkage of the cortex. The cortex, which almost completely disappears by age 1, develops again from age 4--5. The glands weigh about `{{Value|1|u=gram}}`{=mediawiki} at birth and develop to an adult weight of about `{{Value|4|u=grams}}`{=mediawiki} each. In a fetus the glands are first detectable after the sixth week of development.
### Cortex
Adrenal cortex tissue is derived from the intermediate mesoderm. It first appears 33 days after fertilisation, shows steroid hormone production capabilities by the eighth week and undergoes rapid growth during the first trimester of pregnancy. The fetal adrenal cortex is different from its adult counterpart, as it is composed of two distinct zones: the inner \"fetal\" zone, which carries most of the hormone-producing activity, and the outer \"definitive\" zone, which is in a proliferative phase. The fetal zone produces large amounts of adrenal androgens (male sex hormones) that are used by the placenta for estrogen biosynthesis. Cortical development of the adrenal gland is regulated mostly by ACTH, a hormone produced by the pituitary gland that stimulates cortisol synthesis. During midgestation, the fetal zone occupies most of the cortical volume and produces 100--200 mg/day of DHEA-S, an androgen and precursor of both androgens and estrogens (female sex hormones). Adrenal hormones, especially glucocorticoids such as cortisol, are essential for prenatal development of organs, particularly for the maturation of the lungs. The adrenal gland decreases in size after birth because of the rapid disappearance of the fetal zone, with a corresponding decrease in androgen secretion.
#### Adrenarche
During early childhood androgen synthesis and secretion remain low, but several years before puberty (from 6--8 years of age) changes occur in both anatomical and functional aspects of cortical androgen production that lead to increased secretion of the steroids DHEA and DHEA-S. These changes are part of a process called adrenarche, which has only been described in humans and some other primates. Adrenarche is independent of ACTH or gonadotropins and correlates with a progressive thickening of the zona reticularis layer of the cortex. Functionally, adrenarche provides a source of androgens for the development of axillary and pubic hair before the beginning of puberty.
### Medulla {#medulla_1}
The adrenal medulla is derived from neural crest cells, which come from the ectoderm layer of the embryo. These cells migrate from their initial position and aggregate in the vicinity of the dorsal aorta, a primitive blood vessel, which activates the differentiation of these cells through the release of proteins known as BMPs. These cells then undergo a second migration from the dorsal aorta to form the adrenal medulla and other organs of the sympathetic nervous system. Cells of the adrenal medulla are called chromaffin cells because they contain granules that stain with chromium salts, a characteristic not present in all sympathetic organs. Glucocorticoids produced in the adrenal cortex were once thought to be responsible for the differentiation of chromaffin cells. More recent research suggests that BMP-4 secreted in adrenal tissue is the main responsible for this, and that glucocorticoids only play a role in the subsequent development of the cells.
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# Adrenal gland
## Clinical significance {#clinical_significance}
The normal function of the adrenal gland may be impaired by conditions such as infections, tumors, genetic disorders and autoimmune diseases, or as a side effect of medical therapy. These disorders affect the gland either directly (as with infections or autoimmune diseases) or as a result of the dysregulation of hormone production (as in some types of Cushing\'s syndrome) leading to an excess or insufficiency of adrenal hormones and the related symptoms.
### Corticosteroid overproduction {#corticosteroid_overproduction}
#### Cushing\'s syndrome {#cushings_syndrome}
Cushing\'s syndrome is the manifestation of glucocorticoid excess. It can be the result of a prolonged treatment with glucocorticoids or be caused by an underlying disease which produces alterations in the HPA axis or the production of cortisol. Causes can be further classified into ACTH-dependent or ACTH-independent. The most common cause of endogenous Cushing\'s syndrome is a pituitary adenoma which causes an excessive production of ACTH. The disease produces a wide variety of signs and symptoms which include obesity, diabetes, increased blood pressure, excessive body hair (hirsutism), osteoporosis, depression, and most distinctively, stretch marks in the skin, caused by its progressive thinning.
#### Primary aldosteronism {#primary_aldosteronism}
When the zona glomerulosa produces excess aldosterone, the result is primary aldosteronism. Causes for this condition are bilateral hyperplasia (excessive tissue growth) of the glands, or aldosterone-producing adenomas (a condition called Conn\'s syndrome). Primary aldosteronism produces hypertension and electrolyte imbalance, increasing potassium depletion sodium retention.
### Adrenal insufficiency {#adrenal_insufficiency}
Adrenal insufficiency (the deficiency of glucocorticoids) occurs in about 5 in 10,000 in the general population. Diseases classified as *primary adrenal insufficiency* (including Addison\'s disease and genetic causes) directly affect the adrenal cortex. If a problem that affects the hypothalamic--pituitary--adrenal axis arises outside the gland, it is a *secondary adrenal insufficiency*.
#### Addison\'s disease {#addisons_disease}
Addison\'s disease refers to primary hypoadrenalism, which is a deficiency in glucocorticoid and mineralocorticoid production by the adrenal gland. In the Western world, Addison\'s disease is most commonly an autoimmune condition, in which the body produces antibodies against cells of the adrenal cortex. Worldwide, the disease is more frequently caused by infection, especially from tuberculosis. A distinctive feature of Addison\'s disease is hyperpigmentation of the skin, which presents with other nonspecific symptoms such as fatigue.
A complication seen in untreated Addison\'s disease and other types of primary adrenal insufficiency is the adrenal crisis, a medical emergency in which low glucocorticoid and mineralocorticoid levels result in hypovolemic shock and symptoms such as vomiting and fever. An adrenal crisis can progressively lead to stupor and coma. The management of adrenal crises includes the application of hydrocortisone injections.
#### Secondary adrenal insufficiency {#secondary_adrenal_insufficiency}
In secondary adrenal insufficiency, a dysfunction of the hypothalamic--pituitary--adrenal axis leads to decreased stimulation of the adrenal cortex. Apart from suppression of the axis by glucocorticoid therapy, the most common cause of secondary adrenal insufficiency are tumors that affect the production of adrenocorticotropic hormone (ACTH) by the pituitary gland. This type of adrenal insufficiency usually does not affect the production of mineralocorticoids, which are under regulation of the renin--angiotensin system instead.
#### Congenital adrenal hyperplasia {#congenital_adrenal_hyperplasia}
Congenital adrenal hyperplasia is a family of congenital diseases in which mutations of enzymes that produce steroid hormones result in a glucocorticoid deficiency and malfunction of the negative feedback loop of the HPA axis. In the HPA axis, cortisol (a glucocorticoid) inhibits the release of CRH and ACTH, hormones that in turn stimulate corticosteroid synthesis. As cortisol cannot be synthesized, these hormones are released in high quantities and stimulate production of other adrenal steroids instead. The most common form of congenital adrenal hyperplasia is due to 21-hydroxylase deficiency. 21-hydroxylase is necessary for production of both mineralocorticoids and glucocorticoids, but not androgens. Therefore, ACTH stimulation of the adrenal cortex induces the release of excessive amounts of adrenal androgens, which can lead to the development of ambiguous genitalia and secondary sex characteristics.
### Adrenal tumors {#adrenal_tumors}
*Main article: Adrenal tumor* Adrenal tumors are commonly found as incidentalomas, unexpected asymptomatic tumors found during medical imaging. They are seen in around 3.4% of CT scans, and in most cases they are benign adenomas. Adrenal carcinomas are very rare, with an incidence of 1 case per million per year.
Pheochromocytomas are tumors of the adrenal medulla that arise from chromaffin cells. They can produce a variety of nonspecific symptoms, which include headaches, sweating, anxiety and palpitations. Common signs include hypertension and tachycardia. Surgery, especially adrenal laparoscopy, is the most common treatment for small pheochromocytomas.
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# Adrenal gland
## History
Bartolomeo Eustachi, an Italian anatomist, is credited with the first description of the adrenal glands in 1563--4. However, these publications were part of the papal library and did not receive public attention, which was first received with Caspar Bartholin the Elder\'s illustrations in 1611.
The adrenal glands are named for their location relative to the kidneys. The term \"adrenal\" comes from Latin *ad*, \"near\", and *ren*, \"kidney\". Similarly, \"suprarenal\", as termed by Jean Riolan the Younger in 1629, is derived from the Latin *supra*, \"above\", and *ren*, \"kidney\", as well. The suprarenal nature of the glands was not truly accepted until the 19th century, as anatomists clarified the ductless nature of the glands and their likely secretory role -- prior to this, there was some debate as to whether the glands were indeed suprarenal or part of the kidney.
One of the most recognized works on the adrenal glands came in 1855 with the publication of *On the Constitutional and Local Effects of Disease of the Suprarenal Capsule*, by the English physician Thomas Addison. In his monography, Addison described what the French physician George Trousseau would later name Addison\'s disease, an eponym still used today for a condition of adrenal insufficiency and its related clinical manifestations. In 1894, English physiologists George Oliver and Edward Schafer studied the action of adrenal extracts and observed their pressor effects. In the following decades several physicians experimented with extracts from the adrenal cortex to treat Addison\'s disease. Edward Calvin Kendall, Philip Hench and Tadeusz Reichstein were then awarded the 1950 Nobel Prize in Physiology or Medicine for their discoveries on the structure and effects of the adrenal hormones
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# Saint Titus
**Titus** (`{{IPAc-en|ˈ|t|aɪ|t|ə|s}}`{=mediawiki} `{{respell|TY|təs}}`{=mediawiki}; *Τίτος*, *Títos*) was an early Christian missionary and church leader, a companion and disciple of Paul the Apostle, mentioned in several of the Pauline epistles including the Epistle to Titus. He is believed to be a Gentile converted to Christianity by Paul and, according to tradition, he was consecrated as Bishop of the Island of Crete.
Titus brought a fundraising letter from Paul to Corinth, to collect for the poor in Jerusalem. According to Jerome, Titus was the amanuensis of this epistle (2 Corinthians). Later, on Crete, Titus appointed presbyters (elders) in every city and remained there into his old age, dying in Gortyna.
## Life
Titus was a Greek, who may have studied Greek philosophy and poetry in his early years. He seems to have been converted by Paul, whereupon he served as Paul\'s secretary and interpreter. In the year 48 or 49 CE, Titus accompanied Paul to the council held at Jerusalem, on the subject of the Mosaic rites.
In the fall of 55 or 56 CE, Paul, as he himself departed from Asia, sent Titus from Ephesus to Corinth, with full commission to remedy the fallout precipitated by Timothy\'s delivery of 1 Corinthians and Paul\'s \"Painful Visit\", particularly a significant personal offense and challenge to Paul\'s authority by one unnamed individual. During this journey, Titus served as the courier for what is commonly known as the \"Severe Letter\", a Pauline missive that has been lost but is referred to in `{{Bibleverse|2 Corinthians|7:8-9|NIV}}`{=mediawiki}.
After success on this mission, Titus journeyed north and met Paul in Macedonia. There the apostle, overjoyed by Titus\' success, wrote 2 Corinthians. Titus then returned to Corinth with a larger entourage, carrying 2 Corinthians with him. Paul joined Titus in Corinth later. From Corinth, Paul then sent Titus to organize the collections of alms for the Christians at Jerusalem. Titus was therefore a troubleshooter, peacemaker, ecclesiastical administrator, and missionary.
Early church tradition holds that Paul, after his release from his first imprisonment in Rome, stopped at the island of Crete to preach. Due to the needs of other churches, requiring his presence elsewhere, he ordained his disciple Titus as bishop of that island, and left him to finish the work he had started. John Chrysostom says that this is an indication of the esteem Paul held for Titus.
Paul summoned Titus from Crete to join him at Nicopolis in Epirus. Later, Titus traveled to Dalmatia. The New Testament does not record his death.
## Identification with Timothy {#identification_with_timothy}
It has been argued that the name \"Titus\" in 2 Corinthians and Galatians was an informal name used by Timothy, a view circumstantially supported by the fact that both are said to be long-term close companions of Paul, even though they never appear together in these books. The theory proposes that a number of passages (1 Corinthians 4:17, 16.10; 2 Corinthians 2:13, 7:6, 13--14, 12:18; and Acts 19.22) refer to the same journey of a single individual, variously called Titus and Timothy. In support of this position, some draw on the fourth-century commentaries of Gaius Marius Victorinus.
Of course conjecture based upon a fourth century commentary or church tradition does not carry the weight of Scripture. `{{Bibleverse||Galatians|2:3}}`{=mediawiki} indicates that Titus, an uncircumcised Gentile believer, was with Paul in Antioch before the first apostolic mission, and that neither Paul nor Barnabas nor the apostles in Jerusalem compelled Titus to be circumcised when he went with Paul and Barnabas to Jerusalem. (Galatians 2:1-10). Secondly, Paul met Timothy much later, on his 2nd apostolic mission (Acts 16:1-3). When Timothy joined the apostolic team in Lystra, he was circumcised in `{{Bibleverse|Acts|16:3|NIV}}`{=mediawiki}. Also, the name Titus is a Latin name, while Timothy is a Greek name. Quite possibly Titus was a Roman, while Timothy was the son of a Greek father and a Jewish mother (Acts 16:1). Finally and conclusively, in `{{Bibleverse|2 Timothy|4:10|NIV}}`{=mediawiki}, Paul tells Timothy that Titus has departed to Dalmatia. Clearly they are different men.
## Veneration
Titus was venerated as a saint earlier than 261 CE. The feast day of Titus was not included in the Tridentine calendar. When added in 1854, it was assigned to 6 February. In 1969, the Catholic Church assigned the feast to 26 January so as to celebrate the two disciples of Paul, Titus and Timothy, the day after the feast of the Conversion of St. Paul. The Evangelical Lutheran Church in America celebrates these two, together with Silas, on the same date while he is honored on the calendars of the Church of England and Episcopal Church (with Timothy) on 26 January.
The Eastern Orthodox Church commemorates Titus on 25 August and on 4 January. His relics, now consisting of only his skull, are venerated in the Church of St. Titus, Heraklion, Crete, to which it was returned in 1966
after being removed to Venice during the period of Ottoman Crete (1667--1898).
Titus is the patron saint of the United States Army Chaplain Corps
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# Anita Hill
**Anita Faye Hill** (born July 30, 1956) is an American lawyer, educator and author. She is a professor of social policy, law, and women\'s studies at Brandeis University and a faculty member of the university\'s Heller School for Social Policy and Management. She became a national figure in 1991 when she accused U.S. Supreme Court nominee Clarence Thomas, her supervisor at the United States Department of Education and the Equal Employment Opportunity Commission, of sexual harassment.
## Early life and education {#early_life_and_education}
Anita Hill was born to a family of farmers in Lone Tree, Oklahoma, the youngest of Albert and Erma Hill\'s 13 children. Her family came from Arkansas, where her maternal grandfather Henry Eliot and all of her great-grandparents had been born into slavery. Hill was raised in the Baptist faith.
Hill graduated from Morris High School, Oklahoma, in 1973, where she was class valedictorian. Hill received her bachelor\'s degree in psychology in 1977 from Oklahoma State University. In 1980, she earned her Juris Doctor from Yale Law School in New Haven, Connecticut.
## Early career {#early_career}
Hill was admitted to the District of Columbia Bar in 1980 and began her law career as an associate with the Washington, D.C. firm of Wald, Harkrader & Ross. In 1981, she became an attorney-adviser to Clarence Thomas, who was then the Assistant Secretary of the U.S. Department of Education\'s Office for Civil Rights. When Thomas became chairman of the U.S. Equal Employment Opportunity Commission (EEOC) in 1982, Hill served as his assistant, leaving the job in 1983.
Hill then became an assistant professor at the Evangelical Christian O. W. Coburn School of Law at Oral Roberts University where she taught from 1983 to 1986. In 1986, she joined the faculty at the University of Oklahoma College of Law where she taught commercial law and contracts.
In 1989, she became the first tenured African American professor at OU. She left the university in 1996 due to ongoing calls for her resignation that began after her 1991 testimony. In 1998, she became a visiting scholar at Brandeis University and, in 2015, a university professor at the school.
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# Anita Hill
## Allegations of sexual harassment against Clarence Thomas {#allegations_of_sexual_harassment_against_clarence_thomas}
In 1991, President George H. W. Bush nominated Clarence Thomas, a federal circuit judge, to succeed retiring Associate Supreme Court Justice Thurgood Marshall. Senate hearings on his confirmation were initially completed with Thomas\'s good character being presented as a primary qualification for the high court because he had been a judge for just slightly more than one year. There had been little organized opposition to Thomas\'s nomination, and his confirmation seemed assured until a report of a private interview of Hill by the FBI was leaked to the press. The hearings were then reopened, and Hill was called to testify publicly.
Hill said on October 11, 1991, in televised hearings that Thomas had sexually harassed her while he was her supervisor at the Department of Education and the EEOC. When questioned on why she followed Thomas to the second job after he had already allegedly harassed her, she said working in a reputable position within the civil rights field had been her ambition. The position was appealing enough to keep her from going back into private practice with her previous firm. She said that she realized only later in her life that the choice had represented poor judgment on her part, but that \"at that time, it appeared that the sexual overtures\... had ended.\"
According to Hill, Thomas asked her out socially many times during her two years of employment as his assistant, and after she declined his requests, he used work situations to discuss sexual subjects and push advances. \"He spoke about\... such matters as women having sex with animals and films showing group sex or rape scenes,\" she said, adding that on several occasions Thomas graphically described \"his own sexual prowess\" and the details of his anatomy. Hill also recounted an instance in which Thomas examined a can of Coke on his desk and asked, \"Who has put pubic hair on my Coke?\" Thomas said he had considered Hill a friend whom he had helped at every turn, so when accusations of harassment came from her, they were particularly hurtful and he said, \"I lost the belief that if I did my best, all would work out.\"
Four female witnesses waited in the wings to support Hill\'s credibility, but they were not called, due to what the *Los Angeles Times* described as a private, compromise deal between Republicans and the Senate Judiciary Committee chair, Democrat Joe Biden.
Hill agreed to take a polygraph test. While senators and other authorities observed that polygraph results cannot be relied upon and are inadmissible in courts, Hill\'s results did support her statements. Thomas did not take a polygraph test. He made a vehement and complete denial, saying that he was being subjected to a \"high-tech lynching for uppity blacks\" by white liberals who were seeking to block a black conservative from taking a seat on the Supreme Court. After extensive debate, the United States Senate confirmed Thomas to the Supreme Court by a vote of 52--48, the narrowest margin since the 19th century.
Members questioned Hill\'s credibility after the timeline of her events came into question. They mentioned the time delay of ten years between the alleged behavior by Thomas and Hill\'s accusations, and observed that Hill had followed Thomas to a second job and later had personal contacts with Thomas, including giving him a ride to an airport --- behavior which they said would be inexplicable if Hill\'s allegations were true. Hill countered that she had come forward because she felt an obligation to share information on the character and actions of a person who was being considered for the Supreme Court. She testified that after leaving the EEOC, she had had two \"inconsequential\" phone conversations with Thomas, and had seen him personally on two occasions, once to get a job reference and the second time when he made a public appearance in Oklahoma where she was teaching.
Doubts about the veracity of Hill\'s 1991 testimony persisted among conservatives long after Thomas took his seat on the Court. They were furthered by right-wing magazine *American Spectator* writer David Brock in his 1993 book *The Real Anita Hill*, though he later recanted the claims he had made which he described in his book as \"character assassination,\" and apologized to Hill. After interviewing a number of women who alleged that Thomas had frequently subjected them to sexually explicit remarks, *The Wall Street Journal* reporters Jane Mayer and Jill Abramson wrote, *Strange Justice: The Selling of Clarence Thomas*, a book that concluded that Thomas had lied during his confirmation process. Richard Lacayo in his 1994 review of the book for *Time* magazine remarked, however, that \"Their book doesn\'t quite nail that conclusion.\" In 2007, Kevin `{{sic|hide=y|Merida}}`{=mediawiki}, a co-author of another book on Thomas, remarked that what happened between Thomas and Hill was \"ultimately unknowable\" by others, but that it was clear that \"one of them lied, period.\" Writing in 2007, Neil Lewis of *The New York Times* remarked that, \"To this day, each side in the epic he-said, she-said dispute has its unmovable believers.\"
In 2007, Thomas published his autobiography, *My Grandfather\'s Son*, in which he revisited the controversy, calling Hill his \"most traitorous adversary\", and writing that pro-choice liberals, who feared he would vote to overturn *Roe v. Wade* if he were seated on the Supreme Court, used the scandal against him. He described Hill as touchy and apt to overreact, and her work at the EEOC as mediocre. He acknowledged that three other former EEOC employees had backed Hill\'s story, but said they had all left the agency on bad terms. He also wrote that Hill \"was a left-winger who\'d never expressed any religious sentiments whatsoever \... and the only reason why she\'d held a job in the Reagan administration was because I\'d given it to her.\" Hill denied the accusations in an op-ed in *The New York Times* saying she would not \"stand by silently and allow \[Justice Thomas\], in his anger, to reinvent me.\"
In October 2010, Thomas\'s wife Virginia, a conservative activist, left a voicemail at Hill\'s office asking that Hill apologize for her 1991 testimony. Hill initially believed the call was a hoax and referred the matter to the Brandeis University campus police who alerted the FBI. After being informed that the call was indeed from Virginia Thomas, Hill told the media that she did not believe the message was meant to be conciliatory and said, \"I testified truthfully about my experience and I stand by that testimony.\" Virginia Thomas responded that the call had been intended as an \"olive branch\".
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# Anita Hill
## Allegations of sexual harassment against Clarence Thomas {#allegations_of_sexual_harassment_against_clarence_thomas}
### Effects
Shortly after the Thomas confirmation hearings, President George H. W. Bush dropped his opposition to a bill that gave harassment victims the right to seek federal damage awards, back pay, and reinstatement, and the law was passed by Congress. One year later, harassment complaints filed with the EEOC were up 50 percent and public opinion had shifted in Hill\'s favor. Private companies also started training programs to deter sexual harassment. When journalist Cinny Kennard asked Hill in 1991 if she would testify against Thomas all over again, Hill answered, \"I\'m not sure if I could have lived with myself if I had answered those questions any differently.\"
The manner in which the Senate Judiciary Committee challenged and dismissed Hill\'s accusations of sexual harassment angered female politicians and lawyers. According to D.C. Congressional Delegate Eleanor Holmes Norton, Hill\'s treatment by the panel was a contributing factor to the large number of women elected to Congress in 1992. \"Women clearly went to the polls with the notion in mind that you had to have more women in Congress,\" she said. In their anthology, *All the Women Are White, All the Blacks Are Men, but Some of Us Are Brave*, editors Gloria T. Hull, Patricia Bell-Scott, and Barbara Smith described black feminists mobilizing \"a remarkable national response to the Anita Hill--Clarence Thomas controversy. In 1992, a feminist group began a nationwide fundraising campaign and then obtained matching state funds to endow a professorship at the University of Oklahoma College of Law in honor of Hill. Conservative Oklahoma state legislators reacted by demanding Hill\'s resignation from the university, then introducing a bill to prohibit the university from accepting donations from out-of-state residents, and finally attempting to pass legislation to close down the law school. Elmer Zinn Million, a local activist, compared Hill to Lee Harvey Oswald, the assassin of President Kennedy. Certain officials at the university attempted to revoke Hill\'s tenure. After five years of pressure, Hill resigned. The University of Oklahoma Law School defunded the Anita F. Hill professorship in May 1999, without the position having ever been filled.
On April 25, 2019, the presidential campaign team for Joe Biden for the 2020 United States presidential election disclosed that he had called Hill to express \"his regret for what she endured\" in his role as the chairman of the Senate Judiciary Committee, presiding over the Thomas confirmation hearings. Hill said the call from Biden left her feeling \"deeply unsatisfied\". On June 13, 2019, Hill clarified that she did not consider Biden\'s actions disqualifying, and would be open to voting for him. In May 2020, Hill argued that sexual assault allegations made against Donald Trump as well as the sexual assault allegation against Biden should be investigated and their results \"made available to the public.\"
On September 5, 2020, it was reported that Hill had vowed to vote for Biden and to work with him on gender issues.
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# Anita Hill
## Continued work and advocacy {#continued_work_and_advocacy}
left\|thumb\|upright=.8\|Hill in 2014 speaking at Harvard Law School
Hill continued to teach at the University of Oklahoma, though she spent two years as a visiting professor in California. She resigned her post in October 1996 and finished her final semester of teaching there. In her final semester, she taught a law school seminar on civil rights. An endowed chair was created in her name, but was later defunded without ever having been filled.
Hill accepted a position as a visiting scholar at the Institute for the Study of Social Change at University of California, Berkeley in January 1997, but soon joined the faculty of Brandeis University---first at the Women\'s Studies Program, later moving to the Heller School for Social Policy and Management. In 2011, she also took a counsel position with the Civil Rights & Employment Practice group of the plaintiffs\' law firm Cohen Milstein.
Over the years, Hill has provided commentary on gender and race issues on national television programs, including *60 Minutes*, *Face the Nation*, and *Meet the Press*. She has been a speaker on the topic of commercial law as well as race and women\'s rights. She is also the author of articles that have been published in *The New York Times* and *Newsweek* and has contributed to many scholarly and legal publications in the areas of international commercial law, bankruptcy, and civil rights.
In 1995, Hill co-edited *Race, Gender and Power in America: The Legacy of the Hill-Thomas Hearings* with Emma Coleman Jordan. In 1997 Hill published her autobiography, *Speaking Truth to Power*, in which she chronicled her role in the Clarence Thomas confirmation controversy and wrote that creating a better society had been a motivating force in her life. She contributed the piece \"The Nature of the Beast: Sexual Harassment\" to the 2003 anthology *Sisterhood Is Forever: The Women\'s Anthology for a New Millennium*, edited by Robin Morgan. In 2011, Hill published her second book, *Reimagining Equality: Stories of Gender, Race, and Finding Home*, which focuses on the sub-prime lending crisis that resulted in the foreclosure of many homes owned by African-Americans. She calls for a new understanding about the importance of a home and its place in the American Dream. On March 26, 2015, the Brandeis Board of Trustees unanimously voted to recognize Hill with a promotion to Private University Professor of Social Policy, Law, and Women\'s Studies.
On December 16, 2017, the Commission on Sexual Harassment and Advancing Equality in the Workplace was formed, selecting Hill to lead its charge against sexual harassment in the entertainment industry. The new initiative was spearheaded by co-chair of the Nike Foundation Maria Eitel, venture capitalist Freada Kapor Klein, Lucasfilm President Kathleen Kennedy and talent attorney Nina Shaw. The report found not only a saddening prevalence of continued bias but also stark differences in how varying demographics perceived discrimination and harassment.
In September 2018, Hill wrote an op-ed in *The New York Times* regarding sexual assault allegations made by Christine Blasey Ford during the Brett Kavanaugh Supreme Court nomination. On November 8, 2018, Anita Hill spoke at the USC Dornsife\'s event, \"From Social Movement to Social Impact: Putting an End to Sexual Harassment in the Workplace\".
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# Anita Hill
## Writings
In 1994, Hill wrote a tribute to Thurgood Marshall, the first African American Supreme Court Justice who preceded Clarence Thomas, titled \"A Tribute to Thurgood Marshall: A Man Who Broke with Tradition on Issues of Race and Gender\". She outlined Marshall\'s contributions to the principles of equality as a judge and how his work has affected the lives of African Americans, specifically African American women.
On October 20, 1998, Hill published the book *Speaking Truth to Power*. Throughout much of the book she gives details on her side of the sexual harassment controversy, and her professional relationship with Clarence Thomas. Aside from that, she also provides a glimpse of what her personal life was like all the way from her childhood days growing up in Oklahoma to her position as a law professor.`{{page needed|date=November 2016}}`{=mediawiki}
Hill became a proponent for women\'s rights and feminism. This can be seen through the chapter she wrote in the 2007 book *Women and leadership: the state of play and strategies for change*. She wrote about women judges and why, in her opinion, they play such a large role in balancing the judicial system. She argues that since women and men have different life experiences, ways of thinking, and histories, both are needed for a balanced court system. She writes that in order for the best law system to be created in the United States, all people need the ability to be represented.
In 2011, Hill\'s second book, *Reimagining Equality: Stories of Gender, Race, and Finding Home* was published. She discusses the relationship between the home and the American Dream. She also exposes the inequalities within gender and race and home ownership. She argues that inclusive democracy is more important than debates about legal rights. She uses her own history and history of other African American women such as Nannie Helen Burroughs, in order to strengthen her argument for reimagining equality altogether.
On September 28, 2021, Hill published the book *Believing: Our Thirty-Year Journey to End Gender Violence*.
## Awards and recognition {#awards_and_recognition}
Hill received the American Bar Association\'s Commission on Women in the Profession\'s \"Women of Achievement\" award in 1992. In 2005, Hill was selected as a Fletcher Foundation Fellow. In 2008 she was awarded the Louis P. and Evelyn Smith First Amendment Award by the Ford Hall Forum. She also serves on the board of trustees for Southern Vermont College in Bennington, Vermont. She was inducted into the Oklahoma Women\'s Hall of Fame in 1993. On January 7, 2017, Hill was inducted as an honorary member of Zeta Phi Beta sorority at their National Executive Board Meeting in Dallas, Texas. The Wing\'s Washington, D.C. location has a phone booth dedicated to Hill.
Minor planet 6486 Anitahill, discovered by Eleanor Helin, is named in her honor. The official naming citation was published by the Minor Planet Center on November 8, 2019 (`{{small|[[Minor Planet Circulars|M.P.C.]] 117229}}`{=mediawiki}).
### Honorary doctorates {#honorary_doctorates}
- 2001: Simmons University
- 2001: Dillard University
- 2003: Smith College
- 2007: Lasell University
- 2008: Massachusetts College of Liberal Arts
- 2013: Mount Ida College
- 2017: Emerson College
- 2018: Wesleyan University
- 2019: Lesley University
- 2022: Mount Holyoke College
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# Anita Hill
## In popular culture {#in_popular_culture}
- In 1991, the television sitcom *Designing Women* built its episode \"The Strange Case of Clarence and Anita\" around the hearings on the Clarence Thomas nomination. The following season in the episode \"The Odyssey\", the characters imagined what would happen if new president Bill Clinton nominated Anita Hill to the Supreme Court to sit next to Clarence Thomas.
- Hill is referenced in the 1992 Sonic Youth song \"Youth Against Fascism.\"
- Her case also inspired the 1994 *Law & Order* episode \"Virtue\", about a young lawyer who feels pressured to sleep with her supervisor at her law firm.
- In the 1996 television film, *Hostile Advances: The Kerry Ellison Story*, Anita Hill\'s testimony is being watched at the bar by main character Kerry Ellison. The film is a true story about a landmark sexual harassment case.
- Anita Hill is mentioned in *The X-Files* episode \"Musings of a Cigarette Smoking Man\", which aired November 17, 1996.
- In the 1996 film *Jerry Maguire*, after Tom Cruise\'s character makes a pass at his employee (played by Renee Zellweger), he apologizes with, \"I feel like Clarence Thomas.\"
- In 1999, Ernest Dickerson directed *Strange Justice*, a film based on the Anita Hill--Clarence Thomas controversy.
- Anita Hill is interviewed -- unrelated to the Clarence Thomas case -- about the film *The Tin Drum* in the documentary *Banned in Oklahoma* (2004), included in The Criterion Collection DVD of the film (2004).
- Hill\'s testimony is briefly shown in the 2005 film *North Country* about the first class action lawsuit surrounding sexual harassment.
- Hill was the subject of the 2013 documentary film *Anita* by director Freida Lee Mock, which chronicles her experience during the Clarence Thomas scandal.
- The actor Kerry Washington portrayed Hill in the 2016 HBO film *Confirmation*.
- In 2018, entertainer John Oliver interviewed Hill on his television program *Last Week Tonight* during which Hill answered various questions and concerns about workplace sexual harassment in the present day.
- Hill has been interviewed by Stephen Colbert on *The Late Show* twice, once in 2018 and again in 2021
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# August 10
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# Audio signal processing
**Audio signal processing** is a subfield of signal processing that is concerned with the electronic manipulation of audio signals. Audio signals are electronic representations of sound waves---longitudinal waves which travel through air, consisting of compressions and rarefactions. The energy contained in audio signals or sound power level is typically measured in decibels. As audio signals may be represented in either digital or analog format, processing may occur in either domain. Analog processors operate directly on the electrical signal, while digital processors operate mathematically on its digital representation.
## History
The motivation for audio signal processing began at the beginning of the 20th century with inventions like the telephone, phonograph, and radio that allowed for the transmission and storage of audio signals. Audio processing was necessary for early radio broadcasting, as there were many problems with studio-to-transmitter links. The theory of signal processing and its application to audio was largely developed at Bell Labs in the mid 20th century. Claude Shannon and Harry Nyquist\'s early work on communication theory, sampling theory and pulse-code modulation (PCM) laid the foundations for the field. In 1957, Max Mathews became the first person to synthesize audio from a computer, giving birth to computer music.
Major developments in digital audio coding and audio data compression include differential pulse-code modulation (DPCM) by C. Chapin Cutler at Bell Labs in 1950, linear predictive coding (LPC) by Fumitada Itakura (Nagoya University) and Shuzo Saito (Nippon Telegraph and Telephone) in 1966, adaptive DPCM (ADPCM) by P. Cummiskey, Nikil S. Jayant and James L. Flanagan at Bell Labs in 1973, discrete cosine transform (DCT) coding by Nasir Ahmed, T. Natarajan and K. R. Rao in 1974, and modified discrete cosine transform (MDCT) coding by J. P. Princen, A. W. Johnson and A. B. Bradley at the University of Surrey in 1987. LPC is the basis for perceptual coding and is widely used in speech coding, while MDCT coding is widely used in modern audio coding formats such as MP3 and Advanced Audio Coding (AAC).
## Types
### Analog
An analog audio signal is a continuous signal represented by an electrical voltage or current that is *analogous* to the sound waves in the air. Analog signal processing then involves physically altering the continuous signal by changing the voltage or current or charge via electrical circuits.
Historically, before the advent of widespread digital technology, analog was the only method by which to manipulate a signal. Since that time, as computers and software have become more capable and affordable, digital signal processing has become the method of choice. However, in music applications, analog technology is often still desirable as it often produces nonlinear responses that are difficult to replicate with digital filters.
### Digital
A digital representation expresses the audio waveform as a sequence of symbols, usually binary numbers. This permits signal processing using digital circuits such as digital signal processors, microprocessors and general-purpose computers. Most modern audio systems use a digital approach as the techniques of digital signal processing are much more powerful and efficient than analog domain signal processing.
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# Audio signal processing
## Applications
Processing methods and application areas include storage, data compression, music information retrieval, speech processing, localization, acoustic detection, transmission, noise cancellation, acoustic fingerprinting, sound recognition, synthesis, and enhancement (e.g. equalization, filtering, level compression, echo and reverb removal or addition, etc.).
### Audio broadcasting {#audio_broadcasting}
Audio signal processing is used when broadcasting audio signals in order to enhance their fidelity or optimize for bandwidth or latency. In this domain, the most important audio processing takes place just before the transmitter. The audio processor here must prevent or minimize overmodulation, compensate for non-linear transmitters (a potential issue with medium wave and shortwave broadcasting), and adjust overall loudness to the desired level.
### Active noise control {#active_noise_control}
Active noise control is a technique designed to reduce unwanted sound. By creating a signal that is identical to the unwanted noise but with the opposite polarity, the two signals cancel out due to destructive interference.
### Audio synthesis {#audio_synthesis}
Audio synthesis is the electronic generation of audio signals. A musical instrument that accomplishes this is called a synthesizer. Synthesizers can either imitate sounds or generate new ones. Audio synthesis is also used to generate human speech using speech synthesis.
### Audio effects {#audio_effects}
Audio effects alter the sound of a musical instrument or other audio source. Common effects include distortion, often used with electric guitar in electric blues and rock music; dynamic effects such as volume pedals and compressors, which affect loudness; filters such as wah-wah pedals and graphic equalizers, which modify frequency ranges; modulation effects, such as chorus, flangers and phasers; pitch effects such as pitch shifters; and time effects, such as reverb and delay, which create echoing sounds and emulate the sound of different spaces.
Musicians, audio engineers and record producers use effects units during live performances or in the studio, typically with electric guitar, bass guitar, electronic keyboard or electric piano. While effects are most frequently used with electric or electronic instruments, they can be used with any audio source, such as acoustic instruments, drums, and vocals.
### Computer audition {#computer_audition}
Computer audition (CA) or machine listening is the general field of study of algorithms and systems for audio interpretation by machines. Since the notion of what it means for a machine to \"hear\" is very broad and somewhat vague, computer audition attempts to bring together several disciplines that originally dealt with specific problems or had a concrete application in mind. The engineer Paris Smaragdis, interviewed in *Technology Review*, talks about these systems {{\--}} \"software that uses sound to locate people moving through rooms, monitor machinery for impending breakdowns, or activate traffic cameras to record accidents.\"
Inspired by models of human audition, CA deals with questions of representation, transduction, grouping, use of musical knowledge and general sound semantics for the purpose of performing intelligent operations on audio and music signals by the computer. Technically this requires a combination of methods from the fields of signal processing, auditory modelling, music perception and cognition, pattern recognition, and machine learning, as well as more traditional methods of artificial intelligence for musical knowledge representation
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# April 27
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# Alfonso Leng
**Alfonso Leng Haygus** (11 February 1884 -- 11 November 1974) was a post-romantic composer of classical music. He was born in Santiago, Chile. He wrote the first important symphonic work in Chilean tradition, \"La Muerte de Alcino\", a symphonic poem inspired by the novel of Pedro Prado. He composed many art songs in different languages and important piano pieces, like the five \"Doloras\" (1914), which he later orchestrated and are normally played in concerts in Chile and Latin America. He won the National Art Prize in 1957.
Leng was also an accomplished dentist in Santiago. As a dentist, he was the main founder of the dentistry faculty of the University of Chile, and he was eventually elected as the first dean.
Leng was the nephew of composer Carmela Mackenna
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# Adamic language
The **Adamic language**, according to Jewish tradition (as recorded in the *midrashim*) and some Christians, is the language spoken by Adam (and possibly Eve) in the Garden of Eden. It is variously interpreted as either the language used by God to address Adam (the divine language), or the language invented by Adam with which he named all things (including Eve), as in the second Genesis creation narrative (`{{bibleverse|Genesis|2:19|KJV}}`{=mediawiki}).
In the Middle Ages, various Jewish commentators held that Adam spoke Hebrew, a view also addressed in various ways by the late medieval Italian poet Dante Alighieri. In the early modern period, some authors continued to discuss the possibility of an Adamic language, some continuing to hold to the idea that it was Hebrew, while others such as John Locke were more skeptical. According to Ethiopian and Eritrean traditions, the ancient Semitic language of Geʽez is the language of Adam, the first and original language. More recently, a variety of Mormon authors have expressed various opinions about the nature of the Adamic language.
## Patristic period {#patristic_period}
Augustine addresses the issue in *The City of God*. While not explicit, the implication of there being but one human language prior to the Tower of Babel\'s collapse is that the language, which was preserved by Heber and his son Peleg, and which is recognized as the language passed down to Abraham and his descendants, is the language that would have been used by Adam.
## Middle Ages {#middle_ages}
Traditional Jewish exegesis such as Midrash says that Adam spoke the Hebrew language because the names he gives Eve -- *Isha* and *Chava* -- only make sense in Hebrew. By contrast, Kabbalah assumed an \"eternal Torah\" which was not identical to the Torah written in Hebrew. Thus, Abraham Abulafia in the 13th century assumed that the language spoken in Paradise had been different from Hebrew, and rejected the claim then-current also among Christian authors, that a child left unexposed to linguistic stimulus would automatically begin to speak in Hebrew. Both Muslim and Christian Arabs, such as Sulayman al-Ghazzi, considered Syriac the language spoken by Adam and Eve.
Umberto Eco (1993) notes that Genesis is ambiguous on whether the language of Adam was preserved by Adam\'s descendants until the confusion of tongues, or if it began to evolve naturally even before Babel.
Dante Alighieri addresses the topic in his *De vulgari eloquentia* (1302--1305). He argues that the Adamic language is of divine origin and therefore unchangeable. He also notes that according to Genesis, the first speech act is due to Eve, addressing the serpent, and not to Adam.
In his *Divine Comedy* (c. 1308--1320), however, Dante changes his view to another that treats the Adamic language as the product of Adam. This had the consequence that it could no longer be regarded as immutable, and hence Hebrew could not be regarded as identical with the language of Paradise. Dante concludes (*Paradiso* XXVI) that Hebrew is a derivative of the language of Adam. In particular, the chief Hebrew name for God in scholastic tradition, *El*, must be derived of a different Adamic name for God, which Dante gives as *I*.
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# Adamic language
## Early modern period {#early_modern_period}
### Proponents
Elizabethan scholar John Dee makes references to a language he called \"Angelical\", which he recorded in his private journals and those of scryer Edward Kelley. Dee\'s journals did not describe the language as \"Enochian\", instead preferring \"Angelical\", the \"Celestial Speech\", the \"Language of Angels\", the \"First Language of God-Christ\", the \"Holy Language\", or \"Adamical\" because, according to Dee\'s Angels, it was used by Adam in Paradise to name all things. The language was later dubbed Enochian, due to Dee\'s assertion that the Biblical Patriarch Enoch had been the last human (before Dee and Kelley) to know the language.
Dutch physician, linguist, and humanist Johannes Goropius Becanus (1519--1572) theorized in *Origines Antwerpianae* (1569) that Antwerpian Babrantic, spoken in the region between the Scheldt and Meuse Rivers, was the original language spoken in Paradise. Goropius believed that the most ancient language on Earth would be the simplest language, and that the simplest language would contain mostly short words. Since Brabantic has a higher number of short words than do Latin, Greek, and Hebrew, Goropius reasoned that it was the older language. His work influenced that of Simon Stevin (1548--1620), who espoused similar ideas in \"Uytspraeck van de weerdicheyt der Duytse tael\", a chapter in *De Beghinselen Der Weeghconst* (1586).
### Opponents
By the 17th century, the existence and nature of the alleged Adamic language was commonly discussed amongst European Jewish and Christian mystics and primitive linguists. Robert Boyle (1627--1691) was skeptical that Hebrew was the language best capable of describing the nature of things, stating:
> I could never find, that the Hebrew names of animals, mentioned in the beginning of Genesis, argued a (much) clearer insight into their natures, than did the names of the same or some other animals in Greek, or other languages (1665:45).
John Locke (1632--1704) expressed similar skepticism in his *An Essay Concerning Human Understanding* (1690).
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# Adamic language
## Modern period {#modern_period}
### Latter Day Saint movement {#latter_day_saint_movement}
Joseph Smith, founder of the Latter Day Saint movement, in his revision of the Bible, declared the Adamic language to have been \"pure and undefiled\". Some Mormons believe it to be the language of God. Glossolalia, or speaking in tongues, was commonplace in the early years of the movement, and it was commonly believed that the incomprehensible language spoken during these incidents was the language of Adam. However, this belief seems to have never been formally or officially adopted.
Some other early Latter Day Saint leaders, including Brigham Young, Orson Pratt, and Elizabeth Ann Whitney, claimed to have received several words in the Adamic language by revelation. Some Latter Day Saints believe that the Adamic language is the \"pure language\" spoken of by Zephaniah and that it will be restored as the universal language of humankind at the end of the world.
Apostle Orson Pratt declared that \"Ahman\", part of the name of the settlement \"Adam-ondi-Ahman\" in Daviess County, Missouri, was the name of God in the Adamic language. An 1832 handwritten page from the Joseph Smith Papers, titled \"A Sample of the Pure Language\", and reportedly dictated by Smith to \"Br. Johnson\", asserts that the name of God is *Awman*.
The Latter Day Saint endowment prayer circle once included use of the words \"Pay Lay Ale\". These untranslated words are no longer used in temple ordinances and have been replaced by an English version, \"O God, hear the words of my mouth\". Some believe that the \"Pay Lay Ale\" sentence is derived from the Hebrew phrase \"pe le-El\" (*פה לאל*), \"mouth to God\". \"Pay Lay Ale\" was identified in the temple ceremony as words from the \"pure Adamic language\".
Other words thought by some Latter Day Saints to derive from the Adamic language include *deseret* (\"honey bee\") and *Ahman* (\"God\").
The Book of Moses refers to \"a book of remembrance\" written in the language of Adam.
### Goidelic languages {#goidelic_languages}
Nicholas Wolf writes that 19th-century Irish language speakers and publications claim that Irish (or some Goidelic language) is a language of Biblical primacy comparable to Hebrew, with some claiming it was the language of Adam.
## In popular culture {#in_popular_culture}
In the videogame *Indiana Jones and the Great Circle*, the language Adamic is discovered by the protagonist as an early human language spoken by giants, which was adapted into Egyptian and Sumerian in ancient times. It is also represented on stone tablets, resembling logographic writing systems of the early Bronze Age
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# Avery Hopwood
**James Avery Hopwood** (May 28, 1882 -- July 1, 1928) was an American playwright of the Jazz Age. He had four plays running simultaneously on Broadway in 1920, namely \"The Gold Diggers,\" \"The Bat\" and \"Spanish Love\" and \"Ladies\' Night (In a Turkish Bath)\".
## Early life {#early_life}
Hopwood was born to James and Jule Pendergast Hopwood on May 28, 1882, in Cleveland, Ohio. He graduated from Cleveland\'s West High School in 1900. In 1901, he began attending the University of Michigan in Ann Arbor. However, his family experienced financial difficulties, so for his second year he transferred to Adelbert College. He returned to the University of Michigan in the fall of 1903, and graduated Phi Beta Kappa in 1905.
## Career
Hopwood started out as a journalist for the *Cleveland Leader* as its New York correspondent, but within a year had his first play, *Clothes* (1906), produced on Broadway, with the aid of playwright Channing Pollock. Hopwood eventually became known as \"The Playboy Playwright\" and specialized in comedies and farces, some of them with material considered risqué at the time. One play, *The Demi-Virgin* in 1921, prompted a court case because of its suggestive subject matter, including a risque game of cards, \"Stripping Cupid\". The case was dismissed.
His many plays included *Nobody\'s Widow* (1910), starring Blanche Bates; *Fair and Warmer* (1915), starring Madge Kennedy (filmed in 1919); *The Gold Diggers* (1919), starring Ina Claire in New York and Tallulah Bankhead in London; (filmed in 1923 as *The Gold Diggers*, in 1928 as *Gold Diggers of Broadway* and also as *Gold Diggers of 1933*); *Ladies\' Night*, 1920, starring Charlie Ruggles (filmed in 1928); the famous mystery play *The Bat* (with Mary Roberts Rinehart), 1920 (filmed in 1926 as *The Bat*, in 1930 as *The Bat Whispers,* and in 1959 as *The Bat*); *Getting Gertie\'s Garter* (with Wilson Collison), 1921, starring Hazel Dawn (filmed in 1927 and 1945); *The Demi-Virgin*, 1921, also starring Dawn; *The Alarm Clock*, 1923, translated from the French; *The Best People* (with David Gray), 1924 (filmed in 1925 and as *Fast and Loose* in 1930 with Clara Bow); the song-farce *Naughty Cinderella*, 1925, starring Irène Bordoni and *The Garden of Eden* in 1927, with Tallulah Bankhead in London and Miriam Hopkins in New York; (filmed in 1928 as *The Garden of Eden*).
## Personal life {#personal_life}
In 1906, Hopwood was introduced to writer and photographer Carl Van Vechten. The two became close friends and were sometimes sexual partners. In the 1920s Hopwood had a tumultuous and abusive romantic relationship with fellow Cleveland-born playwright John Floyd. Although Hopwood announced to the press in 1924 that he was engaged to vaudeville dancer and choreographer Rosa Rolanda, Van Vechten confirmed in later years that it was a publicity stunt. Rolanda would later marry caricaturist Miguel Covarrubias.
On the evening of July 1, 1928, at Juan-les-Pins on the French Riviera, Hopwood suffered a fatal heart attack while swimming. He was buried in Riverside Cemetery, Cleveland. His mother, Jule Hopwood, inherited a large trust from him, but he had not made arrangements for the disposition of other items, including literary rights. While she was working through the legal issues with his estate, Jule Hopwood fell ill and died on March 1, 1929. She was buried next to her son.
## Legacy
Hopwood\'s plays were very successful commercially, but they did not have the lasting literary significance he hoped to achieve.
### Hopwood Award {#hopwood_award}
The terms of Hopwood\'s will left a substantial portion of his estate to his alma mater, the University of Michigan, for the establishment of the Avery Hopwood and Jule Hopwood Creative Writing Awards. The bequest stipulated: \"It is especially desired that students competing for prizes shall be allowed the widest possible latitude, and that the new, the unusual, and the radical shall be especially encouraged.\" Famous Hopwood award winners include Robert Hayden, Marge Piercy, Arthur Miller, Betty Smith, Lawrence Kasdan, John Ciardi, Mary Gaitskill, Edmund White, Nancy Willard, Frank O\'Hara, and Steve Hamilton.
### *The Great Bordello* {#the_great_bordello}
Throughout his life, Hopwood worked on a novel that he hoped would \"expose\" the strictures the commercial theater machine imposed on playwrights, but the manuscript was never published. Jack Sharrar recovered the manuscript for this novel in 1982 during his research for *Avery Hopwood, His Life and Plays*. The novel was published in July 2011 by Mondial Books (New York) as *The Great Bordello, a Story of the Theatre*, edited and with an Afterword by Sharrar
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# Antipope Felix II
**Antipope Felix II**, an Archdeacon of Rome, was installed as Pope in 355 AD after the Emperor Constantius II banished the reigning Pope, Liberius, for refusing to subscribe to a sentence of condemnation against Saint Athanasius.
## Biography
In May 357 AD the Roman laity, which had remained faithful to Liberius, demanded that Constantius, who was on a visit to Rome, should recall Liberius. The Emperor planned to have Felix and Liberius rule jointly, but when Liberius returned Felix was forced to retire to Porto, near Rome, where, after making an unsuccessful attempt to establish himself again in Rome, he died on 22 November 365 AD.
This Felix was later confused with a Roman martyr named Felix, with the result that he was included in lists of the Popes as Felix II and that the succeeding Popes of the same name (Pope Felix III and Pope Felix IV) were given wrong numerals, as was Antipope Felix V.
The Catholic Encyclopedia (1909) called this confusion a \"distortion of the true facts\" and suggested that it arose because the \"Liber Pontificalis\", which at this point may be registering a reliable tradition, says that this Felix built a church on the Via Aurelia, which is where the Roman martyr of an earlier date was buried. However, a more recent source says that of the martyr Felix nothing is known except his name, that he was a martyr, and that he was buried in the cemetery on the Via Portuensis that bears his name.
The Catholic Encyclopedia remarked that \"the real story of the antipope was lost and he obtained in local Roman history the status of a saint and a confessor. As such he appears in the Roman Martyrology on 29 July.\" At that time (1909) the Roman Martyrology had the following text: `{{quote|At Rome, on the Aurelian Way, St. Felix II, pope and martyr. Being expelled from his See by the Arian emperor Constantius for defending the Catholic faith, and being put to the sword privately at Cera in Tuscany, he died gloriously. His body was taken away from that place by clerics, and buried on the Aurelian Way. It was afterwards brought to the Church of the Saints Cosmas and Damian, where, under the Sovereign Pontiff [[Gregory XIII]], it was found beneath the altar with the relics of the holy martyrs [[Mark and Marcellian|Mark, Marcellian, and Tranquillinus]], and with the latter was put back in the same place on 31 July. In the same altar were also found the bodies of the holy martyrs Abundius, a priest, and Abundantius, a deacon, which were shortly after solemnly transferred to the church of the Society of Jesus, on the eve of their feast.}}`{=mediawiki} This entry was based on what the Catholic Encyclopedia called later legends that confound the relative positions of Felix and Liberius. More recent editions of the Roman Martyrology have instead: `{{quote|At Rome, at the third milestone on the Via Portuensis, in the cemetery dedicated to his name, Saint Felix, martyr.}}`{=mediawiki}
The feast day of the Roman martyr Felix is 29 July. The antipope Felix died, as stated above, on a 22 November, and his death was not a martyr\'s, occurring when the Peace of Constantine had been in force for half a century.
As well as the Roman Martyrology, the Roman Missal identified the Saint Felix of 29 July with the antipope. This identification, still found in the 1920 typical edition, does not appear in the 1962 typical edition. To judge by the Marietti printing of 1952, which omits the numeral \"II\" and the word \"Papae\", the correction had already been made by then. One Catholic writer excuses this by saying that the antipope \"himself did refuse to accept Arianism, and so his feast has been kept in the past on \[29 July\]\"
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# Alkaloid
**Alkaloids** are a broad class of naturally occurring organic compounds that contain at least one nitrogen atom. Some synthetic compounds of similar structure may also be termed alkaloids.
Alkaloids are produced by a large variety of organisms including bacteria, fungi, plants, and animals. They can be purified from crude extracts of these organisms by acid-base extraction, or solvent extractions followed by silica-gel column chromatography. Alkaloids have a wide range of pharmacological activities including antimalarial (e.g. quinine), antiasthma (e.g. ephedrine), anticancer (e.g. homoharringtonine), cholinomimetic (e.g. galantamine), vasodilatory (e.g. vincamine), antiarrhythmic (e.g. quinidine), analgesic (e.g. morphine), antibacterial (e.g. chelerythrine), and antihyperglycemic activities (e.g. berberine). Many have found use in traditional or modern medicine, or as starting points for drug discovery. Other alkaloids possess psychotropic (e.g. psilocin) and stimulant activities (e.g. cocaine, caffeine, nicotine, theobromine), and have been used in entheogenic rituals or as recreational drugs. Alkaloids can be toxic (e.g. atropine, tubocurarine). Although alkaloids act on a diversity of metabolic systems in humans and other animals, they almost uniformly evoke a bitter taste.
The boundary between alkaloids and other nitrogen-containing natural compounds is not clear-cut. Most alkaloids are basic, although some have neutral and even weakly acidic properties. In addition to carbon, hydrogen and nitrogen, alkaloids may also contain oxygen or sulfur. Rarer still, they may contain elements such as phosphorus, chlorine, and bromine. Compounds like amino acid peptides, proteins, nucleotides, nucleic acid, amines, and antibiotics are usually not called alkaloids.`{{r|GoldBook}}`{=mediawiki} Natural compounds containing nitrogen in the exocyclic position (mescaline, serotonin, dopamine, etc.) are usually classified as amines rather than as alkaloids. Some authors, however, consider alkaloids a special case of amines.
## Naming
The name \"alkaloids\" (*links=no*) was introduced in 1819 by German chemist Carl Friedrich Wilhelm Meissner, and is derived from late Latin root *alkali* and the Greek-language suffix *-οειδής* -(\'like\'). However, the term came into wide use only after the publication of a review article, by Oscar Jacobsen in the chemical dictionary of Albert Ladenburg in the 1880s.
There is no unique method for naming alkaloids. Many individual names are formed by adding the suffix \"ine\" to the species or genus name. For example, atropine is isolated from the plant *Atropa belladonna*; strychnine is obtained from the seed of the Strychnine tree (*Strychnos nux-vomica* L.). Where several alkaloids are extracted from one plant their names are often distinguished by variations in the suffix: \"idine\", \"anine\", \"aline\", \"inine\" etc. There are also at least 86 alkaloids whose names contain the root \"vin\" because they are extracted from *vinca* plants such as *Vinca rosea* (*Catharanthus roseus*); these are called *vinca* alkaloids.
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# Alkaloid
## History
Alkaloid-containing plants have been used by humans since ancient times for therapeutic and recreational purposes. For example, medicinal plants have been known in Mesopotamia from about 2000 BC. The *Odyssey* of Homer referred to a gift given to Helen by the Egyptian queen, a drug bringing oblivion. It is believed that the gift was an opium-containing drug. A Chinese book on houseplants written in 1st--3rd centuries BC mentioned a medical use of ephedra and opium poppies. Also, coca leaves have been used by Indigenous South Americans since ancient times.
Extracts from plants containing toxic alkaloids, such as aconitine and tubocurarine, were used since antiquity for poisoning arrows.
Studies of alkaloids began in the 19th century. In 1804, the German chemist Friedrich Sertürner isolated from opium a \"soporific principle\" (*links=no*), which he called \"morphium\", referring to Morpheus, the Greek god of dreams; in German and some other Central-European languages, this is still the name of the drug. The term \"morphine\", used in English and French, was given by the French physicist Joseph Louis Gay-Lussac.
A significant contribution to the chemistry of alkaloids in the early years of its development was made by the French researchers Pierre Joseph Pelletier and Joseph Bienaimé Caventou, who discovered quinine (1820) and strychnine (1818). Several other alkaloids were discovered around that time, including xanthine (1817), atropine (1819), caffeine (1820), coniine (1827), nicotine (1828), colchicine (1833), sparteine (1851), and cocaine (1860). The development of the chemistry of alkaloids was accelerated by the emergence of spectroscopic and chromatographic methods in the 20th century, so that by 2008 more than 12,000 alkaloids had been identified.
The first complete synthesis of an alkaloid was achieved in 1886 by the German chemist Albert Ladenburg. He produced coniine by reacting 2-methylpyridine with acetaldehyde and reducing the resulting 2-propenyl pyridine with sodium.
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# Alkaloid
## Classifications
Compared with most other classes of natural compounds, alkaloids are characterized by a great structural diversity. There is no uniform classification. Initially, when knowledge of chemical structures was lacking, botanical classification of the source plants was relied on. This classification is now considered obsolete.
More recent classifications are based on similarity of the carbon skeleton (*e.g.*, indole-, isoquinoline-, and pyridine-like) or biochemical precursor (ornithine, lysine, tyrosine, tryptophan, etc.). However, they require compromises in borderline cases; for example, nicotine contains a pyridine fragment from nicotinamide and a pyrrolidine part from ornithine and therefore can be assigned to both classes.
Alkaloids are often divided into the following major groups:
1. \"True alkaloids\" contain nitrogen in the heterocycle and originate from amino acids.\<ref
name=\"ref21\"\>Plemenkov, p. 223
Their characteristic examples are atropine, nicotine, and morphine. This group also includes some alkaloids that besides the nitrogen heterocycle contain terpene (*e.g.*, evonine) or peptide fragments (*e.g.* ergotamine). The piperidine alkaloids coniine and coniceine may be regarded as true alkaloids (rather than pseudoalkaloids: see below) although they do not originate from amino acids.
1. \"Protoalkaloids\", which contain nitrogen (but not the nitrogen heterocycle) and also originate from amino acids. Examples include mescaline, adrenaline and ephedrine.
2. Polyamine alkaloids -- derivatives of putrescine, spermidine, and spermine.
3. Peptide and cyclopeptide alkaloids.
4. Pseudoalkaloids -- alkaloid-like compounds that do not originate from amino acids. This group includes terpene-like and steroid-like alkaloids, as well as purine-like alkaloids such as caffeine, theobromine, theacrine and theophylline. Some authors classify ephedrine and cathinone as pseudoalkaloids. Those originate from the amino acid phenylalanine, but acquire their nitrogen atom not from the amino acid but through transamination.
Some alkaloids do not have the carbon skeleton characteristic of their group. So, galanthamine and homoaporphines do not contain isoquinoline fragment, but are, in general, attributed to isoquinoline alkaloids.
Main classes of monomeric alkaloids are listed in the table below:
+-----------------------------------------------------------------+----------------------------------------------------------------------------------------+------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------+------------------------------------------------------------------------------------------------------------------+
| Class | Major groups | Main synthesis steps | Examples |
+=================================================================+========================================================================================+================================================================================================================================================================================================+==================================================================================================================+
| *Alkaloids with nitrogen heterocycles (true alkaloids)* | | | |
+-----------------------------------------------------------------+----------------------------------------------------------------------------------------+------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------+------------------------------------------------------------------------------------------------------------------+
| Pyrrolidine derivatives | | Ornithine or arginine → putrescine → N-methylputrescine → N-methyl-Δ^1^-pyrroline | Cuscohygrine, hygrine, hygroline, stachydrine |
+-----------------------------------------------------------------+----------------------------------------------------------------------------------------+------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------+------------------------------------------------------------------------------------------------------------------+
| Tropane derivatives | Atropine group\ | Ornithine or arginine → putrescine → N-methylputrescine → N-methyl-Δ^1^-pyrroline | Atropine, scopolamine, hyoscyamine |
| | Substitution in positions 3, 6 or 7 | | |
+-----------------------------------------------------------------+----------------------------------------------------------------------------------------+------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------+------------------------------------------------------------------------------------------------------------------+
| Cocaine group\ | Cocaine, ecgonine | | |
| Substitution in positions 2 and 3 | | | |
+-----------------------------------------------------------------+----------------------------------------------------------------------------------------+------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------+------------------------------------------------------------------------------------------------------------------+
| Pyrrolizidine derivatives | Non-esters | In plants: ornithine or arginine → putrescine → homospermidine → retronecine | Retronecine, heliotridine, laburnine |
+-----------------------------------------------------------------+----------------------------------------------------------------------------------------+------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------+------------------------------------------------------------------------------------------------------------------+
| Complex esters of monocarboxylic acids | Indicine, lindelophin, sarracine | | |
+-----------------------------------------------------------------+----------------------------------------------------------------------------------------+------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------+------------------------------------------------------------------------------------------------------------------+
| Macrocyclic diesters | Platyphylline, trichodesmine | | |
+-----------------------------------------------------------------+----------------------------------------------------------------------------------------+------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------+------------------------------------------------------------------------------------------------------------------+
| 1-aminopyrrolizidines (lolines) | In fungi: L-proline + L-homoserine → *N*-(3-amino-3-carboxypropyl)proline → norloline | Loline, *N*-formylloline, *N*-acetylloline | |
+-----------------------------------------------------------------+----------------------------------------------------------------------------------------+------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------+------------------------------------------------------------------------------------------------------------------+
| Piperidine derivatives | | Lysine → cadaverine → Δ^1^-piperideine | Sedamine, lobeline, anaferine, piperine |
+-----------------------------------------------------------------+----------------------------------------------------------------------------------------+------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------+------------------------------------------------------------------------------------------------------------------+
| | Octanoic acid → coniceine → coniine | Coniine, coniceine | |
+-----------------------------------------------------------------+----------------------------------------------------------------------------------------+------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------+------------------------------------------------------------------------------------------------------------------+
| Quinolizidine derivatives | Lupinine group | Lysine → cadaverine → Δ^1^-piperideine | Lupinine, nupharidin |
+-----------------------------------------------------------------+----------------------------------------------------------------------------------------+------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------+------------------------------------------------------------------------------------------------------------------+
| Cytisine group | Cytisine | | |
+-----------------------------------------------------------------+----------------------------------------------------------------------------------------+------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------+------------------------------------------------------------------------------------------------------------------+
| Sparteine group | Sparteine, lupanine, anahygrine | | |
+-----------------------------------------------------------------+----------------------------------------------------------------------------------------+------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------+------------------------------------------------------------------------------------------------------------------+
| Matrine group. | Matrine, oxymatrine, allomatridine | | |
+-----------------------------------------------------------------+----------------------------------------------------------------------------------------+------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------+------------------------------------------------------------------------------------------------------------------+
| Ormosanine group | Ormosanine, piptantine | | |
+-----------------------------------------------------------------+----------------------------------------------------------------------------------------+------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------+------------------------------------------------------------------------------------------------------------------+
| Indolizidine derivatives | | Lysine → δ-semialdehyde of α-aminoadipic acid → pipecolic acid → 1 indolizidinone | Swainsonine, castanospermine |
+-----------------------------------------------------------------+----------------------------------------------------------------------------------------+------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------+------------------------------------------------------------------------------------------------------------------+
| Pyridine derivatives | Simple derivatives of pyridine | Nicotinic acid → dihydronicotinic acid → 1,2-dihydropyridine | Trigonelline, ricinine, arecoline |
+-----------------------------------------------------------------+----------------------------------------------------------------------------------------+------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------+------------------------------------------------------------------------------------------------------------------+
| Polycyclic noncondensing pyridine derivatives | Nicotine, nornicotine, anabasine, anatabine | | |
+-----------------------------------------------------------------+----------------------------------------------------------------------------------------+------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------+------------------------------------------------------------------------------------------------------------------+
| Polycyclic condensed pyridine derivatives | Actinidine, gentianine, pediculinine | | |
+-----------------------------------------------------------------+----------------------------------------------------------------------------------------+------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------+------------------------------------------------------------------------------------------------------------------+
| Sesquiterpene pyridine derivatives | Nicotinic acid, isoleucine | Evonine, hippocrateine, triptonine | |
+-----------------------------------------------------------------+----------------------------------------------------------------------------------------+------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------+------------------------------------------------------------------------------------------------------------------+
| Isoquinoline derivatives and related alkaloids | Simple derivatives of isoquinoline | Tyrosine or phenylalanine → dopamine or tyramine (for alkaloids Amarillis) | Salsoline, lophocerine |
+-----------------------------------------------------------------+----------------------------------------------------------------------------------------+------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------+------------------------------------------------------------------------------------------------------------------+
| Derivatives of 1- and 3-isoquinolines | N-methylcoridaldine, noroxyhydrastinine | | |
+-----------------------------------------------------------------+----------------------------------------------------------------------------------------+------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------+------------------------------------------------------------------------------------------------------------------+
| Derivatives of 1- and 4-phenyltetrahydroisoquinolines | Cryptostilin | | |
+-----------------------------------------------------------------+----------------------------------------------------------------------------------------+------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------+------------------------------------------------------------------------------------------------------------------+
| Derivatives of 5-naftil-isoquinoline | Ancistrocladine | | |
+-----------------------------------------------------------------+----------------------------------------------------------------------------------------+------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------+------------------------------------------------------------------------------------------------------------------+
| Derivatives of 1- and 2-benzyl-izoquinolines | Papaverine, laudanosine, sendaverine | | |
+-----------------------------------------------------------------+----------------------------------------------------------------------------------------+------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------+------------------------------------------------------------------------------------------------------------------+
| Cularine group | Cularine, yagonine | | |
+-----------------------------------------------------------------+----------------------------------------------------------------------------------------+------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------+------------------------------------------------------------------------------------------------------------------+
| Pavines and isopavines | Argemonine, amurensine | | |
+-----------------------------------------------------------------+----------------------------------------------------------------------------------------+------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------+------------------------------------------------------------------------------------------------------------------+
| Benzopyrrocolines | Cryptaustoline | | |
+-----------------------------------------------------------------+----------------------------------------------------------------------------------------+------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------+------------------------------------------------------------------------------------------------------------------+
| Protoberberines | Berberine, canadine, ophiocarpine, mecambridine, corydaline | | |
+-----------------------------------------------------------------+----------------------------------------------------------------------------------------+------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------+------------------------------------------------------------------------------------------------------------------+
| Phthalidisoquinolines | Hydrastine, narcotine (Noscapine) | | |
+-----------------------------------------------------------------+----------------------------------------------------------------------------------------+------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------+------------------------------------------------------------------------------------------------------------------+
| Spirobenzylisoquinolines | Fumaricine | | |
+-----------------------------------------------------------------+----------------------------------------------------------------------------------------+------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------+------------------------------------------------------------------------------------------------------------------+
| Ipecacuanha alkaloids | Emetine, protoemetine, ipecoside | | |
+-----------------------------------------------------------------+----------------------------------------------------------------------------------------+------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------+------------------------------------------------------------------------------------------------------------------+
| Benzophenanthridines | Sanguinarine, oxynitidine, corynoloxine | | |
+-----------------------------------------------------------------+----------------------------------------------------------------------------------------+------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------+------------------------------------------------------------------------------------------------------------------+
| Aporphines | Glaucine, coridine, liriodenine | | |
+-----------------------------------------------------------------+----------------------------------------------------------------------------------------+------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------+------------------------------------------------------------------------------------------------------------------+
| Proaporphines | Pronuciferine, glaziovine | | |
+-----------------------------------------------------------------+----------------------------------------------------------------------------------------+------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------+------------------------------------------------------------------------------------------------------------------+
| Homoaporphines | Kreysiginine, multifloramine | | |
+-----------------------------------------------------------------+----------------------------------------------------------------------------------------+------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------+------------------------------------------------------------------------------------------------------------------+
| Homoproaporphines | Bulbocodine | | |
+-----------------------------------------------------------------+----------------------------------------------------------------------------------------+------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------+------------------------------------------------------------------------------------------------------------------+
| Morphines | Morphine, codeine, thebaine, sinomenine, heroin | | |
+-----------------------------------------------------------------+----------------------------------------------------------------------------------------+------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------+------------------------------------------------------------------------------------------------------------------+
| Homomorphines | Kreysiginine, androcymbine | | |
+-----------------------------------------------------------------+----------------------------------------------------------------------------------------+------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------+------------------------------------------------------------------------------------------------------------------+
| Tropoloisoquinolines | Imerubrine | | |
+-----------------------------------------------------------------+----------------------------------------------------------------------------------------+------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------+------------------------------------------------------------------------------------------------------------------+
| Azofluoranthenes | Rufescine, imeluteine | | |
+-----------------------------------------------------------------+----------------------------------------------------------------------------------------+------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------+------------------------------------------------------------------------------------------------------------------+
| Amaryllis alkaloids | Lycorine, ambelline, tazettine, galantamine, montanine | | |
+-----------------------------------------------------------------+----------------------------------------------------------------------------------------+------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------+------------------------------------------------------------------------------------------------------------------+
| Erythrina alkaloids | Erysodine, erythroidine | | |
+-----------------------------------------------------------------+----------------------------------------------------------------------------------------+------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------+------------------------------------------------------------------------------------------------------------------+
| Phenanthrene derivatives | Atherosperminine | | |
+-----------------------------------------------------------------+----------------------------------------------------------------------------------------+------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------+------------------------------------------------------------------------------------------------------------------+
| Protopines | Protopine, oxomuramine, corycavidine | | |
+-----------------------------------------------------------------+----------------------------------------------------------------------------------------+------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------+------------------------------------------------------------------------------------------------------------------+
| Aristolactam | Doriflavin | | |
+-----------------------------------------------------------------+----------------------------------------------------------------------------------------+------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------+------------------------------------------------------------------------------------------------------------------+
| Oxazole derivatives | | Tyrosine → tyramine | Annuloline, halfordinol, texaline, texamine |
+-----------------------------------------------------------------+----------------------------------------------------------------------------------------+------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------+------------------------------------------------------------------------------------------------------------------+
| Isoxazole derivatives | | Ibotenic acid → Muscimol | Ibotenic acid, Muscimol |
+-----------------------------------------------------------------+----------------------------------------------------------------------------------------+------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------+------------------------------------------------------------------------------------------------------------------+
| Thiazole derivatives | | 1-Deoxy-D-xylulose 5-phosphate (DOXP), tyrosine, cysteine | Nostocyclamide, thiostreptone |
+-----------------------------------------------------------------+----------------------------------------------------------------------------------------+------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------+------------------------------------------------------------------------------------------------------------------+
| Quinazoline derivatives | 3,4-Dihydro-4-quinazolone derivatives | Anthranilic acid or phenylalanine or ornithine | Febrifugine |
+-----------------------------------------------------------------+----------------------------------------------------------------------------------------+------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------+------------------------------------------------------------------------------------------------------------------+
| 1,4-Dihydro-4-quinazolone derivatives | Glycorine, arborine, glycosminine | | |
+-----------------------------------------------------------------+----------------------------------------------------------------------------------------+------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------+------------------------------------------------------------------------------------------------------------------+
| Pyrrolidine and piperidine quinazoline derivatives | Vazicine (peganine) | | |
+-----------------------------------------------------------------+----------------------------------------------------------------------------------------+------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------+------------------------------------------------------------------------------------------------------------------+
| Acridine derivatives | | Anthranilic acid | Rutacridone, acronicine |
+-----------------------------------------------------------------+----------------------------------------------------------------------------------------+------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------+------------------------------------------------------------------------------------------------------------------+
| Quinoline derivatives | Simple derivatives of quinoline derivatives of 2--quinolones and 4-quinolone | Anthranilic acid → 3-carboxyquinoline | Cusparine, echinopsine, evocarpine |
+-----------------------------------------------------------------+----------------------------------------------------------------------------------------+------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------+------------------------------------------------------------------------------------------------------------------+
| Tricyclic terpenoids | Flindersine | | |
+-----------------------------------------------------------------+----------------------------------------------------------------------------------------+------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------+------------------------------------------------------------------------------------------------------------------+
| Furanoquinoline derivatives | Dictamnine, fagarine, skimmianine | | |
+-----------------------------------------------------------------+----------------------------------------------------------------------------------------+------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------+------------------------------------------------------------------------------------------------------------------+
| Quinines | Tryptophan → tryptamine → strictosidine (with secologanin) → korinanteal → cinhoninon | Quinine, quinidine, cinchonine, cinhonidine | |
+-----------------------------------------------------------------+----------------------------------------------------------------------------------------+------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------+------------------------------------------------------------------------------------------------------------------+
| Indole derivatives `{{See also|indole alkaloids}}`{=mediawiki} | *Non-isoprene indole alkaloids* | | |
+-----------------------------------------------------------------+----------------------------------------------------------------------------------------+------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------+------------------------------------------------------------------------------------------------------------------+
| Simple indole derivatives | Tryptophan → tryptamine or 5-Hydroxytryptophan | Serotonin, psilocybin, dimethyltryptamine (DMT), bufotenin | |
+-----------------------------------------------------------------+----------------------------------------------------------------------------------------+------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------+------------------------------------------------------------------------------------------------------------------+
| Simple derivatives of β-carboline | Harman, harmine, harmaline, eleagnine | | |
+-----------------------------------------------------------------+----------------------------------------------------------------------------------------+------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------+------------------------------------------------------------------------------------------------------------------+
| Pyrroloindole alkaloids | Physostigmine (eserine), etheramine, physovenine, eptastigmine | | |
+-----------------------------------------------------------------+----------------------------------------------------------------------------------------+------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------+------------------------------------------------------------------------------------------------------------------+
| *Semiterpenoid indole alkaloids* | | | |
+-----------------------------------------------------------------+----------------------------------------------------------------------------------------+------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------+------------------------------------------------------------------------------------------------------------------+
| Ergot alkaloids | Tryptophan → chanoclavine → agroclavine → elimoclavine → paspalic acid → lysergic acid | Ergotamine, ergobasine, ergosine | |
+-----------------------------------------------------------------+----------------------------------------------------------------------------------------+------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------+------------------------------------------------------------------------------------------------------------------+
| *Monoterpenoid indole alkaloids* | | | |
+-----------------------------------------------------------------+----------------------------------------------------------------------------------------+------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------+------------------------------------------------------------------------------------------------------------------+
| *Corynanthe* type alkaloids | Tryptophan → tryptamine → strictosidine (with secologanin) | Ajmalicine, sarpagine, vobasine, ajmaline, yohimbine, reserpine, mitragynine, group strychnine and (Strychnine brucine, aquamicine, vomicine) | |
+-----------------------------------------------------------------+----------------------------------------------------------------------------------------+------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------+------------------------------------------------------------------------------------------------------------------+
| Iboga-type alkaloids | Ibogamine, ibogaine, voacangine | | |
+-----------------------------------------------------------------+----------------------------------------------------------------------------------------+------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------+------------------------------------------------------------------------------------------------------------------+
| Aspidosperma-type alkaloids | Vincamine, *vinca* alkaloids, vincotine, aspidospermine | | |
+-----------------------------------------------------------------+----------------------------------------------------------------------------------------+------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------+------------------------------------------------------------------------------------------------------------------+
| Imidazole derivatives | | Directly from histidine | Histamine, pilocarpine, pilosine, stevensine |
+-----------------------------------------------------------------+----------------------------------------------------------------------------------------+------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------+------------------------------------------------------------------------------------------------------------------+
| Purine derivatives | | Xanthosine (formed in purine biosynthesis) → 7 methylxantosine → 7-methylxanthine → theobromine → caffeine | Caffeine, theobromine, theophylline, saxitoxin |
+-----------------------------------------------------------------+----------------------------------------------------------------------------------------+------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------+------------------------------------------------------------------------------------------------------------------+
| *Alkaloids with nitrogen in the side chain (protoalkaloids)* | | | |
+-----------------------------------------------------------------+----------------------------------------------------------------------------------------+------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------+------------------------------------------------------------------------------------------------------------------+
| β-Phenylethylamine derivatives | | Tyrosine or phenylalanine → dioxyphenilalanine → dopamine → adrenaline and mescaline tyrosine → tyramine phenylalanine → 1-phenylpropane-1,2-dione → cathinone → ephedrine and pseudoephedrine | Tyramine, ephedrine, pseudoephedrine, mescaline, cathinone, catecholamines (adrenaline, noradrenaline, dopamine) |
+-----------------------------------------------------------------+----------------------------------------------------------------------------------------+------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------+------------------------------------------------------------------------------------------------------------------+
| Colchicine alkaloids | | Tyrosine or phenylalanine → dopamine → autumnaline → colchicine | Colchicine, colchamine |
+-----------------------------------------------------------------+----------------------------------------------------------------------------------------+------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------+------------------------------------------------------------------------------------------------------------------+
| Muscarine | | Glutamic acid → 3-ketoglutamic acid → muscarine (with pyruvic acid) | Muscarine, allomuscarine, epimuscarine, epiallomuscarine |
+-----------------------------------------------------------------+----------------------------------------------------------------------------------------+------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------+------------------------------------------------------------------------------------------------------------------+
| Benzylamine | | Phenylalanine with valine, leucine or isoleucine | Capsaicin, dihydrocapsaicin, nordihydrocapsaicin, vanillylamine |
+-----------------------------------------------------------------+----------------------------------------------------------------------------------------+------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------+------------------------------------------------------------------------------------------------------------------+
| *Polyamines alkaloids* | | | |
+-----------------------------------------------------------------+----------------------------------------------------------------------------------------+------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------+------------------------------------------------------------------------------------------------------------------+
| Putrescine derivatives | | ornithine → putrescine → spermidine → spermine | Paucine |
+-----------------------------------------------------------------+----------------------------------------------------------------------------------------+------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------+------------------------------------------------------------------------------------------------------------------+
| Spermidine derivatives | | Lunarine, codonocarpine | |
+-----------------------------------------------------------------+----------------------------------------------------------------------------------------+------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------+------------------------------------------------------------------------------------------------------------------+
| Spermine derivatives | | Verbascenine, aphelandrine | |
+-----------------------------------------------------------------+----------------------------------------------------------------------------------------+------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------+------------------------------------------------------------------------------------------------------------------+
| *Peptide (cyclopeptide) alkaloids* | | | |
+-----------------------------------------------------------------+----------------------------------------------------------------------------------------+------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------+------------------------------------------------------------------------------------------------------------------+
| Peptide alkaloids with a 13-membered cycle | Nummularine C type | From different amino acids | Nummularine C, Nummularine S |
+-----------------------------------------------------------------+----------------------------------------------------------------------------------------+------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------+------------------------------------------------------------------------------------------------------------------+
| Ziziphine type | Ziziphine A, sativanine H | | |
+-----------------------------------------------------------------+----------------------------------------------------------------------------------------+------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------+------------------------------------------------------------------------------------------------------------------+
| Peptide alkaloids with a 14-membered cycle | Frangulanine type | Frangulanine, scutianine J | |
+-----------------------------------------------------------------+----------------------------------------------------------------------------------------+------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------+------------------------------------------------------------------------------------------------------------------+
| Scutianine A type | Scutianine A | | |
+-----------------------------------------------------------------+----------------------------------------------------------------------------------------+------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------+------------------------------------------------------------------------------------------------------------------+
| Integerrine type | Integerrine, discarine D | | |
+-----------------------------------------------------------------+----------------------------------------------------------------------------------------+------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------+------------------------------------------------------------------------------------------------------------------+
| Amphibine F type | Amphibine F, spinanine A | | |
+-----------------------------------------------------------------+----------------------------------------------------------------------------------------+------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------+------------------------------------------------------------------------------------------------------------------+
| Amfibine B type | Amphibine B, lotusine C | | |
+-----------------------------------------------------------------+----------------------------------------------------------------------------------------+------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------+------------------------------------------------------------------------------------------------------------------+
| Peptide alkaloids with a 15-membered cycle | Mucronine A type | Mucronine A | |
+-----------------------------------------------------------------+----------------------------------------------------------------------------------------+------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------+------------------------------------------------------------------------------------------------------------------+
| *Pseudoalkaloids (terpenes and steroids)* | | | |
+-----------------------------------------------------------------+----------------------------------------------------------------------------------------+------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------+------------------------------------------------------------------------------------------------------------------+
| Diterpenes | Lycoctonine type | Mevalonic acid → Isopentenyl pyrophosphate → geranyl pyrophosphate | Aconitine, delphinine |
+-----------------------------------------------------------------+----------------------------------------------------------------------------------------+------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------+------------------------------------------------------------------------------------------------------------------+
| Steroidal alkaloids | | Cholesterol, arginine | Solanidine, cyclopamine, batrachotoxin |
+-----------------------------------------------------------------+----------------------------------------------------------------------------------------+------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------+------------------------------------------------------------------------------------------------------------------+
## Properties
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# Alkaloid
## Properties
Most alkaloids contain oxygen in their molecular structure; those compounds are usually colorless crystals at ambient conditions. Oxygen-free alkaloids, such as nicotine or coniine, are typically volatile, colorless, oily liquids. Some alkaloids are colored, like berberine (yellow) and sanguinarine (orange).
Most alkaloids are weak bases, but some, such as theobromine and theophylline, are amphoteric. Many alkaloids dissolve poorly in water but readily dissolve in organic solvents, such as diethyl ether, chloroform or 1,2-dichloroethane. Caffeine, cocaine, codeine and nicotine are slightly soluble in water (with a solubility of ≥1g/L), whereas others, including morphine and yohimbine are very slightly water-soluble (0.1--1 g/L). Alkaloids and acids form salts of various strengths. These salts are usually freely soluble in water and ethanol and poorly soluble in most organic solvents. Exceptions include scopolamine hydrobromide, which is soluble in organic solvents, and the water-soluble quinine sulfate.
Most alkaloids have a bitter taste or are poisonous when ingested. Alkaloid production in plants appeared to have evolved in response to feeding by herbivorous animals; however, some animals have evolved the ability to detoxify alkaloids. Some alkaloids can produce developmental defects in the offspring of animals that consume but cannot detoxify the alkaloids. One example is the alkaloid cyclopamine, produced in the leaves of corn lily. During the 1950s, up to 25% of lambs born by sheep that had grazed on corn lily had serious facial deformations. These ranged from deformed jaws to cyclopia. After decades of research, in the 1980s, the compound responsible for these deformities was identified as the alkaloid 11-deoxyjervine, later renamed to cyclopamine.
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# Alkaloid
## Distribution in nature {#distribution_in_nature}
Alkaloids are generated by various living organisms, especially by higher plants -- about 10 to 25% of those contain alkaloids. Therefore, in the past the term \"alkaloid\" was associated with plants.
The alkaloids content in plants is usually within a few percent and is inhomogeneous over the plant tissues. Depending on the type of plants, the maximum concentration is observed in the leaves (for example, black henbane), fruits or seeds (Strychnine tree), root (*Rauvolfia serpentina*) or bark (cinchona). Furthermore, different tissues of the same plants may contain different alkaloids.
Beside plants, alkaloids are found in certain types of fungus, such as psilocybin in the fruiting bodies of the genus *Psilocybe*, and in animals, such as bufotenin in the skin of some toads and a number of insects, markedly ants. Many marine organisms also contain alkaloids. Some amines, such as adrenaline and serotonin, which play an important role in higher animals, are similar to alkaloids in their structure and biosynthesis and are sometimes called alkaloids.
## Extraction
Because of the structural diversity of alkaloids, there is no single method of their extraction from natural raw materials. Most methods exploit the property of most alkaloids to be soluble in organic solvents but not in water, and the opposite tendency of their salts.
Most plants contain several alkaloids. Their mixture is extracted first and then individual alkaloids are separated. Plants are thoroughly ground before extraction. Most alkaloids are present in the raw plants in the form of salts of organic acids. The extracted alkaloids may remain salts or change into bases. Base extraction is achieved by processing the raw material with alkaline solutions and extracting the alkaloid bases with organic solvents, such as 1,2-dichloroethane, chloroform, diethyl ether or benzene. Then, the impurities are dissolved by weak acids; this converts alkaloid bases into salts that are washed away with water. If necessary, an aqueous solution of alkaloid salts is again made alkaline and treated with an organic solvent. The process is repeated until the desired purity is achieved.
In the acidic extraction, the raw plant material is processed by a weak acidic solution (*e.g.*, acetic acid in water, ethanol, or methanol). A base is then added to convert alkaloids to basic forms that are extracted with organic solvent (if the extraction was performed with alcohol, it is removed first, and the remainder is dissolved in water). The solution is purified as described above.
Alkaloids are separated from their mixture using their different solubility in certain solvents and different reactivity with certain reagents or by distillation.
A number of alkaloids are identified from insects, among which the fire ant venom alkaloids known as solenopsins have received greater attention from researchers. These insect alkaloids can be efficiently extracted by solvent immersion of live fire ants or by centrifugation of live ants followed by silica-gel chromatography purification. Tracking and dosing the extracted solenopsin ant alkaloids has been described as possible based on their absorbance peak around 232 nanometers.
## Biosynthesis
Biological precursors of most alkaloids are amino acids, such as ornithine, lysine, phenylalanine, tyrosine, tryptophan, histidine, aspartic acid, and anthranilic acid. Nicotinic acid can be synthesized from tryptophan or aspartic acid. Ways of alkaloid biosynthesis are too numerous and cannot be easily classified. However, there are a few typical reactions involved in the biosynthesis of various classes of alkaloids, including synthesis of Schiff bases and Mannich reaction.
### Synthesis of Schiff bases {#synthesis_of_schiff_bases}
Schiff bases can be obtained by reacting amines with ketones or aldehydes. These reactions are a common method of producing C=N bonds.
In the biosynthesis of alkaloids, such reactions may take place within a molecule, such as in the synthesis of piperidine:
### Mannich reaction {#mannich_reaction}
An integral component of the Mannich reaction, in addition to an amine and a carbonyl compound, is a carbanion, which plays the role of the nucleophile in the nucleophilic addition to the ion formed by the reaction of the amine and the carbonyl.
The Mannich reaction can proceed both intermolecularly and intramolecularly:
## Dimer alkaloids {#dimer_alkaloids}
In addition to the described above monomeric alkaloids, there are also dimeric, and even trimeric and tetrameric alkaloids formed upon condensation of two, three, and four monomeric alkaloids. Dimeric alkaloids are usually formed from monomers of the same type through the following mechanisms:
- Mannich reaction, resulting in, *e.g.*, voacamine
- Michael reaction (villalstonine)
- Condensation of aldehydes with amines (toxiferine)
- Oxidative addition of phenols (dauricine, tubocurarine)
- Lactonization (carpaine).
<File:Voacamine> chemical structure.png\|Voacamine <File:Villalstonine.svg>\|Villalstonine <File:Toxiferine> I.png\|Toxiferine <File:Dauricine.svg>\|Dauricine <File:Tubocurarine.svg>\|Tubocurarine <File:Carpaine.png>\|Carpaine
There are also dimeric alkaloids formed from two distinct monomers, such as the *vinca* alkaloids vinblastine and vincristine, which are formed from the coupling of catharanthine and vindoline. The newer semi-synthetic chemotherapeutic agent vinorelbine is used in the treatment of non-small-cell lung cancer. It is another derivative dimer of vindoline and catharanthine and is synthesised from anhydrovinblastine, starting either from leurosine or the monomers themselves.
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# Alkaloid
## Biological role {#biological_role}
Alkaloids are among the most important and best-known secondary metabolites, i.e. biogenic substances not directly involved in the normal growth, development, or reproduction of the organism. Instead, they generally mediate ecological interactions, which may produce a selective advantage for the organism by increasing its survivability or fecundity. In some cases their function, if any, remains unclear. An early hypothesis, that alkaloids are the final products of nitrogen metabolism in plants, as urea and uric acid are in mammals, was refuted by the finding that their concentration fluctuates rather than steadily increasing.
Most of the known functions of alkaloids are related to protection. For example, aporphine alkaloid liriodenine produced by the tulip tree protects it from parasitic mushrooms. In addition, the presence of alkaloids in the plant prevents insects and chordate animals from eating it. However, some animals are adapted to alkaloids and even use them in their own metabolism. Such alkaloid-related substances as serotonin, dopamine and histamine are important neurotransmitters in animals. Alkaloids are also known to regulate plant growth. One example of an organism that uses alkaloids for protection is the *Utetheisa ornatrix*, more commonly known as the ornate moth. Pyrrolizidine alkaloids render these larvae and adult moths unpalatable to many of their natural enemies like coccinelid beetles, green lacewings, insectivorous hemiptera and insectivorous bats. Another example of alkaloids being utilized occurs in the poison hemlock moth (*Agonopterix alstroemeriana).* This moth feeds on its highly toxic and alkaloid-rich host plant poison hemlock (*Conium maculatum*) during its larval stage. *A. alstroemeriana* may benefit twofold from the toxicity of the naturally-occurring alkaloids, both through the unpalatability of the species to predators and through the ability of *A. alstroemeriana* to recognize *Conium maculatum* as the correct location for oviposition. A fire ant venom alkaloid known as solenopsin has been demonstrated to protect queens of invasive fire ants during the foundation of new nests, thus playing a central role in the spread of this pest ant species around the world.
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# Alkaloid
## Applications
### In medicine {#in_medicine}
Medical use of alkaloid-containing plants has a long history, and, thus, when the first alkaloids were isolated in the 19th century, they immediately found application in clinical practice. Many alkaloids are still used in medicine, usually in the form of salts widely used including the following:
Alkaloid Action
-------------------------- -----------------------------------------------------
Ajmaline Antiarrhythmic
Emetine Antiprotozoal agent, emesis
Ergot alkaloids Vasoconstriction, hallucinogenic, Uterotonic
Glaucine Antitussive
Morphine Analgesic
Nicotine Stimulant, nicotinic acetylcholine receptor agonist
Physostigmine Inhibitor of acetylcholinesterase
Quinidine Antiarrhythmic
Quinine Antipyretic, antimalarial
Reserpine Antihypertensive
Tubocurarine Muscle relaxant
Vinblastine, vincristine Antitumor
Vincamine Vasodilating, antihypertensive
Yohimbine Stimulant, aphrodisiac
Berberine Antihyperglycaemic
Many synthetic and semisynthetic drugs are structural modifications of the alkaloids, which were designed to enhance or change the primary effect of the drug and reduce unwanted side-effects. For example, naloxone, an opioid receptor antagonist, is a derivative of thebaine that is present in opium.
<File:Thebaine> skeletal.svg\|Thebaine <File:Naloxone.svg>\|Naloxone
### In agriculture {#in_agriculture}
Prior to the development of a wide range of relatively low-toxic synthetic pesticides, some alkaloids, such as salts of nicotine and anabasine, were used as insecticides. Their use was limited by their high toxicity to humans.
### Use as psychoactive drugs {#use_as_psychoactive_drugs}
Preparations of plants and fungi containing alkaloids and their extracts, and later pure alkaloids, have long been used as psychoactive substances. Cocaine, caffeine, and cathinone are stimulants of the central nervous system. Mescaline and many indole alkaloids (such as psilocybin, dimethyltryptamine and ibogaine) have hallucinogenic effect. Morphine and codeine are strong narcotic pain killers.
There are alkaloids that do not have strong psychoactive effect themselves, but are precursors for semi-synthetic psychoactive drugs. For example, ephedrine and pseudoephedrine are used to produce methcathinone and methamphetamine. Thebaine is used in the synthesis of many painkillers such as oxycodone
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# Albion, Michigan
**Albion** is a city in Calhoun County in the south central region of the Lower Peninsula of the U.S. state of Michigan. The population was 7,700 at the 2020 census. Albion is part of the Battle Creek Metropolitan Statistical Area.
The earliest English-speaking settlers also called this area *The Forks*, because it is at the confluence of the north and south branches of the Kalamazoo River. In the early 20th century, immigrants came to Albion from various eastern European nations, including the current Lithuania and Russia. More recently, Latino immigrants have come from Mexico and Central America. The *Festival of the Forks* has been held annually since 1967 to celebrate Albion\'s diverse ethnic heritage.
Since the 19th century, several major manufacturers were established in Albion, which became known as a factory town. This changed after several manufacturers closed. In the 21st century, Albion\'s culture is changing to that of a college town whose residents have a strong interest in technology and sustainability. Albion College is a private liberal arts college with a student population of about 1,250. Albion is a sister city with Noisy-le-Roi, France.
## History
The first European-American settler, Tenney Peabody, arrived in 1833 along with his brother-in-law, Charles Blanchard, and another young man, Clark Dowling. Peabody\'s family followed soon after. In 1835, the Albion Company, a land development company formed by Jesse Crowell, platted a village. Peabody\'s wife was asked to name the settlement. She considered the name \"Peabodyville\", but selected \"Albion\" instead, after the former residence of Jesse Crowell. Crowell was appointed in 1838 as the first US postmaster there.
Many early settlers migrated to Albion from western New York and New England, part of a movement after the construction of the Erie Canal and the opening of new lands in Michigan and other Great Lakes territories. They first developed agriculture and it became a rural trading village. Settlers were strong supporters of education and in 1835, Methodists established Albion College affiliated with their church. Its first classes were held in 1843. The college was known by a few other names before 1861. At that time it was fully authorized to confer four-year degrees on both men and women.
Albion incorporated as a village in 1855, following construction of the railroad here in 1852, which stimulated development. It became a city in 1885.
Mills were constructed to operate on the water power of the forks of the Kalamazoo River. They were the first industry in the town, used to process lumber, grain, and other products to build the village. Albion quickly became a mill town as well as an agricultural market. The river that powered industry also flooded the town.
In the Great Flood of 1908, there was severe property damage. In February, several feet of snow fell across the region. Heavy rains and warmer conditions in early March created water saturation in the ground and risk of flooding because of the rivers\' high flow. After the Homer Dam broke around 3 p.m. on March 7, the Kalamazoo River flooded Albion. By midnight, the bridges surrounding town were underwater. Six buildings in Albion collapsed, resulting in more than \$125,000 in damage (1908 dollars). The town struggled to recover.
In the late 19th and early 20th centuries, numerous Lithuanian and other Eastern European immigrants settled there, most working for the Albion Malleable Iron Company, and some in the coal mine north of town. The iron company initially made agricultural implements, but around World War I shifted to making automotive parts. The Malleable merged in 1969 with the Hayes Corporation, becoming the Hayes-Albion Corporation. Now known as a division of Harvard Industries, the company continues to produce automotive castings in Albion. Molder Statue Park downtown is dedicated to the many molders who dealt with molten iron.
There were soon enough Lithuanians in town to establish Holy Ascension Orthodox Church, which they built in 1916. It is part of the Orthodox Church in America. Today its services are in English.
Albion\'s population peaked in 1960. In 1973 Albion was named an All-America City by the National Civic League. It celebrated the award on May 15, 1974, when Michigan Governor William Milliken and many other dignitaries came to town. In 1975 the closure of a major factory began a difficult period of industrial restructuring and decline in jobs and population.
Since that time citizens have mobilized, founding the Albion Community Foundation in 1968. They formed the Albion Volunteer Service Organization in the 1980s, with support from Albion College, to address the challenge of diminishing economic opportunity.
Key to the City Honor Bestowed:
- 1964: Aunt Jemima visited Albion on January 25.
- 1960s: Columnist Ann Landers was presented with a key upon her visit to Starr Commonwealth for Boys.
## Law and government {#law_and_government}
Albion has a council-manager government. City residents elect a mayor at-large and City Council members from each of six single-member districts. The council in turn selects a city manager to handle the city\'s day-to-day affairs. The mayor presides over and is a voting member of the council. Council members are elected to four-year terms, staggered every two years. A mayor is elected every two years. The city levies an income tax of 1% on residents and 0.5% on nonresidents.
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# Albion, Michigan
## Geography
According to the United States Census Bureau, the city has an area of 4.51 sqmi, of which 4.41 sqmi is land and 0.10 sqmi is water. Albion is 42.24 degrees north of the equator and 84.75 degrees west of the prime meridian.
## Climate
## Demographics
### 2010 population by gender/age {#population_by_genderage}
----------------- ------- -------
**Male** 4,013 46.6%
**Female** 4,603 53.4%
**Under 18** 1,872 21.7%
**18 and over** 6,744 78.3%
**20-24** 1,364 15.8%
**25-34** 842 9.8%
**35-49** 1,251 14.5%
**50-64** 1,368 15.9%
**65+** 1,124 13.0%
----------------- ------- -------
### 2010 population by ethnicity {#population_by_ethnicity}
---------------------------- ------- -------
**Hispanic or Latino** 500 5.8%
**Non Hispanic or Latino** 8,116 94.2%
---------------------------- ------- -------
### 2010 population by race {#population_by_race}
------------------------------------------------ ------- -------
**White** 5,477 63.6%
**African American** 2,579 29.9%
**Asian** 91 1.1%
**American Indian and Alaska Native** 29 0.3%
**Native Hawaiian and Other Pacific Islander** 17 0.2%
**Other** 90 1.0%
**Identified by two or more** 333 3.9%
------------------------------------------------ ------- -------
## Transportation
### Major highways {#major_highways}
-
-
-
-
### Rail
Amtrak provides daily service to Albion, operating its Wolverine both directions between Chicago, Illinois and Pontiac, Michigan, via Detroit.
### Bus
Greyhound Lines provides daily intercity city bus service to Albion between Chicago and Detroit.
## Notable people {#notable_people}
- Kim Cascone, musician, composer, owner of Silent Records; born in Albion
- M. F. K. Fisher, food writer, born in Albion
- Ada Iddings Gale, author, lived and buried in Albion
- Helen Rose Hull, author and university professor, was born in Albion. Her 1932 book *Heat Lightning* concerns a family that owns agricultural implement and automotive parts factories in a small town during the 1930s.
- Frank Joranko, football player and coach for Albion College
- LaVall Jordan, head men\'s basketball coach for Butler University, born in Albion
- Martin Wells Knapp, American Methodist evangelist who founded the Pilgrim Holiness Church and God\'s Bible School and College, born in Albion.
- Bill Laswell, jazz bassist, record producer and record label owner; raised in Albion
- Jerome D
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# Alessandro Scarlatti
**Pietro Alessandro Gaspare Scarlatti** (2 May 1660 -- 22 October 1725) was an Italian Baroque composer, known especially for his operas and chamber cantatas. He is considered the most important representative of the Neapolitan school of opera.
Nicknamed by his contemporaries \"the Italian Orpheus\", he divided his career between Naples and Rome; a significant part of his works was composed for the papal city. He is often considered the founder of the Neapolitan school, although he has only been its most illustrious representative: his contribution, his originality and his influence were essential, as well as lasting, both in Italy and in Europe.
Particularly known for his operas, he brought the Italian dramatic tradition to its maximum development, begun by Monteverdi at the beginning of 17th century and continued by Cesti, Cavalli, Carissimi, Legrenzi and Stradella, designing the final form of the *Da capo aria*, imitated throughout Europe. He was also the inventor of the Italian overture in three movements (which was of the highest importance in the development of the symphony), of the four-part sonata (progenitor of the modern string quartet), and of the technique of motivic development. He was a model for the musical theater of his time, as evoked by Händel\'s Italian works, deeply influenced by his theatrical music. Eclectic, Scarlatti also worked on all the other common genres of his time, from the sonata to the concerto grosso, from the motet to the mass, from the oratorio to the cantata, the latter being a genre in which he was an undisputed master.
He was the father of two other composers, Domenico Scarlatti and Pietro Filippo Scarlatti.
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# Alessandro Scarlatti
## Life
Scarlatti was born in Palermo (or in Trapani), then part of the Kingdom of Sicily. He received his first musical education in his family in Palermo. He is generally said to have been a pupil of Giacomo Carissimi in Rome, and some theorize that he had some connection with northern Italy because his early works seem to show the influence of Stradella and Legrenzi. The production at Rome of his opera *Gli equivoci nel sembiante* (1679) gained him the support of Queen Christina of Sweden (who at the time was living in Rome), and he became her *maestro di cappella*. In February 1684 he became *maestro di cappella* to the viceroy of Naples, perhaps through the influence of his sister, an opera singer, who might have been the mistress of an influential Neapolitan noble. Here he produced a long series of operas, remarkable chiefly for their fluency and expressiveness, as well as other music for state occasions.
In 1702 Scarlatti left Naples and did not return until the Spanish domination had been superseded by that of the Austrians. In the interval he enjoyed the patronage of Ferdinando de\' Medici, for whose private theatre near Florence he composed operas, and of Cardinal Ottoboni, who made him his *maestro di cappella*, and procured him a similar post at the Basilica di Santa Maria Maggiore in Rome in 1703.
After visiting Venice and Urbino in 1707, Scarlatti took up his duties in Naples again in 1708, and remained there until 1717. By this time Naples seems to have become tired of his music; the Romans, however, appreciated it better, and it was at the Teatro Capranica in Rome that he produced some of his finest operas (*Telemaco*, 1718; *Marco Attilio Regolò*, 1719; *La Griselda*, 1721), as well as some noble specimens of church music, including a *Messa di Santa Cecilia* for chorus and orchestra, composed in honor of Saint Cecilia for Cardinal Francesco Acquaviva in 1721. His last work on a large scale appears to have been the unfinished *Erminia* serenata for the marriage of the prince of Stigliano in 1723. He died in Naples in 1725 and is entombed there at the church of Santa Maria di Montesanto.
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# Alessandro Scarlatti
## Music
Scarlatti\'s music forms an important link between the early Baroque Italian vocal styles of the 17th century, with their centers in Florence, Venice and Rome, and the classical school of the 18th century. Scarlatti\'s style, however, is more than a transitional element in Western music; like most of his Naples colleagues he shows an almost modern understanding of the psychology of modulation and also frequently makes use of the ever-changing phrase lengths so typical of the Napoli school.
His early operas---*Gli equivoci nel sembiante* 1679; *L\'honestà negli amori* 1680, containing the famous aria \"Già il sole dal Gange\"; *Il Pompeo* 1683, containing the well-known airs \"O cessate di piagarmi\" and \"Toglietemi la vita ancor,\" and others down to about 1685---retain the older cadences in their recitatives, and a considerable variety of neatly constructed forms in their charming little arias, accompanied sometimes by the string quartet, treated with careful elaboration, sometimes with the continuo alone. By 1686, he had definitely established the \"Italian overture\" form (second edition of *Dal male il bene*), and had abandoned the ground bass and the binary form air in two stanzas in favour of the ternary form or da capo type of air. His best operas of this period are *La Rosaura* (1690, printed by the Gesellschaft für Musikforschung), and *Pirro e Demetrio* (1694), in which occur the arias \"Le Violette\", and \"Ben ti sta, traditor\".
From about 1697 onwards (*La caduta del Decemviri*), influenced partly perhaps by the style of Giovanni Bononcini and probably more by the taste of the viceregal court, his opera arias become more conventional and commonplace in rhythm, while his scoring is hasty and crude, yet not without brilliance (*L\'Eraclea*, 1700), the oboes and trumpets being frequently used, and the violins often playing in unison. The operas composed for Ferdinando de\' Medici are lost; they might have given a more favourable idea of his style as his correspondence with the prince shows that they were composed with a very sincere sense of inspiration.
*Mitridate Eupatore*, accounted his masterpiece, composed for Venice in 1707, contains music far in advance of anything that Scarlatti had written for Naples, both in technique and in intellectual power. The later Neapolitan operas (*L\'amor volubile e tiranno* 1709; *La principessa fedele* 1710; *Tigrane*, 1714, &c.) are showy and effective rather than profoundly emotional; the instrumentation marks a great advance on previous work, since the main duty of accompanying the voice is thrown upon the string quartet, the harpsichord being reserved exclusively for the noisy instrumental *ritornelli*. In his opera *Teodora* (1697) he originated the use of the orchestral *ritornello*.
His last group of operas, composed for Rome, exhibit a deeper poetic feeling, a broad and dignified style of melody, a strong dramatic sense, especially in accompanied recitatives, a device which he himself had been the first to use as early as 1686 (*Olimpia vendicata*) and a much more modern style of orchestration, the horns appearing for the first time, and being treated with striking effect.
Besides the operas, oratorios (*Agar et Ismaele esiliati*, 1684; *La Maddalena*, 1685; *La Giuditta*, 1693; *Humanita e Lucifero*, 1704; *Christmas Oratorio*, c. 1705; *Cain*, 1707; *S. Filippo Neri*, 1714; and others) and serenatas, which all exhibit a similar style, Scarlatti composed upwards of five hundred chamber-cantatas for solo voice. These represent the most intellectual type of chamber-music of their period, and it is to be regretted that they have remained almost entirely in manuscript, since a careful study of them is indispensable to anyone who wishes to form an adequate idea of Scarlatti\'s development.
His few remaining Masses and church music in general are comparatively unimportant, except the great *Saint Cecilia Mass* (1721), which is one of the first attempts at the style which reached its height in the great Masses of Johann Sebastian Bach and Ludwig van Beethoven. His instrumental music, though not without interest, is curiously antiquated as compared with his vocal works.
## Operas
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# Alessandro Scarlatti
## Recordings
- Philharmonia Baroque Orchestra, Nicholas McGegan. (2016). *La Gloria di Primavera*. Philharmonia Baroque Orchestra. Diana Moore, Suzana Ograjensek, Nicholas Phan, Clint van der Linde, Douglas Williams, Philharmonia Chorale.
- Akademie für alte Musik Berlin, René Jacobs. (2007). *Griselda*. Harmonia Mundi HMC 901805.07. Dorothea Röschmann, Lawrence Zazzo, Veronica Cangemi, Bernarda Fink, Silvia Tro Santafé, Kobie van Rensburg.
- Le Consert de l\'Hostel Dieu. (2006). *Il martirio di Sant\'Orsola*. Ligia digital: 0202176--07
- Le parlement de musique. (2005). *La Giuditta*. Ambronay editions: AMY004
- Ensemble Europa Galante. (2004). *Oratorio per la Santissima Trinità*. Virgin Classics: 5 45666 2
- Academia Bizantina. (2004). *Il Giardino di Rose*. Decca: 470 650-2 DSA.
- Orqestra barocca di Sevilla . (2003). *Colpa, Pentimento e Grazia*. Harmonia Mundi: HMI 987045.46
- Seattle Baroque. (2001). *Agar et Ismaele Esiliati*. Centaur: CRC 2664
- *Sedecia, re di Gerusalemme*. 2000 . Gérard Lesne, Philippe Jaroussky, Virginie Pouchon, Mark Padmore, Peter Harvey, Il Seminario musicale. Virgin veritas, Erato
- Capella Palatina. (2000). *Davidis pugna et victoria*. Agora: AG 249.1
- Akademie für alte Musik Berlin, René Jacobs. (1998). *Il Primo Omicidio*. Harmonia Mundi Fr. Dorothea Röschmann, Graciela Oddone, Richard Croft, René Jacobs, Bernarda Fink, Antonio Abete
- Ensemble Europa Galante. (1995). *Humanita e Lucifero*. Opus 111: OPS 30--129
- Ensemble Europa Galante. (1993). *La Maddalena*. Opus 111: OPS 30--96
- Allesandro Stradella Consort. (1992). Cantata natalizia *Abramo, il tuo sembiante*. Nuova era: 7117
- I Musici. (1991). *Concerto Grosso*. Philips Classics Productions: 434 160--2
- I Musici. William Bennett (Flute), Lenore Smith (Flute), Bernard Soustrot (Trumpet), Hans Elhorst (Oboe). (1961). *12 Sinfonie di concerto grosso* Philips Box 6769 066 \[9500 959 & 9500 960 -- 2 vinyl discs\]
- Emma Kirkby, soprano and Daniel Taylor, countertenor, with the Theatre of Early Music. (2005). *Stabat Mater*. ATMA Classique: ACD2 2237
- Francis Colpron, recorder, with Les Boréades. (2007). *Concertos for flute*. ATMA Classique: ACD2 2521
- Nederlands Kamerkoor, with Harry van der Kamp, conductor. (2008). *Vespro della Beata Vergine* for 5 voices and continuo
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# ALF Tales
***ALF Tales*** is a 30-minute Saturday morning animated series that aired on NBC from September 10, 1988, to December 9, 1989. The show is a spin-off of *ALF: The Animated Series* that featured characters from that series playing various characters from fairy tales. The fairy tale parody was usually altered for comedic effect in a manner akin to Jay Ward\'s \"Fractured Fairy Tales\".
The episodes were performed in the style of a resident theater company or ensemble cast where Gordon and Rhonda would take the leading male and female roles, and the other characters were cast according to their characteristics.
Many stories spoof a film genre, such as the \"Cinderella\" episode which is presented like an Elvis Presley film. Some episodes featured a \"fourth wall\" effect where Gordon is backstage preparing for the episode, and Rob Cowan would appear drawn as a TV executive (who introduced himself as \"Roger Cowan, network executive\") who tries to brief Gordon on how to improve the episode. For instance Cowan once told Gordon who was readying for a medieval themed episode that \"less than 2% of our audience lives in the Dark Ages\".
## Voice cast {#voice_cast}
- Paul Fusco as ALF (Gordon Shumway), Rick Fusterman
- Paulina Gillis) as Augie, Rhonda
- Peggy Mahon as Flo
- Thick Wilson as Larson Petty, Bob
- Dan Hennessey as Sloop
- Rob Cowan as Skip
- Ellen-Ray Hennessy as Stella the Waitress
- Noam Zylberman as Curtis (1988)
- Michael Fantini as Curtis (1989)
## Episodes
### Season 1 (1988--89) {#season_1_198889}
### Season 2 (1989) {#season_2_1989}
## Home media {#home_media}
The first seven episodes were released on DVD on May 30, 2006, in Region 1 from Lionsgate Home Entertainment in a single-disc release entitled *ALF and The Beanstalk and Other Classic Fairy Tales*.
The complete series was remastered and subsequently released on October 17, 2023, by Shout! Factory in the DVD box set *ALF: The Complete Series (Deluxe Edition)*. The box set release also included the original 1986--90 sitcom, *ALF: The Animated Series* and *Project: ALF*
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# Accelerated Graphics Port
**Accelerated Graphics Port** (**AGP**) is a parallel expansion card standard, designed for attaching a video card to a computer system to assist in the acceleration of 3D computer graphics. It was originally designed as a successor to PCI-type connections for video cards. Since 2004, AGP was progressively phased out in favor of PCI Express (PCIe), which is serial, as opposed to parallel; by mid-2008, PCI Express cards dominated the market and only a few AGP models were available, with GPU manufacturers and add-in board partners eventually dropping support for the interface in favor of PCI Express.
## `{{Anchor|APERTURE}}`{=mediawiki}Advantages over PCI {#advantages_over_pci}
AGP is a superset of the PCI standard, designed to overcome PCI\'s limitations in serving the requirements of the era\'s high-performance graphics cards.
The primary advantage of AGP is that it doesn\'t share the PCI bus, providing a dedicated, point-to-point pathway between the expansion slot(s) and the motherboard chipset. The direct connection also allows higher clock speeds.
The second major change is the use of split transactions, wherein the address and data phases are separated. The card may send many address phases, so the host can process them in order, avoiding any long delays caused by the bus being idle during read operations.
Third, PCI bus handshaking is simplified. Unlike PCI bus transactions, whose length is negotiated on a cycle-by-cycle basis using the FRAME# and STOP# signals, AGP transfers are always a multiple of 8 bytes long, with the total length included in the request. Further, rather than using the IRDY# and TRDY# signals for each word, data is transferred in blocks of 4 clock cycles (32 words at AGP 8× speed), and pauses are allowed only between blocks.
Finally, AGP allows (mandatory only in AGP 3.0) *sideband addressing*, meaning that the address and data buses are separated, so the address phase does not use the main address/data (AD) lines at all. This is done by adding an extra 8-bit \"SideBand Address\" bus, over which the graphics controller can issue new AGP requests while other AGP data is flowing over the main 32 address/data (AD) lines. This results in improved overall AGP data throughput.
This great improvement in memory read performance makes it practical for an AGP card to read textures directly from system RAM, while a PCI graphics card must copy it from system RAM to the card\'s video memory. System memory is made available using the graphics address remapping table (GART), which apportions main memory as needed for texture storage. The maximum amount of system memory available to AGP is defined as the *AGP aperture*.
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# Accelerated Graphics Port
## History
The AGP slot first appeared on x86-compatible system boards based on Socket 7 Intel P5 Pentium and Slot 1 P6 Pentium II processors. Intel introduced AGP support with the i440LX Slot 1 chipset on August 26, 1997, and a flood of products followed from all the major system board vendors.
The first Socket 7 chipsets to support AGP were the VIA Apollo VP3, SiS 5591/5592, and the ALI Aladdin V. Intel never released an AGP-equipped Socket 7 chipset. FIC demonstrated the first Socket 7 AGP system board in November 1997 as the *FIC PA-2012* based on the VIA Apollo VP3 chipset, followed very quickly by the *EPoX P55-VP3* also based on the VIA VP3 chipset which was first to market.
Early video chipsets featuring AGP support included the Rendition Vérité V2200, 3dfx Voodoo Banshee, Nvidia RIVA 128, 3Dlabs PERMEDIA 2, Intel i740, ATI Rage series, Matrox Millennium II, and S3 ViRGE GX/2. Some early AGP boards used graphics processors built around PCI and were simply bridged to AGP. This resulted in the cards benefiting little from the new bus, with the only improvement used being the 66 MHz bus clock, with its resulting doubled bandwidth over PCI, and bus exclusivity. Intel\'s i740 was explicitly designed to exploit the new AGP feature set; in fact it was designed to texture only from AGP memory, making PCI versions of the board difficult to implement (local board RAM had to emulate AGP memory), though this was eventually accomplished much later in the form of AGP-to-PCI bridges.
Microsoft first introduced AGP support into Windows via the USB Supplement patch for OSR2 of Windows 95 in 1997, also known as OSR2.1. The first Windows NT-based operating system to receive AGP support was Windows NT 4.0 with Service Pack 3, also in 1997. Linux support for AGP-enhanced fast data transfers was first added in 1999 with the implementation of the AGPgart kernel module.
### Later use {#later_use}
With the increasing adoption of PCIe, graphics cards manufacturers continued to produce AGP cards as the standard became obsolete. As GPUs began to be designed to connect to PCIe, an additional PCIe-to-AGP bridge-chip was required to create an AGP-compatible graphics card. The inclusion of a bridge, and the need for a separate AGP card design, incurred additional board costs.
The GeForce 6600 and ATI Radeon X800 XL, released during 2004--2005, were the first bridged cards. In 2009 AGP cards from Nvidia had a ceiling of the GeForce 7 series. In 2011 DirectX 10-capable AGP cards from AMD vendors (Club 3D, HIS, Sapphire, Jaton, Visiontek, Diamond, etc.) included the Radeon HD 2400, 3450, 3650, 3850, 4350, 4650, and 4670. The HD 5000 AGP series mentioned in the AMD Catalyst software was never available. There were many problems with the AMD Catalyst 11.2 - 11.6 AGP hotfix drivers under Windows 7 with the HD 4000 series AGP video cards; use of 10.12 or 11.1 AGP hotfix drivers is a possible workaround. Several of the vendors listed above make available past versions of the AGP drivers.
By 2010, no new motherboard chipsets supported AGP and few new motherboards had AGP slots, however some continued to be produced with older AGP-supporting chipsets.
In 2016, Windows 10 version 1607 dropped support for AGP.`{{Unreliable source?|date=November 2022}}`{=mediawiki} Possible future removal of support for AGP from open-source Linux kernel drivers was considered in 2020.`{{update inline|date=January 2024}}`{=mediawiki}
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# Accelerated Graphics Port
## Versions
+---------------+---------+-----------+-------+-------------+-------------+
| Specification | Voltage | Clock | Speed | Transfers/\ | Rate (MB/s) |
| | | | | clock | |
+===============+=========+===========+=======+=============+=============+
| PCI | 3.3/5 V | 33 MHz | --- | 1 | 133 |
+---------------+---------+-----------+-------+-------------+-------------+
| PCI 2.1 | 3.3/5 V | 33/66 MHz | --- | 1 | 133/266 |
+---------------+---------+-----------+-------+-------------+-------------+
| AGP 1.0 | 3.3 V | 66 MHz | 1× | 1 | 266 |
+---------------+---------+-----------+-------+-------------+-------------+
| AGP 1.0 | 3.3 V | 66 MHz | 2× | 2 | 533 |
+---------------+---------+-----------+-------+-------------+-------------+
| AGP 2.0 | 1.5 V | 66 MHz | 4× | 4 | 1066 |
+---------------+---------+-----------+-------+-------------+-------------+
| AGP 3.0 | 0.8 V | 66 MHz | 8× | 8 | 2133 |
+---------------+---------+-----------+-------+-------------+-------------+
| AGP 3.5^\*^ | 0.8 V | 66 MHz | 8× | 8 | 2133 |
+---------------+---------+-----------+-------+-------------+-------------+
: AGP and PCI: 32-bit buses operating at 66 and 33 MHz respectively
Intel released \"AGP specification 1.0\" in 1997. It specified 3.3 V signals and 1× and 2× speeds. Specification 2.0 documented 1.5 V signaling, which could be used at 1×, 2× and the additional 4× speed and 3.0 added 0.8 V signaling, which could be operated at 4× and 8× speeds. (1× and 2× speeds are physically possible, but were not specified.)
Available versions are listed in the adjacent table.
AGP version 3.5 is only publicly mentioned by Microsoft under *Universal Accelerated Graphics Port (UAGP)*, which specifies mandatory supports of extra registers once marked optional under AGP 3.0. Upgraded registers include PCISTS, CAPPTR, NCAPID, AGPSTAT, AGPCMD, NISTAT, NICMD. New required registers include APBASELO, APBASEHI, AGPCTRL, APSIZE, NEPG, GARTLO, GARTHI.
There are various physical interfaces (connectors); see the Compatibility section.
### Official extensions {#official_extensions}
#### AGP Pro {#agp_pro}
An official extension for cards that required more electrical power, with a longer slot with additional pins for that purpose. AGP Pro cards were usually workstation-class cards used to accelerate professional computer-aided design applications employed in the fields of architecture, machining, engineering, simulations, and similar fields.
#### 64-bit AGP {#bit_agp}
A 64-bit channel was once proposed as an optional standard for AGP 3.0 in draft documents, but it was dropped in the final version of the standard.
The standard allows 64-bit transfer for AGP8× reads, writes, and fast writes; 32-bit transfer for PCI operations.
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# Accelerated Graphics Port
## Versions
### Unofficial variations {#unofficial_variations}
A number of non-standard variations of the AGP interface have been produced by manufacturers.
#### Internal AGP interface {#internal_agp_interface}
Ultra-AGP, Ultra-AGPII: It is an internal AGP interface standard used by SiS for the north bridge controllers with integrated graphics. The original version supports same bandwidth as AGP 8×, while Ultra-AGPII has maximum 3.2 GB/s bandwidth.
#### PCI-based AGP ports {#pci_based_agp_ports}
AGP Express: Not a true AGP interface, but allows an AGP card to be connected over the legacy PCI bus on a PCI Express motherboard. It is a technology used on motherboards made by ECS, intended to allow an existing AGP card to be used in a new motherboard instead of requiring a PCIe card to be obtained (since the introduction of PCIe graphics cards few motherboards provide AGP slots). An \"AGP Express\" slot is basically a PCI slot (with twice the electrical power) with an AGP connector. It offers backward compatibility with AGP cards, but provides incomplete support (some AGP cards do not work with AGP Express) and reduced performance---the card is forced to use the shared PCI bus at its lower bandwidth, rather than having exclusive use of the faster AGP.\
AGI: The ASRock Graphics Interface (AGI) is a proprietary variant of the Accelerated Graphics Port (AGP) standard. Its purpose is to provide AGP-support for ASRock motherboards that use chipsets lacking native AGP support. However, it is not fully compatible with AGP, and several video card chipsets are known not to be supported.\
AGX: The EPoX Advanced Graphics eXtended (AGX) is another proprietary AGP variant with the same advantages and disadvantages as AGI. User manuals recommend not using AGP 8× ATI cards with AGX slots.\
XGP: The Biostar Xtreme Graphics Port is another AGP variant, also with the same advantages and disadvantages as AGI and AGX.
#### PCIe based AGP ports {#pcie_based_agp_ports}
AGR: The Advanced Graphics Riser is a variation of the AGP port used in some PCIe motherboards made by MSI to offer limited backward compatibility with AGP. It is, effectively, a modified PCIe slot allowing for performance comparable to an AGP 4×/8× slot, but does not support all AGP cards; the manufacturer published a list of some cards and chipsets that work with the modified slot.
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# Accelerated Graphics Port
## Compatibility
AGP cards are backward and forward compatible within limits. 1.5 V-only keyed cards will not go into 3.3 V slots and vice versa, though \"Universal\" cards exist which will fit into either type of slot. There are also unkeyed \"Universal\" slots that will accept either type of card. When an AGP Universal card is plugged-into an AGP Universal slot, only the 1.5 V portion of the card is used. Some cards, like Nvidia\'s GeForce 6 series (except the 6200) or ATI\'s Radeon X800 series, only have keys for 1.5 V to prevent them from being installed in older mainboards without 1.5 V support. Some of the last modern cards with 3.3 V support were:
- the Nvidia GeForce FX series (FX 5200, FX 5500, FX 5700, some FX 5800, FX 5900 and some FX 5950),
- certain Nvidia GeForce 6 series and 7 series (some 6600, 6800, 7300, 7600, 7800, 7900 and 7950 cards, really uncommon compared to their AGP 1.5v only versions; the GeForce 6200 is the only exception, as it was the most common card with 3.3 V support),
- the ATI Radeon 9000 series (Radeon 9500/9700/9800 (R300/R350), but not 9600/9800 (R360/RV360)).
Some cards incorrectly have dual notches, and some motherboards incorrectly have fully open slots, allowing a card to be plugged into a slot that does not support the correct signaling voltage, which may damage card or motherboard. Some incorrectly designed older 3.3 V cards have the 1.5 V key.
AGP Pro cards will not fit into standard slots, but standard AGP cards will work in a Pro slot. Motherboards equipped with a Universal AGP Pro slot will accept a 1.5 V or 3.3 V card in either the AGP Pro or standard AGP configuration, a Universal AGP card, or a Universal AGP Pro card.
There are some proprietary systems incompatible with standard AGP; for example, Apple Power Macintosh computers with the Apple Display Connector (ADC) have an extra connector which delivers power to the attached display. Some cards designed to work with a specific CPU architecture (e.g., PC, Apple) may not work with others due to firmware issues.
Mark Allen of Playtools.com has made the following comments regarding practical AGP compatibility for AGP 3.0 and AGP 2.0: `{{blockquote|... nobody makes AGP 3.0 cards, and nobody makes AGP 3.0 motherboards. At least not any manufacturers I can find. Every single video card I could find which claimed to be an AGP 3.0 card was actually a universal 1.5V AGP 3.0 card. And every motherboard which claimed to be an AGP 3.0 motherboard turned out to be a universal 1.5V AGP 3.0 motherboard. It makes sense, if you think about it, because if anyone actually shipped a consumer-oriented product which supported only 0.8 volts, they would end up with lots of confused customers and a support nightmare. In the consumer market, you'd have to be crazy to ship a 0.8 volt only product.<ref>{{cite web|last1=Allen|first1=Mark|title=AGP compatibility for sticklers|work=Video card information|url=http://www.playtool.com/pages/agpcompat/agp.html|publisher=PlayTool.com|archive-url=https://web.archive.org/web/20160622083724/http://www.playtool.com/pages/agpcompat/agp.html|archive-date=22 June 2016|year=2006}}</ref>}}`{=mediawiki}
## Power consumption {#power_consumption}
Slot Type 3.3 V 5 V 12 V 3.3 V Aux 1.5 V 3.3 V 12 V Total power
------------ ------- ----- ------ ----------- ------- ------- -------- -------------
AGP 6 A 2 A 1 A 0.375 mA 2 A \- \- 48.25 W
AGP Pro110 7.6 A 9.2 A 50 to 110 W
AGP Pro50 7.6 A 4.17 A 25 to 50 W
: AGP power provisioning
Actual power supplied by an AGP slot depends upon the card used. The maximum current drawn from the various rails is given in the specifications for the various versions. For example, if maximum current is drawn from all supplies and all voltages are at their specified upper limits, an AGP 3.0 slot can supply up to 48.25 watts; this figure can be used to specify a power supply conservatively, but in practice a card is unlikely ever to draw more than 40 W from the slot, with many using less. AGP Pro provides additional power up to 110 W. Many AGP cards had additional power connectors to supply them with more power than the slot could provide.
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# Accelerated Graphics Port
## Protocol
An AGP bus is a superset of a 66 MHz conventional PCI bus and, immediately after reset, follows the same protocol. The card must act as a PCI target, and optionally may act as a PCI master. (AGP 2.0 added a \"fast writes\" extension which allows PCI writes from the motherboard to the card to transfer data at higher speed.)
After the card is initialized using PCI transactions, AGP transactions are permitted. For these, the card is always the AGP master and the motherboard is always the AGP target. The card queues multiple requests which correspond to the PCI address phase, and the motherboard schedules the corresponding data phases later. An important part of initialization is telling the card the maximum number of outstanding AGP requests which may be queued at a given time.
AGP requests are similar to PCI memory read and write requests, but use a different encoding on command lines C/BE\[3:0\] and are always 8-byte aligned; their starting address and length are always multiples of 8 bytes (64 bits). The three low-order bits of the address are used instead to communicate the length of the request.
Whenever the PCI GNT# signal is asserted, granting the bus to the card, three additional status bits ST\[2:0\] indicate the type of transfer to be performed next. If the bits are `0xx`, a previously queued AGP transaction\'s data is to be transferred; if the three bits are `111`, the card may begin a PCI transaction or (if sideband addressing is not in use) queue a request in-band using PIPE#.
### AGP command codes {#agp_command_codes}
Like PCI, each AGP transaction begins with an address phase, communicating an address and 4-bit command code. The possible commands are different from PCI, however:
000p: Read
: Read 8×(AD\[2:0\]+1) = 8, 16, 24, \..., 64 bytes. The least significant bit p is 0 for low-priority, 1 for high.
001x: (reserved):\
010p: Write
: Write 8×(AD\[2:0\]+1) = 8--64 bytes.
011x: (reserved):\
100p: Long read
: Read 32×(AD\[2:0\]+1) = 32, 64, 96, \..., 256 bytes. This is the same as a read request, but the length is multiplied by four.
1010: Flush
: Force previously written data to memory, for synchronization. This acts as a low-priority read, taking a queue slot and returning 8 bytes of random data to indicate completion. The address and length supplied with this command are ignored.
1011: (reserved):\
1100: Fence
: This acts as a memory fence, requiring that all earlier AGP requests complete before any following requests. Ordinarily, for increased performance, AGP uses a very weak consistency model, and allows a later write to pass an earlier read. (E.g. after sending \"write 1, write 2, read, write 3, write 4\" requests, all to the same address, the read may return any value from 2 to 4. Only returning 1 is forbidden, as writes must complete before following reads.) This operation does not require any queue slots.
1101: Dual address cycle
: When making a request to an address above 2^32^, this is used to indicate that a second address cycle will follow with additional address bits. This operates like a regular PCI dual address cycle; it is accompanied by the low-order 32 bits of the address (and the length), and the following cycle includes the high 32 address bits and the desired command. The two cycles make one request, and take only one slot in the request queue. This request code is not used with side-band addressing.
111x: (reserved):
AGP 3.0 dropped high-priority requests and the long read commands, as they were little used. It also mandated side-band addressing, thus dropping the dual address cycle, leaving only four request types: low-priority read (0000), low-priority write (0100), flush (1010) and fence (1100).
### In-band AGP requests using PIPE# {#in_band_agp_requests_using_pipe}
To queue a request in-band, the card must request the bus using the standard PCI REQ# signal, and receive GNT# plus bus status ST\[2:0\] equal to `111`. Then, instead of asserting FRAME# to begin a PCI transaction, the card asserts the PIPE# signal while driving the AGP command, address, and length on the C/BE\[3:0\], AD\[31:3\] and AD\[2:0\] lines, respectively. (If the address is 64 bits, a dual address cycle similar to PCI is used.) For every cycle that PIPE# is asserted, the card sends another request without waiting for acknowledgement from the motherboard, up to the configured maximum queue depth. The last cycle is marked by deasserting REQ#, and PIPE# is deasserted on the following idle cycle.
### Side-band AGP requests using SBA\[7:0\] {#side_band_agp_requests_using_sba70}
If side-band addressing is supported and configured, the PIPE# signal is not used. (And the signal is re-used for another purpose in the AGP 3.0 protocol, which requires side-band addressing.) Instead, requests are broken into 16-bit pieces which are sent as two bytes across the SBA bus. There is no need for the card to ask permission from the motherboard; a new request may be sent at any time as long as the number of outstanding requests is within the configured maximum queue depth. The possible values are:
`0aaa aaaa aaaa alll`
: Queue a request with the given low-order address bits A\[14:3\] and length 8×(L\[2:0\]+1). The command and high-order bits are as previously specified. Any number of requests may be queued by sending only this pattern, as long as the command and higher address bits remain the same.
`10cc ccra aaaa aaaa`
: Use command C\[3:0\] and address bits A\[23:15\] for future requests. (Bit R is reserved.) This does not queue a request, but sets values that will be used in all future queued requests.
`110r aaaa aaaa aaaa`
: Use address bits A\[35:24\] for future requests.
`1110 aaaa aaaa aaaa`
: Use address bits A\[47:36\] for future requests.
`1111 0xxx`, `1111 10xx`, `1111 110x`
: *Reserved, do not use.*
`1111 1110`
: Synchronization pattern used when starting the SBA bus after an idle period.`{{r|agp10|agp20|p1=68|p2=163}}`{=mediawiki}
`1111 1111`
: No operation; no request. At AGP 1× speed, this may be sent as a single byte and a following 16-bit side-band request started one cycle later. At AGP 2× and higher speeds, all side-band requests, including this NOP, are 16 bits long.
Sideband address bytes are sent at the same rate as data transfers, up to 8× the 66 MHz basic bus clock. Sideband addressing has the advantage that it mostly eliminates the need for turnaround cycles on the AD bus between transfers, in the usual case when read operations greatly outnumber writes.
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# Accelerated Graphics Port
## Protocol
### AGP responses {#agp_responses}
While asserting GNT#, the motherboard may instead indicate via the ST bits that a data phase for a queued request will be performed next. There are four queues: two priorities (low- and high-priority) for each of reads and writes, and each is processed in order. Obviously, the motherboard will attempt to complete high-priority requests first, but there is no limit on the number of low-priority responses which may be delivered while the high-priority request is processed.
For each cycle when the GNT# is asserted and the status bits have the value `00p`, a read response of the indicated priority is scheduled to be returned. At the next available opportunity (typically the next clock cycle), the motherboard will assert TRDY# (target ready) and begin transferring the response to the oldest request in the indicated read queue. (Other PCI bus signals like FRAME#, DEVSEL# and IRDY# remain deasserted.) Up to four clock cycles worth of data (16 bytes at AGP 1× or 128 bytes at AGP 8×) are transferred without waiting for acknowledgement from the card. If the response is longer than that, both the card and motherboard must indicate their ability to continue on the third cycle by asserting IRDY# (initiator ready) and TRDY#, respectively. If either one does not, wait states will be inserted until two cycles after they both do. (The value of IRDY# and TRDY# at other times is irrelevant and they are usually deasserted.)
The C/BE# byte enable lines may be ignored during read responses, but are held asserted (all bytes valid) by the motherboard.
The card may also assert the RBF# (read buffer full) signal to indicate that it is temporarily unable to receive more low-priority read responses. The motherboard will refrain from scheduling any more low-priority read responses. The card must still be able to receive the end of the current response, and the first four-cycle block of the following one if scheduled, plus any high-priority responses it has requested.
For each cycle when GNT# is asserted and the status bits have the value `01p`, write data is scheduled to be sent across the bus. At the next available opportunity (typically the next clock cycle), the card will assert IRDY# (initiator ready) and begin transferring the data portion of the oldest request in the indicated write queue. If the data is longer than four clock cycles, the motherboard will indicate its ability to continue by asserting TRDY# on the third cycle. Unlike reads, there is no provision for the card to delay the write; if it didn\'t have the data ready to send, it shouldn\'t have queued the request.
The C/BE# lines *are* used with write data, and may be used by the card to select which bytes should be written to memory.
The multiplier in AGP 2×, 4× and 8× indicates the number of data transfers across the bus during each 66 MHz clock cycle. Such transfers use source synchronous clocking with a \"strobe\" signal (AD_STB\[0\], AD_STB\[1\], and SB_STB) generated by the data source. AGP 4× adds complementary strobe signals.
Because AGP transactions may be as short as two transfers, at AGP 4× and 8× speeds it is possible for a request to complete in the middle of a clock cycle. In such a case, the cycle is padded with dummy data transfers (with the C/BE# byte enable lines held deasserted).
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